1 //===-- AsmPrinter.cpp - Common AsmPrinter code ---------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements the AsmPrinter class.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/CodeGen/AsmPrinter.h"
15 #include "DwarfDebug.h"
16 #include "DwarfException.h"
17 #include "Win64Exception.h"
18 #include "WinCodeViewLineTables.h"
19 #include "llvm/ADT/SmallString.h"
20 #include "llvm/ADT/Statistic.h"
21 #include "llvm/Analysis/ConstantFolding.h"
22 #include "llvm/Analysis/JumpInstrTableInfo.h"
23 #include "llvm/CodeGen/Analysis.h"
24 #include "llvm/CodeGen/GCMetadataPrinter.h"
25 #include "llvm/CodeGen/MachineConstantPool.h"
26 #include "llvm/CodeGen/MachineFrameInfo.h"
27 #include "llvm/CodeGen/MachineFunction.h"
28 #include "llvm/CodeGen/MachineInstrBundle.h"
29 #include "llvm/CodeGen/MachineJumpTableInfo.h"
30 #include "llvm/CodeGen/MachineLoopInfo.h"
31 #include "llvm/CodeGen/MachineModuleInfo.h"
32 #include "llvm/IR/DataLayout.h"
33 #include "llvm/IR/DebugInfo.h"
34 #include "llvm/IR/Mangler.h"
35 #include "llvm/IR/Module.h"
36 #include "llvm/IR/Operator.h"
37 #include "llvm/MC/MCAsmInfo.h"
38 #include "llvm/MC/MCContext.h"
39 #include "llvm/MC/MCExpr.h"
40 #include "llvm/MC/MCInst.h"
41 #include "llvm/MC/MCSection.h"
42 #include "llvm/MC/MCStreamer.h"
43 #include "llvm/MC/MCSymbol.h"
44 #include "llvm/MC/MCValue.h"
45 #include "llvm/Support/ErrorHandling.h"
46 #include "llvm/Support/Format.h"
47 #include "llvm/Support/MathExtras.h"
48 #include "llvm/Support/TargetRegistry.h"
49 #include "llvm/Support/Timer.h"
50 #include "llvm/Target/TargetFrameLowering.h"
51 #include "llvm/Target/TargetInstrInfo.h"
52 #include "llvm/Target/TargetLowering.h"
53 #include "llvm/Target/TargetLoweringObjectFile.h"
54 #include "llvm/Target/TargetRegisterInfo.h"
55 #include "llvm/Target/TargetSubtargetInfo.h"
58 #define DEBUG_TYPE "asm-printer"
60 static const char *const DWARFGroupName = "DWARF Emission";
61 static const char *const DbgTimerName = "Debug Info Emission";
62 static const char *const EHTimerName = "DWARF Exception Writer";
63 static const char *const CodeViewLineTablesGroupName = "CodeView Line Tables";
65 STATISTIC(EmittedInsts, "Number of machine instrs printed");
67 char AsmPrinter::ID = 0;
69 typedef DenseMap<GCStrategy*, std::unique_ptr<GCMetadataPrinter>> gcp_map_type;
70 static gcp_map_type &getGCMap(void *&P) {
72 P = new gcp_map_type();
73 return *(gcp_map_type*)P;
77 /// getGVAlignmentLog2 - Return the alignment to use for the specified global
78 /// value in log2 form. This rounds up to the preferred alignment if possible
80 static unsigned getGVAlignmentLog2(const GlobalValue *GV, const DataLayout &DL,
81 unsigned InBits = 0) {
83 if (const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV))
84 NumBits = DL.getPreferredAlignmentLog(GVar);
86 // If InBits is specified, round it to it.
90 // If the GV has a specified alignment, take it into account.
91 if (GV->getAlignment() == 0)
94 unsigned GVAlign = Log2_32(GV->getAlignment());
96 // If the GVAlign is larger than NumBits, or if we are required to obey
97 // NumBits because the GV has an assigned section, obey it.
98 if (GVAlign > NumBits || GV->hasSection())
103 AsmPrinter::AsmPrinter(TargetMachine &tm, std::unique_ptr<MCStreamer> Streamer)
104 : MachineFunctionPass(ID), TM(tm), MAI(tm.getMCAsmInfo()),
105 OutContext(Streamer->getContext()), OutStreamer(*Streamer.release()),
106 LastMI(nullptr), LastFn(0), Counter(~0U), SetCounter(0) {
111 CurExceptionSym = CurrentFnSym = CurrentFnSymForSize = nullptr;
112 CurrentFnBegin = nullptr;
113 CurrentFnEnd = nullptr;
114 GCMetadataPrinters = nullptr;
115 VerboseAsm = OutStreamer.isVerboseAsm();
118 AsmPrinter::~AsmPrinter() {
119 assert(!DD && Handlers.empty() && "Debug/EH info didn't get finalized");
121 if (GCMetadataPrinters) {
122 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
125 GCMetadataPrinters = nullptr;
131 /// getFunctionNumber - Return a unique ID for the current function.
133 unsigned AsmPrinter::getFunctionNumber() const {
134 return MF->getFunctionNumber();
137 const TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
138 return *TM.getObjFileLowering();
141 /// getDataLayout - Return information about data layout.
142 const DataLayout &AsmPrinter::getDataLayout() const {
143 return *TM.getDataLayout();
146 const MCSubtargetInfo &AsmPrinter::getSubtargetInfo() const {
147 assert(MF && "getSubtargetInfo requires a valid MachineFunction!");
148 return MF->getSubtarget<MCSubtargetInfo>();
151 void AsmPrinter::EmitToStreamer(MCStreamer &S, const MCInst &Inst) {
152 S.EmitInstruction(Inst, getSubtargetInfo());
155 StringRef AsmPrinter::getTargetTriple() const {
156 return TM.getTargetTriple();
159 /// getCurrentSection() - Return the current section we are emitting to.
160 const MCSection *AsmPrinter::getCurrentSection() const {
161 return OutStreamer.getCurrentSection().first;
166 void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
167 AU.setPreservesAll();
168 MachineFunctionPass::getAnalysisUsage(AU);
169 AU.addRequired<MachineModuleInfo>();
170 AU.addRequired<GCModuleInfo>();
172 AU.addRequired<MachineLoopInfo>();
175 bool AsmPrinter::doInitialization(Module &M) {
176 MMI = getAnalysisIfAvailable<MachineModuleInfo>();
177 MMI->AnalyzeModule(M);
179 // Initialize TargetLoweringObjectFile.
180 const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
181 .Initialize(OutContext, TM);
183 OutStreamer.InitSections(false);
185 Mang = new Mangler(TM.getDataLayout());
187 // Emit the version-min deplyment target directive if needed.
189 // FIXME: If we end up with a collection of these sorts of Darwin-specific
190 // or ELF-specific things, it may make sense to have a platform helper class
191 // that will work with the target helper class. For now keep it here, as the
192 // alternative is duplicated code in each of the target asm printers that
193 // use the directive, where it would need the same conditionalization
195 Triple TT(getTargetTriple());
196 if (TT.isOSDarwin()) {
197 unsigned Major, Minor, Update;
198 TT.getOSVersion(Major, Minor, Update);
199 // If there is a version specified, Major will be non-zero.
201 OutStreamer.EmitVersionMin((TT.isMacOSX() ?
202 MCVM_OSXVersionMin : MCVM_IOSVersionMin),
203 Major, Minor, Update);
206 // Allow the target to emit any magic that it wants at the start of the file.
207 EmitStartOfAsmFile(M);
209 // Very minimal debug info. It is ignored if we emit actual debug info. If we
210 // don't, this at least helps the user find where a global came from.
211 if (MAI->hasSingleParameterDotFile()) {
213 OutStreamer.EmitFileDirective(M.getModuleIdentifier());
216 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
217 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
219 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
220 MP->beginAssembly(M, *MI, *this);
222 // Emit module-level inline asm if it exists.
223 if (!M.getModuleInlineAsm().empty()) {
224 // We're at the module level. Construct MCSubtarget from the default CPU
225 // and target triple.
226 std::unique_ptr<MCSubtargetInfo> STI(TM.getTarget().createMCSubtargetInfo(
227 TM.getTargetTriple(), TM.getTargetCPU(), TM.getTargetFeatureString()));
228 OutStreamer.AddComment("Start of file scope inline assembly");
229 OutStreamer.AddBlankLine();
230 EmitInlineAsm(M.getModuleInlineAsm()+"\n", *STI);
231 OutStreamer.AddComment("End of file scope inline assembly");
232 OutStreamer.AddBlankLine();
235 if (MAI->doesSupportDebugInformation()) {
236 bool skip_dwarf = false;
237 if (Triple(TM.getTargetTriple()).isKnownWindowsMSVCEnvironment()) {
238 Handlers.push_back(HandlerInfo(new WinCodeViewLineTables(this),
240 CodeViewLineTablesGroupName));
241 // FIXME: Don't emit DWARF debug info if there's at least one function
242 // with AddressSanitizer instrumentation.
243 // This is a band-aid fix for PR22032.
244 for (auto &F : M.functions()) {
245 if (F.hasFnAttribute(Attribute::SanitizeAddress)) {
252 DD = new DwarfDebug(this, &M);
253 Handlers.push_back(HandlerInfo(DD, DbgTimerName, DWARFGroupName));
257 EHStreamer *ES = nullptr;
258 switch (MAI->getExceptionHandlingType()) {
259 case ExceptionHandling::None:
261 case ExceptionHandling::SjLj:
262 case ExceptionHandling::DwarfCFI:
263 ES = new DwarfCFIException(this);
265 case ExceptionHandling::ARM:
266 ES = new ARMException(this);
268 case ExceptionHandling::WinEH:
269 switch (MAI->getWinEHEncodingType()) {
270 default: llvm_unreachable("unsupported unwinding information encoding");
271 case WinEH::EncodingType::Itanium:
272 ES = new Win64Exception(this);
278 Handlers.push_back(HandlerInfo(ES, EHTimerName, DWARFGroupName));
282 static bool canBeHidden(const GlobalValue *GV, const MCAsmInfo &MAI) {
283 if (!MAI.hasWeakDefCanBeHiddenDirective())
286 return canBeOmittedFromSymbolTable(GV);
289 void AsmPrinter::EmitLinkage(const GlobalValue *GV, MCSymbol *GVSym) const {
290 GlobalValue::LinkageTypes Linkage = GV->getLinkage();
292 case GlobalValue::CommonLinkage:
293 case GlobalValue::LinkOnceAnyLinkage:
294 case GlobalValue::LinkOnceODRLinkage:
295 case GlobalValue::WeakAnyLinkage:
296 case GlobalValue::WeakODRLinkage:
297 if (MAI->hasWeakDefDirective()) {
299 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
301 if (!canBeHidden(GV, *MAI))
302 // .weak_definition _foo
303 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition);
305 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefAutoPrivate);
306 } else if (MAI->hasLinkOnceDirective()) {
308 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
309 //NOTE: linkonce is handled by the section the symbol was assigned to.
312 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak);
315 case GlobalValue::AppendingLinkage:
316 // FIXME: appending linkage variables should go into a section of
317 // their name or something. For now, just emit them as external.
318 case GlobalValue::ExternalLinkage:
319 // If external or appending, declare as a global symbol.
321 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
323 case GlobalValue::PrivateLinkage:
324 case GlobalValue::InternalLinkage:
326 case GlobalValue::AvailableExternallyLinkage:
327 llvm_unreachable("Should never emit this");
328 case GlobalValue::ExternalWeakLinkage:
329 llvm_unreachable("Don't know how to emit these");
331 llvm_unreachable("Unknown linkage type!");
334 void AsmPrinter::getNameWithPrefix(SmallVectorImpl<char> &Name,
335 const GlobalValue *GV) const {
336 TM.getNameWithPrefix(Name, GV, *Mang);
339 MCSymbol *AsmPrinter::getSymbol(const GlobalValue *GV) const {
340 return TM.getSymbol(GV, *Mang);
343 /// EmitGlobalVariable - Emit the specified global variable to the .s file.
344 void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
345 if (GV->hasInitializer()) {
346 // Check to see if this is a special global used by LLVM, if so, emit it.
347 if (EmitSpecialLLVMGlobal(GV))
350 // Skip the emission of global equivalents. The symbol can be emitted later
351 // on by emitGlobalGOTEquivs in case it turns out to be needed.
352 if (GlobalGOTEquivs.count(getSymbol(GV)))
356 GV->printAsOperand(OutStreamer.GetCommentOS(),
357 /*PrintType=*/false, GV->getParent());
358 OutStreamer.GetCommentOS() << '\n';
362 MCSymbol *GVSym = getSymbol(GV);
363 EmitVisibility(GVSym, GV->getVisibility(), !GV->isDeclaration());
365 if (!GV->hasInitializer()) // External globals require no extra code.
368 GVSym->redefineIfPossible();
369 if (GVSym->isDefined() || GVSym->isVariable())
370 report_fatal_error("symbol '" + Twine(GVSym->getName()) +
371 "' is already defined");
373 if (MAI->hasDotTypeDotSizeDirective())
374 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
376 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
378 const DataLayout *DL = TM.getDataLayout();
379 uint64_t Size = DL->getTypeAllocSize(GV->getType()->getElementType());
381 // If the alignment is specified, we *must* obey it. Overaligning a global
382 // with a specified alignment is a prompt way to break globals emitted to
383 // sections and expected to be contiguous (e.g. ObjC metadata).
384 unsigned AlignLog = getGVAlignmentLog2(GV, *DL);
386 for (const HandlerInfo &HI : Handlers) {
387 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled);
388 HI.Handler->setSymbolSize(GVSym, Size);
391 // Handle common and BSS local symbols (.lcomm).
392 if (GVKind.isCommon() || GVKind.isBSSLocal()) {
393 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
394 unsigned Align = 1 << AlignLog;
396 // Handle common symbols.
397 if (GVKind.isCommon()) {
398 if (!getObjFileLowering().getCommDirectiveSupportsAlignment())
402 OutStreamer.EmitCommonSymbol(GVSym, Size, Align);
406 // Handle local BSS symbols.
407 if (MAI->hasMachoZeroFillDirective()) {
408 const MCSection *TheSection =
409 getObjFileLowering().SectionForGlobal(GV, GVKind, *Mang, TM);
410 // .zerofill __DATA, __bss, _foo, 400, 5
411 OutStreamer.EmitZerofill(TheSection, GVSym, Size, Align);
415 // Use .lcomm only if it supports user-specified alignment.
416 // Otherwise, while it would still be correct to use .lcomm in some
417 // cases (e.g. when Align == 1), the external assembler might enfore
418 // some -unknown- default alignment behavior, which could cause
419 // spurious differences between external and integrated assembler.
420 // Prefer to simply fall back to .local / .comm in this case.
421 if (MAI->getLCOMMDirectiveAlignmentType() != LCOMM::NoAlignment) {
423 OutStreamer.EmitLocalCommonSymbol(GVSym, Size, Align);
427 if (!getObjFileLowering().getCommDirectiveSupportsAlignment())
431 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local);
433 OutStreamer.EmitCommonSymbol(GVSym, Size, Align);
437 const MCSection *TheSection =
438 getObjFileLowering().SectionForGlobal(GV, GVKind, *Mang, TM);
440 // Handle the zerofill directive on darwin, which is a special form of BSS
442 if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) {
443 if (Size == 0) Size = 1; // zerofill of 0 bytes is undefined.
446 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
447 // .zerofill __DATA, __common, _foo, 400, 5
448 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
452 // Handle thread local data for mach-o which requires us to output an
453 // additional structure of data and mangle the original symbol so that we
454 // can reference it later.
456 // TODO: This should become an "emit thread local global" method on TLOF.
457 // All of this macho specific stuff should be sunk down into TLOFMachO and
458 // stuff like "TLSExtraDataSection" should no longer be part of the parent
459 // TLOF class. This will also make it more obvious that stuff like
460 // MCStreamer::EmitTBSSSymbol is macho specific and only called from macho
462 if (GVKind.isThreadLocal() && MAI->hasMachoTBSSDirective()) {
463 // Emit the .tbss symbol
465 OutContext.GetOrCreateSymbol(GVSym->getName() + Twine("$tlv$init"));
467 if (GVKind.isThreadBSS()) {
468 TheSection = getObjFileLowering().getTLSBSSSection();
469 OutStreamer.EmitTBSSSymbol(TheSection, MangSym, Size, 1 << AlignLog);
470 } else if (GVKind.isThreadData()) {
471 OutStreamer.SwitchSection(TheSection);
473 EmitAlignment(AlignLog, GV);
474 OutStreamer.EmitLabel(MangSym);
476 EmitGlobalConstant(GV->getInitializer());
479 OutStreamer.AddBlankLine();
481 // Emit the variable struct for the runtime.
482 const MCSection *TLVSect
483 = getObjFileLowering().getTLSExtraDataSection();
485 OutStreamer.SwitchSection(TLVSect);
486 // Emit the linkage here.
487 EmitLinkage(GV, GVSym);
488 OutStreamer.EmitLabel(GVSym);
490 // Three pointers in size:
491 // - __tlv_bootstrap - used to make sure support exists
492 // - spare pointer, used when mapped by the runtime
493 // - pointer to mangled symbol above with initializer
494 unsigned PtrSize = DL->getPointerTypeSize(GV->getType());
495 OutStreamer.EmitSymbolValue(GetExternalSymbolSymbol("_tlv_bootstrap"),
497 OutStreamer.EmitIntValue(0, PtrSize);
498 OutStreamer.EmitSymbolValue(MangSym, PtrSize);
500 OutStreamer.AddBlankLine();
504 OutStreamer.SwitchSection(TheSection);
506 EmitLinkage(GV, GVSym);
507 EmitAlignment(AlignLog, GV);
509 OutStreamer.EmitLabel(GVSym);
511 EmitGlobalConstant(GV->getInitializer());
513 if (MAI->hasDotTypeDotSizeDirective())
515 OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext));
517 OutStreamer.AddBlankLine();
520 /// EmitFunctionHeader - This method emits the header for the current
522 void AsmPrinter::EmitFunctionHeader() {
523 // Print out constants referenced by the function
526 // Print the 'header' of function.
527 const Function *F = MF->getFunction();
529 OutStreamer.SwitchSection(
530 getObjFileLowering().SectionForGlobal(F, *Mang, TM));
531 EmitVisibility(CurrentFnSym, F->getVisibility());
533 EmitLinkage(F, CurrentFnSym);
534 if (MAI->hasFunctionAlignment())
535 EmitAlignment(MF->getAlignment(), F);
537 if (MAI->hasDotTypeDotSizeDirective())
538 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
541 F->printAsOperand(OutStreamer.GetCommentOS(),
542 /*PrintType=*/false, F->getParent());
543 OutStreamer.GetCommentOS() << '\n';
546 // Emit the prefix data.
547 if (F->hasPrefixData())
548 EmitGlobalConstant(F->getPrefixData());
550 // Emit the CurrentFnSym. This is a virtual function to allow targets to
551 // do their wild and crazy things as required.
552 EmitFunctionEntryLabel();
554 // If the function had address-taken blocks that got deleted, then we have
555 // references to the dangling symbols. Emit them at the start of the function
556 // so that we don't get references to undefined symbols.
557 std::vector<MCSymbol*> DeadBlockSyms;
558 MMI->takeDeletedSymbolsForFunction(F, DeadBlockSyms);
559 for (unsigned i = 0, e = DeadBlockSyms.size(); i != e; ++i) {
560 OutStreamer.AddComment("Address taken block that was later removed");
561 OutStreamer.EmitLabel(DeadBlockSyms[i]);
564 if (CurrentFnBegin) {
565 if (MAI->useAssignmentForEHBegin()) {
566 MCSymbol *CurPos = OutContext.CreateTempSymbol();
567 OutStreamer.EmitLabel(CurPos);
568 OutStreamer.EmitAssignment(CurrentFnBegin,
569 MCSymbolRefExpr::Create(CurPos, OutContext));
571 OutStreamer.EmitLabel(CurrentFnBegin);
575 // Emit pre-function debug and/or EH information.
576 for (const HandlerInfo &HI : Handlers) {
577 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled);
578 HI.Handler->beginFunction(MF);
581 // Emit the prologue data.
582 if (F->hasPrologueData())
583 EmitGlobalConstant(F->getPrologueData());
586 /// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
587 /// function. This can be overridden by targets as required to do custom stuff.
588 void AsmPrinter::EmitFunctionEntryLabel() {
589 CurrentFnSym->redefineIfPossible();
591 // The function label could have already been emitted if two symbols end up
592 // conflicting due to asm renaming. Detect this and emit an error.
593 if (CurrentFnSym->isVariable())
594 report_fatal_error("'" + Twine(CurrentFnSym->getName()) +
595 "' is a protected alias");
596 if (CurrentFnSym->isDefined())
597 report_fatal_error("'" + Twine(CurrentFnSym->getName()) +
598 "' label emitted multiple times to assembly file");
600 return OutStreamer.EmitLabel(CurrentFnSym);
603 /// emitComments - Pretty-print comments for instructions.
604 static void emitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
605 const MachineFunction *MF = MI.getParent()->getParent();
606 const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
608 // Check for spills and reloads
611 const MachineFrameInfo *FrameInfo = MF->getFrameInfo();
613 // We assume a single instruction only has a spill or reload, not
615 const MachineMemOperand *MMO;
616 if (TII->isLoadFromStackSlotPostFE(&MI, FI)) {
617 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
618 MMO = *MI.memoperands_begin();
619 CommentOS << MMO->getSize() << "-byte Reload\n";
621 } else if (TII->hasLoadFromStackSlot(&MI, MMO, FI)) {
622 if (FrameInfo->isSpillSlotObjectIndex(FI))
623 CommentOS << MMO->getSize() << "-byte Folded Reload\n";
624 } else if (TII->isStoreToStackSlotPostFE(&MI, FI)) {
625 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
626 MMO = *MI.memoperands_begin();
627 CommentOS << MMO->getSize() << "-byte Spill\n";
629 } else if (TII->hasStoreToStackSlot(&MI, MMO, FI)) {
630 if (FrameInfo->isSpillSlotObjectIndex(FI))
631 CommentOS << MMO->getSize() << "-byte Folded Spill\n";
634 // Check for spill-induced copies
635 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse))
636 CommentOS << " Reload Reuse\n";
639 /// emitImplicitDef - This method emits the specified machine instruction
640 /// that is an implicit def.
641 void AsmPrinter::emitImplicitDef(const MachineInstr *MI) const {
642 unsigned RegNo = MI->getOperand(0).getReg();
643 OutStreamer.AddComment(Twine("implicit-def: ") +
644 MMI->getContext().getRegisterInfo()->getName(RegNo));
645 OutStreamer.AddBlankLine();
648 static void emitKill(const MachineInstr *MI, AsmPrinter &AP) {
649 std::string Str = "kill:";
650 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
651 const MachineOperand &Op = MI->getOperand(i);
652 assert(Op.isReg() && "KILL instruction must have only register operands");
654 Str += AP.MMI->getContext().getRegisterInfo()->getName(Op.getReg());
655 Str += (Op.isDef() ? "<def>" : "<kill>");
657 AP.OutStreamer.AddComment(Str);
658 AP.OutStreamer.AddBlankLine();
661 /// emitDebugValueComment - This method handles the target-independent form
662 /// of DBG_VALUE, returning true if it was able to do so. A false return
663 /// means the target will need to handle MI in EmitInstruction.
664 static bool emitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) {
665 // This code handles only the 4-operand target-independent form.
666 if (MI->getNumOperands() != 4)
669 SmallString<128> Str;
670 raw_svector_ostream OS(Str);
671 OS << "DEBUG_VALUE: ";
673 DIVariable V = MI->getDebugVariable();
674 if (V.getContext().isSubprogram()) {
675 StringRef Name = DISubprogram(V.getContext()).getDisplayName();
681 DIExpression Expr = MI->getDebugExpression();
682 if (Expr.isBitPiece())
683 OS << " [bit_piece offset=" << Expr.getBitPieceOffset()
684 << " size=" << Expr.getBitPieceSize() << "]";
687 // The second operand is only an offset if it's an immediate.
688 bool Deref = MI->getOperand(0).isReg() && MI->getOperand(1).isImm();
689 int64_t Offset = Deref ? MI->getOperand(1).getImm() : 0;
691 // Register or immediate value. Register 0 means undef.
692 if (MI->getOperand(0).isFPImm()) {
693 APFloat APF = APFloat(MI->getOperand(0).getFPImm()->getValueAPF());
694 if (MI->getOperand(0).getFPImm()->getType()->isFloatTy()) {
695 OS << (double)APF.convertToFloat();
696 } else if (MI->getOperand(0).getFPImm()->getType()->isDoubleTy()) {
697 OS << APF.convertToDouble();
699 // There is no good way to print long double. Convert a copy to
700 // double. Ah well, it's only a comment.
702 APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
704 OS << "(long double) " << APF.convertToDouble();
706 } else if (MI->getOperand(0).isImm()) {
707 OS << MI->getOperand(0).getImm();
708 } else if (MI->getOperand(0).isCImm()) {
709 MI->getOperand(0).getCImm()->getValue().print(OS, false /*isSigned*/);
712 if (MI->getOperand(0).isReg()) {
713 Reg = MI->getOperand(0).getReg();
715 assert(MI->getOperand(0).isFI() && "Unknown operand type");
716 const TargetFrameLowering *TFI = AP.MF->getSubtarget().getFrameLowering();
717 Offset += TFI->getFrameIndexReference(*AP.MF,
718 MI->getOperand(0).getIndex(), Reg);
722 // Suppress offset, it is not meaningful here.
724 // NOTE: Want this comment at start of line, don't emit with AddComment.
725 AP.OutStreamer.emitRawComment(OS.str());
730 OS << AP.MMI->getContext().getRegisterInfo()->getName(Reg);
734 OS << '+' << Offset << ']';
736 // NOTE: Want this comment at start of line, don't emit with AddComment.
737 AP.OutStreamer.emitRawComment(OS.str());
741 AsmPrinter::CFIMoveType AsmPrinter::needsCFIMoves() {
742 if (MAI->getExceptionHandlingType() == ExceptionHandling::DwarfCFI &&
743 MF->getFunction()->needsUnwindTableEntry())
746 if (MMI->hasDebugInfo())
752 bool AsmPrinter::needsSEHMoves() {
753 return MAI->usesWindowsCFI() && MF->getFunction()->needsUnwindTableEntry();
756 void AsmPrinter::emitCFIInstruction(const MachineInstr &MI) {
757 ExceptionHandling ExceptionHandlingType = MAI->getExceptionHandlingType();
758 if (ExceptionHandlingType != ExceptionHandling::DwarfCFI &&
759 ExceptionHandlingType != ExceptionHandling::ARM)
762 if (needsCFIMoves() == CFI_M_None)
765 const MachineModuleInfo &MMI = MF->getMMI();
766 const std::vector<MCCFIInstruction> &Instrs = MMI.getFrameInstructions();
767 unsigned CFIIndex = MI.getOperand(0).getCFIIndex();
768 const MCCFIInstruction &CFI = Instrs[CFIIndex];
769 emitCFIInstruction(CFI);
772 void AsmPrinter::emitFrameAlloc(const MachineInstr &MI) {
773 // The operands are the MCSymbol and the frame offset of the allocation.
774 MCSymbol *FrameAllocSym = MI.getOperand(0).getMCSymbol();
775 int FrameOffset = MI.getOperand(1).getImm();
777 // Emit a symbol assignment.
778 OutStreamer.EmitAssignment(FrameAllocSym,
779 MCConstantExpr::Create(FrameOffset, OutContext));
782 /// EmitFunctionBody - This method emits the body and trailer for a
784 void AsmPrinter::EmitFunctionBody() {
785 // Emit target-specific gunk before the function body.
786 EmitFunctionBodyStart();
788 bool ShouldPrintDebugScopes = MMI->hasDebugInfo();
790 // Print out code for the function.
791 bool HasAnyRealCode = false;
792 for (auto &MBB : *MF) {
793 // Print a label for the basic block.
794 EmitBasicBlockStart(MBB);
795 for (auto &MI : MBB) {
797 // Print the assembly for the instruction.
798 if (!MI.isPosition() && !MI.isImplicitDef() && !MI.isKill() &&
799 !MI.isDebugValue()) {
800 HasAnyRealCode = true;
804 if (ShouldPrintDebugScopes) {
805 for (const HandlerInfo &HI : Handlers) {
806 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName,
807 TimePassesIsEnabled);
808 HI.Handler->beginInstruction(&MI);
813 emitComments(MI, OutStreamer.GetCommentOS());
815 switch (MI.getOpcode()) {
816 case TargetOpcode::CFI_INSTRUCTION:
817 emitCFIInstruction(MI);
820 case TargetOpcode::FRAME_ALLOC:
824 case TargetOpcode::EH_LABEL:
825 case TargetOpcode::GC_LABEL:
826 OutStreamer.EmitLabel(MI.getOperand(0).getMCSymbol());
828 case TargetOpcode::INLINEASM:
831 case TargetOpcode::DBG_VALUE:
833 if (!emitDebugValueComment(&MI, *this))
834 EmitInstruction(&MI);
837 case TargetOpcode::IMPLICIT_DEF:
838 if (isVerbose()) emitImplicitDef(&MI);
840 case TargetOpcode::KILL:
841 if (isVerbose()) emitKill(&MI, *this);
844 EmitInstruction(&MI);
848 if (ShouldPrintDebugScopes) {
849 for (const HandlerInfo &HI : Handlers) {
850 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName,
851 TimePassesIsEnabled);
852 HI.Handler->endInstruction();
857 EmitBasicBlockEnd(MBB);
860 // If the function is empty and the object file uses .subsections_via_symbols,
861 // then we need to emit *something* to the function body to prevent the
862 // labels from collapsing together. Just emit a noop.
863 if ((MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode)) {
865 MF->getSubtarget().getInstrInfo()->getNoopForMachoTarget(Noop);
866 OutStreamer.AddComment("avoids zero-length function");
868 // Targets can opt-out of emitting the noop here by leaving the opcode
870 if (Noop.getOpcode())
871 OutStreamer.EmitInstruction(Noop, getSubtargetInfo());
874 const Function *F = MF->getFunction();
875 for (const auto &BB : *F) {
876 if (!BB.hasAddressTaken())
878 MCSymbol *Sym = GetBlockAddressSymbol(&BB);
879 if (Sym->isDefined())
881 OutStreamer.AddComment("Address of block that was removed by CodeGen");
882 OutStreamer.EmitLabel(Sym);
885 // Emit target-specific gunk after the function body.
886 EmitFunctionBodyEnd();
888 if (!MMI->getLandingPads().empty() || MMI->hasDebugInfo() ||
889 MAI->hasDotTypeDotSizeDirective()) {
890 // Create a symbol for the end of function.
891 CurrentFnEnd = createTempSymbol("func_end", getFunctionNumber());
892 OutStreamer.EmitLabel(CurrentFnEnd);
895 // If the target wants a .size directive for the size of the function, emit
897 if (MAI->hasDotTypeDotSizeDirective()) {
898 // We can get the size as difference between the function label and the
900 const MCExpr *SizeExp =
901 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(CurrentFnEnd, OutContext),
902 MCSymbolRefExpr::Create(CurrentFnSymForSize,
905 OutStreamer.EmitELFSize(CurrentFnSym, SizeExp);
908 for (const HandlerInfo &HI : Handlers) {
909 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled);
910 HI.Handler->markFunctionEnd();
913 // Print out jump tables referenced by the function.
916 // Emit post-function debug and/or EH information.
917 for (const HandlerInfo &HI : Handlers) {
918 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled);
919 HI.Handler->endFunction(MF);
923 OutStreamer.AddBlankLine();
926 /// \brief Compute the number of Global Variables that uses a Constant.
927 static unsigned getNumGlobalVariableUses(const Constant *C) {
931 if (isa<GlobalVariable>(C))
934 unsigned NumUses = 0;
935 for (auto *CU : C->users())
936 NumUses += getNumGlobalVariableUses(dyn_cast<Constant>(CU));
941 /// \brief Only consider global GOT equivalents if at least one user is a
942 /// cstexpr inside an initializer of another global variables. Also, don't
943 /// handle cstexpr inside instructions. During global variable emission,
944 /// candidates are skipped and are emitted later in case at least one cstexpr
945 /// isn't replaced by a PC relative GOT entry access.
946 static bool isGOTEquivalentCandidate(const GlobalVariable *GV,
947 unsigned &NumGOTEquivUsers) {
948 // Global GOT equivalents are unnamed private globals with a constant
949 // pointer initializer to another global symbol. They must point to a
950 // GlobalVariable or Function, i.e., as GlobalValue.
951 if (!GV->hasUnnamedAddr() || !GV->hasInitializer() || !GV->isConstant() ||
952 !GV->isDiscardableIfUnused() || !dyn_cast<GlobalValue>(GV->getOperand(0)))
955 // To be a got equivalent, at least one of its users need to be a constant
956 // expression used by another global variable.
957 for (auto *U : GV->users())
958 NumGOTEquivUsers += getNumGlobalVariableUses(cast<Constant>(U));
960 return NumGOTEquivUsers > 0;
963 /// \brief Unnamed constant global variables solely contaning a pointer to
964 /// another globals variable is equivalent to a GOT table entry; it contains the
965 /// the address of another symbol. Optimize it and replace accesses to these
966 /// "GOT equivalents" by using the GOT entry for the final global instead.
967 /// Compute GOT equivalent candidates among all global variables to avoid
968 /// emitting them if possible later on, after it use is replaced by a GOT entry
970 void AsmPrinter::computeGlobalGOTEquivs(Module &M) {
971 if (!getObjFileLowering().supportIndirectSymViaGOTPCRel())
974 for (const auto &G : M.globals()) {
975 unsigned NumGOTEquivUsers = 0;
976 if (!isGOTEquivalentCandidate(&G, NumGOTEquivUsers))
979 const MCSymbol *GOTEquivSym = getSymbol(&G);
980 GlobalGOTEquivs[GOTEquivSym] = std::make_pair(&G, NumGOTEquivUsers);
984 /// \brief Constant expressions using GOT equivalent globals may not be eligible
985 /// for PC relative GOT entry conversion, in such cases we need to emit such
986 /// globals we previously omitted in EmitGlobalVariable.
987 void AsmPrinter::emitGlobalGOTEquivs() {
988 if (!getObjFileLowering().supportIndirectSymViaGOTPCRel())
991 SmallVector<const GlobalVariable *, 8> FailedCandidates;
992 for (auto &I : GlobalGOTEquivs) {
993 const GlobalVariable *GV = I.second.first;
994 unsigned Cnt = I.second.second;
996 FailedCandidates.push_back(GV);
998 GlobalGOTEquivs.clear();
1000 for (auto *GV : FailedCandidates)
1001 EmitGlobalVariable(GV);
1004 bool AsmPrinter::doFinalization(Module &M) {
1005 // Gather all GOT equivalent globals in the module. We really need two
1006 // passes over the globals: one to compute and another to avoid its emission
1007 // in EmitGlobalVariable, otherwise we would not be able to handle cases
1008 // where the got equivalent shows up before its use.
1009 computeGlobalGOTEquivs(M);
1011 // Emit global variables.
1012 for (const auto &G : M.globals())
1013 EmitGlobalVariable(&G);
1015 // Emit remaining GOT equivalent globals.
1016 emitGlobalGOTEquivs();
1018 // Emit visibility info for declarations
1019 for (const Function &F : M) {
1020 if (!F.isDeclaration())
1022 GlobalValue::VisibilityTypes V = F.getVisibility();
1023 if (V == GlobalValue::DefaultVisibility)
1026 MCSymbol *Name = getSymbol(&F);
1027 EmitVisibility(Name, V, false);
1030 // Emit module flags.
1031 SmallVector<Module::ModuleFlagEntry, 8> ModuleFlags;
1032 M.getModuleFlagsMetadata(ModuleFlags);
1033 if (!ModuleFlags.empty())
1034 getObjFileLowering().emitModuleFlags(OutStreamer, ModuleFlags, *Mang, TM);
1036 // Make sure we wrote out everything we need.
1037 OutStreamer.Flush();
1039 // Finalize debug and EH information.
1040 for (const HandlerInfo &HI : Handlers) {
1041 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName,
1042 TimePassesIsEnabled);
1043 HI.Handler->endModule();
1049 // If the target wants to know about weak references, print them all.
1050 if (MAI->getWeakRefDirective()) {
1051 // FIXME: This is not lazy, it would be nice to only print weak references
1052 // to stuff that is actually used. Note that doing so would require targets
1053 // to notice uses in operands (due to constant exprs etc). This should
1054 // happen with the MC stuff eventually.
1056 // Print out module-level global variables here.
1057 for (const auto &G : M.globals()) {
1058 if (!G.hasExternalWeakLinkage())
1060 OutStreamer.EmitSymbolAttribute(getSymbol(&G), MCSA_WeakReference);
1063 for (const auto &F : M) {
1064 if (!F.hasExternalWeakLinkage())
1066 OutStreamer.EmitSymbolAttribute(getSymbol(&F), MCSA_WeakReference);
1070 OutStreamer.AddBlankLine();
1071 for (const auto &Alias : M.aliases()) {
1072 MCSymbol *Name = getSymbol(&Alias);
1074 if (Alias.hasExternalLinkage() || !MAI->getWeakRefDirective())
1075 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
1076 else if (Alias.hasWeakLinkage() || Alias.hasLinkOnceLinkage())
1077 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
1079 assert(Alias.hasLocalLinkage() && "Invalid alias linkage");
1081 EmitVisibility(Name, Alias.getVisibility());
1083 // Emit the directives as assignments aka .set:
1084 OutStreamer.EmitAssignment(Name, lowerConstant(Alias.getAliasee()));
1087 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
1088 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
1089 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
1090 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(**--I))
1091 MP->finishAssembly(M, *MI, *this);
1093 // Emit llvm.ident metadata in an '.ident' directive.
1094 EmitModuleIdents(M);
1096 // Emit __morestack address if needed for indirect calls.
1097 if (MMI->usesMorestackAddr()) {
1098 const MCSection *ReadOnlySection =
1099 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly(),
1101 OutStreamer.SwitchSection(ReadOnlySection);
1103 MCSymbol *AddrSymbol =
1104 OutContext.GetOrCreateSymbol(StringRef("__morestack_addr"));
1105 OutStreamer.EmitLabel(AddrSymbol);
1107 unsigned PtrSize = TM.getDataLayout()->getPointerSize(0);
1108 OutStreamer.EmitSymbolValue(GetExternalSymbolSymbol("__morestack"),
1112 // If we don't have any trampolines, then we don't require stack memory
1113 // to be executable. Some targets have a directive to declare this.
1114 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
1115 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
1116 if (const MCSection *S = MAI->getNonexecutableStackSection(OutContext))
1117 OutStreamer.SwitchSection(S);
1119 // Allow the target to emit any magic that it wants at the end of the file,
1120 // after everything else has gone out.
1121 EmitEndOfAsmFile(M);
1123 delete Mang; Mang = nullptr;
1126 OutStreamer.Finish();
1127 OutStreamer.reset();
1132 MCSymbol *AsmPrinter::getCurExceptionSym() {
1133 if (!CurExceptionSym)
1134 CurExceptionSym = createTempSymbol("exception", getFunctionNumber());
1135 return CurExceptionSym;
1138 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
1140 // Get the function symbol.
1141 CurrentFnSym = getSymbol(MF.getFunction());
1142 CurrentFnSymForSize = CurrentFnSym;
1143 CurrentFnBegin = nullptr;
1144 CurExceptionSym = nullptr;
1145 bool NeedsLocalForSize = MAI->needsLocalForSize();
1146 if (!MMI->getLandingPads().empty() || MMI->hasDebugInfo() ||
1147 NeedsLocalForSize) {
1148 CurrentFnBegin = createTempSymbol("func_begin", getFunctionNumber());
1149 if (NeedsLocalForSize)
1150 CurrentFnSymForSize = CurrentFnBegin;
1154 LI = &getAnalysis<MachineLoopInfo>();
1158 // SectionCPs - Keep track the alignment, constpool entries per Section.
1162 SmallVector<unsigned, 4> CPEs;
1163 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
1167 /// EmitConstantPool - Print to the current output stream assembly
1168 /// representations of the constants in the constant pool MCP. This is
1169 /// used to print out constants which have been "spilled to memory" by
1170 /// the code generator.
1172 void AsmPrinter::EmitConstantPool() {
1173 const MachineConstantPool *MCP = MF->getConstantPool();
1174 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
1175 if (CP.empty()) return;
1177 // Calculate sections for constant pool entries. We collect entries to go into
1178 // the same section together to reduce amount of section switch statements.
1179 SmallVector<SectionCPs, 4> CPSections;
1180 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
1181 const MachineConstantPoolEntry &CPE = CP[i];
1182 unsigned Align = CPE.getAlignment();
1185 CPE.getSectionKind(TM.getDataLayout());
1187 const Constant *C = nullptr;
1188 if (!CPE.isMachineConstantPoolEntry())
1189 C = CPE.Val.ConstVal;
1191 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind, C);
1193 // The number of sections are small, just do a linear search from the
1194 // last section to the first.
1196 unsigned SecIdx = CPSections.size();
1197 while (SecIdx != 0) {
1198 if (CPSections[--SecIdx].S == S) {
1204 SecIdx = CPSections.size();
1205 CPSections.push_back(SectionCPs(S, Align));
1208 if (Align > CPSections[SecIdx].Alignment)
1209 CPSections[SecIdx].Alignment = Align;
1210 CPSections[SecIdx].CPEs.push_back(i);
1213 // Now print stuff into the calculated sections.
1214 const MCSection *CurSection = nullptr;
1215 unsigned Offset = 0;
1216 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
1217 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
1218 unsigned CPI = CPSections[i].CPEs[j];
1219 MCSymbol *Sym = GetCPISymbol(CPI);
1220 if (!Sym->isUndefined())
1223 if (CurSection != CPSections[i].S) {
1224 OutStreamer.SwitchSection(CPSections[i].S);
1225 EmitAlignment(Log2_32(CPSections[i].Alignment));
1226 CurSection = CPSections[i].S;
1230 MachineConstantPoolEntry CPE = CP[CPI];
1232 // Emit inter-object padding for alignment.
1233 unsigned AlignMask = CPE.getAlignment() - 1;
1234 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
1235 OutStreamer.EmitZeros(NewOffset - Offset);
1237 Type *Ty = CPE.getType();
1238 Offset = NewOffset +
1239 TM.getDataLayout()->getTypeAllocSize(Ty);
1241 OutStreamer.EmitLabel(Sym);
1242 if (CPE.isMachineConstantPoolEntry())
1243 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
1245 EmitGlobalConstant(CPE.Val.ConstVal);
1250 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
1251 /// by the current function to the current output stream.
1253 void AsmPrinter::EmitJumpTableInfo() {
1254 const DataLayout *DL = MF->getTarget().getDataLayout();
1255 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
1257 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
1258 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
1259 if (JT.empty()) return;
1261 // Pick the directive to use to print the jump table entries, and switch to
1262 // the appropriate section.
1263 const Function *F = MF->getFunction();
1264 const TargetLoweringObjectFile &TLOF = getObjFileLowering();
1265 bool JTInDiffSection = !TLOF.shouldPutJumpTableInFunctionSection(
1266 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32,
1268 if (JTInDiffSection) {
1269 // Drop it in the readonly section.
1270 const MCSection *ReadOnlySection =
1271 TLOF.getSectionForJumpTable(*F, *Mang, TM);
1272 OutStreamer.SwitchSection(ReadOnlySection);
1275 EmitAlignment(Log2_32(
1276 MJTI->getEntryAlignment(*TM.getDataLayout())));
1278 // Jump tables in code sections are marked with a data_region directive
1279 // where that's supported.
1280 if (!JTInDiffSection)
1281 OutStreamer.EmitDataRegion(MCDR_DataRegionJT32);
1283 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
1284 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
1286 // If this jump table was deleted, ignore it.
1287 if (JTBBs.empty()) continue;
1289 // For the EK_LabelDifference32 entry, if using .set avoids a relocation,
1290 /// emit a .set directive for each unique entry.
1291 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
1292 MAI->doesSetDirectiveSuppressesReloc()) {
1293 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
1294 const TargetLowering *TLI = MF->getSubtarget().getTargetLowering();
1295 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
1296 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
1297 const MachineBasicBlock *MBB = JTBBs[ii];
1298 if (!EmittedSets.insert(MBB).second)
1301 // .set LJTSet, LBB32-base
1303 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1304 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
1305 MCBinaryExpr::CreateSub(LHS, Base, OutContext));
1309 // On some targets (e.g. Darwin) we want to emit two consecutive labels
1310 // before each jump table. The first label is never referenced, but tells
1311 // the assembler and linker the extents of the jump table object. The
1312 // second label is actually referenced by the code.
1313 if (JTInDiffSection && DL->hasLinkerPrivateGlobalPrefix())
1314 // FIXME: This doesn't have to have any specific name, just any randomly
1315 // named and numbered 'l' label would work. Simplify GetJTISymbol.
1316 OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
1318 OutStreamer.EmitLabel(GetJTISymbol(JTI));
1320 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
1321 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
1323 if (!JTInDiffSection)
1324 OutStreamer.EmitDataRegion(MCDR_DataRegionEnd);
1327 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
1329 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
1330 const MachineBasicBlock *MBB,
1331 unsigned UID) const {
1332 assert(MBB && MBB->getNumber() >= 0 && "Invalid basic block");
1333 const MCExpr *Value = nullptr;
1334 switch (MJTI->getEntryKind()) {
1335 case MachineJumpTableInfo::EK_Inline:
1336 llvm_unreachable("Cannot emit EK_Inline jump table entry");
1337 case MachineJumpTableInfo::EK_Custom32:
1338 Value = MF->getSubtarget().getTargetLowering()->LowerCustomJumpTableEntry(
1339 MJTI, MBB, UID, OutContext);
1341 case MachineJumpTableInfo::EK_BlockAddress:
1342 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
1344 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1346 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
1347 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
1348 // with a relocation as gp-relative, e.g.:
1350 MCSymbol *MBBSym = MBB->getSymbol();
1351 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
1355 case MachineJumpTableInfo::EK_GPRel64BlockAddress: {
1356 // EK_GPRel64BlockAddress - Each entry is an address of block, encoded
1357 // with a relocation as gp-relative, e.g.:
1359 MCSymbol *MBBSym = MBB->getSymbol();
1360 OutStreamer.EmitGPRel64Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
1364 case MachineJumpTableInfo::EK_LabelDifference32: {
1365 // Each entry is the address of the block minus the address of the jump
1366 // table. This is used for PIC jump tables where gprel32 is not supported.
1368 // .word LBB123 - LJTI1_2
1369 // If the .set directive avoids relocations, this is emitted as:
1370 // .set L4_5_set_123, LBB123 - LJTI1_2
1371 // .word L4_5_set_123
1372 if (MAI->doesSetDirectiveSuppressesReloc()) {
1373 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
1377 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1378 const TargetLowering *TLI = MF->getSubtarget().getTargetLowering();
1379 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF, UID, OutContext);
1380 Value = MCBinaryExpr::CreateSub(Value, Base, OutContext);
1385 assert(Value && "Unknown entry kind!");
1387 unsigned EntrySize =
1388 MJTI->getEntrySize(*TM.getDataLayout());
1389 OutStreamer.EmitValue(Value, EntrySize);
1393 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
1394 /// special global used by LLVM. If so, emit it and return true, otherwise
1395 /// do nothing and return false.
1396 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
1397 if (GV->getName() == "llvm.used") {
1398 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
1399 EmitLLVMUsedList(cast<ConstantArray>(GV->getInitializer()));
1403 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
1404 if (StringRef(GV->getSection()) == "llvm.metadata" ||
1405 GV->hasAvailableExternallyLinkage())
1408 if (!GV->hasAppendingLinkage()) return false;
1410 assert(GV->hasInitializer() && "Not a special LLVM global!");
1412 if (GV->getName() == "llvm.global_ctors") {
1413 EmitXXStructorList(GV->getInitializer(), /* isCtor */ true);
1415 if (TM.getRelocationModel() == Reloc::Static &&
1416 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1417 StringRef Sym(".constructors_used");
1418 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1424 if (GV->getName() == "llvm.global_dtors") {
1425 EmitXXStructorList(GV->getInitializer(), /* isCtor */ false);
1427 if (TM.getRelocationModel() == Reloc::Static &&
1428 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1429 StringRef Sym(".destructors_used");
1430 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1439 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
1440 /// global in the specified llvm.used list for which emitUsedDirectiveFor
1441 /// is true, as being used with this directive.
1442 void AsmPrinter::EmitLLVMUsedList(const ConstantArray *InitList) {
1443 // Should be an array of 'i8*'.
1444 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1445 const GlobalValue *GV =
1446 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
1448 OutStreamer.EmitSymbolAttribute(getSymbol(GV), MCSA_NoDeadStrip);
1454 Structor() : Priority(0), Func(nullptr), ComdatKey(nullptr) {}
1456 llvm::Constant *Func;
1457 llvm::GlobalValue *ComdatKey;
1461 /// EmitXXStructorList - Emit the ctor or dtor list taking into account the init
1463 void AsmPrinter::EmitXXStructorList(const Constant *List, bool isCtor) {
1464 // Should be an array of '{ int, void ()* }' structs. The first value is the
1466 if (!isa<ConstantArray>(List)) return;
1468 // Sanity check the structors list.
1469 const ConstantArray *InitList = dyn_cast<ConstantArray>(List);
1470 if (!InitList) return; // Not an array!
1471 StructType *ETy = dyn_cast<StructType>(InitList->getType()->getElementType());
1472 // FIXME: Only allow the 3-field form in LLVM 4.0.
1473 if (!ETy || ETy->getNumElements() < 2 || ETy->getNumElements() > 3)
1474 return; // Not an array of two or three elements!
1475 if (!isa<IntegerType>(ETy->getTypeAtIndex(0U)) ||
1476 !isa<PointerType>(ETy->getTypeAtIndex(1U))) return; // Not (int, ptr).
1477 if (ETy->getNumElements() == 3 && !isa<PointerType>(ETy->getTypeAtIndex(2U)))
1478 return; // Not (int, ptr, ptr).
1480 // Gather the structors in a form that's convenient for sorting by priority.
1481 SmallVector<Structor, 8> Structors;
1482 for (Value *O : InitList->operands()) {
1483 ConstantStruct *CS = dyn_cast<ConstantStruct>(O);
1484 if (!CS) continue; // Malformed.
1485 if (CS->getOperand(1)->isNullValue())
1486 break; // Found a null terminator, skip the rest.
1487 ConstantInt *Priority = dyn_cast<ConstantInt>(CS->getOperand(0));
1488 if (!Priority) continue; // Malformed.
1489 Structors.push_back(Structor());
1490 Structor &S = Structors.back();
1491 S.Priority = Priority->getLimitedValue(65535);
1492 S.Func = CS->getOperand(1);
1493 if (ETy->getNumElements() == 3 && !CS->getOperand(2)->isNullValue())
1494 S.ComdatKey = dyn_cast<GlobalValue>(CS->getOperand(2)->stripPointerCasts());
1497 // Emit the function pointers in the target-specific order
1498 const DataLayout *DL = TM.getDataLayout();
1499 unsigned Align = Log2_32(DL->getPointerPrefAlignment());
1500 std::stable_sort(Structors.begin(), Structors.end(),
1501 [](const Structor &L,
1502 const Structor &R) { return L.Priority < R.Priority; });
1503 for (Structor &S : Structors) {
1504 const TargetLoweringObjectFile &Obj = getObjFileLowering();
1505 const MCSymbol *KeySym = nullptr;
1506 if (GlobalValue *GV = S.ComdatKey) {
1507 if (GV->hasAvailableExternallyLinkage())
1508 // If the associated variable is available_externally, some other TU
1509 // will provide its dynamic initializer.
1512 KeySym = getSymbol(GV);
1514 const MCSection *OutputSection =
1515 (isCtor ? Obj.getStaticCtorSection(S.Priority, KeySym)
1516 : Obj.getStaticDtorSection(S.Priority, KeySym));
1517 OutStreamer.SwitchSection(OutputSection);
1518 if (OutStreamer.getCurrentSection() != OutStreamer.getPreviousSection())
1519 EmitAlignment(Align);
1520 EmitXXStructor(S.Func);
1524 void AsmPrinter::EmitModuleIdents(Module &M) {
1525 if (!MAI->hasIdentDirective())
1528 if (const NamedMDNode *NMD = M.getNamedMetadata("llvm.ident")) {
1529 for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i) {
1530 const MDNode *N = NMD->getOperand(i);
1531 assert(N->getNumOperands() == 1 &&
1532 "llvm.ident metadata entry can have only one operand");
1533 const MDString *S = cast<MDString>(N->getOperand(0));
1534 OutStreamer.EmitIdent(S->getString());
1539 //===--------------------------------------------------------------------===//
1540 // Emission and print routines
1543 /// EmitInt8 - Emit a byte directive and value.
1545 void AsmPrinter::EmitInt8(int Value) const {
1546 OutStreamer.EmitIntValue(Value, 1);
1549 /// EmitInt16 - Emit a short directive and value.
1551 void AsmPrinter::EmitInt16(int Value) const {
1552 OutStreamer.EmitIntValue(Value, 2);
1555 /// EmitInt32 - Emit a long directive and value.
1557 void AsmPrinter::EmitInt32(int Value) const {
1558 OutStreamer.EmitIntValue(Value, 4);
1561 /// Emit something like ".long Hi-Lo" where the size in bytes of the directive
1562 /// is specified by Size and Hi/Lo specify the labels. This implicitly uses
1563 /// .set if it avoids relocations.
1564 void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
1565 unsigned Size) const {
1566 // Get the Hi-Lo expression.
1567 const MCExpr *Diff =
1568 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext),
1569 MCSymbolRefExpr::Create(Lo, OutContext),
1572 if (!MAI->doesSetDirectiveSuppressesReloc()) {
1573 OutStreamer.EmitValue(Diff, Size);
1577 // Otherwise, emit with .set (aka assignment).
1578 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1579 OutStreamer.EmitAssignment(SetLabel, Diff);
1580 OutStreamer.EmitSymbolValue(SetLabel, Size);
1583 /// EmitLabelPlusOffset - Emit something like ".long Label+Offset"
1584 /// where the size in bytes of the directive is specified by Size and Label
1585 /// specifies the label. This implicitly uses .set if it is available.
1586 void AsmPrinter::EmitLabelPlusOffset(const MCSymbol *Label, uint64_t Offset,
1588 bool IsSectionRelative) const {
1589 if (MAI->needsDwarfSectionOffsetDirective() && IsSectionRelative) {
1590 OutStreamer.EmitCOFFSecRel32(Label);
1594 // Emit Label+Offset (or just Label if Offset is zero)
1595 const MCExpr *Expr = MCSymbolRefExpr::Create(Label, OutContext);
1597 Expr = MCBinaryExpr::CreateAdd(
1598 Expr, MCConstantExpr::Create(Offset, OutContext), OutContext);
1600 OutStreamer.EmitValue(Expr, Size);
1603 //===----------------------------------------------------------------------===//
1605 // EmitAlignment - Emit an alignment directive to the specified power of
1606 // two boundary. For example, if you pass in 3 here, you will get an 8
1607 // byte alignment. If a global value is specified, and if that global has
1608 // an explicit alignment requested, it will override the alignment request
1609 // if required for correctness.
1611 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalObject *GV) const {
1613 NumBits = getGVAlignmentLog2(GV, *TM.getDataLayout(),
1616 if (NumBits == 0) return; // 1-byte aligned: no need to emit alignment.
1619 static_cast<unsigned>(std::numeric_limits<unsigned>::digits) &&
1620 "undefined behavior");
1621 if (getCurrentSection()->getKind().isText())
1622 OutStreamer.EmitCodeAlignment(1u << NumBits);
1624 OutStreamer.EmitValueToAlignment(1u << NumBits);
1627 //===----------------------------------------------------------------------===//
1628 // Constant emission.
1629 //===----------------------------------------------------------------------===//
1631 const MCExpr *AsmPrinter::lowerConstant(const Constant *CV) {
1632 MCContext &Ctx = OutContext;
1634 if (CV->isNullValue() || isa<UndefValue>(CV))
1635 return MCConstantExpr::Create(0, Ctx);
1637 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
1638 return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
1640 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
1641 return MCSymbolRefExpr::Create(getSymbol(GV), Ctx);
1643 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
1644 return MCSymbolRefExpr::Create(GetBlockAddressSymbol(BA), Ctx);
1646 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
1648 llvm_unreachable("Unknown constant value to lower!");
1651 if (const MCExpr *RelocExpr
1652 = getObjFileLowering().getExecutableRelativeSymbol(CE, *Mang, TM))
1655 switch (CE->getOpcode()) {
1657 // If the code isn't optimized, there may be outstanding folding
1658 // opportunities. Attempt to fold the expression using DataLayout as a
1659 // last resort before giving up.
1660 if (Constant *C = ConstantFoldConstantExpression(CE, *TM.getDataLayout()))
1662 return lowerConstant(C);
1664 // Otherwise report the problem to the user.
1667 raw_string_ostream OS(S);
1668 OS << "Unsupported expression in static initializer: ";
1669 CE->printAsOperand(OS, /*PrintType=*/false,
1670 !MF ? nullptr : MF->getFunction()->getParent());
1671 report_fatal_error(OS.str());
1673 case Instruction::GetElementPtr: {
1674 const DataLayout &DL = *TM.getDataLayout();
1676 // Generate a symbolic expression for the byte address
1677 APInt OffsetAI(DL.getPointerTypeSizeInBits(CE->getType()), 0);
1678 cast<GEPOperator>(CE)->accumulateConstantOffset(DL, OffsetAI);
1680 const MCExpr *Base = lowerConstant(CE->getOperand(0));
1684 int64_t Offset = OffsetAI.getSExtValue();
1685 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
1689 case Instruction::Trunc:
1690 // We emit the value and depend on the assembler to truncate the generated
1691 // expression properly. This is important for differences between
1692 // blockaddress labels. Since the two labels are in the same function, it
1693 // is reasonable to treat their delta as a 32-bit value.
1695 case Instruction::BitCast:
1696 return lowerConstant(CE->getOperand(0));
1698 case Instruction::IntToPtr: {
1699 const DataLayout &DL = *TM.getDataLayout();
1701 // Handle casts to pointers by changing them into casts to the appropriate
1702 // integer type. This promotes constant folding and simplifies this code.
1703 Constant *Op = CE->getOperand(0);
1704 Op = ConstantExpr::getIntegerCast(Op, DL.getIntPtrType(CV->getType()),
1706 return lowerConstant(Op);
1709 case Instruction::PtrToInt: {
1710 const DataLayout &DL = *TM.getDataLayout();
1712 // Support only foldable casts to/from pointers that can be eliminated by
1713 // changing the pointer to the appropriately sized integer type.
1714 Constant *Op = CE->getOperand(0);
1715 Type *Ty = CE->getType();
1717 const MCExpr *OpExpr = lowerConstant(Op);
1719 // We can emit the pointer value into this slot if the slot is an
1720 // integer slot equal to the size of the pointer.
1721 if (DL.getTypeAllocSize(Ty) == DL.getTypeAllocSize(Op->getType()))
1724 // Otherwise the pointer is smaller than the resultant integer, mask off
1725 // the high bits so we are sure to get a proper truncation if the input is
1727 unsigned InBits = DL.getTypeAllocSizeInBits(Op->getType());
1728 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
1729 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
1732 // The MC library also has a right-shift operator, but it isn't consistently
1733 // signed or unsigned between different targets.
1734 case Instruction::Add:
1735 case Instruction::Sub:
1736 case Instruction::Mul:
1737 case Instruction::SDiv:
1738 case Instruction::SRem:
1739 case Instruction::Shl:
1740 case Instruction::And:
1741 case Instruction::Or:
1742 case Instruction::Xor: {
1743 const MCExpr *LHS = lowerConstant(CE->getOperand(0));
1744 const MCExpr *RHS = lowerConstant(CE->getOperand(1));
1745 switch (CE->getOpcode()) {
1746 default: llvm_unreachable("Unknown binary operator constant cast expr");
1747 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
1748 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
1749 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx);
1750 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx);
1751 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx);
1752 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx);
1753 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
1754 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
1755 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
1761 static void emitGlobalConstantImpl(const Constant *C, AsmPrinter &AP,
1762 const Constant *BaseCV = nullptr,
1763 uint64_t Offset = 0);
1765 /// isRepeatedByteSequence - Determine whether the given value is
1766 /// composed of a repeated sequence of identical bytes and return the
1767 /// byte value. If it is not a repeated sequence, return -1.
1768 static int isRepeatedByteSequence(const ConstantDataSequential *V) {
1769 StringRef Data = V->getRawDataValues();
1770 assert(!Data.empty() && "Empty aggregates should be CAZ node");
1772 for (unsigned i = 1, e = Data.size(); i != e; ++i)
1773 if (Data[i] != C) return -1;
1774 return static_cast<uint8_t>(C); // Ensure 255 is not returned as -1.
1778 /// isRepeatedByteSequence - Determine whether the given value is
1779 /// composed of a repeated sequence of identical bytes and return the
1780 /// byte value. If it is not a repeated sequence, return -1.
1781 static int isRepeatedByteSequence(const Value *V, TargetMachine &TM) {
1783 if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
1784 if (CI->getBitWidth() > 64) return -1;
1787 TM.getDataLayout()->getTypeAllocSize(V->getType());
1788 uint64_t Value = CI->getZExtValue();
1790 // Make sure the constant is at least 8 bits long and has a power
1791 // of 2 bit width. This guarantees the constant bit width is
1792 // always a multiple of 8 bits, avoiding issues with padding out
1793 // to Size and other such corner cases.
1794 if (CI->getBitWidth() < 8 || !isPowerOf2_64(CI->getBitWidth())) return -1;
1796 uint8_t Byte = static_cast<uint8_t>(Value);
1798 for (unsigned i = 1; i < Size; ++i) {
1800 if (static_cast<uint8_t>(Value) != Byte) return -1;
1804 if (const ConstantArray *CA = dyn_cast<ConstantArray>(V)) {
1805 // Make sure all array elements are sequences of the same repeated
1807 assert(CA->getNumOperands() != 0 && "Should be a CAZ");
1808 int Byte = isRepeatedByteSequence(CA->getOperand(0), TM);
1809 if (Byte == -1) return -1;
1811 for (unsigned i = 1, e = CA->getNumOperands(); i != e; ++i) {
1812 int ThisByte = isRepeatedByteSequence(CA->getOperand(i), TM);
1813 if (ThisByte == -1) return -1;
1814 if (Byte != ThisByte) return -1;
1819 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(V))
1820 return isRepeatedByteSequence(CDS);
1825 static void emitGlobalConstantDataSequential(const ConstantDataSequential *CDS,
1828 // See if we can aggregate this into a .fill, if so, emit it as such.
1829 int Value = isRepeatedByteSequence(CDS, AP.TM);
1832 AP.TM.getDataLayout()->getTypeAllocSize(
1834 // Don't emit a 1-byte object as a .fill.
1836 return AP.OutStreamer.EmitFill(Bytes, Value);
1839 // If this can be emitted with .ascii/.asciz, emit it as such.
1840 if (CDS->isString())
1841 return AP.OutStreamer.EmitBytes(CDS->getAsString());
1843 // Otherwise, emit the values in successive locations.
1844 unsigned ElementByteSize = CDS->getElementByteSize();
1845 if (isa<IntegerType>(CDS->getElementType())) {
1846 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1848 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64 "\n",
1849 CDS->getElementAsInteger(i));
1850 AP.OutStreamer.EmitIntValue(CDS->getElementAsInteger(i),
1853 } else if (ElementByteSize == 4) {
1854 // FP Constants are printed as integer constants to avoid losing
1856 assert(CDS->getElementType()->isFloatTy());
1857 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1863 F = CDS->getElementAsFloat(i);
1865 AP.OutStreamer.GetCommentOS() << "float " << F << '\n';
1866 AP.OutStreamer.EmitIntValue(I, 4);
1869 assert(CDS->getElementType()->isDoubleTy());
1870 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1876 F = CDS->getElementAsDouble(i);
1878 AP.OutStreamer.GetCommentOS() << "double " << F << '\n';
1879 AP.OutStreamer.EmitIntValue(I, 8);
1883 const DataLayout &DL = *AP.TM.getDataLayout();
1884 unsigned Size = DL.getTypeAllocSize(CDS->getType());
1885 unsigned EmittedSize = DL.getTypeAllocSize(CDS->getType()->getElementType()) *
1886 CDS->getNumElements();
1887 if (unsigned Padding = Size - EmittedSize)
1888 AP.OutStreamer.EmitZeros(Padding);
1892 static void emitGlobalConstantArray(const ConstantArray *CA, AsmPrinter &AP,
1893 const Constant *BaseCV, uint64_t Offset) {
1894 // See if we can aggregate some values. Make sure it can be
1895 // represented as a series of bytes of the constant value.
1896 int Value = isRepeatedByteSequence(CA, AP.TM);
1897 const DataLayout &DL = *AP.TM.getDataLayout();
1900 uint64_t Bytes = DL.getTypeAllocSize(CA->getType());
1901 AP.OutStreamer.EmitFill(Bytes, Value);
1904 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i) {
1905 emitGlobalConstantImpl(CA->getOperand(i), AP, BaseCV, Offset);
1906 Offset += DL.getTypeAllocSize(CA->getOperand(i)->getType());
1911 static void emitGlobalConstantVector(const ConstantVector *CV, AsmPrinter &AP) {
1912 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1913 emitGlobalConstantImpl(CV->getOperand(i), AP);
1915 const DataLayout &DL = *AP.TM.getDataLayout();
1916 unsigned Size = DL.getTypeAllocSize(CV->getType());
1917 unsigned EmittedSize = DL.getTypeAllocSize(CV->getType()->getElementType()) *
1918 CV->getType()->getNumElements();
1919 if (unsigned Padding = Size - EmittedSize)
1920 AP.OutStreamer.EmitZeros(Padding);
1923 static void emitGlobalConstantStruct(const ConstantStruct *CS, AsmPrinter &AP,
1924 const Constant *BaseCV, uint64_t Offset) {
1925 // Print the fields in successive locations. Pad to align if needed!
1926 const DataLayout *DL = AP.TM.getDataLayout();
1927 unsigned Size = DL->getTypeAllocSize(CS->getType());
1928 const StructLayout *Layout = DL->getStructLayout(CS->getType());
1929 uint64_t SizeSoFar = 0;
1930 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1931 const Constant *Field = CS->getOperand(i);
1933 // Print the actual field value.
1934 emitGlobalConstantImpl(Field, AP, BaseCV, Offset+SizeSoFar);
1936 // Check if padding is needed and insert one or more 0s.
1937 uint64_t FieldSize = DL->getTypeAllocSize(Field->getType());
1938 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1939 - Layout->getElementOffset(i)) - FieldSize;
1940 SizeSoFar += FieldSize + PadSize;
1942 // Insert padding - this may include padding to increase the size of the
1943 // current field up to the ABI size (if the struct is not packed) as well
1944 // as padding to ensure that the next field starts at the right offset.
1945 AP.OutStreamer.EmitZeros(PadSize);
1947 assert(SizeSoFar == Layout->getSizeInBytes() &&
1948 "Layout of constant struct may be incorrect!");
1951 static void emitGlobalConstantFP(const ConstantFP *CFP, AsmPrinter &AP) {
1952 APInt API = CFP->getValueAPF().bitcastToAPInt();
1954 // First print a comment with what we think the original floating-point value
1955 // should have been.
1956 if (AP.isVerbose()) {
1957 SmallString<8> StrVal;
1958 CFP->getValueAPF().toString(StrVal);
1961 CFP->getType()->print(AP.OutStreamer.GetCommentOS());
1963 AP.OutStreamer.GetCommentOS() << "Printing <null> Type";
1964 AP.OutStreamer.GetCommentOS() << ' ' << StrVal << '\n';
1967 // Now iterate through the APInt chunks, emitting them in endian-correct
1968 // order, possibly with a smaller chunk at beginning/end (e.g. for x87 80-bit
1970 unsigned NumBytes = API.getBitWidth() / 8;
1971 unsigned TrailingBytes = NumBytes % sizeof(uint64_t);
1972 const uint64_t *p = API.getRawData();
1974 // PPC's long double has odd notions of endianness compared to how LLVM
1975 // handles it: p[0] goes first for *big* endian on PPC.
1976 if (AP.TM.getDataLayout()->isBigEndian() &&
1977 !CFP->getType()->isPPC_FP128Ty()) {
1978 int Chunk = API.getNumWords() - 1;
1981 AP.OutStreamer.EmitIntValue(p[Chunk--], TrailingBytes);
1983 for (; Chunk >= 0; --Chunk)
1984 AP.OutStreamer.EmitIntValue(p[Chunk], sizeof(uint64_t));
1987 for (Chunk = 0; Chunk < NumBytes / sizeof(uint64_t); ++Chunk)
1988 AP.OutStreamer.EmitIntValue(p[Chunk], sizeof(uint64_t));
1991 AP.OutStreamer.EmitIntValue(p[Chunk], TrailingBytes);
1994 // Emit the tail padding for the long double.
1995 const DataLayout &DL = *AP.TM.getDataLayout();
1996 AP.OutStreamer.EmitZeros(DL.getTypeAllocSize(CFP->getType()) -
1997 DL.getTypeStoreSize(CFP->getType()));
2000 static void emitGlobalConstantLargeInt(const ConstantInt *CI, AsmPrinter &AP) {
2001 const DataLayout *DL = AP.TM.getDataLayout();
2002 unsigned BitWidth = CI->getBitWidth();
2004 // Copy the value as we may massage the layout for constants whose bit width
2005 // is not a multiple of 64-bits.
2006 APInt Realigned(CI->getValue());
2007 uint64_t ExtraBits = 0;
2008 unsigned ExtraBitsSize = BitWidth & 63;
2010 if (ExtraBitsSize) {
2011 // The bit width of the data is not a multiple of 64-bits.
2012 // The extra bits are expected to be at the end of the chunk of the memory.
2014 // * Nothing to be done, just record the extra bits to emit.
2016 // * Record the extra bits to emit.
2017 // * Realign the raw data to emit the chunks of 64-bits.
2018 if (DL->isBigEndian()) {
2019 // Basically the structure of the raw data is a chunk of 64-bits cells:
2020 // 0 1 BitWidth / 64
2021 // [chunk1][chunk2] ... [chunkN].
2022 // The most significant chunk is chunkN and it should be emitted first.
2023 // However, due to the alignment issue chunkN contains useless bits.
2024 // Realign the chunks so that they contain only useless information:
2025 // ExtraBits 0 1 (BitWidth / 64) - 1
2026 // chu[nk1 chu][nk2 chu] ... [nkN-1 chunkN]
2027 ExtraBits = Realigned.getRawData()[0] &
2028 (((uint64_t)-1) >> (64 - ExtraBitsSize));
2029 Realigned = Realigned.lshr(ExtraBitsSize);
2031 ExtraBits = Realigned.getRawData()[BitWidth / 64];
2034 // We don't expect assemblers to support integer data directives
2035 // for more than 64 bits, so we emit the data in at most 64-bit
2036 // quantities at a time.
2037 const uint64_t *RawData = Realigned.getRawData();
2038 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
2039 uint64_t Val = DL->isBigEndian() ? RawData[e - i - 1] : RawData[i];
2040 AP.OutStreamer.EmitIntValue(Val, 8);
2043 if (ExtraBitsSize) {
2044 // Emit the extra bits after the 64-bits chunks.
2046 // Emit a directive that fills the expected size.
2047 uint64_t Size = AP.TM.getDataLayout()->getTypeAllocSize(
2049 Size -= (BitWidth / 64) * 8;
2050 assert(Size && Size * 8 >= ExtraBitsSize &&
2051 (ExtraBits & (((uint64_t)-1) >> (64 - ExtraBitsSize)))
2052 == ExtraBits && "Directive too small for extra bits.");
2053 AP.OutStreamer.EmitIntValue(ExtraBits, Size);
2057 /// \brief Transform a not absolute MCExpr containing a reference to a GOT
2058 /// equivalent global, by a target specific GOT pc relative access to the
2060 static void handleIndirectSymViaGOTPCRel(AsmPrinter &AP, const MCExpr **ME,
2061 const Constant *BaseCst,
2063 // The global @foo below illustrates a global that uses a got equivalent.
2065 // @bar = global i32 42
2066 // @gotequiv = private unnamed_addr constant i32* @bar
2067 // @foo = i32 trunc (i64 sub (i64 ptrtoint (i32** @gotequiv to i64),
2068 // i64 ptrtoint (i32* @foo to i64))
2071 // The cstexpr in @foo is converted into the MCExpr `ME`, where we actually
2072 // check whether @foo is suitable to use a GOTPCREL. `ME` is usually in the
2075 // foo = cstexpr, where
2076 // cstexpr := <gotequiv> - "." + <cst>
2077 // cstexpr := <gotequiv> - (<foo> - <offset from @foo base>) + <cst>
2079 // After canonicalization by EvaluateAsRelocatable `ME` turns into:
2081 // cstexpr := <gotequiv> - <foo> + gotpcrelcst, where
2082 // gotpcrelcst := <offset from @foo base> + <cst>
2085 if (!(*ME)->EvaluateAsRelocatable(MV, nullptr, nullptr) || MV.isAbsolute())
2088 const MCSymbol *GOTEquivSym = &MV.getSymA()->getSymbol();
2089 if (!AP.GlobalGOTEquivs.count(GOTEquivSym))
2092 const GlobalValue *BaseGV = dyn_cast<GlobalValue>(BaseCst);
2096 const MCSymbol *BaseSym = AP.getSymbol(BaseGV);
2097 if (BaseSym != &MV.getSymB()->getSymbol())
2100 // Make sure to match:
2102 // gotpcrelcst := <offset from @foo base> + <cst>
2104 // If gotpcrelcst is positive it means that we can safely fold the pc rel
2105 // displacement into the GOTPCREL. We can also can have an extra offset <cst>
2106 // if the target knows how to encode it.
2108 int64_t GOTPCRelCst = Offset + MV.getConstant();
2109 if (GOTPCRelCst < 0)
2111 if (!AP.getObjFileLowering().supportGOTPCRelWithOffset() && GOTPCRelCst != 0)
2114 // Emit the GOT PC relative to replace the got equivalent global, i.e.:
2121 // .long gotequiv - "." + <cst>
2123 // is replaced by the target specific equivalent to:
2128 // .long bar@GOTPCREL+<gotpcrelcst>
2130 AsmPrinter::GOTEquivUsePair Result = AP.GlobalGOTEquivs[GOTEquivSym];
2131 const GlobalVariable *GV = Result.first;
2132 int NumUses = (int)Result.second;
2133 const GlobalValue *FinalGV = dyn_cast<GlobalValue>(GV->getOperand(0));
2134 const MCSymbol *FinalSym = AP.getSymbol(FinalGV);
2135 *ME = AP.getObjFileLowering().getIndirectSymViaGOTPCRel(
2136 FinalSym, MV, Offset, AP.MMI, AP.OutStreamer);
2138 // Update GOT equivalent usage information
2141 AP.GlobalGOTEquivs[GOTEquivSym] = std::make_pair(GV, NumUses);
2144 static void emitGlobalConstantImpl(const Constant *CV, AsmPrinter &AP,
2145 const Constant *BaseCV, uint64_t Offset) {
2146 const DataLayout *DL = AP.TM.getDataLayout();
2147 uint64_t Size = DL->getTypeAllocSize(CV->getType());
2149 // Globals with sub-elements such as combinations of arrays and structs
2150 // are handled recursively by emitGlobalConstantImpl. Keep track of the
2151 // constant symbol base and the current position with BaseCV and Offset.
2152 if (!BaseCV && CV->hasOneUse())
2153 BaseCV = dyn_cast<Constant>(CV->user_back());
2155 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV))
2156 return AP.OutStreamer.EmitZeros(Size);
2158 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
2165 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64 "\n",
2166 CI->getZExtValue());
2167 AP.OutStreamer.EmitIntValue(CI->getZExtValue(), Size);
2170 emitGlobalConstantLargeInt(CI, AP);
2175 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
2176 return emitGlobalConstantFP(CFP, AP);
2178 if (isa<ConstantPointerNull>(CV)) {
2179 AP.OutStreamer.EmitIntValue(0, Size);
2183 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(CV))
2184 return emitGlobalConstantDataSequential(CDS, AP);
2186 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
2187 return emitGlobalConstantArray(CVA, AP, BaseCV, Offset);
2189 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
2190 return emitGlobalConstantStruct(CVS, AP, BaseCV, Offset);
2192 if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
2193 // Look through bitcasts, which might not be able to be MCExpr'ized (e.g. of
2195 if (CE->getOpcode() == Instruction::BitCast)
2196 return emitGlobalConstantImpl(CE->getOperand(0), AP);
2199 // If the constant expression's size is greater than 64-bits, then we have
2200 // to emit the value in chunks. Try to constant fold the value and emit it
2202 Constant *New = ConstantFoldConstantExpression(CE, *DL);
2203 if (New && New != CE)
2204 return emitGlobalConstantImpl(New, AP);
2208 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
2209 return emitGlobalConstantVector(V, AP);
2211 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
2212 // thread the streamer with EmitValue.
2213 const MCExpr *ME = AP.lowerConstant(CV);
2215 // Since lowerConstant already folded and got rid of all IR pointer and
2216 // integer casts, detect GOT equivalent accesses by looking into the MCExpr
2218 if (AP.getObjFileLowering().supportIndirectSymViaGOTPCRel())
2219 handleIndirectSymViaGOTPCRel(AP, &ME, BaseCV, Offset);
2221 AP.OutStreamer.EmitValue(ME, Size);
2224 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
2225 void AsmPrinter::EmitGlobalConstant(const Constant *CV) {
2227 TM.getDataLayout()->getTypeAllocSize(CV->getType());
2229 emitGlobalConstantImpl(CV, *this);
2230 else if (MAI->hasSubsectionsViaSymbols()) {
2231 // If the global has zero size, emit a single byte so that two labels don't
2232 // look like they are at the same location.
2233 OutStreamer.EmitIntValue(0, 1);
2237 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
2238 // Target doesn't support this yet!
2239 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
2242 void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
2244 OS << '+' << Offset;
2245 else if (Offset < 0)
2249 //===----------------------------------------------------------------------===//
2250 // Symbol Lowering Routines.
2251 //===----------------------------------------------------------------------===//
2253 MCSymbol *AsmPrinter::GetTempSymbol(const Twine &Name, unsigned ID) const {
2254 const DataLayout *DL = TM.getDataLayout();
2255 return OutContext.GetOrCreateSymbol(Twine(DL->getPrivateGlobalPrefix()) +
2259 MCSymbol *AsmPrinter::GetTempSymbol(const Twine &Name) const {
2260 const DataLayout *DL = TM.getDataLayout();
2261 return OutContext.GetOrCreateSymbol(Twine(DL->getPrivateGlobalPrefix())+
2265 MCSymbol *AsmPrinter::createTempSymbol(const Twine &Name, unsigned ID) const {
2266 return OutContext.createTempSymbol(Name + Twine(ID));
2269 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
2270 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
2273 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
2274 return MMI->getAddrLabelSymbol(BB);
2277 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
2278 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
2279 const DataLayout *DL = TM.getDataLayout();
2280 return OutContext.GetOrCreateSymbol
2281 (Twine(DL->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber())
2282 + "_" + Twine(CPID));
2285 /// GetJTISymbol - Return the symbol for the specified jump table entry.
2286 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
2287 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
2290 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
2291 /// FIXME: privatize to AsmPrinter.
2292 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
2293 const DataLayout *DL = TM.getDataLayout();
2294 return OutContext.GetOrCreateSymbol
2295 (Twine(DL->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" +
2296 Twine(UID) + "_set_" + Twine(MBBID));
2299 MCSymbol *AsmPrinter::getSymbolWithGlobalValueBase(const GlobalValue *GV,
2300 StringRef Suffix) const {
2301 return getObjFileLowering().getSymbolWithGlobalValueBase(GV, Suffix, *Mang,
2305 /// GetExternalSymbolSymbol - Return the MCSymbol for the specified
2307 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
2308 SmallString<60> NameStr;
2309 Mang->getNameWithPrefix(NameStr, Sym);
2310 return OutContext.GetOrCreateSymbol(NameStr.str());
2315 /// PrintParentLoopComment - Print comments about parent loops of this one.
2316 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2317 unsigned FunctionNumber) {
2319 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
2320 OS.indent(Loop->getLoopDepth()*2)
2321 << "Parent Loop BB" << FunctionNumber << "_"
2322 << Loop->getHeader()->getNumber()
2323 << " Depth=" << Loop->getLoopDepth() << '\n';
2327 /// PrintChildLoopComment - Print comments about child loops within
2328 /// the loop for this basic block, with nesting.
2329 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2330 unsigned FunctionNumber) {
2331 // Add child loop information
2332 for (const MachineLoop *CL : *Loop) {
2333 OS.indent(CL->getLoopDepth()*2)
2334 << "Child Loop BB" << FunctionNumber << "_"
2335 << CL->getHeader()->getNumber() << " Depth " << CL->getLoopDepth()
2337 PrintChildLoopComment(OS, CL, FunctionNumber);
2341 /// emitBasicBlockLoopComments - Pretty-print comments for basic blocks.
2342 static void emitBasicBlockLoopComments(const MachineBasicBlock &MBB,
2343 const MachineLoopInfo *LI,
2344 const AsmPrinter &AP) {
2345 // Add loop depth information
2346 const MachineLoop *Loop = LI->getLoopFor(&MBB);
2349 MachineBasicBlock *Header = Loop->getHeader();
2350 assert(Header && "No header for loop");
2352 // If this block is not a loop header, just print out what is the loop header
2354 if (Header != &MBB) {
2355 AP.OutStreamer.AddComment(" in Loop: Header=BB" +
2356 Twine(AP.getFunctionNumber())+"_" +
2357 Twine(Loop->getHeader()->getNumber())+
2358 " Depth="+Twine(Loop->getLoopDepth()));
2362 // Otherwise, it is a loop header. Print out information about child and
2364 raw_ostream &OS = AP.OutStreamer.GetCommentOS();
2366 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
2369 OS.indent(Loop->getLoopDepth()*2-2);
2374 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
2376 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
2380 /// EmitBasicBlockStart - This method prints the label for the specified
2381 /// MachineBasicBlock, an alignment (if present) and a comment describing
2382 /// it if appropriate.
2383 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock &MBB) const {
2384 // Emit an alignment directive for this block, if needed.
2385 if (unsigned Align = MBB.getAlignment())
2386 EmitAlignment(Align);
2388 // If the block has its address taken, emit any labels that were used to
2389 // reference the block. It is possible that there is more than one label
2390 // here, because multiple LLVM BB's may have been RAUW'd to this block after
2391 // the references were generated.
2392 if (MBB.hasAddressTaken()) {
2393 const BasicBlock *BB = MBB.getBasicBlock();
2395 OutStreamer.AddComment("Block address taken");
2397 std::vector<MCSymbol*> Symbols = MMI->getAddrLabelSymbolToEmit(BB);
2398 for (auto *Sym : Symbols)
2399 OutStreamer.EmitLabel(Sym);
2402 // Print some verbose block comments.
2404 if (const BasicBlock *BB = MBB.getBasicBlock())
2406 OutStreamer.AddComment("%" + BB->getName());
2407 emitBasicBlockLoopComments(MBB, LI, *this);
2410 // Print the main label for the block.
2411 if (MBB.pred_empty() || isBlockOnlyReachableByFallthrough(&MBB)) {
2413 // NOTE: Want this comment at start of line, don't emit with AddComment.
2414 OutStreamer.emitRawComment(" BB#" + Twine(MBB.getNumber()) + ":", false);
2417 OutStreamer.EmitLabel(MBB.getSymbol());
2421 void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility,
2422 bool IsDefinition) const {
2423 MCSymbolAttr Attr = MCSA_Invalid;
2425 switch (Visibility) {
2427 case GlobalValue::HiddenVisibility:
2429 Attr = MAI->getHiddenVisibilityAttr();
2431 Attr = MAI->getHiddenDeclarationVisibilityAttr();
2433 case GlobalValue::ProtectedVisibility:
2434 Attr = MAI->getProtectedVisibilityAttr();
2438 if (Attr != MCSA_Invalid)
2439 OutStreamer.EmitSymbolAttribute(Sym, Attr);
2442 /// isBlockOnlyReachableByFallthough - Return true if the basic block has
2443 /// exactly one predecessor and the control transfer mechanism between
2444 /// the predecessor and this block is a fall-through.
2446 isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
2447 // If this is a landing pad, it isn't a fall through. If it has no preds,
2448 // then nothing falls through to it.
2449 if (MBB->isLandingPad() || MBB->pred_empty())
2452 // If there isn't exactly one predecessor, it can't be a fall through.
2453 if (MBB->pred_size() > 1)
2456 // The predecessor has to be immediately before this block.
2457 MachineBasicBlock *Pred = *MBB->pred_begin();
2458 if (!Pred->isLayoutSuccessor(MBB))
2461 // If the block is completely empty, then it definitely does fall through.
2465 // Check the terminators in the previous blocks
2466 for (const auto &MI : Pred->terminators()) {
2467 // If it is not a simple branch, we are in a table somewhere.
2468 if (!MI.isBranch() || MI.isIndirectBranch())
2471 // If we are the operands of one of the branches, this is not a fall
2472 // through. Note that targets with delay slots will usually bundle
2473 // terminators with the delay slot instruction.
2474 for (ConstMIBundleOperands OP(&MI); OP.isValid(); ++OP) {
2477 if (OP->isMBB() && OP->getMBB() == MBB)
2487 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy &S) {
2488 if (!S.usesMetadata())
2491 assert(!S.useStatepoints() && "statepoints do not currently support custom"
2492 " stackmap formats, please see the documentation for a description of"
2493 " the default format. If you really need a custom serialized format,"
2494 " please file a bug");
2496 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
2497 gcp_map_type::iterator GCPI = GCMap.find(&S);
2498 if (GCPI != GCMap.end())
2499 return GCPI->second.get();
2501 const char *Name = S.getName().c_str();
2503 for (GCMetadataPrinterRegistry::iterator
2504 I = GCMetadataPrinterRegistry::begin(),
2505 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
2506 if (strcmp(Name, I->getName()) == 0) {
2507 std::unique_ptr<GCMetadataPrinter> GMP = I->instantiate();
2509 auto IterBool = GCMap.insert(std::make_pair(&S, std::move(GMP)));
2510 return IterBool.first->second.get();
2513 report_fatal_error("no GCMetadataPrinter registered for GC: " + Twine(Name));
2516 /// Pin vtable to this file.
2517 AsmPrinterHandler::~AsmPrinterHandler() {}
2519 void AsmPrinterHandler::markFunctionEnd() {}