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diff --git a/contrib/llvm/lib/Target/X86/X86CodeEmitter.cpp b/contrib/llvm/lib/Target/X86/X86CodeEmitter.cpp
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+++ b/contrib/llvm/lib/Target/X86/X86CodeEmitter.cpp
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+//===-- X86/X86CodeEmitter.cpp - Convert X86 code to machine code ---------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains the pass that transforms the X86 machine instructions into
+// relocatable machine code.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "x86-emitter"
+#include "X86InstrInfo.h"
+#include "X86JITInfo.h"
+#include "X86Subtarget.h"
+#include "X86TargetMachine.h"
+#include "X86Relocations.h"
+#include "X86.h"
+#include "llvm/LLVMContext.h"
+#include "llvm/PassManager.h"
+#include "llvm/CodeGen/JITCodeEmitter.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/CodeGen/MachineInstr.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
+#include "llvm/CodeGen/Passes.h"
+#include "llvm/Function.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/MC/MCCodeEmitter.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCInst.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Target/TargetOptions.h"
+using namespace llvm;
+
+STATISTIC(NumEmitted, "Number of machine instructions emitted");
+
+namespace {
+ template<class CodeEmitter>
+ class Emitter : public MachineFunctionPass {
+ const X86InstrInfo *II;
+ const TargetData *TD;
+ X86TargetMachine &TM;
+ CodeEmitter &MCE;
+ MachineModuleInfo *MMI;
+ intptr_t PICBaseOffset;
+ bool Is64BitMode;
+ bool IsPIC;
+ public:
+ static char ID;
+ explicit Emitter(X86TargetMachine &tm, CodeEmitter &mce)
+ : MachineFunctionPass(&ID), II(0), TD(0), TM(tm),
+ MCE(mce), PICBaseOffset(0), Is64BitMode(false),
+ IsPIC(TM.getRelocationModel() == Reloc::PIC_) {}
+ Emitter(X86TargetMachine &tm, CodeEmitter &mce,
+ const X86InstrInfo &ii, const TargetData &td, bool is64)
+ : MachineFunctionPass(&ID), II(&ii), TD(&td), TM(tm),
+ MCE(mce), PICBaseOffset(0), Is64BitMode(is64),
+ IsPIC(TM.getRelocationModel() == Reloc::PIC_) {}
+
+ bool runOnMachineFunction(MachineFunction &MF);
+
+ virtual const char *getPassName() const {
+ return "X86 Machine Code Emitter";
+ }
+
+ void emitInstruction(const MachineInstr &MI,
+ const TargetInstrDesc *Desc);
+
+ void getAnalysisUsage(AnalysisUsage &AU) const {
+ AU.setPreservesAll();
+ AU.addRequired<MachineModuleInfo>();
+ MachineFunctionPass::getAnalysisUsage(AU);
+ }
+
+ private:
+ void emitPCRelativeBlockAddress(MachineBasicBlock *MBB);
+ void emitGlobalAddress(const GlobalValue *GV, unsigned Reloc,
+ intptr_t Disp = 0, intptr_t PCAdj = 0,
+ bool Indirect = false);
+ void emitExternalSymbolAddress(const char *ES, unsigned Reloc);
+ void emitConstPoolAddress(unsigned CPI, unsigned Reloc, intptr_t Disp = 0,
+ intptr_t PCAdj = 0);
+ void emitJumpTableAddress(unsigned JTI, unsigned Reloc,
+ intptr_t PCAdj = 0);
+
+ void emitDisplacementField(const MachineOperand *RelocOp, int DispVal,
+ intptr_t Adj = 0, bool IsPCRel = true);
+
+ void emitRegModRMByte(unsigned ModRMReg, unsigned RegOpcodeField);
+ void emitRegModRMByte(unsigned RegOpcodeField);
+ void emitSIBByte(unsigned SS, unsigned Index, unsigned Base);
+ void emitConstant(uint64_t Val, unsigned Size);
+
+ void emitMemModRMByte(const MachineInstr &MI,
+ unsigned Op, unsigned RegOpcodeField,
+ intptr_t PCAdj = 0);
+
+ unsigned getX86RegNum(unsigned RegNo) const;
+ };
+
+template<class CodeEmitter>
+ char Emitter<CodeEmitter>::ID = 0;
+} // end anonymous namespace.
+
+/// createX86CodeEmitterPass - Return a pass that emits the collected X86 code
+/// to the specified templated MachineCodeEmitter object.
+FunctionPass *llvm::createX86JITCodeEmitterPass(X86TargetMachine &TM,
+ JITCodeEmitter &JCE) {
+ return new Emitter<JITCodeEmitter>(TM, JCE);
+}
+
+template<class CodeEmitter>
+bool Emitter<CodeEmitter>::runOnMachineFunction(MachineFunction &MF) {
+ MMI = &getAnalysis<MachineModuleInfo>();
+ MCE.setModuleInfo(MMI);
+
+ II = TM.getInstrInfo();
+ TD = TM.getTargetData();
+ Is64BitMode = TM.getSubtarget<X86Subtarget>().is64Bit();
+ IsPIC = TM.getRelocationModel() == Reloc::PIC_;
+
+ do {
+ DEBUG(dbgs() << "JITTing function '"
+ << MF.getFunction()->getName() << "'\n");
+ MCE.startFunction(MF);
+ for (MachineFunction::iterator MBB = MF.begin(), E = MF.end();
+ MBB != E; ++MBB) {
+ MCE.StartMachineBasicBlock(MBB);
+ for (MachineBasicBlock::const_iterator I = MBB->begin(), E = MBB->end();
+ I != E; ++I) {
+ const TargetInstrDesc &Desc = I->getDesc();
+ emitInstruction(*I, &Desc);
+ // MOVPC32r is basically a call plus a pop instruction.
+ if (Desc.getOpcode() == X86::MOVPC32r)
+ emitInstruction(*I, &II->get(X86::POP32r));
+ NumEmitted++; // Keep track of the # of mi's emitted
+ }
+ }
+ } while (MCE.finishFunction(MF));
+
+ return false;
+}
+
+/// emitPCRelativeBlockAddress - This method keeps track of the information
+/// necessary to resolve the address of this block later and emits a dummy
+/// value.
+///
+template<class CodeEmitter>
+void Emitter<CodeEmitter>::emitPCRelativeBlockAddress(MachineBasicBlock *MBB) {
+ // Remember where this reference was and where it is to so we can
+ // deal with it later.
+ MCE.addRelocation(MachineRelocation::getBB(MCE.getCurrentPCOffset(),
+ X86::reloc_pcrel_word, MBB));
+ MCE.emitWordLE(0);
+}
+
+/// emitGlobalAddress - Emit the specified address to the code stream assuming
+/// this is part of a "take the address of a global" instruction.
+///
+template<class CodeEmitter>
+void Emitter<CodeEmitter>::emitGlobalAddress(const GlobalValue *GV,
+ unsigned Reloc,
+ intptr_t Disp /* = 0 */,
+ intptr_t PCAdj /* = 0 */,
+ bool Indirect /* = false */) {
+ intptr_t RelocCST = Disp;
+ if (Reloc == X86::reloc_picrel_word)
+ RelocCST = PICBaseOffset;
+ else if (Reloc == X86::reloc_pcrel_word)
+ RelocCST = PCAdj;
+ MachineRelocation MR = Indirect
+ ? MachineRelocation::getIndirectSymbol(MCE.getCurrentPCOffset(), Reloc,
+ const_cast<GlobalValue *>(GV),
+ RelocCST, false)
+ : MachineRelocation::getGV(MCE.getCurrentPCOffset(), Reloc,
+ const_cast<GlobalValue *>(GV), RelocCST, false);
+ MCE.addRelocation(MR);
+ // The relocated value will be added to the displacement
+ if (Reloc == X86::reloc_absolute_dword)
+ MCE.emitDWordLE(Disp);
+ else
+ MCE.emitWordLE((int32_t)Disp);
+}
+
+/// emitExternalSymbolAddress - Arrange for the address of an external symbol to
+/// be emitted to the current location in the function, and allow it to be PC
+/// relative.
+template<class CodeEmitter>
+void Emitter<CodeEmitter>::emitExternalSymbolAddress(const char *ES,
+ unsigned Reloc) {
+ intptr_t RelocCST = (Reloc == X86::reloc_picrel_word) ? PICBaseOffset : 0;
+
+ // X86 never needs stubs because instruction selection will always pick
+ // an instruction sequence that is large enough to hold any address
+ // to a symbol.
+ // (see X86ISelLowering.cpp, near 2039: X86TargetLowering::LowerCall)
+ bool NeedStub = false;
+ MCE.addRelocation(MachineRelocation::getExtSym(MCE.getCurrentPCOffset(),
+ Reloc, ES, RelocCST,
+ 0, NeedStub));
+ if (Reloc == X86::reloc_absolute_dword)
+ MCE.emitDWordLE(0);
+ else
+ MCE.emitWordLE(0);
+}
+
+/// emitConstPoolAddress - Arrange for the address of an constant pool
+/// to be emitted to the current location in the function, and allow it to be PC
+/// relative.
+template<class CodeEmitter>
+void Emitter<CodeEmitter>::emitConstPoolAddress(unsigned CPI, unsigned Reloc,
+ intptr_t Disp /* = 0 */,
+ intptr_t PCAdj /* = 0 */) {
+ intptr_t RelocCST = 0;
+ if (Reloc == X86::reloc_picrel_word)
+ RelocCST = PICBaseOffset;
+ else if (Reloc == X86::reloc_pcrel_word)
+ RelocCST = PCAdj;
+ MCE.addRelocation(MachineRelocation::getConstPool(MCE.getCurrentPCOffset(),
+ Reloc, CPI, RelocCST));
+ // The relocated value will be added to the displacement
+ if (Reloc == X86::reloc_absolute_dword)
+ MCE.emitDWordLE(Disp);
+ else
+ MCE.emitWordLE((int32_t)Disp);
+}
+
+/// emitJumpTableAddress - Arrange for the address of a jump table to
+/// be emitted to the current location in the function, and allow it to be PC
+/// relative.
+template<class CodeEmitter>
+void Emitter<CodeEmitter>::emitJumpTableAddress(unsigned JTI, unsigned Reloc,
+ intptr_t PCAdj /* = 0 */) {
+ intptr_t RelocCST = 0;
+ if (Reloc == X86::reloc_picrel_word)
+ RelocCST = PICBaseOffset;
+ else if (Reloc == X86::reloc_pcrel_word)
+ RelocCST = PCAdj;
+ MCE.addRelocation(MachineRelocation::getJumpTable(MCE.getCurrentPCOffset(),
+ Reloc, JTI, RelocCST));
+ // The relocated value will be added to the displacement
+ if (Reloc == X86::reloc_absolute_dword)
+ MCE.emitDWordLE(0);
+ else
+ MCE.emitWordLE(0);
+}
+
+template<class CodeEmitter>
+unsigned Emitter<CodeEmitter>::getX86RegNum(unsigned RegNo) const {
+ return X86RegisterInfo::getX86RegNum(RegNo);
+}
+
+inline static unsigned char ModRMByte(unsigned Mod, unsigned RegOpcode,
+ unsigned RM) {
+ assert(Mod < 4 && RegOpcode < 8 && RM < 8 && "ModRM Fields out of range!");
+ return RM | (RegOpcode << 3) | (Mod << 6);
+}
+
+template<class CodeEmitter>
+void Emitter<CodeEmitter>::emitRegModRMByte(unsigned ModRMReg,
+ unsigned RegOpcodeFld){
+ MCE.emitByte(ModRMByte(3, RegOpcodeFld, getX86RegNum(ModRMReg)));
+}
+
+template<class CodeEmitter>
+void Emitter<CodeEmitter>::emitRegModRMByte(unsigned RegOpcodeFld) {
+ MCE.emitByte(ModRMByte(3, RegOpcodeFld, 0));
+}
+
+template<class CodeEmitter>
+void Emitter<CodeEmitter>::emitSIBByte(unsigned SS,
+ unsigned Index,
+ unsigned Base) {
+ // SIB byte is in the same format as the ModRMByte...
+ MCE.emitByte(ModRMByte(SS, Index, Base));
+}
+
+template<class CodeEmitter>
+void Emitter<CodeEmitter>::emitConstant(uint64_t Val, unsigned Size) {
+ // Output the constant in little endian byte order...
+ for (unsigned i = 0; i != Size; ++i) {
+ MCE.emitByte(Val & 255);
+ Val >>= 8;
+ }
+}
+
+/// isDisp8 - Return true if this signed displacement fits in a 8-bit
+/// sign-extended field.
+static bool isDisp8(int Value) {
+ return Value == (signed char)Value;
+}
+
+static bool gvNeedsNonLazyPtr(const MachineOperand &GVOp,
+ const TargetMachine &TM) {
+ // For Darwin-64, simulate the linktime GOT by using the same non-lazy-pointer
+ // mechanism as 32-bit mode.
+ if (TM.getSubtarget<X86Subtarget>().is64Bit() &&
+ !TM.getSubtarget<X86Subtarget>().isTargetDarwin())
+ return false;
+
+ // Return true if this is a reference to a stub containing the address of the
+ // global, not the global itself.
+ return isGlobalStubReference(GVOp.getTargetFlags());
+}
+
+template<class CodeEmitter>
+void Emitter<CodeEmitter>::emitDisplacementField(const MachineOperand *RelocOp,
+ int DispVal,
+ intptr_t Adj /* = 0 */,
+ bool IsPCRel /* = true */) {
+ // If this is a simple integer displacement that doesn't require a relocation,
+ // emit it now.
+ if (!RelocOp) {
+ emitConstant(DispVal, 4);
+ return;
+ }
+
+ // Otherwise, this is something that requires a relocation. Emit it as such
+ // now.
+ unsigned RelocType = Is64BitMode ?
+ (IsPCRel ? X86::reloc_pcrel_word : X86::reloc_absolute_word_sext)
+ : (IsPIC ? X86::reloc_picrel_word : X86::reloc_absolute_word);
+ if (RelocOp->isGlobal()) {
+ // In 64-bit static small code model, we could potentially emit absolute.
+ // But it's probably not beneficial. If the MCE supports using RIP directly
+ // do it, otherwise fallback to absolute (this is determined by IsPCRel).
+ // 89 05 00 00 00 00 mov %eax,0(%rip) # PC-relative
+ // 89 04 25 00 00 00 00 mov %eax,0x0 # Absolute
+ bool Indirect = gvNeedsNonLazyPtr(*RelocOp, TM);
+ emitGlobalAddress(RelocOp->getGlobal(), RelocType, RelocOp->getOffset(),
+ Adj, Indirect);
+ } else if (RelocOp->isSymbol()) {
+ emitExternalSymbolAddress(RelocOp->getSymbolName(), RelocType);
+ } else if (RelocOp->isCPI()) {
+ emitConstPoolAddress(RelocOp->getIndex(), RelocType,
+ RelocOp->getOffset(), Adj);
+ } else {
+ assert(RelocOp->isJTI() && "Unexpected machine operand!");
+ emitJumpTableAddress(RelocOp->getIndex(), RelocType, Adj);
+ }
+}
+
+template<class CodeEmitter>
+void Emitter<CodeEmitter>::emitMemModRMByte(const MachineInstr &MI,
+ unsigned Op,unsigned RegOpcodeField,
+ intptr_t PCAdj) {
+ const MachineOperand &Op3 = MI.getOperand(Op+3);
+ int DispVal = 0;
+ const MachineOperand *DispForReloc = 0;
+
+ // Figure out what sort of displacement we have to handle here.
+ if (Op3.isGlobal()) {
+ DispForReloc = &Op3;
+ } else if (Op3.isSymbol()) {
+ DispForReloc = &Op3;
+ } else if (Op3.isCPI()) {
+ if (!MCE.earlyResolveAddresses() || Is64BitMode || IsPIC) {
+ DispForReloc = &Op3;
+ } else {
+ DispVal += MCE.getConstantPoolEntryAddress(Op3.getIndex());
+ DispVal += Op3.getOffset();
+ }
+ } else if (Op3.isJTI()) {
+ if (!MCE.earlyResolveAddresses() || Is64BitMode || IsPIC) {
+ DispForReloc = &Op3;
+ } else {
+ DispVal += MCE.getJumpTableEntryAddress(Op3.getIndex());
+ }
+ } else {
+ DispVal = Op3.getImm();
+ }
+
+ const MachineOperand &Base = MI.getOperand(Op);
+ const MachineOperand &Scale = MI.getOperand(Op+1);
+ const MachineOperand &IndexReg = MI.getOperand(Op+2);
+
+ unsigned BaseReg = Base.getReg();
+
+ // Handle %rip relative addressing.
+ if (BaseReg == X86::RIP ||
+ (Is64BitMode && DispForReloc)) { // [disp32+RIP] in X86-64 mode
+ assert(IndexReg.getReg() == 0 && Is64BitMode &&
+ "Invalid rip-relative address");
+ MCE.emitByte(ModRMByte(0, RegOpcodeField, 5));
+ emitDisplacementField(DispForReloc, DispVal, PCAdj, true);
+ return;
+ }
+
+ // Indicate that the displacement will use an pcrel or absolute reference
+ // by default. MCEs able to resolve addresses on-the-fly use pcrel by default
+ // while others, unless explicit asked to use RIP, use absolute references.
+ bool IsPCRel = MCE.earlyResolveAddresses() ? true : false;
+
+ // Is a SIB byte needed?
+ // If no BaseReg, issue a RIP relative instruction only if the MCE can
+ // resolve addresses on-the-fly, otherwise use SIB (Intel Manual 2A, table
+ // 2-7) and absolute references.
+ unsigned BaseRegNo = -1U;
+ if (BaseReg != 0 && BaseReg != X86::RIP)
+ BaseRegNo = getX86RegNum(BaseReg);
+
+ if (// The SIB byte must be used if there is an index register.
+ IndexReg.getReg() == 0 &&
+ // The SIB byte must be used if the base is ESP/RSP/R12, all of which
+ // encode to an R/M value of 4, which indicates that a SIB byte is
+ // present.
+ BaseRegNo != N86::ESP &&
+ // If there is no base register and we're in 64-bit mode, we need a SIB
+ // byte to emit an addr that is just 'disp32' (the non-RIP relative form).
+ (!Is64BitMode || BaseReg != 0)) {
+ if (BaseReg == 0 || // [disp32] in X86-32 mode
+ BaseReg == X86::RIP) { // [disp32+RIP] in X86-64 mode
+ MCE.emitByte(ModRMByte(0, RegOpcodeField, 5));
+ emitDisplacementField(DispForReloc, DispVal, PCAdj, true);
+ return;
+ }
+
+ // If the base is not EBP/ESP and there is no displacement, use simple
+ // indirect register encoding, this handles addresses like [EAX]. The
+ // encoding for [EBP] with no displacement means [disp32] so we handle it
+ // by emitting a displacement of 0 below.
+ if (!DispForReloc && DispVal == 0 && BaseRegNo != N86::EBP) {
+ MCE.emitByte(ModRMByte(0, RegOpcodeField, BaseRegNo));
+ return;
+ }
+
+ // Otherwise, if the displacement fits in a byte, encode as [REG+disp8].
+ if (!DispForReloc && isDisp8(DispVal)) {
+ MCE.emitByte(ModRMByte(1, RegOpcodeField, BaseRegNo));
+ emitConstant(DispVal, 1);
+ return;
+ }
+
+ // Otherwise, emit the most general non-SIB encoding: [REG+disp32]
+ MCE.emitByte(ModRMByte(2, RegOpcodeField, BaseRegNo));
+ emitDisplacementField(DispForReloc, DispVal, PCAdj, IsPCRel);
+ return;
+ }
+
+ // Otherwise we need a SIB byte, so start by outputting the ModR/M byte first.
+ assert(IndexReg.getReg() != X86::ESP &&
+ IndexReg.getReg() != X86::RSP && "Cannot use ESP as index reg!");
+
+ bool ForceDisp32 = false;
+ bool ForceDisp8 = false;
+ if (BaseReg == 0) {
+ // If there is no base register, we emit the special case SIB byte with
+ // MOD=0, BASE=4, to JUST get the index, scale, and displacement.
+ MCE.emitByte(ModRMByte(0, RegOpcodeField, 4));
+ ForceDisp32 = true;
+ } else if (DispForReloc) {
+ // Emit the normal disp32 encoding.
+ MCE.emitByte(ModRMByte(2, RegOpcodeField, 4));
+ ForceDisp32 = true;
+ } else if (DispVal == 0 && BaseRegNo != N86::EBP) {
+ // Emit no displacement ModR/M byte
+ MCE.emitByte(ModRMByte(0, RegOpcodeField, 4));
+ } else if (isDisp8(DispVal)) {
+ // Emit the disp8 encoding...
+ MCE.emitByte(ModRMByte(1, RegOpcodeField, 4));
+ ForceDisp8 = true; // Make sure to force 8 bit disp if Base=EBP
+ } else {
+ // Emit the normal disp32 encoding...
+ MCE.emitByte(ModRMByte(2, RegOpcodeField, 4));
+ }
+
+ // Calculate what the SS field value should be...
+ static const unsigned SSTable[] = { ~0, 0, 1, ~0, 2, ~0, ~0, ~0, 3 };
+ unsigned SS = SSTable[Scale.getImm()];
+
+ if (BaseReg == 0) {
+ // Handle the SIB byte for the case where there is no base, see Intel
+ // Manual 2A, table 2-7. The displacement has already been output.
+ unsigned IndexRegNo;
+ if (IndexReg.getReg())
+ IndexRegNo = getX86RegNum(IndexReg.getReg());
+ else // Examples: [ESP+1*<noreg>+4] or [scaled idx]+disp32 (MOD=0,BASE=5)
+ IndexRegNo = 4;
+ emitSIBByte(SS, IndexRegNo, 5);
+ } else {
+ unsigned BaseRegNo = getX86RegNum(BaseReg);
+ unsigned IndexRegNo;
+ if (IndexReg.getReg())
+ IndexRegNo = getX86RegNum(IndexReg.getReg());
+ else
+ IndexRegNo = 4; // For example [ESP+1*<noreg>+4]
+ emitSIBByte(SS, IndexRegNo, BaseRegNo);
+ }
+
+ // Do we need to output a displacement?
+ if (ForceDisp8) {
+ emitConstant(DispVal, 1);
+ } else if (DispVal != 0 || ForceDisp32) {
+ emitDisplacementField(DispForReloc, DispVal, PCAdj, IsPCRel);
+ }
+}
+
+template<class CodeEmitter>
+void Emitter<CodeEmitter>::emitInstruction(const MachineInstr &MI,
+ const TargetInstrDesc *Desc) {
+ DEBUG(dbgs() << MI);
+
+ MCE.processDebugLoc(MI.getDebugLoc(), true);
+
+ unsigned Opcode = Desc->Opcode;
+
+ // Emit the lock opcode prefix as needed.
+ if (Desc->TSFlags & X86II::LOCK)
+ MCE.emitByte(0xF0);
+
+ // Emit segment override opcode prefix as needed.
+ switch (Desc->TSFlags & X86II::SegOvrMask) {
+ case X86II::FS:
+ MCE.emitByte(0x64);
+ break;
+ case X86II::GS:
+ MCE.emitByte(0x65);
+ break;
+ default: llvm_unreachable("Invalid segment!");
+ case 0: break; // No segment override!
+ }
+
+ // Emit the repeat opcode prefix as needed.
+ if ((Desc->TSFlags & X86II::Op0Mask) == X86II::REP)
+ MCE.emitByte(0xF3);
+
+ // Emit the operand size opcode prefix as needed.
+ if (Desc->TSFlags & X86II::OpSize)
+ MCE.emitByte(0x66);
+
+ // Emit the address size opcode prefix as needed.
+ if (Desc->TSFlags & X86II::AdSize)
+ MCE.emitByte(0x67);
+
+ bool Need0FPrefix = false;
+ switch (Desc->TSFlags & X86II::Op0Mask) {
+ case X86II::TB: // Two-byte opcode prefix
+ case X86II::T8: // 0F 38
+ case X86II::TA: // 0F 3A
+ Need0FPrefix = true;
+ break;
+ case X86II::TF: // F2 0F 38
+ MCE.emitByte(0xF2);
+ Need0FPrefix = true;
+ break;
+ case X86II::REP: break; // already handled.
+ case X86II::XS: // F3 0F
+ MCE.emitByte(0xF3);
+ Need0FPrefix = true;
+ break;
+ case X86II::XD: // F2 0F
+ MCE.emitByte(0xF2);
+ Need0FPrefix = true;
+ break;
+ case X86II::D8: case X86II::D9: case X86II::DA: case X86II::DB:
+ case X86II::DC: case X86II::DD: case X86II::DE: case X86II::DF:
+ MCE.emitByte(0xD8+
+ (((Desc->TSFlags & X86II::Op0Mask)-X86II::D8)
+ >> X86II::Op0Shift));
+ break; // Two-byte opcode prefix
+ default: llvm_unreachable("Invalid prefix!");
+ case 0: break; // No prefix!
+ }
+
+ // Handle REX prefix.
+ if (Is64BitMode) {
+ if (unsigned REX = X86InstrInfo::determineREX(MI))
+ MCE.emitByte(0x40 | REX);
+ }
+
+ // 0x0F escape code must be emitted just before the opcode.
+ if (Need0FPrefix)
+ MCE.emitByte(0x0F);
+
+ switch (Desc->TSFlags & X86II::Op0Mask) {
+ case X86II::TF: // F2 0F 38
+ case X86II::T8: // 0F 38
+ MCE.emitByte(0x38);
+ break;
+ case X86II::TA: // 0F 3A
+ MCE.emitByte(0x3A);
+ break;
+ }
+
+ // If this is a two-address instruction, skip one of the register operands.
+ unsigned NumOps = Desc->getNumOperands();
+ unsigned CurOp = 0;
+ if (NumOps > 1 && Desc->getOperandConstraint(1, TOI::TIED_TO) != -1)
+ ++CurOp;
+ else if (NumOps > 2 && Desc->getOperandConstraint(NumOps-1, TOI::TIED_TO)== 0)
+ // Skip the last source operand that is tied_to the dest reg. e.g. LXADD32
+ --NumOps;
+
+ unsigned char BaseOpcode = X86II::getBaseOpcodeFor(Desc->TSFlags);
+ switch (Desc->TSFlags & X86II::FormMask) {
+ default:
+ llvm_unreachable("Unknown FormMask value in X86 MachineCodeEmitter!");
+ case X86II::Pseudo:
+ // Remember the current PC offset, this is the PIC relocation
+ // base address.
+ switch (Opcode) {
+ default:
+ llvm_unreachable("psuedo instructions should be removed before code"
+ " emission");
+ break;
+ case TargetOpcode::INLINEASM:
+ // We allow inline assembler nodes with empty bodies - they can
+ // implicitly define registers, which is ok for JIT.
+ if (MI.getOperand(0).getSymbolName()[0])
+ report_fatal_error("JIT does not support inline asm!");
+ break;
+ case TargetOpcode::DBG_LABEL:
+ case TargetOpcode::GC_LABEL:
+ case TargetOpcode::EH_LABEL:
+ MCE.emitLabel(MI.getOperand(0).getMCSymbol());
+ break;
+
+ case TargetOpcode::IMPLICIT_DEF:
+ case TargetOpcode::KILL:
+ case X86::FP_REG_KILL:
+ break;
+ case X86::MOVPC32r: {
+ // This emits the "call" portion of this pseudo instruction.
+ MCE.emitByte(BaseOpcode);
+ emitConstant(0, X86II::getSizeOfImm(Desc->TSFlags));
+ // Remember PIC base.
+ PICBaseOffset = (intptr_t) MCE.getCurrentPCOffset();
+ X86JITInfo *JTI = TM.getJITInfo();
+ JTI->setPICBase(MCE.getCurrentPCValue());
+ break;
+ }
+ }
+ CurOp = NumOps;
+ break;
+ case X86II::RawFrm: {
+ MCE.emitByte(BaseOpcode);
+
+ if (CurOp == NumOps)
+ break;
+
+ const MachineOperand &MO = MI.getOperand(CurOp++);
+
+ DEBUG(dbgs() << "RawFrm CurOp " << CurOp << "\n");
+ DEBUG(dbgs() << "isMBB " << MO.isMBB() << "\n");
+ DEBUG(dbgs() << "isGlobal " << MO.isGlobal() << "\n");
+ DEBUG(dbgs() << "isSymbol " << MO.isSymbol() << "\n");
+ DEBUG(dbgs() << "isImm " << MO.isImm() << "\n");
+
+ if (MO.isMBB()) {
+ emitPCRelativeBlockAddress(MO.getMBB());
+ break;
+ }
+
+ if (MO.isGlobal()) {
+ emitGlobalAddress(MO.getGlobal(), X86::reloc_pcrel_word,
+ MO.getOffset(), 0);
+ break;
+ }
+
+ if (MO.isSymbol()) {
+ emitExternalSymbolAddress(MO.getSymbolName(), X86::reloc_pcrel_word);
+ break;
+ }
+
+ // FIXME: Only used by hackish MCCodeEmitter, remove when dead.
+ if (MO.isJTI()) {
+ emitJumpTableAddress(MO.getIndex(), X86::reloc_pcrel_word);
+ break;
+ }
+
+ assert(MO.isImm() && "Unknown RawFrm operand!");
+ if (Opcode == X86::CALLpcrel32 || Opcode == X86::CALL64pcrel32) {
+ // Fix up immediate operand for pc relative calls.
+ intptr_t Imm = (intptr_t)MO.getImm();
+ Imm = Imm - MCE.getCurrentPCValue() - 4;
+ emitConstant(Imm, X86II::getSizeOfImm(Desc->TSFlags));
+ } else
+ emitConstant(MO.getImm(), X86II::getSizeOfImm(Desc->TSFlags));
+ break;
+ }
+
+ case X86II::AddRegFrm: {
+ MCE.emitByte(BaseOpcode + getX86RegNum(MI.getOperand(CurOp++).getReg()));
+
+ if (CurOp == NumOps)
+ break;
+
+ const MachineOperand &MO1 = MI.getOperand(CurOp++);
+ unsigned Size = X86II::getSizeOfImm(Desc->TSFlags);
+ if (MO1.isImm()) {
+ emitConstant(MO1.getImm(), Size);
+ break;
+ }
+
+ unsigned rt = Is64BitMode ? X86::reloc_pcrel_word
+ : (IsPIC ? X86::reloc_picrel_word : X86::reloc_absolute_word);
+ if (Opcode == X86::MOV64ri64i32)
+ rt = X86::reloc_absolute_word; // FIXME: add X86II flag?
+ // This should not occur on Darwin for relocatable objects.
+ if (Opcode == X86::MOV64ri)
+ rt = X86::reloc_absolute_dword; // FIXME: add X86II flag?
+ if (MO1.isGlobal()) {
+ bool Indirect = gvNeedsNonLazyPtr(MO1, TM);
+ emitGlobalAddress(MO1.getGlobal(), rt, MO1.getOffset(), 0,
+ Indirect);
+ } else if (MO1.isSymbol())
+ emitExternalSymbolAddress(MO1.getSymbolName(), rt);
+ else if (MO1.isCPI())
+ emitConstPoolAddress(MO1.getIndex(), rt);
+ else if (MO1.isJTI())
+ emitJumpTableAddress(MO1.getIndex(), rt);
+ break;
+ }
+
+ case X86II::MRMDestReg: {
+ MCE.emitByte(BaseOpcode);
+ emitRegModRMByte(MI.getOperand(CurOp).getReg(),
+ getX86RegNum(MI.getOperand(CurOp+1).getReg()));
+ CurOp += 2;
+ if (CurOp != NumOps)
+ emitConstant(MI.getOperand(CurOp++).getImm(),
+ X86II::getSizeOfImm(Desc->TSFlags));
+ break;
+ }
+ case X86II::MRMDestMem: {
+ MCE.emitByte(BaseOpcode);
+ emitMemModRMByte(MI, CurOp,
+ getX86RegNum(MI.getOperand(CurOp + X86AddrNumOperands)
+ .getReg()));
+ CurOp += X86AddrNumOperands + 1;
+ if (CurOp != NumOps)
+ emitConstant(MI.getOperand(CurOp++).getImm(),
+ X86II::getSizeOfImm(Desc->TSFlags));
+ break;
+ }
+
+ case X86II::MRMSrcReg:
+ MCE.emitByte(BaseOpcode);
+ emitRegModRMByte(MI.getOperand(CurOp+1).getReg(),
+ getX86RegNum(MI.getOperand(CurOp).getReg()));
+ CurOp += 2;
+ if (CurOp != NumOps)
+ emitConstant(MI.getOperand(CurOp++).getImm(),
+ X86II::getSizeOfImm(Desc->TSFlags));
+ break;
+
+ case X86II::MRMSrcMem: {
+ // FIXME: Maybe lea should have its own form?
+ int AddrOperands;
+ if (Opcode == X86::LEA64r || Opcode == X86::LEA64_32r ||
+ Opcode == X86::LEA16r || Opcode == X86::LEA32r)
+ AddrOperands = X86AddrNumOperands - 1; // No segment register
+ else
+ AddrOperands = X86AddrNumOperands;
+
+ intptr_t PCAdj = (CurOp + AddrOperands + 1 != NumOps) ?
+ X86II::getSizeOfImm(Desc->TSFlags) : 0;
+
+ MCE.emitByte(BaseOpcode);
+ emitMemModRMByte(MI, CurOp+1, getX86RegNum(MI.getOperand(CurOp).getReg()),
+ PCAdj);
+ CurOp += AddrOperands + 1;
+ if (CurOp != NumOps)
+ emitConstant(MI.getOperand(CurOp++).getImm(),
+ X86II::getSizeOfImm(Desc->TSFlags));
+ break;
+ }
+
+ case X86II::MRM0r: case X86II::MRM1r:
+ case X86II::MRM2r: case X86II::MRM3r:
+ case X86II::MRM4r: case X86II::MRM5r:
+ case X86II::MRM6r: case X86II::MRM7r: {
+ MCE.emitByte(BaseOpcode);
+ emitRegModRMByte(MI.getOperand(CurOp++).getReg(),
+ (Desc->TSFlags & X86II::FormMask)-X86II::MRM0r);
+
+ if (CurOp == NumOps)
+ break;
+
+ const MachineOperand &MO1 = MI.getOperand(CurOp++);
+ unsigned Size = X86II::getSizeOfImm(Desc->TSFlags);
+ if (MO1.isImm()) {
+ emitConstant(MO1.getImm(), Size);
+ break;
+ }
+
+ unsigned rt = Is64BitMode ? X86::reloc_pcrel_word
+ : (IsPIC ? X86::reloc_picrel_word : X86::reloc_absolute_word);
+ if (Opcode == X86::MOV64ri32)
+ rt = X86::reloc_absolute_word_sext; // FIXME: add X86II flag?
+ if (MO1.isGlobal()) {
+ bool Indirect = gvNeedsNonLazyPtr(MO1, TM);
+ emitGlobalAddress(MO1.getGlobal(), rt, MO1.getOffset(), 0,
+ Indirect);
+ } else if (MO1.isSymbol())
+ emitExternalSymbolAddress(MO1.getSymbolName(), rt);
+ else if (MO1.isCPI())
+ emitConstPoolAddress(MO1.getIndex(), rt);
+ else if (MO1.isJTI())
+ emitJumpTableAddress(MO1.getIndex(), rt);
+ break;
+ }
+
+ case X86II::MRM0m: case X86II::MRM1m:
+ case X86II::MRM2m: case X86II::MRM3m:
+ case X86II::MRM4m: case X86II::MRM5m:
+ case X86II::MRM6m: case X86II::MRM7m: {
+ intptr_t PCAdj = (CurOp + X86AddrNumOperands != NumOps) ?
+ (MI.getOperand(CurOp+X86AddrNumOperands).isImm() ?
+ X86II::getSizeOfImm(Desc->TSFlags) : 4) : 0;
+
+ MCE.emitByte(BaseOpcode);
+ emitMemModRMByte(MI, CurOp, (Desc->TSFlags & X86II::FormMask)-X86II::MRM0m,
+ PCAdj);
+ CurOp += X86AddrNumOperands;
+
+ if (CurOp == NumOps)
+ break;
+
+ const MachineOperand &MO = MI.getOperand(CurOp++);
+ unsigned Size = X86II::getSizeOfImm(Desc->TSFlags);
+ if (MO.isImm()) {
+ emitConstant(MO.getImm(), Size);
+ break;
+ }
+
+ unsigned rt = Is64BitMode ? X86::reloc_pcrel_word
+ : (IsPIC ? X86::reloc_picrel_word : X86::reloc_absolute_word);
+ if (Opcode == X86::MOV64mi32)
+ rt = X86::reloc_absolute_word_sext; // FIXME: add X86II flag?
+ if (MO.isGlobal()) {
+ bool Indirect = gvNeedsNonLazyPtr(MO, TM);
+ emitGlobalAddress(MO.getGlobal(), rt, MO.getOffset(), 0,
+ Indirect);
+ } else if (MO.isSymbol())
+ emitExternalSymbolAddress(MO.getSymbolName(), rt);
+ else if (MO.isCPI())
+ emitConstPoolAddress(MO.getIndex(), rt);
+ else if (MO.isJTI())
+ emitJumpTableAddress(MO.getIndex(), rt);
+ break;
+ }
+
+ case X86II::MRMInitReg:
+ MCE.emitByte(BaseOpcode);
+ // Duplicate register, used by things like MOV8r0 (aka xor reg,reg).
+ emitRegModRMByte(MI.getOperand(CurOp).getReg(),
+ getX86RegNum(MI.getOperand(CurOp).getReg()));
+ ++CurOp;
+ break;
+
+ case X86II::MRM_C1:
+ MCE.emitByte(BaseOpcode);
+ MCE.emitByte(0xC1);
+ break;
+ case X86II::MRM_C8:
+ MCE.emitByte(BaseOpcode);
+ MCE.emitByte(0xC8);
+ break;
+ case X86II::MRM_C9:
+ MCE.emitByte(BaseOpcode);
+ MCE.emitByte(0xC9);
+ break;
+ case X86II::MRM_E8:
+ MCE.emitByte(BaseOpcode);
+ MCE.emitByte(0xE8);
+ break;
+ case X86II::MRM_F0:
+ MCE.emitByte(BaseOpcode);
+ MCE.emitByte(0xF0);
+ break;
+ }
+
+ if (!Desc->isVariadic() && CurOp != NumOps) {
+#ifndef NDEBUG
+ dbgs() << "Cannot encode all operands of: " << MI << "\n";
+#endif
+ llvm_unreachable(0);
+ }
+
+ MCE.processDebugLoc(MI.getDebugLoc(), false);
+}
generated by cgit v1.2.3 (git 2.25.1) at 2025-11-04 09:39:20 +0000