//===-- X86AsmPrinter.cpp - Convert X86 LLVM code to AT&T assembly --------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This file contains a printer that converts from our internal representation // of machine-dependent LLVM code to X86 machine code. // //===----------------------------------------------------------------------===// #include "X86AsmPrinter.h" #include "InstPrinter/X86ATTInstPrinter.h" #include "MCTargetDesc/X86BaseInfo.h" #include "X86InstrInfo.h" #include "X86MachineFunctionInfo.h" #include "llvm/ADT/SmallString.h" #include "llvm/CodeGen/MachineConstantPool.h" #include "llvm/CodeGen/MachineModuleInfoImpls.h" #include "llvm/CodeGen/MachineValueType.h" #include "llvm/CodeGen/TargetLoweringObjectFileImpl.h" #include "llvm/IR/DebugInfo.h" #include "llvm/IR/DerivedTypes.h" #include "llvm/IR/Mangler.h" #include "llvm/IR/Module.h" #include "llvm/IR/Type.h" #include "llvm/MC/MCAsmInfo.h" #include "llvm/MC/MCContext.h" #include "llvm/MC/MCExpr.h" #include "llvm/MC/MCSectionCOFF.h" #include "llvm/MC/MCSectionMachO.h" #include "llvm/MC/MCStreamer.h" #include "llvm/MC/MCSymbol.h" #include "llvm/Support/COFF.h" #include "llvm/Support/Debug.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/TargetRegistry.h" using namespace llvm; //===----------------------------------------------------------------------===// // Primitive Helper Functions. //===----------------------------------------------------------------------===// /// runOnMachineFunction - Emit the function body. /// bool X86AsmPrinter::runOnMachineFunction(MachineFunction &MF) { Subtarget = &MF.getSubtarget<X86Subtarget>(); SMShadowTracker.startFunction(MF); SetupMachineFunction(MF); if (Subtarget->isTargetCOFF()) { bool Intrn = MF.getFunction()->hasInternalLinkage(); OutStreamer.BeginCOFFSymbolDef(CurrentFnSym); OutStreamer.EmitCOFFSymbolStorageClass(Intrn ? COFF::IMAGE_SYM_CLASS_STATIC : COFF::IMAGE_SYM_CLASS_EXTERNAL); OutStreamer.EmitCOFFSymbolType(COFF::IMAGE_SYM_DTYPE_FUNCTION << COFF::SCT_COMPLEX_TYPE_SHIFT); OutStreamer.EndCOFFSymbolDef(); } // Emit the rest of the function body. EmitFunctionBody(); // We didn't modify anything. return false; } /// printSymbolOperand - Print a raw symbol reference operand. This handles /// jump tables, constant pools, global address and external symbols, all of /// which print to a label with various suffixes for relocation types etc. static void printSymbolOperand(X86AsmPrinter &P, const MachineOperand &MO, raw_ostream &O) { switch (MO.getType()) { default: llvm_unreachable("unknown symbol type!"); case MachineOperand::MO_ConstantPoolIndex: O << *P.GetCPISymbol(MO.getIndex()); P.printOffset(MO.getOffset(), O); break; case MachineOperand::MO_GlobalAddress: { const GlobalValue *GV = MO.getGlobal(); MCSymbol *GVSym; if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB) GVSym = P.getSymbolWithGlobalValueBase(GV, "$stub"); else if (MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY || MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY_PIC_BASE || MO.getTargetFlags() == X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE) GVSym = P.getSymbolWithGlobalValueBase(GV, "$non_lazy_ptr"); else GVSym = P.getSymbol(GV); // Handle dllimport linkage. if (MO.getTargetFlags() == X86II::MO_DLLIMPORT) GVSym = P.OutContext.GetOrCreateSymbol(Twine("__imp_") + GVSym->getName()); if (MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY || MO.getTargetFlags() == X86II::MO_DARWIN_NONLAZY_PIC_BASE) { MCSymbol *Sym = P.getSymbolWithGlobalValueBase(GV, "$non_lazy_ptr"); MachineModuleInfoImpl::StubValueTy &StubSym = P.MMI->getObjFileInfo<MachineModuleInfoMachO>().getGVStubEntry(Sym); if (!StubSym.getPointer()) StubSym = MachineModuleInfoImpl:: StubValueTy(P.getSymbol(GV), !GV->hasInternalLinkage()); } else if (MO.getTargetFlags() == X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE){ MCSymbol *Sym = P.getSymbolWithGlobalValueBase(GV, "$non_lazy_ptr"); MachineModuleInfoImpl::StubValueTy &StubSym = P.MMI->getObjFileInfo<MachineModuleInfoMachO>().getHiddenGVStubEntry( Sym); if (!StubSym.getPointer()) StubSym = MachineModuleInfoImpl:: StubValueTy(P.getSymbol(GV), !GV->hasInternalLinkage()); } else if (MO.getTargetFlags() == X86II::MO_DARWIN_STUB) { MCSymbol *Sym = P.getSymbolWithGlobalValueBase(GV, "$stub"); MachineModuleInfoImpl::StubValueTy &StubSym = P.MMI->getObjFileInfo<MachineModuleInfoMachO>().getFnStubEntry(Sym); if (!StubSym.getPointer()) StubSym = MachineModuleInfoImpl:: StubValueTy(P.getSymbol(GV), !GV->hasInternalLinkage()); } // If the name begins with a dollar-sign, enclose it in parens. We do this // to avoid having it look like an integer immediate to the assembler. if (GVSym->getName()[0] != '$') O << *GVSym; else O << '(' << *GVSym << ')'; P.printOffset(MO.getOffset(), O); break; } } switch (MO.getTargetFlags()) { default: llvm_unreachable("Unknown target flag on GV operand"); case X86II::MO_NO_FLAG: // No flag. break; case X86II::MO_DARWIN_NONLAZY: case X86II::MO_DLLIMPORT: case X86II::MO_DARWIN_STUB: // These affect the name of the symbol, not any suffix. break; case X86II::MO_GOT_ABSOLUTE_ADDRESS: O << " + [.-" << *P.MF->getPICBaseSymbol() << ']'; break; case X86II::MO_PIC_BASE_OFFSET: case X86II::MO_DARWIN_NONLAZY_PIC_BASE: case X86II::MO_DARWIN_HIDDEN_NONLAZY_PIC_BASE: O << '-' << *P.MF->getPICBaseSymbol(); break; case X86II::MO_TLSGD: O << "@TLSGD"; break; case X86II::MO_TLSLD: O << "@TLSLD"; break; case X86II::MO_TLSLDM: O << "@TLSLDM"; break; case X86II::MO_GOTTPOFF: O << "@GOTTPOFF"; break; case X86II::MO_INDNTPOFF: O << "@INDNTPOFF"; break; case X86II::MO_TPOFF: O << "@TPOFF"; break; case X86II::MO_DTPOFF: O << "@DTPOFF"; break; case X86II::MO_NTPOFF: O << "@NTPOFF"; break; case X86II::MO_GOTNTPOFF: O << "@GOTNTPOFF"; break; case X86II::MO_GOTPCREL: O << "@GOTPCREL"; break; case X86II::MO_GOT: O << "@GOT"; break; case X86II::MO_GOTOFF: O << "@GOTOFF"; break; case X86II::MO_PLT: O << "@PLT"; break; case X86II::MO_TLVP: O << "@TLVP"; break; case X86II::MO_TLVP_PIC_BASE: O << "@TLVP" << '-' << *P.MF->getPICBaseSymbol(); break; case X86II::MO_SECREL: O << "@SECREL32"; break; } } static void printOperand(X86AsmPrinter &P, const MachineInstr *MI, unsigned OpNo, raw_ostream &O, const char *Modifier = nullptr, unsigned AsmVariant = 0); /// printPCRelImm - This is used to print an immediate value that ends up /// being encoded as a pc-relative value. These print slightly differently, for /// example, a $ is not emitted. static void printPCRelImm(X86AsmPrinter &P, const MachineInstr *MI, unsigned OpNo, raw_ostream &O) { const MachineOperand &MO = MI->getOperand(OpNo); switch (MO.getType()) { default: llvm_unreachable("Unknown pcrel immediate operand"); case MachineOperand::MO_Register: // pc-relativeness was handled when computing the value in the reg. printOperand(P, MI, OpNo, O); return; case MachineOperand::MO_Immediate: O << MO.getImm(); return; case MachineOperand::MO_GlobalAddress: printSymbolOperand(P, MO, O); return; } } static void printOperand(X86AsmPrinter &P, const MachineInstr *MI, unsigned OpNo, raw_ostream &O, const char *Modifier, unsigned AsmVariant) { const MachineOperand &MO = MI->getOperand(OpNo); switch (MO.getType()) { default: llvm_unreachable("unknown operand type!"); case MachineOperand::MO_Register: { // FIXME: Enumerating AsmVariant, so we can remove magic number. if (AsmVariant == 0) O << '%'; unsigned Reg = MO.getReg(); if (Modifier && strncmp(Modifier, "subreg", strlen("subreg")) == 0) { MVT::SimpleValueType VT = (strcmp(Modifier+6,"64") == 0) ? MVT::i64 : ((strcmp(Modifier+6, "32") == 0) ? MVT::i32 : ((strcmp(Modifier+6,"16") == 0) ? MVT::i16 : MVT::i8)); Reg = getX86SubSuperRegister(Reg, VT); } O << X86ATTInstPrinter::getRegisterName(Reg); return; } case MachineOperand::MO_Immediate: if (AsmVariant == 0) O << '$'; O << MO.getImm(); return; case MachineOperand::MO_GlobalAddress: { if (AsmVariant == 0) O << '$'; printSymbolOperand(P, MO, O); break; } } } static void printLeaMemReference(X86AsmPrinter &P, const MachineInstr *MI, unsigned Op, raw_ostream &O, const char *Modifier = nullptr) { const MachineOperand &BaseReg = MI->getOperand(Op+X86::AddrBaseReg); const MachineOperand &IndexReg = MI->getOperand(Op+X86::AddrIndexReg); const MachineOperand &DispSpec = MI->getOperand(Op+X86::AddrDisp); // If we really don't want to print out (rip), don't. bool HasBaseReg = BaseReg.getReg() != 0; if (HasBaseReg && Modifier && !strcmp(Modifier, "no-rip") && BaseReg.getReg() == X86::RIP) HasBaseReg = false; // HasParenPart - True if we will print out the () part of the mem ref. bool HasParenPart = IndexReg.getReg() || HasBaseReg; switch (DispSpec.getType()) { default: llvm_unreachable("unknown operand type!"); case MachineOperand::MO_Immediate: { int DispVal = DispSpec.getImm(); if (DispVal || !HasParenPart) O << DispVal; break; } case MachineOperand::MO_GlobalAddress: case MachineOperand::MO_ConstantPoolIndex: printSymbolOperand(P, DispSpec, O); } if (Modifier && strcmp(Modifier, "H") == 0) O << "+8"; if (HasParenPart) { assert(IndexReg.getReg() != X86::ESP && "X86 doesn't allow scaling by ESP"); O << '('; if (HasBaseReg) printOperand(P, MI, Op+X86::AddrBaseReg, O, Modifier); if (IndexReg.getReg()) { O << ','; printOperand(P, MI, Op+X86::AddrIndexReg, O, Modifier); unsigned ScaleVal = MI->getOperand(Op+X86::AddrScaleAmt).getImm(); if (ScaleVal != 1) O << ',' << ScaleVal; } O << ')'; } } static void printMemReference(X86AsmPrinter &P, const MachineInstr *MI, unsigned Op, raw_ostream &O, const char *Modifier = nullptr) { assert(isMem(MI, Op) && "Invalid memory reference!"); const MachineOperand &Segment = MI->getOperand(Op+X86::AddrSegmentReg); if (Segment.getReg()) { printOperand(P, MI, Op+X86::AddrSegmentReg, O, Modifier); O << ':'; } printLeaMemReference(P, MI, Op, O, Modifier); } static void printIntelMemReference(X86AsmPrinter &P, const MachineInstr *MI, unsigned Op, raw_ostream &O, const char *Modifier = nullptr, unsigned AsmVariant = 1) { const MachineOperand &BaseReg = MI->getOperand(Op+X86::AddrBaseReg); unsigned ScaleVal = MI->getOperand(Op+X86::AddrScaleAmt).getImm(); const MachineOperand &IndexReg = MI->getOperand(Op+X86::AddrIndexReg); const MachineOperand &DispSpec = MI->getOperand(Op+X86::AddrDisp); const MachineOperand &SegReg = MI->getOperand(Op+X86::AddrSegmentReg); // If this has a segment register, print it. if (SegReg.getReg()) { printOperand(P, MI, Op+X86::AddrSegmentReg, O, Modifier, AsmVariant); O << ':'; } O << '['; bool NeedPlus = false; if (BaseReg.getReg()) { printOperand(P, MI, Op+X86::AddrBaseReg, O, Modifier, AsmVariant); NeedPlus = true; } if (IndexReg.getReg()) { if (NeedPlus) O << " + "; if (ScaleVal != 1) O << ScaleVal << '*'; printOperand(P, MI, Op+X86::AddrIndexReg, O, Modifier, AsmVariant); NeedPlus = true; } if (!DispSpec.isImm()) { if (NeedPlus) O << " + "; printOperand(P, MI, Op+X86::AddrDisp, O, Modifier, AsmVariant); } else { int64_t DispVal = DispSpec.getImm(); if (DispVal || (!IndexReg.getReg() && !BaseReg.getReg())) { if (NeedPlus) { if (DispVal > 0) O << " + "; else { O << " - "; DispVal = -DispVal; } } O << DispVal; } } O << ']'; } static bool printAsmMRegister(X86AsmPrinter &P, const MachineOperand &MO, char Mode, raw_ostream &O) { unsigned Reg = MO.getReg(); switch (Mode) { default: return true; // Unknown mode. case 'b': // Print QImode register Reg = getX86SubSuperRegister(Reg, MVT::i8); break; case 'h': // Print QImode high register Reg = getX86SubSuperRegister(Reg, MVT::i8, true); break; case 'w': // Print HImode register Reg = getX86SubSuperRegister(Reg, MVT::i16); break; case 'k': // Print SImode register Reg = getX86SubSuperRegister(Reg, MVT::i32); break; case 'q': // Print 64-bit register names if 64-bit integer registers are available. // Otherwise, print 32-bit register names. MVT::SimpleValueType Ty = P.getSubtarget().is64Bit() ? MVT::i64 : MVT::i32; Reg = getX86SubSuperRegister(Reg, Ty); break; } O << '%' << X86ATTInstPrinter::getRegisterName(Reg); return false; } /// PrintAsmOperand - Print out an operand for an inline asm expression. /// bool X86AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo, unsigned AsmVariant, const char *ExtraCode, raw_ostream &O) { // Does this asm operand have a single letter operand modifier? if (ExtraCode && ExtraCode[0]) { if (ExtraCode[1] != 0) return true; // Unknown modifier. const MachineOperand &MO = MI->getOperand(OpNo); switch (ExtraCode[0]) { default: // See if this is a generic print operand return AsmPrinter::PrintAsmOperand(MI, OpNo, AsmVariant, ExtraCode, O); case 'a': // This is an address. Currently only 'i' and 'r' are expected. switch (MO.getType()) { default: return true; case MachineOperand::MO_Immediate: O << MO.getImm(); return false; case MachineOperand::MO_ConstantPoolIndex: case MachineOperand::MO_JumpTableIndex: case MachineOperand::MO_ExternalSymbol: llvm_unreachable("unexpected operand type!"); case MachineOperand::MO_GlobalAddress: printSymbolOperand(*this, MO, O); if (Subtarget->isPICStyleRIPRel()) O << "(%rip)"; return false; case MachineOperand::MO_Register: O << '('; printOperand(*this, MI, OpNo, O); O << ')'; return false; } case 'c': // Don't print "$" before a global var name or constant. switch (MO.getType()) { default: printOperand(*this, MI, OpNo, O); break; case MachineOperand::MO_Immediate: O << MO.getImm(); break; case MachineOperand::MO_ConstantPoolIndex: case MachineOperand::MO_JumpTableIndex: case MachineOperand::MO_ExternalSymbol: llvm_unreachable("unexpected operand type!"); case MachineOperand::MO_GlobalAddress: printSymbolOperand(*this, MO, O); break; } return false; case 'A': // Print '*' before a register (it must be a register) if (MO.isReg()) { O << '*'; printOperand(*this, MI, OpNo, O); return false; } return true; case 'b': // Print QImode register case 'h': // Print QImode high register case 'w': // Print HImode register case 'k': // Print SImode register case 'q': // Print DImode register if (MO.isReg()) return printAsmMRegister(*this, MO, ExtraCode[0], O); printOperand(*this, MI, OpNo, O); return false; case 'P': // This is the operand of a call, treat specially. printPCRelImm(*this, MI, OpNo, O); return false; case 'n': // Negate the immediate or print a '-' before the operand. // Note: this is a temporary solution. It should be handled target // independently as part of the 'MC' work. if (MO.isImm()) { O << -MO.getImm(); return false; } O << '-'; } } printOperand(*this, MI, OpNo, O, /*Modifier*/ nullptr, AsmVariant); return false; } bool X86AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo, unsigned AsmVariant, const char *ExtraCode, raw_ostream &O) { if (AsmVariant) { printIntelMemReference(*this, MI, OpNo, O); return false; } if (ExtraCode && ExtraCode[0]) { if (ExtraCode[1] != 0) return true; // Unknown modifier. switch (ExtraCode[0]) { default: return true; // Unknown modifier. case 'b': // Print QImode register case 'h': // Print QImode high register case 'w': // Print HImode register case 'k': // Print SImode register case 'q': // Print SImode register // These only apply to registers, ignore on mem. break; case 'H': printMemReference(*this, MI, OpNo, O, "H"); return false; case 'P': // Don't print @PLT, but do print as memory. printMemReference(*this, MI, OpNo, O, "no-rip"); return false; } } printMemReference(*this, MI, OpNo, O); return false; } void X86AsmPrinter::EmitStartOfAsmFile(Module &M) { Triple TT(TM.getTargetTriple()); if (TT.isOSBinFormatMachO()) OutStreamer.SwitchSection(getObjFileLowering().getTextSection()); if (TT.isOSBinFormatCOFF()) { // Emit an absolute @feat.00 symbol. This appears to be some kind of // compiler features bitfield read by link.exe. if (TT.getArch() == Triple::x86) { MCSymbol *S = MMI->getContext().GetOrCreateSymbol(StringRef("@feat.00")); OutStreamer.BeginCOFFSymbolDef(S); OutStreamer.EmitCOFFSymbolStorageClass(COFF::IMAGE_SYM_CLASS_STATIC); OutStreamer.EmitCOFFSymbolType(COFF::IMAGE_SYM_DTYPE_NULL); OutStreamer.EndCOFFSymbolDef(); // According to the PE-COFF spec, the LSB of this value marks the object // for "registered SEH". This means that all SEH handler entry points // must be registered in .sxdata. Use of any unregistered handlers will // cause the process to terminate immediately. LLVM does not know how to // register any SEH handlers, so its object files should be safe. OutStreamer.EmitSymbolAttribute(S, MCSA_Global); OutStreamer.EmitAssignment( S, MCConstantExpr::Create(int64_t(1), MMI->getContext())); } } } static void emitNonLazySymbolPointer(MCStreamer &OutStreamer, MCSymbol *StubLabel, MachineModuleInfoImpl::StubValueTy &MCSym) { // L_foo$stub: OutStreamer.EmitLabel(StubLabel); // .indirect_symbol _foo OutStreamer.EmitSymbolAttribute(MCSym.getPointer(), MCSA_IndirectSymbol); if (MCSym.getInt()) // External to current translation unit. OutStreamer.EmitIntValue(0, 4/*size*/); else // Internal to current translation unit. // // When we place the LSDA into the TEXT section, the type info // pointers need to be indirect and pc-rel. We accomplish this by // using NLPs; however, sometimes the types are local to the file. // We need to fill in the value for the NLP in those cases. OutStreamer.EmitValue( MCSymbolRefExpr::Create(MCSym.getPointer(), OutStreamer.getContext()), 4 /*size*/); } MCSymbol *X86AsmPrinter::GetCPISymbol(unsigned CPID) const { if (Subtarget->isTargetKnownWindowsMSVC()) { const MachineConstantPoolEntry &CPE = MF->getConstantPool()->getConstants()[CPID]; if (!CPE.isMachineConstantPoolEntry()) { SectionKind Kind = CPE.getSectionKind(TM.getDataLayout()); const Constant *C = CPE.Val.ConstVal; if (const MCSectionCOFF *S = dyn_cast<MCSectionCOFF>( getObjFileLowering().getSectionForConstant(Kind, C))) { if (MCSymbol *Sym = S->getCOMDATSymbol()) { if (Sym->isUndefined()) OutStreamer.EmitSymbolAttribute(Sym, MCSA_Global); return Sym; } } } } return AsmPrinter::GetCPISymbol(CPID); } void X86AsmPrinter::GenerateExportDirective(const MCSymbol *Sym, bool IsData) { SmallString<128> Directive; raw_svector_ostream OS(Directive); StringRef Name = Sym->getName(); Triple TT(TM.getTargetTriple()); if (TT.isKnownWindowsMSVCEnvironment()) OS << " /EXPORT:"; else OS << " -export:"; if ((TT.isWindowsGNUEnvironment() || TT.isWindowsCygwinEnvironment()) && (Name[0] == getDataLayout().getGlobalPrefix())) Name = Name.drop_front(); OS << Name; if (IsData) { if (TT.isKnownWindowsMSVCEnvironment()) OS << ",DATA"; else OS << ",data"; } OS.flush(); OutStreamer.EmitBytes(Directive); } void X86AsmPrinter::EmitEndOfAsmFile(Module &M) { Triple TT(TM.getTargetTriple()); if (TT.isOSBinFormatMachO()) { // All darwin targets use mach-o. MachineModuleInfoMachO &MMIMacho = MMI->getObjFileInfo<MachineModuleInfoMachO>(); // Output stubs for dynamically-linked functions. MachineModuleInfoMachO::SymbolListTy Stubs; Stubs = MMIMacho.GetFnStubList(); if (!Stubs.empty()) { const MCSection *TheSection = OutContext.getMachOSection("__IMPORT", "__jump_table", MachO::S_SYMBOL_STUBS | MachO::S_ATTR_SELF_MODIFYING_CODE | MachO::S_ATTR_PURE_INSTRUCTIONS, 5, SectionKind::getMetadata()); OutStreamer.SwitchSection(TheSection); for (const auto &Stub : Stubs) { // L_foo$stub: OutStreamer.EmitLabel(Stub.first); // .indirect_symbol _foo OutStreamer.EmitSymbolAttribute(Stub.second.getPointer(), MCSA_IndirectSymbol); // hlt; hlt; hlt; hlt; hlt hlt = 0xf4. const char HltInsts[] = "\xf4\xf4\xf4\xf4\xf4"; OutStreamer.EmitBytes(StringRef(HltInsts, 5)); } Stubs.clear(); OutStreamer.AddBlankLine(); } // Output stubs for external and common global variables. Stubs = MMIMacho.GetGVStubList(); if (!Stubs.empty()) { const MCSection *TheSection = OutContext.getMachOSection("__IMPORT", "__pointers", MachO::S_NON_LAZY_SYMBOL_POINTERS, SectionKind::getMetadata()); OutStreamer.SwitchSection(TheSection); for (auto &Stub : Stubs) emitNonLazySymbolPointer(OutStreamer, Stub.first, Stub.second); Stubs.clear(); OutStreamer.AddBlankLine(); } Stubs = MMIMacho.GetHiddenGVStubList(); if (!Stubs.empty()) { const MCSection *TheSection = OutContext.getMachOSection("__IMPORT", "__pointers", MachO::S_NON_LAZY_SYMBOL_POINTERS, SectionKind::getMetadata()); OutStreamer.SwitchSection(TheSection); for (auto &Stub : Stubs) emitNonLazySymbolPointer(OutStreamer, Stub.first, Stub.second); Stubs.clear(); OutStreamer.AddBlankLine(); } SM.serializeToStackMapSection(); // Funny Darwin hack: This flag tells the linker that no global symbols // contain code that falls through to other global symbols (e.g. the obvious // implementation of multiple entry points). If this doesn't occur, the // linker can safely perform dead code stripping. Since LLVM never // generates code that does this, it is always safe to set. OutStreamer.EmitAssemblerFlag(MCAF_SubsectionsViaSymbols); } if (TT.isKnownWindowsMSVCEnvironment() && MMI->usesVAFloatArgument()) { StringRef SymbolName = (TT.getArch() == Triple::x86_64) ? "_fltused" : "__fltused"; MCSymbol *S = MMI->getContext().GetOrCreateSymbol(SymbolName); OutStreamer.EmitSymbolAttribute(S, MCSA_Global); } if (TT.isOSBinFormatCOFF()) { // Necessary for dllexport support std::vector<const MCSymbol*> DLLExportedFns, DLLExportedGlobals; for (const auto &Function : M) if (Function.hasDLLExportStorageClass() && !Function.isDeclaration()) DLLExportedFns.push_back(getSymbol(&Function)); for (const auto &Global : M.globals()) if (Global.hasDLLExportStorageClass() && !Global.isDeclaration()) DLLExportedGlobals.push_back(getSymbol(&Global)); for (const auto &Alias : M.aliases()) { if (!Alias.hasDLLExportStorageClass()) continue; if (Alias.getType()->getElementType()->isFunctionTy()) DLLExportedFns.push_back(getSymbol(&Alias)); else DLLExportedGlobals.push_back(getSymbol(&Alias)); } // Output linker support code for dllexported globals on windows. if (!DLLExportedGlobals.empty() || !DLLExportedFns.empty()) { const TargetLoweringObjectFileCOFF &TLOFCOFF = static_cast<const TargetLoweringObjectFileCOFF&>(getObjFileLowering()); OutStreamer.SwitchSection(TLOFCOFF.getDrectveSection()); for (auto & Symbol : DLLExportedGlobals) GenerateExportDirective(Symbol, /*IsData=*/true); for (auto & Symbol : DLLExportedFns) GenerateExportDirective(Symbol, /*IsData=*/false); } } if (TT.isOSBinFormatELF()) SM.serializeToStackMapSection(); } //===----------------------------------------------------------------------===// // Target Registry Stuff //===----------------------------------------------------------------------===// // Force static initialization. extern "C" void LLVMInitializeX86AsmPrinter() { RegisterAsmPrinter<X86AsmPrinter> X(TheX86_32Target); RegisterAsmPrinter<X86AsmPrinter> Y(TheX86_64Target); }