1 //===-- llvm/CodeGen/DwarfDebug.cpp - Dwarf Debug Framework ---------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains support for writing dwarf debug info into asm files.
12 //===----------------------------------------------------------------------===//
14 #define DEBUG_TYPE "dwarfdebug"
15 #include "DwarfDebug.h"
18 #include "DwarfAccelTable.h"
19 #include "DwarfUnit.h"
20 #include "llvm/ADT/STLExtras.h"
21 #include "llvm/ADT/Statistic.h"
22 #include "llvm/ADT/StringExtras.h"
23 #include "llvm/ADT/Triple.h"
24 #include "llvm/CodeGen/MachineFunction.h"
25 #include "llvm/CodeGen/MachineModuleInfo.h"
26 #include "llvm/DIBuilder.h"
27 #include "llvm/DebugInfo.h"
28 #include "llvm/IR/Constants.h"
29 #include "llvm/IR/DataLayout.h"
30 #include "llvm/IR/Instructions.h"
31 #include "llvm/IR/Module.h"
32 #include "llvm/IR/ValueHandle.h"
33 #include "llvm/MC/MCAsmInfo.h"
34 #include "llvm/MC/MCSection.h"
35 #include "llvm/MC/MCStreamer.h"
36 #include "llvm/MC/MCSymbol.h"
37 #include "llvm/Support/CommandLine.h"
38 #include "llvm/Support/Debug.h"
39 #include "llvm/Support/Dwarf.h"
40 #include "llvm/Support/ErrorHandling.h"
41 #include "llvm/Support/FormattedStream.h"
42 #include "llvm/Support/LEB128.h"
43 #include "llvm/Support/MD5.h"
44 #include "llvm/Support/Path.h"
45 #include "llvm/Support/Timer.h"
46 #include "llvm/Target/TargetFrameLowering.h"
47 #include "llvm/Target/TargetLoweringObjectFile.h"
48 #include "llvm/Target/TargetMachine.h"
49 #include "llvm/Target/TargetOptions.h"
50 #include "llvm/Target/TargetRegisterInfo.h"
54 DisableDebugInfoPrinting("disable-debug-info-print", cl::Hidden,
55 cl::desc("Disable debug info printing"));
57 static cl::opt<bool> UnknownLocations(
58 "use-unknown-locations", cl::Hidden,
59 cl::desc("Make an absence of debug location information explicit."),
62 static cl::opt<bool> GenerateCUHash("generate-cu-hash", cl::Hidden,
63 cl::desc("Add the CU hash as the dwo_id."),
67 GenerateGnuPubSections("generate-gnu-dwarf-pub-sections", cl::Hidden,
68 cl::desc("Generate GNU-style pubnames and pubtypes"),
71 static cl::opt<bool> GenerateARangeSection("generate-arange-section",
73 cl::desc("Generate dwarf aranges"),
77 enum DefaultOnOff { Default, Enable, Disable };
80 static cl::opt<DefaultOnOff>
81 DwarfAccelTables("dwarf-accel-tables", cl::Hidden,
82 cl::desc("Output prototype dwarf accelerator tables."),
83 cl::values(clEnumVal(Default, "Default for platform"),
84 clEnumVal(Enable, "Enabled"),
85 clEnumVal(Disable, "Disabled"), clEnumValEnd),
88 static cl::opt<DefaultOnOff>
89 SplitDwarf("split-dwarf", cl::Hidden,
90 cl::desc("Output DWARF5 split debug info."),
91 cl::values(clEnumVal(Default, "Default for platform"),
92 clEnumVal(Enable, "Enabled"),
93 clEnumVal(Disable, "Disabled"), clEnumValEnd),
96 static cl::opt<DefaultOnOff>
97 DwarfPubSections("generate-dwarf-pub-sections", cl::Hidden,
98 cl::desc("Generate DWARF pubnames and pubtypes sections"),
99 cl::values(clEnumVal(Default, "Default for platform"),
100 clEnumVal(Enable, "Enabled"),
101 clEnumVal(Disable, "Disabled"), clEnumValEnd),
104 static cl::opt<unsigned>
105 DwarfVersionNumber("dwarf-version", cl::Hidden,
106 cl::desc("Generate DWARF for dwarf version."), cl::init(0));
109 DwarfCURanges("generate-dwarf-cu-ranges", cl::Hidden,
110 cl::desc("Generate DW_AT_ranges for compile units"),
113 static const char *const DWARFGroupName = "DWARF Emission";
114 static const char *const DbgTimerName = "DWARF Debug Writer";
116 //===----------------------------------------------------------------------===//
120 /// resolve - Look in the DwarfDebug map for the MDNode that
121 /// corresponds to the reference.
122 template <typename T> T DbgVariable::resolve(DIRef<T> Ref) const {
123 return DD->resolve(Ref);
126 DIType DbgVariable::getType() const {
127 DIType Ty = Var.getType();
128 // FIXME: isBlockByrefVariable should be reformulated in terms of complex
129 // addresses instead.
130 if (Var.isBlockByrefVariable()) {
131 /* Byref variables, in Blocks, are declared by the programmer as
132 "SomeType VarName;", but the compiler creates a
133 __Block_byref_x_VarName struct, and gives the variable VarName
134 either the struct, or a pointer to the struct, as its type. This
135 is necessary for various behind-the-scenes things the compiler
136 needs to do with by-reference variables in blocks.
138 However, as far as the original *programmer* is concerned, the
139 variable should still have type 'SomeType', as originally declared.
141 The following function dives into the __Block_byref_x_VarName
142 struct to find the original type of the variable. This will be
143 passed back to the code generating the type for the Debug
144 Information Entry for the variable 'VarName'. 'VarName' will then
145 have the original type 'SomeType' in its debug information.
147 The original type 'SomeType' will be the type of the field named
148 'VarName' inside the __Block_byref_x_VarName struct.
150 NOTE: In order for this to not completely fail on the debugger
151 side, the Debug Information Entry for the variable VarName needs to
152 have a DW_AT_location that tells the debugger how to unwind through
153 the pointers and __Block_byref_x_VarName struct to find the actual
154 value of the variable. The function addBlockByrefType does this. */
156 uint16_t tag = Ty.getTag();
158 if (tag == dwarf::DW_TAG_pointer_type)
159 subType = resolve(DIDerivedType(Ty).getTypeDerivedFrom());
161 DIArray Elements = DICompositeType(subType).getTypeArray();
162 for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) {
163 DIDerivedType DT(Elements.getElement(i));
164 if (getName() == DT.getName())
165 return (resolve(DT.getTypeDerivedFrom()));
171 } // end llvm namespace
173 /// Return Dwarf Version by checking module flags.
174 static unsigned getDwarfVersionFromModule(const Module *M) {
175 Value *Val = M->getModuleFlag("Dwarf Version");
177 return dwarf::DWARF_VERSION;
178 return cast<ConstantInt>(Val)->getZExtValue();
181 DwarfDebug::DwarfDebug(AsmPrinter *A, Module *M)
182 : Asm(A), MMI(Asm->MMI), FirstCU(0), SourceIdMap(DIEValueAllocator),
183 PrevLabel(NULL), GlobalRangeCount(0),
184 InfoHolder(A, "info_string", DIEValueAllocator), HasCURanges(false),
185 UsedNonDefaultText(false),
186 SkeletonHolder(A, "skel_string", DIEValueAllocator) {
188 DwarfInfoSectionSym = DwarfAbbrevSectionSym = DwarfStrSectionSym = 0;
189 DwarfDebugRangeSectionSym = DwarfDebugLocSectionSym = DwarfLineSectionSym = 0;
190 DwarfAddrSectionSym = 0;
191 DwarfAbbrevDWOSectionSym = DwarfStrDWOSectionSym = 0;
192 FunctionBeginSym = FunctionEndSym = 0;
196 // Turn on accelerator tables for Darwin by default, pubnames by
197 // default for non-Darwin, and handle split dwarf.
198 bool IsDarwin = Triple(A->getTargetTriple()).isOSDarwin();
200 if (DwarfAccelTables == Default)
201 HasDwarfAccelTables = IsDarwin;
203 HasDwarfAccelTables = DwarfAccelTables == Enable;
205 if (SplitDwarf == Default)
206 HasSplitDwarf = false;
208 HasSplitDwarf = SplitDwarf == Enable;
210 if (DwarfPubSections == Default)
211 HasDwarfPubSections = !IsDarwin;
213 HasDwarfPubSections = DwarfPubSections == Enable;
215 DwarfVersion = DwarfVersionNumber
217 : getDwarfVersionFromModule(MMI->getModule());
220 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
225 // Switch to the specified MCSection and emit an assembler
226 // temporary label to it if SymbolStem is specified.
227 static MCSymbol *emitSectionSym(AsmPrinter *Asm, const MCSection *Section,
228 const char *SymbolStem = 0) {
229 Asm->OutStreamer.SwitchSection(Section);
233 MCSymbol *TmpSym = Asm->GetTempSymbol(SymbolStem);
234 Asm->OutStreamer.EmitLabel(TmpSym);
238 DwarfFile::~DwarfFile() {
239 for (SmallVectorImpl<DwarfUnit *>::iterator I = CUs.begin(), E = CUs.end();
244 MCSymbol *DwarfFile::getStringPoolSym() {
245 return Asm->GetTempSymbol(StringPref);
248 MCSymbol *DwarfFile::getStringPoolEntry(StringRef Str) {
249 std::pair<MCSymbol *, unsigned> &Entry =
250 StringPool.GetOrCreateValue(Str).getValue();
254 Entry.second = NextStringPoolNumber++;
255 return Entry.first = Asm->GetTempSymbol(StringPref, Entry.second);
258 unsigned DwarfFile::getStringPoolIndex(StringRef Str) {
259 std::pair<MCSymbol *, unsigned> &Entry =
260 StringPool.GetOrCreateValue(Str).getValue();
264 Entry.second = NextStringPoolNumber++;
265 Entry.first = Asm->GetTempSymbol(StringPref, Entry.second);
269 unsigned DwarfFile::getAddrPoolIndex(const MCSymbol *Sym, bool TLS) {
270 std::pair<AddrPool::iterator, bool> P = AddressPool.insert(
271 std::make_pair(Sym, AddressPoolEntry(NextAddrPoolNumber, TLS)));
273 ++NextAddrPoolNumber;
274 return P.first->second.Number;
277 // Define a unique number for the abbreviation.
279 void DwarfFile::assignAbbrevNumber(DIEAbbrev &Abbrev) {
280 // Check the set for priors.
281 DIEAbbrev *InSet = AbbreviationsSet.GetOrInsertNode(&Abbrev);
283 // If it's newly added.
284 if (InSet == &Abbrev) {
285 // Add to abbreviation list.
286 Abbreviations.push_back(&Abbrev);
288 // Assign the vector position + 1 as its number.
289 Abbrev.setNumber(Abbreviations.size());
291 // Assign existing abbreviation number.
292 Abbrev.setNumber(InSet->getNumber());
296 static bool isObjCClass(StringRef Name) {
297 return Name.startswith("+") || Name.startswith("-");
300 static bool hasObjCCategory(StringRef Name) {
301 if (!isObjCClass(Name))
304 return Name.find(") ") != StringRef::npos;
307 static void getObjCClassCategory(StringRef In, StringRef &Class,
308 StringRef &Category) {
309 if (!hasObjCCategory(In)) {
310 Class = In.slice(In.find('[') + 1, In.find(' '));
315 Class = In.slice(In.find('[') + 1, In.find('('));
316 Category = In.slice(In.find('[') + 1, In.find(' '));
320 static StringRef getObjCMethodName(StringRef In) {
321 return In.slice(In.find(' ') + 1, In.find(']'));
324 // Helper for sorting sections into a stable output order.
325 static bool SectionSort(const MCSection *A, const MCSection *B) {
326 std::string LA = (A ? A->getLabelBeginName() : "");
327 std::string LB = (B ? B->getLabelBeginName() : "");
331 // Add the various names to the Dwarf accelerator table names.
332 // TODO: Determine whether or not we should add names for programs
333 // that do not have a DW_AT_name or DW_AT_linkage_name field - this
334 // is only slightly different than the lookup of non-standard ObjC names.
335 static void addSubprogramNames(DwarfUnit *TheU, DISubprogram SP, DIE *Die) {
336 if (!SP.isDefinition())
338 TheU->addAccelName(SP.getName(), Die);
340 // If the linkage name is different than the name, go ahead and output
341 // that as well into the name table.
342 if (SP.getLinkageName() != "" && SP.getName() != SP.getLinkageName())
343 TheU->addAccelName(SP.getLinkageName(), Die);
345 // If this is an Objective-C selector name add it to the ObjC accelerator
347 if (isObjCClass(SP.getName())) {
348 StringRef Class, Category;
349 getObjCClassCategory(SP.getName(), Class, Category);
350 TheU->addAccelObjC(Class, Die);
352 TheU->addAccelObjC(Category, Die);
353 // Also add the base method name to the name table.
354 TheU->addAccelName(getObjCMethodName(SP.getName()), Die);
358 /// isSubprogramContext - Return true if Context is either a subprogram
359 /// or another context nested inside a subprogram.
360 bool DwarfDebug::isSubprogramContext(const MDNode *Context) {
363 DIDescriptor D(Context);
364 if (D.isSubprogram())
367 return isSubprogramContext(resolve(DIType(Context).getContext()));
371 // Find DIE for the given subprogram and attach appropriate DW_AT_low_pc
372 // and DW_AT_high_pc attributes. If there are global variables in this
373 // scope then create and insert DIEs for these variables.
374 DIE *DwarfDebug::updateSubprogramScopeDIE(DwarfCompileUnit *SPCU,
376 DIE *SPDie = SPCU->getDIE(SP);
378 assert(SPDie && "Unable to find subprogram DIE!");
380 // If we're updating an abstract DIE, then we will be adding the children and
381 // object pointer later on. But what we don't want to do is process the
382 // concrete DIE twice.
383 if (DIE *AbsSPDIE = AbstractSPDies.lookup(SP)) {
384 // Pick up abstract subprogram DIE.
386 SPCU->createAndAddDIE(dwarf::DW_TAG_subprogram, *SPCU->getUnitDie());
387 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_abstract_origin, AbsSPDIE);
389 DISubprogram SPDecl = SP.getFunctionDeclaration();
390 if (!SPDecl.isSubprogram()) {
391 // There is not any need to generate specification DIE for a function
392 // defined at compile unit level. If a function is defined inside another
393 // function then gdb prefers the definition at top level and but does not
394 // expect specification DIE in parent function. So avoid creating
395 // specification DIE for a function defined inside a function.
396 DIScope SPContext = resolve(SP.getContext());
397 if (SP.isDefinition() && !SPContext.isCompileUnit() &&
398 !SPContext.isFile() && !isSubprogramContext(SPContext)) {
399 SPCU->addFlag(SPDie, dwarf::DW_AT_declaration);
402 DICompositeType SPTy = SP.getType();
403 DIArray Args = SPTy.getTypeArray();
404 uint16_t SPTag = SPTy.getTag();
405 if (SPTag == dwarf::DW_TAG_subroutine_type)
406 SPCU->constructSubprogramArguments(*SPDie, Args);
407 DIE *SPDeclDie = SPDie;
408 SPDie = SPCU->createAndAddDIE(dwarf::DW_TAG_subprogram,
409 *SPCU->getUnitDie());
410 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_specification, SPDeclDie);
415 SPCU->addLabelAddress(SPDie, dwarf::DW_AT_low_pc, FunctionBeginSym);
416 SPCU->addLabelAddress(SPDie, dwarf::DW_AT_high_pc, FunctionEndSym);
418 const TargetRegisterInfo *RI = Asm->TM.getRegisterInfo();
419 MachineLocation Location(RI->getFrameRegister(*Asm->MF));
420 SPCU->addAddress(SPDie, dwarf::DW_AT_frame_base, Location);
422 // Add name to the name table, we do this here because we're guaranteed
423 // to have concrete versions of our DW_TAG_subprogram nodes.
424 addSubprogramNames(SPCU, SP, SPDie);
429 /// Check whether we should create a DIE for the given Scope, return true
430 /// if we don't create a DIE (the corresponding DIE is null).
431 bool DwarfDebug::isLexicalScopeDIENull(LexicalScope *Scope) {
432 if (Scope->isAbstractScope())
435 // We don't create a DIE if there is no Range.
436 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges();
440 if (Ranges.size() > 1)
443 // We don't create a DIE if we have a single Range and the end label
445 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin();
446 MCSymbol *End = getLabelAfterInsn(RI->second);
450 static void addSectionLabel(AsmPrinter *Asm, DwarfUnit *U, DIE *D,
451 dwarf::Attribute A, const MCSymbol *L,
452 const MCSymbol *Sec) {
453 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections())
454 U->addSectionLabel(D, A, L);
456 U->addSectionDelta(D, A, L, Sec);
459 void DwarfDebug::addScopeRangeList(DwarfCompileUnit *TheCU, DIE *ScopeDIE,
460 const SmallVectorImpl<InsnRange> &Range) {
461 // Emit offset in .debug_range as a relocatable label. emitDIE will handle
462 // emitting it appropriately.
463 MCSymbol *RangeSym = Asm->GetTempSymbol("debug_ranges", GlobalRangeCount++);
464 addSectionLabel(Asm, TheCU, ScopeDIE, dwarf::DW_AT_ranges, RangeSym,
465 DwarfDebugRangeSectionSym);
467 RangeSpanList List(RangeSym);
468 for (SmallVectorImpl<InsnRange>::const_iterator RI = Range.begin(),
471 RangeSpan Span(getLabelBeforeInsn(RI->first),
472 getLabelAfterInsn(RI->second));
473 List.addRange(std::move(Span));
476 // Add the range list to the set of ranges to be emitted.
477 TheCU->addRangeList(std::move(List));
480 // Construct new DW_TAG_lexical_block for this scope and attach
481 // DW_AT_low_pc/DW_AT_high_pc labels.
482 DIE *DwarfDebug::constructLexicalScopeDIE(DwarfCompileUnit *TheCU,
483 LexicalScope *Scope) {
484 if (isLexicalScopeDIENull(Scope))
487 DIE *ScopeDIE = new DIE(dwarf::DW_TAG_lexical_block);
488 if (Scope->isAbstractScope())
491 const SmallVectorImpl<InsnRange> &ScopeRanges = Scope->getRanges();
493 // If we have multiple ranges, emit them into the range section.
494 if (ScopeRanges.size() > 1) {
495 addScopeRangeList(TheCU, ScopeDIE, ScopeRanges);
499 // Construct the address range for this DIE.
500 SmallVectorImpl<InsnRange>::const_iterator RI = ScopeRanges.begin();
501 MCSymbol *Start = getLabelBeforeInsn(RI->first);
502 MCSymbol *End = getLabelAfterInsn(RI->second);
503 assert(End && "End label should not be null!");
505 assert(Start->isDefined() && "Invalid starting label for an inlined scope!");
506 assert(End->isDefined() && "Invalid end label for an inlined scope!");
508 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_low_pc, Start);
509 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_high_pc, End);
514 // This scope represents inlined body of a function. Construct DIE to
515 // represent this concrete inlined copy of the function.
516 DIE *DwarfDebug::constructInlinedScopeDIE(DwarfCompileUnit *TheCU,
517 LexicalScope *Scope) {
518 const SmallVectorImpl<InsnRange> &ScopeRanges = Scope->getRanges();
519 assert(!ScopeRanges.empty() &&
520 "LexicalScope does not have instruction markers!");
522 if (!Scope->getScopeNode())
524 DIScope DS(Scope->getScopeNode());
525 DISubprogram InlinedSP = getDISubprogram(DS);
526 DIE *OriginDIE = TheCU->getDIE(InlinedSP);
528 DEBUG(dbgs() << "Unable to find original DIE for an inlined subprogram.");
532 DIE *ScopeDIE = new DIE(dwarf::DW_TAG_inlined_subroutine);
533 TheCU->addDIEEntry(ScopeDIE, dwarf::DW_AT_abstract_origin, OriginDIE);
535 // If we have multiple ranges, emit them into the range section.
536 if (ScopeRanges.size() > 1)
537 addScopeRangeList(TheCU, ScopeDIE, ScopeRanges);
539 SmallVectorImpl<InsnRange>::const_iterator RI = ScopeRanges.begin();
540 MCSymbol *StartLabel = getLabelBeforeInsn(RI->first);
541 MCSymbol *EndLabel = getLabelAfterInsn(RI->second);
543 if (StartLabel == 0 || EndLabel == 0)
544 llvm_unreachable("Unexpected Start and End labels for an inlined scope!");
546 assert(StartLabel->isDefined() &&
547 "Invalid starting label for an inlined scope!");
548 assert(EndLabel->isDefined() && "Invalid end label for an inlined scope!");
550 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_low_pc, StartLabel);
551 TheCU->addLabelAddress(ScopeDIE, dwarf::DW_AT_high_pc, EndLabel);
554 InlinedSubprogramDIEs.insert(OriginDIE);
556 // Add the call site information to the DIE.
557 DILocation DL(Scope->getInlinedAt());
558 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_call_file, None,
559 getOrCreateSourceID(DL.getFilename(), DL.getDirectory(),
560 TheCU->getUniqueID()));
561 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_call_line, None, DL.getLineNumber());
563 // Add name to the name table, we do this here because we're guaranteed
564 // to have concrete versions of our DW_TAG_inlined_subprogram nodes.
565 addSubprogramNames(TheCU, InlinedSP, ScopeDIE);
570 DIE *DwarfDebug::createScopeChildrenDIE(DwarfCompileUnit *TheCU,
572 SmallVectorImpl<DIE *> &Children) {
573 DIE *ObjectPointer = NULL;
575 // Collect arguments for current function.
576 if (LScopes.isCurrentFunctionScope(Scope)) {
577 for (unsigned i = 0, N = CurrentFnArguments.size(); i < N; ++i)
578 if (DbgVariable *ArgDV = CurrentFnArguments[i])
580 TheCU->constructVariableDIE(*ArgDV, Scope->isAbstractScope())) {
581 Children.push_back(Arg);
582 if (ArgDV->isObjectPointer())
586 // If this is a variadic function, add an unspecified parameter.
587 DISubprogram SP(Scope->getScopeNode());
588 DIArray FnArgs = SP.getType().getTypeArray();
589 if (FnArgs.getElement(FnArgs.getNumElements() - 1)
590 .isUnspecifiedParameter()) {
591 DIE *Ellipsis = new DIE(dwarf::DW_TAG_unspecified_parameters);
592 Children.push_back(Ellipsis);
596 // Collect lexical scope children first.
597 const SmallVectorImpl<DbgVariable *> &Variables =
598 ScopeVariables.lookup(Scope);
599 for (unsigned i = 0, N = Variables.size(); i < N; ++i)
600 if (DIE *Variable = TheCU->constructVariableDIE(*Variables[i],
601 Scope->isAbstractScope())) {
602 Children.push_back(Variable);
603 if (Variables[i]->isObjectPointer())
604 ObjectPointer = Variable;
606 const SmallVectorImpl<LexicalScope *> &Scopes = Scope->getChildren();
607 for (unsigned j = 0, M = Scopes.size(); j < M; ++j)
608 if (DIE *Nested = constructScopeDIE(TheCU, Scopes[j]))
609 Children.push_back(Nested);
610 return ObjectPointer;
613 // Construct a DIE for this scope.
614 DIE *DwarfDebug::constructScopeDIE(DwarfCompileUnit *TheCU,
615 LexicalScope *Scope) {
616 if (!Scope || !Scope->getScopeNode())
619 DIScope DS(Scope->getScopeNode());
621 SmallVector<DIE *, 8> Children;
622 DIE *ObjectPointer = NULL;
623 bool ChildrenCreated = false;
625 // We try to create the scope DIE first, then the children DIEs. This will
626 // avoid creating un-used children then removing them later when we find out
627 // the scope DIE is null.
628 DIE *ScopeDIE = NULL;
629 if (Scope->getInlinedAt())
630 ScopeDIE = constructInlinedScopeDIE(TheCU, Scope);
631 else if (DS.isSubprogram()) {
632 ProcessedSPNodes.insert(DS);
633 if (Scope->isAbstractScope()) {
634 ScopeDIE = TheCU->getDIE(DS);
635 // Note down abstract DIE.
637 AbstractSPDies.insert(std::make_pair(DS, ScopeDIE));
639 ScopeDIE = updateSubprogramScopeDIE(TheCU, DISubprogram(DS));
641 // Early exit when we know the scope DIE is going to be null.
642 if (isLexicalScopeDIENull(Scope))
645 // We create children here when we know the scope DIE is not going to be
646 // null and the children will be added to the scope DIE.
647 ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children);
648 ChildrenCreated = true;
650 // There is no need to emit empty lexical block DIE.
651 std::pair<ImportedEntityMap::const_iterator,
652 ImportedEntityMap::const_iterator> Range =
654 ScopesWithImportedEntities.begin(),
655 ScopesWithImportedEntities.end(),
656 std::pair<const MDNode *, const MDNode *>(DS, (const MDNode *)0),
658 if (Children.empty() && Range.first == Range.second)
660 ScopeDIE = constructLexicalScopeDIE(TheCU, Scope);
661 assert(ScopeDIE && "Scope DIE should not be null.");
662 for (ImportedEntityMap::const_iterator i = Range.first; i != Range.second;
664 constructImportedEntityDIE(TheCU, i->second, ScopeDIE);
668 assert(Children.empty() &&
669 "We create children only when the scope DIE is not null.");
672 if (!ChildrenCreated)
673 // We create children when the scope DIE is not null.
674 ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children);
677 for (SmallVectorImpl<DIE *>::iterator I = Children.begin(),
680 ScopeDIE->addChild(*I);
682 if (DS.isSubprogram() && ObjectPointer != NULL)
683 TheCU->addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, ObjectPointer);
688 // Look up the source id with the given directory and source file names.
689 // If none currently exists, create a new id and insert it in the
690 // SourceIds map. This can update DirectoryNames and SourceFileNames maps
692 unsigned DwarfDebug::getOrCreateSourceID(StringRef FileName, StringRef DirName,
694 // If we print assembly, we can't separate .file entries according to
695 // compile units. Thus all files will belong to the default compile unit.
697 // FIXME: add a better feature test than hasRawTextSupport. Even better,
698 // extend .file to support this.
699 if (Asm->OutStreamer.hasRawTextSupport())
702 // If FE did not provide a file name, then assume stdin.
703 if (FileName.empty())
704 return getOrCreateSourceID("<stdin>", StringRef(), CUID);
706 // TODO: this might not belong here. See if we can factor this better.
707 if (DirName == CompilationDir)
710 // FileIDCUMap stores the current ID for the given compile unit.
711 unsigned SrcId = FileIDCUMap[CUID] + 1;
713 // We look up the CUID/file/dir by concatenating them with a zero byte.
714 SmallString<128> NamePair;
715 NamePair += utostr(CUID);
718 NamePair += '\0'; // Zero bytes are not allowed in paths.
719 NamePair += FileName;
721 StringMapEntry<unsigned> &Ent = SourceIdMap.GetOrCreateValue(NamePair, SrcId);
722 if (Ent.getValue() != SrcId)
723 return Ent.getValue();
725 FileIDCUMap[CUID] = SrcId;
726 // Print out a .file directive to specify files for .loc directives.
727 Asm->OutStreamer.EmitDwarfFileDirective(SrcId, DirName, FileName, CUID);
732 void DwarfDebug::addGnuPubAttributes(DwarfUnit *U, DIE *D) const {
733 if (!GenerateGnuPubSections)
736 addSectionLabel(Asm, U, D, dwarf::DW_AT_GNU_pubnames,
737 Asm->GetTempSymbol("gnu_pubnames", U->getUniqueID()),
738 DwarfGnuPubNamesSectionSym);
740 addSectionLabel(Asm, U, D, dwarf::DW_AT_GNU_pubtypes,
741 Asm->GetTempSymbol("gnu_pubtypes", U->getUniqueID()),
742 DwarfGnuPubTypesSectionSym);
745 // Create new DwarfCompileUnit for the given metadata node with tag
746 // DW_TAG_compile_unit.
747 DwarfCompileUnit *DwarfDebug::constructDwarfCompileUnit(DICompileUnit DIUnit) {
748 StringRef FN = DIUnit.getFilename();
749 CompilationDir = DIUnit.getDirectory();
751 DIE *Die = new DIE(dwarf::DW_TAG_compile_unit);
752 DwarfCompileUnit *NewCU = new DwarfCompileUnit(
753 InfoHolder.getUnits().size(), Die, DIUnit, Asm, this, &InfoHolder);
754 InfoHolder.addUnit(NewCU);
756 FileIDCUMap[NewCU->getUniqueID()] = 0;
758 NewCU->addString(Die, dwarf::DW_AT_producer, DIUnit.getProducer());
759 NewCU->addUInt(Die, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
760 DIUnit.getLanguage());
761 NewCU->addString(Die, dwarf::DW_AT_name, FN);
763 if (!useSplitDwarf()) {
764 NewCU->initStmtList(DwarfLineSectionSym);
766 // If we're using split dwarf the compilation dir is going to be in the
767 // skeleton CU and so we don't need to duplicate it here.
768 if (!CompilationDir.empty())
769 NewCU->addString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
771 addGnuPubAttributes(NewCU, Die);
774 if (DIUnit.isOptimized())
775 NewCU->addFlag(Die, dwarf::DW_AT_APPLE_optimized);
777 StringRef Flags = DIUnit.getFlags();
779 NewCU->addString(Die, dwarf::DW_AT_APPLE_flags, Flags);
781 if (unsigned RVer = DIUnit.getRunTimeVersion())
782 NewCU->addUInt(Die, dwarf::DW_AT_APPLE_major_runtime_vers,
783 dwarf::DW_FORM_data1, RVer);
788 if (useSplitDwarf()) {
789 NewCU->initSection(Asm->getObjFileLowering().getDwarfInfoDWOSection(),
790 DwarfInfoDWOSectionSym);
791 NewCU->setSkeleton(constructSkeletonCU(NewCU));
793 NewCU->initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
794 DwarfInfoSectionSym);
796 CUMap.insert(std::make_pair(DIUnit, NewCU));
797 CUDieMap.insert(std::make_pair(Die, NewCU));
801 // Construct subprogram DIE.
802 void DwarfDebug::constructSubprogramDIE(DwarfCompileUnit *TheCU,
804 // FIXME: We should only call this routine once, however, during LTO if a
805 // program is defined in multiple CUs we could end up calling it out of
806 // beginModule as we walk the CUs.
808 DwarfCompileUnit *&CURef = SPMap[N];
814 if (!SP.isDefinition())
815 // This is a method declaration which will be handled while constructing
819 DIE *SubprogramDie = TheCU->getOrCreateSubprogramDIE(SP);
821 // Expose as a global name.
822 TheCU->addGlobalName(SP.getName(), SubprogramDie, resolve(SP.getContext()));
825 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit *TheCU,
827 DIImportedEntity Module(N);
828 assert(Module.Verify());
829 if (DIE *D = TheCU->getOrCreateContextDIE(Module.getContext()))
830 constructImportedEntityDIE(TheCU, Module, D);
833 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit *TheCU,
834 const MDNode *N, DIE *Context) {
835 DIImportedEntity Module(N);
836 assert(Module.Verify());
837 return constructImportedEntityDIE(TheCU, Module, Context);
840 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit *TheCU,
841 const DIImportedEntity &Module,
843 assert(Module.Verify() &&
844 "Use one of the MDNode * overloads to handle invalid metadata");
845 assert(Context && "Should always have a context for an imported_module");
846 DIE *IMDie = new DIE(Module.getTag());
847 TheCU->insertDIE(Module, IMDie);
849 DIDescriptor Entity = Module.getEntity();
850 if (Entity.isNameSpace())
851 EntityDie = TheCU->getOrCreateNameSpace(DINameSpace(Entity));
852 else if (Entity.isSubprogram())
853 EntityDie = TheCU->getOrCreateSubprogramDIE(DISubprogram(Entity));
854 else if (Entity.isType())
855 EntityDie = TheCU->getOrCreateTypeDIE(DIType(Entity));
857 EntityDie = TheCU->getDIE(Entity);
858 unsigned FileID = getOrCreateSourceID(Module.getContext().getFilename(),
859 Module.getContext().getDirectory(),
860 TheCU->getUniqueID());
861 TheCU->addUInt(IMDie, dwarf::DW_AT_decl_file, None, FileID);
862 TheCU->addUInt(IMDie, dwarf::DW_AT_decl_line, None, Module.getLineNumber());
863 TheCU->addDIEEntry(IMDie, dwarf::DW_AT_import, EntityDie);
864 StringRef Name = Module.getName();
866 TheCU->addString(IMDie, dwarf::DW_AT_name, Name);
867 Context->addChild(IMDie);
870 // Emit all Dwarf sections that should come prior to the content. Create
871 // global DIEs and emit initial debug info sections. This is invoked by
872 // the target AsmPrinter.
873 void DwarfDebug::beginModule() {
874 if (DisableDebugInfoPrinting)
877 const Module *M = MMI->getModule();
879 // If module has named metadata anchors then use them, otherwise scan the
880 // module using debug info finder to collect debug info.
881 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
884 TypeIdentifierMap = generateDITypeIdentifierMap(CU_Nodes);
886 // Emit initial sections so we can reference labels later.
889 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
890 DICompileUnit CUNode(CU_Nodes->getOperand(i));
891 DwarfCompileUnit *CU = constructDwarfCompileUnit(CUNode);
892 DIArray ImportedEntities = CUNode.getImportedEntities();
893 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
894 ScopesWithImportedEntities.push_back(std::make_pair(
895 DIImportedEntity(ImportedEntities.getElement(i)).getContext(),
896 ImportedEntities.getElement(i)));
897 std::sort(ScopesWithImportedEntities.begin(),
898 ScopesWithImportedEntities.end(), less_first());
899 DIArray GVs = CUNode.getGlobalVariables();
900 for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i)
901 CU->createGlobalVariableDIE(DIGlobalVariable(GVs.getElement(i)));
902 DIArray SPs = CUNode.getSubprograms();
903 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i)
904 constructSubprogramDIE(CU, SPs.getElement(i));
905 DIArray EnumTypes = CUNode.getEnumTypes();
906 for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i)
907 CU->getOrCreateTypeDIE(EnumTypes.getElement(i));
908 DIArray RetainedTypes = CUNode.getRetainedTypes();
909 for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i)
910 CU->getOrCreateTypeDIE(RetainedTypes.getElement(i));
911 // Emit imported_modules last so that the relevant context is already
913 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
914 constructImportedEntityDIE(CU, ImportedEntities.getElement(i));
917 // Tell MMI that we have debug info.
918 MMI->setDebugInfoAvailability(true);
920 // Prime section data.
921 SectionMap[Asm->getObjFileLowering().getTextSection()];
924 // Attach DW_AT_inline attribute with inlined subprogram DIEs.
925 void DwarfDebug::computeInlinedDIEs() {
926 // Attach DW_AT_inline attribute with inlined subprogram DIEs.
927 for (SmallPtrSet<DIE *, 4>::iterator AI = InlinedSubprogramDIEs.begin(),
928 AE = InlinedSubprogramDIEs.end();
931 FirstCU->addUInt(ISP, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined);
933 for (DenseMap<const MDNode *, DIE *>::iterator AI = AbstractSPDies.begin(),
934 AE = AbstractSPDies.end();
936 DIE *ISP = AI->second;
937 if (InlinedSubprogramDIEs.count(ISP))
939 FirstCU->addUInt(ISP, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined);
943 // Collect info for variables that were optimized out.
944 void DwarfDebug::collectDeadVariables() {
945 const Module *M = MMI->getModule();
947 if (NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu")) {
948 for (unsigned i = 0, e = CU_Nodes->getNumOperands(); i != e; ++i) {
949 DICompileUnit TheCU(CU_Nodes->getOperand(i));
950 DIArray Subprograms = TheCU.getSubprograms();
951 for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) {
952 DISubprogram SP(Subprograms.getElement(i));
953 if (ProcessedSPNodes.count(SP) != 0)
955 if (!SP.isSubprogram())
957 if (!SP.isDefinition())
959 DIArray Variables = SP.getVariables();
960 if (Variables.getNumElements() == 0)
963 // Construct subprogram DIE and add variables DIEs.
964 DwarfCompileUnit *SPCU =
965 static_cast<DwarfCompileUnit *>(CUMap.lookup(TheCU));
966 assert(SPCU && "Unable to find Compile Unit!");
967 // FIXME: See the comment in constructSubprogramDIE about duplicate
969 constructSubprogramDIE(SPCU, SP);
970 DIE *SPDIE = SPCU->getDIE(SP);
971 for (unsigned vi = 0, ve = Variables.getNumElements(); vi != ve; ++vi) {
972 DIVariable DV(Variables.getElement(vi));
973 if (!DV.isVariable())
975 DbgVariable NewVar(DV, NULL, this);
976 if (DIE *VariableDIE = SPCU->constructVariableDIE(NewVar, false))
977 SPDIE->addChild(VariableDIE);
984 void DwarfDebug::finalizeModuleInfo() {
985 // Collect info for variables that were optimized out.
986 collectDeadVariables();
988 // Attach DW_AT_inline attribute with inlined subprogram DIEs.
989 computeInlinedDIEs();
991 // Handle anything that needs to be done on a per-unit basis after
992 // all other generation.
993 for (SmallVectorImpl<DwarfUnit *>::const_iterator I = getUnits().begin(),
994 E = getUnits().end();
996 DwarfUnit *TheU = *I;
997 // Emit DW_AT_containing_type attribute to connect types with their
998 // vtable holding type.
999 TheU->constructContainingTypeDIEs();
1001 // Add CU specific attributes if we need to add any.
1002 if (TheU->getUnitDie()->getTag() == dwarf::DW_TAG_compile_unit) {
1003 // If we're splitting the dwarf out now that we've got the entire
1004 // CU then add the dwo id to it.
1005 DwarfCompileUnit *SkCU =
1006 static_cast<DwarfCompileUnit *>(TheU->getSkeleton());
1007 if (useSplitDwarf()) {
1008 // This should be a unique identifier when we want to build .dwp files.
1010 if (GenerateCUHash) {
1011 DIEHash CUHash(Asm);
1012 ID = CUHash.computeCUSignature(*TheU->getUnitDie());
1014 TheU->addUInt(TheU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
1015 dwarf::DW_FORM_data8, ID);
1016 SkCU->addUInt(SkCU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
1017 dwarf::DW_FORM_data8, ID);
1020 // If we have code split among multiple sections or we've requested
1021 // it then emit a DW_AT_ranges attribute on the unit that will remain
1022 // in the .o file, otherwise add a DW_AT_low_pc.
1023 // FIXME: Also add a high pc if we can.
1024 // FIXME: We should use ranges if we have multiple compile units or
1025 // allow reordering of code ala .subsections_via_symbols in mach-o.
1026 DwarfCompileUnit *U = SkCU ? SkCU : static_cast<DwarfCompileUnit *>(TheU);
1027 if (useCURanges() && TheU->getRanges().size()) {
1028 addSectionLabel(Asm, U, U->getUnitDie(), dwarf::DW_AT_ranges,
1029 Asm->GetTempSymbol("cu_ranges", U->getUniqueID()),
1030 DwarfDebugRangeSectionSym);
1032 // A DW_AT_low_pc attribute may also be specified in combination with
1033 // DW_AT_ranges to specify the default base address for use in location
1034 // lists (see Section 2.6.2) and range lists (see Section 2.17.3).
1035 U->addUInt(U->getUnitDie(), dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr,
1038 U->addUInt(U->getUnitDie(), dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr,
1043 // Compute DIE offsets and sizes.
1044 InfoHolder.computeSizeAndOffsets();
1045 if (useSplitDwarf())
1046 SkeletonHolder.computeSizeAndOffsets();
1049 void DwarfDebug::endSections() {
1050 // Filter labels by section.
1051 for (size_t n = 0; n < ArangeLabels.size(); n++) {
1052 const SymbolCU &SCU = ArangeLabels[n];
1053 if (SCU.Sym->isInSection()) {
1054 // Make a note of this symbol and it's section.
1055 const MCSection *Section = &SCU.Sym->getSection();
1056 if (!Section->getKind().isMetadata())
1057 SectionMap[Section].push_back(SCU);
1059 // Some symbols (e.g. common/bss on mach-o) can have no section but still
1060 // appear in the output. This sucks as we rely on sections to build
1061 // arange spans. We can do it without, but it's icky.
1062 SectionMap[NULL].push_back(SCU);
1066 // Build a list of sections used.
1067 std::vector<const MCSection *> Sections;
1068 for (SectionMapType::iterator it = SectionMap.begin(); it != SectionMap.end();
1070 const MCSection *Section = it->first;
1071 Sections.push_back(Section);
1074 // Sort the sections into order.
1075 // This is only done to ensure consistent output order across different runs.
1076 std::sort(Sections.begin(), Sections.end(), SectionSort);
1078 // Add terminating symbols for each section.
1079 for (unsigned ID = 0; ID < Sections.size(); ID++) {
1080 const MCSection *Section = Sections[ID];
1081 MCSymbol *Sym = NULL;
1084 // We can't call MCSection::getLabelEndName, as it's only safe to do so
1085 // if we know the section name up-front. For user-created sections, the
1086 // resulting label may not be valid to use as a label. (section names can
1087 // use a greater set of characters on some systems)
1088 Sym = Asm->GetTempSymbol("debug_end", ID);
1089 Asm->OutStreamer.SwitchSection(Section);
1090 Asm->OutStreamer.EmitLabel(Sym);
1093 // Insert a final terminator.
1094 SectionMap[Section].push_back(SymbolCU(NULL, Sym));
1097 // For now only turn on CU ranges if we've explicitly asked for it,
1098 // we have -ffunction-sections enabled, we've emitted a function
1099 // into a unique section, or we're using LTO. If we're using LTO then
1100 // we can't know that any particular function in the module is correlated
1101 // to a particular CU and so we need to be conservative. At this point all
1102 // sections should be finalized except for dwarf sections.
1103 HasCURanges = DwarfCURanges || UsedNonDefaultText || (CUMap.size() > 1) ||
1104 TargetMachine::getFunctionSections();
1107 // Emit all Dwarf sections that should come after the content.
1108 void DwarfDebug::endModule() {
1115 // End any existing sections.
1116 // TODO: Does this need to happen?
1119 // Finalize the debug info for the module.
1120 finalizeModuleInfo();
1124 // Emit all the DIEs into a debug info section.
1127 // Corresponding abbreviations into a abbrev section.
1128 emitAbbreviations();
1130 // Emit info into a debug loc section.
1133 // Emit info into a debug aranges section.
1134 if (GenerateARangeSection)
1137 // Emit info into a debug ranges section.
1140 if (useSplitDwarf()) {
1143 emitDebugAbbrevDWO();
1144 // Emit DWO addresses.
1145 InfoHolder.emitAddresses(Asm->getObjFileLowering().getDwarfAddrSection());
1148 // Emit info into the dwarf accelerator table sections.
1149 if (useDwarfAccelTables()) {
1152 emitAccelNamespaces();
1156 // Emit the pubnames and pubtypes sections if requested.
1157 if (HasDwarfPubSections) {
1158 emitDebugPubNames(GenerateGnuPubSections);
1159 emitDebugPubTypes(GenerateGnuPubSections);
1165 // Reset these for the next Module if we have one.
1169 // Find abstract variable, if any, associated with Var.
1170 DbgVariable *DwarfDebug::findAbstractVariable(DIVariable &DV,
1171 DebugLoc ScopeLoc) {
1172 LLVMContext &Ctx = DV->getContext();
1173 // More then one inlined variable corresponds to one abstract variable.
1174 DIVariable Var = cleanseInlinedVariable(DV, Ctx);
1175 DbgVariable *AbsDbgVariable = AbstractVariables.lookup(Var);
1177 return AbsDbgVariable;
1179 LexicalScope *Scope = LScopes.findAbstractScope(ScopeLoc.getScope(Ctx));
1183 AbsDbgVariable = new DbgVariable(Var, NULL, this);
1184 addScopeVariable(Scope, AbsDbgVariable);
1185 AbstractVariables[Var] = AbsDbgVariable;
1186 return AbsDbgVariable;
1189 // If Var is a current function argument then add it to CurrentFnArguments list.
1190 bool DwarfDebug::addCurrentFnArgument(DbgVariable *Var, LexicalScope *Scope) {
1191 if (!LScopes.isCurrentFunctionScope(Scope))
1193 DIVariable DV = Var->getVariable();
1194 if (DV.getTag() != dwarf::DW_TAG_arg_variable)
1196 unsigned ArgNo = DV.getArgNumber();
1200 size_t Size = CurrentFnArguments.size();
1202 CurrentFnArguments.resize(CurFn->getFunction()->arg_size());
1203 // llvm::Function argument size is not good indicator of how many
1204 // arguments does the function have at source level.
1206 CurrentFnArguments.resize(ArgNo * 2);
1207 CurrentFnArguments[ArgNo - 1] = Var;
1211 // Collect variable information from side table maintained by MMI.
1212 void DwarfDebug::collectVariableInfoFromMMITable(
1213 SmallPtrSet<const MDNode *, 16> &Processed) {
1214 MachineModuleInfo::VariableDbgInfoMapTy &VMap = MMI->getVariableDbgInfo();
1215 for (MachineModuleInfo::VariableDbgInfoMapTy::iterator VI = VMap.begin(),
1218 const MDNode *Var = VI->first;
1221 Processed.insert(Var);
1223 const std::pair<unsigned, DebugLoc> &VP = VI->second;
1225 LexicalScope *Scope = LScopes.findLexicalScope(VP.second);
1227 // If variable scope is not found then skip this variable.
1231 DbgVariable *AbsDbgVariable = findAbstractVariable(DV, VP.second);
1232 DbgVariable *RegVar = new DbgVariable(DV, AbsDbgVariable, this);
1233 RegVar->setFrameIndex(VP.first);
1234 if (!addCurrentFnArgument(RegVar, Scope))
1235 addScopeVariable(Scope, RegVar);
1237 AbsDbgVariable->setFrameIndex(VP.first);
1241 // Return true if debug value, encoded by DBG_VALUE instruction, is in a
1243 static bool isDbgValueInDefinedReg(const MachineInstr *MI) {
1244 assert(MI->isDebugValue() && "Invalid DBG_VALUE machine instruction!");
1245 return MI->getNumOperands() == 3 && MI->getOperand(0).isReg() &&
1246 MI->getOperand(0).getReg() &&
1247 (MI->getOperand(1).isImm() ||
1248 (MI->getOperand(1).isReg() && MI->getOperand(1).getReg() == 0U));
1251 // Get .debug_loc entry for the instruction range starting at MI.
1252 static DotDebugLocEntry getDebugLocEntry(AsmPrinter *Asm,
1253 const MCSymbol *FLabel,
1254 const MCSymbol *SLabel,
1255 const MachineInstr *MI) {
1256 const MDNode *Var = MI->getOperand(MI->getNumOperands() - 1).getMetadata();
1258 assert(MI->getNumOperands() == 3);
1259 if (MI->getOperand(0).isReg()) {
1260 MachineLocation MLoc;
1261 // If the second operand is an immediate, this is a
1262 // register-indirect address.
1263 if (!MI->getOperand(1).isImm())
1264 MLoc.set(MI->getOperand(0).getReg());
1266 MLoc.set(MI->getOperand(0).getReg(), MI->getOperand(1).getImm());
1267 return DotDebugLocEntry(FLabel, SLabel, MLoc, Var);
1269 if (MI->getOperand(0).isImm())
1270 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getImm());
1271 if (MI->getOperand(0).isFPImm())
1272 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getFPImm());
1273 if (MI->getOperand(0).isCImm())
1274 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getCImm());
1276 llvm_unreachable("Unexpected 3 operand DBG_VALUE instruction!");
1279 // Find variables for each lexical scope.
1281 DwarfDebug::collectVariableInfo(SmallPtrSet<const MDNode *, 16> &Processed) {
1283 // Grab the variable info that was squirreled away in the MMI side-table.
1284 collectVariableInfoFromMMITable(Processed);
1286 for (SmallVectorImpl<const MDNode *>::const_iterator
1287 UVI = UserVariables.begin(),
1288 UVE = UserVariables.end();
1289 UVI != UVE; ++UVI) {
1290 const MDNode *Var = *UVI;
1291 if (Processed.count(Var))
1294 // History contains relevant DBG_VALUE instructions for Var and instructions
1296 SmallVectorImpl<const MachineInstr *> &History = DbgValues[Var];
1297 if (History.empty())
1299 const MachineInstr *MInsn = History.front();
1302 LexicalScope *Scope = NULL;
1303 if (DV.getTag() == dwarf::DW_TAG_arg_variable &&
1304 DISubprogram(DV.getContext()).describes(CurFn->getFunction()))
1305 Scope = LScopes.getCurrentFunctionScope();
1306 else if (MDNode *IA = DV.getInlinedAt())
1307 Scope = LScopes.findInlinedScope(DebugLoc::getFromDILocation(IA));
1309 Scope = LScopes.findLexicalScope(cast<MDNode>(DV->getOperand(1)));
1310 // If variable scope is not found then skip this variable.
1314 Processed.insert(DV);
1315 assert(MInsn->isDebugValue() && "History must begin with debug value");
1316 DbgVariable *AbsVar = findAbstractVariable(DV, MInsn->getDebugLoc());
1317 DbgVariable *RegVar = new DbgVariable(DV, AbsVar, this);
1318 if (!addCurrentFnArgument(RegVar, Scope))
1319 addScopeVariable(Scope, RegVar);
1321 AbsVar->setMInsn(MInsn);
1323 // Simplify ranges that are fully coalesced.
1324 if (History.size() <= 1 ||
1325 (History.size() == 2 && MInsn->isIdenticalTo(History.back()))) {
1326 RegVar->setMInsn(MInsn);
1330 // Handle multiple DBG_VALUE instructions describing one variable.
1331 RegVar->setDotDebugLocOffset(DotDebugLocEntries.size());
1333 for (SmallVectorImpl<const MachineInstr *>::const_iterator
1334 HI = History.begin(),
1337 const MachineInstr *Begin = *HI;
1338 assert(Begin->isDebugValue() && "Invalid History entry");
1340 // Check if DBG_VALUE is truncating a range.
1341 if (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() &&
1342 !Begin->getOperand(0).getReg())
1345 // Compute the range for a register location.
1346 const MCSymbol *FLabel = getLabelBeforeInsn(Begin);
1347 const MCSymbol *SLabel = 0;
1350 // If Begin is the last instruction in History then its value is valid
1351 // until the end of the function.
1352 SLabel = FunctionEndSym;
1354 const MachineInstr *End = HI[1];
1355 DEBUG(dbgs() << "DotDebugLoc Pair:\n"
1356 << "\t" << *Begin << "\t" << *End << "\n");
1357 if (End->isDebugValue())
1358 SLabel = getLabelBeforeInsn(End);
1360 // End is a normal instruction clobbering the range.
1361 SLabel = getLabelAfterInsn(End);
1362 assert(SLabel && "Forgot label after clobber instruction");
1367 // The value is valid until the next DBG_VALUE or clobber.
1368 DotDebugLocEntries.push_back(
1369 getDebugLocEntry(Asm, FLabel, SLabel, Begin));
1371 DotDebugLocEntries.push_back(DotDebugLocEntry());
1374 // Collect info for variables that were optimized out.
1375 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1376 DIArray Variables = DISubprogram(FnScope->getScopeNode()).getVariables();
1377 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1378 DIVariable DV(Variables.getElement(i));
1379 if (!DV || !DV.isVariable() || !Processed.insert(DV))
1381 if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext()))
1382 addScopeVariable(Scope, new DbgVariable(DV, NULL, this));
1386 // Return Label preceding the instruction.
1387 MCSymbol *DwarfDebug::getLabelBeforeInsn(const MachineInstr *MI) {
1388 MCSymbol *Label = LabelsBeforeInsn.lookup(MI);
1389 assert(Label && "Didn't insert label before instruction");
1393 // Return Label immediately following the instruction.
1394 MCSymbol *DwarfDebug::getLabelAfterInsn(const MachineInstr *MI) {
1395 return LabelsAfterInsn.lookup(MI);
1398 // Process beginning of an instruction.
1399 void DwarfDebug::beginInstruction(const MachineInstr *MI) {
1402 // Check if source location changes, but ignore DBG_VALUE locations.
1403 if (!MI->isDebugValue()) {
1404 DebugLoc DL = MI->getDebugLoc();
1405 if (DL != PrevInstLoc && (!DL.isUnknown() || UnknownLocations)) {
1408 if (DL == PrologEndLoc) {
1409 Flags |= DWARF2_FLAG_PROLOGUE_END;
1410 PrologEndLoc = DebugLoc();
1412 if (PrologEndLoc.isUnknown())
1413 Flags |= DWARF2_FLAG_IS_STMT;
1415 if (!DL.isUnknown()) {
1416 const MDNode *Scope = DL.getScope(Asm->MF->getFunction()->getContext());
1417 recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags);
1419 recordSourceLine(0, 0, 0, 0);
1423 // Insert labels where requested.
1424 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1425 LabelsBeforeInsn.find(MI);
1428 if (I == LabelsBeforeInsn.end())
1431 // Label already assigned.
1436 PrevLabel = MMI->getContext().CreateTempSymbol();
1437 Asm->OutStreamer.EmitLabel(PrevLabel);
1439 I->second = PrevLabel;
1442 // Process end of an instruction.
1443 void DwarfDebug::endInstruction() {
1445 // Don't create a new label after DBG_VALUE instructions.
1446 // They don't generate code.
1447 if (!CurMI->isDebugValue())
1450 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1451 LabelsAfterInsn.find(CurMI);
1455 if (I == LabelsAfterInsn.end())
1458 // Label already assigned.
1462 // We need a label after this instruction.
1464 PrevLabel = MMI->getContext().CreateTempSymbol();
1465 Asm->OutStreamer.EmitLabel(PrevLabel);
1467 I->second = PrevLabel;
1470 // Each LexicalScope has first instruction and last instruction to mark
1471 // beginning and end of a scope respectively. Create an inverse map that list
1472 // scopes starts (and ends) with an instruction. One instruction may start (or
1473 // end) multiple scopes. Ignore scopes that are not reachable.
1474 void DwarfDebug::identifyScopeMarkers() {
1475 SmallVector<LexicalScope *, 4> WorkList;
1476 WorkList.push_back(LScopes.getCurrentFunctionScope());
1477 while (!WorkList.empty()) {
1478 LexicalScope *S = WorkList.pop_back_val();
1480 const SmallVectorImpl<LexicalScope *> &Children = S->getChildren();
1481 if (!Children.empty())
1482 for (SmallVectorImpl<LexicalScope *>::const_iterator
1483 SI = Children.begin(),
1484 SE = Children.end();
1486 WorkList.push_back(*SI);
1488 if (S->isAbstractScope())
1491 const SmallVectorImpl<InsnRange> &Ranges = S->getRanges();
1494 for (SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin(),
1497 assert(RI->first && "InsnRange does not have first instruction!");
1498 assert(RI->second && "InsnRange does not have second instruction!");
1499 requestLabelBeforeInsn(RI->first);
1500 requestLabelAfterInsn(RI->second);
1505 // Gather pre-function debug information. Assumes being called immediately
1506 // after the function entry point has been emitted.
1507 void DwarfDebug::beginFunction(const MachineFunction *MF) {
1510 // If there's no debug info for the function we're not going to do anything.
1511 if (!MMI->hasDebugInfo())
1514 // Grab the lexical scopes for the function, if we don't have any of those
1515 // then we're not going to be able to do anything.
1516 LScopes.initialize(*MF);
1517 if (LScopes.empty())
1520 assert(UserVariables.empty() && DbgValues.empty() && "Maps weren't cleaned");
1522 // Make sure that each lexical scope will have a begin/end label.
1523 identifyScopeMarkers();
1525 // Set DwarfDwarfCompileUnitID in MCContext to the Compile Unit this function
1526 // belongs to so that we add to the correct per-cu line table in the
1528 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1529 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1530 assert(TheCU && "Unable to find compile unit!");
1531 if (Asm->OutStreamer.hasRawTextSupport())
1532 // Use a single line table if we are generating assembly.
1533 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1535 Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID());
1537 // Check the current section against the standard text section. If different
1538 // keep track so that we will know when we're emitting functions into multiple
1540 if (Asm->getObjFileLowering().getTextSection() != Asm->getCurrentSection())
1541 UsedNonDefaultText = true;
1543 // Emit a label for the function so that we have a beginning address.
1544 FunctionBeginSym = Asm->GetTempSymbol("func_begin", Asm->getFunctionNumber());
1545 // Assumes in correct section after the entry point.
1546 Asm->OutStreamer.EmitLabel(FunctionBeginSym);
1548 const TargetRegisterInfo *TRI = Asm->TM.getRegisterInfo();
1549 // LiveUserVar - Map physreg numbers to the MDNode they contain.
1550 std::vector<const MDNode *> LiveUserVar(TRI->getNumRegs());
1552 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end(); I != E;
1554 bool AtBlockEntry = true;
1555 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
1557 const MachineInstr *MI = II;
1559 if (MI->isDebugValue()) {
1560 assert(MI->getNumOperands() > 1 && "Invalid machine instruction!");
1562 // Keep track of user variables.
1564 MI->getOperand(MI->getNumOperands() - 1).getMetadata();
1566 // Variable is in a register, we need to check for clobbers.
1567 if (isDbgValueInDefinedReg(MI))
1568 LiveUserVar[MI->getOperand(0).getReg()] = Var;
1570 // Check the history of this variable.
1571 SmallVectorImpl<const MachineInstr *> &History = DbgValues[Var];
1572 if (History.empty()) {
1573 UserVariables.push_back(Var);
1574 // The first mention of a function argument gets the FunctionBeginSym
1575 // label, so arguments are visible when breaking at function entry.
1577 if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable &&
1578 getDISubprogram(DV.getContext()).describes(MF->getFunction()))
1579 LabelsBeforeInsn[MI] = FunctionBeginSym;
1581 // We have seen this variable before. Try to coalesce DBG_VALUEs.
1582 const MachineInstr *Prev = History.back();
1583 if (Prev->isDebugValue()) {
1584 // Coalesce identical entries at the end of History.
1585 if (History.size() >= 2 &&
1586 Prev->isIdenticalTo(History[History.size() - 2])) {
1587 DEBUG(dbgs() << "Coalescing identical DBG_VALUE entries:\n"
1588 << "\t" << *Prev << "\t"
1589 << *History[History.size() - 2] << "\n");
1593 // Terminate old register assignments that don't reach MI;
1594 MachineFunction::const_iterator PrevMBB = Prev->getParent();
1595 if (PrevMBB != I && (!AtBlockEntry || std::next(PrevMBB) != I) &&
1596 isDbgValueInDefinedReg(Prev)) {
1597 // Previous register assignment needs to terminate at the end of
1599 MachineBasicBlock::const_iterator LastMI =
1600 PrevMBB->getLastNonDebugInstr();
1601 if (LastMI == PrevMBB->end()) {
1602 // Drop DBG_VALUE for empty range.
1603 DEBUG(dbgs() << "Dropping DBG_VALUE for empty range:\n"
1604 << "\t" << *Prev << "\n");
1606 } else if (std::next(PrevMBB) != PrevMBB->getParent()->end())
1607 // Terminate after LastMI.
1608 History.push_back(LastMI);
1612 History.push_back(MI);
1614 // Not a DBG_VALUE instruction.
1616 AtBlockEntry = false;
1618 // First known non-DBG_VALUE and non-frame setup location marks
1619 // the beginning of the function body.
1620 if (!MI->getFlag(MachineInstr::FrameSetup) &&
1621 (PrologEndLoc.isUnknown() && !MI->getDebugLoc().isUnknown()))
1622 PrologEndLoc = MI->getDebugLoc();
1624 // Check if the instruction clobbers any registers with debug vars.
1625 for (MachineInstr::const_mop_iterator MOI = MI->operands_begin(),
1626 MOE = MI->operands_end();
1627 MOI != MOE; ++MOI) {
1628 if (!MOI->isReg() || !MOI->isDef() || !MOI->getReg())
1630 for (MCRegAliasIterator AI(MOI->getReg(), TRI, true); AI.isValid();
1633 const MDNode *Var = LiveUserVar[Reg];
1636 // Reg is now clobbered.
1637 LiveUserVar[Reg] = 0;
1639 // Was MD last defined by a DBG_VALUE referring to Reg?
1640 DbgValueHistoryMap::iterator HistI = DbgValues.find(Var);
1641 if (HistI == DbgValues.end())
1643 SmallVectorImpl<const MachineInstr *> &History = HistI->second;
1644 if (History.empty())
1646 const MachineInstr *Prev = History.back();
1647 // Sanity-check: Register assignments are terminated at the end of
1649 if (!Prev->isDebugValue() || Prev->getParent() != MI->getParent())
1651 // Is the variable still in Reg?
1652 if (!isDbgValueInDefinedReg(Prev) ||
1653 Prev->getOperand(0).getReg() != Reg)
1655 // Var is clobbered. Make sure the next instruction gets a label.
1656 History.push_back(MI);
1663 for (DbgValueHistoryMap::iterator I = DbgValues.begin(), E = DbgValues.end();
1665 SmallVectorImpl<const MachineInstr *> &History = I->second;
1666 if (History.empty())
1669 // Make sure the final register assignments are terminated.
1670 const MachineInstr *Prev = History.back();
1671 if (Prev->isDebugValue() && isDbgValueInDefinedReg(Prev)) {
1672 const MachineBasicBlock *PrevMBB = Prev->getParent();
1673 MachineBasicBlock::const_iterator LastMI =
1674 PrevMBB->getLastNonDebugInstr();
1675 if (LastMI == PrevMBB->end())
1676 // Drop DBG_VALUE for empty range.
1678 else if (PrevMBB != &PrevMBB->getParent()->back()) {
1679 // Terminate after LastMI.
1680 History.push_back(LastMI);
1683 // Request labels for the full history.
1684 for (unsigned i = 0, e = History.size(); i != e; ++i) {
1685 const MachineInstr *MI = History[i];
1686 if (MI->isDebugValue())
1687 requestLabelBeforeInsn(MI);
1689 requestLabelAfterInsn(MI);
1693 PrevInstLoc = DebugLoc();
1694 PrevLabel = FunctionBeginSym;
1696 // Record beginning of function.
1697 if (!PrologEndLoc.isUnknown()) {
1698 DebugLoc FnStartDL =
1699 PrologEndLoc.getFnDebugLoc(MF->getFunction()->getContext());
1701 FnStartDL.getLine(), FnStartDL.getCol(),
1702 FnStartDL.getScope(MF->getFunction()->getContext()),
1703 // We'd like to list the prologue as "not statements" but GDB behaves
1704 // poorly if we do that. Revisit this with caution/GDB (7.5+) testing.
1705 DWARF2_FLAG_IS_STMT);
1709 void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) {
1710 SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS];
1711 DIVariable DV = Var->getVariable();
1712 // Variables with positive arg numbers are parameters.
1713 if (unsigned ArgNum = DV.getArgNumber()) {
1714 // Keep all parameters in order at the start of the variable list to ensure
1715 // function types are correct (no out-of-order parameters)
1717 // This could be improved by only doing it for optimized builds (unoptimized
1718 // builds have the right order to begin with), searching from the back (this
1719 // would catch the unoptimized case quickly), or doing a binary search
1720 // rather than linear search.
1721 SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin();
1722 while (I != Vars.end()) {
1723 unsigned CurNum = (*I)->getVariable().getArgNumber();
1724 // A local (non-parameter) variable has been found, insert immediately
1728 // A later indexed parameter has been found, insert immediately before it.
1729 if (CurNum > ArgNum)
1733 Vars.insert(I, Var);
1737 Vars.push_back(Var);
1740 // Gather and emit post-function debug information.
1741 void DwarfDebug::endFunction(const MachineFunction *MF) {
1742 // Every beginFunction(MF) call should be followed by an endFunction(MF) call,
1743 // though the beginFunction may not be called at all.
1744 // We should handle both cases.
1748 assert(CurFn == MF);
1751 if (!MMI->hasDebugInfo() || LScopes.empty()) {
1756 // Define end label for subprogram.
1757 FunctionEndSym = Asm->GetTempSymbol("func_end", Asm->getFunctionNumber());
1758 // Assumes in correct section after the entry point.
1759 Asm->OutStreamer.EmitLabel(FunctionEndSym);
1761 // Set DwarfDwarfCompileUnitID in MCContext to default value.
1762 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1764 SmallPtrSet<const MDNode *, 16> ProcessedVars;
1765 collectVariableInfo(ProcessedVars);
1767 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1768 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1769 assert(TheCU && "Unable to find compile unit!");
1771 // Construct abstract scopes.
1772 ArrayRef<LexicalScope *> AList = LScopes.getAbstractScopesList();
1773 for (unsigned i = 0, e = AList.size(); i != e; ++i) {
1774 LexicalScope *AScope = AList[i];
1775 DISubprogram SP(AScope->getScopeNode());
1776 if (SP.isSubprogram()) {
1777 // Collect info for variables that were optimized out.
1778 DIArray Variables = SP.getVariables();
1779 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1780 DIVariable DV(Variables.getElement(i));
1781 if (!DV || !DV.isVariable() || !ProcessedVars.insert(DV))
1783 // Check that DbgVariable for DV wasn't created earlier, when
1784 // findAbstractVariable() was called for inlined instance of DV.
1785 LLVMContext &Ctx = DV->getContext();
1786 DIVariable CleanDV = cleanseInlinedVariable(DV, Ctx);
1787 if (AbstractVariables.lookup(CleanDV))
1789 if (LexicalScope *Scope = LScopes.findAbstractScope(DV.getContext()))
1790 addScopeVariable(Scope, new DbgVariable(DV, NULL, this));
1793 if (ProcessedSPNodes.count(AScope->getScopeNode()) == 0)
1794 constructScopeDIE(TheCU, AScope);
1797 DIE *CurFnDIE = constructScopeDIE(TheCU, FnScope);
1798 if (!CurFn->getTarget().Options.DisableFramePointerElim(*CurFn))
1799 TheCU->addFlag(CurFnDIE, dwarf::DW_AT_APPLE_omit_frame_ptr);
1801 // Add the range of this function to the list of ranges for the CU.
1802 RangeSpan Span(FunctionBeginSym, FunctionEndSym);
1803 TheCU->addRange(std::move(Span));
1806 for (ScopeVariablesMap::iterator I = ScopeVariables.begin(),
1807 E = ScopeVariables.end();
1809 DeleteContainerPointers(I->second);
1810 ScopeVariables.clear();
1811 DeleteContainerPointers(CurrentFnArguments);
1812 UserVariables.clear();
1814 AbstractVariables.clear();
1815 LabelsBeforeInsn.clear();
1816 LabelsAfterInsn.clear();
1821 // Register a source line with debug info. Returns the unique label that was
1822 // emitted and which provides correspondence to the source line list.
1823 void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S,
1828 unsigned Discriminator = 0;
1830 DIDescriptor Scope(S);
1832 if (Scope.isCompileUnit()) {
1833 DICompileUnit CU(S);
1834 Fn = CU.getFilename();
1835 Dir = CU.getDirectory();
1836 } else if (Scope.isFile()) {
1838 Fn = F.getFilename();
1839 Dir = F.getDirectory();
1840 } else if (Scope.isSubprogram()) {
1842 Fn = SP.getFilename();
1843 Dir = SP.getDirectory();
1844 } else if (Scope.isLexicalBlockFile()) {
1845 DILexicalBlockFile DBF(S);
1846 Fn = DBF.getFilename();
1847 Dir = DBF.getDirectory();
1848 } else if (Scope.isLexicalBlock()) {
1849 DILexicalBlock DB(S);
1850 Fn = DB.getFilename();
1851 Dir = DB.getDirectory();
1852 Discriminator = DB.getDiscriminator();
1854 llvm_unreachable("Unexpected scope info");
1856 Src = getOrCreateSourceID(
1857 Fn, Dir, Asm->OutStreamer.getContext().getDwarfCompileUnitID());
1859 Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0,
1863 //===----------------------------------------------------------------------===//
1865 //===----------------------------------------------------------------------===//
1867 // Compute the size and offset of a DIE. The offset is relative to start of the
1868 // CU. It returns the offset after laying out the DIE.
1869 unsigned DwarfFile::computeSizeAndOffset(DIE *Die, unsigned Offset) {
1870 // Get the children.
1871 const std::vector<DIE *> &Children = Die->getChildren();
1873 // Record the abbreviation.
1874 assignAbbrevNumber(Die->getAbbrev());
1876 // Get the abbreviation for this DIE.
1877 const DIEAbbrev &Abbrev = Die->getAbbrev();
1880 Die->setOffset(Offset);
1882 // Start the size with the size of abbreviation code.
1883 Offset += getULEB128Size(Die->getAbbrevNumber());
1885 const SmallVectorImpl<DIEValue *> &Values = Die->getValues();
1886 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
1888 // Size the DIE attribute values.
1889 for (unsigned i = 0, N = Values.size(); i < N; ++i)
1890 // Size attribute value.
1891 Offset += Values[i]->SizeOf(Asm, AbbrevData[i].getForm());
1893 // Size the DIE children if any.
1894 if (!Children.empty()) {
1895 assert(Abbrev.getChildrenFlag() == dwarf::DW_CHILDREN_yes &&
1896 "Children flag not set");
1898 for (unsigned j = 0, M = Children.size(); j < M; ++j)
1899 Offset = computeSizeAndOffset(Children[j], Offset);
1901 // End of children marker.
1902 Offset += sizeof(int8_t);
1905 Die->setSize(Offset - Die->getOffset());
1909 // Compute the size and offset for each DIE.
1910 void DwarfFile::computeSizeAndOffsets() {
1911 // Offset from the first CU in the debug info section is 0 initially.
1912 unsigned SecOffset = 0;
1914 // Iterate over each compile unit and set the size and offsets for each
1915 // DIE within each compile unit. All offsets are CU relative.
1916 for (SmallVectorImpl<DwarfUnit *>::const_iterator I = CUs.begin(),
1919 (*I)->setDebugInfoOffset(SecOffset);
1921 // CU-relative offset is reset to 0 here.
1922 unsigned Offset = sizeof(int32_t) + // Length of Unit Info
1923 (*I)->getHeaderSize(); // Unit-specific headers
1925 // EndOffset here is CU-relative, after laying out
1926 // all of the CU DIE.
1927 unsigned EndOffset = computeSizeAndOffset((*I)->getUnitDie(), Offset);
1928 SecOffset += EndOffset;
1932 // Emit initial Dwarf sections with a label at the start of each one.
1933 void DwarfDebug::emitSectionLabels() {
1934 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
1936 // Dwarf sections base addresses.
1937 DwarfInfoSectionSym =
1938 emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info");
1939 if (useSplitDwarf())
1940 DwarfInfoDWOSectionSym =
1941 emitSectionSym(Asm, TLOF.getDwarfInfoDWOSection(), "section_info_dwo");
1942 DwarfAbbrevSectionSym =
1943 emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev");
1944 if (useSplitDwarf())
1945 DwarfAbbrevDWOSectionSym = emitSectionSym(
1946 Asm, TLOF.getDwarfAbbrevDWOSection(), "section_abbrev_dwo");
1947 if (GenerateARangeSection)
1948 emitSectionSym(Asm, TLOF.getDwarfARangesSection());
1950 DwarfLineSectionSym =
1951 emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line");
1952 emitSectionSym(Asm, TLOF.getDwarfLocSection());
1953 if (GenerateGnuPubSections) {
1954 DwarfGnuPubNamesSectionSym =
1955 emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection());
1956 DwarfGnuPubTypesSectionSym =
1957 emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection());
1958 } else if (HasDwarfPubSections) {
1959 emitSectionSym(Asm, TLOF.getDwarfPubNamesSection());
1960 emitSectionSym(Asm, TLOF.getDwarfPubTypesSection());
1963 DwarfStrSectionSym =
1964 emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string");
1965 if (useSplitDwarf()) {
1966 DwarfStrDWOSectionSym =
1967 emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string");
1968 DwarfAddrSectionSym =
1969 emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec");
1971 DwarfDebugRangeSectionSym =
1972 emitSectionSym(Asm, TLOF.getDwarfRangesSection(), "debug_range");
1974 DwarfDebugLocSectionSym =
1975 emitSectionSym(Asm, TLOF.getDwarfLocSection(), "section_debug_loc");
1978 // Recursively emits a debug information entry.
1979 void DwarfDebug::emitDIE(DIE *Die) {
1980 // Get the abbreviation for this DIE.
1981 const DIEAbbrev &Abbrev = Die->getAbbrev();
1983 // Emit the code (index) for the abbreviation.
1984 if (Asm->isVerbose())
1985 Asm->OutStreamer.AddComment("Abbrev [" + Twine(Abbrev.getNumber()) +
1986 "] 0x" + Twine::utohexstr(Die->getOffset()) +
1987 ":0x" + Twine::utohexstr(Die->getSize()) + " " +
1988 dwarf::TagString(Abbrev.getTag()));
1989 Asm->EmitULEB128(Abbrev.getNumber());
1991 const SmallVectorImpl<DIEValue *> &Values = Die->getValues();
1992 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
1994 // Emit the DIE attribute values.
1995 for (unsigned i = 0, N = Values.size(); i < N; ++i) {
1996 dwarf::Attribute Attr = AbbrevData[i].getAttribute();
1997 dwarf::Form Form = AbbrevData[i].getForm();
1998 assert(Form && "Too many attributes for DIE (check abbreviation)");
2000 if (Asm->isVerbose())
2001 Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr));
2004 case dwarf::DW_AT_abstract_origin:
2005 case dwarf::DW_AT_type:
2006 case dwarf::DW_AT_friend:
2007 case dwarf::DW_AT_specification:
2008 case dwarf::DW_AT_import:
2009 case dwarf::DW_AT_containing_type: {
2010 DIEEntry *E = cast<DIEEntry>(Values[i]);
2011 DIE *Origin = E->getEntry();
2012 unsigned Addr = Origin->getOffset();
2013 if (Form == dwarf::DW_FORM_ref_addr) {
2014 assert(!useSplitDwarf() && "TODO: dwo files can't have relocations.");
2015 // For DW_FORM_ref_addr, output the offset from beginning of debug info
2016 // section. Origin->getOffset() returns the offset from start of the
2018 DwarfCompileUnit *CU = CUDieMap.lookup(Origin->getUnit());
2019 assert(CU && "CUDie should belong to a CU.");
2020 Addr += CU->getDebugInfoOffset();
2021 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections())
2022 Asm->EmitLabelPlusOffset(CU->getSectionSym(), Addr,
2023 DIEEntry::getRefAddrSize(Asm));
2025 Asm->EmitLabelOffsetDifference(CU->getSectionSym(), Addr,
2026 CU->getSectionSym(),
2027 DIEEntry::getRefAddrSize(Asm));
2029 // Make sure Origin belong to the same CU.
2030 assert(Die->getUnit() == Origin->getUnit() &&
2031 "The referenced DIE should belong to the same CU in ref4");
2032 Asm->EmitInt32(Addr);
2036 case dwarf::DW_AT_location: {
2037 if (DIELabel *L = dyn_cast<DIELabel>(Values[i])) {
2038 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections())
2039 Asm->EmitSectionOffset(L->getValue(), DwarfDebugLocSectionSym);
2041 Asm->EmitLabelDifference(L->getValue(), DwarfDebugLocSectionSym, 4);
2043 Values[i]->EmitValue(Asm, Form);
2047 case dwarf::DW_AT_accessibility: {
2048 if (Asm->isVerbose()) {
2049 DIEInteger *V = cast<DIEInteger>(Values[i]);
2050 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(V->getValue()));
2052 Values[i]->EmitValue(Asm, Form);
2056 // Emit an attribute using the defined form.
2057 Values[i]->EmitValue(Asm, Form);
2062 // Emit the DIE children if any.
2063 if (Abbrev.getChildrenFlag() == dwarf::DW_CHILDREN_yes) {
2064 const std::vector<DIE *> &Children = Die->getChildren();
2066 for (unsigned j = 0, M = Children.size(); j < M; ++j)
2067 emitDIE(Children[j]);
2069 Asm->OutStreamer.AddComment("End Of Children Mark");
2074 // Emit the various dwarf units to the unit section USection with
2075 // the abbreviations going into ASection.
2076 void DwarfFile::emitUnits(DwarfDebug *DD, const MCSection *ASection,
2077 const MCSymbol *ASectionSym) {
2078 for (SmallVectorImpl<DwarfUnit *>::iterator I = CUs.begin(), E = CUs.end();
2080 DwarfUnit *TheU = *I;
2081 DIE *Die = TheU->getUnitDie();
2082 const MCSection *USection = TheU->getSection();
2083 Asm->OutStreamer.SwitchSection(USection);
2085 // Emit the compile units header.
2086 Asm->OutStreamer.EmitLabel(TheU->getLabelBegin());
2088 // Emit size of content not including length itself
2089 Asm->OutStreamer.AddComment("Length of Unit");
2090 Asm->EmitInt32(TheU->getHeaderSize() + Die->getSize());
2092 TheU->emitHeader(ASection, ASectionSym);
2095 Asm->OutStreamer.EmitLabel(TheU->getLabelEnd());
2099 // Emit the debug info section.
2100 void DwarfDebug::emitDebugInfo() {
2101 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
2103 Holder.emitUnits(this, Asm->getObjFileLowering().getDwarfAbbrevSection(),
2104 DwarfAbbrevSectionSym);
2107 // Emit the abbreviation section.
2108 void DwarfDebug::emitAbbreviations() {
2109 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
2111 Holder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection());
2114 void DwarfFile::emitAbbrevs(const MCSection *Section) {
2115 // Check to see if it is worth the effort.
2116 if (!Abbreviations.empty()) {
2117 // Start the debug abbrev section.
2118 Asm->OutStreamer.SwitchSection(Section);
2120 // For each abbrevation.
2121 for (unsigned i = 0, N = Abbreviations.size(); i < N; ++i) {
2122 // Get abbreviation data
2123 const DIEAbbrev *Abbrev = Abbreviations[i];
2125 // Emit the abbrevations code (base 1 index.)
2126 Asm->EmitULEB128(Abbrev->getNumber(), "Abbreviation Code");
2128 // Emit the abbreviations data.
2132 // Mark end of abbreviations.
2133 Asm->EmitULEB128(0, "EOM(3)");
2137 // Emit the last address of the section and the end of the line matrix.
2138 void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) {
2139 // Define last address of section.
2140 Asm->OutStreamer.AddComment("Extended Op");
2143 Asm->OutStreamer.AddComment("Op size");
2144 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1);
2145 Asm->OutStreamer.AddComment("DW_LNE_set_address");
2146 Asm->EmitInt8(dwarf::DW_LNE_set_address);
2148 Asm->OutStreamer.AddComment("Section end label");
2150 Asm->OutStreamer.EmitSymbolValue(
2151 Asm->GetTempSymbol("section_end", SectionEnd),
2152 Asm->getDataLayout().getPointerSize());
2154 // Mark end of matrix.
2155 Asm->OutStreamer.AddComment("DW_LNE_end_sequence");
2161 // Emit visible names into a hashed accelerator table section.
2162 void DwarfDebug::emitAccelNames() {
2164 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, dwarf::DW_FORM_data4));
2165 for (SmallVectorImpl<DwarfUnit *>::const_iterator I = getUnits().begin(),
2166 E = getUnits().end();
2168 DwarfUnit *TheU = *I;
2169 const StringMap<std::vector<const DIE *> > &Names = TheU->getAccelNames();
2170 for (StringMap<std::vector<const DIE *> >::const_iterator
2174 StringRef Name = GI->getKey();
2175 const std::vector<const DIE *> &Entities = GI->second;
2176 for (std::vector<const DIE *>::const_iterator DI = Entities.begin(),
2177 DE = Entities.end();
2179 AT.AddName(Name, *DI);
2183 AT.FinalizeTable(Asm, "Names");
2184 Asm->OutStreamer.SwitchSection(
2185 Asm->getObjFileLowering().getDwarfAccelNamesSection());
2186 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin");
2187 Asm->OutStreamer.EmitLabel(SectionBegin);
2189 // Emit the full data.
2190 AT.Emit(Asm, SectionBegin, &InfoHolder);
2193 // Emit objective C classes and categories into a hashed accelerator table
2195 void DwarfDebug::emitAccelObjC() {
2197 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, dwarf::DW_FORM_data4));
2198 for (SmallVectorImpl<DwarfUnit *>::const_iterator I = getUnits().begin(),
2199 E = getUnits().end();
2201 DwarfUnit *TheU = *I;
2202 const StringMap<std::vector<const DIE *> > &Names = TheU->getAccelObjC();
2203 for (StringMap<std::vector<const DIE *> >::const_iterator
2207 StringRef Name = GI->getKey();
2208 const std::vector<const DIE *> &Entities = GI->second;
2209 for (std::vector<const DIE *>::const_iterator DI = Entities.begin(),
2210 DE = Entities.end();
2212 AT.AddName(Name, *DI);
2216 AT.FinalizeTable(Asm, "ObjC");
2217 Asm->OutStreamer.SwitchSection(
2218 Asm->getObjFileLowering().getDwarfAccelObjCSection());
2219 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin");
2220 Asm->OutStreamer.EmitLabel(SectionBegin);
2222 // Emit the full data.
2223 AT.Emit(Asm, SectionBegin, &InfoHolder);
2226 // Emit namespace dies into a hashed accelerator table.
2227 void DwarfDebug::emitAccelNamespaces() {
2229 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, dwarf::DW_FORM_data4));
2230 for (SmallVectorImpl<DwarfUnit *>::const_iterator I = getUnits().begin(),
2231 E = getUnits().end();
2233 DwarfUnit *TheU = *I;
2234 const StringMap<std::vector<const DIE *> > &Names =
2235 TheU->getAccelNamespace();
2236 for (StringMap<std::vector<const DIE *> >::const_iterator
2240 StringRef Name = GI->getKey();
2241 const std::vector<const DIE *> &Entities = GI->second;
2242 for (std::vector<const DIE *>::const_iterator DI = Entities.begin(),
2243 DE = Entities.end();
2245 AT.AddName(Name, *DI);
2249 AT.FinalizeTable(Asm, "namespac");
2250 Asm->OutStreamer.SwitchSection(
2251 Asm->getObjFileLowering().getDwarfAccelNamespaceSection());
2252 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin");
2253 Asm->OutStreamer.EmitLabel(SectionBegin);
2255 // Emit the full data.
2256 AT.Emit(Asm, SectionBegin, &InfoHolder);
2259 // Emit type dies into a hashed accelerator table.
2260 void DwarfDebug::emitAccelTypes() {
2261 std::vector<DwarfAccelTable::Atom> Atoms;
2263 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, dwarf::DW_FORM_data4));
2265 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_tag, dwarf::DW_FORM_data2));
2267 DwarfAccelTable::Atom(dwarf::DW_ATOM_type_flags, dwarf::DW_FORM_data1));
2268 DwarfAccelTable AT(Atoms);
2269 for (SmallVectorImpl<DwarfUnit *>::const_iterator I = getUnits().begin(),
2270 E = getUnits().end();
2272 DwarfUnit *TheU = *I;
2273 const StringMap<std::vector<std::pair<const DIE *, unsigned> > > &Names =
2274 TheU->getAccelTypes();
2276 std::vector<std::pair<const DIE *, unsigned> > >::const_iterator
2280 StringRef Name = GI->getKey();
2281 const std::vector<std::pair<const DIE *, unsigned> > &Entities =
2283 for (std::vector<std::pair<const DIE *, unsigned> >::const_iterator
2284 DI = Entities.begin(),
2285 DE = Entities.end();
2287 AT.AddName(Name, DI->first, DI->second);
2291 AT.FinalizeTable(Asm, "types");
2292 Asm->OutStreamer.SwitchSection(
2293 Asm->getObjFileLowering().getDwarfAccelTypesSection());
2294 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin");
2295 Asm->OutStreamer.EmitLabel(SectionBegin);
2297 // Emit the full data.
2298 AT.Emit(Asm, SectionBegin, &InfoHolder);
2301 // Public name handling.
2302 // The format for the various pubnames:
2304 // dwarf pubnames - offset/name pairs where the offset is the offset into the CU
2305 // for the DIE that is named.
2307 // gnu pubnames - offset/index value/name tuples where the offset is the offset
2308 // into the CU and the index value is computed according to the type of value
2309 // for the DIE that is named.
2311 // For type units the offset is the offset of the skeleton DIE. For split dwarf
2312 // it's the offset within the debug_info/debug_types dwo section, however, the
2313 // reference in the pubname header doesn't change.
2315 /// computeIndexValue - Compute the gdb index value for the DIE and CU.
2316 static dwarf::PubIndexEntryDescriptor computeIndexValue(DwarfUnit *CU,
2318 dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC;
2320 // We could have a specification DIE that has our most of our knowledge,
2321 // look for that now.
2322 DIEValue *SpecVal = Die->findAttribute(dwarf::DW_AT_specification);
2324 DIE *SpecDIE = cast<DIEEntry>(SpecVal)->getEntry();
2325 if (SpecDIE->findAttribute(dwarf::DW_AT_external))
2326 Linkage = dwarf::GIEL_EXTERNAL;
2327 } else if (Die->findAttribute(dwarf::DW_AT_external))
2328 Linkage = dwarf::GIEL_EXTERNAL;
2330 switch (Die->getTag()) {
2331 case dwarf::DW_TAG_class_type:
2332 case dwarf::DW_TAG_structure_type:
2333 case dwarf::DW_TAG_union_type:
2334 case dwarf::DW_TAG_enumeration_type:
2335 return dwarf::PubIndexEntryDescriptor(
2336 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus
2337 ? dwarf::GIEL_STATIC
2338 : dwarf::GIEL_EXTERNAL);
2339 case dwarf::DW_TAG_typedef:
2340 case dwarf::DW_TAG_base_type:
2341 case dwarf::DW_TAG_subrange_type:
2342 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC);
2343 case dwarf::DW_TAG_namespace:
2344 return dwarf::GIEK_TYPE;
2345 case dwarf::DW_TAG_subprogram:
2346 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage);
2347 case dwarf::DW_TAG_constant:
2348 case dwarf::DW_TAG_variable:
2349 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage);
2350 case dwarf::DW_TAG_enumerator:
2351 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE,
2352 dwarf::GIEL_STATIC);
2354 return dwarf::GIEK_NONE;
2358 /// emitDebugPubNames - Emit visible names into a debug pubnames section.
2360 void DwarfDebug::emitDebugPubNames(bool GnuStyle) {
2361 const MCSection *PSec =
2362 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection()
2363 : Asm->getObjFileLowering().getDwarfPubNamesSection();
2365 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
2366 const SmallVectorImpl<DwarfUnit *> &Units = Holder.getUnits();
2367 for (unsigned i = 0; i != Units.size(); ++i) {
2368 DwarfUnit *TheU = Units[i];
2369 unsigned ID = TheU->getUniqueID();
2371 // Start the dwarf pubnames section.
2372 Asm->OutStreamer.SwitchSection(PSec);
2374 // Emit a label so we can reference the beginning of this pubname section.
2376 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("gnu_pubnames", ID));
2379 Asm->OutStreamer.AddComment("Length of Public Names Info");
2380 MCSymbol *BeginLabel = Asm->GetTempSymbol("pubnames_begin", ID);
2381 MCSymbol *EndLabel = Asm->GetTempSymbol("pubnames_end", ID);
2382 Asm->EmitLabelDifference(EndLabel, BeginLabel, 4);
2384 Asm->OutStreamer.EmitLabel(BeginLabel);
2386 Asm->OutStreamer.AddComment("DWARF Version");
2387 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION);
2389 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info");
2390 Asm->EmitSectionOffset(TheU->getLabelBegin(), TheU->getSectionSym());
2392 Asm->OutStreamer.AddComment("Compilation Unit Length");
2393 Asm->EmitLabelDifference(TheU->getLabelEnd(), TheU->getLabelBegin(), 4);
2395 // Emit the pubnames for this compilation unit.
2396 const StringMap<const DIE *> &Globals = getUnits()[ID]->getGlobalNames();
2397 for (StringMap<const DIE *>::const_iterator GI = Globals.begin(),
2400 const char *Name = GI->getKeyData();
2401 const DIE *Entity = GI->second;
2403 Asm->OutStreamer.AddComment("DIE offset");
2404 Asm->EmitInt32(Entity->getOffset());
2407 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheU, Entity);
2408 Asm->OutStreamer.AddComment(
2409 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " +
2410 dwarf::GDBIndexEntryLinkageString(Desc.Linkage));
2411 Asm->EmitInt8(Desc.toBits());
2414 Asm->OutStreamer.AddComment("External Name");
2415 Asm->OutStreamer.EmitBytes(StringRef(Name, GI->getKeyLength() + 1));
2418 Asm->OutStreamer.AddComment("End Mark");
2420 Asm->OutStreamer.EmitLabel(EndLabel);
2424 void DwarfDebug::emitDebugPubTypes(bool GnuStyle) {
2425 const MCSection *PSec =
2426 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection()
2427 : Asm->getObjFileLowering().getDwarfPubTypesSection();
2429 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
2430 const SmallVectorImpl<DwarfUnit *> &Units = Holder.getUnits();
2431 for (unsigned i = 0; i != Units.size(); ++i) {
2432 DwarfUnit *TheU = Units[i];
2433 unsigned ID = TheU->getUniqueID();
2435 // Start the dwarf pubtypes section.
2436 Asm->OutStreamer.SwitchSection(PSec);
2438 // Emit a label so we can reference the beginning of this pubtype section.
2440 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("gnu_pubtypes", ID));
2443 Asm->OutStreamer.AddComment("Length of Public Types Info");
2444 MCSymbol *BeginLabel = Asm->GetTempSymbol("pubtypes_begin", ID);
2445 MCSymbol *EndLabel = Asm->GetTempSymbol("pubtypes_end", ID);
2446 Asm->EmitLabelDifference(EndLabel, BeginLabel, 4);
2448 Asm->OutStreamer.EmitLabel(BeginLabel);
2450 Asm->OutStreamer.AddComment("DWARF Version");
2451 Asm->EmitInt16(dwarf::DW_PUBTYPES_VERSION);
2453 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info");
2454 Asm->EmitSectionOffset(TheU->getLabelBegin(), TheU->getSectionSym());
2456 Asm->OutStreamer.AddComment("Compilation Unit Length");
2457 Asm->EmitLabelDifference(TheU->getLabelEnd(), TheU->getLabelBegin(), 4);
2459 // Emit the pubtypes.
2460 const StringMap<const DIE *> &Globals = getUnits()[ID]->getGlobalTypes();
2461 for (StringMap<const DIE *>::const_iterator GI = Globals.begin(),
2464 const char *Name = GI->getKeyData();
2465 const DIE *Entity = GI->second;
2467 Asm->OutStreamer.AddComment("DIE offset");
2468 Asm->EmitInt32(Entity->getOffset());
2471 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheU, Entity);
2472 Asm->OutStreamer.AddComment(
2473 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " +
2474 dwarf::GDBIndexEntryLinkageString(Desc.Linkage));
2475 Asm->EmitInt8(Desc.toBits());
2478 Asm->OutStreamer.AddComment("External Name");
2480 // Emit the name with a terminating null byte.
2481 Asm->OutStreamer.EmitBytes(StringRef(Name, GI->getKeyLength() + 1));
2484 Asm->OutStreamer.AddComment("End Mark");
2486 Asm->OutStreamer.EmitLabel(EndLabel);
2490 // Emit strings into a string section.
2491 void DwarfFile::emitStrings(const MCSection *StrSection,
2492 const MCSection *OffsetSection = NULL,
2493 const MCSymbol *StrSecSym = NULL) {
2495 if (StringPool.empty())
2498 // Start the dwarf str section.
2499 Asm->OutStreamer.SwitchSection(StrSection);
2501 // Get all of the string pool entries and put them in an array by their ID so
2502 // we can sort them.
2504 std::pair<unsigned, StringMapEntry<std::pair<MCSymbol *, unsigned> > *>,
2507 for (StringMap<std::pair<MCSymbol *, unsigned> >::iterator
2508 I = StringPool.begin(),
2509 E = StringPool.end();
2511 Entries.push_back(std::make_pair(I->second.second, &*I));
2513 array_pod_sort(Entries.begin(), Entries.end());
2515 for (unsigned i = 0, e = Entries.size(); i != e; ++i) {
2516 // Emit a label for reference from debug information entries.
2517 Asm->OutStreamer.EmitLabel(Entries[i].second->getValue().first);
2519 // Emit the string itself with a terminating null byte.
2520 Asm->OutStreamer.EmitBytes(
2521 StringRef(Entries[i].second->getKeyData(),
2522 Entries[i].second->getKeyLength() + 1));
2525 // If we've got an offset section go ahead and emit that now as well.
2526 if (OffsetSection) {
2527 Asm->OutStreamer.SwitchSection(OffsetSection);
2528 unsigned offset = 0;
2529 unsigned size = 4; // FIXME: DWARF64 is 8.
2530 for (unsigned i = 0, e = Entries.size(); i != e; ++i) {
2531 Asm->OutStreamer.EmitIntValue(offset, size);
2532 offset += Entries[i].second->getKeyLength() + 1;
2537 // Emit addresses into the section given.
2538 void DwarfFile::emitAddresses(const MCSection *AddrSection) {
2540 if (AddressPool.empty())
2543 // Start the dwarf addr section.
2544 Asm->OutStreamer.SwitchSection(AddrSection);
2546 // Order the address pool entries by ID
2547 SmallVector<const MCExpr *, 64> Entries(AddressPool.size());
2549 for (AddrPool::iterator I = AddressPool.begin(), E = AddressPool.end();
2551 Entries[I->second.Number] =
2553 ? Asm->getObjFileLowering().getDebugThreadLocalSymbol(I->first)
2554 : MCSymbolRefExpr::Create(I->first, Asm->OutContext);
2556 for (unsigned i = 0, e = Entries.size(); i != e; ++i)
2557 Asm->OutStreamer.EmitValue(Entries[i],
2558 Asm->getDataLayout().getPointerSize());
2561 // Emit visible names into a debug str section.
2562 void DwarfDebug::emitDebugStr() {
2563 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
2564 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection());
2567 // Emit locations into the debug loc section.
2568 void DwarfDebug::emitDebugLoc() {
2569 if (DotDebugLocEntries.empty())
2572 for (SmallVectorImpl<DotDebugLocEntry>::iterator
2573 I = DotDebugLocEntries.begin(),
2574 E = DotDebugLocEntries.end();
2576 DotDebugLocEntry &Entry = *I;
2577 if (I + 1 != DotDebugLocEntries.end())
2581 // Start the dwarf loc section.
2582 Asm->OutStreamer.SwitchSection(
2583 Asm->getObjFileLowering().getDwarfLocSection());
2584 unsigned char Size = Asm->getDataLayout().getPointerSize();
2585 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("debug_loc", 0));
2587 for (SmallVectorImpl<DotDebugLocEntry>::iterator
2588 I = DotDebugLocEntries.begin(),
2589 E = DotDebugLocEntries.end();
2590 I != E; ++I, ++index) {
2591 DotDebugLocEntry &Entry = *I;
2592 if (Entry.isMerged())
2594 if (Entry.isEmpty()) {
2595 Asm->OutStreamer.EmitIntValue(0, Size);
2596 Asm->OutStreamer.EmitIntValue(0, Size);
2597 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("debug_loc", index));
2599 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size);
2600 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size);
2601 DIVariable DV(Entry.getVariable());
2602 Asm->OutStreamer.AddComment("Loc expr size");
2603 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol();
2604 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol();
2605 Asm->EmitLabelDifference(end, begin, 2);
2606 Asm->OutStreamer.EmitLabel(begin);
2607 if (Entry.isInt()) {
2608 DIBasicType BTy(DV.getType());
2609 if (BTy.Verify() && (BTy.getEncoding() == dwarf::DW_ATE_signed ||
2610 BTy.getEncoding() == dwarf::DW_ATE_signed_char)) {
2611 Asm->OutStreamer.AddComment("DW_OP_consts");
2612 Asm->EmitInt8(dwarf::DW_OP_consts);
2613 Asm->EmitSLEB128(Entry.getInt());
2615 Asm->OutStreamer.AddComment("DW_OP_constu");
2616 Asm->EmitInt8(dwarf::DW_OP_constu);
2617 Asm->EmitULEB128(Entry.getInt());
2619 } else if (Entry.isLocation()) {
2620 MachineLocation Loc = Entry.getLoc();
2621 if (!DV.hasComplexAddress())
2623 Asm->EmitDwarfRegOp(Loc, DV.isIndirect());
2625 // Complex address entry.
2626 unsigned N = DV.getNumAddrElements();
2628 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) {
2629 if (Loc.getOffset()) {
2631 Asm->EmitDwarfRegOp(Loc, DV.isIndirect());
2632 Asm->OutStreamer.AddComment("DW_OP_deref");
2633 Asm->EmitInt8(dwarf::DW_OP_deref);
2634 Asm->OutStreamer.AddComment("DW_OP_plus_uconst");
2635 Asm->EmitInt8(dwarf::DW_OP_plus_uconst);
2636 Asm->EmitSLEB128(DV.getAddrElement(1));
2638 // If first address element is OpPlus then emit
2639 // DW_OP_breg + Offset instead of DW_OP_reg + Offset.
2640 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1));
2641 Asm->EmitDwarfRegOp(TLoc, DV.isIndirect());
2645 Asm->EmitDwarfRegOp(Loc, DV.isIndirect());
2648 // Emit remaining complex address elements.
2649 for (; i < N; ++i) {
2650 uint64_t Element = DV.getAddrElement(i);
2651 if (Element == DIBuilder::OpPlus) {
2652 Asm->EmitInt8(dwarf::DW_OP_plus_uconst);
2653 Asm->EmitULEB128(DV.getAddrElement(++i));
2654 } else if (Element == DIBuilder::OpDeref) {
2656 Asm->EmitInt8(dwarf::DW_OP_deref);
2658 llvm_unreachable("unknown Opcode found in complex address");
2662 // else ... ignore constant fp. There is not any good way to
2663 // to represent them here in dwarf.
2664 Asm->OutStreamer.EmitLabel(end);
2669 struct SymbolCUSorter {
2670 SymbolCUSorter(const MCStreamer &s) : Streamer(s) {}
2671 const MCStreamer &Streamer;
2673 bool operator()(const SymbolCU &A, const SymbolCU &B) {
2674 unsigned IA = A.Sym ? Streamer.GetSymbolOrder(A.Sym) : 0;
2675 unsigned IB = B.Sym ? Streamer.GetSymbolOrder(B.Sym) : 0;
2677 // Symbols with no order assigned should be placed at the end.
2678 // (e.g. section end labels)
2680 IA = (unsigned)(-1);
2682 IB = (unsigned)(-1);
2687 static bool CUSort(const DwarfUnit *A, const DwarfUnit *B) {
2688 return (A->getUniqueID() < B->getUniqueID());
2692 const MCSymbol *Start, *End;
2695 // Emit a debug aranges section, containing a CU lookup for any
2696 // address we can tie back to a CU.
2697 void DwarfDebug::emitDebugARanges() {
2698 // Start the dwarf aranges section.
2699 Asm->OutStreamer.SwitchSection(
2700 Asm->getObjFileLowering().getDwarfARangesSection());
2702 typedef DenseMap<DwarfCompileUnit *, std::vector<ArangeSpan> > SpansType;
2706 // Build a list of sections used.
2707 std::vector<const MCSection *> Sections;
2708 for (SectionMapType::iterator it = SectionMap.begin(); it != SectionMap.end();
2710 const MCSection *Section = it->first;
2711 Sections.push_back(Section);
2714 // Sort the sections into order.
2715 // This is only done to ensure consistent output order across different runs.
2716 std::sort(Sections.begin(), Sections.end(), SectionSort);
2718 // Build a set of address spans, sorted by CU.
2719 for (size_t SecIdx = 0; SecIdx < Sections.size(); SecIdx++) {
2720 const MCSection *Section = Sections[SecIdx];
2721 SmallVector<SymbolCU, 8> &List = SectionMap[Section];
2722 if (List.size() < 2)
2725 // Sort the symbols by offset within the section.
2726 SymbolCUSorter sorter(Asm->OutStreamer);
2727 std::sort(List.begin(), List.end(), sorter);
2729 // If we have no section (e.g. common), just write out
2730 // individual spans for each symbol.
2731 if (Section == NULL) {
2732 for (size_t n = 0; n < List.size(); n++) {
2733 const SymbolCU &Cur = List[n];
2736 Span.Start = Cur.Sym;
2739 Spans[Cur.CU].push_back(Span);
2742 // Build spans between each label.
2743 const MCSymbol *StartSym = List[0].Sym;
2744 for (size_t n = 1; n < List.size(); n++) {
2745 const SymbolCU &Prev = List[n - 1];
2746 const SymbolCU &Cur = List[n];
2748 // Try and build the longest span we can within the same CU.
2749 if (Cur.CU != Prev.CU) {
2751 Span.Start = StartSym;
2753 Spans[Prev.CU].push_back(Span);
2760 unsigned PtrSize = Asm->getDataLayout().getPointerSize();
2762 // Build a list of CUs used.
2763 std::vector<DwarfCompileUnit *> CUs;
2764 for (SpansType::iterator it = Spans.begin(); it != Spans.end(); it++) {
2765 DwarfCompileUnit *CU = it->first;
2769 // Sort the CU list (again, to ensure consistent output order).
2770 std::sort(CUs.begin(), CUs.end(), CUSort);
2772 // Emit an arange table for each CU we used.
2773 for (size_t CUIdx = 0; CUIdx < CUs.size(); CUIdx++) {
2774 DwarfCompileUnit *CU = CUs[CUIdx];
2775 std::vector<ArangeSpan> &List = Spans[CU];
2777 // Emit size of content not including length itself.
2778 unsigned ContentSize =
2779 sizeof(int16_t) + // DWARF ARange version number
2780 sizeof(int32_t) + // Offset of CU in the .debug_info section
2781 sizeof(int8_t) + // Pointer Size (in bytes)
2782 sizeof(int8_t); // Segment Size (in bytes)
2784 unsigned TupleSize = PtrSize * 2;
2786 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple.
2788 OffsetToAlignment(sizeof(int32_t) + ContentSize, TupleSize);
2790 ContentSize += Padding;
2791 ContentSize += (List.size() + 1) * TupleSize;
2793 // For each compile unit, write the list of spans it covers.
2794 Asm->OutStreamer.AddComment("Length of ARange Set");
2795 Asm->EmitInt32(ContentSize);
2796 Asm->OutStreamer.AddComment("DWARF Arange version number");
2797 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION);
2798 Asm->OutStreamer.AddComment("Offset Into Debug Info Section");
2799 Asm->EmitSectionOffset(CU->getLocalLabelBegin(), CU->getLocalSectionSym());
2800 Asm->OutStreamer.AddComment("Address Size (in bytes)");
2801 Asm->EmitInt8(PtrSize);
2802 Asm->OutStreamer.AddComment("Segment Size (in bytes)");
2805 Asm->OutStreamer.EmitFill(Padding, 0xff);
2807 for (unsigned n = 0; n < List.size(); n++) {
2808 const ArangeSpan &Span = List[n];
2809 Asm->EmitLabelReference(Span.Start, PtrSize);
2811 // Calculate the size as being from the span start to it's end.
2813 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize);
2815 // For symbols without an end marker (e.g. common), we
2816 // write a single arange entry containing just that one symbol.
2817 uint64_t Size = SymSize[Span.Start];
2821 Asm->OutStreamer.EmitIntValue(Size, PtrSize);
2825 Asm->OutStreamer.AddComment("ARange terminator");
2826 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2827 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2831 // Emit visible names into a debug ranges section.
2832 void DwarfDebug::emitDebugRanges() {
2833 // Start the dwarf ranges section.
2834 Asm->OutStreamer.SwitchSection(
2835 Asm->getObjFileLowering().getDwarfRangesSection());
2837 // Size for our labels.
2838 unsigned char Size = Asm->getDataLayout().getPointerSize();
2840 // Grab the specific ranges for the compile units in the module.
2841 for (MapVector<const MDNode *, DwarfCompileUnit *>::iterator
2845 DwarfCompileUnit *TheCU = I->second;
2847 // Emit a symbol so we can find the beginning of our ranges.
2848 Asm->OutStreamer.EmitLabel(TheCU->getLabelRange());
2850 // Iterate over the misc ranges for the compile units in the module.
2851 const SmallVectorImpl<RangeSpanList> &RangeLists = TheCU->getRangeLists();
2852 for (SmallVectorImpl<RangeSpanList>::const_iterator I = RangeLists.begin(),
2853 E = RangeLists.end();
2855 const RangeSpanList &List = *I;
2857 // Emit our symbol so we can find the beginning of the range.
2858 Asm->OutStreamer.EmitLabel(List.getSym());
2860 for (SmallVectorImpl<RangeSpan>::const_iterator
2861 RI = List.getRanges().begin(),
2862 RE = List.getRanges().end();
2864 const RangeSpan &Range = *RI;
2865 const MCSymbol *Begin = Range.getStart();
2866 const MCSymbol *End = Range.getEnd();
2867 assert(Begin && "Range without a begin symbol?");
2868 assert(End && "Range without an end symbol?");
2869 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2870 Asm->OutStreamer.EmitSymbolValue(End, Size);
2873 // And terminate the list with two 0 values.
2874 Asm->OutStreamer.EmitIntValue(0, Size);
2875 Asm->OutStreamer.EmitIntValue(0, Size);
2878 // Now emit a range for the CU itself.
2879 if (useCURanges() && TheCU->getRanges().size()) {
2880 Asm->OutStreamer.EmitLabel(
2881 Asm->GetTempSymbol("cu_ranges", TheCU->getUniqueID()));
2882 const SmallVectorImpl<RangeSpan> &Ranges = TheCU->getRanges();
2883 for (uint32_t i = 0, e = Ranges.size(); i != e; ++i) {
2884 RangeSpan Range = Ranges[i];
2885 const MCSymbol *Begin = Range.getStart();
2886 const MCSymbol *End = Range.getEnd();
2887 assert(Begin && "Range without a begin symbol?");
2888 assert(End && "Range without an end symbol?");
2889 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2890 Asm->OutStreamer.EmitSymbolValue(End, Size);
2892 // And terminate the list with two 0 values.
2893 Asm->OutStreamer.EmitIntValue(0, Size);
2894 Asm->OutStreamer.EmitIntValue(0, Size);
2899 // DWARF5 Experimental Separate Dwarf emitters.
2901 void DwarfDebug::initSkeletonUnit(const DwarfUnit *U, DIE *Die,
2903 NewU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name,
2904 U->getCUNode().getSplitDebugFilename());
2906 // Relocate to the beginning of the addr_base section, else 0 for the
2907 // beginning of the one for this compile unit.
2908 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections())
2909 NewU->addSectionLabel(Die, dwarf::DW_AT_GNU_addr_base, DwarfAddrSectionSym);
2911 NewU->addSectionOffset(Die, dwarf::DW_AT_GNU_addr_base, 0);
2913 if (!CompilationDir.empty())
2914 NewU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
2916 addGnuPubAttributes(NewU, Die);
2918 SkeletonHolder.addUnit(NewU);
2921 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list,
2922 // DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id,
2923 // DW_AT_ranges_base, DW_AT_addr_base.
2924 // TODO: Implement DW_AT_ranges_base.
2925 DwarfCompileUnit *DwarfDebug::constructSkeletonCU(const DwarfCompileUnit *CU) {
2927 DIE *Die = new DIE(dwarf::DW_TAG_compile_unit);
2928 DwarfCompileUnit *NewCU = new DwarfCompileUnit(
2929 CU->getUniqueID(), Die, CU->getCUNode(), Asm, this, &SkeletonHolder);
2930 NewCU->initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
2931 DwarfInfoSectionSym);
2933 NewCU->initStmtList(DwarfLineSectionSym);
2935 initSkeletonUnit(CU, Die, NewCU);
2940 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_dwo_name,
2942 DwarfTypeUnit *DwarfDebug::constructSkeletonTU(DwarfTypeUnit *TU) {
2943 DwarfCompileUnit &CU = static_cast<DwarfCompileUnit &>(
2944 *SkeletonHolder.getUnits()[TU->getCU().getUniqueID()]);
2946 DIE *Die = new DIE(dwarf::DW_TAG_type_unit);
2947 DwarfTypeUnit *NewTU =
2948 new DwarfTypeUnit(TU->getUniqueID(), Die, CU, Asm, this, &SkeletonHolder);
2949 NewTU->setTypeSignature(TU->getTypeSignature());
2950 NewTU->setType(NULL);
2952 Asm->getObjFileLowering().getDwarfTypesSection(TU->getTypeSignature()));
2953 CU.applyStmtList(*Die);
2955 initSkeletonUnit(TU, Die, NewTU);
2959 // Emit the .debug_info.dwo section for separated dwarf. This contains the
2960 // compile units that would normally be in debug_info.
2961 void DwarfDebug::emitDebugInfoDWO() {
2962 assert(useSplitDwarf() && "No split dwarf debug info?");
2963 InfoHolder.emitUnits(this,
2964 Asm->getObjFileLowering().getDwarfAbbrevDWOSection(),
2965 DwarfAbbrevDWOSectionSym);
2968 // Emit the .debug_abbrev.dwo section for separated dwarf. This contains the
2969 // abbreviations for the .debug_info.dwo section.
2970 void DwarfDebug::emitDebugAbbrevDWO() {
2971 assert(useSplitDwarf() && "No split dwarf?");
2972 InfoHolder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection());
2975 // Emit the .debug_str.dwo section for separated dwarf. This contains the
2976 // string section and is identical in format to traditional .debug_str
2978 void DwarfDebug::emitDebugStrDWO() {
2979 assert(useSplitDwarf() && "No split dwarf?");
2980 const MCSection *OffSec =
2981 Asm->getObjFileLowering().getDwarfStrOffDWOSection();
2982 const MCSymbol *StrSym = DwarfStrSectionSym;
2983 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(),
2987 void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU,
2988 StringRef Identifier, DIE *RefDie,
2989 DICompositeType CTy) {
2990 // Flag the type unit reference as a declaration so that if it contains
2991 // members (implicit special members, static data member definitions, member
2992 // declarations for definitions in this CU, etc) consumers don't get confused
2993 // and think this is a full definition.
2994 CU.addFlag(RefDie, dwarf::DW_AT_declaration);
2996 const DwarfTypeUnit *&TU = DwarfTypeUnits[CTy];
2998 CU.addDIETypeSignature(RefDie, *TU);
3002 DIE *UnitDie = new DIE(dwarf::DW_TAG_type_unit);
3003 DwarfTypeUnit *NewTU = new DwarfTypeUnit(InfoHolder.getUnits().size(),
3004 UnitDie, CU, Asm, this, &InfoHolder);
3006 InfoHolder.addUnit(NewTU);
3008 NewTU->addUInt(UnitDie, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
3012 Hash.update(Identifier);
3013 // ... take the least significant 8 bytes and return those. Our MD5
3014 // implementation always returns its results in little endian, swap bytes
3016 MD5::MD5Result Result;
3018 uint64_t Signature = *reinterpret_cast<support::ulittle64_t *>(Result + 8);
3019 NewTU->setTypeSignature(Signature);
3020 if (useSplitDwarf())
3021 NewTU->setSkeleton(constructSkeletonTU(NewTU));
3023 CU.applyStmtList(*UnitDie);
3025 NewTU->setType(NewTU->createTypeDIE(CTy));
3029 ? Asm->getObjFileLowering().getDwarfTypesDWOSection(Signature)
3030 : Asm->getObjFileLowering().getDwarfTypesSection(Signature));
3032 CU.addDIETypeSignature(RefDie, *NewTU);