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 "WinException.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/CodeGen/Analysis.h"
23 #include "llvm/CodeGen/GCMetadataPrinter.h"
24 #include "llvm/CodeGen/MachineConstantPool.h"
25 #include "llvm/CodeGen/MachineFrameInfo.h"
26 #include "llvm/CodeGen/MachineFunction.h"
27 #include "llvm/CodeGen/MachineInstrBundle.h"
28 #include "llvm/CodeGen/MachineJumpTableInfo.h"
29 #include "llvm/CodeGen/MachineLoopInfo.h"
30 #include "llvm/CodeGen/MachineModuleInfoImpls.h"
31 #include "llvm/IR/DataLayout.h"
32 #include "llvm/IR/DebugInfo.h"
33 #include "llvm/IR/Mangler.h"
34 #include "llvm/IR/Module.h"
35 #include "llvm/IR/Operator.h"
36 #include "llvm/MC/MCAsmInfo.h"
37 #include "llvm/MC/MCContext.h"
38 #include "llvm/MC/MCExpr.h"
39 #include "llvm/MC/MCInst.h"
40 #include "llvm/MC/MCSection.h"
41 #include "llvm/MC/MCStreamer.h"
42 #include "llvm/MC/MCSymbolELF.h"
43 #include "llvm/MC/MCValue.h"
44 #include "llvm/Support/ErrorHandling.h"
45 #include "llvm/Support/Format.h"
46 #include "llvm/Support/MathExtras.h"
47 #include "llvm/Support/TargetRegistry.h"
48 #include "llvm/Support/Timer.h"
49 #include "llvm/Target/TargetFrameLowering.h"
50 #include "llvm/Target/TargetInstrInfo.h"
51 #include "llvm/Target/TargetLowering.h"
52 #include "llvm/Target/TargetLoweringObjectFile.h"
53 #include "llvm/Target/TargetRegisterInfo.h"
54 #include "llvm/Target/TargetSubtargetInfo.h"
57 #define DEBUG_TYPE "asm-printer"
59 static const char *const DWARFGroupName = "DWARF Emission";
60 static const char *const DbgTimerName = "Debug Info Emission";
61 static const char *const EHTimerName = "DWARF Exception Writer";
62 static const char *const CodeViewLineTablesGroupName = "CodeView Line Tables";
64 STATISTIC(EmittedInsts, "Number of machine instrs printed");
66 char AsmPrinter::ID = 0;
68 typedef DenseMap<GCStrategy*, std::unique_ptr<GCMetadataPrinter>> gcp_map_type;
69 static gcp_map_type &getGCMap(void *&P) {
71 P = new gcp_map_type();
72 return *(gcp_map_type*)P;
76 /// getGVAlignmentLog2 - Return the alignment to use for the specified global
77 /// value in log2 form. This rounds up to the preferred alignment if possible
79 static unsigned getGVAlignmentLog2(const GlobalValue *GV, const DataLayout &DL,
80 unsigned InBits = 0) {
82 if (const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV))
83 NumBits = DL.getPreferredAlignmentLog(GVar);
85 // If InBits is specified, round it to it.
89 // If the GV has a specified alignment, take it into account.
90 if (GV->getAlignment() == 0)
93 unsigned GVAlign = Log2_32(GV->getAlignment());
95 // If the GVAlign is larger than NumBits, or if we are required to obey
96 // NumBits because the GV has an assigned section, obey it.
97 if (GVAlign > NumBits || GV->hasSection())
102 AsmPrinter::AsmPrinter(TargetMachine &tm, std::unique_ptr<MCStreamer> Streamer)
103 : MachineFunctionPass(ID), TM(tm), MAI(tm.getMCAsmInfo()),
104 OutContext(Streamer->getContext()), OutStreamer(std::move(Streamer)),
105 LastMI(nullptr), LastFn(0), Counter(~0U) {
110 CurExceptionSym = CurrentFnSym = CurrentFnSymForSize = nullptr;
111 CurrentFnBegin = nullptr;
112 CurrentFnEnd = nullptr;
113 GCMetadataPrinters = nullptr;
114 VerboseAsm = OutStreamer->isVerboseAsm();
117 AsmPrinter::~AsmPrinter() {
118 assert(!DD && Handlers.empty() && "Debug/EH info didn't get finalized");
120 if (GCMetadataPrinters) {
121 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
124 GCMetadataPrinters = nullptr;
128 /// getFunctionNumber - Return a unique ID for the current function.
130 unsigned AsmPrinter::getFunctionNumber() const {
131 return MF->getFunctionNumber();
134 const TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
135 return *TM.getObjFileLowering();
138 const DataLayout &AsmPrinter::getDataLayout() const {
139 return MMI->getModule()->getDataLayout();
142 unsigned AsmPrinter::getPointerSize() const {
143 return TM.getDataLayout()->getPointerSize();
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().str();
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>();
178 // Initialize TargetLoweringObjectFile.
179 const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
180 .Initialize(OutContext, TM);
182 OutStreamer->InitSections(false);
184 Mang = new Mangler();
186 // Emit the version-min deplyment target directive if needed.
188 // FIXME: If we end up with a collection of these sorts of Darwin-specific
189 // or ELF-specific things, it may make sense to have a platform helper class
190 // that will work with the target helper class. For now keep it here, as the
191 // alternative is duplicated code in each of the target asm printers that
192 // use the directive, where it would need the same conditionalization
194 Triple TT(getTargetTriple());
195 if (TT.isOSDarwin()) {
196 unsigned Major, Minor, Update;
197 TT.getOSVersion(Major, Minor, Update);
198 // If there is a version specified, Major will be non-zero.
200 OutStreamer->EmitVersionMin((TT.isMacOSX() ?
201 MCVM_OSXVersionMin : MCVM_IOSVersionMin),
202 Major, Minor, Update);
205 // Allow the target to emit any magic that it wants at the start of the file.
206 EmitStartOfAsmFile(M);
208 // Very minimal debug info. It is ignored if we emit actual debug info. If we
209 // don't, this at least helps the user find where a global came from.
210 if (MAI->hasSingleParameterDotFile()) {
212 OutStreamer->EmitFileDirective(M.getModuleIdentifier());
215 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
216 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
218 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
219 MP->beginAssembly(M, *MI, *this);
221 // Emit module-level inline asm if it exists.
222 if (!M.getModuleInlineAsm().empty()) {
223 // We're at the module level. Construct MCSubtarget from the default CPU
224 // and target triple.
225 std::unique_ptr<MCSubtargetInfo> STI(TM.getTarget().createMCSubtargetInfo(
226 TM.getTargetTriple().str(), TM.getTargetCPU(),
227 TM.getTargetFeatureString()));
228 OutStreamer->AddComment("Start of file scope inline assembly");
229 OutStreamer->AddBlankLine();
230 EmitInlineAsm(M.getModuleInlineAsm()+"\n", *STI, TM.Options.MCOptions);
231 OutStreamer->AddComment("End of file scope inline assembly");
232 OutStreamer->AddBlankLine();
235 if (MAI->doesSupportDebugInformation()) {
236 bool skip_dwarf = false;
237 if (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::Invalid:
273 case WinEH::EncodingType::X86:
274 case WinEH::EncodingType::Itanium:
275 ES = new WinException(this);
281 Handlers.push_back(HandlerInfo(ES, EHTimerName, DWARFGroupName));
285 static bool canBeHidden(const GlobalValue *GV, const MCAsmInfo &MAI) {
286 if (!MAI.hasWeakDefCanBeHiddenDirective())
289 return canBeOmittedFromSymbolTable(GV);
292 void AsmPrinter::EmitLinkage(const GlobalValue *GV, MCSymbol *GVSym) const {
293 GlobalValue::LinkageTypes Linkage = GV->getLinkage();
295 case GlobalValue::CommonLinkage:
296 case GlobalValue::LinkOnceAnyLinkage:
297 case GlobalValue::LinkOnceODRLinkage:
298 case GlobalValue::WeakAnyLinkage:
299 case GlobalValue::WeakODRLinkage:
300 if (MAI->hasWeakDefDirective()) {
302 OutStreamer->EmitSymbolAttribute(GVSym, MCSA_Global);
304 if (!canBeHidden(GV, *MAI))
305 // .weak_definition _foo
306 OutStreamer->EmitSymbolAttribute(GVSym, MCSA_WeakDefinition);
308 OutStreamer->EmitSymbolAttribute(GVSym, MCSA_WeakDefAutoPrivate);
309 } else if (MAI->hasLinkOnceDirective()) {
311 OutStreamer->EmitSymbolAttribute(GVSym, MCSA_Global);
312 //NOTE: linkonce is handled by the section the symbol was assigned to.
315 OutStreamer->EmitSymbolAttribute(GVSym, MCSA_Weak);
318 case GlobalValue::AppendingLinkage:
319 // FIXME: appending linkage variables should go into a section of
320 // their name or something. For now, just emit them as external.
321 case GlobalValue::ExternalLinkage:
322 // If external or appending, declare as a global symbol.
324 OutStreamer->EmitSymbolAttribute(GVSym, MCSA_Global);
326 case GlobalValue::PrivateLinkage:
327 case GlobalValue::InternalLinkage:
329 case GlobalValue::AvailableExternallyLinkage:
330 llvm_unreachable("Should never emit this");
331 case GlobalValue::ExternalWeakLinkage:
332 llvm_unreachable("Don't know how to emit these");
334 llvm_unreachable("Unknown linkage type!");
337 void AsmPrinter::getNameWithPrefix(SmallVectorImpl<char> &Name,
338 const GlobalValue *GV) const {
339 TM.getNameWithPrefix(Name, GV, *Mang);
342 MCSymbol *AsmPrinter::getSymbol(const GlobalValue *GV) const {
343 return TM.getSymbol(GV, *Mang);
346 /// EmitGlobalVariable - Emit the specified global variable to the .s file.
347 void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
348 if (GV->hasInitializer()) {
349 // Check to see if this is a special global used by LLVM, if so, emit it.
350 if (EmitSpecialLLVMGlobal(GV))
353 // Skip the emission of global equivalents. The symbol can be emitted later
354 // on by emitGlobalGOTEquivs in case it turns out to be needed.
355 if (GlobalGOTEquivs.count(getSymbol(GV)))
359 GV->printAsOperand(OutStreamer->GetCommentOS(),
360 /*PrintType=*/false, GV->getParent());
361 OutStreamer->GetCommentOS() << '\n';
365 MCSymbol *GVSym = getSymbol(GV);
366 EmitVisibility(GVSym, GV->getVisibility(), !GV->isDeclaration());
368 if (!GV->hasInitializer()) // External globals require no extra code.
371 GVSym->redefineIfPossible();
372 if (GVSym->isDefined() || GVSym->isVariable())
373 report_fatal_error("symbol '" + Twine(GVSym->getName()) +
374 "' is already defined");
376 if (MAI->hasDotTypeDotSizeDirective())
377 OutStreamer->EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
379 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
381 const DataLayout &DL = GV->getParent()->getDataLayout();
382 uint64_t Size = DL.getTypeAllocSize(GV->getType()->getElementType());
384 // If the alignment is specified, we *must* obey it. Overaligning a global
385 // with a specified alignment is a prompt way to break globals emitted to
386 // sections and expected to be contiguous (e.g. ObjC metadata).
387 unsigned AlignLog = getGVAlignmentLog2(GV, DL);
389 for (const HandlerInfo &HI : Handlers) {
390 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled);
391 HI.Handler->setSymbolSize(GVSym, Size);
394 // Handle common and BSS local symbols (.lcomm).
395 if (GVKind.isCommon() || GVKind.isBSSLocal()) {
396 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
397 unsigned Align = 1 << AlignLog;
399 // Handle common symbols.
400 if (GVKind.isCommon()) {
401 if (!getObjFileLowering().getCommDirectiveSupportsAlignment())
405 OutStreamer->EmitCommonSymbol(GVSym, Size, Align);
409 // Handle local BSS symbols.
410 if (MAI->hasMachoZeroFillDirective()) {
411 MCSection *TheSection =
412 getObjFileLowering().SectionForGlobal(GV, GVKind, *Mang, TM);
413 // .zerofill __DATA, __bss, _foo, 400, 5
414 OutStreamer->EmitZerofill(TheSection, GVSym, Size, Align);
418 // Use .lcomm only if it supports user-specified alignment.
419 // Otherwise, while it would still be correct to use .lcomm in some
420 // cases (e.g. when Align == 1), the external assembler might enfore
421 // some -unknown- default alignment behavior, which could cause
422 // spurious differences between external and integrated assembler.
423 // Prefer to simply fall back to .local / .comm in this case.
424 if (MAI->getLCOMMDirectiveAlignmentType() != LCOMM::NoAlignment) {
426 OutStreamer->EmitLocalCommonSymbol(GVSym, Size, Align);
430 if (!getObjFileLowering().getCommDirectiveSupportsAlignment())
434 OutStreamer->EmitSymbolAttribute(GVSym, MCSA_Local);
436 OutStreamer->EmitCommonSymbol(GVSym, Size, Align);
440 MCSection *TheSection =
441 getObjFileLowering().SectionForGlobal(GV, GVKind, *Mang, TM);
443 // Handle the zerofill directive on darwin, which is a special form of BSS
445 if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) {
446 if (Size == 0) Size = 1; // zerofill of 0 bytes is undefined.
449 OutStreamer->EmitSymbolAttribute(GVSym, MCSA_Global);
450 // .zerofill __DATA, __common, _foo, 400, 5
451 OutStreamer->EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
455 // Handle thread local data for mach-o which requires us to output an
456 // additional structure of data and mangle the original symbol so that we
457 // can reference it later.
459 // TODO: This should become an "emit thread local global" method on TLOF.
460 // All of this macho specific stuff should be sunk down into TLOFMachO and
461 // stuff like "TLSExtraDataSection" should no longer be part of the parent
462 // TLOF class. This will also make it more obvious that stuff like
463 // MCStreamer::EmitTBSSSymbol is macho specific and only called from macho
465 if (GVKind.isThreadLocal() && MAI->hasMachoTBSSDirective()) {
466 // Emit the .tbss symbol
468 OutContext.getOrCreateSymbol(GVSym->getName() + Twine("$tlv$init"));
470 if (GVKind.isThreadBSS()) {
471 TheSection = getObjFileLowering().getTLSBSSSection();
472 OutStreamer->EmitTBSSSymbol(TheSection, MangSym, Size, 1 << AlignLog);
473 } else if (GVKind.isThreadData()) {
474 OutStreamer->SwitchSection(TheSection);
476 EmitAlignment(AlignLog, GV);
477 OutStreamer->EmitLabel(MangSym);
479 EmitGlobalConstant(GV->getParent()->getDataLayout(),
480 GV->getInitializer());
483 OutStreamer->AddBlankLine();
485 // Emit the variable struct for the runtime.
486 MCSection *TLVSect = getObjFileLowering().getTLSExtraDataSection();
488 OutStreamer->SwitchSection(TLVSect);
489 // Emit the linkage here.
490 EmitLinkage(GV, GVSym);
491 OutStreamer->EmitLabel(GVSym);
493 // Three pointers in size:
494 // - __tlv_bootstrap - used to make sure support exists
495 // - spare pointer, used when mapped by the runtime
496 // - pointer to mangled symbol above with initializer
497 unsigned PtrSize = DL.getPointerTypeSize(GV->getType());
498 OutStreamer->EmitSymbolValue(GetExternalSymbolSymbol("_tlv_bootstrap"),
500 OutStreamer->EmitIntValue(0, PtrSize);
501 OutStreamer->EmitSymbolValue(MangSym, PtrSize);
503 OutStreamer->AddBlankLine();
507 OutStreamer->SwitchSection(TheSection);
509 EmitLinkage(GV, GVSym);
510 EmitAlignment(AlignLog, GV);
512 OutStreamer->EmitLabel(GVSym);
514 EmitGlobalConstant(GV->getParent()->getDataLayout(), GV->getInitializer());
516 if (MAI->hasDotTypeDotSizeDirective())
518 OutStreamer->emitELFSize(cast<MCSymbolELF>(GVSym),
519 MCConstantExpr::create(Size, OutContext));
521 OutStreamer->AddBlankLine();
524 /// EmitFunctionHeader - This method emits the header for the current
526 void AsmPrinter::EmitFunctionHeader() {
527 // Print out constants referenced by the function
530 // Print the 'header' of function.
531 const Function *F = MF->getFunction();
533 OutStreamer->SwitchSection(
534 getObjFileLowering().SectionForGlobal(F, *Mang, TM));
535 EmitVisibility(CurrentFnSym, F->getVisibility());
537 EmitLinkage(F, CurrentFnSym);
538 if (MAI->hasFunctionAlignment())
539 EmitAlignment(MF->getAlignment(), F);
541 if (MAI->hasDotTypeDotSizeDirective())
542 OutStreamer->EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
545 F->printAsOperand(OutStreamer->GetCommentOS(),
546 /*PrintType=*/false, F->getParent());
547 OutStreamer->GetCommentOS() << '\n';
550 // Emit the prefix data.
551 if (F->hasPrefixData())
552 EmitGlobalConstant(F->getParent()->getDataLayout(), F->getPrefixData());
554 // Emit the CurrentFnSym. This is a virtual function to allow targets to
555 // do their wild and crazy things as required.
556 EmitFunctionEntryLabel();
558 // If the function had address-taken blocks that got deleted, then we have
559 // references to the dangling symbols. Emit them at the start of the function
560 // so that we don't get references to undefined symbols.
561 std::vector<MCSymbol*> DeadBlockSyms;
562 MMI->takeDeletedSymbolsForFunction(F, DeadBlockSyms);
563 for (unsigned i = 0, e = DeadBlockSyms.size(); i != e; ++i) {
564 OutStreamer->AddComment("Address taken block that was later removed");
565 OutStreamer->EmitLabel(DeadBlockSyms[i]);
568 if (CurrentFnBegin) {
569 if (MAI->useAssignmentForEHBegin()) {
570 MCSymbol *CurPos = OutContext.createTempSymbol();
571 OutStreamer->EmitLabel(CurPos);
572 OutStreamer->EmitAssignment(CurrentFnBegin,
573 MCSymbolRefExpr::create(CurPos, OutContext));
575 OutStreamer->EmitLabel(CurrentFnBegin);
579 // Emit pre-function debug and/or EH information.
580 for (const HandlerInfo &HI : Handlers) {
581 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled);
582 HI.Handler->beginFunction(MF);
585 // Emit the prologue data.
586 if (F->hasPrologueData())
587 EmitGlobalConstant(F->getParent()->getDataLayout(), F->getPrologueData());
590 /// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
591 /// function. This can be overridden by targets as required to do custom stuff.
592 void AsmPrinter::EmitFunctionEntryLabel() {
593 CurrentFnSym->redefineIfPossible();
595 // The function label could have already been emitted if two symbols end up
596 // conflicting due to asm renaming. Detect this and emit an error.
597 if (CurrentFnSym->isVariable())
598 report_fatal_error("'" + Twine(CurrentFnSym->getName()) +
599 "' is a protected alias");
600 if (CurrentFnSym->isDefined())
601 report_fatal_error("'" + Twine(CurrentFnSym->getName()) +
602 "' label emitted multiple times to assembly file");
604 return OutStreamer->EmitLabel(CurrentFnSym);
607 /// emitComments - Pretty-print comments for instructions.
608 static void emitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
609 const MachineFunction *MF = MI.getParent()->getParent();
610 const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
612 // Check for spills and reloads
615 const MachineFrameInfo *FrameInfo = MF->getFrameInfo();
617 // We assume a single instruction only has a spill or reload, not
619 const MachineMemOperand *MMO;
620 if (TII->isLoadFromStackSlotPostFE(&MI, FI)) {
621 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
622 MMO = *MI.memoperands_begin();
623 CommentOS << MMO->getSize() << "-byte Reload\n";
625 } else if (TII->hasLoadFromStackSlot(&MI, MMO, FI)) {
626 if (FrameInfo->isSpillSlotObjectIndex(FI))
627 CommentOS << MMO->getSize() << "-byte Folded Reload\n";
628 } else if (TII->isStoreToStackSlotPostFE(&MI, FI)) {
629 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
630 MMO = *MI.memoperands_begin();
631 CommentOS << MMO->getSize() << "-byte Spill\n";
633 } else if (TII->hasStoreToStackSlot(&MI, MMO, FI)) {
634 if (FrameInfo->isSpillSlotObjectIndex(FI))
635 CommentOS << MMO->getSize() << "-byte Folded Spill\n";
638 // Check for spill-induced copies
639 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse))
640 CommentOS << " Reload Reuse\n";
643 /// emitImplicitDef - This method emits the specified machine instruction
644 /// that is an implicit def.
645 void AsmPrinter::emitImplicitDef(const MachineInstr *MI) const {
646 unsigned RegNo = MI->getOperand(0).getReg();
647 OutStreamer->AddComment(Twine("implicit-def: ") +
648 MMI->getContext().getRegisterInfo()->getName(RegNo));
649 OutStreamer->AddBlankLine();
652 static void emitKill(const MachineInstr *MI, AsmPrinter &AP) {
653 std::string Str = "kill:";
654 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
655 const MachineOperand &Op = MI->getOperand(i);
656 assert(Op.isReg() && "KILL instruction must have only register operands");
658 Str += AP.MMI->getContext().getRegisterInfo()->getName(Op.getReg());
659 Str += (Op.isDef() ? "<def>" : "<kill>");
661 AP.OutStreamer->AddComment(Str);
662 AP.OutStreamer->AddBlankLine();
665 /// emitDebugValueComment - This method handles the target-independent form
666 /// of DBG_VALUE, returning true if it was able to do so. A false return
667 /// means the target will need to handle MI in EmitInstruction.
668 static bool emitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) {
669 // This code handles only the 4-operand target-independent form.
670 if (MI->getNumOperands() != 4)
673 SmallString<128> Str;
674 raw_svector_ostream OS(Str);
675 OS << "DEBUG_VALUE: ";
677 const DILocalVariable *V = MI->getDebugVariable();
678 if (auto *SP = dyn_cast<DISubprogram>(V->getScope())) {
679 StringRef Name = SP->getDisplayName();
685 const DIExpression *Expr = MI->getDebugExpression();
686 if (Expr->isBitPiece())
687 OS << " [bit_piece offset=" << Expr->getBitPieceOffset()
688 << " size=" << Expr->getBitPieceSize() << "]";
691 // The second operand is only an offset if it's an immediate.
692 bool Deref = MI->getOperand(0).isReg() && MI->getOperand(1).isImm();
693 int64_t Offset = Deref ? MI->getOperand(1).getImm() : 0;
695 // Register or immediate value. Register 0 means undef.
696 if (MI->getOperand(0).isFPImm()) {
697 APFloat APF = APFloat(MI->getOperand(0).getFPImm()->getValueAPF());
698 if (MI->getOperand(0).getFPImm()->getType()->isFloatTy()) {
699 OS << (double)APF.convertToFloat();
700 } else if (MI->getOperand(0).getFPImm()->getType()->isDoubleTy()) {
701 OS << APF.convertToDouble();
703 // There is no good way to print long double. Convert a copy to
704 // double. Ah well, it's only a comment.
706 APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
708 OS << "(long double) " << APF.convertToDouble();
710 } else if (MI->getOperand(0).isImm()) {
711 OS << MI->getOperand(0).getImm();
712 } else if (MI->getOperand(0).isCImm()) {
713 MI->getOperand(0).getCImm()->getValue().print(OS, false /*isSigned*/);
716 if (MI->getOperand(0).isReg()) {
717 Reg = MI->getOperand(0).getReg();
719 assert(MI->getOperand(0).isFI() && "Unknown operand type");
720 const TargetFrameLowering *TFI = AP.MF->getSubtarget().getFrameLowering();
721 Offset += TFI->getFrameIndexReference(*AP.MF,
722 MI->getOperand(0).getIndex(), Reg);
726 // Suppress offset, it is not meaningful here.
728 // NOTE: Want this comment at start of line, don't emit with AddComment.
729 AP.OutStreamer->emitRawComment(OS.str());
734 OS << AP.MMI->getContext().getRegisterInfo()->getName(Reg);
738 OS << '+' << Offset << ']';
740 // NOTE: Want this comment at start of line, don't emit with AddComment.
741 AP.OutStreamer->emitRawComment(OS.str());
745 AsmPrinter::CFIMoveType AsmPrinter::needsCFIMoves() {
746 if (MAI->getExceptionHandlingType() == ExceptionHandling::DwarfCFI &&
747 MF->getFunction()->needsUnwindTableEntry())
750 if (MMI->hasDebugInfo())
756 bool AsmPrinter::needsSEHMoves() {
757 return MAI->usesWindowsCFI() && MF->getFunction()->needsUnwindTableEntry();
760 void AsmPrinter::emitCFIInstruction(const MachineInstr &MI) {
761 ExceptionHandling ExceptionHandlingType = MAI->getExceptionHandlingType();
762 if (ExceptionHandlingType != ExceptionHandling::DwarfCFI &&
763 ExceptionHandlingType != ExceptionHandling::ARM)
766 if (needsCFIMoves() == CFI_M_None)
769 const MachineModuleInfo &MMI = MF->getMMI();
770 const std::vector<MCCFIInstruction> &Instrs = MMI.getFrameInstructions();
771 unsigned CFIIndex = MI.getOperand(0).getCFIIndex();
772 const MCCFIInstruction &CFI = Instrs[CFIIndex];
773 emitCFIInstruction(CFI);
776 void AsmPrinter::emitFrameAlloc(const MachineInstr &MI) {
777 // The operands are the MCSymbol and the frame offset of the allocation.
778 MCSymbol *FrameAllocSym = MI.getOperand(0).getMCSymbol();
779 int FrameOffset = MI.getOperand(1).getImm();
781 // Emit a symbol assignment.
782 OutStreamer->EmitAssignment(FrameAllocSym,
783 MCConstantExpr::create(FrameOffset, OutContext));
786 /// EmitFunctionBody - This method emits the body and trailer for a
788 void AsmPrinter::EmitFunctionBody() {
789 EmitFunctionHeader();
791 // Emit target-specific gunk before the function body.
792 EmitFunctionBodyStart();
794 bool ShouldPrintDebugScopes = MMI->hasDebugInfo();
796 // Print out code for the function.
797 bool HasAnyRealCode = false;
798 for (auto &MBB : *MF) {
799 // Print a label for the basic block.
800 EmitBasicBlockStart(MBB);
801 for (auto &MI : MBB) {
803 // Print the assembly for the instruction.
804 if (!MI.isPosition() && !MI.isImplicitDef() && !MI.isKill() &&
805 !MI.isDebugValue()) {
806 HasAnyRealCode = true;
810 if (ShouldPrintDebugScopes) {
811 for (const HandlerInfo &HI : Handlers) {
812 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName,
813 TimePassesIsEnabled);
814 HI.Handler->beginInstruction(&MI);
819 emitComments(MI, OutStreamer->GetCommentOS());
821 switch (MI.getOpcode()) {
822 case TargetOpcode::CFI_INSTRUCTION:
823 emitCFIInstruction(MI);
826 case TargetOpcode::LOCAL_ESCAPE:
830 case TargetOpcode::EH_LABEL:
831 case TargetOpcode::GC_LABEL:
832 OutStreamer->EmitLabel(MI.getOperand(0).getMCSymbol());
834 case TargetOpcode::INLINEASM:
837 case TargetOpcode::DBG_VALUE:
839 if (!emitDebugValueComment(&MI, *this))
840 EmitInstruction(&MI);
843 case TargetOpcode::IMPLICIT_DEF:
844 if (isVerbose()) emitImplicitDef(&MI);
846 case TargetOpcode::KILL:
847 if (isVerbose()) emitKill(&MI, *this);
850 EmitInstruction(&MI);
854 if (ShouldPrintDebugScopes) {
855 for (const HandlerInfo &HI : Handlers) {
856 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName,
857 TimePassesIsEnabled);
858 HI.Handler->endInstruction();
863 EmitBasicBlockEnd(MBB);
866 // If the function is empty and the object file uses .subsections_via_symbols,
867 // then we need to emit *something* to the function body to prevent the
868 // labels from collapsing together. Just emit a noop.
869 if ((MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode)) {
871 MF->getSubtarget().getInstrInfo()->getNoopForMachoTarget(Noop);
872 OutStreamer->AddComment("avoids zero-length function");
874 // Targets can opt-out of emitting the noop here by leaving the opcode
876 if (Noop.getOpcode())
877 OutStreamer->EmitInstruction(Noop, getSubtargetInfo());
880 const Function *F = MF->getFunction();
881 for (const auto &BB : *F) {
882 if (!BB.hasAddressTaken())
884 MCSymbol *Sym = GetBlockAddressSymbol(&BB);
885 if (Sym->isDefined())
887 OutStreamer->AddComment("Address of block that was removed by CodeGen");
888 OutStreamer->EmitLabel(Sym);
891 // Emit target-specific gunk after the function body.
892 EmitFunctionBodyEnd();
894 if (!MMI->getLandingPads().empty() || MMI->hasDebugInfo() ||
895 MAI->hasDotTypeDotSizeDirective()) {
896 // Create a symbol for the end of function.
897 CurrentFnEnd = createTempSymbol("func_end");
898 OutStreamer->EmitLabel(CurrentFnEnd);
901 // If the target wants a .size directive for the size of the function, emit
903 if (MAI->hasDotTypeDotSizeDirective()) {
904 // We can get the size as difference between the function label and the
906 const MCExpr *SizeExp = MCBinaryExpr::createSub(
907 MCSymbolRefExpr::create(CurrentFnEnd, OutContext),
908 MCSymbolRefExpr::create(CurrentFnSymForSize, OutContext), OutContext);
909 if (auto Sym = dyn_cast<MCSymbolELF>(CurrentFnSym))
910 OutStreamer->emitELFSize(Sym, SizeExp);
913 for (const HandlerInfo &HI : Handlers) {
914 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled);
915 HI.Handler->markFunctionEnd();
918 // Print out jump tables referenced by the function.
921 // Emit post-function debug and/or EH information.
922 for (const HandlerInfo &HI : Handlers) {
923 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled);
924 HI.Handler->endFunction(MF);
928 OutStreamer->AddBlankLine();
931 /// \brief Compute the number of Global Variables that uses a Constant.
932 static unsigned getNumGlobalVariableUses(const Constant *C) {
936 if (isa<GlobalVariable>(C))
939 unsigned NumUses = 0;
940 for (auto *CU : C->users())
941 NumUses += getNumGlobalVariableUses(dyn_cast<Constant>(CU));
946 /// \brief Only consider global GOT equivalents if at least one user is a
947 /// cstexpr inside an initializer of another global variables. Also, don't
948 /// handle cstexpr inside instructions. During global variable emission,
949 /// candidates are skipped and are emitted later in case at least one cstexpr
950 /// isn't replaced by a PC relative GOT entry access.
951 static bool isGOTEquivalentCandidate(const GlobalVariable *GV,
952 unsigned &NumGOTEquivUsers) {
953 // Global GOT equivalents are unnamed private globals with a constant
954 // pointer initializer to another global symbol. They must point to a
955 // GlobalVariable or Function, i.e., as GlobalValue.
956 if (!GV->hasUnnamedAddr() || !GV->hasInitializer() || !GV->isConstant() ||
957 !GV->isDiscardableIfUnused() || !dyn_cast<GlobalValue>(GV->getOperand(0)))
960 // To be a got equivalent, at least one of its users need to be a constant
961 // expression used by another global variable.
962 for (auto *U : GV->users())
963 NumGOTEquivUsers += getNumGlobalVariableUses(dyn_cast<Constant>(U));
965 return NumGOTEquivUsers > 0;
968 /// \brief Unnamed constant global variables solely contaning a pointer to
969 /// another globals variable is equivalent to a GOT table entry; it contains the
970 /// the address of another symbol. Optimize it and replace accesses to these
971 /// "GOT equivalents" by using the GOT entry for the final global instead.
972 /// Compute GOT equivalent candidates among all global variables to avoid
973 /// emitting them if possible later on, after it use is replaced by a GOT entry
975 void AsmPrinter::computeGlobalGOTEquivs(Module &M) {
976 if (!getObjFileLowering().supportIndirectSymViaGOTPCRel())
979 for (const auto &G : M.globals()) {
980 unsigned NumGOTEquivUsers = 0;
981 if (!isGOTEquivalentCandidate(&G, NumGOTEquivUsers))
984 const MCSymbol *GOTEquivSym = getSymbol(&G);
985 GlobalGOTEquivs[GOTEquivSym] = std::make_pair(&G, NumGOTEquivUsers);
989 /// \brief Constant expressions using GOT equivalent globals may not be eligible
990 /// for PC relative GOT entry conversion, in such cases we need to emit such
991 /// globals we previously omitted in EmitGlobalVariable.
992 void AsmPrinter::emitGlobalGOTEquivs() {
993 if (!getObjFileLowering().supportIndirectSymViaGOTPCRel())
996 SmallVector<const GlobalVariable *, 8> FailedCandidates;
997 for (auto &I : GlobalGOTEquivs) {
998 const GlobalVariable *GV = I.second.first;
999 unsigned Cnt = I.second.second;
1001 FailedCandidates.push_back(GV);
1003 GlobalGOTEquivs.clear();
1005 for (auto *GV : FailedCandidates)
1006 EmitGlobalVariable(GV);
1009 bool AsmPrinter::doFinalization(Module &M) {
1010 // Set the MachineFunction to nullptr so that we can catch attempted
1011 // accesses to MF specific features at the module level and so that
1012 // we can conditionalize accesses based on whether or not it is nullptr.
1015 // Gather all GOT equivalent globals in the module. We really need two
1016 // passes over the globals: one to compute and another to avoid its emission
1017 // in EmitGlobalVariable, otherwise we would not be able to handle cases
1018 // where the got equivalent shows up before its use.
1019 computeGlobalGOTEquivs(M);
1021 // Emit global variables.
1022 for (const auto &G : M.globals())
1023 EmitGlobalVariable(&G);
1025 // Emit remaining GOT equivalent globals.
1026 emitGlobalGOTEquivs();
1028 // Emit visibility info for declarations
1029 for (const Function &F : M) {
1030 if (!F.isDeclarationForLinker())
1032 GlobalValue::VisibilityTypes V = F.getVisibility();
1033 if (V == GlobalValue::DefaultVisibility)
1036 MCSymbol *Name = getSymbol(&F);
1037 EmitVisibility(Name, V, false);
1040 const TargetLoweringObjectFile &TLOF = getObjFileLowering();
1042 // Emit module flags.
1043 SmallVector<Module::ModuleFlagEntry, 8> ModuleFlags;
1044 M.getModuleFlagsMetadata(ModuleFlags);
1045 if (!ModuleFlags.empty())
1046 TLOF.emitModuleFlags(*OutStreamer, ModuleFlags, *Mang, TM);
1048 if (TM.getTargetTriple().isOSBinFormatELF()) {
1049 MachineModuleInfoELF &MMIELF = MMI->getObjFileInfo<MachineModuleInfoELF>();
1051 // Output stubs for external and common global variables.
1052 MachineModuleInfoELF::SymbolListTy Stubs = MMIELF.GetGVStubList();
1053 if (!Stubs.empty()) {
1054 OutStreamer->SwitchSection(TLOF.getDataRelSection());
1055 const DataLayout &DL = M.getDataLayout();
1057 for (const auto &Stub : Stubs) {
1058 OutStreamer->EmitLabel(Stub.first);
1059 OutStreamer->EmitSymbolValue(Stub.second.getPointer(),
1060 DL.getPointerSize());
1065 // Make sure we wrote out everything we need.
1066 OutStreamer->Flush();
1068 // Finalize debug and EH information.
1069 for (const HandlerInfo &HI : Handlers) {
1070 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName,
1071 TimePassesIsEnabled);
1072 HI.Handler->endModule();
1078 // If the target wants to know about weak references, print them all.
1079 if (MAI->getWeakRefDirective()) {
1080 // FIXME: This is not lazy, it would be nice to only print weak references
1081 // to stuff that is actually used. Note that doing so would require targets
1082 // to notice uses in operands (due to constant exprs etc). This should
1083 // happen with the MC stuff eventually.
1085 // Print out module-level global variables here.
1086 for (const auto &G : M.globals()) {
1087 if (!G.hasExternalWeakLinkage())
1089 OutStreamer->EmitSymbolAttribute(getSymbol(&G), MCSA_WeakReference);
1092 for (const auto &F : M) {
1093 if (!F.hasExternalWeakLinkage())
1095 OutStreamer->EmitSymbolAttribute(getSymbol(&F), MCSA_WeakReference);
1099 OutStreamer->AddBlankLine();
1100 for (const auto &Alias : M.aliases()) {
1101 MCSymbol *Name = getSymbol(&Alias);
1103 if (Alias.hasExternalLinkage() || !MAI->getWeakRefDirective())
1104 OutStreamer->EmitSymbolAttribute(Name, MCSA_Global);
1105 else if (Alias.hasWeakLinkage() || Alias.hasLinkOnceLinkage())
1106 OutStreamer->EmitSymbolAttribute(Name, MCSA_WeakReference);
1108 assert(Alias.hasLocalLinkage() && "Invalid alias linkage");
1110 EmitVisibility(Name, Alias.getVisibility());
1112 // Emit the directives as assignments aka .set:
1113 OutStreamer->EmitAssignment(Name, lowerConstant(Alias.getAliasee()));
1115 // Set the size of the alias symbol if we can, as otherwise the alias gets
1116 // the size of the aliasee which may not be correct e.g. if the alias is of
1117 // a member of a struct.
1118 if (MAI->hasDotTypeDotSizeDirective() && Alias.getValueType()->isSized()) {
1119 const DataLayout &DL = M.getDataLayout();
1120 uint64_t Size = DL.getTypeAllocSize(Alias.getValueType());
1121 OutStreamer->emitELFSize(cast<MCSymbolELF>(Name),
1122 MCConstantExpr::create(Size, OutContext));
1126 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
1127 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
1128 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
1129 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(**--I))
1130 MP->finishAssembly(M, *MI, *this);
1132 // Emit llvm.ident metadata in an '.ident' directive.
1133 EmitModuleIdents(M);
1135 // Emit __morestack address if needed for indirect calls.
1136 if (MMI->usesMorestackAddr()) {
1137 MCSection *ReadOnlySection = getObjFileLowering().getSectionForConstant(
1138 getDataLayout(), SectionKind::getReadOnly(),
1140 OutStreamer->SwitchSection(ReadOnlySection);
1142 MCSymbol *AddrSymbol =
1143 OutContext.getOrCreateSymbol(StringRef("__morestack_addr"));
1144 OutStreamer->EmitLabel(AddrSymbol);
1146 unsigned PtrSize = M.getDataLayout().getPointerSize(0);
1147 OutStreamer->EmitSymbolValue(GetExternalSymbolSymbol("__morestack"),
1151 // If we don't have any trampolines, then we don't require stack memory
1152 // to be executable. Some targets have a directive to declare this.
1153 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
1154 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
1155 if (MCSection *S = MAI->getNonexecutableStackSection(OutContext))
1156 OutStreamer->SwitchSection(S);
1158 // Allow the target to emit any magic that it wants at the end of the file,
1159 // after everything else has gone out.
1160 EmitEndOfAsmFile(M);
1162 delete Mang; Mang = nullptr;
1165 OutStreamer->Finish();
1166 OutStreamer->reset();
1171 MCSymbol *AsmPrinter::getCurExceptionSym() {
1172 if (!CurExceptionSym)
1173 CurExceptionSym = createTempSymbol("exception");
1174 return CurExceptionSym;
1177 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
1179 // Get the function symbol.
1180 CurrentFnSym = getSymbol(MF.getFunction());
1181 CurrentFnSymForSize = CurrentFnSym;
1182 CurrentFnBegin = nullptr;
1183 CurExceptionSym = nullptr;
1184 bool NeedsLocalForSize = MAI->needsLocalForSize();
1185 if (!MMI->getLandingPads().empty() || MMI->hasDebugInfo() ||
1186 NeedsLocalForSize) {
1187 CurrentFnBegin = createTempSymbol("func_begin");
1188 if (NeedsLocalForSize)
1189 CurrentFnSymForSize = CurrentFnBegin;
1193 LI = &getAnalysis<MachineLoopInfo>();
1197 // Keep track the alignment, constpool entries per Section.
1201 SmallVector<unsigned, 4> CPEs;
1202 SectionCPs(MCSection *s, unsigned a) : S(s), Alignment(a) {}
1206 /// EmitConstantPool - Print to the current output stream assembly
1207 /// representations of the constants in the constant pool MCP. This is
1208 /// used to print out constants which have been "spilled to memory" by
1209 /// the code generator.
1211 void AsmPrinter::EmitConstantPool() {
1212 const MachineConstantPool *MCP = MF->getConstantPool();
1213 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
1214 if (CP.empty()) return;
1216 // Calculate sections for constant pool entries. We collect entries to go into
1217 // the same section together to reduce amount of section switch statements.
1218 SmallVector<SectionCPs, 4> CPSections;
1219 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
1220 const MachineConstantPoolEntry &CPE = CP[i];
1221 unsigned Align = CPE.getAlignment();
1223 SectionKind Kind = CPE.getSectionKind(&getDataLayout());
1225 const Constant *C = nullptr;
1226 if (!CPE.isMachineConstantPoolEntry())
1227 C = CPE.Val.ConstVal;
1230 getObjFileLowering().getSectionForConstant(getDataLayout(), Kind, C);
1232 // The number of sections are small, just do a linear search from the
1233 // last section to the first.
1235 unsigned SecIdx = CPSections.size();
1236 while (SecIdx != 0) {
1237 if (CPSections[--SecIdx].S == S) {
1243 SecIdx = CPSections.size();
1244 CPSections.push_back(SectionCPs(S, Align));
1247 if (Align > CPSections[SecIdx].Alignment)
1248 CPSections[SecIdx].Alignment = Align;
1249 CPSections[SecIdx].CPEs.push_back(i);
1252 // Now print stuff into the calculated sections.
1253 const MCSection *CurSection = nullptr;
1254 unsigned Offset = 0;
1255 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
1256 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
1257 unsigned CPI = CPSections[i].CPEs[j];
1258 MCSymbol *Sym = GetCPISymbol(CPI);
1259 if (!Sym->isUndefined())
1262 if (CurSection != CPSections[i].S) {
1263 OutStreamer->SwitchSection(CPSections[i].S);
1264 EmitAlignment(Log2_32(CPSections[i].Alignment));
1265 CurSection = CPSections[i].S;
1269 MachineConstantPoolEntry CPE = CP[CPI];
1271 // Emit inter-object padding for alignment.
1272 unsigned AlignMask = CPE.getAlignment() - 1;
1273 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
1274 OutStreamer->EmitZeros(NewOffset - Offset);
1276 Type *Ty = CPE.getType();
1277 Offset = NewOffset + getDataLayout().getTypeAllocSize(Ty);
1279 OutStreamer->EmitLabel(Sym);
1280 if (CPE.isMachineConstantPoolEntry())
1281 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
1283 EmitGlobalConstant(getDataLayout(), CPE.Val.ConstVal);
1288 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
1289 /// by the current function to the current output stream.
1291 void AsmPrinter::EmitJumpTableInfo() {
1292 const DataLayout &DL = MF->getDataLayout();
1293 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
1295 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
1296 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
1297 if (JT.empty()) return;
1299 // Pick the directive to use to print the jump table entries, and switch to
1300 // the appropriate section.
1301 const Function *F = MF->getFunction();
1302 const TargetLoweringObjectFile &TLOF = getObjFileLowering();
1303 bool JTInDiffSection = !TLOF.shouldPutJumpTableInFunctionSection(
1304 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32,
1306 if (JTInDiffSection) {
1307 // Drop it in the readonly section.
1308 MCSection *ReadOnlySection = TLOF.getSectionForJumpTable(*F, *Mang, TM);
1309 OutStreamer->SwitchSection(ReadOnlySection);
1312 EmitAlignment(Log2_32(MJTI->getEntryAlignment(DL)));
1314 // Jump tables in code sections are marked with a data_region directive
1315 // where that's supported.
1316 if (!JTInDiffSection)
1317 OutStreamer->EmitDataRegion(MCDR_DataRegionJT32);
1319 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
1320 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
1322 // If this jump table was deleted, ignore it.
1323 if (JTBBs.empty()) continue;
1325 // For the EK_LabelDifference32 entry, if using .set avoids a relocation,
1326 /// emit a .set directive for each unique entry.
1327 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
1328 MAI->doesSetDirectiveSuppressesReloc()) {
1329 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
1330 const TargetLowering *TLI = MF->getSubtarget().getTargetLowering();
1331 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
1332 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
1333 const MachineBasicBlock *MBB = JTBBs[ii];
1334 if (!EmittedSets.insert(MBB).second)
1337 // .set LJTSet, LBB32-base
1339 MCSymbolRefExpr::create(MBB->getSymbol(), OutContext);
1340 OutStreamer->EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
1341 MCBinaryExpr::createSub(LHS, Base,
1346 // On some targets (e.g. Darwin) we want to emit two consecutive labels
1347 // before each jump table. The first label is never referenced, but tells
1348 // the assembler and linker the extents of the jump table object. The
1349 // second label is actually referenced by the code.
1350 if (JTInDiffSection && DL.hasLinkerPrivateGlobalPrefix())
1351 // FIXME: This doesn't have to have any specific name, just any randomly
1352 // named and numbered 'l' label would work. Simplify GetJTISymbol.
1353 OutStreamer->EmitLabel(GetJTISymbol(JTI, true));
1355 OutStreamer->EmitLabel(GetJTISymbol(JTI));
1357 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
1358 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
1360 if (!JTInDiffSection)
1361 OutStreamer->EmitDataRegion(MCDR_DataRegionEnd);
1364 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
1366 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
1367 const MachineBasicBlock *MBB,
1368 unsigned UID) const {
1369 assert(MBB && MBB->getNumber() >= 0 && "Invalid basic block");
1370 const MCExpr *Value = nullptr;
1371 switch (MJTI->getEntryKind()) {
1372 case MachineJumpTableInfo::EK_Inline:
1373 llvm_unreachable("Cannot emit EK_Inline jump table entry");
1374 case MachineJumpTableInfo::EK_Custom32:
1375 Value = MF->getSubtarget().getTargetLowering()->LowerCustomJumpTableEntry(
1376 MJTI, MBB, UID, OutContext);
1378 case MachineJumpTableInfo::EK_BlockAddress:
1379 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
1381 Value = MCSymbolRefExpr::create(MBB->getSymbol(), OutContext);
1383 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
1384 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
1385 // with a relocation as gp-relative, e.g.:
1387 MCSymbol *MBBSym = MBB->getSymbol();
1388 OutStreamer->EmitGPRel32Value(MCSymbolRefExpr::create(MBBSym, OutContext));
1392 case MachineJumpTableInfo::EK_GPRel64BlockAddress: {
1393 // EK_GPRel64BlockAddress - Each entry is an address of block, encoded
1394 // with a relocation as gp-relative, e.g.:
1396 MCSymbol *MBBSym = MBB->getSymbol();
1397 OutStreamer->EmitGPRel64Value(MCSymbolRefExpr::create(MBBSym, OutContext));
1401 case MachineJumpTableInfo::EK_LabelDifference32: {
1402 // Each entry is the address of the block minus the address of the jump
1403 // table. This is used for PIC jump tables where gprel32 is not supported.
1405 // .word LBB123 - LJTI1_2
1406 // If the .set directive avoids relocations, this is emitted as:
1407 // .set L4_5_set_123, LBB123 - LJTI1_2
1408 // .word L4_5_set_123
1409 if (MAI->doesSetDirectiveSuppressesReloc()) {
1410 Value = MCSymbolRefExpr::create(GetJTSetSymbol(UID, MBB->getNumber()),
1414 Value = MCSymbolRefExpr::create(MBB->getSymbol(), OutContext);
1415 const TargetLowering *TLI = MF->getSubtarget().getTargetLowering();
1416 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF, UID, OutContext);
1417 Value = MCBinaryExpr::createSub(Value, Base, OutContext);
1422 assert(Value && "Unknown entry kind!");
1424 unsigned EntrySize = MJTI->getEntrySize(getDataLayout());
1425 OutStreamer->EmitValue(Value, EntrySize);
1429 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
1430 /// special global used by LLVM. If so, emit it and return true, otherwise
1431 /// do nothing and return false.
1432 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
1433 if (GV->getName() == "llvm.used") {
1434 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
1435 EmitLLVMUsedList(cast<ConstantArray>(GV->getInitializer()));
1439 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
1440 if (StringRef(GV->getSection()) == "llvm.metadata" ||
1441 GV->hasAvailableExternallyLinkage())
1444 if (!GV->hasAppendingLinkage()) return false;
1446 assert(GV->hasInitializer() && "Not a special LLVM global!");
1448 if (GV->getName() == "llvm.global_ctors") {
1449 EmitXXStructorList(GV->getParent()->getDataLayout(), GV->getInitializer(),
1452 if (TM.getRelocationModel() == Reloc::Static &&
1453 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1454 StringRef Sym(".constructors_used");
1455 OutStreamer->EmitSymbolAttribute(OutContext.getOrCreateSymbol(Sym),
1461 if (GV->getName() == "llvm.global_dtors") {
1462 EmitXXStructorList(GV->getParent()->getDataLayout(), GV->getInitializer(),
1463 /* isCtor */ false);
1465 if (TM.getRelocationModel() == Reloc::Static &&
1466 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1467 StringRef Sym(".destructors_used");
1468 OutStreamer->EmitSymbolAttribute(OutContext.getOrCreateSymbol(Sym),
1477 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
1478 /// global in the specified llvm.used list for which emitUsedDirectiveFor
1479 /// is true, as being used with this directive.
1480 void AsmPrinter::EmitLLVMUsedList(const ConstantArray *InitList) {
1481 // Should be an array of 'i8*'.
1482 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1483 const GlobalValue *GV =
1484 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
1486 OutStreamer->EmitSymbolAttribute(getSymbol(GV), MCSA_NoDeadStrip);
1492 Structor() : Priority(0), Func(nullptr), ComdatKey(nullptr) {}
1494 llvm::Constant *Func;
1495 llvm::GlobalValue *ComdatKey;
1499 /// EmitXXStructorList - Emit the ctor or dtor list taking into account the init
1501 void AsmPrinter::EmitXXStructorList(const DataLayout &DL, const Constant *List,
1503 // Should be an array of '{ int, void ()* }' structs. The first value is the
1505 if (!isa<ConstantArray>(List)) return;
1507 // Sanity check the structors list.
1508 const ConstantArray *InitList = dyn_cast<ConstantArray>(List);
1509 if (!InitList) return; // Not an array!
1510 StructType *ETy = dyn_cast<StructType>(InitList->getType()->getElementType());
1511 // FIXME: Only allow the 3-field form in LLVM 4.0.
1512 if (!ETy || ETy->getNumElements() < 2 || ETy->getNumElements() > 3)
1513 return; // Not an array of two or three elements!
1514 if (!isa<IntegerType>(ETy->getTypeAtIndex(0U)) ||
1515 !isa<PointerType>(ETy->getTypeAtIndex(1U))) return; // Not (int, ptr).
1516 if (ETy->getNumElements() == 3 && !isa<PointerType>(ETy->getTypeAtIndex(2U)))
1517 return; // Not (int, ptr, ptr).
1519 // Gather the structors in a form that's convenient for sorting by priority.
1520 SmallVector<Structor, 8> Structors;
1521 for (Value *O : InitList->operands()) {
1522 ConstantStruct *CS = dyn_cast<ConstantStruct>(O);
1523 if (!CS) continue; // Malformed.
1524 if (CS->getOperand(1)->isNullValue())
1525 break; // Found a null terminator, skip the rest.
1526 ConstantInt *Priority = dyn_cast<ConstantInt>(CS->getOperand(0));
1527 if (!Priority) continue; // Malformed.
1528 Structors.push_back(Structor());
1529 Structor &S = Structors.back();
1530 S.Priority = Priority->getLimitedValue(65535);
1531 S.Func = CS->getOperand(1);
1532 if (ETy->getNumElements() == 3 && !CS->getOperand(2)->isNullValue())
1533 S.ComdatKey = dyn_cast<GlobalValue>(CS->getOperand(2)->stripPointerCasts());
1536 // Emit the function pointers in the target-specific order
1537 unsigned Align = Log2_32(DL.getPointerPrefAlignment());
1538 std::stable_sort(Structors.begin(), Structors.end(),
1539 [](const Structor &L,
1540 const Structor &R) { return L.Priority < R.Priority; });
1541 for (Structor &S : Structors) {
1542 const TargetLoweringObjectFile &Obj = getObjFileLowering();
1543 const MCSymbol *KeySym = nullptr;
1544 if (GlobalValue *GV = S.ComdatKey) {
1545 if (GV->hasAvailableExternallyLinkage())
1546 // If the associated variable is available_externally, some other TU
1547 // will provide its dynamic initializer.
1550 KeySym = getSymbol(GV);
1552 MCSection *OutputSection =
1553 (isCtor ? Obj.getStaticCtorSection(S.Priority, KeySym)
1554 : Obj.getStaticDtorSection(S.Priority, KeySym));
1555 OutStreamer->SwitchSection(OutputSection);
1556 if (OutStreamer->getCurrentSection() != OutStreamer->getPreviousSection())
1557 EmitAlignment(Align);
1558 EmitXXStructor(DL, S.Func);
1562 void AsmPrinter::EmitModuleIdents(Module &M) {
1563 if (!MAI->hasIdentDirective())
1566 if (const NamedMDNode *NMD = M.getNamedMetadata("llvm.ident")) {
1567 for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i) {
1568 const MDNode *N = NMD->getOperand(i);
1569 assert(N->getNumOperands() == 1 &&
1570 "llvm.ident metadata entry can have only one operand");
1571 const MDString *S = cast<MDString>(N->getOperand(0));
1572 OutStreamer->EmitIdent(S->getString());
1577 //===--------------------------------------------------------------------===//
1578 // Emission and print routines
1581 /// EmitInt8 - Emit a byte directive and value.
1583 void AsmPrinter::EmitInt8(int Value) const {
1584 OutStreamer->EmitIntValue(Value, 1);
1587 /// EmitInt16 - Emit a short directive and value.
1589 void AsmPrinter::EmitInt16(int Value) const {
1590 OutStreamer->EmitIntValue(Value, 2);
1593 /// EmitInt32 - Emit a long directive and value.
1595 void AsmPrinter::EmitInt32(int Value) const {
1596 OutStreamer->EmitIntValue(Value, 4);
1599 /// Emit something like ".long Hi-Lo" where the size in bytes of the directive
1600 /// is specified by Size and Hi/Lo specify the labels. This implicitly uses
1601 /// .set if it avoids relocations.
1602 void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
1603 unsigned Size) const {
1604 OutStreamer->emitAbsoluteSymbolDiff(Hi, Lo, Size);
1607 /// EmitLabelPlusOffset - Emit something like ".long Label+Offset"
1608 /// where the size in bytes of the directive is specified by Size and Label
1609 /// specifies the label. This implicitly uses .set if it is available.
1610 void AsmPrinter::EmitLabelPlusOffset(const MCSymbol *Label, uint64_t Offset,
1612 bool IsSectionRelative) const {
1613 if (MAI->needsDwarfSectionOffsetDirective() && IsSectionRelative) {
1614 OutStreamer->EmitCOFFSecRel32(Label);
1618 // Emit Label+Offset (or just Label if Offset is zero)
1619 const MCExpr *Expr = MCSymbolRefExpr::create(Label, OutContext);
1621 Expr = MCBinaryExpr::createAdd(
1622 Expr, MCConstantExpr::create(Offset, OutContext), OutContext);
1624 OutStreamer->EmitValue(Expr, Size);
1627 //===----------------------------------------------------------------------===//
1629 // EmitAlignment - Emit an alignment directive to the specified power of
1630 // two boundary. For example, if you pass in 3 here, you will get an 8
1631 // byte alignment. If a global value is specified, and if that global has
1632 // an explicit alignment requested, it will override the alignment request
1633 // if required for correctness.
1635 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalObject *GV) const {
1637 NumBits = getGVAlignmentLog2(GV, GV->getParent()->getDataLayout(), NumBits);
1639 if (NumBits == 0) return; // 1-byte aligned: no need to emit alignment.
1642 static_cast<unsigned>(std::numeric_limits<unsigned>::digits) &&
1643 "undefined behavior");
1644 if (getCurrentSection()->getKind().isText())
1645 OutStreamer->EmitCodeAlignment(1u << NumBits);
1647 OutStreamer->EmitValueToAlignment(1u << NumBits);
1650 //===----------------------------------------------------------------------===//
1651 // Constant emission.
1652 //===----------------------------------------------------------------------===//
1654 const MCExpr *AsmPrinter::lowerConstant(const Constant *CV) {
1655 MCContext &Ctx = OutContext;
1657 if (CV->isNullValue() || isa<UndefValue>(CV))
1658 return MCConstantExpr::create(0, Ctx);
1660 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
1661 return MCConstantExpr::create(CI->getZExtValue(), Ctx);
1663 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
1664 return MCSymbolRefExpr::create(getSymbol(GV), Ctx);
1666 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
1667 return MCSymbolRefExpr::create(GetBlockAddressSymbol(BA), Ctx);
1669 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
1671 llvm_unreachable("Unknown constant value to lower!");
1674 if (const MCExpr *RelocExpr
1675 = getObjFileLowering().getExecutableRelativeSymbol(CE, *Mang, TM))
1678 switch (CE->getOpcode()) {
1680 // If the code isn't optimized, there may be outstanding folding
1681 // opportunities. Attempt to fold the expression using DataLayout as a
1682 // last resort before giving up.
1683 if (Constant *C = ConstantFoldConstantExpression(CE, getDataLayout()))
1685 return lowerConstant(C);
1687 // Otherwise report the problem to the user.
1690 raw_string_ostream OS(S);
1691 OS << "Unsupported expression in static initializer: ";
1692 CE->printAsOperand(OS, /*PrintType=*/false,
1693 !MF ? nullptr : MF->getFunction()->getParent());
1694 report_fatal_error(OS.str());
1696 case Instruction::GetElementPtr: {
1697 // Generate a symbolic expression for the byte address
1698 APInt OffsetAI(getDataLayout().getPointerTypeSizeInBits(CE->getType()), 0);
1699 cast<GEPOperator>(CE)->accumulateConstantOffset(getDataLayout(), OffsetAI);
1701 const MCExpr *Base = lowerConstant(CE->getOperand(0));
1705 int64_t Offset = OffsetAI.getSExtValue();
1706 return MCBinaryExpr::createAdd(Base, MCConstantExpr::create(Offset, Ctx),
1710 case Instruction::Trunc:
1711 // We emit the value and depend on the assembler to truncate the generated
1712 // expression properly. This is important for differences between
1713 // blockaddress labels. Since the two labels are in the same function, it
1714 // is reasonable to treat their delta as a 32-bit value.
1716 case Instruction::BitCast:
1717 return lowerConstant(CE->getOperand(0));
1719 case Instruction::IntToPtr: {
1720 const DataLayout &DL = getDataLayout();
1722 // Handle casts to pointers by changing them into casts to the appropriate
1723 // integer type. This promotes constant folding and simplifies this code.
1724 Constant *Op = CE->getOperand(0);
1725 Op = ConstantExpr::getIntegerCast(Op, DL.getIntPtrType(CV->getType()),
1727 return lowerConstant(Op);
1730 case Instruction::PtrToInt: {
1731 const DataLayout &DL = getDataLayout();
1733 // Support only foldable casts to/from pointers that can be eliminated by
1734 // changing the pointer to the appropriately sized integer type.
1735 Constant *Op = CE->getOperand(0);
1736 Type *Ty = CE->getType();
1738 const MCExpr *OpExpr = lowerConstant(Op);
1740 // We can emit the pointer value into this slot if the slot is an
1741 // integer slot equal to the size of the pointer.
1742 if (DL.getTypeAllocSize(Ty) == DL.getTypeAllocSize(Op->getType()))
1745 // Otherwise the pointer is smaller than the resultant integer, mask off
1746 // the high bits so we are sure to get a proper truncation if the input is
1748 unsigned InBits = DL.getTypeAllocSizeInBits(Op->getType());
1749 const MCExpr *MaskExpr = MCConstantExpr::create(~0ULL >> (64-InBits), Ctx);
1750 return MCBinaryExpr::createAnd(OpExpr, MaskExpr, Ctx);
1753 // The MC library also has a right-shift operator, but it isn't consistently
1754 // signed or unsigned between different targets.
1755 case Instruction::Add:
1756 case Instruction::Sub:
1757 case Instruction::Mul:
1758 case Instruction::SDiv:
1759 case Instruction::SRem:
1760 case Instruction::Shl:
1761 case Instruction::And:
1762 case Instruction::Or:
1763 case Instruction::Xor: {
1764 const MCExpr *LHS = lowerConstant(CE->getOperand(0));
1765 const MCExpr *RHS = lowerConstant(CE->getOperand(1));
1766 switch (CE->getOpcode()) {
1767 default: llvm_unreachable("Unknown binary operator constant cast expr");
1768 case Instruction::Add: return MCBinaryExpr::createAdd(LHS, RHS, Ctx);
1769 case Instruction::Sub: return MCBinaryExpr::createSub(LHS, RHS, Ctx);
1770 case Instruction::Mul: return MCBinaryExpr::createMul(LHS, RHS, Ctx);
1771 case Instruction::SDiv: return MCBinaryExpr::createDiv(LHS, RHS, Ctx);
1772 case Instruction::SRem: return MCBinaryExpr::createMod(LHS, RHS, Ctx);
1773 case Instruction::Shl: return MCBinaryExpr::createShl(LHS, RHS, Ctx);
1774 case Instruction::And: return MCBinaryExpr::createAnd(LHS, RHS, Ctx);
1775 case Instruction::Or: return MCBinaryExpr::createOr (LHS, RHS, Ctx);
1776 case Instruction::Xor: return MCBinaryExpr::createXor(LHS, RHS, Ctx);
1782 static void emitGlobalConstantImpl(const DataLayout &DL, const Constant *C,
1784 const Constant *BaseCV = nullptr,
1785 uint64_t Offset = 0);
1787 /// isRepeatedByteSequence - Determine whether the given value is
1788 /// composed of a repeated sequence of identical bytes and return the
1789 /// byte value. If it is not a repeated sequence, return -1.
1790 static int isRepeatedByteSequence(const ConstantDataSequential *V) {
1791 StringRef Data = V->getRawDataValues();
1792 assert(!Data.empty() && "Empty aggregates should be CAZ node");
1794 for (unsigned i = 1, e = Data.size(); i != e; ++i)
1795 if (Data[i] != C) return -1;
1796 return static_cast<uint8_t>(C); // Ensure 255 is not returned as -1.
1800 /// isRepeatedByteSequence - Determine whether the given value is
1801 /// composed of a repeated sequence of identical bytes and return the
1802 /// byte value. If it is not a repeated sequence, return -1.
1803 static int isRepeatedByteSequence(const Value *V, const DataLayout &DL) {
1804 if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
1805 uint64_t Size = DL.getTypeAllocSizeInBits(V->getType());
1806 assert(Size % 8 == 0);
1808 // Extend the element to take zero padding into account.
1809 APInt Value = CI->getValue().zextOrSelf(Size);
1810 if (!Value.isSplat(8))
1813 return Value.zextOrTrunc(8).getZExtValue();
1815 if (const ConstantArray *CA = dyn_cast<ConstantArray>(V)) {
1816 // Make sure all array elements are sequences of the same repeated
1818 assert(CA->getNumOperands() != 0 && "Should be a CAZ");
1819 Constant *Op0 = CA->getOperand(0);
1820 int Byte = isRepeatedByteSequence(Op0, DL);
1824 // All array elements must be equal.
1825 for (unsigned i = 1, e = CA->getNumOperands(); i != e; ++i)
1826 if (CA->getOperand(i) != Op0)
1831 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(V))
1832 return isRepeatedByteSequence(CDS);
1837 static void emitGlobalConstantDataSequential(const DataLayout &DL,
1838 const ConstantDataSequential *CDS,
1841 // See if we can aggregate this into a .fill, if so, emit it as such.
1842 int Value = isRepeatedByteSequence(CDS, DL);
1844 uint64_t Bytes = DL.getTypeAllocSize(CDS->getType());
1845 // Don't emit a 1-byte object as a .fill.
1847 return AP.OutStreamer->EmitFill(Bytes, Value);
1850 // If this can be emitted with .ascii/.asciz, emit it as such.
1851 if (CDS->isString())
1852 return AP.OutStreamer->EmitBytes(CDS->getAsString());
1854 // Otherwise, emit the values in successive locations.
1855 unsigned ElementByteSize = CDS->getElementByteSize();
1856 if (isa<IntegerType>(CDS->getElementType())) {
1857 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1859 AP.OutStreamer->GetCommentOS() << format("0x%" PRIx64 "\n",
1860 CDS->getElementAsInteger(i));
1861 AP.OutStreamer->EmitIntValue(CDS->getElementAsInteger(i),
1864 } else if (ElementByteSize == 4) {
1865 // FP Constants are printed as integer constants to avoid losing
1867 assert(CDS->getElementType()->isFloatTy());
1868 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1874 F = CDS->getElementAsFloat(i);
1876 AP.OutStreamer->GetCommentOS() << "float " << F << '\n';
1877 AP.OutStreamer->EmitIntValue(I, 4);
1880 assert(CDS->getElementType()->isDoubleTy());
1881 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1887 F = CDS->getElementAsDouble(i);
1889 AP.OutStreamer->GetCommentOS() << "double " << F << '\n';
1890 AP.OutStreamer->EmitIntValue(I, 8);
1894 unsigned Size = DL.getTypeAllocSize(CDS->getType());
1895 unsigned EmittedSize = DL.getTypeAllocSize(CDS->getType()->getElementType()) *
1896 CDS->getNumElements();
1897 if (unsigned Padding = Size - EmittedSize)
1898 AP.OutStreamer->EmitZeros(Padding);
1902 static void emitGlobalConstantArray(const DataLayout &DL,
1903 const ConstantArray *CA, AsmPrinter &AP,
1904 const Constant *BaseCV, uint64_t Offset) {
1905 // See if we can aggregate some values. Make sure it can be
1906 // represented as a series of bytes of the constant value.
1907 int Value = isRepeatedByteSequence(CA, DL);
1910 uint64_t Bytes = DL.getTypeAllocSize(CA->getType());
1911 AP.OutStreamer->EmitFill(Bytes, Value);
1914 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i) {
1915 emitGlobalConstantImpl(DL, CA->getOperand(i), AP, BaseCV, Offset);
1916 Offset += DL.getTypeAllocSize(CA->getOperand(i)->getType());
1921 static void emitGlobalConstantVector(const DataLayout &DL,
1922 const ConstantVector *CV, AsmPrinter &AP) {
1923 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1924 emitGlobalConstantImpl(DL, CV->getOperand(i), AP);
1926 unsigned Size = DL.getTypeAllocSize(CV->getType());
1927 unsigned EmittedSize = DL.getTypeAllocSize(CV->getType()->getElementType()) *
1928 CV->getType()->getNumElements();
1929 if (unsigned Padding = Size - EmittedSize)
1930 AP.OutStreamer->EmitZeros(Padding);
1933 static void emitGlobalConstantStruct(const DataLayout &DL,
1934 const ConstantStruct *CS, AsmPrinter &AP,
1935 const Constant *BaseCV, uint64_t Offset) {
1936 // Print the fields in successive locations. Pad to align if needed!
1937 unsigned Size = DL.getTypeAllocSize(CS->getType());
1938 const StructLayout *Layout = DL.getStructLayout(CS->getType());
1939 uint64_t SizeSoFar = 0;
1940 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1941 const Constant *Field = CS->getOperand(i);
1943 // Print the actual field value.
1944 emitGlobalConstantImpl(DL, Field, AP, BaseCV, Offset + SizeSoFar);
1946 // Check if padding is needed and insert one or more 0s.
1947 uint64_t FieldSize = DL.getTypeAllocSize(Field->getType());
1948 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1949 - Layout->getElementOffset(i)) - FieldSize;
1950 SizeSoFar += FieldSize + PadSize;
1952 // Insert padding - this may include padding to increase the size of the
1953 // current field up to the ABI size (if the struct is not packed) as well
1954 // as padding to ensure that the next field starts at the right offset.
1955 AP.OutStreamer->EmitZeros(PadSize);
1957 assert(SizeSoFar == Layout->getSizeInBytes() &&
1958 "Layout of constant struct may be incorrect!");
1961 static void emitGlobalConstantFP(const ConstantFP *CFP, AsmPrinter &AP) {
1962 APInt API = CFP->getValueAPF().bitcastToAPInt();
1964 // First print a comment with what we think the original floating-point value
1965 // should have been.
1966 if (AP.isVerbose()) {
1967 SmallString<8> StrVal;
1968 CFP->getValueAPF().toString(StrVal);
1971 CFP->getType()->print(AP.OutStreamer->GetCommentOS());
1973 AP.OutStreamer->GetCommentOS() << "Printing <null> Type";
1974 AP.OutStreamer->GetCommentOS() << ' ' << StrVal << '\n';
1977 // Now iterate through the APInt chunks, emitting them in endian-correct
1978 // order, possibly with a smaller chunk at beginning/end (e.g. for x87 80-bit
1980 unsigned NumBytes = API.getBitWidth() / 8;
1981 unsigned TrailingBytes = NumBytes % sizeof(uint64_t);
1982 const uint64_t *p = API.getRawData();
1984 // PPC's long double has odd notions of endianness compared to how LLVM
1985 // handles it: p[0] goes first for *big* endian on PPC.
1986 if (AP.getDataLayout().isBigEndian() && !CFP->getType()->isPPC_FP128Ty()) {
1987 int Chunk = API.getNumWords() - 1;
1990 AP.OutStreamer->EmitIntValue(p[Chunk--], TrailingBytes);
1992 for (; Chunk >= 0; --Chunk)
1993 AP.OutStreamer->EmitIntValue(p[Chunk], sizeof(uint64_t));
1996 for (Chunk = 0; Chunk < NumBytes / sizeof(uint64_t); ++Chunk)
1997 AP.OutStreamer->EmitIntValue(p[Chunk], sizeof(uint64_t));
2000 AP.OutStreamer->EmitIntValue(p[Chunk], TrailingBytes);
2003 // Emit the tail padding for the long double.
2004 const DataLayout &DL = AP.getDataLayout();
2005 AP.OutStreamer->EmitZeros(DL.getTypeAllocSize(CFP->getType()) -
2006 DL.getTypeStoreSize(CFP->getType()));
2009 static void emitGlobalConstantLargeInt(const ConstantInt *CI, AsmPrinter &AP) {
2010 const DataLayout &DL = AP.getDataLayout();
2011 unsigned BitWidth = CI->getBitWidth();
2013 // Copy the value as we may massage the layout for constants whose bit width
2014 // is not a multiple of 64-bits.
2015 APInt Realigned(CI->getValue());
2016 uint64_t ExtraBits = 0;
2017 unsigned ExtraBitsSize = BitWidth & 63;
2019 if (ExtraBitsSize) {
2020 // The bit width of the data is not a multiple of 64-bits.
2021 // The extra bits are expected to be at the end of the chunk of the memory.
2023 // * Nothing to be done, just record the extra bits to emit.
2025 // * Record the extra bits to emit.
2026 // * Realign the raw data to emit the chunks of 64-bits.
2027 if (DL.isBigEndian()) {
2028 // Basically the structure of the raw data is a chunk of 64-bits cells:
2029 // 0 1 BitWidth / 64
2030 // [chunk1][chunk2] ... [chunkN].
2031 // The most significant chunk is chunkN and it should be emitted first.
2032 // However, due to the alignment issue chunkN contains useless bits.
2033 // Realign the chunks so that they contain only useless information:
2034 // ExtraBits 0 1 (BitWidth / 64) - 1
2035 // chu[nk1 chu][nk2 chu] ... [nkN-1 chunkN]
2036 ExtraBits = Realigned.getRawData()[0] &
2037 (((uint64_t)-1) >> (64 - ExtraBitsSize));
2038 Realigned = Realigned.lshr(ExtraBitsSize);
2040 ExtraBits = Realigned.getRawData()[BitWidth / 64];
2043 // We don't expect assemblers to support integer data directives
2044 // for more than 64 bits, so we emit the data in at most 64-bit
2045 // quantities at a time.
2046 const uint64_t *RawData = Realigned.getRawData();
2047 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
2048 uint64_t Val = DL.isBigEndian() ? RawData[e - i - 1] : RawData[i];
2049 AP.OutStreamer->EmitIntValue(Val, 8);
2052 if (ExtraBitsSize) {
2053 // Emit the extra bits after the 64-bits chunks.
2055 // Emit a directive that fills the expected size.
2056 uint64_t Size = AP.getDataLayout().getTypeAllocSize(CI->getType());
2057 Size -= (BitWidth / 64) * 8;
2058 assert(Size && Size * 8 >= ExtraBitsSize &&
2059 (ExtraBits & (((uint64_t)-1) >> (64 - ExtraBitsSize)))
2060 == ExtraBits && "Directive too small for extra bits.");
2061 AP.OutStreamer->EmitIntValue(ExtraBits, Size);
2065 /// \brief Transform a not absolute MCExpr containing a reference to a GOT
2066 /// equivalent global, by a target specific GOT pc relative access to the
2068 static void handleIndirectSymViaGOTPCRel(AsmPrinter &AP, const MCExpr **ME,
2069 const Constant *BaseCst,
2071 // The global @foo below illustrates a global that uses a got equivalent.
2073 // @bar = global i32 42
2074 // @gotequiv = private unnamed_addr constant i32* @bar
2075 // @foo = i32 trunc (i64 sub (i64 ptrtoint (i32** @gotequiv to i64),
2076 // i64 ptrtoint (i32* @foo to i64))
2079 // The cstexpr in @foo is converted into the MCExpr `ME`, where we actually
2080 // check whether @foo is suitable to use a GOTPCREL. `ME` is usually in the
2083 // foo = cstexpr, where
2084 // cstexpr := <gotequiv> - "." + <cst>
2085 // cstexpr := <gotequiv> - (<foo> - <offset from @foo base>) + <cst>
2087 // After canonicalization by evaluateAsRelocatable `ME` turns into:
2089 // cstexpr := <gotequiv> - <foo> + gotpcrelcst, where
2090 // gotpcrelcst := <offset from @foo base> + <cst>
2093 if (!(*ME)->evaluateAsRelocatable(MV, nullptr, nullptr) || MV.isAbsolute())
2095 const MCSymbolRefExpr *SymA = MV.getSymA();
2099 // Check that GOT equivalent symbol is cached.
2100 const MCSymbol *GOTEquivSym = &SymA->getSymbol();
2101 if (!AP.GlobalGOTEquivs.count(GOTEquivSym))
2104 const GlobalValue *BaseGV = dyn_cast_or_null<GlobalValue>(BaseCst);
2108 // Check for a valid base symbol
2109 const MCSymbol *BaseSym = AP.getSymbol(BaseGV);
2110 const MCSymbolRefExpr *SymB = MV.getSymB();
2112 if (!SymB || BaseSym != &SymB->getSymbol())
2115 // Make sure to match:
2117 // gotpcrelcst := <offset from @foo base> + <cst>
2119 // If gotpcrelcst is positive it means that we can safely fold the pc rel
2120 // displacement into the GOTPCREL. We can also can have an extra offset <cst>
2121 // if the target knows how to encode it.
2123 int64_t GOTPCRelCst = Offset + MV.getConstant();
2124 if (GOTPCRelCst < 0)
2126 if (!AP.getObjFileLowering().supportGOTPCRelWithOffset() && GOTPCRelCst != 0)
2129 // Emit the GOT PC relative to replace the got equivalent global, i.e.:
2136 // .long gotequiv - "." + <cst>
2138 // is replaced by the target specific equivalent to:
2143 // .long bar@GOTPCREL+<gotpcrelcst>
2145 AsmPrinter::GOTEquivUsePair Result = AP.GlobalGOTEquivs[GOTEquivSym];
2146 const GlobalVariable *GV = Result.first;
2147 int NumUses = (int)Result.second;
2148 const GlobalValue *FinalGV = dyn_cast<GlobalValue>(GV->getOperand(0));
2149 const MCSymbol *FinalSym = AP.getSymbol(FinalGV);
2150 *ME = AP.getObjFileLowering().getIndirectSymViaGOTPCRel(
2151 FinalSym, MV, Offset, AP.MMI, *AP.OutStreamer);
2153 // Update GOT equivalent usage information
2156 AP.GlobalGOTEquivs[GOTEquivSym] = std::make_pair(GV, NumUses);
2159 static void emitGlobalConstantImpl(const DataLayout &DL, const Constant *CV,
2160 AsmPrinter &AP, const Constant *BaseCV,
2162 uint64_t Size = DL.getTypeAllocSize(CV->getType());
2164 // Globals with sub-elements such as combinations of arrays and structs
2165 // are handled recursively by emitGlobalConstantImpl. Keep track of the
2166 // constant symbol base and the current position with BaseCV and Offset.
2167 if (!BaseCV && CV->hasOneUse())
2168 BaseCV = dyn_cast<Constant>(CV->user_back());
2170 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV))
2171 return AP.OutStreamer->EmitZeros(Size);
2173 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
2180 AP.OutStreamer->GetCommentOS() << format("0x%" PRIx64 "\n",
2181 CI->getZExtValue());
2182 AP.OutStreamer->EmitIntValue(CI->getZExtValue(), Size);
2185 emitGlobalConstantLargeInt(CI, AP);
2190 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
2191 return emitGlobalConstantFP(CFP, AP);
2193 if (isa<ConstantPointerNull>(CV)) {
2194 AP.OutStreamer->EmitIntValue(0, Size);
2198 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(CV))
2199 return emitGlobalConstantDataSequential(DL, CDS, AP);
2201 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
2202 return emitGlobalConstantArray(DL, CVA, AP, BaseCV, Offset);
2204 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
2205 return emitGlobalConstantStruct(DL, CVS, AP, BaseCV, Offset);
2207 if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
2208 // Look through bitcasts, which might not be able to be MCExpr'ized (e.g. of
2210 if (CE->getOpcode() == Instruction::BitCast)
2211 return emitGlobalConstantImpl(DL, CE->getOperand(0), AP);
2214 // If the constant expression's size is greater than 64-bits, then we have
2215 // to emit the value in chunks. Try to constant fold the value and emit it
2217 Constant *New = ConstantFoldConstantExpression(CE, DL);
2218 if (New && New != CE)
2219 return emitGlobalConstantImpl(DL, New, AP);
2223 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
2224 return emitGlobalConstantVector(DL, V, AP);
2226 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
2227 // thread the streamer with EmitValue.
2228 const MCExpr *ME = AP.lowerConstant(CV);
2230 // Since lowerConstant already folded and got rid of all IR pointer and
2231 // integer casts, detect GOT equivalent accesses by looking into the MCExpr
2233 if (AP.getObjFileLowering().supportIndirectSymViaGOTPCRel())
2234 handleIndirectSymViaGOTPCRel(AP, &ME, BaseCV, Offset);
2236 AP.OutStreamer->EmitValue(ME, Size);
2239 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
2240 void AsmPrinter::EmitGlobalConstant(const DataLayout &DL, const Constant *CV) {
2241 uint64_t Size = DL.getTypeAllocSize(CV->getType());
2243 emitGlobalConstantImpl(DL, CV, *this);
2244 else if (MAI->hasSubsectionsViaSymbols()) {
2245 // If the global has zero size, emit a single byte so that two labels don't
2246 // look like they are at the same location.
2247 OutStreamer->EmitIntValue(0, 1);
2251 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
2252 // Target doesn't support this yet!
2253 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
2256 void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
2258 OS << '+' << Offset;
2259 else if (Offset < 0)
2263 //===----------------------------------------------------------------------===//
2264 // Symbol Lowering Routines.
2265 //===----------------------------------------------------------------------===//
2267 MCSymbol *AsmPrinter::createTempSymbol(const Twine &Name) const {
2268 return OutContext.createTempSymbol(Name, true);
2271 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
2272 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
2275 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
2276 return MMI->getAddrLabelSymbol(BB);
2279 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
2280 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
2281 const DataLayout &DL = getDataLayout();
2282 return OutContext.getOrCreateSymbol(Twine(DL.getPrivateGlobalPrefix()) +
2283 "CPI" + Twine(getFunctionNumber()) + "_" +
2287 /// GetJTISymbol - Return the symbol for the specified jump table entry.
2288 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
2289 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
2292 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
2293 /// FIXME: privatize to AsmPrinter.
2294 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
2295 const DataLayout &DL = getDataLayout();
2296 return OutContext.getOrCreateSymbol(Twine(DL.getPrivateGlobalPrefix()) +
2297 Twine(getFunctionNumber()) + "_" +
2298 Twine(UID) + "_set_" + Twine(MBBID));
2301 MCSymbol *AsmPrinter::getSymbolWithGlobalValueBase(const GlobalValue *GV,
2302 StringRef Suffix) const {
2303 return getObjFileLowering().getSymbolWithGlobalValueBase(GV, Suffix, *Mang,
2307 /// Return the MCSymbol for the specified ExternalSymbol.
2308 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
2309 SmallString<60> NameStr;
2310 Mangler::getNameWithPrefix(NameStr, Sym, getDataLayout());
2311 return OutContext.getOrCreateSymbol(NameStr);
2316 /// PrintParentLoopComment - Print comments about parent loops of this one.
2317 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2318 unsigned FunctionNumber) {
2320 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
2321 OS.indent(Loop->getLoopDepth()*2)
2322 << "Parent Loop BB" << FunctionNumber << "_"
2323 << Loop->getHeader()->getNumber()
2324 << " Depth=" << Loop->getLoopDepth() << '\n';
2328 /// PrintChildLoopComment - Print comments about child loops within
2329 /// the loop for this basic block, with nesting.
2330 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2331 unsigned FunctionNumber) {
2332 // Add child loop information
2333 for (const MachineLoop *CL : *Loop) {
2334 OS.indent(CL->getLoopDepth()*2)
2335 << "Child Loop BB" << FunctionNumber << "_"
2336 << CL->getHeader()->getNumber() << " Depth " << CL->getLoopDepth()
2338 PrintChildLoopComment(OS, CL, FunctionNumber);
2342 /// emitBasicBlockLoopComments - Pretty-print comments for basic blocks.
2343 static void emitBasicBlockLoopComments(const MachineBasicBlock &MBB,
2344 const MachineLoopInfo *LI,
2345 const AsmPrinter &AP) {
2346 // Add loop depth information
2347 const MachineLoop *Loop = LI->getLoopFor(&MBB);
2350 MachineBasicBlock *Header = Loop->getHeader();
2351 assert(Header && "No header for loop");
2353 // If this block is not a loop header, just print out what is the loop header
2355 if (Header != &MBB) {
2356 AP.OutStreamer->AddComment(" in Loop: Header=BB" +
2357 Twine(AP.getFunctionNumber())+"_" +
2358 Twine(Loop->getHeader()->getNumber())+
2359 " Depth="+Twine(Loop->getLoopDepth()));
2363 // Otherwise, it is a loop header. Print out information about child and
2365 raw_ostream &OS = AP.OutStreamer->GetCommentOS();
2367 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
2370 OS.indent(Loop->getLoopDepth()*2-2);
2375 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
2377 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
2381 /// EmitBasicBlockStart - This method prints the label for the specified
2382 /// MachineBasicBlock, an alignment (if present) and a comment describing
2383 /// it if appropriate.
2384 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock &MBB) const {
2385 // Emit an alignment directive for this block, if needed.
2386 if (unsigned Align = MBB.getAlignment())
2387 EmitAlignment(Align);
2389 // If the block has its address taken, emit any labels that were used to
2390 // reference the block. It is possible that there is more than one label
2391 // here, because multiple LLVM BB's may have been RAUW'd to this block after
2392 // the references were generated.
2393 if (MBB.hasAddressTaken()) {
2394 const BasicBlock *BB = MBB.getBasicBlock();
2396 OutStreamer->AddComment("Block address taken");
2398 for (MCSymbol *Sym : MMI->getAddrLabelSymbolToEmit(BB))
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() {}