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 #include "ByteStreamer.h"
15 #include "DwarfDebug.h"
18 #include "DwarfUnit.h"
19 #include "llvm/ADT/STLExtras.h"
20 #include "llvm/ADT/Statistic.h"
21 #include "llvm/ADT/StringExtras.h"
22 #include "llvm/ADT/Triple.h"
23 #include "llvm/CodeGen/MachineFunction.h"
24 #include "llvm/CodeGen/MachineModuleInfo.h"
25 #include "llvm/IR/Constants.h"
26 #include "llvm/IR/DIBuilder.h"
27 #include "llvm/IR/DataLayout.h"
28 #include "llvm/IR/DebugInfo.h"
29 #include "llvm/IR/Instructions.h"
30 #include "llvm/IR/Module.h"
31 #include "llvm/IR/ValueHandle.h"
32 #include "llvm/MC/MCAsmInfo.h"
33 #include "llvm/MC/MCSection.h"
34 #include "llvm/MC/MCStreamer.h"
35 #include "llvm/MC/MCSymbol.h"
36 #include "llvm/Support/CommandLine.h"
37 #include "llvm/Support/Debug.h"
38 #include "llvm/Support/Dwarf.h"
39 #include "llvm/Support/ErrorHandling.h"
40 #include "llvm/Support/FormattedStream.h"
41 #include "llvm/Support/LEB128.h"
42 #include "llvm/Support/MD5.h"
43 #include "llvm/Support/Path.h"
44 #include "llvm/Support/Timer.h"
45 #include "llvm/Target/TargetFrameLowering.h"
46 #include "llvm/Target/TargetLoweringObjectFile.h"
47 #include "llvm/Target/TargetMachine.h"
48 #include "llvm/Target/TargetOptions.h"
49 #include "llvm/Target/TargetRegisterInfo.h"
52 #define DEBUG_TYPE "dwarfdebug"
55 DisableDebugInfoPrinting("disable-debug-info-print", cl::Hidden,
56 cl::desc("Disable debug info printing"));
58 static cl::opt<bool> UnknownLocations(
59 "use-unknown-locations", cl::Hidden,
60 cl::desc("Make an absence of debug location information explicit."),
64 GenerateGnuPubSections("generate-gnu-dwarf-pub-sections", cl::Hidden,
65 cl::desc("Generate GNU-style pubnames and pubtypes"),
68 static cl::opt<bool> GenerateARangeSection("generate-arange-section",
70 cl::desc("Generate dwarf aranges"),
74 enum DefaultOnOff { Default, Enable, Disable };
77 static cl::opt<DefaultOnOff>
78 DwarfAccelTables("dwarf-accel-tables", cl::Hidden,
79 cl::desc("Output prototype dwarf accelerator tables."),
80 cl::values(clEnumVal(Default, "Default for platform"),
81 clEnumVal(Enable, "Enabled"),
82 clEnumVal(Disable, "Disabled"), clEnumValEnd),
85 static cl::opt<DefaultOnOff>
86 SplitDwarf("split-dwarf", cl::Hidden,
87 cl::desc("Output DWARF5 split debug info."),
88 cl::values(clEnumVal(Default, "Default for platform"),
89 clEnumVal(Enable, "Enabled"),
90 clEnumVal(Disable, "Disabled"), clEnumValEnd),
93 static cl::opt<DefaultOnOff>
94 DwarfPubSections("generate-dwarf-pub-sections", cl::Hidden,
95 cl::desc("Generate DWARF pubnames and pubtypes sections"),
96 cl::values(clEnumVal(Default, "Default for platform"),
97 clEnumVal(Enable, "Enabled"),
98 clEnumVal(Disable, "Disabled"), clEnumValEnd),
101 static cl::opt<unsigned>
102 DwarfVersionNumber("dwarf-version", cl::Hidden,
103 cl::desc("Generate DWARF for dwarf version."), cl::init(0));
105 static const char *const DWARFGroupName = "DWARF Emission";
106 static const char *const DbgTimerName = "DWARF Debug Writer";
108 //===----------------------------------------------------------------------===//
110 /// resolve - Look in the DwarfDebug map for the MDNode that
111 /// corresponds to the reference.
112 template <typename T> T DbgVariable::resolve(DIRef<T> Ref) const {
113 return DD->resolve(Ref);
116 bool DbgVariable::isBlockByrefVariable() const {
117 assert(Var.isVariable() && "Invalid complex DbgVariable!");
118 return Var.isBlockByrefVariable(DD->getTypeIdentifierMap());
121 DIType DbgVariable::getType() const {
122 DIType Ty = Var.getType().resolve(DD->getTypeIdentifierMap());
123 // FIXME: isBlockByrefVariable should be reformulated in terms of complex
124 // addresses instead.
125 if (Var.isBlockByrefVariable(DD->getTypeIdentifierMap())) {
126 /* Byref variables, in Blocks, are declared by the programmer as
127 "SomeType VarName;", but the compiler creates a
128 __Block_byref_x_VarName struct, and gives the variable VarName
129 either the struct, or a pointer to the struct, as its type. This
130 is necessary for various behind-the-scenes things the compiler
131 needs to do with by-reference variables in blocks.
133 However, as far as the original *programmer* is concerned, the
134 variable should still have type 'SomeType', as originally declared.
136 The following function dives into the __Block_byref_x_VarName
137 struct to find the original type of the variable. This will be
138 passed back to the code generating the type for the Debug
139 Information Entry for the variable 'VarName'. 'VarName' will then
140 have the original type 'SomeType' in its debug information.
142 The original type 'SomeType' will be the type of the field named
143 'VarName' inside the __Block_byref_x_VarName struct.
145 NOTE: In order for this to not completely fail on the debugger
146 side, the Debug Information Entry for the variable VarName needs to
147 have a DW_AT_location that tells the debugger how to unwind through
148 the pointers and __Block_byref_x_VarName struct to find the actual
149 value of the variable. The function addBlockByrefType does this. */
151 uint16_t tag = Ty.getTag();
153 if (tag == dwarf::DW_TAG_pointer_type)
154 subType = resolve(DIDerivedType(Ty).getTypeDerivedFrom());
156 DIArray Elements = DICompositeType(subType).getTypeArray();
157 for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) {
158 DIDerivedType DT(Elements.getElement(i));
159 if (getName() == DT.getName())
160 return (resolve(DT.getTypeDerivedFrom()));
166 static LLVM_CONSTEXPR DwarfAccelTable::Atom TypeAtoms[] = {
167 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, dwarf::DW_FORM_data4),
168 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_tag, dwarf::DW_FORM_data2),
169 DwarfAccelTable::Atom(dwarf::DW_ATOM_type_flags, dwarf::DW_FORM_data1)};
171 DwarfDebug::DwarfDebug(AsmPrinter *A, Module *M)
172 : Asm(A), MMI(Asm->MMI), FirstCU(nullptr), PrevLabel(nullptr),
173 GlobalRangeCount(0), InfoHolder(A, "info_string", DIEValueAllocator),
174 UsedNonDefaultText(false),
175 SkeletonHolder(A, "skel_string", DIEValueAllocator),
176 AccelNames(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset,
177 dwarf::DW_FORM_data4)),
178 AccelObjC(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset,
179 dwarf::DW_FORM_data4)),
180 AccelNamespace(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset,
181 dwarf::DW_FORM_data4)),
182 AccelTypes(TypeAtoms) {
184 DwarfInfoSectionSym = DwarfAbbrevSectionSym = DwarfStrSectionSym = nullptr;
185 DwarfDebugRangeSectionSym = DwarfDebugLocSectionSym = nullptr;
186 DwarfLineSectionSym = nullptr;
187 DwarfAddrSectionSym = nullptr;
188 DwarfAbbrevDWOSectionSym = DwarfStrDWOSectionSym = nullptr;
189 FunctionBeginSym = FunctionEndSym = nullptr;
193 // Turn on accelerator tables for Darwin by default, pubnames by
194 // default for non-Darwin, and handle split dwarf.
195 bool IsDarwin = Triple(A->getTargetTriple()).isOSDarwin();
197 if (DwarfAccelTables == Default)
198 HasDwarfAccelTables = IsDarwin;
200 HasDwarfAccelTables = DwarfAccelTables == Enable;
202 if (SplitDwarf == Default)
203 HasSplitDwarf = false;
205 HasSplitDwarf = SplitDwarf == Enable;
207 if (DwarfPubSections == Default)
208 HasDwarfPubSections = !IsDarwin;
210 HasDwarfPubSections = DwarfPubSections == Enable;
212 DwarfVersion = DwarfVersionNumber ? DwarfVersionNumber
213 : MMI->getModule()->getDwarfVersion();
216 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
221 // Define out of line so we don't have to include DwarfUnit.h in DwarfDebug.h.
222 DwarfDebug::~DwarfDebug() { }
224 // Switch to the specified MCSection and emit an assembler
225 // temporary label to it if SymbolStem is specified.
226 static MCSymbol *emitSectionSym(AsmPrinter *Asm, const MCSection *Section,
227 const char *SymbolStem = nullptr) {
228 Asm->OutStreamer.SwitchSection(Section);
232 MCSymbol *TmpSym = Asm->GetTempSymbol(SymbolStem);
233 Asm->OutStreamer.EmitLabel(TmpSym);
237 static bool isObjCClass(StringRef Name) {
238 return Name.startswith("+") || Name.startswith("-");
241 static bool hasObjCCategory(StringRef Name) {
242 if (!isObjCClass(Name))
245 return Name.find(") ") != StringRef::npos;
248 static void getObjCClassCategory(StringRef In, StringRef &Class,
249 StringRef &Category) {
250 if (!hasObjCCategory(In)) {
251 Class = In.slice(In.find('[') + 1, In.find(' '));
256 Class = In.slice(In.find('[') + 1, In.find('('));
257 Category = In.slice(In.find('[') + 1, In.find(' '));
261 static StringRef getObjCMethodName(StringRef In) {
262 return In.slice(In.find(' ') + 1, In.find(']'));
265 // Helper for sorting sections into a stable output order.
266 static bool SectionSort(const MCSection *A, const MCSection *B) {
267 std::string LA = (A ? A->getLabelBeginName() : "");
268 std::string LB = (B ? B->getLabelBeginName() : "");
272 // Add the various names to the Dwarf accelerator table names.
273 // TODO: Determine whether or not we should add names for programs
274 // that do not have a DW_AT_name or DW_AT_linkage_name field - this
275 // is only slightly different than the lookup of non-standard ObjC names.
276 void DwarfDebug::addSubprogramNames(DISubprogram SP, DIE &Die) {
277 if (!SP.isDefinition())
279 addAccelName(SP.getName(), Die);
281 // If the linkage name is different than the name, go ahead and output
282 // that as well into the name table.
283 if (SP.getLinkageName() != "" && SP.getName() != SP.getLinkageName())
284 addAccelName(SP.getLinkageName(), Die);
286 // If this is an Objective-C selector name add it to the ObjC accelerator
288 if (isObjCClass(SP.getName())) {
289 StringRef Class, Category;
290 getObjCClassCategory(SP.getName(), Class, Category);
291 addAccelObjC(Class, Die);
293 addAccelObjC(Category, Die);
294 // Also add the base method name to the name table.
295 addAccelName(getObjCMethodName(SP.getName()), Die);
299 /// isSubprogramContext - Return true if Context is either a subprogram
300 /// or another context nested inside a subprogram.
301 bool DwarfDebug::isSubprogramContext(const MDNode *Context) {
304 DIDescriptor D(Context);
305 if (D.isSubprogram())
308 return isSubprogramContext(resolve(DIType(Context).getContext()));
312 // Find DIE for the given subprogram and attach appropriate DW_AT_low_pc
313 // and DW_AT_high_pc attributes. If there are global variables in this
314 // scope then create and insert DIEs for these variables.
315 DIE &DwarfDebug::updateSubprogramScopeDIE(DwarfCompileUnit &SPCU,
317 DIE *SPDie = SPCU.getDIE(SP);
319 assert(SPDie && "Unable to find subprogram DIE!");
321 // If we're updating an abstract DIE, then we will be adding the children and
322 // object pointer later on. But what we don't want to do is process the
323 // concrete DIE twice.
324 if (DIE *AbsSPDIE = AbstractSPDies.lookup(SP)) {
325 assert(SPDie == AbsSPDIE);
326 // Pick up abstract subprogram DIE.
327 SPDie = &SPCU.createAndAddDIE(dwarf::DW_TAG_subprogram, SPCU.getUnitDie());
328 SPCU.addDIEEntry(*SPDie, dwarf::DW_AT_abstract_origin, *AbsSPDIE);
331 attachLowHighPC(SPCU, *SPDie, FunctionBeginSym, FunctionEndSym);
333 const TargetRegisterInfo *RI = Asm->TM.getRegisterInfo();
334 MachineLocation Location(RI->getFrameRegister(*Asm->MF));
335 SPCU.addAddress(*SPDie, dwarf::DW_AT_frame_base, Location);
337 // Add name to the name table, we do this here because we're guaranteed
338 // to have concrete versions of our DW_TAG_subprogram nodes.
339 addSubprogramNames(SP, *SPDie);
344 /// Check whether we should create a DIE for the given Scope, return true
345 /// if we don't create a DIE (the corresponding DIE is null).
346 bool DwarfDebug::isLexicalScopeDIENull(LexicalScope *Scope) {
347 if (Scope->isAbstractScope())
350 // We don't create a DIE if there is no Range.
351 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges();
355 if (Ranges.size() > 1)
358 // We don't create a DIE if we have a single Range and the end label
360 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin();
361 MCSymbol *End = getLabelAfterInsn(RI->second);
365 static void addSectionLabel(AsmPrinter &Asm, DwarfUnit &U, DIE &D,
366 dwarf::Attribute A, const MCSymbol *L,
367 const MCSymbol *Sec) {
368 if (Asm.MAI->doesDwarfUseRelocationsAcrossSections())
369 U.addSectionLabel(D, A, L);
371 U.addSectionDelta(D, A, L, Sec);
374 void DwarfDebug::addScopeRangeList(DwarfCompileUnit &TheCU, DIE &ScopeDIE,
375 const SmallVectorImpl<InsnRange> &Range) {
376 // Emit offset in .debug_range as a relocatable label. emitDIE will handle
377 // emitting it appropriately.
378 MCSymbol *RangeSym = Asm->GetTempSymbol("debug_ranges", GlobalRangeCount++);
380 // Under fission, ranges are specified by constant offsets relative to the
381 // CU's DW_AT_GNU_ranges_base.
383 TheCU.addSectionDelta(ScopeDIE, dwarf::DW_AT_ranges, RangeSym,
384 DwarfDebugRangeSectionSym);
386 addSectionLabel(*Asm, TheCU, ScopeDIE, dwarf::DW_AT_ranges, RangeSym,
387 DwarfDebugRangeSectionSym);
389 RangeSpanList List(RangeSym);
390 for (const InsnRange &R : Range) {
391 RangeSpan Span(getLabelBeforeInsn(R.first), getLabelAfterInsn(R.second));
392 List.addRange(std::move(Span));
395 // Add the range list to the set of ranges to be emitted.
396 TheCU.addRangeList(std::move(List));
399 void DwarfDebug::attachRangesOrLowHighPC(DwarfCompileUnit &TheCU, DIE &Die,
400 const SmallVectorImpl<InsnRange> &Ranges) {
401 assert(!Ranges.empty());
402 if (Ranges.size() == 1)
403 attachLowHighPC(TheCU, Die, getLabelBeforeInsn(Ranges.front().first),
404 getLabelAfterInsn(Ranges.front().second));
406 addScopeRangeList(TheCU, Die, Ranges);
409 // Construct new DW_TAG_lexical_block for this scope and attach
410 // DW_AT_low_pc/DW_AT_high_pc labels.
412 DwarfDebug::constructLexicalScopeDIE(DwarfCompileUnit &TheCU,
413 LexicalScope *Scope) {
414 if (isLexicalScopeDIENull(Scope))
417 auto ScopeDIE = make_unique<DIE>(dwarf::DW_TAG_lexical_block);
418 if (Scope->isAbstractScope())
421 attachRangesOrLowHighPC(TheCU, *ScopeDIE, Scope->getRanges());
426 // This scope represents inlined body of a function. Construct DIE to
427 // represent this concrete inlined copy of the function.
429 DwarfDebug::constructInlinedScopeDIE(DwarfCompileUnit &TheCU,
430 LexicalScope *Scope) {
431 assert(Scope->getScopeNode());
432 DIScope DS(Scope->getScopeNode());
433 DISubprogram InlinedSP = getDISubprogram(DS);
434 // Find the subprogram's DwarfCompileUnit in the SPMap in case the subprogram
435 // was inlined from another compile unit.
436 DIE *OriginDIE = SPMap[InlinedSP]->getDIE(InlinedSP);
437 assert(OriginDIE && "Unable to find original DIE for an inlined subprogram.");
439 auto ScopeDIE = make_unique<DIE>(dwarf::DW_TAG_inlined_subroutine);
440 TheCU.addDIEEntry(*ScopeDIE, dwarf::DW_AT_abstract_origin, *OriginDIE);
442 attachRangesOrLowHighPC(TheCU, *ScopeDIE, Scope->getRanges());
444 InlinedSubprogramDIEs.insert(OriginDIE);
446 // Add the call site information to the DIE.
447 DILocation DL(Scope->getInlinedAt());
448 TheCU.addUInt(*ScopeDIE, dwarf::DW_AT_call_file, None,
449 TheCU.getOrCreateSourceID(DL.getFilename(), DL.getDirectory()));
450 TheCU.addUInt(*ScopeDIE, dwarf::DW_AT_call_line, None, DL.getLineNumber());
452 // Add name to the name table, we do this here because we're guaranteed
453 // to have concrete versions of our DW_TAG_inlined_subprogram nodes.
454 addSubprogramNames(InlinedSP, *ScopeDIE);
459 static std::unique_ptr<DIE> constructVariableDIE(DwarfCompileUnit &TheCU,
461 const LexicalScope &Scope,
462 DIE *&ObjectPointer) {
463 AbstractOrInlined AOI = AOI_None;
464 if (Scope.isAbstractScope())
466 else if (Scope.getInlinedAt())
468 auto Var = TheCU.constructVariableDIE(DV, AOI);
469 if (DV.isObjectPointer())
470 ObjectPointer = Var.get();
474 DIE *DwarfDebug::createScopeChildrenDIE(
475 DwarfCompileUnit &TheCU, LexicalScope *Scope,
476 SmallVectorImpl<std::unique_ptr<DIE>> &Children) {
477 DIE *ObjectPointer = nullptr;
479 // Collect arguments for current function.
480 if (LScopes.isCurrentFunctionScope(Scope)) {
481 for (DbgVariable *ArgDV : CurrentFnArguments)
484 constructVariableDIE(TheCU, *ArgDV, *Scope, ObjectPointer));
486 // If this is a variadic function, add an unspecified parameter.
487 DISubprogram SP(Scope->getScopeNode());
488 DIArray FnArgs = SP.getType().getTypeArray();
489 if (FnArgs.getElement(FnArgs.getNumElements() - 1)
490 .isUnspecifiedParameter()) {
492 make_unique<DIE>(dwarf::DW_TAG_unspecified_parameters));
496 // Collect lexical scope children first.
497 for (DbgVariable *DV : ScopeVariables.lookup(Scope))
498 Children.push_back(constructVariableDIE(TheCU, *DV, *Scope, ObjectPointer));
500 for (LexicalScope *LS : Scope->getChildren())
501 if (std::unique_ptr<DIE> Nested = constructScopeDIE(TheCU, LS))
502 Children.push_back(std::move(Nested));
503 return ObjectPointer;
506 void DwarfDebug::createAndAddScopeChildren(DwarfCompileUnit &TheCU,
507 LexicalScope *Scope, DIE &ScopeDIE) {
508 // We create children when the scope DIE is not null.
509 SmallVector<std::unique_ptr<DIE>, 8> Children;
510 if (DIE *ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children))
511 TheCU.addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, *ObjectPointer);
514 for (auto &I : Children)
515 ScopeDIE.addChild(std::move(I));
518 void DwarfDebug::constructAbstractSubprogramScopeDIE(DwarfCompileUnit &TheCU,
519 LexicalScope *Scope) {
520 assert(Scope && Scope->getScopeNode());
521 assert(Scope->isAbstractScope());
522 assert(!Scope->getInlinedAt());
524 DISubprogram Sub(Scope->getScopeNode());
526 if (!ProcessedSPNodes.insert(Sub))
529 // Find the subprogram's DwarfCompileUnit in the SPMap in case the subprogram
530 // was inlined from another compile unit.
531 DIE *ScopeDIE = SPMap[Sub]->getDIE(Sub);
533 AbstractSPDies.insert(std::make_pair(Sub, ScopeDIE));
534 TheCU.addUInt(*ScopeDIE, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined);
535 createAndAddScopeChildren(TheCU, Scope, *ScopeDIE);
538 DIE &DwarfDebug::constructSubprogramScopeDIE(DwarfCompileUnit &TheCU,
539 LexicalScope *Scope) {
540 assert(Scope && Scope->getScopeNode());
541 assert(!Scope->getInlinedAt());
542 assert(!Scope->isAbstractScope());
543 DISubprogram Sub(Scope->getScopeNode());
545 assert(Sub.isSubprogram());
547 ProcessedSPNodes.insert(Sub);
549 DIE &ScopeDIE = updateSubprogramScopeDIE(TheCU, Sub);
551 createAndAddScopeChildren(TheCU, Scope, ScopeDIE);
556 // Construct a DIE for this scope.
557 std::unique_ptr<DIE> DwarfDebug::constructScopeDIE(DwarfCompileUnit &TheCU,
558 LexicalScope *Scope) {
559 if (!Scope || !Scope->getScopeNode())
562 DIScope DS(Scope->getScopeNode());
564 assert((Scope->getInlinedAt() || !DS.isSubprogram()) &&
565 "Only handle inlined subprograms here, use "
566 "constructSubprogramScopeDIE for non-inlined "
569 SmallVector<std::unique_ptr<DIE>, 8> Children;
571 // We try to create the scope DIE first, then the children DIEs. This will
572 // avoid creating un-used children then removing them later when we find out
573 // the scope DIE is null.
574 std::unique_ptr<DIE> ScopeDIE;
575 if (Scope->getParent() && DS.isSubprogram()) {
576 ScopeDIE = constructInlinedScopeDIE(TheCU, Scope);
579 // We create children when the scope DIE is not null.
580 createScopeChildrenDIE(TheCU, Scope, Children);
582 // Early exit when we know the scope DIE is going to be null.
583 if (isLexicalScopeDIENull(Scope))
586 // We create children here when we know the scope DIE is not going to be
587 // null and the children will be added to the scope DIE.
588 createScopeChildrenDIE(TheCU, Scope, Children);
590 // There is no need to emit empty lexical block DIE.
591 std::pair<ImportedEntityMap::const_iterator,
592 ImportedEntityMap::const_iterator> Range =
593 std::equal_range(ScopesWithImportedEntities.begin(),
594 ScopesWithImportedEntities.end(),
595 std::pair<const MDNode *, const MDNode *>(DS, nullptr),
597 if (Children.empty() && Range.first == Range.second)
599 ScopeDIE = constructLexicalScopeDIE(TheCU, Scope);
600 assert(ScopeDIE && "Scope DIE should not be null.");
601 for (ImportedEntityMap::const_iterator i = Range.first; i != Range.second;
603 constructImportedEntityDIE(TheCU, i->second, *ScopeDIE);
607 for (auto &I : Children)
608 ScopeDIE->addChild(std::move(I));
613 void DwarfDebug::addGnuPubAttributes(DwarfUnit &U, DIE &D) const {
614 if (!GenerateGnuPubSections)
617 U.addFlag(D, dwarf::DW_AT_GNU_pubnames);
620 // Create new DwarfCompileUnit for the given metadata node with tag
621 // DW_TAG_compile_unit.
622 DwarfCompileUnit &DwarfDebug::constructDwarfCompileUnit(DICompileUnit DIUnit) {
623 StringRef FN = DIUnit.getFilename();
624 CompilationDir = DIUnit.getDirectory();
626 auto OwnedUnit = make_unique<DwarfCompileUnit>(
627 InfoHolder.getUnits().size(), DIUnit, Asm, this, &InfoHolder);
628 DwarfCompileUnit &NewCU = *OwnedUnit;
629 DIE &Die = NewCU.getUnitDie();
630 InfoHolder.addUnit(std::move(OwnedUnit));
632 // LTO with assembly output shares a single line table amongst multiple CUs.
633 // To avoid the compilation directory being ambiguous, let the line table
634 // explicitly describe the directory of all files, never relying on the
635 // compilation directory.
636 if (!Asm->OutStreamer.hasRawTextSupport() || SingleCU)
637 Asm->OutStreamer.getContext().setMCLineTableCompilationDir(
638 NewCU.getUniqueID(), CompilationDir);
640 NewCU.addString(Die, dwarf::DW_AT_producer, DIUnit.getProducer());
641 NewCU.addUInt(Die, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
642 DIUnit.getLanguage());
643 NewCU.addString(Die, dwarf::DW_AT_name, FN);
645 if (!useSplitDwarf()) {
646 NewCU.initStmtList(DwarfLineSectionSym);
648 // If we're using split dwarf the compilation dir is going to be in the
649 // skeleton CU and so we don't need to duplicate it here.
650 if (!CompilationDir.empty())
651 NewCU.addString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
653 addGnuPubAttributes(NewCU, Die);
656 if (DIUnit.isOptimized())
657 NewCU.addFlag(Die, dwarf::DW_AT_APPLE_optimized);
659 StringRef Flags = DIUnit.getFlags();
661 NewCU.addString(Die, dwarf::DW_AT_APPLE_flags, Flags);
663 if (unsigned RVer = DIUnit.getRunTimeVersion())
664 NewCU.addUInt(Die, dwarf::DW_AT_APPLE_major_runtime_vers,
665 dwarf::DW_FORM_data1, RVer);
670 if (useSplitDwarf()) {
671 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoDWOSection(),
672 DwarfInfoDWOSectionSym);
673 NewCU.setSkeleton(constructSkeletonCU(NewCU));
675 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
676 DwarfInfoSectionSym);
678 CUMap.insert(std::make_pair(DIUnit, &NewCU));
679 CUDieMap.insert(std::make_pair(&Die, &NewCU));
683 // Construct subprogram DIE.
684 void DwarfDebug::constructSubprogramDIE(DwarfCompileUnit &TheCU,
686 // FIXME: We should only call this routine once, however, during LTO if a
687 // program is defined in multiple CUs we could end up calling it out of
688 // beginModule as we walk the CUs.
690 DwarfCompileUnit *&CURef = SPMap[N];
696 assert(SP.isSubprogram());
697 assert(SP.isDefinition());
699 DIE &SubprogramDie = *TheCU.getOrCreateSubprogramDIE(SP);
701 // Expose as a global name.
702 TheCU.addGlobalName(SP.getName(), SubprogramDie, resolve(SP.getContext()));
705 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
707 DIImportedEntity Module(N);
708 assert(Module.Verify());
709 if (DIE *D = TheCU.getOrCreateContextDIE(Module.getContext()))
710 constructImportedEntityDIE(TheCU, Module, *D);
713 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
714 const MDNode *N, DIE &Context) {
715 DIImportedEntity Module(N);
716 assert(Module.Verify());
717 return constructImportedEntityDIE(TheCU, Module, Context);
720 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
721 const DIImportedEntity &Module,
723 assert(Module.Verify() &&
724 "Use one of the MDNode * overloads to handle invalid metadata");
725 DIE &IMDie = TheCU.createAndAddDIE(Module.getTag(), Context, Module);
727 DIDescriptor Entity = resolve(Module.getEntity());
728 if (Entity.isNameSpace())
729 EntityDie = TheCU.getOrCreateNameSpace(DINameSpace(Entity));
730 else if (Entity.isSubprogram())
731 EntityDie = TheCU.getOrCreateSubprogramDIE(DISubprogram(Entity));
732 else if (Entity.isType())
733 EntityDie = TheCU.getOrCreateTypeDIE(DIType(Entity));
735 EntityDie = TheCU.getDIE(Entity);
736 TheCU.addSourceLine(IMDie, Module.getLineNumber(),
737 Module.getContext().getFilename(),
738 Module.getContext().getDirectory());
739 TheCU.addDIEEntry(IMDie, dwarf::DW_AT_import, *EntityDie);
740 StringRef Name = Module.getName();
742 TheCU.addString(IMDie, dwarf::DW_AT_name, Name);
745 // Emit all Dwarf sections that should come prior to the content. Create
746 // global DIEs and emit initial debug info sections. This is invoked by
747 // the target AsmPrinter.
748 void DwarfDebug::beginModule() {
749 if (DisableDebugInfoPrinting)
752 const Module *M = MMI->getModule();
754 // If module has named metadata anchors then use them, otherwise scan the
755 // module using debug info finder to collect debug info.
756 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
759 TypeIdentifierMap = generateDITypeIdentifierMap(CU_Nodes);
761 // Emit initial sections so we can reference labels later.
764 SingleCU = CU_Nodes->getNumOperands() == 1;
766 for (MDNode *N : CU_Nodes->operands()) {
767 DICompileUnit CUNode(N);
768 DwarfCompileUnit &CU = constructDwarfCompileUnit(CUNode);
769 DIArray ImportedEntities = CUNode.getImportedEntities();
770 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
771 ScopesWithImportedEntities.push_back(std::make_pair(
772 DIImportedEntity(ImportedEntities.getElement(i)).getContext(),
773 ImportedEntities.getElement(i)));
774 std::sort(ScopesWithImportedEntities.begin(),
775 ScopesWithImportedEntities.end(), less_first());
776 DIArray GVs = CUNode.getGlobalVariables();
777 for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i)
778 CU.createGlobalVariableDIE(DIGlobalVariable(GVs.getElement(i)));
779 DIArray SPs = CUNode.getSubprograms();
780 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i)
781 constructSubprogramDIE(CU, SPs.getElement(i));
782 DIArray EnumTypes = CUNode.getEnumTypes();
783 for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i)
784 CU.getOrCreateTypeDIE(EnumTypes.getElement(i));
785 DIArray RetainedTypes = CUNode.getRetainedTypes();
786 for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i) {
787 DIType Ty(RetainedTypes.getElement(i));
788 // The retained types array by design contains pointers to
789 // MDNodes rather than DIRefs. Unique them here.
790 DIType UniqueTy(resolve(Ty.getRef()));
791 CU.getOrCreateTypeDIE(UniqueTy);
793 // Emit imported_modules last so that the relevant context is already
795 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
796 constructImportedEntityDIE(CU, ImportedEntities.getElement(i));
799 // Tell MMI that we have debug info.
800 MMI->setDebugInfoAvailability(true);
802 // Prime section data.
803 SectionMap[Asm->getObjFileLowering().getTextSection()];
806 // Collect info for variables that were optimized out.
807 void DwarfDebug::collectDeadVariables() {
808 const Module *M = MMI->getModule();
810 if (NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu")) {
811 for (MDNode *N : CU_Nodes->operands()) {
812 DICompileUnit TheCU(N);
813 // Construct subprogram DIE and add variables DIEs.
814 DwarfCompileUnit *SPCU =
815 static_cast<DwarfCompileUnit *>(CUMap.lookup(TheCU));
816 assert(SPCU && "Unable to find Compile Unit!");
817 DIArray Subprograms = TheCU.getSubprograms();
818 for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) {
819 DISubprogram SP(Subprograms.getElement(i));
820 if (ProcessedSPNodes.count(SP) != 0)
822 assert(SP.isSubprogram() &&
823 "CU's subprogram list contains a non-subprogram");
824 assert(SP.isDefinition() &&
825 "CU's subprogram list contains a subprogram declaration");
826 DIArray Variables = SP.getVariables();
827 if (Variables.getNumElements() == 0)
830 // FIXME: See the comment in constructSubprogramDIE about duplicate
832 constructSubprogramDIE(*SPCU, SP);
833 DIE *SPDIE = SPCU->getDIE(SP);
834 for (unsigned vi = 0, ve = Variables.getNumElements(); vi != ve; ++vi) {
835 DIVariable DV(Variables.getElement(vi));
836 assert(DV.isVariable());
837 DbgVariable NewVar(DV, nullptr, this);
838 SPDIE->addChild(SPCU->constructVariableDIE(NewVar));
845 void DwarfDebug::finalizeModuleInfo() {
846 // Collect info for variables that were optimized out.
847 collectDeadVariables();
849 // Handle anything that needs to be done on a per-unit basis after
850 // all other generation.
851 for (const auto &TheU : getUnits()) {
852 // Emit DW_AT_containing_type attribute to connect types with their
853 // vtable holding type.
854 TheU->constructContainingTypeDIEs();
856 // Add CU specific attributes if we need to add any.
857 if (TheU->getUnitDie().getTag() == dwarf::DW_TAG_compile_unit) {
858 // If we're splitting the dwarf out now that we've got the entire
859 // CU then add the dwo id to it.
860 DwarfCompileUnit *SkCU =
861 static_cast<DwarfCompileUnit *>(TheU->getSkeleton());
862 if (useSplitDwarf()) {
863 // Emit a unique identifier for this CU.
864 uint64_t ID = DIEHash(Asm).computeCUSignature(TheU->getUnitDie());
865 TheU->addUInt(TheU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
866 dwarf::DW_FORM_data8, ID);
867 SkCU->addUInt(SkCU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
868 dwarf::DW_FORM_data8, ID);
870 // We don't keep track of which addresses are used in which CU so this
871 // is a bit pessimistic under LTO.
872 if (!AddrPool.isEmpty())
873 addSectionLabel(*Asm, *SkCU, SkCU->getUnitDie(),
874 dwarf::DW_AT_GNU_addr_base, DwarfAddrSectionSym,
875 DwarfAddrSectionSym);
876 if (!TheU->getRangeLists().empty())
877 addSectionLabel(*Asm, *SkCU, SkCU->getUnitDie(),
878 dwarf::DW_AT_GNU_ranges_base,
879 DwarfDebugRangeSectionSym, DwarfDebugRangeSectionSym);
882 // If we have code split among multiple sections or non-contiguous
883 // ranges of code then emit a DW_AT_ranges attribute on the unit that will
884 // remain in the .o file, otherwise add a DW_AT_low_pc.
885 // FIXME: We should use ranges allow reordering of code ala
886 // .subsections_via_symbols in mach-o. This would mean turning on
887 // ranges for all subprogram DIEs for mach-o.
888 DwarfCompileUnit &U =
889 SkCU ? *SkCU : static_cast<DwarfCompileUnit &>(*TheU);
890 unsigned NumRanges = TheU->getRanges().size();
893 addSectionLabel(*Asm, U, U.getUnitDie(), dwarf::DW_AT_ranges,
894 Asm->GetTempSymbol("cu_ranges", U.getUniqueID()),
895 DwarfDebugRangeSectionSym);
897 // A DW_AT_low_pc attribute may also be specified in combination with
898 // DW_AT_ranges to specify the default base address for use in
899 // location lists (see Section 2.6.2) and range lists (see Section
901 U.addUInt(U.getUnitDie(), dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr,
904 RangeSpan &Range = TheU->getRanges().back();
905 U.addLocalLabelAddress(U.getUnitDie(), dwarf::DW_AT_low_pc,
907 U.addLabelDelta(U.getUnitDie(), dwarf::DW_AT_high_pc, Range.getEnd(),
914 // Compute DIE offsets and sizes.
915 InfoHolder.computeSizeAndOffsets();
917 SkeletonHolder.computeSizeAndOffsets();
920 void DwarfDebug::endSections() {
921 // Filter labels by section.
922 for (const SymbolCU &SCU : ArangeLabels) {
923 if (SCU.Sym->isInSection()) {
924 // Make a note of this symbol and it's section.
925 const MCSection *Section = &SCU.Sym->getSection();
926 if (!Section->getKind().isMetadata())
927 SectionMap[Section].push_back(SCU);
929 // Some symbols (e.g. common/bss on mach-o) can have no section but still
930 // appear in the output. This sucks as we rely on sections to build
931 // arange spans. We can do it without, but it's icky.
932 SectionMap[nullptr].push_back(SCU);
936 // Build a list of sections used.
937 std::vector<const MCSection *> Sections;
938 for (const auto &it : SectionMap) {
939 const MCSection *Section = it.first;
940 Sections.push_back(Section);
943 // Sort the sections into order.
944 // This is only done to ensure consistent output order across different runs.
945 std::sort(Sections.begin(), Sections.end(), SectionSort);
947 // Add terminating symbols for each section.
948 for (unsigned ID = 0, E = Sections.size(); ID != E; ID++) {
949 const MCSection *Section = Sections[ID];
950 MCSymbol *Sym = nullptr;
953 // We can't call MCSection::getLabelEndName, as it's only safe to do so
954 // if we know the section name up-front. For user-created sections, the
955 // resulting label may not be valid to use as a label. (section names can
956 // use a greater set of characters on some systems)
957 Sym = Asm->GetTempSymbol("debug_end", ID);
958 Asm->OutStreamer.SwitchSection(Section);
959 Asm->OutStreamer.EmitLabel(Sym);
962 // Insert a final terminator.
963 SectionMap[Section].push_back(SymbolCU(nullptr, Sym));
967 // Emit all Dwarf sections that should come after the content.
968 void DwarfDebug::endModule() {
969 assert(CurFn == nullptr);
970 assert(CurMI == nullptr);
975 // End any existing sections.
976 // TODO: Does this need to happen?
979 // Finalize the debug info for the module.
980 finalizeModuleInfo();
984 // Emit all the DIEs into a debug info section.
987 // Corresponding abbreviations into a abbrev section.
990 // Emit info into a debug aranges section.
991 if (GenerateARangeSection)
994 // Emit info into a debug ranges section.
997 if (useSplitDwarf()) {
1000 emitDebugAbbrevDWO();
1002 // Emit DWO addresses.
1003 AddrPool.emit(*Asm, Asm->getObjFileLowering().getDwarfAddrSection());
1006 // Emit info into a debug loc section.
1009 // Emit info into the dwarf accelerator table sections.
1010 if (useDwarfAccelTables()) {
1013 emitAccelNamespaces();
1017 // Emit the pubnames and pubtypes sections if requested.
1018 if (HasDwarfPubSections) {
1019 emitDebugPubNames(GenerateGnuPubSections);
1020 emitDebugPubTypes(GenerateGnuPubSections);
1025 AbstractVariables.clear();
1027 // Reset these for the next Module if we have one.
1031 // Find abstract variable, if any, associated with Var.
1032 DbgVariable *DwarfDebug::findAbstractVariable(DIVariable &DV,
1033 DebugLoc ScopeLoc) {
1034 return findAbstractVariable(DV, ScopeLoc.getScope(DV->getContext()));
1037 DbgVariable *DwarfDebug::findAbstractVariable(DIVariable &DV,
1038 const MDNode *ScopeNode) {
1039 LLVMContext &Ctx = DV->getContext();
1040 // More then one inlined variable corresponds to one abstract variable.
1041 DIVariable Var = cleanseInlinedVariable(DV, Ctx);
1042 auto I = AbstractVariables.find(Var);
1043 if (I != AbstractVariables.end())
1044 return I->second.get();
1046 LexicalScope *Scope = LScopes.findAbstractScope(ScopeNode);
1050 auto AbsDbgVariable = make_unique<DbgVariable>(Var, nullptr, this);
1051 addScopeVariable(Scope, AbsDbgVariable.get());
1052 return (AbstractVariables[Var] = std::move(AbsDbgVariable)).get();
1055 // If Var is a current function argument then add it to CurrentFnArguments list.
1056 bool DwarfDebug::addCurrentFnArgument(DbgVariable *Var, LexicalScope *Scope) {
1057 if (!LScopes.isCurrentFunctionScope(Scope))
1059 DIVariable DV = Var->getVariable();
1060 if (DV.getTag() != dwarf::DW_TAG_arg_variable)
1062 unsigned ArgNo = DV.getArgNumber();
1066 size_t Size = CurrentFnArguments.size();
1068 CurrentFnArguments.resize(CurFn->getFunction()->arg_size());
1069 // llvm::Function argument size is not good indicator of how many
1070 // arguments does the function have at source level.
1072 CurrentFnArguments.resize(ArgNo * 2);
1073 CurrentFnArguments[ArgNo - 1] = Var;
1077 // Collect variable information from side table maintained by MMI.
1078 void DwarfDebug::collectVariableInfoFromMMITable(
1079 SmallPtrSet<const MDNode *, 16> &Processed) {
1080 for (const auto &VI : MMI->getVariableDbgInfo()) {
1083 Processed.insert(VI.Var);
1084 DIVariable DV(VI.Var);
1085 LexicalScope *Scope = LScopes.findLexicalScope(VI.Loc);
1087 // If variable scope is not found then skip this variable.
1091 DbgVariable *AbsDbgVariable = findAbstractVariable(DV, VI.Loc);
1092 DbgVariable *RegVar = new DbgVariable(DV, AbsDbgVariable, this);
1093 RegVar->setFrameIndex(VI.Slot);
1094 if (!addCurrentFnArgument(RegVar, Scope))
1095 addScopeVariable(Scope, RegVar);
1099 // Get .debug_loc entry for the instruction range starting at MI.
1100 static DebugLocEntry::Value getDebugLocValue(const MachineInstr *MI) {
1101 const MDNode *Var = MI->getDebugVariable();
1103 assert(MI->getNumOperands() == 3);
1104 if (MI->getOperand(0).isReg()) {
1105 MachineLocation MLoc;
1106 // If the second operand is an immediate, this is a
1107 // register-indirect address.
1108 if (!MI->getOperand(1).isImm())
1109 MLoc.set(MI->getOperand(0).getReg());
1111 MLoc.set(MI->getOperand(0).getReg(), MI->getOperand(1).getImm());
1112 return DebugLocEntry::Value(Var, MLoc);
1114 if (MI->getOperand(0).isImm())
1115 return DebugLocEntry::Value(Var, MI->getOperand(0).getImm());
1116 if (MI->getOperand(0).isFPImm())
1117 return DebugLocEntry::Value(Var, MI->getOperand(0).getFPImm());
1118 if (MI->getOperand(0).isCImm())
1119 return DebugLocEntry::Value(Var, MI->getOperand(0).getCImm());
1121 llvm_unreachable("Unexpected 3 operand DBG_VALUE instruction!");
1124 // Find variables for each lexical scope.
1126 DwarfDebug::collectVariableInfo(SmallPtrSet<const MDNode *, 16> &Processed) {
1127 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1128 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1130 // Grab the variable info that was squirreled away in the MMI side-table.
1131 collectVariableInfoFromMMITable(Processed);
1133 for (const auto &I : DbgValues) {
1134 DIVariable DV(I.first);
1135 if (Processed.count(DV))
1138 // History contains relevant DBG_VALUE instructions for DV and instructions
1140 const SmallVectorImpl<const MachineInstr *> &History = I.second;
1141 if (History.empty())
1143 const MachineInstr *MInsn = History.front();
1145 LexicalScope *Scope = nullptr;
1146 if (DV.getTag() == dwarf::DW_TAG_arg_variable &&
1147 DISubprogram(DV.getContext()).describes(CurFn->getFunction()))
1148 Scope = LScopes.getCurrentFunctionScope();
1149 else if (MDNode *IA = DV.getInlinedAt()) {
1150 DebugLoc DL = DebugLoc::getFromDILocation(IA);
1151 Scope = LScopes.findInlinedScope(DebugLoc::get(
1152 DL.getLine(), DL.getCol(), DV.getContext(), IA));
1154 Scope = LScopes.findLexicalScope(DV.getContext());
1155 // If variable scope is not found then skip this variable.
1159 Processed.insert(DV);
1160 assert(MInsn->isDebugValue() && "History must begin with debug value");
1161 DbgVariable *AbsVar = findAbstractVariable(DV, MInsn->getDebugLoc());
1162 DbgVariable *RegVar = new DbgVariable(DV, AbsVar, this);
1163 if (!addCurrentFnArgument(RegVar, Scope))
1164 addScopeVariable(Scope, RegVar);
1166 AbsVar->setMInsn(MInsn);
1168 // Simplify ranges that are fully coalesced.
1169 if (History.size() <= 1 ||
1170 (History.size() == 2 && MInsn->isIdenticalTo(History.back()))) {
1171 RegVar->setMInsn(MInsn);
1175 // Handle multiple DBG_VALUE instructions describing one variable.
1176 RegVar->setDotDebugLocOffset(DotDebugLocEntries.size());
1178 DotDebugLocEntries.resize(DotDebugLocEntries.size() + 1);
1179 DebugLocList &LocList = DotDebugLocEntries.back();
1181 Asm->GetTempSymbol("debug_loc", DotDebugLocEntries.size() - 1);
1182 SmallVector<DebugLocEntry, 4> &DebugLoc = LocList.List;
1183 for (SmallVectorImpl<const MachineInstr *>::const_iterator
1184 HI = History.begin(),
1187 const MachineInstr *Begin = *HI;
1188 assert(Begin->isDebugValue() && "Invalid History entry");
1190 // Check if DBG_VALUE is truncating a range.
1191 if (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() &&
1192 !Begin->getOperand(0).getReg())
1195 // Compute the range for a register location.
1196 const MCSymbol *FLabel = getLabelBeforeInsn(Begin);
1197 const MCSymbol *SLabel = nullptr;
1200 // If Begin is the last instruction in History then its value is valid
1201 // until the end of the function.
1202 SLabel = FunctionEndSym;
1204 const MachineInstr *End = HI[1];
1205 DEBUG(dbgs() << "DotDebugLoc Pair:\n"
1206 << "\t" << *Begin << "\t" << *End << "\n");
1207 if (End->isDebugValue() && End->getDebugVariable() == DV)
1208 SLabel = getLabelBeforeInsn(End);
1210 // End is clobbering the range.
1211 SLabel = getLabelAfterInsn(End);
1212 assert(SLabel && "Forgot label after clobber instruction");
1217 // The value is valid until the next DBG_VALUE or clobber.
1218 DebugLocEntry Loc(FLabel, SLabel, getDebugLocValue(Begin), TheCU);
1219 if (DebugLoc.empty() || !DebugLoc.back().Merge(Loc))
1220 DebugLoc.push_back(std::move(Loc));
1224 // Collect info for variables that were optimized out.
1225 DIArray Variables = DISubprogram(FnScope->getScopeNode()).getVariables();
1226 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1227 DIVariable DV(Variables.getElement(i));
1228 assert(DV.isVariable());
1229 if (!Processed.insert(DV))
1231 if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext()))
1234 new DbgVariable(DV, findAbstractVariable(DV, Scope->getScopeNode()),
1239 // Return Label preceding the instruction.
1240 MCSymbol *DwarfDebug::getLabelBeforeInsn(const MachineInstr *MI) {
1241 MCSymbol *Label = LabelsBeforeInsn.lookup(MI);
1242 assert(Label && "Didn't insert label before instruction");
1246 // Return Label immediately following the instruction.
1247 MCSymbol *DwarfDebug::getLabelAfterInsn(const MachineInstr *MI) {
1248 return LabelsAfterInsn.lookup(MI);
1251 // Process beginning of an instruction.
1252 void DwarfDebug::beginInstruction(const MachineInstr *MI) {
1253 assert(CurMI == nullptr);
1255 // Check if source location changes, but ignore DBG_VALUE locations.
1256 if (!MI->isDebugValue()) {
1257 DebugLoc DL = MI->getDebugLoc();
1258 if (DL != PrevInstLoc && (!DL.isUnknown() || UnknownLocations)) {
1261 if (DL == PrologEndLoc) {
1262 Flags |= DWARF2_FLAG_PROLOGUE_END;
1263 PrologEndLoc = DebugLoc();
1265 if (PrologEndLoc.isUnknown())
1266 Flags |= DWARF2_FLAG_IS_STMT;
1268 if (!DL.isUnknown()) {
1269 const MDNode *Scope = DL.getScope(Asm->MF->getFunction()->getContext());
1270 recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags);
1272 recordSourceLine(0, 0, nullptr, 0);
1276 // Insert labels where requested.
1277 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1278 LabelsBeforeInsn.find(MI);
1281 if (I == LabelsBeforeInsn.end())
1284 // Label already assigned.
1289 PrevLabel = MMI->getContext().CreateTempSymbol();
1290 Asm->OutStreamer.EmitLabel(PrevLabel);
1292 I->second = PrevLabel;
1295 // Process end of an instruction.
1296 void DwarfDebug::endInstruction() {
1297 assert(CurMI != nullptr);
1298 // Don't create a new label after DBG_VALUE instructions.
1299 // They don't generate code.
1300 if (!CurMI->isDebugValue())
1301 PrevLabel = nullptr;
1303 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1304 LabelsAfterInsn.find(CurMI);
1308 if (I == LabelsAfterInsn.end())
1311 // Label already assigned.
1315 // We need a label after this instruction.
1317 PrevLabel = MMI->getContext().CreateTempSymbol();
1318 Asm->OutStreamer.EmitLabel(PrevLabel);
1320 I->second = PrevLabel;
1323 // Each LexicalScope has first instruction and last instruction to mark
1324 // beginning and end of a scope respectively. Create an inverse map that list
1325 // scopes starts (and ends) with an instruction. One instruction may start (or
1326 // end) multiple scopes. Ignore scopes that are not reachable.
1327 void DwarfDebug::identifyScopeMarkers() {
1328 SmallVector<LexicalScope *, 4> WorkList;
1329 WorkList.push_back(LScopes.getCurrentFunctionScope());
1330 while (!WorkList.empty()) {
1331 LexicalScope *S = WorkList.pop_back_val();
1333 const SmallVectorImpl<LexicalScope *> &Children = S->getChildren();
1334 if (!Children.empty())
1335 WorkList.append(Children.begin(), Children.end());
1337 if (S->isAbstractScope())
1340 for (const InsnRange &R : S->getRanges()) {
1341 assert(R.first && "InsnRange does not have first instruction!");
1342 assert(R.second && "InsnRange does not have second instruction!");
1343 requestLabelBeforeInsn(R.first);
1344 requestLabelAfterInsn(R.second);
1349 // Gather pre-function debug information. Assumes being called immediately
1350 // after the function entry point has been emitted.
1351 void DwarfDebug::beginFunction(const MachineFunction *MF) {
1354 // If there's no debug info for the function we're not going to do anything.
1355 if (!MMI->hasDebugInfo())
1358 // Grab the lexical scopes for the function, if we don't have any of those
1359 // then we're not going to be able to do anything.
1360 LScopes.initialize(*MF);
1361 if (LScopes.empty())
1364 assert(DbgValues.empty() && "DbgValues map wasn't cleaned!");
1366 // Make sure that each lexical scope will have a begin/end label.
1367 identifyScopeMarkers();
1369 // Set DwarfDwarfCompileUnitID in MCContext to the Compile Unit this function
1370 // belongs to so that we add to the correct per-cu line table in the
1372 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1373 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1374 assert(TheCU && "Unable to find compile unit!");
1375 if (Asm->OutStreamer.hasRawTextSupport())
1376 // Use a single line table if we are generating assembly.
1377 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1379 Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID());
1381 // Emit a label for the function so that we have a beginning address.
1382 FunctionBeginSym = Asm->GetTempSymbol("func_begin", Asm->getFunctionNumber());
1383 // Assumes in correct section after the entry point.
1384 Asm->OutStreamer.EmitLabel(FunctionBeginSym);
1386 // Collect user variables, find the end of the prologue.
1387 for (const auto &MBB : *MF) {
1388 for (const auto &MI : MBB) {
1389 if (MI.isDebugValue()) {
1390 assert(MI.getNumOperands() > 1 && "Invalid machine instruction!");
1391 // Keep track of user variables in order of appearance. Create the
1392 // empty history for each variable so that the order of keys in
1393 // DbgValues is correct. Actual history will be populated in
1394 // calculateDbgValueHistory() function.
1395 const MDNode *Var = MI.getDebugVariable();
1397 std::make_pair(Var, SmallVector<const MachineInstr *, 4>()));
1398 } else if (!MI.getFlag(MachineInstr::FrameSetup) &&
1399 PrologEndLoc.isUnknown() && !MI.getDebugLoc().isUnknown()) {
1400 // First known non-DBG_VALUE and non-frame setup location marks
1401 // the beginning of the function body.
1402 PrologEndLoc = MI.getDebugLoc();
1407 // Calculate history for local variables.
1408 calculateDbgValueHistory(MF, Asm->TM.getRegisterInfo(), DbgValues);
1410 // Request labels for the full history.
1411 for (auto &I : DbgValues) {
1412 const SmallVectorImpl<const MachineInstr *> &History = I.second;
1413 if (History.empty())
1416 // The first mention of a function argument gets the FunctionBeginSym
1417 // label, so arguments are visible when breaking at function entry.
1418 DIVariable DV(I.first);
1419 if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable &&
1420 getDISubprogram(DV.getContext()).describes(MF->getFunction()))
1421 LabelsBeforeInsn[History.front()] = FunctionBeginSym;
1423 for (const MachineInstr *MI : History) {
1424 if (MI->isDebugValue() && MI->getDebugVariable() == DV)
1425 requestLabelBeforeInsn(MI);
1427 requestLabelAfterInsn(MI);
1431 PrevInstLoc = DebugLoc();
1432 PrevLabel = FunctionBeginSym;
1434 // Record beginning of function.
1435 if (!PrologEndLoc.isUnknown()) {
1436 DebugLoc FnStartDL =
1437 PrologEndLoc.getFnDebugLoc(MF->getFunction()->getContext());
1439 FnStartDL.getLine(), FnStartDL.getCol(),
1440 FnStartDL.getScope(MF->getFunction()->getContext()),
1441 // We'd like to list the prologue as "not statements" but GDB behaves
1442 // poorly if we do that. Revisit this with caution/GDB (7.5+) testing.
1443 DWARF2_FLAG_IS_STMT);
1447 void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) {
1448 SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS];
1449 DIVariable DV = Var->getVariable();
1450 // Variables with positive arg numbers are parameters.
1451 if (unsigned ArgNum = DV.getArgNumber()) {
1452 // Keep all parameters in order at the start of the variable list to ensure
1453 // function types are correct (no out-of-order parameters)
1455 // This could be improved by only doing it for optimized builds (unoptimized
1456 // builds have the right order to begin with), searching from the back (this
1457 // would catch the unoptimized case quickly), or doing a binary search
1458 // rather than linear search.
1459 SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin();
1460 while (I != Vars.end()) {
1461 unsigned CurNum = (*I)->getVariable().getArgNumber();
1462 // A local (non-parameter) variable has been found, insert immediately
1466 // A later indexed parameter has been found, insert immediately before it.
1467 if (CurNum > ArgNum)
1471 Vars.insert(I, Var);
1475 Vars.push_back(Var);
1478 // Gather and emit post-function debug information.
1479 void DwarfDebug::endFunction(const MachineFunction *MF) {
1480 // Every beginFunction(MF) call should be followed by an endFunction(MF) call,
1481 // though the beginFunction may not be called at all.
1482 // We should handle both cases.
1486 assert(CurFn == MF);
1487 assert(CurFn != nullptr);
1489 if (!MMI->hasDebugInfo() || LScopes.empty()) {
1490 // If we don't have a lexical scope for this function then there will
1491 // be a hole in the range information. Keep note of this by setting the
1492 // previously used section to nullptr.
1493 PrevSection = nullptr;
1499 // Define end label for subprogram.
1500 FunctionEndSym = Asm->GetTempSymbol("func_end", Asm->getFunctionNumber());
1501 // Assumes in correct section after the entry point.
1502 Asm->OutStreamer.EmitLabel(FunctionEndSym);
1504 // Set DwarfDwarfCompileUnitID in MCContext to default value.
1505 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1507 SmallPtrSet<const MDNode *, 16> ProcessedVars;
1508 collectVariableInfo(ProcessedVars);
1510 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1511 DwarfCompileUnit &TheCU = *SPMap.lookup(FnScope->getScopeNode());
1513 // Construct abstract scopes.
1514 for (LexicalScope *AScope : LScopes.getAbstractScopesList()) {
1515 DISubprogram SP(AScope->getScopeNode());
1516 if (!SP.isSubprogram())
1518 // Collect info for variables that were optimized out.
1519 DIArray Variables = SP.getVariables();
1520 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1521 DIVariable DV(Variables.getElement(i));
1522 assert(DV && DV.isVariable());
1523 if (!ProcessedVars.insert(DV))
1525 findAbstractVariable(DV, DV.getContext());
1527 constructAbstractSubprogramScopeDIE(TheCU, AScope);
1530 DIE &CurFnDIE = constructSubprogramScopeDIE(TheCU, FnScope);
1531 if (!CurFn->getTarget().Options.DisableFramePointerElim(*CurFn))
1532 TheCU.addFlag(CurFnDIE, dwarf::DW_AT_APPLE_omit_frame_ptr);
1534 // Add the range of this function to the list of ranges for the CU.
1535 RangeSpan Span(FunctionBeginSym, FunctionEndSym);
1536 TheCU.addRange(std::move(Span));
1537 PrevSection = Asm->getCurrentSection();
1541 // Ownership of DbgVariables is a bit subtle - ScopeVariables owns all the
1542 // DbgVariables except those that are also in AbstractVariables (since they
1543 // can be used cross-function)
1544 for (const auto &I : ScopeVariables)
1545 for (const auto *Var : I.second)
1546 if (!AbstractVariables.count(Var->getVariable()) || Var->getAbstractVariable())
1548 ScopeVariables.clear();
1549 DeleteContainerPointers(CurrentFnArguments);
1551 LabelsBeforeInsn.clear();
1552 LabelsAfterInsn.clear();
1553 PrevLabel = nullptr;
1557 // Register a source line with debug info. Returns the unique label that was
1558 // emitted and which provides correspondence to the source line list.
1559 void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S,
1564 unsigned Discriminator = 0;
1565 if (DIScope Scope = DIScope(S)) {
1566 assert(Scope.isScope());
1567 Fn = Scope.getFilename();
1568 Dir = Scope.getDirectory();
1569 if (Scope.isLexicalBlock())
1570 Discriminator = DILexicalBlock(S).getDiscriminator();
1572 unsigned CUID = Asm->OutStreamer.getContext().getDwarfCompileUnitID();
1573 Src = static_cast<DwarfCompileUnit &>(*InfoHolder.getUnits()[CUID])
1574 .getOrCreateSourceID(Fn, Dir);
1576 Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0,
1580 //===----------------------------------------------------------------------===//
1582 //===----------------------------------------------------------------------===//
1584 // Emit initial Dwarf sections with a label at the start of each one.
1585 void DwarfDebug::emitSectionLabels() {
1586 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
1588 // Dwarf sections base addresses.
1589 DwarfInfoSectionSym =
1590 emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info");
1591 if (useSplitDwarf()) {
1592 DwarfInfoDWOSectionSym =
1593 emitSectionSym(Asm, TLOF.getDwarfInfoDWOSection(), "section_info_dwo");
1594 DwarfTypesDWOSectionSym =
1595 emitSectionSym(Asm, TLOF.getDwarfTypesDWOSection(), "section_types_dwo");
1597 DwarfAbbrevSectionSym =
1598 emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev");
1599 if (useSplitDwarf())
1600 DwarfAbbrevDWOSectionSym = emitSectionSym(
1601 Asm, TLOF.getDwarfAbbrevDWOSection(), "section_abbrev_dwo");
1602 if (GenerateARangeSection)
1603 emitSectionSym(Asm, TLOF.getDwarfARangesSection());
1605 DwarfLineSectionSym =
1606 emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line");
1607 if (GenerateGnuPubSections) {
1608 DwarfGnuPubNamesSectionSym =
1609 emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection());
1610 DwarfGnuPubTypesSectionSym =
1611 emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection());
1612 } else if (HasDwarfPubSections) {
1613 emitSectionSym(Asm, TLOF.getDwarfPubNamesSection());
1614 emitSectionSym(Asm, TLOF.getDwarfPubTypesSection());
1617 DwarfStrSectionSym =
1618 emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string");
1619 if (useSplitDwarf()) {
1620 DwarfStrDWOSectionSym =
1621 emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string");
1622 DwarfAddrSectionSym =
1623 emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec");
1624 DwarfDebugLocSectionSym =
1625 emitSectionSym(Asm, TLOF.getDwarfLocDWOSection(), "skel_loc");
1627 DwarfDebugLocSectionSym =
1628 emitSectionSym(Asm, TLOF.getDwarfLocSection(), "section_debug_loc");
1629 DwarfDebugRangeSectionSym =
1630 emitSectionSym(Asm, TLOF.getDwarfRangesSection(), "debug_range");
1633 // Recursively emits a debug information entry.
1634 void DwarfDebug::emitDIE(DIE &Die) {
1635 // Get the abbreviation for this DIE.
1636 const DIEAbbrev &Abbrev = Die.getAbbrev();
1638 // Emit the code (index) for the abbreviation.
1639 if (Asm->isVerbose())
1640 Asm->OutStreamer.AddComment("Abbrev [" + Twine(Abbrev.getNumber()) +
1641 "] 0x" + Twine::utohexstr(Die.getOffset()) +
1642 ":0x" + Twine::utohexstr(Die.getSize()) + " " +
1643 dwarf::TagString(Abbrev.getTag()));
1644 Asm->EmitULEB128(Abbrev.getNumber());
1646 const SmallVectorImpl<DIEValue *> &Values = Die.getValues();
1647 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
1649 // Emit the DIE attribute values.
1650 for (unsigned i = 0, N = Values.size(); i < N; ++i) {
1651 dwarf::Attribute Attr = AbbrevData[i].getAttribute();
1652 dwarf::Form Form = AbbrevData[i].getForm();
1653 assert(Form && "Too many attributes for DIE (check abbreviation)");
1655 if (Asm->isVerbose()) {
1656 Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr));
1657 if (Attr == dwarf::DW_AT_accessibility)
1658 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(
1659 cast<DIEInteger>(Values[i])->getValue()));
1662 // Emit an attribute using the defined form.
1663 Values[i]->EmitValue(Asm, Form);
1666 // Emit the DIE children if any.
1667 if (Abbrev.hasChildren()) {
1668 for (auto &Child : Die.getChildren())
1671 Asm->OutStreamer.AddComment("End Of Children Mark");
1676 // Emit the debug info section.
1677 void DwarfDebug::emitDebugInfo() {
1678 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1680 Holder.emitUnits(this, DwarfAbbrevSectionSym);
1683 // Emit the abbreviation section.
1684 void DwarfDebug::emitAbbreviations() {
1685 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1687 Holder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection());
1690 // Emit the last address of the section and the end of the line matrix.
1691 void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) {
1692 // Define last address of section.
1693 Asm->OutStreamer.AddComment("Extended Op");
1696 Asm->OutStreamer.AddComment("Op size");
1697 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1);
1698 Asm->OutStreamer.AddComment("DW_LNE_set_address");
1699 Asm->EmitInt8(dwarf::DW_LNE_set_address);
1701 Asm->OutStreamer.AddComment("Section end label");
1703 Asm->OutStreamer.EmitSymbolValue(
1704 Asm->GetTempSymbol("section_end", SectionEnd),
1705 Asm->getDataLayout().getPointerSize());
1707 // Mark end of matrix.
1708 Asm->OutStreamer.AddComment("DW_LNE_end_sequence");
1714 // Emit visible names into a hashed accelerator table section.
1715 void DwarfDebug::emitAccelNames() {
1716 AccelNames.FinalizeTable(Asm, "Names");
1717 Asm->OutStreamer.SwitchSection(
1718 Asm->getObjFileLowering().getDwarfAccelNamesSection());
1719 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin");
1720 Asm->OutStreamer.EmitLabel(SectionBegin);
1722 // Emit the full data.
1723 AccelNames.Emit(Asm, SectionBegin, &InfoHolder);
1726 // Emit objective C classes and categories into a hashed accelerator table
1728 void DwarfDebug::emitAccelObjC() {
1729 AccelObjC.FinalizeTable(Asm, "ObjC");
1730 Asm->OutStreamer.SwitchSection(
1731 Asm->getObjFileLowering().getDwarfAccelObjCSection());
1732 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin");
1733 Asm->OutStreamer.EmitLabel(SectionBegin);
1735 // Emit the full data.
1736 AccelObjC.Emit(Asm, SectionBegin, &InfoHolder);
1739 // Emit namespace dies into a hashed accelerator table.
1740 void DwarfDebug::emitAccelNamespaces() {
1741 AccelNamespace.FinalizeTable(Asm, "namespac");
1742 Asm->OutStreamer.SwitchSection(
1743 Asm->getObjFileLowering().getDwarfAccelNamespaceSection());
1744 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin");
1745 Asm->OutStreamer.EmitLabel(SectionBegin);
1747 // Emit the full data.
1748 AccelNamespace.Emit(Asm, SectionBegin, &InfoHolder);
1751 // Emit type dies into a hashed accelerator table.
1752 void DwarfDebug::emitAccelTypes() {
1754 AccelTypes.FinalizeTable(Asm, "types");
1755 Asm->OutStreamer.SwitchSection(
1756 Asm->getObjFileLowering().getDwarfAccelTypesSection());
1757 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin");
1758 Asm->OutStreamer.EmitLabel(SectionBegin);
1760 // Emit the full data.
1761 AccelTypes.Emit(Asm, SectionBegin, &InfoHolder);
1764 // Public name handling.
1765 // The format for the various pubnames:
1767 // dwarf pubnames - offset/name pairs where the offset is the offset into the CU
1768 // for the DIE that is named.
1770 // gnu pubnames - offset/index value/name tuples where the offset is the offset
1771 // into the CU and the index value is computed according to the type of value
1772 // for the DIE that is named.
1774 // For type units the offset is the offset of the skeleton DIE. For split dwarf
1775 // it's the offset within the debug_info/debug_types dwo section, however, the
1776 // reference in the pubname header doesn't change.
1778 /// computeIndexValue - Compute the gdb index value for the DIE and CU.
1779 static dwarf::PubIndexEntryDescriptor computeIndexValue(DwarfUnit *CU,
1781 dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC;
1783 // We could have a specification DIE that has our most of our knowledge,
1784 // look for that now.
1785 DIEValue *SpecVal = Die->findAttribute(dwarf::DW_AT_specification);
1787 DIE &SpecDIE = cast<DIEEntry>(SpecVal)->getEntry();
1788 if (SpecDIE.findAttribute(dwarf::DW_AT_external))
1789 Linkage = dwarf::GIEL_EXTERNAL;
1790 } else if (Die->findAttribute(dwarf::DW_AT_external))
1791 Linkage = dwarf::GIEL_EXTERNAL;
1793 switch (Die->getTag()) {
1794 case dwarf::DW_TAG_class_type:
1795 case dwarf::DW_TAG_structure_type:
1796 case dwarf::DW_TAG_union_type:
1797 case dwarf::DW_TAG_enumeration_type:
1798 return dwarf::PubIndexEntryDescriptor(
1799 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus
1800 ? dwarf::GIEL_STATIC
1801 : dwarf::GIEL_EXTERNAL);
1802 case dwarf::DW_TAG_typedef:
1803 case dwarf::DW_TAG_base_type:
1804 case dwarf::DW_TAG_subrange_type:
1805 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC);
1806 case dwarf::DW_TAG_namespace:
1807 return dwarf::GIEK_TYPE;
1808 case dwarf::DW_TAG_subprogram:
1809 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage);
1810 case dwarf::DW_TAG_constant:
1811 case dwarf::DW_TAG_variable:
1812 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage);
1813 case dwarf::DW_TAG_enumerator:
1814 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE,
1815 dwarf::GIEL_STATIC);
1817 return dwarf::GIEK_NONE;
1821 /// emitDebugPubNames - Emit visible names into a debug pubnames section.
1823 void DwarfDebug::emitDebugPubNames(bool GnuStyle) {
1824 const MCSection *PSec =
1825 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection()
1826 : Asm->getObjFileLowering().getDwarfPubNamesSection();
1828 emitDebugPubSection(GnuStyle, PSec, "Names", &DwarfUnit::getGlobalNames);
1831 void DwarfDebug::emitDebugPubSection(
1832 bool GnuStyle, const MCSection *PSec, StringRef Name,
1833 const StringMap<const DIE *> &(DwarfUnit::*Accessor)() const) {
1834 for (const auto &NU : CUMap) {
1835 DwarfCompileUnit *TheU = NU.second;
1837 const auto &Globals = (TheU->*Accessor)();
1839 if (Globals.empty())
1842 if (auto Skeleton = static_cast<DwarfCompileUnit *>(TheU->getSkeleton()))
1844 unsigned ID = TheU->getUniqueID();
1846 // Start the dwarf pubnames section.
1847 Asm->OutStreamer.SwitchSection(PSec);
1850 Asm->OutStreamer.AddComment("Length of Public " + Name + " Info");
1851 MCSymbol *BeginLabel = Asm->GetTempSymbol("pub" + Name + "_begin", ID);
1852 MCSymbol *EndLabel = Asm->GetTempSymbol("pub" + Name + "_end", ID);
1853 Asm->EmitLabelDifference(EndLabel, BeginLabel, 4);
1855 Asm->OutStreamer.EmitLabel(BeginLabel);
1857 Asm->OutStreamer.AddComment("DWARF Version");
1858 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION);
1860 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info");
1861 Asm->EmitSectionOffset(TheU->getLabelBegin(), TheU->getSectionSym());
1863 Asm->OutStreamer.AddComment("Compilation Unit Length");
1864 Asm->EmitLabelDifference(TheU->getLabelEnd(), TheU->getLabelBegin(), 4);
1866 // Emit the pubnames for this compilation unit.
1867 for (const auto &GI : Globals) {
1868 const char *Name = GI.getKeyData();
1869 const DIE *Entity = GI.second;
1871 Asm->OutStreamer.AddComment("DIE offset");
1872 Asm->EmitInt32(Entity->getOffset());
1875 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheU, Entity);
1876 Asm->OutStreamer.AddComment(
1877 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " +
1878 dwarf::GDBIndexEntryLinkageString(Desc.Linkage));
1879 Asm->EmitInt8(Desc.toBits());
1882 Asm->OutStreamer.AddComment("External Name");
1883 Asm->OutStreamer.EmitBytes(StringRef(Name, GI.getKeyLength() + 1));
1886 Asm->OutStreamer.AddComment("End Mark");
1888 Asm->OutStreamer.EmitLabel(EndLabel);
1892 void DwarfDebug::emitDebugPubTypes(bool GnuStyle) {
1893 const MCSection *PSec =
1894 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection()
1895 : Asm->getObjFileLowering().getDwarfPubTypesSection();
1897 emitDebugPubSection(GnuStyle, PSec, "Types", &DwarfUnit::getGlobalTypes);
1900 // Emit visible names into a debug str section.
1901 void DwarfDebug::emitDebugStr() {
1902 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1903 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection());
1906 void DwarfDebug::emitDebugLocEntry(ByteStreamer &Streamer,
1907 const DebugLocEntry &Entry) {
1908 assert(Entry.getValues().size() == 1 &&
1909 "multi-value entries are not supported yet.");
1910 const DebugLocEntry::Value Value = Entry.getValues()[0];
1911 DIVariable DV(Value.getVariable());
1912 if (Value.isInt()) {
1913 DIBasicType BTy(resolve(DV.getType()));
1914 if (BTy.Verify() && (BTy.getEncoding() == dwarf::DW_ATE_signed ||
1915 BTy.getEncoding() == dwarf::DW_ATE_signed_char)) {
1916 Streamer.EmitInt8(dwarf::DW_OP_consts, "DW_OP_consts");
1917 Streamer.EmitSLEB128(Value.getInt());
1919 Streamer.EmitInt8(dwarf::DW_OP_constu, "DW_OP_constu");
1920 Streamer.EmitULEB128(Value.getInt());
1922 } else if (Value.isLocation()) {
1923 MachineLocation Loc = Value.getLoc();
1924 if (!DV.hasComplexAddress())
1926 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
1928 // Complex address entry.
1929 unsigned N = DV.getNumAddrElements();
1931 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) {
1932 if (Loc.getOffset()) {
1934 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
1935 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
1936 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
1937 Streamer.EmitSLEB128(DV.getAddrElement(1));
1939 // If first address element is OpPlus then emit
1940 // DW_OP_breg + Offset instead of DW_OP_reg + Offset.
1941 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1));
1942 Asm->EmitDwarfRegOp(Streamer, TLoc, DV.isIndirect());
1946 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
1949 // Emit remaining complex address elements.
1950 for (; i < N; ++i) {
1951 uint64_t Element = DV.getAddrElement(i);
1952 if (Element == DIBuilder::OpPlus) {
1953 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
1954 Streamer.EmitULEB128(DV.getAddrElement(++i));
1955 } else if (Element == DIBuilder::OpDeref) {
1957 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
1959 llvm_unreachable("unknown Opcode found in complex address");
1963 // else ... ignore constant fp. There is not any good way to
1964 // to represent them here in dwarf.
1968 void DwarfDebug::emitDebugLocEntryLocation(const DebugLocEntry &Entry) {
1969 Asm->OutStreamer.AddComment("Loc expr size");
1970 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol();
1971 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol();
1972 Asm->EmitLabelDifference(end, begin, 2);
1973 Asm->OutStreamer.EmitLabel(begin);
1975 APByteStreamer Streamer(*Asm);
1976 emitDebugLocEntry(Streamer, Entry);
1978 Asm->OutStreamer.EmitLabel(end);
1981 // Emit locations into the debug loc section.
1982 void DwarfDebug::emitDebugLoc() {
1983 // Start the dwarf loc section.
1984 Asm->OutStreamer.SwitchSection(
1985 Asm->getObjFileLowering().getDwarfLocSection());
1986 unsigned char Size = Asm->getDataLayout().getPointerSize();
1987 for (const auto &DebugLoc : DotDebugLocEntries) {
1988 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
1989 for (const auto &Entry : DebugLoc.List) {
1990 // Set up the range. This range is relative to the entry point of the
1991 // compile unit. This is a hard coded 0 for low_pc when we're emitting
1992 // ranges, or the DW_AT_low_pc on the compile unit otherwise.
1993 const DwarfCompileUnit *CU = Entry.getCU();
1994 if (CU->getRanges().size() == 1) {
1995 // Grab the begin symbol from the first range as our base.
1996 const MCSymbol *Base = CU->getRanges()[0].getStart();
1997 Asm->EmitLabelDifference(Entry.getBeginSym(), Base, Size);
1998 Asm->EmitLabelDifference(Entry.getEndSym(), Base, Size);
2000 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size);
2001 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size);
2004 emitDebugLocEntryLocation(Entry);
2006 Asm->OutStreamer.EmitIntValue(0, Size);
2007 Asm->OutStreamer.EmitIntValue(0, Size);
2011 void DwarfDebug::emitDebugLocDWO() {
2012 Asm->OutStreamer.SwitchSection(
2013 Asm->getObjFileLowering().getDwarfLocDWOSection());
2014 for (const auto &DebugLoc : DotDebugLocEntries) {
2015 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2016 for (const auto &Entry : DebugLoc.List) {
2017 // Just always use start_length for now - at least that's one address
2018 // rather than two. We could get fancier and try to, say, reuse an
2019 // address we know we've emitted elsewhere (the start of the function?
2020 // The start of the CU or CU subrange that encloses this range?)
2021 Asm->EmitInt8(dwarf::DW_LLE_start_length_entry);
2022 unsigned idx = AddrPool.getIndex(Entry.getBeginSym());
2023 Asm->EmitULEB128(idx);
2024 Asm->EmitLabelDifference(Entry.getEndSym(), Entry.getBeginSym(), 4);
2026 emitDebugLocEntryLocation(Entry);
2028 Asm->EmitInt8(dwarf::DW_LLE_end_of_list_entry);
2033 const MCSymbol *Start, *End;
2036 // Emit a debug aranges section, containing a CU lookup for any
2037 // address we can tie back to a CU.
2038 void DwarfDebug::emitDebugARanges() {
2039 // Start the dwarf aranges section.
2040 Asm->OutStreamer.SwitchSection(
2041 Asm->getObjFileLowering().getDwarfARangesSection());
2043 typedef DenseMap<DwarfCompileUnit *, std::vector<ArangeSpan>> SpansType;
2047 // Build a list of sections used.
2048 std::vector<const MCSection *> Sections;
2049 for (const auto &it : SectionMap) {
2050 const MCSection *Section = it.first;
2051 Sections.push_back(Section);
2054 // Sort the sections into order.
2055 // This is only done to ensure consistent output order across different runs.
2056 std::sort(Sections.begin(), Sections.end(), SectionSort);
2058 // Build a set of address spans, sorted by CU.
2059 for (const MCSection *Section : Sections) {
2060 SmallVector<SymbolCU, 8> &List = SectionMap[Section];
2061 if (List.size() < 2)
2064 // Sort the symbols by offset within the section.
2065 std::sort(List.begin(), List.end(),
2066 [&](const SymbolCU &A, const SymbolCU &B) {
2067 unsigned IA = A.Sym ? Asm->OutStreamer.GetSymbolOrder(A.Sym) : 0;
2068 unsigned IB = B.Sym ? Asm->OutStreamer.GetSymbolOrder(B.Sym) : 0;
2070 // Symbols with no order assigned should be placed at the end.
2071 // (e.g. section end labels)
2079 // If we have no section (e.g. common), just write out
2080 // individual spans for each symbol.
2082 for (const SymbolCU &Cur : List) {
2084 Span.Start = Cur.Sym;
2087 Spans[Cur.CU].push_back(Span);
2090 // Build spans between each label.
2091 const MCSymbol *StartSym = List[0].Sym;
2092 for (size_t n = 1, e = List.size(); n < e; n++) {
2093 const SymbolCU &Prev = List[n - 1];
2094 const SymbolCU &Cur = List[n];
2096 // Try and build the longest span we can within the same CU.
2097 if (Cur.CU != Prev.CU) {
2099 Span.Start = StartSym;
2101 Spans[Prev.CU].push_back(Span);
2108 unsigned PtrSize = Asm->getDataLayout().getPointerSize();
2110 // Build a list of CUs used.
2111 std::vector<DwarfCompileUnit *> CUs;
2112 for (const auto &it : Spans) {
2113 DwarfCompileUnit *CU = it.first;
2117 // Sort the CU list (again, to ensure consistent output order).
2118 std::sort(CUs.begin(), CUs.end(), [](const DwarfUnit *A, const DwarfUnit *B) {
2119 return A->getUniqueID() < B->getUniqueID();
2122 // Emit an arange table for each CU we used.
2123 for (DwarfCompileUnit *CU : CUs) {
2124 std::vector<ArangeSpan> &List = Spans[CU];
2126 // Emit size of content not including length itself.
2127 unsigned ContentSize =
2128 sizeof(int16_t) + // DWARF ARange version number
2129 sizeof(int32_t) + // Offset of CU in the .debug_info section
2130 sizeof(int8_t) + // Pointer Size (in bytes)
2131 sizeof(int8_t); // Segment Size (in bytes)
2133 unsigned TupleSize = PtrSize * 2;
2135 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple.
2137 OffsetToAlignment(sizeof(int32_t) + ContentSize, TupleSize);
2139 ContentSize += Padding;
2140 ContentSize += (List.size() + 1) * TupleSize;
2142 // For each compile unit, write the list of spans it covers.
2143 Asm->OutStreamer.AddComment("Length of ARange Set");
2144 Asm->EmitInt32(ContentSize);
2145 Asm->OutStreamer.AddComment("DWARF Arange version number");
2146 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION);
2147 Asm->OutStreamer.AddComment("Offset Into Debug Info Section");
2148 Asm->EmitSectionOffset(CU->getLocalLabelBegin(), CU->getLocalSectionSym());
2149 Asm->OutStreamer.AddComment("Address Size (in bytes)");
2150 Asm->EmitInt8(PtrSize);
2151 Asm->OutStreamer.AddComment("Segment Size (in bytes)");
2154 Asm->OutStreamer.EmitFill(Padding, 0xff);
2156 for (const ArangeSpan &Span : List) {
2157 Asm->EmitLabelReference(Span.Start, PtrSize);
2159 // Calculate the size as being from the span start to it's end.
2161 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize);
2163 // For symbols without an end marker (e.g. common), we
2164 // write a single arange entry containing just that one symbol.
2165 uint64_t Size = SymSize[Span.Start];
2169 Asm->OutStreamer.EmitIntValue(Size, PtrSize);
2173 Asm->OutStreamer.AddComment("ARange terminator");
2174 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2175 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2179 // Emit visible names into a debug ranges section.
2180 void DwarfDebug::emitDebugRanges() {
2181 // Start the dwarf ranges section.
2182 Asm->OutStreamer.SwitchSection(
2183 Asm->getObjFileLowering().getDwarfRangesSection());
2185 // Size for our labels.
2186 unsigned char Size = Asm->getDataLayout().getPointerSize();
2188 // Grab the specific ranges for the compile units in the module.
2189 for (const auto &I : CUMap) {
2190 DwarfCompileUnit *TheCU = I.second;
2192 // Iterate over the misc ranges for the compile units in the module.
2193 for (const RangeSpanList &List : TheCU->getRangeLists()) {
2194 // Emit our symbol so we can find the beginning of the range.
2195 Asm->OutStreamer.EmitLabel(List.getSym());
2197 for (const RangeSpan &Range : List.getRanges()) {
2198 const MCSymbol *Begin = Range.getStart();
2199 const MCSymbol *End = Range.getEnd();
2200 assert(Begin && "Range without a begin symbol?");
2201 assert(End && "Range without an end symbol?");
2202 if (TheCU->getRanges().size() == 1) {
2203 // Grab the begin symbol from the first range as our base.
2204 const MCSymbol *Base = TheCU->getRanges()[0].getStart();
2205 Asm->EmitLabelDifference(Begin, Base, Size);
2206 Asm->EmitLabelDifference(End, Base, Size);
2208 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2209 Asm->OutStreamer.EmitSymbolValue(End, Size);
2213 // And terminate the list with two 0 values.
2214 Asm->OutStreamer.EmitIntValue(0, Size);
2215 Asm->OutStreamer.EmitIntValue(0, Size);
2218 // Now emit a range for the CU itself.
2219 if (TheCU->getRanges().size() > 1) {
2220 Asm->OutStreamer.EmitLabel(
2221 Asm->GetTempSymbol("cu_ranges", TheCU->getUniqueID()));
2222 for (const RangeSpan &Range : TheCU->getRanges()) {
2223 const MCSymbol *Begin = Range.getStart();
2224 const MCSymbol *End = Range.getEnd();
2225 assert(Begin && "Range without a begin symbol?");
2226 assert(End && "Range without an end symbol?");
2227 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2228 Asm->OutStreamer.EmitSymbolValue(End, Size);
2230 // And terminate the list with two 0 values.
2231 Asm->OutStreamer.EmitIntValue(0, Size);
2232 Asm->OutStreamer.EmitIntValue(0, Size);
2237 // DWARF5 Experimental Separate Dwarf emitters.
2239 void DwarfDebug::initSkeletonUnit(const DwarfUnit &U, DIE &Die,
2240 std::unique_ptr<DwarfUnit> NewU) {
2241 NewU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name,
2242 U.getCUNode().getSplitDebugFilename());
2244 if (!CompilationDir.empty())
2245 NewU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
2247 addGnuPubAttributes(*NewU, Die);
2249 SkeletonHolder.addUnit(std::move(NewU));
2252 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list,
2253 // DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id,
2254 // DW_AT_addr_base, DW_AT_ranges_base.
2255 DwarfCompileUnit &DwarfDebug::constructSkeletonCU(const DwarfCompileUnit &CU) {
2257 auto OwnedUnit = make_unique<DwarfCompileUnit>(
2258 CU.getUniqueID(), CU.getCUNode(), Asm, this, &SkeletonHolder);
2259 DwarfCompileUnit &NewCU = *OwnedUnit;
2260 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
2261 DwarfInfoSectionSym);
2263 NewCU.initStmtList(DwarfLineSectionSym);
2265 initSkeletonUnit(CU, NewCU.getUnitDie(), std::move(OwnedUnit));
2270 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_dwo_name,
2272 DwarfTypeUnit &DwarfDebug::constructSkeletonTU(DwarfTypeUnit &TU) {
2273 DwarfCompileUnit &CU = static_cast<DwarfCompileUnit &>(
2274 *SkeletonHolder.getUnits()[TU.getCU().getUniqueID()]);
2276 auto OwnedUnit = make_unique<DwarfTypeUnit>(TU.getUniqueID(), CU, Asm, this,
2278 DwarfTypeUnit &NewTU = *OwnedUnit;
2279 NewTU.setTypeSignature(TU.getTypeSignature());
2280 NewTU.setType(nullptr);
2282 Asm->getObjFileLowering().getDwarfTypesSection(TU.getTypeSignature()));
2284 initSkeletonUnit(TU, NewTU.getUnitDie(), std::move(OwnedUnit));
2288 // Emit the .debug_info.dwo section for separated dwarf. This contains the
2289 // compile units that would normally be in debug_info.
2290 void DwarfDebug::emitDebugInfoDWO() {
2291 assert(useSplitDwarf() && "No split dwarf debug info?");
2292 // Don't pass an abbrev symbol, using a constant zero instead so as not to
2293 // emit relocations into the dwo file.
2294 InfoHolder.emitUnits(this, /* AbbrevSymbol */ nullptr);
2297 // Emit the .debug_abbrev.dwo section for separated dwarf. This contains the
2298 // abbreviations for the .debug_info.dwo section.
2299 void DwarfDebug::emitDebugAbbrevDWO() {
2300 assert(useSplitDwarf() && "No split dwarf?");
2301 InfoHolder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection());
2304 void DwarfDebug::emitDebugLineDWO() {
2305 assert(useSplitDwarf() && "No split dwarf?");
2306 Asm->OutStreamer.SwitchSection(
2307 Asm->getObjFileLowering().getDwarfLineDWOSection());
2308 SplitTypeUnitFileTable.Emit(Asm->OutStreamer);
2311 // Emit the .debug_str.dwo section for separated dwarf. This contains the
2312 // string section and is identical in format to traditional .debug_str
2314 void DwarfDebug::emitDebugStrDWO() {
2315 assert(useSplitDwarf() && "No split dwarf?");
2316 const MCSection *OffSec =
2317 Asm->getObjFileLowering().getDwarfStrOffDWOSection();
2318 const MCSymbol *StrSym = DwarfStrSectionSym;
2319 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(),
2323 MCDwarfDwoLineTable *DwarfDebug::getDwoLineTable(const DwarfCompileUnit &CU) {
2324 if (!useSplitDwarf())
2327 SplitTypeUnitFileTable.setCompilationDir(CU.getCUNode().getDirectory());
2328 return &SplitTypeUnitFileTable;
2331 static uint64_t makeTypeSignature(StringRef Identifier) {
2333 Hash.update(Identifier);
2334 // ... take the least significant 8 bytes and return those. Our MD5
2335 // implementation always returns its results in little endian, swap bytes
2337 MD5::MD5Result Result;
2339 return *reinterpret_cast<support::ulittle64_t *>(Result + 8);
2342 void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU,
2343 StringRef Identifier, DIE &RefDie,
2344 DICompositeType CTy) {
2345 // Fast path if we're building some type units and one has already used the
2346 // address pool we know we're going to throw away all this work anyway, so
2347 // don't bother building dependent types.
2348 if (!TypeUnitsUnderConstruction.empty() && AddrPool.hasBeenUsed())
2351 const DwarfTypeUnit *&TU = DwarfTypeUnits[CTy];
2353 CU.addDIETypeSignature(RefDie, *TU);
2357 bool TopLevelType = TypeUnitsUnderConstruction.empty();
2358 AddrPool.resetUsedFlag();
2360 auto OwnedUnit = make_unique<DwarfTypeUnit>(
2361 InfoHolder.getUnits().size() + TypeUnitsUnderConstruction.size(), CU, Asm,
2362 this, &InfoHolder, getDwoLineTable(CU));
2363 DwarfTypeUnit &NewTU = *OwnedUnit;
2364 DIE &UnitDie = NewTU.getUnitDie();
2366 TypeUnitsUnderConstruction.push_back(
2367 std::make_pair(std::move(OwnedUnit), CTy));
2369 NewTU.addUInt(UnitDie, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
2372 uint64_t Signature = makeTypeSignature(Identifier);
2373 NewTU.setTypeSignature(Signature);
2375 if (useSplitDwarf())
2376 NewTU.initSection(Asm->getObjFileLowering().getDwarfTypesDWOSection(),
2377 DwarfTypesDWOSectionSym);
2379 CU.applyStmtList(UnitDie);
2381 Asm->getObjFileLowering().getDwarfTypesSection(Signature));
2384 NewTU.setType(NewTU.createTypeDIE(CTy));
2387 auto TypeUnitsToAdd = std::move(TypeUnitsUnderConstruction);
2388 TypeUnitsUnderConstruction.clear();
2390 // Types referencing entries in the address table cannot be placed in type
2392 if (AddrPool.hasBeenUsed()) {
2394 // Remove all the types built while building this type.
2395 // This is pessimistic as some of these types might not be dependent on
2396 // the type that used an address.
2397 for (const auto &TU : TypeUnitsToAdd)
2398 DwarfTypeUnits.erase(TU.second);
2400 // Construct this type in the CU directly.
2401 // This is inefficient because all the dependent types will be rebuilt
2402 // from scratch, including building them in type units, discovering that
2403 // they depend on addresses, throwing them out and rebuilding them.
2404 CU.constructTypeDIE(RefDie, CTy);
2408 // If the type wasn't dependent on fission addresses, finish adding the type
2409 // and all its dependent types.
2410 for (auto &TU : TypeUnitsToAdd) {
2411 if (useSplitDwarf())
2412 TU.first->setSkeleton(constructSkeletonTU(*TU.first));
2413 InfoHolder.addUnit(std::move(TU.first));
2416 CU.addDIETypeSignature(RefDie, NewTU);
2419 void DwarfDebug::attachLowHighPC(DwarfCompileUnit &Unit, DIE &D,
2420 MCSymbol *Begin, MCSymbol *End) {
2421 assert(Begin && "Begin label should not be null!");
2422 assert(End && "End label should not be null!");
2423 assert(Begin->isDefined() && "Invalid starting label");
2424 assert(End->isDefined() && "Invalid end label");
2426 Unit.addLabelAddress(D, dwarf::DW_AT_low_pc, Begin);
2427 if (DwarfVersion < 4)
2428 Unit.addLabelAddress(D, dwarf::DW_AT_high_pc, End);
2430 Unit.addLabelDelta(D, dwarf::DW_AT_high_pc, End, Begin);
2433 // Accelerator table mutators - add each name along with its companion
2434 // DIE to the proper table while ensuring that the name that we're going
2435 // to reference is in the string table. We do this since the names we
2436 // add may not only be identical to the names in the DIE.
2437 void DwarfDebug::addAccelName(StringRef Name, const DIE &Die) {
2438 if (!useDwarfAccelTables())
2440 AccelNames.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2444 void DwarfDebug::addAccelObjC(StringRef Name, const DIE &Die) {
2445 if (!useDwarfAccelTables())
2447 AccelObjC.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2451 void DwarfDebug::addAccelNamespace(StringRef Name, const DIE &Die) {
2452 if (!useDwarfAccelTables())
2454 AccelNamespace.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2458 void DwarfDebug::addAccelType(StringRef Name, const DIE &Die, char Flags) {
2459 if (!useDwarfAccelTables())
2461 AccelTypes.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),