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.applySubprogramAttributesToDefinition(SP, *AbsDef);
536 SPCU.addUInt(*AbsDef, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined);
537 createAndAddScopeChildren(SPCU, Scope, *AbsDef);
540 DIE &DwarfDebug::constructSubprogramScopeDIE(DwarfCompileUnit &TheCU,
541 LexicalScope *Scope) {
542 assert(Scope && Scope->getScopeNode());
543 assert(!Scope->getInlinedAt());
544 assert(!Scope->isAbstractScope());
545 DISubprogram Sub(Scope->getScopeNode());
547 assert(Sub.isSubprogram());
549 ProcessedSPNodes.insert(Sub);
551 DIE &ScopeDIE = updateSubprogramScopeDIE(TheCU, Sub);
553 createAndAddScopeChildren(TheCU, Scope, ScopeDIE);
558 // Construct a DIE for this scope.
559 std::unique_ptr<DIE> DwarfDebug::constructScopeDIE(DwarfCompileUnit &TheCU,
560 LexicalScope *Scope) {
561 if (!Scope || !Scope->getScopeNode())
564 DIScope DS(Scope->getScopeNode());
566 assert((Scope->getInlinedAt() || !DS.isSubprogram()) &&
567 "Only handle inlined subprograms here, use "
568 "constructSubprogramScopeDIE for non-inlined "
571 SmallVector<std::unique_ptr<DIE>, 8> Children;
573 // We try to create the scope DIE first, then the children DIEs. This will
574 // avoid creating un-used children then removing them later when we find out
575 // the scope DIE is null.
576 std::unique_ptr<DIE> ScopeDIE;
577 if (Scope->getParent() && DS.isSubprogram()) {
578 ScopeDIE = constructInlinedScopeDIE(TheCU, Scope);
581 // We create children when the scope DIE is not null.
582 createScopeChildrenDIE(TheCU, Scope, Children);
584 // Early exit when we know the scope DIE is going to be null.
585 if (isLexicalScopeDIENull(Scope))
588 // We create children here when we know the scope DIE is not going to be
589 // null and the children will be added to the scope DIE.
590 createScopeChildrenDIE(TheCU, Scope, Children);
592 // There is no need to emit empty lexical block DIE.
593 std::pair<ImportedEntityMap::const_iterator,
594 ImportedEntityMap::const_iterator> Range =
595 std::equal_range(ScopesWithImportedEntities.begin(),
596 ScopesWithImportedEntities.end(),
597 std::pair<const MDNode *, const MDNode *>(DS, nullptr),
599 if (Children.empty() && Range.first == Range.second)
601 ScopeDIE = constructLexicalScopeDIE(TheCU, Scope);
602 assert(ScopeDIE && "Scope DIE should not be null.");
603 for (ImportedEntityMap::const_iterator i = Range.first; i != Range.second;
605 constructImportedEntityDIE(TheCU, i->second, *ScopeDIE);
609 for (auto &I : Children)
610 ScopeDIE->addChild(std::move(I));
615 void DwarfDebug::addGnuPubAttributes(DwarfUnit &U, DIE &D) const {
616 if (!GenerateGnuPubSections)
619 U.addFlag(D, dwarf::DW_AT_GNU_pubnames);
622 // Create new DwarfCompileUnit for the given metadata node with tag
623 // DW_TAG_compile_unit.
624 DwarfCompileUnit &DwarfDebug::constructDwarfCompileUnit(DICompileUnit DIUnit) {
625 StringRef FN = DIUnit.getFilename();
626 CompilationDir = DIUnit.getDirectory();
628 auto OwnedUnit = make_unique<DwarfCompileUnit>(
629 InfoHolder.getUnits().size(), DIUnit, Asm, this, &InfoHolder);
630 DwarfCompileUnit &NewCU = *OwnedUnit;
631 DIE &Die = NewCU.getUnitDie();
632 InfoHolder.addUnit(std::move(OwnedUnit));
634 // LTO with assembly output shares a single line table amongst multiple CUs.
635 // To avoid the compilation directory being ambiguous, let the line table
636 // explicitly describe the directory of all files, never relying on the
637 // compilation directory.
638 if (!Asm->OutStreamer.hasRawTextSupport() || SingleCU)
639 Asm->OutStreamer.getContext().setMCLineTableCompilationDir(
640 NewCU.getUniqueID(), CompilationDir);
642 NewCU.addString(Die, dwarf::DW_AT_producer, DIUnit.getProducer());
643 NewCU.addUInt(Die, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
644 DIUnit.getLanguage());
645 NewCU.addString(Die, dwarf::DW_AT_name, FN);
647 if (!useSplitDwarf()) {
648 NewCU.initStmtList(DwarfLineSectionSym);
650 // If we're using split dwarf the compilation dir is going to be in the
651 // skeleton CU and so we don't need to duplicate it here.
652 if (!CompilationDir.empty())
653 NewCU.addString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
655 addGnuPubAttributes(NewCU, Die);
658 if (DIUnit.isOptimized())
659 NewCU.addFlag(Die, dwarf::DW_AT_APPLE_optimized);
661 StringRef Flags = DIUnit.getFlags();
663 NewCU.addString(Die, dwarf::DW_AT_APPLE_flags, Flags);
665 if (unsigned RVer = DIUnit.getRunTimeVersion())
666 NewCU.addUInt(Die, dwarf::DW_AT_APPLE_major_runtime_vers,
667 dwarf::DW_FORM_data1, RVer);
672 if (useSplitDwarf()) {
673 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoDWOSection(),
674 DwarfInfoDWOSectionSym);
675 NewCU.setSkeleton(constructSkeletonCU(NewCU));
677 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
678 DwarfInfoSectionSym);
680 CUMap.insert(std::make_pair(DIUnit, &NewCU));
681 CUDieMap.insert(std::make_pair(&Die, &NewCU));
685 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
687 DIImportedEntity Module(N);
688 assert(Module.Verify());
689 if (DIE *D = TheCU.getOrCreateContextDIE(Module.getContext()))
690 constructImportedEntityDIE(TheCU, Module, *D);
693 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
694 const MDNode *N, DIE &Context) {
695 DIImportedEntity Module(N);
696 assert(Module.Verify());
697 return constructImportedEntityDIE(TheCU, Module, Context);
700 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
701 const DIImportedEntity &Module,
703 assert(Module.Verify() &&
704 "Use one of the MDNode * overloads to handle invalid metadata");
705 DIE &IMDie = TheCU.createAndAddDIE(Module.getTag(), Context, Module);
707 DIDescriptor Entity = resolve(Module.getEntity());
708 if (Entity.isNameSpace())
709 EntityDie = TheCU.getOrCreateNameSpace(DINameSpace(Entity));
710 else if (Entity.isSubprogram())
711 EntityDie = TheCU.getOrCreateSubprogramDIE(DISubprogram(Entity));
712 else if (Entity.isType())
713 EntityDie = TheCU.getOrCreateTypeDIE(DIType(Entity));
715 EntityDie = TheCU.getDIE(Entity);
716 TheCU.addSourceLine(IMDie, Module.getLineNumber(),
717 Module.getContext().getFilename(),
718 Module.getContext().getDirectory());
719 TheCU.addDIEEntry(IMDie, dwarf::DW_AT_import, *EntityDie);
720 StringRef Name = Module.getName();
722 TheCU.addString(IMDie, dwarf::DW_AT_name, Name);
725 // Emit all Dwarf sections that should come prior to the content. Create
726 // global DIEs and emit initial debug info sections. This is invoked by
727 // the target AsmPrinter.
728 void DwarfDebug::beginModule() {
729 if (DisableDebugInfoPrinting)
732 const Module *M = MMI->getModule();
734 // If module has named metadata anchors then use them, otherwise scan the
735 // module using debug info finder to collect debug info.
736 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
739 TypeIdentifierMap = generateDITypeIdentifierMap(CU_Nodes);
741 // Emit initial sections so we can reference labels later.
744 SingleCU = CU_Nodes->getNumOperands() == 1;
746 for (MDNode *N : CU_Nodes->operands()) {
747 DICompileUnit CUNode(N);
748 DwarfCompileUnit &CU = constructDwarfCompileUnit(CUNode);
749 DIArray ImportedEntities = CUNode.getImportedEntities();
750 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
751 ScopesWithImportedEntities.push_back(std::make_pair(
752 DIImportedEntity(ImportedEntities.getElement(i)).getContext(),
753 ImportedEntities.getElement(i)));
754 std::sort(ScopesWithImportedEntities.begin(),
755 ScopesWithImportedEntities.end(), less_first());
756 DIArray GVs = CUNode.getGlobalVariables();
757 for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i)
758 CU.createGlobalVariableDIE(DIGlobalVariable(GVs.getElement(i)));
759 DIArray SPs = CUNode.getSubprograms();
760 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i)
761 SPMap.insert(std::make_pair(SPs.getElement(i), &CU));
762 DIArray EnumTypes = CUNode.getEnumTypes();
763 for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i)
764 CU.getOrCreateTypeDIE(EnumTypes.getElement(i));
765 DIArray RetainedTypes = CUNode.getRetainedTypes();
766 for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i) {
767 DIType Ty(RetainedTypes.getElement(i));
768 // The retained types array by design contains pointers to
769 // MDNodes rather than DIRefs. Unique them here.
770 DIType UniqueTy(resolve(Ty.getRef()));
771 CU.getOrCreateTypeDIE(UniqueTy);
773 // Emit imported_modules last so that the relevant context is already
775 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
776 constructImportedEntityDIE(CU, ImportedEntities.getElement(i));
779 // Tell MMI that we have debug info.
780 MMI->setDebugInfoAvailability(true);
782 // Prime section data.
783 SectionMap[Asm->getObjFileLowering().getTextSection()];
786 void DwarfDebug::finishVariableDefinitions() {
787 for (const auto &Var : ConcreteVariables) {
788 DIE *VariableDie = Var->getDIE();
789 // FIXME: There shouldn't be any variables without DIEs.
792 // FIXME: Consider the time-space tradeoff of just storing the unit pointer
793 // in the ConcreteVariables list, rather than looking it up again here.
794 // DIE::getUnit isn't simple - it walks parent pointers, etc.
795 DwarfCompileUnit *Unit = lookupUnit(VariableDie->getUnit());
797 DbgVariable *AbsVar = getExistingAbstractVariable(Var->getVariable());
798 if (AbsVar && AbsVar->getDIE()) {
799 Unit->addDIEEntry(*VariableDie, dwarf::DW_AT_abstract_origin,
802 Unit->applyVariableAttributes(*Var, *VariableDie);
806 void DwarfDebug::finishSubprogramDefinitions() {
807 const Module *M = MMI->getModule();
809 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
810 for (MDNode *N : CU_Nodes->operands()) {
811 DICompileUnit TheCU(N);
812 // Construct subprogram DIE and add variables DIEs.
813 DwarfCompileUnit *SPCU =
814 static_cast<DwarfCompileUnit *>(CUMap.lookup(TheCU));
815 DIArray Subprograms = TheCU.getSubprograms();
816 for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) {
817 DISubprogram SP(Subprograms.getElement(i));
818 // Perhaps the subprogram is in another CU (such as due to comdat
819 // folding, etc), in which case ignore it here.
820 if (SPMap[SP] != SPCU)
822 DIE *D = SPCU->getDIE(SP);
823 if (DIE *AbsSPDIE = AbstractSPDies.lookup(SP)) {
825 // If this subprogram has an abstract definition, reference that
826 SPCU->addDIEEntry(*D, dwarf::DW_AT_abstract_origin, *AbsSPDIE);
829 // Lazily construct the subprogram if we didn't see either concrete or
830 // inlined versions during codegen.
831 D = SPCU->getOrCreateSubprogramDIE(SP);
832 // And attach the attributes
833 SPCU->applySubprogramAttributesToDefinition(SP, *D);
840 // Collect info for variables that were optimized out.
841 void DwarfDebug::collectDeadVariables() {
842 const Module *M = MMI->getModule();
844 if (NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu")) {
845 for (MDNode *N : CU_Nodes->operands()) {
846 DICompileUnit TheCU(N);
847 // Construct subprogram DIE and add variables DIEs.
848 DwarfCompileUnit *SPCU =
849 static_cast<DwarfCompileUnit *>(CUMap.lookup(TheCU));
850 assert(SPCU && "Unable to find Compile Unit!");
851 DIArray Subprograms = TheCU.getSubprograms();
852 for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) {
853 DISubprogram SP(Subprograms.getElement(i));
854 if (ProcessedSPNodes.count(SP) != 0)
856 assert(SP.isSubprogram() &&
857 "CU's subprogram list contains a non-subprogram");
858 assert(SP.isDefinition() &&
859 "CU's subprogram list contains a subprogram declaration");
860 DIArray Variables = SP.getVariables();
861 if (Variables.getNumElements() == 0)
864 DIE *SPDIE = AbstractSPDies.lookup(SP);
866 SPDIE = SPCU->getDIE(SP);
868 for (unsigned vi = 0, ve = Variables.getNumElements(); vi != ve; ++vi) {
869 DIVariable DV(Variables.getElement(vi));
870 assert(DV.isVariable());
871 DbgVariable NewVar(DV, this);
872 auto VariableDie = SPCU->constructVariableDIE(NewVar);
873 SPCU->applyVariableAttributes(NewVar, *VariableDie);
874 SPDIE->addChild(std::move(VariableDie));
881 void DwarfDebug::finalizeModuleInfo() {
882 finishSubprogramDefinitions();
884 finishVariableDefinitions();
886 // Collect info for variables that were optimized out.
887 collectDeadVariables();
889 // Handle anything that needs to be done on a per-unit basis after
890 // all other generation.
891 for (const auto &TheU : getUnits()) {
892 // Emit DW_AT_containing_type attribute to connect types with their
893 // vtable holding type.
894 TheU->constructContainingTypeDIEs();
896 // Add CU specific attributes if we need to add any.
897 if (TheU->getUnitDie().getTag() == dwarf::DW_TAG_compile_unit) {
898 // If we're splitting the dwarf out now that we've got the entire
899 // CU then add the dwo id to it.
900 DwarfCompileUnit *SkCU =
901 static_cast<DwarfCompileUnit *>(TheU->getSkeleton());
902 if (useSplitDwarf()) {
903 // Emit a unique identifier for this CU.
904 uint64_t ID = DIEHash(Asm).computeCUSignature(TheU->getUnitDie());
905 TheU->addUInt(TheU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
906 dwarf::DW_FORM_data8, ID);
907 SkCU->addUInt(SkCU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
908 dwarf::DW_FORM_data8, ID);
910 // We don't keep track of which addresses are used in which CU so this
911 // is a bit pessimistic under LTO.
912 if (!AddrPool.isEmpty())
913 addSectionLabel(*Asm, *SkCU, SkCU->getUnitDie(),
914 dwarf::DW_AT_GNU_addr_base, DwarfAddrSectionSym,
915 DwarfAddrSectionSym);
916 if (!TheU->getRangeLists().empty())
917 addSectionLabel(*Asm, *SkCU, SkCU->getUnitDie(),
918 dwarf::DW_AT_GNU_ranges_base,
919 DwarfDebugRangeSectionSym, DwarfDebugRangeSectionSym);
922 // If we have code split among multiple sections or non-contiguous
923 // ranges of code then emit a DW_AT_ranges attribute on the unit that will
924 // remain in the .o file, otherwise add a DW_AT_low_pc.
925 // FIXME: We should use ranges allow reordering of code ala
926 // .subsections_via_symbols in mach-o. This would mean turning on
927 // ranges for all subprogram DIEs for mach-o.
928 DwarfCompileUnit &U =
929 SkCU ? *SkCU : static_cast<DwarfCompileUnit &>(*TheU);
930 unsigned NumRanges = TheU->getRanges().size();
933 addSectionLabel(*Asm, U, U.getUnitDie(), dwarf::DW_AT_ranges,
934 Asm->GetTempSymbol("cu_ranges", U.getUniqueID()),
935 DwarfDebugRangeSectionSym);
937 // A DW_AT_low_pc attribute may also be specified in combination with
938 // DW_AT_ranges to specify the default base address for use in
939 // location lists (see Section 2.6.2) and range lists (see Section
941 U.addUInt(U.getUnitDie(), dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr,
944 RangeSpan &Range = TheU->getRanges().back();
945 U.addLocalLabelAddress(U.getUnitDie(), dwarf::DW_AT_low_pc,
947 U.addLabelDelta(U.getUnitDie(), dwarf::DW_AT_high_pc, Range.getEnd(),
954 // Compute DIE offsets and sizes.
955 InfoHolder.computeSizeAndOffsets();
957 SkeletonHolder.computeSizeAndOffsets();
960 void DwarfDebug::endSections() {
961 // Filter labels by section.
962 for (const SymbolCU &SCU : ArangeLabels) {
963 if (SCU.Sym->isInSection()) {
964 // Make a note of this symbol and it's section.
965 const MCSection *Section = &SCU.Sym->getSection();
966 if (!Section->getKind().isMetadata())
967 SectionMap[Section].push_back(SCU);
969 // Some symbols (e.g. common/bss on mach-o) can have no section but still
970 // appear in the output. This sucks as we rely on sections to build
971 // arange spans. We can do it without, but it's icky.
972 SectionMap[nullptr].push_back(SCU);
976 // Build a list of sections used.
977 std::vector<const MCSection *> Sections;
978 for (const auto &it : SectionMap) {
979 const MCSection *Section = it.first;
980 Sections.push_back(Section);
983 // Sort the sections into order.
984 // This is only done to ensure consistent output order across different runs.
985 std::sort(Sections.begin(), Sections.end(), SectionSort);
987 // Add terminating symbols for each section.
988 for (unsigned ID = 0, E = Sections.size(); ID != E; ID++) {
989 const MCSection *Section = Sections[ID];
990 MCSymbol *Sym = nullptr;
993 // We can't call MCSection::getLabelEndName, as it's only safe to do so
994 // if we know the section name up-front. For user-created sections, the
995 // resulting label may not be valid to use as a label. (section names can
996 // use a greater set of characters on some systems)
997 Sym = Asm->GetTempSymbol("debug_end", ID);
998 Asm->OutStreamer.SwitchSection(Section);
999 Asm->OutStreamer.EmitLabel(Sym);
1002 // Insert a final terminator.
1003 SectionMap[Section].push_back(SymbolCU(nullptr, Sym));
1007 // Emit all Dwarf sections that should come after the content.
1008 void DwarfDebug::endModule() {
1009 assert(CurFn == nullptr);
1010 assert(CurMI == nullptr);
1015 // End any existing sections.
1016 // TODO: Does this need to happen?
1019 // Finalize the debug info for the module.
1020 finalizeModuleInfo();
1024 // Emit all the DIEs into a debug info section.
1027 // Corresponding abbreviations into a abbrev section.
1028 emitAbbreviations();
1030 // Emit info into a debug aranges section.
1031 if (GenerateARangeSection)
1034 // Emit info into a debug ranges section.
1037 if (useSplitDwarf()) {
1040 emitDebugAbbrevDWO();
1042 // Emit DWO addresses.
1043 AddrPool.emit(*Asm, Asm->getObjFileLowering().getDwarfAddrSection());
1046 // Emit info into a debug loc section.
1049 // Emit info into the dwarf accelerator table sections.
1050 if (useDwarfAccelTables()) {
1053 emitAccelNamespaces();
1057 // Emit the pubnames and pubtypes sections if requested.
1058 if (HasDwarfPubSections) {
1059 emitDebugPubNames(GenerateGnuPubSections);
1060 emitDebugPubTypes(GenerateGnuPubSections);
1065 AbstractVariables.clear();
1067 // Reset these for the next Module if we have one.
1071 // Find abstract variable, if any, associated with Var.
1072 DbgVariable *DwarfDebug::getExistingAbstractVariable(const DIVariable &DV,
1073 DIVariable &Cleansed) {
1074 LLVMContext &Ctx = DV->getContext();
1075 // More then one inlined variable corresponds to one abstract variable.
1076 // FIXME: This duplication of variables when inlining should probably be
1077 // removed. It's done to allow each DIVariable to describe its location
1078 // because the DebugLoc on the dbg.value/declare isn't accurate. We should
1079 // make it accurate then remove this duplication/cleansing stuff.
1080 Cleansed = cleanseInlinedVariable(DV, Ctx);
1081 auto I = AbstractVariables.find(Cleansed);
1082 if (I != AbstractVariables.end())
1083 return I->second.get();
1087 DbgVariable *DwarfDebug::getExistingAbstractVariable(const DIVariable &DV) {
1088 DIVariable Cleansed;
1089 return getExistingAbstractVariable(DV, Cleansed);
1092 void DwarfDebug::createAbstractVariable(const DIVariable &Var,
1093 LexicalScope *Scope) {
1094 auto AbsDbgVariable = make_unique<DbgVariable>(Var, this);
1095 addScopeVariable(Scope, AbsDbgVariable.get());
1096 AbstractVariables[Var] = std::move(AbsDbgVariable);
1099 void DwarfDebug::ensureAbstractVariableIsCreated(const DIVariable &DV,
1100 const MDNode *ScopeNode) {
1101 DIVariable Cleansed = DV;
1102 if (getExistingAbstractVariable(DV, Cleansed))
1105 createAbstractVariable(Cleansed, LScopes.getOrCreateAbstractScope(ScopeNode));
1109 DwarfDebug::ensureAbstractVariableIsCreatedIfScoped(const DIVariable &DV,
1110 const MDNode *ScopeNode) {
1111 DIVariable Cleansed = DV;
1112 if (getExistingAbstractVariable(DV, Cleansed))
1115 if (LexicalScope *Scope = LScopes.findAbstractScope(ScopeNode))
1116 createAbstractVariable(Cleansed, Scope);
1119 // If Var is a current function argument then add it to CurrentFnArguments list.
1120 bool DwarfDebug::addCurrentFnArgument(DbgVariable *Var, LexicalScope *Scope) {
1121 if (!LScopes.isCurrentFunctionScope(Scope))
1123 DIVariable DV = Var->getVariable();
1124 if (DV.getTag() != dwarf::DW_TAG_arg_variable)
1126 unsigned ArgNo = DV.getArgNumber();
1130 size_t Size = CurrentFnArguments.size();
1132 CurrentFnArguments.resize(CurFn->getFunction()->arg_size());
1133 // llvm::Function argument size is not good indicator of how many
1134 // arguments does the function have at source level.
1136 CurrentFnArguments.resize(ArgNo * 2);
1137 CurrentFnArguments[ArgNo - 1] = Var;
1141 // Collect variable information from side table maintained by MMI.
1142 void DwarfDebug::collectVariableInfoFromMMITable(
1143 SmallPtrSet<const MDNode *, 16> &Processed) {
1144 for (const auto &VI : MMI->getVariableDbgInfo()) {
1147 Processed.insert(VI.Var);
1148 DIVariable DV(VI.Var);
1149 LexicalScope *Scope = LScopes.findLexicalScope(VI.Loc);
1151 // If variable scope is not found then skip this variable.
1155 ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode());
1156 ConcreteVariables.push_back(make_unique<DbgVariable>(DV, this));
1157 DbgVariable *RegVar = ConcreteVariables.back().get();
1158 RegVar->setFrameIndex(VI.Slot);
1159 addScopeVariable(Scope, RegVar);
1163 // Get .debug_loc entry for the instruction range starting at MI.
1164 static DebugLocEntry::Value getDebugLocValue(const MachineInstr *MI) {
1165 const MDNode *Var = MI->getDebugVariable();
1167 assert(MI->getNumOperands() == 3);
1168 if (MI->getOperand(0).isReg()) {
1169 MachineLocation MLoc;
1170 // If the second operand is an immediate, this is a
1171 // register-indirect address.
1172 if (!MI->getOperand(1).isImm())
1173 MLoc.set(MI->getOperand(0).getReg());
1175 MLoc.set(MI->getOperand(0).getReg(), MI->getOperand(1).getImm());
1176 return DebugLocEntry::Value(Var, MLoc);
1178 if (MI->getOperand(0).isImm())
1179 return DebugLocEntry::Value(Var, MI->getOperand(0).getImm());
1180 if (MI->getOperand(0).isFPImm())
1181 return DebugLocEntry::Value(Var, MI->getOperand(0).getFPImm());
1182 if (MI->getOperand(0).isCImm())
1183 return DebugLocEntry::Value(Var, MI->getOperand(0).getCImm());
1185 llvm_unreachable("Unexpected 3 operand DBG_VALUE instruction!");
1188 // Find variables for each lexical scope.
1190 DwarfDebug::collectVariableInfo(SmallPtrSet<const MDNode *, 16> &Processed) {
1191 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1192 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1194 // Grab the variable info that was squirreled away in the MMI side-table.
1195 collectVariableInfoFromMMITable(Processed);
1197 for (const auto &I : DbgValues) {
1198 DIVariable DV(I.first);
1199 if (Processed.count(DV))
1202 // Instruction ranges, specifying where DV is accessible.
1203 const auto &Ranges = I.second;
1207 LexicalScope *Scope = nullptr;
1208 if (DV.getTag() == dwarf::DW_TAG_arg_variable &&
1209 DISubprogram(DV.getContext()).describes(CurFn->getFunction()))
1210 Scope = LScopes.getCurrentFunctionScope();
1211 else if (MDNode *IA = DV.getInlinedAt()) {
1212 DebugLoc DL = DebugLoc::getFromDILocation(IA);
1213 Scope = LScopes.findInlinedScope(DebugLoc::get(
1214 DL.getLine(), DL.getCol(), DV.getContext(), IA));
1216 Scope = LScopes.findLexicalScope(DV.getContext());
1217 // If variable scope is not found then skip this variable.
1221 Processed.insert(DV);
1222 const MachineInstr *MInsn = Ranges.front().first;
1223 assert(MInsn->isDebugValue() && "History must begin with debug value");
1224 ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode());
1225 ConcreteVariables.push_back(make_unique<DbgVariable>(MInsn, this));
1226 DbgVariable *RegVar = ConcreteVariables.back().get();
1227 addScopeVariable(Scope, RegVar);
1229 // Check if the first DBG_VALUE is valid for the rest of the function.
1230 if (Ranges.size() == 1 && Ranges.front().second == nullptr)
1233 // Handle multiple DBG_VALUE instructions describing one variable.
1234 RegVar->setDotDebugLocOffset(DotDebugLocEntries.size());
1236 DotDebugLocEntries.resize(DotDebugLocEntries.size() + 1);
1237 DebugLocList &LocList = DotDebugLocEntries.back();
1239 Asm->GetTempSymbol("debug_loc", DotDebugLocEntries.size() - 1);
1240 SmallVector<DebugLocEntry, 4> &DebugLoc = LocList.List;
1241 for (auto I = Ranges.begin(), E = Ranges.end(); I != E; ++I) {
1242 const MachineInstr *Begin = I->first;
1243 const MachineInstr *End = I->second;
1244 assert(Begin->isDebugValue() && "Invalid History entry");
1246 // Check if a variable is unaccessible in this range.
1247 if (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() &&
1248 !Begin->getOperand(0).getReg())
1250 DEBUG(dbgs() << "DotDebugLoc Pair:\n" << "\t" << *Begin);
1252 DEBUG(dbgs() << "\t" << *End);
1254 DEBUG(dbgs() << "\tNULL\n");
1256 const MCSymbol *StartLabel = getLabelBeforeInsn(Begin);
1257 assert(StartLabel && "Forgot label before DBG_VALUE starting a range!");
1259 const MCSymbol *EndLabel;
1261 EndLabel = getLabelAfterInsn(End);
1262 else if (std::next(I) == Ranges.end())
1263 EndLabel = FunctionEndSym;
1265 EndLabel = getLabelBeforeInsn(std::next(I)->first);
1266 assert(EndLabel && "Forgot label after instruction ending a range!");
1268 DebugLocEntry Loc(StartLabel, EndLabel, getDebugLocValue(Begin), TheCU);
1269 if (DebugLoc.empty() || !DebugLoc.back().Merge(Loc))
1270 DebugLoc.push_back(std::move(Loc));
1274 // Collect info for variables that were optimized out.
1275 DIArray Variables = DISubprogram(FnScope->getScopeNode()).getVariables();
1276 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1277 DIVariable DV(Variables.getElement(i));
1278 assert(DV.isVariable());
1279 if (!Processed.insert(DV))
1281 if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext())) {
1282 ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode());
1283 ConcreteVariables.push_back(make_unique<DbgVariable>(DV, this));
1284 addScopeVariable(Scope, ConcreteVariables.back().get());
1289 // Return Label preceding the instruction.
1290 MCSymbol *DwarfDebug::getLabelBeforeInsn(const MachineInstr *MI) {
1291 MCSymbol *Label = LabelsBeforeInsn.lookup(MI);
1292 assert(Label && "Didn't insert label before instruction");
1296 // Return Label immediately following the instruction.
1297 MCSymbol *DwarfDebug::getLabelAfterInsn(const MachineInstr *MI) {
1298 return LabelsAfterInsn.lookup(MI);
1301 // Process beginning of an instruction.
1302 void DwarfDebug::beginInstruction(const MachineInstr *MI) {
1303 assert(CurMI == nullptr);
1305 // Check if source location changes, but ignore DBG_VALUE locations.
1306 if (!MI->isDebugValue()) {
1307 DebugLoc DL = MI->getDebugLoc();
1308 if (DL != PrevInstLoc && (!DL.isUnknown() || UnknownLocations)) {
1311 if (DL == PrologEndLoc) {
1312 Flags |= DWARF2_FLAG_PROLOGUE_END;
1313 PrologEndLoc = DebugLoc();
1315 if (PrologEndLoc.isUnknown())
1316 Flags |= DWARF2_FLAG_IS_STMT;
1318 if (!DL.isUnknown()) {
1319 const MDNode *Scope = DL.getScope(Asm->MF->getFunction()->getContext());
1320 recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags);
1322 recordSourceLine(0, 0, nullptr, 0);
1326 // Insert labels where requested.
1327 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1328 LabelsBeforeInsn.find(MI);
1331 if (I == LabelsBeforeInsn.end())
1334 // Label already assigned.
1339 PrevLabel = MMI->getContext().CreateTempSymbol();
1340 Asm->OutStreamer.EmitLabel(PrevLabel);
1342 I->second = PrevLabel;
1345 // Process end of an instruction.
1346 void DwarfDebug::endInstruction() {
1347 assert(CurMI != nullptr);
1348 // Don't create a new label after DBG_VALUE instructions.
1349 // They don't generate code.
1350 if (!CurMI->isDebugValue())
1351 PrevLabel = nullptr;
1353 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1354 LabelsAfterInsn.find(CurMI);
1358 if (I == LabelsAfterInsn.end())
1361 // Label already assigned.
1365 // We need a label after this instruction.
1367 PrevLabel = MMI->getContext().CreateTempSymbol();
1368 Asm->OutStreamer.EmitLabel(PrevLabel);
1370 I->second = PrevLabel;
1373 // Each LexicalScope has first instruction and last instruction to mark
1374 // beginning and end of a scope respectively. Create an inverse map that list
1375 // scopes starts (and ends) with an instruction. One instruction may start (or
1376 // end) multiple scopes. Ignore scopes that are not reachable.
1377 void DwarfDebug::identifyScopeMarkers() {
1378 SmallVector<LexicalScope *, 4> WorkList;
1379 WorkList.push_back(LScopes.getCurrentFunctionScope());
1380 while (!WorkList.empty()) {
1381 LexicalScope *S = WorkList.pop_back_val();
1383 const SmallVectorImpl<LexicalScope *> &Children = S->getChildren();
1384 if (!Children.empty())
1385 WorkList.append(Children.begin(), Children.end());
1387 if (S->isAbstractScope())
1390 for (const InsnRange &R : S->getRanges()) {
1391 assert(R.first && "InsnRange does not have first instruction!");
1392 assert(R.second && "InsnRange does not have second instruction!");
1393 requestLabelBeforeInsn(R.first);
1394 requestLabelAfterInsn(R.second);
1399 static DebugLoc findPrologueEndLoc(const MachineFunction *MF) {
1400 // First known non-DBG_VALUE and non-frame setup location marks
1401 // the beginning of the function body.
1402 for (const auto &MBB : *MF)
1403 for (const auto &MI : MBB)
1404 if (!MI.isDebugValue() && !MI.getFlag(MachineInstr::FrameSetup) &&
1405 !MI.getDebugLoc().isUnknown())
1406 return MI.getDebugLoc();
1410 // Gather pre-function debug information. Assumes being called immediately
1411 // after the function entry point has been emitted.
1412 void DwarfDebug::beginFunction(const MachineFunction *MF) {
1415 // If there's no debug info for the function we're not going to do anything.
1416 if (!MMI->hasDebugInfo())
1419 // Grab the lexical scopes for the function, if we don't have any of those
1420 // then we're not going to be able to do anything.
1421 LScopes.initialize(*MF);
1422 if (LScopes.empty())
1425 assert(DbgValues.empty() && "DbgValues map wasn't cleaned!");
1427 // Make sure that each lexical scope will have a begin/end label.
1428 identifyScopeMarkers();
1430 // Set DwarfDwarfCompileUnitID in MCContext to the Compile Unit this function
1431 // belongs to so that we add to the correct per-cu line table in the
1433 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1434 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1435 assert(TheCU && "Unable to find compile unit!");
1436 if (Asm->OutStreamer.hasRawTextSupport())
1437 // Use a single line table if we are generating assembly.
1438 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1440 Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID());
1442 // Emit a label for the function so that we have a beginning address.
1443 FunctionBeginSym = Asm->GetTempSymbol("func_begin", Asm->getFunctionNumber());
1444 // Assumes in correct section after the entry point.
1445 Asm->OutStreamer.EmitLabel(FunctionBeginSym);
1447 // Calculate history for local variables.
1448 calculateDbgValueHistory(MF, Asm->TM.getRegisterInfo(), DbgValues);
1450 // Request labels for the full history.
1451 for (const auto &I : DbgValues) {
1452 const auto &Ranges = I.second;
1456 // The first mention of a function argument gets the FunctionBeginSym
1457 // label, so arguments are visible when breaking at function entry.
1458 DIVariable DV(I.first);
1459 if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable &&
1460 getDISubprogram(DV.getContext()).describes(MF->getFunction()))
1461 LabelsBeforeInsn[Ranges.front().first] = FunctionBeginSym;
1463 for (const auto &Range : Ranges) {
1464 requestLabelBeforeInsn(Range.first);
1466 requestLabelAfterInsn(Range.second);
1470 PrevInstLoc = DebugLoc();
1471 PrevLabel = FunctionBeginSym;
1473 // Record beginning of function.
1474 PrologEndLoc = findPrologueEndLoc(MF);
1475 if (!PrologEndLoc.isUnknown()) {
1476 DebugLoc FnStartDL =
1477 PrologEndLoc.getFnDebugLoc(MF->getFunction()->getContext());
1479 FnStartDL.getLine(), FnStartDL.getCol(),
1480 FnStartDL.getScope(MF->getFunction()->getContext()),
1481 // We'd like to list the prologue as "not statements" but GDB behaves
1482 // poorly if we do that. Revisit this with caution/GDB (7.5+) testing.
1483 DWARF2_FLAG_IS_STMT);
1487 void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) {
1488 if (addCurrentFnArgument(Var, LS))
1490 SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS];
1491 DIVariable DV = Var->getVariable();
1492 // Variables with positive arg numbers are parameters.
1493 if (unsigned ArgNum = DV.getArgNumber()) {
1494 // Keep all parameters in order at the start of the variable list to ensure
1495 // function types are correct (no out-of-order parameters)
1497 // This could be improved by only doing it for optimized builds (unoptimized
1498 // builds have the right order to begin with), searching from the back (this
1499 // would catch the unoptimized case quickly), or doing a binary search
1500 // rather than linear search.
1501 SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin();
1502 while (I != Vars.end()) {
1503 unsigned CurNum = (*I)->getVariable().getArgNumber();
1504 // A local (non-parameter) variable has been found, insert immediately
1508 // A later indexed parameter has been found, insert immediately before it.
1509 if (CurNum > ArgNum)
1513 Vars.insert(I, Var);
1517 Vars.push_back(Var);
1520 // Gather and emit post-function debug information.
1521 void DwarfDebug::endFunction(const MachineFunction *MF) {
1522 // Every beginFunction(MF) call should be followed by an endFunction(MF) call,
1523 // though the beginFunction may not be called at all.
1524 // We should handle both cases.
1528 assert(CurFn == MF);
1529 assert(CurFn != nullptr);
1531 if (!MMI->hasDebugInfo() || LScopes.empty()) {
1532 // If we don't have a lexical scope for this function then there will
1533 // be a hole in the range information. Keep note of this by setting the
1534 // previously used section to nullptr.
1535 PrevSection = nullptr;
1541 // Define end label for subprogram.
1542 FunctionEndSym = Asm->GetTempSymbol("func_end", Asm->getFunctionNumber());
1543 // Assumes in correct section after the entry point.
1544 Asm->OutStreamer.EmitLabel(FunctionEndSym);
1546 // Set DwarfDwarfCompileUnitID in MCContext to default value.
1547 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1549 SmallPtrSet<const MDNode *, 16> ProcessedVars;
1550 collectVariableInfo(ProcessedVars);
1552 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1553 DwarfCompileUnit &TheCU = *SPMap.lookup(FnScope->getScopeNode());
1555 // Construct abstract scopes.
1556 for (LexicalScope *AScope : LScopes.getAbstractScopesList()) {
1557 DISubprogram SP(AScope->getScopeNode());
1558 if (!SP.isSubprogram())
1560 // Collect info for variables that were optimized out.
1561 DIArray Variables = SP.getVariables();
1562 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1563 DIVariable DV(Variables.getElement(i));
1564 assert(DV && DV.isVariable());
1565 if (!ProcessedVars.insert(DV))
1567 ensureAbstractVariableIsCreated(DV, DV.getContext());
1569 constructAbstractSubprogramScopeDIE(TheCU, AScope);
1572 DIE &CurFnDIE = constructSubprogramScopeDIE(TheCU, FnScope);
1573 if (!CurFn->getTarget().Options.DisableFramePointerElim(*CurFn))
1574 TheCU.addFlag(CurFnDIE, dwarf::DW_AT_APPLE_omit_frame_ptr);
1576 // Add the range of this function to the list of ranges for the CU.
1577 RangeSpan Span(FunctionBeginSym, FunctionEndSym);
1578 TheCU.addRange(std::move(Span));
1579 PrevSection = Asm->getCurrentSection();
1583 // Ownership of DbgVariables is a bit subtle - ScopeVariables owns all the
1584 // DbgVariables except those that are also in AbstractVariables (since they
1585 // can be used cross-function)
1586 ScopeVariables.clear();
1587 CurrentFnArguments.clear();
1589 LabelsBeforeInsn.clear();
1590 LabelsAfterInsn.clear();
1591 PrevLabel = nullptr;
1595 // Register a source line with debug info. Returns the unique label that was
1596 // emitted and which provides correspondence to the source line list.
1597 void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S,
1602 unsigned Discriminator = 0;
1603 if (DIScope Scope = DIScope(S)) {
1604 assert(Scope.isScope());
1605 Fn = Scope.getFilename();
1606 Dir = Scope.getDirectory();
1607 if (Scope.isLexicalBlock())
1608 Discriminator = DILexicalBlock(S).getDiscriminator();
1610 unsigned CUID = Asm->OutStreamer.getContext().getDwarfCompileUnitID();
1611 Src = static_cast<DwarfCompileUnit &>(*InfoHolder.getUnits()[CUID])
1612 .getOrCreateSourceID(Fn, Dir);
1614 Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0,
1618 //===----------------------------------------------------------------------===//
1620 //===----------------------------------------------------------------------===//
1622 // Emit initial Dwarf sections with a label at the start of each one.
1623 void DwarfDebug::emitSectionLabels() {
1624 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
1626 // Dwarf sections base addresses.
1627 DwarfInfoSectionSym =
1628 emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info");
1629 if (useSplitDwarf())
1630 DwarfInfoDWOSectionSym =
1631 emitSectionSym(Asm, TLOF.getDwarfInfoDWOSection(), "section_info_dwo");
1632 DwarfAbbrevSectionSym =
1633 emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev");
1634 if (useSplitDwarf())
1635 DwarfAbbrevDWOSectionSym = emitSectionSym(
1636 Asm, TLOF.getDwarfAbbrevDWOSection(), "section_abbrev_dwo");
1637 if (GenerateARangeSection)
1638 emitSectionSym(Asm, TLOF.getDwarfARangesSection());
1640 DwarfLineSectionSym =
1641 emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line");
1642 if (GenerateGnuPubSections) {
1643 DwarfGnuPubNamesSectionSym =
1644 emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection());
1645 DwarfGnuPubTypesSectionSym =
1646 emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection());
1647 } else if (HasDwarfPubSections) {
1648 emitSectionSym(Asm, TLOF.getDwarfPubNamesSection());
1649 emitSectionSym(Asm, TLOF.getDwarfPubTypesSection());
1652 DwarfStrSectionSym =
1653 emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string");
1654 if (useSplitDwarf()) {
1655 DwarfStrDWOSectionSym =
1656 emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string");
1657 DwarfAddrSectionSym =
1658 emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec");
1659 DwarfDebugLocSectionSym =
1660 emitSectionSym(Asm, TLOF.getDwarfLocDWOSection(), "skel_loc");
1662 DwarfDebugLocSectionSym =
1663 emitSectionSym(Asm, TLOF.getDwarfLocSection(), "section_debug_loc");
1664 DwarfDebugRangeSectionSym =
1665 emitSectionSym(Asm, TLOF.getDwarfRangesSection(), "debug_range");
1668 // Recursively emits a debug information entry.
1669 void DwarfDebug::emitDIE(DIE &Die) {
1670 // Get the abbreviation for this DIE.
1671 const DIEAbbrev &Abbrev = Die.getAbbrev();
1673 // Emit the code (index) for the abbreviation.
1674 if (Asm->isVerbose())
1675 Asm->OutStreamer.AddComment("Abbrev [" + Twine(Abbrev.getNumber()) +
1676 "] 0x" + Twine::utohexstr(Die.getOffset()) +
1677 ":0x" + Twine::utohexstr(Die.getSize()) + " " +
1678 dwarf::TagString(Abbrev.getTag()));
1679 Asm->EmitULEB128(Abbrev.getNumber());
1681 const SmallVectorImpl<DIEValue *> &Values = Die.getValues();
1682 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
1684 // Emit the DIE attribute values.
1685 for (unsigned i = 0, N = Values.size(); i < N; ++i) {
1686 dwarf::Attribute Attr = AbbrevData[i].getAttribute();
1687 dwarf::Form Form = AbbrevData[i].getForm();
1688 assert(Form && "Too many attributes for DIE (check abbreviation)");
1690 if (Asm->isVerbose()) {
1691 Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr));
1692 if (Attr == dwarf::DW_AT_accessibility)
1693 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(
1694 cast<DIEInteger>(Values[i])->getValue()));
1697 // Emit an attribute using the defined form.
1698 Values[i]->EmitValue(Asm, Form);
1701 // Emit the DIE children if any.
1702 if (Abbrev.hasChildren()) {
1703 for (auto &Child : Die.getChildren())
1706 Asm->OutStreamer.AddComment("End Of Children Mark");
1711 // Emit the debug info section.
1712 void DwarfDebug::emitDebugInfo() {
1713 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1715 Holder.emitUnits(this, DwarfAbbrevSectionSym);
1718 // Emit the abbreviation section.
1719 void DwarfDebug::emitAbbreviations() {
1720 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1722 Holder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection());
1725 // Emit the last address of the section and the end of the line matrix.
1726 void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) {
1727 // Define last address of section.
1728 Asm->OutStreamer.AddComment("Extended Op");
1731 Asm->OutStreamer.AddComment("Op size");
1732 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1);
1733 Asm->OutStreamer.AddComment("DW_LNE_set_address");
1734 Asm->EmitInt8(dwarf::DW_LNE_set_address);
1736 Asm->OutStreamer.AddComment("Section end label");
1738 Asm->OutStreamer.EmitSymbolValue(
1739 Asm->GetTempSymbol("section_end", SectionEnd),
1740 Asm->getDataLayout().getPointerSize());
1742 // Mark end of matrix.
1743 Asm->OutStreamer.AddComment("DW_LNE_end_sequence");
1749 // Emit visible names into a hashed accelerator table section.
1750 void DwarfDebug::emitAccelNames() {
1751 AccelNames.FinalizeTable(Asm, "Names");
1752 Asm->OutStreamer.SwitchSection(
1753 Asm->getObjFileLowering().getDwarfAccelNamesSection());
1754 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin");
1755 Asm->OutStreamer.EmitLabel(SectionBegin);
1757 // Emit the full data.
1758 AccelNames.Emit(Asm, SectionBegin, &InfoHolder);
1761 // Emit objective C classes and categories into a hashed accelerator table
1763 void DwarfDebug::emitAccelObjC() {
1764 AccelObjC.FinalizeTable(Asm, "ObjC");
1765 Asm->OutStreamer.SwitchSection(
1766 Asm->getObjFileLowering().getDwarfAccelObjCSection());
1767 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin");
1768 Asm->OutStreamer.EmitLabel(SectionBegin);
1770 // Emit the full data.
1771 AccelObjC.Emit(Asm, SectionBegin, &InfoHolder);
1774 // Emit namespace dies into a hashed accelerator table.
1775 void DwarfDebug::emitAccelNamespaces() {
1776 AccelNamespace.FinalizeTable(Asm, "namespac");
1777 Asm->OutStreamer.SwitchSection(
1778 Asm->getObjFileLowering().getDwarfAccelNamespaceSection());
1779 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin");
1780 Asm->OutStreamer.EmitLabel(SectionBegin);
1782 // Emit the full data.
1783 AccelNamespace.Emit(Asm, SectionBegin, &InfoHolder);
1786 // Emit type dies into a hashed accelerator table.
1787 void DwarfDebug::emitAccelTypes() {
1789 AccelTypes.FinalizeTable(Asm, "types");
1790 Asm->OutStreamer.SwitchSection(
1791 Asm->getObjFileLowering().getDwarfAccelTypesSection());
1792 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin");
1793 Asm->OutStreamer.EmitLabel(SectionBegin);
1795 // Emit the full data.
1796 AccelTypes.Emit(Asm, SectionBegin, &InfoHolder);
1799 // Public name handling.
1800 // The format for the various pubnames:
1802 // dwarf pubnames - offset/name pairs where the offset is the offset into the CU
1803 // for the DIE that is named.
1805 // gnu pubnames - offset/index value/name tuples where the offset is the offset
1806 // into the CU and the index value is computed according to the type of value
1807 // for the DIE that is named.
1809 // For type units the offset is the offset of the skeleton DIE. For split dwarf
1810 // it's the offset within the debug_info/debug_types dwo section, however, the
1811 // reference in the pubname header doesn't change.
1813 /// computeIndexValue - Compute the gdb index value for the DIE and CU.
1814 static dwarf::PubIndexEntryDescriptor computeIndexValue(DwarfUnit *CU,
1816 dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC;
1818 // We could have a specification DIE that has our most of our knowledge,
1819 // look for that now.
1820 DIEValue *SpecVal = Die->findAttribute(dwarf::DW_AT_specification);
1822 DIE &SpecDIE = cast<DIEEntry>(SpecVal)->getEntry();
1823 if (SpecDIE.findAttribute(dwarf::DW_AT_external))
1824 Linkage = dwarf::GIEL_EXTERNAL;
1825 } else if (Die->findAttribute(dwarf::DW_AT_external))
1826 Linkage = dwarf::GIEL_EXTERNAL;
1828 switch (Die->getTag()) {
1829 case dwarf::DW_TAG_class_type:
1830 case dwarf::DW_TAG_structure_type:
1831 case dwarf::DW_TAG_union_type:
1832 case dwarf::DW_TAG_enumeration_type:
1833 return dwarf::PubIndexEntryDescriptor(
1834 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus
1835 ? dwarf::GIEL_STATIC
1836 : dwarf::GIEL_EXTERNAL);
1837 case dwarf::DW_TAG_typedef:
1838 case dwarf::DW_TAG_base_type:
1839 case dwarf::DW_TAG_subrange_type:
1840 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC);
1841 case dwarf::DW_TAG_namespace:
1842 return dwarf::GIEK_TYPE;
1843 case dwarf::DW_TAG_subprogram:
1844 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage);
1845 case dwarf::DW_TAG_constant:
1846 case dwarf::DW_TAG_variable:
1847 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage);
1848 case dwarf::DW_TAG_enumerator:
1849 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE,
1850 dwarf::GIEL_STATIC);
1852 return dwarf::GIEK_NONE;
1856 /// emitDebugPubNames - Emit visible names into a debug pubnames section.
1858 void DwarfDebug::emitDebugPubNames(bool GnuStyle) {
1859 const MCSection *PSec =
1860 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection()
1861 : Asm->getObjFileLowering().getDwarfPubNamesSection();
1863 emitDebugPubSection(GnuStyle, PSec, "Names", &DwarfUnit::getGlobalNames);
1866 void DwarfDebug::emitDebugPubSection(
1867 bool GnuStyle, const MCSection *PSec, StringRef Name,
1868 const StringMap<const DIE *> &(DwarfUnit::*Accessor)() const) {
1869 for (const auto &NU : CUMap) {
1870 DwarfCompileUnit *TheU = NU.second;
1872 const auto &Globals = (TheU->*Accessor)();
1874 if (Globals.empty())
1877 if (auto Skeleton = static_cast<DwarfCompileUnit *>(TheU->getSkeleton()))
1879 unsigned ID = TheU->getUniqueID();
1881 // Start the dwarf pubnames section.
1882 Asm->OutStreamer.SwitchSection(PSec);
1885 Asm->OutStreamer.AddComment("Length of Public " + Name + " Info");
1886 MCSymbol *BeginLabel = Asm->GetTempSymbol("pub" + Name + "_begin", ID);
1887 MCSymbol *EndLabel = Asm->GetTempSymbol("pub" + Name + "_end", ID);
1888 Asm->EmitLabelDifference(EndLabel, BeginLabel, 4);
1890 Asm->OutStreamer.EmitLabel(BeginLabel);
1892 Asm->OutStreamer.AddComment("DWARF Version");
1893 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION);
1895 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info");
1896 Asm->EmitSectionOffset(TheU->getLabelBegin(), TheU->getSectionSym());
1898 Asm->OutStreamer.AddComment("Compilation Unit Length");
1899 Asm->EmitLabelDifference(TheU->getLabelEnd(), TheU->getLabelBegin(), 4);
1901 // Emit the pubnames for this compilation unit.
1902 for (const auto &GI : Globals) {
1903 const char *Name = GI.getKeyData();
1904 const DIE *Entity = GI.second;
1906 Asm->OutStreamer.AddComment("DIE offset");
1907 Asm->EmitInt32(Entity->getOffset());
1910 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheU, Entity);
1911 Asm->OutStreamer.AddComment(
1912 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " +
1913 dwarf::GDBIndexEntryLinkageString(Desc.Linkage));
1914 Asm->EmitInt8(Desc.toBits());
1917 Asm->OutStreamer.AddComment("External Name");
1918 Asm->OutStreamer.EmitBytes(StringRef(Name, GI.getKeyLength() + 1));
1921 Asm->OutStreamer.AddComment("End Mark");
1923 Asm->OutStreamer.EmitLabel(EndLabel);
1927 void DwarfDebug::emitDebugPubTypes(bool GnuStyle) {
1928 const MCSection *PSec =
1929 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection()
1930 : Asm->getObjFileLowering().getDwarfPubTypesSection();
1932 emitDebugPubSection(GnuStyle, PSec, "Types", &DwarfUnit::getGlobalTypes);
1935 // Emit visible names into a debug str section.
1936 void DwarfDebug::emitDebugStr() {
1937 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1938 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection());
1941 void DwarfDebug::emitDebugLocEntry(ByteStreamer &Streamer,
1942 const DebugLocEntry &Entry) {
1943 assert(Entry.getValues().size() == 1 &&
1944 "multi-value entries are not supported yet.");
1945 const DebugLocEntry::Value Value = Entry.getValues()[0];
1946 DIVariable DV(Value.getVariable());
1947 if (Value.isInt()) {
1948 DIBasicType BTy(resolve(DV.getType()));
1949 if (BTy.Verify() && (BTy.getEncoding() == dwarf::DW_ATE_signed ||
1950 BTy.getEncoding() == dwarf::DW_ATE_signed_char)) {
1951 Streamer.EmitInt8(dwarf::DW_OP_consts, "DW_OP_consts");
1952 Streamer.EmitSLEB128(Value.getInt());
1954 Streamer.EmitInt8(dwarf::DW_OP_constu, "DW_OP_constu");
1955 Streamer.EmitULEB128(Value.getInt());
1957 } else if (Value.isLocation()) {
1958 MachineLocation Loc = Value.getLoc();
1959 if (!DV.hasComplexAddress())
1961 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
1963 // Complex address entry.
1964 unsigned N = DV.getNumAddrElements();
1966 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) {
1967 if (Loc.getOffset()) {
1969 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
1970 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
1971 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
1972 Streamer.EmitSLEB128(DV.getAddrElement(1));
1974 // If first address element is OpPlus then emit
1975 // DW_OP_breg + Offset instead of DW_OP_reg + Offset.
1976 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1));
1977 Asm->EmitDwarfRegOp(Streamer, TLoc, DV.isIndirect());
1981 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
1984 // Emit remaining complex address elements.
1985 for (; i < N; ++i) {
1986 uint64_t Element = DV.getAddrElement(i);
1987 if (Element == DIBuilder::OpPlus) {
1988 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
1989 Streamer.EmitULEB128(DV.getAddrElement(++i));
1990 } else if (Element == DIBuilder::OpDeref) {
1992 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
1994 llvm_unreachable("unknown Opcode found in complex address");
1998 // else ... ignore constant fp. There is not any good way to
1999 // to represent them here in dwarf.
2003 void DwarfDebug::emitDebugLocEntryLocation(const DebugLocEntry &Entry) {
2004 Asm->OutStreamer.AddComment("Loc expr size");
2005 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol();
2006 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol();
2007 Asm->EmitLabelDifference(end, begin, 2);
2008 Asm->OutStreamer.EmitLabel(begin);
2010 APByteStreamer Streamer(*Asm);
2011 emitDebugLocEntry(Streamer, Entry);
2013 Asm->OutStreamer.EmitLabel(end);
2016 // Emit locations into the debug loc section.
2017 void DwarfDebug::emitDebugLoc() {
2018 // Start the dwarf loc section.
2019 Asm->OutStreamer.SwitchSection(
2020 Asm->getObjFileLowering().getDwarfLocSection());
2021 unsigned char Size = Asm->getDataLayout().getPointerSize();
2022 for (const auto &DebugLoc : DotDebugLocEntries) {
2023 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2024 for (const auto &Entry : DebugLoc.List) {
2025 // Set up the range. This range is relative to the entry point of the
2026 // compile unit. This is a hard coded 0 for low_pc when we're emitting
2027 // ranges, or the DW_AT_low_pc on the compile unit otherwise.
2028 const DwarfCompileUnit *CU = Entry.getCU();
2029 if (CU->getRanges().size() == 1) {
2030 // Grab the begin symbol from the first range as our base.
2031 const MCSymbol *Base = CU->getRanges()[0].getStart();
2032 Asm->EmitLabelDifference(Entry.getBeginSym(), Base, Size);
2033 Asm->EmitLabelDifference(Entry.getEndSym(), Base, Size);
2035 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size);
2036 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size);
2039 emitDebugLocEntryLocation(Entry);
2041 Asm->OutStreamer.EmitIntValue(0, Size);
2042 Asm->OutStreamer.EmitIntValue(0, Size);
2046 void DwarfDebug::emitDebugLocDWO() {
2047 Asm->OutStreamer.SwitchSection(
2048 Asm->getObjFileLowering().getDwarfLocDWOSection());
2049 for (const auto &DebugLoc : DotDebugLocEntries) {
2050 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2051 for (const auto &Entry : DebugLoc.List) {
2052 // Just always use start_length for now - at least that's one address
2053 // rather than two. We could get fancier and try to, say, reuse an
2054 // address we know we've emitted elsewhere (the start of the function?
2055 // The start of the CU or CU subrange that encloses this range?)
2056 Asm->EmitInt8(dwarf::DW_LLE_start_length_entry);
2057 unsigned idx = AddrPool.getIndex(Entry.getBeginSym());
2058 Asm->EmitULEB128(idx);
2059 Asm->EmitLabelDifference(Entry.getEndSym(), Entry.getBeginSym(), 4);
2061 emitDebugLocEntryLocation(Entry);
2063 Asm->EmitInt8(dwarf::DW_LLE_end_of_list_entry);
2068 const MCSymbol *Start, *End;
2071 // Emit a debug aranges section, containing a CU lookup for any
2072 // address we can tie back to a CU.
2073 void DwarfDebug::emitDebugARanges() {
2074 // Start the dwarf aranges section.
2075 Asm->OutStreamer.SwitchSection(
2076 Asm->getObjFileLowering().getDwarfARangesSection());
2078 typedef DenseMap<DwarfCompileUnit *, std::vector<ArangeSpan>> SpansType;
2082 // Build a list of sections used.
2083 std::vector<const MCSection *> Sections;
2084 for (const auto &it : SectionMap) {
2085 const MCSection *Section = it.first;
2086 Sections.push_back(Section);
2089 // Sort the sections into order.
2090 // This is only done to ensure consistent output order across different runs.
2091 std::sort(Sections.begin(), Sections.end(), SectionSort);
2093 // Build a set of address spans, sorted by CU.
2094 for (const MCSection *Section : Sections) {
2095 SmallVector<SymbolCU, 8> &List = SectionMap[Section];
2096 if (List.size() < 2)
2099 // Sort the symbols by offset within the section.
2100 std::sort(List.begin(), List.end(),
2101 [&](const SymbolCU &A, const SymbolCU &B) {
2102 unsigned IA = A.Sym ? Asm->OutStreamer.GetSymbolOrder(A.Sym) : 0;
2103 unsigned IB = B.Sym ? Asm->OutStreamer.GetSymbolOrder(B.Sym) : 0;
2105 // Symbols with no order assigned should be placed at the end.
2106 // (e.g. section end labels)
2114 // If we have no section (e.g. common), just write out
2115 // individual spans for each symbol.
2117 for (const SymbolCU &Cur : List) {
2119 Span.Start = Cur.Sym;
2122 Spans[Cur.CU].push_back(Span);
2125 // Build spans between each label.
2126 const MCSymbol *StartSym = List[0].Sym;
2127 for (size_t n = 1, e = List.size(); n < e; n++) {
2128 const SymbolCU &Prev = List[n - 1];
2129 const SymbolCU &Cur = List[n];
2131 // Try and build the longest span we can within the same CU.
2132 if (Cur.CU != Prev.CU) {
2134 Span.Start = StartSym;
2136 Spans[Prev.CU].push_back(Span);
2143 unsigned PtrSize = Asm->getDataLayout().getPointerSize();
2145 // Build a list of CUs used.
2146 std::vector<DwarfCompileUnit *> CUs;
2147 for (const auto &it : Spans) {
2148 DwarfCompileUnit *CU = it.first;
2152 // Sort the CU list (again, to ensure consistent output order).
2153 std::sort(CUs.begin(), CUs.end(), [](const DwarfUnit *A, const DwarfUnit *B) {
2154 return A->getUniqueID() < B->getUniqueID();
2157 // Emit an arange table for each CU we used.
2158 for (DwarfCompileUnit *CU : CUs) {
2159 std::vector<ArangeSpan> &List = Spans[CU];
2161 // Emit size of content not including length itself.
2162 unsigned ContentSize =
2163 sizeof(int16_t) + // DWARF ARange version number
2164 sizeof(int32_t) + // Offset of CU in the .debug_info section
2165 sizeof(int8_t) + // Pointer Size (in bytes)
2166 sizeof(int8_t); // Segment Size (in bytes)
2168 unsigned TupleSize = PtrSize * 2;
2170 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple.
2172 OffsetToAlignment(sizeof(int32_t) + ContentSize, TupleSize);
2174 ContentSize += Padding;
2175 ContentSize += (List.size() + 1) * TupleSize;
2177 // For each compile unit, write the list of spans it covers.
2178 Asm->OutStreamer.AddComment("Length of ARange Set");
2179 Asm->EmitInt32(ContentSize);
2180 Asm->OutStreamer.AddComment("DWARF Arange version number");
2181 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION);
2182 Asm->OutStreamer.AddComment("Offset Into Debug Info Section");
2183 Asm->EmitSectionOffset(CU->getLocalLabelBegin(), CU->getLocalSectionSym());
2184 Asm->OutStreamer.AddComment("Address Size (in bytes)");
2185 Asm->EmitInt8(PtrSize);
2186 Asm->OutStreamer.AddComment("Segment Size (in bytes)");
2189 Asm->OutStreamer.EmitFill(Padding, 0xff);
2191 for (const ArangeSpan &Span : List) {
2192 Asm->EmitLabelReference(Span.Start, PtrSize);
2194 // Calculate the size as being from the span start to it's end.
2196 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize);
2198 // For symbols without an end marker (e.g. common), we
2199 // write a single arange entry containing just that one symbol.
2200 uint64_t Size = SymSize[Span.Start];
2204 Asm->OutStreamer.EmitIntValue(Size, PtrSize);
2208 Asm->OutStreamer.AddComment("ARange terminator");
2209 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2210 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2214 // Emit visible names into a debug ranges section.
2215 void DwarfDebug::emitDebugRanges() {
2216 // Start the dwarf ranges section.
2217 Asm->OutStreamer.SwitchSection(
2218 Asm->getObjFileLowering().getDwarfRangesSection());
2220 // Size for our labels.
2221 unsigned char Size = Asm->getDataLayout().getPointerSize();
2223 // Grab the specific ranges for the compile units in the module.
2224 for (const auto &I : CUMap) {
2225 DwarfCompileUnit *TheCU = I.second;
2227 // Iterate over the misc ranges for the compile units in the module.
2228 for (const RangeSpanList &List : TheCU->getRangeLists()) {
2229 // Emit our symbol so we can find the beginning of the range.
2230 Asm->OutStreamer.EmitLabel(List.getSym());
2232 for (const RangeSpan &Range : List.getRanges()) {
2233 const MCSymbol *Begin = Range.getStart();
2234 const MCSymbol *End = Range.getEnd();
2235 assert(Begin && "Range without a begin symbol?");
2236 assert(End && "Range without an end symbol?");
2237 if (TheCU->getRanges().size() == 1) {
2238 // Grab the begin symbol from the first range as our base.
2239 const MCSymbol *Base = TheCU->getRanges()[0].getStart();
2240 Asm->EmitLabelDifference(Begin, Base, Size);
2241 Asm->EmitLabelDifference(End, Base, Size);
2243 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2244 Asm->OutStreamer.EmitSymbolValue(End, Size);
2248 // And terminate the list with two 0 values.
2249 Asm->OutStreamer.EmitIntValue(0, Size);
2250 Asm->OutStreamer.EmitIntValue(0, Size);
2253 // Now emit a range for the CU itself.
2254 if (TheCU->getRanges().size() > 1) {
2255 Asm->OutStreamer.EmitLabel(
2256 Asm->GetTempSymbol("cu_ranges", TheCU->getUniqueID()));
2257 for (const RangeSpan &Range : TheCU->getRanges()) {
2258 const MCSymbol *Begin = Range.getStart();
2259 const MCSymbol *End = Range.getEnd();
2260 assert(Begin && "Range without a begin symbol?");
2261 assert(End && "Range without an end symbol?");
2262 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2263 Asm->OutStreamer.EmitSymbolValue(End, Size);
2265 // And terminate the list with two 0 values.
2266 Asm->OutStreamer.EmitIntValue(0, Size);
2267 Asm->OutStreamer.EmitIntValue(0, Size);
2272 // DWARF5 Experimental Separate Dwarf emitters.
2274 void DwarfDebug::initSkeletonUnit(const DwarfUnit &U, DIE &Die,
2275 std::unique_ptr<DwarfUnit> NewU) {
2276 NewU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name,
2277 U.getCUNode().getSplitDebugFilename());
2279 if (!CompilationDir.empty())
2280 NewU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
2282 addGnuPubAttributes(*NewU, Die);
2284 SkeletonHolder.addUnit(std::move(NewU));
2287 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list,
2288 // DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id,
2289 // DW_AT_addr_base, DW_AT_ranges_base.
2290 DwarfCompileUnit &DwarfDebug::constructSkeletonCU(const DwarfCompileUnit &CU) {
2292 auto OwnedUnit = make_unique<DwarfCompileUnit>(
2293 CU.getUniqueID(), CU.getCUNode(), Asm, this, &SkeletonHolder);
2294 DwarfCompileUnit &NewCU = *OwnedUnit;
2295 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
2296 DwarfInfoSectionSym);
2298 NewCU.initStmtList(DwarfLineSectionSym);
2300 initSkeletonUnit(CU, NewCU.getUnitDie(), std::move(OwnedUnit));
2305 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_dwo_name,
2307 DwarfTypeUnit &DwarfDebug::constructSkeletonTU(DwarfTypeUnit &TU) {
2308 DwarfCompileUnit &CU = static_cast<DwarfCompileUnit &>(
2309 *SkeletonHolder.getUnits()[TU.getCU().getUniqueID()]);
2311 auto OwnedUnit = make_unique<DwarfTypeUnit>(TU.getUniqueID(), CU, Asm, this,
2313 DwarfTypeUnit &NewTU = *OwnedUnit;
2314 NewTU.setTypeSignature(TU.getTypeSignature());
2315 NewTU.setType(nullptr);
2317 Asm->getObjFileLowering().getDwarfTypesSection(TU.getTypeSignature()));
2319 initSkeletonUnit(TU, NewTU.getUnitDie(), std::move(OwnedUnit));
2323 // Emit the .debug_info.dwo section for separated dwarf. This contains the
2324 // compile units that would normally be in debug_info.
2325 void DwarfDebug::emitDebugInfoDWO() {
2326 assert(useSplitDwarf() && "No split dwarf debug info?");
2327 // Don't pass an abbrev symbol, using a constant zero instead so as not to
2328 // emit relocations into the dwo file.
2329 InfoHolder.emitUnits(this, /* AbbrevSymbol */ nullptr);
2332 // Emit the .debug_abbrev.dwo section for separated dwarf. This contains the
2333 // abbreviations for the .debug_info.dwo section.
2334 void DwarfDebug::emitDebugAbbrevDWO() {
2335 assert(useSplitDwarf() && "No split dwarf?");
2336 InfoHolder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection());
2339 void DwarfDebug::emitDebugLineDWO() {
2340 assert(useSplitDwarf() && "No split dwarf?");
2341 Asm->OutStreamer.SwitchSection(
2342 Asm->getObjFileLowering().getDwarfLineDWOSection());
2343 SplitTypeUnitFileTable.Emit(Asm->OutStreamer);
2346 // Emit the .debug_str.dwo section for separated dwarf. This contains the
2347 // string section and is identical in format to traditional .debug_str
2349 void DwarfDebug::emitDebugStrDWO() {
2350 assert(useSplitDwarf() && "No split dwarf?");
2351 const MCSection *OffSec =
2352 Asm->getObjFileLowering().getDwarfStrOffDWOSection();
2353 const MCSymbol *StrSym = DwarfStrSectionSym;
2354 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(),
2358 MCDwarfDwoLineTable *DwarfDebug::getDwoLineTable(const DwarfCompileUnit &CU) {
2359 if (!useSplitDwarf())
2362 SplitTypeUnitFileTable.setCompilationDir(CU.getCUNode().getDirectory());
2363 return &SplitTypeUnitFileTable;
2366 static uint64_t makeTypeSignature(StringRef Identifier) {
2368 Hash.update(Identifier);
2369 // ... take the least significant 8 bytes and return those. Our MD5
2370 // implementation always returns its results in little endian, swap bytes
2372 MD5::MD5Result Result;
2374 return *reinterpret_cast<support::ulittle64_t *>(Result + 8);
2377 void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU,
2378 StringRef Identifier, DIE &RefDie,
2379 DICompositeType CTy) {
2380 // Fast path if we're building some type units and one has already used the
2381 // address pool we know we're going to throw away all this work anyway, so
2382 // don't bother building dependent types.
2383 if (!TypeUnitsUnderConstruction.empty() && AddrPool.hasBeenUsed())
2386 const DwarfTypeUnit *&TU = DwarfTypeUnits[CTy];
2388 CU.addDIETypeSignature(RefDie, *TU);
2392 bool TopLevelType = TypeUnitsUnderConstruction.empty();
2393 AddrPool.resetUsedFlag();
2396 make_unique<DwarfTypeUnit>(InfoHolder.getUnits().size(), CU, Asm, this,
2397 &InfoHolder, getDwoLineTable(CU));
2398 DwarfTypeUnit &NewTU = *OwnedUnit;
2399 DIE &UnitDie = NewTU.getUnitDie();
2401 TypeUnitsUnderConstruction.push_back(
2402 std::make_pair(std::move(OwnedUnit), CTy));
2404 NewTU.addUInt(UnitDie, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
2407 uint64_t Signature = makeTypeSignature(Identifier);
2408 NewTU.setTypeSignature(Signature);
2410 if (!useSplitDwarf())
2411 CU.applyStmtList(UnitDie);
2413 // FIXME: Skip using COMDAT groups for type units in the .dwo file once tools
2414 // such as DWP ( http://gcc.gnu.org/wiki/DebugFissionDWP ) can cope with it.
2417 ? Asm->getObjFileLowering().getDwarfTypesDWOSection(Signature)
2418 : Asm->getObjFileLowering().getDwarfTypesSection(Signature));
2420 NewTU.setType(NewTU.createTypeDIE(CTy));
2423 auto TypeUnitsToAdd = std::move(TypeUnitsUnderConstruction);
2424 TypeUnitsUnderConstruction.clear();
2426 // Types referencing entries in the address table cannot be placed in type
2428 if (AddrPool.hasBeenUsed()) {
2430 // Remove all the types built while building this type.
2431 // This is pessimistic as some of these types might not be dependent on
2432 // the type that used an address.
2433 for (const auto &TU : TypeUnitsToAdd)
2434 DwarfTypeUnits.erase(TU.second);
2436 // Construct this type in the CU directly.
2437 // This is inefficient because all the dependent types will be rebuilt
2438 // from scratch, including building them in type units, discovering that
2439 // they depend on addresses, throwing them out and rebuilding them.
2440 CU.constructTypeDIE(RefDie, CTy);
2444 // If the type wasn't dependent on fission addresses, finish adding the type
2445 // and all its dependent types.
2446 for (auto &TU : TypeUnitsToAdd) {
2447 if (useSplitDwarf())
2448 TU.first->setSkeleton(constructSkeletonTU(*TU.first));
2449 InfoHolder.addUnit(std::move(TU.first));
2452 CU.addDIETypeSignature(RefDie, NewTU);
2455 void DwarfDebug::attachLowHighPC(DwarfCompileUnit &Unit, DIE &D,
2456 MCSymbol *Begin, MCSymbol *End) {
2457 assert(Begin && "Begin label should not be null!");
2458 assert(End && "End label should not be null!");
2459 assert(Begin->isDefined() && "Invalid starting label");
2460 assert(End->isDefined() && "Invalid end label");
2462 Unit.addLabelAddress(D, dwarf::DW_AT_low_pc, Begin);
2463 if (DwarfVersion < 4)
2464 Unit.addLabelAddress(D, dwarf::DW_AT_high_pc, End);
2466 Unit.addLabelDelta(D, dwarf::DW_AT_high_pc, End, Begin);
2469 // Accelerator table mutators - add each name along with its companion
2470 // DIE to the proper table while ensuring that the name that we're going
2471 // to reference is in the string table. We do this since the names we
2472 // add may not only be identical to the names in the DIE.
2473 void DwarfDebug::addAccelName(StringRef Name, const DIE &Die) {
2474 if (!useDwarfAccelTables())
2476 AccelNames.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2480 void DwarfDebug::addAccelObjC(StringRef Name, const DIE &Die) {
2481 if (!useDwarfAccelTables())
2483 AccelObjC.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2487 void DwarfDebug::addAccelNamespace(StringRef Name, const DIE &Die) {
2488 if (!useDwarfAccelTables())
2490 AccelNamespace.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2494 void DwarfDebug::addAccelType(StringRef Name, const DIE &Die, char Flags) {
2495 if (!useDwarfAccelTables())
2497 AccelTypes.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),