Bug Summary

File:lib/CodeGen/AsmPrinter/AsmPrinter.cpp
Location:line 1498, column 40
Description:The result of the '<<' expression is undefined

Annotated Source Code

1//===-- AsmPrinter.cpp - Common AsmPrinter code ---------------------------===//
2//
3// The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file implements the AsmPrinter class.
11//
12//===----------------------------------------------------------------------===//
13
14#include "llvm/CodeGen/AsmPrinter.h"
15#include "DwarfDebug.h"
16#include "DwarfException.h"
17#include "Win64Exception.h"
18#include "WinCodeViewLineTables.h"
19#include "llvm/ADT/SmallString.h"
20#include "llvm/ADT/Statistic.h"
21#include "llvm/Analysis/ConstantFolding.h"
22#include "llvm/Analysis/JumpInstrTableInfo.h"
23#include "llvm/CodeGen/Analysis.h"
24#include "llvm/CodeGen/GCMetadataPrinter.h"
25#include "llvm/CodeGen/MachineConstantPool.h"
26#include "llvm/CodeGen/MachineFrameInfo.h"
27#include "llvm/CodeGen/MachineFunction.h"
28#include "llvm/CodeGen/MachineInstrBundle.h"
29#include "llvm/CodeGen/MachineJumpTableInfo.h"
30#include "llvm/CodeGen/MachineLoopInfo.h"
31#include "llvm/CodeGen/MachineModuleInfo.h"
32#include "llvm/IR/DataLayout.h"
33#include "llvm/IR/DebugInfo.h"
34#include "llvm/IR/Mangler.h"
35#include "llvm/IR/Module.h"
36#include "llvm/IR/Operator.h"
37#include "llvm/MC/MCAsmInfo.h"
38#include "llvm/MC/MCContext.h"
39#include "llvm/MC/MCExpr.h"
40#include "llvm/MC/MCInst.h"
41#include "llvm/MC/MCSection.h"
42#include "llvm/MC/MCStreamer.h"
43#include "llvm/MC/MCSymbol.h"
44#include "llvm/Support/ErrorHandling.h"
45#include "llvm/Support/Format.h"
46#include "llvm/Support/MathExtras.h"
47#include "llvm/Support/Timer.h"
48#include "llvm/Target/TargetFrameLowering.h"
49#include "llvm/Target/TargetInstrInfo.h"
50#include "llvm/Target/TargetLowering.h"
51#include "llvm/Target/TargetLoweringObjectFile.h"
52#include "llvm/Target/TargetRegisterInfo.h"
53#include "llvm/Target/TargetSubtargetInfo.h"
54using namespace llvm;
55
56#define DEBUG_TYPE"asm-printer" "asm-printer"
57
58static const char *const DWARFGroupName = "DWARF Emission";
59static const char *const DbgTimerName = "Debug Info Emission";
60static const char *const EHTimerName = "DWARF Exception Writer";
61static const char *const CodeViewLineTablesGroupName = "CodeView Line Tables";
62
63STATISTIC(EmittedInsts, "Number of machine instrs printed")static llvm::Statistic EmittedInsts = { "asm-printer", "Number of machine instrs printed"
, 0, 0 };
64
65char AsmPrinter::ID = 0;
66
67typedef DenseMap<GCStrategy*, std::unique_ptr<GCMetadataPrinter>> gcp_map_type;
68static gcp_map_type &getGCMap(void *&P) {
69 if (!P)
70 P = new gcp_map_type();
71 return *(gcp_map_type*)P;
72}
73
74
75/// getGVAlignmentLog2 - Return the alignment to use for the specified global
76/// value in log2 form. This rounds up to the preferred alignment if possible
77/// and legal.
78static unsigned getGVAlignmentLog2(const GlobalValue *GV, const DataLayout &TD,
79 unsigned InBits = 0) {
80 unsigned NumBits = 0;
81 if (const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV))
82 NumBits = TD.getPreferredAlignmentLog(GVar);
83
84 // If InBits is specified, round it to it.
85 if (InBits > NumBits)
86 NumBits = InBits;
87
88 // If the GV has a specified alignment, take it into account.
89 if (GV->getAlignment() == 0)
90 return NumBits;
91
92 unsigned GVAlign = Log2_32(GV->getAlignment());
93
94 // If the GVAlign is larger than NumBits, or if we are required to obey
95 // NumBits because the GV has an assigned section, obey it.
96 if (GVAlign > NumBits || GV->hasSection())
97 NumBits = GVAlign;
98 return NumBits;
99}
100
101AsmPrinter::AsmPrinter(TargetMachine &tm, MCStreamer &Streamer)
102 : MachineFunctionPass(ID), TM(tm), MAI(tm.getMCAsmInfo()),
103 MII(tm.getSubtargetImpl()->getInstrInfo()),
104 OutContext(Streamer.getContext()), OutStreamer(Streamer), LastMI(nullptr),
105 LastFn(0), Counter(~0U), SetCounter(0) {
106 DD = nullptr; MMI = nullptr; LI = nullptr; MF = nullptr;
107 CurrentFnSym = CurrentFnSymForSize = nullptr;
108 GCMetadataPrinters = nullptr;
109 VerboseAsm = Streamer.isVerboseAsm();
110}
111
112AsmPrinter::~AsmPrinter() {
113 assert(!DD && Handlers.empty() && "Debug/EH info didn't get finalized")((!DD && Handlers.empty() && "Debug/EH info didn't get finalized"
) ? static_cast<void> (0) : __assert_fail ("!DD && Handlers.empty() && \"Debug/EH info didn't get finalized\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 113, __PRETTY_FUNCTION__));
114
115 if (GCMetadataPrinters) {
116 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
117
118 delete &GCMap;
119 GCMetadataPrinters = nullptr;
120 }
121
122 delete &OutStreamer;
123}
124
125/// getFunctionNumber - Return a unique ID for the current function.
126///
127unsigned AsmPrinter::getFunctionNumber() const {
128 return MF->getFunctionNumber();
129}
130
131const TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
132 return TM.getSubtargetImpl()->getTargetLowering()->getObjFileLowering();
133}
134
135/// getDataLayout - Return information about data layout.
136const DataLayout &AsmPrinter::getDataLayout() const {
137 return *TM.getSubtargetImpl()->getDataLayout();
138}
139
140const MCSubtargetInfo &AsmPrinter::getSubtargetInfo() const {
141 return TM.getSubtarget<MCSubtargetInfo>();
142}
143
144void AsmPrinter::EmitToStreamer(MCStreamer &S, const MCInst &Inst) {
145 S.EmitInstruction(Inst, getSubtargetInfo());
146}
147
148StringRef AsmPrinter::getTargetTriple() const {
149 return TM.getTargetTriple();
150}
151
152/// getCurrentSection() - Return the current section we are emitting to.
153const MCSection *AsmPrinter::getCurrentSection() const {
154 return OutStreamer.getCurrentSection().first;
155}
156
157
158
159void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
160 AU.setPreservesAll();
161 MachineFunctionPass::getAnalysisUsage(AU);
162 AU.addRequired<MachineModuleInfo>();
163 AU.addRequired<GCModuleInfo>();
164 if (isVerbose())
165 AU.addRequired<MachineLoopInfo>();
166}
167
168bool AsmPrinter::doInitialization(Module &M) {
169 MMI = getAnalysisIfAvailable<MachineModuleInfo>();
170 MMI->AnalyzeModule(M);
171
172 // Initialize TargetLoweringObjectFile.
173 const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
174 .Initialize(OutContext, TM);
175
176 OutStreamer.InitSections(false);
177
178 Mang = new Mangler(TM.getSubtargetImpl()->getDataLayout());
179
180 // Emit the version-min deplyment target directive if needed.
181 //
182 // FIXME: If we end up with a collection of these sorts of Darwin-specific
183 // or ELF-specific things, it may make sense to have a platform helper class
184 // that will work with the target helper class. For now keep it here, as the
185 // alternative is duplicated code in each of the target asm printers that
186 // use the directive, where it would need the same conditionalization
187 // anyway.
188 Triple TT(getTargetTriple());
189 if (TT.isOSDarwin()) {
190 unsigned Major, Minor, Update;
191 TT.getOSVersion(Major, Minor, Update);
192 // If there is a version specified, Major will be non-zero.
193 if (Major)
194 OutStreamer.EmitVersionMin((TT.isMacOSX() ?
195 MCVM_OSXVersionMin : MCVM_IOSVersionMin),
196 Major, Minor, Update);
197 }
198
199 // Allow the target to emit any magic that it wants at the start of the file.
200 EmitStartOfAsmFile(M);
201
202 // Very minimal debug info. It is ignored if we emit actual debug info. If we
203 // don't, this at least helps the user find where a global came from.
204 if (MAI->hasSingleParameterDotFile()) {
205 // .file "foo.c"
206 OutStreamer.EmitFileDirective(M.getModuleIdentifier());
207 }
208
209 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
210 assert(MI && "AsmPrinter didn't require GCModuleInfo?")((MI && "AsmPrinter didn't require GCModuleInfo?") ? static_cast
<void> (0) : __assert_fail ("MI && \"AsmPrinter didn't require GCModuleInfo?\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 210, __PRETTY_FUNCTION__));
211 for (auto &I : *MI)
212 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
213 MP->beginAssembly(M, *MI, *this);
214
215 // Emit module-level inline asm if it exists.
216 if (!M.getModuleInlineAsm().empty()) {
217 OutStreamer.AddComment("Start of file scope inline assembly");
218 OutStreamer.AddBlankLine();
219 EmitInlineAsm(M.getModuleInlineAsm()+"\n");
220 OutStreamer.AddComment("End of file scope inline assembly");
221 OutStreamer.AddBlankLine();
222 }
223
224 if (MAI->doesSupportDebugInformation()) {
225 if (Triple(TM.getTargetTriple()).isKnownWindowsMSVCEnvironment())
226 Handlers.push_back(HandlerInfo(new WinCodeViewLineTables(this),
227 DbgTimerName,
228 CodeViewLineTablesGroupName));
229 DD = new DwarfDebug(this, &M);
230 Handlers.push_back(HandlerInfo(DD, DbgTimerName, DWARFGroupName));
231 }
232
233 EHStreamer *ES = nullptr;
234 switch (MAI->getExceptionHandlingType()) {
235 case ExceptionHandling::None:
236 break;
237 case ExceptionHandling::SjLj:
238 case ExceptionHandling::DwarfCFI:
239 ES = new DwarfCFIException(this);
240 break;
241 case ExceptionHandling::ARM:
242 ES = new ARMException(this);
243 break;
244 case ExceptionHandling::ItaniumWinEH:
245 switch (MAI->getWinEHEncodingType()) {
246 default: llvm_unreachable("unsupported unwinding information encoding")::llvm::llvm_unreachable_internal("unsupported unwinding information encoding"
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 246);
247 case WinEH::EncodingType::Itanium:
248 ES = new Win64Exception(this);
249 break;
250 }
251 break;
252 }
253 if (ES)
254 Handlers.push_back(HandlerInfo(ES, EHTimerName, DWARFGroupName));
255 return false;
256}
257
258static bool canBeHidden(const GlobalValue *GV, const MCAsmInfo &MAI) {
259 if (!MAI.hasWeakDefCanBeHiddenDirective())
260 return false;
261
262 return canBeOmittedFromSymbolTable(GV);
263}
264
265void AsmPrinter::EmitLinkage(const GlobalValue *GV, MCSymbol *GVSym) const {
266 GlobalValue::LinkageTypes Linkage = GV->getLinkage();
267 switch (Linkage) {
268 case GlobalValue::CommonLinkage:
269 case GlobalValue::LinkOnceAnyLinkage:
270 case GlobalValue::LinkOnceODRLinkage:
271 case GlobalValue::WeakAnyLinkage:
272 case GlobalValue::WeakODRLinkage:
273 if (MAI->hasWeakDefDirective()) {
274 // .globl _foo
275 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
276
277 if (!canBeHidden(GV, *MAI))
278 // .weak_definition _foo
279 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefinition);
280 else
281 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_WeakDefAutoPrivate);
282 } else if (MAI->hasLinkOnceDirective()) {
283 // .globl _foo
284 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
285 //NOTE: linkonce is handled by the section the symbol was assigned to.
286 } else {
287 // .weak _foo
288 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Weak);
289 }
290 return;
291 case GlobalValue::AppendingLinkage:
292 // FIXME: appending linkage variables should go into a section of
293 // their name or something. For now, just emit them as external.
294 case GlobalValue::ExternalLinkage:
295 // If external or appending, declare as a global symbol.
296 // .globl _foo
297 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
298 return;
299 case GlobalValue::PrivateLinkage:
300 case GlobalValue::InternalLinkage:
301 return;
302 case GlobalValue::AvailableExternallyLinkage:
303 llvm_unreachable("Should never emit this")::llvm::llvm_unreachable_internal("Should never emit this", "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 303);
304 case GlobalValue::ExternalWeakLinkage:
305 llvm_unreachable("Don't know how to emit these")::llvm::llvm_unreachable_internal("Don't know how to emit these"
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 305);
306 }
307 llvm_unreachable("Unknown linkage type!")::llvm::llvm_unreachable_internal("Unknown linkage type!", "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 307);
308}
309
310void AsmPrinter::getNameWithPrefix(SmallVectorImpl<char> &Name,
311 const GlobalValue *GV) const {
312 TM.getNameWithPrefix(Name, GV, *Mang);
313}
314
315MCSymbol *AsmPrinter::getSymbol(const GlobalValue *GV) const {
316 return TM.getSymbol(GV, *Mang);
317}
318
319/// EmitGlobalVariable - Emit the specified global variable to the .s file.
320void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
321 if (GV->hasInitializer()) {
322 // Check to see if this is a special global used by LLVM, if so, emit it.
323 if (EmitSpecialLLVMGlobal(GV))
324 return;
325
326 if (isVerbose()) {
327 GV->printAsOperand(OutStreamer.GetCommentOS(),
328 /*PrintType=*/false, GV->getParent());
329 OutStreamer.GetCommentOS() << '\n';
330 }
331 }
332
333 MCSymbol *GVSym = getSymbol(GV);
334 EmitVisibility(GVSym, GV->getVisibility(), !GV->isDeclaration());
335
336 if (!GV->hasInitializer()) // External globals require no extra code.
337 return;
338
339 if (MAI->hasDotTypeDotSizeDirective())
340 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
341
342 SectionKind GVKind = TargetLoweringObjectFile::getKindForGlobal(GV, TM);
343
344 const DataLayout *DL = TM.getSubtargetImpl()->getDataLayout();
345 uint64_t Size = DL->getTypeAllocSize(GV->getType()->getElementType());
346
347 // If the alignment is specified, we *must* obey it. Overaligning a global
348 // with a specified alignment is a prompt way to break globals emitted to
349 // sections and expected to be contiguous (e.g. ObjC metadata).
350 unsigned AlignLog = getGVAlignmentLog2(GV, *DL);
351
352 for (const HandlerInfo &HI : Handlers) {
353 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled);
354 HI.Handler->setSymbolSize(GVSym, Size);
355 }
356
357 // Handle common and BSS local symbols (.lcomm).
358 if (GVKind.isCommon() || GVKind.isBSSLocal()) {
359 if (Size == 0) Size = 1; // .comm Foo, 0 is undefined, avoid it.
360 unsigned Align = 1 << AlignLog;
361
362 // Handle common symbols.
363 if (GVKind.isCommon()) {
364 if (!getObjFileLowering().getCommDirectiveSupportsAlignment())
365 Align = 0;
366
367 // .comm _foo, 42, 4
368 OutStreamer.EmitCommonSymbol(GVSym, Size, Align);
369 return;
370 }
371
372 // Handle local BSS symbols.
373 if (MAI->hasMachoZeroFillDirective()) {
374 const MCSection *TheSection =
375 getObjFileLowering().SectionForGlobal(GV, GVKind, *Mang, TM);
376 // .zerofill __DATA, __bss, _foo, 400, 5
377 OutStreamer.EmitZerofill(TheSection, GVSym, Size, Align);
378 return;
379 }
380
381 // Use .lcomm only if it supports user-specified alignment.
382 // Otherwise, while it would still be correct to use .lcomm in some
383 // cases (e.g. when Align == 1), the external assembler might enfore
384 // some -unknown- default alignment behavior, which could cause
385 // spurious differences between external and integrated assembler.
386 // Prefer to simply fall back to .local / .comm in this case.
387 if (MAI->getLCOMMDirectiveAlignmentType() != LCOMM::NoAlignment) {
388 // .lcomm _foo, 42
389 OutStreamer.EmitLocalCommonSymbol(GVSym, Size, Align);
390 return;
391 }
392
393 if (!getObjFileLowering().getCommDirectiveSupportsAlignment())
394 Align = 0;
395
396 // .local _foo
397 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local);
398 // .comm _foo, 42, 4
399 OutStreamer.EmitCommonSymbol(GVSym, Size, Align);
400 return;
401 }
402
403 const MCSection *TheSection =
404 getObjFileLowering().SectionForGlobal(GV, GVKind, *Mang, TM);
405
406 // Handle the zerofill directive on darwin, which is a special form of BSS
407 // emission.
408 if (GVKind.isBSSExtern() && MAI->hasMachoZeroFillDirective()) {
409 if (Size == 0) Size = 1; // zerofill of 0 bytes is undefined.
410
411 // .globl _foo
412 OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Global);
413 // .zerofill __DATA, __common, _foo, 400, 5
414 OutStreamer.EmitZerofill(TheSection, GVSym, Size, 1 << AlignLog);
415 return;
416 }
417
418 // Handle thread local data for mach-o which requires us to output an
419 // additional structure of data and mangle the original symbol so that we
420 // can reference it later.
421 //
422 // TODO: This should become an "emit thread local global" method on TLOF.
423 // All of this macho specific stuff should be sunk down into TLOFMachO and
424 // stuff like "TLSExtraDataSection" should no longer be part of the parent
425 // TLOF class. This will also make it more obvious that stuff like
426 // MCStreamer::EmitTBSSSymbol is macho specific and only called from macho
427 // specific code.
428 if (GVKind.isThreadLocal() && MAI->hasMachoTBSSDirective()) {
429 // Emit the .tbss symbol
430 MCSymbol *MangSym =
431 OutContext.GetOrCreateSymbol(GVSym->getName() + Twine("$tlv$init"));
432
433 if (GVKind.isThreadBSS()) {
434 TheSection = getObjFileLowering().getTLSBSSSection();
435 OutStreamer.EmitTBSSSymbol(TheSection, MangSym, Size, 1 << AlignLog);
436 } else if (GVKind.isThreadData()) {
437 OutStreamer.SwitchSection(TheSection);
438
439 EmitAlignment(AlignLog, GV);
440 OutStreamer.EmitLabel(MangSym);
441
442 EmitGlobalConstant(GV->getInitializer());
443 }
444
445 OutStreamer.AddBlankLine();
446
447 // Emit the variable struct for the runtime.
448 const MCSection *TLVSect
449 = getObjFileLowering().getTLSExtraDataSection();
450
451 OutStreamer.SwitchSection(TLVSect);
452 // Emit the linkage here.
453 EmitLinkage(GV, GVSym);
454 OutStreamer.EmitLabel(GVSym);
455
456 // Three pointers in size:
457 // - __tlv_bootstrap - used to make sure support exists
458 // - spare pointer, used when mapped by the runtime
459 // - pointer to mangled symbol above with initializer
460 unsigned PtrSize = DL->getPointerTypeSize(GV->getType());
461 OutStreamer.EmitSymbolValue(GetExternalSymbolSymbol("_tlv_bootstrap"),
462 PtrSize);
463 OutStreamer.EmitIntValue(0, PtrSize);
464 OutStreamer.EmitSymbolValue(MangSym, PtrSize);
465
466 OutStreamer.AddBlankLine();
467 return;
468 }
469
470 OutStreamer.SwitchSection(TheSection);
471
472 EmitLinkage(GV, GVSym);
473 EmitAlignment(AlignLog, GV);
474
475 OutStreamer.EmitLabel(GVSym);
476
477 EmitGlobalConstant(GV->getInitializer());
478
479 if (MAI->hasDotTypeDotSizeDirective())
480 // .size foo, 42
481 OutStreamer.EmitELFSize(GVSym, MCConstantExpr::Create(Size, OutContext));
482
483 OutStreamer.AddBlankLine();
484}
485
486/// EmitFunctionHeader - This method emits the header for the current
487/// function.
488void AsmPrinter::EmitFunctionHeader() {
489 // Print out constants referenced by the function
490 EmitConstantPool();
491
492 // Print the 'header' of function.
493 const Function *F = MF->getFunction();
494
495 OutStreamer.SwitchSection(
496 getObjFileLowering().SectionForGlobal(F, *Mang, TM));
497 EmitVisibility(CurrentFnSym, F->getVisibility());
498
499 EmitLinkage(F, CurrentFnSym);
500 EmitAlignment(MF->getAlignment(), F);
1
Calling 'AsmPrinter::EmitAlignment'
→
501
502 if (MAI->hasDotTypeDotSizeDirective())
503 OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
504
505 if (isVerbose()) {
506 F->printAsOperand(OutStreamer.GetCommentOS(),
507 /*PrintType=*/false, F->getParent());
508 OutStreamer.GetCommentOS() << '\n';
509 }
510
511 // Emit the prefix data.
512 if (F->hasPrefixData())
513 EmitGlobalConstant(F->getPrefixData());
514
515 // Emit the CurrentFnSym. This is a virtual function to allow targets to
516 // do their wild and crazy things as required.
517 EmitFunctionEntryLabel();
518
519 // If the function had address-taken blocks that got deleted, then we have
520 // references to the dangling symbols. Emit them at the start of the function
521 // so that we don't get references to undefined symbols.
522 std::vector<MCSymbol*> DeadBlockSyms;
523 MMI->takeDeletedSymbolsForFunction(F, DeadBlockSyms);
524 for (unsigned i = 0, e = DeadBlockSyms.size(); i != e; ++i) {
525 OutStreamer.AddComment("Address taken block that was later removed");
526 OutStreamer.EmitLabel(DeadBlockSyms[i]);
527 }
528
529 // Emit pre-function debug and/or EH information.
530 for (const HandlerInfo &HI : Handlers) {
531 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled);
532 HI.Handler->beginFunction(MF);
533 }
534
535 // Emit the prologue data.
536 if (F->hasPrologueData())
537 EmitGlobalConstant(F->getPrologueData());
538}
539
540/// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
541/// function. This can be overridden by targets as required to do custom stuff.
542void AsmPrinter::EmitFunctionEntryLabel() {
543 // The function label could have already been emitted if two symbols end up
544 // conflicting due to asm renaming. Detect this and emit an error.
545 if (CurrentFnSym->isUndefined())
546 return OutStreamer.EmitLabel(CurrentFnSym);
547
548 report_fatal_error("'" + Twine(CurrentFnSym->getName()) +
549 "' label emitted multiple times to assembly file");
550}
551
552/// emitComments - Pretty-print comments for instructions.
553static void emitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
554 const MachineFunction *MF = MI.getParent()->getParent();
555 const TargetMachine &TM = MF->getTarget();
556
557 // Check for spills and reloads
558 int FI;
559
560 const MachineFrameInfo *FrameInfo = MF->getFrameInfo();
561
562 // We assume a single instruction only has a spill or reload, not
563 // both.
564 const MachineMemOperand *MMO;
565 if (TM.getSubtargetImpl()->getInstrInfo()->isLoadFromStackSlotPostFE(&MI,
566 FI)) {
567 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
568 MMO = *MI.memoperands_begin();
569 CommentOS << MMO->getSize() << "-byte Reload\n";
570 }
571 } else if (TM.getSubtargetImpl()->getInstrInfo()->hasLoadFromStackSlot(
572 &MI, MMO, FI)) {
573 if (FrameInfo->isSpillSlotObjectIndex(FI))
574 CommentOS << MMO->getSize() << "-byte Folded Reload\n";
575 } else if (TM.getSubtargetImpl()->getInstrInfo()->isStoreToStackSlotPostFE(
576 &MI, FI)) {
577 if (FrameInfo->isSpillSlotObjectIndex(FI)) {
578 MMO = *MI.memoperands_begin();
579 CommentOS << MMO->getSize() << "-byte Spill\n";
580 }
581 } else if (TM.getSubtargetImpl()->getInstrInfo()->hasStoreToStackSlot(
582 &MI, MMO, FI)) {
583 if (FrameInfo->isSpillSlotObjectIndex(FI))
584 CommentOS << MMO->getSize() << "-byte Folded Spill\n";
585 }
586
587 // Check for spill-induced copies
588 if (MI.getAsmPrinterFlag(MachineInstr::ReloadReuse))
589 CommentOS << " Reload Reuse\n";
590}
591
592/// emitImplicitDef - This method emits the specified machine instruction
593/// that is an implicit def.
594void AsmPrinter::emitImplicitDef(const MachineInstr *MI) const {
595 unsigned RegNo = MI->getOperand(0).getReg();
596 OutStreamer.AddComment(
597 Twine("implicit-def: ") +
598 TM.getSubtargetImpl()->getRegisterInfo()->getName(RegNo));
599 OutStreamer.AddBlankLine();
600}
601
602static void emitKill(const MachineInstr *MI, AsmPrinter &AP) {
603 std::string Str = "kill:";
604 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
605 const MachineOperand &Op = MI->getOperand(i);
606 assert(Op.isReg() && "KILL instruction must have only register operands")((Op.isReg() && "KILL instruction must have only register operands"
) ? static_cast<void> (0) : __assert_fail ("Op.isReg() && \"KILL instruction must have only register operands\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 606, __PRETTY_FUNCTION__));
607 Str += ' ';
608 Str += AP.TM.getSubtargetImpl()->getRegisterInfo()->getName(Op.getReg());
609 Str += (Op.isDef() ? "<def>" : "<kill>");
610 }
611 AP.OutStreamer.AddComment(Str);
612 AP.OutStreamer.AddBlankLine();
613}
614
615/// emitDebugValueComment - This method handles the target-independent form
616/// of DBG_VALUE, returning true if it was able to do so. A false return
617/// means the target will need to handle MI in EmitInstruction.
618static bool emitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) {
619 // This code handles only the 4-operand target-independent form.
620 if (MI->getNumOperands() != 4)
621 return false;
622
623 SmallString<128> Str;
624 raw_svector_ostream OS(Str);
625 OS << "DEBUG_VALUE: ";
626
627 DIVariable V = MI->getDebugVariable();
628 if (V.getContext().isSubprogram()) {
629 StringRef Name = DISubprogram(V.getContext()).getDisplayName();
630 if (!Name.empty())
631 OS << Name << ":";
632 }
633 OS << V.getName();
634
635 DIExpression Expr = MI->getDebugExpression();
636 if (Expr.isVariablePiece())
637 OS << " [piece offset=" << Expr.getPieceOffset()
638 << " size=" << Expr.getPieceSize() << "]";
639 OS << " <- ";
640
641 // The second operand is only an offset if it's an immediate.
642 bool Deref = MI->getOperand(0).isReg() && MI->getOperand(1).isImm();
643 int64_t Offset = Deref ? MI->getOperand(1).getImm() : 0;
644
645 // Register or immediate value. Register 0 means undef.
646 if (MI->getOperand(0).isFPImm()) {
647 APFloat APF = APFloat(MI->getOperand(0).getFPImm()->getValueAPF());
648 if (MI->getOperand(0).getFPImm()->getType()->isFloatTy()) {
649 OS << (double)APF.convertToFloat();
650 } else if (MI->getOperand(0).getFPImm()->getType()->isDoubleTy()) {
651 OS << APF.convertToDouble();
652 } else {
653 // There is no good way to print long double. Convert a copy to
654 // double. Ah well, it's only a comment.
655 bool ignored;
656 APF.convert(APFloat::IEEEdouble, APFloat::rmNearestTiesToEven,
657 &ignored);
658 OS << "(long double) " << APF.convertToDouble();
659 }
660 } else if (MI->getOperand(0).isImm()) {
661 OS << MI->getOperand(0).getImm();
662 } else if (MI->getOperand(0).isCImm()) {
663 MI->getOperand(0).getCImm()->getValue().print(OS, false /*isSigned*/);
664 } else {
665 unsigned Reg;
666 if (MI->getOperand(0).isReg()) {
667 Reg = MI->getOperand(0).getReg();
668 } else {
669 assert(MI->getOperand(0).isFI() && "Unknown operand type")((MI->getOperand(0).isFI() && "Unknown operand type"
) ? static_cast<void> (0) : __assert_fail ("MI->getOperand(0).isFI() && \"Unknown operand type\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 669, __PRETTY_FUNCTION__));
670 const TargetFrameLowering *TFI =
671 AP.TM.getSubtargetImpl()->getFrameLowering();
672 Offset += TFI->getFrameIndexReference(*AP.MF,
673 MI->getOperand(0).getIndex(), Reg);
674 Deref = true;
675 }
676 if (Reg == 0) {
677 // Suppress offset, it is not meaningful here.
678 OS << "undef";
679 // NOTE: Want this comment at start of line, don't emit with AddComment.
680 AP.OutStreamer.emitRawComment(OS.str());
681 return true;
682 }
683 if (Deref)
684 OS << '[';
685 OS << AP.TM.getSubtargetImpl()->getRegisterInfo()->getName(Reg);
686 }
687
688 if (Deref)
689 OS << '+' << Offset << ']';
690
691 // NOTE: Want this comment at start of line, don't emit with AddComment.
692 AP.OutStreamer.emitRawComment(OS.str());
693 return true;
694}
695
696AsmPrinter::CFIMoveType AsmPrinter::needsCFIMoves() {
697 if (MAI->getExceptionHandlingType() == ExceptionHandling::DwarfCFI &&
698 MF->getFunction()->needsUnwindTableEntry())
699 return CFI_M_EH;
700
701 if (MMI->hasDebugInfo())
702 return CFI_M_Debug;
703
704 return CFI_M_None;
705}
706
707bool AsmPrinter::needsSEHMoves() {
708 return MAI->getExceptionHandlingType() == ExceptionHandling::ItaniumWinEH &&
709 MF->getFunction()->needsUnwindTableEntry();
710}
711
712void AsmPrinter::emitCFIInstruction(const MachineInstr &MI) {
713 ExceptionHandling ExceptionHandlingType = MAI->getExceptionHandlingType();
714 if (ExceptionHandlingType != ExceptionHandling::DwarfCFI &&
715 ExceptionHandlingType != ExceptionHandling::ARM)
716 return;
717
718 if (needsCFIMoves() == CFI_M_None)
719 return;
720
721 const MachineModuleInfo &MMI = MF->getMMI();
722 const std::vector<MCCFIInstruction> &Instrs = MMI.getFrameInstructions();
723 unsigned CFIIndex = MI.getOperand(0).getCFIIndex();
724 const MCCFIInstruction &CFI = Instrs[CFIIndex];
725 emitCFIInstruction(CFI);
726}
727
728/// EmitFunctionBody - This method emits the body and trailer for a
729/// function.
730void AsmPrinter::EmitFunctionBody() {
731 // Emit target-specific gunk before the function body.
732 EmitFunctionBodyStart();
733
734 bool ShouldPrintDebugScopes = MMI->hasDebugInfo();
735
736 // Print out code for the function.
737 bool HasAnyRealCode = false;
738 for (auto &MBB : *MF) {
739 // Print a label for the basic block.
740 EmitBasicBlockStart(MBB);
741 for (auto &MI : MBB) {
742
743 // Print the assembly for the instruction.
744 if (!MI.isPosition() && !MI.isImplicitDef() && !MI.isKill() &&
745 !MI.isDebugValue()) {
746 HasAnyRealCode = true;
747 ++EmittedInsts;
748 }
749
750 if (ShouldPrintDebugScopes) {
751 for (const HandlerInfo &HI : Handlers) {
752 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName,
753 TimePassesIsEnabled);
754 HI.Handler->beginInstruction(&MI);
755 }
756 }
757
758 if (isVerbose())
759 emitComments(MI, OutStreamer.GetCommentOS());
760
761 switch (MI.getOpcode()) {
762 case TargetOpcode::CFI_INSTRUCTION:
763 emitCFIInstruction(MI);
764 break;
765
766 case TargetOpcode::EH_LABEL:
767 case TargetOpcode::GC_LABEL:
768 OutStreamer.EmitLabel(MI.getOperand(0).getMCSymbol());
769 break;
770 case TargetOpcode::INLINEASM:
771 EmitInlineAsm(&MI);
772 break;
773 case TargetOpcode::DBG_VALUE:
774 if (isVerbose()) {
775 if (!emitDebugValueComment(&MI, *this))
776 EmitInstruction(&MI);
777 }
778 break;
779 case TargetOpcode::IMPLICIT_DEF:
780 if (isVerbose()) emitImplicitDef(&MI);
781 break;
782 case TargetOpcode::KILL:
783 if (isVerbose()) emitKill(&MI, *this);
784 break;
785 default:
786 EmitInstruction(&MI);
787 break;
788 }
789
790 if (ShouldPrintDebugScopes) {
791 for (const HandlerInfo &HI : Handlers) {
792 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName,
793 TimePassesIsEnabled);
794 HI.Handler->endInstruction();
795 }
796 }
797 }
798
799 EmitBasicBlockEnd(MBB);
800 }
801
802 // If the function is empty and the object file uses .subsections_via_symbols,
803 // then we need to emit *something* to the function body to prevent the
804 // labels from collapsing together. Just emit a noop.
805 if ((MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode)) {
806 MCInst Noop;
807 TM.getSubtargetImpl()->getInstrInfo()->getNoopForMachoTarget(Noop);
808 OutStreamer.AddComment("avoids zero-length function");
809
810 // Targets can opt-out of emitting the noop here by leaving the opcode
811 // unspecified.
812 if (Noop.getOpcode())
813 OutStreamer.EmitInstruction(Noop, getSubtargetInfo());
814 }
815
816 const Function *F = MF->getFunction();
817 for (const auto &BB : *F) {
818 if (!BB.hasAddressTaken())
819 continue;
820 MCSymbol *Sym = GetBlockAddressSymbol(&BB);
821 if (Sym->isDefined())
822 continue;
823 OutStreamer.AddComment("Address of block that was removed by CodeGen");
824 OutStreamer.EmitLabel(Sym);
825 }
826
827 // Emit target-specific gunk after the function body.
828 EmitFunctionBodyEnd();
829
830 // If the target wants a .size directive for the size of the function, emit
831 // it.
832 if (MAI->hasDotTypeDotSizeDirective()) {
833 // Create a symbol for the end of function, so we can get the size as
834 // difference between the function label and the temp label.
835 MCSymbol *FnEndLabel = OutContext.CreateTempSymbol();
836 OutStreamer.EmitLabel(FnEndLabel);
837
838 const MCExpr *SizeExp =
839 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(FnEndLabel, OutContext),
840 MCSymbolRefExpr::Create(CurrentFnSymForSize,
841 OutContext),
842 OutContext);
843 OutStreamer.EmitELFSize(CurrentFnSym, SizeExp);
844 }
845
846 // Emit post-function debug and/or EH information.
847 for (const HandlerInfo &HI : Handlers) {
848 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled);
849 HI.Handler->endFunction(MF);
850 }
851 MMI->EndFunction();
852
853 // Print out jump tables referenced by the function.
854 EmitJumpTableInfo();
855
856 OutStreamer.AddBlankLine();
857}
858
859static const MCExpr *lowerConstant(const Constant *CV, AsmPrinter &AP);
860
861bool AsmPrinter::doFinalization(Module &M) {
862 // Emit global variables.
863 for (const auto &G : M.globals())
864 EmitGlobalVariable(&G);
865
866 // Emit visibility info for declarations
867 for (const Function &F : M) {
868 if (!F.isDeclaration())
869 continue;
870 GlobalValue::VisibilityTypes V = F.getVisibility();
871 if (V == GlobalValue::DefaultVisibility)
872 continue;
873
874 MCSymbol *Name = getSymbol(&F);
875 EmitVisibility(Name, V, false);
876 }
877
878 // Get information about jump-instruction tables to print.
879 JumpInstrTableInfo *JITI = getAnalysisIfAvailable<JumpInstrTableInfo>();
880
881 if (JITI && !JITI->getTables().empty()) {
882 unsigned Arch = Triple(getTargetTriple()).getArch();
883 bool IsThumb = (Arch == Triple::thumb || Arch == Triple::thumbeb);
884 MCInst TrapInst;
885 TM.getSubtargetImpl()->getInstrInfo()->getTrap(TrapInst);
886 unsigned LogAlignment = llvm::Log2_64(JITI->entryByteAlignment());
887
888 // Emit the right section for these functions.
889 OutStreamer.SwitchSection(OutContext.getObjectFileInfo()->getTextSection());
890 for (const auto &KV : JITI->getTables()) {
891 uint64_t Count = 0;
892 for (const auto &FunPair : KV.second) {
893 // Emit the function labels to make this be a function entry point.
894 MCSymbol *FunSym =
895 OutContext.GetOrCreateSymbol(FunPair.second->getName());
896 EmitAlignment(LogAlignment);
897 if (IsThumb)
898 OutStreamer.EmitThumbFunc(FunSym);
899 if (MAI->hasDotTypeDotSizeDirective())
900 OutStreamer.EmitSymbolAttribute(FunSym, MCSA_ELF_TypeFunction);
901 OutStreamer.EmitLabel(FunSym);
902
903 // Emit the jump instruction to transfer control to the original
904 // function.
905 MCInst JumpToFun;
906 MCSymbol *TargetSymbol =
907 OutContext.GetOrCreateSymbol(FunPair.first->getName());
908 const MCSymbolRefExpr *TargetSymRef =
909 MCSymbolRefExpr::Create(TargetSymbol, MCSymbolRefExpr::VK_PLT,
910 OutContext);
911 TM.getSubtargetImpl()->getInstrInfo()->getUnconditionalBranch(
912 JumpToFun, TargetSymRef);
913 OutStreamer.EmitInstruction(JumpToFun, getSubtargetInfo());
914 ++Count;
915 }
916
917 // Emit enough padding instructions to fill up to the next power of two.
918 uint64_t Remaining = NextPowerOf2(Count) - Count;
919 for (uint64_t C = 0; C < Remaining; ++C) {
920 EmitAlignment(LogAlignment);
921 OutStreamer.EmitInstruction(TrapInst, getSubtargetInfo());
922 }
923
924 }
925 }
926
927 // Emit module flags.
928 SmallVector<Module::ModuleFlagEntry, 8> ModuleFlags;
929 M.getModuleFlagsMetadata(ModuleFlags);
930 if (!ModuleFlags.empty())
931 getObjFileLowering().emitModuleFlags(OutStreamer, ModuleFlags, *Mang, TM);
932
933 // Make sure we wrote out everything we need.
934 OutStreamer.Flush();
935
936 // Finalize debug and EH information.
937 for (const HandlerInfo &HI : Handlers) {
938 NamedRegionTimer T(HI.TimerName, HI.TimerGroupName,
939 TimePassesIsEnabled);
940 HI.Handler->endModule();
941 delete HI.Handler;
942 }
943 Handlers.clear();
944 DD = nullptr;
945
946 // If the target wants to know about weak references, print them all.
947 if (MAI->getWeakRefDirective()) {
948 // FIXME: This is not lazy, it would be nice to only print weak references
949 // to stuff that is actually used. Note that doing so would require targets
950 // to notice uses in operands (due to constant exprs etc). This should
951 // happen with the MC stuff eventually.
952
953 // Print out module-level global variables here.
954 for (const auto &G : M.globals()) {
955 if (!G.hasExternalWeakLinkage())
956 continue;
957 OutStreamer.EmitSymbolAttribute(getSymbol(&G), MCSA_WeakReference);
958 }
959
960 for (const auto &F : M) {
961 if (!F.hasExternalWeakLinkage())
962 continue;
963 OutStreamer.EmitSymbolAttribute(getSymbol(&F), MCSA_WeakReference);
964 }
965 }
966
967 OutStreamer.AddBlankLine();
968 for (const auto &Alias : M.aliases()) {
969 MCSymbol *Name = getSymbol(&Alias);
970
971 if (Alias.hasExternalLinkage() || !MAI->getWeakRefDirective())
972 OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
973 else if (Alias.hasWeakLinkage() || Alias.hasLinkOnceLinkage())
974 OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
975 else
976 assert(Alias.hasLocalLinkage() && "Invalid alias linkage")((Alias.hasLocalLinkage() && "Invalid alias linkage")
? static_cast<void> (0) : __assert_fail ("Alias.hasLocalLinkage() && \"Invalid alias linkage\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 976, __PRETTY_FUNCTION__));
977
978 EmitVisibility(Name, Alias.getVisibility());
979
980 // Emit the directives as assignments aka .set:
981 OutStreamer.EmitAssignment(Name, lowerConstant(Alias.getAliasee(), *this));
982 }
983
984 GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
985 assert(MI && "AsmPrinter didn't require GCModuleInfo?")((MI && "AsmPrinter didn't require GCModuleInfo?") ? static_cast
<void> (0) : __assert_fail ("MI && \"AsmPrinter didn't require GCModuleInfo?\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 985, __PRETTY_FUNCTION__));
986 for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
987 if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(**--I))
988 MP->finishAssembly(M, *MI, *this);
989
990 // Emit llvm.ident metadata in an '.ident' directive.
991 EmitModuleIdents(M);
992
993 // If we don't have any trampolines, then we don't require stack memory
994 // to be executable. Some targets have a directive to declare this.
995 Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
996 if (!InitTrampolineIntrinsic || InitTrampolineIntrinsic->use_empty())
997 if (const MCSection *S = MAI->getNonexecutableStackSection(OutContext))
998 OutStreamer.SwitchSection(S);
999
1000 // Allow the target to emit any magic that it wants at the end of the file,
1001 // after everything else has gone out.
1002 EmitEndOfAsmFile(M);
1003
1004 delete Mang; Mang = nullptr;
1005 MMI = nullptr;
1006
1007 OutStreamer.Finish();
1008 OutStreamer.reset();
1009
1010 return false;
1011}
1012
1013void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
1014 this->MF = &MF;
1015 // Get the function symbol.
1016 CurrentFnSym = getSymbol(MF.getFunction());
1017 CurrentFnSymForSize = CurrentFnSym;
1018
1019 if (isVerbose())
1020 LI = &getAnalysis<MachineLoopInfo>();
1021}
1022
1023namespace {
1024 // SectionCPs - Keep track the alignment, constpool entries per Section.
1025 struct SectionCPs {
1026 const MCSection *S;
1027 unsigned Alignment;
1028 SmallVector<unsigned, 4> CPEs;
1029 SectionCPs(const MCSection *s, unsigned a) : S(s), Alignment(a) {}
1030 };
1031}
1032
1033/// EmitConstantPool - Print to the current output stream assembly
1034/// representations of the constants in the constant pool MCP. This is
1035/// used to print out constants which have been "spilled to memory" by
1036/// the code generator.
1037///
1038void AsmPrinter::EmitConstantPool() {
1039 const MachineConstantPool *MCP = MF->getConstantPool();
1040 const std::vector<MachineConstantPoolEntry> &CP = MCP->getConstants();
1041 if (CP.empty()) return;
1042
1043 // Calculate sections for constant pool entries. We collect entries to go into
1044 // the same section together to reduce amount of section switch statements.
1045 SmallVector<SectionCPs, 4> CPSections;
1046 for (unsigned i = 0, e = CP.size(); i != e; ++i) {
1047 const MachineConstantPoolEntry &CPE = CP[i];
1048 unsigned Align = CPE.getAlignment();
1049
1050 SectionKind Kind =
1051 CPE.getSectionKind(TM.getSubtargetImpl()->getDataLayout());
1052
1053 const Constant *C = nullptr;
1054 if (!CPE.isMachineConstantPoolEntry())
1055 C = CPE.Val.ConstVal;
1056
1057 const MCSection *S = getObjFileLowering().getSectionForConstant(Kind, C);
1058
1059 // The number of sections are small, just do a linear search from the
1060 // last section to the first.
1061 bool Found = false;
1062 unsigned SecIdx = CPSections.size();
1063 while (SecIdx != 0) {
1064 if (CPSections[--SecIdx].S == S) {
1065 Found = true;
1066 break;
1067 }
1068 }
1069 if (!Found) {
1070 SecIdx = CPSections.size();
1071 CPSections.push_back(SectionCPs(S, Align));
1072 }
1073
1074 if (Align > CPSections[SecIdx].Alignment)
1075 CPSections[SecIdx].Alignment = Align;
1076 CPSections[SecIdx].CPEs.push_back(i);
1077 }
1078
1079 // Now print stuff into the calculated sections.
1080 const MCSection *CurSection = nullptr;
1081 unsigned Offset = 0;
1082 for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
1083 for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
1084 unsigned CPI = CPSections[i].CPEs[j];
1085 MCSymbol *Sym = GetCPISymbol(CPI);
1086 if (!Sym->isUndefined())
1087 continue;
1088
1089 if (CurSection != CPSections[i].S) {
1090 OutStreamer.SwitchSection(CPSections[i].S);
1091 EmitAlignment(Log2_32(CPSections[i].Alignment));
1092 CurSection = CPSections[i].S;
1093 Offset = 0;
1094 }
1095
1096 MachineConstantPoolEntry CPE = CP[CPI];
1097
1098 // Emit inter-object padding for alignment.
1099 unsigned AlignMask = CPE.getAlignment() - 1;
1100 unsigned NewOffset = (Offset + AlignMask) & ~AlignMask;
1101 OutStreamer.EmitZeros(NewOffset - Offset);
1102
1103 Type *Ty = CPE.getType();
1104 Offset = NewOffset +
1105 TM.getSubtargetImpl()->getDataLayout()->getTypeAllocSize(Ty);
1106
1107 OutStreamer.EmitLabel(Sym);
1108 if (CPE.isMachineConstantPoolEntry())
1109 EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
1110 else
1111 EmitGlobalConstant(CPE.Val.ConstVal);
1112 }
1113 }
1114}
1115
1116/// EmitJumpTableInfo - Print assembly representations of the jump tables used
1117/// by the current function to the current output stream.
1118///
1119void AsmPrinter::EmitJumpTableInfo() {
1120 const DataLayout *DL = MF->getSubtarget().getDataLayout();
1121 const MachineJumpTableInfo *MJTI = MF->getJumpTableInfo();
1122 if (!MJTI) return;
1123 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_Inline) return;
1124 const std::vector<MachineJumpTableEntry> &JT = MJTI->getJumpTables();
1125 if (JT.empty()) return;
1126
1127 // Pick the directive to use to print the jump table entries, and switch to
1128 // the appropriate section.
1129 const Function *F = MF->getFunction();
1130 bool JTInDiffSection = false;
1131 if (// In PIC mode, we need to emit the jump table to the same section as the
1132 // function body itself, otherwise the label differences won't make sense.
1133 // FIXME: Need a better predicate for this: what about custom entries?
1134 MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
1135 // We should also do if the section name is NULL or function is declared
1136 // in discardable section
1137 // FIXME: this isn't the right predicate, should be based on the MCSection
1138 // for the function.
1139 F->isWeakForLinker()) {
1140 OutStreamer.SwitchSection(
1141 getObjFileLowering().SectionForGlobal(F, *Mang, TM));
1142 } else {
1143 // Otherwise, drop it in the readonly section.
1144 const MCSection *ReadOnlySection =
1145 getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly(),
1146 /*C=*/nullptr);
1147 OutStreamer.SwitchSection(ReadOnlySection);
1148 JTInDiffSection = true;
1149 }
1150
1151 EmitAlignment(Log2_32(
1152 MJTI->getEntryAlignment(*TM.getSubtargetImpl()->getDataLayout())));
1153
1154 // Jump tables in code sections are marked with a data_region directive
1155 // where that's supported.
1156 if (!JTInDiffSection)
1157 OutStreamer.EmitDataRegion(MCDR_DataRegionJT32);
1158
1159 for (unsigned JTI = 0, e = JT.size(); JTI != e; ++JTI) {
1160 const std::vector<MachineBasicBlock*> &JTBBs = JT[JTI].MBBs;
1161
1162 // If this jump table was deleted, ignore it.
1163 if (JTBBs.empty()) continue;
1164
1165 // For the EK_LabelDifference32 entry, if using .set avoids a relocation,
1166 /// emit a .set directive for each unique entry.
1167 if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
1168 MAI->doesSetDirectiveSuppressesReloc()) {
1169 SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
1170 const TargetLowering *TLI = TM.getSubtargetImpl()->getTargetLowering();
1171 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
1172 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
1173 const MachineBasicBlock *MBB = JTBBs[ii];
1174 if (!EmittedSets.insert(MBB).second)
1175 continue;
1176
1177 // .set LJTSet, LBB32-base
1178 const MCExpr *LHS =
1179 MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1180 OutStreamer.EmitAssignment(GetJTSetSymbol(JTI, MBB->getNumber()),
1181 MCBinaryExpr::CreateSub(LHS, Base, OutContext));
1182 }
1183 }
1184
1185 // On some targets (e.g. Darwin) we want to emit two consecutive labels
1186 // before each jump table. The first label is never referenced, but tells
1187 // the assembler and linker the extents of the jump table object. The
1188 // second label is actually referenced by the code.
1189 if (JTInDiffSection && DL->hasLinkerPrivateGlobalPrefix())
1190 // FIXME: This doesn't have to have any specific name, just any randomly
1191 // named and numbered 'l' label would work. Simplify GetJTISymbol.
1192 OutStreamer.EmitLabel(GetJTISymbol(JTI, true));
1193
1194 OutStreamer.EmitLabel(GetJTISymbol(JTI));
1195
1196 for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii)
1197 EmitJumpTableEntry(MJTI, JTBBs[ii], JTI);
1198 }
1199 if (!JTInDiffSection)
1200 OutStreamer.EmitDataRegion(MCDR_DataRegionEnd);
1201}
1202
1203/// EmitJumpTableEntry - Emit a jump table entry for the specified MBB to the
1204/// current stream.
1205void AsmPrinter::EmitJumpTableEntry(const MachineJumpTableInfo *MJTI,
1206 const MachineBasicBlock *MBB,
1207 unsigned UID) const {
1208 assert(MBB && MBB->getNumber() >= 0 && "Invalid basic block")((MBB && MBB->getNumber() >= 0 && "Invalid basic block"
) ? static_cast<void> (0) : __assert_fail ("MBB && MBB->getNumber() >= 0 && \"Invalid basic block\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1208, __PRETTY_FUNCTION__));
1209 const MCExpr *Value = nullptr;
1210 switch (MJTI->getEntryKind()) {
1211 case MachineJumpTableInfo::EK_Inline:
1212 llvm_unreachable("Cannot emit EK_Inline jump table entry")::llvm::llvm_unreachable_internal("Cannot emit EK_Inline jump table entry"
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1212);
1213 case MachineJumpTableInfo::EK_Custom32:
1214 Value =
1215 TM.getSubtargetImpl()->getTargetLowering()->LowerCustomJumpTableEntry(
1216 MJTI, MBB, UID, OutContext);
1217 break;
1218 case MachineJumpTableInfo::EK_BlockAddress:
1219 // EK_BlockAddress - Each entry is a plain address of block, e.g.:
1220 // .word LBB123
1221 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1222 break;
1223 case MachineJumpTableInfo::EK_GPRel32BlockAddress: {
1224 // EK_GPRel32BlockAddress - Each entry is an address of block, encoded
1225 // with a relocation as gp-relative, e.g.:
1226 // .gprel32 LBB123
1227 MCSymbol *MBBSym = MBB->getSymbol();
1228 OutStreamer.EmitGPRel32Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
1229 return;
1230 }
1231
1232 case MachineJumpTableInfo::EK_GPRel64BlockAddress: {
1233 // EK_GPRel64BlockAddress - Each entry is an address of block, encoded
1234 // with a relocation as gp-relative, e.g.:
1235 // .gpdword LBB123
1236 MCSymbol *MBBSym = MBB->getSymbol();
1237 OutStreamer.EmitGPRel64Value(MCSymbolRefExpr::Create(MBBSym, OutContext));
1238 return;
1239 }
1240
1241 case MachineJumpTableInfo::EK_LabelDifference32: {
1242 // Each entry is the address of the block minus the address of the jump
1243 // table. This is used for PIC jump tables where gprel32 is not supported.
1244 // e.g.:
1245 // .word LBB123 - LJTI1_2
1246 // If the .set directive avoids relocations, this is emitted as:
1247 // .set L4_5_set_123, LBB123 - LJTI1_2
1248 // .word L4_5_set_123
1249 if (MAI->doesSetDirectiveSuppressesReloc()) {
1250 Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
1251 OutContext);
1252 break;
1253 }
1254 Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
1255 const TargetLowering *TLI = TM.getSubtargetImpl()->getTargetLowering();
1256 const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF, UID, OutContext);
1257 Value = MCBinaryExpr::CreateSub(Value, Base, OutContext);
1258 break;
1259 }
1260 }
1261
1262 assert(Value && "Unknown entry kind!")((Value && "Unknown entry kind!") ? static_cast<void
> (0) : __assert_fail ("Value && \"Unknown entry kind!\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1262, __PRETTY_FUNCTION__));
1263
1264 unsigned EntrySize =
1265 MJTI->getEntrySize(*TM.getSubtargetImpl()->getDataLayout());
1266 OutStreamer.EmitValue(Value, EntrySize);
1267}
1268
1269
1270/// EmitSpecialLLVMGlobal - Check to see if the specified global is a
1271/// special global used by LLVM. If so, emit it and return true, otherwise
1272/// do nothing and return false.
1273bool AsmPrinter::EmitSpecialLLVMGlobal(const GlobalVariable *GV) {
1274 if (GV->getName() == "llvm.used") {
1275 if (MAI->hasNoDeadStrip()) // No need to emit this at all.
1276 EmitLLVMUsedList(cast<ConstantArray>(GV->getInitializer()));
1277 return true;
1278 }
1279
1280 // Ignore debug and non-emitted data. This handles llvm.compiler.used.
1281 if (StringRef(GV->getSection()) == "llvm.metadata" ||
1282 GV->hasAvailableExternallyLinkage())
1283 return true;
1284
1285 if (!GV->hasAppendingLinkage()) return false;
1286
1287 assert(GV->hasInitializer() && "Not a special LLVM global!")((GV->hasInitializer() && "Not a special LLVM global!"
) ? static_cast<void> (0) : __assert_fail ("GV->hasInitializer() && \"Not a special LLVM global!\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1287, __PRETTY_FUNCTION__));
1288
1289 if (GV->getName() == "llvm.global_ctors") {
1290 EmitXXStructorList(GV->getInitializer(), /* isCtor */ true);
1291
1292 if (TM.getRelocationModel() == Reloc::Static &&
1293 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1294 StringRef Sym(".constructors_used");
1295 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1296 MCSA_Reference);
1297 }
1298 return true;
1299 }
1300
1301 if (GV->getName() == "llvm.global_dtors") {
1302 EmitXXStructorList(GV->getInitializer(), /* isCtor */ false);
1303
1304 if (TM.getRelocationModel() == Reloc::Static &&
1305 MAI->hasStaticCtorDtorReferenceInStaticMode()) {
1306 StringRef Sym(".destructors_used");
1307 OutStreamer.EmitSymbolAttribute(OutContext.GetOrCreateSymbol(Sym),
1308 MCSA_Reference);
1309 }
1310 return true;
1311 }
1312
1313 return false;
1314}
1315
1316/// EmitLLVMUsedList - For targets that define a MAI::UsedDirective, mark each
1317/// global in the specified llvm.used list for which emitUsedDirectiveFor
1318/// is true, as being used with this directive.
1319void AsmPrinter::EmitLLVMUsedList(const ConstantArray *InitList) {
1320 // Should be an array of 'i8*'.
1321 for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
1322 const GlobalValue *GV =
1323 dyn_cast<GlobalValue>(InitList->getOperand(i)->stripPointerCasts());
1324 if (GV)
1325 OutStreamer.EmitSymbolAttribute(getSymbol(GV), MCSA_NoDeadStrip);
1326 }
1327}
1328
1329namespace {
1330struct Structor {
1331 Structor() : Priority(0), Func(nullptr), ComdatKey(nullptr) {}
1332 int Priority;
1333 llvm::Constant *Func;
1334 llvm::GlobalValue *ComdatKey;
1335};
1336} // end namespace
1337
1338/// EmitXXStructorList - Emit the ctor or dtor list taking into account the init
1339/// priority.
1340void AsmPrinter::EmitXXStructorList(const Constant *List, bool isCtor) {
1341 // Should be an array of '{ int, void ()* }' structs. The first value is the
1342 // init priority.
1343 if (!isa<ConstantArray>(List)) return;
1344
1345 // Sanity check the structors list.
1346 const ConstantArray *InitList = dyn_cast<ConstantArray>(List);
1347 if (!InitList) return; // Not an array!
1348 StructType *ETy = dyn_cast<StructType>(InitList->getType()->getElementType());
1349 // FIXME: Only allow the 3-field form in LLVM 4.0.
1350 if (!ETy || ETy->getNumElements() < 2 || ETy->getNumElements() > 3)
1351 return; // Not an array of two or three elements!
1352 if (!isa<IntegerType>(ETy->getTypeAtIndex(0U)) ||
1353 !isa<PointerType>(ETy->getTypeAtIndex(1U))) return; // Not (int, ptr).
1354 if (ETy->getNumElements() == 3 && !isa<PointerType>(ETy->getTypeAtIndex(2U)))
1355 return; // Not (int, ptr, ptr).
1356
1357 // Gather the structors in a form that's convenient for sorting by priority.
1358 SmallVector<Structor, 8> Structors;
1359 for (Value *O : InitList->operands()) {
1360 ConstantStruct *CS = dyn_cast<ConstantStruct>(O);
1361 if (!CS) continue; // Malformed.
1362 if (CS->getOperand(1)->isNullValue())
1363 break; // Found a null terminator, skip the rest.
1364 ConstantInt *Priority = dyn_cast<ConstantInt>(CS->getOperand(0));
1365 if (!Priority) continue; // Malformed.
1366 Structors.push_back(Structor());
1367 Structor &S = Structors.back();
1368 S.Priority = Priority->getLimitedValue(65535);
1369 S.Func = CS->getOperand(1);
1370 if (ETy->getNumElements() == 3 && !CS->getOperand(2)->isNullValue())
1371 S.ComdatKey = dyn_cast<GlobalValue>(CS->getOperand(2)->stripPointerCasts());
1372 }
1373
1374 // Emit the function pointers in the target-specific order
1375 const DataLayout *DL = TM.getSubtargetImpl()->getDataLayout();
1376 unsigned Align = Log2_32(DL->getPointerPrefAlignment());
1377 std::stable_sort(Structors.begin(), Structors.end(),
1378 [](const Structor &L,
1379 const Structor &R) { return L.Priority < R.Priority; });
1380 for (Structor &S : Structors) {
1381 const TargetLoweringObjectFile &Obj = getObjFileLowering();
1382 const MCSymbol *KeySym = nullptr;
1383 if (GlobalValue *GV = S.ComdatKey) {
1384 if (GV->hasAvailableExternallyLinkage())
1385 // If the associated variable is available_externally, some other TU
1386 // will provide its dynamic initializer.
1387 continue;
1388
1389 KeySym = getSymbol(GV);
1390 }
1391 const MCSection *OutputSection =
1392 (isCtor ? Obj.getStaticCtorSection(S.Priority, KeySym)
1393 : Obj.getStaticDtorSection(S.Priority, KeySym));
1394 OutStreamer.SwitchSection(OutputSection);
1395 if (OutStreamer.getCurrentSection() != OutStreamer.getPreviousSection())
1396 EmitAlignment(Align);
1397 EmitXXStructor(S.Func);
1398 }
1399}
1400
1401void AsmPrinter::EmitModuleIdents(Module &M) {
1402 if (!MAI->hasIdentDirective())
1403 return;
1404
1405 if (const NamedMDNode *NMD = M.getNamedMetadata("llvm.ident")) {
1406 for (unsigned i = 0, e = NMD->getNumOperands(); i != e; ++i) {
1407 const MDNode *N = NMD->getOperand(i);
1408 assert(N->getNumOperands() == 1 &&((N->getNumOperands() == 1 && "llvm.ident metadata entry can have only one operand"
) ? static_cast<void> (0) : __assert_fail ("N->getNumOperands() == 1 && \"llvm.ident metadata entry can have only one operand\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1409, __PRETTY_FUNCTION__))
1409 "llvm.ident metadata entry can have only one operand")((N->getNumOperands() == 1 && "llvm.ident metadata entry can have only one operand"
) ? static_cast<void> (0) : __assert_fail ("N->getNumOperands() == 1 && \"llvm.ident metadata entry can have only one operand\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1409, __PRETTY_FUNCTION__));
1410 const MDString *S = cast<MDString>(N->getOperand(0));
1411 OutStreamer.EmitIdent(S->getString());
1412 }
1413 }
1414}
1415
1416//===--------------------------------------------------------------------===//
1417// Emission and print routines
1418//
1419
1420/// EmitInt8 - Emit a byte directive and value.
1421///
1422void AsmPrinter::EmitInt8(int Value) const {
1423 OutStreamer.EmitIntValue(Value, 1);
1424}
1425
1426/// EmitInt16 - Emit a short directive and value.
1427///
1428void AsmPrinter::EmitInt16(int Value) const {
1429 OutStreamer.EmitIntValue(Value, 2);
1430}
1431
1432/// EmitInt32 - Emit a long directive and value.
1433///
1434void AsmPrinter::EmitInt32(int Value) const {
1435 OutStreamer.EmitIntValue(Value, 4);
1436}
1437
1438/// Emit something like ".long Hi-Lo" where the size in bytes of the directive
1439/// is specified by Size and Hi/Lo specify the labels. This implicitly uses
1440/// .set if it avoids relocations.
1441void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
1442 unsigned Size) const {
1443 // Get the Hi-Lo expression.
1444 const MCExpr *Diff =
1445 MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(Hi, OutContext),
1446 MCSymbolRefExpr::Create(Lo, OutContext),
1447 OutContext);
1448
1449 if (!MAI->doesSetDirectiveSuppressesReloc()) {
1450 OutStreamer.EmitValue(Diff, Size);
1451 return;
1452 }
1453
1454 // Otherwise, emit with .set (aka assignment).
1455 MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
1456 OutStreamer.EmitAssignment(SetLabel, Diff);
1457 OutStreamer.EmitSymbolValue(SetLabel, Size);
1458}
1459
1460/// EmitLabelPlusOffset - Emit something like ".long Label+Offset"
1461/// where the size in bytes of the directive is specified by Size and Label
1462/// specifies the label. This implicitly uses .set if it is available.
1463void AsmPrinter::EmitLabelPlusOffset(const MCSymbol *Label, uint64_t Offset,
1464 unsigned Size,
1465 bool IsSectionRelative) const {
1466 if (MAI->needsDwarfSectionOffsetDirective() && IsSectionRelative) {
1467 OutStreamer.EmitCOFFSecRel32(Label);
1468 return;
1469 }
1470
1471 // Emit Label+Offset (or just Label if Offset is zero)
1472 const MCExpr *Expr = MCSymbolRefExpr::Create(Label, OutContext);
1473 if (Offset)
1474 Expr = MCBinaryExpr::CreateAdd(
1475 Expr, MCConstantExpr::Create(Offset, OutContext), OutContext);
1476
1477 OutStreamer.EmitValue(Expr, Size);
1478}
1479
1480//===----------------------------------------------------------------------===//
1481
1482// EmitAlignment - Emit an alignment directive to the specified power of
1483// two boundary. For example, if you pass in 3 here, you will get an 8
1484// byte alignment. If a global value is specified, and if that global has
1485// an explicit alignment requested, it will override the alignment request
1486// if required for correctness.
1487//
1488void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalObject *GV) const {
1489 if (GV)
2
←
Taking true branch
→
1490 NumBits = getGVAlignmentLog2(GV, *TM.getSubtargetImpl()->getDataLayout(),
1491 NumBits);
1492
1493 if (NumBits == 0) return; // 1-byte aligned: no need to emit alignment.
3
←
Taking false branch
→
1494
1495 if (getCurrentSection()->getKind().isText())
4
←
Taking false branch
→
1496 OutStreamer.EmitCodeAlignment(1 << NumBits);
1497 else
1498 OutStreamer.EmitValueToAlignment(1 << NumBits);
5
←
The result of the '<<' expression is undefined
1499}
1500
1501//===----------------------------------------------------------------------===//
1502// Constant emission.
1503//===----------------------------------------------------------------------===//
1504
1505/// lowerConstant - Lower the specified LLVM Constant to an MCExpr.
1506///
1507static const MCExpr *lowerConstant(const Constant *CV, AsmPrinter &AP) {
1508 MCContext &Ctx = AP.OutContext;
1509
1510 if (CV->isNullValue() || isa<UndefValue>(CV))
1511 return MCConstantExpr::Create(0, Ctx);
1512
1513 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV))
1514 return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
1515
1516 if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
1517 return MCSymbolRefExpr::Create(AP.getSymbol(GV), Ctx);
1518
1519 if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
1520 return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
1521
1522 const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
1523 if (!CE) {
1524 llvm_unreachable("Unknown constant value to lower!")::llvm::llvm_unreachable_internal("Unknown constant value to lower!"
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1524);
1525 }
1526
1527 if (const MCExpr *RelocExpr =
1528 AP.getObjFileLowering().getExecutableRelativeSymbol(CE, *AP.Mang,
1529 AP.TM))
1530 return RelocExpr;
1531
1532 switch (CE->getOpcode()) {
1533 default:
1534 // If the code isn't optimized, there may be outstanding folding
1535 // opportunities. Attempt to fold the expression using DataLayout as a
1536 // last resort before giving up.
1537 if (Constant *C = ConstantFoldConstantExpression(
1538 CE, AP.TM.getSubtargetImpl()->getDataLayout()))
1539 if (C != CE)
1540 return lowerConstant(C, AP);
1541
1542 // Otherwise report the problem to the user.
1543 {
1544 std::string S;
1545 raw_string_ostream OS(S);
1546 OS << "Unsupported expression in static initializer: ";
1547 CE->printAsOperand(OS, /*PrintType=*/false,
1548 !AP.MF ? nullptr : AP.MF->getFunction()->getParent());
1549 report_fatal_error(OS.str());
1550 }
1551 case Instruction::GetElementPtr: {
1552 const DataLayout &DL = *AP.TM.getSubtargetImpl()->getDataLayout();
1553 // Generate a symbolic expression for the byte address
1554 APInt OffsetAI(DL.getPointerTypeSizeInBits(CE->getType()), 0);
1555 cast<GEPOperator>(CE)->accumulateConstantOffset(DL, OffsetAI);
1556
1557 const MCExpr *Base = lowerConstant(CE->getOperand(0), AP);
1558 if (!OffsetAI)
1559 return Base;
1560
1561 int64_t Offset = OffsetAI.getSExtValue();
1562 return MCBinaryExpr::CreateAdd(Base, MCConstantExpr::Create(Offset, Ctx),
1563 Ctx);
1564 }
1565
1566 case Instruction::Trunc:
1567 // We emit the value and depend on the assembler to truncate the generated
1568 // expression properly. This is important for differences between
1569 // blockaddress labels. Since the two labels are in the same function, it
1570 // is reasonable to treat their delta as a 32-bit value.
1571 // FALL THROUGH.
1572 case Instruction::BitCast:
1573 return lowerConstant(CE->getOperand(0), AP);
1574
1575 case Instruction::IntToPtr: {
1576 const DataLayout &DL = *AP.TM.getSubtargetImpl()->getDataLayout();
1577 // Handle casts to pointers by changing them into casts to the appropriate
1578 // integer type. This promotes constant folding and simplifies this code.
1579 Constant *Op = CE->getOperand(0);
1580 Op = ConstantExpr::getIntegerCast(Op, DL.getIntPtrType(CV->getType()),
1581 false/*ZExt*/);
1582 return lowerConstant(Op, AP);
1583 }
1584
1585 case Instruction::PtrToInt: {
1586 const DataLayout &DL = *AP.TM.getSubtargetImpl()->getDataLayout();
1587 // Support only foldable casts to/from pointers that can be eliminated by
1588 // changing the pointer to the appropriately sized integer type.
1589 Constant *Op = CE->getOperand(0);
1590 Type *Ty = CE->getType();
1591
1592 const MCExpr *OpExpr = lowerConstant(Op, AP);
1593
1594 // We can emit the pointer value into this slot if the slot is an
1595 // integer slot equal to the size of the pointer.
1596 if (DL.getTypeAllocSize(Ty) == DL.getTypeAllocSize(Op->getType()))
1597 return OpExpr;
1598
1599 // Otherwise the pointer is smaller than the resultant integer, mask off
1600 // the high bits so we are sure to get a proper truncation if the input is
1601 // a constant expr.
1602 unsigned InBits = DL.getTypeAllocSizeInBits(Op->getType());
1603 const MCExpr *MaskExpr = MCConstantExpr::Create(~0ULL >> (64-InBits), Ctx);
1604 return MCBinaryExpr::CreateAnd(OpExpr, MaskExpr, Ctx);
1605 }
1606
1607 // The MC library also has a right-shift operator, but it isn't consistently
1608 // signed or unsigned between different targets.
1609 case Instruction::Add:
1610 case Instruction::Sub:
1611 case Instruction::Mul:
1612 case Instruction::SDiv:
1613 case Instruction::SRem:
1614 case Instruction::Shl:
1615 case Instruction::And:
1616 case Instruction::Or:
1617 case Instruction::Xor: {
1618 const MCExpr *LHS = lowerConstant(CE->getOperand(0), AP);
1619 const MCExpr *RHS = lowerConstant(CE->getOperand(1), AP);
1620 switch (CE->getOpcode()) {
1621 default: llvm_unreachable("Unknown binary operator constant cast expr")::llvm::llvm_unreachable_internal("Unknown binary operator constant cast expr"
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1621);
1622 case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
1623 case Instruction::Sub: return MCBinaryExpr::CreateSub(LHS, RHS, Ctx);
1624 case Instruction::Mul: return MCBinaryExpr::CreateMul(LHS, RHS, Ctx);
1625 case Instruction::SDiv: return MCBinaryExpr::CreateDiv(LHS, RHS, Ctx);
1626 case Instruction::SRem: return MCBinaryExpr::CreateMod(LHS, RHS, Ctx);
1627 case Instruction::Shl: return MCBinaryExpr::CreateShl(LHS, RHS, Ctx);
1628 case Instruction::And: return MCBinaryExpr::CreateAnd(LHS, RHS, Ctx);
1629 case Instruction::Or: return MCBinaryExpr::CreateOr (LHS, RHS, Ctx);
1630 case Instruction::Xor: return MCBinaryExpr::CreateXor(LHS, RHS, Ctx);
1631 }
1632 }
1633 }
1634}
1635
1636static void emitGlobalConstantImpl(const Constant *C, AsmPrinter &AP);
1637
1638/// isRepeatedByteSequence - Determine whether the given value is
1639/// composed of a repeated sequence of identical bytes and return the
1640/// byte value. If it is not a repeated sequence, return -1.
1641static int isRepeatedByteSequence(const ConstantDataSequential *V) {
1642 StringRef Data = V->getRawDataValues();
1643 assert(!Data.empty() && "Empty aggregates should be CAZ node")((!Data.empty() && "Empty aggregates should be CAZ node"
) ? static_cast<void> (0) : __assert_fail ("!Data.empty() && \"Empty aggregates should be CAZ node\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1643, __PRETTY_FUNCTION__));
1644 char C = Data[0];
1645 for (unsigned i = 1, e = Data.size(); i != e; ++i)
1646 if (Data[i] != C) return -1;
1647 return static_cast<uint8_t>(C); // Ensure 255 is not returned as -1.
1648}
1649
1650
1651/// isRepeatedByteSequence - Determine whether the given value is
1652/// composed of a repeated sequence of identical bytes and return the
1653/// byte value. If it is not a repeated sequence, return -1.
1654static int isRepeatedByteSequence(const Value *V, TargetMachine &TM) {
1655
1656 if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
1657 if (CI->getBitWidth() > 64) return -1;
1658
1659 uint64_t Size =
1660 TM.getSubtargetImpl()->getDataLayout()->getTypeAllocSize(V->getType());
1661 uint64_t Value = CI->getZExtValue();
1662
1663 // Make sure the constant is at least 8 bits long and has a power
1664 // of 2 bit width. This guarantees the constant bit width is
1665 // always a multiple of 8 bits, avoiding issues with padding out
1666 // to Size and other such corner cases.
1667 if (CI->getBitWidth() < 8 || !isPowerOf2_64(CI->getBitWidth())) return -1;
1668
1669 uint8_t Byte = static_cast<uint8_t>(Value);
1670
1671 for (unsigned i = 1; i < Size; ++i) {
1672 Value >>= 8;
1673 if (static_cast<uint8_t>(Value) != Byte) return -1;
1674 }
1675 return Byte;
1676 }
1677 if (const ConstantArray *CA = dyn_cast<ConstantArray>(V)) {
1678 // Make sure all array elements are sequences of the same repeated
1679 // byte.
1680 assert(CA->getNumOperands() != 0 && "Should be a CAZ")((CA->getNumOperands() != 0 && "Should be a CAZ") ?
static_cast<void> (0) : __assert_fail ("CA->getNumOperands() != 0 && \"Should be a CAZ\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1680, __PRETTY_FUNCTION__));
1681 int Byte = isRepeatedByteSequence(CA->getOperand(0), TM);
1682 if (Byte == -1) return -1;
1683
1684 for (unsigned i = 1, e = CA->getNumOperands(); i != e; ++i) {
1685 int ThisByte = isRepeatedByteSequence(CA->getOperand(i), TM);
1686 if (ThisByte == -1) return -1;
1687 if (Byte != ThisByte) return -1;
1688 }
1689 return Byte;
1690 }
1691
1692 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(V))
1693 return isRepeatedByteSequence(CDS);
1694
1695 return -1;
1696}
1697
1698static void emitGlobalConstantDataSequential(const ConstantDataSequential *CDS,
1699 AsmPrinter &AP){
1700
1701 // See if we can aggregate this into a .fill, if so, emit it as such.
1702 int Value = isRepeatedByteSequence(CDS, AP.TM);
1703 if (Value != -1) {
1704 uint64_t Bytes =
1705 AP.TM.getSubtargetImpl()->getDataLayout()->getTypeAllocSize(
1706 CDS->getType());
1707 // Don't emit a 1-byte object as a .fill.
1708 if (Bytes > 1)
1709 return AP.OutStreamer.EmitFill(Bytes, Value);
1710 }
1711
1712 // If this can be emitted with .ascii/.asciz, emit it as such.
1713 if (CDS->isString())
1714 return AP.OutStreamer.EmitBytes(CDS->getAsString());
1715
1716 // Otherwise, emit the values in successive locations.
1717 unsigned ElementByteSize = CDS->getElementByteSize();
1718 if (isa<IntegerType>(CDS->getElementType())) {
1719 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1720 if (AP.isVerbose())
1721 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64"l" "x" "\n",
1722 CDS->getElementAsInteger(i));
1723 AP.OutStreamer.EmitIntValue(CDS->getElementAsInteger(i),
1724 ElementByteSize);
1725 }
1726 } else if (ElementByteSize == 4) {
1727 // FP Constants are printed as integer constants to avoid losing
1728 // precision.
1729 assert(CDS->getElementType()->isFloatTy())((CDS->getElementType()->isFloatTy()) ? static_cast<
void> (0) : __assert_fail ("CDS->getElementType()->isFloatTy()"
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1729, __PRETTY_FUNCTION__));
1730 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1731 union {
1732 float F;
1733 uint32_t I;
1734 };
1735
1736 F = CDS->getElementAsFloat(i);
1737 if (AP.isVerbose())
1738 AP.OutStreamer.GetCommentOS() << "float " << F << '\n';
1739 AP.OutStreamer.EmitIntValue(I, 4);
1740 }
1741 } else {
1742 assert(CDS->getElementType()->isDoubleTy())((CDS->getElementType()->isDoubleTy()) ? static_cast<
void> (0) : __assert_fail ("CDS->getElementType()->isDoubleTy()"
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1742, __PRETTY_FUNCTION__));
1743 for (unsigned i = 0, e = CDS->getNumElements(); i != e; ++i) {
1744 union {
1745 double F;
1746 uint64_t I;
1747 };
1748
1749 F = CDS->getElementAsDouble(i);
1750 if (AP.isVerbose())
1751 AP.OutStreamer.GetCommentOS() << "double " << F << '\n';
1752 AP.OutStreamer.EmitIntValue(I, 8);
1753 }
1754 }
1755
1756 const DataLayout &DL = *AP.TM.getSubtargetImpl()->getDataLayout();
1757 unsigned Size = DL.getTypeAllocSize(CDS->getType());
1758 unsigned EmittedSize = DL.getTypeAllocSize(CDS->getType()->getElementType()) *
1759 CDS->getNumElements();
1760 if (unsigned Padding = Size - EmittedSize)
1761 AP.OutStreamer.EmitZeros(Padding);
1762
1763}
1764
1765static void emitGlobalConstantArray(const ConstantArray *CA, AsmPrinter &AP) {
1766 // See if we can aggregate some values. Make sure it can be
1767 // represented as a series of bytes of the constant value.
1768 int Value = isRepeatedByteSequence(CA, AP.TM);
1769
1770 if (Value != -1) {
1771 uint64_t Bytes =
1772 AP.TM.getSubtargetImpl()->getDataLayout()->getTypeAllocSize(
1773 CA->getType());
1774 AP.OutStreamer.EmitFill(Bytes, Value);
1775 }
1776 else {
1777 for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
1778 emitGlobalConstantImpl(CA->getOperand(i), AP);
1779 }
1780}
1781
1782static void emitGlobalConstantVector(const ConstantVector *CV, AsmPrinter &AP) {
1783 for (unsigned i = 0, e = CV->getType()->getNumElements(); i != e; ++i)
1784 emitGlobalConstantImpl(CV->getOperand(i), AP);
1785
1786 const DataLayout &DL = *AP.TM.getSubtargetImpl()->getDataLayout();
1787 unsigned Size = DL.getTypeAllocSize(CV->getType());
1788 unsigned EmittedSize = DL.getTypeAllocSize(CV->getType()->getElementType()) *
1789 CV->getType()->getNumElements();
1790 if (unsigned Padding = Size - EmittedSize)
1791 AP.OutStreamer.EmitZeros(Padding);
1792}
1793
1794static void emitGlobalConstantStruct(const ConstantStruct *CS, AsmPrinter &AP) {
1795 // Print the fields in successive locations. Pad to align if needed!
1796 const DataLayout *DL = AP.TM.getSubtargetImpl()->getDataLayout();
1797 unsigned Size = DL->getTypeAllocSize(CS->getType());
1798 const StructLayout *Layout = DL->getStructLayout(CS->getType());
1799 uint64_t SizeSoFar = 0;
1800 for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
1801 const Constant *Field = CS->getOperand(i);
1802
1803 // Check if padding is needed and insert one or more 0s.
1804 uint64_t FieldSize = DL->getTypeAllocSize(Field->getType());
1805 uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
1806 - Layout->getElementOffset(i)) - FieldSize;
1807 SizeSoFar += FieldSize + PadSize;
1808
1809 // Now print the actual field value.
1810 emitGlobalConstantImpl(Field, AP);
1811
1812 // Insert padding - this may include padding to increase the size of the
1813 // current field up to the ABI size (if the struct is not packed) as well
1814 // as padding to ensure that the next field starts at the right offset.
1815 AP.OutStreamer.EmitZeros(PadSize);
1816 }
1817 assert(SizeSoFar == Layout->getSizeInBytes() &&((SizeSoFar == Layout->getSizeInBytes() && "Layout of constant struct may be incorrect!"
) ? static_cast<void> (0) : __assert_fail ("SizeSoFar == Layout->getSizeInBytes() && \"Layout of constant struct may be incorrect!\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1818, __PRETTY_FUNCTION__))
1818 "Layout of constant struct may be incorrect!")((SizeSoFar == Layout->getSizeInBytes() && "Layout of constant struct may be incorrect!"
) ? static_cast<void> (0) : __assert_fail ("SizeSoFar == Layout->getSizeInBytes() && \"Layout of constant struct may be incorrect!\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1818, __PRETTY_FUNCTION__));
1819}
1820
1821static void emitGlobalConstantFP(const ConstantFP *CFP, AsmPrinter &AP) {
1822 APInt API = CFP->getValueAPF().bitcastToAPInt();
1823
1824 // First print a comment with what we think the original floating-point value
1825 // should have been.
1826 if (AP.isVerbose()) {
1827 SmallString<8> StrVal;
1828 CFP->getValueAPF().toString(StrVal);
1829
1830 if (CFP->getType())
1831 CFP->getType()->print(AP.OutStreamer.GetCommentOS());
1832 else
1833 AP.OutStreamer.GetCommentOS() << "Printing <null> Type";
1834 AP.OutStreamer.GetCommentOS() << ' ' << StrVal << '\n';
1835 }
1836
1837 // Now iterate through the APInt chunks, emitting them in endian-correct
1838 // order, possibly with a smaller chunk at beginning/end (e.g. for x87 80-bit
1839 // floats).
1840 unsigned NumBytes = API.getBitWidth() / 8;
1841 unsigned TrailingBytes = NumBytes % sizeof(uint64_t);
1842 const uint64_t *p = API.getRawData();
1843
1844 // PPC's long double has odd notions of endianness compared to how LLVM
1845 // handles it: p[0] goes first for *big* endian on PPC.
1846 if (AP.TM.getSubtargetImpl()->getDataLayout()->isBigEndian() &&
1847 !CFP->getType()->isPPC_FP128Ty()) {
1848 int Chunk = API.getNumWords() - 1;
1849
1850 if (TrailingBytes)
1851 AP.OutStreamer.EmitIntValue(p[Chunk--], TrailingBytes);
1852
1853 for (; Chunk >= 0; --Chunk)
1854 AP.OutStreamer.EmitIntValue(p[Chunk], sizeof(uint64_t));
1855 } else {
1856 unsigned Chunk;
1857 for (Chunk = 0; Chunk < NumBytes / sizeof(uint64_t); ++Chunk)
1858 AP.OutStreamer.EmitIntValue(p[Chunk], sizeof(uint64_t));
1859
1860 if (TrailingBytes)
1861 AP.OutStreamer.EmitIntValue(p[Chunk], TrailingBytes);
1862 }
1863
1864 // Emit the tail padding for the long double.
1865 const DataLayout &DL = *AP.TM.getSubtargetImpl()->getDataLayout();
1866 AP.OutStreamer.EmitZeros(DL.getTypeAllocSize(CFP->getType()) -
1867 DL.getTypeStoreSize(CFP->getType()));
1868}
1869
1870static void emitGlobalConstantLargeInt(const ConstantInt *CI, AsmPrinter &AP) {
1871 const DataLayout *DL = AP.TM.getSubtargetImpl()->getDataLayout();
1872 unsigned BitWidth = CI->getBitWidth();
1873
1874 // Copy the value as we may massage the layout for constants whose bit width
1875 // is not a multiple of 64-bits.
1876 APInt Realigned(CI->getValue());
1877 uint64_t ExtraBits = 0;
1878 unsigned ExtraBitsSize = BitWidth & 63;
1879
1880 if (ExtraBitsSize) {
1881 // The bit width of the data is not a multiple of 64-bits.
1882 // The extra bits are expected to be at the end of the chunk of the memory.
1883 // Little endian:
1884 // * Nothing to be done, just record the extra bits to emit.
1885 // Big endian:
1886 // * Record the extra bits to emit.
1887 // * Realign the raw data to emit the chunks of 64-bits.
1888 if (DL->isBigEndian()) {
1889 // Basically the structure of the raw data is a chunk of 64-bits cells:
1890 // 0 1 BitWidth / 64
1891 // [chunk1][chunk2] ... [chunkN].
1892 // The most significant chunk is chunkN and it should be emitted first.
1893 // However, due to the alignment issue chunkN contains useless bits.
1894 // Realign the chunks so that they contain only useless information:
1895 // ExtraBits 0 1 (BitWidth / 64) - 1
1896 // chu[nk1 chu][nk2 chu] ... [nkN-1 chunkN]
1897 ExtraBits = Realigned.getRawData()[0] &
1898 (((uint64_t)-1) >> (64 - ExtraBitsSize));
1899 Realigned = Realigned.lshr(ExtraBitsSize);
1900 } else
1901 ExtraBits = Realigned.getRawData()[BitWidth / 64];
1902 }
1903
1904 // We don't expect assemblers to support integer data directives
1905 // for more than 64 bits, so we emit the data in at most 64-bit
1906 // quantities at a time.
1907 const uint64_t *RawData = Realigned.getRawData();
1908 for (unsigned i = 0, e = BitWidth / 64; i != e; ++i) {
1909 uint64_t Val = DL->isBigEndian() ? RawData[e - i - 1] : RawData[i];
1910 AP.OutStreamer.EmitIntValue(Val, 8);
1911 }
1912
1913 if (ExtraBitsSize) {
1914 // Emit the extra bits after the 64-bits chunks.
1915
1916 // Emit a directive that fills the expected size.
1917 uint64_t Size = AP.TM.getSubtargetImpl()->getDataLayout()->getTypeAllocSize(
1918 CI->getType());
1919 Size -= (BitWidth / 64) * 8;
1920 assert(Size && Size * 8 >= ExtraBitsSize &&((Size && Size * 8 >= ExtraBitsSize && (ExtraBits
& (((uint64_t)-1) >> (64 - ExtraBitsSize))) == ExtraBits
&& "Directive too small for extra bits.") ? static_cast
<void> (0) : __assert_fail ("Size && Size * 8 >= ExtraBitsSize && (ExtraBits & (((uint64_t)-1) >> (64 - ExtraBitsSize))) == ExtraBits && \"Directive too small for extra bits.\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1922, __PRETTY_FUNCTION__))
1921 (ExtraBits & (((uint64_t)-1) >> (64 - ExtraBitsSize)))((Size && Size * 8 >= ExtraBitsSize && (ExtraBits
& (((uint64_t)-1) >> (64 - ExtraBitsSize))) == ExtraBits
&& "Directive too small for extra bits.") ? static_cast
<void> (0) : __assert_fail ("Size && Size * 8 >= ExtraBitsSize && (ExtraBits & (((uint64_t)-1) >> (64 - ExtraBitsSize))) == ExtraBits && \"Directive too small for extra bits.\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1922, __PRETTY_FUNCTION__))
1922 == ExtraBits && "Directive too small for extra bits.")((Size && Size * 8 >= ExtraBitsSize && (ExtraBits
& (((uint64_t)-1) >> (64 - ExtraBitsSize))) == ExtraBits
&& "Directive too small for extra bits.") ? static_cast
<void> (0) : __assert_fail ("Size && Size * 8 >= ExtraBitsSize && (ExtraBits & (((uint64_t)-1) >> (64 - ExtraBitsSize))) == ExtraBits && \"Directive too small for extra bits.\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 1922, __PRETTY_FUNCTION__));
1923 AP.OutStreamer.EmitIntValue(ExtraBits, Size);
1924 }
1925}
1926
1927static void emitGlobalConstantImpl(const Constant *CV, AsmPrinter &AP) {
1928 const DataLayout *DL = AP.TM.getSubtargetImpl()->getDataLayout();
1929 uint64_t Size = DL->getTypeAllocSize(CV->getType());
1930 if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV))
1931 return AP.OutStreamer.EmitZeros(Size);
1932
1933 if (const ConstantInt *CI = dyn_cast<ConstantInt>(CV)) {
1934 switch (Size) {
1935 case 1:
1936 case 2:
1937 case 4:
1938 case 8:
1939 if (AP.isVerbose())
1940 AP.OutStreamer.GetCommentOS() << format("0x%" PRIx64"l" "x" "\n",
1941 CI->getZExtValue());
1942 AP.OutStreamer.EmitIntValue(CI->getZExtValue(), Size);
1943 return;
1944 default:
1945 emitGlobalConstantLargeInt(CI, AP);
1946 return;
1947 }
1948 }
1949
1950 if (const ConstantFP *CFP = dyn_cast<ConstantFP>(CV))
1951 return emitGlobalConstantFP(CFP, AP);
1952
1953 if (isa<ConstantPointerNull>(CV)) {
1954 AP.OutStreamer.EmitIntValue(0, Size);
1955 return;
1956 }
1957
1958 if (const ConstantDataSequential *CDS = dyn_cast<ConstantDataSequential>(CV))
1959 return emitGlobalConstantDataSequential(CDS, AP);
1960
1961 if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
1962 return emitGlobalConstantArray(CVA, AP);
1963
1964 if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
1965 return emitGlobalConstantStruct(CVS, AP);
1966
1967 if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
1968 // Look through bitcasts, which might not be able to be MCExpr'ized (e.g. of
1969 // vectors).
1970 if (CE->getOpcode() == Instruction::BitCast)
1971 return emitGlobalConstantImpl(CE->getOperand(0), AP);
1972
1973 if (Size > 8) {
1974 // If the constant expression's size is greater than 64-bits, then we have
1975 // to emit the value in chunks. Try to constant fold the value and emit it
1976 // that way.
1977 Constant *New = ConstantFoldConstantExpression(CE, DL);
1978 if (New && New != CE)
1979 return emitGlobalConstantImpl(New, AP);
1980 }
1981 }
1982
1983 if (const ConstantVector *V = dyn_cast<ConstantVector>(CV))
1984 return emitGlobalConstantVector(V, AP);
1985
1986 // Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
1987 // thread the streamer with EmitValue.
1988 AP.OutStreamer.EmitValue(lowerConstant(CV, AP), Size);
1989}
1990
1991/// EmitGlobalConstant - Print a general LLVM constant to the .s file.
1992void AsmPrinter::EmitGlobalConstant(const Constant *CV) {
1993 uint64_t Size =
1994 TM.getSubtargetImpl()->getDataLayout()->getTypeAllocSize(CV->getType());
1995 if (Size)
1996 emitGlobalConstantImpl(CV, *this);
1997 else if (MAI->hasSubsectionsViaSymbols()) {
1998 // If the global has zero size, emit a single byte so that two labels don't
1999 // look like they are at the same location.
2000 OutStreamer.EmitIntValue(0, 1);
2001 }
2002}
2003
2004void AsmPrinter::EmitMachineConstantPoolValue(MachineConstantPoolValue *MCPV) {
2005 // Target doesn't support this yet!
2006 llvm_unreachable("Target does not support EmitMachineConstantPoolValue")::llvm::llvm_unreachable_internal("Target does not support EmitMachineConstantPoolValue"
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2006);
2007}
2008
2009void AsmPrinter::printOffset(int64_t Offset, raw_ostream &OS) const {
2010 if (Offset > 0)
2011 OS << '+' << Offset;
2012 else if (Offset < 0)
2013 OS << Offset;
2014}
2015
2016//===----------------------------------------------------------------------===//
2017// Symbol Lowering Routines.
2018//===----------------------------------------------------------------------===//
2019
2020/// GetTempSymbol - Return the MCSymbol corresponding to the assembler
2021/// temporary label with the specified stem and unique ID.
2022MCSymbol *AsmPrinter::GetTempSymbol(Twine Name, unsigned ID) const {
2023 const DataLayout *DL = TM.getSubtargetImpl()->getDataLayout();
2024 return OutContext.GetOrCreateSymbol(Twine(DL->getPrivateGlobalPrefix()) +
2025 Name + Twine(ID));
2026}
2027
2028/// GetTempSymbol - Return an assembler temporary label with the specified
2029/// stem.
2030MCSymbol *AsmPrinter::GetTempSymbol(Twine Name) const {
2031 const DataLayout *DL = TM.getSubtargetImpl()->getDataLayout();
2032 return OutContext.GetOrCreateSymbol(Twine(DL->getPrivateGlobalPrefix())+
2033 Name);
2034}
2035
2036
2037MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
2038 return MMI->getAddrLabelSymbol(BA->getBasicBlock());
2039}
2040
2041MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BasicBlock *BB) const {
2042 return MMI->getAddrLabelSymbol(BB);
2043}
2044
2045/// GetCPISymbol - Return the symbol for the specified constant pool entry.
2046MCSymbol *AsmPrinter::GetCPISymbol(unsigned CPID) const {
2047 const DataLayout *DL = TM.getSubtargetImpl()->getDataLayout();
2048 return OutContext.GetOrCreateSymbol
2049 (Twine(DL->getPrivateGlobalPrefix()) + "CPI" + Twine(getFunctionNumber())
2050 + "_" + Twine(CPID));
2051}
2052
2053/// GetJTISymbol - Return the symbol for the specified jump table entry.
2054MCSymbol *AsmPrinter::GetJTISymbol(unsigned JTID, bool isLinkerPrivate) const {
2055 return MF->getJTISymbol(JTID, OutContext, isLinkerPrivate);
2056}
2057
2058/// GetJTSetSymbol - Return the symbol for the specified jump table .set
2059/// FIXME: privatize to AsmPrinter.
2060MCSymbol *AsmPrinter::GetJTSetSymbol(unsigned UID, unsigned MBBID) const {
2061 const DataLayout *DL = TM.getSubtargetImpl()->getDataLayout();
2062 return OutContext.GetOrCreateSymbol
2063 (Twine(DL->getPrivateGlobalPrefix()) + Twine(getFunctionNumber()) + "_" +
2064 Twine(UID) + "_set_" + Twine(MBBID));
2065}
2066
2067MCSymbol *AsmPrinter::getSymbolWithGlobalValueBase(const GlobalValue *GV,
2068 StringRef Suffix) const {
2069 return getObjFileLowering().getSymbolWithGlobalValueBase(GV, Suffix, *Mang,
2070 TM);
2071}
2072
2073/// GetExternalSymbolSymbol - Return the MCSymbol for the specified
2074/// ExternalSymbol.
2075MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
2076 SmallString<60> NameStr;
2077 Mang->getNameWithPrefix(NameStr, Sym);
2078 return OutContext.GetOrCreateSymbol(NameStr.str());
2079}
2080
2081
2082
2083/// PrintParentLoopComment - Print comments about parent loops of this one.
2084static void PrintParentLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2085 unsigned FunctionNumber) {
2086 if (!Loop) return;
2087 PrintParentLoopComment(OS, Loop->getParentLoop(), FunctionNumber);
2088 OS.indent(Loop->getLoopDepth()*2)
2089 << "Parent Loop BB" << FunctionNumber << "_"
2090 << Loop->getHeader()->getNumber()
2091 << " Depth=" << Loop->getLoopDepth() << '\n';
2092}
2093
2094
2095/// PrintChildLoopComment - Print comments about child loops within
2096/// the loop for this basic block, with nesting.
2097static void PrintChildLoopComment(raw_ostream &OS, const MachineLoop *Loop,
2098 unsigned FunctionNumber) {
2099 // Add child loop information
2100 for (const MachineLoop *CL : *Loop) {
2101 OS.indent(CL->getLoopDepth()*2)
2102 << "Child Loop BB" << FunctionNumber << "_"
2103 << CL->getHeader()->getNumber() << " Depth " << CL->getLoopDepth()
2104 << '\n';
2105 PrintChildLoopComment(OS, CL, FunctionNumber);
2106 }
2107}
2108
2109/// emitBasicBlockLoopComments - Pretty-print comments for basic blocks.
2110static void emitBasicBlockLoopComments(const MachineBasicBlock &MBB,
2111 const MachineLoopInfo *LI,
2112 const AsmPrinter &AP) {
2113 // Add loop depth information
2114 const MachineLoop *Loop = LI->getLoopFor(&MBB);
2115 if (!Loop) return;
2116
2117 MachineBasicBlock *Header = Loop->getHeader();
2118 assert(Header && "No header for loop")((Header && "No header for loop") ? static_cast<void
> (0) : __assert_fail ("Header && \"No header for loop\""
, "/tmp/buildd/llvm-toolchain-snapshot-3.6~svn224240/lib/CodeGen/AsmPrinter/AsmPrinter.cpp"
, 2118, __PRETTY_FUNCTION__));
2119
2120 // If this block is not a loop header, just print out what is the loop header
2121 // and return.
2122 if (Header != &MBB) {
2123 AP.OutStreamer.AddComment(" in Loop: Header=BB" +
2124 Twine(AP.getFunctionNumber())+"_" +
2125 Twine(Loop->getHeader()->getNumber())+
2126 " Depth="+Twine(Loop->getLoopDepth()));
2127 return;
2128 }
2129
2130 // Otherwise, it is a loop header. Print out information about child and
2131 // parent loops.
2132 raw_ostream &OS = AP.OutStreamer.GetCommentOS();
2133
2134 PrintParentLoopComment(OS, Loop->getParentLoop(), AP.getFunctionNumber());
2135
2136 OS << "=>";
2137 OS.indent(Loop->getLoopDepth()*2-2);
2138
2139 OS << "This ";
2140 if (Loop->empty())
2141 OS << "Inner ";
2142 OS << "Loop Header: Depth=" + Twine(Loop->getLoopDepth()) << '\n';
2143
2144 PrintChildLoopComment(OS, Loop, AP.getFunctionNumber());
2145}
2146
2147
2148/// EmitBasicBlockStart - This method prints the label for the specified
2149/// MachineBasicBlock, an alignment (if present) and a comment describing
2150/// it if appropriate.
2151void AsmPrinter::EmitBasicBlockStart(const MachineBasicBlock &MBB) const {
2152 // Emit an alignment directive for this block, if needed.
2153 if (unsigned Align = MBB.getAlignment())
2154 EmitAlignment(Align);
2155
2156 // If the block has its address taken, emit any labels that were used to
2157 // reference the block. It is possible that there is more than one label
2158 // here, because multiple LLVM BB's may have been RAUW'd to this block after
2159 // the references were generated.
2160 if (MBB.hasAddressTaken()) {
2161 const BasicBlock *BB = MBB.getBasicBlock();
2162 if (isVerbose())
2163 OutStreamer.AddComment("Block address taken");
2164
2165 std::vector<MCSymbol*> Symbols = MMI->getAddrLabelSymbolToEmit(BB);
2166 for (auto *Sym : Symbols)
2167 OutStreamer.EmitLabel(Sym);
2168 }
2169
2170 // Print some verbose block comments.
2171 if (isVerbose()) {
2172 if (const BasicBlock *BB = MBB.getBasicBlock())
2173 if (BB->hasName())
2174 OutStreamer.AddComment("%" + BB->getName());
2175 emitBasicBlockLoopComments(MBB, LI, *this);
2176 }
2177
2178 // Print the main label for the block.
2179 if (MBB.pred_empty() || isBlockOnlyReachableByFallthrough(&MBB)) {
2180 if (isVerbose()) {
2181 // NOTE: Want this comment at start of line, don't emit with AddComment.
2182 OutStreamer.emitRawComment(" BB#" + Twine(MBB.getNumber()) + ":", false);
2183 }
2184 } else {
2185 OutStreamer.EmitLabel(MBB.getSymbol());
2186 }
2187}
2188
2189void AsmPrinter::EmitVisibility(MCSymbol *Sym, unsigned Visibility,
2190 bool IsDefinition) const {
2191 MCSymbolAttr Attr = MCSA_Invalid;
2192
2193 switch (Visibility) {
2194 default: break;
2195 case GlobalValue::HiddenVisibility:
2196 if (IsDefinition)
2197 Attr = MAI->getHiddenVisibilityAttr();
2198 else
2199 Attr = MAI->getHiddenDeclarationVisibilityAttr();
2200 break;
2201 case GlobalValue::ProtectedVisibility:
2202 Attr = MAI->getProtectedVisibilityAttr();
2203 break;
2204 }
2205
2206 if (Attr != MCSA_Invalid)
2207 OutStreamer.EmitSymbolAttribute(Sym, Attr);
2208}
2209
2210/// isBlockOnlyReachableByFallthough - Return true if the basic block has
2211/// exactly one predecessor and the control transfer mechanism between
2212/// the predecessor and this block is a fall-through.
2213bool AsmPrinter::
2214isBlockOnlyReachableByFallthrough(const MachineBasicBlock *MBB) const {
2215 // If this is a landing pad, it isn't a fall through. If it has no preds,
2216 // then nothing falls through to it.
2217 if (MBB->isLandingPad() || MBB->pred_empty())
2218 return false;
2219
2220 // If there isn't exactly one predecessor, it can't be a fall through.
2221 if (MBB->pred_size() > 1)
2222 return false;
2223
2224 // The predecessor has to be immediately before this block.
2225 MachineBasicBlock *Pred = *MBB->pred_begin();
2226 if (!Pred->isLayoutSuccessor(MBB))
2227 return false;
2228
2229 // If the block is completely empty, then it definitely does fall through.
2230 if (Pred->empty())
2231 return true;
2232
2233 // Check the terminators in the previous blocks
2234 for (const auto &MI : Pred->terminators()) {
2235 // If it is not a simple branch, we are in a table somewhere.
2236 if (!MI.isBranch() || MI.isIndirectBranch())
2237 return false;
2238
2239 // If we are the operands of one of the branches, this is not a fall
2240 // through. Note that targets with delay slots will usually bundle
2241 // terminators with the delay slot instruction.
2242 for (ConstMIBundleOperands OP(&MI); OP.isValid(); ++OP) {
2243 if (OP->isJTI())
2244 return false;
2245 if (OP->isMBB() && OP->getMBB() == MBB)
2246 return false;
2247 }
2248 }
2249
2250 return true;
2251}
2252
2253
2254
2255GCMetadataPrinter *AsmPrinter::GetOrCreateGCPrinter(GCStrategy &S) {
2256 if (!S.usesMetadata())
2257 return nullptr;
2258
2259 gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
2260 gcp_map_type::iterator GCPI = GCMap.find(&S);
2261 if (GCPI != GCMap.end())
2262 return GCPI->second.get();
2263
2264 const char *Name = S.getName().c_str();
2265
2266 for (GCMetadataPrinterRegistry::iterator
2267 I = GCMetadataPrinterRegistry::begin(),
2268 E = GCMetadataPrinterRegistry::end(); I != E; ++I)
2269 if (strcmp(Name, I->getName()) == 0) {
2270 std::unique_ptr<GCMetadataPrinter> GMP = I->instantiate();
2271 GMP->S = &S;
2272 auto IterBool = GCMap.insert(std::make_pair(&S, std::move(GMP)));
2273 return IterBool.first->second.get();
2274 }
2275
2276 report_fatal_error("no GCMetadataPrinter registered for GC: " + Twine(Name));
2277}
2278
2279/// Pin vtable to this file.
2280AsmPrinterHandler::~AsmPrinterHandler() {}