AsmPrinter.cpp revision 205407
16059Samurai//===-- AsmPrinter.cpp - Common AsmPrinter code ---------------------------===// 26059Samurai// 36059Samurai// The LLVM Compiler Infrastructure 46059Samurai// 56059Samurai// This file is distributed under the University of Illinois Open Source 66059Samurai// License. See LICENSE.TXT for details. 76059Samurai// 86059Samurai//===----------------------------------------------------------------------===// 96059Samurai// 106059Samurai// This file implements the AsmPrinter class. 116059Samurai// 126059Samurai//===----------------------------------------------------------------------===// 136059Samurai 146059Samurai#define DEBUG_TYPE "asm-printer" 156059Samurai#include "llvm/CodeGen/AsmPrinter.h" 166059Samurai#include "llvm/Assembly/Writer.h" 176059Samurai#include "llvm/DerivedTypes.h" 186059Samurai#include "llvm/Constants.h" 196059Samurai#include "llvm/Module.h" 206764Samurai#include "llvm/CodeGen/DwarfWriter.h" 216735Samurai#include "llvm/CodeGen/GCMetadataPrinter.h" 226059Samurai#include "llvm/CodeGen/MachineConstantPool.h" 236059Samurai#include "llvm/CodeGen/MachineFrameInfo.h" 246059Samurai#include "llvm/CodeGen/MachineFunction.h" 256059Samurai#include "llvm/CodeGen/MachineJumpTableInfo.h" 266059Samurai#include "llvm/CodeGen/MachineLoopInfo.h" 276059Samurai#include "llvm/CodeGen/MachineModuleInfo.h" 286059Samurai#include "llvm/Analysis/ConstantFolding.h" 296059Samurai#include "llvm/Analysis/DebugInfo.h" 306059Samurai#include "llvm/MC/MCContext.h" 316059Samurai#include "llvm/MC/MCExpr.h" 326059Samurai#include "llvm/MC/MCInst.h" 336059Samurai#include "llvm/MC/MCSection.h" 346059Samurai#include "llvm/MC/MCStreamer.h" 356059Samurai#include "llvm/MC/MCSymbol.h" 366059Samurai#include "llvm/MC/MCAsmInfo.h" 376059Samurai#include "llvm/Target/Mangler.h" 386059Samurai#include "llvm/Target/TargetData.h" 396059Samurai#include "llvm/Target/TargetInstrInfo.h" 406059Samurai#include "llvm/Target/TargetLowering.h" 416059Samurai#include "llvm/Target/TargetLoweringObjectFile.h" 426735Samurai#include "llvm/Target/TargetOptions.h" 436059Samurai#include "llvm/Target/TargetRegisterInfo.h" 446764Samurai#include "llvm/ADT/SmallPtrSet.h" 456764Samurai#include "llvm/ADT/SmallString.h" 466764Samurai#include "llvm/ADT/Statistic.h" 476735Samurai#include "llvm/Support/CommandLine.h" 486735Samurai#include "llvm/Support/Debug.h" 496735Samurai#include "llvm/Support/ErrorHandling.h" 506735Samurai#include "llvm/Support/Format.h" 516735Samurai#include "llvm/Support/FormattedStream.h" 526735Samurai#include <cerrno> 536059Samuraiusing namespace llvm; 546059Samurai 556059SamuraiSTATISTIC(EmittedInsts, "Number of machine instrs printed"); 566059Samurai 576059Samuraichar AsmPrinter::ID = 0; 586059Samurai 596059SamuraiAsmPrinter::AsmPrinter(formatted_raw_ostream &o, TargetMachine &tm, 606059Samurai MCStreamer &Streamer) 616059Samurai : MachineFunctionPass(&ID), O(o), 626059Samurai TM(tm), MAI(tm.getMCAsmInfo()), TRI(tm.getRegisterInfo()), 636059Samurai OutContext(Streamer.getContext()), 646059Samurai OutStreamer(Streamer), 656059Samurai LastMI(0), LastFn(0), Counter(~0U), SetCounter(0), PrevDLT(NULL) { 666059Samurai DW = 0; MMI = 0; 676059Samurai VerboseAsm = Streamer.isVerboseAsm(); 686059Samurai} 696059Samurai 706059SamuraiAsmPrinter::~AsmPrinter() { 716059Samurai for (gcp_iterator I = GCMetadataPrinters.begin(), 726059Samurai E = GCMetadataPrinters.end(); I != E; ++I) 736059Samurai delete I->second; 746059Samurai 756059Samurai delete &OutStreamer; 766059Samurai} 776059Samurai 786059Samurai/// getFunctionNumber - Return a unique ID for the current function. 796059Samurai/// 806059Samuraiunsigned AsmPrinter::getFunctionNumber() const { 816059Samurai return MF->getFunctionNumber(); 826059Samurai} 836059Samurai 846059SamuraiTargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const { 856059Samurai return TM.getTargetLowering()->getObjFileLowering(); 866735Samurai} 876059Samurai 886059Samurai/// getCurrentSection() - Return the current section we are emitting to. 896059Samuraiconst MCSection *AsmPrinter::getCurrentSection() const { 906059Samurai return OutStreamer.getCurrentSection(); 916059Samurai} 926059Samurai 936059Samurai 946059Samuraivoid AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const { 956059Samurai AU.setPreservesAll(); 966059Samurai MachineFunctionPass::getAnalysisUsage(AU); 976059Samurai AU.addRequired<MachineModuleInfo>(); 986059Samurai AU.addRequired<GCModuleInfo>(); 996059Samurai if (VerboseAsm) 1006059Samurai AU.addRequired<MachineLoopInfo>(); 1016735Samurai} 1026059Samurai 1036059Samuraibool AsmPrinter::doInitialization(Module &M) { 1046059Samurai MMI = getAnalysisIfAvailable<MachineModuleInfo>(); 1056735Samurai MMI->AnalyzeModule(M); 1066059Samurai 1076059Samurai // Initialize TargetLoweringObjectFile. 1086059Samurai const_cast<TargetLoweringObjectFile&>(getObjFileLowering()) 1096059Samurai .Initialize(OutContext, TM); 1106059Samurai 1116059Samurai Mang = new Mangler(OutContext, *TM.getTargetData()); 1126059Samurai 1136059Samurai // Allow the target to emit any magic that it wants at the start of the file. 1146059Samurai EmitStartOfAsmFile(M); 1156059Samurai 1166059Samurai // Very minimal debug info. It is ignored if we emit actual debug info. If we 1176059Samurai // don't, this at least helps the user find where a global came from. 1186059Samurai if (MAI->hasSingleParameterDotFile()) { 1196059Samurai // .file "foo.c" 1206059Samurai OutStreamer.EmitFileDirective(M.getModuleIdentifier()); 1216735Samurai } 1226059Samurai 1236059Samurai GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>(); 1246059Samurai assert(MI && "AsmPrinter didn't require GCModuleInfo?"); 1256059Samurai for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I) 1266059Samurai if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I)) 1276059Samurai MP->beginAssembly(O, *this, *MAI); 1286059Samurai 1296059Samurai if (!M.getModuleInlineAsm().empty()) 1306059Samurai O << MAI->getCommentString() << " Start of file scope inline assembly\n" 1316059Samurai << M.getModuleInlineAsm() 1326059Samurai << '\n' << MAI->getCommentString() 1336059Samurai << " End of file scope inline assembly\n"; 1346059Samurai 1356735Samurai DW = getAnalysisIfAvailable<DwarfWriter>(); 1366059Samurai if (DW) 1376059Samurai DW->BeginModule(&M, MMI, O, this, MAI); 1386059Samurai 1396735Samurai return false; 1406735Samurai} 1416059Samurai 1426059Samuraivoid AsmPrinter::EmitLinkage(unsigned Linkage, MCSymbol *GVSym) const { 1436059Samurai switch ((GlobalValue::LinkageTypes)Linkage) { 1446059Samurai case GlobalValue::CommonLinkage: 1456059Samurai case GlobalValue::LinkOnceAnyLinkage: 1466059Samurai case GlobalValue::LinkOnceODRLinkage: 1476059Samurai case GlobalValue::WeakAnyLinkage: 1486059Samurai case GlobalValue::WeakODRLinkage: 1496059Samurai case GlobalValue::LinkerPrivateLinkage: 1506735Samurai if (MAI->getWeakDefDirective() != 0) { 1516735Samurai // .globl _foo 1526735Samurai OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global); 1536735Samurai // .weak_definition _foo 1546735Samurai OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition); 1556735Samurai } else if (const char *LinkOnce = MAI->getLinkOnceDirective()) { 1566059Samurai // .globl _foo 1576059Samurai OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global); 1586059Samurai // FIXME: linkonce should be a section attribute, handled by COFF Section 1596059Samurai // assignment. 1606059Samurai // http://sourceware.org/binutils/docs-2.20/as/Linkonce.html#Linkonce 1616059Samurai // .linkonce discard 1626059Samurai // FIXME: It would be nice to use .linkonce samesize for non-common 1636059Samurai // globals. 1646059Samurai O << LinkOnce; 1656059Samurai } else { 1666059Samurai // .weak _foo 1676059Samurai OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak); 1686059Samurai } 1696059Samurai break; 1706059Samurai case GlobalValue::DLLExportLinkage: 1716059Samurai case GlobalValue::AppendingLinkage: 1726059Samurai // FIXME: appending linkage variables should go into a section of 1736059Samurai // their name or something. For now, just emit them as external. 1746059Samurai case GlobalValue::ExternalLinkage: 1756059Samurai // If external or appending, declare as a global symbol. 1766059Samurai // .globl _foo 1776059Samurai OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global); 1786059Samurai break; 1796059Samurai case GlobalValue::PrivateLinkage: 1806059Samurai case GlobalValue::InternalLinkage: 1816059Samurai break; 1826059Samurai default: 1836059Samurai llvm_unreachable("Unknown linkage type!"); 1846059Samurai } 1856059Samurai} 1866059Samurai 1876059Samurai 1886059Samurai/// EmitGlobalVariable - Emit the specified global variable to the .s file. 1896059Samuraivoid AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) { 1906059Samurai if (!GV->hasInitializer()) // External globals require no code. 1916059Samurai return; 1926059Samurai 1936059Samurai // Check to see if this is a special global used by LLVM, if so, emit it. 1946059Samurai if (EmitSpecialLLVMGlobal(GV)) 1956059Samurai return; 1966059Samurai 1976059Samurai MCSymbol *GVSym = Mang->getSymbol(GV); 1986059Samurai EmitVisibility(GVSym, GV->getVisibility()); 1996059Samurai 2006059Samurai if (MAI->hasDotTypeDotSizeDirective()) 2016059Samurai OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject); 2026059Samurai 2036059Samurai SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM); 2046059Samurai 2056059Samurai const TargetData *TD = TM.getTargetData(); 2066059Samurai unsigned Size = TD->getTypeAllocSize(GV->getType()->getElementType()); 2076059Samurai unsigned AlignLog = TD->getPreferredAlignmentLog(GV); 2086059Samurai 2096059Samurai // Handle common and BSS local symbols (.lcomm). 2106059Samurai if (GVKind.isCommon() || GVKind.isBSSLocal()) { 2116059Samurai if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it. 2126059Samurai 2136059Samurai if (VerboseAsm) { 2146059Samurai WriteAsOperand(OutStreamer.GetCommentOS(), GV, 2156059Samurai /*PrintType=*/false, GV->getParent()); 2166059Samurai OutStreamer.GetCommentOS() << '\n'; 2176059Samurai } 2186059Samurai 2196059Samurai // Handle common symbols. 2206059Samurai if (GVKind.isCommon()) { 2216059Samurai // .comm _foo, 42, 4 2226059Samurai OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog); 2236059Samurai return; 2246059Samurai } 2256059Samurai 2266059Samurai // Handle local BSS symbols. 2276059Samurai if (MAI->hasMachoZeroFillDirective()) { 2286059Samurai const MCSection *TheSection = 2296059Samurai getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM); 2306059Samurai // .zerofill __DATA, __bss, _foo, 400, 5 2316059Samurai OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog); 2326059Samurai return; 2336059Samurai } 2346059Samurai 2356059Samurai if (MAI->hasLCOMMDirective()) { 2366059Samurai // .lcomm _foo, 42 2376059Samurai OutStreamer.EmitLocalCommonSymbol(GVSym, Size); 2386059Samurai return; 2396059Samurai } 2406059Samurai 2416059Samurai // .local _foo 2426059Samurai OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local); 2436059Samurai // .comm _foo, 42, 4 2446059Samurai OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog); 2456059Samurai return; 2466735Samurai } 2476735Samurai 2486764Samurai const MCSection *TheSection = 2496764Samurai getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM); 2506764Samurai 2516764Samurai // Handle the zerofill directive on darwin, which is a special form of BSS 2526764Samurai // emission. 2536735Samurai if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) { 2546735Samurai // .globl _foo 2556735Samurai OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global); 2566735Samurai // .zerofill __DATA, __common, _foo, 400, 5 2576735Samurai OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog); 2586735Samurai return; 2596059Samurai } 2606059Samurai 2616059Samurai OutStreamer.SwitchSection(TheSection); 2626059Samurai 2636059Samurai EmitLinkage(GV->getLinkage(), GVSym); 2646059Samurai EmitAlignment(AlignLog, GV); 2656059Samurai 2666059Samurai if (VerboseAsm) { 2676059Samurai WriteAsOperand(OutStreamer.GetCommentOS(), GV, 2686059Samurai /*PrintType=*/false, GV->getParent()); 2696059Samurai OutStreamer.GetCommentOS() << '\n'; 2706059Samurai } 2716059Samurai OutStreamer.EmitLabel(GVSym); 2726059Samurai 2736059Samurai EmitGlobalConstant(GV->getInitializer()); 2746059Samurai 2756059Samurai if (MAI->hasDotTypeDotSizeDirective()) 2766059Samurai // .size foo, 42 2776735Samurai OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext)); 2786059Samurai 2796059Samurai OutStreamer.AddBlankLine(); 2806059Samurai} 2816059Samurai 2826735Samurai/// EmitFunctionHeader - This method emits the header for the current 2836059Samurai/// function. 2846735Samuraivoid AsmPrinter::EmitFunctionHeader() { 2856735Samurai // Print out constants referenced by the function 2866735Samurai EmitConstantPool(); 2876735Samurai 2886735Samurai // Print the 'header' of function. 2896735Samurai const Function *F = MF->getFunction(); 2906735Samurai 2916059Samurai OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM)); 2926059Samurai EmitVisibility(CurrentFnSym, F->getVisibility()); 2936059Samurai 2946059Samurai EmitLinkage(F->getLinkage(), CurrentFnSym); 2956059Samurai EmitAlignment(MF->getAlignment(), F); 2966059Samurai 2976059Samurai if (MAI->hasDotTypeDotSizeDirective()) 2986059Samurai OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction); 2996059Samurai 3006059Samurai if (VerboseAsm) { 3016059Samurai WriteAsOperand(OutStreamer.GetCommentOS(), F, 3026059Samurai /*PrintType=*/false, F->getParent()); 3036059Samurai OutStreamer.GetCommentOS() << '\n'; 3046059Samurai } 3056059Samurai 3066059Samurai // Emit the CurrentFnSym. This is a virtual function to allow targets to 3076059Samurai // do their wild and crazy things as required. 3086059Samurai EmitFunctionEntryLabel(); 3096059Samurai 3106059Samurai // If the function had address-taken blocks that got deleted, then we have 3116059Samurai // references to the dangling symbols. Emit them at the start of the function 3126059Samurai // so that we don't get references to undefined symbols. 3136059Samurai std::vector<MCSymbol*> DeadBlockSyms; 3146059Samurai MMI->takeDeletedSymbolsForFunction(F, DeadBlockSyms); 3156059Samurai for (unsigned i = 0, e = DeadBlockSyms.size(); i != e; ++i) { 3166059Samurai OutStreamer.AddComment("Address taken block that was later removed"); 3176059Samurai OutStreamer.EmitLabel(DeadBlockSyms[i]); 3186059Samurai } 3196059Samurai 3206059Samurai // Add some workaround for linkonce linkage on Cygwin\MinGW. 3216059Samurai if (MAI->getLinkOnceDirective() != 0 && 3226059Samurai (F->hasLinkOnceLinkage() || F->hasWeakLinkage())) 3236059Samurai // FIXME: What is this? 3246059Samurai O << "Lllvm$workaround$fake$stub$" << *CurrentFnSym << ":\n"; 3256059Samurai 3266059Samurai // Emit pre-function debug and/or EH information. 3276059Samurai if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling()) 3286059Samurai DW->BeginFunction(MF); 3296059Samurai} 3306059Samurai 3316059Samurai/// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the 3326059Samurai/// function. This can be overridden by targets as required to do custom stuff. 3336059Samuraivoid AsmPrinter::EmitFunctionEntryLabel() { 3346059Samurai OutStreamer.EmitLabel(CurrentFnSym); 3356059Samurai} 3366059Samurai 3376059Samurai 3386059Samurai/// EmitComments - Pretty-print comments for instructions. 3396735Samuraistatic void EmitComments(const MachineInstr &MI, raw_ostream &CommentOS) { 3406059Samurai const MachineFunction *MF = MI.getParent()->getParent(); 3416059Samurai const TargetMachine &TM = MF->getTarget(); 3426059Samurai 3436059Samurai if (!MI.getDebugLoc().isUnknown()) { 3446059Samurai DILocation DLT = MF->getDILocation(MI.getDebugLoc()); 3456059Samurai 3466059Samurai // Print source line info. 3476059Samurai DIScope Scope = DLT.getScope(); 3486059Samurai // Omit the directory, because it's likely to be long and uninteresting. 3496059Samurai if (Scope.Verify()) 3506059Samurai CommentOS << Scope.getFilename(); 3516059Samurai else 3526059Samurai CommentOS << "<unknown>"; 3536059Samurai CommentOS << ':' << DLT.getLineNumber(); 3546059Samurai if (DLT.getColumnNumber() != 0) 3556059Samurai CommentOS << ':' << DLT.getColumnNumber(); 3566059Samurai CommentOS << '\n'; 3576059Samurai } 3586059Samurai 3596059Samurai // Check for spills and reloads 3606059Samurai int FI; 3616059Samurai 3626059Samurai const MachineFrameInfo *FrameInfo = MF->getFrameInfo(); 3636059Samurai 3646059Samurai // We assume a single instruction only has a spill or reload, not 3656059Samurai // both. 3666059Samurai const MachineMemOperand *MMO; 3676059Samurai if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) { 3686059Samurai if (FrameInfo->isSpillSlotObjectIndex(FI)) { 3696059Samurai MMO = *MI.memoperands_begin(); 3706059Samurai CommentOS << MMO->getSize() << "-byte Reload\n"; 3716059Samurai } 3726059Samurai } else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) { 3736059Samurai if (FrameInfo->isSpillSlotObjectIndex(FI)) 3746059Samurai CommentOS << MMO->getSize() << "-byte Folded Reload\n"; 3756059Samurai } else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) { 3766059Samurai if (FrameInfo->isSpillSlotObjectIndex(FI)) { 3776059Samurai MMO = *MI.memoperands_begin(); 3786059Samurai CommentOS << MMO->getSize() << "-byte Spill\n"; 3796059Samurai } 3806059Samurai } else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) { 3816059Samurai if (FrameInfo->isSpillSlotObjectIndex(FI)) 3826059Samurai CommentOS << MMO->getSize() << "-byte Folded Spill\n"; 3836059Samurai } 3846059Samurai 3856059Samurai // Check for spill-induced copies 3866059Samurai unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx; 3876059Samurai if (TM.getInstrInfo()->isMoveInstr(MI, SrcReg, DstReg, 3886059Samurai SrcSubIdx, DstSubIdx)) { 3896059Samurai if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse)) 3906059Samurai CommentOS << " Reload Reuse\n"; 3916059Samurai } 3926059Samurai} 3936059Samurai 3946059Samurai 3956059Samurai 3966059Samurai/// EmitFunctionBody - This method emits the body and trailer for a 3976059Samurai/// function. 3986059Samuraivoid AsmPrinter::EmitFunctionBody() { 3996059Samurai // Emit target-specific gunk before the function body. 4006059Samurai EmitFunctionBodyStart(); 4016059Samurai 4026059Samurai // Print out code for the function. 4036059Samurai bool HasAnyRealCode = false; 4046059Samurai for (MachineFunction::const_iterator I = MF->begin(), E = MF->end(); 4056059Samurai I != E; ++I) { 4066059Samurai // Print a label for the basic block. 4076059Samurai EmitBasicBlockStart(I); 4086059Samurai for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end(); 4096059Samurai II != IE; ++II) { 4106059Samurai // Print the assembly for the instruction. 4116059Samurai if (!II->isLabel()) 4126735Samurai HasAnyRealCode = true; 4136059Samurai 4146735Samurai ++EmittedInsts; 4156059Samurai 4166059Samurai // FIXME: Clean up processDebugLoc. 4176059Samurai processDebugLoc(II, true); 4186059Samurai 4196059Samurai if (VerboseAsm) 4206059Samurai EmitComments(*II, OutStreamer.GetCommentOS()); 4216059Samurai 4226059Samurai switch (II->getOpcode()) { 4236059Samurai case TargetOpcode::DBG_LABEL: 4246059Samurai case TargetOpcode::EH_LABEL: 4256059Samurai case TargetOpcode::GC_LABEL: 4266059Samurai printLabelInst(II); 4276059Samurai break; 4286059Samurai case TargetOpcode::INLINEASM: 4296059Samurai printInlineAsm(II); 4306059Samurai break; 4316059Samurai case TargetOpcode::IMPLICIT_DEF: 4326059Samurai printImplicitDef(II); 4336059Samurai break; 4346059Samurai case TargetOpcode::KILL: 4356059Samurai printKill(II); 4366059Samurai break; 4376059Samurai default: 4386059Samurai EmitInstruction(II); 4396059Samurai break; 4406059Samurai } 4416059Samurai 4426059Samurai // FIXME: Clean up processDebugLoc. 4436059Samurai processDebugLoc(II, false); 4446059Samurai } 4456059Samurai } 4466059Samurai 4476059Samurai // If the function is empty and the object file uses .subsections_via_symbols, 4486059Samurai // then we need to emit *something* to the function body to prevent the 4496059Samurai // labels from collapsing together. Just emit a 0 byte. 4506059Samurai if (MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode) 4516059Samurai OutStreamer.EmitIntValue(0, 1, 0/*addrspace*/); 4526059Samurai 4536059Samurai // Emit target-specific gunk after the function body. 4546059Samurai EmitFunctionBodyEnd(); 4556059Samurai 4566059Samurai if (MAI->hasDotTypeDotSizeDirective()) 4576059Samurai O << "\t.size\t" << *CurrentFnSym << ", .-" << *CurrentFnSym << '\n'; 4586059Samurai 4596059Samurai // Emit post-function debug information. 4606059Samurai if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling()) 4616059Samurai DW->EndFunction(MF); 4626059Samurai 4636059Samurai // Print out jump tables referenced by the function. 4646059Samurai EmitJumpTableInfo(); 4656059Samurai 4666059Samurai OutStreamer.AddBlankLine(); 4676059Samurai} 4686059Samurai 4696059Samurai 4706059Samuraibool AsmPrinter::doFinalization(Module &M) { 4716059Samurai // Emit global variables. 4726059Samurai for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); 4736059Samurai I != E; ++I) 4746059Samurai EmitGlobalVariable(I); 4756059Samurai 4766059Samurai // Emit final debug information. 4776059Samurai if (MAI->doesSupportDebugInformation() || MAI->doesSupportExceptionHandling()) 4786059Samurai DW->EndModule(); 4796059Samurai 4806059Samurai // If the target wants to know about weak references, print them all. 4816059Samurai if (MAI->getWeakRefDirective()) { 4826059Samurai // FIXME: This is not lazy, it would be nice to only print weak references 4836059Samurai // to stuff that is actually used. Note that doing so would require targets 4846059Samurai // to notice uses in operands (due to constant exprs etc). This should 4856059Samurai // happen with the MC stuff eventually. 4866059Samurai 4876059Samurai // Print out module-level global variables here. 4886059Samurai for (Module::const_global_iterator I = M.global_begin(), E = M.global_end(); 4896059Samurai I != E; ++I) { 4906059Samurai if (!I->hasExternalWeakLinkage()) continue; 4916059Samurai OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference); 4926059Samurai } 4936059Samurai 4946059Samurai for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) { 4956059Samurai if (!I->hasExternalWeakLinkage()) continue; 4966735Samurai OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference); 4976735Samurai } 4986735Samurai } 4996735Samurai 5006735Samurai if (MAI->hasSetDirective()) { 5016059Samurai OutStreamer.AddBlankLine(); 5026059Samurai for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end(); 5036059Samurai I != E; ++I) { 5046059Samurai MCSymbol *Name = Mang->getSymbol(I); 5056059Samurai 5066059Samurai const GlobalValue *GV = cast<GlobalValue>(I->getAliasedGlobal()); 5076059Samurai MCSymbol *Target = Mang->getSymbol(GV); 5086059Samurai 5096735Samurai if (I->hasExternalLinkage() || !MAI->getWeakRefDirective()) 5106059Samurai OutStreamer.EmitSymbolAttribute(Name, MCSA_Global); 5116059Samurai else if (I->hasWeakLinkage()) 5126059Samurai OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference); 5136059Samurai else 5146735Samurai assert(I->hasLocalLinkage() && "Invalid alias linkage"); 5156735Samurai 5166735Samurai EmitVisibility(Name, I->getVisibility()); 5176735Samurai 5186059Samurai // Emit the directives as assignments aka .set: 5196059Samurai OutStreamer.EmitAssignment(Name, 5206059Samurai MCSymbolRefExpr::Create(Target, OutContext)); 5216059Samurai } 5226059Samurai } 5236059Samurai 5246059Samurai GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>(); 5256059Samurai assert(MI && "AsmPrinter didn't require GCModuleInfo?"); 5266059Samurai for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; ) 5276059Samurai if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I)) 5286059Samurai MP->finishAssembly(O, *this, *MAI); 5296059Samurai 5306059Samurai // If we don't have any trampolines, then we don't require stack memory 5316059Samurai // to be executable. Some targets have a directive to declare this. 5326059Samurai Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline"); 5336059Samurai if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty()) 5346059Samurai if (MCSection *S = MAI->getNonexecutableStackSection(OutContext)) 5356059Samurai OutStreamer.SwitchSection(S); 5366059Samurai 5376059Samurai // Allow the target to emit any magic that it wants at the end of the file, 5386059Samurai // after everything else has gone out. 5396059Samurai EmitEndOfAsmFile(M); 5406059Samurai 5416059Samurai delete Mang; Mang = 0; 5426059Samurai DW = 0; MMI = 0; 5436059Samurai 5446059Samurai OutStreamer.Finish(); 5456059Samurai return false; 5466059Samurai} 5476059Samurai 5486059Samuraivoid AsmPrinter::SetupMachineFunction(MachineFunction &MF) { 5496059Samurai this->MF = &MF; 5506059Samurai // Get the function symbol. 5516059Samurai CurrentFnSym = Mang->getSymbol(MF.getFunction()); 5526059Samurai 5536059Samurai if (VerboseAsm) 5546735Samurai LI = &getAnalysis<MachineLoopInfo>(); 5556059Samurai} 5566059Samurai 5576059Samurainamespace { 5586059Samurai // SectionCPs - Keep track the alignment, constpool entries per Section. 5596059Samurai struct SectionCPs { 5606059Samurai const MCSection *S; 5616059Samurai unsigned Alignment; 5626059Samurai SmallVector<unsigned, 4> CPEs; 5636059Samurai SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {} 5646059Samurai }; 5656059Samurai} 5666059Samurai 5676059Samurai/// EmitConstantPool - Print to the current output stream assembly 5686735Samurai/// representations of the constants in the constant pool MCP. This is 5696735Samurai/// used to print out constants which have been "spilled to memory" by 5706735Samurai/// the code generator. 5716735Samurai/// 5726735Samuraivoid AsmPrinter::EmitConstantPool() { 5736735Samurai const MachineConstantPool *MCP = MF->getConstantPool(); 5746059Samurai const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants(); 5756735Samurai if (CP.empty()) return; 5766059Samurai 5776059Samurai // Calculate sections for constant pool entries. We collect entries to go into 5786059Samurai // the same section together to reduce amount of section switch statements. 5796059Samurai SmallVector<SectionCPs, 4> CPSections; 5806059Samurai for (unsigned i = 0, e = CP.size(); i != e; ++i) { 5816059Samurai const MachineConstantPoolEntry &CPE = CP[i]; 5826059Samurai unsigned Align = CPE.getAlignment(); 5836059Samurai 5846059Samurai SectionKind Kind; 5856059Samurai switch (CPE.getRelocationInfo()) { 5866059Samurai default: llvm_unreachable("Unknown section kind"); 5876059Samurai case 2: Kind = SectionKind::getReadOnlyWithRel(); break; 5886059Samurai case 1: 5896059Samurai Kind = SectionKind::getReadOnlyWithRelLocal(); 5906735Samurai break; 5916059Samurai case 0: 5926059Samurai switch (TM.getTargetData()->getTypeAllocSize(CPE.getType())) { 5936735Samurai case 4: Kind = SectionKind::getMergeableConst4(); break; 5946059Samurai case 8: Kind = SectionKind::getMergeableConst8(); break; 5956059Samurai case 16: Kind = SectionKind::getMergeableConst16();break; 5966059Samurai default: Kind = SectionKind::getMergeableConst(); break; 5976059Samurai } 5986735Samurai } 5996735Samurai 6006735Samurai const MCSection *S = getObjFileLowering().getSectionForConstant(Kind); 6016059Samurai 6026059Samurai // The number of sections are small, just do a linear search from the 6036059Samurai // last section to the first. 6046059Samurai bool Found = false; 6056059Samurai unsigned SecIdx = CPSections.size(); 6066735Samurai while (SecIdx != 0) { 6076059Samurai if (CPSections[--SecIdx].S == S) { 6086059Samurai Found = true; 6096059Samurai break; 6106059Samurai } 6116059Samurai } 6126059Samurai if (!Found) { 6136059Samurai SecIdx = CPSections.size(); 6146735Samurai CPSections.push_back(SectionCPs(S, Align)); 6156735Samurai } 6166735Samurai 6176059Samurai if (Align > CPSections[SecIdx].Alignment) 6186059Samurai CPSections[SecIdx].Alignment = Align; 6196059Samurai CPSections[SecIdx].CPEs.push_back(i); 6206735Samurai } 6216059Samurai 6226735Samurai // Now print stuff into the calculated sections. 6236735Samurai for (unsigned i = 0, e = CPSections.size(); i != e; ++i) { 6246059Samurai OutStreamer.SwitchSection(CPSections[i].S); 6256059Samurai EmitAlignment(Log2_32(CPSections[i].Alignment)); 6266059Samurai 6276059Samurai unsigned Offset = 0; 6286059Samurai for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) { 6296059Samurai unsigned CPI = CPSections[i].CPEs[j]; 6306059Samurai MachineConstantPoolEntry CPE = CP[CPI]; 6316059Samurai 6326059Samurai // Emit inter-object padding for alignment. 6336059Samurai unsigned AlignMask = CPE.getAlignment() - 1; 6346059Samurai unsigned NewOffset = (Offset + AlignMask) & ~AlignMask; 6356059Samurai OutStreamer.EmitFill(NewOffset - Offset, 0/*fillval*/, 0/*addrspace*/); 6366059Samurai 6376059Samurai const Type *Ty = CPE.getType(); 6386059Samurai Offset = NewOffset + TM.getTargetData()->getTypeAllocSize(Ty); 6396059Samurai 6406059Samurai // Emit the label with a comment on it. 6416059Samurai if (VerboseAsm) { 6426059Samurai OutStreamer.GetCommentOS() << "constant pool "; 6436059Samurai WriteTypeSymbolic(OutStreamer.GetCommentOS(), CPE.getType(), 6446059Samurai MF->getFunction()->getParent()); 6456059Samurai OutStreamer.GetCommentOS() << '\n'; 6466059Samurai } 6476764Samurai OutStreamer.EmitLabel(GetCPISymbol(CPI)); 6486764Samurai 6496764Samurai if (CPE.isMachineConstantPoolEntry()) 6506764Samurai EmitMachineConstantPoolValue(CPE.Val.MachineCPVal); 6516764Samurai else 6526764Samurai EmitGlobalConstant(CPE.Val.ConstVal); 6536764Samurai } 6546764Samurai } 6556764Samurai} 6566764Samurai 6576764Samurai/// EmitJumpTableInfo - Print assembly representations of the jump tables used 6586764Samurai/// by the current function to the current output stream. 6596059Samurai/// 6606059Samuraivoid AsmPrinter::EmitJumpTableInfo() { 6616059Samurai const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo(); 6626059Samurai if (MJTI == 0) return; 6636059Samurai if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return; 6646059Samurai const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables(); 6656059Samurai if (JT.empty()) return; 6666059Samurai 6676059Samurai // Pick the directive to use to print the jump table entries, and switch to 6686059Samurai // the appropriate section. 6696059Samurai const Function *F = MF->getFunction(); 6706059Samurai bool JTInDiffSection = false; 6716059Samurai if (// In PIC mode, we need to emit the jump table to the same section as the 6726735Samurai // function body itself, otherwise the label differences won't make sense. 6736735Samurai // FIXME: Need a better predicate for this: what about custom entries? 6746059Samurai MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 || 6756059Samurai // We should also do if the section name is NULL or function is declared 6766059Samurai // in discardable section 6776059Samurai // FIXME: this isn't the right predicate, should be based on the MCSection 6786059Samurai // for the function. 6796059Samurai F->isWeakForLinker()) { 6806059Samurai OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM)); 6816059Samurai } else { 6826059Samurai // Otherwise, drop it in the readonly section. 6836059Samurai const MCSection *ReadOnlySection = 6846059Samurai getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly()); 6856059Samurai OutStreamer.SwitchSection(ReadOnlySection); 6866059Samurai JTInDiffSection = true; 6876059Samurai } 6886059Samurai 6896059Samurai EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getTargetData()))); 6906059Samurai 6916059Samurai for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) { 6926059Samurai const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs; 6936059Samurai 6946059Samurai // If this jump table was deleted, ignore it. 6956059Samurai if (JTBBs.empty()) continue; 6966059Samurai 6976059Samurai // For the EK_LabelDifference32 entry, if the target supports .set, emit a 6986059Samurai // .set directive for each unique entry. This reduces the number of 6996059Samurai // relocations the assembler will generate for the jump table. 7006059Samurai if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 && 7016059Samurai MAI->hasSetDirective()) { 7026059Samurai SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets; 7036059Samurai const TargetLowering *TLI = TM.getTargetLowering(); 7046059Samurai const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext); 7056059Samurai for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) { 7066059Samurai const MachineBasicBlock *MBB = JTBBs[ii]; 7076059Samurai if (!EmittedSets.insert(MBB)) continue; 7086059Samurai 7096059Samurai // .set LJTSet, LBB32-base 7106059Samurai const MCExpr *LHS = 7116059Samurai MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext); 7126059Samurai OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()), 7136059Samurai MCBinaryExpr::CreateSub(LHS, Base, OutContext)); 7146059Samurai } 7156059Samurai } 7166059Samurai 7176059Samurai // On some targets (e.g. Darwin) we want to emit two consequtive labels 7186059Samurai // before each jump table. The first label is never referenced, but tells 7196059Samurai // the assembler and linker the extents of the jump table object. The 7206059Samurai // second label is actually referenced by the code. 7216059Samurai if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0]) 7226059Samurai // FIXME: This doesn't have to have any specific name, just any randomly 7236059Samurai // named and numbered 'l' label would work. Simplify GetJTISymbol. 7246059Samurai OutStreamer.EmitLabel(GetJTISymbol(JTI, true)); 7256059Samurai 7266059Samurai OutStreamer.EmitLabel(GetJTISymbol(JTI)); 7276059Samurai 7286059Samurai for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) 7296059Samurai EmitJumpTableEntry(MJTI, JTBBs[ii], JTI); 7306059Samurai } 7316059Samurai} 7326059Samurai 7336059Samurai/// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the 7346059Samurai/// current stream. 7356059Samuraivoid AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI, 7366059Samurai const MachineBasicBlock *MBB, 7376059Samurai unsigned UID) const { 7386059Samurai const MCExpr *Value = 0; 7396059Samurai switch (MJTI->getEntryKind()) { 7406059Samurai case MachineJumpTableInfo::EK_Inline: 7416059Samurai llvm_unreachable("Cannot emit EK_Inline jump table entry"); break; 7426059Samurai case MachineJumpTableInfo::EK_Custom32: 7436059Samurai Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID, 7446059Samurai OutContext); 7456059Samurai break; 7466735Samurai case MachineJumpTableInfo::EK_BlockAddress: 7476059Samurai // EK_BlockAddress - Each entry is a plain address of block, e.g.: 7486059Samurai // .word LBB123 7496059Samurai Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext); 7506059Samurai break; 7516059Samurai case MachineJumpTableInfo::EK_GPRel32BlockAddress: { 7526059Samurai // EK_GPRel32BlockAddress - Each entry is an address of block, encoded 7536059Samurai // with a relocation as gp-relative, e.g.: 7546059Samurai // .gprel32 LBB123 7556059Samurai MCSymbol *MBBSym = MBB->getSymbol(); 7566059Samurai OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext)); 7576059Samurai return; 7586059Samurai } 7596059Samurai 7606059Samurai case MachineJumpTableInfo::EK_LabelDifference32: { 7616059Samurai // EK_LabelDifference32 - Each entry is the address of the block minus 7626059Samurai // the address of the jump table. This is used for PIC jump tables where 7636059Samurai // gprel32 is not supported. e.g.: 7646735Samurai // .word LBB123 - LJTI1_2 7656735Samurai // If the .set directive is supported, this is emitted as: 7666735Samurai // .set L4_5_set_123, LBB123 - LJTI1_2 7676735Samurai // .word L4_5_set_123 7686735Samurai 7696059Samurai // If we have emitted set directives for the jump table entries, print 7706059Samurai // them rather than the entries themselves. If we're emitting PIC, then 771 // emit the table entries as differences between two text section labels. 772 if (MAI->hasSetDirective()) { 773 // If we used .set, reference the .set's symbol. 774 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()), 775 OutContext); 776 break; 777 } 778 // Otherwise, use the difference as the jump table entry. 779 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext); 780 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext); 781 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext); 782 break; 783 } 784 } 785 786 assert(Value && "Unknown entry kind!"); 787 788 unsigned EntrySize = MJTI->getEntrySize(*TM.getTargetData()); 789 OutStreamer.EmitValue(Value, EntrySize, /*addrspace*/0); 790} 791 792 793/// EmitSpecialLLVMGlobal - Check to see if the specified global is a 794/// special global used by LLVM. If so, emit it and return true, otherwise 795/// do nothing and return false. 796bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) { 797 if (GV->getName() == "llvm.used") { 798 if (MAI->hasNoDeadStrip()) // No need to emit this at all. 799 EmitLLVMUsedList(GV->getInitializer()); 800 return true; 801 } 802 803 // Ignore debug and non-emitted data. This handles llvm.compiler.used. 804 if (GV->getSection() == "llvm.metadata" || 805 GV->hasAvailableExternallyLinkage()) 806 return true; 807 808 if (!GV->hasAppendingLinkage()) return false; 809 810 assert(GV->hasInitializer() && "Not a special LLVM global!"); 811 812 const TargetData *TD = TM.getTargetData(); 813 unsigned Align = Log2_32(TD->getPointerPrefAlignment()); 814 if (GV->getName() == "llvm.global_ctors") { 815 OutStreamer.SwitchSection(getObjFileLowering().getStaticCtorSection()); 816 EmitAlignment(Align, 0); 817 EmitXXStructorList(GV->getInitializer()); 818 819 if (TM.getRelocationModel() == Reloc::Static && 820 MAI->hasStaticCtorDtorReferenceInStaticMode()) { 821 StringRef Sym(".constructors_used"); 822 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym), 823 MCSA_Reference); 824 } 825 return true; 826 } 827 828 if (GV->getName() == "llvm.global_dtors") { 829 OutStreamer.SwitchSection(getObjFileLowering().getStaticDtorSection()); 830 EmitAlignment(Align, 0); 831 EmitXXStructorList(GV->getInitializer()); 832 833 if (TM.getRelocationModel() == Reloc::Static && 834 MAI->hasStaticCtorDtorReferenceInStaticMode()) { 835 StringRef Sym(".destructors_used"); 836 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym), 837 MCSA_Reference); 838 } 839 return true; 840 } 841 842 return false; 843} 844 845/// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each 846/// global in the specified llvm.used list for which emitUsedDirectiveFor 847/// is true, as being used with this directive. 848void AsmPrinter::EmitLLVMUsedList(Constant *List) { 849 // Should be an array of 'i8*'. 850 ConstantArray *InitList = dyn_cast<ConstantArray>(List); 851 if (InitList == 0) return; 852 853 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) { 854 const GlobalValue *GV = 855 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts()); 856 if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang)) 857 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(GV), MCSA_NoDeadStrip); 858 } 859} 860 861/// EmitXXStructorList - Emit the ctor or dtor list. This just prints out the 862/// function pointers, ignoring the init priority. 863void AsmPrinter::EmitXXStructorList(Constant *List) { 864 // Should be an array of '{ int, void ()* }' structs. The first value is the 865 // init priority, which we ignore. 866 if (!isa<ConstantArray>(List)) return; 867 ConstantArray *InitList = cast<ConstantArray>(List); 868 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) 869 if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){ 870 if (CS->getNumOperands() != 2) return; // Not array of 2-element structs. 871 872 if (CS->getOperand(1)->isNullValue()) 873 return; // Found a null terminator, exit printing. 874 // Emit the function pointer. 875 EmitGlobalConstant(CS->getOperand(1)); 876 } 877} 878 879//===--------------------------------------------------------------------===// 880// Emission and print routines 881// 882 883/// EmitInt8 - Emit a byte directive and value. 884/// 885void AsmPrinter::EmitInt8(int Value) const { 886 OutStreamer.EmitIntValue(Value, 1, 0/*addrspace*/); 887} 888 889/// EmitInt16 - Emit a short directive and value. 890/// 891void AsmPrinter::EmitInt16(int Value) const { 892 OutStreamer.EmitIntValue(Value, 2, 0/*addrspace*/); 893} 894 895/// EmitInt32 - Emit a long directive and value. 896/// 897void AsmPrinter::EmitInt32(int Value) const { 898 OutStreamer.EmitIntValue(Value, 4, 0/*addrspace*/); 899} 900 901/// EmitInt64 - Emit a long long directive and value. 902/// 903void AsmPrinter::EmitInt64(uint64_t Value) const { 904 OutStreamer.EmitIntValue(Value, 8, 0/*addrspace*/); 905} 906 907/// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size 908/// in bytes of the directive is specified by Size and Hi/Lo specify the 909/// labels. This implicitly uses .set if it is available. 910void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo, 911 unsigned Size) const { 912 // Get the Hi-Lo expression. 913 const MCExpr *Diff = 914 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext), 915 MCSymbolRefExpr::Create(Lo, OutContext), 916 OutContext); 917 918 if (!MAI->hasSetDirective()) { 919 OutStreamer.EmitValue(Diff, Size, 0/*AddrSpace*/); 920 return; 921 } 922 923 // Otherwise, emit with .set (aka assignment). 924 MCSymbol *SetLabel = 925 OutContext.GetOrCreateTemporarySymbol(Twine(MAI->getPrivateGlobalPrefix()) + 926 "set" + Twine(SetCounter++)); 927 OutStreamer.EmitAssignment(SetLabel, Diff); 928 OutStreamer.EmitSymbolValue(SetLabel, Size, 0/*AddrSpace*/); 929} 930 931 932//===----------------------------------------------------------------------===// 933 934// EmitAlignment - Emit an alignment directive to the specified power of 935// two boundary. For example, if you pass in 3 here, you will get an 8 936// byte alignment. If a global value is specified, and if that global has 937// an explicit alignment requested, it will unconditionally override the 938// alignment request. However, if ForcedAlignBits is specified, this value 939// has final say: the ultimate alignment will be the max of ForcedAlignBits 940// and the alignment computed with NumBits and the global. 941// 942// The algorithm is: 943// Align = NumBits; 944// if (GV && GV->hasalignment) Align = GV->getalignment(); 945// Align = std::max(Align, ForcedAlignBits); 946// 947void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV, 948 unsigned ForcedAlignBits, 949 bool UseFillExpr) const { 950 if (GV && GV->getAlignment()) 951 NumBits = Log2_32(GV->getAlignment()); 952 NumBits = std::max(NumBits, ForcedAlignBits); 953 954 if (NumBits == 0) return; // No need to emit alignment. 955 956 if (getCurrentSection()->getKind().isText()) 957 OutStreamer.EmitCodeAlignment(1 << NumBits); 958 else 959 OutStreamer.EmitValueToAlignment(1 << NumBits, 0, 1, 0); 960} 961 962/// LowerConstant - Lower the specified LLVM Constant to an MCExpr. 963/// 964static const MCExpr *LowerConstant(const Constant *CV, AsmPrinter &AP) { 965 MCContext &Ctx = AP.OutContext; 966 967 if (CV->isNullValue() || isa<UndefValue>(CV)) 968 return MCConstantExpr::Create(0, Ctx); 969 970 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) 971 return MCConstantExpr::Create(CI->getZExtValue(), Ctx); 972 973 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV)) 974 return MCSymbolRefExpr::Create(AP.Mang->getSymbol(GV), Ctx); 975 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV)) 976 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx); 977 978 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV); 979 if (CE == 0) { 980 llvm_unreachable("Unknown constant value to lower!"); 981 return MCConstantExpr::Create(0, Ctx); 982 } 983 984 switch (CE->getOpcode()) { 985 default: 986 // If the code isn't optimized, there may be outstanding folding 987 // opportunities. Attempt to fold the expression using TargetData as a 988 // last resort before giving up. 989 if (Constant *C = 990 ConstantFoldConstantExpression(CE, AP.TM.getTargetData())) 991 if (C != CE) 992 return LowerConstant(C, AP); 993#ifndef NDEBUG 994 CE->dump(); 995#endif 996 llvm_unreachable("FIXME: Don't support this constant expr"); 997 case Instruction::GetElementPtr: { 998 const TargetData &TD = *AP.TM.getTargetData(); 999 // Generate a symbolic expression for the byte address 1000 const Constant *PtrVal = CE->getOperand(0); 1001 SmallVector<Value*, 8> IdxVec(CE->op_begin()+1, CE->op_end()); 1002 int64_t Offset = TD.getIndexedOffset(PtrVal->getType(), &IdxVec[0], 1003 IdxVec.size()); 1004 1005 const MCExpr *Base = LowerConstant(CE->getOperand(0), AP); 1006 if (Offset == 0) 1007 return Base; 1008 1009 // Truncate/sext the offset to the pointer size. 1010 if (TD.getPointerSizeInBits() != 64) { 1011 int SExtAmount = 64-TD.getPointerSizeInBits(); 1012 Offset = (Offset << SExtAmount) >> SExtAmount; 1013 } 1014 1015 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx), 1016 Ctx); 1017 } 1018 1019 case Instruction::Trunc: 1020 // We emit the value and depend on the assembler to truncate the generated 1021 // expression properly. This is important for differences between 1022 // blockaddress labels. Since the two labels are in the same function, it 1023 // is reasonable to treat their delta as a 32-bit value. 1024 // FALL THROUGH. 1025 case Instruction::BitCast: 1026 return LowerConstant(CE->getOperand(0), AP); 1027 1028 case Instruction::IntToPtr: { 1029 const TargetData &TD = *AP.TM.getTargetData(); 1030 // Handle casts to pointers by changing them into casts to the appropriate 1031 // integer type. This promotes constant folding and simplifies this code. 1032 Constant *Op = CE->getOperand(0); 1033 Op = ConstantExpr::getIntegerCast(Op, TD.getIntPtrType(CV->getContext()), 1034 false/*ZExt*/); 1035 return LowerConstant(Op, AP); 1036 } 1037 1038 case Instruction::PtrToInt: { 1039 const TargetData &TD = *AP.TM.getTargetData(); 1040 // Support only foldable casts to/from pointers that can be eliminated by 1041 // changing the pointer to the appropriately sized integer type. 1042 Constant *Op = CE->getOperand(0); 1043 const Type *Ty = CE->getType(); 1044 1045 const MCExpr *OpExpr = LowerConstant(Op, AP); 1046 1047 // We can emit the pointer value into this slot if the slot is an 1048 // integer slot equal to the size of the pointer. 1049 if (TD.getTypeAllocSize(Ty) == TD.getTypeAllocSize(Op->getType())) 1050 return OpExpr; 1051 1052 // Otherwise the pointer is smaller than the resultant integer, mask off 1053 // the high bits so we are sure to get a proper truncation if the input is 1054 // a constant expr. 1055 unsigned InBits = TD.getTypeAllocSizeInBits(Op->getType()); 1056 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx); 1057 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx); 1058 } 1059 1060 // The MC library also has a right-shift operator, but it isn't consistently 1061 // signed or unsigned between different targets. 1062 case Instruction::Add: 1063 case Instruction::Sub: 1064 case Instruction::Mul: 1065 case Instruction::SDiv: 1066 case Instruction::SRem: 1067 case Instruction::Shl: 1068 case Instruction::And: 1069 case Instruction::Or: 1070 case Instruction::Xor: { 1071 const MCExpr *LHS = LowerConstant(CE->getOperand(0), AP); 1072 const MCExpr *RHS = LowerConstant(CE->getOperand(1), AP); 1073 switch (CE->getOpcode()) { 1074 default: llvm_unreachable("Unknown binary operator constant cast expr"); 1075 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx); 1076 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx); 1077 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx); 1078 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx); 1079 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx); 1080 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx); 1081 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx); 1082 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx); 1083 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx); 1084 } 1085 } 1086 } 1087} 1088 1089static void EmitGlobalConstantArray(const ConstantArray *CA, unsigned AddrSpace, 1090 AsmPrinter &AP) { 1091 if (AddrSpace != 0 || !CA->isString()) { 1092 // Not a string. Print the values in successive locations 1093 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i) 1094 AP.EmitGlobalConstant(CA->getOperand(i), AddrSpace); 1095 return; 1096 } 1097 1098 // Otherwise, it can be emitted as .ascii. 1099 SmallVector<char, 128> TmpVec; 1100 TmpVec.reserve(CA->getNumOperands()); 1101 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i) 1102 TmpVec.push_back(cast<ConstantInt>(CA->getOperand(i))->getZExtValue()); 1103 1104 AP.OutStreamer.EmitBytes(StringRef(TmpVec.data(), TmpVec.size()), AddrSpace); 1105} 1106 1107static void EmitGlobalConstantVector(const ConstantVector *CV, 1108 unsigned AddrSpace, AsmPrinter &AP) { 1109 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i) 1110 AP.EmitGlobalConstant(CV->getOperand(i), AddrSpace); 1111} 1112 1113static void EmitGlobalConstantStruct(const ConstantStruct *CS, 1114 unsigned AddrSpace, AsmPrinter &AP) { 1115 // Print the fields in successive locations. Pad to align if needed! 1116 const TargetData *TD = AP.TM.getTargetData(); 1117 unsigned Size = TD->getTypeAllocSize(CS->getType()); 1118 const StructLayout *Layout = TD->getStructLayout(CS->getType()); 1119 uint64_t SizeSoFar = 0; 1120 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) { 1121 const Constant *Field = CS->getOperand(i); 1122 1123 // Check if padding is needed and insert one or more 0s. 1124 uint64_t FieldSize = TD->getTypeAllocSize(Field->getType()); 1125 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1)) 1126 - Layout->getElementOffset(i)) - FieldSize; 1127 SizeSoFar += FieldSize + PadSize; 1128 1129 // Now print the actual field value. 1130 AP.EmitGlobalConstant(Field, AddrSpace); 1131 1132 // Insert padding - this may include padding to increase the size of the 1133 // current field up to the ABI size (if the struct is not packed) as well 1134 // as padding to ensure that the next field starts at the right offset. 1135 AP.OutStreamer.EmitZeros(PadSize, AddrSpace); 1136 } 1137 assert(SizeSoFar == Layout->getSizeInBytes() && 1138 "Layout of constant struct may be incorrect!"); 1139} 1140 1141static void EmitGlobalConstantUnion(const ConstantUnion *CU, 1142 unsigned AddrSpace, AsmPrinter &AP) { 1143 const TargetData *TD = AP.TM.getTargetData(); 1144 unsigned Size = TD->getTypeAllocSize(CU->getType()); 1145 1146 const Constant *Contents = CU->getOperand(0); 1147 unsigned FilledSize = TD->getTypeAllocSize(Contents->getType()); 1148 1149 // Print the actually filled part 1150 AP.EmitGlobalConstant(Contents, AddrSpace); 1151 1152 // And pad with enough zeroes 1153 AP.OutStreamer.EmitZeros(Size-FilledSize, AddrSpace); 1154} 1155 1156static void EmitGlobalConstantFP(const ConstantFP *CFP, unsigned AddrSpace, 1157 AsmPrinter &AP) { 1158 // FP Constants are printed as integer constants to avoid losing 1159 // precision. 1160 if (CFP->getType()->isDoubleTy()) { 1161 if (AP.VerboseAsm) { 1162 double Val = CFP->getValueAPF().convertToDouble(); 1163 AP.OutStreamer.GetCommentOS() << "double " << Val << '\n'; 1164 } 1165 1166 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue(); 1167 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace); 1168 return; 1169 } 1170 1171 if (CFP->getType()->isFloatTy()) { 1172 if (AP.VerboseAsm) { 1173 float Val = CFP->getValueAPF().convertToFloat(); 1174 AP.OutStreamer.GetCommentOS() << "float " << Val << '\n'; 1175 } 1176 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue(); 1177 AP.OutStreamer.EmitIntValue(Val, 4, AddrSpace); 1178 return; 1179 } 1180 1181 if (CFP->getType()->isX86_FP80Ty()) { 1182 // all long double variants are printed as hex 1183 // api needed to prevent premature destruction 1184 APInt API = CFP->getValueAPF().bitcastToAPInt(); 1185 const uint64_t *p = API.getRawData(); 1186 if (AP.VerboseAsm) { 1187 // Convert to double so we can print the approximate val as a comment. 1188 APFloat DoubleVal = CFP->getValueAPF(); 1189 bool ignored; 1190 DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven, 1191 &ignored); 1192 AP.OutStreamer.GetCommentOS() << "x86_fp80 ~= " 1193 << DoubleVal.convertToDouble() << '\n'; 1194 } 1195 1196 if (AP.TM.getTargetData()->isBigEndian()) { 1197 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace); 1198 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace); 1199 } else { 1200 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace); 1201 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace); 1202 } 1203 1204 // Emit the tail padding for the long double. 1205 const TargetData &TD = *AP.TM.getTargetData(); 1206 AP.OutStreamer.EmitZeros(TD.getTypeAllocSize(CFP->getType()) - 1207 TD.getTypeStoreSize(CFP->getType()), AddrSpace); 1208 return; 1209 } 1210 1211 assert(CFP->getType()->isPPC_FP128Ty() && 1212 "Floating point constant type not handled"); 1213 // All long double variants are printed as hex api needed to prevent 1214 // premature destruction. 1215 APInt API = CFP->getValueAPF().bitcastToAPInt(); 1216 const uint64_t *p = API.getRawData(); 1217 if (AP.TM.getTargetData()->isBigEndian()) { 1218 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace); 1219 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace); 1220 } else { 1221 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace); 1222 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace); 1223 } 1224} 1225 1226static void EmitGlobalConstantLargeInt(const ConstantInt *CI, 1227 unsigned AddrSpace, AsmPrinter &AP) { 1228 const TargetData *TD = AP.TM.getTargetData(); 1229 unsigned BitWidth = CI->getBitWidth(); 1230 assert((BitWidth & 63) == 0 && "only support multiples of 64-bits"); 1231 1232 // We don't expect assemblers to support integer data directives 1233 // for more than 64 bits, so we emit the data in at most 64-bit 1234 // quantities at a time. 1235 const uint64_t *RawData = CI->getValue().getRawData(); 1236 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) { 1237 uint64_t Val = TD->isBigEndian() ? RawData[e - i - 1] : RawData[i]; 1238 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace); 1239 } 1240} 1241 1242/// EmitGlobalConstant - Print a general LLVM constant to the .s file. 1243void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) { 1244 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV)) { 1245 uint64_t Size = TM.getTargetData()->getTypeAllocSize(CV->getType()); 1246 if (Size == 0) Size = 1; // An empty "_foo:" followed by a section is undef. 1247 return OutStreamer.EmitZeros(Size, AddrSpace); 1248 } 1249 1250 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) { 1251 unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType()); 1252 switch (Size) { 1253 case 1: 1254 case 2: 1255 case 4: 1256 case 8: 1257 if (VerboseAsm) 1258 OutStreamer.GetCommentOS() << format("0x%llx\n", CI->getZExtValue()); 1259 OutStreamer.EmitIntValue(CI->getZExtValue(), Size, AddrSpace); 1260 return; 1261 default: 1262 EmitGlobalConstantLargeInt(CI, AddrSpace, *this); 1263 return; 1264 } 1265 } 1266 1267 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV)) 1268 return EmitGlobalConstantArray(CVA, AddrSpace, *this); 1269 1270 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV)) 1271 return EmitGlobalConstantStruct(CVS, AddrSpace, *this); 1272 1273 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV)) 1274 return EmitGlobalConstantFP(CFP, AddrSpace, *this); 1275 1276 if (isa<ConstantPointerNull>(CV)) { 1277 unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType()); 1278 OutStreamer.EmitIntValue(0, Size, AddrSpace); 1279 return; 1280 } 1281 1282 if (const ConstantUnion *CVU = dyn_cast<ConstantUnion>(CV)) 1283 return EmitGlobalConstantUnion(CVU, AddrSpace, *this); 1284 1285 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV)) 1286 return EmitGlobalConstantVector(V, AddrSpace, *this); 1287 1288 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it 1289 // thread the streamer with EmitValue. 1290 OutStreamer.EmitValue(LowerConstant(CV, *this), 1291 TM.getTargetData()->getTypeAllocSize(CV->getType()), 1292 AddrSpace); 1293} 1294 1295void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) { 1296 // Target doesn't support this yet! 1297 llvm_unreachable("Target does not support EmitMachineConstantPoolValue"); 1298} 1299 1300/// PrintSpecial - Print information related to the specified machine instr 1301/// that is independent of the operand, and may be independent of the instr 1302/// itself. This can be useful for portably encoding the comment character 1303/// or other bits of target-specific knowledge into the asmstrings. The 1304/// syntax used is ${:comment}. Targets can override this to add support 1305/// for their own strange codes. 1306void AsmPrinter::PrintSpecial(const MachineInstr *MI, const char *Code) const { 1307 if (!strcmp(Code, "private")) { 1308 O << MAI->getPrivateGlobalPrefix(); 1309 } else if (!strcmp(Code, "comment")) { 1310 if (VerboseAsm) 1311 O << MAI->getCommentString(); 1312 } else if (!strcmp(Code, "uid")) { 1313 // Comparing the address of MI isn't sufficient, because machineinstrs may 1314 // be allocated to the same address across functions. 1315 const Function *ThisF = MI->getParent()->getParent()->getFunction(); 1316 1317 // If this is a new LastFn instruction, bump the counter. 1318 if (LastMI != MI || LastFn != ThisF) { 1319 ++Counter; 1320 LastMI = MI; 1321 LastFn = ThisF; 1322 } 1323 O << Counter; 1324 } else { 1325 std::string msg; 1326 raw_string_ostream Msg(msg); 1327 Msg << "Unknown special formatter '" << Code 1328 << "' for machine instr: " << *MI; 1329 llvm_report_error(Msg.str()); 1330 } 1331} 1332 1333/// processDebugLoc - Processes the debug information of each machine 1334/// instruction's DebugLoc. 1335void AsmPrinter::processDebugLoc(const MachineInstr *MI, 1336 bool BeforePrintingInsn) { 1337 if (!MAI || !DW || !MAI->doesSupportDebugInformation() 1338 || !DW->ShouldEmitDwarfDebug()) 1339 return; 1340 if (MI->getOpcode() == TargetOpcode::DBG_VALUE) 1341 return; 1342 DebugLoc DL = MI->getDebugLoc(); 1343 if (DL.isUnknown()) 1344 return; 1345 DILocation CurDLT = MF->getDILocation(DL); 1346 if (!CurDLT.getScope().Verify()) 1347 return; 1348 1349 if (!BeforePrintingInsn) { 1350 // After printing instruction 1351 DW->EndScope(MI); 1352 } else if (CurDLT.getNode() != PrevDLT) { 1353 MCSymbol *L = DW->RecordSourceLine(CurDLT.getLineNumber(), 1354 CurDLT.getColumnNumber(), 1355 CurDLT.getScope().getNode()); 1356 DW->BeginScope(MI, L); 1357 PrevDLT = CurDLT.getNode(); 1358 } 1359} 1360 1361 1362/// printInlineAsm - This method formats and prints the specified machine 1363/// instruction that is an inline asm. 1364void AsmPrinter::printInlineAsm(const MachineInstr *MI) const { 1365 unsigned NumOperands = MI->getNumOperands(); 1366 1367 // Count the number of register definitions. 1368 unsigned NumDefs = 0; 1369 for (; MI->getOperand(NumDefs).isReg() && MI->getOperand(NumDefs).isDef(); 1370 ++NumDefs) 1371 assert(NumDefs != NumOperands-1 && "No asm string?"); 1372 1373 assert(MI->getOperand(NumDefs).isSymbol() && "No asm string?"); 1374 1375 // Disassemble the AsmStr, printing out the literal pieces, the operands, etc. 1376 const char *AsmStr = MI->getOperand(NumDefs).getSymbolName(); 1377 1378 O << '\t'; 1379 1380 // If this asmstr is empty, just print the #APP/#NOAPP markers. 1381 // These are useful to see where empty asm's wound up. 1382 if (AsmStr[0] == 0) { 1383 O << MAI->getCommentString() << MAI->getInlineAsmStart() << "\n\t"; 1384 O << MAI->getCommentString() << MAI->getInlineAsmEnd() << '\n'; 1385 return; 1386 } 1387 1388 O << MAI->getCommentString() << MAI->getInlineAsmStart() << "\n\t"; 1389 1390 // The variant of the current asmprinter. 1391 int AsmPrinterVariant = MAI->getAssemblerDialect(); 1392 1393 int CurVariant = -1; // The number of the {.|.|.} region we are in. 1394 const char *LastEmitted = AsmStr; // One past the last character emitted. 1395 1396 while (*LastEmitted) { 1397 switch (*LastEmitted) { 1398 default: { 1399 // Not a special case, emit the string section literally. 1400 const char *LiteralEnd = LastEmitted+1; 1401 while (*LiteralEnd && *LiteralEnd != '{' && *LiteralEnd != '|' && 1402 *LiteralEnd != '}' && *LiteralEnd != '$' && *LiteralEnd != '\n') 1403 ++LiteralEnd; 1404 if (CurVariant == -1 || CurVariant == AsmPrinterVariant) 1405 O.write(LastEmitted, LiteralEnd-LastEmitted); 1406 LastEmitted = LiteralEnd; 1407 break; 1408 } 1409 case '\n': 1410 ++LastEmitted; // Consume newline character. 1411 O << '\n'; // Indent code with newline. 1412 break; 1413 case '$': { 1414 ++LastEmitted; // Consume '$' character. 1415 bool Done = true; 1416 1417 // Handle escapes. 1418 switch (*LastEmitted) { 1419 default: Done = false; break; 1420 case '$': // $$ -> $ 1421 if (CurVariant == -1 || CurVariant == AsmPrinterVariant) 1422 O << '$'; 1423 ++LastEmitted; // Consume second '$' character. 1424 break; 1425 case '(': // $( -> same as GCC's { character. 1426 ++LastEmitted; // Consume '(' character. 1427 if (CurVariant != -1) { 1428 llvm_report_error("Nested variants found in inline asm string: '" 1429 + std::string(AsmStr) + "'"); 1430 } 1431 CurVariant = 0; // We're in the first variant now. 1432 break; 1433 case '|': 1434 ++LastEmitted; // consume '|' character. 1435 if (CurVariant == -1) 1436 O << '|'; // this is gcc's behavior for | outside a variant 1437 else 1438 ++CurVariant; // We're in the next variant. 1439 break; 1440 case ')': // $) -> same as GCC's } char. 1441 ++LastEmitted; // consume ')' character. 1442 if (CurVariant == -1) 1443 O << '}'; // this is gcc's behavior for } outside a variant 1444 else 1445 CurVariant = -1; 1446 break; 1447 } 1448 if (Done) break; 1449 1450 bool HasCurlyBraces = false; 1451 if (*LastEmitted == '{') { // ${variable} 1452 ++LastEmitted; // Consume '{' character. 1453 HasCurlyBraces = true; 1454 } 1455 1456 // If we have ${:foo}, then this is not a real operand reference, it is a 1457 // "magic" string reference, just like in .td files. Arrange to call 1458 // PrintSpecial. 1459 if (HasCurlyBraces && *LastEmitted == ':') { 1460 ++LastEmitted; 1461 const char *StrStart = LastEmitted; 1462 const char *StrEnd = strchr(StrStart, '}'); 1463 if (StrEnd == 0) { 1464 llvm_report_error("Unterminated ${:foo} operand in inline asm string: '" 1465 + std::string(AsmStr) + "'"); 1466 } 1467 1468 std::string Val(StrStart, StrEnd); 1469 PrintSpecial(MI, Val.c_str()); 1470 LastEmitted = StrEnd+1; 1471 break; 1472 } 1473 1474 const char *IDStart = LastEmitted; 1475 char *IDEnd; 1476 errno = 0; 1477 long Val = strtol(IDStart, &IDEnd, 10); // We only accept numbers for IDs. 1478 if (!isdigit(*IDStart) || (Val == 0 && errno == EINVAL)) { 1479 llvm_report_error("Bad $ operand number in inline asm string: '" 1480 + std::string(AsmStr) + "'"); 1481 } 1482 LastEmitted = IDEnd; 1483 1484 char Modifier[2] = { 0, 0 }; 1485 1486 if (HasCurlyBraces) { 1487 // If we have curly braces, check for a modifier character. This 1488 // supports syntax like ${0:u}, which correspond to "%u0" in GCC asm. 1489 if (*LastEmitted == ':') { 1490 ++LastEmitted; // Consume ':' character. 1491 if (*LastEmitted == 0) { 1492 llvm_report_error("Bad ${:} expression in inline asm string: '" 1493 + std::string(AsmStr) + "'"); 1494 } 1495 1496 Modifier[0] = *LastEmitted; 1497 ++LastEmitted; // Consume modifier character. 1498 } 1499 1500 if (*LastEmitted != '}') { 1501 llvm_report_error("Bad ${} expression in inline asm string: '" 1502 + std::string(AsmStr) + "'"); 1503 } 1504 ++LastEmitted; // Consume '}' character. 1505 } 1506 1507 if ((unsigned)Val >= NumOperands-1) { 1508 llvm_report_error("Invalid $ operand number in inline asm string: '" 1509 + std::string(AsmStr) + "'"); 1510 } 1511 1512 // Okay, we finally have a value number. Ask the target to print this 1513 // operand! 1514 if (CurVariant == -1 || CurVariant == AsmPrinterVariant) { 1515 unsigned OpNo = 1; 1516 1517 bool Error = false; 1518 1519 // Scan to find the machine operand number for the operand. 1520 for (; Val; --Val) { 1521 if (OpNo >= MI->getNumOperands()) break; 1522 unsigned OpFlags = MI->getOperand(OpNo).getImm(); 1523 OpNo += InlineAsm::getNumOperandRegisters(OpFlags) + 1; 1524 } 1525 1526 if (OpNo >= MI->getNumOperands()) { 1527 Error = true; 1528 } else { 1529 unsigned OpFlags = MI->getOperand(OpNo).getImm(); 1530 ++OpNo; // Skip over the ID number. 1531 1532 if (Modifier[0] == 'l') // labels are target independent 1533 O << *MI->getOperand(OpNo).getMBB()->getSymbol(); 1534 else { 1535 AsmPrinter *AP = const_cast<AsmPrinter*>(this); 1536 if ((OpFlags & 7) == 4) { 1537 Error = AP->PrintAsmMemoryOperand(MI, OpNo, AsmPrinterVariant, 1538 Modifier[0] ? Modifier : 0); 1539 } else { 1540 Error = AP->PrintAsmOperand(MI, OpNo, AsmPrinterVariant, 1541 Modifier[0] ? Modifier : 0); 1542 } 1543 } 1544 } 1545 if (Error) { 1546 std::string msg; 1547 raw_string_ostream Msg(msg); 1548 Msg << "Invalid operand found in inline asm: '" << AsmStr << "'\n"; 1549 MI->print(Msg); 1550 llvm_report_error(Msg.str()); 1551 } 1552 } 1553 break; 1554 } 1555 } 1556 } 1557 O << "\n\t" << MAI->getCommentString() << MAI->getInlineAsmEnd(); 1558 OutStreamer.AddBlankLine(); 1559} 1560 1561/// printImplicitDef - This method prints the specified machine instruction 1562/// that is an implicit def. 1563void AsmPrinter::printImplicitDef(const MachineInstr *MI) const { 1564 if (!VerboseAsm) return; 1565 O.PadToColumn(MAI->getCommentColumn()); 1566 O << MAI->getCommentString() << " implicit-def: " 1567 << TRI->getName(MI->getOperand(0).getReg()); 1568 OutStreamer.AddBlankLine(); 1569} 1570 1571void AsmPrinter::printKill(const MachineInstr *MI) const { 1572 if (!VerboseAsm) return; 1573 O.PadToColumn(MAI->getCommentColumn()); 1574 O << MAI->getCommentString() << " kill:"; 1575 for (unsigned n = 0, e = MI->getNumOperands(); n != e; ++n) { 1576 const MachineOperand &op = MI->getOperand(n); 1577 assert(op.isReg() && "KILL instruction must have only register operands"); 1578 O << ' ' << TRI->getName(op.getReg()) << (op.isDef() ? "<def>" : "<kill>"); 1579 } 1580 OutStreamer.AddBlankLine(); 1581} 1582 1583/// printLabel - This method prints a local label used by debug and 1584/// exception handling tables. 1585void AsmPrinter::printLabelInst(const MachineInstr *MI) const { 1586 OutStreamer.EmitLabel(MI->getOperand(0).getMCSymbol()); 1587} 1588 1589/// PrintAsmOperand - Print the specified operand of MI, an INLINEASM 1590/// instruction, using the specified assembler variant. Targets should 1591/// override this to format as appropriate. 1592bool AsmPrinter::PrintAsmOperand(const MachineInstr *MI, unsigned OpNo, 1593 unsigned AsmVariant, const char *ExtraCode) { 1594 // Target doesn't support this yet! 1595 return true; 1596} 1597 1598bool AsmPrinter::PrintAsmMemoryOperand(const MachineInstr *MI, unsigned OpNo, 1599 unsigned AsmVariant, 1600 const char *ExtraCode) { 1601 // Target doesn't support this yet! 1602 return true; 1603} 1604 1605MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const { 1606 return MMI->getAddrLabelSymbol(BA->getBasicBlock()); 1607} 1608 1609MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const { 1610 return MMI->getAddrLabelSymbol(BB); 1611} 1612 1613/// GetCPISymbol - Return the symbol for the specified constant pool entry. 1614MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const { 1615 return OutContext.GetOrCreateTemporarySymbol 1616 (Twine(MAI->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber()) 1617 + "_" + Twine(CPID)); 1618} 1619 1620/// GetJTISymbol - Return the symbol for the specified jump table entry. 1621MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const { 1622 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate); 1623} 1624 1625/// GetJTSetSymbol - Return the symbol for the specified jump table .set 1626/// FIXME: privatize to AsmPrinter. 1627MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const { 1628 return OutContext.GetOrCreateTemporarySymbol 1629 (Twine(MAI->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" + 1630 Twine(UID) + "_set_" + Twine(MBBID)); 1631} 1632 1633/// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with 1634/// global value name as its base, with the specified suffix, and where the 1635/// symbol is forced to have private linkage if ForcePrivate is true. 1636MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV, 1637 StringRef Suffix, 1638 bool ForcePrivate) const { 1639 SmallString<60> NameStr; 1640 Mang->getNameWithPrefix(NameStr, GV, ForcePrivate); 1641 NameStr.append(Suffix.begin(), Suffix.end()); 1642 if (!GV->hasPrivateLinkage() && !ForcePrivate) 1643 return OutContext.GetOrCreateSymbol(NameStr.str()); 1644 return OutContext.GetOrCreateTemporarySymbol(NameStr.str()); 1645} 1646 1647/// GetExternalSymbolSymbol - Return the MCSymbol for the specified 1648/// ExternalSymbol. 1649MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const { 1650 SmallString<60> NameStr; 1651 Mang->getNameWithPrefix(NameStr, Sym); 1652 return OutContext.GetOrCreateSymbol(NameStr.str()); 1653} 1654 1655 1656 1657/// PrintParentLoopComment - Print comments about parent loops of this one. 1658static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop, 1659 unsigned FunctionNumber) { 1660 if (Loop == 0) return; 1661 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber); 1662 OS.indent(Loop->getLoopDepth()*2) 1663 << "Parent Loop BB" << FunctionNumber << "_" 1664 << Loop->getHeader()->getNumber() 1665 << " Depth=" << Loop->getLoopDepth() << '\n'; 1666} 1667 1668 1669/// PrintChildLoopComment - Print comments about child loops within 1670/// the loop for this basic block, with nesting. 1671static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop, 1672 unsigned FunctionNumber) { 1673 // Add child loop information 1674 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){ 1675 OS.indent((*CL)->getLoopDepth()*2) 1676 << "Child Loop BB" << FunctionNumber << "_" 1677 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth() 1678 << '\n'; 1679 PrintChildLoopComment(OS, *CL, FunctionNumber); 1680 } 1681} 1682 1683/// PrintBasicBlockLoopComments - Pretty-print comments for basic blocks. 1684static void PrintBasicBlockLoopComments(const MachineBasicBlock &MBB, 1685 const MachineLoopInfo *LI, 1686 const AsmPrinter &AP) { 1687 // Add loop depth information 1688 const MachineLoop *Loop = LI->getLoopFor(&MBB); 1689 if (Loop == 0) return; 1690 1691 MachineBasicBlock *Header = Loop->getHeader(); 1692 assert(Header && "No header for loop"); 1693 1694 // If this block is not a loop header, just print out what is the loop header 1695 // and return. 1696 if (Header != &MBB) { 1697 AP.OutStreamer.AddComment(" in Loop: Header=BB" + 1698 Twine(AP.getFunctionNumber())+"_" + 1699 Twine(Loop->getHeader()->getNumber())+ 1700 " Depth="+Twine(Loop->getLoopDepth())); 1701 return; 1702 } 1703 1704 // Otherwise, it is a loop header. Print out information about child and 1705 // parent loops. 1706 raw_ostream &OS = AP.OutStreamer.GetCommentOS(); 1707 1708 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber()); 1709 1710 OS << "=>"; 1711 OS.indent(Loop->getLoopDepth()*2-2); 1712 1713 OS << "This "; 1714 if (Loop->empty()) 1715 OS << "Inner "; 1716 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n'; 1717 1718 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber()); 1719} 1720 1721 1722/// EmitBasicBlockStart - This method prints the label for the specified 1723/// MachineBasicBlock, an alignment (if present) and a comment describing 1724/// it if appropriate. 1725void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const { 1726 // Emit an alignment directive for this block, if needed. 1727 if (unsigned Align = MBB->getAlignment()) 1728 EmitAlignment(Log2_32(Align)); 1729 1730 // If the block has its address taken, emit any labels that were used to 1731 // reference the block. It is possible that there is more than one label 1732 // here, because multiple LLVM BB's may have been RAUW'd to this block after 1733 // the references were generated. 1734 if (MBB->hasAddressTaken()) { 1735 const BasicBlock *BB = MBB->getBasicBlock(); 1736 if (VerboseAsm) 1737 OutStreamer.AddComment("Block address taken"); 1738 1739 std::vector<MCSymbol*> Syms = MMI->getAddrLabelSymbolToEmit(BB); 1740 1741 for (unsigned i = 0, e = Syms.size(); i != e; ++i) 1742 OutStreamer.EmitLabel(Syms[i]); 1743 } 1744 1745 // Print the main label for the block. 1746 if (MBB->pred_empty() || isBlockOnlyReachableByFallthrough(MBB)) { 1747 if (VerboseAsm) { 1748 // NOTE: Want this comment at start of line. 1749 O << MAI->getCommentString() << " BB#" << MBB->getNumber() << ':'; 1750 if (const BasicBlock *BB = MBB->getBasicBlock()) 1751 if (BB->hasName()) 1752 OutStreamer.AddComment("%" + BB->getName()); 1753 1754 PrintBasicBlockLoopComments(*MBB, LI, *this); 1755 OutStreamer.AddBlankLine(); 1756 } 1757 } else { 1758 if (VerboseAsm) { 1759 if (const BasicBlock *BB = MBB->getBasicBlock()) 1760 if (BB->hasName()) 1761 OutStreamer.AddComment("%" + BB->getName()); 1762 PrintBasicBlockLoopComments(*MBB, LI, *this); 1763 } 1764 1765 OutStreamer.EmitLabel(MBB->getSymbol()); 1766 } 1767} 1768 1769void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility) const { 1770 MCSymbolAttr Attr = MCSA_Invalid; 1771 1772 switch (Visibility) { 1773 default: break; 1774 case GlobalValue::HiddenVisibility: 1775 Attr = MAI->getHiddenVisibilityAttr(); 1776 break; 1777 case GlobalValue::ProtectedVisibility: 1778 Attr = MAI->getProtectedVisibilityAttr(); 1779 break; 1780 } 1781 1782 if (Attr != MCSA_Invalid) 1783 OutStreamer.EmitSymbolAttribute(Sym, Attr); 1784} 1785 1786void AsmPrinter::printOffset(int64_t Offset) const { 1787 if (Offset > 0) 1788 O << '+' << Offset; 1789 else if (Offset < 0) 1790 O << Offset; 1791} 1792 1793/// isBlockOnlyReachableByFallthough - Return true if the basic block has 1794/// exactly one predecessor and the control transfer mechanism between 1795/// the predecessor and this block is a fall-through. 1796bool AsmPrinter::isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) 1797 const { 1798 // If this is a landing pad, it isn't a fall through. If it has no preds, 1799 // then nothing falls through to it. 1800 if (MBB->isLandingPad() || MBB->pred_empty()) 1801 return false; 1802 1803 // If there isn't exactly one predecessor, it can't be a fall through. 1804 MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI; 1805 ++PI2; 1806 if (PI2 != MBB->pred_end()) 1807 return false; 1808 1809 // The predecessor has to be immediately before this block. 1810 const MachineBasicBlock *Pred = *PI; 1811 1812 if (!Pred->isLayoutSuccessor(MBB)) 1813 return false; 1814 1815 // If the block is completely empty, then it definitely does fall through. 1816 if (Pred->empty()) 1817 return true; 1818 1819 // Otherwise, check the last instruction. 1820 const MachineInstr &LastInst = Pred->back(); 1821 return !LastInst.getDesc().isBarrier(); 1822} 1823 1824 1825 1826GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) { 1827 if (!S->usesMetadata()) 1828 return 0; 1829 1830 gcp_iterator GCPI = GCMetadataPrinters.find(S); 1831 if (GCPI != GCMetadataPrinters.end()) 1832 return GCPI->second; 1833 1834 const char *Name = S->getName().c_str(); 1835 1836 for (GCMetadataPrinterRegistry::iterator 1837 I = GCMetadataPrinterRegistry::begin(), 1838 E = GCMetadataPrinterRegistry::end(); I != E; ++I) 1839 if (strcmp(Name, I->getName()) == 0) { 1840 GCMetadataPrinter *GMP = I->instantiate(); 1841 GMP->S = S; 1842 GCMetadataPrinters.insert(std::make_pair(S, GMP)); 1843 return GMP; 1844 } 1845 1846 llvm_report_error("no GCMetadataPrinter registered for GC: " + Twine(Name)); 1847 return 0; 1848} 1849 1850