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/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/MachineModuleInfoImpls.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/MCSymbolELF.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(std::move(Streamer)),
106 LastMI(nullptr), LastFn(0), Counter(~0U) {
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;
129 /// getFunctionNumber - Return a unique ID for the current function.
131 unsigned AsmPrinter::getFunctionNumber() const {
132 return MF->getFunctionNumber();
135 const TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
136 return *TM.getObjFileLowering();
139 /// getDataLayout - Return information about data layout.
140 const DataLayout &AsmPrinter::getDataLayout() const {
141 return *TM.getDataLayout();
144 const MCSubtargetInfo &AsmPrinter::getSubtargetInfo() const {
145 assert(MF && "getSubtargetInfo requires a valid MachineFunction!");
146 return MF->getSubtarget<MCSubtargetInfo>();
149 void AsmPrinter::EmitToStreamer(MCStreamer &S, const MCInst &Inst) {
150 S.EmitInstruction(Inst, getSubtargetInfo());
153 StringRef AsmPrinter::getTargetTriple() const {
154 return TM.getTargetTriple().str();
157 /// getCurrentSection() - Return the current section we are emitting to.
158 const MCSection *AsmPrinter::getCurrentSection() const {
159 return OutStreamer->getCurrentSection().first;
164 void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
165 AU.setPreservesAll();
166 MachineFunctionPass::getAnalysisUsage(AU);
167 AU.addRequired<MachineModuleInfo>();
168 AU.addRequired<GCModuleInfo>();
170 AU.addRequired<MachineLoopInfo>();
173 bool AsmPrinter::doInitialization(Module &M) {
174 MMI = getAnalysisIfAvailable<MachineModuleInfo>();
176 // Initialize TargetLoweringObjectFile.
177 const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
178 .Initialize(OutContext, TM);
180 OutStreamer->InitSections(false);
182 Mang = new Mangler();
184 // Emit the version-min deplyment target directive if needed.
186 // FIXME: If we end up with a collection of these sorts of Darwin-specific
187 // or ELF-specific things, it may make sense to have a platform helper class
188 // that will work with the target helper class. For now keep it here, as the
189 // alternative is duplicated code in each of the target asm printers that
190 // use the directive, where it would need the same conditionalization
192 Triple TT(getTargetTriple());
193 if (TT.isOSDarwin()) {
194 unsigned Major, Minor, Update;
195 TT.getOSVersion(Major, Minor, Update);
196 // If there is a version specified, Major will be non-zero.
198 OutStreamer->EmitVersionMin((TT.isMacOSX() ?
199 MCVM_OSXVersionMin : MCVM_IOSVersionMin),
200 Major, Minor, Update);
203 // Allow the target to emit any magic that it wants at the start of the file.
204 EmitStartOfAsmFile(M);
206 // Very minimal debug info. It is ignored if we emit actual debug info. If we
207 // don't, this at least helps the user find where a global came from.
208 if (MAI->hasSingleParameterDotFile()) {
210 OutStreamer->EmitFileDirective(M.getModuleIdentifier());
213 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
214 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
216 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
217 MP->beginAssembly(M, *MI, *this);
219 // Emit module-level inline asm if it exists.
220 if (!M.getModuleInlineAsm().empty()) {
221 // We're at the module level. Construct MCSubtarget from the default CPU
222 // and target triple.
223 std::unique_ptr<MCSubtargetInfo> STI(TM.getTarget().createMCSubtargetInfo(
224 TM.getTargetTriple().str(), TM.getTargetCPU(),
225 TM.getTargetFeatureString()));
226 OutStreamer->AddComment("Start of file scope inline assembly");
227 OutStreamer->AddBlankLine();
228 EmitInlineAsm(M.getModuleInlineAsm()+"\n", *STI, TM.Options.MCOptions);
229 OutStreamer->AddComment("End of file scope inline assembly");
230 OutStreamer->AddBlankLine();
233 if (MAI->doesSupportDebugInformation()) {
234 bool skip_dwarf = false;
235 if (TM.getTargetTriple().isKnownWindowsMSVCEnvironment()) {
236 Handlers.push_back(HandlerInfo(new WinCodeViewLineTables(this),
238 CodeViewLineTablesGroupName));
239 // FIXME: Don't emit DWARF debug info if there's at least one function
240 // with AddressSanitizer instrumentation.
241 // This is a band-aid fix for PR22032.
242 for (auto &F : M.functions()) {
243 if (F.hasFnAttribute(Attribute::SanitizeAddress)) {
250 DD = new DwarfDebug(this, &M);
251 Handlers.push_back(HandlerInfo(DD, DbgTimerName, DWARFGroupName));
255 EHStreamer *ES = nullptr;
256 switch (MAI->getExceptionHandlingType()) {
257 case ExceptionHandling::None:
259 case ExceptionHandling::SjLj:
260 case ExceptionHandling::DwarfCFI:
261 ES = new DwarfCFIException(this);
263 case ExceptionHandling::ARM:
264 ES = new ARMException(this);
266 case ExceptionHandling::WinEH:
267 switch (MAI->getWinEHEncodingType()) {
268 default: llvm_unreachable("unsupported unwinding information encoding");
269 case WinEH::EncodingType::Invalid:
271 case WinEH::EncodingType::X86:
272 case WinEH::EncodingType::Itanium:
273 ES = new WinException(this);
279 Handlers.push_back(HandlerInfo(ES, EHTimerName, DWARFGroupName));
283 static bool canBeHidden(const GlobalValue *GV, const MCAsmInfo &MAI) {
284 if (!MAI.hasWeakDefCanBeHiddenDirective())
287 return canBeOmittedFromSymbolTable(GV);
290 void AsmPrinter::EmitLinkage(const GlobalValue *GV, MCSymbol *GVSym) const {
291 GlobalValue::LinkageTypes Linkage = GV->getLinkage();
293 case GlobalValue::CommonLinkage:
294 case GlobalValue::LinkOnceAnyLinkage:
295 case GlobalValue::LinkOnceODRLinkage:
296 case GlobalValue::WeakAnyLinkage:
297 case GlobalValue::WeakODRLinkage:
298 if (MAI->hasWeakDefDirective()) {
300 OutStreamer->EmitSymbolAttribute(GVSym, MCSA_Global);
302 if (!canBeHidden(GV, *MAI))
303 // .weak_definition _foo
304 OutStreamer->EmitSymbolAttribute(GVSym, MCSA_WeakDefinition);
306 OutStreamer->EmitSymbolAttribute(GVSym, MCSA_WeakDefAutoPrivate);
307 } else if (MAI->hasLinkOnceDirective()) {
309 OutStreamer->EmitSymbolAttribute(GVSym, MCSA_Global);
310 //NOTE: linkonce is handled by the section the symbol was assigned to.
313 OutStreamer->EmitSymbolAttribute(GVSym, MCSA_Weak);
316 case GlobalValue::AppendingLinkage:
317 // FIXME: appending linkage variables should go into a section of
318 // their name or something. For now, just emit them as external.
319 case GlobalValue::ExternalLinkage:
320 // If external or appending, declare as a global symbol.
322 OutStreamer->EmitSymbolAttribute(GVSym, MCSA_Global);
324 case GlobalValue::PrivateLinkage:
325 case GlobalValue::InternalLinkage:
327 case GlobalValue::AvailableExternallyLinkage:
328 llvm_unreachable("Should never emit this");
329 case GlobalValue::ExternalWeakLinkage:
330 llvm_unreachable("Don't know how to emit these");
332 llvm_unreachable("Unknown linkage type!");
335 void AsmPrinter::getNameWithPrefix(SmallVectorImpl<char> &Name,
336 const GlobalValue *GV) const {
337 TM.getNameWithPrefix(Name, GV, *Mang);
340 MCSymbol *AsmPrinter::getSymbol(const GlobalValue *GV) const {
341 return TM.getSymbol(GV, *Mang);
344 /// EmitGlobalVariable - Emit the specified global variable to the .s file.
345 void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
346 if (GV->hasInitializer()) {
347 // Check to see if this is a special global used by LLVM, if so, emit it.
348 if (EmitSpecialLLVMGlobal(GV))
351 // Skip the emission of global equivalents. The symbol can be emitted later
352 // on by emitGlobalGOTEquivs in case it turns out to be needed.
353 if (GlobalGOTEquivs.count(getSymbol(GV)))
357 GV->printAsOperand(OutStreamer->GetCommentOS(),
358 /*PrintType=*/false, GV->getParent());
359 OutStreamer->GetCommentOS() << '\n';
363 MCSymbol *GVSym = getSymbol(GV);
364 EmitVisibility(GVSym, GV->getVisibility(), !GV->isDeclaration());
366 if (!GV->hasInitializer()) // External globals require no extra code.
369 GVSym->redefineIfPossible();
370 if (GVSym->isDefined() || GVSym->isVariable())
371 report_fatal_error("symbol '" + Twine(GVSym->getName()) +
372 "' is already defined");
374 if (MAI->hasDotTypeDotSizeDirective())
375 OutStreamer->EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
377 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
379 const DataLayout *DL = TM.getDataLayout();
380 uint64_t Size = DL->getTypeAllocSize(GV->getType()->getElementType());
382 // If the alignment is specified, we *must* obey it. Overaligning a global
383 // with a specified alignment is a prompt way to break globals emitted to
384 // sections and expected to be contiguous (e.g. ObjC metadata).
385 unsigned AlignLog = getGVAlignmentLog2(GV, *DL);
387 for (const HandlerInfo &HI : Handlers) {
388 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled);
389 HI.Handler->setSymbolSize(GVSym, Size);
392 // Handle common and BSS local symbols (.lcomm).
393 if (GVKind.isCommon() || GVKind.isBSSLocal()) {
394 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
395 unsigned Align = 1 << AlignLog;
397 // Handle common symbols.
398 if (GVKind.isCommon()) {
399 if (!getObjFileLowering().getCommDirectiveSupportsAlignment())
403 OutStreamer->EmitCommonSymbol(GVSym, Size, Align);
407 // Handle local BSS symbols.
408 if (MAI->hasMachoZeroFillDirective()) {
409 MCSection *TheSection =
410 getObjFileLowering().SectionForGlobal(GV, GVKind, *Mang, TM);
411 // .zerofill __DATA, __bss, _foo, 400, 5
412 OutStreamer->EmitZerofill(TheSection, GVSym, Size, Align);
416 // Use .lcomm only if it supports user-specified alignment.
417 // Otherwise, while it would still be correct to use .lcomm in some
418 // cases (e.g. when Align == 1), the external assembler might enfore
419 // some -unknown- default alignment behavior, which could cause
420 // spurious differences between external and integrated assembler.
421 // Prefer to simply fall back to .local / .comm in this case.
422 if (MAI->getLCOMMDirectiveAlignmentType() != LCOMM::NoAlignment) {
424 OutStreamer->EmitLocalCommonSymbol(GVSym, Size, Align);
428 if (!getObjFileLowering().getCommDirectiveSupportsAlignment())
432 OutStreamer->EmitSymbolAttribute(GVSym, MCSA_Local);
434 OutStreamer->EmitCommonSymbol(GVSym, Size, Align);
438 MCSection *TheSection =
439 getObjFileLowering().SectionForGlobal(GV, GVKind, *Mang, TM);
441 // Handle the zerofill directive on darwin, which is a special form of BSS
443 if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) {
444 if (Size == 0) Size = 1; // zerofill of 0 bytes is undefined.
447 OutStreamer->EmitSymbolAttribute(GVSym, MCSA_Global);
448 // .zerofill __DATA, __common, _foo, 400, 5
449 OutStreamer->EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
453 // Handle thread local data for mach-o which requires us to output an
454 // additional structure of data and mangle the original symbol so that we
455 // can reference it later.
457 // TODO: This should become an "emit thread local global" method on TLOF.
458 // All of this macho specific stuff should be sunk down into TLOFMachO and
459 // stuff like "TLSExtraDataSection" should no longer be part of the parent
460 // TLOF class. This will also make it more obvious that stuff like
461 // MCStreamer::EmitTBSSSymbol is macho specific and only called from macho
463 if (GVKind.isThreadLocal() && MAI->hasMachoTBSSDirective()) {
464 // Emit the .tbss symbol
466 OutContext.getOrCreateSymbol(GVSym->getName() + Twine("$tlv$init"));
468 if (GVKind.isThreadBSS()) {
469 TheSection = getObjFileLowering().getTLSBSSSection();
470 OutStreamer->EmitTBSSSymbol(TheSection, MangSym, Size, 1 << AlignLog);
471 } else if (GVKind.isThreadData()) {
472 OutStreamer->SwitchSection(TheSection);
474 EmitAlignment(AlignLog, GV);
475 OutStreamer->EmitLabel(MangSym);
477 EmitGlobalConstant(GV->getInitializer());
480 OutStreamer->AddBlankLine();
482 // Emit the variable struct for the runtime.
483 MCSection *TLVSect = 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(cast<MCSymbolELF>(GVSym),
516 MCConstantExpr::create(Size, OutContext));
518 OutStreamer->AddBlankLine();
521 /// EmitFunctionHeader - This method emits the header for the current
523 void AsmPrinter::EmitFunctionHeader() {
524 // Print out constants referenced by the function
527 // Print the 'header' of function.
528 const Function *F = MF->getFunction();
530 OutStreamer->SwitchSection(
531 getObjFileLowering().SectionForGlobal(F, *Mang, TM));
532 EmitVisibility(CurrentFnSym, F->getVisibility());
534 EmitLinkage(F, CurrentFnSym);
535 if (MAI->hasFunctionAlignment())
536 EmitAlignment(MF->getAlignment(), F);
538 if (MAI->hasDotTypeDotSizeDirective())
539 OutStreamer->EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
542 F->printAsOperand(OutStreamer->GetCommentOS(),
543 /*PrintType=*/false, F->getParent());
544 OutStreamer->GetCommentOS() << '\n';
547 // Emit the prefix data.
548 if (F->hasPrefixData())
549 EmitGlobalConstant(F->getPrefixData());
551 // Emit the CurrentFnSym. This is a virtual function to allow targets to
552 // do their wild and crazy things as required.
553 EmitFunctionEntryLabel();
555 // If the function had address-taken blocks that got deleted, then we have
556 // references to the dangling symbols. Emit them at the start of the function
557 // so that we don't get references to undefined symbols.
558 std::vector<MCSymbol*> DeadBlockSyms;
559 MMI->takeDeletedSymbolsForFunction(F, DeadBlockSyms);
560 for (unsigned i = 0, e = DeadBlockSyms.size(); i != e; ++i) {
561 OutStreamer->AddComment("Address taken block that was later removed");
562 OutStreamer->EmitLabel(DeadBlockSyms[i]);
565 if (CurrentFnBegin) {
566 if (MAI->useAssignmentForEHBegin()) {
567 MCSymbol *CurPos = OutContext.createTempSymbol();
568 OutStreamer->EmitLabel(CurPos);
569 OutStreamer->EmitAssignment(CurrentFnBegin,
570 MCSymbolRefExpr::create(CurPos, OutContext));
572 OutStreamer->EmitLabel(CurrentFnBegin);
576 // Emit pre-function debug and/or EH information.
577 for (const HandlerInfo &HI : Handlers) {
578 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled);
579 HI.Handler->beginFunction(MF);
582 // Emit the prologue data.
583 if (F->hasPrologueData())
584 EmitGlobalConstant(F->getPrologueData());
587 /// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
588 /// function. This can be overridden by targets as required to do custom stuff.
589 void AsmPrinter::EmitFunctionEntryLabel() {
590 CurrentFnSym->redefineIfPossible();
592 // The function label could have already been emitted if two symbols end up
593 // conflicting due to asm renaming. Detect this and emit an error.
594 if (CurrentFnSym->isVariable())
595 report_fatal_error("'" + Twine(CurrentFnSym->getName()) +
596 "' is a protected alias");
597 if (CurrentFnSym->isDefined())
598 report_fatal_error("'" + Twine(CurrentFnSym->getName()) +
599 "' label emitted multiple times to assembly file");
601 return OutStreamer->EmitLabel(CurrentFnSym);
604 /// emitComments - Pretty-print comments for instructions.
605 static void emitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
606 const MachineFunction *MF = MI.getParent()->getParent();
607 const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
609 // Check for spills and reloads
612 const MachineFrameInfo *FrameInfo = MF->getFrameInfo();
614 // We assume a single instruction only has a spill or reload, not
616 const MachineMemOperand *MMO;
617 if (TII->isLoadFromStackSlotPostFE(&MI, FI)) {
618 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
619 MMO = *MI.memoperands_begin();
620 CommentOS << MMO->getSize() << "-byte Reload\n";
622 } else if (TII->hasLoadFromStackSlot(&MI, MMO, FI)) {
623 if (FrameInfo->isSpillSlotObjectIndex(FI))
624 CommentOS << MMO->getSize() << "-byte Folded Reload\n";
625 } else if (TII->isStoreToStackSlotPostFE(&MI, FI)) {
626 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
627 MMO = *MI.memoperands_begin();
628 CommentOS << MMO->getSize() << "-byte Spill\n";
630 } else if (TII->hasStoreToStackSlot(&MI, MMO, FI)) {
631 if (FrameInfo->isSpillSlotObjectIndex(FI))
632 CommentOS << MMO->getSize() << "-byte Folded Spill\n";
635 // Check for spill-induced copies
636 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse))
637 CommentOS << " Reload Reuse\n";
640 /// emitImplicitDef - This method emits the specified machine instruction
641 /// that is an implicit def.
642 void AsmPrinter::emitImplicitDef(const MachineInstr *MI) const {
643 unsigned RegNo = MI->getOperand(0).getReg();
644 OutStreamer->AddComment(Twine("implicit-def: ") +
645 MMI->getContext().getRegisterInfo()->getName(RegNo));
646 OutStreamer->AddBlankLine();
649 static void emitKill(const MachineInstr *MI, AsmPrinter &AP) {
650 std::string Str = "kill:";
651 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
652 const MachineOperand &Op = MI->getOperand(i);
653 assert(Op.isReg() && "KILL instruction must have only register operands");
655 Str += AP.MMI->getContext().getRegisterInfo()->getName(Op.getReg());
656 Str += (Op.isDef() ? "<def>" : "<kill>");
658 AP.OutStreamer->AddComment(Str);
659 AP.OutStreamer->AddBlankLine();
662 /// emitDebugValueComment - This method handles the target-independent form
663 /// of DBG_VALUE, returning true if it was able to do so. A false return
664 /// means the target will need to handle MI in EmitInstruction.
665 static bool emitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) {
666 // This code handles only the 4-operand target-independent form.
667 if (MI->getNumOperands() != 4)
670 SmallString<128> Str;
671 raw_svector_ostream OS(Str);
672 OS << "DEBUG_VALUE: ";
674 const DILocalVariable *V = MI->getDebugVariable();
675 if (auto *SP = dyn_cast<DISubprogram>(V->getScope())) {
676 StringRef Name = SP->getDisplayName();
682 const DIExpression *Expr = MI->getDebugExpression();
683 if (Expr->isBitPiece())
684 OS << " [bit_piece offset=" << Expr->getBitPieceOffset()
685 << " size=" << Expr->getBitPieceSize() << "]";
688 // The second operand is only an offset if it's an immediate.
689 bool Deref = MI->getOperand(0).isReg() && MI->getOperand(1).isImm();
690 int64_t Offset = Deref ? MI->getOperand(1).getImm() : 0;
692 // Register or immediate value. Register 0 means undef.
693 if (MI->getOperand(0).isFPImm()) {
694 APFloat APF = APFloat(MI->getOperand(0).getFPImm()->getValueAPF());
695 if (MI->getOperand(0).getFPImm()->getType()->isFloatTy()) {
696 OS << (double)APF.convertToFloat();
697 } else if (MI->getOperand(0).getFPImm()->getType()->isDoubleTy()) {
698 OS << APF.convertToDouble();
700 // There is no good way to print long double. Convert a copy to
701 // double. Ah well, it's only a comment.
703 APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
705 OS << "(long double) " << APF.convertToDouble();
707 } else if (MI->getOperand(0).isImm()) {
708 OS << MI->getOperand(0).getImm();
709 } else if (MI->getOperand(0).isCImm()) {
710 MI->getOperand(0).getCImm()->getValue().print(OS, false /*isSigned*/);
713 if (MI->getOperand(0).isReg()) {
714 Reg = MI->getOperand(0).getReg();
716 assert(MI->getOperand(0).isFI() && "Unknown operand type");
717 const TargetFrameLowering *TFI = AP.MF->getSubtarget().getFrameLowering();
718 Offset += TFI->getFrameIndexReference(*AP.MF,
719 MI->getOperand(0).getIndex(), Reg);
723 // Suppress offset, it is not meaningful here.
725 // NOTE: Want this comment at start of line, don't emit with AddComment.
726 AP.OutStreamer->emitRawComment(OS.str());
731 OS << AP.MMI->getContext().getRegisterInfo()->getName(Reg);
735 OS << '+' << Offset << ']';
737 // NOTE: Want this comment at start of line, don't emit with AddComment.
738 AP.OutStreamer->emitRawComment(OS.str());
742 AsmPrinter::CFIMoveType AsmPrinter::needsCFIMoves() {
743 if (MAI->getExceptionHandlingType() == ExceptionHandling::DwarfCFI &&
744 MF->getFunction()->needsUnwindTableEntry())
747 if (MMI->hasDebugInfo())
753 bool AsmPrinter::needsSEHMoves() {
754 return MAI->usesWindowsCFI() && MF->getFunction()->needsUnwindTableEntry();
757 void AsmPrinter::emitCFIInstruction(const MachineInstr &MI) {
758 ExceptionHandling ExceptionHandlingType = MAI->getExceptionHandlingType();
759 if (ExceptionHandlingType != ExceptionHandling::DwarfCFI &&
760 ExceptionHandlingType != ExceptionHandling::ARM)
763 if (needsCFIMoves() == CFI_M_None)
766 const MachineModuleInfo &MMI = MF->getMMI();
767 const std::vector<MCCFIInstruction> &Instrs = MMI.getFrameInstructions();
768 unsigned CFIIndex = MI.getOperand(0).getCFIIndex();
769 const MCCFIInstruction &CFI = Instrs[CFIIndex];
770 emitCFIInstruction(CFI);
773 void AsmPrinter::emitFrameAlloc(const MachineInstr &MI) {
774 // The operands are the MCSymbol and the frame offset of the allocation.
775 MCSymbol *FrameAllocSym = MI.getOperand(0).getMCSymbol();
776 int FrameOffset = MI.getOperand(1).getImm();
778 // Emit a symbol assignment.
779 OutStreamer->EmitAssignment(FrameAllocSym,
780 MCConstantExpr::create(FrameOffset, OutContext));
783 /// EmitFunctionBody - This method emits the body and trailer for a
785 void AsmPrinter::EmitFunctionBody() {
786 EmitFunctionHeader();
788 // Emit target-specific gunk before the function body.
789 EmitFunctionBodyStart();
791 bool ShouldPrintDebugScopes = MMI->hasDebugInfo();
793 // Print out code for the function.
794 bool HasAnyRealCode = false;
795 for (auto &MBB : *MF) {
796 // Print a label for the basic block.
797 EmitBasicBlockStart(MBB);
798 for (auto &MI : MBB) {
800 // Print the assembly for the instruction.
801 if (!MI.isPosition() && !MI.isImplicitDef() && !MI.isKill() &&
802 !MI.isDebugValue()) {
803 HasAnyRealCode = true;
807 if (ShouldPrintDebugScopes) {
808 for (const HandlerInfo &HI : Handlers) {
809 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName,
810 TimePassesIsEnabled);
811 HI.Handler->beginInstruction(&MI);
816 emitComments(MI, OutStreamer->GetCommentOS());
818 switch (MI.getOpcode()) {
819 case TargetOpcode::CFI_INSTRUCTION:
820 emitCFIInstruction(MI);
823 case TargetOpcode::FRAME_ALLOC:
827 case TargetOpcode::EH_LABEL:
828 case TargetOpcode::GC_LABEL:
829 OutStreamer->EmitLabel(MI.getOperand(0).getMCSymbol());
831 case TargetOpcode::INLINEASM:
834 case TargetOpcode::DBG_VALUE:
836 if (!emitDebugValueComment(&MI, *this))
837 EmitInstruction(&MI);
840 case TargetOpcode::IMPLICIT_DEF:
841 if (isVerbose()) emitImplicitDef(&MI);
843 case TargetOpcode::KILL:
844 if (isVerbose()) emitKill(&MI, *this);
847 EmitInstruction(&MI);
851 if (ShouldPrintDebugScopes) {
852 for (const HandlerInfo &HI : Handlers) {
853 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName,
854 TimePassesIsEnabled);
855 HI.Handler->endInstruction();
860 EmitBasicBlockEnd(MBB);
863 // If the function is empty and the object file uses .subsections_via_symbols,
864 // then we need to emit *something* to the function body to prevent the
865 // labels from collapsing together. Just emit a noop.
866 if ((MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode)) {
868 MF->getSubtarget().getInstrInfo()->getNoopForMachoTarget(Noop);
869 OutStreamer->AddComment("avoids zero-length function");
871 // Targets can opt-out of emitting the noop here by leaving the opcode
873 if (Noop.getOpcode())
874 OutStreamer->EmitInstruction(Noop, getSubtargetInfo());
877 const Function *F = MF->getFunction();
878 for (const auto &BB : *F) {
879 if (!BB.hasAddressTaken())
881 MCSymbol *Sym = GetBlockAddressSymbol(&BB);
882 if (Sym->isDefined())
884 OutStreamer->AddComment("Address of block that was removed by CodeGen");
885 OutStreamer->EmitLabel(Sym);
888 // Emit target-specific gunk after the function body.
889 EmitFunctionBodyEnd();
891 if (!MMI->getLandingPads().empty() || MMI->hasDebugInfo() ||
892 MAI->hasDotTypeDotSizeDirective()) {
893 // Create a symbol for the end of function.
894 CurrentFnEnd = createTempSymbol("func_end");
895 OutStreamer->EmitLabel(CurrentFnEnd);
898 // If the target wants a .size directive for the size of the function, emit
900 if (MAI->hasDotTypeDotSizeDirective()) {
901 // We can get the size as difference between the function label and the
903 const MCExpr *SizeExp = MCBinaryExpr::createSub(
904 MCSymbolRefExpr::create(CurrentFnEnd, OutContext),
905 MCSymbolRefExpr::create(CurrentFnSymForSize, OutContext), OutContext);
906 if (auto Sym = dyn_cast<MCSymbolELF>(CurrentFnSym))
907 OutStreamer->emitELFSize(Sym, SizeExp);
910 for (const HandlerInfo &HI : Handlers) {
911 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled);
912 HI.Handler->markFunctionEnd();
915 // Print out jump tables referenced by the function.
918 // Emit post-function debug and/or EH information.
919 for (const HandlerInfo &HI : Handlers) {
920 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled);
921 HI.Handler->endFunction(MF);
925 OutStreamer->AddBlankLine();
928 /// \brief Compute the number of Global Variables that uses a Constant.
929 static unsigned getNumGlobalVariableUses(const Constant *C) {
933 if (isa<GlobalVariable>(C))
936 unsigned NumUses = 0;
937 for (auto *CU : C->users())
938 NumUses += getNumGlobalVariableUses(dyn_cast<Constant>(CU));
943 /// \brief Only consider global GOT equivalents if at least one user is a
944 /// cstexpr inside an initializer of another global variables. Also, don't
945 /// handle cstexpr inside instructions. During global variable emission,
946 /// candidates are skipped and are emitted later in case at least one cstexpr
947 /// isn't replaced by a PC relative GOT entry access.
948 static bool isGOTEquivalentCandidate(const GlobalVariable *GV,
949 unsigned &NumGOTEquivUsers) {
950 // Global GOT equivalents are unnamed private globals with a constant
951 // pointer initializer to another global symbol. They must point to a
952 // GlobalVariable or Function, i.e., as GlobalValue.
953 if (!GV->hasUnnamedAddr() || !GV->hasInitializer() || !GV->isConstant() ||
954 !GV->isDiscardableIfUnused() || !dyn_cast<GlobalValue>(GV->getOperand(0)))
957 // To be a got equivalent, at least one of its users need to be a constant
958 // expression used by another global variable.
959 for (auto *U : GV->users())
960 NumGOTEquivUsers += getNumGlobalVariableUses(dyn_cast<Constant>(U));
962 return NumGOTEquivUsers > 0;
965 /// \brief Unnamed constant global variables solely contaning a pointer to
966 /// another globals variable is equivalent to a GOT table entry; it contains the
967 /// the address of another symbol. Optimize it and replace accesses to these
968 /// "GOT equivalents" by using the GOT entry for the final global instead.
969 /// Compute GOT equivalent candidates among all global variables to avoid
970 /// emitting them if possible later on, after it use is replaced by a GOT entry
972 void AsmPrinter::computeGlobalGOTEquivs(Module &M) {
973 if (!getObjFileLowering().supportIndirectSymViaGOTPCRel())
976 for (const auto &G : M.globals()) {
977 unsigned NumGOTEquivUsers = 0;
978 if (!isGOTEquivalentCandidate(&G, NumGOTEquivUsers))
981 const MCSymbol *GOTEquivSym = getSymbol(&G);
982 GlobalGOTEquivs[GOTEquivSym] = std::make_pair(&G, NumGOTEquivUsers);
986 /// \brief Constant expressions using GOT equivalent globals may not be eligible
987 /// for PC relative GOT entry conversion, in such cases we need to emit such
988 /// globals we previously omitted in EmitGlobalVariable.
989 void AsmPrinter::emitGlobalGOTEquivs() {
990 if (!getObjFileLowering().supportIndirectSymViaGOTPCRel())
993 SmallVector<const GlobalVariable *, 8> FailedCandidates;
994 for (auto &I : GlobalGOTEquivs) {
995 const GlobalVariable *GV = I.second.first;
996 unsigned Cnt = I.second.second;
998 FailedCandidates.push_back(GV);
1000 GlobalGOTEquivs.clear();
1002 for (auto *GV : FailedCandidates)
1003 EmitGlobalVariable(GV);
1006 bool AsmPrinter::doFinalization(Module &M) {
1007 // Set the MachineFunction to nullptr so that we can catch attempted
1008 // accesses to MF specific features at the module level and so that
1009 // we can conditionalize accesses based on whether or not it is nullptr.
1012 // Gather all GOT equivalent globals in the module. We really need two
1013 // passes over the globals: one to compute and another to avoid its emission
1014 // in EmitGlobalVariable, otherwise we would not be able to handle cases
1015 // where the got equivalent shows up before its use.
1016 computeGlobalGOTEquivs(M);
1018 // Emit global variables.
1019 for (const auto &G : M.globals())
1020 EmitGlobalVariable(&G);
1022 // Emit remaining GOT equivalent globals.
1023 emitGlobalGOTEquivs();
1025 // Emit visibility info for declarations
1026 for (const Function &F : M) {
1027 if (!F.isDeclaration())
1029 GlobalValue::VisibilityTypes V = F.getVisibility();
1030 if (V == GlobalValue::DefaultVisibility)
1033 MCSymbol *Name = getSymbol(&F);
1034 EmitVisibility(Name, V, false);
1037 const TargetLoweringObjectFile &TLOF = getObjFileLowering();
1039 // Emit module flags.
1040 SmallVector<Module::ModuleFlagEntry, 8> ModuleFlags;
1041 M.getModuleFlagsMetadata(ModuleFlags);
1042 if (!ModuleFlags.empty())
1043 TLOF.emitModuleFlags(*OutStreamer, ModuleFlags, *Mang, TM);
1045 if (TM.getTargetTriple().isOSBinFormatELF()) {
1046 MachineModuleInfoELF &MMIELF = MMI->getObjFileInfo<MachineModuleInfoELF>();
1048 // Output stubs for external and common global variables.
1049 MachineModuleInfoELF::SymbolListTy Stubs = MMIELF.GetGVStubList();
1050 if (!Stubs.empty()) {
1051 OutStreamer->SwitchSection(TLOF.getDataRelSection());
1052 const DataLayout *DL = TM.getDataLayout();
1054 for (const auto &Stub : Stubs) {
1055 OutStreamer->EmitLabel(Stub.first);
1056 OutStreamer->EmitSymbolValue(Stub.second.getPointer(),
1057 DL->getPointerSize());
1062 // Make sure we wrote out everything we need.
1063 OutStreamer->Flush();
1065 // Finalize debug and EH information.
1066 for (const HandlerInfo &HI : Handlers) {
1067 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName,
1068 TimePassesIsEnabled);
1069 HI.Handler->endModule();
1075 // If the target wants to know about weak references, print them all.
1076 if (MAI->getWeakRefDirective()) {
1077 // FIXME: This is not lazy, it would be nice to only print weak references
1078 // to stuff that is actually used. Note that doing so would require targets
1079 // to notice uses in operands (due to constant exprs etc). This should
1080 // happen with the MC stuff eventually.
1082 // Print out module-level global variables here.
1083 for (const auto &G : M.globals()) {
1084 if (!G.hasExternalWeakLinkage())
1086 OutStreamer->EmitSymbolAttribute(getSymbol(&G), MCSA_WeakReference);
1089 for (const auto &F : M) {
1090 if (!F.hasExternalWeakLinkage())
1092 OutStreamer->EmitSymbolAttribute(getSymbol(&F), MCSA_WeakReference);
1096 OutStreamer->AddBlankLine();
1097 for (const auto &Alias : M.aliases()) {
1098 MCSymbol *Name = getSymbol(&Alias);
1100 if (Alias.hasExternalLinkage() || !MAI->getWeakRefDirective())
1101 OutStreamer->EmitSymbolAttribute(Name, MCSA_Global);
1102 else if (Alias.hasWeakLinkage() || Alias.hasLinkOnceLinkage())
1103 OutStreamer->EmitSymbolAttribute(Name, MCSA_WeakReference);
1105 assert(Alias.hasLocalLinkage() && "Invalid alias linkage");
1107 EmitVisibility(Name, Alias.getVisibility());
1109 // Emit the directives as assignments aka .set:
1110 OutStreamer->EmitAssignment(Name, lowerConstant(Alias.getAliasee()));
1113 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
1114 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
1115 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
1116 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(**--I))
1117 MP->finishAssembly(M, *MI, *this);
1119 // Emit llvm.ident metadata in an '.ident' directive.
1120 EmitModuleIdents(M);
1122 // Emit __morestack address if needed for indirect calls.
1123 if (MMI->usesMorestackAddr()) {
1124 MCSection *ReadOnlySection =
1125 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly(),
1127 OutStreamer->SwitchSection(ReadOnlySection);
1129 MCSymbol *AddrSymbol =
1130 OutContext.getOrCreateSymbol(StringRef("__morestack_addr"));
1131 OutStreamer->EmitLabel(AddrSymbol);
1133 unsigned PtrSize = TM.getDataLayout()->getPointerSize(0);
1134 OutStreamer->EmitSymbolValue(GetExternalSymbolSymbol("__morestack"),
1138 // If we don't have any trampolines, then we don't require stack memory
1139 // to be executable. Some targets have a directive to declare this.
1140 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
1141 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
1142 if (MCSection *S = MAI->getNonexecutableStackSection(OutContext))
1143 OutStreamer->SwitchSection(S);
1145 // Allow the target to emit any magic that it wants at the end of the file,
1146 // after everything else has gone out.
1147 EmitEndOfAsmFile(M);
1149 delete Mang; Mang = nullptr;
1152 OutStreamer->Finish();
1153 OutStreamer->reset();
1158 MCSymbol *AsmPrinter::getCurExceptionSym() {
1159 if (!CurExceptionSym)
1160 CurExceptionSym = createTempSymbol("exception");
1161 return CurExceptionSym;
1164 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
1166 // Get the function symbol.
1167 CurrentFnSym = getSymbol(MF.getFunction());
1168 CurrentFnSymForSize = CurrentFnSym;
1169 CurrentFnBegin = nullptr;
1170 CurExceptionSym = nullptr;
1171 bool NeedsLocalForSize = MAI->needsLocalForSize();
1172 if (!MMI->getLandingPads().empty() || MMI->hasDebugInfo() ||
1173 NeedsLocalForSize) {
1174 CurrentFnBegin = createTempSymbol("func_begin");
1175 if (NeedsLocalForSize)
1176 CurrentFnSymForSize = CurrentFnBegin;
1180 LI = &getAnalysis<MachineLoopInfo>();
1184 // Keep track the alignment, constpool entries per Section.
1188 SmallVector<unsigned, 4> CPEs;
1189 SectionCPs(MCSection *s, unsigned a) : S(s), Alignment(a) {}
1193 /// EmitConstantPool - Print to the current output stream assembly
1194 /// representations of the constants in the constant pool MCP. This is
1195 /// used to print out constants which have been "spilled to memory" by
1196 /// the code generator.
1198 void AsmPrinter::EmitConstantPool() {
1199 const MachineConstantPool *MCP = MF->getConstantPool();
1200 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
1201 if (CP.empty()) return;
1203 // Calculate sections for constant pool entries. We collect entries to go into
1204 // the same section together to reduce amount of section switch statements.
1205 SmallVector<SectionCPs, 4> CPSections;
1206 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
1207 const MachineConstantPoolEntry &CPE = CP[i];
1208 unsigned Align = CPE.getAlignment();
1211 CPE.getSectionKind(TM.getDataLayout());
1213 const Constant *C = nullptr;
1214 if (!CPE.isMachineConstantPoolEntry())
1215 C = CPE.Val.ConstVal;
1217 MCSection *S = getObjFileLowering().getSectionForConstant(Kind, C);
1219 // The number of sections are small, just do a linear search from the
1220 // last section to the first.
1222 unsigned SecIdx = CPSections.size();
1223 while (SecIdx != 0) {
1224 if (CPSections[--SecIdx].S == S) {
1230 SecIdx = CPSections.size();
1231 CPSections.push_back(SectionCPs(S, Align));
1234 if (Align > CPSections[SecIdx].Alignment)
1235 CPSections[SecIdx].Alignment = Align;
1236 CPSections[SecIdx].CPEs.push_back(i);
1239 // Now print stuff into the calculated sections.
1240 const MCSection *CurSection = nullptr;
1241 unsigned Offset = 0;
1242 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
1243 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
1244 unsigned CPI = CPSections[i].CPEs[j];
1245 MCSymbol *Sym = GetCPISymbol(CPI);
1246 if (!Sym->isUndefined())
1249 if (CurSection != CPSections[i].S) {
1250 OutStreamer->SwitchSection(CPSections[i].S);
1251 EmitAlignment(Log2_32(CPSections[i].Alignment));
1252 CurSection = CPSections[i].S;
1256 MachineConstantPoolEntry CPE = CP[CPI];
1258 // Emit inter-object padding for alignment.
1259 unsigned AlignMask = CPE.getAlignment() - 1;
1260 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
1261 OutStreamer->EmitZeros(NewOffset - Offset);
1263 Type *Ty = CPE.getType();
1264 Offset = NewOffset +
1265 TM.getDataLayout()->getTypeAllocSize(Ty);
1267 OutStreamer->EmitLabel(Sym);
1268 if (CPE.isMachineConstantPoolEntry())
1269 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
1271 EmitGlobalConstant(CPE.Val.ConstVal);
1276 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
1277 /// by the current function to the current output stream.
1279 void AsmPrinter::EmitJumpTableInfo() {
1280 const DataLayout *DL = MF->getTarget().getDataLayout();
1281 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
1283 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
1284 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
1285 if (JT.empty()) return;
1287 // Pick the directive to use to print the jump table entries, and switch to
1288 // the appropriate section.
1289 const Function *F = MF->getFunction();
1290 const TargetLoweringObjectFile &TLOF = getObjFileLowering();
1291 bool JTInDiffSection = !TLOF.shouldPutJumpTableInFunctionSection(
1292 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32,
1294 if (JTInDiffSection) {
1295 // Drop it in the readonly section.
1296 MCSection *ReadOnlySection = TLOF.getSectionForJumpTable(*F, *Mang, TM);
1297 OutStreamer->SwitchSection(ReadOnlySection);
1300 EmitAlignment(Log2_32(
1301 MJTI->getEntryAlignment(*TM.getDataLayout())));
1303 // Jump tables in code sections are marked with a data_region directive
1304 // where that's supported.
1305 if (!JTInDiffSection)
1306 OutStreamer->EmitDataRegion(MCDR_DataRegionJT32);
1308 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
1309 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
1311 // If this jump table was deleted, ignore it.
1312 if (JTBBs.empty()) continue;
1314 // For the EK_LabelDifference32 entry, if using .set avoids a relocation,
1315 /// emit a .set directive for each unique entry.
1316 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
1317 MAI->doesSetDirectiveSuppressesReloc()) {
1318 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
1319 const TargetLowering *TLI = MF->getSubtarget().getTargetLowering();
1320 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
1321 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
1322 const MachineBasicBlock *MBB = JTBBs[ii];
1323 if (!EmittedSets.insert(MBB).second)
1326 // .set LJTSet, LBB32-base
1328 MCSymbolRefExpr::create(MBB->getSymbol(), OutContext);
1329 OutStreamer->EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
1330 MCBinaryExpr::createSub(LHS, Base,
1335 // On some targets (e.g. Darwin) we want to emit two consecutive labels
1336 // before each jump table. The first label is never referenced, but tells
1337 // the assembler and linker the extents of the jump table object. The
1338 // second label is actually referenced by the code.
1339 if (JTInDiffSection && DL->hasLinkerPrivateGlobalPrefix())
1340 // FIXME: This doesn't have to have any specific name, just any randomly
1341 // named and numbered 'l' label would work. Simplify GetJTISymbol.
1342 OutStreamer->EmitLabel(GetJTISymbol(JTI, true));
1344 OutStreamer->EmitLabel(GetJTISymbol(JTI));
1346 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
1347 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
1349 if (!JTInDiffSection)
1350 OutStreamer->EmitDataRegion(MCDR_DataRegionEnd);
1353 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
1355 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
1356 const MachineBasicBlock *MBB,
1357 unsigned UID) const {
1358 assert(MBB && MBB->getNumber() >= 0 && "Invalid basic block");
1359 const MCExpr *Value = nullptr;
1360 switch (MJTI->getEntryKind()) {
1361 case MachineJumpTableInfo::EK_Inline:
1362 llvm_unreachable("Cannot emit EK_Inline jump table entry");
1363 case MachineJumpTableInfo::EK_Custom32:
1364 Value = MF->getSubtarget().getTargetLowering()->LowerCustomJumpTableEntry(
1365 MJTI, MBB, UID, OutContext);
1367 case MachineJumpTableInfo::EK_BlockAddress:
1368 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
1370 Value = MCSymbolRefExpr::create(MBB->getSymbol(), OutContext);
1372 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
1373 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
1374 // with a relocation as gp-relative, e.g.:
1376 MCSymbol *MBBSym = MBB->getSymbol();
1377 OutStreamer->EmitGPRel32Value(MCSymbolRefExpr::create(MBBSym, OutContext));
1381 case MachineJumpTableInfo::EK_GPRel64BlockAddress: {
1382 // EK_GPRel64BlockAddress - Each entry is an address of block, encoded
1383 // with a relocation as gp-relative, e.g.:
1385 MCSymbol *MBBSym = MBB->getSymbol();
1386 OutStreamer->EmitGPRel64Value(MCSymbolRefExpr::create(MBBSym, OutContext));
1390 case MachineJumpTableInfo::EK_LabelDifference32: {
1391 // Each entry is the address of the block minus the address of the jump
1392 // table. This is used for PIC jump tables where gprel32 is not supported.
1394 // .word LBB123 - LJTI1_2
1395 // If the .set directive avoids relocations, this is emitted as:
1396 // .set L4_5_set_123, LBB123 - LJTI1_2
1397 // .word L4_5_set_123
1398 if (MAI->doesSetDirectiveSuppressesReloc()) {
1399 Value = MCSymbolRefExpr::create(GetJTSetSymbol(UID, MBB->getNumber()),
1403 Value = MCSymbolRefExpr::create(MBB->getSymbol(), OutContext);
1404 const TargetLowering *TLI = MF->getSubtarget().getTargetLowering();
1405 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF, UID, OutContext);
1406 Value = MCBinaryExpr::createSub(Value, Base, OutContext);
1411 assert(Value && "Unknown entry kind!");
1413 unsigned EntrySize =
1414 MJTI->getEntrySize(*TM.getDataLayout());
1415 OutStreamer->EmitValue(Value, EntrySize);
1419 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
1420 /// special global used by LLVM. If so, emit it and return true, otherwise
1421 /// do nothing and return false.
1422 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
1423 if (GV->getName() == "llvm.used") {
1424 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
1425 EmitLLVMUsedList(cast<ConstantArray>(GV->getInitializer()));
1429 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
1430 if (StringRef(GV->getSection()) == "llvm.metadata" ||
1431 GV->hasAvailableExternallyLinkage())
1434 if (!GV->hasAppendingLinkage()) return false;
1436 assert(GV->hasInitializer() && "Not a special LLVM global!");
1438 if (GV->getName() == "llvm.global_ctors") {
1439 EmitXXStructorList(GV->getInitializer(), /* isCtor */ true);
1441 if (TM.getRelocationModel() == Reloc::Static &&
1442 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1443 StringRef Sym(".constructors_used");
1444 OutStreamer->EmitSymbolAttribute(OutContext.getOrCreateSymbol(Sym),
1450 if (GV->getName() == "llvm.global_dtors") {
1451 EmitXXStructorList(GV->getInitializer(), /* isCtor */ false);
1453 if (TM.getRelocationModel() == Reloc::Static &&
1454 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1455 StringRef Sym(".destructors_used");
1456 OutStreamer->EmitSymbolAttribute(OutContext.getOrCreateSymbol(Sym),
1465 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
1466 /// global in the specified llvm.used list for which emitUsedDirectiveFor
1467 /// is true, as being used with this directive.
1468 void AsmPrinter::EmitLLVMUsedList(const ConstantArray *InitList) {
1469 // Should be an array of 'i8*'.
1470 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1471 const GlobalValue *GV =
1472 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
1474 OutStreamer->EmitSymbolAttribute(getSymbol(GV), MCSA_NoDeadStrip);
1480 Structor() : Priority(0), Func(nullptr), ComdatKey(nullptr) {}
1482 llvm::Constant *Func;
1483 llvm::GlobalValue *ComdatKey;
1487 /// EmitXXStructorList - Emit the ctor or dtor list taking into account the init
1489 void AsmPrinter::EmitXXStructorList(const Constant *List, bool isCtor) {
1490 // Should be an array of '{ int, void ()* }' structs. The first value is the
1492 if (!isa<ConstantArray>(List)) return;
1494 // Sanity check the structors list.
1495 const ConstantArray *InitList = dyn_cast<ConstantArray>(List);
1496 if (!InitList) return; // Not an array!
1497 StructType *ETy = dyn_cast<StructType>(InitList->getType()->getElementType());
1498 // FIXME: Only allow the 3-field form in LLVM 4.0.
1499 if (!ETy || ETy->getNumElements() < 2 || ETy->getNumElements() > 3)
1500 return; // Not an array of two or three elements!
1501 if (!isa<IntegerType>(ETy->getTypeAtIndex(0U)) ||
1502 !isa<PointerType>(ETy->getTypeAtIndex(1U))) return; // Not (int, ptr).
1503 if (ETy->getNumElements() == 3 && !isa<PointerType>(ETy->getTypeAtIndex(2U)))
1504 return; // Not (int, ptr, ptr).
1506 // Gather the structors in a form that's convenient for sorting by priority.
1507 SmallVector<Structor, 8> Structors;
1508 for (Value *O : InitList->operands()) {
1509 ConstantStruct *CS = dyn_cast<ConstantStruct>(O);
1510 if (!CS) continue; // Malformed.
1511 if (CS->getOperand(1)->isNullValue())
1512 break; // Found a null terminator, skip the rest.
1513 ConstantInt *Priority = dyn_cast<ConstantInt>(CS->getOperand(0));
1514 if (!Priority) continue; // Malformed.
1515 Structors.push_back(Structor());
1516 Structor &S = Structors.back();
1517 S.Priority = Priority->getLimitedValue(65535);
1518 S.Func = CS->getOperand(1);
1519 if (ETy->getNumElements() == 3 && !CS->getOperand(2)->isNullValue())
1520 S.ComdatKey = dyn_cast<GlobalValue>(CS->getOperand(2)->stripPointerCasts());
1523 // Emit the function pointers in the target-specific order
1524 const DataLayout *DL = TM.getDataLayout();
1525 unsigned Align = Log2_32(DL->getPointerPrefAlignment());
1526 std::stable_sort(Structors.begin(), Structors.end(),
1527 [](const Structor &L,
1528 const Structor &R) { return L.Priority < R.Priority; });
1529 for (Structor &S : Structors) {
1530 const TargetLoweringObjectFile &Obj = getObjFileLowering();
1531 const MCSymbol *KeySym = nullptr;
1532 if (GlobalValue *GV = S.ComdatKey) {
1533 if (GV->hasAvailableExternallyLinkage())
1534 // If the associated variable is available_externally, some other TU
1535 // will provide its dynamic initializer.
1538 KeySym = getSymbol(GV);
1540 MCSection *OutputSection =
1541 (isCtor ? Obj.getStaticCtorSection(S.Priority, KeySym)
1542 : Obj.getStaticDtorSection(S.Priority, KeySym));
1543 OutStreamer->SwitchSection(OutputSection);
1544 if (OutStreamer->getCurrentSection() != OutStreamer->getPreviousSection())
1545 EmitAlignment(Align);
1546 EmitXXStructor(S.Func);
1550 void AsmPrinter::EmitModuleIdents(Module &M) {
1551 if (!MAI->hasIdentDirective())
1554 if (const NamedMDNode *NMD = M.getNamedMetadata("llvm.ident")) {
1555 for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i) {
1556 const MDNode *N = NMD->getOperand(i);
1557 assert(N->getNumOperands() == 1 &&
1558 "llvm.ident metadata entry can have only one operand");
1559 const MDString *S = cast<MDString>(N->getOperand(0));
1560 OutStreamer->EmitIdent(S->getString());
1565 //===--------------------------------------------------------------------===//
1566 // Emission and print routines
1569 /// EmitInt8 - Emit a byte directive and value.
1571 void AsmPrinter::EmitInt8(int Value) const {
1572 OutStreamer->EmitIntValue(Value, 1);
1575 /// EmitInt16 - Emit a short directive and value.
1577 void AsmPrinter::EmitInt16(int Value) const {
1578 OutStreamer->EmitIntValue(Value, 2);
1581 /// EmitInt32 - Emit a long directive and value.
1583 void AsmPrinter::EmitInt32(int Value) const {
1584 OutStreamer->EmitIntValue(Value, 4);
1587 /// Emit something like ".long Hi-Lo" where the size in bytes of the directive
1588 /// is specified by Size and Hi/Lo specify the labels. This implicitly uses
1589 /// .set if it avoids relocations.
1590 void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
1591 unsigned Size) const {
1592 OutStreamer->emitAbsoluteSymbolDiff(Hi, Lo, Size);
1595 /// EmitLabelPlusOffset - Emit something like ".long Label+Offset"
1596 /// where the size in bytes of the directive is specified by Size and Label
1597 /// specifies the label. This implicitly uses .set if it is available.
1598 void AsmPrinter::EmitLabelPlusOffset(const MCSymbol *Label, uint64_t Offset,
1600 bool IsSectionRelative) const {
1601 if (MAI->needsDwarfSectionOffsetDirective() && IsSectionRelative) {
1602 OutStreamer->EmitCOFFSecRel32(Label);
1606 // Emit Label+Offset (or just Label if Offset is zero)
1607 const MCExpr *Expr = MCSymbolRefExpr::create(Label, OutContext);
1609 Expr = MCBinaryExpr::createAdd(
1610 Expr, MCConstantExpr::create(Offset, OutContext), OutContext);
1612 OutStreamer->EmitValue(Expr, Size);
1615 //===----------------------------------------------------------------------===//
1617 // EmitAlignment - Emit an alignment directive to the specified power of
1618 // two boundary. For example, if you pass in 3 here, you will get an 8
1619 // byte alignment. If a global value is specified, and if that global has
1620 // an explicit alignment requested, it will override the alignment request
1621 // if required for correctness.
1623 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalObject *GV) const {
1625 NumBits = getGVAlignmentLog2(GV, *TM.getDataLayout(),
1628 if (NumBits == 0) return; // 1-byte aligned: no need to emit alignment.
1631 static_cast<unsigned>(std::numeric_limits<unsigned>::digits) &&
1632 "undefined behavior");
1633 if (getCurrentSection()->getKind().isText())
1634 OutStreamer->EmitCodeAlignment(1u << NumBits);
1636 OutStreamer->EmitValueToAlignment(1u << NumBits);
1639 //===----------------------------------------------------------------------===//
1640 // Constant emission.
1641 //===----------------------------------------------------------------------===//
1643 const MCExpr *AsmPrinter::lowerConstant(const Constant *CV) {
1644 MCContext &Ctx = OutContext;
1646 if (CV->isNullValue() || isa<UndefValue>(CV))
1647 return MCConstantExpr::create(0, Ctx);
1649 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
1650 return MCConstantExpr::create(CI->getZExtValue(), Ctx);
1652 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
1653 return MCSymbolRefExpr::create(getSymbol(GV), Ctx);
1655 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
1656 return MCSymbolRefExpr::create(GetBlockAddressSymbol(BA), Ctx);
1658 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
1660 llvm_unreachable("Unknown constant value to lower!");
1663 if (const MCExpr *RelocExpr
1664 = getObjFileLowering().getExecutableRelativeSymbol(CE, *Mang, TM))
1667 switch (CE->getOpcode()) {
1669 // If the code isn't optimized, there may be outstanding folding
1670 // opportunities. Attempt to fold the expression using DataLayout as a
1671 // last resort before giving up.
1672 if (Constant *C = ConstantFoldConstantExpression(CE, *TM.getDataLayout()))
1674 return lowerConstant(C);
1676 // Otherwise report the problem to the user.
1679 raw_string_ostream OS(S);
1680 OS << "Unsupported expression in static initializer: ";
1681 CE->printAsOperand(OS, /*PrintType=*/false,
1682 !MF ? nullptr : MF->getFunction()->getParent());
1683 report_fatal_error(OS.str());
1685 case Instruction::GetElementPtr: {
1686 const DataLayout &DL = *TM.getDataLayout();
1688 // Generate a symbolic expression for the byte address
1689 APInt OffsetAI(DL.getPointerTypeSizeInBits(CE->getType()), 0);
1690 cast<GEPOperator>(CE)->accumulateConstantOffset(DL, OffsetAI);
1692 const MCExpr *Base = lowerConstant(CE->getOperand(0));
1696 int64_t Offset = OffsetAI.getSExtValue();
1697 return MCBinaryExpr::createAdd(Base, MCConstantExpr::create(Offset, Ctx),
1701 case Instruction::Trunc:
1702 // We emit the value and depend on the assembler to truncate the generated
1703 // expression properly. This is important for differences between
1704 // blockaddress labels. Since the two labels are in the same function, it
1705 // is reasonable to treat their delta as a 32-bit value.
1707 case Instruction::BitCast:
1708 return lowerConstant(CE->getOperand(0));
1710 case Instruction::IntToPtr: {
1711 const DataLayout &DL = *TM.getDataLayout();
1713 // Handle casts to pointers by changing them into casts to the appropriate
1714 // integer type. This promotes constant folding and simplifies this code.
1715 Constant *Op = CE->getOperand(0);
1716 Op = ConstantExpr::getIntegerCast(Op, DL.getIntPtrType(CV->getType()),
1718 return lowerConstant(Op);
1721 case Instruction::PtrToInt: {
1722 const DataLayout &DL = *TM.getDataLayout();
1724 // Support only foldable casts to/from pointers that can be eliminated by
1725 // changing the pointer to the appropriately sized integer type.
1726 Constant *Op = CE->getOperand(0);
1727 Type *Ty = CE->getType();
1729 const MCExpr *OpExpr = lowerConstant(Op);
1731 // We can emit the pointer value into this slot if the slot is an
1732 // integer slot equal to the size of the pointer.
1733 if (DL.getTypeAllocSize(Ty) == DL.getTypeAllocSize(Op->getType()))
1736 // Otherwise the pointer is smaller than the resultant integer, mask off
1737 // the high bits so we are sure to get a proper truncation if the input is
1739 unsigned InBits = DL.getTypeAllocSizeInBits(Op->getType());
1740 const MCExpr *MaskExpr = MCConstantExpr::create(~0ULL >> (64-InBits), Ctx);
1741 return MCBinaryExpr::createAnd(OpExpr, MaskExpr, Ctx);
1744 // The MC library also has a right-shift operator, but it isn't consistently
1745 // signed or unsigned between different targets.
1746 case Instruction::Add:
1747 case Instruction::Sub:
1748 case Instruction::Mul:
1749 case Instruction::SDiv:
1750 case Instruction::SRem:
1751 case Instruction::Shl:
1752 case Instruction::And:
1753 case Instruction::Or:
1754 case Instruction::Xor: {
1755 const MCExpr *LHS = lowerConstant(CE->getOperand(0));
1756 const MCExpr *RHS = lowerConstant(CE->getOperand(1));
1757 switch (CE->getOpcode()) {
1758 default: llvm_unreachable("Unknown binary operator constant cast expr");
1759 case Instruction::Add: return MCBinaryExpr::createAdd(LHS, RHS, Ctx);
1760 case Instruction::Sub: return MCBinaryExpr::createSub(LHS, RHS, Ctx);
1761 case Instruction::Mul: return MCBinaryExpr::createMul(LHS, RHS, Ctx);
1762 case Instruction::SDiv: return MCBinaryExpr::createDiv(LHS, RHS, Ctx);
1763 case Instruction::SRem: return MCBinaryExpr::createMod(LHS, RHS, Ctx);
1764 case Instruction::Shl: return MCBinaryExpr::createShl(LHS, RHS, Ctx);
1765 case Instruction::And: return MCBinaryExpr::createAnd(LHS, RHS, Ctx);
1766 case Instruction::Or: return MCBinaryExpr::createOr (LHS, RHS, Ctx);
1767 case Instruction::Xor: return MCBinaryExpr::createXor(LHS, RHS, Ctx);
1773 static void emitGlobalConstantImpl(const Constant *C, AsmPrinter &AP,
1774 const Constant *BaseCV = nullptr,
1775 uint64_t Offset = 0);
1777 /// isRepeatedByteSequence - Determine whether the given value is
1778 /// composed of a repeated sequence of identical bytes and return the
1779 /// byte value. If it is not a repeated sequence, return -1.
1780 static int isRepeatedByteSequence(const ConstantDataSequential *V) {
1781 StringRef Data = V->getRawDataValues();
1782 assert(!Data.empty() && "Empty aggregates should be CAZ node");
1784 for (unsigned i = 1, e = Data.size(); i != e; ++i)
1785 if (Data[i] != C) return -1;
1786 return static_cast<uint8_t>(C); // Ensure 255 is not returned as -1.
1790 /// isRepeatedByteSequence - Determine whether the given value is
1791 /// composed of a repeated sequence of identical bytes and return the
1792 /// byte value. If it is not a repeated sequence, return -1.
1793 static int isRepeatedByteSequence(const Value *V, TargetMachine &TM) {
1794 if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
1795 uint64_t Size = TM.getDataLayout()->getTypeAllocSizeInBits(V->getType());
1796 assert(Size % 8 == 0);
1798 // Extend the element to take zero padding into account.
1799 APInt Value = CI->getValue().zextOrSelf(Size);
1800 if (!Value.isSplat(8))
1803 return Value.zextOrTrunc(8).getZExtValue();
1805 if (const ConstantArray *CA = dyn_cast<ConstantArray>(V)) {
1806 // Make sure all array elements are sequences of the same repeated
1808 assert(CA->getNumOperands() != 0 && "Should be a CAZ");
1809 Constant *Op0 = CA->getOperand(0);
1810 int Byte = isRepeatedByteSequence(Op0, TM);
1814 // All array elements must be equal.
1815 for (unsigned i = 1, e = CA->getNumOperands(); i != e; ++i)
1816 if (CA->getOperand(i) != Op0)
1821 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(V))
1822 return isRepeatedByteSequence(CDS);
1827 static void emitGlobalConstantDataSequential(const ConstantDataSequential *CDS,
1830 // See if we can aggregate this into a .fill, if so, emit it as such.
1831 int Value = isRepeatedByteSequence(CDS, AP.TM);
1834 AP.TM.getDataLayout()->getTypeAllocSize(
1836 // Don't emit a 1-byte object as a .fill.
1838 return AP.OutStreamer->EmitFill(Bytes, Value);
1841 // If this can be emitted with .ascii/.asciz, emit it as such.
1842 if (CDS->isString())
1843 return AP.OutStreamer->EmitBytes(CDS->getAsString());
1845 // Otherwise, emit the values in successive locations.
1846 unsigned ElementByteSize = CDS->getElementByteSize();
1847 if (isa<IntegerType>(CDS->getElementType())) {
1848 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1850 AP.OutStreamer->GetCommentOS() << format("0x%" PRIx64 "\n",
1851 CDS->getElementAsInteger(i));
1852 AP.OutStreamer->EmitIntValue(CDS->getElementAsInteger(i),
1855 } else if (ElementByteSize == 4) {
1856 // FP Constants are printed as integer constants to avoid losing
1858 assert(CDS->getElementType()->isFloatTy());
1859 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1865 F = CDS->getElementAsFloat(i);
1867 AP.OutStreamer->GetCommentOS() << "float " << F << '\n';
1868 AP.OutStreamer->EmitIntValue(I, 4);
1871 assert(CDS->getElementType()->isDoubleTy());
1872 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1878 F = CDS->getElementAsDouble(i);
1880 AP.OutStreamer->GetCommentOS() << "double " << F << '\n';
1881 AP.OutStreamer->EmitIntValue(I, 8);
1885 const DataLayout &DL = *AP.TM.getDataLayout();
1886 unsigned Size = DL.getTypeAllocSize(CDS->getType());
1887 unsigned EmittedSize = DL.getTypeAllocSize(CDS->getType()->getElementType()) *
1888 CDS->getNumElements();
1889 if (unsigned Padding = Size - EmittedSize)
1890 AP.OutStreamer->EmitZeros(Padding);
1894 static void emitGlobalConstantArray(const ConstantArray *CA, AsmPrinter &AP,
1895 const Constant *BaseCV, uint64_t Offset) {
1896 // See if we can aggregate some values. Make sure it can be
1897 // represented as a series of bytes of the constant value.
1898 int Value = isRepeatedByteSequence(CA, AP.TM);
1899 const DataLayout &DL = *AP.TM.getDataLayout();
1902 uint64_t Bytes = DL.getTypeAllocSize(CA->getType());
1903 AP.OutStreamer->EmitFill(Bytes, Value);
1906 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i) {
1907 emitGlobalConstantImpl(CA->getOperand(i), AP, BaseCV, Offset);
1908 Offset += DL.getTypeAllocSize(CA->getOperand(i)->getType());
1913 static void emitGlobalConstantVector(const ConstantVector *CV, AsmPrinter &AP) {
1914 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1915 emitGlobalConstantImpl(CV->getOperand(i), AP);
1917 const DataLayout &DL = *AP.TM.getDataLayout();
1918 unsigned Size = DL.getTypeAllocSize(CV->getType());
1919 unsigned EmittedSize = DL.getTypeAllocSize(CV->getType()->getElementType()) *
1920 CV->getType()->getNumElements();
1921 if (unsigned Padding = Size - EmittedSize)
1922 AP.OutStreamer->EmitZeros(Padding);
1925 static void emitGlobalConstantStruct(const ConstantStruct *CS, AsmPrinter &AP,
1926 const Constant *BaseCV, uint64_t Offset) {
1927 // Print the fields in successive locations. Pad to align if needed!
1928 const DataLayout *DL = AP.TM.getDataLayout();
1929 unsigned Size = DL->getTypeAllocSize(CS->getType());
1930 const StructLayout *Layout = DL->getStructLayout(CS->getType());
1931 uint64_t SizeSoFar = 0;
1932 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1933 const Constant *Field = CS->getOperand(i);
1935 // Print the actual field value.
1936 emitGlobalConstantImpl(Field, AP, BaseCV, Offset+SizeSoFar);
1938 // Check if padding is needed and insert one or more 0s.
1939 uint64_t FieldSize = DL->getTypeAllocSize(Field->getType());
1940 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1941 - Layout->getElementOffset(i)) - FieldSize;
1942 SizeSoFar += FieldSize + PadSize;
1944 // Insert padding - this may include padding to increase the size of the
1945 // current field up to the ABI size (if the struct is not packed) as well
1946 // as padding to ensure that the next field starts at the right offset.
1947 AP.OutStreamer->EmitZeros(PadSize);
1949 assert(SizeSoFar == Layout->getSizeInBytes() &&
1950 "Layout of constant struct may be incorrect!");
1953 static void emitGlobalConstantFP(const ConstantFP *CFP, AsmPrinter &AP) {
1954 APInt API = CFP->getValueAPF().bitcastToAPInt();
1956 // First print a comment with what we think the original floating-point value
1957 // should have been.
1958 if (AP.isVerbose()) {
1959 SmallString<8> StrVal;
1960 CFP->getValueAPF().toString(StrVal);
1963 CFP->getType()->print(AP.OutStreamer->GetCommentOS());
1965 AP.OutStreamer->GetCommentOS() << "Printing <null> Type";
1966 AP.OutStreamer->GetCommentOS() << ' ' << StrVal << '\n';
1969 // Now iterate through the APInt chunks, emitting them in endian-correct
1970 // order, possibly with a smaller chunk at beginning/end (e.g. for x87 80-bit
1972 unsigned NumBytes = API.getBitWidth() / 8;
1973 unsigned TrailingBytes = NumBytes % sizeof(uint64_t);
1974 const uint64_t *p = API.getRawData();
1976 // PPC's long double has odd notions of endianness compared to how LLVM
1977 // handles it: p[0] goes first for *big* endian on PPC.
1978 if (AP.TM.getDataLayout()->isBigEndian() &&
1979 !CFP->getType()->isPPC_FP128Ty()) {
1980 int Chunk = API.getNumWords() - 1;
1983 AP.OutStreamer->EmitIntValue(p[Chunk--], TrailingBytes);
1985 for (; Chunk >= 0; --Chunk)
1986 AP.OutStreamer->EmitIntValue(p[Chunk], sizeof(uint64_t));
1989 for (Chunk = 0; Chunk < NumBytes / sizeof(uint64_t); ++Chunk)
1990 AP.OutStreamer->EmitIntValue(p[Chunk], sizeof(uint64_t));
1993 AP.OutStreamer->EmitIntValue(p[Chunk], TrailingBytes);
1996 // Emit the tail padding for the long double.
1997 const DataLayout &DL = *AP.TM.getDataLayout();
1998 AP.OutStreamer->EmitZeros(DL.getTypeAllocSize(CFP->getType()) -
1999 DL.getTypeStoreSize(CFP->getType()));
2002 static void emitGlobalConstantLargeInt(const ConstantInt *CI, AsmPrinter &AP) {
2003 const DataLayout *DL = AP.TM.getDataLayout();
2004 unsigned BitWidth = CI->getBitWidth();
2006 // Copy the value as we may massage the layout for constants whose bit width
2007 // is not a multiple of 64-bits.
2008 APInt Realigned(CI->getValue());
2009 uint64_t ExtraBits = 0;
2010 unsigned ExtraBitsSize = BitWidth & 63;
2012 if (ExtraBitsSize) {
2013 // The bit width of the data is not a multiple of 64-bits.
2014 // The extra bits are expected to be at the end of the chunk of the memory.
2016 // * Nothing to be done, just record the extra bits to emit.
2018 // * Record the extra bits to emit.
2019 // * Realign the raw data to emit the chunks of 64-bits.
2020 if (DL->isBigEndian()) {
2021 // Basically the structure of the raw data is a chunk of 64-bits cells:
2022 // 0 1 BitWidth / 64
2023 // [chunk1][chunk2] ... [chunkN].
2024 // The most significant chunk is chunkN and it should be emitted first.
2025 // However, due to the alignment issue chunkN contains useless bits.
2026 // Realign the chunks so that they contain only useless information:
2027 // ExtraBits 0 1 (BitWidth / 64) - 1
2028 // chu[nk1 chu][nk2 chu] ... [nkN-1 chunkN]
2029 ExtraBits = Realigned.getRawData()[0] &
2030 (((uint64_t)-1) >> (64 - ExtraBitsSize));
2031 Realigned = Realigned.lshr(ExtraBitsSize);
2033 ExtraBits = Realigned.getRawData()[BitWidth / 64];
2036 // We don't expect assemblers to support integer data directives
2037 // for more than 64 bits, so we emit the data in at most 64-bit
2038 // quantities at a time.
2039 const uint64_t *RawData = Realigned.getRawData();
2040 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
2041 uint64_t Val = DL->isBigEndian() ? RawData[e - i - 1] : RawData[i];
2042 AP.OutStreamer->EmitIntValue(Val, 8);
2045 if (ExtraBitsSize) {
2046 // Emit the extra bits after the 64-bits chunks.
2048 // Emit a directive that fills the expected size.
2049 uint64_t Size = AP.TM.getDataLayout()->getTypeAllocSize(
2051 Size -= (BitWidth / 64) * 8;
2052 assert(Size && Size * 8 >= ExtraBitsSize &&
2053 (ExtraBits & (((uint64_t)-1) >> (64 - ExtraBitsSize)))
2054 == ExtraBits && "Directive too small for extra bits.");
2055 AP.OutStreamer->EmitIntValue(ExtraBits, Size);
2059 /// \brief Transform a not absolute MCExpr containing a reference to a GOT
2060 /// equivalent global, by a target specific GOT pc relative access to the
2062 static void handleIndirectSymViaGOTPCRel(AsmPrinter &AP, const MCExpr **ME,
2063 const Constant *BaseCst,
2065 // The global @foo below illustrates a global that uses a got equivalent.
2067 // @bar = global i32 42
2068 // @gotequiv = private unnamed_addr constant i32* @bar
2069 // @foo = i32 trunc (i64 sub (i64 ptrtoint (i32** @gotequiv to i64),
2070 // i64 ptrtoint (i32* @foo to i64))
2073 // The cstexpr in @foo is converted into the MCExpr `ME`, where we actually
2074 // check whether @foo is suitable to use a GOTPCREL. `ME` is usually in the
2077 // foo = cstexpr, where
2078 // cstexpr := <gotequiv> - "." + <cst>
2079 // cstexpr := <gotequiv> - (<foo> - <offset from @foo base>) + <cst>
2081 // After canonicalization by evaluateAsRelocatable `ME` turns into:
2083 // cstexpr := <gotequiv> - <foo> + gotpcrelcst, where
2084 // gotpcrelcst := <offset from @foo base> + <cst>
2087 if (!(*ME)->evaluateAsRelocatable(MV, nullptr, nullptr) || MV.isAbsolute())
2089 const MCSymbolRefExpr *SymA = MV.getSymA();
2093 // Check that GOT equivalent symbol is cached.
2094 const MCSymbol *GOTEquivSym = &SymA->getSymbol();
2095 if (!AP.GlobalGOTEquivs.count(GOTEquivSym))
2098 const GlobalValue *BaseGV = dyn_cast<GlobalValue>(BaseCst);
2102 // Check for a valid base symbol
2103 const MCSymbol *BaseSym = AP.getSymbol(BaseGV);
2104 const MCSymbolRefExpr *SymB = MV.getSymB();
2106 if (!SymB || BaseSym != &SymB->getSymbol())
2109 // Make sure to match:
2111 // gotpcrelcst := <offset from @foo base> + <cst>
2113 // If gotpcrelcst is positive it means that we can safely fold the pc rel
2114 // displacement into the GOTPCREL. We can also can have an extra offset <cst>
2115 // if the target knows how to encode it.
2117 int64_t GOTPCRelCst = Offset + MV.getConstant();
2118 if (GOTPCRelCst < 0)
2120 if (!AP.getObjFileLowering().supportGOTPCRelWithOffset() && GOTPCRelCst != 0)
2123 // Emit the GOT PC relative to replace the got equivalent global, i.e.:
2130 // .long gotequiv - "." + <cst>
2132 // is replaced by the target specific equivalent to:
2137 // .long bar@GOTPCREL+<gotpcrelcst>
2139 AsmPrinter::GOTEquivUsePair Result = AP.GlobalGOTEquivs[GOTEquivSym];
2140 const GlobalVariable *GV = Result.first;
2141 int NumUses = (int)Result.second;
2142 const GlobalValue *FinalGV = dyn_cast<GlobalValue>(GV->getOperand(0));
2143 const MCSymbol *FinalSym = AP.getSymbol(FinalGV);
2144 *ME = AP.getObjFileLowering().getIndirectSymViaGOTPCRel(
2145 FinalSym, MV, Offset, AP.MMI, *AP.OutStreamer);
2147 // Update GOT equivalent usage information
2150 AP.GlobalGOTEquivs[GOTEquivSym] = std::make_pair(GV, NumUses);
2153 static void emitGlobalConstantImpl(const Constant *CV, AsmPrinter &AP,
2154 const Constant *BaseCV, uint64_t Offset) {
2155 const DataLayout *DL = AP.TM.getDataLayout();
2156 uint64_t Size = DL->getTypeAllocSize(CV->getType());
2158 // Globals with sub-elements such as combinations of arrays and structs
2159 // are handled recursively by emitGlobalConstantImpl. Keep track of the
2160 // constant symbol base and the current position with BaseCV and Offset.
2161 if (!BaseCV && CV->hasOneUse())
2162 BaseCV = dyn_cast<Constant>(CV->user_back());
2164 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV))
2165 return AP.OutStreamer->EmitZeros(Size);
2167 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
2174 AP.OutStreamer->GetCommentOS() << format("0x%" PRIx64 "\n",
2175 CI->getZExtValue());
2176 AP.OutStreamer->EmitIntValue(CI->getZExtValue(), Size);
2179 emitGlobalConstantLargeInt(CI, AP);
2184 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
2185 return emitGlobalConstantFP(CFP, AP);
2187 if (isa<ConstantPointerNull>(CV)) {
2188 AP.OutStreamer->EmitIntValue(0, Size);
2192 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(CV))
2193 return emitGlobalConstantDataSequential(CDS, AP);
2195 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
2196 return emitGlobalConstantArray(CVA, AP, BaseCV, Offset);
2198 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
2199 return emitGlobalConstantStruct(CVS, AP, BaseCV, Offset);
2201 if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
2202 // Look through bitcasts, which might not be able to be MCExpr'ized (e.g. of
2204 if (CE->getOpcode() == Instruction::BitCast)
2205 return emitGlobalConstantImpl(CE->getOperand(0), AP);
2208 // If the constant expression's size is greater than 64-bits, then we have
2209 // to emit the value in chunks. Try to constant fold the value and emit it
2211 Constant *New = ConstantFoldConstantExpression(CE, *DL);
2212 if (New && New != CE)
2213 return emitGlobalConstantImpl(New, AP);
2217 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
2218 return emitGlobalConstantVector(V, AP);
2220 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
2221 // thread the streamer with EmitValue.
2222 const MCExpr *ME = AP.lowerConstant(CV);
2224 // Since lowerConstant already folded and got rid of all IR pointer and
2225 // integer casts, detect GOT equivalent accesses by looking into the MCExpr
2227 if (AP.getObjFileLowering().supportIndirectSymViaGOTPCRel())
2228 handleIndirectSymViaGOTPCRel(AP, &ME, BaseCV, Offset);
2230 AP.OutStreamer->EmitValue(ME, Size);
2233 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
2234 void AsmPrinter::EmitGlobalConstant(const Constant *CV) {
2236 TM.getDataLayout()->getTypeAllocSize(CV->getType());
2238 emitGlobalConstantImpl(CV, *this);
2239 else if (MAI->hasSubsectionsViaSymbols()) {
2240 // If the global has zero size, emit a single byte so that two labels don't
2241 // look like they are at the same location.
2242 OutStreamer->EmitIntValue(0, 1);
2246 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
2247 // Target doesn't support this yet!
2248 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
2251 void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
2253 OS << '+' << Offset;
2254 else if (Offset < 0)
2258 //===----------------------------------------------------------------------===//
2259 // Symbol Lowering Routines.
2260 //===----------------------------------------------------------------------===//
2262 MCSymbol *AsmPrinter::createTempSymbol(const Twine &Name) const {
2263 return OutContext.createTempSymbol(Name, true);
2266 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
2267 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
2270 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
2271 return MMI->getAddrLabelSymbol(BB);
2274 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
2275 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
2276 const DataLayout *DL = TM.getDataLayout();
2277 return OutContext.getOrCreateSymbol
2278 (Twine(DL->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber())
2279 + "_" + Twine(CPID));
2282 /// GetJTISymbol - Return the symbol for the specified jump table entry.
2283 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
2284 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
2287 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
2288 /// FIXME: privatize to AsmPrinter.
2289 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
2290 const DataLayout *DL = TM.getDataLayout();
2291 return OutContext.getOrCreateSymbol
2292 (Twine(DL->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" +
2293 Twine(UID) + "_set_" + Twine(MBBID));
2296 MCSymbol *AsmPrinter::getSymbolWithGlobalValueBase(const GlobalValue *GV,
2297 StringRef Suffix) const {
2298 return getObjFileLowering().getSymbolWithGlobalValueBase(GV, Suffix, *Mang,
2302 /// Return the MCSymbol for the specified ExternalSymbol.
2303 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
2304 SmallString<60> NameStr;
2305 Mangler::getNameWithPrefix(NameStr, Sym, *TM.getDataLayout());
2306 return OutContext.getOrCreateSymbol(NameStr);
2311 /// PrintParentLoopComment - Print comments about parent loops of this one.
2312 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2313 unsigned FunctionNumber) {
2315 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
2316 OS.indent(Loop->getLoopDepth()*2)
2317 << "Parent Loop BB" << FunctionNumber << "_"
2318 << Loop->getHeader()->getNumber()
2319 << " Depth=" << Loop->getLoopDepth() << '\n';
2323 /// PrintChildLoopComment - Print comments about child loops within
2324 /// the loop for this basic block, with nesting.
2325 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2326 unsigned FunctionNumber) {
2327 // Add child loop information
2328 for (const MachineLoop *CL : *Loop) {
2329 OS.indent(CL->getLoopDepth()*2)
2330 << "Child Loop BB" << FunctionNumber << "_"
2331 << CL->getHeader()->getNumber() << " Depth " << CL->getLoopDepth()
2333 PrintChildLoopComment(OS, CL, FunctionNumber);
2337 /// emitBasicBlockLoopComments - Pretty-print comments for basic blocks.
2338 static void emitBasicBlockLoopComments(const MachineBasicBlock &MBB,
2339 const MachineLoopInfo *LI,
2340 const AsmPrinter &AP) {
2341 // Add loop depth information
2342 const MachineLoop *Loop = LI->getLoopFor(&MBB);
2345 MachineBasicBlock *Header = Loop->getHeader();
2346 assert(Header && "No header for loop");
2348 // If this block is not a loop header, just print out what is the loop header
2350 if (Header != &MBB) {
2351 AP.OutStreamer->AddComment(" in Loop: Header=BB" +
2352 Twine(AP.getFunctionNumber())+"_" +
2353 Twine(Loop->getHeader()->getNumber())+
2354 " Depth="+Twine(Loop->getLoopDepth()));
2358 // Otherwise, it is a loop header. Print out information about child and
2360 raw_ostream &OS = AP.OutStreamer->GetCommentOS();
2362 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
2365 OS.indent(Loop->getLoopDepth()*2-2);
2370 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
2372 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
2376 /// EmitBasicBlockStart - This method prints the label for the specified
2377 /// MachineBasicBlock, an alignment (if present) and a comment describing
2378 /// it if appropriate.
2379 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock &MBB) const {
2380 // Emit an alignment directive for this block, if needed.
2381 if (unsigned Align = MBB.getAlignment())
2382 EmitAlignment(Align);
2384 // If the block has its address taken, emit any labels that were used to
2385 // reference the block. It is possible that there is more than one label
2386 // here, because multiple LLVM BB's may have been RAUW'd to this block after
2387 // the references were generated.
2388 if (MBB.hasAddressTaken()) {
2389 const BasicBlock *BB = MBB.getBasicBlock();
2391 OutStreamer->AddComment("Block address taken");
2393 std::vector<MCSymbol*> Symbols = MMI->getAddrLabelSymbolToEmit(BB);
2394 for (auto *Sym : Symbols)
2395 OutStreamer->EmitLabel(Sym);
2398 // Print some verbose block comments.
2400 if (const BasicBlock *BB = MBB.getBasicBlock())
2402 OutStreamer->AddComment("%" + BB->getName());
2403 emitBasicBlockLoopComments(MBB, LI, *this);
2406 // Print the main label for the block.
2407 if (MBB.pred_empty() || isBlockOnlyReachableByFallthrough(&MBB)) {
2409 // NOTE: Want this comment at start of line, don't emit with AddComment.
2410 OutStreamer->emitRawComment(" BB#" + Twine(MBB.getNumber()) + ":", false);
2413 OutStreamer->EmitLabel(MBB.getSymbol());
2417 void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility,
2418 bool IsDefinition) const {
2419 MCSymbolAttr Attr = MCSA_Invalid;
2421 switch (Visibility) {
2423 case GlobalValue::HiddenVisibility:
2425 Attr = MAI->getHiddenVisibilityAttr();
2427 Attr = MAI->getHiddenDeclarationVisibilityAttr();
2429 case GlobalValue::ProtectedVisibility:
2430 Attr = MAI->getProtectedVisibilityAttr();
2434 if (Attr != MCSA_Invalid)
2435 OutStreamer->EmitSymbolAttribute(Sym, Attr);
2438 /// isBlockOnlyReachableByFallthough - Return true if the basic block has
2439 /// exactly one predecessor and the control transfer mechanism between
2440 /// the predecessor and this block is a fall-through.
2442 isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
2443 // If this is a landing pad, it isn't a fall through. If it has no preds,
2444 // then nothing falls through to it.
2445 if (MBB->isLandingPad() || MBB->pred_empty())
2448 // If there isn't exactly one predecessor, it can't be a fall through.
2449 if (MBB->pred_size() > 1)
2452 // The predecessor has to be immediately before this block.
2453 MachineBasicBlock *Pred = *MBB->pred_begin();
2454 if (!Pred->isLayoutSuccessor(MBB))
2457 // If the block is completely empty, then it definitely does fall through.
2461 // Check the terminators in the previous blocks
2462 for (const auto &MI : Pred->terminators()) {
2463 // If it is not a simple branch, we are in a table somewhere.
2464 if (!MI.isBranch() || MI.isIndirectBranch())
2467 // If we are the operands of one of the branches, this is not a fall
2468 // through. Note that targets with delay slots will usually bundle
2469 // terminators with the delay slot instruction.
2470 for (ConstMIBundleOperands OP(&MI); OP.isValid(); ++OP) {
2473 if (OP->isMBB() && OP->getMBB() == MBB)
2483 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy &S) {
2484 if (!S.usesMetadata())
2487 assert(!S.useStatepoints() && "statepoints do not currently support custom"
2488 " stackmap formats, please see the documentation for a description of"
2489 " the default format. If you really need a custom serialized format,"
2490 " please file a bug");
2492 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
2493 gcp_map_type::iterator GCPI = GCMap.find(&S);
2494 if (GCPI != GCMap.end())
2495 return GCPI->second.get();
2497 const char *Name = S.getName().c_str();
2499 for (GCMetadataPrinterRegistry::iterator
2500 I = GCMetadataPrinterRegistry::begin(),
2501 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
2502 if (strcmp(Name, I->getName()) == 0) {
2503 std::unique_ptr<GCMetadataPrinter> GMP = I->instantiate();
2505 auto IterBool = GCMap.insert(std::make_pair(&S, std::move(GMP)));
2506 return IterBool.first->second.get();
2509 report_fatal_error("no GCMetadataPrinter registered for GC: " + Twine(Name));
2512 /// Pin vtable to this file.
2513 AsmPrinterHandler::~AsmPrinterHandler() {}
2515 void AsmPrinterHandler::markFunctionEnd() {}