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.getOrCreateSubprogramDIE(SP);
319 attachLowHighPC(SPCU, *SPDie, FunctionBeginSym, FunctionEndSym);
321 const TargetRegisterInfo *RI = Asm->TM.getRegisterInfo();
322 MachineLocation Location(RI->getFrameRegister(*Asm->MF));
323 SPCU.addAddress(*SPDie, dwarf::DW_AT_frame_base, Location);
325 // Add name to the name table, we do this here because we're guaranteed
326 // to have concrete versions of our DW_TAG_subprogram nodes.
327 addSubprogramNames(SP, *SPDie);
332 /// Check whether we should create a DIE for the given Scope, return true
333 /// if we don't create a DIE (the corresponding DIE is null).
334 bool DwarfDebug::isLexicalScopeDIENull(LexicalScope *Scope) {
335 if (Scope->isAbstractScope())
338 // We don't create a DIE if there is no Range.
339 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges();
343 if (Ranges.size() > 1)
346 // We don't create a DIE if we have a single Range and the end label
348 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin();
349 MCSymbol *End = getLabelAfterInsn(RI->second);
353 static void addSectionLabel(AsmPrinter &Asm, DwarfUnit &U, DIE &D,
354 dwarf::Attribute A, const MCSymbol *L,
355 const MCSymbol *Sec) {
356 if (Asm.MAI->doesDwarfUseRelocationsAcrossSections())
357 U.addSectionLabel(D, A, L);
359 U.addSectionDelta(D, A, L, Sec);
362 void DwarfDebug::addScopeRangeList(DwarfCompileUnit &TheCU, DIE &ScopeDIE,
363 const SmallVectorImpl<InsnRange> &Range) {
364 // Emit offset in .debug_range as a relocatable label. emitDIE will handle
365 // emitting it appropriately.
366 MCSymbol *RangeSym = Asm->GetTempSymbol("debug_ranges", GlobalRangeCount++);
368 // Under fission, ranges are specified by constant offsets relative to the
369 // CU's DW_AT_GNU_ranges_base.
371 TheCU.addSectionDelta(ScopeDIE, dwarf::DW_AT_ranges, RangeSym,
372 DwarfDebugRangeSectionSym);
374 addSectionLabel(*Asm, TheCU, ScopeDIE, dwarf::DW_AT_ranges, RangeSym,
375 DwarfDebugRangeSectionSym);
377 RangeSpanList List(RangeSym);
378 for (const InsnRange &R : Range) {
379 RangeSpan Span(getLabelBeforeInsn(R.first), getLabelAfterInsn(R.second));
380 List.addRange(std::move(Span));
383 // Add the range list to the set of ranges to be emitted.
384 TheCU.addRangeList(std::move(List));
387 void DwarfDebug::attachRangesOrLowHighPC(DwarfCompileUnit &TheCU, DIE &Die,
388 const SmallVectorImpl<InsnRange> &Ranges) {
389 assert(!Ranges.empty());
390 if (Ranges.size() == 1)
391 attachLowHighPC(TheCU, Die, getLabelBeforeInsn(Ranges.front().first),
392 getLabelAfterInsn(Ranges.front().second));
394 addScopeRangeList(TheCU, Die, Ranges);
397 // Construct new DW_TAG_lexical_block for this scope and attach
398 // DW_AT_low_pc/DW_AT_high_pc labels.
400 DwarfDebug::constructLexicalScopeDIE(DwarfCompileUnit &TheCU,
401 LexicalScope *Scope) {
402 if (isLexicalScopeDIENull(Scope))
405 auto ScopeDIE = make_unique<DIE>(dwarf::DW_TAG_lexical_block);
406 if (Scope->isAbstractScope())
409 attachRangesOrLowHighPC(TheCU, *ScopeDIE, Scope->getRanges());
414 // This scope represents inlined body of a function. Construct DIE to
415 // represent this concrete inlined copy of the function.
417 DwarfDebug::constructInlinedScopeDIE(DwarfCompileUnit &TheCU,
418 LexicalScope *Scope) {
419 assert(Scope->getScopeNode());
420 DIScope DS(Scope->getScopeNode());
421 DISubprogram InlinedSP = getDISubprogram(DS);
422 // Find the subprogram's DwarfCompileUnit in the SPMap in case the subprogram
423 // was inlined from another compile unit.
424 DIE *OriginDIE = AbstractSPDies[InlinedSP];
425 assert(OriginDIE && "Unable to find original DIE for an inlined subprogram.");
427 auto ScopeDIE = make_unique<DIE>(dwarf::DW_TAG_inlined_subroutine);
428 TheCU.addDIEEntry(*ScopeDIE, dwarf::DW_AT_abstract_origin, *OriginDIE);
430 attachRangesOrLowHighPC(TheCU, *ScopeDIE, Scope->getRanges());
432 InlinedSubprogramDIEs.insert(OriginDIE);
434 // Add the call site information to the DIE.
435 DILocation DL(Scope->getInlinedAt());
436 TheCU.addUInt(*ScopeDIE, dwarf::DW_AT_call_file, None,
437 TheCU.getOrCreateSourceID(DL.getFilename(), DL.getDirectory()));
438 TheCU.addUInt(*ScopeDIE, dwarf::DW_AT_call_line, None, DL.getLineNumber());
440 // Add name to the name table, we do this here because we're guaranteed
441 // to have concrete versions of our DW_TAG_inlined_subprogram nodes.
442 addSubprogramNames(InlinedSP, *ScopeDIE);
447 static std::unique_ptr<DIE> constructVariableDIE(DwarfCompileUnit &TheCU,
449 const LexicalScope &Scope,
450 DIE *&ObjectPointer) {
451 auto Var = TheCU.constructVariableDIE(DV, Scope.isAbstractScope());
452 if (DV.isObjectPointer())
453 ObjectPointer = Var.get();
457 DIE *DwarfDebug::createScopeChildrenDIE(
458 DwarfCompileUnit &TheCU, LexicalScope *Scope,
459 SmallVectorImpl<std::unique_ptr<DIE>> &Children) {
460 DIE *ObjectPointer = nullptr;
462 // Collect arguments for current function.
463 if (LScopes.isCurrentFunctionScope(Scope)) {
464 for (DbgVariable *ArgDV : CurrentFnArguments)
467 constructVariableDIE(TheCU, *ArgDV, *Scope, ObjectPointer));
469 // If this is a variadic function, add an unspecified parameter.
470 DISubprogram SP(Scope->getScopeNode());
471 DIArray FnArgs = SP.getType().getTypeArray();
472 if (FnArgs.getElement(FnArgs.getNumElements() - 1)
473 .isUnspecifiedParameter()) {
475 make_unique<DIE>(dwarf::DW_TAG_unspecified_parameters));
479 // Collect lexical scope children first.
480 for (DbgVariable *DV : ScopeVariables.lookup(Scope))
481 Children.push_back(constructVariableDIE(TheCU, *DV, *Scope, ObjectPointer));
483 for (LexicalScope *LS : Scope->getChildren())
484 if (std::unique_ptr<DIE> Nested = constructScopeDIE(TheCU, LS))
485 Children.push_back(std::move(Nested));
486 return ObjectPointer;
489 void DwarfDebug::createAndAddScopeChildren(DwarfCompileUnit &TheCU,
490 LexicalScope *Scope, DIE &ScopeDIE) {
491 // We create children when the scope DIE is not null.
492 SmallVector<std::unique_ptr<DIE>, 8> Children;
493 if (DIE *ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children))
494 TheCU.addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, *ObjectPointer);
497 for (auto &I : Children)
498 ScopeDIE.addChild(std::move(I));
501 void DwarfDebug::constructAbstractSubprogramScopeDIE(DwarfCompileUnit &TheCU,
502 LexicalScope *Scope) {
503 assert(Scope && Scope->getScopeNode());
504 assert(Scope->isAbstractScope());
505 assert(!Scope->getInlinedAt());
507 DISubprogram SP(Scope->getScopeNode());
509 ProcessedSPNodes.insert(SP);
511 DIE *&AbsDef = AbstractSPDies[SP];
515 // Find the subprogram's DwarfCompileUnit in the SPMap in case the subprogram
516 // was inlined from another compile unit.
517 DwarfCompileUnit &SPCU = *SPMap[SP];
520 // Some of this is duplicated from DwarfUnit::getOrCreateSubprogramDIE, with
521 // the important distinction that the DIDescriptor is not associated with the
522 // DIE (since the DIDescriptor will be associated with the concrete DIE, if
523 // any). It could be refactored to some common utility function.
524 if (DISubprogram SPDecl = SP.getFunctionDeclaration()) {
525 ContextDIE = &SPCU.getUnitDie();
526 SPCU.getOrCreateSubprogramDIE(SPDecl);
528 ContextDIE = SPCU.getOrCreateContextDIE(resolve(SP.getContext()));
530 // Passing null as the associated DIDescriptor because the abstract definition
531 // shouldn't be found by lookup.
532 AbsDef = &SPCU.createAndAddDIE(dwarf::DW_TAG_subprogram, *ContextDIE,
534 SPCU.applySubprogramAttributes(SP, *AbsDef);
535 SPCU.addGlobalName(SP.getName(), *AbsDef, resolve(SP.getContext()));
537 SPCU.addUInt(*AbsDef, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined);
538 createAndAddScopeChildren(SPCU, Scope, *AbsDef);
541 DIE &DwarfDebug::constructSubprogramScopeDIE(DwarfCompileUnit &TheCU,
542 LexicalScope *Scope) {
543 assert(Scope && Scope->getScopeNode());
544 assert(!Scope->getInlinedAt());
545 assert(!Scope->isAbstractScope());
546 DISubprogram Sub(Scope->getScopeNode());
548 assert(Sub.isSubprogram());
550 ProcessedSPNodes.insert(Sub);
552 DIE &ScopeDIE = updateSubprogramScopeDIE(TheCU, Sub);
554 createAndAddScopeChildren(TheCU, Scope, ScopeDIE);
559 // Construct a DIE for this scope.
560 std::unique_ptr<DIE> DwarfDebug::constructScopeDIE(DwarfCompileUnit &TheCU,
561 LexicalScope *Scope) {
562 if (!Scope || !Scope->getScopeNode())
565 DIScope DS(Scope->getScopeNode());
567 assert((Scope->getInlinedAt() || !DS.isSubprogram()) &&
568 "Only handle inlined subprograms here, use "
569 "constructSubprogramScopeDIE for non-inlined "
572 SmallVector<std::unique_ptr<DIE>, 8> Children;
574 // We try to create the scope DIE first, then the children DIEs. This will
575 // avoid creating un-used children then removing them later when we find out
576 // the scope DIE is null.
577 std::unique_ptr<DIE> ScopeDIE;
578 if (Scope->getParent() && DS.isSubprogram()) {
579 ScopeDIE = constructInlinedScopeDIE(TheCU, Scope);
582 // We create children when the scope DIE is not null.
583 createScopeChildrenDIE(TheCU, Scope, Children);
585 // Early exit when we know the scope DIE is going to be null.
586 if (isLexicalScopeDIENull(Scope))
589 // We create children here when we know the scope DIE is not going to be
590 // null and the children will be added to the scope DIE.
591 createScopeChildrenDIE(TheCU, Scope, Children);
593 // There is no need to emit empty lexical block DIE.
594 std::pair<ImportedEntityMap::const_iterator,
595 ImportedEntityMap::const_iterator> Range =
596 std::equal_range(ScopesWithImportedEntities.begin(),
597 ScopesWithImportedEntities.end(),
598 std::pair<const MDNode *, const MDNode *>(DS, nullptr),
600 if (Children.empty() && Range.first == Range.second)
602 ScopeDIE = constructLexicalScopeDIE(TheCU, Scope);
603 assert(ScopeDIE && "Scope DIE should not be null.");
604 for (ImportedEntityMap::const_iterator i = Range.first; i != Range.second;
606 constructImportedEntityDIE(TheCU, i->second, *ScopeDIE);
610 for (auto &I : Children)
611 ScopeDIE->addChild(std::move(I));
616 void DwarfDebug::addGnuPubAttributes(DwarfUnit &U, DIE &D) const {
617 if (!GenerateGnuPubSections)
620 U.addFlag(D, dwarf::DW_AT_GNU_pubnames);
623 // Create new DwarfCompileUnit for the given metadata node with tag
624 // DW_TAG_compile_unit.
625 DwarfCompileUnit &DwarfDebug::constructDwarfCompileUnit(DICompileUnit DIUnit) {
626 StringRef FN = DIUnit.getFilename();
627 CompilationDir = DIUnit.getDirectory();
629 auto OwnedUnit = make_unique<DwarfCompileUnit>(
630 InfoHolder.getUnits().size(), DIUnit, Asm, this, &InfoHolder);
631 DwarfCompileUnit &NewCU = *OwnedUnit;
632 DIE &Die = NewCU.getUnitDie();
633 InfoHolder.addUnit(std::move(OwnedUnit));
635 // LTO with assembly output shares a single line table amongst multiple CUs.
636 // To avoid the compilation directory being ambiguous, let the line table
637 // explicitly describe the directory of all files, never relying on the
638 // compilation directory.
639 if (!Asm->OutStreamer.hasRawTextSupport() || SingleCU)
640 Asm->OutStreamer.getContext().setMCLineTableCompilationDir(
641 NewCU.getUniqueID(), CompilationDir);
643 NewCU.addString(Die, dwarf::DW_AT_producer, DIUnit.getProducer());
644 NewCU.addUInt(Die, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
645 DIUnit.getLanguage());
646 NewCU.addString(Die, dwarf::DW_AT_name, FN);
648 if (!useSplitDwarf()) {
649 NewCU.initStmtList(DwarfLineSectionSym);
651 // If we're using split dwarf the compilation dir is going to be in the
652 // skeleton CU and so we don't need to duplicate it here.
653 if (!CompilationDir.empty())
654 NewCU.addString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
656 addGnuPubAttributes(NewCU, Die);
659 if (DIUnit.isOptimized())
660 NewCU.addFlag(Die, dwarf::DW_AT_APPLE_optimized);
662 StringRef Flags = DIUnit.getFlags();
664 NewCU.addString(Die, dwarf::DW_AT_APPLE_flags, Flags);
666 if (unsigned RVer = DIUnit.getRunTimeVersion())
667 NewCU.addUInt(Die, dwarf::DW_AT_APPLE_major_runtime_vers,
668 dwarf::DW_FORM_data1, RVer);
673 if (useSplitDwarf()) {
674 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoDWOSection(),
675 DwarfInfoDWOSectionSym);
676 NewCU.setSkeleton(constructSkeletonCU(NewCU));
678 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
679 DwarfInfoSectionSym);
681 CUMap.insert(std::make_pair(DIUnit, &NewCU));
682 CUDieMap.insert(std::make_pair(&Die, &NewCU));
686 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
688 DIImportedEntity Module(N);
689 assert(Module.Verify());
690 if (DIE *D = TheCU.getOrCreateContextDIE(Module.getContext()))
691 constructImportedEntityDIE(TheCU, Module, *D);
694 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
695 const MDNode *N, DIE &Context) {
696 DIImportedEntity Module(N);
697 assert(Module.Verify());
698 return constructImportedEntityDIE(TheCU, Module, Context);
701 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
702 const DIImportedEntity &Module,
704 assert(Module.Verify() &&
705 "Use one of the MDNode * overloads to handle invalid metadata");
706 DIE &IMDie = TheCU.createAndAddDIE(Module.getTag(), Context, Module);
708 DIDescriptor Entity = resolve(Module.getEntity());
709 if (Entity.isNameSpace())
710 EntityDie = TheCU.getOrCreateNameSpace(DINameSpace(Entity));
711 else if (Entity.isSubprogram())
712 EntityDie = TheCU.getOrCreateSubprogramDIE(DISubprogram(Entity));
713 else if (Entity.isType())
714 EntityDie = TheCU.getOrCreateTypeDIE(DIType(Entity));
716 EntityDie = TheCU.getDIE(Entity);
717 TheCU.addSourceLine(IMDie, Module.getLineNumber(),
718 Module.getContext().getFilename(),
719 Module.getContext().getDirectory());
720 TheCU.addDIEEntry(IMDie, dwarf::DW_AT_import, *EntityDie);
721 StringRef Name = Module.getName();
723 TheCU.addString(IMDie, dwarf::DW_AT_name, Name);
726 // Emit all Dwarf sections that should come prior to the content. Create
727 // global DIEs and emit initial debug info sections. This is invoked by
728 // the target AsmPrinter.
729 void DwarfDebug::beginModule() {
730 if (DisableDebugInfoPrinting)
733 const Module *M = MMI->getModule();
735 // If module has named metadata anchors then use them, otherwise scan the
736 // module using debug info finder to collect debug info.
737 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
740 TypeIdentifierMap = generateDITypeIdentifierMap(CU_Nodes);
742 // Emit initial sections so we can reference labels later.
745 SingleCU = CU_Nodes->getNumOperands() == 1;
747 for (MDNode *N : CU_Nodes->operands()) {
748 DICompileUnit CUNode(N);
749 DwarfCompileUnit &CU = constructDwarfCompileUnit(CUNode);
750 DIArray ImportedEntities = CUNode.getImportedEntities();
751 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
752 ScopesWithImportedEntities.push_back(std::make_pair(
753 DIImportedEntity(ImportedEntities.getElement(i)).getContext(),
754 ImportedEntities.getElement(i)));
755 std::sort(ScopesWithImportedEntities.begin(),
756 ScopesWithImportedEntities.end(), less_first());
757 DIArray GVs = CUNode.getGlobalVariables();
758 for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i)
759 CU.createGlobalVariableDIE(DIGlobalVariable(GVs.getElement(i)));
760 DIArray SPs = CUNode.getSubprograms();
761 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i)
762 SPMap.insert(std::make_pair(SPs.getElement(i), &CU));
763 DIArray EnumTypes = CUNode.getEnumTypes();
764 for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i)
765 CU.getOrCreateTypeDIE(EnumTypes.getElement(i));
766 DIArray RetainedTypes = CUNode.getRetainedTypes();
767 for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i) {
768 DIType Ty(RetainedTypes.getElement(i));
769 // The retained types array by design contains pointers to
770 // MDNodes rather than DIRefs. Unique them here.
771 DIType UniqueTy(resolve(Ty.getRef()));
772 CU.getOrCreateTypeDIE(UniqueTy);
774 // Emit imported_modules last so that the relevant context is already
776 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
777 constructImportedEntityDIE(CU, ImportedEntities.getElement(i));
780 // Tell MMI that we have debug info.
781 MMI->setDebugInfoAvailability(true);
783 // Prime section data.
784 SectionMap[Asm->getObjFileLowering().getTextSection()];
787 void DwarfDebug::finishSubprogramDefinitions() {
788 const Module *M = MMI->getModule();
790 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
791 for (MDNode *N : CU_Nodes->operands()) {
792 DICompileUnit TheCU(N);
793 // Construct subprogram DIE and add variables DIEs.
794 DwarfCompileUnit *SPCU =
795 static_cast<DwarfCompileUnit *>(CUMap.lookup(TheCU));
796 DIArray Subprograms = TheCU.getSubprograms();
797 for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) {
798 DISubprogram SP(Subprograms.getElement(i));
799 // Perhaps the subprogram is in another CU (such as due to comdat
800 // folding, etc), in which case ignore it here.
801 if (SPMap[SP] != SPCU)
803 DIE *D = SPCU->getDIE(SP);
804 if (DIE *AbsSPDIE = AbstractSPDies.lookup(SP)) {
806 // If this subprogram has an abstract definition, reference that
807 SPCU->addDIEEntry(*D, dwarf::DW_AT_abstract_origin, *AbsSPDIE);
810 // Lazily construct the subprogram if we didn't see either concrete or
811 // inlined versions during codegen.
812 D = SPCU->getOrCreateSubprogramDIE(SP);
813 // And attach the attributes
814 SPCU->applySubprogramAttributes(SP, *D);
815 SPCU->addGlobalName(SP.getName(), *D, resolve(SP.getContext()));
822 // Collect info for variables that were optimized out.
823 void DwarfDebug::collectDeadVariables() {
824 const Module *M = MMI->getModule();
826 if (NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu")) {
827 for (MDNode *N : CU_Nodes->operands()) {
828 DICompileUnit TheCU(N);
829 // Construct subprogram DIE and add variables DIEs.
830 DwarfCompileUnit *SPCU =
831 static_cast<DwarfCompileUnit *>(CUMap.lookup(TheCU));
832 assert(SPCU && "Unable to find Compile Unit!");
833 DIArray Subprograms = TheCU.getSubprograms();
834 for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) {
835 DISubprogram SP(Subprograms.getElement(i));
836 if (ProcessedSPNodes.count(SP) != 0)
838 assert(SP.isSubprogram() &&
839 "CU's subprogram list contains a non-subprogram");
840 assert(SP.isDefinition() &&
841 "CU's subprogram list contains a subprogram declaration");
842 DIArray Variables = SP.getVariables();
843 if (Variables.getNumElements() == 0)
846 DIE *SPDIE = AbstractSPDies.lookup(SP);
848 SPDIE = SPCU->getDIE(SP);
850 for (unsigned vi = 0, ve = Variables.getNumElements(); vi != ve; ++vi) {
851 DIVariable DV(Variables.getElement(vi));
852 assert(DV.isVariable());
853 DbgVariable NewVar(DV, nullptr, this);
854 SPDIE->addChild(SPCU->constructVariableDIE(NewVar));
861 void DwarfDebug::finalizeModuleInfo() {
862 finishSubprogramDefinitions();
864 // Collect info for variables that were optimized out.
865 collectDeadVariables();
867 // Handle anything that needs to be done on a per-unit basis after
868 // all other generation.
869 for (const auto &TheU : getUnits()) {
870 // Emit DW_AT_containing_type attribute to connect types with their
871 // vtable holding type.
872 TheU->constructContainingTypeDIEs();
874 // Add CU specific attributes if we need to add any.
875 if (TheU->getUnitDie().getTag() == dwarf::DW_TAG_compile_unit) {
876 // If we're splitting the dwarf out now that we've got the entire
877 // CU then add the dwo id to it.
878 DwarfCompileUnit *SkCU =
879 static_cast<DwarfCompileUnit *>(TheU->getSkeleton());
880 if (useSplitDwarf()) {
881 // Emit a unique identifier for this CU.
882 uint64_t ID = DIEHash(Asm).computeCUSignature(TheU->getUnitDie());
883 TheU->addUInt(TheU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
884 dwarf::DW_FORM_data8, ID);
885 SkCU->addUInt(SkCU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
886 dwarf::DW_FORM_data8, ID);
888 // We don't keep track of which addresses are used in which CU so this
889 // is a bit pessimistic under LTO.
890 if (!AddrPool.isEmpty())
891 addSectionLabel(*Asm, *SkCU, SkCU->getUnitDie(),
892 dwarf::DW_AT_GNU_addr_base, DwarfAddrSectionSym,
893 DwarfAddrSectionSym);
894 if (!TheU->getRangeLists().empty())
895 addSectionLabel(*Asm, *SkCU, SkCU->getUnitDie(),
896 dwarf::DW_AT_GNU_ranges_base,
897 DwarfDebugRangeSectionSym, DwarfDebugRangeSectionSym);
900 // If we have code split among multiple sections or non-contiguous
901 // ranges of code then emit a DW_AT_ranges attribute on the unit that will
902 // remain in the .o file, otherwise add a DW_AT_low_pc.
903 // FIXME: We should use ranges allow reordering of code ala
904 // .subsections_via_symbols in mach-o. This would mean turning on
905 // ranges for all subprogram DIEs for mach-o.
906 DwarfCompileUnit &U =
907 SkCU ? *SkCU : static_cast<DwarfCompileUnit &>(*TheU);
908 unsigned NumRanges = TheU->getRanges().size();
911 addSectionLabel(*Asm, U, U.getUnitDie(), dwarf::DW_AT_ranges,
912 Asm->GetTempSymbol("cu_ranges", U.getUniqueID()),
913 DwarfDebugRangeSectionSym);
915 // A DW_AT_low_pc attribute may also be specified in combination with
916 // DW_AT_ranges to specify the default base address for use in
917 // location lists (see Section 2.6.2) and range lists (see Section
919 U.addUInt(U.getUnitDie(), dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr,
922 RangeSpan &Range = TheU->getRanges().back();
923 U.addLocalLabelAddress(U.getUnitDie(), dwarf::DW_AT_low_pc,
925 U.addLabelDelta(U.getUnitDie(), dwarf::DW_AT_high_pc, Range.getEnd(),
932 // Compute DIE offsets and sizes.
933 InfoHolder.computeSizeAndOffsets();
935 SkeletonHolder.computeSizeAndOffsets();
938 void DwarfDebug::endSections() {
939 // Filter labels by section.
940 for (const SymbolCU &SCU : ArangeLabels) {
941 if (SCU.Sym->isInSection()) {
942 // Make a note of this symbol and it's section.
943 const MCSection *Section = &SCU.Sym->getSection();
944 if (!Section->getKind().isMetadata())
945 SectionMap[Section].push_back(SCU);
947 // Some symbols (e.g. common/bss on mach-o) can have no section but still
948 // appear in the output. This sucks as we rely on sections to build
949 // arange spans. We can do it without, but it's icky.
950 SectionMap[nullptr].push_back(SCU);
954 // Build a list of sections used.
955 std::vector<const MCSection *> Sections;
956 for (const auto &it : SectionMap) {
957 const MCSection *Section = it.first;
958 Sections.push_back(Section);
961 // Sort the sections into order.
962 // This is only done to ensure consistent output order across different runs.
963 std::sort(Sections.begin(), Sections.end(), SectionSort);
965 // Add terminating symbols for each section.
966 for (unsigned ID = 0, E = Sections.size(); ID != E; ID++) {
967 const MCSection *Section = Sections[ID];
968 MCSymbol *Sym = nullptr;
971 // We can't call MCSection::getLabelEndName, as it's only safe to do so
972 // if we know the section name up-front. For user-created sections, the
973 // resulting label may not be valid to use as a label. (section names can
974 // use a greater set of characters on some systems)
975 Sym = Asm->GetTempSymbol("debug_end", ID);
976 Asm->OutStreamer.SwitchSection(Section);
977 Asm->OutStreamer.EmitLabel(Sym);
980 // Insert a final terminator.
981 SectionMap[Section].push_back(SymbolCU(nullptr, Sym));
985 // Emit all Dwarf sections that should come after the content.
986 void DwarfDebug::endModule() {
987 assert(CurFn == nullptr);
988 assert(CurMI == nullptr);
993 // End any existing sections.
994 // TODO: Does this need to happen?
997 // Finalize the debug info for the module.
998 finalizeModuleInfo();
1002 // Emit all the DIEs into a debug info section.
1005 // Corresponding abbreviations into a abbrev section.
1006 emitAbbreviations();
1008 // Emit info into a debug aranges section.
1009 if (GenerateARangeSection)
1012 // Emit info into a debug ranges section.
1015 if (useSplitDwarf()) {
1018 emitDebugAbbrevDWO();
1020 // Emit DWO addresses.
1021 AddrPool.emit(*Asm, Asm->getObjFileLowering().getDwarfAddrSection());
1024 // Emit info into a debug loc section.
1027 // Emit info into the dwarf accelerator table sections.
1028 if (useDwarfAccelTables()) {
1031 emitAccelNamespaces();
1035 // Emit the pubnames and pubtypes sections if requested.
1036 if (HasDwarfPubSections) {
1037 emitDebugPubNames(GenerateGnuPubSections);
1038 emitDebugPubTypes(GenerateGnuPubSections);
1043 AbstractVariables.clear();
1045 // Reset these for the next Module if we have one.
1049 // Find abstract variable, if any, associated with Var.
1050 DbgVariable *DwarfDebug::findAbstractVariable(DIVariable &DV,
1051 DebugLoc ScopeLoc) {
1052 return findAbstractVariable(DV, ScopeLoc.getScope(DV->getContext()));
1055 DbgVariable *DwarfDebug::findAbstractVariable(DIVariable &DV,
1056 const MDNode *ScopeNode) {
1057 LLVMContext &Ctx = DV->getContext();
1058 // More then one inlined variable corresponds to one abstract variable.
1059 DIVariable Var = cleanseInlinedVariable(DV, Ctx);
1060 auto I = AbstractVariables.find(Var);
1061 if (I != AbstractVariables.end())
1062 return I->second.get();
1064 LexicalScope *Scope = LScopes.findAbstractScope(ScopeNode);
1068 auto AbsDbgVariable = make_unique<DbgVariable>(Var, nullptr, this);
1069 addScopeVariable(Scope, AbsDbgVariable.get());
1070 return (AbstractVariables[Var] = std::move(AbsDbgVariable)).get();
1073 // If Var is a current function argument then add it to CurrentFnArguments list.
1074 bool DwarfDebug::addCurrentFnArgument(DbgVariable *Var, LexicalScope *Scope) {
1075 if (!LScopes.isCurrentFunctionScope(Scope))
1077 DIVariable DV = Var->getVariable();
1078 if (DV.getTag() != dwarf::DW_TAG_arg_variable)
1080 unsigned ArgNo = DV.getArgNumber();
1084 size_t Size = CurrentFnArguments.size();
1086 CurrentFnArguments.resize(CurFn->getFunction()->arg_size());
1087 // llvm::Function argument size is not good indicator of how many
1088 // arguments does the function have at source level.
1090 CurrentFnArguments.resize(ArgNo * 2);
1091 CurrentFnArguments[ArgNo - 1] = Var;
1095 // Collect variable information from side table maintained by MMI.
1096 void DwarfDebug::collectVariableInfoFromMMITable(
1097 SmallPtrSet<const MDNode *, 16> &Processed) {
1098 for (const auto &VI : MMI->getVariableDbgInfo()) {
1101 Processed.insert(VI.Var);
1102 DIVariable DV(VI.Var);
1103 LexicalScope *Scope = LScopes.findLexicalScope(VI.Loc);
1105 // If variable scope is not found then skip this variable.
1109 DbgVariable *AbsDbgVariable = findAbstractVariable(DV, VI.Loc);
1110 DbgVariable *RegVar = new DbgVariable(DV, AbsDbgVariable, this);
1111 RegVar->setFrameIndex(VI.Slot);
1112 if (!addCurrentFnArgument(RegVar, Scope))
1113 addScopeVariable(Scope, RegVar);
1117 // Get .debug_loc entry for the instruction range starting at MI.
1118 static DebugLocEntry::Value getDebugLocValue(const MachineInstr *MI) {
1119 const MDNode *Var = MI->getDebugVariable();
1121 assert(MI->getNumOperands() == 3);
1122 if (MI->getOperand(0).isReg()) {
1123 MachineLocation MLoc;
1124 // If the second operand is an immediate, this is a
1125 // register-indirect address.
1126 if (!MI->getOperand(1).isImm())
1127 MLoc.set(MI->getOperand(0).getReg());
1129 MLoc.set(MI->getOperand(0).getReg(), MI->getOperand(1).getImm());
1130 return DebugLocEntry::Value(Var, MLoc);
1132 if (MI->getOperand(0).isImm())
1133 return DebugLocEntry::Value(Var, MI->getOperand(0).getImm());
1134 if (MI->getOperand(0).isFPImm())
1135 return DebugLocEntry::Value(Var, MI->getOperand(0).getFPImm());
1136 if (MI->getOperand(0).isCImm())
1137 return DebugLocEntry::Value(Var, MI->getOperand(0).getCImm());
1139 llvm_unreachable("Unexpected 3 operand DBG_VALUE instruction!");
1142 // Find variables for each lexical scope.
1144 DwarfDebug::collectVariableInfo(SmallPtrSet<const MDNode *, 16> &Processed) {
1145 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1146 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1148 // Grab the variable info that was squirreled away in the MMI side-table.
1149 collectVariableInfoFromMMITable(Processed);
1151 for (const auto &I : DbgValues) {
1152 DIVariable DV(I.first);
1153 if (Processed.count(DV))
1156 // Instruction ranges, specifying where DV is accessible.
1157 const auto &Ranges = I.second;
1161 LexicalScope *Scope = nullptr;
1162 if (DV.getTag() == dwarf::DW_TAG_arg_variable &&
1163 DISubprogram(DV.getContext()).describes(CurFn->getFunction()))
1164 Scope = LScopes.getCurrentFunctionScope();
1165 else if (MDNode *IA = DV.getInlinedAt()) {
1166 DebugLoc DL = DebugLoc::getFromDILocation(IA);
1167 Scope = LScopes.findInlinedScope(DebugLoc::get(
1168 DL.getLine(), DL.getCol(), DV.getContext(), IA));
1170 Scope = LScopes.findLexicalScope(DV.getContext());
1171 // If variable scope is not found then skip this variable.
1175 Processed.insert(DV);
1176 const MachineInstr *MInsn = Ranges.front().first;
1177 assert(MInsn->isDebugValue() && "History must begin with debug value");
1178 DbgVariable *AbsVar = findAbstractVariable(DV, MInsn->getDebugLoc());
1179 DbgVariable *RegVar = new DbgVariable(DV, AbsVar, this);
1180 if (!addCurrentFnArgument(RegVar, Scope))
1181 addScopeVariable(Scope, RegVar);
1183 AbsVar->setMInsn(MInsn);
1185 // Check if the first DBG_VALUE is valid for the rest of the function.
1186 if (Ranges.size() == 1 && Ranges.front().second == nullptr) {
1187 RegVar->setMInsn(MInsn);
1191 // Handle multiple DBG_VALUE instructions describing one variable.
1192 RegVar->setDotDebugLocOffset(DotDebugLocEntries.size());
1194 DotDebugLocEntries.resize(DotDebugLocEntries.size() + 1);
1195 DebugLocList &LocList = DotDebugLocEntries.back();
1197 Asm->GetTempSymbol("debug_loc", DotDebugLocEntries.size() - 1);
1198 SmallVector<DebugLocEntry, 4> &DebugLoc = LocList.List;
1199 for (auto I = Ranges.begin(), E = Ranges.end(); I != E; ++I) {
1200 const MachineInstr *Begin = I->first;
1201 const MachineInstr *End = I->second;
1202 assert(Begin->isDebugValue() && "Invalid History entry");
1204 // Check if a variable is unaccessible in this range.
1205 if (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() &&
1206 !Begin->getOperand(0).getReg())
1209 const MCSymbol *StartLabel = getLabelBeforeInsn(Begin);
1210 assert(StartLabel && "Forgot label before DBG_VALUE starting a range!");
1212 const MCSymbol *EndLabel;
1214 EndLabel = getLabelAfterInsn(End);
1215 else if (std::next(I) == Ranges.end())
1216 EndLabel = FunctionEndSym;
1218 EndLabel = getLabelBeforeInsn(std::next(I)->first);
1219 assert(EndLabel && "Forgot label after instruction ending a range!");
1221 DEBUG(dbgs() << "DotDebugLoc Pair:\n"
1222 << "\t" << *Begin << "\t" << *End << "\n");
1223 DebugLocEntry Loc(StartLabel, EndLabel, getDebugLocValue(Begin), TheCU);
1224 if (DebugLoc.empty() || !DebugLoc.back().Merge(Loc))
1225 DebugLoc.push_back(std::move(Loc));
1229 // Collect info for variables that were optimized out.
1230 DIArray Variables = DISubprogram(FnScope->getScopeNode()).getVariables();
1231 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1232 DIVariable DV(Variables.getElement(i));
1233 assert(DV.isVariable());
1234 if (!Processed.insert(DV))
1236 if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext()))
1239 new DbgVariable(DV, findAbstractVariable(DV, Scope->getScopeNode()),
1244 // Return Label preceding the instruction.
1245 MCSymbol *DwarfDebug::getLabelBeforeInsn(const MachineInstr *MI) {
1246 MCSymbol *Label = LabelsBeforeInsn.lookup(MI);
1247 assert(Label && "Didn't insert label before instruction");
1251 // Return Label immediately following the instruction.
1252 MCSymbol *DwarfDebug::getLabelAfterInsn(const MachineInstr *MI) {
1253 return LabelsAfterInsn.lookup(MI);
1256 // Process beginning of an instruction.
1257 void DwarfDebug::beginInstruction(const MachineInstr *MI) {
1258 assert(CurMI == nullptr);
1260 // Check if source location changes, but ignore DBG_VALUE locations.
1261 if (!MI->isDebugValue()) {
1262 DebugLoc DL = MI->getDebugLoc();
1263 if (DL != PrevInstLoc && (!DL.isUnknown() || UnknownLocations)) {
1266 if (DL == PrologEndLoc) {
1267 Flags |= DWARF2_FLAG_PROLOGUE_END;
1268 PrologEndLoc = DebugLoc();
1270 if (PrologEndLoc.isUnknown())
1271 Flags |= DWARF2_FLAG_IS_STMT;
1273 if (!DL.isUnknown()) {
1274 const MDNode *Scope = DL.getScope(Asm->MF->getFunction()->getContext());
1275 recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags);
1277 recordSourceLine(0, 0, nullptr, 0);
1281 // Insert labels where requested.
1282 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1283 LabelsBeforeInsn.find(MI);
1286 if (I == LabelsBeforeInsn.end())
1289 // Label already assigned.
1294 PrevLabel = MMI->getContext().CreateTempSymbol();
1295 Asm->OutStreamer.EmitLabel(PrevLabel);
1297 I->second = PrevLabel;
1300 // Process end of an instruction.
1301 void DwarfDebug::endInstruction() {
1302 assert(CurMI != nullptr);
1303 // Don't create a new label after DBG_VALUE instructions.
1304 // They don't generate code.
1305 if (!CurMI->isDebugValue())
1306 PrevLabel = nullptr;
1308 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1309 LabelsAfterInsn.find(CurMI);
1313 if (I == LabelsAfterInsn.end())
1316 // Label already assigned.
1320 // We need a label after this instruction.
1322 PrevLabel = MMI->getContext().CreateTempSymbol();
1323 Asm->OutStreamer.EmitLabel(PrevLabel);
1325 I->second = PrevLabel;
1328 // Each LexicalScope has first instruction and last instruction to mark
1329 // beginning and end of a scope respectively. Create an inverse map that list
1330 // scopes starts (and ends) with an instruction. One instruction may start (or
1331 // end) multiple scopes. Ignore scopes that are not reachable.
1332 void DwarfDebug::identifyScopeMarkers() {
1333 SmallVector<LexicalScope *, 4> WorkList;
1334 WorkList.push_back(LScopes.getCurrentFunctionScope());
1335 while (!WorkList.empty()) {
1336 LexicalScope *S = WorkList.pop_back_val();
1338 const SmallVectorImpl<LexicalScope *> &Children = S->getChildren();
1339 if (!Children.empty())
1340 WorkList.append(Children.begin(), Children.end());
1342 if (S->isAbstractScope())
1345 for (const InsnRange &R : S->getRanges()) {
1346 assert(R.first && "InsnRange does not have first instruction!");
1347 assert(R.second && "InsnRange does not have second instruction!");
1348 requestLabelBeforeInsn(R.first);
1349 requestLabelAfterInsn(R.second);
1354 static DebugLoc findPrologueEndLoc(const MachineFunction *MF) {
1355 // First known non-DBG_VALUE and non-frame setup location marks
1356 // the beginning of the function body.
1357 for (const auto &MBB : *MF)
1358 for (const auto &MI : MBB)
1359 if (!MI.isDebugValue() && !MI.getFlag(MachineInstr::FrameSetup) &&
1360 !MI.getDebugLoc().isUnknown())
1361 return MI.getDebugLoc();
1365 // Gather pre-function debug information. Assumes being called immediately
1366 // after the function entry point has been emitted.
1367 void DwarfDebug::beginFunction(const MachineFunction *MF) {
1370 // If there's no debug info for the function we're not going to do anything.
1371 if (!MMI->hasDebugInfo())
1374 // Grab the lexical scopes for the function, if we don't have any of those
1375 // then we're not going to be able to do anything.
1376 LScopes.initialize(*MF);
1377 if (LScopes.empty())
1380 assert(DbgValues.empty() && "DbgValues map wasn't cleaned!");
1382 // Make sure that each lexical scope will have a begin/end label.
1383 identifyScopeMarkers();
1385 // Set DwarfDwarfCompileUnitID in MCContext to the Compile Unit this function
1386 // belongs to so that we add to the correct per-cu line table in the
1388 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1389 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1390 assert(TheCU && "Unable to find compile unit!");
1391 if (Asm->OutStreamer.hasRawTextSupport())
1392 // Use a single line table if we are generating assembly.
1393 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1395 Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID());
1397 // Emit a label for the function so that we have a beginning address.
1398 FunctionBeginSym = Asm->GetTempSymbol("func_begin", Asm->getFunctionNumber());
1399 // Assumes in correct section after the entry point.
1400 Asm->OutStreamer.EmitLabel(FunctionBeginSym);
1402 // Calculate history for local variables.
1403 calculateDbgValueHistory(MF, Asm->TM.getRegisterInfo(), DbgValues);
1405 // Request labels for the full history.
1406 for (const auto &I : DbgValues) {
1407 const auto &Ranges = I.second;
1411 // The first mention of a function argument gets the FunctionBeginSym
1412 // label, so arguments are visible when breaking at function entry.
1413 DIVariable DV(I.first);
1414 if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable &&
1415 getDISubprogram(DV.getContext()).describes(MF->getFunction()))
1416 LabelsBeforeInsn[Ranges.front().first] = FunctionBeginSym;
1418 for (const auto &Range : Ranges) {
1419 requestLabelBeforeInsn(Range.first);
1421 requestLabelAfterInsn(Range.second);
1425 PrevInstLoc = DebugLoc();
1426 PrevLabel = FunctionBeginSym;
1428 // Record beginning of function.
1429 PrologEndLoc = findPrologueEndLoc(MF);
1430 if (!PrologEndLoc.isUnknown()) {
1431 DebugLoc FnStartDL =
1432 PrologEndLoc.getFnDebugLoc(MF->getFunction()->getContext());
1434 FnStartDL.getLine(), FnStartDL.getCol(),
1435 FnStartDL.getScope(MF->getFunction()->getContext()),
1436 // We'd like to list the prologue as "not statements" but GDB behaves
1437 // poorly if we do that. Revisit this with caution/GDB (7.5+) testing.
1438 DWARF2_FLAG_IS_STMT);
1442 void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) {
1443 SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS];
1444 DIVariable DV = Var->getVariable();
1445 // Variables with positive arg numbers are parameters.
1446 if (unsigned ArgNum = DV.getArgNumber()) {
1447 // Keep all parameters in order at the start of the variable list to ensure
1448 // function types are correct (no out-of-order parameters)
1450 // This could be improved by only doing it for optimized builds (unoptimized
1451 // builds have the right order to begin with), searching from the back (this
1452 // would catch the unoptimized case quickly), or doing a binary search
1453 // rather than linear search.
1454 SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin();
1455 while (I != Vars.end()) {
1456 unsigned CurNum = (*I)->getVariable().getArgNumber();
1457 // A local (non-parameter) variable has been found, insert immediately
1461 // A later indexed parameter has been found, insert immediately before it.
1462 if (CurNum > ArgNum)
1466 Vars.insert(I, Var);
1470 Vars.push_back(Var);
1473 // Gather and emit post-function debug information.
1474 void DwarfDebug::endFunction(const MachineFunction *MF) {
1475 // Every beginFunction(MF) call should be followed by an endFunction(MF) call,
1476 // though the beginFunction may not be called at all.
1477 // We should handle both cases.
1481 assert(CurFn == MF);
1482 assert(CurFn != nullptr);
1484 if (!MMI->hasDebugInfo() || LScopes.empty()) {
1485 // If we don't have a lexical scope for this function then there will
1486 // be a hole in the range information. Keep note of this by setting the
1487 // previously used section to nullptr.
1488 PrevSection = nullptr;
1494 // Define end label for subprogram.
1495 FunctionEndSym = Asm->GetTempSymbol("func_end", Asm->getFunctionNumber());
1496 // Assumes in correct section after the entry point.
1497 Asm->OutStreamer.EmitLabel(FunctionEndSym);
1499 // Set DwarfDwarfCompileUnitID in MCContext to default value.
1500 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1502 SmallPtrSet<const MDNode *, 16> ProcessedVars;
1503 collectVariableInfo(ProcessedVars);
1505 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1506 DwarfCompileUnit &TheCU = *SPMap.lookup(FnScope->getScopeNode());
1508 // Construct abstract scopes.
1509 for (LexicalScope *AScope : LScopes.getAbstractScopesList()) {
1510 DISubprogram SP(AScope->getScopeNode());
1511 if (!SP.isSubprogram())
1513 // Collect info for variables that were optimized out.
1514 DIArray Variables = SP.getVariables();
1515 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1516 DIVariable DV(Variables.getElement(i));
1517 assert(DV && DV.isVariable());
1518 if (!ProcessedVars.insert(DV))
1520 findAbstractVariable(DV, DV.getContext());
1522 constructAbstractSubprogramScopeDIE(TheCU, AScope);
1525 DIE &CurFnDIE = constructSubprogramScopeDIE(TheCU, FnScope);
1526 if (!CurFn->getTarget().Options.DisableFramePointerElim(*CurFn))
1527 TheCU.addFlag(CurFnDIE, dwarf::DW_AT_APPLE_omit_frame_ptr);
1529 // Add the range of this function to the list of ranges for the CU.
1530 RangeSpan Span(FunctionBeginSym, FunctionEndSym);
1531 TheCU.addRange(std::move(Span));
1532 PrevSection = Asm->getCurrentSection();
1536 // Ownership of DbgVariables is a bit subtle - ScopeVariables owns all the
1537 // DbgVariables except those that are also in AbstractVariables (since they
1538 // can be used cross-function)
1539 for (const auto &I : ScopeVariables)
1540 for (const auto *Var : I.second)
1541 if (!AbstractVariables.count(Var->getVariable()) || Var->getAbstractVariable())
1543 ScopeVariables.clear();
1544 DeleteContainerPointers(CurrentFnArguments);
1546 LabelsBeforeInsn.clear();
1547 LabelsAfterInsn.clear();
1548 PrevLabel = nullptr;
1552 // Register a source line with debug info. Returns the unique label that was
1553 // emitted and which provides correspondence to the source line list.
1554 void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S,
1559 unsigned Discriminator = 0;
1560 if (DIScope Scope = DIScope(S)) {
1561 assert(Scope.isScope());
1562 Fn = Scope.getFilename();
1563 Dir = Scope.getDirectory();
1564 if (Scope.isLexicalBlock())
1565 Discriminator = DILexicalBlock(S).getDiscriminator();
1567 unsigned CUID = Asm->OutStreamer.getContext().getDwarfCompileUnitID();
1568 Src = static_cast<DwarfCompileUnit &>(*InfoHolder.getUnits()[CUID])
1569 .getOrCreateSourceID(Fn, Dir);
1571 Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0,
1575 //===----------------------------------------------------------------------===//
1577 //===----------------------------------------------------------------------===//
1579 // Emit initial Dwarf sections with a label at the start of each one.
1580 void DwarfDebug::emitSectionLabels() {
1581 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
1583 // Dwarf sections base addresses.
1584 DwarfInfoSectionSym =
1585 emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info");
1586 if (useSplitDwarf())
1587 DwarfInfoDWOSectionSym =
1588 emitSectionSym(Asm, TLOF.getDwarfInfoDWOSection(), "section_info_dwo");
1589 DwarfAbbrevSectionSym =
1590 emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev");
1591 if (useSplitDwarf())
1592 DwarfAbbrevDWOSectionSym = emitSectionSym(
1593 Asm, TLOF.getDwarfAbbrevDWOSection(), "section_abbrev_dwo");
1594 if (GenerateARangeSection)
1595 emitSectionSym(Asm, TLOF.getDwarfARangesSection());
1597 DwarfLineSectionSym =
1598 emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line");
1599 if (GenerateGnuPubSections) {
1600 DwarfGnuPubNamesSectionSym =
1601 emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection());
1602 DwarfGnuPubTypesSectionSym =
1603 emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection());
1604 } else if (HasDwarfPubSections) {
1605 emitSectionSym(Asm, TLOF.getDwarfPubNamesSection());
1606 emitSectionSym(Asm, TLOF.getDwarfPubTypesSection());
1609 DwarfStrSectionSym =
1610 emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string");
1611 if (useSplitDwarf()) {
1612 DwarfStrDWOSectionSym =
1613 emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string");
1614 DwarfAddrSectionSym =
1615 emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec");
1616 DwarfDebugLocSectionSym =
1617 emitSectionSym(Asm, TLOF.getDwarfLocDWOSection(), "skel_loc");
1619 DwarfDebugLocSectionSym =
1620 emitSectionSym(Asm, TLOF.getDwarfLocSection(), "section_debug_loc");
1621 DwarfDebugRangeSectionSym =
1622 emitSectionSym(Asm, TLOF.getDwarfRangesSection(), "debug_range");
1625 // Recursively emits a debug information entry.
1626 void DwarfDebug::emitDIE(DIE &Die) {
1627 // Get the abbreviation for this DIE.
1628 const DIEAbbrev &Abbrev = Die.getAbbrev();
1630 // Emit the code (index) for the abbreviation.
1631 if (Asm->isVerbose())
1632 Asm->OutStreamer.AddComment("Abbrev [" + Twine(Abbrev.getNumber()) +
1633 "] 0x" + Twine::utohexstr(Die.getOffset()) +
1634 ":0x" + Twine::utohexstr(Die.getSize()) + " " +
1635 dwarf::TagString(Abbrev.getTag()));
1636 Asm->EmitULEB128(Abbrev.getNumber());
1638 const SmallVectorImpl<DIEValue *> &Values = Die.getValues();
1639 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
1641 // Emit the DIE attribute values.
1642 for (unsigned i = 0, N = Values.size(); i < N; ++i) {
1643 dwarf::Attribute Attr = AbbrevData[i].getAttribute();
1644 dwarf::Form Form = AbbrevData[i].getForm();
1645 assert(Form && "Too many attributes for DIE (check abbreviation)");
1647 if (Asm->isVerbose()) {
1648 Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr));
1649 if (Attr == dwarf::DW_AT_accessibility)
1650 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(
1651 cast<DIEInteger>(Values[i])->getValue()));
1654 // Emit an attribute using the defined form.
1655 Values[i]->EmitValue(Asm, Form);
1658 // Emit the DIE children if any.
1659 if (Abbrev.hasChildren()) {
1660 for (auto &Child : Die.getChildren())
1663 Asm->OutStreamer.AddComment("End Of Children Mark");
1668 // Emit the debug info section.
1669 void DwarfDebug::emitDebugInfo() {
1670 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1672 Holder.emitUnits(this, DwarfAbbrevSectionSym);
1675 // Emit the abbreviation section.
1676 void DwarfDebug::emitAbbreviations() {
1677 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1679 Holder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection());
1682 // Emit the last address of the section and the end of the line matrix.
1683 void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) {
1684 // Define last address of section.
1685 Asm->OutStreamer.AddComment("Extended Op");
1688 Asm->OutStreamer.AddComment("Op size");
1689 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1);
1690 Asm->OutStreamer.AddComment("DW_LNE_set_address");
1691 Asm->EmitInt8(dwarf::DW_LNE_set_address);
1693 Asm->OutStreamer.AddComment("Section end label");
1695 Asm->OutStreamer.EmitSymbolValue(
1696 Asm->GetTempSymbol("section_end", SectionEnd),
1697 Asm->getDataLayout().getPointerSize());
1699 // Mark end of matrix.
1700 Asm->OutStreamer.AddComment("DW_LNE_end_sequence");
1706 // Emit visible names into a hashed accelerator table section.
1707 void DwarfDebug::emitAccelNames() {
1708 AccelNames.FinalizeTable(Asm, "Names");
1709 Asm->OutStreamer.SwitchSection(
1710 Asm->getObjFileLowering().getDwarfAccelNamesSection());
1711 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin");
1712 Asm->OutStreamer.EmitLabel(SectionBegin);
1714 // Emit the full data.
1715 AccelNames.Emit(Asm, SectionBegin, &InfoHolder);
1718 // Emit objective C classes and categories into a hashed accelerator table
1720 void DwarfDebug::emitAccelObjC() {
1721 AccelObjC.FinalizeTable(Asm, "ObjC");
1722 Asm->OutStreamer.SwitchSection(
1723 Asm->getObjFileLowering().getDwarfAccelObjCSection());
1724 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin");
1725 Asm->OutStreamer.EmitLabel(SectionBegin);
1727 // Emit the full data.
1728 AccelObjC.Emit(Asm, SectionBegin, &InfoHolder);
1731 // Emit namespace dies into a hashed accelerator table.
1732 void DwarfDebug::emitAccelNamespaces() {
1733 AccelNamespace.FinalizeTable(Asm, "namespac");
1734 Asm->OutStreamer.SwitchSection(
1735 Asm->getObjFileLowering().getDwarfAccelNamespaceSection());
1736 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin");
1737 Asm->OutStreamer.EmitLabel(SectionBegin);
1739 // Emit the full data.
1740 AccelNamespace.Emit(Asm, SectionBegin, &InfoHolder);
1743 // Emit type dies into a hashed accelerator table.
1744 void DwarfDebug::emitAccelTypes() {
1746 AccelTypes.FinalizeTable(Asm, "types");
1747 Asm->OutStreamer.SwitchSection(
1748 Asm->getObjFileLowering().getDwarfAccelTypesSection());
1749 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin");
1750 Asm->OutStreamer.EmitLabel(SectionBegin);
1752 // Emit the full data.
1753 AccelTypes.Emit(Asm, SectionBegin, &InfoHolder);
1756 // Public name handling.
1757 // The format for the various pubnames:
1759 // dwarf pubnames - offset/name pairs where the offset is the offset into the CU
1760 // for the DIE that is named.
1762 // gnu pubnames - offset/index value/name tuples where the offset is the offset
1763 // into the CU and the index value is computed according to the type of value
1764 // for the DIE that is named.
1766 // For type units the offset is the offset of the skeleton DIE. For split dwarf
1767 // it's the offset within the debug_info/debug_types dwo section, however, the
1768 // reference in the pubname header doesn't change.
1770 /// computeIndexValue - Compute the gdb index value for the DIE and CU.
1771 static dwarf::PubIndexEntryDescriptor computeIndexValue(DwarfUnit *CU,
1773 dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC;
1775 // We could have a specification DIE that has our most of our knowledge,
1776 // look for that now.
1777 DIEValue *SpecVal = Die->findAttribute(dwarf::DW_AT_specification);
1779 DIE &SpecDIE = cast<DIEEntry>(SpecVal)->getEntry();
1780 if (SpecDIE.findAttribute(dwarf::DW_AT_external))
1781 Linkage = dwarf::GIEL_EXTERNAL;
1782 } else if (Die->findAttribute(dwarf::DW_AT_external))
1783 Linkage = dwarf::GIEL_EXTERNAL;
1785 switch (Die->getTag()) {
1786 case dwarf::DW_TAG_class_type:
1787 case dwarf::DW_TAG_structure_type:
1788 case dwarf::DW_TAG_union_type:
1789 case dwarf::DW_TAG_enumeration_type:
1790 return dwarf::PubIndexEntryDescriptor(
1791 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus
1792 ? dwarf::GIEL_STATIC
1793 : dwarf::GIEL_EXTERNAL);
1794 case dwarf::DW_TAG_typedef:
1795 case dwarf::DW_TAG_base_type:
1796 case dwarf::DW_TAG_subrange_type:
1797 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC);
1798 case dwarf::DW_TAG_namespace:
1799 return dwarf::GIEK_TYPE;
1800 case dwarf::DW_TAG_subprogram:
1801 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage);
1802 case dwarf::DW_TAG_constant:
1803 case dwarf::DW_TAG_variable:
1804 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage);
1805 case dwarf::DW_TAG_enumerator:
1806 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE,
1807 dwarf::GIEL_STATIC);
1809 return dwarf::GIEK_NONE;
1813 /// emitDebugPubNames - Emit visible names into a debug pubnames section.
1815 void DwarfDebug::emitDebugPubNames(bool GnuStyle) {
1816 const MCSection *PSec =
1817 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection()
1818 : Asm->getObjFileLowering().getDwarfPubNamesSection();
1820 emitDebugPubSection(GnuStyle, PSec, "Names", &DwarfUnit::getGlobalNames);
1823 void DwarfDebug::emitDebugPubSection(
1824 bool GnuStyle, const MCSection *PSec, StringRef Name,
1825 const StringMap<const DIE *> &(DwarfUnit::*Accessor)() const) {
1826 for (const auto &NU : CUMap) {
1827 DwarfCompileUnit *TheU = NU.second;
1829 const auto &Globals = (TheU->*Accessor)();
1831 if (Globals.empty())
1834 if (auto Skeleton = static_cast<DwarfCompileUnit *>(TheU->getSkeleton()))
1836 unsigned ID = TheU->getUniqueID();
1838 // Start the dwarf pubnames section.
1839 Asm->OutStreamer.SwitchSection(PSec);
1842 Asm->OutStreamer.AddComment("Length of Public " + Name + " Info");
1843 MCSymbol *BeginLabel = Asm->GetTempSymbol("pub" + Name + "_begin", ID);
1844 MCSymbol *EndLabel = Asm->GetTempSymbol("pub" + Name + "_end", ID);
1845 Asm->EmitLabelDifference(EndLabel, BeginLabel, 4);
1847 Asm->OutStreamer.EmitLabel(BeginLabel);
1849 Asm->OutStreamer.AddComment("DWARF Version");
1850 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION);
1852 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info");
1853 Asm->EmitSectionOffset(TheU->getLabelBegin(), TheU->getSectionSym());
1855 Asm->OutStreamer.AddComment("Compilation Unit Length");
1856 Asm->EmitLabelDifference(TheU->getLabelEnd(), TheU->getLabelBegin(), 4);
1858 // Emit the pubnames for this compilation unit.
1859 for (const auto &GI : Globals) {
1860 const char *Name = GI.getKeyData();
1861 const DIE *Entity = GI.second;
1863 Asm->OutStreamer.AddComment("DIE offset");
1864 Asm->EmitInt32(Entity->getOffset());
1867 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheU, Entity);
1868 Asm->OutStreamer.AddComment(
1869 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " +
1870 dwarf::GDBIndexEntryLinkageString(Desc.Linkage));
1871 Asm->EmitInt8(Desc.toBits());
1874 Asm->OutStreamer.AddComment("External Name");
1875 Asm->OutStreamer.EmitBytes(StringRef(Name, GI.getKeyLength() + 1));
1878 Asm->OutStreamer.AddComment("End Mark");
1880 Asm->OutStreamer.EmitLabel(EndLabel);
1884 void DwarfDebug::emitDebugPubTypes(bool GnuStyle) {
1885 const MCSection *PSec =
1886 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection()
1887 : Asm->getObjFileLowering().getDwarfPubTypesSection();
1889 emitDebugPubSection(GnuStyle, PSec, "Types", &DwarfUnit::getGlobalTypes);
1892 // Emit visible names into a debug str section.
1893 void DwarfDebug::emitDebugStr() {
1894 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1895 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection());
1898 void DwarfDebug::emitDebugLocEntry(ByteStreamer &Streamer,
1899 const DebugLocEntry &Entry) {
1900 assert(Entry.getValues().size() == 1 &&
1901 "multi-value entries are not supported yet.");
1902 const DebugLocEntry::Value Value = Entry.getValues()[0];
1903 DIVariable DV(Value.getVariable());
1904 if (Value.isInt()) {
1905 DIBasicType BTy(resolve(DV.getType()));
1906 if (BTy.Verify() && (BTy.getEncoding() == dwarf::DW_ATE_signed ||
1907 BTy.getEncoding() == dwarf::DW_ATE_signed_char)) {
1908 Streamer.EmitInt8(dwarf::DW_OP_consts, "DW_OP_consts");
1909 Streamer.EmitSLEB128(Value.getInt());
1911 Streamer.EmitInt8(dwarf::DW_OP_constu, "DW_OP_constu");
1912 Streamer.EmitULEB128(Value.getInt());
1914 } else if (Value.isLocation()) {
1915 MachineLocation Loc = Value.getLoc();
1916 if (!DV.hasComplexAddress())
1918 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
1920 // Complex address entry.
1921 unsigned N = DV.getNumAddrElements();
1923 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) {
1924 if (Loc.getOffset()) {
1926 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
1927 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
1928 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
1929 Streamer.EmitSLEB128(DV.getAddrElement(1));
1931 // If first address element is OpPlus then emit
1932 // DW_OP_breg + Offset instead of DW_OP_reg + Offset.
1933 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1));
1934 Asm->EmitDwarfRegOp(Streamer, TLoc, DV.isIndirect());
1938 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
1941 // Emit remaining complex address elements.
1942 for (; i < N; ++i) {
1943 uint64_t Element = DV.getAddrElement(i);
1944 if (Element == DIBuilder::OpPlus) {
1945 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
1946 Streamer.EmitULEB128(DV.getAddrElement(++i));
1947 } else if (Element == DIBuilder::OpDeref) {
1949 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
1951 llvm_unreachable("unknown Opcode found in complex address");
1955 // else ... ignore constant fp. There is not any good way to
1956 // to represent them here in dwarf.
1960 void DwarfDebug::emitDebugLocEntryLocation(const DebugLocEntry &Entry) {
1961 Asm->OutStreamer.AddComment("Loc expr size");
1962 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol();
1963 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol();
1964 Asm->EmitLabelDifference(end, begin, 2);
1965 Asm->OutStreamer.EmitLabel(begin);
1967 APByteStreamer Streamer(*Asm);
1968 emitDebugLocEntry(Streamer, Entry);
1970 Asm->OutStreamer.EmitLabel(end);
1973 // Emit locations into the debug loc section.
1974 void DwarfDebug::emitDebugLoc() {
1975 // Start the dwarf loc section.
1976 Asm->OutStreamer.SwitchSection(
1977 Asm->getObjFileLowering().getDwarfLocSection());
1978 unsigned char Size = Asm->getDataLayout().getPointerSize();
1979 for (const auto &DebugLoc : DotDebugLocEntries) {
1980 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
1981 for (const auto &Entry : DebugLoc.List) {
1982 // Set up the range. This range is relative to the entry point of the
1983 // compile unit. This is a hard coded 0 for low_pc when we're emitting
1984 // ranges, or the DW_AT_low_pc on the compile unit otherwise.
1985 const DwarfCompileUnit *CU = Entry.getCU();
1986 if (CU->getRanges().size() == 1) {
1987 // Grab the begin symbol from the first range as our base.
1988 const MCSymbol *Base = CU->getRanges()[0].getStart();
1989 Asm->EmitLabelDifference(Entry.getBeginSym(), Base, Size);
1990 Asm->EmitLabelDifference(Entry.getEndSym(), Base, Size);
1992 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size);
1993 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size);
1996 emitDebugLocEntryLocation(Entry);
1998 Asm->OutStreamer.EmitIntValue(0, Size);
1999 Asm->OutStreamer.EmitIntValue(0, Size);
2003 void DwarfDebug::emitDebugLocDWO() {
2004 Asm->OutStreamer.SwitchSection(
2005 Asm->getObjFileLowering().getDwarfLocDWOSection());
2006 for (const auto &DebugLoc : DotDebugLocEntries) {
2007 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2008 for (const auto &Entry : DebugLoc.List) {
2009 // Just always use start_length for now - at least that's one address
2010 // rather than two. We could get fancier and try to, say, reuse an
2011 // address we know we've emitted elsewhere (the start of the function?
2012 // The start of the CU or CU subrange that encloses this range?)
2013 Asm->EmitInt8(dwarf::DW_LLE_start_length_entry);
2014 unsigned idx = AddrPool.getIndex(Entry.getBeginSym());
2015 Asm->EmitULEB128(idx);
2016 Asm->EmitLabelDifference(Entry.getEndSym(), Entry.getBeginSym(), 4);
2018 emitDebugLocEntryLocation(Entry);
2020 Asm->EmitInt8(dwarf::DW_LLE_end_of_list_entry);
2025 const MCSymbol *Start, *End;
2028 // Emit a debug aranges section, containing a CU lookup for any
2029 // address we can tie back to a CU.
2030 void DwarfDebug::emitDebugARanges() {
2031 // Start the dwarf aranges section.
2032 Asm->OutStreamer.SwitchSection(
2033 Asm->getObjFileLowering().getDwarfARangesSection());
2035 typedef DenseMap<DwarfCompileUnit *, std::vector<ArangeSpan>> SpansType;
2039 // Build a list of sections used.
2040 std::vector<const MCSection *> Sections;
2041 for (const auto &it : SectionMap) {
2042 const MCSection *Section = it.first;
2043 Sections.push_back(Section);
2046 // Sort the sections into order.
2047 // This is only done to ensure consistent output order across different runs.
2048 std::sort(Sections.begin(), Sections.end(), SectionSort);
2050 // Build a set of address spans, sorted by CU.
2051 for (const MCSection *Section : Sections) {
2052 SmallVector<SymbolCU, 8> &List = SectionMap[Section];
2053 if (List.size() < 2)
2056 // Sort the symbols by offset within the section.
2057 std::sort(List.begin(), List.end(),
2058 [&](const SymbolCU &A, const SymbolCU &B) {
2059 unsigned IA = A.Sym ? Asm->OutStreamer.GetSymbolOrder(A.Sym) : 0;
2060 unsigned IB = B.Sym ? Asm->OutStreamer.GetSymbolOrder(B.Sym) : 0;
2062 // Symbols with no order assigned should be placed at the end.
2063 // (e.g. section end labels)
2071 // If we have no section (e.g. common), just write out
2072 // individual spans for each symbol.
2074 for (const SymbolCU &Cur : List) {
2076 Span.Start = Cur.Sym;
2079 Spans[Cur.CU].push_back(Span);
2082 // Build spans between each label.
2083 const MCSymbol *StartSym = List[0].Sym;
2084 for (size_t n = 1, e = List.size(); n < e; n++) {
2085 const SymbolCU &Prev = List[n - 1];
2086 const SymbolCU &Cur = List[n];
2088 // Try and build the longest span we can within the same CU.
2089 if (Cur.CU != Prev.CU) {
2091 Span.Start = StartSym;
2093 Spans[Prev.CU].push_back(Span);
2100 unsigned PtrSize = Asm->getDataLayout().getPointerSize();
2102 // Build a list of CUs used.
2103 std::vector<DwarfCompileUnit *> CUs;
2104 for (const auto &it : Spans) {
2105 DwarfCompileUnit *CU = it.first;
2109 // Sort the CU list (again, to ensure consistent output order).
2110 std::sort(CUs.begin(), CUs.end(), [](const DwarfUnit *A, const DwarfUnit *B) {
2111 return A->getUniqueID() < B->getUniqueID();
2114 // Emit an arange table for each CU we used.
2115 for (DwarfCompileUnit *CU : CUs) {
2116 std::vector<ArangeSpan> &List = Spans[CU];
2118 // Emit size of content not including length itself.
2119 unsigned ContentSize =
2120 sizeof(int16_t) + // DWARF ARange version number
2121 sizeof(int32_t) + // Offset of CU in the .debug_info section
2122 sizeof(int8_t) + // Pointer Size (in bytes)
2123 sizeof(int8_t); // Segment Size (in bytes)
2125 unsigned TupleSize = PtrSize * 2;
2127 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple.
2129 OffsetToAlignment(sizeof(int32_t) + ContentSize, TupleSize);
2131 ContentSize += Padding;
2132 ContentSize += (List.size() + 1) * TupleSize;
2134 // For each compile unit, write the list of spans it covers.
2135 Asm->OutStreamer.AddComment("Length of ARange Set");
2136 Asm->EmitInt32(ContentSize);
2137 Asm->OutStreamer.AddComment("DWARF Arange version number");
2138 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION);
2139 Asm->OutStreamer.AddComment("Offset Into Debug Info Section");
2140 Asm->EmitSectionOffset(CU->getLocalLabelBegin(), CU->getLocalSectionSym());
2141 Asm->OutStreamer.AddComment("Address Size (in bytes)");
2142 Asm->EmitInt8(PtrSize);
2143 Asm->OutStreamer.AddComment("Segment Size (in bytes)");
2146 Asm->OutStreamer.EmitFill(Padding, 0xff);
2148 for (const ArangeSpan &Span : List) {
2149 Asm->EmitLabelReference(Span.Start, PtrSize);
2151 // Calculate the size as being from the span start to it's end.
2153 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize);
2155 // For symbols without an end marker (e.g. common), we
2156 // write a single arange entry containing just that one symbol.
2157 uint64_t Size = SymSize[Span.Start];
2161 Asm->OutStreamer.EmitIntValue(Size, PtrSize);
2165 Asm->OutStreamer.AddComment("ARange terminator");
2166 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2167 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2171 // Emit visible names into a debug ranges section.
2172 void DwarfDebug::emitDebugRanges() {
2173 // Start the dwarf ranges section.
2174 Asm->OutStreamer.SwitchSection(
2175 Asm->getObjFileLowering().getDwarfRangesSection());
2177 // Size for our labels.
2178 unsigned char Size = Asm->getDataLayout().getPointerSize();
2180 // Grab the specific ranges for the compile units in the module.
2181 for (const auto &I : CUMap) {
2182 DwarfCompileUnit *TheCU = I.second;
2184 // Iterate over the misc ranges for the compile units in the module.
2185 for (const RangeSpanList &List : TheCU->getRangeLists()) {
2186 // Emit our symbol so we can find the beginning of the range.
2187 Asm->OutStreamer.EmitLabel(List.getSym());
2189 for (const RangeSpan &Range : List.getRanges()) {
2190 const MCSymbol *Begin = Range.getStart();
2191 const MCSymbol *End = Range.getEnd();
2192 assert(Begin && "Range without a begin symbol?");
2193 assert(End && "Range without an end symbol?");
2194 if (TheCU->getRanges().size() == 1) {
2195 // Grab the begin symbol from the first range as our base.
2196 const MCSymbol *Base = TheCU->getRanges()[0].getStart();
2197 Asm->EmitLabelDifference(Begin, Base, Size);
2198 Asm->EmitLabelDifference(End, Base, Size);
2200 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2201 Asm->OutStreamer.EmitSymbolValue(End, Size);
2205 // And terminate the list with two 0 values.
2206 Asm->OutStreamer.EmitIntValue(0, Size);
2207 Asm->OutStreamer.EmitIntValue(0, Size);
2210 // Now emit a range for the CU itself.
2211 if (TheCU->getRanges().size() > 1) {
2212 Asm->OutStreamer.EmitLabel(
2213 Asm->GetTempSymbol("cu_ranges", TheCU->getUniqueID()));
2214 for (const RangeSpan &Range : TheCU->getRanges()) {
2215 const MCSymbol *Begin = Range.getStart();
2216 const MCSymbol *End = Range.getEnd();
2217 assert(Begin && "Range without a begin symbol?");
2218 assert(End && "Range without an end symbol?");
2219 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2220 Asm->OutStreamer.EmitSymbolValue(End, Size);
2222 // And terminate the list with two 0 values.
2223 Asm->OutStreamer.EmitIntValue(0, Size);
2224 Asm->OutStreamer.EmitIntValue(0, Size);
2229 // DWARF5 Experimental Separate Dwarf emitters.
2231 void DwarfDebug::initSkeletonUnit(const DwarfUnit &U, DIE &Die,
2232 std::unique_ptr<DwarfUnit> NewU) {
2233 NewU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name,
2234 U.getCUNode().getSplitDebugFilename());
2236 if (!CompilationDir.empty())
2237 NewU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
2239 addGnuPubAttributes(*NewU, Die);
2241 SkeletonHolder.addUnit(std::move(NewU));
2244 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list,
2245 // DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id,
2246 // DW_AT_addr_base, DW_AT_ranges_base.
2247 DwarfCompileUnit &DwarfDebug::constructSkeletonCU(const DwarfCompileUnit &CU) {
2249 auto OwnedUnit = make_unique<DwarfCompileUnit>(
2250 CU.getUniqueID(), CU.getCUNode(), Asm, this, &SkeletonHolder);
2251 DwarfCompileUnit &NewCU = *OwnedUnit;
2252 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
2253 DwarfInfoSectionSym);
2255 NewCU.initStmtList(DwarfLineSectionSym);
2257 initSkeletonUnit(CU, NewCU.getUnitDie(), std::move(OwnedUnit));
2262 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_dwo_name,
2264 DwarfTypeUnit &DwarfDebug::constructSkeletonTU(DwarfTypeUnit &TU) {
2265 DwarfCompileUnit &CU = static_cast<DwarfCompileUnit &>(
2266 *SkeletonHolder.getUnits()[TU.getCU().getUniqueID()]);
2268 auto OwnedUnit = make_unique<DwarfTypeUnit>(TU.getUniqueID(), CU, Asm, this,
2270 DwarfTypeUnit &NewTU = *OwnedUnit;
2271 NewTU.setTypeSignature(TU.getTypeSignature());
2272 NewTU.setType(nullptr);
2274 Asm->getObjFileLowering().getDwarfTypesSection(TU.getTypeSignature()));
2276 initSkeletonUnit(TU, NewTU.getUnitDie(), std::move(OwnedUnit));
2280 // Emit the .debug_info.dwo section for separated dwarf. This contains the
2281 // compile units that would normally be in debug_info.
2282 void DwarfDebug::emitDebugInfoDWO() {
2283 assert(useSplitDwarf() && "No split dwarf debug info?");
2284 // Don't pass an abbrev symbol, using a constant zero instead so as not to
2285 // emit relocations into the dwo file.
2286 InfoHolder.emitUnits(this, /* AbbrevSymbol */ nullptr);
2289 // Emit the .debug_abbrev.dwo section for separated dwarf. This contains the
2290 // abbreviations for the .debug_info.dwo section.
2291 void DwarfDebug::emitDebugAbbrevDWO() {
2292 assert(useSplitDwarf() && "No split dwarf?");
2293 InfoHolder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection());
2296 void DwarfDebug::emitDebugLineDWO() {
2297 assert(useSplitDwarf() && "No split dwarf?");
2298 Asm->OutStreamer.SwitchSection(
2299 Asm->getObjFileLowering().getDwarfLineDWOSection());
2300 SplitTypeUnitFileTable.Emit(Asm->OutStreamer);
2303 // Emit the .debug_str.dwo section for separated dwarf. This contains the
2304 // string section and is identical in format to traditional .debug_str
2306 void DwarfDebug::emitDebugStrDWO() {
2307 assert(useSplitDwarf() && "No split dwarf?");
2308 const MCSection *OffSec =
2309 Asm->getObjFileLowering().getDwarfStrOffDWOSection();
2310 const MCSymbol *StrSym = DwarfStrSectionSym;
2311 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(),
2315 MCDwarfDwoLineTable *DwarfDebug::getDwoLineTable(const DwarfCompileUnit &CU) {
2316 if (!useSplitDwarf())
2319 SplitTypeUnitFileTable.setCompilationDir(CU.getCUNode().getDirectory());
2320 return &SplitTypeUnitFileTable;
2323 static uint64_t makeTypeSignature(StringRef Identifier) {
2325 Hash.update(Identifier);
2326 // ... take the least significant 8 bytes and return those. Our MD5
2327 // implementation always returns its results in little endian, swap bytes
2329 MD5::MD5Result Result;
2331 return *reinterpret_cast<support::ulittle64_t *>(Result + 8);
2334 void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU,
2335 StringRef Identifier, DIE &RefDie,
2336 DICompositeType CTy) {
2337 // Fast path if we're building some type units and one has already used the
2338 // address pool we know we're going to throw away all this work anyway, so
2339 // don't bother building dependent types.
2340 if (!TypeUnitsUnderConstruction.empty() && AddrPool.hasBeenUsed())
2343 const DwarfTypeUnit *&TU = DwarfTypeUnits[CTy];
2345 CU.addDIETypeSignature(RefDie, *TU);
2349 bool TopLevelType = TypeUnitsUnderConstruction.empty();
2350 AddrPool.resetUsedFlag();
2353 make_unique<DwarfTypeUnit>(InfoHolder.getUnits().size(), CU, Asm, this,
2354 &InfoHolder, getDwoLineTable(CU));
2355 DwarfTypeUnit &NewTU = *OwnedUnit;
2356 DIE &UnitDie = NewTU.getUnitDie();
2358 TypeUnitsUnderConstruction.push_back(
2359 std::make_pair(std::move(OwnedUnit), CTy));
2361 NewTU.addUInt(UnitDie, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
2364 uint64_t Signature = makeTypeSignature(Identifier);
2365 NewTU.setTypeSignature(Signature);
2367 if (!useSplitDwarf())
2368 CU.applyStmtList(UnitDie);
2370 // FIXME: Skip using COMDAT groups for type units in the .dwo file once tools
2371 // such as DWP ( http://gcc.gnu.org/wiki/DebugFissionDWP ) can cope with it.
2374 ? Asm->getObjFileLowering().getDwarfTypesDWOSection(Signature)
2375 : Asm->getObjFileLowering().getDwarfTypesSection(Signature));
2377 NewTU.setType(NewTU.createTypeDIE(CTy));
2380 auto TypeUnitsToAdd = std::move(TypeUnitsUnderConstruction);
2381 TypeUnitsUnderConstruction.clear();
2383 // Types referencing entries in the address table cannot be placed in type
2385 if (AddrPool.hasBeenUsed()) {
2387 // Remove all the types built while building this type.
2388 // This is pessimistic as some of these types might not be dependent on
2389 // the type that used an address.
2390 for (const auto &TU : TypeUnitsToAdd)
2391 DwarfTypeUnits.erase(TU.second);
2393 // Construct this type in the CU directly.
2394 // This is inefficient because all the dependent types will be rebuilt
2395 // from scratch, including building them in type units, discovering that
2396 // they depend on addresses, throwing them out and rebuilding them.
2397 CU.constructTypeDIE(RefDie, CTy);
2401 // If the type wasn't dependent on fission addresses, finish adding the type
2402 // and all its dependent types.
2403 for (auto &TU : TypeUnitsToAdd) {
2404 if (useSplitDwarf())
2405 TU.first->setSkeleton(constructSkeletonTU(*TU.first));
2406 InfoHolder.addUnit(std::move(TU.first));
2409 CU.addDIETypeSignature(RefDie, NewTU);
2412 void DwarfDebug::attachLowHighPC(DwarfCompileUnit &Unit, DIE &D,
2413 MCSymbol *Begin, MCSymbol *End) {
2414 assert(Begin && "Begin label should not be null!");
2415 assert(End && "End label should not be null!");
2416 assert(Begin->isDefined() && "Invalid starting label");
2417 assert(End->isDefined() && "Invalid end label");
2419 Unit.addLabelAddress(D, dwarf::DW_AT_low_pc, Begin);
2420 if (DwarfVersion < 4)
2421 Unit.addLabelAddress(D, dwarf::DW_AT_high_pc, End);
2423 Unit.addLabelDelta(D, dwarf::DW_AT_high_pc, End, Begin);
2426 // Accelerator table mutators - add each name along with its companion
2427 // DIE to the proper table while ensuring that the name that we're going
2428 // to reference is in the string table. We do this since the names we
2429 // add may not only be identical to the names in the DIE.
2430 void DwarfDebug::addAccelName(StringRef Name, const DIE &Die) {
2431 if (!useDwarfAccelTables())
2433 AccelNames.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2437 void DwarfDebug::addAccelObjC(StringRef Name, const DIE &Die) {
2438 if (!useDwarfAccelTables())
2440 AccelObjC.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2444 void DwarfDebug::addAccelNamespace(StringRef Name, const DIE &Die) {
2445 if (!useDwarfAccelTables())
2447 AccelNamespace.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2451 void DwarfDebug::addAccelType(StringRef Name, const DIE &Die, char Flags) {
2452 if (!useDwarfAccelTables())
2454 AccelTypes.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),