1 files changed, 179 insertions, 120 deletions

diff --git a/lib/CodeGen/SelectionDAG/FastISel.cpp b/lib/CodeGen/SelectionDAG/FastISel.cpp
index 490b857b0e9c8..3af948288daff 100644
--- a/lib/CodeGen/SelectionDAG/FastISel.cpp
+++ b/lib/CodeGen/SelectionDAG/FastISel.cpp
@@ -43,6 +43,7 @@
 #include "llvm/GlobalVariable.h"
 #include "llvm/Instructions.h"
 #include "llvm/IntrinsicInst.h"
+#include "llvm/Operator.h"
 #include "llvm/CodeGen/FastISel.h"
 #include "llvm/CodeGen/FunctionLoweringInfo.h"
 #include "llvm/CodeGen/MachineInstrBuilder.h"
@@ -121,10 +122,9 @@ unsigned FastISel::getRegForValue(const Value *V) {
   // only locally. This is because Instructions already have the SSA
   // def-dominates-use requirement enforced.
   DenseMap<const Value *, unsigned>::iterator I = FuncInfo.ValueMap.find(V);
-  if (I != FuncInfo.ValueMap.end()) {
-    unsigned Reg = I->second;
-    return Reg;
-  }
+  if (I != FuncInfo.ValueMap.end())
+    return I->second;
+
   unsigned Reg = LocalValueMap[V];
   if (Reg != 0)
     return Reg;
@@ -164,8 +164,12 @@ unsigned FastISel::materializeRegForValue(const Value *V, MVT VT) {
     Reg =
       getRegForValue(Constant::getNullValue(TD.getIntPtrType(V->getContext())));
   } else if (const ConstantFP *CF = dyn_cast<ConstantFP>(V)) {
-    // Try to emit the constant directly.
-    Reg = FastEmit_f(VT, VT, ISD::ConstantFP, CF);
+    if (CF->isNullValue()) {
+      Reg = TargetMaterializeFloatZero(CF);
+    } else {
+      // Try to emit the constant directly.
+      Reg = FastEmit_f(VT, VT, ISD::ConstantFP, CF);
+    }
 
     if (!Reg) {
       // Try to emit the constant by using an integer constant with a cast.
@@ -330,23 +334,51 @@ bool FastISel::SelectBinaryOp(const User *I, unsigned ISDOpcode) {
       return false;
   }
 
+  // Check if the first operand is a constant, and handle it as "ri".  At -O0,
+  // we don't have anything that canonicalizes operand order.
+  if (ConstantInt *CI = dyn_cast<ConstantInt>(I->getOperand(0)))
+    if (isa<Instruction>(I) && cast<Instruction>(I)->isCommutative()) {
+      unsigned Op1 = getRegForValue(I->getOperand(1));
+      if (Op1 == 0) return false;
+
+      bool Op1IsKill = hasTrivialKill(I->getOperand(1));
+
+      unsigned ResultReg = FastEmit_ri_(VT.getSimpleVT(), ISDOpcode, Op1,
+                                        Op1IsKill, CI->getZExtValue(),
+                                        VT.getSimpleVT());
+      if (ResultReg == 0) return false;
+
+      // We successfully emitted code for the given LLVM Instruction.
+      UpdateValueMap(I, ResultReg);
+      return true;
+    }
+
+
   unsigned Op0 = getRegForValue(I->getOperand(0));
-  if (Op0 == 0)
-    // Unhandled operand. Halt "fast" selection and bail.
+  if (Op0 == 0)   // Unhandled operand. Halt "fast" selection and bail.
     return false;
 
   bool Op0IsKill = hasTrivialKill(I->getOperand(0));
 
   // Check if the second operand is a constant and handle it appropriately.
   if (ConstantInt *CI = dyn_cast<ConstantInt>(I->getOperand(1))) {
-    unsigned ResultReg = FastEmit_ri(VT.getSimpleVT(), VT.getSimpleVT(),
-                                     ISDOpcode, Op0, Op0IsKill,
-                                     CI->getZExtValue());
-    if (ResultReg != 0) {
-      // We successfully emitted code for the given LLVM Instruction.
-      UpdateValueMap(I, ResultReg);
-      return true;
+    uint64_t Imm = CI->getZExtValue();
+
+    // Transform "sdiv exact X, 8" -> "sra X, 3".
+    if (ISDOpcode == ISD::SDIV && isa<BinaryOperator>(I) &&
+        cast<BinaryOperator>(I)->isExact() &&
+        isPowerOf2_64(Imm)) {
+      Imm = Log2_64(Imm);
+      ISDOpcode = ISD::SRA;
     }
+
+    unsigned ResultReg = FastEmit_ri_(VT.getSimpleVT(), ISDOpcode, Op0,
+                                      Op0IsKill, Imm, VT.getSimpleVT());
+    if (ResultReg == 0) return false;
+
+    // We successfully emitted code for the given LLVM Instruction.
+    UpdateValueMap(I, ResultReg);
+    return true;
   }
 
   // Check if the second operand is a constant float.
@@ -454,15 +486,35 @@ bool FastISel::SelectGetElementPtr(const User *I) {
 }
 
 bool FastISel::SelectCall(const User *I) {
-  const Function *F = cast<CallInst>(I)->getCalledFunction();
+  const CallInst *Call = cast<CallInst>(I);
+
+  // Handle simple inline asms.
+  if (const InlineAsm *IA = dyn_cast<InlineAsm>(Call->getArgOperand(0))) {
+    // Don't attempt to handle constraints.
+    if (!IA->getConstraintString().empty())
+      return false;
+
+    unsigned ExtraInfo = 0;
+    if (IA->hasSideEffects())
+      ExtraInfo |= InlineAsm::Extra_HasSideEffects;
+    if (IA->isAlignStack())
+      ExtraInfo |= InlineAsm::Extra_IsAlignStack;
+
+    BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
+            TII.get(TargetOpcode::INLINEASM))
+      .addExternalSymbol(IA->getAsmString().c_str())
+      .addImm(ExtraInfo);
+    return true;
+  }
+
+  const Function *F = Call->getCalledFunction();
   if (!F) return false;
 
   // Handle selected intrinsic function calls.
-  unsigned IID = F->getIntrinsicID();
-  switch (IID) {
+  switch (F->getIntrinsicID()) {
   default: break;
   case Intrinsic::dbg_declare: {
-    const DbgDeclareInst *DI = cast<DbgDeclareInst>(I);
+    const DbgDeclareInst *DI = cast<DbgDeclareInst>(Call);
     if (!DIVariable(DI->getVariable()).Verify() ||
         !FuncInfo.MF->getMMI().hasDebugInfo())
       return true;
@@ -494,7 +546,7 @@ bool FastISel::SelectCall(const User *I) {
   }
   case Intrinsic::dbg_value: {
     // This form of DBG_VALUE is target-independent.
-    const DbgValueInst *DI = cast<DbgValueInst>(I);
+    const DbgValueInst *DI = cast<DbgValueInst>(Call);
     const TargetInstrDesc &II = TII.get(TargetOpcode::DBG_VALUE);
     const Value *V = DI->getValue();
     if (!V) {
@@ -523,65 +575,58 @@ bool FastISel::SelectCall(const User *I) {
     return true;
   }
   case Intrinsic::eh_exception: {
-    EVT VT = TLI.getValueType(I->getType());
-    switch (TLI.getOperationAction(ISD::EXCEPTIONADDR, VT)) {
-    default: break;
-    case TargetLowering::Expand: {
-      assert(FuncInfo.MBB->isLandingPad() &&
-             "Call to eh.exception not in landing pad!");
-      unsigned Reg = TLI.getExceptionAddressRegister();
-      const TargetRegisterClass *RC = TLI.getRegClassFor(VT);
-      unsigned ResultReg = createResultReg(RC);
-      BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TargetOpcode::COPY),
-              ResultReg).addReg(Reg);
-      UpdateValueMap(I, ResultReg);
-      return true;
-    }
-    }
-    break;
+    EVT VT = TLI.getValueType(Call->getType());
+    if (TLI.getOperationAction(ISD::EXCEPTIONADDR, VT)!=TargetLowering::Expand)
+      break;
+
+    assert(FuncInfo.MBB->isLandingPad() &&
+           "Call to eh.exception not in landing pad!");
+    unsigned Reg = TLI.getExceptionAddressRegister();
+    const TargetRegisterClass *RC = TLI.getRegClassFor(VT);
+    unsigned ResultReg = createResultReg(RC);
+    BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TargetOpcode::COPY),
+            ResultReg).addReg(Reg);
+    UpdateValueMap(Call, ResultReg);
+    return true;
   }
   case Intrinsic::eh_selector: {
-    EVT VT = TLI.getValueType(I->getType());
-    switch (TLI.getOperationAction(ISD::EHSELECTION, VT)) {
-    default: break;
-    case TargetLowering::Expand: {
-      if (FuncInfo.MBB->isLandingPad())
-        AddCatchInfo(*cast<CallInst>(I), &FuncInfo.MF->getMMI(), FuncInfo.MBB);
-      else {
+    EVT VT = TLI.getValueType(Call->getType());
+    if (TLI.getOperationAction(ISD::EHSELECTION, VT) != TargetLowering::Expand)
+      break;
+    if (FuncInfo.MBB->isLandingPad())
+      AddCatchInfo(*Call, &FuncInfo.MF->getMMI(), FuncInfo.MBB);
+    else {
 #ifndef NDEBUG
-        FuncInfo.CatchInfoLost.insert(cast<CallInst>(I));
+      FuncInfo.CatchInfoLost.insert(Call);
 #endif
-        // FIXME: Mark exception selector register as live in.  Hack for PR1508.
-        unsigned Reg = TLI.getExceptionSelectorRegister();
-        if (Reg) FuncInfo.MBB->addLiveIn(Reg);
-      }
-
+      // FIXME: Mark exception selector register as live in.  Hack for PR1508.
       unsigned Reg = TLI.getExceptionSelectorRegister();
-      EVT SrcVT = TLI.getPointerTy();
-      const TargetRegisterClass *RC = TLI.getRegClassFor(SrcVT);
-      unsigned ResultReg = createResultReg(RC);
-      BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TargetOpcode::COPY),
-              ResultReg).addReg(Reg);
-
-      bool ResultRegIsKill = hasTrivialKill(I);
-
-      // Cast the register to the type of the selector.
-      if (SrcVT.bitsGT(MVT::i32))
-        ResultReg = FastEmit_r(SrcVT.getSimpleVT(), MVT::i32, ISD::TRUNCATE,
-                               ResultReg, ResultRegIsKill);
-      else if (SrcVT.bitsLT(MVT::i32))
-        ResultReg = FastEmit_r(SrcVT.getSimpleVT(), MVT::i32,
-                               ISD::SIGN_EXTEND, ResultReg, ResultRegIsKill);
-      if (ResultReg == 0)
-        // Unhandled operand. Halt "fast" selection and bail.
-        return false;
+      if (Reg) FuncInfo.MBB->addLiveIn(Reg);
+    }
 
-      UpdateValueMap(I, ResultReg);
+    unsigned Reg = TLI.getExceptionSelectorRegister();
+    EVT SrcVT = TLI.getPointerTy();
+    const TargetRegisterClass *RC = TLI.getRegClassFor(SrcVT);
+    unsigned ResultReg = createResultReg(RC);
+    BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TargetOpcode::COPY),
+            ResultReg).addReg(Reg);
+
+    bool ResultRegIsKill = hasTrivialKill(Call);
+
+    // Cast the register to the type of the selector.
+    if (SrcVT.bitsGT(MVT::i32))
+      ResultReg = FastEmit_r(SrcVT.getSimpleVT(), MVT::i32, ISD::TRUNCATE,
+                             ResultReg, ResultRegIsKill);
+    else if (SrcVT.bitsLT(MVT::i32))
+      ResultReg = FastEmit_r(SrcVT.getSimpleVT(), MVT::i32,
+                             ISD::SIGN_EXTEND, ResultReg, ResultRegIsKill);
+    if (ResultReg == 0)
+      // Unhandled operand. Halt "fast" selection and bail.
+      return false;
 
-      return true;
-    }
-    }
-    break;
+    UpdateValueMap(Call, ResultReg);
+
+    return true;
   }
   }
 
@@ -966,59 +1011,33 @@ unsigned FastISel::FastEmit_rri(MVT, MVT,
 unsigned FastISel::FastEmit_ri_(MVT VT, unsigned Opcode,
                                 unsigned Op0, bool Op0IsKill,
                                 uint64_t Imm, MVT ImmType) {
+  // If this is a multiply by a power of two, emit this as a shift left.
+  if (Opcode == ISD::MUL && isPowerOf2_64(Imm)) {
+    Opcode = ISD::SHL;
+    Imm = Log2_64(Imm);
+  } else if (Opcode == ISD::UDIV && isPowerOf2_64(Imm)) {
+    // div x, 8 -> srl x, 3
+    Opcode = ISD::SRL;
+    Imm = Log2_64(Imm);
+  }
+
+  // Horrible hack (to be removed), check to make sure shift amounts are
+  // in-range.
+  if ((Opcode == ISD::SHL || Opcode == ISD::SRA || Opcode == ISD::SRL) &&
+      Imm >= VT.getSizeInBits())
+    return 0;
+
   // First check if immediate type is legal. If not, we can't use the ri form.
   unsigned ResultReg = FastEmit_ri(VT, VT, Opcode, Op0, Op0IsKill, Imm);
   if (ResultReg != 0)
     return ResultReg;
   unsigned MaterialReg = FastEmit_i(ImmType, ImmType, ISD::Constant, Imm);
-  if (MaterialReg == 0)
-    return 0;
-  return FastEmit_rr(VT, VT, Opcode,
-                     Op0, Op0IsKill,
-                     MaterialReg, /*Kill=*/true);
-}
-
-/// FastEmit_rf_ - This method is a wrapper of FastEmit_ri. It first tries
-/// to emit an instruction with a floating-point immediate operand using
-/// FastEmit_rf. If that fails, it materializes the immediate into a register
-/// and try FastEmit_rr instead.
-unsigned FastISel::FastEmit_rf_(MVT VT, unsigned Opcode,
-                                unsigned Op0, bool Op0IsKill,
-                                const ConstantFP *FPImm, MVT ImmType) {
-  // First check if immediate type is legal. If not, we can't use the rf form.
-  unsigned ResultReg = FastEmit_rf(VT, VT, Opcode, Op0, Op0IsKill, FPImm);
-  if (ResultReg != 0)
-    return ResultReg;
-
-  // Materialize the constant in a register.
-  unsigned MaterialReg = FastEmit_f(ImmType, ImmType, ISD::ConstantFP, FPImm);
   if (MaterialReg == 0) {
-    // If the target doesn't have a way to directly enter a floating-point
-    // value into a register, use an alternate approach.
-    // TODO: The current approach only supports floating-point constants
-    // that can be constructed by conversion from integer values. This should
-    // be replaced by code that creates a load from a constant-pool entry,
-    // which will require some target-specific work.
-    const APFloat &Flt = FPImm->getValueAPF();
-    EVT IntVT = TLI.getPointerTy();
-
-    uint64_t x[2];
-    uint32_t IntBitWidth = IntVT.getSizeInBits();
-    bool isExact;
-    (void) Flt.convertToInteger(x, IntBitWidth, /*isSigned=*/true,
-                             APFloat::rmTowardZero, &isExact);
-    if (!isExact)
-      return 0;
-    APInt IntVal(IntBitWidth, 2, x);
-
-    unsigned IntegerReg = FastEmit_i(IntVT.getSimpleVT(), IntVT.getSimpleVT(),
-                                     ISD::Constant, IntVal.getZExtValue());
-    if (IntegerReg == 0)
-      return 0;
-    MaterialReg = FastEmit_r(IntVT.getSimpleVT(), VT,
-                             ISD::SINT_TO_FP, IntegerReg, /*Kill=*/true);
-    if (MaterialReg == 0)
-      return 0;
+    // This is a bit ugly/slow, but failing here means falling out of
+    // fast-isel, which would be very slow.
+    const IntegerType *ITy = IntegerType::get(FuncInfo.Fn->getContext(),
+                                              VT.getSizeInBits());
+    MaterialReg = getRegForValue(ConstantInt::get(ITy, Imm));
   }
   return FastEmit_rr(VT, VT, Opcode,
                      Op0, Op0IsKill,
@@ -1099,6 +1118,29 @@ unsigned FastISel::FastEmitInst_ri(unsigned MachineInstOpcode,
   return ResultReg;
 }
 
+unsigned FastISel::FastEmitInst_rii(unsigned MachineInstOpcode,
+                                   const TargetRegisterClass *RC,
+                                   unsigned Op0, bool Op0IsKill,
+                                   uint64_t Imm1, uint64_t Imm2) {
+  unsigned ResultReg = createResultReg(RC);
+  const TargetInstrDesc &II = TII.get(MachineInstOpcode);
+
+  if (II.getNumDefs() >= 1)
+    BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
+      .addReg(Op0, Op0IsKill * RegState::Kill)
+      .addImm(Imm1)
+      .addImm(Imm2);
+  else {
+    BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
+      .addReg(Op0, Op0IsKill * RegState::Kill)
+      .addImm(Imm1)
+      .addImm(Imm2);
+    BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TargetOpcode::COPY),
+            ResultReg).addReg(II.ImplicitDefs[0]);
+  }
+  return ResultReg;
+}
+
 unsigned FastISel::FastEmitInst_rf(unsigned MachineInstOpcode,
                                    const TargetRegisterClass *RC,
                                    unsigned Op0, bool Op0IsKill,
@@ -1160,6 +1202,23 @@ unsigned FastISel::FastEmitInst_i(unsigned MachineInstOpcode,
   return ResultReg;
 }
 
+unsigned FastISel::FastEmitInst_ii(unsigned MachineInstOpcode,
+                                  const TargetRegisterClass *RC,
+                                  uint64_t Imm1, uint64_t Imm2) {
+  unsigned ResultReg = createResultReg(RC);
+  const TargetInstrDesc &II = TII.get(MachineInstOpcode);
+
+  if (II.getNumDefs() >= 1)
+    BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
+      .addImm(Imm1).addImm(Imm2);
+  else {
+    BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II).addImm(Imm1).addImm(Imm2);
+    BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(TargetOpcode::COPY),
+            ResultReg).addReg(II.ImplicitDefs[0]);
+  }
+  return ResultReg;
+}
+
 unsigned FastISel::FastEmitInst_extractsubreg(MVT RetVT,
                                               unsigned Op0, bool Op0IsKill,
                                               uint32_t Idx) {
@@ -1215,7 +1274,7 @@ bool FastISel::HandlePHINodesInSuccessorBlocks(const BasicBlock *LLVMBB) {
       // Only handle legal types. Two interesting things to note here. First,
       // by bailing out early, we may leave behind some dead instructions,
       // since SelectionDAG's HandlePHINodesInSuccessorBlocks will insert its
-      // own moves. Second, this check is necessary becuase FastISel doesn't
+      // own moves. Second, this check is necessary because FastISel doesn't
       // use CreateRegs to create registers, so it always creates
       // exactly one register for each non-void instruction.
       EVT VT = TLI.getValueType(PN->getType(), /*AllowUnknown=*/true);