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 #define DEBUG_TYPE "asm-printer"
15 #include "llvm/CodeGen/AsmPrinter.h"
16 #include "DwarfDebug.h"
17 #include "DwarfException.h"
18 #include "llvm/Module.h"
19 #include "llvm/CodeGen/GCMetadataPrinter.h"
20 #include "llvm/CodeGen/MachineConstantPool.h"
21 #include "llvm/CodeGen/MachineFrameInfo.h"
22 #include "llvm/CodeGen/MachineFunction.h"
23 #include "llvm/CodeGen/MachineJumpTableInfo.h"
24 #include "llvm/CodeGen/MachineLoopInfo.h"
25 #include "llvm/CodeGen/MachineModuleInfo.h"
26 #include "llvm/Analysis/ConstantFolding.h"
27 #include "llvm/Analysis/DebugInfo.h"
28 #include "llvm/MC/MCAsmInfo.h"
29 #include "llvm/MC/MCContext.h"
30 #include "llvm/MC/MCExpr.h"
31 #include "llvm/MC/MCInst.h"
32 #include "llvm/MC/MCSection.h"
33 #include "llvm/MC/MCStreamer.h"
34 #include "llvm/MC/MCSymbol.h"
35 #include "llvm/Target/Mangler.h"
36 #include "llvm/Target/TargetData.h"
37 #include "llvm/Target/TargetInstrInfo.h"
38 #include "llvm/Target/TargetLowering.h"
39 #include "llvm/Target/TargetLoweringObjectFile.h"
40 #include "llvm/Target/TargetRegisterInfo.h"
41 #include "llvm/ADT/SmallString.h"
42 #include "llvm/ADT/Statistic.h"
43 #include "llvm/Support/ErrorHandling.h"
44 #include "llvm/Support/Format.h"
47 STATISTIC(EmittedInsts, "Number of machine instrs printed");
49 char AsmPrinter::ID = 0;
51 typedef DenseMap<GCStrategy*,GCMetadataPrinter*> gcp_map_type;
52 static gcp_map_type &getGCMap(void *&P) {
54 P = new gcp_map_type();
55 return *(gcp_map_type*)P;
59 AsmPrinter::AsmPrinter(TargetMachine &tm, MCStreamer &Streamer)
60 : MachineFunctionPass(&ID),
61 TM(tm), MAI(tm.getMCAsmInfo()),
62 OutContext(Streamer.getContext()),
63 OutStreamer(Streamer),
64 LastMI(0), LastFn(0), Counter(~0U), SetCounter(0) {
65 DD = 0; DE = 0; MMI = 0; LI = 0;
66 GCMetadataPrinters = 0;
67 VerboseAsm = Streamer.isVerboseAsm();
70 AsmPrinter::~AsmPrinter() {
71 assert(DD == 0 && DE == 0 && "Debug/EH info didn't get finalized");
73 if (GCMetadataPrinters != 0) {
74 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
76 for (gcp_map_type::iterator I = GCMap.begin(), E = GCMap.end(); I != E; ++I)
79 GCMetadataPrinters = 0;
85 /// getFunctionNumber - Return a unique ID for the current function.
87 unsigned AsmPrinter::getFunctionNumber() const {
88 return MF->getFunctionNumber();
91 TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
92 return TM.getTargetLowering()->getObjFileLowering();
96 /// getTargetData - Return information about data layout.
97 const TargetData &AsmPrinter::getTargetData() const {
98 return *TM.getTargetData();
101 /// getCurrentSection() - Return the current section we are emitting to.
102 const MCSection *AsmPrinter::getCurrentSection() const {
103 return OutStreamer.getCurrentSection();
108 void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
109 AU.setPreservesAll();
110 MachineFunctionPass::getAnalysisUsage(AU);
111 AU.addRequired<MachineModuleInfo>();
112 AU.addRequired<GCModuleInfo>();
114 AU.addRequired<MachineLoopInfo>();
117 bool AsmPrinter::doInitialization(Module &M) {
118 MMI = getAnalysisIfAvailable<MachineModuleInfo>();
119 MMI->AnalyzeModule(M);
121 // Initialize TargetLoweringObjectFile.
122 const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
123 .Initialize(OutContext, TM);
125 Mang = new Mangler(OutContext, *TM.getTargetData());
127 // Allow the target to emit any magic that it wants at the start of the file.
128 EmitStartOfAsmFile(M);
130 // Very minimal debug info. It is ignored if we emit actual debug info. If we
131 // don't, this at least helps the user find where a global came from.
132 if (MAI->hasSingleParameterDotFile()) {
134 OutStreamer.EmitFileDirective(M.getModuleIdentifier());
137 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
138 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
139 for (GCModuleInfo::iterator I = MI->begin(), E = MI->end(); I != E; ++I)
140 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
141 MP->beginAssembly(*this);
143 // Emit module-level inline asm if it exists.
144 if (!M.getModuleInlineAsm().empty()) {
145 OutStreamer.AddComment("Start of file scope inline assembly");
146 OutStreamer.AddBlankLine();
147 EmitInlineAsm(M.getModuleInlineAsm(), 0/*no loc cookie*/);
148 OutStreamer.AddComment("End of file scope inline assembly");
149 OutStreamer.AddBlankLine();
152 if (MAI->doesSupportDebugInformation())
153 DD = new DwarfDebug(this, &M);
155 if (MAI->doesSupportExceptionHandling())
156 DE = new DwarfException(this);
161 void AsmPrinter::EmitLinkage(unsigned Linkage, MCSymbol *GVSym) const {
162 switch ((GlobalValue::LinkageTypes)Linkage) {
163 case GlobalValue::CommonLinkage:
164 case GlobalValue::LinkOnceAnyLinkage:
165 case GlobalValue::LinkOnceODRLinkage:
166 case GlobalValue::WeakAnyLinkage:
167 case GlobalValue::WeakODRLinkage:
168 case GlobalValue::LinkerPrivateLinkage:
169 if (MAI->getWeakDefDirective() != 0) {
171 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
172 // .weak_definition _foo
173 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition);
174 } else if (const char *LinkOnce = MAI->getLinkOnceDirective()) {
176 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
177 // FIXME: linkonce should be a section attribute, handled by COFF Section
179 // http://sourceware.org/binutils/docs-2.20/as/Linkonce.html#Linkonce
181 // FIXME: It would be nice to use .linkonce samesize for non-common
183 OutStreamer.EmitRawText(StringRef(LinkOnce));
186 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak);
189 case GlobalValue::DLLExportLinkage:
190 case GlobalValue::AppendingLinkage:
191 // FIXME: appending linkage variables should go into a section of
192 // their name or something. For now, just emit them as external.
193 case GlobalValue::ExternalLinkage:
194 // If external or appending, declare as a global symbol.
196 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
198 case GlobalValue::PrivateLinkage:
199 case GlobalValue::InternalLinkage:
202 llvm_unreachable("Unknown linkage type!");
207 /// EmitGlobalVariable - Emit the specified global variable to the .s file.
208 void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
209 if (!GV->hasInitializer()) // External globals require no code.
212 // Check to see if this is a special global used by LLVM, if so, emit it.
213 if (EmitSpecialLLVMGlobal(GV))
216 MCSymbol *GVSym = Mang->getSymbol(GV);
217 EmitVisibility(GVSym, GV->getVisibility());
219 if (MAI->hasDotTypeDotSizeDirective())
220 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
222 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
224 const TargetData *TD = TM.getTargetData();
225 unsigned Size = TD->getTypeAllocSize(GV->getType()->getElementType());
226 unsigned AlignLog = TD->getPreferredAlignmentLog(GV);
228 // Handle common and BSS local symbols (.lcomm).
229 if (GVKind.isCommon() || GVKind.isBSSLocal()) {
230 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
233 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
234 /*PrintType=*/false, GV->getParent());
235 OutStreamer.GetCommentOS() << '\n';
238 // Handle common symbols.
239 if (GVKind.isCommon()) {
241 OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
245 // Handle local BSS symbols.
246 if (MAI->hasMachoZeroFillDirective()) {
247 const MCSection *TheSection =
248 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
249 // .zerofill __DATA, __bss, _foo, 400, 5
250 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
254 if (MAI->hasLCOMMDirective()) {
256 OutStreamer.EmitLocalCommonSymbol(GVSym, Size);
261 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local);
263 OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
267 const MCSection *TheSection =
268 getObjFileLowering().SectionForGlobal(GV, GVKind, Mang, TM);
270 // Handle the zerofill directive on darwin, which is a special form of BSS
272 if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) {
274 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
275 // .zerofill __DATA, __common, _foo, 400, 5
276 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
280 OutStreamer.SwitchSection(TheSection);
282 EmitLinkage(GV->getLinkage(), GVSym);
283 EmitAlignment(AlignLog, GV);
286 WriteAsOperand(OutStreamer.GetCommentOS(), GV,
287 /*PrintType=*/false, GV->getParent());
288 OutStreamer.GetCommentOS() << '\n';
290 OutStreamer.EmitLabel(GVSym);
292 EmitGlobalConstant(GV->getInitializer());
294 if (MAI->hasDotTypeDotSizeDirective())
296 OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext));
298 OutStreamer.AddBlankLine();
301 /// EmitFunctionHeader - This method emits the header for the current
303 void AsmPrinter::EmitFunctionHeader() {
304 // Print out constants referenced by the function
307 // Print the 'header' of function.
308 const Function *F = MF->getFunction();
310 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F, Mang, TM));
311 EmitVisibility(CurrentFnSym, F->getVisibility());
313 EmitLinkage(F->getLinkage(), CurrentFnSym);
314 EmitAlignment(MF->getAlignment(), F);
316 if (MAI->hasDotTypeDotSizeDirective())
317 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
320 WriteAsOperand(OutStreamer.GetCommentOS(), F,
321 /*PrintType=*/false, F->getParent());
322 OutStreamer.GetCommentOS() << '\n';
325 // Emit the CurrentFnSym. This is a virtual function to allow targets to
326 // do their wild and crazy things as required.
327 EmitFunctionEntryLabel();
329 // If the function had address-taken blocks that got deleted, then we have
330 // references to the dangling symbols. Emit them at the start of the function
331 // so that we don't get references to undefined symbols.
332 std::vector<MCSymbol*> DeadBlockSyms;
333 MMI->takeDeletedSymbolsForFunction(F, DeadBlockSyms);
334 for (unsigned i = 0, e = DeadBlockSyms.size(); i != e; ++i) {
335 OutStreamer.AddComment("Address taken block that was later removed");
336 OutStreamer.EmitLabel(DeadBlockSyms[i]);
339 // Add some workaround for linkonce linkage on Cygwin\MinGW.
340 if (MAI->getLinkOnceDirective() != 0 &&
341 (F->hasLinkOnceLinkage() || F->hasWeakLinkage())) {
342 // FIXME: What is this?
344 OutContext.GetOrCreateSymbol(Twine("Lllvm$workaround$fake$stub$")+
345 CurrentFnSym->getName());
346 OutStreamer.EmitLabel(FakeStub);
349 // Emit pre-function debug and/or EH information.
350 if (DE) DE->BeginFunction(MF);
351 if (DD) DD->beginFunction(MF);
354 /// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
355 /// function. This can be overridden by targets as required to do custom stuff.
356 void AsmPrinter::EmitFunctionEntryLabel() {
357 OutStreamer.EmitLabel(CurrentFnSym);
361 /// EmitComments - Pretty-print comments for instructions.
362 static void EmitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
363 const MachineFunction *MF = MI.getParent()->getParent();
364 const TargetMachine &TM = MF->getTarget();
366 DebugLoc DL = MI.getDebugLoc();
367 if (!DL.isUnknown()) { // Print source line info.
368 DIScope Scope(DL.getScope(MF->getFunction()->getContext()));
369 // Omit the directory, because it's likely to be long and uninteresting.
371 CommentOS << Scope.getFilename();
373 CommentOS << "<unknown>";
374 CommentOS << ':' << DL.getLine();
375 if (DL.getCol() != 0)
376 CommentOS << ':' << DL.getCol();
380 // Check for spills and reloads
383 const MachineFrameInfo *FrameInfo = MF->getFrameInfo();
385 // We assume a single instruction only has a spill or reload, not
387 const MachineMemOperand *MMO;
388 if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) {
389 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
390 MMO = *MI.memoperands_begin();
391 CommentOS << MMO->getSize() << "-byte Reload\n";
393 } else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) {
394 if (FrameInfo->isSpillSlotObjectIndex(FI))
395 CommentOS << MMO->getSize() << "-byte Folded Reload\n";
396 } else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) {
397 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
398 MMO = *MI.memoperands_begin();
399 CommentOS << MMO->getSize() << "-byte Spill\n";
401 } else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) {
402 if (FrameInfo->isSpillSlotObjectIndex(FI))
403 CommentOS << MMO->getSize() << "-byte Folded Spill\n";
406 // Check for spill-induced copies
407 unsigned SrcReg, DstReg, SrcSubIdx, DstSubIdx;
408 if (TM.getInstrInfo()->isMoveInstr(MI, SrcReg, DstReg,
409 SrcSubIdx, DstSubIdx)) {
410 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse))
411 CommentOS << " Reload Reuse\n";
415 /// EmitImplicitDef - This method emits the specified machine instruction
416 /// that is an implicit def.
417 static void EmitImplicitDef(const MachineInstr *MI, AsmPrinter &AP) {
418 unsigned RegNo = MI->getOperand(0).getReg();
419 AP.OutStreamer.AddComment(Twine("implicit-def: ") +
420 AP.TM.getRegisterInfo()->getName(RegNo));
421 AP.OutStreamer.AddBlankLine();
424 static void EmitKill(const MachineInstr *MI, AsmPrinter &AP) {
425 std::string Str = "kill:";
426 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
427 const MachineOperand &Op = MI->getOperand(i);
428 assert(Op.isReg() && "KILL instruction must have only register operands");
430 Str += AP.TM.getRegisterInfo()->getName(Op.getReg());
431 Str += (Op.isDef() ? "<def>" : "<kill>");
433 AP.OutStreamer.AddComment(Str);
434 AP.OutStreamer.AddBlankLine();
437 /// EmitDebugValueComment - This method handles the target-independent form
438 /// of DBG_VALUE, returning true if it was able to do so. A false return
439 /// means the target will need to handle MI in EmitInstruction.
440 static bool EmitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) {
442 std::string Str = "\t";
443 Str += AP.MAI->getCommentString();
444 Str += "DEBUG_VALUE: ";
445 // This code handles only the 3-operand target-independent form.
446 if (MI->getNumOperands() != 3)
449 // cast away const; DIetc do not take const operands for some reason.
450 DIVariable V((MDNode*)(MI->getOperand(2).getMetadata()));
454 // Register or immediate value. Register 0 means undef.
455 if (MI->getOperand(0).isFPImm()) {
456 APFloat APF = APFloat(MI->getOperand(0).getFPImm()->getValueAPF());
457 if (MI->getOperand(0).getFPImm()->getType()->isFloatTy()) {
458 sprintf(buf, "%e", APF.convertToFloat());
460 } else if (MI->getOperand(0).getFPImm()->getType()->isDoubleTy()) {
461 sprintf(buf, "%e", APF.convertToDouble());
464 // There is no good way to print long double. Convert a copy to
465 // double. Ah well, it's only a comment.
467 APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
469 Str += "(long double) ";
470 sprintf(buf, "%e", APF.convertToDouble());
473 } else if (MI->getOperand(0).isImm()) {
474 sprintf(buf, "%lld", MI->getOperand(0).getImm());
476 } else if (MI->getOperand(0).isReg()) {
477 if (MI->getOperand(0).getReg() == 0) {
478 // Suppress offset, it is not meaningful here.
480 // NOTE: Want this comment at start of line, don't emit with AddComment.
481 AP.OutStreamer.EmitRawText(Twine(Str));
484 Str += AP.TM.getRegisterInfo()->getName(MI->getOperand(0).getReg());
486 llvm_unreachable("Unknown operand type");
489 sprintf(buf, "%lld", MI->getOperand(1).getImm());
491 // NOTE: Want this comment at start of line, don't emit with AddComment.
492 AP.OutStreamer.EmitRawText(Twine(Str));
496 /// EmitFunctionBody - This method emits the body and trailer for a
498 void AsmPrinter::EmitFunctionBody() {
499 // Emit target-specific gunk before the function body.
500 EmitFunctionBodyStart();
502 bool ShouldPrintDebugScopes = DD && MMI->hasDebugInfo();
504 // Print out code for the function.
505 bool HasAnyRealCode = false;
506 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end();
508 // Print a label for the basic block.
509 EmitBasicBlockStart(I);
510 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
512 // Print the assembly for the instruction.
514 HasAnyRealCode = true;
518 if (ShouldPrintDebugScopes)
522 EmitComments(*II, OutStreamer.GetCommentOS());
524 switch (II->getOpcode()) {
525 case TargetOpcode::DBG_LABEL:
526 case TargetOpcode::EH_LABEL:
527 case TargetOpcode::GC_LABEL:
528 OutStreamer.EmitLabel(II->getOperand(0).getMCSymbol());
530 case TargetOpcode::INLINEASM:
533 case TargetOpcode::DBG_VALUE:
535 if (!EmitDebugValueComment(II, *this))
539 case TargetOpcode::IMPLICIT_DEF:
540 if (isVerbose()) EmitImplicitDef(II, *this);
542 case TargetOpcode::KILL:
543 if (isVerbose()) EmitKill(II, *this);
550 if (ShouldPrintDebugScopes)
555 // If the function is empty and the object file uses .subsections_via_symbols,
556 // then we need to emit *something* to the function body to prevent the
557 // labels from collapsing together. Just emit a 0 byte.
558 if (MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode)
559 OutStreamer.EmitIntValue(0, 1, 0/*addrspace*/);
561 // Emit target-specific gunk after the function body.
562 EmitFunctionBodyEnd();
564 // If the target wants a .size directive for the size of the function, emit
566 if (MAI->hasDotTypeDotSizeDirective()) {
567 // Create a symbol for the end of function, so we can get the size as
568 // difference between the function label and the temp label.
569 MCSymbol *FnEndLabel = OutContext.CreateTempSymbol();
570 OutStreamer.EmitLabel(FnEndLabel);
572 const MCExpr *SizeExp =
573 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(FnEndLabel, OutContext),
574 MCSymbolRefExpr::Create(CurrentFnSym, OutContext),
576 OutStreamer.EmitELFSize(CurrentFnSym, SizeExp);
579 // Emit post-function debug information.
580 if (DD) DD->endFunction(MF);
581 if (DE) DE->EndFunction();
584 // Print out jump tables referenced by the function.
587 OutStreamer.AddBlankLine();
591 bool AsmPrinter::doFinalization(Module &M) {
592 // Emit global variables.
593 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
595 EmitGlobalVariable(I);
597 // Finalize debug and EH information.
607 // If the target wants to know about weak references, print them all.
608 if (MAI->getWeakRefDirective()) {
609 // FIXME: This is not lazy, it would be nice to only print weak references
610 // to stuff that is actually used. Note that doing so would require targets
611 // to notice uses in operands (due to constant exprs etc). This should
612 // happen with the MC stuff eventually.
614 // Print out module-level global variables here.
615 for (Module::const_global_iterator I = M.global_begin(), E = M.global_end();
617 if (!I->hasExternalWeakLinkage()) continue;
618 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
621 for (Module::const_iterator I = M.begin(), E = M.end(); I != E; ++I) {
622 if (!I->hasExternalWeakLinkage()) continue;
623 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(I), MCSA_WeakReference);
627 if (MAI->hasSetDirective()) {
628 OutStreamer.AddBlankLine();
629 for (Module::const_alias_iterator I = M.alias_begin(), E = M.alias_end();
631 MCSymbol *Name = Mang->getSymbol(I);
633 const GlobalValue *GV = cast<GlobalValue>(I->getAliasedGlobal());
634 MCSymbol *Target = Mang->getSymbol(GV);
636 if (I->hasExternalLinkage() || !MAI->getWeakRefDirective())
637 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
638 else if (I->hasWeakLinkage())
639 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
641 assert(I->hasLocalLinkage() && "Invalid alias linkage");
643 EmitVisibility(Name, I->getVisibility());
645 // Emit the directives as assignments aka .set:
646 OutStreamer.EmitAssignment(Name,
647 MCSymbolRefExpr::Create(Target, OutContext));
651 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
652 assert(MI && "AsmPrinter didn't require GCModuleInfo?");
653 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
654 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*--I))
655 MP->finishAssembly(*this);
657 // If we don't have any trampolines, then we don't require stack memory
658 // to be executable. Some targets have a directive to declare this.
659 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
660 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
661 if (MCSection *S = MAI->getNonexecutableStackSection(OutContext))
662 OutStreamer.SwitchSection(S);
664 // Allow the target to emit any magic that it wants at the end of the file,
665 // after everything else has gone out.
668 delete Mang; Mang = 0;
671 OutStreamer.Finish();
675 void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
677 // Get the function symbol.
678 CurrentFnSym = Mang->getSymbol(MF.getFunction());
681 LI = &getAnalysis<MachineLoopInfo>();
685 // SectionCPs - Keep track the alignment, constpool entries per Section.
689 SmallVector<unsigned, 4> CPEs;
690 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
694 /// EmitConstantPool - Print to the current output stream assembly
695 /// representations of the constants in the constant pool MCP. This is
696 /// used to print out constants which have been "spilled to memory" by
697 /// the code generator.
699 void AsmPrinter::EmitConstantPool() {
700 const MachineConstantPool *MCP = MF->getConstantPool();
701 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
702 if (CP.empty()) return;
704 // Calculate sections for constant pool entries. We collect entries to go into
705 // the same section together to reduce amount of section switch statements.
706 SmallVector<SectionCPs, 4> CPSections;
707 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
708 const MachineConstantPoolEntry &CPE = CP[i];
709 unsigned Align = CPE.getAlignment();
712 switch (CPE.getRelocationInfo()) {
713 default: llvm_unreachable("Unknown section kind");
714 case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
716 Kind = SectionKind::getReadOnlyWithRelLocal();
719 switch (TM.getTargetData()->getTypeAllocSize(CPE.getType())) {
720 case 4: Kind = SectionKind::getMergeableConst4(); break;
721 case 8: Kind = SectionKind::getMergeableConst8(); break;
722 case 16: Kind = SectionKind::getMergeableConst16();break;
723 default: Kind = SectionKind::getMergeableConst(); break;
727 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
729 // The number of sections are small, just do a linear search from the
730 // last section to the first.
732 unsigned SecIdx = CPSections.size();
733 while (SecIdx != 0) {
734 if (CPSections[--SecIdx].S == S) {
740 SecIdx = CPSections.size();
741 CPSections.push_back(SectionCPs(S, Align));
744 if (Align > CPSections[SecIdx].Alignment)
745 CPSections[SecIdx].Alignment = Align;
746 CPSections[SecIdx].CPEs.push_back(i);
749 // Now print stuff into the calculated sections.
750 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
751 OutStreamer.SwitchSection(CPSections[i].S);
752 EmitAlignment(Log2_32(CPSections[i].Alignment));
755 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
756 unsigned CPI = CPSections[i].CPEs[j];
757 MachineConstantPoolEntry CPE = CP[CPI];
759 // Emit inter-object padding for alignment.
760 unsigned AlignMask = CPE.getAlignment() - 1;
761 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
762 OutStreamer.EmitFill(NewOffset - Offset, 0/*fillval*/, 0/*addrspace*/);
764 const Type *Ty = CPE.getType();
765 Offset = NewOffset + TM.getTargetData()->getTypeAllocSize(Ty);
767 // Emit the label with a comment on it.
769 OutStreamer.GetCommentOS() << "constant pool ";
770 WriteTypeSymbolic(OutStreamer.GetCommentOS(), CPE.getType(),
771 MF->getFunction()->getParent());
772 OutStreamer.GetCommentOS() << '\n';
774 OutStreamer.EmitLabel(GetCPISymbol(CPI));
776 if (CPE.isMachineConstantPoolEntry())
777 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
779 EmitGlobalConstant(CPE.Val.ConstVal);
784 /// EmitJumpTableInfo - Print assembly representations of the jump tables used
785 /// by the current function to the current output stream.
787 void AsmPrinter::EmitJumpTableInfo() {
788 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
789 if (MJTI == 0) return;
790 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
791 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
792 if (JT.empty()) return;
794 // Pick the directive to use to print the jump table entries, and switch to
795 // the appropriate section.
796 const Function *F = MF->getFunction();
797 bool JTInDiffSection = false;
798 if (// In PIC mode, we need to emit the jump table to the same section as the
799 // function body itself, otherwise the label differences won't make sense.
800 // FIXME: Need a better predicate for this: what about custom entries?
801 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
802 // We should also do if the section name is NULL or function is declared
803 // in discardable section
804 // FIXME: this isn't the right predicate, should be based on the MCSection
806 F->isWeakForLinker()) {
807 OutStreamer.SwitchSection(getObjFileLowering().SectionForGlobal(F,Mang,TM));
809 // Otherwise, drop it in the readonly section.
810 const MCSection *ReadOnlySection =
811 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
812 OutStreamer.SwitchSection(ReadOnlySection);
813 JTInDiffSection = true;
816 EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getTargetData())));
818 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
819 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
821 // If this jump table was deleted, ignore it.
822 if (JTBBs.empty()) continue;
824 // For the EK_LabelDifference32 entry, if the target supports .set, emit a
825 // .set directive for each unique entry. This reduces the number of
826 // relocations the assembler will generate for the jump table.
827 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
828 MAI->hasSetDirective()) {
829 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
830 const TargetLowering *TLI = TM.getTargetLowering();
831 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
832 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
833 const MachineBasicBlock *MBB = JTBBs[ii];
834 if (!EmittedSets.insert(MBB)) continue;
836 // .set LJTSet, LBB32-base
838 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
839 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
840 MCBinaryExpr::CreateSub(LHS, Base, OutContext));
844 // On some targets (e.g. Darwin) we want to emit two consequtive labels
845 // before each jump table. The first label is never referenced, but tells
846 // the assembler and linker the extents of the jump table object. The
847 // second label is actually referenced by the code.
848 if (JTInDiffSection && MAI->getLinkerPrivateGlobalPrefix()[0])
849 // FIXME: This doesn't have to have any specific name, just any randomly
850 // named and numbered 'l' label would work. Simplify GetJTISymbol.
851 OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
853 OutStreamer.EmitLabel(GetJTISymbol(JTI));
855 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
856 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
860 /// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
862 void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
863 const MachineBasicBlock *MBB,
864 unsigned UID) const {
865 const MCExpr *Value = 0;
866 switch (MJTI->getEntryKind()) {
867 case MachineJumpTableInfo::EK_Inline:
868 llvm_unreachable("Cannot emit EK_Inline jump table entry"); break;
869 case MachineJumpTableInfo::EK_Custom32:
870 Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID,
873 case MachineJumpTableInfo::EK_BlockAddress:
874 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
876 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
878 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
879 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
880 // with a relocation as gp-relative, e.g.:
882 MCSymbol *MBBSym = MBB->getSymbol();
883 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
887 case MachineJumpTableInfo::EK_LabelDifference32: {
888 // EK_LabelDifference32 - Each entry is the address of the block minus
889 // the address of the jump table. This is used for PIC jump tables where
890 // gprel32 is not supported. e.g.:
891 // .word LBB123 - LJTI1_2
892 // If the .set directive is supported, this is emitted as:
893 // .set L4_5_set_123, LBB123 - LJTI1_2
894 // .word L4_5_set_123
896 // If we have emitted set directives for the jump table entries, print
897 // them rather than the entries themselves. If we're emitting PIC, then
898 // emit the table entries as differences between two text section labels.
899 if (MAI->hasSetDirective()) {
900 // If we used .set, reference the .set's symbol.
901 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
905 // Otherwise, use the difference as the jump table entry.
906 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
907 const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext);
908 Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext);
913 assert(Value && "Unknown entry kind!");
915 unsigned EntrySize = MJTI->getEntrySize(*TM.getTargetData());
916 OutStreamer.EmitValue(Value, EntrySize, /*addrspace*/0);
920 /// EmitSpecialLLVMGlobal - Check to see if the specified global is a
921 /// special global used by LLVM. If so, emit it and return true, otherwise
922 /// do nothing and return false.
923 bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
924 if (GV->getName() == "llvm.used") {
925 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
926 EmitLLVMUsedList(GV->getInitializer());
930 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
931 if (GV->getSection() == "llvm.metadata" ||
932 GV->hasAvailableExternallyLinkage())
935 if (!GV->hasAppendingLinkage()) return false;
937 assert(GV->hasInitializer() && "Not a special LLVM global!");
939 const TargetData *TD = TM.getTargetData();
940 unsigned Align = Log2_32(TD->getPointerPrefAlignment());
941 if (GV->getName() == "llvm.global_ctors") {
942 OutStreamer.SwitchSection(getObjFileLowering().getStaticCtorSection());
943 EmitAlignment(Align, 0);
944 EmitXXStructorList(GV->getInitializer());
946 if (TM.getRelocationModel() == Reloc::Static &&
947 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
948 StringRef Sym(".constructors_used");
949 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
955 if (GV->getName() == "llvm.global_dtors") {
956 OutStreamer.SwitchSection(getObjFileLowering().getStaticDtorSection());
957 EmitAlignment(Align, 0);
958 EmitXXStructorList(GV->getInitializer());
960 if (TM.getRelocationModel() == Reloc::Static &&
961 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
962 StringRef Sym(".destructors_used");
963 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
972 /// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
973 /// global in the specified llvm.used list for which emitUsedDirectiveFor
974 /// is true, as being used with this directive.
975 void AsmPrinter::EmitLLVMUsedList(Constant *List) {
976 // Should be an array of 'i8*'.
977 ConstantArray *InitList = dyn_cast<ConstantArray>(List);
978 if (InitList == 0) return;
980 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
981 const GlobalValue *GV =
982 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
983 if (GV && getObjFileLowering().shouldEmitUsedDirectiveFor(GV, Mang))
984 OutStreamer.EmitSymbolAttribute(Mang->getSymbol(GV), MCSA_NoDeadStrip);
988 /// EmitXXStructorList - Emit the ctor or dtor list. This just prints out the
989 /// function pointers, ignoring the init priority.
990 void AsmPrinter::EmitXXStructorList(Constant *List) {
991 // Should be an array of '{ int, void ()* }' structs. The first value is the
992 // init priority, which we ignore.
993 if (!isa<ConstantArray>(List)) return;
994 ConstantArray *InitList = cast<ConstantArray>(List);
995 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i)
996 if (ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i))){
997 if (CS->getNumOperands() != 2) return; // Not array of 2-element structs.
999 if (CS->getOperand(1)->isNullValue())
1000 return; // Found a null terminator, exit printing.
1001 // Emit the function pointer.
1002 EmitGlobalConstant(CS->getOperand(1));
1006 //===--------------------------------------------------------------------===//
1007 // Emission and print routines
1010 /// EmitInt8 - Emit a byte directive and value.
1012 void AsmPrinter::EmitInt8(int Value) const {
1013 OutStreamer.EmitIntValue(Value, 1, 0/*addrspace*/);
1016 /// EmitInt16 - Emit a short directive and value.
1018 void AsmPrinter::EmitInt16(int Value) const {
1019 OutStreamer.EmitIntValue(Value, 2, 0/*addrspace*/);
1022 /// EmitInt32 - Emit a long directive and value.
1024 void AsmPrinter::EmitInt32(int Value) const {
1025 OutStreamer.EmitIntValue(Value, 4, 0/*addrspace*/);
1028 /// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size
1029 /// in bytes of the directive is specified by Size and Hi/Lo specify the
1030 /// labels. This implicitly uses .set if it is available.
1031 void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
1032 unsigned Size) const {
1033 // Get the Hi-Lo expression.
1034 const MCExpr *Diff =
1035 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext),
1036 MCSymbolRefExpr::Create(Lo, OutContext),
1039 if (!MAI->hasSetDirective()) {
1040 OutStreamer.EmitValue(Diff, Size, 0/*AddrSpace*/);
1044 // Otherwise, emit with .set (aka assignment).
1045 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1046 OutStreamer.EmitAssignment(SetLabel, Diff);
1047 OutStreamer.EmitSymbolValue(SetLabel, Size, 0/*AddrSpace*/);
1051 //===----------------------------------------------------------------------===//
1053 // EmitAlignment - Emit an alignment directive to the specified power of
1054 // two boundary. For example, if you pass in 3 here, you will get an 8
1055 // byte alignment. If a global value is specified, and if that global has
1056 // an explicit alignment requested, it will unconditionally override the
1057 // alignment request. However, if ForcedAlignBits is specified, this value
1058 // has final say: the ultimate alignment will be the max of ForcedAlignBits
1059 // and the alignment computed with NumBits and the global.
1061 // The algorithm is:
1063 // if (GV && GV->hasalignment) Align = GV->getalignment();
1064 // Align = std::max(Align, ForcedAlignBits);
1066 void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV,
1067 unsigned ForcedAlignBits,
1068 bool UseFillExpr) const {
1069 if (GV && GV->getAlignment())
1070 NumBits = Log2_32(GV->getAlignment());
1071 NumBits = std::max(NumBits, ForcedAlignBits);
1073 if (NumBits == 0) return; // No need to emit alignment.
1075 if (getCurrentSection()->getKind().isText())
1076 OutStreamer.EmitCodeAlignment(1 << NumBits);
1078 OutStreamer.EmitValueToAlignment(1 << NumBits, 0, 1, 0);
1081 /// LowerConstant - Lower the specified LLVM Constant to an MCExpr.
1083 static const MCExpr *LowerConstant(const Constant *CV, AsmPrinter &AP) {
1084 MCContext &Ctx = AP.OutContext;
1086 if (CV->isNullValue() || isa<UndefValue>(CV))
1087 return MCConstantExpr::Create(0, Ctx);
1089 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
1090 return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
1092 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
1093 return MCSymbolRefExpr::Create(AP.Mang->getSymbol(GV), Ctx);
1094 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
1095 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
1097 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
1099 llvm_unreachable("Unknown constant value to lower!");
1100 return MCConstantExpr::Create(0, Ctx);
1103 switch (CE->getOpcode()) {
1105 // If the code isn't optimized, there may be outstanding folding
1106 // opportunities. Attempt to fold the expression using TargetData as a
1107 // last resort before giving up.
1109 ConstantFoldConstantExpression(CE, AP.TM.getTargetData()))
1111 return LowerConstant(C, AP);
1115 llvm_unreachable("FIXME: Don't support this constant expr");
1116 case Instruction::GetElementPtr: {
1117 const TargetData &TD = *AP.TM.getTargetData();
1118 // Generate a symbolic expression for the byte address
1119 const Constant *PtrVal = CE->getOperand(0);
1120 SmallVector<Value*, 8> IdxVec(CE->op_begin()+1, CE->op_end());
1121 int64_t Offset = TD.getIndexedOffset(PtrVal->getType(), &IdxVec[0],
1124 const MCExpr *Base = LowerConstant(CE->getOperand(0), AP);
1128 // Truncate/sext the offset to the pointer size.
1129 if (TD.getPointerSizeInBits() != 64) {
1130 int SExtAmount = 64-TD.getPointerSizeInBits();
1131 Offset = (Offset << SExtAmount) >> SExtAmount;
1134 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
1138 case Instruction::Trunc:
1139 // We emit the value and depend on the assembler to truncate the generated
1140 // expression properly. This is important for differences between
1141 // blockaddress labels. Since the two labels are in the same function, it
1142 // is reasonable to treat their delta as a 32-bit value.
1144 case Instruction::BitCast:
1145 return LowerConstant(CE->getOperand(0), AP);
1147 case Instruction::IntToPtr: {
1148 const TargetData &TD = *AP.TM.getTargetData();
1149 // Handle casts to pointers by changing them into casts to the appropriate
1150 // integer type. This promotes constant folding and simplifies this code.
1151 Constant *Op = CE->getOperand(0);
1152 Op = ConstantExpr::getIntegerCast(Op, TD.getIntPtrType(CV->getContext()),
1154 return LowerConstant(Op, AP);
1157 case Instruction::PtrToInt: {
1158 const TargetData &TD = *AP.TM.getTargetData();
1159 // Support only foldable casts to/from pointers that can be eliminated by
1160 // changing the pointer to the appropriately sized integer type.
1161 Constant *Op = CE->getOperand(0);
1162 const Type *Ty = CE->getType();
1164 const MCExpr *OpExpr = LowerConstant(Op, AP);
1166 // We can emit the pointer value into this slot if the slot is an
1167 // integer slot equal to the size of the pointer.
1168 if (TD.getTypeAllocSize(Ty) == TD.getTypeAllocSize(Op->getType()))
1171 // Otherwise the pointer is smaller than the resultant integer, mask off
1172 // the high bits so we are sure to get a proper truncation if the input is
1174 unsigned InBits = TD.getTypeAllocSizeInBits(Op->getType());
1175 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
1176 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
1179 // The MC library also has a right-shift operator, but it isn't consistently
1180 // signed or unsigned between different targets.
1181 case Instruction::Add:
1182 case Instruction::Sub:
1183 case Instruction::Mul:
1184 case Instruction::SDiv:
1185 case Instruction::SRem:
1186 case Instruction::Shl:
1187 case Instruction::And:
1188 case Instruction::Or:
1189 case Instruction::Xor: {
1190 const MCExpr *LHS = LowerConstant(CE->getOperand(0), AP);
1191 const MCExpr *RHS = LowerConstant(CE->getOperand(1), AP);
1192 switch (CE->getOpcode()) {
1193 default: llvm_unreachable("Unknown binary operator constant cast expr");
1194 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
1195 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
1196 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx);
1197 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx);
1198 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx);
1199 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx);
1200 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
1201 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
1202 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
1208 static void EmitGlobalConstantArray(const ConstantArray *CA, unsigned AddrSpace,
1210 if (AddrSpace != 0 || !CA->isString()) {
1211 // Not a string. Print the values in successive locations
1212 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1213 AP.EmitGlobalConstant(CA->getOperand(i), AddrSpace);
1217 // Otherwise, it can be emitted as .ascii.
1218 SmallVector<char, 128> TmpVec;
1219 TmpVec.reserve(CA->getNumOperands());
1220 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1221 TmpVec.push_back(cast<ConstantInt>(CA->getOperand(i))->getZExtValue());
1223 AP.OutStreamer.EmitBytes(StringRef(TmpVec.data(), TmpVec.size()), AddrSpace);
1226 static void EmitGlobalConstantVector(const ConstantVector *CV,
1227 unsigned AddrSpace, AsmPrinter &AP) {
1228 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1229 AP.EmitGlobalConstant(CV->getOperand(i), AddrSpace);
1232 static void EmitGlobalConstantStruct(const ConstantStruct *CS,
1233 unsigned AddrSpace, AsmPrinter &AP) {
1234 // Print the fields in successive locations. Pad to align if needed!
1235 const TargetData *TD = AP.TM.getTargetData();
1236 unsigned Size = TD->getTypeAllocSize(CS->getType());
1237 const StructLayout *Layout = TD->getStructLayout(CS->getType());
1238 uint64_t SizeSoFar = 0;
1239 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1240 const Constant *Field = CS->getOperand(i);
1242 // Check if padding is needed and insert one or more 0s.
1243 uint64_t FieldSize = TD->getTypeAllocSize(Field->getType());
1244 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1245 - Layout->getElementOffset(i)) - FieldSize;
1246 SizeSoFar += FieldSize + PadSize;
1248 // Now print the actual field value.
1249 AP.EmitGlobalConstant(Field, AddrSpace);
1251 // Insert padding - this may include padding to increase the size of the
1252 // current field up to the ABI size (if the struct is not packed) as well
1253 // as padding to ensure that the next field starts at the right offset.
1254 AP.OutStreamer.EmitZeros(PadSize, AddrSpace);
1256 assert(SizeSoFar == Layout->getSizeInBytes() &&
1257 "Layout of constant struct may be incorrect!");
1260 static void EmitGlobalConstantUnion(const ConstantUnion *CU,
1261 unsigned AddrSpace, AsmPrinter &AP) {
1262 const TargetData *TD = AP.TM.getTargetData();
1263 unsigned Size = TD->getTypeAllocSize(CU->getType());
1265 const Constant *Contents = CU->getOperand(0);
1266 unsigned FilledSize = TD->getTypeAllocSize(Contents->getType());
1268 // Print the actually filled part
1269 AP.EmitGlobalConstant(Contents, AddrSpace);
1271 // And pad with enough zeroes
1272 AP.OutStreamer.EmitZeros(Size-FilledSize, AddrSpace);
1275 static void EmitGlobalConstantFP(const ConstantFP *CFP, unsigned AddrSpace,
1277 // FP Constants are printed as integer constants to avoid losing
1279 if (CFP->getType()->isDoubleTy()) {
1280 if (AP.isVerbose()) {
1281 double Val = CFP->getValueAPF().convertToDouble();
1282 AP.OutStreamer.GetCommentOS() << "double " << Val << '\n';
1285 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1286 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1290 if (CFP->getType()->isFloatTy()) {
1291 if (AP.isVerbose()) {
1292 float Val = CFP->getValueAPF().convertToFloat();
1293 AP.OutStreamer.GetCommentOS() << "float " << Val << '\n';
1295 uint64_t Val = CFP->getValueAPF().bitcastToAPInt().getZExtValue();
1296 AP.OutStreamer.EmitIntValue(Val, 4, AddrSpace);
1300 if (CFP->getType()->isX86_FP80Ty()) {
1301 // all long double variants are printed as hex
1302 // API needed to prevent premature destruction
1303 APInt API = CFP->getValueAPF().bitcastToAPInt();
1304 const uint64_t *p = API.getRawData();
1305 if (AP.isVerbose()) {
1306 // Convert to double so we can print the approximate val as a comment.
1307 APFloat DoubleVal = CFP->getValueAPF();
1309 DoubleVal.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
1311 AP.OutStreamer.GetCommentOS() << "x86_fp80 ~= "
1312 << DoubleVal.convertToDouble() << '\n';
1315 if (AP.TM.getTargetData()->isBigEndian()) {
1316 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1317 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1319 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1320 AP.OutStreamer.EmitIntValue(p[1], 2, AddrSpace);
1323 // Emit the tail padding for the long double.
1324 const TargetData &TD = *AP.TM.getTargetData();
1325 AP.OutStreamer.EmitZeros(TD.getTypeAllocSize(CFP->getType()) -
1326 TD.getTypeStoreSize(CFP->getType()), AddrSpace);
1330 assert(CFP->getType()->isPPC_FP128Ty() &&
1331 "Floating point constant type not handled");
1332 // All long double variants are printed as hex
1333 // API needed to prevent premature destruction.
1334 APInt API = CFP->getValueAPF().bitcastToAPInt();
1335 const uint64_t *p = API.getRawData();
1336 if (AP.TM.getTargetData()->isBigEndian()) {
1337 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1338 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1340 AP.OutStreamer.EmitIntValue(p[1], 8, AddrSpace);
1341 AP.OutStreamer.EmitIntValue(p[0], 8, AddrSpace);
1345 static void EmitGlobalConstantLargeInt(const ConstantInt *CI,
1346 unsigned AddrSpace, AsmPrinter &AP) {
1347 const TargetData *TD = AP.TM.getTargetData();
1348 unsigned BitWidth = CI->getBitWidth();
1349 assert((BitWidth & 63) == 0 && "only support multiples of 64-bits");
1351 // We don't expect assemblers to support integer data directives
1352 // for more than 64 bits, so we emit the data in at most 64-bit
1353 // quantities at a time.
1354 const uint64_t *RawData = CI->getValue().getRawData();
1355 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1356 uint64_t Val = TD->isBigEndian() ? RawData[e - i - 1] : RawData[i];
1357 AP.OutStreamer.EmitIntValue(Val, 8, AddrSpace);
1361 /// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1362 void AsmPrinter::EmitGlobalConstant(const Constant *CV, unsigned AddrSpace) {
1363 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV)) {
1364 uint64_t Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1365 if (Size == 0) Size = 1; // An empty "_foo:" followed by a section is undef.
1366 return OutStreamer.EmitZeros(Size, AddrSpace);
1369 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1370 unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1377 OutStreamer.GetCommentOS() << format("0x%llx\n", CI->getZExtValue());
1378 OutStreamer.EmitIntValue(CI->getZExtValue(), Size, AddrSpace);
1381 EmitGlobalConstantLargeInt(CI, AddrSpace, *this);
1386 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
1387 return EmitGlobalConstantArray(CVA, AddrSpace, *this);
1389 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
1390 return EmitGlobalConstantStruct(CVS, AddrSpace, *this);
1392 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
1393 return EmitGlobalConstantFP(CFP, AddrSpace, *this);
1395 if (isa<ConstantPointerNull>(CV)) {
1396 unsigned Size = TM.getTargetData()->getTypeAllocSize(CV->getType());
1397 OutStreamer.EmitIntValue(0, Size, AddrSpace);
1401 if (const ConstantUnion *CVU = dyn_cast<ConstantUnion>(CV))
1402 return EmitGlobalConstantUnion(CVU, AddrSpace, *this);
1404 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
1405 return EmitGlobalConstantVector(V, AddrSpace, *this);
1407 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
1408 // thread the streamer with EmitValue.
1409 OutStreamer.EmitValue(LowerConstant(CV, *this),
1410 TM.getTargetData()->getTypeAllocSize(CV->getType()),
1414 void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
1415 // Target doesn't support this yet!
1416 llvm_unreachable("Target does not support EmitMachineConstantPoolValue");
1419 void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
1421 OS << '+' << Offset;
1422 else if (Offset < 0)
1426 //===----------------------------------------------------------------------===//
1427 // Symbol Lowering Routines.
1428 //===----------------------------------------------------------------------===//
1430 /// GetTempSymbol - Return the MCSymbol corresponding to the assembler
1431 /// temporary label with the specified stem and unique ID.
1432 MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name, unsigned ID) const {
1433 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix()) +
1437 /// GetTempSymbol - Return an assembler temporary label with the specified
1439 MCSymbol *AsmPrinter::GetTempSymbol(StringRef Name) const {
1440 return OutContext.GetOrCreateSymbol(Twine(MAI->getPrivateGlobalPrefix())+
1445 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
1446 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
1449 MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
1450 return MMI->getAddrLabelSymbol(BB);
1453 /// GetCPISymbol - Return the symbol for the specified constant pool entry.
1454 MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
1455 return OutContext.GetOrCreateSymbol
1456 (Twine(MAI->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber())
1457 + "_" + Twine(CPID));
1460 /// GetJTISymbol - Return the symbol for the specified jump table entry.
1461 MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
1462 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
1465 /// GetJTSetSymbol - Return the symbol for the specified jump table .set
1466 /// FIXME: privatize to AsmPrinter.
1467 MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
1468 return OutContext.GetOrCreateSymbol
1469 (Twine(MAI->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" +
1470 Twine(UID) + "_set_" + Twine(MBBID));
1473 /// GetSymbolWithGlobalValueBase - Return the MCSymbol for a symbol with
1474 /// global value name as its base, with the specified suffix, and where the
1475 /// symbol is forced to have private linkage if ForcePrivate is true.
1476 MCSymbol *AsmPrinter::GetSymbolWithGlobalValueBase(const GlobalValue *GV,
1478 bool ForcePrivate) const {
1479 SmallString<60> NameStr;
1480 Mang->getNameWithPrefix(NameStr, GV, ForcePrivate);
1481 NameStr.append(Suffix.begin(), Suffix.end());
1482 return OutContext.GetOrCreateSymbol(NameStr.str());
1485 /// GetExternalSymbolSymbol - Return the MCSymbol for the specified
1487 MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
1488 SmallString<60> NameStr;
1489 Mang->getNameWithPrefix(NameStr, Sym);
1490 return OutContext.GetOrCreateSymbol(NameStr.str());
1495 /// PrintParentLoopComment - Print comments about parent loops of this one.
1496 static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1497 unsigned FunctionNumber) {
1498 if (Loop == 0) return;
1499 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
1500 OS.indent(Loop->getLoopDepth()*2)
1501 << "Parent Loop BB" << FunctionNumber << "_"
1502 << Loop->getHeader()->getNumber()
1503 << " Depth=" << Loop->getLoopDepth() << '\n';
1507 /// PrintChildLoopComment - Print comments about child loops within
1508 /// the loop for this basic block, with nesting.
1509 static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
1510 unsigned FunctionNumber) {
1511 // Add child loop information
1512 for (MachineLoop::iterator CL = Loop->begin(), E = Loop->end();CL != E; ++CL){
1513 OS.indent((*CL)->getLoopDepth()*2)
1514 << "Child Loop BB" << FunctionNumber << "_"
1515 << (*CL)->getHeader()->getNumber() << " Depth " << (*CL)->getLoopDepth()
1517 PrintChildLoopComment(OS, *CL, FunctionNumber);
1521 /// EmitBasicBlockLoopComments - Pretty-print comments for basic blocks.
1522 static void EmitBasicBlockLoopComments(const MachineBasicBlock &MBB,
1523 const MachineLoopInfo *LI,
1524 const AsmPrinter &AP) {
1525 // Add loop depth information
1526 const MachineLoop *Loop = LI->getLoopFor(&MBB);
1527 if (Loop == 0) return;
1529 MachineBasicBlock *Header = Loop->getHeader();
1530 assert(Header && "No header for loop");
1532 // If this block is not a loop header, just print out what is the loop header
1534 if (Header != &MBB) {
1535 AP.OutStreamer.AddComment(" in Loop: Header=BB" +
1536 Twine(AP.getFunctionNumber())+"_" +
1537 Twine(Loop->getHeader()->getNumber())+
1538 " Depth="+Twine(Loop->getLoopDepth()));
1542 // Otherwise, it is a loop header. Print out information about child and
1544 raw_ostream &OS = AP.OutStreamer.GetCommentOS();
1546 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
1549 OS.indent(Loop->getLoopDepth()*2-2);
1554 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
1556 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
1560 /// EmitBasicBlockStart - This method prints the label for the specified
1561 /// MachineBasicBlock, an alignment (if present) and a comment describing
1562 /// it if appropriate.
1563 void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock *MBB) const {
1564 // Emit an alignment directive for this block, if needed.
1565 if (unsigned Align = MBB->getAlignment())
1566 EmitAlignment(Log2_32(Align));
1568 // If the block has its address taken, emit any labels that were used to
1569 // reference the block. It is possible that there is more than one label
1570 // here, because multiple LLVM BB's may have been RAUW'd to this block after
1571 // the references were generated.
1572 if (MBB->hasAddressTaken()) {
1573 const BasicBlock *BB = MBB->getBasicBlock();
1575 OutStreamer.AddComment("Block address taken");
1577 std::vector<MCSymbol*> Syms = MMI->getAddrLabelSymbolToEmit(BB);
1579 for (unsigned i = 0, e = Syms.size(); i != e; ++i)
1580 OutStreamer.EmitLabel(Syms[i]);
1583 // Print the main label for the block.
1584 if (MBB->pred_empty() || isBlockOnlyReachableByFallthrough(MBB)) {
1585 if (isVerbose() && OutStreamer.hasRawTextSupport()) {
1586 if (const BasicBlock *BB = MBB->getBasicBlock())
1588 OutStreamer.AddComment("%" + BB->getName());
1590 EmitBasicBlockLoopComments(*MBB, LI, *this);
1592 // NOTE: Want this comment at start of line, don't emit with AddComment.
1593 OutStreamer.EmitRawText(Twine(MAI->getCommentString()) + " BB#" +
1594 Twine(MBB->getNumber()) + ":");
1598 if (const BasicBlock *BB = MBB->getBasicBlock())
1600 OutStreamer.AddComment("%" + BB->getName());
1601 EmitBasicBlockLoopComments(*MBB, LI, *this);
1604 OutStreamer.EmitLabel(MBB->getSymbol());
1608 void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility) const {
1609 MCSymbolAttr Attr = MCSA_Invalid;
1611 switch (Visibility) {
1613 case GlobalValue::HiddenVisibility:
1614 Attr = MAI->getHiddenVisibilityAttr();
1616 case GlobalValue::ProtectedVisibility:
1617 Attr = MAI->getProtectedVisibilityAttr();
1621 if (Attr != MCSA_Invalid)
1622 OutStreamer.EmitSymbolAttribute(Sym, Attr);
1625 /// isBlockOnlyReachableByFallthough - Return true if the basic block has
1626 /// exactly one predecessor and the control transfer mechanism between
1627 /// the predecessor and this block is a fall-through.
1629 isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
1630 // If this is a landing pad, it isn't a fall through. If it has no preds,
1631 // then nothing falls through to it.
1632 if (MBB->isLandingPad() || MBB->pred_empty())
1635 // If there isn't exactly one predecessor, it can't be a fall through.
1636 MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(), PI2 = PI;
1638 if (PI2 != MBB->pred_end())
1641 // The predecessor has to be immediately before this block.
1642 const MachineBasicBlock *Pred = *PI;
1644 if (!Pred->isLayoutSuccessor(MBB))
1647 // If the block is completely empty, then it definitely does fall through.
1651 // Otherwise, check the last instruction.
1652 const MachineInstr &LastInst = Pred->back();
1653 return !LastInst.getDesc().isBarrier();
1658 GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy *S) {
1659 if (!S->usesMetadata())
1662 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
1663 gcp_map_type::iterator GCPI = GCMap.find(S);
1664 if (GCPI != GCMap.end())
1665 return GCPI->second;
1667 const char *Name = S->getName().c_str();
1669 for (GCMetadataPrinterRegistry::iterator
1670 I = GCMetadataPrinterRegistry::begin(),
1671 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
1672 if (strcmp(Name, I->getName()) == 0) {
1673 GCMetadataPrinter *GMP = I->instantiate();
1675 GCMap.insert(std::make_pair(S, GMP));
1679 llvm_report_error("no GCMetadataPrinter registered for GC: " + Twine(Name));