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Diffstat (limited to 'contrib/llvm-project/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp')
| -rw-r--r-- | contrib/llvm-project/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp | 10643 |
1 files changed, 10643 insertions, 0 deletions
diff --git a/contrib/llvm-project/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/contrib/llvm-project/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp new file mode 100644 index 000000000000..421ff3e7d472 --- /dev/null +++ b/contrib/llvm-project/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp @@ -0,0 +1,10643 @@ +//===- SelectionDAGBuilder.cpp - Selection-DAG building -------------------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// +// +// This implements routines for translating from LLVM IR into SelectionDAG IR. +// +//===----------------------------------------------------------------------===// + +#include "SelectionDAGBuilder.h" +#include "SDNodeDbgValue.h" +#include "llvm/ADT/APFloat.h" +#include "llvm/ADT/APInt.h" +#include "llvm/ADT/ArrayRef.h" +#include "llvm/ADT/BitVector.h" +#include "llvm/ADT/DenseMap.h" +#include "llvm/ADT/None.h" +#include "llvm/ADT/Optional.h" +#include "llvm/ADT/STLExtras.h" +#include "llvm/ADT/SmallPtrSet.h" +#include "llvm/ADT/SmallSet.h" +#include "llvm/ADT/SmallVector.h" +#include "llvm/ADT/StringRef.h" +#include "llvm/ADT/Triple.h" +#include "llvm/ADT/Twine.h" +#include "llvm/Analysis/AliasAnalysis.h" +#include "llvm/Analysis/BlockFrequencyInfo.h" +#include "llvm/Analysis/BranchProbabilityInfo.h" +#include "llvm/Analysis/ConstantFolding.h" +#include "llvm/Analysis/EHPersonalities.h" +#include "llvm/Analysis/Loads.h" +#include "llvm/Analysis/MemoryLocation.h" +#include "llvm/Analysis/ProfileSummaryInfo.h" +#include "llvm/Analysis/TargetLibraryInfo.h" +#include "llvm/Analysis/ValueTracking.h" +#include "llvm/Analysis/VectorUtils.h" +#include "llvm/CodeGen/Analysis.h" +#include "llvm/CodeGen/FunctionLoweringInfo.h" +#include "llvm/CodeGen/GCMetadata.h" +#include "llvm/CodeGen/ISDOpcodes.h" +#include "llvm/CodeGen/MachineBasicBlock.h" +#include "llvm/CodeGen/MachineFrameInfo.h" +#include "llvm/CodeGen/MachineFunction.h" +#include "llvm/CodeGen/MachineInstr.h" +#include "llvm/CodeGen/MachineInstrBuilder.h" +#include "llvm/CodeGen/MachineJumpTableInfo.h" +#include "llvm/CodeGen/MachineMemOperand.h" +#include "llvm/CodeGen/MachineModuleInfo.h" +#include "llvm/CodeGen/MachineOperand.h" +#include "llvm/CodeGen/MachineRegisterInfo.h" +#include "llvm/CodeGen/RuntimeLibcalls.h" +#include "llvm/CodeGen/SelectionDAG.h" +#include "llvm/CodeGen/SelectionDAGNodes.h" +#include "llvm/CodeGen/SelectionDAGTargetInfo.h" +#include "llvm/CodeGen/StackMaps.h" +#include "llvm/CodeGen/SwiftErrorValueTracking.h" +#include "llvm/CodeGen/TargetFrameLowering.h" +#include "llvm/CodeGen/TargetInstrInfo.h" +#include "llvm/CodeGen/TargetLowering.h" +#include "llvm/CodeGen/TargetOpcodes.h" +#include "llvm/CodeGen/TargetRegisterInfo.h" +#include "llvm/CodeGen/TargetSubtargetInfo.h" +#include "llvm/CodeGen/ValueTypes.h" +#include "llvm/CodeGen/WinEHFuncInfo.h" +#include "llvm/IR/Argument.h" +#include "llvm/IR/Attributes.h" +#include "llvm/IR/BasicBlock.h" +#include "llvm/IR/CFG.h" +#include "llvm/IR/CallSite.h" +#include "llvm/IR/CallingConv.h" +#include "llvm/IR/Constant.h" +#include "llvm/IR/ConstantRange.h" +#include "llvm/IR/Constants.h" +#include "llvm/IR/DataLayout.h" +#include "llvm/IR/DebugInfoMetadata.h" +#include "llvm/IR/DebugLoc.h" +#include "llvm/IR/DerivedTypes.h" +#include "llvm/IR/Function.h" +#include "llvm/IR/GetElementPtrTypeIterator.h" +#include "llvm/IR/InlineAsm.h" +#include "llvm/IR/InstrTypes.h" +#include "llvm/IR/Instruction.h" +#include "llvm/IR/Instructions.h" +#include "llvm/IR/IntrinsicInst.h" +#include "llvm/IR/Intrinsics.h" +#include "llvm/IR/IntrinsicsAArch64.h" +#include "llvm/IR/IntrinsicsWebAssembly.h" +#include "llvm/IR/LLVMContext.h" +#include "llvm/IR/Metadata.h" +#include "llvm/IR/Module.h" +#include "llvm/IR/Operator.h" +#include "llvm/IR/PatternMatch.h" +#include "llvm/IR/Statepoint.h" +#include "llvm/IR/Type.h" +#include "llvm/IR/User.h" +#include "llvm/IR/Value.h" +#include "llvm/MC/MCContext.h" +#include "llvm/MC/MCSymbol.h" +#include "llvm/Support/AtomicOrdering.h" +#include "llvm/Support/BranchProbability.h" +#include "llvm/Support/Casting.h" +#include "llvm/Support/CodeGen.h" +#include "llvm/Support/CommandLine.h" +#include "llvm/Support/Compiler.h" +#include "llvm/Support/Debug.h" +#include "llvm/Support/ErrorHandling.h" +#include "llvm/Support/MachineValueType.h" +#include "llvm/Support/MathExtras.h" +#include "llvm/Support/raw_ostream.h" +#include "llvm/Target/TargetIntrinsicInfo.h" +#include "llvm/Target/TargetMachine.h" +#include "llvm/Target/TargetOptions.h" +#include "llvm/Transforms/Utils/Local.h" +#include <algorithm> +#include <cassert> +#include <cstddef> +#include <cstdint> +#include <cstring> +#include <iterator> +#include <limits> +#include <numeric> +#include <tuple> +#include <utility> +#include <vector> + +using namespace llvm; +using namespace PatternMatch; +using namespace SwitchCG; + +#define DEBUG_TYPE "isel" + +/// LimitFloatPrecision - Generate low-precision inline sequences for +/// some float libcalls (6, 8 or 12 bits). +static unsigned LimitFloatPrecision; + +static cl::opt<unsigned, true> + LimitFPPrecision("limit-float-precision", + cl::desc("Generate low-precision inline sequences " + "for some float libcalls"), + cl::location(LimitFloatPrecision), cl::Hidden, + cl::init(0)); + +static cl::opt<unsigned> SwitchPeelThreshold( + "switch-peel-threshold", cl::Hidden, cl::init(66), + cl::desc("Set the case probability threshold for peeling the case from a " + "switch statement. A value greater than 100 will void this " + "optimization")); + +// Limit the width of DAG chains. This is important in general to prevent +// DAG-based analysis from blowing up. For example, alias analysis and +// load clustering may not complete in reasonable time. It is difficult to +// recognize and avoid this situation within each individual analysis, and +// future analyses are likely to have the same behavior. Limiting DAG width is +// the safe approach and will be especially important with global DAGs. +// +// MaxParallelChains default is arbitrarily high to avoid affecting +// optimization, but could be lowered to improve compile time. Any ld-ld-st-st +// sequence over this should have been converted to llvm.memcpy by the +// frontend. It is easy to induce this behavior with .ll code such as: +// %buffer = alloca [4096 x i8] +// %data = load [4096 x i8]* %argPtr +// store [4096 x i8] %data, [4096 x i8]* %buffer +static const unsigned MaxParallelChains = 64; + +// Return the calling convention if the Value passed requires ABI mangling as it +// is a parameter to a function or a return value from a function which is not +// an intrinsic. +static Optional<CallingConv::ID> getABIRegCopyCC(const Value *V) { + if (auto *R = dyn_cast<ReturnInst>(V)) + return R->getParent()->getParent()->getCallingConv(); + + if (auto *CI = dyn_cast<CallInst>(V)) { + const bool IsInlineAsm = CI->isInlineAsm(); + const bool IsIndirectFunctionCall = + !IsInlineAsm && !CI->getCalledFunction(); + + // It is possible that the call instruction is an inline asm statement or an + // indirect function call in which case the return value of + // getCalledFunction() would be nullptr. + const bool IsInstrinsicCall = + !IsInlineAsm && !IsIndirectFunctionCall && + CI->getCalledFunction()->getIntrinsicID() != Intrinsic::not_intrinsic; + + if (!IsInlineAsm && !IsInstrinsicCall) + return CI->getCallingConv(); + } + + return None; +} + +static SDValue getCopyFromPartsVector(SelectionDAG &DAG, const SDLoc &DL, + const SDValue *Parts, unsigned NumParts, + MVT PartVT, EVT ValueVT, const Value *V, + Optional<CallingConv::ID> CC); + +/// getCopyFromParts - Create a value that contains the specified legal parts +/// combined into the value they represent. If the parts combine to a type +/// larger than ValueVT then AssertOp can be used to specify whether the extra +/// bits are known to be zero (ISD::AssertZext) or sign extended from ValueVT +/// (ISD::AssertSext). +static SDValue getCopyFromParts(SelectionDAG &DAG, const SDLoc &DL, + const SDValue *Parts, unsigned NumParts, + MVT PartVT, EVT ValueVT, const Value *V, + Optional<CallingConv::ID> CC = None, + Optional<ISD::NodeType> AssertOp = None) { + if (ValueVT.isVector()) + return getCopyFromPartsVector(DAG, DL, Parts, NumParts, PartVT, ValueVT, V, + CC); + + assert(NumParts > 0 && "No parts to assemble!"); + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + SDValue Val = Parts[0]; + + if (NumParts > 1) { + // Assemble the value from multiple parts. + if (ValueVT.isInteger()) { + unsigned PartBits = PartVT.getSizeInBits(); + unsigned ValueBits = ValueVT.getSizeInBits(); + + // Assemble the power of 2 part. + unsigned RoundParts = + (NumParts & (NumParts - 1)) ? 1 << Log2_32(NumParts) : NumParts; + unsigned RoundBits = PartBits * RoundParts; + EVT RoundVT = RoundBits == ValueBits ? + ValueVT : EVT::getIntegerVT(*DAG.getContext(), RoundBits); + SDValue Lo, Hi; + + EVT HalfVT = EVT::getIntegerVT(*DAG.getContext(), RoundBits/2); + + if (RoundParts > 2) { + Lo = getCopyFromParts(DAG, DL, Parts, RoundParts / 2, + PartVT, HalfVT, V); + Hi = getCopyFromParts(DAG, DL, Parts + RoundParts / 2, + RoundParts / 2, PartVT, HalfVT, V); + } else { + Lo = DAG.getNode(ISD::BITCAST, DL, HalfVT, Parts[0]); + Hi = DAG.getNode(ISD::BITCAST, DL, HalfVT, Parts[1]); + } + + if (DAG.getDataLayout().isBigEndian()) + std::swap(Lo, Hi); + + Val = DAG.getNode(ISD::BUILD_PAIR, DL, RoundVT, Lo, Hi); + + if (RoundParts < NumParts) { + // Assemble the trailing non-power-of-2 part. + unsigned OddParts = NumParts - RoundParts; + EVT OddVT = EVT::getIntegerVT(*DAG.getContext(), OddParts * PartBits); + Hi = getCopyFromParts(DAG, DL, Parts + RoundParts, OddParts, PartVT, + OddVT, V, CC); + + // Combine the round and odd parts. + Lo = Val; + if (DAG.getDataLayout().isBigEndian()) + std::swap(Lo, Hi); + EVT TotalVT = EVT::getIntegerVT(*DAG.getContext(), NumParts * PartBits); + Hi = DAG.getNode(ISD::ANY_EXTEND, DL, TotalVT, Hi); + Hi = + DAG.getNode(ISD::SHL, DL, TotalVT, Hi, + DAG.getConstant(Lo.getValueSizeInBits(), DL, + TLI.getPointerTy(DAG.getDataLayout()))); + Lo = DAG.getNode(ISD::ZERO_EXTEND, DL, TotalVT, Lo); + Val = DAG.getNode(ISD::OR, DL, TotalVT, Lo, Hi); + } + } else if (PartVT.isFloatingPoint()) { + // FP split into multiple FP parts (for ppcf128) + assert(ValueVT == EVT(MVT::ppcf128) && PartVT == MVT::f64 && + "Unexpected split"); + SDValue Lo, Hi; + Lo = DAG.getNode(ISD::BITCAST, DL, EVT(MVT::f64), Parts[0]); + Hi = DAG.getNode(ISD::BITCAST, DL, EVT(MVT::f64), Parts[1]); + if (TLI.hasBigEndianPartOrdering(ValueVT, DAG.getDataLayout())) + std::swap(Lo, Hi); + Val = DAG.getNode(ISD::BUILD_PAIR, DL, ValueVT, Lo, Hi); + } else { + // FP split into integer parts (soft fp) + assert(ValueVT.isFloatingPoint() && PartVT.isInteger() && + !PartVT.isVector() && "Unexpected split"); + EVT IntVT = EVT::getIntegerVT(*DAG.getContext(), ValueVT.getSizeInBits()); + Val = getCopyFromParts(DAG, DL, Parts, NumParts, PartVT, IntVT, V, CC); + } + } + + // There is now one part, held in Val. Correct it to match ValueVT. + // PartEVT is the type of the register class that holds the value. + // ValueVT is the type of the inline asm operation. + EVT PartEVT = Val.getValueType(); + + if (PartEVT == ValueVT) + return Val; + + if (PartEVT.isInteger() && ValueVT.isFloatingPoint() && + ValueVT.bitsLT(PartEVT)) { + // For an FP value in an integer part, we need to truncate to the right + // width first. + PartEVT = EVT::getIntegerVT(*DAG.getContext(), ValueVT.getSizeInBits()); + Val = DAG.getNode(ISD::TRUNCATE, DL, PartEVT, Val); + } + + // Handle types that have the same size. + if (PartEVT.getSizeInBits() == ValueVT.getSizeInBits()) + return DAG.getNode(ISD::BITCAST, DL, ValueVT, Val); + + // Handle types with different sizes. + if (PartEVT.isInteger() && ValueVT.isInteger()) { + if (ValueVT.bitsLT(PartEVT)) { + // For a truncate, see if we have any information to + // indicate whether the truncated bits will always be + // zero or sign-extension. + if (AssertOp.hasValue()) + Val = DAG.getNode(*AssertOp, DL, PartEVT, Val, + DAG.getValueType(ValueVT)); + return DAG.getNode(ISD::TRUNCATE, DL, ValueVT, Val); + } + return DAG.getNode(ISD::ANY_EXTEND, DL, ValueVT, Val); + } + + if (PartEVT.isFloatingPoint() && ValueVT.isFloatingPoint()) { + // FP_ROUND's are always exact here. + if (ValueVT.bitsLT(Val.getValueType())) + return DAG.getNode( + ISD::FP_ROUND, DL, ValueVT, Val, + DAG.getTargetConstant(1, DL, TLI.getPointerTy(DAG.getDataLayout()))); + + return DAG.getNode(ISD::FP_EXTEND, DL, ValueVT, Val); + } + + // Handle MMX to a narrower integer type by bitcasting MMX to integer and + // then truncating. + if (PartEVT == MVT::x86mmx && ValueVT.isInteger() && + ValueVT.bitsLT(PartEVT)) { + Val = DAG.getNode(ISD::BITCAST, DL, MVT::i64, Val); + return DAG.getNode(ISD::TRUNCATE, DL, ValueVT, Val); + } + + report_fatal_error("Unknown mismatch in getCopyFromParts!"); +} + +static void diagnosePossiblyInvalidConstraint(LLVMContext &Ctx, const Value *V, + const Twine &ErrMsg) { + const Instruction *I = dyn_cast_or_null<Instruction>(V); + if (!V) + return Ctx.emitError(ErrMsg); + + const char *AsmError = ", possible invalid constraint for vector type"; + if (const CallInst *CI = dyn_cast<CallInst>(I)) + if (isa<InlineAsm>(CI->getCalledValue())) + return Ctx.emitError(I, ErrMsg + AsmError); + + return Ctx.emitError(I, ErrMsg); +} + +/// getCopyFromPartsVector - Create a value that contains the specified legal +/// parts combined into the value they represent. If the parts combine to a +/// type larger than ValueVT then AssertOp can be used to specify whether the +/// extra bits are known to be zero (ISD::AssertZext) or sign extended from +/// ValueVT (ISD::AssertSext). +static SDValue getCopyFromPartsVector(SelectionDAG &DAG, const SDLoc &DL, + const SDValue *Parts, unsigned NumParts, + MVT PartVT, EVT ValueVT, const Value *V, + Optional<CallingConv::ID> CallConv) { + assert(ValueVT.isVector() && "Not a vector value"); + assert(NumParts > 0 && "No parts to assemble!"); + const bool IsABIRegCopy = CallConv.hasValue(); + + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + SDValue Val = Parts[0]; + + // Handle a multi-element vector. + if (NumParts > 1) { + EVT IntermediateVT; + MVT RegisterVT; + unsigned NumIntermediates; + unsigned NumRegs; + + if (IsABIRegCopy) { + NumRegs = TLI.getVectorTypeBreakdownForCallingConv( + *DAG.getContext(), CallConv.getValue(), ValueVT, IntermediateVT, + NumIntermediates, RegisterVT); + } else { + NumRegs = + TLI.getVectorTypeBreakdown(*DAG.getContext(), ValueVT, IntermediateVT, + NumIntermediates, RegisterVT); + } + + assert(NumRegs == NumParts && "Part count doesn't match vector breakdown!"); + NumParts = NumRegs; // Silence a compiler warning. + assert(RegisterVT == PartVT && "Part type doesn't match vector breakdown!"); + assert(RegisterVT.getSizeInBits() == + Parts[0].getSimpleValueType().getSizeInBits() && + "Part type sizes don't match!"); + + // Assemble the parts into intermediate operands. + SmallVector<SDValue, 8> Ops(NumIntermediates); + if (NumIntermediates == NumParts) { + // If the register was not expanded, truncate or copy the value, + // as appropriate. + for (unsigned i = 0; i != NumParts; ++i) + Ops[i] = getCopyFromParts(DAG, DL, &Parts[i], 1, + PartVT, IntermediateVT, V); + } else if (NumParts > 0) { + // If the intermediate type was expanded, build the intermediate + // operands from the parts. + assert(NumParts % NumIntermediates == 0 && + "Must expand into a divisible number of parts!"); + unsigned Factor = NumParts / NumIntermediates; + for (unsigned i = 0; i != NumIntermediates; ++i) + Ops[i] = getCopyFromParts(DAG, DL, &Parts[i * Factor], Factor, + PartVT, IntermediateVT, V); + } + + // Build a vector with BUILD_VECTOR or CONCAT_VECTORS from the + // intermediate operands. + EVT BuiltVectorTy = + EVT::getVectorVT(*DAG.getContext(), IntermediateVT.getScalarType(), + (IntermediateVT.isVector() + ? IntermediateVT.getVectorNumElements() * NumParts + : NumIntermediates)); + Val = DAG.getNode(IntermediateVT.isVector() ? ISD::CONCAT_VECTORS + : ISD::BUILD_VECTOR, + DL, BuiltVectorTy, Ops); + } + + // There is now one part, held in Val. Correct it to match ValueVT. + EVT PartEVT = Val.getValueType(); + + if (PartEVT == ValueVT) + return Val; + + if (PartEVT.isVector()) { + // If the element type of the source/dest vectors are the same, but the + // parts vector has more elements than the value vector, then we have a + // vector widening case (e.g. <2 x float> -> <4 x float>). Extract the + // elements we want. + if (PartEVT.getVectorElementType() == ValueVT.getVectorElementType()) { + assert(PartEVT.getVectorNumElements() > ValueVT.getVectorNumElements() && + "Cannot narrow, it would be a lossy transformation"); + return DAG.getNode( + ISD::EXTRACT_SUBVECTOR, DL, ValueVT, Val, + DAG.getConstant(0, DL, TLI.getVectorIdxTy(DAG.getDataLayout()))); + } + + // Vector/Vector bitcast. + if (ValueVT.getSizeInBits() == PartEVT.getSizeInBits()) + return DAG.getNode(ISD::BITCAST, DL, ValueVT, Val); + + assert(PartEVT.getVectorNumElements() == ValueVT.getVectorNumElements() && + "Cannot handle this kind of promotion"); + // Promoted vector extract + return DAG.getAnyExtOrTrunc(Val, DL, ValueVT); + + } + + // Trivial bitcast if the types are the same size and the destination + // vector type is legal. + if (PartEVT.getSizeInBits() == ValueVT.getSizeInBits() && + TLI.isTypeLegal(ValueVT)) + return DAG.getNode(ISD::BITCAST, DL, ValueVT, Val); + + if (ValueVT.getVectorNumElements() != 1) { + // Certain ABIs require that vectors are passed as integers. For vectors + // are the same size, this is an obvious bitcast. + if (ValueVT.getSizeInBits() == PartEVT.getSizeInBits()) { + return DAG.getNode(ISD::BITCAST, DL, ValueVT, Val); + } else if (ValueVT.getSizeInBits() < PartEVT.getSizeInBits()) { + // Bitcast Val back the original type and extract the corresponding + // vector we want. + unsigned Elts = PartEVT.getSizeInBits() / ValueVT.getScalarSizeInBits(); + EVT WiderVecType = EVT::getVectorVT(*DAG.getContext(), + ValueVT.getVectorElementType(), Elts); + Val = DAG.getBitcast(WiderVecType, Val); + return DAG.getNode( + ISD::EXTRACT_SUBVECTOR, DL, ValueVT, Val, + DAG.getConstant(0, DL, TLI.getVectorIdxTy(DAG.getDataLayout()))); + } + + diagnosePossiblyInvalidConstraint( + *DAG.getContext(), V, "non-trivial scalar-to-vector conversion"); + return DAG.getUNDEF(ValueVT); + } + + // Handle cases such as i8 -> <1 x i1> + EVT ValueSVT = ValueVT.getVectorElementType(); + if (ValueVT.getVectorNumElements() == 1 && ValueSVT != PartEVT) + Val = ValueVT.isFloatingPoint() ? DAG.getFPExtendOrRound(Val, DL, ValueSVT) + : DAG.getAnyExtOrTrunc(Val, DL, ValueSVT); + + return DAG.getBuildVector(ValueVT, DL, Val); +} + +static void getCopyToPartsVector(SelectionDAG &DAG, const SDLoc &dl, + SDValue Val, SDValue *Parts, unsigned NumParts, + MVT PartVT, const Value *V, + Optional<CallingConv::ID> CallConv); + +/// getCopyToParts - Create a series of nodes that contain the specified value +/// split into legal parts. If the parts contain more bits than Val, then, for +/// integers, ExtendKind can be used to specify how to generate the extra bits. +static void getCopyToParts(SelectionDAG &DAG, const SDLoc &DL, SDValue Val, + SDValue *Parts, unsigned NumParts, MVT PartVT, + const Value *V, + Optional<CallingConv::ID> CallConv = None, + ISD::NodeType ExtendKind = ISD::ANY_EXTEND) { + EVT ValueVT = Val.getValueType(); + + // Handle the vector case separately. + if (ValueVT.isVector()) + return getCopyToPartsVector(DAG, DL, Val, Parts, NumParts, PartVT, V, + CallConv); + + unsigned PartBits = PartVT.getSizeInBits(); + unsigned OrigNumParts = NumParts; + assert(DAG.getTargetLoweringInfo().isTypeLegal(PartVT) && + "Copying to an illegal type!"); + + if (NumParts == 0) + return; + + assert(!ValueVT.isVector() && "Vector case handled elsewhere"); + EVT PartEVT = PartVT; + if (PartEVT == ValueVT) { + assert(NumParts == 1 && "No-op copy with multiple parts!"); + Parts[0] = Val; + return; + } + + if (NumParts * PartBits > ValueVT.getSizeInBits()) { + // If the parts cover more bits than the value has, promote the value. + if (PartVT.isFloatingPoint() && ValueVT.isFloatingPoint()) { + assert(NumParts == 1 && "Do not know what to promote to!"); + Val = DAG.getNode(ISD::FP_EXTEND, DL, PartVT, Val); + } else { + if (ValueVT.isFloatingPoint()) { + // FP values need to be bitcast, then extended if they are being put + // into a larger container. + ValueVT = EVT::getIntegerVT(*DAG.getContext(), ValueVT.getSizeInBits()); + Val = DAG.getNode(ISD::BITCAST, DL, ValueVT, Val); + } + assert((PartVT.isInteger() || PartVT == MVT::x86mmx) && + ValueVT.isInteger() && + "Unknown mismatch!"); + ValueVT = EVT::getIntegerVT(*DAG.getContext(), NumParts * PartBits); + Val = DAG.getNode(ExtendKind, DL, ValueVT, Val); + if (PartVT == MVT::x86mmx) + Val = DAG.getNode(ISD::BITCAST, DL, PartVT, Val); + } + } else if (PartBits == ValueVT.getSizeInBits()) { + // Different types of the same size. + assert(NumParts == 1 && PartEVT != ValueVT); + Val = DAG.getNode(ISD::BITCAST, DL, PartVT, Val); + } else if (NumParts * PartBits < ValueVT.getSizeInBits()) { + // If the parts cover less bits than value has, truncate the value. + assert((PartVT.isInteger() || PartVT == MVT::x86mmx) && + ValueVT.isInteger() && + "Unknown mismatch!"); + ValueVT = EVT::getIntegerVT(*DAG.getContext(), NumParts * PartBits); + Val = DAG.getNode(ISD::TRUNCATE, DL, ValueVT, Val); + if (PartVT == MVT::x86mmx) + Val = DAG.getNode(ISD::BITCAST, DL, PartVT, Val); + } + + // The value may have changed - recompute ValueVT. + ValueVT = Val.getValueType(); + assert(NumParts * PartBits == ValueVT.getSizeInBits() && + "Failed to tile the value with PartVT!"); + + if (NumParts == 1) { + if (PartEVT != ValueVT) { + diagnosePossiblyInvalidConstraint(*DAG.getContext(), V, + "scalar-to-vector conversion failed"); + Val = DAG.getNode(ISD::BITCAST, DL, PartVT, Val); + } + + Parts[0] = Val; + return; + } + + // Expand the value into multiple parts. + if (NumParts & (NumParts - 1)) { + // The number of parts is not a power of 2. Split off and copy the tail. + assert(PartVT.isInteger() && ValueVT.isInteger() && + "Do not know what to expand to!"); + unsigned RoundParts = 1 << Log2_32(NumParts); + unsigned RoundBits = RoundParts * PartBits; + unsigned OddParts = NumParts - RoundParts; + SDValue OddVal = DAG.getNode(ISD::SRL, DL, ValueVT, Val, + DAG.getShiftAmountConstant(RoundBits, ValueVT, DL, /*LegalTypes*/false)); + + getCopyToParts(DAG, DL, OddVal, Parts + RoundParts, OddParts, PartVT, V, + CallConv); + + if (DAG.getDataLayout().isBigEndian()) + // The odd parts were reversed by getCopyToParts - unreverse them. + std::reverse(Parts + RoundParts, Parts + NumParts); + + NumParts = RoundParts; + ValueVT = EVT::getIntegerVT(*DAG.getContext(), NumParts * PartBits); + Val = DAG.getNode(ISD::TRUNCATE, DL, ValueVT, Val); + } + + // The number of parts is a power of 2. Repeatedly bisect the value using + // EXTRACT_ELEMENT. + Parts[0] = DAG.getNode(ISD::BITCAST, DL, + EVT::getIntegerVT(*DAG.getContext(), + ValueVT.getSizeInBits()), + Val); + + for (unsigned StepSize = NumParts; StepSize > 1; StepSize /= 2) { + for (unsigned i = 0; i < NumParts; i += StepSize) { + unsigned ThisBits = StepSize * PartBits / 2; + EVT ThisVT = EVT::getIntegerVT(*DAG.getContext(), ThisBits); + SDValue &Part0 = Parts[i]; + SDValue &Part1 = Parts[i+StepSize/2]; + + Part1 = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, + ThisVT, Part0, DAG.getIntPtrConstant(1, DL)); + Part0 = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, + ThisVT, Part0, DAG.getIntPtrConstant(0, DL)); + + if (ThisBits == PartBits && ThisVT != PartVT) { + Part0 = DAG.getNode(ISD::BITCAST, DL, PartVT, Part0); + Part1 = DAG.getNode(ISD::BITCAST, DL, PartVT, Part1); + } + } + } + + if (DAG.getDataLayout().isBigEndian()) + std::reverse(Parts, Parts + OrigNumParts); +} + +static SDValue widenVectorToPartType(SelectionDAG &DAG, + SDValue Val, const SDLoc &DL, EVT PartVT) { + if (!PartVT.isVector()) + return SDValue(); + + EVT ValueVT = Val.getValueType(); + unsigned PartNumElts = PartVT.getVectorNumElements(); + unsigned ValueNumElts = ValueVT.getVectorNumElements(); + if (PartNumElts > ValueNumElts && + PartVT.getVectorElementType() == ValueVT.getVectorElementType()) { + EVT ElementVT = PartVT.getVectorElementType(); + // Vector widening case, e.g. <2 x float> -> <4 x float>. Shuffle in + // undef elements. + SmallVector<SDValue, 16> Ops; + DAG.ExtractVectorElements(Val, Ops); + SDValue EltUndef = DAG.getUNDEF(ElementVT); + for (unsigned i = ValueNumElts, e = PartNumElts; i != e; ++i) + Ops.push_back(EltUndef); + + // FIXME: Use CONCAT for 2x -> 4x. + return DAG.getBuildVector(PartVT, DL, Ops); + } + + return SDValue(); +} + +/// getCopyToPartsVector - Create a series of nodes that contain the specified +/// value split into legal parts. +static void getCopyToPartsVector(SelectionDAG &DAG, const SDLoc &DL, + SDValue Val, SDValue *Parts, unsigned NumParts, + MVT PartVT, const Value *V, + Optional<CallingConv::ID> CallConv) { + EVT ValueVT = Val.getValueType(); + assert(ValueVT.isVector() && "Not a vector"); + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + const bool IsABIRegCopy = CallConv.hasValue(); + + if (NumParts == 1) { + EVT PartEVT = PartVT; + if (PartEVT == ValueVT) { + // Nothing to do. + } else if (PartVT.getSizeInBits() == ValueVT.getSizeInBits()) { + // Bitconvert vector->vector case. + Val = DAG.getNode(ISD::BITCAST, DL, PartVT, Val); + } else if (SDValue Widened = widenVectorToPartType(DAG, Val, DL, PartVT)) { + Val = Widened; + } else if (PartVT.isVector() && + PartEVT.getVectorElementType().bitsGE( + ValueVT.getVectorElementType()) && + PartEVT.getVectorNumElements() == ValueVT.getVectorNumElements()) { + + // Promoted vector extract + Val = DAG.getAnyExtOrTrunc(Val, DL, PartVT); + } else { + if (ValueVT.getVectorNumElements() == 1) { + Val = DAG.getNode( + ISD::EXTRACT_VECTOR_ELT, DL, PartVT, Val, + DAG.getConstant(0, DL, TLI.getVectorIdxTy(DAG.getDataLayout()))); + } else { + assert(PartVT.getSizeInBits() > ValueVT.getSizeInBits() && + "lossy conversion of vector to scalar type"); + EVT IntermediateType = + EVT::getIntegerVT(*DAG.getContext(), ValueVT.getSizeInBits()); + Val = DAG.getBitcast(IntermediateType, Val); + Val = DAG.getAnyExtOrTrunc(Val, DL, PartVT); + } + } + + assert(Val.getValueType() == PartVT && "Unexpected vector part value type"); + Parts[0] = Val; + return; + } + + // Handle a multi-element vector. + EVT IntermediateVT; + MVT RegisterVT; + unsigned NumIntermediates; + unsigned NumRegs; + if (IsABIRegCopy) { + NumRegs = TLI.getVectorTypeBreakdownForCallingConv( + *DAG.getContext(), CallConv.getValue(), ValueVT, IntermediateVT, + NumIntermediates, RegisterVT); + } else { + NumRegs = + TLI.getVectorTypeBreakdown(*DAG.getContext(), ValueVT, IntermediateVT, + NumIntermediates, RegisterVT); + } + + assert(NumRegs == NumParts && "Part count doesn't match vector breakdown!"); + NumParts = NumRegs; // Silence a compiler warning. + assert(RegisterVT == PartVT && "Part type doesn't match vector breakdown!"); + + unsigned IntermediateNumElts = IntermediateVT.isVector() ? + IntermediateVT.getVectorNumElements() : 1; + + // Convert the vector to the appropriate type if necessary. + unsigned DestVectorNoElts = NumIntermediates * IntermediateNumElts; + + EVT BuiltVectorTy = EVT::getVectorVT( + *DAG.getContext(), IntermediateVT.getScalarType(), DestVectorNoElts); + MVT IdxVT = TLI.getVectorIdxTy(DAG.getDataLayout()); + if (ValueVT != BuiltVectorTy) { + if (SDValue Widened = widenVectorToPartType(DAG, Val, DL, BuiltVectorTy)) + Val = Widened; + + Val = DAG.getNode(ISD::BITCAST, DL, BuiltVectorTy, Val); + } + + // Split the vector into intermediate operands. + SmallVector<SDValue, 8> Ops(NumIntermediates); + for (unsigned i = 0; i != NumIntermediates; ++i) { + if (IntermediateVT.isVector()) { + Ops[i] = DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, IntermediateVT, Val, + DAG.getConstant(i * IntermediateNumElts, DL, IdxVT)); + } else { + Ops[i] = DAG.getNode( + ISD::EXTRACT_VECTOR_ELT, DL, IntermediateVT, Val, + DAG.getConstant(i, DL, IdxVT)); + } + } + + // Split the intermediate operands into legal parts. + if (NumParts == NumIntermediates) { + // If the register was not expanded, promote or copy the value, + // as appropriate. + for (unsigned i = 0; i != NumParts; ++i) + getCopyToParts(DAG, DL, Ops[i], &Parts[i], 1, PartVT, V, CallConv); + } else if (NumParts > 0) { + // If the intermediate type was expanded, split each the value into + // legal parts. + assert(NumIntermediates != 0 && "division by zero"); + assert(NumParts % NumIntermediates == 0 && + "Must expand into a divisible number of parts!"); + unsigned Factor = NumParts / NumIntermediates; + for (unsigned i = 0; i != NumIntermediates; ++i) + getCopyToParts(DAG, DL, Ops[i], &Parts[i * Factor], Factor, PartVT, V, + CallConv); + } +} + +RegsForValue::RegsForValue(const SmallVector<unsigned, 4> ®s, MVT regvt, + EVT valuevt, Optional<CallingConv::ID> CC) + : ValueVTs(1, valuevt), RegVTs(1, regvt), Regs(regs), + RegCount(1, regs.size()), CallConv(CC) {} + +RegsForValue::RegsForValue(LLVMContext &Context, const TargetLowering &TLI, + const DataLayout &DL, unsigned Reg, Type *Ty, + Optional<CallingConv::ID> CC) { + ComputeValueVTs(TLI, DL, Ty, ValueVTs); + + CallConv = CC; + + for (EVT ValueVT : ValueVTs) { + unsigned NumRegs = + isABIMangled() + ? TLI.getNumRegistersForCallingConv(Context, CC.getValue(), ValueVT) + : TLI.getNumRegisters(Context, ValueVT); + MVT RegisterVT = + isABIMangled() + ? TLI.getRegisterTypeForCallingConv(Context, CC.getValue(), ValueVT) + : TLI.getRegisterType(Context, ValueVT); + for (unsigned i = 0; i != NumRegs; ++i) + Regs.push_back(Reg + i); + RegVTs.push_back(RegisterVT); + RegCount.push_back(NumRegs); + Reg += NumRegs; + } +} + +SDValue RegsForValue::getCopyFromRegs(SelectionDAG &DAG, + FunctionLoweringInfo &FuncInfo, + const SDLoc &dl, SDValue &Chain, + SDValue *Flag, const Value *V) const { + // A Value with type {} or [0 x %t] needs no registers. + if (ValueVTs.empty()) + return SDValue(); + + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + + // Assemble the legal parts into the final values. + SmallVector<SDValue, 4> Values(ValueVTs.size()); + SmallVector<SDValue, 8> Parts; + for (unsigned Value = 0, Part = 0, e = ValueVTs.size(); Value != e; ++Value) { + // Copy the legal parts from the registers. + EVT ValueVT = ValueVTs[Value]; + unsigned NumRegs = RegCount[Value]; + MVT RegisterVT = isABIMangled() ? TLI.getRegisterTypeForCallingConv( + *DAG.getContext(), + CallConv.getValue(), RegVTs[Value]) + : RegVTs[Value]; + + Parts.resize(NumRegs); + for (unsigned i = 0; i != NumRegs; ++i) { + SDValue P; + if (!Flag) { + P = DAG.getCopyFromReg(Chain, dl, Regs[Part+i], RegisterVT); + } else { + P = DAG.getCopyFromReg(Chain, dl, Regs[Part+i], RegisterVT, *Flag); + *Flag = P.getValue(2); + } + + Chain = P.getValue(1); + Parts[i] = P; + + // If the source register was virtual and if we know something about it, + // add an assert node. + if (!Register::isVirtualRegister(Regs[Part + i]) || + !RegisterVT.isInteger()) + continue; + + const FunctionLoweringInfo::LiveOutInfo *LOI = + FuncInfo.GetLiveOutRegInfo(Regs[Part+i]); + if (!LOI) + continue; + + unsigned RegSize = RegisterVT.getScalarSizeInBits(); + unsigned NumSignBits = LOI->NumSignBits; + unsigned NumZeroBits = LOI->Known.countMinLeadingZeros(); + + if (NumZeroBits == RegSize) { + // The current value is a zero. + // Explicitly express that as it would be easier for + // optimizations to kick in. + Parts[i] = DAG.getConstant(0, dl, RegisterVT); + continue; + } + + // FIXME: We capture more information than the dag can represent. For + // now, just use the tightest assertzext/assertsext possible. + bool isSExt; + EVT FromVT(MVT::Other); + if (NumZeroBits) { + FromVT = EVT::getIntegerVT(*DAG.getContext(), RegSize - NumZeroBits); + isSExt = false; + } else if (NumSignBits > 1) { + FromVT = + EVT::getIntegerVT(*DAG.getContext(), RegSize - NumSignBits + 1); + isSExt = true; + } else { + continue; + } + // Add an assertion node. + assert(FromVT != MVT::Other); + Parts[i] = DAG.getNode(isSExt ? ISD::AssertSext : ISD::AssertZext, dl, + RegisterVT, P, DAG.getValueType(FromVT)); + } + + Values[Value] = getCopyFromParts(DAG, dl, Parts.begin(), NumRegs, + RegisterVT, ValueVT, V, CallConv); + Part += NumRegs; + Parts.clear(); + } + + return DAG.getNode(ISD::MERGE_VALUES, dl, DAG.getVTList(ValueVTs), Values); +} + +void RegsForValue::getCopyToRegs(SDValue Val, SelectionDAG &DAG, + const SDLoc &dl, SDValue &Chain, SDValue *Flag, + const Value *V, + ISD::NodeType PreferredExtendType) const { + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + ISD::NodeType ExtendKind = PreferredExtendType; + + // Get the list of the values's legal parts. + unsigned NumRegs = Regs.size(); + SmallVector<SDValue, 8> Parts(NumRegs); + for (unsigned Value = 0, Part = 0, e = ValueVTs.size(); Value != e; ++Value) { + unsigned NumParts = RegCount[Value]; + + MVT RegisterVT = isABIMangled() ? TLI.getRegisterTypeForCallingConv( + *DAG.getContext(), + CallConv.getValue(), RegVTs[Value]) + : RegVTs[Value]; + + if (ExtendKind == ISD::ANY_EXTEND && TLI.isZExtFree(Val, RegisterVT)) + ExtendKind = ISD::ZERO_EXTEND; + + getCopyToParts(DAG, dl, Val.getValue(Val.getResNo() + Value), &Parts[Part], + NumParts, RegisterVT, V, CallConv, ExtendKind); + Part += NumParts; + } + + // Copy the parts into the registers. + SmallVector<SDValue, 8> Chains(NumRegs); + for (unsigned i = 0; i != NumRegs; ++i) { + SDValue Part; + if (!Flag) { + Part = DAG.getCopyToReg(Chain, dl, Regs[i], Parts[i]); + } else { + Part = DAG.getCopyToReg(Chain, dl, Regs[i], Parts[i], *Flag); + *Flag = Part.getValue(1); + } + + Chains[i] = Part.getValue(0); + } + + if (NumRegs == 1 || Flag) + // If NumRegs > 1 && Flag is used then the use of the last CopyToReg is + // flagged to it. That is the CopyToReg nodes and the user are considered + // a single scheduling unit. If we create a TokenFactor and return it as + // chain, then the TokenFactor is both a predecessor (operand) of the + // user as well as a successor (the TF operands are flagged to the user). + // c1, f1 = CopyToReg + // c2, f2 = CopyToReg + // c3 = TokenFactor c1, c2 + // ... + // = op c3, ..., f2 + Chain = Chains[NumRegs-1]; + else + Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Chains); +} + +void RegsForValue::AddInlineAsmOperands(unsigned Code, bool HasMatching, + unsigned MatchingIdx, const SDLoc &dl, + SelectionDAG &DAG, + std::vector<SDValue> &Ops) const { + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + + unsigned Flag = InlineAsm::getFlagWord(Code, Regs.size()); + if (HasMatching) + Flag = InlineAsm::getFlagWordForMatchingOp(Flag, MatchingIdx); + else if (!Regs.empty() && Register::isVirtualRegister(Regs.front())) { + // Put the register class of the virtual registers in the flag word. That + // way, later passes can recompute register class constraints for inline + // assembly as well as normal instructions. + // Don't do this for tied operands that can use the regclass information + // from the def. + const MachineRegisterInfo &MRI = DAG.getMachineFunction().getRegInfo(); + const TargetRegisterClass *RC = MRI.getRegClass(Regs.front()); + Flag = InlineAsm::getFlagWordForRegClass(Flag, RC->getID()); + } + + SDValue Res = DAG.getTargetConstant(Flag, dl, MVT::i32); + Ops.push_back(Res); + + if (Code == InlineAsm::Kind_Clobber) { + // Clobbers should always have a 1:1 mapping with registers, and may + // reference registers that have illegal (e.g. vector) types. Hence, we + // shouldn't try to apply any sort of splitting logic to them. + assert(Regs.size() == RegVTs.size() && Regs.size() == ValueVTs.size() && + "No 1:1 mapping from clobbers to regs?"); + unsigned SP = TLI.getStackPointerRegisterToSaveRestore(); + (void)SP; + for (unsigned I = 0, E = ValueVTs.size(); I != E; ++I) { + Ops.push_back(DAG.getRegister(Regs[I], RegVTs[I])); + assert( + (Regs[I] != SP || + DAG.getMachineFunction().getFrameInfo().hasOpaqueSPAdjustment()) && + "If we clobbered the stack pointer, MFI should know about it."); + } + return; + } + + for (unsigned Value = 0, Reg = 0, e = ValueVTs.size(); Value != e; ++Value) { + unsigned NumRegs = TLI.getNumRegisters(*DAG.getContext(), ValueVTs[Value]); + MVT RegisterVT = RegVTs[Value]; + for (unsigned i = 0; i != NumRegs; ++i) { + assert(Reg < Regs.size() && "Mismatch in # registers expected"); + unsigned TheReg = Regs[Reg++]; + Ops.push_back(DAG.getRegister(TheReg, RegisterVT)); + } + } +} + +SmallVector<std::pair<unsigned, unsigned>, 4> +RegsForValue::getRegsAndSizes() const { + SmallVector<std::pair<unsigned, unsigned>, 4> OutVec; + unsigned I = 0; + for (auto CountAndVT : zip_first(RegCount, RegVTs)) { + unsigned RegCount = std::get<0>(CountAndVT); + MVT RegisterVT = std::get<1>(CountAndVT); + unsigned RegisterSize = RegisterVT.getSizeInBits(); + for (unsigned E = I + RegCount; I != E; ++I) + OutVec.push_back(std::make_pair(Regs[I], RegisterSize)); + } + return OutVec; +} + +void SelectionDAGBuilder::init(GCFunctionInfo *gfi, AliasAnalysis *aa, + const TargetLibraryInfo *li) { + AA = aa; + GFI = gfi; + LibInfo = li; + DL = &DAG.getDataLayout(); + Context = DAG.getContext(); + LPadToCallSiteMap.clear(); + SL->init(DAG.getTargetLoweringInfo(), TM, DAG.getDataLayout()); +} + +void SelectionDAGBuilder::clear() { + NodeMap.clear(); + UnusedArgNodeMap.clear(); + PendingLoads.clear(); + PendingExports.clear(); + PendingConstrainedFP.clear(); + PendingConstrainedFPStrict.clear(); + CurInst = nullptr; + HasTailCall = false; + SDNodeOrder = LowestSDNodeOrder; + StatepointLowering.clear(); +} + +void SelectionDAGBuilder::clearDanglingDebugInfo() { + DanglingDebugInfoMap.clear(); +} + +// Update DAG root to include dependencies on Pending chains. +SDValue SelectionDAGBuilder::updateRoot(SmallVectorImpl<SDValue> &Pending) { + SDValue Root = DAG.getRoot(); + + if (Pending.empty()) + return Root; + + // Add current root to PendingChains, unless we already indirectly + // depend on it. + if (Root.getOpcode() != ISD::EntryToken) { + unsigned i = 0, e = Pending.size(); + for (; i != e; ++i) { + assert(Pending[i].getNode()->getNumOperands() > 1); + if (Pending[i].getNode()->getOperand(0) == Root) + break; // Don't add the root if we already indirectly depend on it. + } + + if (i == e) + Pending.push_back(Root); + } + + if (Pending.size() == 1) + Root = Pending[0]; + else + Root = DAG.getTokenFactor(getCurSDLoc(), Pending); + + DAG.setRoot(Root); + Pending.clear(); + return Root; +} + +SDValue SelectionDAGBuilder::getMemoryRoot() { + return updateRoot(PendingLoads); +} + +SDValue SelectionDAGBuilder::getRoot() { + // Chain up all pending constrained intrinsics together with all + // pending loads, by simply appending them to PendingLoads and + // then calling getMemoryRoot(). + PendingLoads.reserve(PendingLoads.size() + + PendingConstrainedFP.size() + + PendingConstrainedFPStrict.size()); + PendingLoads.append(PendingConstrainedFP.begin(), + PendingConstrainedFP.end()); + PendingLoads.append(PendingConstrainedFPStrict.begin(), + PendingConstrainedFPStrict.end()); + PendingConstrainedFP.clear(); + PendingConstrainedFPStrict.clear(); + return getMemoryRoot(); +} + +SDValue SelectionDAGBuilder::getControlRoot() { + // We need to emit pending fpexcept.strict constrained intrinsics, + // so append them to the PendingExports list. + PendingExports.append(PendingConstrainedFPStrict.begin(), + PendingConstrainedFPStrict.end()); + PendingConstrainedFPStrict.clear(); + return updateRoot(PendingExports); +} + +void SelectionDAGBuilder::visit(const Instruction &I) { + // Set up outgoing PHI node register values before emitting the terminator. + if (I.isTerminator()) { + HandlePHINodesInSuccessorBlocks(I.getParent()); + } + + // Increase the SDNodeOrder if dealing with a non-debug instruction. + if (!isa<DbgInfoIntrinsic>(I)) + ++SDNodeOrder; + + CurInst = &I; + + visit(I.getOpcode(), I); + + if (auto *FPMO = dyn_cast<FPMathOperator>(&I)) { + // Propagate the fast-math-flags of this IR instruction to the DAG node that + // maps to this instruction. + // TODO: We could handle all flags (nsw, etc) here. + // TODO: If an IR instruction maps to >1 node, only the final node will have + // flags set. + if (SDNode *Node = getNodeForIRValue(&I)) { + SDNodeFlags IncomingFlags; + IncomingFlags.copyFMF(*FPMO); + if (!Node->getFlags().isDefined()) + Node->setFlags(IncomingFlags); + else + Node->intersectFlagsWith(IncomingFlags); + } + } + // Constrained FP intrinsics with fpexcept.ignore should also get + // the NoFPExcept flag. + if (auto *FPI = dyn_cast<ConstrainedFPIntrinsic>(&I)) + if (FPI->getExceptionBehavior() == fp::ExceptionBehavior::ebIgnore) + if (SDNode *Node = getNodeForIRValue(&I)) { + SDNodeFlags Flags = Node->getFlags(); + Flags.setNoFPExcept(true); + Node->setFlags(Flags); + } + + if (!I.isTerminator() && !HasTailCall && + !isStatepoint(&I)) // statepoints handle their exports internally + CopyToExportRegsIfNeeded(&I); + + CurInst = nullptr; +} + +void SelectionDAGBuilder::visitPHI(const PHINode &) { + llvm_unreachable("SelectionDAGBuilder shouldn't visit PHI nodes!"); +} + +void SelectionDAGBuilder::visit(unsigned Opcode, const User &I) { + // Note: this doesn't use InstVisitor, because it has to work with + // ConstantExpr's in addition to instructions. + switch (Opcode) { + default: llvm_unreachable("Unknown instruction type encountered!"); + // Build the switch statement using the Instruction.def file. +#define HANDLE_INST(NUM, OPCODE, CLASS) \ + case Instruction::OPCODE: visit##OPCODE((const CLASS&)I); break; +#include "llvm/IR/Instruction.def" + } +} + +void SelectionDAGBuilder::dropDanglingDebugInfo(const DILocalVariable *Variable, + const DIExpression *Expr) { + auto isMatchingDbgValue = [&](DanglingDebugInfo &DDI) { + const DbgValueInst *DI = DDI.getDI(); + DIVariable *DanglingVariable = DI->getVariable(); + DIExpression *DanglingExpr = DI->getExpression(); + if (DanglingVariable == Variable && Expr->fragmentsOverlap(DanglingExpr)) { + LLVM_DEBUG(dbgs() << "Dropping dangling debug info for " << *DI << "\n"); + return true; + } + return false; + }; + + for (auto &DDIMI : DanglingDebugInfoMap) { + DanglingDebugInfoVector &DDIV = DDIMI.second; + + // If debug info is to be dropped, run it through final checks to see + // whether it can be salvaged. + for (auto &DDI : DDIV) + if (isMatchingDbgValue(DDI)) + salvageUnresolvedDbgValue(DDI); + + DDIV.erase(remove_if(DDIV, isMatchingDbgValue), DDIV.end()); + } +} + +// resolveDanglingDebugInfo - if we saw an earlier dbg_value referring to V, +// generate the debug data structures now that we've seen its definition. +void SelectionDAGBuilder::resolveDanglingDebugInfo(const Value *V, + SDValue Val) { + auto DanglingDbgInfoIt = DanglingDebugInfoMap.find(V); + if (DanglingDbgInfoIt == DanglingDebugInfoMap.end()) + return; + + DanglingDebugInfoVector &DDIV = DanglingDbgInfoIt->second; + for (auto &DDI : DDIV) { + const DbgValueInst *DI = DDI.getDI(); + assert(DI && "Ill-formed DanglingDebugInfo"); + DebugLoc dl = DDI.getdl(); + unsigned ValSDNodeOrder = Val.getNode()->getIROrder(); + unsigned DbgSDNodeOrder = DDI.getSDNodeOrder(); + DILocalVariable *Variable = DI->getVariable(); + DIExpression *Expr = DI->getExpression(); + assert(Variable->isValidLocationForIntrinsic(dl) && + "Expected inlined-at fields to agree"); + SDDbgValue *SDV; + if (Val.getNode()) { + // FIXME: I doubt that it is correct to resolve a dangling DbgValue as a + // FuncArgumentDbgValue (it would be hoisted to the function entry, and if + // we couldn't resolve it directly when examining the DbgValue intrinsic + // in the first place we should not be more successful here). Unless we + // have some test case that prove this to be correct we should avoid + // calling EmitFuncArgumentDbgValue here. + if (!EmitFuncArgumentDbgValue(V, Variable, Expr, dl, false, Val)) { + LLVM_DEBUG(dbgs() << "Resolve dangling debug info [order=" + << DbgSDNodeOrder << "] for:\n " << *DI << "\n"); + LLVM_DEBUG(dbgs() << " By mapping to:\n "; Val.dump()); + // Increase the SDNodeOrder for the DbgValue here to make sure it is + // inserted after the definition of Val when emitting the instructions + // after ISel. An alternative could be to teach + // ScheduleDAGSDNodes::EmitSchedule to delay the insertion properly. + LLVM_DEBUG(if (ValSDNodeOrder > DbgSDNodeOrder) dbgs() + << "changing SDNodeOrder from " << DbgSDNodeOrder << " to " + << ValSDNodeOrder << "\n"); + SDV = getDbgValue(Val, Variable, Expr, dl, + std::max(DbgSDNodeOrder, ValSDNodeOrder)); + DAG.AddDbgValue(SDV, Val.getNode(), false); + } else + LLVM_DEBUG(dbgs() << "Resolved dangling debug info for " << *DI + << "in EmitFuncArgumentDbgValue\n"); + } else { + LLVM_DEBUG(dbgs() << "Dropping debug info for " << *DI << "\n"); + auto Undef = + UndefValue::get(DDI.getDI()->getVariableLocation()->getType()); + auto SDV = + DAG.getConstantDbgValue(Variable, Expr, Undef, dl, DbgSDNodeOrder); + DAG.AddDbgValue(SDV, nullptr, false); + } + } + DDIV.clear(); +} + +void SelectionDAGBuilder::salvageUnresolvedDbgValue(DanglingDebugInfo &DDI) { + Value *V = DDI.getDI()->getValue(); + DILocalVariable *Var = DDI.getDI()->getVariable(); + DIExpression *Expr = DDI.getDI()->getExpression(); + DebugLoc DL = DDI.getdl(); + DebugLoc InstDL = DDI.getDI()->getDebugLoc(); + unsigned SDOrder = DDI.getSDNodeOrder(); + + // Currently we consider only dbg.value intrinsics -- we tell the salvager + // that DW_OP_stack_value is desired. + assert(isa<DbgValueInst>(DDI.getDI())); + bool StackValue = true; + + // Can this Value can be encoded without any further work? + if (handleDebugValue(V, Var, Expr, DL, InstDL, SDOrder)) + return; + + // Attempt to salvage back through as many instructions as possible. Bail if + // a non-instruction is seen, such as a constant expression or global + // variable. FIXME: Further work could recover those too. + while (isa<Instruction>(V)) { + Instruction &VAsInst = *cast<Instruction>(V); + DIExpression *NewExpr = salvageDebugInfoImpl(VAsInst, Expr, StackValue); + + // If we cannot salvage any further, and haven't yet found a suitable debug + // expression, bail out. + if (!NewExpr) + break; + + // New value and expr now represent this debuginfo. + V = VAsInst.getOperand(0); + Expr = NewExpr; + + // Some kind of simplification occurred: check whether the operand of the + // salvaged debug expression can be encoded in this DAG. + if (handleDebugValue(V, Var, Expr, DL, InstDL, SDOrder)) { + LLVM_DEBUG(dbgs() << "Salvaged debug location info for:\n " + << DDI.getDI() << "\nBy stripping back to:\n " << V); + return; + } + } + + // This was the final opportunity to salvage this debug information, and it + // couldn't be done. Place an undef DBG_VALUE at this location to terminate + // any earlier variable location. + auto Undef = UndefValue::get(DDI.getDI()->getVariableLocation()->getType()); + auto SDV = DAG.getConstantDbgValue(Var, Expr, Undef, DL, SDNodeOrder); + DAG.AddDbgValue(SDV, nullptr, false); + + LLVM_DEBUG(dbgs() << "Dropping debug value info for:\n " << DDI.getDI() + << "\n"); + LLVM_DEBUG(dbgs() << " Last seen at:\n " << *DDI.getDI()->getOperand(0) + << "\n"); +} + +bool SelectionDAGBuilder::handleDebugValue(const Value *V, DILocalVariable *Var, + DIExpression *Expr, DebugLoc dl, + DebugLoc InstDL, unsigned Order) { + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + SDDbgValue *SDV; + if (isa<ConstantInt>(V) || isa<ConstantFP>(V) || isa<UndefValue>(V) || + isa<ConstantPointerNull>(V)) { + SDV = DAG.getConstantDbgValue(Var, Expr, V, dl, SDNodeOrder); + DAG.AddDbgValue(SDV, nullptr, false); + return true; + } + + // If the Value is a frame index, we can create a FrameIndex debug value + // without relying on the DAG at all. + if (const AllocaInst *AI = dyn_cast<AllocaInst>(V)) { + auto SI = FuncInfo.StaticAllocaMap.find(AI); + if (SI != FuncInfo.StaticAllocaMap.end()) { + auto SDV = + DAG.getFrameIndexDbgValue(Var, Expr, SI->second, + /*IsIndirect*/ false, dl, SDNodeOrder); + // Do not attach the SDNodeDbgValue to an SDNode: this variable location + // is still available even if the SDNode gets optimized out. + DAG.AddDbgValue(SDV, nullptr, false); + return true; + } + } + + // Do not use getValue() in here; we don't want to generate code at + // this point if it hasn't been done yet. + SDValue N = NodeMap[V]; + if (!N.getNode() && isa<Argument>(V)) // Check unused arguments map. + N = UnusedArgNodeMap[V]; + if (N.getNode()) { + if (EmitFuncArgumentDbgValue(V, Var, Expr, dl, false, N)) + return true; + SDV = getDbgValue(N, Var, Expr, dl, SDNodeOrder); + DAG.AddDbgValue(SDV, N.getNode(), false); + return true; + } + + // Special rules apply for the first dbg.values of parameter variables in a + // function. Identify them by the fact they reference Argument Values, that + // they're parameters, and they are parameters of the current function. We + // need to let them dangle until they get an SDNode. + bool IsParamOfFunc = isa<Argument>(V) && Var->isParameter() && + !InstDL.getInlinedAt(); + if (!IsParamOfFunc) { + // The value is not used in this block yet (or it would have an SDNode). + // We still want the value to appear for the user if possible -- if it has + // an associated VReg, we can refer to that instead. + auto VMI = FuncInfo.ValueMap.find(V); + if (VMI != FuncInfo.ValueMap.end()) { + unsigned Reg = VMI->second; + // If this is a PHI node, it may be split up into several MI PHI nodes + // (in FunctionLoweringInfo::set). + RegsForValue RFV(V->getContext(), TLI, DAG.getDataLayout(), Reg, + V->getType(), None); + if (RFV.occupiesMultipleRegs()) { + unsigned Offset = 0; + unsigned BitsToDescribe = 0; + if (auto VarSize = Var->getSizeInBits()) + BitsToDescribe = *VarSize; + if (auto Fragment = Expr->getFragmentInfo()) + BitsToDescribe = Fragment->SizeInBits; + for (auto RegAndSize : RFV.getRegsAndSizes()) { + unsigned RegisterSize = RegAndSize.second; + // Bail out if all bits are described already. + if (Offset >= BitsToDescribe) + break; + unsigned FragmentSize = (Offset + RegisterSize > BitsToDescribe) + ? BitsToDescribe - Offset + : RegisterSize; + auto FragmentExpr = DIExpression::createFragmentExpression( + Expr, Offset, FragmentSize); + if (!FragmentExpr) + continue; + SDV = DAG.getVRegDbgValue(Var, *FragmentExpr, RegAndSize.first, + false, dl, SDNodeOrder); + DAG.AddDbgValue(SDV, nullptr, false); + Offset += RegisterSize; + } + } else { + SDV = DAG.getVRegDbgValue(Var, Expr, Reg, false, dl, SDNodeOrder); + DAG.AddDbgValue(SDV, nullptr, false); + } + return true; + } + } + + return false; +} + +void SelectionDAGBuilder::resolveOrClearDbgInfo() { + // Try to fixup any remaining dangling debug info -- and drop it if we can't. + for (auto &Pair : DanglingDebugInfoMap) + for (auto &DDI : Pair.second) + salvageUnresolvedDbgValue(DDI); + clearDanglingDebugInfo(); +} + +/// getCopyFromRegs - If there was virtual register allocated for the value V +/// emit CopyFromReg of the specified type Ty. Return empty SDValue() otherwise. +SDValue SelectionDAGBuilder::getCopyFromRegs(const Value *V, Type *Ty) { + DenseMap<const Value *, unsigned>::iterator It = FuncInfo.ValueMap.find(V); + SDValue Result; + + if (It != FuncInfo.ValueMap.end()) { + unsigned InReg = It->second; + + RegsForValue RFV(*DAG.getContext(), DAG.getTargetLoweringInfo(), + DAG.getDataLayout(), InReg, Ty, + None); // This is not an ABI copy. + SDValue Chain = DAG.getEntryNode(); + Result = RFV.getCopyFromRegs(DAG, FuncInfo, getCurSDLoc(), Chain, nullptr, + V); + resolveDanglingDebugInfo(V, Result); + } + + return Result; +} + +/// getValue - Return an SDValue for the given Value. +SDValue SelectionDAGBuilder::getValue(const Value *V) { + // If we already have an SDValue for this value, use it. It's important + // to do this first, so that we don't create a CopyFromReg if we already + // have a regular SDValue. + SDValue &N = NodeMap[V]; + if (N.getNode()) return N; + + // If there's a virtual register allocated and initialized for this + // value, use it. + if (SDValue copyFromReg = getCopyFromRegs(V, V->getType())) + return copyFromReg; + + // Otherwise create a new SDValue and remember it. + SDValue Val = getValueImpl(V); + NodeMap[V] = Val; + resolveDanglingDebugInfo(V, Val); + return Val; +} + +// Return true if SDValue exists for the given Value +bool SelectionDAGBuilder::findValue(const Value *V) const { + return (NodeMap.find(V) != NodeMap.end()) || + (FuncInfo.ValueMap.find(V) != FuncInfo.ValueMap.end()); +} + +/// getNonRegisterValue - Return an SDValue for the given Value, but +/// don't look in FuncInfo.ValueMap for a virtual register. +SDValue SelectionDAGBuilder::getNonRegisterValue(const Value *V) { + // If we already have an SDValue for this value, use it. + SDValue &N = NodeMap[V]; + if (N.getNode()) { + if (isa<ConstantSDNode>(N) || isa<ConstantFPSDNode>(N)) { + // Remove the debug location from the node as the node is about to be used + // in a location which may differ from the original debug location. This + // is relevant to Constant and ConstantFP nodes because they can appear + // as constant expressions inside PHI nodes. + N->setDebugLoc(DebugLoc()); + } + return N; + } + + // Otherwise create a new SDValue and remember it. + SDValue Val = getValueImpl(V); + NodeMap[V] = Val; + resolveDanglingDebugInfo(V, Val); + return Val; +} + +/// getValueImpl - Helper function for getValue and getNonRegisterValue. +/// Create an SDValue for the given value. +SDValue SelectionDAGBuilder::getValueImpl(const Value *V) { + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + + if (const Constant *C = dyn_cast<Constant>(V)) { + EVT VT = TLI.getValueType(DAG.getDataLayout(), V->getType(), true); + + if (const ConstantInt *CI = dyn_cast<ConstantInt>(C)) + return DAG.getConstant(*CI, getCurSDLoc(), VT); + + if (const GlobalValue *GV = dyn_cast<GlobalValue>(C)) + return DAG.getGlobalAddress(GV, getCurSDLoc(), VT); + + if (isa<ConstantPointerNull>(C)) { + unsigned AS = V->getType()->getPointerAddressSpace(); + return DAG.getConstant(0, getCurSDLoc(), + TLI.getPointerTy(DAG.getDataLayout(), AS)); + } + + if (const ConstantFP *CFP = dyn_cast<ConstantFP>(C)) + return DAG.getConstantFP(*CFP, getCurSDLoc(), VT); + + if (isa<UndefValue>(C) && !V->getType()->isAggregateType()) + return DAG.getUNDEF(VT); + + if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) { + visit(CE->getOpcode(), *CE); + SDValue N1 = NodeMap[V]; + assert(N1.getNode() && "visit didn't populate the NodeMap!"); + return N1; + } + + if (isa<ConstantStruct>(C) || isa<ConstantArray>(C)) { + SmallVector<SDValue, 4> Constants; + for (User::const_op_iterator OI = C->op_begin(), OE = C->op_end(); + OI != OE; ++OI) { + SDNode *Val = getValue(*OI).getNode(); + // If the operand is an empty aggregate, there are no values. + if (!Val) continue; + // Add each leaf value from the operand to the Constants list + // to form a flattened list of all the values. + for (unsigned i = 0, e = Val->getNumValues(); i != e; ++i) + Constants.push_back(SDValue(Val, i)); + } + + return DAG.getMergeValues(Constants, getCurSDLoc()); + } + + if (const ConstantDataSequential *CDS = + dyn_cast<ConstantDataSequential>(C)) { + SmallVector<SDValue, 4> Ops; + for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) { + SDNode *Val = getValue(CDS->getElementAsConstant(i)).getNode(); + // Add each leaf value from the operand to the Constants list + // to form a flattened list of all the values. + for (unsigned i = 0, e = Val->getNumValues(); i != e; ++i) + Ops.push_back(SDValue(Val, i)); + } + + if (isa<ArrayType>(CDS->getType())) + return DAG.getMergeValues(Ops, getCurSDLoc()); + return NodeMap[V] = DAG.getBuildVector(VT, getCurSDLoc(), Ops); + } + + if (C->getType()->isStructTy() || C->getType()->isArrayTy()) { + assert((isa<ConstantAggregateZero>(C) || isa<UndefValue>(C)) && + "Unknown struct or array constant!"); + + SmallVector<EVT, 4> ValueVTs; + ComputeValueVTs(TLI, DAG.getDataLayout(), C->getType(), ValueVTs); + unsigned NumElts = ValueVTs.size(); + if (NumElts == 0) + return SDValue(); // empty struct + SmallVector<SDValue, 4> Constants(NumElts); + for (unsigned i = 0; i != NumElts; ++i) { + EVT EltVT = ValueVTs[i]; + if (isa<UndefValue>(C)) + Constants[i] = DAG.getUNDEF(EltVT); + else if (EltVT.isFloatingPoint()) + Constants[i] = DAG.getConstantFP(0, getCurSDLoc(), EltVT); + else + Constants[i] = DAG.getConstant(0, getCurSDLoc(), EltVT); + } + + return DAG.getMergeValues(Constants, getCurSDLoc()); + } + + if (const BlockAddress *BA = dyn_cast<BlockAddress>(C)) + return DAG.getBlockAddress(BA, VT); + + VectorType *VecTy = cast<VectorType>(V->getType()); + unsigned NumElements = VecTy->getNumElements(); + + // Now that we know the number and type of the elements, get that number of + // elements into the Ops array based on what kind of constant it is. + SmallVector<SDValue, 16> Ops; + if (const ConstantVector *CV = dyn_cast<ConstantVector>(C)) { + for (unsigned i = 0; i != NumElements; ++i) + Ops.push_back(getValue(CV->getOperand(i))); + } else { + assert(isa<ConstantAggregateZero>(C) && "Unknown vector constant!"); + EVT EltVT = + TLI.getValueType(DAG.getDataLayout(), VecTy->getElementType()); + + SDValue Op; + if (EltVT.isFloatingPoint()) + Op = DAG.getConstantFP(0, getCurSDLoc(), EltVT); + else + Op = DAG.getConstant(0, getCurSDLoc(), EltVT); + Ops.assign(NumElements, Op); + } + + // Create a BUILD_VECTOR node. + return NodeMap[V] = DAG.getBuildVector(VT, getCurSDLoc(), Ops); + } + + // If this is a static alloca, generate it as the frameindex instead of + // computation. + if (const AllocaInst *AI = dyn_cast<AllocaInst>(V)) { + DenseMap<const AllocaInst*, int>::iterator SI = + FuncInfo.StaticAllocaMap.find(AI); + if (SI != FuncInfo.StaticAllocaMap.end()) + return DAG.getFrameIndex(SI->second, + TLI.getFrameIndexTy(DAG.getDataLayout())); + } + + // If this is an instruction which fast-isel has deferred, select it now. + if (const Instruction *Inst = dyn_cast<Instruction>(V)) { + unsigned InReg = FuncInfo.InitializeRegForValue(Inst); + + RegsForValue RFV(*DAG.getContext(), TLI, DAG.getDataLayout(), InReg, + Inst->getType(), getABIRegCopyCC(V)); + SDValue Chain = DAG.getEntryNode(); + return RFV.getCopyFromRegs(DAG, FuncInfo, getCurSDLoc(), Chain, nullptr, V); + } + + llvm_unreachable("Can't get register for value!"); +} + +void SelectionDAGBuilder::visitCatchPad(const CatchPadInst &I) { + auto Pers = classifyEHPersonality(FuncInfo.Fn->getPersonalityFn()); + bool IsMSVCCXX = Pers == EHPersonality::MSVC_CXX; + bool IsCoreCLR = Pers == EHPersonality::CoreCLR; + bool IsSEH = isAsynchronousEHPersonality(Pers); + bool IsWasmCXX = Pers == EHPersonality::Wasm_CXX; + MachineBasicBlock *CatchPadMBB = FuncInfo.MBB; + if (!IsSEH) + CatchPadMBB->setIsEHScopeEntry(); + // In MSVC C++ and CoreCLR, catchblocks are funclets and need prologues. + if (IsMSVCCXX || IsCoreCLR) + CatchPadMBB->setIsEHFuncletEntry(); + // Wasm does not need catchpads anymore + if (!IsWasmCXX) + DAG.setRoot(DAG.getNode(ISD::CATCHPAD, getCurSDLoc(), MVT::Other, + getControlRoot())); +} + +void SelectionDAGBuilder::visitCatchRet(const CatchReturnInst &I) { + // Update machine-CFG edge. + MachineBasicBlock *TargetMBB = FuncInfo.MBBMap[I.getSuccessor()]; + FuncInfo.MBB->addSuccessor(TargetMBB); + + auto Pers = classifyEHPersonality(FuncInfo.Fn->getPersonalityFn()); + bool IsSEH = isAsynchronousEHPersonality(Pers); + if (IsSEH) { + // If this is not a fall-through branch or optimizations are switched off, + // emit the branch. + if (TargetMBB != NextBlock(FuncInfo.MBB) || + TM.getOptLevel() == CodeGenOpt::None) + DAG.setRoot(DAG.getNode(ISD::BR, getCurSDLoc(), MVT::Other, + getControlRoot(), DAG.getBasicBlock(TargetMBB))); + return; + } + + // Figure out the funclet membership for the catchret's successor. + // This will be used by the FuncletLayout pass to determine how to order the + // BB's. + // A 'catchret' returns to the outer scope's color. + Value *ParentPad = I.getCatchSwitchParentPad(); + const BasicBlock *SuccessorColor; + if (isa<ConstantTokenNone>(ParentPad)) + SuccessorColor = &FuncInfo.Fn->getEntryBlock(); + else + SuccessorColor = cast<Instruction>(ParentPad)->getParent(); + assert(SuccessorColor && "No parent funclet for catchret!"); + MachineBasicBlock *SuccessorColorMBB = FuncInfo.MBBMap[SuccessorColor]; + assert(SuccessorColorMBB && "No MBB for SuccessorColor!"); + + // Create the terminator node. + SDValue Ret = DAG.getNode(ISD::CATCHRET, getCurSDLoc(), MVT::Other, + getControlRoot(), DAG.getBasicBlock(TargetMBB), + DAG.getBasicBlock(SuccessorColorMBB)); + DAG.setRoot(Ret); +} + +void SelectionDAGBuilder::visitCleanupPad(const CleanupPadInst &CPI) { + // Don't emit any special code for the cleanuppad instruction. It just marks + // the start of an EH scope/funclet. + FuncInfo.MBB->setIsEHScopeEntry(); + auto Pers = classifyEHPersonality(FuncInfo.Fn->getPersonalityFn()); + if (Pers != EHPersonality::Wasm_CXX) { + FuncInfo.MBB->setIsEHFuncletEntry(); + FuncInfo.MBB->setIsCleanupFuncletEntry(); + } +} + +// For wasm, there's alwyas a single catch pad attached to a catchswitch, and +// the control flow always stops at the single catch pad, as it does for a +// cleanup pad. In case the exception caught is not of the types the catch pad +// catches, it will be rethrown by a rethrow. +static void findWasmUnwindDestinations( + FunctionLoweringInfo &FuncInfo, const BasicBlock *EHPadBB, + BranchProbability Prob, + SmallVectorImpl<std::pair<MachineBasicBlock *, BranchProbability>> + &UnwindDests) { + while (EHPadBB) { + const Instruction *Pad = EHPadBB->getFirstNonPHI(); + if (isa<CleanupPadInst>(Pad)) { + // Stop on cleanup pads. + UnwindDests.emplace_back(FuncInfo.MBBMap[EHPadBB], Prob); + UnwindDests.back().first->setIsEHScopeEntry(); + break; + } else if (auto *CatchSwitch = dyn_cast<CatchSwitchInst>(Pad)) { + // Add the catchpad handlers to the possible destinations. We don't + // continue to the unwind destination of the catchswitch for wasm. + for (const BasicBlock *CatchPadBB : CatchSwitch->handlers()) { + UnwindDests.emplace_back(FuncInfo.MBBMap[CatchPadBB], Prob); + UnwindDests.back().first->setIsEHScopeEntry(); + } + break; + } else { + continue; + } + } +} + +/// When an invoke or a cleanupret unwinds to the next EH pad, there are +/// many places it could ultimately go. In the IR, we have a single unwind +/// destination, but in the machine CFG, we enumerate all the possible blocks. +/// This function skips over imaginary basic blocks that hold catchswitch +/// instructions, and finds all the "real" machine +/// basic block destinations. As those destinations may not be successors of +/// EHPadBB, here we also calculate the edge probability to those destinations. +/// The passed-in Prob is the edge probability to EHPadBB. +static void findUnwindDestinations( + FunctionLoweringInfo &FuncInfo, const BasicBlock *EHPadBB, + BranchProbability Prob, + SmallVectorImpl<std::pair<MachineBasicBlock *, BranchProbability>> + &UnwindDests) { + EHPersonality Personality = + classifyEHPersonality(FuncInfo.Fn->getPersonalityFn()); + bool IsMSVCCXX = Personality == EHPersonality::MSVC_CXX; + bool IsCoreCLR = Personality == EHPersonality::CoreCLR; + bool IsWasmCXX = Personality == EHPersonality::Wasm_CXX; + bool IsSEH = isAsynchronousEHPersonality(Personality); + + if (IsWasmCXX) { + findWasmUnwindDestinations(FuncInfo, EHPadBB, Prob, UnwindDests); + assert(UnwindDests.size() <= 1 && + "There should be at most one unwind destination for wasm"); + return; + } + + while (EHPadBB) { + const Instruction *Pad = EHPadBB->getFirstNonPHI(); + BasicBlock *NewEHPadBB = nullptr; + if (isa<LandingPadInst>(Pad)) { + // Stop on landingpads. They are not funclets. + UnwindDests.emplace_back(FuncInfo.MBBMap[EHPadBB], Prob); + break; + } else if (isa<CleanupPadInst>(Pad)) { + // Stop on cleanup pads. Cleanups are always funclet entries for all known + // personalities. + UnwindDests.emplace_back(FuncInfo.MBBMap[EHPadBB], Prob); + UnwindDests.back().first->setIsEHScopeEntry(); + UnwindDests.back().first->setIsEHFuncletEntry(); + break; + } else if (auto *CatchSwitch = dyn_cast<CatchSwitchInst>(Pad)) { + // Add the catchpad handlers to the possible destinations. + for (const BasicBlock *CatchPadBB : CatchSwitch->handlers()) { + UnwindDests.emplace_back(FuncInfo.MBBMap[CatchPadBB], Prob); + // For MSVC++ and the CLR, catchblocks are funclets and need prologues. + if (IsMSVCCXX || IsCoreCLR) + UnwindDests.back().first->setIsEHFuncletEntry(); + if (!IsSEH) + UnwindDests.back().first->setIsEHScopeEntry(); + } + NewEHPadBB = CatchSwitch->getUnwindDest(); + } else { + continue; + } + + BranchProbabilityInfo *BPI = FuncInfo.BPI; + if (BPI && NewEHPadBB) + Prob *= BPI->getEdgeProbability(EHPadBB, NewEHPadBB); + EHPadBB = NewEHPadBB; + } +} + +void SelectionDAGBuilder::visitCleanupRet(const CleanupReturnInst &I) { + // Update successor info. + SmallVector<std::pair<MachineBasicBlock *, BranchProbability>, 1> UnwindDests; + auto UnwindDest = I.getUnwindDest(); + BranchProbabilityInfo *BPI = FuncInfo.BPI; + BranchProbability UnwindDestProb = + (BPI && UnwindDest) + ? BPI->getEdgeProbability(FuncInfo.MBB->getBasicBlock(), UnwindDest) + : BranchProbability::getZero(); + findUnwindDestinations(FuncInfo, UnwindDest, UnwindDestProb, UnwindDests); + for (auto &UnwindDest : UnwindDests) { + UnwindDest.first->setIsEHPad(); + addSuccessorWithProb(FuncInfo.MBB, UnwindDest.first, UnwindDest.second); + } + FuncInfo.MBB->normalizeSuccProbs(); + + // Create the terminator node. + SDValue Ret = + DAG.getNode(ISD::CLEANUPRET, getCurSDLoc(), MVT::Other, getControlRoot()); + DAG.setRoot(Ret); +} + +void SelectionDAGBuilder::visitCatchSwitch(const CatchSwitchInst &CSI) { + report_fatal_error("visitCatchSwitch not yet implemented!"); +} + +void SelectionDAGBuilder::visitRet(const ReturnInst &I) { + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + auto &DL = DAG.getDataLayout(); + SDValue Chain = getControlRoot(); + SmallVector<ISD::OutputArg, 8> Outs; + SmallVector<SDValue, 8> OutVals; + + // Calls to @llvm.experimental.deoptimize don't generate a return value, so + // lower + // + // %val = call <ty> @llvm.experimental.deoptimize() + // ret <ty> %val + // + // differently. + if (I.getParent()->getTerminatingDeoptimizeCall()) { + LowerDeoptimizingReturn(); + return; + } + + if (!FuncInfo.CanLowerReturn) { + unsigned DemoteReg = FuncInfo.DemoteRegister; + const Function *F = I.getParent()->getParent(); + + // Emit a store of the return value through the virtual register. + // Leave Outs empty so that LowerReturn won't try to load return + // registers the usual way. + SmallVector<EVT, 1> PtrValueVTs; + ComputeValueVTs(TLI, DL, + F->getReturnType()->getPointerTo( + DAG.getDataLayout().getAllocaAddrSpace()), + PtrValueVTs); + + SDValue RetPtr = DAG.getCopyFromReg(DAG.getEntryNode(), getCurSDLoc(), + DemoteReg, PtrValueVTs[0]); + SDValue RetOp = getValue(I.getOperand(0)); + + SmallVector<EVT, 4> ValueVTs, MemVTs; + SmallVector<uint64_t, 4> Offsets; + ComputeValueVTs(TLI, DL, I.getOperand(0)->getType(), ValueVTs, &MemVTs, + &Offsets); + unsigned NumValues = ValueVTs.size(); + + SmallVector<SDValue, 4> Chains(NumValues); + for (unsigned i = 0; i != NumValues; ++i) { + // An aggregate return value cannot wrap around the address space, so + // offsets to its parts don't wrap either. + SDValue Ptr = DAG.getObjectPtrOffset(getCurSDLoc(), RetPtr, Offsets[i]); + + SDValue Val = RetOp.getValue(RetOp.getResNo() + i); + if (MemVTs[i] != ValueVTs[i]) + Val = DAG.getPtrExtOrTrunc(Val, getCurSDLoc(), MemVTs[i]); + Chains[i] = DAG.getStore(Chain, getCurSDLoc(), Val, + // FIXME: better loc info would be nice. + Ptr, MachinePointerInfo::getUnknownStack(DAG.getMachineFunction())); + } + + Chain = DAG.getNode(ISD::TokenFactor, getCurSDLoc(), + MVT::Other, Chains); + } else if (I.getNumOperands() != 0) { + SmallVector<EVT, 4> ValueVTs; + ComputeValueVTs(TLI, DL, I.getOperand(0)->getType(), ValueVTs); + unsigned NumValues = ValueVTs.size(); + if (NumValues) { + SDValue RetOp = getValue(I.getOperand(0)); + + const Function *F = I.getParent()->getParent(); + + bool NeedsRegBlock = TLI.functionArgumentNeedsConsecutiveRegisters( + I.getOperand(0)->getType(), F->getCallingConv(), + /*IsVarArg*/ false); + + ISD::NodeType ExtendKind = ISD::ANY_EXTEND; + if (F->getAttributes().hasAttribute(AttributeList::ReturnIndex, + Attribute::SExt)) + ExtendKind = ISD::SIGN_EXTEND; + else if (F->getAttributes().hasAttribute(AttributeList::ReturnIndex, + Attribute::ZExt)) + ExtendKind = ISD::ZERO_EXTEND; + + LLVMContext &Context = F->getContext(); + bool RetInReg = F->getAttributes().hasAttribute( + AttributeList::ReturnIndex, Attribute::InReg); + + for (unsigned j = 0; j != NumValues; ++j) { + EVT VT = ValueVTs[j]; + + if (ExtendKind != ISD::ANY_EXTEND && VT.isInteger()) + VT = TLI.getTypeForExtReturn(Context, VT, ExtendKind); + + CallingConv::ID CC = F->getCallingConv(); + + unsigned NumParts = TLI.getNumRegistersForCallingConv(Context, CC, VT); + MVT PartVT = TLI.getRegisterTypeForCallingConv(Context, CC, VT); + SmallVector<SDValue, 4> Parts(NumParts); + getCopyToParts(DAG, getCurSDLoc(), + SDValue(RetOp.getNode(), RetOp.getResNo() + j), + &Parts[0], NumParts, PartVT, &I, CC, ExtendKind); + + // 'inreg' on function refers to return value + ISD::ArgFlagsTy Flags = ISD::ArgFlagsTy(); + if (RetInReg) + Flags.setInReg(); + + if (I.getOperand(0)->getType()->isPointerTy()) { + Flags.setPointer(); + Flags.setPointerAddrSpace( + cast<PointerType>(I.getOperand(0)->getType())->getAddressSpace()); + } + + if (NeedsRegBlock) { + Flags.setInConsecutiveRegs(); + if (j == NumValues - 1) + Flags.setInConsecutiveRegsLast(); + } + + // Propagate extension type if any + if (ExtendKind == ISD::SIGN_EXTEND) + Flags.setSExt(); + else if (ExtendKind == ISD::ZERO_EXTEND) + Flags.setZExt(); + + for (unsigned i = 0; i < NumParts; ++i) { + Outs.push_back(ISD::OutputArg(Flags, Parts[i].getValueType(), + VT, /*isfixed=*/true, 0, 0)); + OutVals.push_back(Parts[i]); + } + } + } + } + + // Push in swifterror virtual register as the last element of Outs. This makes + // sure swifterror virtual register will be returned in the swifterror + // physical register. + const Function *F = I.getParent()->getParent(); + if (TLI.supportSwiftError() && + F->getAttributes().hasAttrSomewhere(Attribute::SwiftError)) { + assert(SwiftError.getFunctionArg() && "Need a swift error argument"); + ISD::ArgFlagsTy Flags = ISD::ArgFlagsTy(); + Flags.setSwiftError(); + Outs.push_back(ISD::OutputArg(Flags, EVT(TLI.getPointerTy(DL)) /*vt*/, + EVT(TLI.getPointerTy(DL)) /*argvt*/, + true /*isfixed*/, 1 /*origidx*/, + 0 /*partOffs*/)); + // Create SDNode for the swifterror virtual register. + OutVals.push_back( + DAG.getRegister(SwiftError.getOrCreateVRegUseAt( + &I, FuncInfo.MBB, SwiftError.getFunctionArg()), + EVT(TLI.getPointerTy(DL)))); + } + + bool isVarArg = DAG.getMachineFunction().getFunction().isVarArg(); + CallingConv::ID CallConv = + DAG.getMachineFunction().getFunction().getCallingConv(); + Chain = DAG.getTargetLoweringInfo().LowerReturn( + Chain, CallConv, isVarArg, Outs, OutVals, getCurSDLoc(), DAG); + + // Verify that the target's LowerReturn behaved as expected. + assert(Chain.getNode() && Chain.getValueType() == MVT::Other && + "LowerReturn didn't return a valid chain!"); + + // Update the DAG with the new chain value resulting from return lowering. + DAG.setRoot(Chain); +} + +/// CopyToExportRegsIfNeeded - If the given value has virtual registers +/// created for it, emit nodes to copy the value into the virtual +/// registers. +void SelectionDAGBuilder::CopyToExportRegsIfNeeded(const Value *V) { + // Skip empty types + if (V->getType()->isEmptyTy()) + return; + + DenseMap<const Value *, unsigned>::iterator VMI = FuncInfo.ValueMap.find(V); + if (VMI != FuncInfo.ValueMap.end()) { + assert(!V->use_empty() && "Unused value assigned virtual registers!"); + CopyValueToVirtualRegister(V, VMI->second); + } +} + +/// ExportFromCurrentBlock - If this condition isn't known to be exported from +/// the current basic block, add it to ValueMap now so that we'll get a +/// CopyTo/FromReg. +void SelectionDAGBuilder::ExportFromCurrentBlock(const Value *V) { + // No need to export constants. + if (!isa<Instruction>(V) && !isa<Argument>(V)) return; + + // Already exported? + if (FuncInfo.isExportedInst(V)) return; + + unsigned Reg = FuncInfo.InitializeRegForValue(V); + CopyValueToVirtualRegister(V, Reg); +} + +bool SelectionDAGBuilder::isExportableFromCurrentBlock(const Value *V, + const BasicBlock *FromBB) { + // The operands of the setcc have to be in this block. We don't know + // how to export them from some other block. + if (const Instruction *VI = dyn_cast<Instruction>(V)) { + // Can export from current BB. + if (VI->getParent() == FromBB) + return true; + + // Is already exported, noop. + return FuncInfo.isExportedInst(V); + } + + // If this is an argument, we can export it if the BB is the entry block or + // if it is already exported. + if (isa<Argument>(V)) { + if (FromBB == &FromBB->getParent()->getEntryBlock()) + return true; + + // Otherwise, can only export this if it is already exported. + return FuncInfo.isExportedInst(V); + } + + // Otherwise, constants can always be exported. + return true; +} + +/// Return branch probability calculated by BranchProbabilityInfo for IR blocks. +BranchProbability +SelectionDAGBuilder::getEdgeProbability(const MachineBasicBlock *Src, + const MachineBasicBlock *Dst) const { + BranchProbabilityInfo *BPI = FuncInfo.BPI; + const BasicBlock *SrcBB = Src->getBasicBlock(); + const BasicBlock *DstBB = Dst->getBasicBlock(); + if (!BPI) { + // If BPI is not available, set the default probability as 1 / N, where N is + // the number of successors. + auto SuccSize = std::max<uint32_t>(succ_size(SrcBB), 1); + return BranchProbability(1, SuccSize); + } + return BPI->getEdgeProbability(SrcBB, DstBB); +} + +void SelectionDAGBuilder::addSuccessorWithProb(MachineBasicBlock *Src, + MachineBasicBlock *Dst, + BranchProbability Prob) { + if (!FuncInfo.BPI) + Src->addSuccessorWithoutProb(Dst); + else { + if (Prob.isUnknown()) + Prob = getEdgeProbability(Src, Dst); + Src->addSuccessor(Dst, Prob); + } +} + +static bool InBlock(const Value *V, const BasicBlock *BB) { + if (const Instruction *I = dyn_cast<Instruction>(V)) + return I->getParent() == BB; + return true; +} + +/// EmitBranchForMergedCondition - Helper method for FindMergedConditions. +/// This function emits a branch and is used at the leaves of an OR or an +/// AND operator tree. +void +SelectionDAGBuilder::EmitBranchForMergedCondition(const Value *Cond, + MachineBasicBlock *TBB, + MachineBasicBlock *FBB, + MachineBasicBlock *CurBB, + MachineBasicBlock *SwitchBB, + BranchProbability TProb, + BranchProbability FProb, + bool InvertCond) { + const BasicBlock *BB = CurBB->getBasicBlock(); + + // If the leaf of the tree is a comparison, merge the condition into + // the caseblock. + if (const CmpInst *BOp = dyn_cast<CmpInst>(Cond)) { + // The operands of the cmp have to be in this block. We don't know + // how to export them from some other block. If this is the first block + // of the sequence, no exporting is needed. + if (CurBB == SwitchBB || + (isExportableFromCurrentBlock(BOp->getOperand(0), BB) && + isExportableFromCurrentBlock(BOp->getOperand(1), BB))) { + ISD::CondCode Condition; + if (const ICmpInst *IC = dyn_cast<ICmpInst>(Cond)) { + ICmpInst::Predicate Pred = + InvertCond ? IC->getInversePredicate() : IC->getPredicate(); + Condition = getICmpCondCode(Pred); + } else { + const FCmpInst *FC = cast<FCmpInst>(Cond); + FCmpInst::Predicate Pred = + InvertCond ? FC->getInversePredicate() : FC->getPredicate(); + Condition = getFCmpCondCode(Pred); + if (TM.Options.NoNaNsFPMath) + Condition = getFCmpCodeWithoutNaN(Condition); + } + + CaseBlock CB(Condition, BOp->getOperand(0), BOp->getOperand(1), nullptr, + TBB, FBB, CurBB, getCurSDLoc(), TProb, FProb); + SL->SwitchCases.push_back(CB); + return; + } + } + + // Create a CaseBlock record representing this branch. + ISD::CondCode Opc = InvertCond ? ISD::SETNE : ISD::SETEQ; + CaseBlock CB(Opc, Cond, ConstantInt::getTrue(*DAG.getContext()), + nullptr, TBB, FBB, CurBB, getCurSDLoc(), TProb, FProb); + SL->SwitchCases.push_back(CB); +} + +void SelectionDAGBuilder::FindMergedConditions(const Value *Cond, + MachineBasicBlock *TBB, + MachineBasicBlock *FBB, + MachineBasicBlock *CurBB, + MachineBasicBlock *SwitchBB, + Instruction::BinaryOps Opc, + BranchProbability TProb, + BranchProbability FProb, + bool InvertCond) { + // Skip over not part of the tree and remember to invert op and operands at + // next level. + Value *NotCond; + if (match(Cond, m_OneUse(m_Not(m_Value(NotCond)))) && + InBlock(NotCond, CurBB->getBasicBlock())) { + FindMergedConditions(NotCond, TBB, FBB, CurBB, SwitchBB, Opc, TProb, FProb, + !InvertCond); + return; + } + + const Instruction *BOp = dyn_cast<Instruction>(Cond); + // Compute the effective opcode for Cond, taking into account whether it needs + // to be inverted, e.g. + // and (not (or A, B)), C + // gets lowered as + // and (and (not A, not B), C) + unsigned BOpc = 0; + if (BOp) { + BOpc = BOp->getOpcode(); + if (InvertCond) { + if (BOpc == Instruction::And) + BOpc = Instruction::Or; + else if (BOpc == Instruction::Or) + BOpc = Instruction::And; + } + } + + // If this node is not part of the or/and tree, emit it as a branch. + if (!BOp || !(isa<BinaryOperator>(BOp) || isa<CmpInst>(BOp)) || + BOpc != unsigned(Opc) || !BOp->hasOneUse() || + BOp->getParent() != CurBB->getBasicBlock() || + !InBlock(BOp->getOperand(0), CurBB->getBasicBlock()) || + !InBlock(BOp->getOperand(1), CurBB->getBasicBlock())) { + EmitBranchForMergedCondition(Cond, TBB, FBB, CurBB, SwitchBB, + TProb, FProb, InvertCond); + return; + } + + // Create TmpBB after CurBB. + MachineFunction::iterator BBI(CurBB); + MachineFunction &MF = DAG.getMachineFunction(); + MachineBasicBlock *TmpBB = MF.CreateMachineBasicBlock(CurBB->getBasicBlock()); + CurBB->getParent()->insert(++BBI, TmpBB); + + if (Opc == Instruction::Or) { + // Codegen X | Y as: + // BB1: + // jmp_if_X TBB + // jmp TmpBB + // TmpBB: + // jmp_if_Y TBB + // jmp FBB + // + + // We have flexibility in setting Prob for BB1 and Prob for TmpBB. + // The requirement is that + // TrueProb for BB1 + (FalseProb for BB1 * TrueProb for TmpBB) + // = TrueProb for original BB. + // Assuming the original probabilities are A and B, one choice is to set + // BB1's probabilities to A/2 and A/2+B, and set TmpBB's probabilities to + // A/(1+B) and 2B/(1+B). This choice assumes that + // TrueProb for BB1 == FalseProb for BB1 * TrueProb for TmpBB. + // Another choice is to assume TrueProb for BB1 equals to TrueProb for + // TmpBB, but the math is more complicated. + + auto NewTrueProb = TProb / 2; + auto NewFalseProb = TProb / 2 + FProb; + // Emit the LHS condition. + FindMergedConditions(BOp->getOperand(0), TBB, TmpBB, CurBB, SwitchBB, Opc, + NewTrueProb, NewFalseProb, InvertCond); + + // Normalize A/2 and B to get A/(1+B) and 2B/(1+B). + SmallVector<BranchProbability, 2> Probs{TProb / 2, FProb}; + BranchProbability::normalizeProbabilities(Probs.begin(), Probs.end()); + // Emit the RHS condition into TmpBB. + FindMergedConditions(BOp->getOperand(1), TBB, FBB, TmpBB, SwitchBB, Opc, + Probs[0], Probs[1], InvertCond); + } else { + assert(Opc == Instruction::And && "Unknown merge op!"); + // Codegen X & Y as: + // BB1: + // jmp_if_X TmpBB + // jmp FBB + // TmpBB: + // jmp_if_Y TBB + // jmp FBB + // + // This requires creation of TmpBB after CurBB. + + // We have flexibility in setting Prob for BB1 and Prob for TmpBB. + // The requirement is that + // FalseProb for BB1 + (TrueProb for BB1 * FalseProb for TmpBB) + // = FalseProb for original BB. + // Assuming the original probabilities are A and B, one choice is to set + // BB1's probabilities to A+B/2 and B/2, and set TmpBB's probabilities to + // 2A/(1+A) and B/(1+A). This choice assumes that FalseProb for BB1 == + // TrueProb for BB1 * FalseProb for TmpBB. + + auto NewTrueProb = TProb + FProb / 2; + auto NewFalseProb = FProb / 2; + // Emit the LHS condition. + FindMergedConditions(BOp->getOperand(0), TmpBB, FBB, CurBB, SwitchBB, Opc, + NewTrueProb, NewFalseProb, InvertCond); + + // Normalize A and B/2 to get 2A/(1+A) and B/(1+A). + SmallVector<BranchProbability, 2> Probs{TProb, FProb / 2}; + BranchProbability::normalizeProbabilities(Probs.begin(), Probs.end()); + // Emit the RHS condition into TmpBB. + FindMergedConditions(BOp->getOperand(1), TBB, FBB, TmpBB, SwitchBB, Opc, + Probs[0], Probs[1], InvertCond); + } +} + +/// If the set of cases should be emitted as a series of branches, return true. +/// If we should emit this as a bunch of and/or'd together conditions, return +/// false. +bool +SelectionDAGBuilder::ShouldEmitAsBranches(const std::vector<CaseBlock> &Cases) { + if (Cases.size() != 2) return true; + + // If this is two comparisons of the same values or'd or and'd together, they + // will get folded into a single comparison, so don't emit two blocks. + if ((Cases[0].CmpLHS == Cases[1].CmpLHS && + Cases[0].CmpRHS == Cases[1].CmpRHS) || + (Cases[0].CmpRHS == Cases[1].CmpLHS && + Cases[0].CmpLHS == Cases[1].CmpRHS)) { + return false; + } + + // Handle: (X != null) | (Y != null) --> (X|Y) != 0 + // Handle: (X == null) & (Y == null) --> (X|Y) == 0 + if (Cases[0].CmpRHS == Cases[1].CmpRHS && + Cases[0].CC == Cases[1].CC && + isa<Constant>(Cases[0].CmpRHS) && + cast<Constant>(Cases[0].CmpRHS)->isNullValue()) { + if (Cases[0].CC == ISD::SETEQ && Cases[0].TrueBB == Cases[1].ThisBB) + return false; + if (Cases[0].CC == ISD::SETNE && Cases[0].FalseBB == Cases[1].ThisBB) + return false; + } + + return true; +} + +void SelectionDAGBuilder::visitBr(const BranchInst &I) { + MachineBasicBlock *BrMBB = FuncInfo.MBB; + + // Update machine-CFG edges. + MachineBasicBlock *Succ0MBB = FuncInfo.MBBMap[I.getSuccessor(0)]; + + if (I.isUnconditional()) { + // Update machine-CFG edges. + BrMBB->addSuccessor(Succ0MBB); + + // If this is not a fall-through branch or optimizations are switched off, + // emit the branch. + if (Succ0MBB != NextBlock(BrMBB) || TM.getOptLevel() == CodeGenOpt::None) + DAG.setRoot(DAG.getNode(ISD::BR, getCurSDLoc(), + MVT::Other, getControlRoot(), + DAG.getBasicBlock(Succ0MBB))); + + return; + } + + // If this condition is one of the special cases we handle, do special stuff + // now. + const Value *CondVal = I.getCondition(); + MachineBasicBlock *Succ1MBB = FuncInfo.MBBMap[I.getSuccessor(1)]; + + // If this is a series of conditions that are or'd or and'd together, emit + // this as a sequence of branches instead of setcc's with and/or operations. + // As long as jumps are not expensive, this should improve performance. + // For example, instead of something like: + // cmp A, B + // C = seteq + // cmp D, E + // F = setle + // or C, F + // jnz foo + // Emit: + // cmp A, B + // je foo + // cmp D, E + // jle foo + if (const BinaryOperator *BOp = dyn_cast<BinaryOperator>(CondVal)) { + Instruction::BinaryOps Opcode = BOp->getOpcode(); + if (!DAG.getTargetLoweringInfo().isJumpExpensive() && BOp->hasOneUse() && + !I.hasMetadata(LLVMContext::MD_unpredictable) && + (Opcode == Instruction::And || Opcode == Instruction::Or)) { + FindMergedConditions(BOp, Succ0MBB, Succ1MBB, BrMBB, BrMBB, + Opcode, + getEdgeProbability(BrMBB, Succ0MBB), + getEdgeProbability(BrMBB, Succ1MBB), + /*InvertCond=*/false); + // If the compares in later blocks need to use values not currently + // exported from this block, export them now. This block should always + // be the first entry. + assert(SL->SwitchCases[0].ThisBB == BrMBB && "Unexpected lowering!"); + + // Allow some cases to be rejected. + if (ShouldEmitAsBranches(SL->SwitchCases)) { + for (unsigned i = 1, e = SL->SwitchCases.size(); i != e; ++i) { + ExportFromCurrentBlock(SL->SwitchCases[i].CmpLHS); + ExportFromCurrentBlock(SL->SwitchCases[i].CmpRHS); + } + + // Emit the branch for this block. + visitSwitchCase(SL->SwitchCases[0], BrMBB); + SL->SwitchCases.erase(SL->SwitchCases.begin()); + return; + } + + // Okay, we decided not to do this, remove any inserted MBB's and clear + // SwitchCases. + for (unsigned i = 1, e = SL->SwitchCases.size(); i != e; ++i) + FuncInfo.MF->erase(SL->SwitchCases[i].ThisBB); + + SL->SwitchCases.clear(); + } + } + + // Create a CaseBlock record representing this branch. + CaseBlock CB(ISD::SETEQ, CondVal, ConstantInt::getTrue(*DAG.getContext()), + nullptr, Succ0MBB, Succ1MBB, BrMBB, getCurSDLoc()); + + // Use visitSwitchCase to actually insert the fast branch sequence for this + // cond branch. + visitSwitchCase(CB, BrMBB); +} + +/// visitSwitchCase - Emits the necessary code to represent a single node in +/// the binary search tree resulting from lowering a switch instruction. +void SelectionDAGBuilder::visitSwitchCase(CaseBlock &CB, + MachineBasicBlock *SwitchBB) { + SDValue Cond; + SDValue CondLHS = getValue(CB.CmpLHS); + SDLoc dl = CB.DL; + + if (CB.CC == ISD::SETTRUE) { + // Branch or fall through to TrueBB. + addSuccessorWithProb(SwitchBB, CB.TrueBB, CB.TrueProb); + SwitchBB->normalizeSuccProbs(); + if (CB.TrueBB != NextBlock(SwitchBB)) { + DAG.setRoot(DAG.getNode(ISD::BR, dl, MVT::Other, getControlRoot(), + DAG.getBasicBlock(CB.TrueBB))); + } + return; + } + + auto &TLI = DAG.getTargetLoweringInfo(); + EVT MemVT = TLI.getMemValueType(DAG.getDataLayout(), CB.CmpLHS->getType()); + + // Build the setcc now. + if (!CB.CmpMHS) { + // Fold "(X == true)" to X and "(X == false)" to !X to + // handle common cases produced by branch lowering. + if (CB.CmpRHS == ConstantInt::getTrue(*DAG.getContext()) && + CB.CC == ISD::SETEQ) + Cond = CondLHS; + else if (CB.CmpRHS == ConstantInt::getFalse(*DAG.getContext()) && + CB.CC == ISD::SETEQ) { + SDValue True = DAG.getConstant(1, dl, CondLHS.getValueType()); + Cond = DAG.getNode(ISD::XOR, dl, CondLHS.getValueType(), CondLHS, True); + } else { + SDValue CondRHS = getValue(CB.CmpRHS); + + // If a pointer's DAG type is larger than its memory type then the DAG + // values are zero-extended. This breaks signed comparisons so truncate + // back to the underlying type before doing the compare. + if (CondLHS.getValueType() != MemVT) { + CondLHS = DAG.getPtrExtOrTrunc(CondLHS, getCurSDLoc(), MemVT); + CondRHS = DAG.getPtrExtOrTrunc(CondRHS, getCurSDLoc(), MemVT); + } + Cond = DAG.getSetCC(dl, MVT::i1, CondLHS, CondRHS, CB.CC); + } + } else { + assert(CB.CC == ISD::SETLE && "Can handle only LE ranges now"); + + const APInt& Low = cast<ConstantInt>(CB.CmpLHS)->getValue(); + const APInt& High = cast<ConstantInt>(CB.CmpRHS)->getValue(); + + SDValue CmpOp = getValue(CB.CmpMHS); + EVT VT = CmpOp.getValueType(); + + if (cast<ConstantInt>(CB.CmpLHS)->isMinValue(true)) { + Cond = DAG.getSetCC(dl, MVT::i1, CmpOp, DAG.getConstant(High, dl, VT), + ISD::SETLE); + } else { + SDValue SUB = DAG.getNode(ISD::SUB, dl, + VT, CmpOp, DAG.getConstant(Low, dl, VT)); + Cond = DAG.getSetCC(dl, MVT::i1, SUB, + DAG.getConstant(High-Low, dl, VT), ISD::SETULE); + } + } + + // Update successor info + addSuccessorWithProb(SwitchBB, CB.TrueBB, CB.TrueProb); + // TrueBB and FalseBB are always different unless the incoming IR is + // degenerate. This only happens when running llc on weird IR. + if (CB.TrueBB != CB.FalseBB) + addSuccessorWithProb(SwitchBB, CB.FalseBB, CB.FalseProb); + SwitchBB->normalizeSuccProbs(); + + // If the lhs block is the next block, invert the condition so that we can + // fall through to the lhs instead of the rhs block. + if (CB.TrueBB == NextBlock(SwitchBB)) { + std::swap(CB.TrueBB, CB.FalseBB); + SDValue True = DAG.getConstant(1, dl, Cond.getValueType()); + Cond = DAG.getNode(ISD::XOR, dl, Cond.getValueType(), Cond, True); + } + + SDValue BrCond = DAG.getNode(ISD::BRCOND, dl, + MVT::Other, getControlRoot(), Cond, + DAG.getBasicBlock(CB.TrueBB)); + + // Insert the false branch. Do this even if it's a fall through branch, + // this makes it easier to do DAG optimizations which require inverting + // the branch condition. + BrCond = DAG.getNode(ISD::BR, dl, MVT::Other, BrCond, + DAG.getBasicBlock(CB.FalseBB)); + + DAG.setRoot(BrCond); +} + +/// visitJumpTable - Emit JumpTable node in the current MBB +void SelectionDAGBuilder::visitJumpTable(SwitchCG::JumpTable &JT) { + // Emit the code for the jump table + assert(JT.Reg != -1U && "Should lower JT Header first!"); + EVT PTy = DAG.getTargetLoweringInfo().getPointerTy(DAG.getDataLayout()); + SDValue Index = DAG.getCopyFromReg(getControlRoot(), getCurSDLoc(), + JT.Reg, PTy); + SDValue Table = DAG.getJumpTable(JT.JTI, PTy); + SDValue BrJumpTable = DAG.getNode(ISD::BR_JT, getCurSDLoc(), + MVT::Other, Index.getValue(1), + Table, Index); + DAG.setRoot(BrJumpTable); +} + +/// visitJumpTableHeader - This function emits necessary code to produce index +/// in the JumpTable from switch case. +void SelectionDAGBuilder::visitJumpTableHeader(SwitchCG::JumpTable &JT, + JumpTableHeader &JTH, + MachineBasicBlock *SwitchBB) { + SDLoc dl = getCurSDLoc(); + + // Subtract the lowest switch case value from the value being switched on. + SDValue SwitchOp = getValue(JTH.SValue); + EVT VT = SwitchOp.getValueType(); + SDValue Sub = DAG.getNode(ISD::SUB, dl, VT, SwitchOp, + DAG.getConstant(JTH.First, dl, VT)); + + // The SDNode we just created, which holds the value being switched on minus + // the smallest case value, needs to be copied to a virtual register so it + // can be used as an index into the jump table in a subsequent basic block. + // This value may be smaller or larger than the target's pointer type, and + // therefore require extension or truncating. + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + SwitchOp = DAG.getZExtOrTrunc(Sub, dl, TLI.getPointerTy(DAG.getDataLayout())); + + unsigned JumpTableReg = + FuncInfo.CreateReg(TLI.getPointerTy(DAG.getDataLayout())); + SDValue CopyTo = DAG.getCopyToReg(getControlRoot(), dl, + JumpTableReg, SwitchOp); + JT.Reg = JumpTableReg; + + if (!JTH.OmitRangeCheck) { + // Emit the range check for the jump table, and branch to the default block + // for the switch statement if the value being switched on exceeds the + // largest case in the switch. + SDValue CMP = DAG.getSetCC( + dl, TLI.getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), + Sub.getValueType()), + Sub, DAG.getConstant(JTH.Last - JTH.First, dl, VT), ISD::SETUGT); + + SDValue BrCond = DAG.getNode(ISD::BRCOND, dl, + MVT::Other, CopyTo, CMP, + DAG.getBasicBlock(JT.Default)); + + // Avoid emitting unnecessary branches to the next block. + if (JT.MBB != NextBlock(SwitchBB)) + BrCond = DAG.getNode(ISD::BR, dl, MVT::Other, BrCond, + DAG.getBasicBlock(JT.MBB)); + + DAG.setRoot(BrCond); + } else { + // Avoid emitting unnecessary branches to the next block. + if (JT.MBB != NextBlock(SwitchBB)) + DAG.setRoot(DAG.getNode(ISD::BR, dl, MVT::Other, CopyTo, + DAG.getBasicBlock(JT.MBB))); + else + DAG.setRoot(CopyTo); + } +} + +/// Create a LOAD_STACK_GUARD node, and let it carry the target specific global +/// variable if there exists one. +static SDValue getLoadStackGuard(SelectionDAG &DAG, const SDLoc &DL, + SDValue &Chain) { + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + EVT PtrTy = TLI.getPointerTy(DAG.getDataLayout()); + EVT PtrMemTy = TLI.getPointerMemTy(DAG.getDataLayout()); + MachineFunction &MF = DAG.getMachineFunction(); + Value *Global = TLI.getSDagStackGuard(*MF.getFunction().getParent()); + MachineSDNode *Node = + DAG.getMachineNode(TargetOpcode::LOAD_STACK_GUARD, DL, PtrTy, Chain); + if (Global) { + MachinePointerInfo MPInfo(Global); + auto Flags = MachineMemOperand::MOLoad | MachineMemOperand::MOInvariant | + MachineMemOperand::MODereferenceable; + MachineMemOperand *MemRef = MF.getMachineMemOperand( + MPInfo, Flags, PtrTy.getSizeInBits() / 8, DAG.getEVTAlignment(PtrTy)); + DAG.setNodeMemRefs(Node, {MemRef}); + } + if (PtrTy != PtrMemTy) + return DAG.getPtrExtOrTrunc(SDValue(Node, 0), DL, PtrMemTy); + return SDValue(Node, 0); +} + +/// Codegen a new tail for a stack protector check ParentMBB which has had its +/// tail spliced into a stack protector check success bb. +/// +/// For a high level explanation of how this fits into the stack protector +/// generation see the comment on the declaration of class +/// StackProtectorDescriptor. +void SelectionDAGBuilder::visitSPDescriptorParent(StackProtectorDescriptor &SPD, + MachineBasicBlock *ParentBB) { + + // First create the loads to the guard/stack slot for the comparison. + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + EVT PtrTy = TLI.getPointerTy(DAG.getDataLayout()); + EVT PtrMemTy = TLI.getPointerMemTy(DAG.getDataLayout()); + + MachineFrameInfo &MFI = ParentBB->getParent()->getFrameInfo(); + int FI = MFI.getStackProtectorIndex(); + + SDValue Guard; + SDLoc dl = getCurSDLoc(); + SDValue StackSlotPtr = DAG.getFrameIndex(FI, PtrTy); + const Module &M = *ParentBB->getParent()->getFunction().getParent(); + unsigned Align = DL->getPrefTypeAlignment(Type::getInt8PtrTy(M.getContext())); + + // Generate code to load the content of the guard slot. + SDValue GuardVal = DAG.getLoad( + PtrMemTy, dl, DAG.getEntryNode(), StackSlotPtr, + MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), FI), Align, + MachineMemOperand::MOVolatile); + + if (TLI.useStackGuardXorFP()) + GuardVal = TLI.emitStackGuardXorFP(DAG, GuardVal, dl); + + // Retrieve guard check function, nullptr if instrumentation is inlined. + if (const Function *GuardCheckFn = TLI.getSSPStackGuardCheck(M)) { + // The target provides a guard check function to validate the guard value. + // Generate a call to that function with the content of the guard slot as + // argument. + FunctionType *FnTy = GuardCheckFn->getFunctionType(); + assert(FnTy->getNumParams() == 1 && "Invalid function signature"); + + TargetLowering::ArgListTy Args; + TargetLowering::ArgListEntry Entry; + Entry.Node = GuardVal; + Entry.Ty = FnTy->getParamType(0); + if (GuardCheckFn->hasAttribute(1, Attribute::AttrKind::InReg)) + Entry.IsInReg = true; + Args.push_back(Entry); + + TargetLowering::CallLoweringInfo CLI(DAG); + CLI.setDebugLoc(getCurSDLoc()) + .setChain(DAG.getEntryNode()) + .setCallee(GuardCheckFn->getCallingConv(), FnTy->getReturnType(), + getValue(GuardCheckFn), std::move(Args)); + + std::pair<SDValue, SDValue> Result = TLI.LowerCallTo(CLI); + DAG.setRoot(Result.second); + return; + } + + // If useLoadStackGuardNode returns true, generate LOAD_STACK_GUARD. + // Otherwise, emit a volatile load to retrieve the stack guard value. + SDValue Chain = DAG.getEntryNode(); + if (TLI.useLoadStackGuardNode()) { + Guard = getLoadStackGuard(DAG, dl, Chain); + } else { + const Value *IRGuard = TLI.getSDagStackGuard(M); + SDValue GuardPtr = getValue(IRGuard); + + Guard = DAG.getLoad(PtrMemTy, dl, Chain, GuardPtr, + MachinePointerInfo(IRGuard, 0), Align, + MachineMemOperand::MOVolatile); + } + + // Perform the comparison via a subtract/getsetcc. + EVT VT = Guard.getValueType(); + SDValue Sub = DAG.getNode(ISD::SUB, dl, VT, Guard, GuardVal); + + SDValue Cmp = DAG.getSetCC(dl, TLI.getSetCCResultType(DAG.getDataLayout(), + *DAG.getContext(), + Sub.getValueType()), + Sub, DAG.getConstant(0, dl, VT), ISD::SETNE); + + // If the sub is not 0, then we know the guard/stackslot do not equal, so + // branch to failure MBB. + SDValue BrCond = DAG.getNode(ISD::BRCOND, dl, + MVT::Other, GuardVal.getOperand(0), + Cmp, DAG.getBasicBlock(SPD.getFailureMBB())); + // Otherwise branch to success MBB. + SDValue Br = DAG.getNode(ISD::BR, dl, + MVT::Other, BrCond, + DAG.getBasicBlock(SPD.getSuccessMBB())); + + DAG.setRoot(Br); +} + +/// Codegen the failure basic block for a stack protector check. +/// +/// A failure stack protector machine basic block consists simply of a call to +/// __stack_chk_fail(). +/// +/// For a high level explanation of how this fits into the stack protector +/// generation see the comment on the declaration of class +/// StackProtectorDescriptor. +void +SelectionDAGBuilder::visitSPDescriptorFailure(StackProtectorDescriptor &SPD) { + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + TargetLowering::MakeLibCallOptions CallOptions; + CallOptions.setDiscardResult(true); + SDValue Chain = + TLI.makeLibCall(DAG, RTLIB::STACKPROTECTOR_CHECK_FAIL, MVT::isVoid, + None, CallOptions, getCurSDLoc()).second; + // On PS4, the "return address" must still be within the calling function, + // even if it's at the very end, so emit an explicit TRAP here. + // Passing 'true' for doesNotReturn above won't generate the trap for us. + if (TM.getTargetTriple().isPS4CPU()) + Chain = DAG.getNode(ISD::TRAP, getCurSDLoc(), MVT::Other, Chain); + + DAG.setRoot(Chain); +} + +/// visitBitTestHeader - This function emits necessary code to produce value +/// suitable for "bit tests" +void SelectionDAGBuilder::visitBitTestHeader(BitTestBlock &B, + MachineBasicBlock *SwitchBB) { + SDLoc dl = getCurSDLoc(); + + // Subtract the minimum value. + SDValue SwitchOp = getValue(B.SValue); + EVT VT = SwitchOp.getValueType(); + SDValue RangeSub = + DAG.getNode(ISD::SUB, dl, VT, SwitchOp, DAG.getConstant(B.First, dl, VT)); + + // Determine the type of the test operands. + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + bool UsePtrType = false; + if (!TLI.isTypeLegal(VT)) { + UsePtrType = true; + } else { + for (unsigned i = 0, e = B.Cases.size(); i != e; ++i) + if (!isUIntN(VT.getSizeInBits(), B.Cases[i].Mask)) { + // Switch table case range are encoded into series of masks. + // Just use pointer type, it's guaranteed to fit. + UsePtrType = true; + break; + } + } + SDValue Sub = RangeSub; + if (UsePtrType) { + VT = TLI.getPointerTy(DAG.getDataLayout()); + Sub = DAG.getZExtOrTrunc(Sub, dl, VT); + } + + B.RegVT = VT.getSimpleVT(); + B.Reg = FuncInfo.CreateReg(B.RegVT); + SDValue CopyTo = DAG.getCopyToReg(getControlRoot(), dl, B.Reg, Sub); + + MachineBasicBlock* MBB = B.Cases[0].ThisBB; + + if (!B.OmitRangeCheck) + addSuccessorWithProb(SwitchBB, B.Default, B.DefaultProb); + addSuccessorWithProb(SwitchBB, MBB, B.Prob); + SwitchBB->normalizeSuccProbs(); + + SDValue Root = CopyTo; + if (!B.OmitRangeCheck) { + // Conditional branch to the default block. + SDValue RangeCmp = DAG.getSetCC(dl, + TLI.getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), + RangeSub.getValueType()), + RangeSub, DAG.getConstant(B.Range, dl, RangeSub.getValueType()), + ISD::SETUGT); + + Root = DAG.getNode(ISD::BRCOND, dl, MVT::Other, Root, RangeCmp, + DAG.getBasicBlock(B.Default)); + } + + // Avoid emitting unnecessary branches to the next block. + if (MBB != NextBlock(SwitchBB)) + Root = DAG.getNode(ISD::BR, dl, MVT::Other, Root, DAG.getBasicBlock(MBB)); + + DAG.setRoot(Root); +} + +/// visitBitTestCase - this function produces one "bit test" +void SelectionDAGBuilder::visitBitTestCase(BitTestBlock &BB, + MachineBasicBlock* NextMBB, + BranchProbability BranchProbToNext, + unsigned Reg, + BitTestCase &B, + MachineBasicBlock *SwitchBB) { + SDLoc dl = getCurSDLoc(); + MVT VT = BB.RegVT; + SDValue ShiftOp = DAG.getCopyFromReg(getControlRoot(), dl, Reg, VT); + SDValue Cmp; + unsigned PopCount = countPopulation(B.Mask); + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + if (PopCount == 1) { + // Testing for a single bit; just compare the shift count with what it + // would need to be to shift a 1 bit in that position. + Cmp = DAG.getSetCC( + dl, TLI.getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT), + ShiftOp, DAG.getConstant(countTrailingZeros(B.Mask), dl, VT), + ISD::SETEQ); + } else if (PopCount == BB.Range) { + // There is only one zero bit in the range, test for it directly. + Cmp = DAG.getSetCC( + dl, TLI.getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT), + ShiftOp, DAG.getConstant(countTrailingOnes(B.Mask), dl, VT), + ISD::SETNE); + } else { + // Make desired shift + SDValue SwitchVal = DAG.getNode(ISD::SHL, dl, VT, + DAG.getConstant(1, dl, VT), ShiftOp); + + // Emit bit tests and jumps + SDValue AndOp = DAG.getNode(ISD::AND, dl, + VT, SwitchVal, DAG.getConstant(B.Mask, dl, VT)); + Cmp = DAG.getSetCC( + dl, TLI.getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT), + AndOp, DAG.getConstant(0, dl, VT), ISD::SETNE); + } + + // The branch probability from SwitchBB to B.TargetBB is B.ExtraProb. + addSuccessorWithProb(SwitchBB, B.TargetBB, B.ExtraProb); + // The branch probability from SwitchBB to NextMBB is BranchProbToNext. + addSuccessorWithProb(SwitchBB, NextMBB, BranchProbToNext); + // It is not guaranteed that the sum of B.ExtraProb and BranchProbToNext is + // one as they are relative probabilities (and thus work more like weights), + // and hence we need to normalize them to let the sum of them become one. + SwitchBB->normalizeSuccProbs(); + + SDValue BrAnd = DAG.getNode(ISD::BRCOND, dl, + MVT::Other, getControlRoot(), + Cmp, DAG.getBasicBlock(B.TargetBB)); + + // Avoid emitting unnecessary branches to the next block. + if (NextMBB != NextBlock(SwitchBB)) + BrAnd = DAG.getNode(ISD::BR, dl, MVT::Other, BrAnd, + DAG.getBasicBlock(NextMBB)); + + DAG.setRoot(BrAnd); +} + +void SelectionDAGBuilder::visitInvoke(const InvokeInst &I) { + MachineBasicBlock *InvokeMBB = FuncInfo.MBB; + + // Retrieve successors. Look through artificial IR level blocks like + // catchswitch for successors. + MachineBasicBlock *Return = FuncInfo.MBBMap[I.getSuccessor(0)]; + const BasicBlock *EHPadBB = I.getSuccessor(1); + + // Deopt bundles are lowered in LowerCallSiteWithDeoptBundle, and we don't + // have to do anything here to lower funclet bundles. + assert(!I.hasOperandBundlesOtherThan({LLVMContext::OB_deopt, + LLVMContext::OB_funclet, + LLVMContext::OB_cfguardtarget}) && + "Cannot lower invokes with arbitrary operand bundles yet!"); + + const Value *Callee(I.getCalledValue()); + const Function *Fn = dyn_cast<Function>(Callee); + if (isa<InlineAsm>(Callee)) + visitInlineAsm(&I); + else if (Fn && Fn->isIntrinsic()) { + switch (Fn->getIntrinsicID()) { + default: + llvm_unreachable("Cannot invoke this intrinsic"); + case Intrinsic::donothing: + // Ignore invokes to @llvm.donothing: jump directly to the next BB. + break; + case Intrinsic::experimental_patchpoint_void: + case Intrinsic::experimental_patchpoint_i64: + visitPatchpoint(&I, EHPadBB); + break; + case Intrinsic::experimental_gc_statepoint: + LowerStatepoint(ImmutableStatepoint(&I), EHPadBB); + break; + case Intrinsic::wasm_rethrow_in_catch: { + // This is usually done in visitTargetIntrinsic, but this intrinsic is + // special because it can be invoked, so we manually lower it to a DAG + // node here. + SmallVector<SDValue, 8> Ops; + Ops.push_back(getRoot()); // inchain + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + Ops.push_back( + DAG.getTargetConstant(Intrinsic::wasm_rethrow_in_catch, getCurSDLoc(), + TLI.getPointerTy(DAG.getDataLayout()))); + SDVTList VTs = DAG.getVTList(ArrayRef<EVT>({MVT::Other})); // outchain + DAG.setRoot(DAG.getNode(ISD::INTRINSIC_VOID, getCurSDLoc(), VTs, Ops)); + break; + } + } + } else if (I.countOperandBundlesOfType(LLVMContext::OB_deopt)) { + // Currently we do not lower any intrinsic calls with deopt operand bundles. + // Eventually we will support lowering the @llvm.experimental.deoptimize + // intrinsic, and right now there are no plans to support other intrinsics + // with deopt state. + LowerCallSiteWithDeoptBundle(&I, getValue(Callee), EHPadBB); + } else { + LowerCallTo(&I, getValue(Callee), false, EHPadBB); + } + + // If the value of the invoke is used outside of its defining block, make it + // available as a virtual register. + // We already took care of the exported value for the statepoint instruction + // during call to the LowerStatepoint. + if (!isStatepoint(I)) { + CopyToExportRegsIfNeeded(&I); + } + + SmallVector<std::pair<MachineBasicBlock *, BranchProbability>, 1> UnwindDests; + BranchProbabilityInfo *BPI = FuncInfo.BPI; + BranchProbability EHPadBBProb = + BPI ? BPI->getEdgeProbability(InvokeMBB->getBasicBlock(), EHPadBB) + : BranchProbability::getZero(); + findUnwindDestinations(FuncInfo, EHPadBB, EHPadBBProb, UnwindDests); + + // Update successor info. + addSuccessorWithProb(InvokeMBB, Return); + for (auto &UnwindDest : UnwindDests) { + UnwindDest.first->setIsEHPad(); + addSuccessorWithProb(InvokeMBB, UnwindDest.first, UnwindDest.second); + } + InvokeMBB->normalizeSuccProbs(); + + // Drop into normal successor. + DAG.setRoot(DAG.getNode(ISD::BR, getCurSDLoc(), MVT::Other, getControlRoot(), + DAG.getBasicBlock(Return))); +} + +void SelectionDAGBuilder::visitCallBr(const CallBrInst &I) { + MachineBasicBlock *CallBrMBB = FuncInfo.MBB; + + // Deopt bundles are lowered in LowerCallSiteWithDeoptBundle, and we don't + // have to do anything here to lower funclet bundles. + assert(!I.hasOperandBundlesOtherThan( + {LLVMContext::OB_deopt, LLVMContext::OB_funclet}) && + "Cannot lower callbrs with arbitrary operand bundles yet!"); + + assert(isa<InlineAsm>(I.getCalledValue()) && + "Only know how to handle inlineasm callbr"); + visitInlineAsm(&I); + + // Retrieve successors. + MachineBasicBlock *Return = FuncInfo.MBBMap[I.getDefaultDest()]; + + // Update successor info. + addSuccessorWithProb(CallBrMBB, Return); + for (unsigned i = 0, e = I.getNumIndirectDests(); i < e; ++i) { + MachineBasicBlock *Target = FuncInfo.MBBMap[I.getIndirectDest(i)]; + addSuccessorWithProb(CallBrMBB, Target); + } + CallBrMBB->normalizeSuccProbs(); + + // Drop into default successor. + DAG.setRoot(DAG.getNode(ISD::BR, getCurSDLoc(), + MVT::Other, getControlRoot(), + DAG.getBasicBlock(Return))); +} + +void SelectionDAGBuilder::visitResume(const ResumeInst &RI) { + llvm_unreachable("SelectionDAGBuilder shouldn't visit resume instructions!"); +} + +void SelectionDAGBuilder::visitLandingPad(const LandingPadInst &LP) { + assert(FuncInfo.MBB->isEHPad() && + "Call to landingpad not in landing pad!"); + + // If there aren't registers to copy the values into (e.g., during SjLj + // exceptions), then don't bother to create these DAG nodes. + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + const Constant *PersonalityFn = FuncInfo.Fn->getPersonalityFn(); + if (TLI.getExceptionPointerRegister(PersonalityFn) == 0 && + TLI.getExceptionSelectorRegister(PersonalityFn) == 0) + return; + + // If landingpad's return type is token type, we don't create DAG nodes + // for its exception pointer and selector value. The extraction of exception + // pointer or selector value from token type landingpads is not currently + // supported. + if (LP.getType()->isTokenTy()) + return; + + SmallVector<EVT, 2> ValueVTs; + SDLoc dl = getCurSDLoc(); + ComputeValueVTs(TLI, DAG.getDataLayout(), LP.getType(), ValueVTs); + assert(ValueVTs.size() == 2 && "Only two-valued landingpads are supported"); + + // Get the two live-in registers as SDValues. The physregs have already been + // copied into virtual registers. + SDValue Ops[2]; + if (FuncInfo.ExceptionPointerVirtReg) { + Ops[0] = DAG.getZExtOrTrunc( + DAG.getCopyFromReg(DAG.getEntryNode(), dl, + FuncInfo.ExceptionPointerVirtReg, + TLI.getPointerTy(DAG.getDataLayout())), + dl, ValueVTs[0]); + } else { + Ops[0] = DAG.getConstant(0, dl, TLI.getPointerTy(DAG.getDataLayout())); + } + Ops[1] = DAG.getZExtOrTrunc( + DAG.getCopyFromReg(DAG.getEntryNode(), dl, + FuncInfo.ExceptionSelectorVirtReg, + TLI.getPointerTy(DAG.getDataLayout())), + dl, ValueVTs[1]); + + // Merge into one. + SDValue Res = DAG.getNode(ISD::MERGE_VALUES, dl, + DAG.getVTList(ValueVTs), Ops); + setValue(&LP, Res); +} + +void SelectionDAGBuilder::UpdateSplitBlock(MachineBasicBlock *First, + MachineBasicBlock *Last) { + // Update JTCases. + for (unsigned i = 0, e = SL->JTCases.size(); i != e; ++i) + if (SL->JTCases[i].first.HeaderBB == First) + SL->JTCases[i].first.HeaderBB = Last; + + // Update BitTestCases. + for (unsigned i = 0, e = SL->BitTestCases.size(); i != e; ++i) + if (SL->BitTestCases[i].Parent == First) + SL->BitTestCases[i].Parent = Last; +} + +void SelectionDAGBuilder::visitIndirectBr(const IndirectBrInst &I) { + MachineBasicBlock *IndirectBrMBB = FuncInfo.MBB; + + // Update machine-CFG edges with unique successors. + SmallSet<BasicBlock*, 32> Done; + for (unsigned i = 0, e = I.getNumSuccessors(); i != e; ++i) { + BasicBlock *BB = I.getSuccessor(i); + bool Inserted = Done.insert(BB).second; + if (!Inserted) + continue; + + MachineBasicBlock *Succ = FuncInfo.MBBMap[BB]; + addSuccessorWithProb(IndirectBrMBB, Succ); + } + IndirectBrMBB->normalizeSuccProbs(); + + DAG.setRoot(DAG.getNode(ISD::BRIND, getCurSDLoc(), + MVT::Other, getControlRoot(), + getValue(I.getAddress()))); +} + +void SelectionDAGBuilder::visitUnreachable(const UnreachableInst &I) { + if (!DAG.getTarget().Options.TrapUnreachable) + return; + + // We may be able to ignore unreachable behind a noreturn call. + if (DAG.getTarget().Options.NoTrapAfterNoreturn) { + const BasicBlock &BB = *I.getParent(); + if (&I != &BB.front()) { + BasicBlock::const_iterator PredI = + std::prev(BasicBlock::const_iterator(&I)); + if (const CallInst *Call = dyn_cast<CallInst>(&*PredI)) { + if (Call->doesNotReturn()) + return; + } + } + } + + DAG.setRoot(DAG.getNode(ISD::TRAP, getCurSDLoc(), MVT::Other, DAG.getRoot())); +} + +void SelectionDAGBuilder::visitFSub(const User &I) { + // -0.0 - X --> fneg + Type *Ty = I.getType(); + if (isa<Constant>(I.getOperand(0)) && + I.getOperand(0) == ConstantFP::getZeroValueForNegation(Ty)) { + SDValue Op2 = getValue(I.getOperand(1)); + setValue(&I, DAG.getNode(ISD::FNEG, getCurSDLoc(), + Op2.getValueType(), Op2)); + return; + } + + visitBinary(I, ISD::FSUB); +} + +/// Checks if the given instruction performs a vector reduction, in which case +/// we have the freedom to alter the elements in the result as long as the +/// reduction of them stays unchanged. +static bool isVectorReductionOp(const User *I) { + const Instruction *Inst = dyn_cast<Instruction>(I); + if (!Inst || !Inst->getType()->isVectorTy()) + return false; + + auto OpCode = Inst->getOpcode(); + switch (OpCode) { + case Instruction::Add: + case Instruction::Mul: + case Instruction::And: + case Instruction::Or: + case Instruction::Xor: + break; + case Instruction::FAdd: + case Instruction::FMul: + if (const FPMathOperator *FPOp = dyn_cast<const FPMathOperator>(Inst)) + if (FPOp->getFastMathFlags().isFast()) + break; + LLVM_FALLTHROUGH; + default: + return false; + } + + unsigned ElemNum = Inst->getType()->getVectorNumElements(); + // Ensure the reduction size is a power of 2. + if (!isPowerOf2_32(ElemNum)) + return false; + + unsigned ElemNumToReduce = ElemNum; + + // Do DFS search on the def-use chain from the given instruction. We only + // allow four kinds of operations during the search until we reach the + // instruction that extracts the first element from the vector: + // + // 1. The reduction operation of the same opcode as the given instruction. + // + // 2. PHI node. + // + // 3. ShuffleVector instruction together with a reduction operation that + // does a partial reduction. + // + // 4. ExtractElement that extracts the first element from the vector, and we + // stop searching the def-use chain here. + // + // 3 & 4 above perform a reduction on all elements of the vector. We push defs + // from 1-3 to the stack to continue the DFS. The given instruction is not + // a reduction operation if we meet any other instructions other than those + // listed above. + + SmallVector<const User *, 16> UsersToVisit{Inst}; + SmallPtrSet<const User *, 16> Visited; + bool ReduxExtracted = false; + + while (!UsersToVisit.empty()) { + auto User = UsersToVisit.back(); + UsersToVisit.pop_back(); + if (!Visited.insert(User).second) + continue; + + for (const auto *U : User->users()) { + auto Inst = dyn_cast<Instruction>(U); + if (!Inst) + return false; + + if (Inst->getOpcode() == OpCode || isa<PHINode>(U)) { + if (const FPMathOperator *FPOp = dyn_cast<const FPMathOperator>(Inst)) + if (!isa<PHINode>(FPOp) && !FPOp->getFastMathFlags().isFast()) + return false; + UsersToVisit.push_back(U); + } else if (const ShuffleVectorInst *ShufInst = + dyn_cast<ShuffleVectorInst>(U)) { + // Detect the following pattern: A ShuffleVector instruction together + // with a reduction that do partial reduction on the first and second + // ElemNumToReduce / 2 elements, and store the result in + // ElemNumToReduce / 2 elements in another vector. + + unsigned ResultElements = ShufInst->getType()->getVectorNumElements(); + if (ResultElements < ElemNum) + return false; + + if (ElemNumToReduce == 1) + return false; + if (!isa<UndefValue>(U->getOperand(1))) + return false; + for (unsigned i = 0; i < ElemNumToReduce / 2; ++i) + if (ShufInst->getMaskValue(i) != int(i + ElemNumToReduce / 2)) + return false; + for (unsigned i = ElemNumToReduce / 2; i < ElemNum; ++i) + if (ShufInst->getMaskValue(i) != -1) + return false; + + // There is only one user of this ShuffleVector instruction, which + // must be a reduction operation. + if (!U->hasOneUse()) + return false; + + auto U2 = dyn_cast<Instruction>(*U->user_begin()); + if (!U2 || U2->getOpcode() != OpCode) + return false; + + // Check operands of the reduction operation. + if ((U2->getOperand(0) == U->getOperand(0) && U2->getOperand(1) == U) || + (U2->getOperand(1) == U->getOperand(0) && U2->getOperand(0) == U)) { + UsersToVisit.push_back(U2); + ElemNumToReduce /= 2; + } else + return false; + } else if (isa<ExtractElementInst>(U)) { + // At this moment we should have reduced all elements in the vector. + if (ElemNumToReduce != 1) + return false; + + const ConstantInt *Val = dyn_cast<ConstantInt>(U->getOperand(1)); + if (!Val || !Val->isZero()) + return false; + + ReduxExtracted = true; + } else + return false; + } + } + return ReduxExtracted; +} + +void SelectionDAGBuilder::visitUnary(const User &I, unsigned Opcode) { + SDNodeFlags Flags; + + SDValue Op = getValue(I.getOperand(0)); + SDValue UnNodeValue = DAG.getNode(Opcode, getCurSDLoc(), Op.getValueType(), + Op, Flags); + setValue(&I, UnNodeValue); +} + +void SelectionDAGBuilder::visitBinary(const User &I, unsigned Opcode) { + SDNodeFlags Flags; + if (auto *OFBinOp = dyn_cast<OverflowingBinaryOperator>(&I)) { + Flags.setNoSignedWrap(OFBinOp->hasNoSignedWrap()); + Flags.setNoUnsignedWrap(OFBinOp->hasNoUnsignedWrap()); + } + if (auto *ExactOp = dyn_cast<PossiblyExactOperator>(&I)) { + Flags.setExact(ExactOp->isExact()); + } + if (isVectorReductionOp(&I)) { + Flags.setVectorReduction(true); + LLVM_DEBUG(dbgs() << "Detected a reduction operation:" << I << "\n"); + + // If no flags are set we will propagate the incoming flags, if any flags + // are set, we will intersect them with the incoming flag and so we need to + // copy the FMF flags here. + if (auto *FPOp = dyn_cast<FPMathOperator>(&I)) { + Flags.copyFMF(*FPOp); + } + } + + SDValue Op1 = getValue(I.getOperand(0)); + SDValue Op2 = getValue(I.getOperand(1)); + SDValue BinNodeValue = DAG.getNode(Opcode, getCurSDLoc(), Op1.getValueType(), + Op1, Op2, Flags); + setValue(&I, BinNodeValue); +} + +void SelectionDAGBuilder::visitShift(const User &I, unsigned Opcode) { + SDValue Op1 = getValue(I.getOperand(0)); + SDValue Op2 = getValue(I.getOperand(1)); + + EVT ShiftTy = DAG.getTargetLoweringInfo().getShiftAmountTy( + Op1.getValueType(), DAG.getDataLayout()); + + // Coerce the shift amount to the right type if we can. + if (!I.getType()->isVectorTy() && Op2.getValueType() != ShiftTy) { + unsigned ShiftSize = ShiftTy.getSizeInBits(); + unsigned Op2Size = Op2.getValueSizeInBits(); + SDLoc DL = getCurSDLoc(); + + // If the operand is smaller than the shift count type, promote it. + if (ShiftSize > Op2Size) + Op2 = DAG.getNode(ISD::ZERO_EXTEND, DL, ShiftTy, Op2); + + // If the operand is larger than the shift count type but the shift + // count type has enough bits to represent any shift value, truncate + // it now. This is a common case and it exposes the truncate to + // optimization early. + else if (ShiftSize >= Log2_32_Ceil(Op2.getValueSizeInBits())) + Op2 = DAG.getNode(ISD::TRUNCATE, DL, ShiftTy, Op2); + // Otherwise we'll need to temporarily settle for some other convenient + // type. Type legalization will make adjustments once the shiftee is split. + else + Op2 = DAG.getZExtOrTrunc(Op2, DL, MVT::i32); + } + + bool nuw = false; + bool nsw = false; + bool exact = false; + + if (Opcode == ISD::SRL || Opcode == ISD::SRA || Opcode == ISD::SHL) { + + if (const OverflowingBinaryOperator *OFBinOp = + dyn_cast<const OverflowingBinaryOperator>(&I)) { + nuw = OFBinOp->hasNoUnsignedWrap(); + nsw = OFBinOp->hasNoSignedWrap(); + } + if (const PossiblyExactOperator *ExactOp = + dyn_cast<const PossiblyExactOperator>(&I)) + exact = ExactOp->isExact(); + } + SDNodeFlags Flags; + Flags.setExact(exact); + Flags.setNoSignedWrap(nsw); + Flags.setNoUnsignedWrap(nuw); + SDValue Res = DAG.getNode(Opcode, getCurSDLoc(), Op1.getValueType(), Op1, Op2, + Flags); + setValue(&I, Res); +} + +void SelectionDAGBuilder::visitSDiv(const User &I) { + SDValue Op1 = getValue(I.getOperand(0)); + SDValue Op2 = getValue(I.getOperand(1)); + + SDNodeFlags Flags; + Flags.setExact(isa<PossiblyExactOperator>(&I) && + cast<PossiblyExactOperator>(&I)->isExact()); + setValue(&I, DAG.getNode(ISD::SDIV, getCurSDLoc(), Op1.getValueType(), Op1, + Op2, Flags)); +} + +void SelectionDAGBuilder::visitICmp(const User &I) { + ICmpInst::Predicate predicate = ICmpInst::BAD_ICMP_PREDICATE; + if (const ICmpInst *IC = dyn_cast<ICmpInst>(&I)) + predicate = IC->getPredicate(); + else if (const ConstantExpr *IC = dyn_cast<ConstantExpr>(&I)) + predicate = ICmpInst::Predicate(IC->getPredicate()); + SDValue Op1 = getValue(I.getOperand(0)); + SDValue Op2 = getValue(I.getOperand(1)); + ISD::CondCode Opcode = getICmpCondCode(predicate); + + auto &TLI = DAG.getTargetLoweringInfo(); + EVT MemVT = + TLI.getMemValueType(DAG.getDataLayout(), I.getOperand(0)->getType()); + + // If a pointer's DAG type is larger than its memory type then the DAG values + // are zero-extended. This breaks signed comparisons so truncate back to the + // underlying type before doing the compare. + if (Op1.getValueType() != MemVT) { + Op1 = DAG.getPtrExtOrTrunc(Op1, getCurSDLoc(), MemVT); + Op2 = DAG.getPtrExtOrTrunc(Op2, getCurSDLoc(), MemVT); + } + + EVT DestVT = DAG.getTargetLoweringInfo().getValueType(DAG.getDataLayout(), + I.getType()); + setValue(&I, DAG.getSetCC(getCurSDLoc(), DestVT, Op1, Op2, Opcode)); +} + +void SelectionDAGBuilder::visitFCmp(const User &I) { + FCmpInst::Predicate predicate = FCmpInst::BAD_FCMP_PREDICATE; + if (const FCmpInst *FC = dyn_cast<FCmpInst>(&I)) + predicate = FC->getPredicate(); + else if (const ConstantExpr *FC = dyn_cast<ConstantExpr>(&I)) + predicate = FCmpInst::Predicate(FC->getPredicate()); + SDValue Op1 = getValue(I.getOperand(0)); + SDValue Op2 = getValue(I.getOperand(1)); + + ISD::CondCode Condition = getFCmpCondCode(predicate); + auto *FPMO = dyn_cast<FPMathOperator>(&I); + if ((FPMO && FPMO->hasNoNaNs()) || TM.Options.NoNaNsFPMath) + Condition = getFCmpCodeWithoutNaN(Condition); + + EVT DestVT = DAG.getTargetLoweringInfo().getValueType(DAG.getDataLayout(), + I.getType()); + setValue(&I, DAG.getSetCC(getCurSDLoc(), DestVT, Op1, Op2, Condition)); +} + +// Check if the condition of the select has one use or two users that are both +// selects with the same condition. +static bool hasOnlySelectUsers(const Value *Cond) { + return llvm::all_of(Cond->users(), [](const Value *V) { + return isa<SelectInst>(V); + }); +} + +void SelectionDAGBuilder::visitSelect(const User &I) { + SmallVector<EVT, 4> ValueVTs; + ComputeValueVTs(DAG.getTargetLoweringInfo(), DAG.getDataLayout(), I.getType(), + ValueVTs); + unsigned NumValues = ValueVTs.size(); + if (NumValues == 0) return; + + SmallVector<SDValue, 4> Values(NumValues); + SDValue Cond = getValue(I.getOperand(0)); + SDValue LHSVal = getValue(I.getOperand(1)); + SDValue RHSVal = getValue(I.getOperand(2)); + auto BaseOps = {Cond}; + ISD::NodeType OpCode = Cond.getValueType().isVector() ? + ISD::VSELECT : ISD::SELECT; + + bool IsUnaryAbs = false; + + // Min/max matching is only viable if all output VTs are the same. + if (is_splat(ValueVTs)) { + EVT VT = ValueVTs[0]; + LLVMContext &Ctx = *DAG.getContext(); + auto &TLI = DAG.getTargetLoweringInfo(); + + // We care about the legality of the operation after it has been type + // legalized. + while (TLI.getTypeAction(Ctx, VT) != TargetLoweringBase::TypeLegal) + VT = TLI.getTypeToTransformTo(Ctx, VT); + + // If the vselect is legal, assume we want to leave this as a vector setcc + + // vselect. Otherwise, if this is going to be scalarized, we want to see if + // min/max is legal on the scalar type. + bool UseScalarMinMax = VT.isVector() && + !TLI.isOperationLegalOrCustom(ISD::VSELECT, VT); + + Value *LHS, *RHS; + auto SPR = matchSelectPattern(const_cast<User*>(&I), LHS, RHS); + ISD::NodeType Opc = ISD::DELETED_NODE; + switch (SPR.Flavor) { + case SPF_UMAX: Opc = ISD::UMAX; break; + case SPF_UMIN: Opc = ISD::UMIN; break; + case SPF_SMAX: Opc = ISD::SMAX; break; + case SPF_SMIN: Opc = ISD::SMIN; break; + case SPF_FMINNUM: + switch (SPR.NaNBehavior) { + case SPNB_NA: llvm_unreachable("No NaN behavior for FP op?"); + case SPNB_RETURNS_NAN: Opc = ISD::FMINIMUM; break; + case SPNB_RETURNS_OTHER: Opc = ISD::FMINNUM; break; + case SPNB_RETURNS_ANY: { + if (TLI.isOperationLegalOrCustom(ISD::FMINNUM, VT)) + Opc = ISD::FMINNUM; + else if (TLI.isOperationLegalOrCustom(ISD::FMINIMUM, VT)) + Opc = ISD::FMINIMUM; + else if (UseScalarMinMax) + Opc = TLI.isOperationLegalOrCustom(ISD::FMINNUM, VT.getScalarType()) ? + ISD::FMINNUM : ISD::FMINIMUM; + break; + } + } + break; + case SPF_FMAXNUM: + switch (SPR.NaNBehavior) { + case SPNB_NA: llvm_unreachable("No NaN behavior for FP op?"); + case SPNB_RETURNS_NAN: Opc = ISD::FMAXIMUM; break; + case SPNB_RETURNS_OTHER: Opc = ISD::FMAXNUM; break; + case SPNB_RETURNS_ANY: + + if (TLI.isOperationLegalOrCustom(ISD::FMAXNUM, VT)) + Opc = ISD::FMAXNUM; + else if (TLI.isOperationLegalOrCustom(ISD::FMAXIMUM, VT)) + Opc = ISD::FMAXIMUM; + else if (UseScalarMinMax) + Opc = TLI.isOperationLegalOrCustom(ISD::FMAXNUM, VT.getScalarType()) ? + ISD::FMAXNUM : ISD::FMAXIMUM; + break; + } + break; + case SPF_ABS: + IsUnaryAbs = true; + Opc = ISD::ABS; + break; + case SPF_NABS: + // TODO: we need to produce sub(0, abs(X)). + default: break; + } + + if (!IsUnaryAbs && Opc != ISD::DELETED_NODE && + (TLI.isOperationLegalOrCustom(Opc, VT) || + (UseScalarMinMax && + TLI.isOperationLegalOrCustom(Opc, VT.getScalarType()))) && + // If the underlying comparison instruction is used by any other + // instruction, the consumed instructions won't be destroyed, so it is + // not profitable to convert to a min/max. + hasOnlySelectUsers(cast<SelectInst>(I).getCondition())) { + OpCode = Opc; + LHSVal = getValue(LHS); + RHSVal = getValue(RHS); + BaseOps = {}; + } + + if (IsUnaryAbs) { + OpCode = Opc; + LHSVal = getValue(LHS); + BaseOps = {}; + } + } + + if (IsUnaryAbs) { + for (unsigned i = 0; i != NumValues; ++i) { + Values[i] = + DAG.getNode(OpCode, getCurSDLoc(), + LHSVal.getNode()->getValueType(LHSVal.getResNo() + i), + SDValue(LHSVal.getNode(), LHSVal.getResNo() + i)); + } + } else { + for (unsigned i = 0; i != NumValues; ++i) { + SmallVector<SDValue, 3> Ops(BaseOps.begin(), BaseOps.end()); + Ops.push_back(SDValue(LHSVal.getNode(), LHSVal.getResNo() + i)); + Ops.push_back(SDValue(RHSVal.getNode(), RHSVal.getResNo() + i)); + Values[i] = DAG.getNode( + OpCode, getCurSDLoc(), + LHSVal.getNode()->getValueType(LHSVal.getResNo() + i), Ops); + } + } + + setValue(&I, DAG.getNode(ISD::MERGE_VALUES, getCurSDLoc(), + DAG.getVTList(ValueVTs), Values)); +} + +void SelectionDAGBuilder::visitTrunc(const User &I) { + // TruncInst cannot be a no-op cast because sizeof(src) > sizeof(dest). + SDValue N = getValue(I.getOperand(0)); + EVT DestVT = DAG.getTargetLoweringInfo().getValueType(DAG.getDataLayout(), + I.getType()); + setValue(&I, DAG.getNode(ISD::TRUNCATE, getCurSDLoc(), DestVT, N)); +} + +void SelectionDAGBuilder::visitZExt(const User &I) { + // ZExt cannot be a no-op cast because sizeof(src) < sizeof(dest). + // ZExt also can't be a cast to bool for same reason. So, nothing much to do + SDValue N = getValue(I.getOperand(0)); + EVT DestVT = DAG.getTargetLoweringInfo().getValueType(DAG.getDataLayout(), + I.getType()); + setValue(&I, DAG.getNode(ISD::ZERO_EXTEND, getCurSDLoc(), DestVT, N)); +} + +void SelectionDAGBuilder::visitSExt(const User &I) { + // SExt cannot be a no-op cast because sizeof(src) < sizeof(dest). + // SExt also can't be a cast to bool for same reason. So, nothing much to do + SDValue N = getValue(I.getOperand(0)); + EVT DestVT = DAG.getTargetLoweringInfo().getValueType(DAG.getDataLayout(), + I.getType()); + setValue(&I, DAG.getNode(ISD::SIGN_EXTEND, getCurSDLoc(), DestVT, N)); +} + +void SelectionDAGBuilder::visitFPTrunc(const User &I) { + // FPTrunc is never a no-op cast, no need to check + SDValue N = getValue(I.getOperand(0)); + SDLoc dl = getCurSDLoc(); + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + EVT DestVT = TLI.getValueType(DAG.getDataLayout(), I.getType()); + setValue(&I, DAG.getNode(ISD::FP_ROUND, dl, DestVT, N, + DAG.getTargetConstant( + 0, dl, TLI.getPointerTy(DAG.getDataLayout())))); +} + +void SelectionDAGBuilder::visitFPExt(const User &I) { + // FPExt is never a no-op cast, no need to check + SDValue N = getValue(I.getOperand(0)); + EVT DestVT = DAG.getTargetLoweringInfo().getValueType(DAG.getDataLayout(), + I.getType()); + setValue(&I, DAG.getNode(ISD::FP_EXTEND, getCurSDLoc(), DestVT, N)); +} + +void SelectionDAGBuilder::visitFPToUI(const User &I) { + // FPToUI is never a no-op cast, no need to check + SDValue N = getValue(I.getOperand(0)); + EVT DestVT = DAG.getTargetLoweringInfo().getValueType(DAG.getDataLayout(), + I.getType()); + setValue(&I, DAG.getNode(ISD::FP_TO_UINT, getCurSDLoc(), DestVT, N)); +} + +void SelectionDAGBuilder::visitFPToSI(const User &I) { + // FPToSI is never a no-op cast, no need to check + SDValue N = getValue(I.getOperand(0)); + EVT DestVT = DAG.getTargetLoweringInfo().getValueType(DAG.getDataLayout(), + I.getType()); + setValue(&I, DAG.getNode(ISD::FP_TO_SINT, getCurSDLoc(), DestVT, N)); +} + +void SelectionDAGBuilder::visitUIToFP(const User &I) { + // UIToFP is never a no-op cast, no need to check + SDValue N = getValue(I.getOperand(0)); + EVT DestVT = DAG.getTargetLoweringInfo().getValueType(DAG.getDataLayout(), + I.getType()); + setValue(&I, DAG.getNode(ISD::UINT_TO_FP, getCurSDLoc(), DestVT, N)); +} + +void SelectionDAGBuilder::visitSIToFP(const User &I) { + // SIToFP is never a no-op cast, no need to check + SDValue N = getValue(I.getOperand(0)); + EVT DestVT = DAG.getTargetLoweringInfo().getValueType(DAG.getDataLayout(), + I.getType()); + setValue(&I, DAG.getNode(ISD::SINT_TO_FP, getCurSDLoc(), DestVT, N)); +} + +void SelectionDAGBuilder::visitPtrToInt(const User &I) { + // What to do depends on the size of the integer and the size of the pointer. + // We can either truncate, zero extend, or no-op, accordingly. + SDValue N = getValue(I.getOperand(0)); + auto &TLI = DAG.getTargetLoweringInfo(); + EVT DestVT = DAG.getTargetLoweringInfo().getValueType(DAG.getDataLayout(), + I.getType()); + EVT PtrMemVT = + TLI.getMemValueType(DAG.getDataLayout(), I.getOperand(0)->getType()); + N = DAG.getPtrExtOrTrunc(N, getCurSDLoc(), PtrMemVT); + N = DAG.getZExtOrTrunc(N, getCurSDLoc(), DestVT); + setValue(&I, N); +} + +void SelectionDAGBuilder::visitIntToPtr(const User &I) { + // What to do depends on the size of the integer and the size of the pointer. + // We can either truncate, zero extend, or no-op, accordingly. + SDValue N = getValue(I.getOperand(0)); + auto &TLI = DAG.getTargetLoweringInfo(); + EVT DestVT = TLI.getValueType(DAG.getDataLayout(), I.getType()); + EVT PtrMemVT = TLI.getMemValueType(DAG.getDataLayout(), I.getType()); + N = DAG.getZExtOrTrunc(N, getCurSDLoc(), PtrMemVT); + N = DAG.getPtrExtOrTrunc(N, getCurSDLoc(), DestVT); + setValue(&I, N); +} + +void SelectionDAGBuilder::visitBitCast(const User &I) { + SDValue N = getValue(I.getOperand(0)); + SDLoc dl = getCurSDLoc(); + EVT DestVT = DAG.getTargetLoweringInfo().getValueType(DAG.getDataLayout(), + I.getType()); + + // BitCast assures us that source and destination are the same size so this is + // either a BITCAST or a no-op. + if (DestVT != N.getValueType()) + setValue(&I, DAG.getNode(ISD::BITCAST, dl, + DestVT, N)); // convert types. + // Check if the original LLVM IR Operand was a ConstantInt, because getValue() + // might fold any kind of constant expression to an integer constant and that + // is not what we are looking for. Only recognize a bitcast of a genuine + // constant integer as an opaque constant. + else if(ConstantInt *C = dyn_cast<ConstantInt>(I.getOperand(0))) + setValue(&I, DAG.getConstant(C->getValue(), dl, DestVT, /*isTarget=*/false, + /*isOpaque*/true)); + else + setValue(&I, N); // noop cast. +} + +void SelectionDAGBuilder::visitAddrSpaceCast(const User &I) { + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + const Value *SV = I.getOperand(0); + SDValue N = getValue(SV); + EVT DestVT = TLI.getValueType(DAG.getDataLayout(), I.getType()); + + unsigned SrcAS = SV->getType()->getPointerAddressSpace(); + unsigned DestAS = I.getType()->getPointerAddressSpace(); + + if (!TLI.isNoopAddrSpaceCast(SrcAS, DestAS)) + N = DAG.getAddrSpaceCast(getCurSDLoc(), DestVT, N, SrcAS, DestAS); + + setValue(&I, N); +} + +void SelectionDAGBuilder::visitInsertElement(const User &I) { + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + SDValue InVec = getValue(I.getOperand(0)); + SDValue InVal = getValue(I.getOperand(1)); + SDValue InIdx = DAG.getSExtOrTrunc(getValue(I.getOperand(2)), getCurSDLoc(), + TLI.getVectorIdxTy(DAG.getDataLayout())); + setValue(&I, DAG.getNode(ISD::INSERT_VECTOR_ELT, getCurSDLoc(), + TLI.getValueType(DAG.getDataLayout(), I.getType()), + InVec, InVal, InIdx)); +} + +void SelectionDAGBuilder::visitExtractElement(const User &I) { + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + SDValue InVec = getValue(I.getOperand(0)); + SDValue InIdx = DAG.getSExtOrTrunc(getValue(I.getOperand(1)), getCurSDLoc(), + TLI.getVectorIdxTy(DAG.getDataLayout())); + setValue(&I, DAG.getNode(ISD::EXTRACT_VECTOR_ELT, getCurSDLoc(), + TLI.getValueType(DAG.getDataLayout(), I.getType()), + InVec, InIdx)); +} + +void SelectionDAGBuilder::visitShuffleVector(const User &I) { + SDValue Src1 = getValue(I.getOperand(0)); + SDValue Src2 = getValue(I.getOperand(1)); + Constant *MaskV = cast<Constant>(I.getOperand(2)); + SDLoc DL = getCurSDLoc(); + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + EVT VT = TLI.getValueType(DAG.getDataLayout(), I.getType()); + EVT SrcVT = Src1.getValueType(); + unsigned SrcNumElts = SrcVT.getVectorNumElements(); + + if (MaskV->isNullValue() && VT.isScalableVector()) { + // Canonical splat form of first element of first input vector. + SDValue FirstElt = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, DL, + SrcVT.getScalarType(), Src1, + DAG.getConstant(0, DL, + TLI.getVectorIdxTy(DAG.getDataLayout()))); + setValue(&I, DAG.getNode(ISD::SPLAT_VECTOR, DL, VT, FirstElt)); + return; + } + + // For now, we only handle splats for scalable vectors. + // The DAGCombiner will perform a BUILD_VECTOR -> SPLAT_VECTOR transformation + // for targets that support a SPLAT_VECTOR for non-scalable vector types. + assert(!VT.isScalableVector() && "Unsupported scalable vector shuffle"); + + SmallVector<int, 8> Mask; + ShuffleVectorInst::getShuffleMask(MaskV, Mask); + unsigned MaskNumElts = Mask.size(); + + if (SrcNumElts == MaskNumElts) { + setValue(&I, DAG.getVectorShuffle(VT, DL, Src1, Src2, Mask)); + return; + } + + // Normalize the shuffle vector since mask and vector length don't match. + if (SrcNumElts < MaskNumElts) { + // Mask is longer than the source vectors. We can use concatenate vector to + // make the mask and vectors lengths match. + + if (MaskNumElts % SrcNumElts == 0) { + // Mask length is a multiple of the source vector length. + // Check if the shuffle is some kind of concatenation of the input + // vectors. + unsigned NumConcat = MaskNumElts / SrcNumElts; + bool IsConcat = true; + SmallVector<int, 8> ConcatSrcs(NumConcat, -1); + for (unsigned i = 0; i != MaskNumElts; ++i) { + int Idx = Mask[i]; + if (Idx < 0) + continue; + // Ensure the indices in each SrcVT sized piece are sequential and that + // the same source is used for the whole piece. + if ((Idx % SrcNumElts != (i % SrcNumElts)) || + (ConcatSrcs[i / SrcNumElts] >= 0 && + ConcatSrcs[i / SrcNumElts] != (int)(Idx / SrcNumElts))) { + IsConcat = false; + break; + } + // Remember which source this index came from. + ConcatSrcs[i / SrcNumElts] = Idx / SrcNumElts; + } + + // The shuffle is concatenating multiple vectors together. Just emit + // a CONCAT_VECTORS operation. + if (IsConcat) { + SmallVector<SDValue, 8> ConcatOps; + for (auto Src : ConcatSrcs) { + if (Src < 0) + ConcatOps.push_back(DAG.getUNDEF(SrcVT)); + else if (Src == 0) + ConcatOps.push_back(Src1); + else + ConcatOps.push_back(Src2); + } + setValue(&I, DAG.getNode(ISD::CONCAT_VECTORS, DL, VT, ConcatOps)); + return; + } + } + + unsigned PaddedMaskNumElts = alignTo(MaskNumElts, SrcNumElts); + unsigned NumConcat = PaddedMaskNumElts / SrcNumElts; + EVT PaddedVT = EVT::getVectorVT(*DAG.getContext(), VT.getScalarType(), + PaddedMaskNumElts); + + // Pad both vectors with undefs to make them the same length as the mask. + SDValue UndefVal = DAG.getUNDEF(SrcVT); + + SmallVector<SDValue, 8> MOps1(NumConcat, UndefVal); + SmallVector<SDValue, 8> MOps2(NumConcat, UndefVal); + MOps1[0] = Src1; + MOps2[0] = Src2; + + Src1 = DAG.getNode(ISD::CONCAT_VECTORS, DL, PaddedVT, MOps1); + Src2 = DAG.getNode(ISD::CONCAT_VECTORS, DL, PaddedVT, MOps2); + + // Readjust mask for new input vector length. + SmallVector<int, 8> MappedOps(PaddedMaskNumElts, -1); + for (unsigned i = 0; i != MaskNumElts; ++i) { + int Idx = Mask[i]; + if (Idx >= (int)SrcNumElts) + Idx -= SrcNumElts - PaddedMaskNumElts; + MappedOps[i] = Idx; + } + + SDValue Result = DAG.getVectorShuffle(PaddedVT, DL, Src1, Src2, MappedOps); + + // If the concatenated vector was padded, extract a subvector with the + // correct number of elements. + if (MaskNumElts != PaddedMaskNumElts) + Result = DAG.getNode( + ISD::EXTRACT_SUBVECTOR, DL, VT, Result, + DAG.getConstant(0, DL, TLI.getVectorIdxTy(DAG.getDataLayout()))); + + setValue(&I, Result); + return; + } + + if (SrcNumElts > MaskNumElts) { + // Analyze the access pattern of the vector to see if we can extract + // two subvectors and do the shuffle. + int StartIdx[2] = { -1, -1 }; // StartIdx to extract from + bool CanExtract = true; + for (int Idx : Mask) { + unsigned Input = 0; + if (Idx < 0) + continue; + + if (Idx >= (int)SrcNumElts) { + Input = 1; + Idx -= SrcNumElts; + } + + // If all the indices come from the same MaskNumElts sized portion of + // the sources we can use extract. Also make sure the extract wouldn't + // extract past the end of the source. + int NewStartIdx = alignDown(Idx, MaskNumElts); + if (NewStartIdx + MaskNumElts > SrcNumElts || + (StartIdx[Input] >= 0 && StartIdx[Input] != NewStartIdx)) + CanExtract = false; + // Make sure we always update StartIdx as we use it to track if all + // elements are undef. + StartIdx[Input] = NewStartIdx; + } + + if (StartIdx[0] < 0 && StartIdx[1] < 0) { + setValue(&I, DAG.getUNDEF(VT)); // Vectors are not used. + return; + } + if (CanExtract) { + // Extract appropriate subvector and generate a vector shuffle + for (unsigned Input = 0; Input < 2; ++Input) { + SDValue &Src = Input == 0 ? Src1 : Src2; + if (StartIdx[Input] < 0) + Src = DAG.getUNDEF(VT); + else { + Src = DAG.getNode( + ISD::EXTRACT_SUBVECTOR, DL, VT, Src, + DAG.getConstant(StartIdx[Input], DL, + TLI.getVectorIdxTy(DAG.getDataLayout()))); + } + } + + // Calculate new mask. + SmallVector<int, 8> MappedOps(Mask.begin(), Mask.end()); + for (int &Idx : MappedOps) { + if (Idx >= (int)SrcNumElts) + Idx -= SrcNumElts + StartIdx[1] - MaskNumElts; + else if (Idx >= 0) + Idx -= StartIdx[0]; + } + + setValue(&I, DAG.getVectorShuffle(VT, DL, Src1, Src2, MappedOps)); + return; + } + } + + // We can't use either concat vectors or extract subvectors so fall back to + // replacing the shuffle with extract and build vector. + // to insert and build vector. + EVT EltVT = VT.getVectorElementType(); + EVT IdxVT = TLI.getVectorIdxTy(DAG.getDataLayout()); + SmallVector<SDValue,8> Ops; + for (int Idx : Mask) { + SDValue Res; + + if (Idx < 0) { + Res = DAG.getUNDEF(EltVT); + } else { + SDValue &Src = Idx < (int)SrcNumElts ? Src1 : Src2; + if (Idx >= (int)SrcNumElts) Idx -= SrcNumElts; + + Res = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, DL, + EltVT, Src, DAG.getConstant(Idx, DL, IdxVT)); + } + + Ops.push_back(Res); + } + + setValue(&I, DAG.getBuildVector(VT, DL, Ops)); +} + +void SelectionDAGBuilder::visitInsertValue(const User &I) { + ArrayRef<unsigned> Indices; + if (const InsertValueInst *IV = dyn_cast<InsertValueInst>(&I)) + Indices = IV->getIndices(); + else + Indices = cast<ConstantExpr>(&I)->getIndices(); + + const Value *Op0 = I.getOperand(0); + const Value *Op1 = I.getOperand(1); + Type *AggTy = I.getType(); + Type *ValTy = Op1->getType(); + bool IntoUndef = isa<UndefValue>(Op0); + bool FromUndef = isa<UndefValue>(Op1); + + unsigned LinearIndex = ComputeLinearIndex(AggTy, Indices); + + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + SmallVector<EVT, 4> AggValueVTs; + ComputeValueVTs(TLI, DAG.getDataLayout(), AggTy, AggValueVTs); + SmallVector<EVT, 4> ValValueVTs; + ComputeValueVTs(TLI, DAG.getDataLayout(), ValTy, ValValueVTs); + + unsigned NumAggValues = AggValueVTs.size(); + unsigned NumValValues = ValValueVTs.size(); + SmallVector<SDValue, 4> Values(NumAggValues); + + // Ignore an insertvalue that produces an empty object + if (!NumAggValues) { + setValue(&I, DAG.getUNDEF(MVT(MVT::Other))); + return; + } + + SDValue Agg = getValue(Op0); + unsigned i = 0; + // Copy the beginning value(s) from the original aggregate. + for (; i != LinearIndex; ++i) + Values[i] = IntoUndef ? DAG.getUNDEF(AggValueVTs[i]) : + SDValue(Agg.getNode(), Agg.getResNo() + i); + // Copy values from the inserted value(s). + if (NumValValues) { + SDValue Val = getValue(Op1); + for (; i != LinearIndex + NumValValues; ++i) + Values[i] = FromUndef ? DAG.getUNDEF(AggValueVTs[i]) : + SDValue(Val.getNode(), Val.getResNo() + i - LinearIndex); + } + // Copy remaining value(s) from the original aggregate. + for (; i != NumAggValues; ++i) + Values[i] = IntoUndef ? DAG.getUNDEF(AggValueVTs[i]) : + SDValue(Agg.getNode(), Agg.getResNo() + i); + + setValue(&I, DAG.getNode(ISD::MERGE_VALUES, getCurSDLoc(), + DAG.getVTList(AggValueVTs), Values)); +} + +void SelectionDAGBuilder::visitExtractValue(const User &I) { + ArrayRef<unsigned> Indices; + if (const ExtractValueInst *EV = dyn_cast<ExtractValueInst>(&I)) + Indices = EV->getIndices(); + else + Indices = cast<ConstantExpr>(&I)->getIndices(); + + const Value *Op0 = I.getOperand(0); + Type *AggTy = Op0->getType(); + Type *ValTy = I.getType(); + bool OutOfUndef = isa<UndefValue>(Op0); + + unsigned LinearIndex = ComputeLinearIndex(AggTy, Indices); + + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + SmallVector<EVT, 4> ValValueVTs; + ComputeValueVTs(TLI, DAG.getDataLayout(), ValTy, ValValueVTs); + + unsigned NumValValues = ValValueVTs.size(); + + // Ignore a extractvalue that produces an empty object + if (!NumValValues) { + setValue(&I, DAG.getUNDEF(MVT(MVT::Other))); + return; + } + + SmallVector<SDValue, 4> Values(NumValValues); + + SDValue Agg = getValue(Op0); + // Copy out the selected value(s). + for (unsigned i = LinearIndex; i != LinearIndex + NumValValues; ++i) + Values[i - LinearIndex] = + OutOfUndef ? + DAG.getUNDEF(Agg.getNode()->getValueType(Agg.getResNo() + i)) : + SDValue(Agg.getNode(), Agg.getResNo() + i); + + setValue(&I, DAG.getNode(ISD::MERGE_VALUES, getCurSDLoc(), + DAG.getVTList(ValValueVTs), Values)); +} + +void SelectionDAGBuilder::visitGetElementPtr(const User &I) { + Value *Op0 = I.getOperand(0); + // Note that the pointer operand may be a vector of pointers. Take the scalar + // element which holds a pointer. + unsigned AS = Op0->getType()->getScalarType()->getPointerAddressSpace(); + SDValue N = getValue(Op0); + SDLoc dl = getCurSDLoc(); + auto &TLI = DAG.getTargetLoweringInfo(); + MVT PtrTy = TLI.getPointerTy(DAG.getDataLayout(), AS); + MVT PtrMemTy = TLI.getPointerMemTy(DAG.getDataLayout(), AS); + + // Normalize Vector GEP - all scalar operands should be converted to the + // splat vector. + unsigned VectorWidth = I.getType()->isVectorTy() ? + I.getType()->getVectorNumElements() : 0; + + if (VectorWidth && !N.getValueType().isVector()) { + LLVMContext &Context = *DAG.getContext(); + EVT VT = EVT::getVectorVT(Context, N.getValueType(), VectorWidth); + N = DAG.getSplatBuildVector(VT, dl, N); + } + + for (gep_type_iterator GTI = gep_type_begin(&I), E = gep_type_end(&I); + GTI != E; ++GTI) { + const Value *Idx = GTI.getOperand(); + if (StructType *StTy = GTI.getStructTypeOrNull()) { + unsigned Field = cast<Constant>(Idx)->getUniqueInteger().getZExtValue(); + if (Field) { + // N = N + Offset + uint64_t Offset = DL->getStructLayout(StTy)->getElementOffset(Field); + + // In an inbounds GEP with an offset that is nonnegative even when + // interpreted as signed, assume there is no unsigned overflow. + SDNodeFlags Flags; + if (int64_t(Offset) >= 0 && cast<GEPOperator>(I).isInBounds()) + Flags.setNoUnsignedWrap(true); + + N = DAG.getNode(ISD::ADD, dl, N.getValueType(), N, + DAG.getConstant(Offset, dl, N.getValueType()), Flags); + } + } else { + unsigned IdxSize = DAG.getDataLayout().getIndexSizeInBits(AS); + MVT IdxTy = MVT::getIntegerVT(IdxSize); + APInt ElementSize(IdxSize, DL->getTypeAllocSize(GTI.getIndexedType())); + + // If this is a scalar constant or a splat vector of constants, + // handle it quickly. + const auto *C = dyn_cast<Constant>(Idx); + if (C && isa<VectorType>(C->getType())) + C = C->getSplatValue(); + + if (const auto *CI = dyn_cast_or_null<ConstantInt>(C)) { + if (CI->isZero()) + continue; + APInt Offs = ElementSize * CI->getValue().sextOrTrunc(IdxSize); + LLVMContext &Context = *DAG.getContext(); + SDValue OffsVal = VectorWidth ? + DAG.getConstant(Offs, dl, EVT::getVectorVT(Context, IdxTy, VectorWidth)) : + DAG.getConstant(Offs, dl, IdxTy); + + // In an inbounds GEP with an offset that is nonnegative even when + // interpreted as signed, assume there is no unsigned overflow. + SDNodeFlags Flags; + if (Offs.isNonNegative() && cast<GEPOperator>(I).isInBounds()) + Flags.setNoUnsignedWrap(true); + + OffsVal = DAG.getSExtOrTrunc(OffsVal, dl, N.getValueType()); + + N = DAG.getNode(ISD::ADD, dl, N.getValueType(), N, OffsVal, Flags); + continue; + } + + // N = N + Idx * ElementSize; + SDValue IdxN = getValue(Idx); + + if (!IdxN.getValueType().isVector() && VectorWidth) { + EVT VT = EVT::getVectorVT(*Context, IdxN.getValueType(), VectorWidth); + IdxN = DAG.getSplatBuildVector(VT, dl, IdxN); + } + + // If the index is smaller or larger than intptr_t, truncate or extend + // it. + IdxN = DAG.getSExtOrTrunc(IdxN, dl, N.getValueType()); + + // If this is a multiply by a power of two, turn it into a shl + // immediately. This is a very common case. + if (ElementSize != 1) { + if (ElementSize.isPowerOf2()) { + unsigned Amt = ElementSize.logBase2(); + IdxN = DAG.getNode(ISD::SHL, dl, + N.getValueType(), IdxN, + DAG.getConstant(Amt, dl, IdxN.getValueType())); + } else { + SDValue Scale = DAG.getConstant(ElementSize.getZExtValue(), dl, + IdxN.getValueType()); + IdxN = DAG.getNode(ISD::MUL, dl, + N.getValueType(), IdxN, Scale); + } + } + + N = DAG.getNode(ISD::ADD, dl, + N.getValueType(), N, IdxN); + } + } + + if (PtrMemTy != PtrTy && !cast<GEPOperator>(I).isInBounds()) + N = DAG.getPtrExtendInReg(N, dl, PtrMemTy); + + setValue(&I, N); +} + +void SelectionDAGBuilder::visitAlloca(const AllocaInst &I) { + // If this is a fixed sized alloca in the entry block of the function, + // allocate it statically on the stack. + if (FuncInfo.StaticAllocaMap.count(&I)) + return; // getValue will auto-populate this. + + SDLoc dl = getCurSDLoc(); + Type *Ty = I.getAllocatedType(); + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + auto &DL = DAG.getDataLayout(); + uint64_t TySize = DL.getTypeAllocSize(Ty); + unsigned Align = + std::max((unsigned)DL.getPrefTypeAlignment(Ty), I.getAlignment()); + + SDValue AllocSize = getValue(I.getArraySize()); + + EVT IntPtr = TLI.getPointerTy(DAG.getDataLayout(), DL.getAllocaAddrSpace()); + if (AllocSize.getValueType() != IntPtr) + AllocSize = DAG.getZExtOrTrunc(AllocSize, dl, IntPtr); + + AllocSize = DAG.getNode(ISD::MUL, dl, IntPtr, + AllocSize, + DAG.getConstant(TySize, dl, IntPtr)); + + // Handle alignment. If the requested alignment is less than or equal to + // the stack alignment, ignore it. If the size is greater than or equal to + // the stack alignment, we note this in the DYNAMIC_STACKALLOC node. + unsigned StackAlign = + DAG.getSubtarget().getFrameLowering()->getStackAlignment(); + if (Align <= StackAlign) + Align = 0; + + // Round the size of the allocation up to the stack alignment size + // by add SA-1 to the size. This doesn't overflow because we're computing + // an address inside an alloca. + SDNodeFlags Flags; + Flags.setNoUnsignedWrap(true); + AllocSize = DAG.getNode(ISD::ADD, dl, AllocSize.getValueType(), AllocSize, + DAG.getConstant(StackAlign - 1, dl, IntPtr), Flags); + + // Mask out the low bits for alignment purposes. + AllocSize = + DAG.getNode(ISD::AND, dl, AllocSize.getValueType(), AllocSize, + DAG.getConstant(~(uint64_t)(StackAlign - 1), dl, IntPtr)); + + SDValue Ops[] = {getRoot(), AllocSize, DAG.getConstant(Align, dl, IntPtr)}; + SDVTList VTs = DAG.getVTList(AllocSize.getValueType(), MVT::Other); + SDValue DSA = DAG.getNode(ISD::DYNAMIC_STACKALLOC, dl, VTs, Ops); + setValue(&I, DSA); + DAG.setRoot(DSA.getValue(1)); + + assert(FuncInfo.MF->getFrameInfo().hasVarSizedObjects()); +} + +void SelectionDAGBuilder::visitLoad(const LoadInst &I) { + if (I.isAtomic()) + return visitAtomicLoad(I); + + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + const Value *SV = I.getOperand(0); + if (TLI.supportSwiftError()) { + // Swifterror values can come from either a function parameter with + // swifterror attribute or an alloca with swifterror attribute. + if (const Argument *Arg = dyn_cast<Argument>(SV)) { + if (Arg->hasSwiftErrorAttr()) + return visitLoadFromSwiftError(I); + } + + if (const AllocaInst *Alloca = dyn_cast<AllocaInst>(SV)) { + if (Alloca->isSwiftError()) + return visitLoadFromSwiftError(I); + } + } + + SDValue Ptr = getValue(SV); + + Type *Ty = I.getType(); + + bool isVolatile = I.isVolatile(); + bool isNonTemporal = I.hasMetadata(LLVMContext::MD_nontemporal); + bool isInvariant = I.hasMetadata(LLVMContext::MD_invariant_load); + bool isDereferenceable = + isDereferenceablePointer(SV, I.getType(), DAG.getDataLayout()); + unsigned Alignment = I.getAlignment(); + + AAMDNodes AAInfo; + I.getAAMetadata(AAInfo); + const MDNode *Ranges = I.getMetadata(LLVMContext::MD_range); + + SmallVector<EVT, 4> ValueVTs, MemVTs; + SmallVector<uint64_t, 4> Offsets; + ComputeValueVTs(TLI, DAG.getDataLayout(), Ty, ValueVTs, &MemVTs, &Offsets); + unsigned NumValues = ValueVTs.size(); + if (NumValues == 0) + return; + + SDValue Root; + bool ConstantMemory = false; + if (isVolatile) + // Serialize volatile loads with other side effects. + Root = getRoot(); + else if (NumValues > MaxParallelChains) + Root = getMemoryRoot(); + else if (AA && + AA->pointsToConstantMemory(MemoryLocation( + SV, + LocationSize::precise(DAG.getDataLayout().getTypeStoreSize(Ty)), + AAInfo))) { + // Do not serialize (non-volatile) loads of constant memory with anything. + Root = DAG.getEntryNode(); + ConstantMemory = true; + } else { + // Do not serialize non-volatile loads against each other. + Root = DAG.getRoot(); + } + + SDLoc dl = getCurSDLoc(); + + if (isVolatile) + Root = TLI.prepareVolatileOrAtomicLoad(Root, dl, DAG); + + // An aggregate load cannot wrap around the address space, so offsets to its + // parts don't wrap either. + SDNodeFlags Flags; + Flags.setNoUnsignedWrap(true); + + SmallVector<SDValue, 4> Values(NumValues); + SmallVector<SDValue, 4> Chains(std::min(MaxParallelChains, NumValues)); + EVT PtrVT = Ptr.getValueType(); + unsigned ChainI = 0; + for (unsigned i = 0; i != NumValues; ++i, ++ChainI) { + // Serializing loads here may result in excessive register pressure, and + // TokenFactor places arbitrary choke points on the scheduler. SD scheduling + // could recover a bit by hoisting nodes upward in the chain by recognizing + // they are side-effect free or do not alias. The optimizer should really + // avoid this case by converting large object/array copies to llvm.memcpy + // (MaxParallelChains should always remain as failsafe). + if (ChainI == MaxParallelChains) { + assert(PendingLoads.empty() && "PendingLoads must be serialized first"); + SDValue Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, + makeArrayRef(Chains.data(), ChainI)); + Root = Chain; + ChainI = 0; + } + SDValue A = DAG.getNode(ISD::ADD, dl, + PtrVT, Ptr, + DAG.getConstant(Offsets[i], dl, PtrVT), + Flags); + auto MMOFlags = MachineMemOperand::MONone; + if (isVolatile) + MMOFlags |= MachineMemOperand::MOVolatile; + if (isNonTemporal) + MMOFlags |= MachineMemOperand::MONonTemporal; + if (isInvariant) + MMOFlags |= MachineMemOperand::MOInvariant; + if (isDereferenceable) + MMOFlags |= MachineMemOperand::MODereferenceable; + MMOFlags |= TLI.getMMOFlags(I); + + SDValue L = DAG.getLoad(MemVTs[i], dl, Root, A, + MachinePointerInfo(SV, Offsets[i]), Alignment, + MMOFlags, AAInfo, Ranges); + Chains[ChainI] = L.getValue(1); + + if (MemVTs[i] != ValueVTs[i]) + L = DAG.getZExtOrTrunc(L, dl, ValueVTs[i]); + + Values[i] = L; + } + + if (!ConstantMemory) { + SDValue Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, + makeArrayRef(Chains.data(), ChainI)); + if (isVolatile) + DAG.setRoot(Chain); + else + PendingLoads.push_back(Chain); + } + + setValue(&I, DAG.getNode(ISD::MERGE_VALUES, dl, + DAG.getVTList(ValueVTs), Values)); +} + +void SelectionDAGBuilder::visitStoreToSwiftError(const StoreInst &I) { + assert(DAG.getTargetLoweringInfo().supportSwiftError() && + "call visitStoreToSwiftError when backend supports swifterror"); + + SmallVector<EVT, 4> ValueVTs; + SmallVector<uint64_t, 4> Offsets; + const Value *SrcV = I.getOperand(0); + ComputeValueVTs(DAG.getTargetLoweringInfo(), DAG.getDataLayout(), + SrcV->getType(), ValueVTs, &Offsets); + assert(ValueVTs.size() == 1 && Offsets[0] == 0 && + "expect a single EVT for swifterror"); + + SDValue Src = getValue(SrcV); + // Create a virtual register, then update the virtual register. + Register VReg = + SwiftError.getOrCreateVRegDefAt(&I, FuncInfo.MBB, I.getPointerOperand()); + // Chain, DL, Reg, N or Chain, DL, Reg, N, Glue + // Chain can be getRoot or getControlRoot. + SDValue CopyNode = DAG.getCopyToReg(getRoot(), getCurSDLoc(), VReg, + SDValue(Src.getNode(), Src.getResNo())); + DAG.setRoot(CopyNode); +} + +void SelectionDAGBuilder::visitLoadFromSwiftError(const LoadInst &I) { + assert(DAG.getTargetLoweringInfo().supportSwiftError() && + "call visitLoadFromSwiftError when backend supports swifterror"); + + assert(!I.isVolatile() && + !I.hasMetadata(LLVMContext::MD_nontemporal) && + !I.hasMetadata(LLVMContext::MD_invariant_load) && + "Support volatile, non temporal, invariant for load_from_swift_error"); + + const Value *SV = I.getOperand(0); + Type *Ty = I.getType(); + AAMDNodes AAInfo; + I.getAAMetadata(AAInfo); + assert( + (!AA || + !AA->pointsToConstantMemory(MemoryLocation( + SV, LocationSize::precise(DAG.getDataLayout().getTypeStoreSize(Ty)), + AAInfo))) && + "load_from_swift_error should not be constant memory"); + + SmallVector<EVT, 4> ValueVTs; + SmallVector<uint64_t, 4> Offsets; + ComputeValueVTs(DAG.getTargetLoweringInfo(), DAG.getDataLayout(), Ty, + ValueVTs, &Offsets); + assert(ValueVTs.size() == 1 && Offsets[0] == 0 && + "expect a single EVT for swifterror"); + + // Chain, DL, Reg, VT, Glue or Chain, DL, Reg, VT + SDValue L = DAG.getCopyFromReg( + getRoot(), getCurSDLoc(), + SwiftError.getOrCreateVRegUseAt(&I, FuncInfo.MBB, SV), ValueVTs[0]); + + setValue(&I, L); +} + +void SelectionDAGBuilder::visitStore(const StoreInst &I) { + if (I.isAtomic()) + return visitAtomicStore(I); + + const Value *SrcV = I.getOperand(0); + const Value *PtrV = I.getOperand(1); + + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + if (TLI.supportSwiftError()) { + // Swifterror values can come from either a function parameter with + // swifterror attribute or an alloca with swifterror attribute. + if (const Argument *Arg = dyn_cast<Argument>(PtrV)) { + if (Arg->hasSwiftErrorAttr()) + return visitStoreToSwiftError(I); + } + + if (const AllocaInst *Alloca = dyn_cast<AllocaInst>(PtrV)) { + if (Alloca->isSwiftError()) + return visitStoreToSwiftError(I); + } + } + + SmallVector<EVT, 4> ValueVTs, MemVTs; + SmallVector<uint64_t, 4> Offsets; + ComputeValueVTs(DAG.getTargetLoweringInfo(), DAG.getDataLayout(), + SrcV->getType(), ValueVTs, &MemVTs, &Offsets); + unsigned NumValues = ValueVTs.size(); + if (NumValues == 0) + return; + + // Get the lowered operands. Note that we do this after + // checking if NumResults is zero, because with zero results + // the operands won't have values in the map. + SDValue Src = getValue(SrcV); + SDValue Ptr = getValue(PtrV); + + SDValue Root = I.isVolatile() ? getRoot() : getMemoryRoot(); + SmallVector<SDValue, 4> Chains(std::min(MaxParallelChains, NumValues)); + SDLoc dl = getCurSDLoc(); + unsigned Alignment = I.getAlignment(); + AAMDNodes AAInfo; + I.getAAMetadata(AAInfo); + + auto MMOFlags = MachineMemOperand::MONone; + if (I.isVolatile()) + MMOFlags |= MachineMemOperand::MOVolatile; + if (I.hasMetadata(LLVMContext::MD_nontemporal)) + MMOFlags |= MachineMemOperand::MONonTemporal; + MMOFlags |= TLI.getMMOFlags(I); + + // An aggregate load cannot wrap around the address space, so offsets to its + // parts don't wrap either. + SDNodeFlags Flags; + Flags.setNoUnsignedWrap(true); + + unsigned ChainI = 0; + for (unsigned i = 0; i != NumValues; ++i, ++ChainI) { + // See visitLoad comments. + if (ChainI == MaxParallelChains) { + SDValue Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, + makeArrayRef(Chains.data(), ChainI)); + Root = Chain; + ChainI = 0; + } + SDValue Add = DAG.getMemBasePlusOffset(Ptr, Offsets[i], dl, Flags); + SDValue Val = SDValue(Src.getNode(), Src.getResNo() + i); + if (MemVTs[i] != ValueVTs[i]) + Val = DAG.getPtrExtOrTrunc(Val, dl, MemVTs[i]); + SDValue St = + DAG.getStore(Root, dl, Val, Add, MachinePointerInfo(PtrV, Offsets[i]), + Alignment, MMOFlags, AAInfo); + Chains[ChainI] = St; + } + + SDValue StoreNode = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, + makeArrayRef(Chains.data(), ChainI)); + DAG.setRoot(StoreNode); +} + +void SelectionDAGBuilder::visitMaskedStore(const CallInst &I, + bool IsCompressing) { + SDLoc sdl = getCurSDLoc(); + + auto getMaskedStoreOps = [&](Value* &Ptr, Value* &Mask, Value* &Src0, + unsigned& Alignment) { + // llvm.masked.store.*(Src0, Ptr, alignment, Mask) + Src0 = I.getArgOperand(0); + Ptr = I.getArgOperand(1); + Alignment = cast<ConstantInt>(I.getArgOperand(2))->getZExtValue(); + Mask = I.getArgOperand(3); + }; + auto getCompressingStoreOps = [&](Value* &Ptr, Value* &Mask, Value* &Src0, + unsigned& Alignment) { + // llvm.masked.compressstore.*(Src0, Ptr, Mask) + Src0 = I.getArgOperand(0); + Ptr = I.getArgOperand(1); + Mask = I.getArgOperand(2); + Alignment = 0; + }; + + Value *PtrOperand, *MaskOperand, *Src0Operand; + unsigned Alignment; + if (IsCompressing) + getCompressingStoreOps(PtrOperand, MaskOperand, Src0Operand, Alignment); + else + getMaskedStoreOps(PtrOperand, MaskOperand, Src0Operand, Alignment); + + SDValue Ptr = getValue(PtrOperand); + SDValue Src0 = getValue(Src0Operand); + SDValue Mask = getValue(MaskOperand); + SDValue Offset = DAG.getUNDEF(Ptr.getValueType()); + + EVT VT = Src0.getValueType(); + if (!Alignment) + Alignment = DAG.getEVTAlignment(VT); + + AAMDNodes AAInfo; + I.getAAMetadata(AAInfo); + + MachineMemOperand *MMO = + DAG.getMachineFunction(). + getMachineMemOperand(MachinePointerInfo(PtrOperand), + MachineMemOperand::MOStore, + // TODO: Make MachineMemOperands aware of scalable + // vectors. + VT.getStoreSize().getKnownMinSize(), + Alignment, AAInfo); + SDValue StoreNode = + DAG.getMaskedStore(getMemoryRoot(), sdl, Src0, Ptr, Offset, Mask, VT, MMO, + ISD::UNINDEXED, false /* Truncating */, IsCompressing); + DAG.setRoot(StoreNode); + setValue(&I, StoreNode); +} + +// Get a uniform base for the Gather/Scatter intrinsic. +// The first argument of the Gather/Scatter intrinsic is a vector of pointers. +// We try to represent it as a base pointer + vector of indices. +// Usually, the vector of pointers comes from a 'getelementptr' instruction. +// The first operand of the GEP may be a single pointer or a vector of pointers +// Example: +// %gep.ptr = getelementptr i32, <8 x i32*> %vptr, <8 x i32> %ind +// or +// %gep.ptr = getelementptr i32, i32* %ptr, <8 x i32> %ind +// %res = call <8 x i32> @llvm.masked.gather.v8i32(<8 x i32*> %gep.ptr, .. +// +// When the first GEP operand is a single pointer - it is the uniform base we +// are looking for. If first operand of the GEP is a splat vector - we +// extract the splat value and use it as a uniform base. +// In all other cases the function returns 'false'. +static bool getUniformBase(const Value *&Ptr, SDValue &Base, SDValue &Index, + ISD::MemIndexType &IndexType, SDValue &Scale, + SelectionDAGBuilder *SDB) { + SelectionDAG& DAG = SDB->DAG; + LLVMContext &Context = *DAG.getContext(); + + assert(Ptr->getType()->isVectorTy() && "Uexpected pointer type"); + const GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Ptr); + if (!GEP) + return false; + + const Value *GEPPtr = GEP->getPointerOperand(); + if (!GEPPtr->getType()->isVectorTy()) + Ptr = GEPPtr; + else if (!(Ptr = getSplatValue(GEPPtr))) + return false; + + unsigned FinalIndex = GEP->getNumOperands() - 1; + Value *IndexVal = GEP->getOperand(FinalIndex); + gep_type_iterator GTI = gep_type_begin(*GEP); + + // Ensure all the other indices are 0. + for (unsigned i = 1; i < FinalIndex; ++i, ++GTI) { + auto *C = dyn_cast<Constant>(GEP->getOperand(i)); + if (!C) + return false; + if (isa<VectorType>(C->getType())) + C = C->getSplatValue(); + auto *CI = dyn_cast_or_null<ConstantInt>(C); + if (!CI || !CI->isZero()) + return false; + } + + // The operands of the GEP may be defined in another basic block. + // In this case we'll not find nodes for the operands. + if (!SDB->findValue(Ptr)) + return false; + Constant *C = dyn_cast<Constant>(IndexVal); + if (!C && !SDB->findValue(IndexVal)) + return false; + + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + const DataLayout &DL = DAG.getDataLayout(); + StructType *STy = GTI.getStructTypeOrNull(); + + if (STy) { + const StructLayout *SL = DL.getStructLayout(STy); + if (isa<VectorType>(C->getType())) { + C = C->getSplatValue(); + // FIXME: If getSplatValue may return nullptr for a structure? + // If not, the following check can be removed. + if (!C) + return false; + } + auto *CI = cast<ConstantInt>(C); + Scale = DAG.getTargetConstant(1, SDB->getCurSDLoc(), TLI.getPointerTy(DL)); + Index = DAG.getConstant(SL->getElementOffset(CI->getZExtValue()), + SDB->getCurSDLoc(), TLI.getPointerTy(DL)); + } else { + Scale = DAG.getTargetConstant( + DL.getTypeAllocSize(GEP->getResultElementType()), + SDB->getCurSDLoc(), TLI.getPointerTy(DL)); + Index = SDB->getValue(IndexVal); + } + Base = SDB->getValue(Ptr); + IndexType = ISD::SIGNED_SCALED; + + if (STy || !Index.getValueType().isVector()) { + unsigned GEPWidth = GEP->getType()->getVectorNumElements(); + EVT VT = EVT::getVectorVT(Context, Index.getValueType(), GEPWidth); + Index = DAG.getSplatBuildVector(VT, SDLoc(Index), Index); + } + return true; +} + +void SelectionDAGBuilder::visitMaskedScatter(const CallInst &I) { + SDLoc sdl = getCurSDLoc(); + + // llvm.masked.scatter.*(Src0, Ptrs, alignment, Mask) + const Value *Ptr = I.getArgOperand(1); + SDValue Src0 = getValue(I.getArgOperand(0)); + SDValue Mask = getValue(I.getArgOperand(3)); + EVT VT = Src0.getValueType(); + unsigned Alignment = (cast<ConstantInt>(I.getArgOperand(2)))->getZExtValue(); + if (!Alignment) + Alignment = DAG.getEVTAlignment(VT); + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + + AAMDNodes AAInfo; + I.getAAMetadata(AAInfo); + + SDValue Base; + SDValue Index; + ISD::MemIndexType IndexType; + SDValue Scale; + const Value *BasePtr = Ptr; + bool UniformBase = getUniformBase(BasePtr, Base, Index, IndexType, Scale, + this); + + const Value *MemOpBasePtr = UniformBase ? BasePtr : nullptr; + MachineMemOperand *MMO = DAG.getMachineFunction(). + getMachineMemOperand(MachinePointerInfo(MemOpBasePtr), + MachineMemOperand::MOStore, + // TODO: Make MachineMemOperands aware of scalable + // vectors. + VT.getStoreSize().getKnownMinSize(), + Alignment, AAInfo); + if (!UniformBase) { + Base = DAG.getConstant(0, sdl, TLI.getPointerTy(DAG.getDataLayout())); + Index = getValue(Ptr); + IndexType = ISD::SIGNED_SCALED; + Scale = DAG.getTargetConstant(1, sdl, TLI.getPointerTy(DAG.getDataLayout())); + } + SDValue Ops[] = { getMemoryRoot(), Src0, Mask, Base, Index, Scale }; + SDValue Scatter = DAG.getMaskedScatter(DAG.getVTList(MVT::Other), VT, sdl, + Ops, MMO, IndexType); + DAG.setRoot(Scatter); + setValue(&I, Scatter); +} + +void SelectionDAGBuilder::visitMaskedLoad(const CallInst &I, bool IsExpanding) { + SDLoc sdl = getCurSDLoc(); + + auto getMaskedLoadOps = [&](Value* &Ptr, Value* &Mask, Value* &Src0, + unsigned& Alignment) { + // @llvm.masked.load.*(Ptr, alignment, Mask, Src0) + Ptr = I.getArgOperand(0); + Alignment = cast<ConstantInt>(I.getArgOperand(1))->getZExtValue(); + Mask = I.getArgOperand(2); + Src0 = I.getArgOperand(3); + }; + auto getExpandingLoadOps = [&](Value* &Ptr, Value* &Mask, Value* &Src0, + unsigned& Alignment) { + // @llvm.masked.expandload.*(Ptr, Mask, Src0) + Ptr = I.getArgOperand(0); + Alignment = 0; + Mask = I.getArgOperand(1); + Src0 = I.getArgOperand(2); + }; + + Value *PtrOperand, *MaskOperand, *Src0Operand; + unsigned Alignment; + if (IsExpanding) + getExpandingLoadOps(PtrOperand, MaskOperand, Src0Operand, Alignment); + else + getMaskedLoadOps(PtrOperand, MaskOperand, Src0Operand, Alignment); + + SDValue Ptr = getValue(PtrOperand); + SDValue Src0 = getValue(Src0Operand); + SDValue Mask = getValue(MaskOperand); + SDValue Offset = DAG.getUNDEF(Ptr.getValueType()); + + EVT VT = Src0.getValueType(); + if (!Alignment) + Alignment = DAG.getEVTAlignment(VT); + + AAMDNodes AAInfo; + I.getAAMetadata(AAInfo); + const MDNode *Ranges = I.getMetadata(LLVMContext::MD_range); + + // Do not serialize masked loads of constant memory with anything. + MemoryLocation ML; + if (VT.isScalableVector()) + ML = MemoryLocation(PtrOperand); + else + ML = MemoryLocation(PtrOperand, LocationSize::precise( + DAG.getDataLayout().getTypeStoreSize(I.getType())), + AAInfo); + bool AddToChain = !AA || !AA->pointsToConstantMemory(ML); + + SDValue InChain = AddToChain ? DAG.getRoot() : DAG.getEntryNode(); + + MachineMemOperand *MMO = + DAG.getMachineFunction(). + getMachineMemOperand(MachinePointerInfo(PtrOperand), + MachineMemOperand::MOLoad, + // TODO: Make MachineMemOperands aware of scalable + // vectors. + VT.getStoreSize().getKnownMinSize(), + Alignment, AAInfo, Ranges); + + SDValue Load = + DAG.getMaskedLoad(VT, sdl, InChain, Ptr, Offset, Mask, Src0, VT, MMO, + ISD::UNINDEXED, ISD::NON_EXTLOAD, IsExpanding); + if (AddToChain) + PendingLoads.push_back(Load.getValue(1)); + setValue(&I, Load); +} + +void SelectionDAGBuilder::visitMaskedGather(const CallInst &I) { + SDLoc sdl = getCurSDLoc(); + + // @llvm.masked.gather.*(Ptrs, alignment, Mask, Src0) + const Value *Ptr = I.getArgOperand(0); + SDValue Src0 = getValue(I.getArgOperand(3)); + SDValue Mask = getValue(I.getArgOperand(2)); + + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + EVT VT = TLI.getValueType(DAG.getDataLayout(), I.getType()); + unsigned Alignment = (cast<ConstantInt>(I.getArgOperand(1)))->getZExtValue(); + if (!Alignment) + Alignment = DAG.getEVTAlignment(VT); + + AAMDNodes AAInfo; + I.getAAMetadata(AAInfo); + const MDNode *Ranges = I.getMetadata(LLVMContext::MD_range); + + SDValue Root = DAG.getRoot(); + SDValue Base; + SDValue Index; + ISD::MemIndexType IndexType; + SDValue Scale; + const Value *BasePtr = Ptr; + bool UniformBase = getUniformBase(BasePtr, Base, Index, IndexType, Scale, + this); + bool ConstantMemory = false; + if (UniformBase && AA && + AA->pointsToConstantMemory( + MemoryLocation(BasePtr, + LocationSize::precise( + DAG.getDataLayout().getTypeStoreSize(I.getType())), + AAInfo))) { + // Do not serialize (non-volatile) loads of constant memory with anything. + Root = DAG.getEntryNode(); + ConstantMemory = true; + } + + MachineMemOperand *MMO = + DAG.getMachineFunction(). + getMachineMemOperand(MachinePointerInfo(UniformBase ? BasePtr : nullptr), + MachineMemOperand::MOLoad, + // TODO: Make MachineMemOperands aware of scalable + // vectors. + VT.getStoreSize().getKnownMinSize(), + Alignment, AAInfo, Ranges); + + if (!UniformBase) { + Base = DAG.getConstant(0, sdl, TLI.getPointerTy(DAG.getDataLayout())); + Index = getValue(Ptr); + IndexType = ISD::SIGNED_SCALED; + Scale = DAG.getTargetConstant(1, sdl, TLI.getPointerTy(DAG.getDataLayout())); + } + SDValue Ops[] = { Root, Src0, Mask, Base, Index, Scale }; + SDValue Gather = DAG.getMaskedGather(DAG.getVTList(VT, MVT::Other), VT, sdl, + Ops, MMO, IndexType); + + SDValue OutChain = Gather.getValue(1); + if (!ConstantMemory) + PendingLoads.push_back(OutChain); + setValue(&I, Gather); +} + +void SelectionDAGBuilder::visitAtomicCmpXchg(const AtomicCmpXchgInst &I) { + SDLoc dl = getCurSDLoc(); + AtomicOrdering SuccessOrdering = I.getSuccessOrdering(); + AtomicOrdering FailureOrdering = I.getFailureOrdering(); + SyncScope::ID SSID = I.getSyncScopeID(); + + SDValue InChain = getRoot(); + + MVT MemVT = getValue(I.getCompareOperand()).getSimpleValueType(); + SDVTList VTs = DAG.getVTList(MemVT, MVT::i1, MVT::Other); + + auto Alignment = DAG.getEVTAlignment(MemVT); + + auto Flags = MachineMemOperand::MOLoad | MachineMemOperand::MOStore; + if (I.isVolatile()) + Flags |= MachineMemOperand::MOVolatile; + Flags |= DAG.getTargetLoweringInfo().getMMOFlags(I); + + MachineFunction &MF = DAG.getMachineFunction(); + MachineMemOperand *MMO = + MF.getMachineMemOperand(MachinePointerInfo(I.getPointerOperand()), + Flags, MemVT.getStoreSize(), Alignment, + AAMDNodes(), nullptr, SSID, SuccessOrdering, + FailureOrdering); + + SDValue L = DAG.getAtomicCmpSwap(ISD::ATOMIC_CMP_SWAP_WITH_SUCCESS, + dl, MemVT, VTs, InChain, + getValue(I.getPointerOperand()), + getValue(I.getCompareOperand()), + getValue(I.getNewValOperand()), MMO); + + SDValue OutChain = L.getValue(2); + + setValue(&I, L); + DAG.setRoot(OutChain); +} + +void SelectionDAGBuilder::visitAtomicRMW(const AtomicRMWInst &I) { + SDLoc dl = getCurSDLoc(); + ISD::NodeType NT; + switch (I.getOperation()) { + default: llvm_unreachable("Unknown atomicrmw operation"); + case AtomicRMWInst::Xchg: NT = ISD::ATOMIC_SWAP; break; + case AtomicRMWInst::Add: NT = ISD::ATOMIC_LOAD_ADD; break; + case AtomicRMWInst::Sub: NT = ISD::ATOMIC_LOAD_SUB; break; + case AtomicRMWInst::And: NT = ISD::ATOMIC_LOAD_AND; break; + case AtomicRMWInst::Nand: NT = ISD::ATOMIC_LOAD_NAND; break; + case AtomicRMWInst::Or: NT = ISD::ATOMIC_LOAD_OR; break; + case AtomicRMWInst::Xor: NT = ISD::ATOMIC_LOAD_XOR; break; + case AtomicRMWInst::Max: NT = ISD::ATOMIC_LOAD_MAX; break; + case AtomicRMWInst::Min: NT = ISD::ATOMIC_LOAD_MIN; break; + case AtomicRMWInst::UMax: NT = ISD::ATOMIC_LOAD_UMAX; break; + case AtomicRMWInst::UMin: NT = ISD::ATOMIC_LOAD_UMIN; break; + case AtomicRMWInst::FAdd: NT = ISD::ATOMIC_LOAD_FADD; break; + case AtomicRMWInst::FSub: NT = ISD::ATOMIC_LOAD_FSUB; break; + } + AtomicOrdering Ordering = I.getOrdering(); + SyncScope::ID SSID = I.getSyncScopeID(); + + SDValue InChain = getRoot(); + + auto MemVT = getValue(I.getValOperand()).getSimpleValueType(); + auto Alignment = DAG.getEVTAlignment(MemVT); + + auto Flags = MachineMemOperand::MOLoad | MachineMemOperand::MOStore; + if (I.isVolatile()) + Flags |= MachineMemOperand::MOVolatile; + Flags |= DAG.getTargetLoweringInfo().getMMOFlags(I); + + MachineFunction &MF = DAG.getMachineFunction(); + MachineMemOperand *MMO = + MF.getMachineMemOperand(MachinePointerInfo(I.getPointerOperand()), Flags, + MemVT.getStoreSize(), Alignment, AAMDNodes(), + nullptr, SSID, Ordering); + + SDValue L = + DAG.getAtomic(NT, dl, MemVT, InChain, + getValue(I.getPointerOperand()), getValue(I.getValOperand()), + MMO); + + SDValue OutChain = L.getValue(1); + + setValue(&I, L); + DAG.setRoot(OutChain); +} + +void SelectionDAGBuilder::visitFence(const FenceInst &I) { + SDLoc dl = getCurSDLoc(); + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + SDValue Ops[3]; + Ops[0] = getRoot(); + Ops[1] = DAG.getTargetConstant((unsigned)I.getOrdering(), dl, + TLI.getFenceOperandTy(DAG.getDataLayout())); + Ops[2] = DAG.getTargetConstant(I.getSyncScopeID(), dl, + TLI.getFenceOperandTy(DAG.getDataLayout())); + DAG.setRoot(DAG.getNode(ISD::ATOMIC_FENCE, dl, MVT::Other, Ops)); +} + +void SelectionDAGBuilder::visitAtomicLoad(const LoadInst &I) { + SDLoc dl = getCurSDLoc(); + AtomicOrdering Order = I.getOrdering(); + SyncScope::ID SSID = I.getSyncScopeID(); + + SDValue InChain = getRoot(); + + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + EVT VT = TLI.getValueType(DAG.getDataLayout(), I.getType()); + EVT MemVT = TLI.getMemValueType(DAG.getDataLayout(), I.getType()); + + if (!TLI.supportsUnalignedAtomics() && + I.getAlignment() < MemVT.getSizeInBits() / 8) + report_fatal_error("Cannot generate unaligned atomic load"); + + auto Flags = MachineMemOperand::MOLoad; + if (I.isVolatile()) + Flags |= MachineMemOperand::MOVolatile; + if (I.hasMetadata(LLVMContext::MD_invariant_load)) + Flags |= MachineMemOperand::MOInvariant; + if (isDereferenceablePointer(I.getPointerOperand(), I.getType(), + DAG.getDataLayout())) + Flags |= MachineMemOperand::MODereferenceable; + + Flags |= TLI.getMMOFlags(I); + + MachineMemOperand *MMO = + DAG.getMachineFunction(). + getMachineMemOperand(MachinePointerInfo(I.getPointerOperand()), + Flags, MemVT.getStoreSize(), + I.getAlignment() ? I.getAlignment() : + DAG.getEVTAlignment(MemVT), + AAMDNodes(), nullptr, SSID, Order); + + InChain = TLI.prepareVolatileOrAtomicLoad(InChain, dl, DAG); + + SDValue Ptr = getValue(I.getPointerOperand()); + + if (TLI.lowerAtomicLoadAsLoadSDNode(I)) { + // TODO: Once this is better exercised by tests, it should be merged with + // the normal path for loads to prevent future divergence. + SDValue L = DAG.getLoad(MemVT, dl, InChain, Ptr, MMO); + if (MemVT != VT) + L = DAG.getPtrExtOrTrunc(L, dl, VT); + + setValue(&I, L); + SDValue OutChain = L.getValue(1); + if (!I.isUnordered()) + DAG.setRoot(OutChain); + else + PendingLoads.push_back(OutChain); + return; + } + + SDValue L = DAG.getAtomic(ISD::ATOMIC_LOAD, dl, MemVT, MemVT, InChain, + Ptr, MMO); + + SDValue OutChain = L.getValue(1); + if (MemVT != VT) + L = DAG.getPtrExtOrTrunc(L, dl, VT); + + setValue(&I, L); + DAG.setRoot(OutChain); +} + +void SelectionDAGBuilder::visitAtomicStore(const StoreInst &I) { + SDLoc dl = getCurSDLoc(); + + AtomicOrdering Ordering = I.getOrdering(); + SyncScope::ID SSID = I.getSyncScopeID(); + + SDValue InChain = getRoot(); + + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + EVT MemVT = + TLI.getMemValueType(DAG.getDataLayout(), I.getValueOperand()->getType()); + + if (I.getAlignment() < MemVT.getSizeInBits() / 8) + report_fatal_error("Cannot generate unaligned atomic store"); + + auto Flags = MachineMemOperand::MOStore; + if (I.isVolatile()) + Flags |= MachineMemOperand::MOVolatile; + Flags |= TLI.getMMOFlags(I); + + MachineFunction &MF = DAG.getMachineFunction(); + MachineMemOperand *MMO = + MF.getMachineMemOperand(MachinePointerInfo(I.getPointerOperand()), Flags, + MemVT.getStoreSize(), I.getAlignment(), AAMDNodes(), + nullptr, SSID, Ordering); + + SDValue Val = getValue(I.getValueOperand()); + if (Val.getValueType() != MemVT) + Val = DAG.getPtrExtOrTrunc(Val, dl, MemVT); + SDValue Ptr = getValue(I.getPointerOperand()); + + if (TLI.lowerAtomicStoreAsStoreSDNode(I)) { + // TODO: Once this is better exercised by tests, it should be merged with + // the normal path for stores to prevent future divergence. + SDValue S = DAG.getStore(InChain, dl, Val, Ptr, MMO); + DAG.setRoot(S); + return; + } + SDValue OutChain = DAG.getAtomic(ISD::ATOMIC_STORE, dl, MemVT, InChain, + Ptr, Val, MMO); + + + DAG.setRoot(OutChain); +} + +/// visitTargetIntrinsic - Lower a call of a target intrinsic to an INTRINSIC +/// node. +void SelectionDAGBuilder::visitTargetIntrinsic(const CallInst &I, + unsigned Intrinsic) { + // Ignore the callsite's attributes. A specific call site may be marked with + // readnone, but the lowering code will expect the chain based on the + // definition. + const Function *F = I.getCalledFunction(); + bool HasChain = !F->doesNotAccessMemory(); + bool OnlyLoad = HasChain && F->onlyReadsMemory(); + + // Build the operand list. + SmallVector<SDValue, 8> Ops; + if (HasChain) { // If this intrinsic has side-effects, chainify it. + if (OnlyLoad) { + // We don't need to serialize loads against other loads. + Ops.push_back(DAG.getRoot()); + } else { + Ops.push_back(getRoot()); + } + } + + // Info is set by getTgtMemInstrinsic + TargetLowering::IntrinsicInfo Info; + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + bool IsTgtIntrinsic = TLI.getTgtMemIntrinsic(Info, I, + DAG.getMachineFunction(), + Intrinsic); + + // Add the intrinsic ID as an integer operand if it's not a target intrinsic. + if (!IsTgtIntrinsic || Info.opc == ISD::INTRINSIC_VOID || + Info.opc == ISD::INTRINSIC_W_CHAIN) + Ops.push_back(DAG.getTargetConstant(Intrinsic, getCurSDLoc(), + TLI.getPointerTy(DAG.getDataLayout()))); + + // Add all operands of the call to the operand list. + for (unsigned i = 0, e = I.getNumArgOperands(); i != e; ++i) { + const Value *Arg = I.getArgOperand(i); + if (!I.paramHasAttr(i, Attribute::ImmArg)) { + Ops.push_back(getValue(Arg)); + continue; + } + + // Use TargetConstant instead of a regular constant for immarg. + EVT VT = TLI.getValueType(*DL, Arg->getType(), true); + if (const ConstantInt *CI = dyn_cast<ConstantInt>(Arg)) { + assert(CI->getBitWidth() <= 64 && + "large intrinsic immediates not handled"); + Ops.push_back(DAG.getTargetConstant(*CI, SDLoc(), VT)); + } else { + Ops.push_back( + DAG.getTargetConstantFP(*cast<ConstantFP>(Arg), SDLoc(), VT)); + } + } + + SmallVector<EVT, 4> ValueVTs; + ComputeValueVTs(TLI, DAG.getDataLayout(), I.getType(), ValueVTs); + + if (HasChain) + ValueVTs.push_back(MVT::Other); + + SDVTList VTs = DAG.getVTList(ValueVTs); + + // Create the node. + SDValue Result; + if (IsTgtIntrinsic) { + // This is target intrinsic that touches memory + AAMDNodes AAInfo; + I.getAAMetadata(AAInfo); + Result = DAG.getMemIntrinsicNode( + Info.opc, getCurSDLoc(), VTs, Ops, Info.memVT, + MachinePointerInfo(Info.ptrVal, Info.offset), + Info.align ? Info.align->value() : 0, Info.flags, Info.size, AAInfo); + } else if (!HasChain) { + Result = DAG.getNode(ISD::INTRINSIC_WO_CHAIN, getCurSDLoc(), VTs, Ops); + } else if (!I.getType()->isVoidTy()) { + Result = DAG.getNode(ISD::INTRINSIC_W_CHAIN, getCurSDLoc(), VTs, Ops); + } else { + Result = DAG.getNode(ISD::INTRINSIC_VOID, getCurSDLoc(), VTs, Ops); + } + + if (HasChain) { + SDValue Chain = Result.getValue(Result.getNode()->getNumValues()-1); + if (OnlyLoad) + PendingLoads.push_back(Chain); + else + DAG.setRoot(Chain); + } + + if (!I.getType()->isVoidTy()) { + if (VectorType *PTy = dyn_cast<VectorType>(I.getType())) { + EVT VT = TLI.getValueType(DAG.getDataLayout(), PTy); + Result = DAG.getNode(ISD::BITCAST, getCurSDLoc(), VT, Result); + } else + Result = lowerRangeToAssertZExt(DAG, I, Result); + + setValue(&I, Result); + } +} + +/// GetSignificand - Get the significand and build it into a floating-point +/// number with exponent of 1: +/// +/// Op = (Op & 0x007fffff) | 0x3f800000; +/// +/// where Op is the hexadecimal representation of floating point value. +static SDValue GetSignificand(SelectionDAG &DAG, SDValue Op, const SDLoc &dl) { + SDValue t1 = DAG.getNode(ISD::AND, dl, MVT::i32, Op, + DAG.getConstant(0x007fffff, dl, MVT::i32)); + SDValue t2 = DAG.getNode(ISD::OR, dl, MVT::i32, t1, + DAG.getConstant(0x3f800000, dl, MVT::i32)); + return DAG.getNode(ISD::BITCAST, dl, MVT::f32, t2); +} + +/// GetExponent - Get the exponent: +/// +/// (float)(int)(((Op & 0x7f800000) >> 23) - 127); +/// +/// where Op is the hexadecimal representation of floating point value. +static SDValue GetExponent(SelectionDAG &DAG, SDValue Op, + const TargetLowering &TLI, const SDLoc &dl) { + SDValue t0 = DAG.getNode(ISD::AND, dl, MVT::i32, Op, + DAG.getConstant(0x7f800000, dl, MVT::i32)); + SDValue t1 = DAG.getNode( + ISD::SRL, dl, MVT::i32, t0, + DAG.getConstant(23, dl, TLI.getPointerTy(DAG.getDataLayout()))); + SDValue t2 = DAG.getNode(ISD::SUB, dl, MVT::i32, t1, + DAG.getConstant(127, dl, MVT::i32)); + return DAG.getNode(ISD::SINT_TO_FP, dl, MVT::f32, t2); +} + +/// getF32Constant - Get 32-bit floating point constant. +static SDValue getF32Constant(SelectionDAG &DAG, unsigned Flt, + const SDLoc &dl) { + return DAG.getConstantFP(APFloat(APFloat::IEEEsingle(), APInt(32, Flt)), dl, + MVT::f32); +} + +static SDValue getLimitedPrecisionExp2(SDValue t0, const SDLoc &dl, + SelectionDAG &DAG) { + // TODO: What fast-math-flags should be set on the floating-point nodes? + + // IntegerPartOfX = ((int32_t)(t0); + SDValue IntegerPartOfX = DAG.getNode(ISD::FP_TO_SINT, dl, MVT::i32, t0); + + // FractionalPartOfX = t0 - (float)IntegerPartOfX; + SDValue t1 = DAG.getNode(ISD::SINT_TO_FP, dl, MVT::f32, IntegerPartOfX); + SDValue X = DAG.getNode(ISD::FSUB, dl, MVT::f32, t0, t1); + + // IntegerPartOfX <<= 23; + IntegerPartOfX = DAG.getNode( + ISD::SHL, dl, MVT::i32, IntegerPartOfX, + DAG.getConstant(23, dl, DAG.getTargetLoweringInfo().getPointerTy( + DAG.getDataLayout()))); + + SDValue TwoToFractionalPartOfX; + if (LimitFloatPrecision <= 6) { + // For floating-point precision of 6: + // + // TwoToFractionalPartOfX = + // 0.997535578f + + // (0.735607626f + 0.252464424f * x) * x; + // + // error 0.0144103317, which is 6 bits + SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X, + getF32Constant(DAG, 0x3e814304, dl)); + SDValue t3 = DAG.getNode(ISD::FADD, dl, MVT::f32, t2, + getF32Constant(DAG, 0x3f3c50c8, dl)); + SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X); + TwoToFractionalPartOfX = DAG.getNode(ISD::FADD, dl, MVT::f32, t4, + getF32Constant(DAG, 0x3f7f5e7e, dl)); + } else if (LimitFloatPrecision <= 12) { + // For floating-point precision of 12: + // + // TwoToFractionalPartOfX = + // 0.999892986f + + // (0.696457318f + + // (0.224338339f + 0.792043434e-1f * x) * x) * x; + // + // error 0.000107046256, which is 13 to 14 bits + SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X, + getF32Constant(DAG, 0x3da235e3, dl)); + SDValue t3 = DAG.getNode(ISD::FADD, dl, MVT::f32, t2, + getF32Constant(DAG, 0x3e65b8f3, dl)); + SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X); + SDValue t5 = DAG.getNode(ISD::FADD, dl, MVT::f32, t4, + getF32Constant(DAG, 0x3f324b07, dl)); + SDValue t6 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t5, X); + TwoToFractionalPartOfX = DAG.getNode(ISD::FADD, dl, MVT::f32, t6, + getF32Constant(DAG, 0x3f7ff8fd, dl)); + } else { // LimitFloatPrecision <= 18 + // For floating-point precision of 18: + // + // TwoToFractionalPartOfX = + // 0.999999982f + + // (0.693148872f + + // (0.240227044f + + // (0.554906021e-1f + + // (0.961591928e-2f + + // (0.136028312e-2f + 0.157059148e-3f *x)*x)*x)*x)*x)*x; + // error 2.47208000*10^(-7), which is better than 18 bits + SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X, + getF32Constant(DAG, 0x3924b03e, dl)); + SDValue t3 = DAG.getNode(ISD::FADD, dl, MVT::f32, t2, + getF32Constant(DAG, 0x3ab24b87, dl)); + SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X); + SDValue t5 = DAG.getNode(ISD::FADD, dl, MVT::f32, t4, + getF32Constant(DAG, 0x3c1d8c17, dl)); + SDValue t6 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t5, X); + SDValue t7 = DAG.getNode(ISD::FADD, dl, MVT::f32, t6, + getF32Constant(DAG, 0x3d634a1d, dl)); + SDValue t8 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t7, X); + SDValue t9 = DAG.getNode(ISD::FADD, dl, MVT::f32, t8, + getF32Constant(DAG, 0x3e75fe14, dl)); + SDValue t10 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t9, X); + SDValue t11 = DAG.getNode(ISD::FADD, dl, MVT::f32, t10, + getF32Constant(DAG, 0x3f317234, dl)); + SDValue t12 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t11, X); + TwoToFractionalPartOfX = DAG.getNode(ISD::FADD, dl, MVT::f32, t12, + getF32Constant(DAG, 0x3f800000, dl)); + } + + // Add the exponent into the result in integer domain. + SDValue t13 = DAG.getNode(ISD::BITCAST, dl, MVT::i32, TwoToFractionalPartOfX); + return DAG.getNode(ISD::BITCAST, dl, MVT::f32, + DAG.getNode(ISD::ADD, dl, MVT::i32, t13, IntegerPartOfX)); +} + +/// expandExp - Lower an exp intrinsic. Handles the special sequences for +/// limited-precision mode. +static SDValue expandExp(const SDLoc &dl, SDValue Op, SelectionDAG &DAG, + const TargetLowering &TLI) { + if (Op.getValueType() == MVT::f32 && + LimitFloatPrecision > 0 && LimitFloatPrecision <= 18) { + + // Put the exponent in the right bit position for later addition to the + // final result: + // + // t0 = Op * log2(e) + + // TODO: What fast-math-flags should be set here? + SDValue t0 = DAG.getNode(ISD::FMUL, dl, MVT::f32, Op, + DAG.getConstantFP(numbers::log2ef, dl, MVT::f32)); + return getLimitedPrecisionExp2(t0, dl, DAG); + } + + // No special expansion. + return DAG.getNode(ISD::FEXP, dl, Op.getValueType(), Op); +} + +/// expandLog - Lower a log intrinsic. Handles the special sequences for +/// limited-precision mode. +static SDValue expandLog(const SDLoc &dl, SDValue Op, SelectionDAG &DAG, + const TargetLowering &TLI) { + // TODO: What fast-math-flags should be set on the floating-point nodes? + + if (Op.getValueType() == MVT::f32 && + LimitFloatPrecision > 0 && LimitFloatPrecision <= 18) { + SDValue Op1 = DAG.getNode(ISD::BITCAST, dl, MVT::i32, Op); + + // Scale the exponent by log(2). + SDValue Exp = GetExponent(DAG, Op1, TLI, dl); + SDValue LogOfExponent = + DAG.getNode(ISD::FMUL, dl, MVT::f32, Exp, + DAG.getConstantFP(numbers::ln2f, dl, MVT::f32)); + + // Get the significand and build it into a floating-point number with + // exponent of 1. + SDValue X = GetSignificand(DAG, Op1, dl); + + SDValue LogOfMantissa; + if (LimitFloatPrecision <= 6) { + // For floating-point precision of 6: + // + // LogofMantissa = + // -1.1609546f + + // (1.4034025f - 0.23903021f * x) * x; + // + // error 0.0034276066, which is better than 8 bits + SDValue t0 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X, + getF32Constant(DAG, 0xbe74c456, dl)); + SDValue t1 = DAG.getNode(ISD::FADD, dl, MVT::f32, t0, + getF32Constant(DAG, 0x3fb3a2b1, dl)); + SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t1, X); + LogOfMantissa = DAG.getNode(ISD::FSUB, dl, MVT::f32, t2, + getF32Constant(DAG, 0x3f949a29, dl)); + } else if (LimitFloatPrecision <= 12) { + // For floating-point precision of 12: + // + // LogOfMantissa = + // -1.7417939f + + // (2.8212026f + + // (-1.4699568f + + // (0.44717955f - 0.56570851e-1f * x) * x) * x) * x; + // + // error 0.000061011436, which is 14 bits + SDValue t0 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X, + getF32Constant(DAG, 0xbd67b6d6, dl)); + SDValue t1 = DAG.getNode(ISD::FADD, dl, MVT::f32, t0, + getF32Constant(DAG, 0x3ee4f4b8, dl)); + SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t1, X); + SDValue t3 = DAG.getNode(ISD::FSUB, dl, MVT::f32, t2, + getF32Constant(DAG, 0x3fbc278b, dl)); + SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X); + SDValue t5 = DAG.getNode(ISD::FADD, dl, MVT::f32, t4, + getF32Constant(DAG, 0x40348e95, dl)); + SDValue t6 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t5, X); + LogOfMantissa = DAG.getNode(ISD::FSUB, dl, MVT::f32, t6, + getF32Constant(DAG, 0x3fdef31a, dl)); + } else { // LimitFloatPrecision <= 18 + // For floating-point precision of 18: + // + // LogOfMantissa = + // -2.1072184f + + // (4.2372794f + + // (-3.7029485f + + // (2.2781945f + + // (-0.87823314f + + // (0.19073739f - 0.17809712e-1f * x) * x) * x) * x) * x)*x; + // + // error 0.0000023660568, which is better than 18 bits + SDValue t0 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X, + getF32Constant(DAG, 0xbc91e5ac, dl)); + SDValue t1 = DAG.getNode(ISD::FADD, dl, MVT::f32, t0, + getF32Constant(DAG, 0x3e4350aa, dl)); + SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t1, X); + SDValue t3 = DAG.getNode(ISD::FSUB, dl, MVT::f32, t2, + getF32Constant(DAG, 0x3f60d3e3, dl)); + SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X); + SDValue t5 = DAG.getNode(ISD::FADD, dl, MVT::f32, t4, + getF32Constant(DAG, 0x4011cdf0, dl)); + SDValue t6 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t5, X); + SDValue t7 = DAG.getNode(ISD::FSUB, dl, MVT::f32, t6, + getF32Constant(DAG, 0x406cfd1c, dl)); + SDValue t8 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t7, X); + SDValue t9 = DAG.getNode(ISD::FADD, dl, MVT::f32, t8, + getF32Constant(DAG, 0x408797cb, dl)); + SDValue t10 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t9, X); + LogOfMantissa = DAG.getNode(ISD::FSUB, dl, MVT::f32, t10, + getF32Constant(DAG, 0x4006dcab, dl)); + } + + return DAG.getNode(ISD::FADD, dl, MVT::f32, LogOfExponent, LogOfMantissa); + } + + // No special expansion. + return DAG.getNode(ISD::FLOG, dl, Op.getValueType(), Op); +} + +/// expandLog2 - Lower a log2 intrinsic. Handles the special sequences for +/// limited-precision mode. +static SDValue expandLog2(const SDLoc &dl, SDValue Op, SelectionDAG &DAG, + const TargetLowering &TLI) { + // TODO: What fast-math-flags should be set on the floating-point nodes? + + if (Op.getValueType() == MVT::f32 && + LimitFloatPrecision > 0 && LimitFloatPrecision <= 18) { + SDValue Op1 = DAG.getNode(ISD::BITCAST, dl, MVT::i32, Op); + + // Get the exponent. + SDValue LogOfExponent = GetExponent(DAG, Op1, TLI, dl); + + // Get the significand and build it into a floating-point number with + // exponent of 1. + SDValue X = GetSignificand(DAG, Op1, dl); + + // Different possible minimax approximations of significand in + // floating-point for various degrees of accuracy over [1,2]. + SDValue Log2ofMantissa; + if (LimitFloatPrecision <= 6) { + // For floating-point precision of 6: + // + // Log2ofMantissa = -1.6749035f + (2.0246817f - .34484768f * x) * x; + // + // error 0.0049451742, which is more than 7 bits + SDValue t0 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X, + getF32Constant(DAG, 0xbeb08fe0, dl)); + SDValue t1 = DAG.getNode(ISD::FADD, dl, MVT::f32, t0, + getF32Constant(DAG, 0x40019463, dl)); + SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t1, X); + Log2ofMantissa = DAG.getNode(ISD::FSUB, dl, MVT::f32, t2, + getF32Constant(DAG, 0x3fd6633d, dl)); + } else if (LimitFloatPrecision <= 12) { + // For floating-point precision of 12: + // + // Log2ofMantissa = + // -2.51285454f + + // (4.07009056f + + // (-2.12067489f + + // (.645142248f - 0.816157886e-1f * x) * x) * x) * x; + // + // error 0.0000876136000, which is better than 13 bits + SDValue t0 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X, + getF32Constant(DAG, 0xbda7262e, dl)); + SDValue t1 = DAG.getNode(ISD::FADD, dl, MVT::f32, t0, + getF32Constant(DAG, 0x3f25280b, dl)); + SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t1, X); + SDValue t3 = DAG.getNode(ISD::FSUB, dl, MVT::f32, t2, + getF32Constant(DAG, 0x4007b923, dl)); + SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X); + SDValue t5 = DAG.getNode(ISD::FADD, dl, MVT::f32, t4, + getF32Constant(DAG, 0x40823e2f, dl)); + SDValue t6 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t5, X); + Log2ofMantissa = DAG.getNode(ISD::FSUB, dl, MVT::f32, t6, + getF32Constant(DAG, 0x4020d29c, dl)); + } else { // LimitFloatPrecision <= 18 + // For floating-point precision of 18: + // + // Log2ofMantissa = + // -3.0400495f + + // (6.1129976f + + // (-5.3420409f + + // (3.2865683f + + // (-1.2669343f + + // (0.27515199f - + // 0.25691327e-1f * x) * x) * x) * x) * x) * x; + // + // error 0.0000018516, which is better than 18 bits + SDValue t0 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X, + getF32Constant(DAG, 0xbcd2769e, dl)); + SDValue t1 = DAG.getNode(ISD::FADD, dl, MVT::f32, t0, + getF32Constant(DAG, 0x3e8ce0b9, dl)); + SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t1, X); + SDValue t3 = DAG.getNode(ISD::FSUB, dl, MVT::f32, t2, + getF32Constant(DAG, 0x3fa22ae7, dl)); + SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X); + SDValue t5 = DAG.getNode(ISD::FADD, dl, MVT::f32, t4, + getF32Constant(DAG, 0x40525723, dl)); + SDValue t6 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t5, X); + SDValue t7 = DAG.getNode(ISD::FSUB, dl, MVT::f32, t6, + getF32Constant(DAG, 0x40aaf200, dl)); + SDValue t8 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t7, X); + SDValue t9 = DAG.getNode(ISD::FADD, dl, MVT::f32, t8, + getF32Constant(DAG, 0x40c39dad, dl)); + SDValue t10 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t9, X); + Log2ofMantissa = DAG.getNode(ISD::FSUB, dl, MVT::f32, t10, + getF32Constant(DAG, 0x4042902c, dl)); + } + + return DAG.getNode(ISD::FADD, dl, MVT::f32, LogOfExponent, Log2ofMantissa); + } + + // No special expansion. + return DAG.getNode(ISD::FLOG2, dl, Op.getValueType(), Op); +} + +/// expandLog10 - Lower a log10 intrinsic. Handles the special sequences for +/// limited-precision mode. +static SDValue expandLog10(const SDLoc &dl, SDValue Op, SelectionDAG &DAG, + const TargetLowering &TLI) { + // TODO: What fast-math-flags should be set on the floating-point nodes? + + if (Op.getValueType() == MVT::f32 && + LimitFloatPrecision > 0 && LimitFloatPrecision <= 18) { + SDValue Op1 = DAG.getNode(ISD::BITCAST, dl, MVT::i32, Op); + + // Scale the exponent by log10(2) [0.30102999f]. + SDValue Exp = GetExponent(DAG, Op1, TLI, dl); + SDValue LogOfExponent = DAG.getNode(ISD::FMUL, dl, MVT::f32, Exp, + getF32Constant(DAG, 0x3e9a209a, dl)); + + // Get the significand and build it into a floating-point number with + // exponent of 1. + SDValue X = GetSignificand(DAG, Op1, dl); + + SDValue Log10ofMantissa; + if (LimitFloatPrecision <= 6) { + // For floating-point precision of 6: + // + // Log10ofMantissa = + // -0.50419619f + + // (0.60948995f - 0.10380950f * x) * x; + // + // error 0.0014886165, which is 6 bits + SDValue t0 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X, + getF32Constant(DAG, 0xbdd49a13, dl)); + SDValue t1 = DAG.getNode(ISD::FADD, dl, MVT::f32, t0, + getF32Constant(DAG, 0x3f1c0789, dl)); + SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t1, X); + Log10ofMantissa = DAG.getNode(ISD::FSUB, dl, MVT::f32, t2, + getF32Constant(DAG, 0x3f011300, dl)); + } else if (LimitFloatPrecision <= 12) { + // For floating-point precision of 12: + // + // Log10ofMantissa = + // -0.64831180f + + // (0.91751397f + + // (-0.31664806f + 0.47637168e-1f * x) * x) * x; + // + // error 0.00019228036, which is better than 12 bits + SDValue t0 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X, + getF32Constant(DAG, 0x3d431f31, dl)); + SDValue t1 = DAG.getNode(ISD::FSUB, dl, MVT::f32, t0, + getF32Constant(DAG, 0x3ea21fb2, dl)); + SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t1, X); + SDValue t3 = DAG.getNode(ISD::FADD, dl, MVT::f32, t2, + getF32Constant(DAG, 0x3f6ae232, dl)); + SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X); + Log10ofMantissa = DAG.getNode(ISD::FSUB, dl, MVT::f32, t4, + getF32Constant(DAG, 0x3f25f7c3, dl)); + } else { // LimitFloatPrecision <= 18 + // For floating-point precision of 18: + // + // Log10ofMantissa = + // -0.84299375f + + // (1.5327582f + + // (-1.0688956f + + // (0.49102474f + + // (-0.12539807f + 0.13508273e-1f * x) * x) * x) * x) * x; + // + // error 0.0000037995730, which is better than 18 bits + SDValue t0 = DAG.getNode(ISD::FMUL, dl, MVT::f32, X, + getF32Constant(DAG, 0x3c5d51ce, dl)); + SDValue t1 = DAG.getNode(ISD::FSUB, dl, MVT::f32, t0, + getF32Constant(DAG, 0x3e00685a, dl)); + SDValue t2 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t1, X); + SDValue t3 = DAG.getNode(ISD::FADD, dl, MVT::f32, t2, + getF32Constant(DAG, 0x3efb6798, dl)); + SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X); + SDValue t5 = DAG.getNode(ISD::FSUB, dl, MVT::f32, t4, + getF32Constant(DAG, 0x3f88d192, dl)); + SDValue t6 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t5, X); + SDValue t7 = DAG.getNode(ISD::FADD, dl, MVT::f32, t6, + getF32Constant(DAG, 0x3fc4316c, dl)); + SDValue t8 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t7, X); + Log10ofMantissa = DAG.getNode(ISD::FSUB, dl, MVT::f32, t8, + getF32Constant(DAG, 0x3f57ce70, dl)); + } + + return DAG.getNode(ISD::FADD, dl, MVT::f32, LogOfExponent, Log10ofMantissa); + } + + // No special expansion. + return DAG.getNode(ISD::FLOG10, dl, Op.getValueType(), Op); +} + +/// expandExp2 - Lower an exp2 intrinsic. Handles the special sequences for +/// limited-precision mode. +static SDValue expandExp2(const SDLoc &dl, SDValue Op, SelectionDAG &DAG, + const TargetLowering &TLI) { + if (Op.getValueType() == MVT::f32 && + LimitFloatPrecision > 0 && LimitFloatPrecision <= 18) + return getLimitedPrecisionExp2(Op, dl, DAG); + + // No special expansion. + return DAG.getNode(ISD::FEXP2, dl, Op.getValueType(), Op); +} + +/// visitPow - Lower a pow intrinsic. Handles the special sequences for +/// limited-precision mode with x == 10.0f. +static SDValue expandPow(const SDLoc &dl, SDValue LHS, SDValue RHS, + SelectionDAG &DAG, const TargetLowering &TLI) { + bool IsExp10 = false; + if (LHS.getValueType() == MVT::f32 && RHS.getValueType() == MVT::f32 && + LimitFloatPrecision > 0 && LimitFloatPrecision <= 18) { + if (ConstantFPSDNode *LHSC = dyn_cast<ConstantFPSDNode>(LHS)) { + APFloat Ten(10.0f); + IsExp10 = LHSC->isExactlyValue(Ten); + } + } + + // TODO: What fast-math-flags should be set on the FMUL node? + if (IsExp10) { + // Put the exponent in the right bit position for later addition to the + // final result: + // + // #define LOG2OF10 3.3219281f + // t0 = Op * LOG2OF10; + SDValue t0 = DAG.getNode(ISD::FMUL, dl, MVT::f32, RHS, + getF32Constant(DAG, 0x40549a78, dl)); + return getLimitedPrecisionExp2(t0, dl, DAG); + } + + // No special expansion. + return DAG.getNode(ISD::FPOW, dl, LHS.getValueType(), LHS, RHS); +} + +/// ExpandPowI - Expand a llvm.powi intrinsic. +static SDValue ExpandPowI(const SDLoc &DL, SDValue LHS, SDValue RHS, + SelectionDAG &DAG) { + // If RHS is a constant, we can expand this out to a multiplication tree, + // otherwise we end up lowering to a call to __powidf2 (for example). When + // optimizing for size, we only want to do this if the expansion would produce + // a small number of multiplies, otherwise we do the full expansion. + if (ConstantSDNode *RHSC = dyn_cast<ConstantSDNode>(RHS)) { + // Get the exponent as a positive value. + unsigned Val = RHSC->getSExtValue(); + if ((int)Val < 0) Val = -Val; + + // powi(x, 0) -> 1.0 + if (Val == 0) + return DAG.getConstantFP(1.0, DL, LHS.getValueType()); + + bool OptForSize = DAG.shouldOptForSize(); + if (!OptForSize || + // If optimizing for size, don't insert too many multiplies. + // This inserts up to 5 multiplies. + countPopulation(Val) + Log2_32(Val) < 7) { + // We use the simple binary decomposition method to generate the multiply + // sequence. There are more optimal ways to do this (for example, + // powi(x,15) generates one more multiply than it should), but this has + // the benefit of being both really simple and much better than a libcall. + SDValue Res; // Logically starts equal to 1.0 + SDValue CurSquare = LHS; + // TODO: Intrinsics should have fast-math-flags that propagate to these + // nodes. + while (Val) { + if (Val & 1) { + if (Res.getNode()) + Res = DAG.getNode(ISD::FMUL, DL,Res.getValueType(), Res, CurSquare); + else + Res = CurSquare; // 1.0*CurSquare. + } + + CurSquare = DAG.getNode(ISD::FMUL, DL, CurSquare.getValueType(), + CurSquare, CurSquare); + Val >>= 1; + } + + // If the original was negative, invert the result, producing 1/(x*x*x). + if (RHSC->getSExtValue() < 0) + Res = DAG.getNode(ISD::FDIV, DL, LHS.getValueType(), + DAG.getConstantFP(1.0, DL, LHS.getValueType()), Res); + return Res; + } + } + + // Otherwise, expand to a libcall. + return DAG.getNode(ISD::FPOWI, DL, LHS.getValueType(), LHS, RHS); +} + +static SDValue expandDivFix(unsigned Opcode, const SDLoc &DL, + SDValue LHS, SDValue RHS, SDValue Scale, + SelectionDAG &DAG, const TargetLowering &TLI) { + EVT VT = LHS.getValueType(); + bool Signed = Opcode == ISD::SDIVFIX; + LLVMContext &Ctx = *DAG.getContext(); + + // If the type is legal but the operation isn't, this node might survive all + // the way to operation legalization. If we end up there and we do not have + // the ability to widen the type (if VT*2 is not legal), we cannot expand the + // node. + + // Coax the legalizer into expanding the node during type legalization instead + // by bumping the size by one bit. This will force it to Promote, enabling the + // early expansion and avoiding the need to expand later. + + // We don't have to do this if Scale is 0; that can always be expanded. + + // FIXME: We wouldn't have to do this (or any of the early + // expansion/promotion) if it was possible to expand a libcall of an + // illegal type during operation legalization. But it's not, so things + // get a bit hacky. + unsigned ScaleInt = cast<ConstantSDNode>(Scale)->getZExtValue(); + if (ScaleInt > 0 && + (TLI.isTypeLegal(VT) || + (VT.isVector() && TLI.isTypeLegal(VT.getVectorElementType())))) { + TargetLowering::LegalizeAction Action = TLI.getFixedPointOperationAction( + Opcode, VT, ScaleInt); + if (Action != TargetLowering::Legal && Action != TargetLowering::Custom) { + EVT PromVT; + if (VT.isScalarInteger()) + PromVT = EVT::getIntegerVT(Ctx, VT.getSizeInBits() + 1); + else if (VT.isVector()) { + PromVT = VT.getVectorElementType(); + PromVT = EVT::getIntegerVT(Ctx, PromVT.getSizeInBits() + 1); + PromVT = EVT::getVectorVT(Ctx, PromVT, VT.getVectorElementCount()); + } else + llvm_unreachable("Wrong VT for DIVFIX?"); + if (Signed) { + LHS = DAG.getSExtOrTrunc(LHS, DL, PromVT); + RHS = DAG.getSExtOrTrunc(RHS, DL, PromVT); + } else { + LHS = DAG.getZExtOrTrunc(LHS, DL, PromVT); + RHS = DAG.getZExtOrTrunc(RHS, DL, PromVT); + } + // TODO: Saturation. + SDValue Res = DAG.getNode(Opcode, DL, PromVT, LHS, RHS, Scale); + return DAG.getZExtOrTrunc(Res, DL, VT); + } + } + + return DAG.getNode(Opcode, DL, VT, LHS, RHS, Scale); +} + +// getUnderlyingArgRegs - Find underlying registers used for a truncated, +// bitcasted, or split argument. Returns a list of <Register, size in bits> +static void +getUnderlyingArgRegs(SmallVectorImpl<std::pair<unsigned, unsigned>> &Regs, + const SDValue &N) { + switch (N.getOpcode()) { + case ISD::CopyFromReg: { + SDValue Op = N.getOperand(1); + Regs.emplace_back(cast<RegisterSDNode>(Op)->getReg(), + Op.getValueType().getSizeInBits()); + return; + } + case ISD::BITCAST: + case ISD::AssertZext: + case ISD::AssertSext: + case ISD::TRUNCATE: + getUnderlyingArgRegs(Regs, N.getOperand(0)); + return; + case ISD::BUILD_PAIR: + case ISD::BUILD_VECTOR: + case ISD::CONCAT_VECTORS: + for (SDValue Op : N->op_values()) + getUnderlyingArgRegs(Regs, Op); + return; + default: + return; + } +} + +/// If the DbgValueInst is a dbg_value of a function argument, create the +/// corresponding DBG_VALUE machine instruction for it now. At the end of +/// instruction selection, they will be inserted to the entry BB. +bool SelectionDAGBuilder::EmitFuncArgumentDbgValue( + const Value *V, DILocalVariable *Variable, DIExpression *Expr, + DILocation *DL, bool IsDbgDeclare, const SDValue &N) { + const Argument *Arg = dyn_cast<Argument>(V); + if (!Arg) + return false; + + if (!IsDbgDeclare) { + // ArgDbgValues are hoisted to the beginning of the entry block. So we + // should only emit as ArgDbgValue if the dbg.value intrinsic is found in + // the entry block. + bool IsInEntryBlock = FuncInfo.MBB == &FuncInfo.MF->front(); + if (!IsInEntryBlock) + return false; + + // ArgDbgValues are hoisted to the beginning of the entry block. So we + // should only emit as ArgDbgValue if the dbg.value intrinsic describes a + // variable that also is a param. + // + // Although, if we are at the top of the entry block already, we can still + // emit using ArgDbgValue. This might catch some situations when the + // dbg.value refers to an argument that isn't used in the entry block, so + // any CopyToReg node would be optimized out and the only way to express + // this DBG_VALUE is by using the physical reg (or FI) as done in this + // method. ArgDbgValues are hoisted to the beginning of the entry block. So + // we should only emit as ArgDbgValue if the Variable is an argument to the + // current function, and the dbg.value intrinsic is found in the entry + // block. + bool VariableIsFunctionInputArg = Variable->isParameter() && + !DL->getInlinedAt(); + bool IsInPrologue = SDNodeOrder == LowestSDNodeOrder; + if (!IsInPrologue && !VariableIsFunctionInputArg) + return false; + + // Here we assume that a function argument on IR level only can be used to + // describe one input parameter on source level. If we for example have + // source code like this + // + // struct A { long x, y; }; + // void foo(struct A a, long b) { + // ... + // b = a.x; + // ... + // } + // + // and IR like this + // + // define void @foo(i32 %a1, i32 %a2, i32 %b) { + // entry: + // call void @llvm.dbg.value(metadata i32 %a1, "a", DW_OP_LLVM_fragment + // call void @llvm.dbg.value(metadata i32 %a2, "a", DW_OP_LLVM_fragment + // call void @llvm.dbg.value(metadata i32 %b, "b", + // ... + // call void @llvm.dbg.value(metadata i32 %a1, "b" + // ... + // + // then the last dbg.value is describing a parameter "b" using a value that + // is an argument. But since we already has used %a1 to describe a parameter + // we should not handle that last dbg.value here (that would result in an + // incorrect hoisting of the DBG_VALUE to the function entry). + // Notice that we allow one dbg.value per IR level argument, to accommodate + // for the situation with fragments above. + if (VariableIsFunctionInputArg) { + unsigned ArgNo = Arg->getArgNo(); + if (ArgNo >= FuncInfo.DescribedArgs.size()) + FuncInfo.DescribedArgs.resize(ArgNo + 1, false); + else if (!IsInPrologue && FuncInfo.DescribedArgs.test(ArgNo)) + return false; + FuncInfo.DescribedArgs.set(ArgNo); + } + } + + MachineFunction &MF = DAG.getMachineFunction(); + const TargetInstrInfo *TII = DAG.getSubtarget().getInstrInfo(); + + bool IsIndirect = false; + Optional<MachineOperand> Op; + // Some arguments' frame index is recorded during argument lowering. + int FI = FuncInfo.getArgumentFrameIndex(Arg); + if (FI != std::numeric_limits<int>::max()) + Op = MachineOperand::CreateFI(FI); + + SmallVector<std::pair<unsigned, unsigned>, 8> ArgRegsAndSizes; + if (!Op && N.getNode()) { + getUnderlyingArgRegs(ArgRegsAndSizes, N); + Register Reg; + if (ArgRegsAndSizes.size() == 1) + Reg = ArgRegsAndSizes.front().first; + + if (Reg && Reg.isVirtual()) { + MachineRegisterInfo &RegInfo = MF.getRegInfo(); + Register PR = RegInfo.getLiveInPhysReg(Reg); + if (PR) + Reg = PR; + } + if (Reg) { + Op = MachineOperand::CreateReg(Reg, false); + IsIndirect = IsDbgDeclare; + } + } + + if (!Op && N.getNode()) { + // Check if frame index is available. + SDValue LCandidate = peekThroughBitcasts(N); + if (LoadSDNode *LNode = dyn_cast<LoadSDNode>(LCandidate.getNode())) + if (FrameIndexSDNode *FINode = + dyn_cast<FrameIndexSDNode>(LNode->getBasePtr().getNode())) + Op = MachineOperand::CreateFI(FINode->getIndex()); + } + + if (!Op) { + // Create a DBG_VALUE for each decomposed value in ArgRegs to cover Reg + auto splitMultiRegDbgValue + = [&](ArrayRef<std::pair<unsigned, unsigned>> SplitRegs) { + unsigned Offset = 0; + for (auto RegAndSize : SplitRegs) { + // If the expression is already a fragment, the current register + // offset+size might extend beyond the fragment. In this case, only + // the register bits that are inside the fragment are relevant. + int RegFragmentSizeInBits = RegAndSize.second; + if (auto ExprFragmentInfo = Expr->getFragmentInfo()) { + uint64_t ExprFragmentSizeInBits = ExprFragmentInfo->SizeInBits; + // The register is entirely outside the expression fragment, + // so is irrelevant for debug info. + if (Offset >= ExprFragmentSizeInBits) + break; + // The register is partially outside the expression fragment, only + // the low bits within the fragment are relevant for debug info. + if (Offset + RegFragmentSizeInBits > ExprFragmentSizeInBits) { + RegFragmentSizeInBits = ExprFragmentSizeInBits - Offset; + } + } + + auto FragmentExpr = DIExpression::createFragmentExpression( + Expr, Offset, RegFragmentSizeInBits); + Offset += RegAndSize.second; + // If a valid fragment expression cannot be created, the variable's + // correct value cannot be determined and so it is set as Undef. + if (!FragmentExpr) { + SDDbgValue *SDV = DAG.getConstantDbgValue( + Variable, Expr, UndefValue::get(V->getType()), DL, SDNodeOrder); + DAG.AddDbgValue(SDV, nullptr, false); + continue; + } + assert(!IsDbgDeclare && "DbgDeclare operand is not in memory?"); + FuncInfo.ArgDbgValues.push_back( + BuildMI(MF, DL, TII->get(TargetOpcode::DBG_VALUE), IsDbgDeclare, + RegAndSize.first, Variable, *FragmentExpr)); + } + }; + + // Check if ValueMap has reg number. + DenseMap<const Value *, unsigned>::const_iterator + VMI = FuncInfo.ValueMap.find(V); + if (VMI != FuncInfo.ValueMap.end()) { + const auto &TLI = DAG.getTargetLoweringInfo(); + RegsForValue RFV(V->getContext(), TLI, DAG.getDataLayout(), VMI->second, + V->getType(), getABIRegCopyCC(V)); + if (RFV.occupiesMultipleRegs()) { + splitMultiRegDbgValue(RFV.getRegsAndSizes()); + return true; + } + + Op = MachineOperand::CreateReg(VMI->second, false); + IsIndirect = IsDbgDeclare; + } else if (ArgRegsAndSizes.size() > 1) { + // This was split due to the calling convention, and no virtual register + // mapping exists for the value. + splitMultiRegDbgValue(ArgRegsAndSizes); + return true; + } + } + + if (!Op) + return false; + + assert(Variable->isValidLocationForIntrinsic(DL) && + "Expected inlined-at fields to agree"); + IsIndirect = (Op->isReg()) ? IsIndirect : true; + FuncInfo.ArgDbgValues.push_back( + BuildMI(MF, DL, TII->get(TargetOpcode::DBG_VALUE), IsIndirect, + *Op, Variable, Expr)); + + return true; +} + +/// Return the appropriate SDDbgValue based on N. +SDDbgValue *SelectionDAGBuilder::getDbgValue(SDValue N, + DILocalVariable *Variable, + DIExpression *Expr, + const DebugLoc &dl, + unsigned DbgSDNodeOrder) { + if (auto *FISDN = dyn_cast<FrameIndexSDNode>(N.getNode())) { + // Construct a FrameIndexDbgValue for FrameIndexSDNodes so we can describe + // stack slot locations. + // + // Consider "int x = 0; int *px = &x;". There are two kinds of interesting + // debug values here after optimization: + // + // dbg.value(i32* %px, !"int *px", !DIExpression()), and + // dbg.value(i32* %px, !"int x", !DIExpression(DW_OP_deref)) + // + // Both describe the direct values of their associated variables. + return DAG.getFrameIndexDbgValue(Variable, Expr, FISDN->getIndex(), + /*IsIndirect*/ false, dl, DbgSDNodeOrder); + } + return DAG.getDbgValue(Variable, Expr, N.getNode(), N.getResNo(), + /*IsIndirect*/ false, dl, DbgSDNodeOrder); +} + +static unsigned FixedPointIntrinsicToOpcode(unsigned Intrinsic) { + switch (Intrinsic) { + case Intrinsic::smul_fix: + return ISD::SMULFIX; + case Intrinsic::umul_fix: + return ISD::UMULFIX; + case Intrinsic::smul_fix_sat: + return ISD::SMULFIXSAT; + case Intrinsic::umul_fix_sat: + return ISD::UMULFIXSAT; + case Intrinsic::sdiv_fix: + return ISD::SDIVFIX; + case Intrinsic::udiv_fix: + return ISD::UDIVFIX; + default: + llvm_unreachable("Unhandled fixed point intrinsic"); + } +} + +void SelectionDAGBuilder::lowerCallToExternalSymbol(const CallInst &I, + const char *FunctionName) { + assert(FunctionName && "FunctionName must not be nullptr"); + SDValue Callee = DAG.getExternalSymbol( + FunctionName, + DAG.getTargetLoweringInfo().getPointerTy(DAG.getDataLayout())); + LowerCallTo(&I, Callee, I.isTailCall()); +} + +/// Lower the call to the specified intrinsic function. +void SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I, + unsigned Intrinsic) { + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + SDLoc sdl = getCurSDLoc(); + DebugLoc dl = getCurDebugLoc(); + SDValue Res; + + switch (Intrinsic) { + default: + // By default, turn this into a target intrinsic node. + visitTargetIntrinsic(I, Intrinsic); + return; + case Intrinsic::vastart: visitVAStart(I); return; + case Intrinsic::vaend: visitVAEnd(I); return; + case Intrinsic::vacopy: visitVACopy(I); return; + case Intrinsic::returnaddress: + setValue(&I, DAG.getNode(ISD::RETURNADDR, sdl, + TLI.getPointerTy(DAG.getDataLayout()), + getValue(I.getArgOperand(0)))); + return; + case Intrinsic::addressofreturnaddress: + setValue(&I, DAG.getNode(ISD::ADDROFRETURNADDR, sdl, + TLI.getPointerTy(DAG.getDataLayout()))); + return; + case Intrinsic::sponentry: + setValue(&I, DAG.getNode(ISD::SPONENTRY, sdl, + TLI.getFrameIndexTy(DAG.getDataLayout()))); + return; + case Intrinsic::frameaddress: + setValue(&I, DAG.getNode(ISD::FRAMEADDR, sdl, + TLI.getFrameIndexTy(DAG.getDataLayout()), + getValue(I.getArgOperand(0)))); + return; + case Intrinsic::read_register: { + Value *Reg = I.getArgOperand(0); + SDValue Chain = getRoot(); + SDValue RegName = + DAG.getMDNode(cast<MDNode>(cast<MetadataAsValue>(Reg)->getMetadata())); + EVT VT = TLI.getValueType(DAG.getDataLayout(), I.getType()); + Res = DAG.getNode(ISD::READ_REGISTER, sdl, + DAG.getVTList(VT, MVT::Other), Chain, RegName); + setValue(&I, Res); + DAG.setRoot(Res.getValue(1)); + return; + } + case Intrinsic::write_register: { + Value *Reg = I.getArgOperand(0); + Value *RegValue = I.getArgOperand(1); + SDValue Chain = getRoot(); + SDValue RegName = + DAG.getMDNode(cast<MDNode>(cast<MetadataAsValue>(Reg)->getMetadata())); + DAG.setRoot(DAG.getNode(ISD::WRITE_REGISTER, sdl, MVT::Other, Chain, + RegName, getValue(RegValue))); + return; + } + case Intrinsic::memcpy: { + const auto &MCI = cast<MemCpyInst>(I); + SDValue Op1 = getValue(I.getArgOperand(0)); + SDValue Op2 = getValue(I.getArgOperand(1)); + SDValue Op3 = getValue(I.getArgOperand(2)); + // @llvm.memcpy defines 0 and 1 to both mean no alignment. + unsigned DstAlign = std::max<unsigned>(MCI.getDestAlignment(), 1); + unsigned SrcAlign = std::max<unsigned>(MCI.getSourceAlignment(), 1); + unsigned Align = MinAlign(DstAlign, SrcAlign); + bool isVol = MCI.isVolatile(); + bool isTC = I.isTailCall() && isInTailCallPosition(&I, DAG.getTarget()); + // FIXME: Support passing different dest/src alignments to the memcpy DAG + // node. + SDValue Root = isVol ? getRoot() : getMemoryRoot(); + SDValue MC = DAG.getMemcpy(Root, sdl, Op1, Op2, Op3, Align, isVol, + false, isTC, + MachinePointerInfo(I.getArgOperand(0)), + MachinePointerInfo(I.getArgOperand(1))); + updateDAGForMaybeTailCall(MC); + return; + } + case Intrinsic::memset: { + const auto &MSI = cast<MemSetInst>(I); + SDValue Op1 = getValue(I.getArgOperand(0)); + SDValue Op2 = getValue(I.getArgOperand(1)); + SDValue Op3 = getValue(I.getArgOperand(2)); + // @llvm.memset defines 0 and 1 to both mean no alignment. + unsigned Align = std::max<unsigned>(MSI.getDestAlignment(), 1); + bool isVol = MSI.isVolatile(); + bool isTC = I.isTailCall() && isInTailCallPosition(&I, DAG.getTarget()); + SDValue Root = isVol ? getRoot() : getMemoryRoot(); + SDValue MS = DAG.getMemset(Root, sdl, Op1, Op2, Op3, Align, isVol, + isTC, MachinePointerInfo(I.getArgOperand(0))); + updateDAGForMaybeTailCall(MS); + return; + } + case Intrinsic::memmove: { + const auto &MMI = cast<MemMoveInst>(I); + SDValue Op1 = getValue(I.getArgOperand(0)); + SDValue Op2 = getValue(I.getArgOperand(1)); + SDValue Op3 = getValue(I.getArgOperand(2)); + // @llvm.memmove defines 0 and 1 to both mean no alignment. + unsigned DstAlign = std::max<unsigned>(MMI.getDestAlignment(), 1); + unsigned SrcAlign = std::max<unsigned>(MMI.getSourceAlignment(), 1); + unsigned Align = MinAlign(DstAlign, SrcAlign); + bool isVol = MMI.isVolatile(); + bool isTC = I.isTailCall() && isInTailCallPosition(&I, DAG.getTarget()); + // FIXME: Support passing different dest/src alignments to the memmove DAG + // node. + SDValue Root = isVol ? getRoot() : getMemoryRoot(); + SDValue MM = DAG.getMemmove(Root, sdl, Op1, Op2, Op3, Align, isVol, + isTC, MachinePointerInfo(I.getArgOperand(0)), + MachinePointerInfo(I.getArgOperand(1))); + updateDAGForMaybeTailCall(MM); + return; + } + case Intrinsic::memcpy_element_unordered_atomic: { + const AtomicMemCpyInst &MI = cast<AtomicMemCpyInst>(I); + SDValue Dst = getValue(MI.getRawDest()); + SDValue Src = getValue(MI.getRawSource()); + SDValue Length = getValue(MI.getLength()); + + unsigned DstAlign = MI.getDestAlignment(); + unsigned SrcAlign = MI.getSourceAlignment(); + Type *LengthTy = MI.getLength()->getType(); + unsigned ElemSz = MI.getElementSizeInBytes(); + bool isTC = I.isTailCall() && isInTailCallPosition(&I, DAG.getTarget()); + SDValue MC = DAG.getAtomicMemcpy(getRoot(), sdl, Dst, DstAlign, Src, + SrcAlign, Length, LengthTy, ElemSz, isTC, + MachinePointerInfo(MI.getRawDest()), + MachinePointerInfo(MI.getRawSource())); + updateDAGForMaybeTailCall(MC); + return; + } + case Intrinsic::memmove_element_unordered_atomic: { + auto &MI = cast<AtomicMemMoveInst>(I); + SDValue Dst = getValue(MI.getRawDest()); + SDValue Src = getValue(MI.getRawSource()); + SDValue Length = getValue(MI.getLength()); + + unsigned DstAlign = MI.getDestAlignment(); + unsigned SrcAlign = MI.getSourceAlignment(); + Type *LengthTy = MI.getLength()->getType(); + unsigned ElemSz = MI.getElementSizeInBytes(); + bool isTC = I.isTailCall() && isInTailCallPosition(&I, DAG.getTarget()); + SDValue MC = DAG.getAtomicMemmove(getRoot(), sdl, Dst, DstAlign, Src, + SrcAlign, Length, LengthTy, ElemSz, isTC, + MachinePointerInfo(MI.getRawDest()), + MachinePointerInfo(MI.getRawSource())); + updateDAGForMaybeTailCall(MC); + return; + } + case Intrinsic::memset_element_unordered_atomic: { + auto &MI = cast<AtomicMemSetInst>(I); + SDValue Dst = getValue(MI.getRawDest()); + SDValue Val = getValue(MI.getValue()); + SDValue Length = getValue(MI.getLength()); + + unsigned DstAlign = MI.getDestAlignment(); + Type *LengthTy = MI.getLength()->getType(); + unsigned ElemSz = MI.getElementSizeInBytes(); + bool isTC = I.isTailCall() && isInTailCallPosition(&I, DAG.getTarget()); + SDValue MC = DAG.getAtomicMemset(getRoot(), sdl, Dst, DstAlign, Val, Length, + LengthTy, ElemSz, isTC, + MachinePointerInfo(MI.getRawDest())); + updateDAGForMaybeTailCall(MC); + return; + } + case Intrinsic::dbg_addr: + case Intrinsic::dbg_declare: { + const auto &DI = cast<DbgVariableIntrinsic>(I); + DILocalVariable *Variable = DI.getVariable(); + DIExpression *Expression = DI.getExpression(); + dropDanglingDebugInfo(Variable, Expression); + assert(Variable && "Missing variable"); + + // Check if address has undef value. + const Value *Address = DI.getVariableLocation(); + if (!Address || isa<UndefValue>(Address) || + (Address->use_empty() && !isa<Argument>(Address))) { + LLVM_DEBUG(dbgs() << "Dropping debug info for " << DI << "\n"); + return; + } + + bool isParameter = Variable->isParameter() || isa<Argument>(Address); + + // Check if this variable can be described by a frame index, typically + // either as a static alloca or a byval parameter. + int FI = std::numeric_limits<int>::max(); + if (const auto *AI = + dyn_cast<AllocaInst>(Address->stripInBoundsConstantOffsets())) { + if (AI->isStaticAlloca()) { + auto I = FuncInfo.StaticAllocaMap.find(AI); + if (I != FuncInfo.StaticAllocaMap.end()) + FI = I->second; + } + } else if (const auto *Arg = dyn_cast<Argument>( + Address->stripInBoundsConstantOffsets())) { + FI = FuncInfo.getArgumentFrameIndex(Arg); + } + + // llvm.dbg.addr is control dependent and always generates indirect + // DBG_VALUE instructions. llvm.dbg.declare is handled as a frame index in + // the MachineFunction variable table. + if (FI != std::numeric_limits<int>::max()) { + if (Intrinsic == Intrinsic::dbg_addr) { + SDDbgValue *SDV = DAG.getFrameIndexDbgValue( + Variable, Expression, FI, /*IsIndirect*/ true, dl, SDNodeOrder); + DAG.AddDbgValue(SDV, getRoot().getNode(), isParameter); + } + return; + } + + SDValue &N = NodeMap[Address]; + if (!N.getNode() && isa<Argument>(Address)) + // Check unused arguments map. + N = UnusedArgNodeMap[Address]; + SDDbgValue *SDV; + if (N.getNode()) { + if (const BitCastInst *BCI = dyn_cast<BitCastInst>(Address)) + Address = BCI->getOperand(0); + // Parameters are handled specially. + auto FINode = dyn_cast<FrameIndexSDNode>(N.getNode()); + if (isParameter && FINode) { + // Byval parameter. We have a frame index at this point. + SDV = + DAG.getFrameIndexDbgValue(Variable, Expression, FINode->getIndex(), + /*IsIndirect*/ true, dl, SDNodeOrder); + } else if (isa<Argument>(Address)) { + // Address is an argument, so try to emit its dbg value using + // virtual register info from the FuncInfo.ValueMap. + EmitFuncArgumentDbgValue(Address, Variable, Expression, dl, true, N); + return; + } else { + SDV = DAG.getDbgValue(Variable, Expression, N.getNode(), N.getResNo(), + true, dl, SDNodeOrder); + } + DAG.AddDbgValue(SDV, N.getNode(), isParameter); + } else { + // If Address is an argument then try to emit its dbg value using + // virtual register info from the FuncInfo.ValueMap. + if (!EmitFuncArgumentDbgValue(Address, Variable, Expression, dl, true, + N)) { + LLVM_DEBUG(dbgs() << "Dropping debug info for " << DI << "\n"); + } + } + return; + } + case Intrinsic::dbg_label: { + const DbgLabelInst &DI = cast<DbgLabelInst>(I); + DILabel *Label = DI.getLabel(); + assert(Label && "Missing label"); + + SDDbgLabel *SDV; + SDV = DAG.getDbgLabel(Label, dl, SDNodeOrder); + DAG.AddDbgLabel(SDV); + return; + } + case Intrinsic::dbg_value: { + const DbgValueInst &DI = cast<DbgValueInst>(I); + assert(DI.getVariable() && "Missing variable"); + + DILocalVariable *Variable = DI.getVariable(); + DIExpression *Expression = DI.getExpression(); + dropDanglingDebugInfo(Variable, Expression); + const Value *V = DI.getValue(); + if (!V) + return; + + if (handleDebugValue(V, Variable, Expression, dl, DI.getDebugLoc(), + SDNodeOrder)) + return; + + // TODO: Dangling debug info will eventually either be resolved or produce + // an Undef DBG_VALUE. However in the resolution case, a gap may appear + // between the original dbg.value location and its resolved DBG_VALUE, which + // we should ideally fill with an extra Undef DBG_VALUE. + + DanglingDebugInfoMap[V].emplace_back(&DI, dl, SDNodeOrder); + return; + } + + case Intrinsic::eh_typeid_for: { + // Find the type id for the given typeinfo. + GlobalValue *GV = ExtractTypeInfo(I.getArgOperand(0)); + unsigned TypeID = DAG.getMachineFunction().getTypeIDFor(GV); + Res = DAG.getConstant(TypeID, sdl, MVT::i32); + setValue(&I, Res); + return; + } + + case Intrinsic::eh_return_i32: + case Intrinsic::eh_return_i64: + DAG.getMachineFunction().setCallsEHReturn(true); + DAG.setRoot(DAG.getNode(ISD::EH_RETURN, sdl, + MVT::Other, + getControlRoot(), + getValue(I.getArgOperand(0)), + getValue(I.getArgOperand(1)))); + return; + case Intrinsic::eh_unwind_init: + DAG.getMachineFunction().setCallsUnwindInit(true); + return; + case Intrinsic::eh_dwarf_cfa: + setValue(&I, DAG.getNode(ISD::EH_DWARF_CFA, sdl, + TLI.getPointerTy(DAG.getDataLayout()), + getValue(I.getArgOperand(0)))); + return; + case Intrinsic::eh_sjlj_callsite: { + MachineModuleInfo &MMI = DAG.getMachineFunction().getMMI(); + ConstantInt *CI = dyn_cast<ConstantInt>(I.getArgOperand(0)); + assert(CI && "Non-constant call site value in eh.sjlj.callsite!"); + assert(MMI.getCurrentCallSite() == 0 && "Overlapping call sites!"); + + MMI.setCurrentCallSite(CI->getZExtValue()); + return; + } + case Intrinsic::eh_sjlj_functioncontext: { + // Get and store the index of the function context. + MachineFrameInfo &MFI = DAG.getMachineFunction().getFrameInfo(); + AllocaInst *FnCtx = + cast<AllocaInst>(I.getArgOperand(0)->stripPointerCasts()); + int FI = FuncInfo.StaticAllocaMap[FnCtx]; + MFI.setFunctionContextIndex(FI); + return; + } + case Intrinsic::eh_sjlj_setjmp: { + SDValue Ops[2]; + Ops[0] = getRoot(); + Ops[1] = getValue(I.getArgOperand(0)); + SDValue Op = DAG.getNode(ISD::EH_SJLJ_SETJMP, sdl, + DAG.getVTList(MVT::i32, MVT::Other), Ops); + setValue(&I, Op.getValue(0)); + DAG.setRoot(Op.getValue(1)); + return; + } + case Intrinsic::eh_sjlj_longjmp: + DAG.setRoot(DAG.getNode(ISD::EH_SJLJ_LONGJMP, sdl, MVT::Other, + getRoot(), getValue(I.getArgOperand(0)))); + return; + case Intrinsic::eh_sjlj_setup_dispatch: + DAG.setRoot(DAG.getNode(ISD::EH_SJLJ_SETUP_DISPATCH, sdl, MVT::Other, + getRoot())); + return; + case Intrinsic::masked_gather: + visitMaskedGather(I); + return; + case Intrinsic::masked_load: + visitMaskedLoad(I); + return; + case Intrinsic::masked_scatter: + visitMaskedScatter(I); + return; + case Intrinsic::masked_store: + visitMaskedStore(I); + return; + case Intrinsic::masked_expandload: + visitMaskedLoad(I, true /* IsExpanding */); + return; + case Intrinsic::masked_compressstore: + visitMaskedStore(I, true /* IsCompressing */); + return; + case Intrinsic::powi: + setValue(&I, ExpandPowI(sdl, getValue(I.getArgOperand(0)), + getValue(I.getArgOperand(1)), DAG)); + return; + case Intrinsic::log: + setValue(&I, expandLog(sdl, getValue(I.getArgOperand(0)), DAG, TLI)); + return; + case Intrinsic::log2: + setValue(&I, expandLog2(sdl, getValue(I.getArgOperand(0)), DAG, TLI)); + return; + case Intrinsic::log10: + setValue(&I, expandLog10(sdl, getValue(I.getArgOperand(0)), DAG, TLI)); + return; + case Intrinsic::exp: + setValue(&I, expandExp(sdl, getValue(I.getArgOperand(0)), DAG, TLI)); + return; + case Intrinsic::exp2: + setValue(&I, expandExp2(sdl, getValue(I.getArgOperand(0)), DAG, TLI)); + return; + case Intrinsic::pow: + setValue(&I, expandPow(sdl, getValue(I.getArgOperand(0)), + getValue(I.getArgOperand(1)), DAG, TLI)); + return; + case Intrinsic::sqrt: + case Intrinsic::fabs: + case Intrinsic::sin: + case Intrinsic::cos: + case Intrinsic::floor: + case Intrinsic::ceil: + case Intrinsic::trunc: + case Intrinsic::rint: + case Intrinsic::nearbyint: + case Intrinsic::round: + case Intrinsic::canonicalize: { + unsigned Opcode; + switch (Intrinsic) { + default: llvm_unreachable("Impossible intrinsic"); // Can't reach here. + case Intrinsic::sqrt: Opcode = ISD::FSQRT; break; + case Intrinsic::fabs: Opcode = ISD::FABS; break; + case Intrinsic::sin: Opcode = ISD::FSIN; break; + case Intrinsic::cos: Opcode = ISD::FCOS; break; + case Intrinsic::floor: Opcode = ISD::FFLOOR; break; + case Intrinsic::ceil: Opcode = ISD::FCEIL; break; + case Intrinsic::trunc: Opcode = ISD::FTRUNC; break; + case Intrinsic::rint: Opcode = ISD::FRINT; break; + case Intrinsic::nearbyint: Opcode = ISD::FNEARBYINT; break; + case Intrinsic::round: Opcode = ISD::FROUND; break; + case Intrinsic::canonicalize: Opcode = ISD::FCANONICALIZE; break; + } + + setValue(&I, DAG.getNode(Opcode, sdl, + getValue(I.getArgOperand(0)).getValueType(), + getValue(I.getArgOperand(0)))); + return; + } + case Intrinsic::lround: + case Intrinsic::llround: + case Intrinsic::lrint: + case Intrinsic::llrint: { + unsigned Opcode; + switch (Intrinsic) { + default: llvm_unreachable("Impossible intrinsic"); // Can't reach here. + case Intrinsic::lround: Opcode = ISD::LROUND; break; + case Intrinsic::llround: Opcode = ISD::LLROUND; break; + case Intrinsic::lrint: Opcode = ISD::LRINT; break; + case Intrinsic::llrint: Opcode = ISD::LLRINT; break; + } + + EVT RetVT = TLI.getValueType(DAG.getDataLayout(), I.getType()); + setValue(&I, DAG.getNode(Opcode, sdl, RetVT, + getValue(I.getArgOperand(0)))); + return; + } + case Intrinsic::minnum: + setValue(&I, DAG.getNode(ISD::FMINNUM, sdl, + getValue(I.getArgOperand(0)).getValueType(), + getValue(I.getArgOperand(0)), + getValue(I.getArgOperand(1)))); + return; + case Intrinsic::maxnum: + setValue(&I, DAG.getNode(ISD::FMAXNUM, sdl, + getValue(I.getArgOperand(0)).getValueType(), + getValue(I.getArgOperand(0)), + getValue(I.getArgOperand(1)))); + return; + case Intrinsic::minimum: + setValue(&I, DAG.getNode(ISD::FMINIMUM, sdl, + getValue(I.getArgOperand(0)).getValueType(), + getValue(I.getArgOperand(0)), + getValue(I.getArgOperand(1)))); + return; + case Intrinsic::maximum: + setValue(&I, DAG.getNode(ISD::FMAXIMUM, sdl, + getValue(I.getArgOperand(0)).getValueType(), + getValue(I.getArgOperand(0)), + getValue(I.getArgOperand(1)))); + return; + case Intrinsic::copysign: + setValue(&I, DAG.getNode(ISD::FCOPYSIGN, sdl, + getValue(I.getArgOperand(0)).getValueType(), + getValue(I.getArgOperand(0)), + getValue(I.getArgOperand(1)))); + return; + case Intrinsic::fma: + setValue(&I, DAG.getNode(ISD::FMA, sdl, + getValue(I.getArgOperand(0)).getValueType(), + getValue(I.getArgOperand(0)), + getValue(I.getArgOperand(1)), + getValue(I.getArgOperand(2)))); + return; +#define INSTRUCTION(NAME, NARG, ROUND_MODE, INTRINSIC, DAGN) \ + case Intrinsic::INTRINSIC: +#include "llvm/IR/ConstrainedOps.def" + visitConstrainedFPIntrinsic(cast<ConstrainedFPIntrinsic>(I)); + return; + case Intrinsic::fmuladd: { + EVT VT = TLI.getValueType(DAG.getDataLayout(), I.getType()); + if (TM.Options.AllowFPOpFusion != FPOpFusion::Strict && + TLI.isFMAFasterThanFMulAndFAdd(DAG.getMachineFunction(), VT)) { + setValue(&I, DAG.getNode(ISD::FMA, sdl, + getValue(I.getArgOperand(0)).getValueType(), + getValue(I.getArgOperand(0)), + getValue(I.getArgOperand(1)), + getValue(I.getArgOperand(2)))); + } else { + // TODO: Intrinsic calls should have fast-math-flags. + SDValue Mul = DAG.getNode(ISD::FMUL, sdl, + getValue(I.getArgOperand(0)).getValueType(), + getValue(I.getArgOperand(0)), + getValue(I.getArgOperand(1))); + SDValue Add = DAG.getNode(ISD::FADD, sdl, + getValue(I.getArgOperand(0)).getValueType(), + Mul, + getValue(I.getArgOperand(2))); + setValue(&I, Add); + } + return; + } + case Intrinsic::convert_to_fp16: + setValue(&I, DAG.getNode(ISD::BITCAST, sdl, MVT::i16, + DAG.getNode(ISD::FP_ROUND, sdl, MVT::f16, + getValue(I.getArgOperand(0)), + DAG.getTargetConstant(0, sdl, + MVT::i32)))); + return; + case Intrinsic::convert_from_fp16: + setValue(&I, DAG.getNode(ISD::FP_EXTEND, sdl, + TLI.getValueType(DAG.getDataLayout(), I.getType()), + DAG.getNode(ISD::BITCAST, sdl, MVT::f16, + getValue(I.getArgOperand(0))))); + return; + case Intrinsic::pcmarker: { + SDValue Tmp = getValue(I.getArgOperand(0)); + DAG.setRoot(DAG.getNode(ISD::PCMARKER, sdl, MVT::Other, getRoot(), Tmp)); + return; + } + case Intrinsic::readcyclecounter: { + SDValue Op = getRoot(); + Res = DAG.getNode(ISD::READCYCLECOUNTER, sdl, + DAG.getVTList(MVT::i64, MVT::Other), Op); + setValue(&I, Res); + DAG.setRoot(Res.getValue(1)); + return; + } + case Intrinsic::bitreverse: + setValue(&I, DAG.getNode(ISD::BITREVERSE, sdl, + getValue(I.getArgOperand(0)).getValueType(), + getValue(I.getArgOperand(0)))); + return; + case Intrinsic::bswap: + setValue(&I, DAG.getNode(ISD::BSWAP, sdl, + getValue(I.getArgOperand(0)).getValueType(), + getValue(I.getArgOperand(0)))); + return; + case Intrinsic::cttz: { + SDValue Arg = getValue(I.getArgOperand(0)); + ConstantInt *CI = cast<ConstantInt>(I.getArgOperand(1)); + EVT Ty = Arg.getValueType(); + setValue(&I, DAG.getNode(CI->isZero() ? ISD::CTTZ : ISD::CTTZ_ZERO_UNDEF, + sdl, Ty, Arg)); + return; + } + case Intrinsic::ctlz: { + SDValue Arg = getValue(I.getArgOperand(0)); + ConstantInt *CI = cast<ConstantInt>(I.getArgOperand(1)); + EVT Ty = Arg.getValueType(); + setValue(&I, DAG.getNode(CI->isZero() ? ISD::CTLZ : ISD::CTLZ_ZERO_UNDEF, + sdl, Ty, Arg)); + return; + } + case Intrinsic::ctpop: { + SDValue Arg = getValue(I.getArgOperand(0)); + EVT Ty = Arg.getValueType(); + setValue(&I, DAG.getNode(ISD::CTPOP, sdl, Ty, Arg)); + return; + } + case Intrinsic::fshl: + case Intrinsic::fshr: { + bool IsFSHL = Intrinsic == Intrinsic::fshl; + SDValue X = getValue(I.getArgOperand(0)); + SDValue Y = getValue(I.getArgOperand(1)); + SDValue Z = getValue(I.getArgOperand(2)); + EVT VT = X.getValueType(); + SDValue BitWidthC = DAG.getConstant(VT.getScalarSizeInBits(), sdl, VT); + SDValue Zero = DAG.getConstant(0, sdl, VT); + SDValue ShAmt = DAG.getNode(ISD::UREM, sdl, VT, Z, BitWidthC); + + auto FunnelOpcode = IsFSHL ? ISD::FSHL : ISD::FSHR; + if (TLI.isOperationLegalOrCustom(FunnelOpcode, VT)) { + setValue(&I, DAG.getNode(FunnelOpcode, sdl, VT, X, Y, Z)); + return; + } + + // When X == Y, this is rotate. If the data type has a power-of-2 size, we + // avoid the select that is necessary in the general case to filter out + // the 0-shift possibility that leads to UB. + if (X == Y && isPowerOf2_32(VT.getScalarSizeInBits())) { + auto RotateOpcode = IsFSHL ? ISD::ROTL : ISD::ROTR; + if (TLI.isOperationLegalOrCustom(RotateOpcode, VT)) { + setValue(&I, DAG.getNode(RotateOpcode, sdl, VT, X, Z)); + return; + } + + // Some targets only rotate one way. Try the opposite direction. + RotateOpcode = IsFSHL ? ISD::ROTR : ISD::ROTL; + if (TLI.isOperationLegalOrCustom(RotateOpcode, VT)) { + // Negate the shift amount because it is safe to ignore the high bits. + SDValue NegShAmt = DAG.getNode(ISD::SUB, sdl, VT, Zero, Z); + setValue(&I, DAG.getNode(RotateOpcode, sdl, VT, X, NegShAmt)); + return; + } + + // fshl (rotl): (X << (Z % BW)) | (X >> ((0 - Z) % BW)) + // fshr (rotr): (X << ((0 - Z) % BW)) | (X >> (Z % BW)) + SDValue NegZ = DAG.getNode(ISD::SUB, sdl, VT, Zero, Z); + SDValue NShAmt = DAG.getNode(ISD::UREM, sdl, VT, NegZ, BitWidthC); + SDValue ShX = DAG.getNode(ISD::SHL, sdl, VT, X, IsFSHL ? ShAmt : NShAmt); + SDValue ShY = DAG.getNode(ISD::SRL, sdl, VT, X, IsFSHL ? NShAmt : ShAmt); + setValue(&I, DAG.getNode(ISD::OR, sdl, VT, ShX, ShY)); + return; + } + + // fshl: (X << (Z % BW)) | (Y >> (BW - (Z % BW))) + // fshr: (X << (BW - (Z % BW))) | (Y >> (Z % BW)) + SDValue InvShAmt = DAG.getNode(ISD::SUB, sdl, VT, BitWidthC, ShAmt); + SDValue ShX = DAG.getNode(ISD::SHL, sdl, VT, X, IsFSHL ? ShAmt : InvShAmt); + SDValue ShY = DAG.getNode(ISD::SRL, sdl, VT, Y, IsFSHL ? InvShAmt : ShAmt); + SDValue Or = DAG.getNode(ISD::OR, sdl, VT, ShX, ShY); + + // If (Z % BW == 0), then the opposite direction shift is shift-by-bitwidth, + // and that is undefined. We must compare and select to avoid UB. + EVT CCVT = MVT::i1; + if (VT.isVector()) + CCVT = EVT::getVectorVT(*Context, CCVT, VT.getVectorNumElements()); + + // For fshl, 0-shift returns the 1st arg (X). + // For fshr, 0-shift returns the 2nd arg (Y). + SDValue IsZeroShift = DAG.getSetCC(sdl, CCVT, ShAmt, Zero, ISD::SETEQ); + setValue(&I, DAG.getSelect(sdl, VT, IsZeroShift, IsFSHL ? X : Y, Or)); + return; + } + case Intrinsic::sadd_sat: { + SDValue Op1 = getValue(I.getArgOperand(0)); + SDValue Op2 = getValue(I.getArgOperand(1)); + setValue(&I, DAG.getNode(ISD::SADDSAT, sdl, Op1.getValueType(), Op1, Op2)); + return; + } + case Intrinsic::uadd_sat: { + SDValue Op1 = getValue(I.getArgOperand(0)); + SDValue Op2 = getValue(I.getArgOperand(1)); + setValue(&I, DAG.getNode(ISD::UADDSAT, sdl, Op1.getValueType(), Op1, Op2)); + return; + } + case Intrinsic::ssub_sat: { + SDValue Op1 = getValue(I.getArgOperand(0)); + SDValue Op2 = getValue(I.getArgOperand(1)); + setValue(&I, DAG.getNode(ISD::SSUBSAT, sdl, Op1.getValueType(), Op1, Op2)); + return; + } + case Intrinsic::usub_sat: { + SDValue Op1 = getValue(I.getArgOperand(0)); + SDValue Op2 = getValue(I.getArgOperand(1)); + setValue(&I, DAG.getNode(ISD::USUBSAT, sdl, Op1.getValueType(), Op1, Op2)); + return; + } + case Intrinsic::smul_fix: + case Intrinsic::umul_fix: + case Intrinsic::smul_fix_sat: + case Intrinsic::umul_fix_sat: { + SDValue Op1 = getValue(I.getArgOperand(0)); + SDValue Op2 = getValue(I.getArgOperand(1)); + SDValue Op3 = getValue(I.getArgOperand(2)); + setValue(&I, DAG.getNode(FixedPointIntrinsicToOpcode(Intrinsic), sdl, + Op1.getValueType(), Op1, Op2, Op3)); + return; + } + case Intrinsic::sdiv_fix: + case Intrinsic::udiv_fix: { + SDValue Op1 = getValue(I.getArgOperand(0)); + SDValue Op2 = getValue(I.getArgOperand(1)); + SDValue Op3 = getValue(I.getArgOperand(2)); + setValue(&I, expandDivFix(FixedPointIntrinsicToOpcode(Intrinsic), sdl, + Op1, Op2, Op3, DAG, TLI)); + return; + } + case Intrinsic::stacksave: { + SDValue Op = getRoot(); + Res = DAG.getNode( + ISD::STACKSAVE, sdl, + DAG.getVTList(TLI.getPointerTy(DAG.getDataLayout()), MVT::Other), Op); + setValue(&I, Res); + DAG.setRoot(Res.getValue(1)); + return; + } + case Intrinsic::stackrestore: + Res = getValue(I.getArgOperand(0)); + DAG.setRoot(DAG.getNode(ISD::STACKRESTORE, sdl, MVT::Other, getRoot(), Res)); + return; + case Intrinsic::get_dynamic_area_offset: { + SDValue Op = getRoot(); + EVT PtrTy = TLI.getPointerTy(DAG.getDataLayout()); + EVT ResTy = TLI.getValueType(DAG.getDataLayout(), I.getType()); + // Result type for @llvm.get.dynamic.area.offset should match PtrTy for + // target. + if (PtrTy.getSizeInBits() < ResTy.getSizeInBits()) + report_fatal_error("Wrong result type for @llvm.get.dynamic.area.offset" + " intrinsic!"); + Res = DAG.getNode(ISD::GET_DYNAMIC_AREA_OFFSET, sdl, DAG.getVTList(ResTy), + Op); + DAG.setRoot(Op); + setValue(&I, Res); + return; + } + case Intrinsic::stackguard: { + EVT PtrTy = TLI.getPointerTy(DAG.getDataLayout()); + MachineFunction &MF = DAG.getMachineFunction(); + const Module &M = *MF.getFunction().getParent(); + SDValue Chain = getRoot(); + if (TLI.useLoadStackGuardNode()) { + Res = getLoadStackGuard(DAG, sdl, Chain); + } else { + const Value *Global = TLI.getSDagStackGuard(M); + unsigned Align = DL->getPrefTypeAlignment(Global->getType()); + Res = DAG.getLoad(PtrTy, sdl, Chain, getValue(Global), + MachinePointerInfo(Global, 0), Align, + MachineMemOperand::MOVolatile); + } + if (TLI.useStackGuardXorFP()) + Res = TLI.emitStackGuardXorFP(DAG, Res, sdl); + DAG.setRoot(Chain); + setValue(&I, Res); + return; + } + case Intrinsic::stackprotector: { + // Emit code into the DAG to store the stack guard onto the stack. + MachineFunction &MF = DAG.getMachineFunction(); + MachineFrameInfo &MFI = MF.getFrameInfo(); + EVT PtrTy = TLI.getPointerTy(DAG.getDataLayout()); + SDValue Src, Chain = getRoot(); + + if (TLI.useLoadStackGuardNode()) + Src = getLoadStackGuard(DAG, sdl, Chain); + else + Src = getValue(I.getArgOperand(0)); // The guard's value. + + AllocaInst *Slot = cast<AllocaInst>(I.getArgOperand(1)); + + int FI = FuncInfo.StaticAllocaMap[Slot]; + MFI.setStackProtectorIndex(FI); + + SDValue FIN = DAG.getFrameIndex(FI, PtrTy); + + // Store the stack protector onto the stack. + Res = DAG.getStore(Chain, sdl, Src, FIN, MachinePointerInfo::getFixedStack( + DAG.getMachineFunction(), FI), + /* Alignment = */ 0, MachineMemOperand::MOVolatile); + setValue(&I, Res); + DAG.setRoot(Res); + return; + } + case Intrinsic::objectsize: + llvm_unreachable("llvm.objectsize.* should have been lowered already"); + + case Intrinsic::is_constant: + llvm_unreachable("llvm.is.constant.* should have been lowered already"); + + case Intrinsic::annotation: + case Intrinsic::ptr_annotation: + case Intrinsic::launder_invariant_group: + case Intrinsic::strip_invariant_group: + // Drop the intrinsic, but forward the value + setValue(&I, getValue(I.getOperand(0))); + return; + case Intrinsic::assume: + case Intrinsic::var_annotation: + case Intrinsic::sideeffect: + // Discard annotate attributes, assumptions, and artificial side-effects. + return; + + case Intrinsic::codeview_annotation: { + // Emit a label associated with this metadata. + MachineFunction &MF = DAG.getMachineFunction(); + MCSymbol *Label = + MF.getMMI().getContext().createTempSymbol("annotation", true); + Metadata *MD = cast<MetadataAsValue>(I.getArgOperand(0))->getMetadata(); + MF.addCodeViewAnnotation(Label, cast<MDNode>(MD)); + Res = DAG.getLabelNode(ISD::ANNOTATION_LABEL, sdl, getRoot(), Label); + DAG.setRoot(Res); + return; + } + + case Intrinsic::init_trampoline: { + const Function *F = cast<Function>(I.getArgOperand(1)->stripPointerCasts()); + + SDValue Ops[6]; + Ops[0] = getRoot(); + Ops[1] = getValue(I.getArgOperand(0)); + Ops[2] = getValue(I.getArgOperand(1)); + Ops[3] = getValue(I.getArgOperand(2)); + Ops[4] = DAG.getSrcValue(I.getArgOperand(0)); + Ops[5] = DAG.getSrcValue(F); + + Res = DAG.getNode(ISD::INIT_TRAMPOLINE, sdl, MVT::Other, Ops); + + DAG.setRoot(Res); + return; + } + case Intrinsic::adjust_trampoline: + setValue(&I, DAG.getNode(ISD::ADJUST_TRAMPOLINE, sdl, + TLI.getPointerTy(DAG.getDataLayout()), + getValue(I.getArgOperand(0)))); + return; + case Intrinsic::gcroot: { + assert(DAG.getMachineFunction().getFunction().hasGC() && + "only valid in functions with gc specified, enforced by Verifier"); + assert(GFI && "implied by previous"); + const Value *Alloca = I.getArgOperand(0)->stripPointerCasts(); + const Constant *TypeMap = cast<Constant>(I.getArgOperand(1)); + + FrameIndexSDNode *FI = cast<FrameIndexSDNode>(getValue(Alloca).getNode()); + GFI->addStackRoot(FI->getIndex(), TypeMap); + return; + } + case Intrinsic::gcread: + case Intrinsic::gcwrite: + llvm_unreachable("GC failed to lower gcread/gcwrite intrinsics!"); + case Intrinsic::flt_rounds: + setValue(&I, DAG.getNode(ISD::FLT_ROUNDS_, sdl, MVT::i32)); + return; + + case Intrinsic::expect: + // Just replace __builtin_expect(exp, c) with EXP. + setValue(&I, getValue(I.getArgOperand(0))); + return; + + case Intrinsic::debugtrap: + case Intrinsic::trap: { + StringRef TrapFuncName = + I.getAttributes() + .getAttribute(AttributeList::FunctionIndex, "trap-func-name") + .getValueAsString(); + if (TrapFuncName.empty()) { + ISD::NodeType Op = (Intrinsic == Intrinsic::trap) ? + ISD::TRAP : ISD::DEBUGTRAP; + DAG.setRoot(DAG.getNode(Op, sdl,MVT::Other, getRoot())); + return; + } + TargetLowering::ArgListTy Args; + + TargetLowering::CallLoweringInfo CLI(DAG); + CLI.setDebugLoc(sdl).setChain(getRoot()).setLibCallee( + CallingConv::C, I.getType(), + DAG.getExternalSymbol(TrapFuncName.data(), + TLI.getPointerTy(DAG.getDataLayout())), + std::move(Args)); + + std::pair<SDValue, SDValue> Result = TLI.LowerCallTo(CLI); + DAG.setRoot(Result.second); + return; + } + + case Intrinsic::uadd_with_overflow: + case Intrinsic::sadd_with_overflow: + case Intrinsic::usub_with_overflow: + case Intrinsic::ssub_with_overflow: + case Intrinsic::umul_with_overflow: + case Intrinsic::smul_with_overflow: { + ISD::NodeType Op; + switch (Intrinsic) { + default: llvm_unreachable("Impossible intrinsic"); // Can't reach here. + case Intrinsic::uadd_with_overflow: Op = ISD::UADDO; break; + case Intrinsic::sadd_with_overflow: Op = ISD::SADDO; break; + case Intrinsic::usub_with_overflow: Op = ISD::USUBO; break; + case Intrinsic::ssub_with_overflow: Op = ISD::SSUBO; break; + case Intrinsic::umul_with_overflow: Op = ISD::UMULO; break; + case Intrinsic::smul_with_overflow: Op = ISD::SMULO; break; + } + SDValue Op1 = getValue(I.getArgOperand(0)); + SDValue Op2 = getValue(I.getArgOperand(1)); + + EVT ResultVT = Op1.getValueType(); + EVT OverflowVT = MVT::i1; + if (ResultVT.isVector()) + OverflowVT = EVT::getVectorVT( + *Context, OverflowVT, ResultVT.getVectorNumElements()); + + SDVTList VTs = DAG.getVTList(ResultVT, OverflowVT); + setValue(&I, DAG.getNode(Op, sdl, VTs, Op1, Op2)); + return; + } + case Intrinsic::prefetch: { + SDValue Ops[5]; + unsigned rw = cast<ConstantInt>(I.getArgOperand(1))->getZExtValue(); + auto Flags = rw == 0 ? MachineMemOperand::MOLoad :MachineMemOperand::MOStore; + Ops[0] = DAG.getRoot(); + Ops[1] = getValue(I.getArgOperand(0)); + Ops[2] = getValue(I.getArgOperand(1)); + Ops[3] = getValue(I.getArgOperand(2)); + Ops[4] = getValue(I.getArgOperand(3)); + SDValue Result = DAG.getMemIntrinsicNode(ISD::PREFETCH, sdl, + DAG.getVTList(MVT::Other), Ops, + EVT::getIntegerVT(*Context, 8), + MachinePointerInfo(I.getArgOperand(0)), + 0, /* align */ + Flags); + + // Chain the prefetch in parallell with any pending loads, to stay out of + // the way of later optimizations. + PendingLoads.push_back(Result); + Result = getRoot(); + DAG.setRoot(Result); + return; + } + case Intrinsic::lifetime_start: + case Intrinsic::lifetime_end: { + bool IsStart = (Intrinsic == Intrinsic::lifetime_start); + // Stack coloring is not enabled in O0, discard region information. + if (TM.getOptLevel() == CodeGenOpt::None) + return; + + const int64_t ObjectSize = + cast<ConstantInt>(I.getArgOperand(0))->getSExtValue(); + Value *const ObjectPtr = I.getArgOperand(1); + SmallVector<const Value *, 4> Allocas; + GetUnderlyingObjects(ObjectPtr, Allocas, *DL); + + for (SmallVectorImpl<const Value*>::iterator Object = Allocas.begin(), + E = Allocas.end(); Object != E; ++Object) { + const AllocaInst *LifetimeObject = dyn_cast_or_null<AllocaInst>(*Object); + + // Could not find an Alloca. + if (!LifetimeObject) + continue; + + // First check that the Alloca is static, otherwise it won't have a + // valid frame index. + auto SI = FuncInfo.StaticAllocaMap.find(LifetimeObject); + if (SI == FuncInfo.StaticAllocaMap.end()) + return; + + const int FrameIndex = SI->second; + int64_t Offset; + if (GetPointerBaseWithConstantOffset( + ObjectPtr, Offset, DAG.getDataLayout()) != LifetimeObject) + Offset = -1; // Cannot determine offset from alloca to lifetime object. + Res = DAG.getLifetimeNode(IsStart, sdl, getRoot(), FrameIndex, ObjectSize, + Offset); + DAG.setRoot(Res); + } + return; + } + case Intrinsic::invariant_start: + // Discard region information. + setValue(&I, DAG.getUNDEF(TLI.getPointerTy(DAG.getDataLayout()))); + return; + case Intrinsic::invariant_end: + // Discard region information. + return; + case Intrinsic::clear_cache: + /// FunctionName may be null. + if (const char *FunctionName = TLI.getClearCacheBuiltinName()) + lowerCallToExternalSymbol(I, FunctionName); + return; + case Intrinsic::donothing: + // ignore + return; + case Intrinsic::experimental_stackmap: + visitStackmap(I); + return; + case Intrinsic::experimental_patchpoint_void: + case Intrinsic::experimental_patchpoint_i64: + visitPatchpoint(&I); + return; + case Intrinsic::experimental_gc_statepoint: + LowerStatepoint(ImmutableStatepoint(&I)); + return; + case Intrinsic::experimental_gc_result: + visitGCResult(cast<GCResultInst>(I)); + return; + case Intrinsic::experimental_gc_relocate: + visitGCRelocate(cast<GCRelocateInst>(I)); + return; + case Intrinsic::instrprof_increment: + llvm_unreachable("instrprof failed to lower an increment"); + case Intrinsic::instrprof_value_profile: + llvm_unreachable("instrprof failed to lower a value profiling call"); + case Intrinsic::localescape: { + MachineFunction &MF = DAG.getMachineFunction(); + const TargetInstrInfo *TII = DAG.getSubtarget().getInstrInfo(); + + // Directly emit some LOCAL_ESCAPE machine instrs. Label assignment emission + // is the same on all targets. + for (unsigned Idx = 0, E = I.getNumArgOperands(); Idx < E; ++Idx) { + Value *Arg = I.getArgOperand(Idx)->stripPointerCasts(); + if (isa<ConstantPointerNull>(Arg)) + continue; // Skip null pointers. They represent a hole in index space. + AllocaInst *Slot = cast<AllocaInst>(Arg); + assert(FuncInfo.StaticAllocaMap.count(Slot) && + "can only escape static allocas"); + int FI = FuncInfo.StaticAllocaMap[Slot]; + MCSymbol *FrameAllocSym = + MF.getMMI().getContext().getOrCreateFrameAllocSymbol( + GlobalValue::dropLLVMManglingEscape(MF.getName()), Idx); + BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, dl, + TII->get(TargetOpcode::LOCAL_ESCAPE)) + .addSym(FrameAllocSym) + .addFrameIndex(FI); + } + + return; + } + + case Intrinsic::localrecover: { + // i8* @llvm.localrecover(i8* %fn, i8* %fp, i32 %idx) + MachineFunction &MF = DAG.getMachineFunction(); + MVT PtrVT = TLI.getPointerTy(DAG.getDataLayout(), 0); + + // Get the symbol that defines the frame offset. + auto *Fn = cast<Function>(I.getArgOperand(0)->stripPointerCasts()); + auto *Idx = cast<ConstantInt>(I.getArgOperand(2)); + unsigned IdxVal = + unsigned(Idx->getLimitedValue(std::numeric_limits<int>::max())); + MCSymbol *FrameAllocSym = + MF.getMMI().getContext().getOrCreateFrameAllocSymbol( + GlobalValue::dropLLVMManglingEscape(Fn->getName()), IdxVal); + + // Create a MCSymbol for the label to avoid any target lowering + // that would make this PC relative. + SDValue OffsetSym = DAG.getMCSymbol(FrameAllocSym, PtrVT); + SDValue OffsetVal = + DAG.getNode(ISD::LOCAL_RECOVER, sdl, PtrVT, OffsetSym); + + // Add the offset to the FP. + Value *FP = I.getArgOperand(1); + SDValue FPVal = getValue(FP); + SDValue Add = DAG.getMemBasePlusOffset(FPVal, OffsetVal, sdl); + setValue(&I, Add); + + return; + } + + case Intrinsic::eh_exceptionpointer: + case Intrinsic::eh_exceptioncode: { + // Get the exception pointer vreg, copy from it, and resize it to fit. + const auto *CPI = cast<CatchPadInst>(I.getArgOperand(0)); + MVT PtrVT = TLI.getPointerTy(DAG.getDataLayout()); + const TargetRegisterClass *PtrRC = TLI.getRegClassFor(PtrVT); + unsigned VReg = FuncInfo.getCatchPadExceptionPointerVReg(CPI, PtrRC); + SDValue N = + DAG.getCopyFromReg(DAG.getEntryNode(), getCurSDLoc(), VReg, PtrVT); + if (Intrinsic == Intrinsic::eh_exceptioncode) + N = DAG.getZExtOrTrunc(N, getCurSDLoc(), MVT::i32); + setValue(&I, N); + return; + } + case Intrinsic::xray_customevent: { + // Here we want to make sure that the intrinsic behaves as if it has a + // specific calling convention, and only for x86_64. + // FIXME: Support other platforms later. + const auto &Triple = DAG.getTarget().getTargetTriple(); + if (Triple.getArch() != Triple::x86_64 || !Triple.isOSLinux()) + return; + + SDLoc DL = getCurSDLoc(); + SmallVector<SDValue, 8> Ops; + + // We want to say that we always want the arguments in registers. + SDValue LogEntryVal = getValue(I.getArgOperand(0)); + SDValue StrSizeVal = getValue(I.getArgOperand(1)); + SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Glue); + SDValue Chain = getRoot(); + Ops.push_back(LogEntryVal); + Ops.push_back(StrSizeVal); + Ops.push_back(Chain); + + // We need to enforce the calling convention for the callsite, so that + // argument ordering is enforced correctly, and that register allocation can + // see that some registers may be assumed clobbered and have to preserve + // them across calls to the intrinsic. + MachineSDNode *MN = DAG.getMachineNode(TargetOpcode::PATCHABLE_EVENT_CALL, + DL, NodeTys, Ops); + SDValue patchableNode = SDValue(MN, 0); + DAG.setRoot(patchableNode); + setValue(&I, patchableNode); + return; + } + case Intrinsic::xray_typedevent: { + // Here we want to make sure that the intrinsic behaves as if it has a + // specific calling convention, and only for x86_64. + // FIXME: Support other platforms later. + const auto &Triple = DAG.getTarget().getTargetTriple(); + if (Triple.getArch() != Triple::x86_64 || !Triple.isOSLinux()) + return; + + SDLoc DL = getCurSDLoc(); + SmallVector<SDValue, 8> Ops; + + // We want to say that we always want the arguments in registers. + // It's unclear to me how manipulating the selection DAG here forces callers + // to provide arguments in registers instead of on the stack. + SDValue LogTypeId = getValue(I.getArgOperand(0)); + SDValue LogEntryVal = getValue(I.getArgOperand(1)); + SDValue StrSizeVal = getValue(I.getArgOperand(2)); + SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Glue); + SDValue Chain = getRoot(); + Ops.push_back(LogTypeId); + Ops.push_back(LogEntryVal); + Ops.push_back(StrSizeVal); + Ops.push_back(Chain); + + // We need to enforce the calling convention for the callsite, so that + // argument ordering is enforced correctly, and that register allocation can + // see that some registers may be assumed clobbered and have to preserve + // them across calls to the intrinsic. + MachineSDNode *MN = DAG.getMachineNode( + TargetOpcode::PATCHABLE_TYPED_EVENT_CALL, DL, NodeTys, Ops); + SDValue patchableNode = SDValue(MN, 0); + DAG.setRoot(patchableNode); + setValue(&I, patchableNode); + return; + } + case Intrinsic::experimental_deoptimize: + LowerDeoptimizeCall(&I); + return; + + case Intrinsic::experimental_vector_reduce_v2_fadd: + case Intrinsic::experimental_vector_reduce_v2_fmul: + case Intrinsic::experimental_vector_reduce_add: + case Intrinsic::experimental_vector_reduce_mul: + case Intrinsic::experimental_vector_reduce_and: + case Intrinsic::experimental_vector_reduce_or: + case Intrinsic::experimental_vector_reduce_xor: + case Intrinsic::experimental_vector_reduce_smax: + case Intrinsic::experimental_vector_reduce_smin: + case Intrinsic::experimental_vector_reduce_umax: + case Intrinsic::experimental_vector_reduce_umin: + case Intrinsic::experimental_vector_reduce_fmax: + case Intrinsic::experimental_vector_reduce_fmin: + visitVectorReduce(I, Intrinsic); + return; + + case Intrinsic::icall_branch_funnel: { + SmallVector<SDValue, 16> Ops; + Ops.push_back(getValue(I.getArgOperand(0))); + + int64_t Offset; + auto *Base = dyn_cast<GlobalObject>(GetPointerBaseWithConstantOffset( + I.getArgOperand(1), Offset, DAG.getDataLayout())); + if (!Base) + report_fatal_error( + "llvm.icall.branch.funnel operand must be a GlobalValue"); + Ops.push_back(DAG.getTargetGlobalAddress(Base, getCurSDLoc(), MVT::i64, 0)); + + struct BranchFunnelTarget { + int64_t Offset; + SDValue Target; + }; + SmallVector<BranchFunnelTarget, 8> Targets; + + for (unsigned Op = 1, N = I.getNumArgOperands(); Op != N; Op += 2) { + auto *ElemBase = dyn_cast<GlobalObject>(GetPointerBaseWithConstantOffset( + I.getArgOperand(Op), Offset, DAG.getDataLayout())); + if (ElemBase != Base) + report_fatal_error("all llvm.icall.branch.funnel operands must refer " + "to the same GlobalValue"); + + SDValue Val = getValue(I.getArgOperand(Op + 1)); + auto *GA = dyn_cast<GlobalAddressSDNode>(Val); + if (!GA) + report_fatal_error( + "llvm.icall.branch.funnel operand must be a GlobalValue"); + Targets.push_back({Offset, DAG.getTargetGlobalAddress( + GA->getGlobal(), getCurSDLoc(), + Val.getValueType(), GA->getOffset())}); + } + llvm::sort(Targets, + [](const BranchFunnelTarget &T1, const BranchFunnelTarget &T2) { + return T1.Offset < T2.Offset; + }); + + for (auto &T : Targets) { + Ops.push_back(DAG.getTargetConstant(T.Offset, getCurSDLoc(), MVT::i32)); + Ops.push_back(T.Target); + } + + Ops.push_back(DAG.getRoot()); // Chain + SDValue N(DAG.getMachineNode(TargetOpcode::ICALL_BRANCH_FUNNEL, + getCurSDLoc(), MVT::Other, Ops), + 0); + DAG.setRoot(N); + setValue(&I, N); + HasTailCall = true; + return; + } + + case Intrinsic::wasm_landingpad_index: + // Information this intrinsic contained has been transferred to + // MachineFunction in SelectionDAGISel::PrepareEHLandingPad. We can safely + // delete it now. + return; + + case Intrinsic::aarch64_settag: + case Intrinsic::aarch64_settag_zero: { + const SelectionDAGTargetInfo &TSI = DAG.getSelectionDAGInfo(); + bool ZeroMemory = Intrinsic == Intrinsic::aarch64_settag_zero; + SDValue Val = TSI.EmitTargetCodeForSetTag( + DAG, getCurSDLoc(), getRoot(), getValue(I.getArgOperand(0)), + getValue(I.getArgOperand(1)), MachinePointerInfo(I.getArgOperand(0)), + ZeroMemory); + DAG.setRoot(Val); + setValue(&I, Val); + return; + } + case Intrinsic::ptrmask: { + SDValue Ptr = getValue(I.getOperand(0)); + SDValue Const = getValue(I.getOperand(1)); + + EVT DestVT = + EVT(DAG.getTargetLoweringInfo().getPointerTy(DAG.getDataLayout())); + + setValue(&I, DAG.getNode(ISD::AND, getCurSDLoc(), DestVT, Ptr, + DAG.getZExtOrTrunc(Const, getCurSDLoc(), DestVT))); + return; + } + } +} + +void SelectionDAGBuilder::visitConstrainedFPIntrinsic( + const ConstrainedFPIntrinsic &FPI) { + SDLoc sdl = getCurSDLoc(); + + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + SmallVector<EVT, 4> ValueVTs; + ComputeValueVTs(TLI, DAG.getDataLayout(), FPI.getType(), ValueVTs); + ValueVTs.push_back(MVT::Other); // Out chain + + // We do not need to serialize constrained FP intrinsics against + // each other or against (nonvolatile) loads, so they can be + // chained like loads. + SDValue Chain = DAG.getRoot(); + SmallVector<SDValue, 4> Opers; + Opers.push_back(Chain); + if (FPI.isUnaryOp()) { + Opers.push_back(getValue(FPI.getArgOperand(0))); + } else if (FPI.isTernaryOp()) { + Opers.push_back(getValue(FPI.getArgOperand(0))); + Opers.push_back(getValue(FPI.getArgOperand(1))); + Opers.push_back(getValue(FPI.getArgOperand(2))); + } else { + Opers.push_back(getValue(FPI.getArgOperand(0))); + Opers.push_back(getValue(FPI.getArgOperand(1))); + } + + unsigned Opcode; + switch (FPI.getIntrinsicID()) { + default: llvm_unreachable("Impossible intrinsic"); // Can't reach here. +#define INSTRUCTION(NAME, NARG, ROUND_MODE, INTRINSIC, DAGN) \ + case Intrinsic::INTRINSIC: \ + Opcode = ISD::STRICT_##DAGN; \ + break; +#include "llvm/IR/ConstrainedOps.def" + } + + // A few strict DAG nodes carry additional operands that are not + // set up by the default code above. + switch (Opcode) { + default: break; + case ISD::STRICT_FP_ROUND: + Opers.push_back( + DAG.getTargetConstant(0, sdl, TLI.getPointerTy(DAG.getDataLayout()))); + break; + case ISD::STRICT_FSETCC: + case ISD::STRICT_FSETCCS: { + auto *FPCmp = dyn_cast<ConstrainedFPCmpIntrinsic>(&FPI); + Opers.push_back(DAG.getCondCode(getFCmpCondCode(FPCmp->getPredicate()))); + break; + } + } + + SDVTList VTs = DAG.getVTList(ValueVTs); + SDValue Result = DAG.getNode(Opcode, sdl, VTs, Opers); + + assert(Result.getNode()->getNumValues() == 2); + + // Push node to the appropriate list so that future instructions can be + // chained up correctly. + SDValue OutChain = Result.getValue(1); + switch (FPI.getExceptionBehavior().getValue()) { + case fp::ExceptionBehavior::ebIgnore: + // The only reason why ebIgnore nodes still need to be chained is that + // they might depend on the current rounding mode, and therefore must + // not be moved across instruction that may change that mode. + LLVM_FALLTHROUGH; + case fp::ExceptionBehavior::ebMayTrap: + // These must not be moved across calls or instructions that may change + // floating-point exception masks. + PendingConstrainedFP.push_back(OutChain); + break; + case fp::ExceptionBehavior::ebStrict: + // These must not be moved across calls or instructions that may change + // floating-point exception masks or read floating-point exception flags. + // In addition, they cannot be optimized out even if unused. + PendingConstrainedFPStrict.push_back(OutChain); + break; + } + + SDValue FPResult = Result.getValue(0); + setValue(&FPI, FPResult); +} + +std::pair<SDValue, SDValue> +SelectionDAGBuilder::lowerInvokable(TargetLowering::CallLoweringInfo &CLI, + const BasicBlock *EHPadBB) { + MachineFunction &MF = DAG.getMachineFunction(); + MachineModuleInfo &MMI = MF.getMMI(); + MCSymbol *BeginLabel = nullptr; + + if (EHPadBB) { + // Insert a label before the invoke call to mark the try range. This can be + // used to detect deletion of the invoke via the MachineModuleInfo. + BeginLabel = MMI.getContext().createTempSymbol(); + + // For SjLj, keep track of which landing pads go with which invokes + // so as to maintain the ordering of pads in the LSDA. + unsigned CallSiteIndex = MMI.getCurrentCallSite(); + if (CallSiteIndex) { + MF.setCallSiteBeginLabel(BeginLabel, CallSiteIndex); + LPadToCallSiteMap[FuncInfo.MBBMap[EHPadBB]].push_back(CallSiteIndex); + + // Now that the call site is handled, stop tracking it. + MMI.setCurrentCallSite(0); + } + + // Both PendingLoads and PendingExports must be flushed here; + // this call might not return. + (void)getRoot(); + DAG.setRoot(DAG.getEHLabel(getCurSDLoc(), getControlRoot(), BeginLabel)); + + CLI.setChain(getRoot()); + } + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + std::pair<SDValue, SDValue> Result = TLI.LowerCallTo(CLI); + + assert((CLI.IsTailCall || Result.second.getNode()) && + "Non-null chain expected with non-tail call!"); + assert((Result.second.getNode() || !Result.first.getNode()) && + "Null value expected with tail call!"); + + if (!Result.second.getNode()) { + // As a special case, a null chain means that a tail call has been emitted + // and the DAG root is already updated. + HasTailCall = true; + + // Since there's no actual continuation from this block, nothing can be + // relying on us setting vregs for them. + PendingExports.clear(); + } else { + DAG.setRoot(Result.second); + } + + if (EHPadBB) { + // Insert a label at the end of the invoke call to mark the try range. This + // can be used to detect deletion of the invoke via the MachineModuleInfo. + MCSymbol *EndLabel = MMI.getContext().createTempSymbol(); + DAG.setRoot(DAG.getEHLabel(getCurSDLoc(), getRoot(), EndLabel)); + + // Inform MachineModuleInfo of range. + auto Pers = classifyEHPersonality(FuncInfo.Fn->getPersonalityFn()); + // There is a platform (e.g. wasm) that uses funclet style IR but does not + // actually use outlined funclets and their LSDA info style. + if (MF.hasEHFunclets() && isFuncletEHPersonality(Pers)) { + assert(CLI.CS); + WinEHFuncInfo *EHInfo = DAG.getMachineFunction().getWinEHFuncInfo(); + EHInfo->addIPToStateRange(cast<InvokeInst>(CLI.CS.getInstruction()), + BeginLabel, EndLabel); + } else if (!isScopedEHPersonality(Pers)) { + MF.addInvoke(FuncInfo.MBBMap[EHPadBB], BeginLabel, EndLabel); + } + } + + return Result; +} + +void SelectionDAGBuilder::LowerCallTo(ImmutableCallSite CS, SDValue Callee, + bool isTailCall, + const BasicBlock *EHPadBB) { + auto &DL = DAG.getDataLayout(); + FunctionType *FTy = CS.getFunctionType(); + Type *RetTy = CS.getType(); + + TargetLowering::ArgListTy Args; + Args.reserve(CS.arg_size()); + + const Value *SwiftErrorVal = nullptr; + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + + if (isTailCall) { + // Avoid emitting tail calls in functions with the disable-tail-calls + // attribute. + auto *Caller = CS.getInstruction()->getParent()->getParent(); + if (Caller->getFnAttribute("disable-tail-calls").getValueAsString() == + "true") + isTailCall = false; + + // We can't tail call inside a function with a swifterror argument. Lowering + // does not support this yet. It would have to move into the swifterror + // register before the call. + if (TLI.supportSwiftError() && + Caller->getAttributes().hasAttrSomewhere(Attribute::SwiftError)) + isTailCall = false; + } + + for (ImmutableCallSite::arg_iterator i = CS.arg_begin(), e = CS.arg_end(); + i != e; ++i) { + TargetLowering::ArgListEntry Entry; + const Value *V = *i; + + // Skip empty types + if (V->getType()->isEmptyTy()) + continue; + + SDValue ArgNode = getValue(V); + Entry.Node = ArgNode; Entry.Ty = V->getType(); + + Entry.setAttributes(&CS, i - CS.arg_begin()); + + // Use swifterror virtual register as input to the call. + if (Entry.IsSwiftError && TLI.supportSwiftError()) { + SwiftErrorVal = V; + // We find the virtual register for the actual swifterror argument. + // Instead of using the Value, we use the virtual register instead. + Entry.Node = DAG.getRegister( + SwiftError.getOrCreateVRegUseAt(CS.getInstruction(), FuncInfo.MBB, V), + EVT(TLI.getPointerTy(DL))); + } + + Args.push_back(Entry); + + // If we have an explicit sret argument that is an Instruction, (i.e., it + // might point to function-local memory), we can't meaningfully tail-call. + if (Entry.IsSRet && isa<Instruction>(V)) + isTailCall = false; + } + + // If call site has a cfguardtarget operand bundle, create and add an + // additional ArgListEntry. + if (auto Bundle = CS.getOperandBundle(LLVMContext::OB_cfguardtarget)) { + TargetLowering::ArgListEntry Entry; + Value *V = Bundle->Inputs[0]; + SDValue ArgNode = getValue(V); + Entry.Node = ArgNode; + Entry.Ty = V->getType(); + Entry.IsCFGuardTarget = true; + Args.push_back(Entry); + } + + // Check if target-independent constraints permit a tail call here. + // Target-dependent constraints are checked within TLI->LowerCallTo. + if (isTailCall && !isInTailCallPosition(CS, DAG.getTarget())) + isTailCall = false; + + // Disable tail calls if there is an swifterror argument. Targets have not + // been updated to support tail calls. + if (TLI.supportSwiftError() && SwiftErrorVal) + isTailCall = false; + + TargetLowering::CallLoweringInfo CLI(DAG); + CLI.setDebugLoc(getCurSDLoc()) + .setChain(getRoot()) + .setCallee(RetTy, FTy, Callee, std::move(Args), CS) + .setTailCall(isTailCall) + .setConvergent(CS.isConvergent()); + std::pair<SDValue, SDValue> Result = lowerInvokable(CLI, EHPadBB); + + if (Result.first.getNode()) { + const Instruction *Inst = CS.getInstruction(); + Result.first = lowerRangeToAssertZExt(DAG, *Inst, Result.first); + setValue(Inst, Result.first); + } + + // The last element of CLI.InVals has the SDValue for swifterror return. + // Here we copy it to a virtual register and update SwiftErrorMap for + // book-keeping. + if (SwiftErrorVal && TLI.supportSwiftError()) { + // Get the last element of InVals. + SDValue Src = CLI.InVals.back(); + Register VReg = SwiftError.getOrCreateVRegDefAt( + CS.getInstruction(), FuncInfo.MBB, SwiftErrorVal); + SDValue CopyNode = CLI.DAG.getCopyToReg(Result.second, CLI.DL, VReg, Src); + DAG.setRoot(CopyNode); + } +} + +static SDValue getMemCmpLoad(const Value *PtrVal, MVT LoadVT, + SelectionDAGBuilder &Builder) { + // Check to see if this load can be trivially constant folded, e.g. if the + // input is from a string literal. + if (const Constant *LoadInput = dyn_cast<Constant>(PtrVal)) { + // Cast pointer to the type we really want to load. + Type *LoadTy = + Type::getIntNTy(PtrVal->getContext(), LoadVT.getScalarSizeInBits()); + if (LoadVT.isVector()) + LoadTy = VectorType::get(LoadTy, LoadVT.getVectorNumElements()); + + LoadInput = ConstantExpr::getBitCast(const_cast<Constant *>(LoadInput), + PointerType::getUnqual(LoadTy)); + + if (const Constant *LoadCst = ConstantFoldLoadFromConstPtr( + const_cast<Constant *>(LoadInput), LoadTy, *Builder.DL)) + return Builder.getValue(LoadCst); + } + + // Otherwise, we have to emit the load. If the pointer is to unfoldable but + // still constant memory, the input chain can be the entry node. + SDValue Root; + bool ConstantMemory = false; + + // Do not serialize (non-volatile) loads of constant memory with anything. + if (Builder.AA && Builder.AA->pointsToConstantMemory(PtrVal)) { + Root = Builder.DAG.getEntryNode(); + ConstantMemory = true; + } else { + // Do not serialize non-volatile loads against each other. + Root = Builder.DAG.getRoot(); + } + + SDValue Ptr = Builder.getValue(PtrVal); + SDValue LoadVal = Builder.DAG.getLoad(LoadVT, Builder.getCurSDLoc(), Root, + Ptr, MachinePointerInfo(PtrVal), + /* Alignment = */ 1); + + if (!ConstantMemory) + Builder.PendingLoads.push_back(LoadVal.getValue(1)); + return LoadVal; +} + +/// Record the value for an instruction that produces an integer result, +/// converting the type where necessary. +void SelectionDAGBuilder::processIntegerCallValue(const Instruction &I, + SDValue Value, + bool IsSigned) { + EVT VT = DAG.getTargetLoweringInfo().getValueType(DAG.getDataLayout(), + I.getType(), true); + if (IsSigned) + Value = DAG.getSExtOrTrunc(Value, getCurSDLoc(), VT); + else + Value = DAG.getZExtOrTrunc(Value, getCurSDLoc(), VT); + setValue(&I, Value); +} + +/// See if we can lower a memcmp call into an optimized form. If so, return +/// true and lower it. Otherwise return false, and it will be lowered like a +/// normal call. +/// The caller already checked that \p I calls the appropriate LibFunc with a +/// correct prototype. +bool SelectionDAGBuilder::visitMemCmpCall(const CallInst &I) { + const Value *LHS = I.getArgOperand(0), *RHS = I.getArgOperand(1); + const Value *Size = I.getArgOperand(2); + const ConstantInt *CSize = dyn_cast<ConstantInt>(Size); + if (CSize && CSize->getZExtValue() == 0) { + EVT CallVT = DAG.getTargetLoweringInfo().getValueType(DAG.getDataLayout(), + I.getType(), true); + setValue(&I, DAG.getConstant(0, getCurSDLoc(), CallVT)); + return true; + } + + const SelectionDAGTargetInfo &TSI = DAG.getSelectionDAGInfo(); + std::pair<SDValue, SDValue> Res = TSI.EmitTargetCodeForMemcmp( + DAG, getCurSDLoc(), DAG.getRoot(), getValue(LHS), getValue(RHS), + getValue(Size), MachinePointerInfo(LHS), MachinePointerInfo(RHS)); + if (Res.first.getNode()) { + processIntegerCallValue(I, Res.first, true); + PendingLoads.push_back(Res.second); + return true; + } + + // memcmp(S1,S2,2) != 0 -> (*(short*)LHS != *(short*)RHS) != 0 + // memcmp(S1,S2,4) != 0 -> (*(int*)LHS != *(int*)RHS) != 0 + if (!CSize || !isOnlyUsedInZeroEqualityComparison(&I)) + return false; + + // If the target has a fast compare for the given size, it will return a + // preferred load type for that size. Require that the load VT is legal and + // that the target supports unaligned loads of that type. Otherwise, return + // INVALID. + auto hasFastLoadsAndCompare = [&](unsigned NumBits) { + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + MVT LVT = TLI.hasFastEqualityCompare(NumBits); + if (LVT != MVT::INVALID_SIMPLE_VALUE_TYPE) { + // TODO: Handle 5 byte compare as 4-byte + 1 byte. + // TODO: Handle 8 byte compare on x86-32 as two 32-bit loads. + // TODO: Check alignment of src and dest ptrs. + unsigned DstAS = LHS->getType()->getPointerAddressSpace(); + unsigned SrcAS = RHS->getType()->getPointerAddressSpace(); + if (!TLI.isTypeLegal(LVT) || + !TLI.allowsMisalignedMemoryAccesses(LVT, SrcAS) || + !TLI.allowsMisalignedMemoryAccesses(LVT, DstAS)) + LVT = MVT::INVALID_SIMPLE_VALUE_TYPE; + } + + return LVT; + }; + + // This turns into unaligned loads. We only do this if the target natively + // supports the MVT we'll be loading or if it is small enough (<= 4) that + // we'll only produce a small number of byte loads. + MVT LoadVT; + unsigned NumBitsToCompare = CSize->getZExtValue() * 8; + switch (NumBitsToCompare) { + default: + return false; + case 16: + LoadVT = MVT::i16; + break; + case 32: + LoadVT = MVT::i32; + break; + case 64: + case 128: + case 256: + LoadVT = hasFastLoadsAndCompare(NumBitsToCompare); + break; + } + + if (LoadVT == MVT::INVALID_SIMPLE_VALUE_TYPE) + return false; + + SDValue LoadL = getMemCmpLoad(LHS, LoadVT, *this); + SDValue LoadR = getMemCmpLoad(RHS, LoadVT, *this); + + // Bitcast to a wide integer type if the loads are vectors. + if (LoadVT.isVector()) { + EVT CmpVT = EVT::getIntegerVT(LHS->getContext(), LoadVT.getSizeInBits()); + LoadL = DAG.getBitcast(CmpVT, LoadL); + LoadR = DAG.getBitcast(CmpVT, LoadR); + } + + SDValue Cmp = DAG.getSetCC(getCurSDLoc(), MVT::i1, LoadL, LoadR, ISD::SETNE); + processIntegerCallValue(I, Cmp, false); + return true; +} + +/// See if we can lower a memchr call into an optimized form. If so, return +/// true and lower it. Otherwise return false, and it will be lowered like a +/// normal call. +/// The caller already checked that \p I calls the appropriate LibFunc with a +/// correct prototype. +bool SelectionDAGBuilder::visitMemChrCall(const CallInst &I) { + const Value *Src = I.getArgOperand(0); + const Value *Char = I.getArgOperand(1); + const Value *Length = I.getArgOperand(2); + + const SelectionDAGTargetInfo &TSI = DAG.getSelectionDAGInfo(); + std::pair<SDValue, SDValue> Res = + TSI.EmitTargetCodeForMemchr(DAG, getCurSDLoc(), DAG.getRoot(), + getValue(Src), getValue(Char), getValue(Length), + MachinePointerInfo(Src)); + if (Res.first.getNode()) { + setValue(&I, Res.first); + PendingLoads.push_back(Res.second); + return true; + } + + return false; +} + +/// See if we can lower a mempcpy call into an optimized form. If so, return +/// true and lower it. Otherwise return false, and it will be lowered like a +/// normal call. +/// The caller already checked that \p I calls the appropriate LibFunc with a +/// correct prototype. +bool SelectionDAGBuilder::visitMemPCpyCall(const CallInst &I) { + SDValue Dst = getValue(I.getArgOperand(0)); + SDValue Src = getValue(I.getArgOperand(1)); + SDValue Size = getValue(I.getArgOperand(2)); + + unsigned DstAlign = DAG.InferPtrAlignment(Dst); + unsigned SrcAlign = DAG.InferPtrAlignment(Src); + unsigned Align = std::min(DstAlign, SrcAlign); + if (Align == 0) // Alignment of one or both could not be inferred. + Align = 1; // 0 and 1 both specify no alignment, but 0 is reserved. + + bool isVol = false; + SDLoc sdl = getCurSDLoc(); + + // In the mempcpy context we need to pass in a false value for isTailCall + // because the return pointer needs to be adjusted by the size of + // the copied memory. + SDValue Root = isVol ? getRoot() : getMemoryRoot(); + SDValue MC = DAG.getMemcpy(Root, sdl, Dst, Src, Size, Align, isVol, + false, /*isTailCall=*/false, + MachinePointerInfo(I.getArgOperand(0)), + MachinePointerInfo(I.getArgOperand(1))); + assert(MC.getNode() != nullptr && + "** memcpy should not be lowered as TailCall in mempcpy context **"); + DAG.setRoot(MC); + + // Check if Size needs to be truncated or extended. + Size = DAG.getSExtOrTrunc(Size, sdl, Dst.getValueType()); + + // Adjust return pointer to point just past the last dst byte. + SDValue DstPlusSize = DAG.getNode(ISD::ADD, sdl, Dst.getValueType(), + Dst, Size); + setValue(&I, DstPlusSize); + return true; +} + +/// See if we can lower a strcpy call into an optimized form. If so, return +/// true and lower it, otherwise return false and it will be lowered like a +/// normal call. +/// The caller already checked that \p I calls the appropriate LibFunc with a +/// correct prototype. +bool SelectionDAGBuilder::visitStrCpyCall(const CallInst &I, bool isStpcpy) { + const Value *Arg0 = I.getArgOperand(0), *Arg1 = I.getArgOperand(1); + + const SelectionDAGTargetInfo &TSI = DAG.getSelectionDAGInfo(); + std::pair<SDValue, SDValue> Res = + TSI.EmitTargetCodeForStrcpy(DAG, getCurSDLoc(), getRoot(), + getValue(Arg0), getValue(Arg1), + MachinePointerInfo(Arg0), + MachinePointerInfo(Arg1), isStpcpy); + if (Res.first.getNode()) { + setValue(&I, Res.first); + DAG.setRoot(Res.second); + return true; + } + + return false; +} + +/// See if we can lower a strcmp call into an optimized form. If so, return +/// true and lower it, otherwise return false and it will be lowered like a +/// normal call. +/// The caller already checked that \p I calls the appropriate LibFunc with a +/// correct prototype. +bool SelectionDAGBuilder::visitStrCmpCall(const CallInst &I) { + const Value *Arg0 = I.getArgOperand(0), *Arg1 = I.getArgOperand(1); + + const SelectionDAGTargetInfo &TSI = DAG.getSelectionDAGInfo(); + std::pair<SDValue, SDValue> Res = + TSI.EmitTargetCodeForStrcmp(DAG, getCurSDLoc(), DAG.getRoot(), + getValue(Arg0), getValue(Arg1), + MachinePointerInfo(Arg0), + MachinePointerInfo(Arg1)); + if (Res.first.getNode()) { + processIntegerCallValue(I, Res.first, true); + PendingLoads.push_back(Res.second); + return true; + } + + return false; +} + +/// See if we can lower a strlen call into an optimized form. If so, return +/// true and lower it, otherwise return false and it will be lowered like a +/// normal call. +/// The caller already checked that \p I calls the appropriate LibFunc with a +/// correct prototype. +bool SelectionDAGBuilder::visitStrLenCall(const CallInst &I) { + const Value *Arg0 = I.getArgOperand(0); + + const SelectionDAGTargetInfo &TSI = DAG.getSelectionDAGInfo(); + std::pair<SDValue, SDValue> Res = + TSI.EmitTargetCodeForStrlen(DAG, getCurSDLoc(), DAG.getRoot(), + getValue(Arg0), MachinePointerInfo(Arg0)); + if (Res.first.getNode()) { + processIntegerCallValue(I, Res.first, false); + PendingLoads.push_back(Res.second); + return true; + } + + return false; +} + +/// See if we can lower a strnlen call into an optimized form. If so, return +/// true and lower it, otherwise return false and it will be lowered like a +/// normal call. +/// The caller already checked that \p I calls the appropriate LibFunc with a +/// correct prototype. +bool SelectionDAGBuilder::visitStrNLenCall(const CallInst &I) { + const Value *Arg0 = I.getArgOperand(0), *Arg1 = I.getArgOperand(1); + + const SelectionDAGTargetInfo &TSI = DAG.getSelectionDAGInfo(); + std::pair<SDValue, SDValue> Res = + TSI.EmitTargetCodeForStrnlen(DAG, getCurSDLoc(), DAG.getRoot(), + getValue(Arg0), getValue(Arg1), + MachinePointerInfo(Arg0)); + if (Res.first.getNode()) { + processIntegerCallValue(I, Res.first, false); + PendingLoads.push_back(Res.second); + return true; + } + + return false; +} + +/// See if we can lower a unary floating-point operation into an SDNode with +/// the specified Opcode. If so, return true and lower it, otherwise return +/// false and it will be lowered like a normal call. +/// The caller already checked that \p I calls the appropriate LibFunc with a +/// correct prototype. +bool SelectionDAGBuilder::visitUnaryFloatCall(const CallInst &I, + unsigned Opcode) { + // We already checked this call's prototype; verify it doesn't modify errno. + if (!I.onlyReadsMemory()) + return false; + + SDValue Tmp = getValue(I.getArgOperand(0)); + setValue(&I, DAG.getNode(Opcode, getCurSDLoc(), Tmp.getValueType(), Tmp)); + return true; +} + +/// See if we can lower a binary floating-point operation into an SDNode with +/// the specified Opcode. If so, return true and lower it. Otherwise return +/// false, and it will be lowered like a normal call. +/// The caller already checked that \p I calls the appropriate LibFunc with a +/// correct prototype. +bool SelectionDAGBuilder::visitBinaryFloatCall(const CallInst &I, + unsigned Opcode) { + // We already checked this call's prototype; verify it doesn't modify errno. + if (!I.onlyReadsMemory()) + return false; + + SDValue Tmp0 = getValue(I.getArgOperand(0)); + SDValue Tmp1 = getValue(I.getArgOperand(1)); + EVT VT = Tmp0.getValueType(); + setValue(&I, DAG.getNode(Opcode, getCurSDLoc(), VT, Tmp0, Tmp1)); + return true; +} + +void SelectionDAGBuilder::visitCall(const CallInst &I) { + // Handle inline assembly differently. + if (isa<InlineAsm>(I.getCalledValue())) { + visitInlineAsm(&I); + return; + } + + if (Function *F = I.getCalledFunction()) { + if (F->isDeclaration()) { + // Is this an LLVM intrinsic or a target-specific intrinsic? + unsigned IID = F->getIntrinsicID(); + if (!IID) + if (const TargetIntrinsicInfo *II = TM.getIntrinsicInfo()) + IID = II->getIntrinsicID(F); + + if (IID) { + visitIntrinsicCall(I, IID); + return; + } + } + + // Check for well-known libc/libm calls. If the function is internal, it + // can't be a library call. Don't do the check if marked as nobuiltin for + // some reason or the call site requires strict floating point semantics. + LibFunc Func; + if (!I.isNoBuiltin() && !I.isStrictFP() && !F->hasLocalLinkage() && + F->hasName() && LibInfo->getLibFunc(*F, Func) && + LibInfo->hasOptimizedCodeGen(Func)) { + switch (Func) { + default: break; + case LibFunc_copysign: + case LibFunc_copysignf: + case LibFunc_copysignl: + // We already checked this call's prototype; verify it doesn't modify + // errno. + if (I.onlyReadsMemory()) { + SDValue LHS = getValue(I.getArgOperand(0)); + SDValue RHS = getValue(I.getArgOperand(1)); + setValue(&I, DAG.getNode(ISD::FCOPYSIGN, getCurSDLoc(), + LHS.getValueType(), LHS, RHS)); + return; + } + break; + case LibFunc_fabs: + case LibFunc_fabsf: + case LibFunc_fabsl: + if (visitUnaryFloatCall(I, ISD::FABS)) + return; + break; + case LibFunc_fmin: + case LibFunc_fminf: + case LibFunc_fminl: + if (visitBinaryFloatCall(I, ISD::FMINNUM)) + return; + break; + case LibFunc_fmax: + case LibFunc_fmaxf: + case LibFunc_fmaxl: + if (visitBinaryFloatCall(I, ISD::FMAXNUM)) + return; + break; + case LibFunc_sin: + case LibFunc_sinf: + case LibFunc_sinl: + if (visitUnaryFloatCall(I, ISD::FSIN)) + return; + break; + case LibFunc_cos: + case LibFunc_cosf: + case LibFunc_cosl: + if (visitUnaryFloatCall(I, ISD::FCOS)) + return; + break; + case LibFunc_sqrt: + case LibFunc_sqrtf: + case LibFunc_sqrtl: + case LibFunc_sqrt_finite: + case LibFunc_sqrtf_finite: + case LibFunc_sqrtl_finite: + if (visitUnaryFloatCall(I, ISD::FSQRT)) + return; + break; + case LibFunc_floor: + case LibFunc_floorf: + case LibFunc_floorl: + if (visitUnaryFloatCall(I, ISD::FFLOOR)) + return; + break; + case LibFunc_nearbyint: + case LibFunc_nearbyintf: + case LibFunc_nearbyintl: + if (visitUnaryFloatCall(I, ISD::FNEARBYINT)) + return; + break; + case LibFunc_ceil: + case LibFunc_ceilf: + case LibFunc_ceill: + if (visitUnaryFloatCall(I, ISD::FCEIL)) + return; + break; + case LibFunc_rint: + case LibFunc_rintf: + case LibFunc_rintl: + if (visitUnaryFloatCall(I, ISD::FRINT)) + return; + break; + case LibFunc_round: + case LibFunc_roundf: + case LibFunc_roundl: + if (visitUnaryFloatCall(I, ISD::FROUND)) + return; + break; + case LibFunc_trunc: + case LibFunc_truncf: + case LibFunc_truncl: + if (visitUnaryFloatCall(I, ISD::FTRUNC)) + return; + break; + case LibFunc_log2: + case LibFunc_log2f: + case LibFunc_log2l: + if (visitUnaryFloatCall(I, ISD::FLOG2)) + return; + break; + case LibFunc_exp2: + case LibFunc_exp2f: + case LibFunc_exp2l: + if (visitUnaryFloatCall(I, ISD::FEXP2)) + return; + break; + case LibFunc_memcmp: + if (visitMemCmpCall(I)) + return; + break; + case LibFunc_mempcpy: + if (visitMemPCpyCall(I)) + return; + break; + case LibFunc_memchr: + if (visitMemChrCall(I)) + return; + break; + case LibFunc_strcpy: + if (visitStrCpyCall(I, false)) + return; + break; + case LibFunc_stpcpy: + if (visitStrCpyCall(I, true)) + return; + break; + case LibFunc_strcmp: + if (visitStrCmpCall(I)) + return; + break; + case LibFunc_strlen: + if (visitStrLenCall(I)) + return; + break; + case LibFunc_strnlen: + if (visitStrNLenCall(I)) + return; + break; + } + } + } + + // Deopt bundles are lowered in LowerCallSiteWithDeoptBundle, and we don't + // have to do anything here to lower funclet bundles. + // CFGuardTarget bundles are lowered in LowerCallTo. + assert(!I.hasOperandBundlesOtherThan({LLVMContext::OB_deopt, + LLVMContext::OB_funclet, + LLVMContext::OB_cfguardtarget}) && + "Cannot lower calls with arbitrary operand bundles!"); + + SDValue Callee = getValue(I.getCalledValue()); + + if (I.countOperandBundlesOfType(LLVMContext::OB_deopt)) + LowerCallSiteWithDeoptBundle(&I, Callee, nullptr); + else + // Check if we can potentially perform a tail call. More detailed checking + // is be done within LowerCallTo, after more information about the call is + // known. + LowerCallTo(&I, Callee, I.isTailCall()); +} + +namespace { + +/// AsmOperandInfo - This contains information for each constraint that we are +/// lowering. +class SDISelAsmOperandInfo : public TargetLowering::AsmOperandInfo { +public: + /// CallOperand - If this is the result output operand or a clobber + /// this is null, otherwise it is the incoming operand to the CallInst. + /// This gets modified as the asm is processed. + SDValue CallOperand; + + /// AssignedRegs - If this is a register or register class operand, this + /// contains the set of register corresponding to the operand. + RegsForValue AssignedRegs; + + explicit SDISelAsmOperandInfo(const TargetLowering::AsmOperandInfo &info) + : TargetLowering::AsmOperandInfo(info), CallOperand(nullptr, 0) { + } + + /// Whether or not this operand accesses memory + bool hasMemory(const TargetLowering &TLI) const { + // Indirect operand accesses access memory. + if (isIndirect) + return true; + + for (const auto &Code : Codes) + if (TLI.getConstraintType(Code) == TargetLowering::C_Memory) + return true; + + return false; + } + + /// getCallOperandValEVT - Return the EVT of the Value* that this operand + /// corresponds to. If there is no Value* for this operand, it returns + /// MVT::Other. + EVT getCallOperandValEVT(LLVMContext &Context, const TargetLowering &TLI, + const DataLayout &DL) const { + if (!CallOperandVal) return MVT::Other; + + if (isa<BasicBlock>(CallOperandVal)) + return TLI.getPointerTy(DL); + + llvm::Type *OpTy = CallOperandVal->getType(); + + // FIXME: code duplicated from TargetLowering::ParseConstraints(). + // If this is an indirect operand, the operand is a pointer to the + // accessed type. + if (isIndirect) { + PointerType *PtrTy = dyn_cast<PointerType>(OpTy); + if (!PtrTy) + report_fatal_error("Indirect operand for inline asm not a pointer!"); + OpTy = PtrTy->getElementType(); + } + + // Look for vector wrapped in a struct. e.g. { <16 x i8> }. + if (StructType *STy = dyn_cast<StructType>(OpTy)) + if (STy->getNumElements() == 1) + OpTy = STy->getElementType(0); + + // If OpTy is not a single value, it may be a struct/union that we + // can tile with integers. + if (!OpTy->isSingleValueType() && OpTy->isSized()) { + unsigned BitSize = DL.getTypeSizeInBits(OpTy); + switch (BitSize) { + default: break; + case 1: + case 8: + case 16: + case 32: + case 64: + case 128: + OpTy = IntegerType::get(Context, BitSize); + break; + } + } + + return TLI.getValueType(DL, OpTy, true); + } +}; + +using SDISelAsmOperandInfoVector = SmallVector<SDISelAsmOperandInfo, 16>; + +} // end anonymous namespace + +/// Make sure that the output operand \p OpInfo and its corresponding input +/// operand \p MatchingOpInfo have compatible constraint types (otherwise error +/// out). +static void patchMatchingInput(const SDISelAsmOperandInfo &OpInfo, + SDISelAsmOperandInfo &MatchingOpInfo, + SelectionDAG &DAG) { + if (OpInfo.ConstraintVT == MatchingOpInfo.ConstraintVT) + return; + + const TargetRegisterInfo *TRI = DAG.getSubtarget().getRegisterInfo(); + const auto &TLI = DAG.getTargetLoweringInfo(); + + std::pair<unsigned, const TargetRegisterClass *> MatchRC = + TLI.getRegForInlineAsmConstraint(TRI, OpInfo.ConstraintCode, + OpInfo.ConstraintVT); + std::pair<unsigned, const TargetRegisterClass *> InputRC = + TLI.getRegForInlineAsmConstraint(TRI, MatchingOpInfo.ConstraintCode, + MatchingOpInfo.ConstraintVT); + if ((OpInfo.ConstraintVT.isInteger() != + MatchingOpInfo.ConstraintVT.isInteger()) || + (MatchRC.second != InputRC.second)) { + // FIXME: error out in a more elegant fashion + report_fatal_error("Unsupported asm: input constraint" + " with a matching output constraint of" + " incompatible type!"); + } + MatchingOpInfo.ConstraintVT = OpInfo.ConstraintVT; +} + +/// Get a direct memory input to behave well as an indirect operand. +/// This may introduce stores, hence the need for a \p Chain. +/// \return The (possibly updated) chain. +static SDValue getAddressForMemoryInput(SDValue Chain, const SDLoc &Location, + SDISelAsmOperandInfo &OpInfo, + SelectionDAG &DAG) { + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + + // If we don't have an indirect input, put it in the constpool if we can, + // otherwise spill it to a stack slot. + // TODO: This isn't quite right. We need to handle these according to + // the addressing mode that the constraint wants. Also, this may take + // an additional register for the computation and we don't want that + // either. + + // If the operand is a float, integer, or vector constant, spill to a + // constant pool entry to get its address. + const Value *OpVal = OpInfo.CallOperandVal; + if (isa<ConstantFP>(OpVal) || isa<ConstantInt>(OpVal) || + isa<ConstantVector>(OpVal) || isa<ConstantDataVector>(OpVal)) { + OpInfo.CallOperand = DAG.getConstantPool( + cast<Constant>(OpVal), TLI.getPointerTy(DAG.getDataLayout())); + return Chain; + } + + // Otherwise, create a stack slot and emit a store to it before the asm. + Type *Ty = OpVal->getType(); + auto &DL = DAG.getDataLayout(); + uint64_t TySize = DL.getTypeAllocSize(Ty); + unsigned Align = DL.getPrefTypeAlignment(Ty); + MachineFunction &MF = DAG.getMachineFunction(); + int SSFI = MF.getFrameInfo().CreateStackObject(TySize, Align, false); + SDValue StackSlot = DAG.getFrameIndex(SSFI, TLI.getFrameIndexTy(DL)); + Chain = DAG.getTruncStore(Chain, Location, OpInfo.CallOperand, StackSlot, + MachinePointerInfo::getFixedStack(MF, SSFI), + TLI.getMemValueType(DL, Ty)); + OpInfo.CallOperand = StackSlot; + + return Chain; +} + +/// GetRegistersForValue - Assign registers (virtual or physical) for the +/// specified operand. We prefer to assign virtual registers, to allow the +/// register allocator to handle the assignment process. However, if the asm +/// uses features that we can't model on machineinstrs, we have SDISel do the +/// allocation. This produces generally horrible, but correct, code. +/// +/// OpInfo describes the operand +/// RefOpInfo describes the matching operand if any, the operand otherwise +static void GetRegistersForValue(SelectionDAG &DAG, const SDLoc &DL, + SDISelAsmOperandInfo &OpInfo, + SDISelAsmOperandInfo &RefOpInfo) { + LLVMContext &Context = *DAG.getContext(); + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + + MachineFunction &MF = DAG.getMachineFunction(); + SmallVector<unsigned, 4> Regs; + const TargetRegisterInfo &TRI = *MF.getSubtarget().getRegisterInfo(); + + // No work to do for memory operations. + if (OpInfo.ConstraintType == TargetLowering::C_Memory) + return; + + // If this is a constraint for a single physreg, or a constraint for a + // register class, find it. + unsigned AssignedReg; + const TargetRegisterClass *RC; + std::tie(AssignedReg, RC) = TLI.getRegForInlineAsmConstraint( + &TRI, RefOpInfo.ConstraintCode, RefOpInfo.ConstraintVT); + // RC is unset only on failure. Return immediately. + if (!RC) + return; + + // Get the actual register value type. This is important, because the user + // may have asked for (e.g.) the AX register in i32 type. We need to + // remember that AX is actually i16 to get the right extension. + const MVT RegVT = *TRI.legalclasstypes_begin(*RC); + + if (OpInfo.ConstraintVT != MVT::Other) { + // If this is an FP operand in an integer register (or visa versa), or more + // generally if the operand value disagrees with the register class we plan + // to stick it in, fix the operand type. + // + // If this is an input value, the bitcast to the new type is done now. + // Bitcast for output value is done at the end of visitInlineAsm(). + if ((OpInfo.Type == InlineAsm::isOutput || + OpInfo.Type == InlineAsm::isInput) && + !TRI.isTypeLegalForClass(*RC, OpInfo.ConstraintVT)) { + // Try to convert to the first EVT that the reg class contains. If the + // types are identical size, use a bitcast to convert (e.g. two differing + // vector types). Note: output bitcast is done at the end of + // visitInlineAsm(). + if (RegVT.getSizeInBits() == OpInfo.ConstraintVT.getSizeInBits()) { + // Exclude indirect inputs while they are unsupported because the code + // to perform the load is missing and thus OpInfo.CallOperand still + // refers to the input address rather than the pointed-to value. + if (OpInfo.Type == InlineAsm::isInput && !OpInfo.isIndirect) + OpInfo.CallOperand = + DAG.getNode(ISD::BITCAST, DL, RegVT, OpInfo.CallOperand); + OpInfo.ConstraintVT = RegVT; + // If the operand is an FP value and we want it in integer registers, + // use the corresponding integer type. This turns an f64 value into + // i64, which can be passed with two i32 values on a 32-bit machine. + } else if (RegVT.isInteger() && OpInfo.ConstraintVT.isFloatingPoint()) { + MVT VT = MVT::getIntegerVT(OpInfo.ConstraintVT.getSizeInBits()); + if (OpInfo.Type == InlineAsm::isInput) + OpInfo.CallOperand = + DAG.getNode(ISD::BITCAST, DL, VT, OpInfo.CallOperand); + OpInfo.ConstraintVT = VT; + } + } + } + + // No need to allocate a matching input constraint since the constraint it's + // matching to has already been allocated. + if (OpInfo.isMatchingInputConstraint()) + return; + + EVT ValueVT = OpInfo.ConstraintVT; + if (OpInfo.ConstraintVT == MVT::Other) + ValueVT = RegVT; + + // Initialize NumRegs. + unsigned NumRegs = 1; + if (OpInfo.ConstraintVT != MVT::Other) + NumRegs = TLI.getNumRegisters(Context, OpInfo.ConstraintVT); + + // If this is a constraint for a specific physical register, like {r17}, + // assign it now. + + // If this associated to a specific register, initialize iterator to correct + // place. If virtual, make sure we have enough registers + + // Initialize iterator if necessary + TargetRegisterClass::iterator I = RC->begin(); + MachineRegisterInfo &RegInfo = MF.getRegInfo(); + + // Do not check for single registers. + if (AssignedReg) { + for (; *I != AssignedReg; ++I) + assert(I != RC->end() && "AssignedReg should be member of RC"); + } + + for (; NumRegs; --NumRegs, ++I) { + assert(I != RC->end() && "Ran out of registers to allocate!"); + Register R = AssignedReg ? Register(*I) : RegInfo.createVirtualRegister(RC); + Regs.push_back(R); + } + + OpInfo.AssignedRegs = RegsForValue(Regs, RegVT, ValueVT); +} + +static unsigned +findMatchingInlineAsmOperand(unsigned OperandNo, + const std::vector<SDValue> &AsmNodeOperands) { + // Scan until we find the definition we already emitted of this operand. + unsigned CurOp = InlineAsm::Op_FirstOperand; + for (; OperandNo; --OperandNo) { + // Advance to the next operand. + unsigned OpFlag = + cast<ConstantSDNode>(AsmNodeOperands[CurOp])->getZExtValue(); + assert((InlineAsm::isRegDefKind(OpFlag) || + InlineAsm::isRegDefEarlyClobberKind(OpFlag) || + InlineAsm::isMemKind(OpFlag)) && + "Skipped past definitions?"); + CurOp += InlineAsm::getNumOperandRegisters(OpFlag) + 1; + } + return CurOp; +} + +namespace { + +class ExtraFlags { + unsigned Flags = 0; + +public: + explicit ExtraFlags(ImmutableCallSite CS) { + const InlineAsm *IA = cast<InlineAsm>(CS.getCalledValue()); + if (IA->hasSideEffects()) + Flags |= InlineAsm::Extra_HasSideEffects; + if (IA->isAlignStack()) + Flags |= InlineAsm::Extra_IsAlignStack; + if (CS.isConvergent()) + Flags |= InlineAsm::Extra_IsConvergent; + Flags |= IA->getDialect() * InlineAsm::Extra_AsmDialect; + } + + void update(const TargetLowering::AsmOperandInfo &OpInfo) { + // Ideally, we would only check against memory constraints. However, the + // meaning of an Other constraint can be target-specific and we can't easily + // reason about it. Therefore, be conservative and set MayLoad/MayStore + // for Other constraints as well. + if (OpInfo.ConstraintType == TargetLowering::C_Memory || + OpInfo.ConstraintType == TargetLowering::C_Other) { + if (OpInfo.Type == InlineAsm::isInput) + Flags |= InlineAsm::Extra_MayLoad; + else if (OpInfo.Type == InlineAsm::isOutput) + Flags |= InlineAsm::Extra_MayStore; + else if (OpInfo.Type == InlineAsm::isClobber) + Flags |= (InlineAsm::Extra_MayLoad | InlineAsm::Extra_MayStore); + } + } + + unsigned get() const { return Flags; } +}; + +} // end anonymous namespace + +/// visitInlineAsm - Handle a call to an InlineAsm object. +void SelectionDAGBuilder::visitInlineAsm(ImmutableCallSite CS) { + const InlineAsm *IA = cast<InlineAsm>(CS.getCalledValue()); + + /// ConstraintOperands - Information about all of the constraints. + SDISelAsmOperandInfoVector ConstraintOperands; + + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + TargetLowering::AsmOperandInfoVector TargetConstraints = TLI.ParseConstraints( + DAG.getDataLayout(), DAG.getSubtarget().getRegisterInfo(), CS); + + // First Pass: Calculate HasSideEffects and ExtraFlags (AlignStack, + // AsmDialect, MayLoad, MayStore). + bool HasSideEffect = IA->hasSideEffects(); + ExtraFlags ExtraInfo(CS); + + unsigned ArgNo = 0; // ArgNo - The argument of the CallInst. + unsigned ResNo = 0; // ResNo - The result number of the next output. + for (auto &T : TargetConstraints) { + ConstraintOperands.push_back(SDISelAsmOperandInfo(T)); + SDISelAsmOperandInfo &OpInfo = ConstraintOperands.back(); + + // Compute the value type for each operand. + if (OpInfo.Type == InlineAsm::isInput || + (OpInfo.Type == InlineAsm::isOutput && OpInfo.isIndirect)) { + OpInfo.CallOperandVal = const_cast<Value *>(CS.getArgument(ArgNo++)); + + // Process the call argument. BasicBlocks are labels, currently appearing + // only in asm's. + const Instruction *I = CS.getInstruction(); + if (isa<CallBrInst>(I) && + (ArgNo - 1) >= (cast<CallBrInst>(I)->getNumArgOperands() - + cast<CallBrInst>(I)->getNumIndirectDests())) { + const auto *BA = cast<BlockAddress>(OpInfo.CallOperandVal); + EVT VT = TLI.getValueType(DAG.getDataLayout(), BA->getType(), true); + OpInfo.CallOperand = DAG.getTargetBlockAddress(BA, VT); + } else if (const auto *BB = dyn_cast<BasicBlock>(OpInfo.CallOperandVal)) { + OpInfo.CallOperand = DAG.getBasicBlock(FuncInfo.MBBMap[BB]); + } else { + OpInfo.CallOperand = getValue(OpInfo.CallOperandVal); + } + + OpInfo.ConstraintVT = + OpInfo + .getCallOperandValEVT(*DAG.getContext(), TLI, DAG.getDataLayout()) + .getSimpleVT(); + } else if (OpInfo.Type == InlineAsm::isOutput && !OpInfo.isIndirect) { + // The return value of the call is this value. As such, there is no + // corresponding argument. + assert(!CS.getType()->isVoidTy() && "Bad inline asm!"); + if (StructType *STy = dyn_cast<StructType>(CS.getType())) { + OpInfo.ConstraintVT = TLI.getSimpleValueType( + DAG.getDataLayout(), STy->getElementType(ResNo)); + } else { + assert(ResNo == 0 && "Asm only has one result!"); + OpInfo.ConstraintVT = + TLI.getSimpleValueType(DAG.getDataLayout(), CS.getType()); + } + ++ResNo; + } else { + OpInfo.ConstraintVT = MVT::Other; + } + + if (!HasSideEffect) + HasSideEffect = OpInfo.hasMemory(TLI); + + // Determine if this InlineAsm MayLoad or MayStore based on the constraints. + // FIXME: Could we compute this on OpInfo rather than T? + + // Compute the constraint code and ConstraintType to use. + TLI.ComputeConstraintToUse(T, SDValue()); + + if (T.ConstraintType == TargetLowering::C_Immediate && + OpInfo.CallOperand && !isa<ConstantSDNode>(OpInfo.CallOperand)) + // We've delayed emitting a diagnostic like the "n" constraint because + // inlining could cause an integer showing up. + return emitInlineAsmError( + CS, "constraint '" + Twine(T.ConstraintCode) + "' expects an " + "integer constant expression"); + + ExtraInfo.update(T); + } + + + // We won't need to flush pending loads if this asm doesn't touch + // memory and is nonvolatile. + SDValue Flag, Chain = (HasSideEffect) ? getRoot() : DAG.getRoot(); + + bool IsCallBr = isa<CallBrInst>(CS.getInstruction()); + if (IsCallBr) { + // If this is a callbr we need to flush pending exports since inlineasm_br + // is a terminator. We need to do this before nodes are glued to + // the inlineasm_br node. + Chain = getControlRoot(); + } + + // Second pass over the constraints: compute which constraint option to use. + for (SDISelAsmOperandInfo &OpInfo : ConstraintOperands) { + // If this is an output operand with a matching input operand, look up the + // matching input. If their types mismatch, e.g. one is an integer, the + // other is floating point, or their sizes are different, flag it as an + // error. + if (OpInfo.hasMatchingInput()) { + SDISelAsmOperandInfo &Input = ConstraintOperands[OpInfo.MatchingInput]; + patchMatchingInput(OpInfo, Input, DAG); + } + + // Compute the constraint code and ConstraintType to use. + TLI.ComputeConstraintToUse(OpInfo, OpInfo.CallOperand, &DAG); + + if (OpInfo.ConstraintType == TargetLowering::C_Memory && + OpInfo.Type == InlineAsm::isClobber) + continue; + + // If this is a memory input, and if the operand is not indirect, do what we + // need to provide an address for the memory input. + if (OpInfo.ConstraintType == TargetLowering::C_Memory && + !OpInfo.isIndirect) { + assert((OpInfo.isMultipleAlternative || + (OpInfo.Type == InlineAsm::isInput)) && + "Can only indirectify direct input operands!"); + + // Memory operands really want the address of the value. + Chain = getAddressForMemoryInput(Chain, getCurSDLoc(), OpInfo, DAG); + + // There is no longer a Value* corresponding to this operand. + OpInfo.CallOperandVal = nullptr; + + // It is now an indirect operand. + OpInfo.isIndirect = true; + } + + } + + // AsmNodeOperands - The operands for the ISD::INLINEASM node. + std::vector<SDValue> AsmNodeOperands; + AsmNodeOperands.push_back(SDValue()); // reserve space for input chain + AsmNodeOperands.push_back(DAG.getTargetExternalSymbol( + IA->getAsmString().c_str(), TLI.getPointerTy(DAG.getDataLayout()))); + + // If we have a !srcloc metadata node associated with it, we want to attach + // this to the ultimately generated inline asm machineinstr. To do this, we + // pass in the third operand as this (potentially null) inline asm MDNode. + const MDNode *SrcLoc = CS.getInstruction()->getMetadata("srcloc"); + AsmNodeOperands.push_back(DAG.getMDNode(SrcLoc)); + + // Remember the HasSideEffect, AlignStack, AsmDialect, MayLoad and MayStore + // bits as operand 3. + AsmNodeOperands.push_back(DAG.getTargetConstant( + ExtraInfo.get(), getCurSDLoc(), TLI.getPointerTy(DAG.getDataLayout()))); + + // Third pass: Loop over operands to prepare DAG-level operands.. As part of + // this, assign virtual and physical registers for inputs and otput. + for (SDISelAsmOperandInfo &OpInfo : ConstraintOperands) { + // Assign Registers. + SDISelAsmOperandInfo &RefOpInfo = + OpInfo.isMatchingInputConstraint() + ? ConstraintOperands[OpInfo.getMatchedOperand()] + : OpInfo; + GetRegistersForValue(DAG, getCurSDLoc(), OpInfo, RefOpInfo); + + switch (OpInfo.Type) { + case InlineAsm::isOutput: + if (OpInfo.ConstraintType == TargetLowering::C_Memory) { + unsigned ConstraintID = + TLI.getInlineAsmMemConstraint(OpInfo.ConstraintCode); + assert(ConstraintID != InlineAsm::Constraint_Unknown && + "Failed to convert memory constraint code to constraint id."); + + // Add information to the INLINEASM node to know about this output. + unsigned OpFlags = InlineAsm::getFlagWord(InlineAsm::Kind_Mem, 1); + OpFlags = InlineAsm::getFlagWordForMem(OpFlags, ConstraintID); + AsmNodeOperands.push_back(DAG.getTargetConstant(OpFlags, getCurSDLoc(), + MVT::i32)); + AsmNodeOperands.push_back(OpInfo.CallOperand); + } else { + // Otherwise, this outputs to a register (directly for C_Register / + // C_RegisterClass, and a target-defined fashion for + // C_Immediate/C_Other). Find a register that we can use. + if (OpInfo.AssignedRegs.Regs.empty()) { + emitInlineAsmError( + CS, "couldn't allocate output register for constraint '" + + Twine(OpInfo.ConstraintCode) + "'"); + return; + } + + // Add information to the INLINEASM node to know that this register is + // set. + OpInfo.AssignedRegs.AddInlineAsmOperands( + OpInfo.isEarlyClobber ? InlineAsm::Kind_RegDefEarlyClobber + : InlineAsm::Kind_RegDef, + false, 0, getCurSDLoc(), DAG, AsmNodeOperands); + } + break; + + case InlineAsm::isInput: { + SDValue InOperandVal = OpInfo.CallOperand; + + if (OpInfo.isMatchingInputConstraint()) { + // If this is required to match an output register we have already set, + // just use its register. + auto CurOp = findMatchingInlineAsmOperand(OpInfo.getMatchedOperand(), + AsmNodeOperands); + unsigned OpFlag = + cast<ConstantSDNode>(AsmNodeOperands[CurOp])->getZExtValue(); + if (InlineAsm::isRegDefKind(OpFlag) || + InlineAsm::isRegDefEarlyClobberKind(OpFlag)) { + // Add (OpFlag&0xffff)>>3 registers to MatchedRegs. + if (OpInfo.isIndirect) { + // This happens on gcc/testsuite/gcc.dg/pr8788-1.c + emitInlineAsmError(CS, "inline asm not supported yet:" + " don't know how to handle tied " + "indirect register inputs"); + return; + } + + MVT RegVT = AsmNodeOperands[CurOp+1].getSimpleValueType(); + SmallVector<unsigned, 4> Regs; + + if (const TargetRegisterClass *RC = TLI.getRegClassFor(RegVT)) { + unsigned NumRegs = InlineAsm::getNumOperandRegisters(OpFlag); + MachineRegisterInfo &RegInfo = + DAG.getMachineFunction().getRegInfo(); + for (unsigned i = 0; i != NumRegs; ++i) + Regs.push_back(RegInfo.createVirtualRegister(RC)); + } else { + emitInlineAsmError(CS, "inline asm error: This value type register " + "class is not natively supported!"); + return; + } + + RegsForValue MatchedRegs(Regs, RegVT, InOperandVal.getValueType()); + + SDLoc dl = getCurSDLoc(); + // Use the produced MatchedRegs object to + MatchedRegs.getCopyToRegs(InOperandVal, DAG, dl, Chain, &Flag, + CS.getInstruction()); + MatchedRegs.AddInlineAsmOperands(InlineAsm::Kind_RegUse, + true, OpInfo.getMatchedOperand(), dl, + DAG, AsmNodeOperands); + break; + } + + assert(InlineAsm::isMemKind(OpFlag) && "Unknown matching constraint!"); + assert(InlineAsm::getNumOperandRegisters(OpFlag) == 1 && + "Unexpected number of operands"); + // Add information to the INLINEASM node to know about this input. + // See InlineAsm.h isUseOperandTiedToDef. + OpFlag = InlineAsm::convertMemFlagWordToMatchingFlagWord(OpFlag); + OpFlag = InlineAsm::getFlagWordForMatchingOp(OpFlag, + OpInfo.getMatchedOperand()); + AsmNodeOperands.push_back(DAG.getTargetConstant( + OpFlag, getCurSDLoc(), TLI.getPointerTy(DAG.getDataLayout()))); + AsmNodeOperands.push_back(AsmNodeOperands[CurOp+1]); + break; + } + + // Treat indirect 'X' constraint as memory. + if (OpInfo.ConstraintType == TargetLowering::C_Other && + OpInfo.isIndirect) + OpInfo.ConstraintType = TargetLowering::C_Memory; + + if (OpInfo.ConstraintType == TargetLowering::C_Immediate || + OpInfo.ConstraintType == TargetLowering::C_Other) { + std::vector<SDValue> Ops; + TLI.LowerAsmOperandForConstraint(InOperandVal, OpInfo.ConstraintCode, + Ops, DAG); + if (Ops.empty()) { + if (OpInfo.ConstraintType == TargetLowering::C_Immediate) + if (isa<ConstantSDNode>(InOperandVal)) { + emitInlineAsmError(CS, "value out of range for constraint '" + + Twine(OpInfo.ConstraintCode) + "'"); + return; + } + + emitInlineAsmError(CS, "invalid operand for inline asm constraint '" + + Twine(OpInfo.ConstraintCode) + "'"); + return; + } + + // Add information to the INLINEASM node to know about this input. + unsigned ResOpType = + InlineAsm::getFlagWord(InlineAsm::Kind_Imm, Ops.size()); + AsmNodeOperands.push_back(DAG.getTargetConstant( + ResOpType, getCurSDLoc(), TLI.getPointerTy(DAG.getDataLayout()))); + AsmNodeOperands.insert(AsmNodeOperands.end(), Ops.begin(), Ops.end()); + break; + } + + if (OpInfo.ConstraintType == TargetLowering::C_Memory) { + assert(OpInfo.isIndirect && "Operand must be indirect to be a mem!"); + assert(InOperandVal.getValueType() == + TLI.getPointerTy(DAG.getDataLayout()) && + "Memory operands expect pointer values"); + + unsigned ConstraintID = + TLI.getInlineAsmMemConstraint(OpInfo.ConstraintCode); + assert(ConstraintID != InlineAsm::Constraint_Unknown && + "Failed to convert memory constraint code to constraint id."); + + // Add information to the INLINEASM node to know about this input. + unsigned ResOpType = InlineAsm::getFlagWord(InlineAsm::Kind_Mem, 1); + ResOpType = InlineAsm::getFlagWordForMem(ResOpType, ConstraintID); + AsmNodeOperands.push_back(DAG.getTargetConstant(ResOpType, + getCurSDLoc(), + MVT::i32)); + AsmNodeOperands.push_back(InOperandVal); + break; + } + + assert((OpInfo.ConstraintType == TargetLowering::C_RegisterClass || + OpInfo.ConstraintType == TargetLowering::C_Register) && + "Unknown constraint type!"); + + // TODO: Support this. + if (OpInfo.isIndirect) { + emitInlineAsmError( + CS, "Don't know how to handle indirect register inputs yet " + "for constraint '" + + Twine(OpInfo.ConstraintCode) + "'"); + return; + } + + // Copy the input into the appropriate registers. + if (OpInfo.AssignedRegs.Regs.empty()) { + emitInlineAsmError(CS, "couldn't allocate input reg for constraint '" + + Twine(OpInfo.ConstraintCode) + "'"); + return; + } + + SDLoc dl = getCurSDLoc(); + + OpInfo.AssignedRegs.getCopyToRegs(InOperandVal, DAG, dl, + Chain, &Flag, CS.getInstruction()); + + OpInfo.AssignedRegs.AddInlineAsmOperands(InlineAsm::Kind_RegUse, false, 0, + dl, DAG, AsmNodeOperands); + break; + } + case InlineAsm::isClobber: + // Add the clobbered value to the operand list, so that the register + // allocator is aware that the physreg got clobbered. + if (!OpInfo.AssignedRegs.Regs.empty()) + OpInfo.AssignedRegs.AddInlineAsmOperands(InlineAsm::Kind_Clobber, + false, 0, getCurSDLoc(), DAG, + AsmNodeOperands); + break; + } + } + + // Finish up input operands. Set the input chain and add the flag last. + AsmNodeOperands[InlineAsm::Op_InputChain] = Chain; + if (Flag.getNode()) AsmNodeOperands.push_back(Flag); + + unsigned ISDOpc = IsCallBr ? ISD::INLINEASM_BR : ISD::INLINEASM; + Chain = DAG.getNode(ISDOpc, getCurSDLoc(), + DAG.getVTList(MVT::Other, MVT::Glue), AsmNodeOperands); + Flag = Chain.getValue(1); + + // Do additional work to generate outputs. + + SmallVector<EVT, 1> ResultVTs; + SmallVector<SDValue, 1> ResultValues; + SmallVector<SDValue, 8> OutChains; + + llvm::Type *CSResultType = CS.getType(); + ArrayRef<Type *> ResultTypes; + if (StructType *StructResult = dyn_cast<StructType>(CSResultType)) + ResultTypes = StructResult->elements(); + else if (!CSResultType->isVoidTy()) + ResultTypes = makeArrayRef(CSResultType); + + auto CurResultType = ResultTypes.begin(); + auto handleRegAssign = [&](SDValue V) { + assert(CurResultType != ResultTypes.end() && "Unexpected value"); + assert((*CurResultType)->isSized() && "Unexpected unsized type"); + EVT ResultVT = TLI.getValueType(DAG.getDataLayout(), *CurResultType); + ++CurResultType; + // If the type of the inline asm call site return value is different but has + // same size as the type of the asm output bitcast it. One example of this + // is for vectors with different width / number of elements. This can + // happen for register classes that can contain multiple different value + // types. The preg or vreg allocated may not have the same VT as was + // expected. + // + // This can also happen for a return value that disagrees with the register + // class it is put in, eg. a double in a general-purpose register on a + // 32-bit machine. + if (ResultVT != V.getValueType() && + ResultVT.getSizeInBits() == V.getValueSizeInBits()) + V = DAG.getNode(ISD::BITCAST, getCurSDLoc(), ResultVT, V); + else if (ResultVT != V.getValueType() && ResultVT.isInteger() && + V.getValueType().isInteger()) { + // If a result value was tied to an input value, the computed result + // may have a wider width than the expected result. Extract the + // relevant portion. + V = DAG.getNode(ISD::TRUNCATE, getCurSDLoc(), ResultVT, V); + } + assert(ResultVT == V.getValueType() && "Asm result value mismatch!"); + ResultVTs.push_back(ResultVT); + ResultValues.push_back(V); + }; + + // Deal with output operands. + for (SDISelAsmOperandInfo &OpInfo : ConstraintOperands) { + if (OpInfo.Type == InlineAsm::isOutput) { + SDValue Val; + // Skip trivial output operands. + if (OpInfo.AssignedRegs.Regs.empty()) + continue; + + switch (OpInfo.ConstraintType) { + case TargetLowering::C_Register: + case TargetLowering::C_RegisterClass: + Val = OpInfo.AssignedRegs.getCopyFromRegs( + DAG, FuncInfo, getCurSDLoc(), Chain, &Flag, CS.getInstruction()); + break; + case TargetLowering::C_Immediate: + case TargetLowering::C_Other: + Val = TLI.LowerAsmOutputForConstraint(Chain, Flag, getCurSDLoc(), + OpInfo, DAG); + break; + case TargetLowering::C_Memory: + break; // Already handled. + case TargetLowering::C_Unknown: + assert(false && "Unexpected unknown constraint"); + } + + // Indirect output manifest as stores. Record output chains. + if (OpInfo.isIndirect) { + const Value *Ptr = OpInfo.CallOperandVal; + assert(Ptr && "Expected value CallOperandVal for indirect asm operand"); + SDValue Store = DAG.getStore(Chain, getCurSDLoc(), Val, getValue(Ptr), + MachinePointerInfo(Ptr)); + OutChains.push_back(Store); + } else { + // generate CopyFromRegs to associated registers. + assert(!CS.getType()->isVoidTy() && "Bad inline asm!"); + if (Val.getOpcode() == ISD::MERGE_VALUES) { + for (const SDValue &V : Val->op_values()) + handleRegAssign(V); + } else + handleRegAssign(Val); + } + } + } + + // Set results. + if (!ResultValues.empty()) { + assert(CurResultType == ResultTypes.end() && + "Mismatch in number of ResultTypes"); + assert(ResultValues.size() == ResultTypes.size() && + "Mismatch in number of output operands in asm result"); + + SDValue V = DAG.getNode(ISD::MERGE_VALUES, getCurSDLoc(), + DAG.getVTList(ResultVTs), ResultValues); + setValue(CS.getInstruction(), V); + } + + // Collect store chains. + if (!OutChains.empty()) + Chain = DAG.getNode(ISD::TokenFactor, getCurSDLoc(), MVT::Other, OutChains); + + // Only Update Root if inline assembly has a memory effect. + if (ResultValues.empty() || HasSideEffect || !OutChains.empty() || IsCallBr) + DAG.setRoot(Chain); +} + +void SelectionDAGBuilder::emitInlineAsmError(ImmutableCallSite CS, + const Twine &Message) { + LLVMContext &Ctx = *DAG.getContext(); + Ctx.emitError(CS.getInstruction(), Message); + + // Make sure we leave the DAG in a valid state + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + SmallVector<EVT, 1> ValueVTs; + ComputeValueVTs(TLI, DAG.getDataLayout(), CS->getType(), ValueVTs); + + if (ValueVTs.empty()) + return; + + SmallVector<SDValue, 1> Ops; + for (unsigned i = 0, e = ValueVTs.size(); i != e; ++i) + Ops.push_back(DAG.getUNDEF(ValueVTs[i])); + + setValue(CS.getInstruction(), DAG.getMergeValues(Ops, getCurSDLoc())); +} + +void SelectionDAGBuilder::visitVAStart(const CallInst &I) { + DAG.setRoot(DAG.getNode(ISD::VASTART, getCurSDLoc(), + MVT::Other, getRoot(), + getValue(I.getArgOperand(0)), + DAG.getSrcValue(I.getArgOperand(0)))); +} + +void SelectionDAGBuilder::visitVAArg(const VAArgInst &I) { + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + const DataLayout &DL = DAG.getDataLayout(); + SDValue V = DAG.getVAArg( + TLI.getMemValueType(DAG.getDataLayout(), I.getType()), getCurSDLoc(), + getRoot(), getValue(I.getOperand(0)), DAG.getSrcValue(I.getOperand(0)), + DL.getABITypeAlignment(I.getType())); + DAG.setRoot(V.getValue(1)); + + if (I.getType()->isPointerTy()) + V = DAG.getPtrExtOrTrunc( + V, getCurSDLoc(), TLI.getValueType(DAG.getDataLayout(), I.getType())); + setValue(&I, V); +} + +void SelectionDAGBuilder::visitVAEnd(const CallInst &I) { + DAG.setRoot(DAG.getNode(ISD::VAEND, getCurSDLoc(), + MVT::Other, getRoot(), + getValue(I.getArgOperand(0)), + DAG.getSrcValue(I.getArgOperand(0)))); +} + +void SelectionDAGBuilder::visitVACopy(const CallInst &I) { + DAG.setRoot(DAG.getNode(ISD::VACOPY, getCurSDLoc(), + MVT::Other, getRoot(), + getValue(I.getArgOperand(0)), + getValue(I.getArgOperand(1)), + DAG.getSrcValue(I.getArgOperand(0)), + DAG.getSrcValue(I.getArgOperand(1)))); +} + +SDValue SelectionDAGBuilder::lowerRangeToAssertZExt(SelectionDAG &DAG, + const Instruction &I, + SDValue Op) { + const MDNode *Range = I.getMetadata(LLVMContext::MD_range); + if (!Range) + return Op; + + ConstantRange CR = getConstantRangeFromMetadata(*Range); + if (CR.isFullSet() || CR.isEmptySet() || CR.isUpperWrapped()) + return Op; + + APInt Lo = CR.getUnsignedMin(); + if (!Lo.isMinValue()) + return Op; + + APInt Hi = CR.getUnsignedMax(); + unsigned Bits = std::max(Hi.getActiveBits(), + static_cast<unsigned>(IntegerType::MIN_INT_BITS)); + + EVT SmallVT = EVT::getIntegerVT(*DAG.getContext(), Bits); + + SDLoc SL = getCurSDLoc(); + + SDValue ZExt = DAG.getNode(ISD::AssertZext, SL, Op.getValueType(), Op, + DAG.getValueType(SmallVT)); + unsigned NumVals = Op.getNode()->getNumValues(); + if (NumVals == 1) + return ZExt; + + SmallVector<SDValue, 4> Ops; + + Ops.push_back(ZExt); + for (unsigned I = 1; I != NumVals; ++I) + Ops.push_back(Op.getValue(I)); + + return DAG.getMergeValues(Ops, SL); +} + +/// Populate a CallLowerinInfo (into \p CLI) based on the properties of +/// the call being lowered. +/// +/// This is a helper for lowering intrinsics that follow a target calling +/// convention or require stack pointer adjustment. Only a subset of the +/// intrinsic's operands need to participate in the calling convention. +void SelectionDAGBuilder::populateCallLoweringInfo( + TargetLowering::CallLoweringInfo &CLI, const CallBase *Call, + unsigned ArgIdx, unsigned NumArgs, SDValue Callee, Type *ReturnTy, + bool IsPatchPoint) { + TargetLowering::ArgListTy Args; + Args.reserve(NumArgs); + + // Populate the argument list. + // Attributes for args start at offset 1, after the return attribute. + for (unsigned ArgI = ArgIdx, ArgE = ArgIdx + NumArgs; + ArgI != ArgE; ++ArgI) { + const Value *V = Call->getOperand(ArgI); + + assert(!V->getType()->isEmptyTy() && "Empty type passed to intrinsic."); + + TargetLowering::ArgListEntry Entry; + Entry.Node = getValue(V); + Entry.Ty = V->getType(); + Entry.setAttributes(Call, ArgI); + Args.push_back(Entry); + } + + CLI.setDebugLoc(getCurSDLoc()) + .setChain(getRoot()) + .setCallee(Call->getCallingConv(), ReturnTy, Callee, std::move(Args)) + .setDiscardResult(Call->use_empty()) + .setIsPatchPoint(IsPatchPoint); +} + +/// Add a stack map intrinsic call's live variable operands to a stackmap +/// or patchpoint target node's operand list. +/// +/// Constants are converted to TargetConstants purely as an optimization to +/// avoid constant materialization and register allocation. +/// +/// FrameIndex operands are converted to TargetFrameIndex so that ISEL does not +/// generate addess computation nodes, and so FinalizeISel can convert the +/// TargetFrameIndex into a DirectMemRefOp StackMap location. This avoids +/// address materialization and register allocation, but may also be required +/// for correctness. If a StackMap (or PatchPoint) intrinsic directly uses an +/// alloca in the entry block, then the runtime may assume that the alloca's +/// StackMap location can be read immediately after compilation and that the +/// location is valid at any point during execution (this is similar to the +/// assumption made by the llvm.gcroot intrinsic). If the alloca's location were +/// only available in a register, then the runtime would need to trap when +/// execution reaches the StackMap in order to read the alloca's location. +static void addStackMapLiveVars(ImmutableCallSite CS, unsigned StartIdx, + const SDLoc &DL, SmallVectorImpl<SDValue> &Ops, + SelectionDAGBuilder &Builder) { + for (unsigned i = StartIdx, e = CS.arg_size(); i != e; ++i) { + SDValue OpVal = Builder.getValue(CS.getArgument(i)); + if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(OpVal)) { + Ops.push_back( + Builder.DAG.getTargetConstant(StackMaps::ConstantOp, DL, MVT::i64)); + Ops.push_back( + Builder.DAG.getTargetConstant(C->getSExtValue(), DL, MVT::i64)); + } else if (FrameIndexSDNode *FI = dyn_cast<FrameIndexSDNode>(OpVal)) { + const TargetLowering &TLI = Builder.DAG.getTargetLoweringInfo(); + Ops.push_back(Builder.DAG.getTargetFrameIndex( + FI->getIndex(), TLI.getFrameIndexTy(Builder.DAG.getDataLayout()))); + } else + Ops.push_back(OpVal); + } +} + +/// Lower llvm.experimental.stackmap directly to its target opcode. +void SelectionDAGBuilder::visitStackmap(const CallInst &CI) { + // void @llvm.experimental.stackmap(i32 <id>, i32 <numShadowBytes>, + // [live variables...]) + + assert(CI.getType()->isVoidTy() && "Stackmap cannot return a value."); + + SDValue Chain, InFlag, Callee, NullPtr; + SmallVector<SDValue, 32> Ops; + + SDLoc DL = getCurSDLoc(); + Callee = getValue(CI.getCalledValue()); + NullPtr = DAG.getIntPtrConstant(0, DL, true); + + // The stackmap intrinsic only records the live variables (the arguments + // passed to it) and emits NOPS (if requested). Unlike the patchpoint + // intrinsic, this won't be lowered to a function call. This means we don't + // have to worry about calling conventions and target specific lowering code. + // Instead we perform the call lowering right here. + // + // chain, flag = CALLSEQ_START(chain, 0, 0) + // chain, flag = STACKMAP(id, nbytes, ..., chain, flag) + // chain, flag = CALLSEQ_END(chain, 0, 0, flag) + // + Chain = DAG.getCALLSEQ_START(getRoot(), 0, 0, DL); + InFlag = Chain.getValue(1); + + // Add the <id> and <numBytes> constants. + SDValue IDVal = getValue(CI.getOperand(PatchPointOpers::IDPos)); + Ops.push_back(DAG.getTargetConstant( + cast<ConstantSDNode>(IDVal)->getZExtValue(), DL, MVT::i64)); + SDValue NBytesVal = getValue(CI.getOperand(PatchPointOpers::NBytesPos)); + Ops.push_back(DAG.getTargetConstant( + cast<ConstantSDNode>(NBytesVal)->getZExtValue(), DL, + MVT::i32)); + + // Push live variables for the stack map. + addStackMapLiveVars(&CI, 2, DL, Ops, *this); + + // We are not pushing any register mask info here on the operands list, + // because the stackmap doesn't clobber anything. + + // Push the chain and the glue flag. + Ops.push_back(Chain); + Ops.push_back(InFlag); + + // Create the STACKMAP node. + SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Glue); + SDNode *SM = DAG.getMachineNode(TargetOpcode::STACKMAP, DL, NodeTys, Ops); + Chain = SDValue(SM, 0); + InFlag = Chain.getValue(1); + + Chain = DAG.getCALLSEQ_END(Chain, NullPtr, NullPtr, InFlag, DL); + + // Stackmaps don't generate values, so nothing goes into the NodeMap. + + // Set the root to the target-lowered call chain. + DAG.setRoot(Chain); + + // Inform the Frame Information that we have a stackmap in this function. + FuncInfo.MF->getFrameInfo().setHasStackMap(); +} + +/// Lower llvm.experimental.patchpoint directly to its target opcode. +void SelectionDAGBuilder::visitPatchpoint(ImmutableCallSite CS, + const BasicBlock *EHPadBB) { + // void|i64 @llvm.experimental.patchpoint.void|i64(i64 <id>, + // i32 <numBytes>, + // i8* <target>, + // i32 <numArgs>, + // [Args...], + // [live variables...]) + + CallingConv::ID CC = CS.getCallingConv(); + bool IsAnyRegCC = CC == CallingConv::AnyReg; + bool HasDef = !CS->getType()->isVoidTy(); + SDLoc dl = getCurSDLoc(); + SDValue Callee = getValue(CS->getOperand(PatchPointOpers::TargetPos)); + + // Handle immediate and symbolic callees. + if (auto* ConstCallee = dyn_cast<ConstantSDNode>(Callee)) + Callee = DAG.getIntPtrConstant(ConstCallee->getZExtValue(), dl, + /*isTarget=*/true); + else if (auto* SymbolicCallee = dyn_cast<GlobalAddressSDNode>(Callee)) + Callee = DAG.getTargetGlobalAddress(SymbolicCallee->getGlobal(), + SDLoc(SymbolicCallee), + SymbolicCallee->getValueType(0)); + + // Get the real number of arguments participating in the call <numArgs> + SDValue NArgVal = getValue(CS.getArgument(PatchPointOpers::NArgPos)); + unsigned NumArgs = cast<ConstantSDNode>(NArgVal)->getZExtValue(); + + // Skip the four meta args: <id>, <numNopBytes>, <target>, <numArgs> + // Intrinsics include all meta-operands up to but not including CC. + unsigned NumMetaOpers = PatchPointOpers::CCPos; + assert(CS.arg_size() >= NumMetaOpers + NumArgs && + "Not enough arguments provided to the patchpoint intrinsic"); + + // For AnyRegCC the arguments are lowered later on manually. + unsigned NumCallArgs = IsAnyRegCC ? 0 : NumArgs; + Type *ReturnTy = + IsAnyRegCC ? Type::getVoidTy(*DAG.getContext()) : CS->getType(); + + TargetLowering::CallLoweringInfo CLI(DAG); + populateCallLoweringInfo(CLI, cast<CallBase>(CS.getInstruction()), + NumMetaOpers, NumCallArgs, Callee, ReturnTy, true); + std::pair<SDValue, SDValue> Result = lowerInvokable(CLI, EHPadBB); + + SDNode *CallEnd = Result.second.getNode(); + if (HasDef && (CallEnd->getOpcode() == ISD::CopyFromReg)) + CallEnd = CallEnd->getOperand(0).getNode(); + + /// Get a call instruction from the call sequence chain. + /// Tail calls are not allowed. + assert(CallEnd->getOpcode() == ISD::CALLSEQ_END && + "Expected a callseq node."); + SDNode *Call = CallEnd->getOperand(0).getNode(); + bool HasGlue = Call->getGluedNode(); + + // Replace the target specific call node with the patchable intrinsic. + SmallVector<SDValue, 8> Ops; + + // Add the <id> and <numBytes> constants. + SDValue IDVal = getValue(CS->getOperand(PatchPointOpers::IDPos)); + Ops.push_back(DAG.getTargetConstant( + cast<ConstantSDNode>(IDVal)->getZExtValue(), dl, MVT::i64)); + SDValue NBytesVal = getValue(CS->getOperand(PatchPointOpers::NBytesPos)); + Ops.push_back(DAG.getTargetConstant( + cast<ConstantSDNode>(NBytesVal)->getZExtValue(), dl, + MVT::i32)); + + // Add the callee. + Ops.push_back(Callee); + + // Adjust <numArgs> to account for any arguments that have been passed on the + // stack instead. + // Call Node: Chain, Target, {Args}, RegMask, [Glue] + unsigned NumCallRegArgs = Call->getNumOperands() - (HasGlue ? 4 : 3); + NumCallRegArgs = IsAnyRegCC ? NumArgs : NumCallRegArgs; + Ops.push_back(DAG.getTargetConstant(NumCallRegArgs, dl, MVT::i32)); + + // Add the calling convention + Ops.push_back(DAG.getTargetConstant((unsigned)CC, dl, MVT::i32)); + + // Add the arguments we omitted previously. The register allocator should + // place these in any free register. + if (IsAnyRegCC) + for (unsigned i = NumMetaOpers, e = NumMetaOpers + NumArgs; i != e; ++i) + Ops.push_back(getValue(CS.getArgument(i))); + + // Push the arguments from the call instruction up to the register mask. + SDNode::op_iterator e = HasGlue ? Call->op_end()-2 : Call->op_end()-1; + Ops.append(Call->op_begin() + 2, e); + + // Push live variables for the stack map. + addStackMapLiveVars(CS, NumMetaOpers + NumArgs, dl, Ops, *this); + + // Push the register mask info. + if (HasGlue) + Ops.push_back(*(Call->op_end()-2)); + else + Ops.push_back(*(Call->op_end()-1)); + + // Push the chain (this is originally the first operand of the call, but + // becomes now the last or second to last operand). + Ops.push_back(*(Call->op_begin())); + + // Push the glue flag (last operand). + if (HasGlue) + Ops.push_back(*(Call->op_end()-1)); + + SDVTList NodeTys; + if (IsAnyRegCC && HasDef) { + // Create the return types based on the intrinsic definition + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + SmallVector<EVT, 3> ValueVTs; + ComputeValueVTs(TLI, DAG.getDataLayout(), CS->getType(), ValueVTs); + assert(ValueVTs.size() == 1 && "Expected only one return value type."); + + // There is always a chain and a glue type at the end + ValueVTs.push_back(MVT::Other); + ValueVTs.push_back(MVT::Glue); + NodeTys = DAG.getVTList(ValueVTs); + } else + NodeTys = DAG.getVTList(MVT::Other, MVT::Glue); + + // Replace the target specific call node with a PATCHPOINT node. + MachineSDNode *MN = DAG.getMachineNode(TargetOpcode::PATCHPOINT, + dl, NodeTys, Ops); + + // Update the NodeMap. + if (HasDef) { + if (IsAnyRegCC) + setValue(CS.getInstruction(), SDValue(MN, 0)); + else + setValue(CS.getInstruction(), Result.first); + } + + // Fixup the consumers of the intrinsic. The chain and glue may be used in the + // call sequence. Furthermore the location of the chain and glue can change + // when the AnyReg calling convention is used and the intrinsic returns a + // value. + if (IsAnyRegCC && HasDef) { + SDValue From[] = {SDValue(Call, 0), SDValue(Call, 1)}; + SDValue To[] = {SDValue(MN, 1), SDValue(MN, 2)}; + DAG.ReplaceAllUsesOfValuesWith(From, To, 2); + } else + DAG.ReplaceAllUsesWith(Call, MN); + DAG.DeleteNode(Call); + + // Inform the Frame Information that we have a patchpoint in this function. + FuncInfo.MF->getFrameInfo().setHasPatchPoint(); +} + +void SelectionDAGBuilder::visitVectorReduce(const CallInst &I, + unsigned Intrinsic) { + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + SDValue Op1 = getValue(I.getArgOperand(0)); + SDValue Op2; + if (I.getNumArgOperands() > 1) + Op2 = getValue(I.getArgOperand(1)); + SDLoc dl = getCurSDLoc(); + EVT VT = TLI.getValueType(DAG.getDataLayout(), I.getType()); + SDValue Res; + FastMathFlags FMF; + if (isa<FPMathOperator>(I)) + FMF = I.getFastMathFlags(); + + switch (Intrinsic) { + case Intrinsic::experimental_vector_reduce_v2_fadd: + if (FMF.allowReassoc()) + Res = DAG.getNode(ISD::FADD, dl, VT, Op1, + DAG.getNode(ISD::VECREDUCE_FADD, dl, VT, Op2)); + else + Res = DAG.getNode(ISD::VECREDUCE_STRICT_FADD, dl, VT, Op1, Op2); + break; + case Intrinsic::experimental_vector_reduce_v2_fmul: + if (FMF.allowReassoc()) + Res = DAG.getNode(ISD::FMUL, dl, VT, Op1, + DAG.getNode(ISD::VECREDUCE_FMUL, dl, VT, Op2)); + else + Res = DAG.getNode(ISD::VECREDUCE_STRICT_FMUL, dl, VT, Op1, Op2); + break; + case Intrinsic::experimental_vector_reduce_add: + Res = DAG.getNode(ISD::VECREDUCE_ADD, dl, VT, Op1); + break; + case Intrinsic::experimental_vector_reduce_mul: + Res = DAG.getNode(ISD::VECREDUCE_MUL, dl, VT, Op1); + break; + case Intrinsic::experimental_vector_reduce_and: + Res = DAG.getNode(ISD::VECREDUCE_AND, dl, VT, Op1); + break; + case Intrinsic::experimental_vector_reduce_or: + Res = DAG.getNode(ISD::VECREDUCE_OR, dl, VT, Op1); + break; + case Intrinsic::experimental_vector_reduce_xor: + Res = DAG.getNode(ISD::VECREDUCE_XOR, dl, VT, Op1); + break; + case Intrinsic::experimental_vector_reduce_smax: + Res = DAG.getNode(ISD::VECREDUCE_SMAX, dl, VT, Op1); + break; + case Intrinsic::experimental_vector_reduce_smin: + Res = DAG.getNode(ISD::VECREDUCE_SMIN, dl, VT, Op1); + break; + case Intrinsic::experimental_vector_reduce_umax: + Res = DAG.getNode(ISD::VECREDUCE_UMAX, dl, VT, Op1); + break; + case Intrinsic::experimental_vector_reduce_umin: + Res = DAG.getNode(ISD::VECREDUCE_UMIN, dl, VT, Op1); + break; + case Intrinsic::experimental_vector_reduce_fmax: + Res = DAG.getNode(ISD::VECREDUCE_FMAX, dl, VT, Op1); + break; + case Intrinsic::experimental_vector_reduce_fmin: + Res = DAG.getNode(ISD::VECREDUCE_FMIN, dl, VT, Op1); + break; + default: + llvm_unreachable("Unhandled vector reduce intrinsic"); + } + setValue(&I, Res); +} + +/// Returns an AttributeList representing the attributes applied to the return +/// value of the given call. +static AttributeList getReturnAttrs(TargetLowering::CallLoweringInfo &CLI) { + SmallVector<Attribute::AttrKind, 2> Attrs; + if (CLI.RetSExt) + Attrs.push_back(Attribute::SExt); + if (CLI.RetZExt) + Attrs.push_back(Attribute::ZExt); + if (CLI.IsInReg) + Attrs.push_back(Attribute::InReg); + + return AttributeList::get(CLI.RetTy->getContext(), AttributeList::ReturnIndex, + Attrs); +} + +/// TargetLowering::LowerCallTo - This is the default LowerCallTo +/// implementation, which just calls LowerCall. +/// FIXME: When all targets are +/// migrated to using LowerCall, this hook should be integrated into SDISel. +std::pair<SDValue, SDValue> +TargetLowering::LowerCallTo(TargetLowering::CallLoweringInfo &CLI) const { + // Handle the incoming return values from the call. + CLI.Ins.clear(); + Type *OrigRetTy = CLI.RetTy; + SmallVector<EVT, 4> RetTys; + SmallVector<uint64_t, 4> Offsets; + auto &DL = CLI.DAG.getDataLayout(); + ComputeValueVTs(*this, DL, CLI.RetTy, RetTys, &Offsets); + + if (CLI.IsPostTypeLegalization) { + // If we are lowering a libcall after legalization, split the return type. + SmallVector<EVT, 4> OldRetTys; + SmallVector<uint64_t, 4> OldOffsets; + RetTys.swap(OldRetTys); + Offsets.swap(OldOffsets); + + for (size_t i = 0, e = OldRetTys.size(); i != e; ++i) { + EVT RetVT = OldRetTys[i]; + uint64_t Offset = OldOffsets[i]; + MVT RegisterVT = getRegisterType(CLI.RetTy->getContext(), RetVT); + unsigned NumRegs = getNumRegisters(CLI.RetTy->getContext(), RetVT); + unsigned RegisterVTByteSZ = RegisterVT.getSizeInBits() / 8; + RetTys.append(NumRegs, RegisterVT); + for (unsigned j = 0; j != NumRegs; ++j) + Offsets.push_back(Offset + j * RegisterVTByteSZ); + } + } + + SmallVector<ISD::OutputArg, 4> Outs; + GetReturnInfo(CLI.CallConv, CLI.RetTy, getReturnAttrs(CLI), Outs, *this, DL); + + bool CanLowerReturn = + this->CanLowerReturn(CLI.CallConv, CLI.DAG.getMachineFunction(), + CLI.IsVarArg, Outs, CLI.RetTy->getContext()); + + SDValue DemoteStackSlot; + int DemoteStackIdx = -100; + if (!CanLowerReturn) { + // FIXME: equivalent assert? + // assert(!CS.hasInAllocaArgument() && + // "sret demotion is incompatible with inalloca"); + uint64_t TySize = DL.getTypeAllocSize(CLI.RetTy); + unsigned Align = DL.getPrefTypeAlignment(CLI.RetTy); + MachineFunction &MF = CLI.DAG.getMachineFunction(); + DemoteStackIdx = MF.getFrameInfo().CreateStackObject(TySize, Align, false); + Type *StackSlotPtrType = PointerType::get(CLI.RetTy, + DL.getAllocaAddrSpace()); + + DemoteStackSlot = CLI.DAG.getFrameIndex(DemoteStackIdx, getFrameIndexTy(DL)); + ArgListEntry Entry; + Entry.Node = DemoteStackSlot; + Entry.Ty = StackSlotPtrType; + Entry.IsSExt = false; + Entry.IsZExt = false; + Entry.IsInReg = false; + Entry.IsSRet = true; + Entry.IsNest = false; + Entry.IsByVal = false; + Entry.IsReturned = false; + Entry.IsSwiftSelf = false; + Entry.IsSwiftError = false; + Entry.IsCFGuardTarget = false; + Entry.Alignment = Align; + CLI.getArgs().insert(CLI.getArgs().begin(), Entry); + CLI.NumFixedArgs += 1; + CLI.RetTy = Type::getVoidTy(CLI.RetTy->getContext()); + + // sret demotion isn't compatible with tail-calls, since the sret argument + // points into the callers stack frame. + CLI.IsTailCall = false; + } else { + bool NeedsRegBlock = functionArgumentNeedsConsecutiveRegisters( + CLI.RetTy, CLI.CallConv, CLI.IsVarArg); + for (unsigned I = 0, E = RetTys.size(); I != E; ++I) { + ISD::ArgFlagsTy Flags; + if (NeedsRegBlock) { + Flags.setInConsecutiveRegs(); + if (I == RetTys.size() - 1) + Flags.setInConsecutiveRegsLast(); + } + EVT VT = RetTys[I]; + MVT RegisterVT = getRegisterTypeForCallingConv(CLI.RetTy->getContext(), + CLI.CallConv, VT); + unsigned NumRegs = getNumRegistersForCallingConv(CLI.RetTy->getContext(), + CLI.CallConv, VT); + for (unsigned i = 0; i != NumRegs; ++i) { + ISD::InputArg MyFlags; + MyFlags.Flags = Flags; + MyFlags.VT = RegisterVT; + MyFlags.ArgVT = VT; + MyFlags.Used = CLI.IsReturnValueUsed; + if (CLI.RetTy->isPointerTy()) { + MyFlags.Flags.setPointer(); + MyFlags.Flags.setPointerAddrSpace( + cast<PointerType>(CLI.RetTy)->getAddressSpace()); + } + if (CLI.RetSExt) + MyFlags.Flags.setSExt(); + if (CLI.RetZExt) + MyFlags.Flags.setZExt(); + if (CLI.IsInReg) + MyFlags.Flags.setInReg(); + CLI.Ins.push_back(MyFlags); + } + } + } + + // We push in swifterror return as the last element of CLI.Ins. + ArgListTy &Args = CLI.getArgs(); + if (supportSwiftError()) { + for (unsigned i = 0, e = Args.size(); i != e; ++i) { + if (Args[i].IsSwiftError) { + ISD::InputArg MyFlags; + MyFlags.VT = getPointerTy(DL); + MyFlags.ArgVT = EVT(getPointerTy(DL)); + MyFlags.Flags.setSwiftError(); + CLI.Ins.push_back(MyFlags); + } + } + } + + // Handle all of the outgoing arguments. + CLI.Outs.clear(); + CLI.OutVals.clear(); + for (unsigned i = 0, e = Args.size(); i != e; ++i) { + SmallVector<EVT, 4> ValueVTs; + ComputeValueVTs(*this, DL, Args[i].Ty, ValueVTs); + // FIXME: Split arguments if CLI.IsPostTypeLegalization + Type *FinalType = Args[i].Ty; + if (Args[i].IsByVal) + FinalType = cast<PointerType>(Args[i].Ty)->getElementType(); + bool NeedsRegBlock = functionArgumentNeedsConsecutiveRegisters( + FinalType, CLI.CallConv, CLI.IsVarArg); + for (unsigned Value = 0, NumValues = ValueVTs.size(); Value != NumValues; + ++Value) { + EVT VT = ValueVTs[Value]; + Type *ArgTy = VT.getTypeForEVT(CLI.RetTy->getContext()); + SDValue Op = SDValue(Args[i].Node.getNode(), + Args[i].Node.getResNo() + Value); + ISD::ArgFlagsTy Flags; + + // Certain targets (such as MIPS), may have a different ABI alignment + // for a type depending on the context. Give the target a chance to + // specify the alignment it wants. + const Align OriginalAlignment(getABIAlignmentForCallingConv(ArgTy, DL)); + + if (Args[i].Ty->isPointerTy()) { + Flags.setPointer(); + Flags.setPointerAddrSpace( + cast<PointerType>(Args[i].Ty)->getAddressSpace()); + } + if (Args[i].IsZExt) + Flags.setZExt(); + if (Args[i].IsSExt) + Flags.setSExt(); + if (Args[i].IsInReg) { + // If we are using vectorcall calling convention, a structure that is + // passed InReg - is surely an HVA + if (CLI.CallConv == CallingConv::X86_VectorCall && + isa<StructType>(FinalType)) { + // The first value of a structure is marked + if (0 == Value) + Flags.setHvaStart(); + Flags.setHva(); + } + // Set InReg Flag + Flags.setInReg(); + } + if (Args[i].IsSRet) + Flags.setSRet(); + if (Args[i].IsSwiftSelf) + Flags.setSwiftSelf(); + if (Args[i].IsSwiftError) + Flags.setSwiftError(); + if (Args[i].IsCFGuardTarget) + Flags.setCFGuardTarget(); + if (Args[i].IsByVal) + Flags.setByVal(); + if (Args[i].IsInAlloca) { + Flags.setInAlloca(); + // Set the byval flag for CCAssignFn callbacks that don't know about + // inalloca. This way we can know how many bytes we should've allocated + // and how many bytes a callee cleanup function will pop. If we port + // inalloca to more targets, we'll have to add custom inalloca handling + // in the various CC lowering callbacks. + Flags.setByVal(); + } + if (Args[i].IsByVal || Args[i].IsInAlloca) { + PointerType *Ty = cast<PointerType>(Args[i].Ty); + Type *ElementTy = Ty->getElementType(); + + unsigned FrameSize = DL.getTypeAllocSize( + Args[i].ByValType ? Args[i].ByValType : ElementTy); + Flags.setByValSize(FrameSize); + + // info is not there but there are cases it cannot get right. + unsigned FrameAlign; + if (Args[i].Alignment) + FrameAlign = Args[i].Alignment; + else + FrameAlign = getByValTypeAlignment(ElementTy, DL); + Flags.setByValAlign(Align(FrameAlign)); + } + if (Args[i].IsNest) + Flags.setNest(); + if (NeedsRegBlock) + Flags.setInConsecutiveRegs(); + Flags.setOrigAlign(OriginalAlignment); + + MVT PartVT = getRegisterTypeForCallingConv(CLI.RetTy->getContext(), + CLI.CallConv, VT); + unsigned NumParts = getNumRegistersForCallingConv(CLI.RetTy->getContext(), + CLI.CallConv, VT); + SmallVector<SDValue, 4> Parts(NumParts); + ISD::NodeType ExtendKind = ISD::ANY_EXTEND; + + if (Args[i].IsSExt) + ExtendKind = ISD::SIGN_EXTEND; + else if (Args[i].IsZExt) + ExtendKind = ISD::ZERO_EXTEND; + + // Conservatively only handle 'returned' on non-vectors that can be lowered, + // for now. + if (Args[i].IsReturned && !Op.getValueType().isVector() && + CanLowerReturn) { + assert((CLI.RetTy == Args[i].Ty || + (CLI.RetTy->isPointerTy() && Args[i].Ty->isPointerTy() && + CLI.RetTy->getPointerAddressSpace() == + Args[i].Ty->getPointerAddressSpace())) && + RetTys.size() == NumValues && "unexpected use of 'returned'"); + // Before passing 'returned' to the target lowering code, ensure that + // either the register MVT and the actual EVT are the same size or that + // the return value and argument are extended in the same way; in these + // cases it's safe to pass the argument register value unchanged as the + // return register value (although it's at the target's option whether + // to do so) + // TODO: allow code generation to take advantage of partially preserved + // registers rather than clobbering the entire register when the + // parameter extension method is not compatible with the return + // extension method + if ((NumParts * PartVT.getSizeInBits() == VT.getSizeInBits()) || + (ExtendKind != ISD::ANY_EXTEND && CLI.RetSExt == Args[i].IsSExt && + CLI.RetZExt == Args[i].IsZExt)) + Flags.setReturned(); + } + + getCopyToParts(CLI.DAG, CLI.DL, Op, &Parts[0], NumParts, PartVT, + CLI.CS.getInstruction(), CLI.CallConv, ExtendKind); + + for (unsigned j = 0; j != NumParts; ++j) { + // if it isn't first piece, alignment must be 1 + // For scalable vectors the scalable part is currently handled + // by individual targets, so we just use the known minimum size here. + ISD::OutputArg MyFlags(Flags, Parts[j].getValueType(), VT, + i < CLI.NumFixedArgs, i, + j*Parts[j].getValueType().getStoreSize().getKnownMinSize()); + if (NumParts > 1 && j == 0) + MyFlags.Flags.setSplit(); + else if (j != 0) { + MyFlags.Flags.setOrigAlign(Align::None()); + if (j == NumParts - 1) + MyFlags.Flags.setSplitEnd(); + } + + CLI.Outs.push_back(MyFlags); + CLI.OutVals.push_back(Parts[j]); + } + + if (NeedsRegBlock && Value == NumValues - 1) + CLI.Outs[CLI.Outs.size() - 1].Flags.setInConsecutiveRegsLast(); + } + } + + SmallVector<SDValue, 4> InVals; + CLI.Chain = LowerCall(CLI, InVals); + + // Update CLI.InVals to use outside of this function. + CLI.InVals = InVals; + + // Verify that the target's LowerCall behaved as expected. + assert(CLI.Chain.getNode() && CLI.Chain.getValueType() == MVT::Other && + "LowerCall didn't return a valid chain!"); + assert((!CLI.IsTailCall || InVals.empty()) && + "LowerCall emitted a return value for a tail call!"); + assert((CLI.IsTailCall || InVals.size() == CLI.Ins.size()) && + "LowerCall didn't emit the correct number of values!"); + + // For a tail call, the return value is merely live-out and there aren't + // any nodes in the DAG representing it. Return a special value to + // indicate that a tail call has been emitted and no more Instructions + // should be processed in the current block. + if (CLI.IsTailCall) { + CLI.DAG.setRoot(CLI.Chain); + return std::make_pair(SDValue(), SDValue()); + } + +#ifndef NDEBUG + for (unsigned i = 0, e = CLI.Ins.size(); i != e; ++i) { + assert(InVals[i].getNode() && "LowerCall emitted a null value!"); + assert(EVT(CLI.Ins[i].VT) == InVals[i].getValueType() && + "LowerCall emitted a value with the wrong type!"); + } +#endif + + SmallVector<SDValue, 4> ReturnValues; + if (!CanLowerReturn) { + // The instruction result is the result of loading from the + // hidden sret parameter. + SmallVector<EVT, 1> PVTs; + Type *PtrRetTy = OrigRetTy->getPointerTo(DL.getAllocaAddrSpace()); + + ComputeValueVTs(*this, DL, PtrRetTy, PVTs); + assert(PVTs.size() == 1 && "Pointers should fit in one register"); + EVT PtrVT = PVTs[0]; + + unsigned NumValues = RetTys.size(); + ReturnValues.resize(NumValues); + SmallVector<SDValue, 4> Chains(NumValues); + + // An aggregate return value cannot wrap around the address space, so + // offsets to its parts don't wrap either. + SDNodeFlags Flags; + Flags.setNoUnsignedWrap(true); + + for (unsigned i = 0; i < NumValues; ++i) { + SDValue Add = CLI.DAG.getNode(ISD::ADD, CLI.DL, PtrVT, DemoteStackSlot, + CLI.DAG.getConstant(Offsets[i], CLI.DL, + PtrVT), Flags); + SDValue L = CLI.DAG.getLoad( + RetTys[i], CLI.DL, CLI.Chain, Add, + MachinePointerInfo::getFixedStack(CLI.DAG.getMachineFunction(), + DemoteStackIdx, Offsets[i]), + /* Alignment = */ 1); + ReturnValues[i] = L; + Chains[i] = L.getValue(1); + } + + CLI.Chain = CLI.DAG.getNode(ISD::TokenFactor, CLI.DL, MVT::Other, Chains); + } else { + // Collect the legal value parts into potentially illegal values + // that correspond to the original function's return values. + Optional<ISD::NodeType> AssertOp; + if (CLI.RetSExt) + AssertOp = ISD::AssertSext; + else if (CLI.RetZExt) + AssertOp = ISD::AssertZext; + unsigned CurReg = 0; + for (unsigned I = 0, E = RetTys.size(); I != E; ++I) { + EVT VT = RetTys[I]; + MVT RegisterVT = getRegisterTypeForCallingConv(CLI.RetTy->getContext(), + CLI.CallConv, VT); + unsigned NumRegs = getNumRegistersForCallingConv(CLI.RetTy->getContext(), + CLI.CallConv, VT); + + ReturnValues.push_back(getCopyFromParts(CLI.DAG, CLI.DL, &InVals[CurReg], + NumRegs, RegisterVT, VT, nullptr, + CLI.CallConv, AssertOp)); + CurReg += NumRegs; + } + + // For a function returning void, there is no return value. We can't create + // such a node, so we just return a null return value in that case. In + // that case, nothing will actually look at the value. + if (ReturnValues.empty()) + return std::make_pair(SDValue(), CLI.Chain); + } + + SDValue Res = CLI.DAG.getNode(ISD::MERGE_VALUES, CLI.DL, + CLI.DAG.getVTList(RetTys), ReturnValues); + return std::make_pair(Res, CLI.Chain); +} + +void TargetLowering::LowerOperationWrapper(SDNode *N, + SmallVectorImpl<SDValue> &Results, + SelectionDAG &DAG) const { + if (SDValue Res = LowerOperation(SDValue(N, 0), DAG)) + Results.push_back(Res); +} + +SDValue TargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) const { + llvm_unreachable("LowerOperation not implemented for this target!"); +} + +void +SelectionDAGBuilder::CopyValueToVirtualRegister(const Value *V, unsigned Reg) { + SDValue Op = getNonRegisterValue(V); + assert((Op.getOpcode() != ISD::CopyFromReg || + cast<RegisterSDNode>(Op.getOperand(1))->getReg() != Reg) && + "Copy from a reg to the same reg!"); + assert(!Register::isPhysicalRegister(Reg) && "Is a physreg"); + + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + // If this is an InlineAsm we have to match the registers required, not the + // notional registers required by the type. + + RegsForValue RFV(V->getContext(), TLI, DAG.getDataLayout(), Reg, V->getType(), + None); // This is not an ABI copy. + SDValue Chain = DAG.getEntryNode(); + + ISD::NodeType ExtendType = (FuncInfo.PreferredExtendType.find(V) == + FuncInfo.PreferredExtendType.end()) + ? ISD::ANY_EXTEND + : FuncInfo.PreferredExtendType[V]; + RFV.getCopyToRegs(Op, DAG, getCurSDLoc(), Chain, nullptr, V, ExtendType); + PendingExports.push_back(Chain); +} + +#include "llvm/CodeGen/SelectionDAGISel.h" + +/// isOnlyUsedInEntryBlock - If the specified argument is only used in the +/// entry block, return true. This includes arguments used by switches, since +/// the switch may expand into multiple basic blocks. +static bool isOnlyUsedInEntryBlock(const Argument *A, bool FastISel) { + // With FastISel active, we may be splitting blocks, so force creation + // of virtual registers for all non-dead arguments. + if (FastISel) + return A->use_empty(); + + const BasicBlock &Entry = A->getParent()->front(); + for (const User *U : A->users()) + if (cast<Instruction>(U)->getParent() != &Entry || isa<SwitchInst>(U)) + return false; // Use not in entry block. + + return true; +} + +using ArgCopyElisionMapTy = + DenseMap<const Argument *, + std::pair<const AllocaInst *, const StoreInst *>>; + +/// Scan the entry block of the function in FuncInfo for arguments that look +/// like copies into a local alloca. Record any copied arguments in +/// ArgCopyElisionCandidates. +static void +findArgumentCopyElisionCandidates(const DataLayout &DL, + FunctionLoweringInfo *FuncInfo, + ArgCopyElisionMapTy &ArgCopyElisionCandidates) { + // Record the state of every static alloca used in the entry block. Argument + // allocas are all used in the entry block, so we need approximately as many + // entries as we have arguments. + enum StaticAllocaInfo { Unknown, Clobbered, Elidable }; + SmallDenseMap<const AllocaInst *, StaticAllocaInfo, 8> StaticAllocas; + unsigned NumArgs = FuncInfo->Fn->arg_size(); + StaticAllocas.reserve(NumArgs * 2); + + auto GetInfoIfStaticAlloca = [&](const Value *V) -> StaticAllocaInfo * { + if (!V) + return nullptr; + V = V->stripPointerCasts(); + const auto *AI = dyn_cast<AllocaInst>(V); + if (!AI || !AI->isStaticAlloca() || !FuncInfo->StaticAllocaMap.count(AI)) + return nullptr; + auto Iter = StaticAllocas.insert({AI, Unknown}); + return &Iter.first->second; + }; + + // Look for stores of arguments to static allocas. Look through bitcasts and + // GEPs to handle type coercions, as long as the alloca is fully initialized + // by the store. Any non-store use of an alloca escapes it and any subsequent + // unanalyzed store might write it. + // FIXME: Handle structs initialized with multiple stores. + for (const Instruction &I : FuncInfo->Fn->getEntryBlock()) { + // Look for stores, and handle non-store uses conservatively. + const auto *SI = dyn_cast<StoreInst>(&I); + if (!SI) { + // We will look through cast uses, so ignore them completely. + if (I.isCast()) + continue; + // Ignore debug info intrinsics, they don't escape or store to allocas. + if (isa<DbgInfoIntrinsic>(I)) + continue; + // This is an unknown instruction. Assume it escapes or writes to all + // static alloca operands. + for (const Use &U : I.operands()) { + if (StaticAllocaInfo *Info = GetInfoIfStaticAlloca(U)) + *Info = StaticAllocaInfo::Clobbered; + } + continue; + } + + // If the stored value is a static alloca, mark it as escaped. + if (StaticAllocaInfo *Info = GetInfoIfStaticAlloca(SI->getValueOperand())) + *Info = StaticAllocaInfo::Clobbered; + + // Check if the destination is a static alloca. + const Value *Dst = SI->getPointerOperand()->stripPointerCasts(); + StaticAllocaInfo *Info = GetInfoIfStaticAlloca(Dst); + if (!Info) + continue; + const AllocaInst *AI = cast<AllocaInst>(Dst); + + // Skip allocas that have been initialized or clobbered. + if (*Info != StaticAllocaInfo::Unknown) + continue; + + // Check if the stored value is an argument, and that this store fully + // initializes the alloca. Don't elide copies from the same argument twice. + const Value *Val = SI->getValueOperand()->stripPointerCasts(); + const auto *Arg = dyn_cast<Argument>(Val); + if (!Arg || Arg->hasInAllocaAttr() || Arg->hasByValAttr() || + Arg->getType()->isEmptyTy() || + DL.getTypeStoreSize(Arg->getType()) != + DL.getTypeAllocSize(AI->getAllocatedType()) || + ArgCopyElisionCandidates.count(Arg)) { + *Info = StaticAllocaInfo::Clobbered; + continue; + } + + LLVM_DEBUG(dbgs() << "Found argument copy elision candidate: " << *AI + << '\n'); + + // Mark this alloca and store for argument copy elision. + *Info = StaticAllocaInfo::Elidable; + ArgCopyElisionCandidates.insert({Arg, {AI, SI}}); + + // Stop scanning if we've seen all arguments. This will happen early in -O0 + // builds, which is useful, because -O0 builds have large entry blocks and + // many allocas. + if (ArgCopyElisionCandidates.size() == NumArgs) + break; + } +} + +/// Try to elide argument copies from memory into a local alloca. Succeeds if +/// ArgVal is a load from a suitable fixed stack object. +static void tryToElideArgumentCopy( + FunctionLoweringInfo &FuncInfo, SmallVectorImpl<SDValue> &Chains, + DenseMap<int, int> &ArgCopyElisionFrameIndexMap, + SmallPtrSetImpl<const Instruction *> &ElidedArgCopyInstrs, + ArgCopyElisionMapTy &ArgCopyElisionCandidates, const Argument &Arg, + SDValue ArgVal, bool &ArgHasUses) { + // Check if this is a load from a fixed stack object. + auto *LNode = dyn_cast<LoadSDNode>(ArgVal); + if (!LNode) + return; + auto *FINode = dyn_cast<FrameIndexSDNode>(LNode->getBasePtr().getNode()); + if (!FINode) + return; + + // Check that the fixed stack object is the right size and alignment. + // Look at the alignment that the user wrote on the alloca instead of looking + // at the stack object. + auto ArgCopyIter = ArgCopyElisionCandidates.find(&Arg); + assert(ArgCopyIter != ArgCopyElisionCandidates.end()); + const AllocaInst *AI = ArgCopyIter->second.first; + int FixedIndex = FINode->getIndex(); + int &AllocaIndex = FuncInfo.StaticAllocaMap[AI]; + int OldIndex = AllocaIndex; + MachineFrameInfo &MFI = FuncInfo.MF->getFrameInfo(); + if (MFI.getObjectSize(FixedIndex) != MFI.getObjectSize(OldIndex)) { + LLVM_DEBUG( + dbgs() << " argument copy elision failed due to bad fixed stack " + "object size\n"); + return; + } + unsigned RequiredAlignment = AI->getAlignment(); + if (!RequiredAlignment) { + RequiredAlignment = FuncInfo.MF->getDataLayout().getABITypeAlignment( + AI->getAllocatedType()); + } + if (MFI.getObjectAlignment(FixedIndex) < RequiredAlignment) { + LLVM_DEBUG(dbgs() << " argument copy elision failed: alignment of alloca " + "greater than stack argument alignment (" + << RequiredAlignment << " vs " + << MFI.getObjectAlignment(FixedIndex) << ")\n"); + return; + } + + // Perform the elision. Delete the old stack object and replace its only use + // in the variable info map. Mark the stack object as mutable. + LLVM_DEBUG({ + dbgs() << "Eliding argument copy from " << Arg << " to " << *AI << '\n' + << " Replacing frame index " << OldIndex << " with " << FixedIndex + << '\n'; + }); + MFI.RemoveStackObject(OldIndex); + MFI.setIsImmutableObjectIndex(FixedIndex, false); + AllocaIndex = FixedIndex; + ArgCopyElisionFrameIndexMap.insert({OldIndex, FixedIndex}); + Chains.push_back(ArgVal.getValue(1)); + + // Avoid emitting code for the store implementing the copy. + const StoreInst *SI = ArgCopyIter->second.second; + ElidedArgCopyInstrs.insert(SI); + + // Check for uses of the argument again so that we can avoid exporting ArgVal + // if it is't used by anything other than the store. + for (const Value *U : Arg.users()) { + if (U != SI) { + ArgHasUses = true; + break; + } + } +} + +void SelectionDAGISel::LowerArguments(const Function &F) { + SelectionDAG &DAG = SDB->DAG; + SDLoc dl = SDB->getCurSDLoc(); + const DataLayout &DL = DAG.getDataLayout(); + SmallVector<ISD::InputArg, 16> Ins; + + if (!FuncInfo->CanLowerReturn) { + // Put in an sret pointer parameter before all the other parameters. + SmallVector<EVT, 1> ValueVTs; + ComputeValueVTs(*TLI, DAG.getDataLayout(), + F.getReturnType()->getPointerTo( + DAG.getDataLayout().getAllocaAddrSpace()), + ValueVTs); + + // NOTE: Assuming that a pointer will never break down to more than one VT + // or one register. + ISD::ArgFlagsTy Flags; + Flags.setSRet(); + MVT RegisterVT = TLI->getRegisterType(*DAG.getContext(), ValueVTs[0]); + ISD::InputArg RetArg(Flags, RegisterVT, ValueVTs[0], true, + ISD::InputArg::NoArgIndex, 0); + Ins.push_back(RetArg); + } + + // Look for stores of arguments to static allocas. Mark such arguments with a + // flag to ask the target to give us the memory location of that argument if + // available. + ArgCopyElisionMapTy ArgCopyElisionCandidates; + findArgumentCopyElisionCandidates(DL, FuncInfo.get(), + ArgCopyElisionCandidates); + + // Set up the incoming argument description vector. + for (const Argument &Arg : F.args()) { + unsigned ArgNo = Arg.getArgNo(); + SmallVector<EVT, 4> ValueVTs; + ComputeValueVTs(*TLI, DAG.getDataLayout(), Arg.getType(), ValueVTs); + bool isArgValueUsed = !Arg.use_empty(); + unsigned PartBase = 0; + Type *FinalType = Arg.getType(); + if (Arg.hasAttribute(Attribute::ByVal)) + FinalType = Arg.getParamByValType(); + bool NeedsRegBlock = TLI->functionArgumentNeedsConsecutiveRegisters( + FinalType, F.getCallingConv(), F.isVarArg()); + for (unsigned Value = 0, NumValues = ValueVTs.size(); + Value != NumValues; ++Value) { + EVT VT = ValueVTs[Value]; + Type *ArgTy = VT.getTypeForEVT(*DAG.getContext()); + ISD::ArgFlagsTy Flags; + + // Certain targets (such as MIPS), may have a different ABI alignment + // for a type depending on the context. Give the target a chance to + // specify the alignment it wants. + const Align OriginalAlignment( + TLI->getABIAlignmentForCallingConv(ArgTy, DL)); + + if (Arg.getType()->isPointerTy()) { + Flags.setPointer(); + Flags.setPointerAddrSpace( + cast<PointerType>(Arg.getType())->getAddressSpace()); + } + if (Arg.hasAttribute(Attribute::ZExt)) + Flags.setZExt(); + if (Arg.hasAttribute(Attribute::SExt)) + Flags.setSExt(); + if (Arg.hasAttribute(Attribute::InReg)) { + // If we are using vectorcall calling convention, a structure that is + // passed InReg - is surely an HVA + if (F.getCallingConv() == CallingConv::X86_VectorCall && + isa<StructType>(Arg.getType())) { + // The first value of a structure is marked + if (0 == Value) + Flags.setHvaStart(); + Flags.setHva(); + } + // Set InReg Flag + Flags.setInReg(); + } + if (Arg.hasAttribute(Attribute::StructRet)) + Flags.setSRet(); + if (Arg.hasAttribute(Attribute::SwiftSelf)) + Flags.setSwiftSelf(); + if (Arg.hasAttribute(Attribute::SwiftError)) + Flags.setSwiftError(); + if (Arg.hasAttribute(Attribute::ByVal)) + Flags.setByVal(); + if (Arg.hasAttribute(Attribute::InAlloca)) { + Flags.setInAlloca(); + // Set the byval flag for CCAssignFn callbacks that don't know about + // inalloca. This way we can know how many bytes we should've allocated + // and how many bytes a callee cleanup function will pop. If we port + // inalloca to more targets, we'll have to add custom inalloca handling + // in the various CC lowering callbacks. + Flags.setByVal(); + } + if (F.getCallingConv() == CallingConv::X86_INTR) { + // IA Interrupt passes frame (1st parameter) by value in the stack. + if (ArgNo == 0) + Flags.setByVal(); + } + if (Flags.isByVal() || Flags.isInAlloca()) { + Type *ElementTy = Arg.getParamByValType(); + + // For ByVal, size and alignment should be passed from FE. BE will + // guess if this info is not there but there are cases it cannot get + // right. + unsigned FrameSize = DL.getTypeAllocSize(Arg.getParamByValType()); + Flags.setByValSize(FrameSize); + + unsigned FrameAlign; + if (Arg.getParamAlignment()) + FrameAlign = Arg.getParamAlignment(); + else + FrameAlign = TLI->getByValTypeAlignment(ElementTy, DL); + Flags.setByValAlign(Align(FrameAlign)); + } + if (Arg.hasAttribute(Attribute::Nest)) + Flags.setNest(); + if (NeedsRegBlock) + Flags.setInConsecutiveRegs(); + Flags.setOrigAlign(OriginalAlignment); + if (ArgCopyElisionCandidates.count(&Arg)) + Flags.setCopyElisionCandidate(); + if (Arg.hasAttribute(Attribute::Returned)) + Flags.setReturned(); + + MVT RegisterVT = TLI->getRegisterTypeForCallingConv( + *CurDAG->getContext(), F.getCallingConv(), VT); + unsigned NumRegs = TLI->getNumRegistersForCallingConv( + *CurDAG->getContext(), F.getCallingConv(), VT); + for (unsigned i = 0; i != NumRegs; ++i) { + // For scalable vectors, use the minimum size; individual targets + // are responsible for handling scalable vector arguments and + // return values. + ISD::InputArg MyFlags(Flags, RegisterVT, VT, isArgValueUsed, + ArgNo, PartBase+i*RegisterVT.getStoreSize().getKnownMinSize()); + if (NumRegs > 1 && i == 0) + MyFlags.Flags.setSplit(); + // if it isn't first piece, alignment must be 1 + else if (i > 0) { + MyFlags.Flags.setOrigAlign(Align::None()); + if (i == NumRegs - 1) + MyFlags.Flags.setSplitEnd(); + } + Ins.push_back(MyFlags); + } + if (NeedsRegBlock && Value == NumValues - 1) + Ins[Ins.size() - 1].Flags.setInConsecutiveRegsLast(); + PartBase += VT.getStoreSize().getKnownMinSize(); + } + } + + // Call the target to set up the argument values. + SmallVector<SDValue, 8> InVals; + SDValue NewRoot = TLI->LowerFormalArguments( + DAG.getRoot(), F.getCallingConv(), F.isVarArg(), Ins, dl, DAG, InVals); + + // Verify that the target's LowerFormalArguments behaved as expected. + assert(NewRoot.getNode() && NewRoot.getValueType() == MVT::Other && + "LowerFormalArguments didn't return a valid chain!"); + assert(InVals.size() == Ins.size() && + "LowerFormalArguments didn't emit the correct number of values!"); + LLVM_DEBUG({ + for (unsigned i = 0, e = Ins.size(); i != e; ++i) { + assert(InVals[i].getNode() && + "LowerFormalArguments emitted a null value!"); + assert(EVT(Ins[i].VT) == InVals[i].getValueType() && + "LowerFormalArguments emitted a value with the wrong type!"); + } + }); + + // Update the DAG with the new chain value resulting from argument lowering. + DAG.setRoot(NewRoot); + + // Set up the argument values. + unsigned i = 0; + if (!FuncInfo->CanLowerReturn) { + // Create a virtual register for the sret pointer, and put in a copy + // from the sret argument into it. + SmallVector<EVT, 1> ValueVTs; + ComputeValueVTs(*TLI, DAG.getDataLayout(), + F.getReturnType()->getPointerTo( + DAG.getDataLayout().getAllocaAddrSpace()), + ValueVTs); + MVT VT = ValueVTs[0].getSimpleVT(); + MVT RegVT = TLI->getRegisterType(*CurDAG->getContext(), VT); + Optional<ISD::NodeType> AssertOp = None; + SDValue ArgValue = getCopyFromParts(DAG, dl, &InVals[0], 1, RegVT, VT, + nullptr, F.getCallingConv(), AssertOp); + + MachineFunction& MF = SDB->DAG.getMachineFunction(); + MachineRegisterInfo& RegInfo = MF.getRegInfo(); + Register SRetReg = + RegInfo.createVirtualRegister(TLI->getRegClassFor(RegVT)); + FuncInfo->DemoteRegister = SRetReg; + NewRoot = + SDB->DAG.getCopyToReg(NewRoot, SDB->getCurSDLoc(), SRetReg, ArgValue); + DAG.setRoot(NewRoot); + + // i indexes lowered arguments. Bump it past the hidden sret argument. + ++i; + } + + SmallVector<SDValue, 4> Chains; + DenseMap<int, int> ArgCopyElisionFrameIndexMap; + for (const Argument &Arg : F.args()) { + SmallVector<SDValue, 4> ArgValues; + SmallVector<EVT, 4> ValueVTs; + ComputeValueVTs(*TLI, DAG.getDataLayout(), Arg.getType(), ValueVTs); + unsigned NumValues = ValueVTs.size(); + if (NumValues == 0) + continue; + + bool ArgHasUses = !Arg.use_empty(); + + // Elide the copying store if the target loaded this argument from a + // suitable fixed stack object. + if (Ins[i].Flags.isCopyElisionCandidate()) { + tryToElideArgumentCopy(*FuncInfo, Chains, ArgCopyElisionFrameIndexMap, + ElidedArgCopyInstrs, ArgCopyElisionCandidates, Arg, + InVals[i], ArgHasUses); + } + + // If this argument is unused then remember its value. It is used to generate + // debugging information. + bool isSwiftErrorArg = + TLI->supportSwiftError() && + Arg.hasAttribute(Attribute::SwiftError); + if (!ArgHasUses && !isSwiftErrorArg) { + SDB->setUnusedArgValue(&Arg, InVals[i]); + + // Also remember any frame index for use in FastISel. + if (FrameIndexSDNode *FI = + dyn_cast<FrameIndexSDNode>(InVals[i].getNode())) + FuncInfo->setArgumentFrameIndex(&Arg, FI->getIndex()); + } + + for (unsigned Val = 0; Val != NumValues; ++Val) { + EVT VT = ValueVTs[Val]; + MVT PartVT = TLI->getRegisterTypeForCallingConv(*CurDAG->getContext(), + F.getCallingConv(), VT); + unsigned NumParts = TLI->getNumRegistersForCallingConv( + *CurDAG->getContext(), F.getCallingConv(), VT); + + // Even an apparent 'unused' swifterror argument needs to be returned. So + // we do generate a copy for it that can be used on return from the + // function. + if (ArgHasUses || isSwiftErrorArg) { + Optional<ISD::NodeType> AssertOp; + if (Arg.hasAttribute(Attribute::SExt)) + AssertOp = ISD::AssertSext; + else if (Arg.hasAttribute(Attribute::ZExt)) + AssertOp = ISD::AssertZext; + + ArgValues.push_back(getCopyFromParts(DAG, dl, &InVals[i], NumParts, + PartVT, VT, nullptr, + F.getCallingConv(), AssertOp)); + } + + i += NumParts; + } + + // We don't need to do anything else for unused arguments. + if (ArgValues.empty()) + continue; + + // Note down frame index. + if (FrameIndexSDNode *FI = + dyn_cast<FrameIndexSDNode>(ArgValues[0].getNode())) + FuncInfo->setArgumentFrameIndex(&Arg, FI->getIndex()); + + SDValue Res = DAG.getMergeValues(makeArrayRef(ArgValues.data(), NumValues), + SDB->getCurSDLoc()); + + SDB->setValue(&Arg, Res); + if (!TM.Options.EnableFastISel && Res.getOpcode() == ISD::BUILD_PAIR) { + // We want to associate the argument with the frame index, among + // involved operands, that correspond to the lowest address. The + // getCopyFromParts function, called earlier, is swapping the order of + // the operands to BUILD_PAIR depending on endianness. The result of + // that swapping is that the least significant bits of the argument will + // be in the first operand of the BUILD_PAIR node, and the most + // significant bits will be in the second operand. + unsigned LowAddressOp = DAG.getDataLayout().isBigEndian() ? 1 : 0; + if (LoadSDNode *LNode = + dyn_cast<LoadSDNode>(Res.getOperand(LowAddressOp).getNode())) + if (FrameIndexSDNode *FI = + dyn_cast<FrameIndexSDNode>(LNode->getBasePtr().getNode())) + FuncInfo->setArgumentFrameIndex(&Arg, FI->getIndex()); + } + + // Analyses past this point are naive and don't expect an assertion. + if (Res.getOpcode() == ISD::AssertZext) + Res = Res.getOperand(0); + + // Update the SwiftErrorVRegDefMap. + if (Res.getOpcode() == ISD::CopyFromReg && isSwiftErrorArg) { + unsigned Reg = cast<RegisterSDNode>(Res.getOperand(1))->getReg(); + if (Register::isVirtualRegister(Reg)) + SwiftError->setCurrentVReg(FuncInfo->MBB, SwiftError->getFunctionArg(), + Reg); + } + + // If this argument is live outside of the entry block, insert a copy from + // wherever we got it to the vreg that other BB's will reference it as. + if (Res.getOpcode() == ISD::CopyFromReg) { + // If we can, though, try to skip creating an unnecessary vreg. + // FIXME: This isn't very clean... it would be nice to make this more + // general. + unsigned Reg = cast<RegisterSDNode>(Res.getOperand(1))->getReg(); + if (Register::isVirtualRegister(Reg)) { + FuncInfo->ValueMap[&Arg] = Reg; + continue; + } + } + if (!isOnlyUsedInEntryBlock(&Arg, TM.Options.EnableFastISel)) { + FuncInfo->InitializeRegForValue(&Arg); + SDB->CopyToExportRegsIfNeeded(&Arg); + } + } + + if (!Chains.empty()) { + Chains.push_back(NewRoot); + NewRoot = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Chains); + } + + DAG.setRoot(NewRoot); + + assert(i == InVals.size() && "Argument register count mismatch!"); + + // If any argument copy elisions occurred and we have debug info, update the + // stale frame indices used in the dbg.declare variable info table. + MachineFunction::VariableDbgInfoMapTy &DbgDeclareInfo = MF->getVariableDbgInfo(); + if (!DbgDeclareInfo.empty() && !ArgCopyElisionFrameIndexMap.empty()) { + for (MachineFunction::VariableDbgInfo &VI : DbgDeclareInfo) { + auto I = ArgCopyElisionFrameIndexMap.find(VI.Slot); + if (I != ArgCopyElisionFrameIndexMap.end()) + VI.Slot = I->second; + } + } + + // Finally, if the target has anything special to do, allow it to do so. + EmitFunctionEntryCode(); +} + +/// Handle PHI nodes in successor blocks. Emit code into the SelectionDAG to +/// ensure constants are generated when needed. Remember the virtual registers +/// that need to be added to the Machine PHI nodes as input. We cannot just +/// directly add them, because expansion might result in multiple MBB's for one +/// BB. As such, the start of the BB might correspond to a different MBB than +/// the end. +void +SelectionDAGBuilder::HandlePHINodesInSuccessorBlocks(const BasicBlock *LLVMBB) { + const Instruction *TI = LLVMBB->getTerminator(); + + SmallPtrSet<MachineBasicBlock *, 4> SuccsHandled; + + // Check PHI nodes in successors that expect a value to be available from this + // block. + for (unsigned succ = 0, e = TI->getNumSuccessors(); succ != e; ++succ) { + const BasicBlock *SuccBB = TI->getSuccessor(succ); + if (!isa<PHINode>(SuccBB->begin())) continue; + MachineBasicBlock *SuccMBB = FuncInfo.MBBMap[SuccBB]; + + // If this terminator has multiple identical successors (common for + // switches), only handle each succ once. + if (!SuccsHandled.insert(SuccMBB).second) + continue; + + MachineBasicBlock::iterator MBBI = SuccMBB->begin(); + + // At this point we know that there is a 1-1 correspondence between LLVM PHI + // nodes and Machine PHI nodes, but the incoming operands have not been + // emitted yet. + for (const PHINode &PN : SuccBB->phis()) { + // Ignore dead phi's. + if (PN.use_empty()) + continue; + + // Skip empty types + if (PN.getType()->isEmptyTy()) + continue; + + unsigned Reg; + const Value *PHIOp = PN.getIncomingValueForBlock(LLVMBB); + + if (const Constant *C = dyn_cast<Constant>(PHIOp)) { + unsigned &RegOut = ConstantsOut[C]; + if (RegOut == 0) { + RegOut = FuncInfo.CreateRegs(C); + CopyValueToVirtualRegister(C, RegOut); + } + Reg = RegOut; + } else { + DenseMap<const Value *, unsigned>::iterator I = + FuncInfo.ValueMap.find(PHIOp); + if (I != FuncInfo.ValueMap.end()) + Reg = I->second; + else { + assert(isa<AllocaInst>(PHIOp) && + FuncInfo.StaticAllocaMap.count(cast<AllocaInst>(PHIOp)) && + "Didn't codegen value into a register!??"); + Reg = FuncInfo.CreateRegs(PHIOp); + CopyValueToVirtualRegister(PHIOp, Reg); + } + } + + // Remember that this register needs to added to the machine PHI node as + // the input for this MBB. + SmallVector<EVT, 4> ValueVTs; + const TargetLowering &TLI = DAG.getTargetLoweringInfo(); + ComputeValueVTs(TLI, DAG.getDataLayout(), PN.getType(), ValueVTs); + for (unsigned vti = 0, vte = ValueVTs.size(); vti != vte; ++vti) { + EVT VT = ValueVTs[vti]; + unsigned NumRegisters = TLI.getNumRegisters(*DAG.getContext(), VT); + for (unsigned i = 0, e = NumRegisters; i != e; ++i) + FuncInfo.PHINodesToUpdate.push_back( + std::make_pair(&*MBBI++, Reg + i)); + Reg += NumRegisters; + } + } + } + + ConstantsOut.clear(); +} + +/// Add a successor MBB to ParentMBB< creating a new MachineBB for BB if SuccMBB +/// is 0. +MachineBasicBlock * +SelectionDAGBuilder::StackProtectorDescriptor:: +AddSuccessorMBB(const BasicBlock *BB, + MachineBasicBlock *ParentMBB, + bool IsLikely, + MachineBasicBlock *SuccMBB) { + // If SuccBB has not been created yet, create it. + if (!SuccMBB) { + MachineFunction *MF = ParentMBB->getParent(); + MachineFunction::iterator BBI(ParentMBB); + SuccMBB = MF->CreateMachineBasicBlock(BB); + MF->insert(++BBI, SuccMBB); + } + // Add it as a successor of ParentMBB. + ParentMBB->addSuccessor( + SuccMBB, BranchProbabilityInfo::getBranchProbStackProtector(IsLikely)); + return SuccMBB; +} + +MachineBasicBlock *SelectionDAGBuilder::NextBlock(MachineBasicBlock *MBB) { + MachineFunction::iterator I(MBB); + if (++I == FuncInfo.MF->end()) + return nullptr; + return &*I; +} + +/// During lowering new call nodes can be created (such as memset, etc.). +/// Those will become new roots of the current DAG, but complications arise +/// when they are tail calls. In such cases, the call lowering will update +/// the root, but the builder still needs to know that a tail call has been +/// lowered in order to avoid generating an additional return. +void SelectionDAGBuilder::updateDAGForMaybeTailCall(SDValue MaybeTC) { + // If the node is null, we do have a tail call. + if (MaybeTC.getNode() != nullptr) + DAG.setRoot(MaybeTC); + else + HasTailCall = true; +} + +void SelectionDAGBuilder::lowerWorkItem(SwitchWorkListItem W, Value *Cond, + MachineBasicBlock *SwitchMBB, + MachineBasicBlock *DefaultMBB) { + MachineFunction *CurMF = FuncInfo.MF; + MachineBasicBlock *NextMBB = nullptr; + MachineFunction::iterator BBI(W.MBB); + if (++BBI != FuncInfo.MF->end()) + NextMBB = &*BBI; + + unsigned Size = W.LastCluster - W.FirstCluster + 1; + + BranchProbabilityInfo *BPI = FuncInfo.BPI; + + if (Size == 2 && W.MBB == SwitchMBB) { + // If any two of the cases has the same destination, and if one value + // is the same as the other, but has one bit unset that the other has set, + // use bit manipulation to do two compares at once. For example: + // "if (X == 6 || X == 4)" -> "if ((X|2) == 6)" + // TODO: This could be extended to merge any 2 cases in switches with 3 + // cases. + // TODO: Handle cases where W.CaseBB != SwitchBB. + CaseCluster &Small = *W.FirstCluster; + CaseCluster &Big = *W.LastCluster; + + if (Small.Low == Small.High && Big.Low == Big.High && + Small.MBB == Big.MBB) { + const APInt &SmallValue = Small.Low->getValue(); + const APInt &BigValue = Big.Low->getValue(); + + // Check that there is only one bit different. + APInt CommonBit = BigValue ^ SmallValue; + if (CommonBit.isPowerOf2()) { + SDValue CondLHS = getValue(Cond); + EVT VT = CondLHS.getValueType(); + SDLoc DL = getCurSDLoc(); + + SDValue Or = DAG.getNode(ISD::OR, DL, VT, CondLHS, + DAG.getConstant(CommonBit, DL, VT)); + SDValue Cond = DAG.getSetCC( + DL, MVT::i1, Or, DAG.getConstant(BigValue | SmallValue, DL, VT), + ISD::SETEQ); + + // Update successor info. + // Both Small and Big will jump to Small.BB, so we sum up the + // probabilities. + addSuccessorWithProb(SwitchMBB, Small.MBB, Small.Prob + Big.Prob); + if (BPI) + addSuccessorWithProb( + SwitchMBB, DefaultMBB, + // The default destination is the first successor in IR. + BPI->getEdgeProbability(SwitchMBB->getBasicBlock(), (unsigned)0)); + else + addSuccessorWithProb(SwitchMBB, DefaultMBB); + + // Insert the true branch. + SDValue BrCond = + DAG.getNode(ISD::BRCOND, DL, MVT::Other, getControlRoot(), Cond, + DAG.getBasicBlock(Small.MBB)); + // Insert the false branch. + BrCond = DAG.getNode(ISD::BR, DL, MVT::Other, BrCond, + DAG.getBasicBlock(DefaultMBB)); + + DAG.setRoot(BrCond); + return; + } + } + } + + if (TM.getOptLevel() != CodeGenOpt::None) { + // Here, we order cases by probability so the most likely case will be + // checked first. However, two clusters can have the same probability in + // which case their relative ordering is non-deterministic. So we use Low + // as a tie-breaker as clusters are guaranteed to never overlap. + llvm::sort(W.FirstCluster, W.LastCluster + 1, + [](const CaseCluster &a, const CaseCluster &b) { + return a.Prob != b.Prob ? + a.Prob > b.Prob : + a.Low->getValue().slt(b.Low->getValue()); + }); + + // Rearrange the case blocks so that the last one falls through if possible + // without changing the order of probabilities. + for (CaseClusterIt I = W.LastCluster; I > W.FirstCluster; ) { + --I; + if (I->Prob > W.LastCluster->Prob) + break; + if (I->Kind == CC_Range && I->MBB == NextMBB) { + std::swap(*I, *W.LastCluster); + break; + } + } + } + + // Compute total probability. + BranchProbability DefaultProb = W.DefaultProb; + BranchProbability UnhandledProbs = DefaultProb; + for (CaseClusterIt I = W.FirstCluster; I <= W.LastCluster; ++I) + UnhandledProbs += I->Prob; + + MachineBasicBlock *CurMBB = W.MBB; + for (CaseClusterIt I = W.FirstCluster, E = W.LastCluster; I <= E; ++I) { + bool FallthroughUnreachable = false; + MachineBasicBlock *Fallthrough; + if (I == W.LastCluster) { + // For the last cluster, fall through to the default destination. + Fallthrough = DefaultMBB; + FallthroughUnreachable = isa<UnreachableInst>( + DefaultMBB->getBasicBlock()->getFirstNonPHIOrDbg()); + } else { + Fallthrough = CurMF->CreateMachineBasicBlock(CurMBB->getBasicBlock()); + CurMF->insert(BBI, Fallthrough); + // Put Cond in a virtual register to make it available from the new blocks. + ExportFromCurrentBlock(Cond); + } + UnhandledProbs -= I->Prob; + + switch (I->Kind) { + case CC_JumpTable: { + // FIXME: Optimize away range check based on pivot comparisons. + JumpTableHeader *JTH = &SL->JTCases[I->JTCasesIndex].first; + SwitchCG::JumpTable *JT = &SL->JTCases[I->JTCasesIndex].second; + + // The jump block hasn't been inserted yet; insert it here. + MachineBasicBlock *JumpMBB = JT->MBB; + CurMF->insert(BBI, JumpMBB); + + auto JumpProb = I->Prob; + auto FallthroughProb = UnhandledProbs; + + // If the default statement is a target of the jump table, we evenly + // distribute the default probability to successors of CurMBB. Also + // update the probability on the edge from JumpMBB to Fallthrough. + for (MachineBasicBlock::succ_iterator SI = JumpMBB->succ_begin(), + SE = JumpMBB->succ_end(); + SI != SE; ++SI) { + if (*SI == DefaultMBB) { + JumpProb += DefaultProb / 2; + FallthroughProb -= DefaultProb / 2; + JumpMBB->setSuccProbability(SI, DefaultProb / 2); + JumpMBB->normalizeSuccProbs(); + break; + } + } + + if (FallthroughUnreachable) { + // Skip the range check if the fallthrough block is unreachable. + JTH->OmitRangeCheck = true; + } + + if (!JTH->OmitRangeCheck) + addSuccessorWithProb(CurMBB, Fallthrough, FallthroughProb); + addSuccessorWithProb(CurMBB, JumpMBB, JumpProb); + CurMBB->normalizeSuccProbs(); + + // The jump table header will be inserted in our current block, do the + // range check, and fall through to our fallthrough block. + JTH->HeaderBB = CurMBB; + JT->Default = Fallthrough; // FIXME: Move Default to JumpTableHeader. + + // If we're in the right place, emit the jump table header right now. + if (CurMBB == SwitchMBB) { + visitJumpTableHeader(*JT, *JTH, SwitchMBB); + JTH->Emitted = true; + } + break; + } + case CC_BitTests: { + // FIXME: Optimize away range check based on pivot comparisons. + BitTestBlock *BTB = &SL->BitTestCases[I->BTCasesIndex]; + + // The bit test blocks haven't been inserted yet; insert them here. + for (BitTestCase &BTC : BTB->Cases) + CurMF->insert(BBI, BTC.ThisBB); + + // Fill in fields of the BitTestBlock. + BTB->Parent = CurMBB; + BTB->Default = Fallthrough; + + BTB->DefaultProb = UnhandledProbs; + // If the cases in bit test don't form a contiguous range, we evenly + // distribute the probability on the edge to Fallthrough to two + // successors of CurMBB. + if (!BTB->ContiguousRange) { + BTB->Prob += DefaultProb / 2; + BTB->DefaultProb -= DefaultProb / 2; + } + + if (FallthroughUnreachable) { + // Skip the range check if the fallthrough block is unreachable. + BTB->OmitRangeCheck = true; + } + + // If we're in the right place, emit the bit test header right now. + if (CurMBB == SwitchMBB) { + visitBitTestHeader(*BTB, SwitchMBB); + BTB->Emitted = true; + } + break; + } + case CC_Range: { + const Value *RHS, *LHS, *MHS; + ISD::CondCode CC; + if (I->Low == I->High) { + // Check Cond == I->Low. + CC = ISD::SETEQ; + LHS = Cond; + RHS=I->Low; + MHS = nullptr; + } else { + // Check I->Low <= Cond <= I->High. + CC = ISD::SETLE; + LHS = I->Low; + MHS = Cond; + RHS = I->High; + } + + // If Fallthrough is unreachable, fold away the comparison. + if (FallthroughUnreachable) + CC = ISD::SETTRUE; + + // The false probability is the sum of all unhandled cases. + CaseBlock CB(CC, LHS, RHS, MHS, I->MBB, Fallthrough, CurMBB, + getCurSDLoc(), I->Prob, UnhandledProbs); + + if (CurMBB == SwitchMBB) + visitSwitchCase(CB, SwitchMBB); + else + SL->SwitchCases.push_back(CB); + + break; + } + } + CurMBB = Fallthrough; + } +} + +unsigned SelectionDAGBuilder::caseClusterRank(const CaseCluster &CC, + CaseClusterIt First, + CaseClusterIt Last) { + return std::count_if(First, Last + 1, [&](const CaseCluster &X) { + if (X.Prob != CC.Prob) + return X.Prob > CC.Prob; + + // Ties are broken by comparing the case value. + return X.Low->getValue().slt(CC.Low->getValue()); + }); +} + +void SelectionDAGBuilder::splitWorkItem(SwitchWorkList &WorkList, + const SwitchWorkListItem &W, + Value *Cond, + MachineBasicBlock *SwitchMBB) { + assert(W.FirstCluster->Low->getValue().slt(W.LastCluster->Low->getValue()) && + "Clusters not sorted?"); + + assert(W.LastCluster - W.FirstCluster + 1 >= 2 && "Too small to split!"); + + // Balance the tree based on branch probabilities to create a near-optimal (in + // terms of search time given key frequency) binary search tree. See e.g. Kurt + // Mehlhorn "Nearly Optimal Binary Search Trees" (1975). + CaseClusterIt LastLeft = W.FirstCluster; + CaseClusterIt FirstRight = W.LastCluster; + auto LeftProb = LastLeft->Prob + W.DefaultProb / 2; + auto RightProb = FirstRight->Prob + W.DefaultProb / 2; + + // Move LastLeft and FirstRight towards each other from opposite directions to + // find a partitioning of the clusters which balances the probability on both + // sides. If LeftProb and RightProb are equal, alternate which side is + // taken to ensure 0-probability nodes are distributed evenly. + unsigned I = 0; + while (LastLeft + 1 < FirstRight) { + if (LeftProb < RightProb || (LeftProb == RightProb && (I & 1))) + LeftProb += (++LastLeft)->Prob; + else + RightProb += (--FirstRight)->Prob; + I++; + } + + while (true) { + // Our binary search tree differs from a typical BST in that ours can have up + // to three values in each leaf. The pivot selection above doesn't take that + // into account, which means the tree might require more nodes and be less + // efficient. We compensate for this here. + + unsigned NumLeft = LastLeft - W.FirstCluster + 1; + unsigned NumRight = W.LastCluster - FirstRight + 1; + + if (std::min(NumLeft, NumRight) < 3 && std::max(NumLeft, NumRight) > 3) { + // If one side has less than 3 clusters, and the other has more than 3, + // consider taking a cluster from the other side. + + if (NumLeft < NumRight) { + // Consider moving the first cluster on the right to the left side. + CaseCluster &CC = *FirstRight; + unsigned RightSideRank = caseClusterRank(CC, FirstRight, W.LastCluster); + unsigned LeftSideRank = caseClusterRank(CC, W.FirstCluster, LastLeft); + if (LeftSideRank <= RightSideRank) { + // Moving the cluster to the left does not demote it. + ++LastLeft; + ++FirstRight; + continue; + } + } else { + assert(NumRight < NumLeft); + // Consider moving the last element on the left to the right side. + CaseCluster &CC = *LastLeft; + unsigned LeftSideRank = caseClusterRank(CC, W.FirstCluster, LastLeft); + unsigned RightSideRank = caseClusterRank(CC, FirstRight, W.LastCluster); + if (RightSideRank <= LeftSideRank) { + // Moving the cluster to the right does not demot it. + --LastLeft; + --FirstRight; + continue; + } + } + } + break; + } + + assert(LastLeft + 1 == FirstRight); + assert(LastLeft >= W.FirstCluster); + assert(FirstRight <= W.LastCluster); + + // Use the first element on the right as pivot since we will make less-than + // comparisons against it. + CaseClusterIt PivotCluster = FirstRight; + assert(PivotCluster > W.FirstCluster); + assert(PivotCluster <= W.LastCluster); + + CaseClusterIt FirstLeft = W.FirstCluster; + CaseClusterIt LastRight = W.LastCluster; + + const ConstantInt *Pivot = PivotCluster->Low; + + // New blocks will be inserted immediately after the current one. + MachineFunction::iterator BBI(W.MBB); + ++BBI; + + // We will branch to the LHS if Value < Pivot. If LHS is a single cluster, + // we can branch to its destination directly if it's squeezed exactly in + // between the known lower bound and Pivot - 1. + MachineBasicBlock *LeftMBB; + if (FirstLeft == LastLeft && FirstLeft->Kind == CC_Range && + FirstLeft->Low == W.GE && + (FirstLeft->High->getValue() + 1LL) == Pivot->getValue()) { + LeftMBB = FirstLeft->MBB; + } else { + LeftMBB = FuncInfo.MF->CreateMachineBasicBlock(W.MBB->getBasicBlock()); + FuncInfo.MF->insert(BBI, LeftMBB); + WorkList.push_back( + {LeftMBB, FirstLeft, LastLeft, W.GE, Pivot, W.DefaultProb / 2}); + // Put Cond in a virtual register to make it available from the new blocks. + ExportFromCurrentBlock(Cond); + } + + // Similarly, we will branch to the RHS if Value >= Pivot. If RHS is a + // single cluster, RHS.Low == Pivot, and we can branch to its destination + // directly if RHS.High equals the current upper bound. + MachineBasicBlock *RightMBB; + if (FirstRight == LastRight && FirstRight->Kind == CC_Range && + W.LT && (FirstRight->High->getValue() + 1ULL) == W.LT->getValue()) { + RightMBB = FirstRight->MBB; + } else { + RightMBB = FuncInfo.MF->CreateMachineBasicBlock(W.MBB->getBasicBlock()); + FuncInfo.MF->insert(BBI, RightMBB); + WorkList.push_back( + {RightMBB, FirstRight, LastRight, Pivot, W.LT, W.DefaultProb / 2}); + // Put Cond in a virtual register to make it available from the new blocks. + ExportFromCurrentBlock(Cond); + } + + // Create the CaseBlock record that will be used to lower the branch. + CaseBlock CB(ISD::SETLT, Cond, Pivot, nullptr, LeftMBB, RightMBB, W.MBB, + getCurSDLoc(), LeftProb, RightProb); + + if (W.MBB == SwitchMBB) + visitSwitchCase(CB, SwitchMBB); + else + SL->SwitchCases.push_back(CB); +} + +// Scale CaseProb after peeling a case with the probablity of PeeledCaseProb +// from the swith statement. +static BranchProbability scaleCaseProbality(BranchProbability CaseProb, + BranchProbability PeeledCaseProb) { + if (PeeledCaseProb == BranchProbability::getOne()) + return BranchProbability::getZero(); + BranchProbability SwitchProb = PeeledCaseProb.getCompl(); + + uint32_t Numerator = CaseProb.getNumerator(); + uint32_t Denominator = SwitchProb.scale(CaseProb.getDenominator()); + return BranchProbability(Numerator, std::max(Numerator, Denominator)); +} + +// Try to peel the top probability case if it exceeds the threshold. +// Return current MachineBasicBlock for the switch statement if the peeling +// does not occur. +// If the peeling is performed, return the newly created MachineBasicBlock +// for the peeled switch statement. Also update Clusters to remove the peeled +// case. PeeledCaseProb is the BranchProbability for the peeled case. +MachineBasicBlock *SelectionDAGBuilder::peelDominantCaseCluster( + const SwitchInst &SI, CaseClusterVector &Clusters, + BranchProbability &PeeledCaseProb) { + MachineBasicBlock *SwitchMBB = FuncInfo.MBB; + // Don't perform if there is only one cluster or optimizing for size. + if (SwitchPeelThreshold > 100 || !FuncInfo.BPI || Clusters.size() < 2 || + TM.getOptLevel() == CodeGenOpt::None || + SwitchMBB->getParent()->getFunction().hasMinSize()) + return SwitchMBB; + + BranchProbability TopCaseProb = BranchProbability(SwitchPeelThreshold, 100); + unsigned PeeledCaseIndex = 0; + bool SwitchPeeled = false; + for (unsigned Index = 0; Index < Clusters.size(); ++Index) { + CaseCluster &CC = Clusters[Index]; + if (CC.Prob < TopCaseProb) + continue; + TopCaseProb = CC.Prob; + PeeledCaseIndex = Index; + SwitchPeeled = true; + } + if (!SwitchPeeled) + return SwitchMBB; + + LLVM_DEBUG(dbgs() << "Peeled one top case in switch stmt, prob: " + << TopCaseProb << "\n"); + + // Record the MBB for the peeled switch statement. + MachineFunction::iterator BBI(SwitchMBB); + ++BBI; + MachineBasicBlock *PeeledSwitchMBB = + FuncInfo.MF->CreateMachineBasicBlock(SwitchMBB->getBasicBlock()); + FuncInfo.MF->insert(BBI, PeeledSwitchMBB); + + ExportFromCurrentBlock(SI.getCondition()); + auto PeeledCaseIt = Clusters.begin() + PeeledCaseIndex; + SwitchWorkListItem W = {SwitchMBB, PeeledCaseIt, PeeledCaseIt, + nullptr, nullptr, TopCaseProb.getCompl()}; + lowerWorkItem(W, SI.getCondition(), SwitchMBB, PeeledSwitchMBB); + + Clusters.erase(PeeledCaseIt); + for (CaseCluster &CC : Clusters) { + LLVM_DEBUG( + dbgs() << "Scale the probablity for one cluster, before scaling: " + << CC.Prob << "\n"); + CC.Prob = scaleCaseProbality(CC.Prob, TopCaseProb); + LLVM_DEBUG(dbgs() << "After scaling: " << CC.Prob << "\n"); + } + PeeledCaseProb = TopCaseProb; + return PeeledSwitchMBB; +} + +void SelectionDAGBuilder::visitSwitch(const SwitchInst &SI) { + // Extract cases from the switch. + BranchProbabilityInfo *BPI = FuncInfo.BPI; + CaseClusterVector Clusters; + Clusters.reserve(SI.getNumCases()); + for (auto I : SI.cases()) { + MachineBasicBlock *Succ = FuncInfo.MBBMap[I.getCaseSuccessor()]; + const ConstantInt *CaseVal = I.getCaseValue(); + BranchProbability Prob = + BPI ? BPI->getEdgeProbability(SI.getParent(), I.getSuccessorIndex()) + : BranchProbability(1, SI.getNumCases() + 1); + Clusters.push_back(CaseCluster::range(CaseVal, CaseVal, Succ, Prob)); + } + + MachineBasicBlock *DefaultMBB = FuncInfo.MBBMap[SI.getDefaultDest()]; + + // Cluster adjacent cases with the same destination. We do this at all + // optimization levels because it's cheap to do and will make codegen faster + // if there are many clusters. + sortAndRangeify(Clusters); + + // The branch probablity of the peeled case. + BranchProbability PeeledCaseProb = BranchProbability::getZero(); + MachineBasicBlock *PeeledSwitchMBB = + peelDominantCaseCluster(SI, Clusters, PeeledCaseProb); + + // If there is only the default destination, jump there directly. + MachineBasicBlock *SwitchMBB = FuncInfo.MBB; + if (Clusters.empty()) { + assert(PeeledSwitchMBB == SwitchMBB); + SwitchMBB->addSuccessor(DefaultMBB); + if (DefaultMBB != NextBlock(SwitchMBB)) { + DAG.setRoot(DAG.getNode(ISD::BR, getCurSDLoc(), MVT::Other, + getControlRoot(), DAG.getBasicBlock(DefaultMBB))); + } + return; + } + + SL->findJumpTables(Clusters, &SI, DefaultMBB, DAG.getPSI(), DAG.getBFI()); + SL->findBitTestClusters(Clusters, &SI); + + LLVM_DEBUG({ + dbgs() << "Case clusters: "; + for (const CaseCluster &C : Clusters) { + if (C.Kind == CC_JumpTable) + dbgs() << "JT:"; + if (C.Kind == CC_BitTests) + dbgs() << "BT:"; + + C.Low->getValue().print(dbgs(), true); + if (C.Low != C.High) { + dbgs() << '-'; + C.High->getValue().print(dbgs(), true); + } + dbgs() << ' '; + } + dbgs() << '\n'; + }); + + assert(!Clusters.empty()); + SwitchWorkList WorkList; + CaseClusterIt First = Clusters.begin(); + CaseClusterIt Last = Clusters.end() - 1; + auto DefaultProb = getEdgeProbability(PeeledSwitchMBB, DefaultMBB); + // Scale the branchprobability for DefaultMBB if the peel occurs and + // DefaultMBB is not replaced. + if (PeeledCaseProb != BranchProbability::getZero() && + DefaultMBB == FuncInfo.MBBMap[SI.getDefaultDest()]) + DefaultProb = scaleCaseProbality(DefaultProb, PeeledCaseProb); + WorkList.push_back( + {PeeledSwitchMBB, First, Last, nullptr, nullptr, DefaultProb}); + + while (!WorkList.empty()) { + SwitchWorkListItem W = WorkList.back(); + WorkList.pop_back(); + unsigned NumClusters = W.LastCluster - W.FirstCluster + 1; + + if (NumClusters > 3 && TM.getOptLevel() != CodeGenOpt::None && + !DefaultMBB->getParent()->getFunction().hasMinSize()) { + // For optimized builds, lower large range as a balanced binary tree. + splitWorkItem(WorkList, W, SI.getCondition(), SwitchMBB); + continue; + } + + lowerWorkItem(W, SI.getCondition(), SwitchMBB, DefaultMBB); + } +} + +void SelectionDAGBuilder::visitFreeze(const FreezeInst &I) { + SDValue N = getValue(I.getOperand(0)); + setValue(&I, N); +} |