| //===-- AArch64AsmPrinter.cpp - AArch64 LLVM assembly writer --------------===// |
| // |
| // 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 the AArch64 assembly language. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "AArch64.h" |
| #include "AArch64MachineFunctionInfo.h" |
| #include "AArch64MCInstLower.h" |
| #include "AArch64RegisterInfo.h" |
| #include "AArch64Subtarget.h" |
| #include "InstPrinter/AArch64InstPrinter.h" |
| #include "llvm/ADT/SmallString.h" |
| #include "llvm/ADT/StringSwitch.h" |
| #include "llvm/ADT/Twine.h" |
| #include "llvm/CodeGen/AsmPrinter.h" |
| #include "llvm/CodeGen/MachineInstr.h" |
| #include "llvm/CodeGen/StackMaps.h" |
| #include "llvm/CodeGen/MachineModuleInfoImpls.h" |
| #include "llvm/CodeGen/TargetLoweringObjectFileImpl.h" |
| #include "llvm/IR/DataLayout.h" |
| #include "llvm/IR/DebugInfo.h" |
| #include "llvm/MC/MCAsmInfo.h" |
| #include "llvm/MC/MCContext.h" |
| #include "llvm/MC/MCInst.h" |
| #include "llvm/MC/MCInstBuilder.h" |
| #include "llvm/MC/MCLinkerOptimizationHint.h" |
| #include "llvm/MC/MCStreamer.h" |
| #include "llvm/Support/Debug.h" |
| #include "llvm/Support/TargetRegistry.h" |
| using namespace llvm; |
| |
| #define DEBUG_TYPE "asm-printer" |
| |
| namespace { |
| |
| class AArch64AsmPrinter : public AsmPrinter { |
| /// Subtarget - Keep a pointer to the AArch64Subtarget around so that we can |
| /// make the right decision when printing asm code for different targets. |
| const AArch64Subtarget *Subtarget; |
| |
| AArch64MCInstLower MCInstLowering; |
| StackMaps SM; |
| |
| public: |
| AArch64AsmPrinter(TargetMachine &TM, MCStreamer &Streamer) |
| : AsmPrinter(TM, Streamer), |
| Subtarget(&TM.getSubtarget<AArch64Subtarget>()), |
| MCInstLowering(OutContext, *Mang, *this), SM(*this), AArch64FI(nullptr), |
| LOHLabelCounter(0) {} |
| |
| const char *getPassName() const override { |
| return "AArch64 Assembly Printer"; |
| } |
| |
| /// \brief Wrapper for MCInstLowering.lowerOperand() for the |
| /// tblgen'erated pseudo lowering. |
| bool lowerOperand(const MachineOperand &MO, MCOperand &MCOp) const { |
| return MCInstLowering.lowerOperand(MO, MCOp); |
| } |
| |
| void LowerSTACKMAP(MCStreamer &OutStreamer, StackMaps &SM, |
| const MachineInstr &MI); |
| void LowerPATCHPOINT(MCStreamer &OutStreamer, StackMaps &SM, |
| const MachineInstr &MI); |
| /// \brief tblgen'erated driver function for lowering simple MI->MC |
| /// pseudo instructions. |
| bool emitPseudoExpansionLowering(MCStreamer &OutStreamer, |
| const MachineInstr *MI); |
| |
| void EmitInstruction(const MachineInstr *MI) override; |
| |
| void getAnalysisUsage(AnalysisUsage &AU) const override { |
| AsmPrinter::getAnalysisUsage(AU); |
| AU.setPreservesAll(); |
| } |
| |
| bool runOnMachineFunction(MachineFunction &F) override { |
| AArch64FI = F.getInfo<AArch64FunctionInfo>(); |
| return AsmPrinter::runOnMachineFunction(F); |
| } |
| |
| private: |
| MachineLocation getDebugValueLocation(const MachineInstr *MI) const; |
| void printOperand(const MachineInstr *MI, unsigned OpNum, raw_ostream &O); |
| bool printAsmMRegister(const MachineOperand &MO, char Mode, raw_ostream &O); |
| bool printAsmRegInClass(const MachineOperand &MO, |
| const TargetRegisterClass *RC, bool isVector, |
| raw_ostream &O); |
| |
| bool PrintAsmOperand(const MachineInstr *MI, unsigned OpNum, |
| unsigned AsmVariant, const char *ExtraCode, |
| raw_ostream &O) override; |
| bool PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNum, |
| unsigned AsmVariant, const char *ExtraCode, |
| raw_ostream &O) override; |
| |
| void PrintDebugValueComment(const MachineInstr *MI, raw_ostream &OS); |
| |
| void EmitFunctionBodyEnd() override; |
| |
| MCSymbol *GetCPISymbol(unsigned CPID) const override; |
| void EmitEndOfAsmFile(Module &M) override; |
| AArch64FunctionInfo *AArch64FI; |
| |
| /// \brief Emit the LOHs contained in AArch64FI. |
| void EmitLOHs(); |
| |
| typedef std::map<const MachineInstr *, MCSymbol *> MInstToMCSymbol; |
| MInstToMCSymbol LOHInstToLabel; |
| unsigned LOHLabelCounter; |
| }; |
| |
| } // end of anonymous namespace |
| |
| //===----------------------------------------------------------------------===// |
| |
| void AArch64AsmPrinter::EmitEndOfAsmFile(Module &M) { |
| if (Subtarget->isTargetMachO()) { |
| // 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); |
| SM.serializeToStackMapSection(); |
| } |
| |
| // Emit a .data.rel section containing any stubs that were created. |
| if (Subtarget->isTargetELF()) { |
| const TargetLoweringObjectFileELF &TLOFELF = |
| static_cast<const TargetLoweringObjectFileELF &>(getObjFileLowering()); |
| |
| MachineModuleInfoELF &MMIELF = MMI->getObjFileInfo<MachineModuleInfoELF>(); |
| |
| // Output stubs for external and common global variables. |
| MachineModuleInfoELF::SymbolListTy Stubs = MMIELF.GetGVStubList(); |
| if (!Stubs.empty()) { |
| OutStreamer.SwitchSection(TLOFELF.getDataRelSection()); |
| const DataLayout *TD = TM.getDataLayout(); |
| |
| for (unsigned i = 0, e = Stubs.size(); i != e; ++i) { |
| OutStreamer.EmitLabel(Stubs[i].first); |
| OutStreamer.EmitSymbolValue(Stubs[i].second.getPointer(), |
| TD->getPointerSize(0)); |
| } |
| Stubs.clear(); |
| } |
| } |
| |
| } |
| |
| MachineLocation |
| AArch64AsmPrinter::getDebugValueLocation(const MachineInstr *MI) const { |
| MachineLocation Location; |
| assert(MI->getNumOperands() == 4 && "Invalid no. of machine operands!"); |
| // Frame address. Currently handles register +- offset only. |
| if (MI->getOperand(0).isReg() && MI->getOperand(1).isImm()) |
| Location.set(MI->getOperand(0).getReg(), MI->getOperand(1).getImm()); |
| else { |
| DEBUG(dbgs() << "DBG_VALUE instruction ignored! " << *MI << "\n"); |
| } |
| return Location; |
| } |
| |
| void AArch64AsmPrinter::EmitLOHs() { |
| SmallVector<MCSymbol *, 3> MCArgs; |
| |
| for (const auto &D : AArch64FI->getLOHContainer()) { |
| for (const MachineInstr *MI : D.getArgs()) { |
| MInstToMCSymbol::iterator LabelIt = LOHInstToLabel.find(MI); |
| assert(LabelIt != LOHInstToLabel.end() && |
| "Label hasn't been inserted for LOH related instruction"); |
| MCArgs.push_back(LabelIt->second); |
| } |
| OutStreamer.EmitLOHDirective(D.getKind(), MCArgs); |
| MCArgs.clear(); |
| } |
| } |
| |
| void AArch64AsmPrinter::EmitFunctionBodyEnd() { |
| if (!AArch64FI->getLOHRelated().empty()) |
| EmitLOHs(); |
| } |
| |
| /// GetCPISymbol - Return the symbol for the specified constant pool entry. |
| MCSymbol *AArch64AsmPrinter::GetCPISymbol(unsigned CPID) const { |
| // Darwin uses a linker-private symbol name for constant-pools (to |
| // avoid addends on the relocation?), ELF has no such concept and |
| // uses a normal private symbol. |
| if (getDataLayout().getLinkerPrivateGlobalPrefix()[0]) |
| return OutContext.GetOrCreateSymbol( |
| Twine(getDataLayout().getLinkerPrivateGlobalPrefix()) + "CPI" + |
| Twine(getFunctionNumber()) + "_" + Twine(CPID)); |
| |
| return OutContext.GetOrCreateSymbol( |
| Twine(getDataLayout().getPrivateGlobalPrefix()) + "CPI" + |
| Twine(getFunctionNumber()) + "_" + Twine(CPID)); |
| } |
| |
| void AArch64AsmPrinter::printOperand(const MachineInstr *MI, unsigned OpNum, |
| raw_ostream &O) { |
| const MachineOperand &MO = MI->getOperand(OpNum); |
| switch (MO.getType()) { |
| default: |
| llvm_unreachable("<unknown operand type>"); |
| case MachineOperand::MO_Register: { |
| unsigned Reg = MO.getReg(); |
| assert(TargetRegisterInfo::isPhysicalRegister(Reg)); |
| assert(!MO.getSubReg() && "Subregs should be eliminated!"); |
| O << AArch64InstPrinter::getRegisterName(Reg); |
| break; |
| } |
| case MachineOperand::MO_Immediate: { |
| int64_t Imm = MO.getImm(); |
| O << '#' << Imm; |
| break; |
| } |
| } |
| } |
| |
| bool AArch64AsmPrinter::printAsmMRegister(const MachineOperand &MO, char Mode, |
| raw_ostream &O) { |
| unsigned Reg = MO.getReg(); |
| switch (Mode) { |
| default: |
| return true; // Unknown mode. |
| case 'w': |
| Reg = getWRegFromXReg(Reg); |
| break; |
| case 'x': |
| Reg = getXRegFromWReg(Reg); |
| break; |
| } |
| |
| O << AArch64InstPrinter::getRegisterName(Reg); |
| return false; |
| } |
| |
| // Prints the register in MO using class RC using the offset in the |
| // new register class. This should not be used for cross class |
| // printing. |
| bool AArch64AsmPrinter::printAsmRegInClass(const MachineOperand &MO, |
| const TargetRegisterClass *RC, |
| bool isVector, raw_ostream &O) { |
| assert(MO.isReg() && "Should only get here with a register!"); |
| const AArch64RegisterInfo *RI = |
| static_cast<const AArch64RegisterInfo *>(TM.getRegisterInfo()); |
| unsigned Reg = MO.getReg(); |
| unsigned RegToPrint = RC->getRegister(RI->getEncodingValue(Reg)); |
| assert(RI->regsOverlap(RegToPrint, Reg)); |
| O << AArch64InstPrinter::getRegisterName( |
| RegToPrint, isVector ? AArch64::vreg : AArch64::NoRegAltName); |
| return false; |
| } |
| |
| bool AArch64AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNum, |
| unsigned AsmVariant, |
| const char *ExtraCode, raw_ostream &O) { |
| const MachineOperand &MO = MI->getOperand(OpNum); |
| |
| // First try the generic code, which knows about modifiers like 'c' and 'n'. |
| if (!AsmPrinter::PrintAsmOperand(MI, OpNum, AsmVariant, ExtraCode, O)) |
| return false; |
| |
| // Does this asm operand have a single letter operand modifier? |
| if (ExtraCode && ExtraCode[0]) { |
| if (ExtraCode[1] != 0) |
| return true; // Unknown modifier. |
| |
| switch (ExtraCode[0]) { |
| default: |
| return true; // Unknown modifier. |
| case 'w': // Print W register |
| case 'x': // Print X register |
| if (MO.isReg()) |
| return printAsmMRegister(MO, ExtraCode[0], O); |
| if (MO.isImm() && MO.getImm() == 0) { |
| unsigned Reg = ExtraCode[0] == 'w' ? AArch64::WZR : AArch64::XZR; |
| O << AArch64InstPrinter::getRegisterName(Reg); |
| return false; |
| } |
| printOperand(MI, OpNum, O); |
| return false; |
| case 'b': // Print B register. |
| case 'h': // Print H register. |
| case 's': // Print S register. |
| case 'd': // Print D register. |
| case 'q': // Print Q register. |
| if (MO.isReg()) { |
| const TargetRegisterClass *RC; |
| switch (ExtraCode[0]) { |
| case 'b': |
| RC = &AArch64::FPR8RegClass; |
| break; |
| case 'h': |
| RC = &AArch64::FPR16RegClass; |
| break; |
| case 's': |
| RC = &AArch64::FPR32RegClass; |
| break; |
| case 'd': |
| RC = &AArch64::FPR64RegClass; |
| break; |
| case 'q': |
| RC = &AArch64::FPR128RegClass; |
| break; |
| default: |
| return true; |
| } |
| return printAsmRegInClass(MO, RC, false /* vector */, O); |
| } |
| printOperand(MI, OpNum, O); |
| return false; |
| } |
| } |
| |
| // According to ARM, we should emit x and v registers unless we have a |
| // modifier. |
| if (MO.isReg()) { |
| unsigned Reg = MO.getReg(); |
| |
| // If this is a w or x register, print an x register. |
| if (AArch64::GPR32allRegClass.contains(Reg) || |
| AArch64::GPR64allRegClass.contains(Reg)) |
| return printAsmMRegister(MO, 'x', O); |
| |
| // If this is a b, h, s, d, or q register, print it as a v register. |
| return printAsmRegInClass(MO, &AArch64::FPR128RegClass, true /* vector */, |
| O); |
| } |
| |
| printOperand(MI, OpNum, O); |
| return false; |
| } |
| |
| bool AArch64AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, |
| unsigned OpNum, |
| unsigned AsmVariant, |
| const char *ExtraCode, |
| raw_ostream &O) { |
| if (ExtraCode && ExtraCode[0]) |
| return true; // Unknown modifier. |
| |
| const MachineOperand &MO = MI->getOperand(OpNum); |
| assert(MO.isReg() && "unexpected inline asm memory operand"); |
| O << "[" << AArch64InstPrinter::getRegisterName(MO.getReg()) << "]"; |
| return false; |
| } |
| |
| void AArch64AsmPrinter::PrintDebugValueComment(const MachineInstr *MI, |
| raw_ostream &OS) { |
| unsigned NOps = MI->getNumOperands(); |
| assert(NOps == 4); |
| OS << '\t' << MAI->getCommentString() << "DEBUG_VALUE: "; |
| // cast away const; DIetc do not take const operands for some reason. |
| DIVariable V(const_cast<MDNode *>(MI->getOperand(NOps - 1).getMetadata())); |
| OS << V.getName(); |
| OS << " <- "; |
| // Frame address. Currently handles register +- offset only. |
| assert(MI->getOperand(0).isReg() && MI->getOperand(1).isImm()); |
| OS << '['; |
| printOperand(MI, 0, OS); |
| OS << '+'; |
| printOperand(MI, 1, OS); |
| OS << ']'; |
| OS << "+"; |
| printOperand(MI, NOps - 2, OS); |
| } |
| |
| void AArch64AsmPrinter::LowerSTACKMAP(MCStreamer &OutStreamer, StackMaps &SM, |
| const MachineInstr &MI) { |
| unsigned NumNOPBytes = MI.getOperand(1).getImm(); |
| |
| SM.recordStackMap(MI); |
| // Emit padding. |
| assert(NumNOPBytes % 4 == 0 && "Invalid number of NOP bytes requested!"); |
| for (unsigned i = 0; i < NumNOPBytes; i += 4) |
| EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::HINT).addImm(0)); |
| } |
| |
| // Lower a patchpoint of the form: |
| // [<def>], <id>, <numBytes>, <target>, <numArgs> |
| void AArch64AsmPrinter::LowerPATCHPOINT(MCStreamer &OutStreamer, StackMaps &SM, |
| const MachineInstr &MI) { |
| SM.recordPatchPoint(MI); |
| |
| PatchPointOpers Opers(&MI); |
| |
| int64_t CallTarget = Opers.getMetaOper(PatchPointOpers::TargetPos).getImm(); |
| unsigned EncodedBytes = 0; |
| if (CallTarget) { |
| assert((CallTarget & 0xFFFFFFFFFFFF) == CallTarget && |
| "High 16 bits of call target should be zero."); |
| unsigned ScratchReg = MI.getOperand(Opers.getNextScratchIdx()).getReg(); |
| EncodedBytes = 16; |
| // Materialize the jump address: |
| EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::MOVZWi) |
| .addReg(ScratchReg) |
| .addImm((CallTarget >> 32) & 0xFFFF) |
| .addImm(32)); |
| EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::MOVKWi) |
| .addReg(ScratchReg) |
| .addReg(ScratchReg) |
| .addImm((CallTarget >> 16) & 0xFFFF) |
| .addImm(16)); |
| EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::MOVKWi) |
| .addReg(ScratchReg) |
| .addReg(ScratchReg) |
| .addImm(CallTarget & 0xFFFF) |
| .addImm(0)); |
| EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::BLR).addReg(ScratchReg)); |
| } |
| // Emit padding. |
| unsigned NumBytes = Opers.getMetaOper(PatchPointOpers::NBytesPos).getImm(); |
| assert(NumBytes >= EncodedBytes && |
| "Patchpoint can't request size less than the length of a call."); |
| assert((NumBytes - EncodedBytes) % 4 == 0 && |
| "Invalid number of NOP bytes requested!"); |
| for (unsigned i = EncodedBytes; i < NumBytes; i += 4) |
| EmitToStreamer(OutStreamer, MCInstBuilder(AArch64::HINT).addImm(0)); |
| } |
| |
| // Simple pseudo-instructions have their lowering (with expansion to real |
| // instructions) auto-generated. |
| #include "AArch64GenMCPseudoLowering.inc" |
| |
| void AArch64AsmPrinter::EmitInstruction(const MachineInstr *MI) { |
| // Do any auto-generated pseudo lowerings. |
| if (emitPseudoExpansionLowering(OutStreamer, MI)) |
| return; |
| |
| if (AArch64FI->getLOHRelated().count(MI)) { |
| // Generate a label for LOH related instruction |
| MCSymbol *LOHLabel = GetTempSymbol("loh", LOHLabelCounter++); |
| // Associate the instruction with the label |
| LOHInstToLabel[MI] = LOHLabel; |
| OutStreamer.EmitLabel(LOHLabel); |
| } |
| |
| // Do any manual lowerings. |
| switch (MI->getOpcode()) { |
| default: |
| break; |
| case AArch64::DBG_VALUE: { |
| if (isVerbose() && OutStreamer.hasRawTextSupport()) { |
| SmallString<128> TmpStr; |
| raw_svector_ostream OS(TmpStr); |
| PrintDebugValueComment(MI, OS); |
| OutStreamer.EmitRawText(StringRef(OS.str())); |
| } |
| return; |
| } |
| |
| // Tail calls use pseudo instructions so they have the proper code-gen |
| // attributes (isCall, isReturn, etc.). We lower them to the real |
| // instruction here. |
| case AArch64::TCRETURNri: { |
| MCInst TmpInst; |
| TmpInst.setOpcode(AArch64::BR); |
| TmpInst.addOperand(MCOperand::CreateReg(MI->getOperand(0).getReg())); |
| EmitToStreamer(OutStreamer, TmpInst); |
| return; |
| } |
| case AArch64::TCRETURNdi: { |
| MCOperand Dest; |
| MCInstLowering.lowerOperand(MI->getOperand(0), Dest); |
| MCInst TmpInst; |
| TmpInst.setOpcode(AArch64::B); |
| TmpInst.addOperand(Dest); |
| EmitToStreamer(OutStreamer, TmpInst); |
| return; |
| } |
| case AArch64::TLSDESC_BLR: { |
| MCOperand Callee, Sym; |
| MCInstLowering.lowerOperand(MI->getOperand(0), Callee); |
| MCInstLowering.lowerOperand(MI->getOperand(1), Sym); |
| |
| // First emit a relocation-annotation. This expands to no code, but requests |
| // the following instruction gets an R_AARCH64_TLSDESC_CALL. |
| MCInst TLSDescCall; |
| TLSDescCall.setOpcode(AArch64::TLSDESCCALL); |
| TLSDescCall.addOperand(Sym); |
| EmitToStreamer(OutStreamer, TLSDescCall); |
| |
| // Other than that it's just a normal indirect call to the function loaded |
| // from the descriptor. |
| MCInst BLR; |
| BLR.setOpcode(AArch64::BLR); |
| BLR.addOperand(Callee); |
| EmitToStreamer(OutStreamer, BLR); |
| |
| return; |
| } |
| |
| case TargetOpcode::STACKMAP: |
| return LowerSTACKMAP(OutStreamer, SM, *MI); |
| |
| case TargetOpcode::PATCHPOINT: |
| return LowerPATCHPOINT(OutStreamer, SM, *MI); |
| } |
| |
| // Finally, do the automated lowerings for everything else. |
| MCInst TmpInst; |
| MCInstLowering.Lower(MI, TmpInst); |
| EmitToStreamer(OutStreamer, TmpInst); |
| } |
| |
| // Force static initialization. |
| extern "C" void LLVMInitializeAArch64AsmPrinter() { |
| RegisterAsmPrinter<AArch64AsmPrinter> X(TheAArch64leTarget); |
| RegisterAsmPrinter<AArch64AsmPrinter> Y(TheAArch64beTarget); |
| |
| RegisterAsmPrinter<AArch64AsmPrinter> Z(TheARM64leTarget); |
| RegisterAsmPrinter<AArch64AsmPrinter> W(TheARM64beTarget); |
| } |
