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: Consider the time-space tradeoff of just storing the unit pointer
790 // in the ConcreteVariables list, rather than looking it up again here.
791 // DIE::getUnit isn't simple - it walks parent pointers, etc.
792 DwarfCompileUnit *Unit = lookupUnit(VariableDie->getUnit());
794 DbgVariable *AbsVar = getExistingAbstractVariable(Var->getVariable());
795 if (AbsVar && AbsVar->getDIE()) {
796 Unit->addDIEEntry(*VariableDie, dwarf::DW_AT_abstract_origin,
799 Unit->applyVariableAttributes(*Var, *VariableDie);
803 void DwarfDebug::finishSubprogramDefinitions() {
804 const Module *M = MMI->getModule();
806 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
807 for (MDNode *N : CU_Nodes->operands()) {
808 DICompileUnit TheCU(N);
809 // Construct subprogram DIE and add variables DIEs.
810 DwarfCompileUnit *SPCU =
811 static_cast<DwarfCompileUnit *>(CUMap.lookup(TheCU));
812 DIArray Subprograms = TheCU.getSubprograms();
813 for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) {
814 DISubprogram SP(Subprograms.getElement(i));
815 // Perhaps the subprogram is in another CU (such as due to comdat
816 // folding, etc), in which case ignore it here.
817 if (SPMap[SP] != SPCU)
819 DIE *D = SPCU->getDIE(SP);
820 if (DIE *AbsSPDIE = AbstractSPDies.lookup(SP)) {
822 // If this subprogram has an abstract definition, reference that
823 SPCU->addDIEEntry(*D, dwarf::DW_AT_abstract_origin, *AbsSPDIE);
826 // Lazily construct the subprogram if we didn't see either concrete or
827 // inlined versions during codegen.
828 D = SPCU->getOrCreateSubprogramDIE(SP);
829 // And attach the attributes
830 SPCU->applySubprogramAttributesToDefinition(SP, *D);
837 // Collect info for variables that were optimized out.
838 void DwarfDebug::collectDeadVariables() {
839 const Module *M = MMI->getModule();
841 if (NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu")) {
842 for (MDNode *N : CU_Nodes->operands()) {
843 DICompileUnit TheCU(N);
844 // Construct subprogram DIE and add variables DIEs.
845 DwarfCompileUnit *SPCU =
846 static_cast<DwarfCompileUnit *>(CUMap.lookup(TheCU));
847 assert(SPCU && "Unable to find Compile Unit!");
848 DIArray Subprograms = TheCU.getSubprograms();
849 for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) {
850 DISubprogram SP(Subprograms.getElement(i));
851 if (ProcessedSPNodes.count(SP) != 0)
853 assert(SP.isSubprogram() &&
854 "CU's subprogram list contains a non-subprogram");
855 assert(SP.isDefinition() &&
856 "CU's subprogram list contains a subprogram declaration");
857 DIArray Variables = SP.getVariables();
858 if (Variables.getNumElements() == 0)
861 DIE *SPDIE = AbstractSPDies.lookup(SP);
863 SPDIE = SPCU->getDIE(SP);
865 for (unsigned vi = 0, ve = Variables.getNumElements(); vi != ve; ++vi) {
866 DIVariable DV(Variables.getElement(vi));
867 assert(DV.isVariable());
868 DbgVariable NewVar(DV, this);
869 auto VariableDie = SPCU->constructVariableDIE(NewVar);
870 SPCU->applyVariableAttributes(NewVar, *VariableDie);
871 SPDIE->addChild(std::move(VariableDie));
878 void DwarfDebug::finalizeModuleInfo() {
879 finishSubprogramDefinitions();
881 finishVariableDefinitions();
883 // Collect info for variables that were optimized out.
884 collectDeadVariables();
886 // Handle anything that needs to be done on a per-unit basis after
887 // all other generation.
888 for (const auto &TheU : getUnits()) {
889 // Emit DW_AT_containing_type attribute to connect types with their
890 // vtable holding type.
891 TheU->constructContainingTypeDIEs();
893 // Add CU specific attributes if we need to add any.
894 if (TheU->getUnitDie().getTag() == dwarf::DW_TAG_compile_unit) {
895 // If we're splitting the dwarf out now that we've got the entire
896 // CU then add the dwo id to it.
897 DwarfCompileUnit *SkCU =
898 static_cast<DwarfCompileUnit *>(TheU->getSkeleton());
899 if (useSplitDwarf()) {
900 // Emit a unique identifier for this CU.
901 uint64_t ID = DIEHash(Asm).computeCUSignature(TheU->getUnitDie());
902 TheU->addUInt(TheU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
903 dwarf::DW_FORM_data8, ID);
904 SkCU->addUInt(SkCU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
905 dwarf::DW_FORM_data8, ID);
907 // We don't keep track of which addresses are used in which CU so this
908 // is a bit pessimistic under LTO.
909 if (!AddrPool.isEmpty())
910 addSectionLabel(*Asm, *SkCU, SkCU->getUnitDie(),
911 dwarf::DW_AT_GNU_addr_base, DwarfAddrSectionSym,
912 DwarfAddrSectionSym);
913 if (!TheU->getRangeLists().empty())
914 addSectionLabel(*Asm, *SkCU, SkCU->getUnitDie(),
915 dwarf::DW_AT_GNU_ranges_base,
916 DwarfDebugRangeSectionSym, DwarfDebugRangeSectionSym);
919 // If we have code split among multiple sections or non-contiguous
920 // ranges of code then emit a DW_AT_ranges attribute on the unit that will
921 // remain in the .o file, otherwise add a DW_AT_low_pc.
922 // FIXME: We should use ranges allow reordering of code ala
923 // .subsections_via_symbols in mach-o. This would mean turning on
924 // ranges for all subprogram DIEs for mach-o.
925 DwarfCompileUnit &U =
926 SkCU ? *SkCU : static_cast<DwarfCompileUnit &>(*TheU);
927 unsigned NumRanges = TheU->getRanges().size();
930 addSectionLabel(*Asm, U, U.getUnitDie(), dwarf::DW_AT_ranges,
931 Asm->GetTempSymbol("cu_ranges", U.getUniqueID()),
932 DwarfDebugRangeSectionSym);
934 // A DW_AT_low_pc attribute may also be specified in combination with
935 // DW_AT_ranges to specify the default base address for use in
936 // location lists (see Section 2.6.2) and range lists (see Section
938 U.addUInt(U.getUnitDie(), dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr,
941 RangeSpan &Range = TheU->getRanges().back();
942 U.addLocalLabelAddress(U.getUnitDie(), dwarf::DW_AT_low_pc,
944 U.addLabelDelta(U.getUnitDie(), dwarf::DW_AT_high_pc, Range.getEnd(),
951 // Compute DIE offsets and sizes.
952 InfoHolder.computeSizeAndOffsets();
954 SkeletonHolder.computeSizeAndOffsets();
957 void DwarfDebug::endSections() {
958 // Filter labels by section.
959 for (const SymbolCU &SCU : ArangeLabels) {
960 if (SCU.Sym->isInSection()) {
961 // Make a note of this symbol and it's section.
962 const MCSection *Section = &SCU.Sym->getSection();
963 if (!Section->getKind().isMetadata())
964 SectionMap[Section].push_back(SCU);
966 // Some symbols (e.g. common/bss on mach-o) can have no section but still
967 // appear in the output. This sucks as we rely on sections to build
968 // arange spans. We can do it without, but it's icky.
969 SectionMap[nullptr].push_back(SCU);
973 // Build a list of sections used.
974 std::vector<const MCSection *> Sections;
975 for (const auto &it : SectionMap) {
976 const MCSection *Section = it.first;
977 Sections.push_back(Section);
980 // Sort the sections into order.
981 // This is only done to ensure consistent output order across different runs.
982 std::sort(Sections.begin(), Sections.end(), SectionSort);
984 // Add terminating symbols for each section.
985 for (unsigned ID = 0, E = Sections.size(); ID != E; ID++) {
986 const MCSection *Section = Sections[ID];
987 MCSymbol *Sym = nullptr;
990 // We can't call MCSection::getLabelEndName, as it's only safe to do so
991 // if we know the section name up-front. For user-created sections, the
992 // resulting label may not be valid to use as a label. (section names can
993 // use a greater set of characters on some systems)
994 Sym = Asm->GetTempSymbol("debug_end", ID);
995 Asm->OutStreamer.SwitchSection(Section);
996 Asm->OutStreamer.EmitLabel(Sym);
999 // Insert a final terminator.
1000 SectionMap[Section].push_back(SymbolCU(nullptr, Sym));
1004 // Emit all Dwarf sections that should come after the content.
1005 void DwarfDebug::endModule() {
1006 assert(CurFn == nullptr);
1007 assert(CurMI == nullptr);
1012 // End any existing sections.
1013 // TODO: Does this need to happen?
1016 // Finalize the debug info for the module.
1017 finalizeModuleInfo();
1021 // Emit all the DIEs into a debug info section.
1024 // Corresponding abbreviations into a abbrev section.
1025 emitAbbreviations();
1027 // Emit info into a debug aranges section.
1028 if (GenerateARangeSection)
1031 // Emit info into a debug ranges section.
1034 if (useSplitDwarf()) {
1037 emitDebugAbbrevDWO();
1039 // Emit DWO addresses.
1040 AddrPool.emit(*Asm, Asm->getObjFileLowering().getDwarfAddrSection());
1043 // Emit info into a debug loc section.
1046 // Emit info into the dwarf accelerator table sections.
1047 if (useDwarfAccelTables()) {
1050 emitAccelNamespaces();
1054 // Emit the pubnames and pubtypes sections if requested.
1055 if (HasDwarfPubSections) {
1056 emitDebugPubNames(GenerateGnuPubSections);
1057 emitDebugPubTypes(GenerateGnuPubSections);
1062 AbstractVariables.clear();
1064 // Reset these for the next Module if we have one.
1068 // Find abstract variable, if any, associated with Var.
1069 DbgVariable *DwarfDebug::getExistingAbstractVariable(const DIVariable &DV,
1070 DIVariable &Cleansed) {
1071 LLVMContext &Ctx = DV->getContext();
1072 // More then one inlined variable corresponds to one abstract variable.
1073 // FIXME: This duplication of variables when inlining should probably be
1074 // removed. It's done to allow each DIVariable to describe its location
1075 // because the DebugLoc on the dbg.value/declare isn't accurate. We should
1076 // make it accurate then remove this duplication/cleansing stuff.
1077 Cleansed = cleanseInlinedVariable(DV, Ctx);
1078 auto I = AbstractVariables.find(Cleansed);
1079 if (I != AbstractVariables.end())
1080 return I->second.get();
1084 DbgVariable *DwarfDebug::getExistingAbstractVariable(const DIVariable &DV) {
1085 DIVariable Cleansed;
1086 return getExistingAbstractVariable(DV, Cleansed);
1089 void DwarfDebug::createAbstractVariable(const DIVariable &Var,
1090 LexicalScope *Scope) {
1091 auto AbsDbgVariable = make_unique<DbgVariable>(Var, this);
1092 addScopeVariable(Scope, AbsDbgVariable.get());
1093 AbstractVariables[Var] = std::move(AbsDbgVariable);
1096 void DwarfDebug::ensureAbstractVariableIsCreated(const DIVariable &DV,
1097 const MDNode *ScopeNode) {
1098 DIVariable Cleansed = DV;
1099 if (getExistingAbstractVariable(DV, Cleansed))
1102 createAbstractVariable(Cleansed, LScopes.getOrCreateAbstractScope(ScopeNode));
1106 DwarfDebug::ensureAbstractVariableIsCreatedIfScoped(const DIVariable &DV,
1107 const MDNode *ScopeNode) {
1108 DIVariable Cleansed = DV;
1109 if (getExistingAbstractVariable(DV, Cleansed))
1112 if (LexicalScope *Scope = LScopes.findAbstractScope(ScopeNode))
1113 createAbstractVariable(Cleansed, Scope);
1116 // If Var is a current function argument then add it to CurrentFnArguments list.
1117 bool DwarfDebug::addCurrentFnArgument(DbgVariable *Var, LexicalScope *Scope) {
1118 if (!LScopes.isCurrentFunctionScope(Scope))
1120 DIVariable DV = Var->getVariable();
1121 if (DV.getTag() != dwarf::DW_TAG_arg_variable)
1123 unsigned ArgNo = DV.getArgNumber();
1127 size_t Size = CurrentFnArguments.size();
1129 CurrentFnArguments.resize(CurFn->getFunction()->arg_size());
1130 // llvm::Function argument size is not good indicator of how many
1131 // arguments does the function have at source level.
1133 CurrentFnArguments.resize(ArgNo * 2);
1134 CurrentFnArguments[ArgNo - 1] = Var;
1138 // Collect variable information from side table maintained by MMI.
1139 void DwarfDebug::collectVariableInfoFromMMITable(
1140 SmallPtrSet<const MDNode *, 16> &Processed) {
1141 for (const auto &VI : MMI->getVariableDbgInfo()) {
1144 Processed.insert(VI.Var);
1145 DIVariable DV(VI.Var);
1146 LexicalScope *Scope = LScopes.findLexicalScope(VI.Loc);
1148 // If variable scope is not found then skip this variable.
1152 ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode());
1153 ConcreteVariables.push_back(make_unique<DbgVariable>(DV, this));
1154 DbgVariable *RegVar = ConcreteVariables.back().get();
1155 RegVar->setFrameIndex(VI.Slot);
1156 addScopeVariable(Scope, RegVar);
1160 // Get .debug_loc entry for the instruction range starting at MI.
1161 static DebugLocEntry::Value getDebugLocValue(const MachineInstr *MI) {
1162 const MDNode *Var = MI->getDebugVariable();
1164 assert(MI->getNumOperands() == 3);
1165 if (MI->getOperand(0).isReg()) {
1166 MachineLocation MLoc;
1167 // If the second operand is an immediate, this is a
1168 // register-indirect address.
1169 if (!MI->getOperand(1).isImm())
1170 MLoc.set(MI->getOperand(0).getReg());
1172 MLoc.set(MI->getOperand(0).getReg(), MI->getOperand(1).getImm());
1173 return DebugLocEntry::Value(Var, MLoc);
1175 if (MI->getOperand(0).isImm())
1176 return DebugLocEntry::Value(Var, MI->getOperand(0).getImm());
1177 if (MI->getOperand(0).isFPImm())
1178 return DebugLocEntry::Value(Var, MI->getOperand(0).getFPImm());
1179 if (MI->getOperand(0).isCImm())
1180 return DebugLocEntry::Value(Var, MI->getOperand(0).getCImm());
1182 llvm_unreachable("Unexpected 3 operand DBG_VALUE instruction!");
1185 // Find variables for each lexical scope.
1187 DwarfDebug::collectVariableInfo(SmallPtrSet<const MDNode *, 16> &Processed) {
1188 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1189 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1191 // Grab the variable info that was squirreled away in the MMI side-table.
1192 collectVariableInfoFromMMITable(Processed);
1194 for (const auto &I : DbgValues) {
1195 DIVariable DV(I.first);
1196 if (Processed.count(DV))
1199 // Instruction ranges, specifying where DV is accessible.
1200 const auto &Ranges = I.second;
1204 LexicalScope *Scope = nullptr;
1205 if (DV.getTag() == dwarf::DW_TAG_arg_variable &&
1206 DISubprogram(DV.getContext()).describes(CurFn->getFunction()))
1207 Scope = LScopes.getCurrentFunctionScope();
1208 else if (MDNode *IA = DV.getInlinedAt()) {
1209 DebugLoc DL = DebugLoc::getFromDILocation(IA);
1210 Scope = LScopes.findInlinedScope(DebugLoc::get(
1211 DL.getLine(), DL.getCol(), DV.getContext(), IA));
1213 Scope = LScopes.findLexicalScope(DV.getContext());
1214 // If variable scope is not found then skip this variable.
1218 Processed.insert(DV);
1219 const MachineInstr *MInsn = Ranges.front().first;
1220 assert(MInsn->isDebugValue() && "History must begin with debug value");
1221 ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode());
1222 ConcreteVariables.push_back(make_unique<DbgVariable>(MInsn, this));
1223 DbgVariable *RegVar = ConcreteVariables.back().get();
1224 addScopeVariable(Scope, RegVar);
1226 // Check if the first DBG_VALUE is valid for the rest of the function.
1227 if (Ranges.size() == 1 && Ranges.front().second == nullptr)
1230 // Handle multiple DBG_VALUE instructions describing one variable.
1231 RegVar->setDotDebugLocOffset(DotDebugLocEntries.size());
1233 DotDebugLocEntries.resize(DotDebugLocEntries.size() + 1);
1234 DebugLocList &LocList = DotDebugLocEntries.back();
1236 Asm->GetTempSymbol("debug_loc", DotDebugLocEntries.size() - 1);
1237 SmallVector<DebugLocEntry, 4> &DebugLoc = LocList.List;
1238 for (auto I = Ranges.begin(), E = Ranges.end(); I != E; ++I) {
1239 const MachineInstr *Begin = I->first;
1240 const MachineInstr *End = I->second;
1241 assert(Begin->isDebugValue() && "Invalid History entry");
1243 // Check if a variable is unaccessible in this range.
1244 if (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() &&
1245 !Begin->getOperand(0).getReg())
1247 DEBUG(dbgs() << "DotDebugLoc Pair:\n" << "\t" << *Begin);
1249 DEBUG(dbgs() << "\t" << *End);
1251 DEBUG(dbgs() << "\tNULL\n");
1253 const MCSymbol *StartLabel = getLabelBeforeInsn(Begin);
1254 assert(StartLabel && "Forgot label before DBG_VALUE starting a range!");
1256 const MCSymbol *EndLabel;
1258 EndLabel = getLabelAfterInsn(End);
1259 else if (std::next(I) == Ranges.end())
1260 EndLabel = FunctionEndSym;
1262 EndLabel = getLabelBeforeInsn(std::next(I)->first);
1263 assert(EndLabel && "Forgot label after instruction ending a range!");
1265 DebugLocEntry Loc(StartLabel, EndLabel, getDebugLocValue(Begin), TheCU);
1266 if (DebugLoc.empty() || !DebugLoc.back().Merge(Loc))
1267 DebugLoc.push_back(std::move(Loc));
1271 // Collect info for variables that were optimized out.
1272 DIArray Variables = DISubprogram(FnScope->getScopeNode()).getVariables();
1273 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1274 DIVariable DV(Variables.getElement(i));
1275 assert(DV.isVariable());
1276 if (!Processed.insert(DV))
1278 if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext())) {
1279 ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode());
1280 ConcreteVariables.push_back(make_unique<DbgVariable>(DV, this));
1281 addScopeVariable(Scope, ConcreteVariables.back().get());
1286 // Return Label preceding the instruction.
1287 MCSymbol *DwarfDebug::getLabelBeforeInsn(const MachineInstr *MI) {
1288 MCSymbol *Label = LabelsBeforeInsn.lookup(MI);
1289 assert(Label && "Didn't insert label before instruction");
1293 // Return Label immediately following the instruction.
1294 MCSymbol *DwarfDebug::getLabelAfterInsn(const MachineInstr *MI) {
1295 return LabelsAfterInsn.lookup(MI);
1298 // Process beginning of an instruction.
1299 void DwarfDebug::beginInstruction(const MachineInstr *MI) {
1300 assert(CurMI == nullptr);
1302 // Check if source location changes, but ignore DBG_VALUE locations.
1303 if (!MI->isDebugValue()) {
1304 DebugLoc DL = MI->getDebugLoc();
1305 if (DL != PrevInstLoc && (!DL.isUnknown() || UnknownLocations)) {
1308 if (DL == PrologEndLoc) {
1309 Flags |= DWARF2_FLAG_PROLOGUE_END;
1310 PrologEndLoc = DebugLoc();
1312 if (PrologEndLoc.isUnknown())
1313 Flags |= DWARF2_FLAG_IS_STMT;
1315 if (!DL.isUnknown()) {
1316 const MDNode *Scope = DL.getScope(Asm->MF->getFunction()->getContext());
1317 recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags);
1319 recordSourceLine(0, 0, nullptr, 0);
1323 // Insert labels where requested.
1324 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1325 LabelsBeforeInsn.find(MI);
1328 if (I == LabelsBeforeInsn.end())
1331 // Label already assigned.
1336 PrevLabel = MMI->getContext().CreateTempSymbol();
1337 Asm->OutStreamer.EmitLabel(PrevLabel);
1339 I->second = PrevLabel;
1342 // Process end of an instruction.
1343 void DwarfDebug::endInstruction() {
1344 assert(CurMI != nullptr);
1345 // Don't create a new label after DBG_VALUE instructions.
1346 // They don't generate code.
1347 if (!CurMI->isDebugValue())
1348 PrevLabel = nullptr;
1350 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1351 LabelsAfterInsn.find(CurMI);
1355 if (I == LabelsAfterInsn.end())
1358 // Label already assigned.
1362 // We need a label after this instruction.
1364 PrevLabel = MMI->getContext().CreateTempSymbol();
1365 Asm->OutStreamer.EmitLabel(PrevLabel);
1367 I->second = PrevLabel;
1370 // Each LexicalScope has first instruction and last instruction to mark
1371 // beginning and end of a scope respectively. Create an inverse map that list
1372 // scopes starts (and ends) with an instruction. One instruction may start (or
1373 // end) multiple scopes. Ignore scopes that are not reachable.
1374 void DwarfDebug::identifyScopeMarkers() {
1375 SmallVector<LexicalScope *, 4> WorkList;
1376 WorkList.push_back(LScopes.getCurrentFunctionScope());
1377 while (!WorkList.empty()) {
1378 LexicalScope *S = WorkList.pop_back_val();
1380 const SmallVectorImpl<LexicalScope *> &Children = S->getChildren();
1381 if (!Children.empty())
1382 WorkList.append(Children.begin(), Children.end());
1384 if (S->isAbstractScope())
1387 for (const InsnRange &R : S->getRanges()) {
1388 assert(R.first && "InsnRange does not have first instruction!");
1389 assert(R.second && "InsnRange does not have second instruction!");
1390 requestLabelBeforeInsn(R.first);
1391 requestLabelAfterInsn(R.second);
1396 static DebugLoc findPrologueEndLoc(const MachineFunction *MF) {
1397 // First known non-DBG_VALUE and non-frame setup location marks
1398 // the beginning of the function body.
1399 for (const auto &MBB : *MF)
1400 for (const auto &MI : MBB)
1401 if (!MI.isDebugValue() && !MI.getFlag(MachineInstr::FrameSetup) &&
1402 !MI.getDebugLoc().isUnknown())
1403 return MI.getDebugLoc();
1407 // Gather pre-function debug information. Assumes being called immediately
1408 // after the function entry point has been emitted.
1409 void DwarfDebug::beginFunction(const MachineFunction *MF) {
1412 // If there's no debug info for the function we're not going to do anything.
1413 if (!MMI->hasDebugInfo())
1416 // Grab the lexical scopes for the function, if we don't have any of those
1417 // then we're not going to be able to do anything.
1418 LScopes.initialize(*MF);
1419 if (LScopes.empty())
1422 assert(DbgValues.empty() && "DbgValues map wasn't cleaned!");
1424 // Make sure that each lexical scope will have a begin/end label.
1425 identifyScopeMarkers();
1427 // Set DwarfDwarfCompileUnitID in MCContext to the Compile Unit this function
1428 // belongs to so that we add to the correct per-cu line table in the
1430 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1431 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1432 assert(TheCU && "Unable to find compile unit!");
1433 if (Asm->OutStreamer.hasRawTextSupport())
1434 // Use a single line table if we are generating assembly.
1435 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1437 Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID());
1439 // Emit a label for the function so that we have a beginning address.
1440 FunctionBeginSym = Asm->GetTempSymbol("func_begin", Asm->getFunctionNumber());
1441 // Assumes in correct section after the entry point.
1442 Asm->OutStreamer.EmitLabel(FunctionBeginSym);
1444 // Calculate history for local variables.
1445 calculateDbgValueHistory(MF, Asm->TM.getRegisterInfo(), DbgValues);
1447 // Request labels for the full history.
1448 for (const auto &I : DbgValues) {
1449 const auto &Ranges = I.second;
1453 // The first mention of a function argument gets the FunctionBeginSym
1454 // label, so arguments are visible when breaking at function entry.
1455 DIVariable DV(I.first);
1456 if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable &&
1457 getDISubprogram(DV.getContext()).describes(MF->getFunction()))
1458 LabelsBeforeInsn[Ranges.front().first] = FunctionBeginSym;
1460 for (const auto &Range : Ranges) {
1461 requestLabelBeforeInsn(Range.first);
1463 requestLabelAfterInsn(Range.second);
1467 PrevInstLoc = DebugLoc();
1468 PrevLabel = FunctionBeginSym;
1470 // Record beginning of function.
1471 PrologEndLoc = findPrologueEndLoc(MF);
1472 if (!PrologEndLoc.isUnknown()) {
1473 DebugLoc FnStartDL =
1474 PrologEndLoc.getFnDebugLoc(MF->getFunction()->getContext());
1476 FnStartDL.getLine(), FnStartDL.getCol(),
1477 FnStartDL.getScope(MF->getFunction()->getContext()),
1478 // We'd like to list the prologue as "not statements" but GDB behaves
1479 // poorly if we do that. Revisit this with caution/GDB (7.5+) testing.
1480 DWARF2_FLAG_IS_STMT);
1484 void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) {
1485 if (addCurrentFnArgument(Var, LS))
1487 SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS];
1488 DIVariable DV = Var->getVariable();
1489 // Variables with positive arg numbers are parameters.
1490 if (unsigned ArgNum = DV.getArgNumber()) {
1491 // Keep all parameters in order at the start of the variable list to ensure
1492 // function types are correct (no out-of-order parameters)
1494 // This could be improved by only doing it for optimized builds (unoptimized
1495 // builds have the right order to begin with), searching from the back (this
1496 // would catch the unoptimized case quickly), or doing a binary search
1497 // rather than linear search.
1498 SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin();
1499 while (I != Vars.end()) {
1500 unsigned CurNum = (*I)->getVariable().getArgNumber();
1501 // A local (non-parameter) variable has been found, insert immediately
1505 // A later indexed parameter has been found, insert immediately before it.
1506 if (CurNum > ArgNum)
1510 Vars.insert(I, Var);
1514 Vars.push_back(Var);
1517 // Gather and emit post-function debug information.
1518 void DwarfDebug::endFunction(const MachineFunction *MF) {
1519 // Every beginFunction(MF) call should be followed by an endFunction(MF) call,
1520 // though the beginFunction may not be called at all.
1521 // We should handle both cases.
1525 assert(CurFn == MF);
1526 assert(CurFn != nullptr);
1528 if (!MMI->hasDebugInfo() || LScopes.empty()) {
1529 // If we don't have a lexical scope for this function then there will
1530 // be a hole in the range information. Keep note of this by setting the
1531 // previously used section to nullptr.
1532 PrevSection = nullptr;
1538 // Define end label for subprogram.
1539 FunctionEndSym = Asm->GetTempSymbol("func_end", Asm->getFunctionNumber());
1540 // Assumes in correct section after the entry point.
1541 Asm->OutStreamer.EmitLabel(FunctionEndSym);
1543 // Set DwarfDwarfCompileUnitID in MCContext to default value.
1544 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1546 SmallPtrSet<const MDNode *, 16> ProcessedVars;
1547 collectVariableInfo(ProcessedVars);
1549 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1550 DwarfCompileUnit &TheCU = *SPMap.lookup(FnScope->getScopeNode());
1552 // Construct abstract scopes.
1553 for (LexicalScope *AScope : LScopes.getAbstractScopesList()) {
1554 DISubprogram SP(AScope->getScopeNode());
1555 if (!SP.isSubprogram())
1557 // Collect info for variables that were optimized out.
1558 DIArray Variables = SP.getVariables();
1559 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1560 DIVariable DV(Variables.getElement(i));
1561 assert(DV && DV.isVariable());
1562 if (!ProcessedVars.insert(DV))
1564 ensureAbstractVariableIsCreated(DV, DV.getContext());
1566 constructAbstractSubprogramScopeDIE(TheCU, AScope);
1569 DIE &CurFnDIE = constructSubprogramScopeDIE(TheCU, FnScope);
1570 if (!CurFn->getTarget().Options.DisableFramePointerElim(*CurFn))
1571 TheCU.addFlag(CurFnDIE, dwarf::DW_AT_APPLE_omit_frame_ptr);
1573 // Add the range of this function to the list of ranges for the CU.
1574 RangeSpan Span(FunctionBeginSym, FunctionEndSym);
1575 TheCU.addRange(std::move(Span));
1576 PrevSection = Asm->getCurrentSection();
1580 // Ownership of DbgVariables is a bit subtle - ScopeVariables owns all the
1581 // DbgVariables except those that are also in AbstractVariables (since they
1582 // can be used cross-function)
1583 ScopeVariables.clear();
1584 CurrentFnArguments.clear();
1586 LabelsBeforeInsn.clear();
1587 LabelsAfterInsn.clear();
1588 PrevLabel = nullptr;
1592 // Register a source line with debug info. Returns the unique label that was
1593 // emitted and which provides correspondence to the source line list.
1594 void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S,
1599 unsigned Discriminator = 0;
1600 if (DIScope Scope = DIScope(S)) {
1601 assert(Scope.isScope());
1602 Fn = Scope.getFilename();
1603 Dir = Scope.getDirectory();
1604 if (Scope.isLexicalBlock())
1605 Discriminator = DILexicalBlock(S).getDiscriminator();
1607 unsigned CUID = Asm->OutStreamer.getContext().getDwarfCompileUnitID();
1608 Src = static_cast<DwarfCompileUnit &>(*InfoHolder.getUnits()[CUID])
1609 .getOrCreateSourceID(Fn, Dir);
1611 Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0,
1615 //===----------------------------------------------------------------------===//
1617 //===----------------------------------------------------------------------===//
1619 // Emit initial Dwarf sections with a label at the start of each one.
1620 void DwarfDebug::emitSectionLabels() {
1621 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
1623 // Dwarf sections base addresses.
1624 DwarfInfoSectionSym =
1625 emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info");
1626 if (useSplitDwarf())
1627 DwarfInfoDWOSectionSym =
1628 emitSectionSym(Asm, TLOF.getDwarfInfoDWOSection(), "section_info_dwo");
1629 DwarfAbbrevSectionSym =
1630 emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev");
1631 if (useSplitDwarf())
1632 DwarfAbbrevDWOSectionSym = emitSectionSym(
1633 Asm, TLOF.getDwarfAbbrevDWOSection(), "section_abbrev_dwo");
1634 if (GenerateARangeSection)
1635 emitSectionSym(Asm, TLOF.getDwarfARangesSection());
1637 DwarfLineSectionSym =
1638 emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line");
1639 if (GenerateGnuPubSections) {
1640 DwarfGnuPubNamesSectionSym =
1641 emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection());
1642 DwarfGnuPubTypesSectionSym =
1643 emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection());
1644 } else if (HasDwarfPubSections) {
1645 emitSectionSym(Asm, TLOF.getDwarfPubNamesSection());
1646 emitSectionSym(Asm, TLOF.getDwarfPubTypesSection());
1649 DwarfStrSectionSym =
1650 emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string");
1651 if (useSplitDwarf()) {
1652 DwarfStrDWOSectionSym =
1653 emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string");
1654 DwarfAddrSectionSym =
1655 emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec");
1656 DwarfDebugLocSectionSym =
1657 emitSectionSym(Asm, TLOF.getDwarfLocDWOSection(), "skel_loc");
1659 DwarfDebugLocSectionSym =
1660 emitSectionSym(Asm, TLOF.getDwarfLocSection(), "section_debug_loc");
1661 DwarfDebugRangeSectionSym =
1662 emitSectionSym(Asm, TLOF.getDwarfRangesSection(), "debug_range");
1665 // Recursively emits a debug information entry.
1666 void DwarfDebug::emitDIE(DIE &Die) {
1667 // Get the abbreviation for this DIE.
1668 const DIEAbbrev &Abbrev = Die.getAbbrev();
1670 // Emit the code (index) for the abbreviation.
1671 if (Asm->isVerbose())
1672 Asm->OutStreamer.AddComment("Abbrev [" + Twine(Abbrev.getNumber()) +
1673 "] 0x" + Twine::utohexstr(Die.getOffset()) +
1674 ":0x" + Twine::utohexstr(Die.getSize()) + " " +
1675 dwarf::TagString(Abbrev.getTag()));
1676 Asm->EmitULEB128(Abbrev.getNumber());
1678 const SmallVectorImpl<DIEValue *> &Values = Die.getValues();
1679 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
1681 // Emit the DIE attribute values.
1682 for (unsigned i = 0, N = Values.size(); i < N; ++i) {
1683 dwarf::Attribute Attr = AbbrevData[i].getAttribute();
1684 dwarf::Form Form = AbbrevData[i].getForm();
1685 assert(Form && "Too many attributes for DIE (check abbreviation)");
1687 if (Asm->isVerbose()) {
1688 Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr));
1689 if (Attr == dwarf::DW_AT_accessibility)
1690 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(
1691 cast<DIEInteger>(Values[i])->getValue()));
1694 // Emit an attribute using the defined form.
1695 Values[i]->EmitValue(Asm, Form);
1698 // Emit the DIE children if any.
1699 if (Abbrev.hasChildren()) {
1700 for (auto &Child : Die.getChildren())
1703 Asm->OutStreamer.AddComment("End Of Children Mark");
1708 // Emit the debug info section.
1709 void DwarfDebug::emitDebugInfo() {
1710 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1712 Holder.emitUnits(this, DwarfAbbrevSectionSym);
1715 // Emit the abbreviation section.
1716 void DwarfDebug::emitAbbreviations() {
1717 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1719 Holder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection());
1722 // Emit the last address of the section and the end of the line matrix.
1723 void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) {
1724 // Define last address of section.
1725 Asm->OutStreamer.AddComment("Extended Op");
1728 Asm->OutStreamer.AddComment("Op size");
1729 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1);
1730 Asm->OutStreamer.AddComment("DW_LNE_set_address");
1731 Asm->EmitInt8(dwarf::DW_LNE_set_address);
1733 Asm->OutStreamer.AddComment("Section end label");
1735 Asm->OutStreamer.EmitSymbolValue(
1736 Asm->GetTempSymbol("section_end", SectionEnd),
1737 Asm->getDataLayout().getPointerSize());
1739 // Mark end of matrix.
1740 Asm->OutStreamer.AddComment("DW_LNE_end_sequence");
1746 // Emit visible names into a hashed accelerator table section.
1747 void DwarfDebug::emitAccelNames() {
1748 AccelNames.FinalizeTable(Asm, "Names");
1749 Asm->OutStreamer.SwitchSection(
1750 Asm->getObjFileLowering().getDwarfAccelNamesSection());
1751 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin");
1752 Asm->OutStreamer.EmitLabel(SectionBegin);
1754 // Emit the full data.
1755 AccelNames.Emit(Asm, SectionBegin, &InfoHolder);
1758 // Emit objective C classes and categories into a hashed accelerator table
1760 void DwarfDebug::emitAccelObjC() {
1761 AccelObjC.FinalizeTable(Asm, "ObjC");
1762 Asm->OutStreamer.SwitchSection(
1763 Asm->getObjFileLowering().getDwarfAccelObjCSection());
1764 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin");
1765 Asm->OutStreamer.EmitLabel(SectionBegin);
1767 // Emit the full data.
1768 AccelObjC.Emit(Asm, SectionBegin, &InfoHolder);
1771 // Emit namespace dies into a hashed accelerator table.
1772 void DwarfDebug::emitAccelNamespaces() {
1773 AccelNamespace.FinalizeTable(Asm, "namespac");
1774 Asm->OutStreamer.SwitchSection(
1775 Asm->getObjFileLowering().getDwarfAccelNamespaceSection());
1776 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin");
1777 Asm->OutStreamer.EmitLabel(SectionBegin);
1779 // Emit the full data.
1780 AccelNamespace.Emit(Asm, SectionBegin, &InfoHolder);
1783 // Emit type dies into a hashed accelerator table.
1784 void DwarfDebug::emitAccelTypes() {
1786 AccelTypes.FinalizeTable(Asm, "types");
1787 Asm->OutStreamer.SwitchSection(
1788 Asm->getObjFileLowering().getDwarfAccelTypesSection());
1789 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin");
1790 Asm->OutStreamer.EmitLabel(SectionBegin);
1792 // Emit the full data.
1793 AccelTypes.Emit(Asm, SectionBegin, &InfoHolder);
1796 // Public name handling.
1797 // The format for the various pubnames:
1799 // dwarf pubnames - offset/name pairs where the offset is the offset into the CU
1800 // for the DIE that is named.
1802 // gnu pubnames - offset/index value/name tuples where the offset is the offset
1803 // into the CU and the index value is computed according to the type of value
1804 // for the DIE that is named.
1806 // For type units the offset is the offset of the skeleton DIE. For split dwarf
1807 // it's the offset within the debug_info/debug_types dwo section, however, the
1808 // reference in the pubname header doesn't change.
1810 /// computeIndexValue - Compute the gdb index value for the DIE and CU.
1811 static dwarf::PubIndexEntryDescriptor computeIndexValue(DwarfUnit *CU,
1813 dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC;
1815 // We could have a specification DIE that has our most of our knowledge,
1816 // look for that now.
1817 DIEValue *SpecVal = Die->findAttribute(dwarf::DW_AT_specification);
1819 DIE &SpecDIE = cast<DIEEntry>(SpecVal)->getEntry();
1820 if (SpecDIE.findAttribute(dwarf::DW_AT_external))
1821 Linkage = dwarf::GIEL_EXTERNAL;
1822 } else if (Die->findAttribute(dwarf::DW_AT_external))
1823 Linkage = dwarf::GIEL_EXTERNAL;
1825 switch (Die->getTag()) {
1826 case dwarf::DW_TAG_class_type:
1827 case dwarf::DW_TAG_structure_type:
1828 case dwarf::DW_TAG_union_type:
1829 case dwarf::DW_TAG_enumeration_type:
1830 return dwarf::PubIndexEntryDescriptor(
1831 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus
1832 ? dwarf::GIEL_STATIC
1833 : dwarf::GIEL_EXTERNAL);
1834 case dwarf::DW_TAG_typedef:
1835 case dwarf::DW_TAG_base_type:
1836 case dwarf::DW_TAG_subrange_type:
1837 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC);
1838 case dwarf::DW_TAG_namespace:
1839 return dwarf::GIEK_TYPE;
1840 case dwarf::DW_TAG_subprogram:
1841 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage);
1842 case dwarf::DW_TAG_constant:
1843 case dwarf::DW_TAG_variable:
1844 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage);
1845 case dwarf::DW_TAG_enumerator:
1846 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE,
1847 dwarf::GIEL_STATIC);
1849 return dwarf::GIEK_NONE;
1853 /// emitDebugPubNames - Emit visible names into a debug pubnames section.
1855 void DwarfDebug::emitDebugPubNames(bool GnuStyle) {
1856 const MCSection *PSec =
1857 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection()
1858 : Asm->getObjFileLowering().getDwarfPubNamesSection();
1860 emitDebugPubSection(GnuStyle, PSec, "Names", &DwarfUnit::getGlobalNames);
1863 void DwarfDebug::emitDebugPubSection(
1864 bool GnuStyle, const MCSection *PSec, StringRef Name,
1865 const StringMap<const DIE *> &(DwarfUnit::*Accessor)() const) {
1866 for (const auto &NU : CUMap) {
1867 DwarfCompileUnit *TheU = NU.second;
1869 const auto &Globals = (TheU->*Accessor)();
1871 if (Globals.empty())
1874 if (auto Skeleton = static_cast<DwarfCompileUnit *>(TheU->getSkeleton()))
1876 unsigned ID = TheU->getUniqueID();
1878 // Start the dwarf pubnames section.
1879 Asm->OutStreamer.SwitchSection(PSec);
1882 Asm->OutStreamer.AddComment("Length of Public " + Name + " Info");
1883 MCSymbol *BeginLabel = Asm->GetTempSymbol("pub" + Name + "_begin", ID);
1884 MCSymbol *EndLabel = Asm->GetTempSymbol("pub" + Name + "_end", ID);
1885 Asm->EmitLabelDifference(EndLabel, BeginLabel, 4);
1887 Asm->OutStreamer.EmitLabel(BeginLabel);
1889 Asm->OutStreamer.AddComment("DWARF Version");
1890 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION);
1892 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info");
1893 Asm->EmitSectionOffset(TheU->getLabelBegin(), TheU->getSectionSym());
1895 Asm->OutStreamer.AddComment("Compilation Unit Length");
1896 Asm->EmitLabelDifference(TheU->getLabelEnd(), TheU->getLabelBegin(), 4);
1898 // Emit the pubnames for this compilation unit.
1899 for (const auto &GI : Globals) {
1900 const char *Name = GI.getKeyData();
1901 const DIE *Entity = GI.second;
1903 Asm->OutStreamer.AddComment("DIE offset");
1904 Asm->EmitInt32(Entity->getOffset());
1907 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheU, Entity);
1908 Asm->OutStreamer.AddComment(
1909 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " +
1910 dwarf::GDBIndexEntryLinkageString(Desc.Linkage));
1911 Asm->EmitInt8(Desc.toBits());
1914 Asm->OutStreamer.AddComment("External Name");
1915 Asm->OutStreamer.EmitBytes(StringRef(Name, GI.getKeyLength() + 1));
1918 Asm->OutStreamer.AddComment("End Mark");
1920 Asm->OutStreamer.EmitLabel(EndLabel);
1924 void DwarfDebug::emitDebugPubTypes(bool GnuStyle) {
1925 const MCSection *PSec =
1926 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection()
1927 : Asm->getObjFileLowering().getDwarfPubTypesSection();
1929 emitDebugPubSection(GnuStyle, PSec, "Types", &DwarfUnit::getGlobalTypes);
1932 // Emit visible names into a debug str section.
1933 void DwarfDebug::emitDebugStr() {
1934 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1935 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection());
1938 void DwarfDebug::emitDebugLocEntry(ByteStreamer &Streamer,
1939 const DebugLocEntry &Entry) {
1940 assert(Entry.getValues().size() == 1 &&
1941 "multi-value entries are not supported yet.");
1942 const DebugLocEntry::Value Value = Entry.getValues()[0];
1943 DIVariable DV(Value.getVariable());
1944 if (Value.isInt()) {
1945 DIBasicType BTy(resolve(DV.getType()));
1946 if (BTy.Verify() && (BTy.getEncoding() == dwarf::DW_ATE_signed ||
1947 BTy.getEncoding() == dwarf::DW_ATE_signed_char)) {
1948 Streamer.EmitInt8(dwarf::DW_OP_consts, "DW_OP_consts");
1949 Streamer.EmitSLEB128(Value.getInt());
1951 Streamer.EmitInt8(dwarf::DW_OP_constu, "DW_OP_constu");
1952 Streamer.EmitULEB128(Value.getInt());
1954 } else if (Value.isLocation()) {
1955 MachineLocation Loc = Value.getLoc();
1956 if (!DV.hasComplexAddress())
1958 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
1960 // Complex address entry.
1961 unsigned N = DV.getNumAddrElements();
1963 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) {
1964 if (Loc.getOffset()) {
1966 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
1967 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
1968 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
1969 Streamer.EmitSLEB128(DV.getAddrElement(1));
1971 // If first address element is OpPlus then emit
1972 // DW_OP_breg + Offset instead of DW_OP_reg + Offset.
1973 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1));
1974 Asm->EmitDwarfRegOp(Streamer, TLoc, DV.isIndirect());
1978 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
1981 // Emit remaining complex address elements.
1982 for (; i < N; ++i) {
1983 uint64_t Element = DV.getAddrElement(i);
1984 if (Element == DIBuilder::OpPlus) {
1985 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
1986 Streamer.EmitULEB128(DV.getAddrElement(++i));
1987 } else if (Element == DIBuilder::OpDeref) {
1989 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
1991 llvm_unreachable("unknown Opcode found in complex address");
1995 // else ... ignore constant fp. There is not any good way to
1996 // to represent them here in dwarf.
2000 void DwarfDebug::emitDebugLocEntryLocation(const DebugLocEntry &Entry) {
2001 Asm->OutStreamer.AddComment("Loc expr size");
2002 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol();
2003 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol();
2004 Asm->EmitLabelDifference(end, begin, 2);
2005 Asm->OutStreamer.EmitLabel(begin);
2007 APByteStreamer Streamer(*Asm);
2008 emitDebugLocEntry(Streamer, Entry);
2010 Asm->OutStreamer.EmitLabel(end);
2013 // Emit locations into the debug loc section.
2014 void DwarfDebug::emitDebugLoc() {
2015 // Start the dwarf loc section.
2016 Asm->OutStreamer.SwitchSection(
2017 Asm->getObjFileLowering().getDwarfLocSection());
2018 unsigned char Size = Asm->getDataLayout().getPointerSize();
2019 for (const auto &DebugLoc : DotDebugLocEntries) {
2020 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2021 for (const auto &Entry : DebugLoc.List) {
2022 // Set up the range. This range is relative to the entry point of the
2023 // compile unit. This is a hard coded 0 for low_pc when we're emitting
2024 // ranges, or the DW_AT_low_pc on the compile unit otherwise.
2025 const DwarfCompileUnit *CU = Entry.getCU();
2026 if (CU->getRanges().size() == 1) {
2027 // Grab the begin symbol from the first range as our base.
2028 const MCSymbol *Base = CU->getRanges()[0].getStart();
2029 Asm->EmitLabelDifference(Entry.getBeginSym(), Base, Size);
2030 Asm->EmitLabelDifference(Entry.getEndSym(), Base, Size);
2032 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size);
2033 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size);
2036 emitDebugLocEntryLocation(Entry);
2038 Asm->OutStreamer.EmitIntValue(0, Size);
2039 Asm->OutStreamer.EmitIntValue(0, Size);
2043 void DwarfDebug::emitDebugLocDWO() {
2044 Asm->OutStreamer.SwitchSection(
2045 Asm->getObjFileLowering().getDwarfLocDWOSection());
2046 for (const auto &DebugLoc : DotDebugLocEntries) {
2047 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2048 for (const auto &Entry : DebugLoc.List) {
2049 // Just always use start_length for now - at least that's one address
2050 // rather than two. We could get fancier and try to, say, reuse an
2051 // address we know we've emitted elsewhere (the start of the function?
2052 // The start of the CU or CU subrange that encloses this range?)
2053 Asm->EmitInt8(dwarf::DW_LLE_start_length_entry);
2054 unsigned idx = AddrPool.getIndex(Entry.getBeginSym());
2055 Asm->EmitULEB128(idx);
2056 Asm->EmitLabelDifference(Entry.getEndSym(), Entry.getBeginSym(), 4);
2058 emitDebugLocEntryLocation(Entry);
2060 Asm->EmitInt8(dwarf::DW_LLE_end_of_list_entry);
2065 const MCSymbol *Start, *End;
2068 // Emit a debug aranges section, containing a CU lookup for any
2069 // address we can tie back to a CU.
2070 void DwarfDebug::emitDebugARanges() {
2071 // Start the dwarf aranges section.
2072 Asm->OutStreamer.SwitchSection(
2073 Asm->getObjFileLowering().getDwarfARangesSection());
2075 typedef DenseMap<DwarfCompileUnit *, std::vector<ArangeSpan>> SpansType;
2079 // Build a list of sections used.
2080 std::vector<const MCSection *> Sections;
2081 for (const auto &it : SectionMap) {
2082 const MCSection *Section = it.first;
2083 Sections.push_back(Section);
2086 // Sort the sections into order.
2087 // This is only done to ensure consistent output order across different runs.
2088 std::sort(Sections.begin(), Sections.end(), SectionSort);
2090 // Build a set of address spans, sorted by CU.
2091 for (const MCSection *Section : Sections) {
2092 SmallVector<SymbolCU, 8> &List = SectionMap[Section];
2093 if (List.size() < 2)
2096 // Sort the symbols by offset within the section.
2097 std::sort(List.begin(), List.end(),
2098 [&](const SymbolCU &A, const SymbolCU &B) {
2099 unsigned IA = A.Sym ? Asm->OutStreamer.GetSymbolOrder(A.Sym) : 0;
2100 unsigned IB = B.Sym ? Asm->OutStreamer.GetSymbolOrder(B.Sym) : 0;
2102 // Symbols with no order assigned should be placed at the end.
2103 // (e.g. section end labels)
2111 // If we have no section (e.g. common), just write out
2112 // individual spans for each symbol.
2114 for (const SymbolCU &Cur : List) {
2116 Span.Start = Cur.Sym;
2119 Spans[Cur.CU].push_back(Span);
2122 // Build spans between each label.
2123 const MCSymbol *StartSym = List[0].Sym;
2124 for (size_t n = 1, e = List.size(); n < e; n++) {
2125 const SymbolCU &Prev = List[n - 1];
2126 const SymbolCU &Cur = List[n];
2128 // Try and build the longest span we can within the same CU.
2129 if (Cur.CU != Prev.CU) {
2131 Span.Start = StartSym;
2133 Spans[Prev.CU].push_back(Span);
2140 unsigned PtrSize = Asm->getDataLayout().getPointerSize();
2142 // Build a list of CUs used.
2143 std::vector<DwarfCompileUnit *> CUs;
2144 for (const auto &it : Spans) {
2145 DwarfCompileUnit *CU = it.first;
2149 // Sort the CU list (again, to ensure consistent output order).
2150 std::sort(CUs.begin(), CUs.end(), [](const DwarfUnit *A, const DwarfUnit *B) {
2151 return A->getUniqueID() < B->getUniqueID();
2154 // Emit an arange table for each CU we used.
2155 for (DwarfCompileUnit *CU : CUs) {
2156 std::vector<ArangeSpan> &List = Spans[CU];
2158 // Emit size of content not including length itself.
2159 unsigned ContentSize =
2160 sizeof(int16_t) + // DWARF ARange version number
2161 sizeof(int32_t) + // Offset of CU in the .debug_info section
2162 sizeof(int8_t) + // Pointer Size (in bytes)
2163 sizeof(int8_t); // Segment Size (in bytes)
2165 unsigned TupleSize = PtrSize * 2;
2167 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple.
2169 OffsetToAlignment(sizeof(int32_t) + ContentSize, TupleSize);
2171 ContentSize += Padding;
2172 ContentSize += (List.size() + 1) * TupleSize;
2174 // For each compile unit, write the list of spans it covers.
2175 Asm->OutStreamer.AddComment("Length of ARange Set");
2176 Asm->EmitInt32(ContentSize);
2177 Asm->OutStreamer.AddComment("DWARF Arange version number");
2178 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION);
2179 Asm->OutStreamer.AddComment("Offset Into Debug Info Section");
2180 Asm->EmitSectionOffset(CU->getLocalLabelBegin(), CU->getLocalSectionSym());
2181 Asm->OutStreamer.AddComment("Address Size (in bytes)");
2182 Asm->EmitInt8(PtrSize);
2183 Asm->OutStreamer.AddComment("Segment Size (in bytes)");
2186 Asm->OutStreamer.EmitFill(Padding, 0xff);
2188 for (const ArangeSpan &Span : List) {
2189 Asm->EmitLabelReference(Span.Start, PtrSize);
2191 // Calculate the size as being from the span start to it's end.
2193 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize);
2195 // For symbols without an end marker (e.g. common), we
2196 // write a single arange entry containing just that one symbol.
2197 uint64_t Size = SymSize[Span.Start];
2201 Asm->OutStreamer.EmitIntValue(Size, PtrSize);
2205 Asm->OutStreamer.AddComment("ARange terminator");
2206 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2207 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2211 // Emit visible names into a debug ranges section.
2212 void DwarfDebug::emitDebugRanges() {
2213 // Start the dwarf ranges section.
2214 Asm->OutStreamer.SwitchSection(
2215 Asm->getObjFileLowering().getDwarfRangesSection());
2217 // Size for our labels.
2218 unsigned char Size = Asm->getDataLayout().getPointerSize();
2220 // Grab the specific ranges for the compile units in the module.
2221 for (const auto &I : CUMap) {
2222 DwarfCompileUnit *TheCU = I.second;
2224 // Iterate over the misc ranges for the compile units in the module.
2225 for (const RangeSpanList &List : TheCU->getRangeLists()) {
2226 // Emit our symbol so we can find the beginning of the range.
2227 Asm->OutStreamer.EmitLabel(List.getSym());
2229 for (const RangeSpan &Range : List.getRanges()) {
2230 const MCSymbol *Begin = Range.getStart();
2231 const MCSymbol *End = Range.getEnd();
2232 assert(Begin && "Range without a begin symbol?");
2233 assert(End && "Range without an end symbol?");
2234 if (TheCU->getRanges().size() == 1) {
2235 // Grab the begin symbol from the first range as our base.
2236 const MCSymbol *Base = TheCU->getRanges()[0].getStart();
2237 Asm->EmitLabelDifference(Begin, Base, Size);
2238 Asm->EmitLabelDifference(End, Base, Size);
2240 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2241 Asm->OutStreamer.EmitSymbolValue(End, Size);
2245 // And terminate the list with two 0 values.
2246 Asm->OutStreamer.EmitIntValue(0, Size);
2247 Asm->OutStreamer.EmitIntValue(0, Size);
2250 // Now emit a range for the CU itself.
2251 if (TheCU->getRanges().size() > 1) {
2252 Asm->OutStreamer.EmitLabel(
2253 Asm->GetTempSymbol("cu_ranges", TheCU->getUniqueID()));
2254 for (const RangeSpan &Range : TheCU->getRanges()) {
2255 const MCSymbol *Begin = Range.getStart();
2256 const MCSymbol *End = Range.getEnd();
2257 assert(Begin && "Range without a begin symbol?");
2258 assert(End && "Range without an end symbol?");
2259 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2260 Asm->OutStreamer.EmitSymbolValue(End, Size);
2262 // And terminate the list with two 0 values.
2263 Asm->OutStreamer.EmitIntValue(0, Size);
2264 Asm->OutStreamer.EmitIntValue(0, Size);
2269 // DWARF5 Experimental Separate Dwarf emitters.
2271 void DwarfDebug::initSkeletonUnit(const DwarfUnit &U, DIE &Die,
2272 std::unique_ptr<DwarfUnit> NewU) {
2273 NewU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name,
2274 U.getCUNode().getSplitDebugFilename());
2276 if (!CompilationDir.empty())
2277 NewU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
2279 addGnuPubAttributes(*NewU, Die);
2281 SkeletonHolder.addUnit(std::move(NewU));
2284 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list,
2285 // DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id,
2286 // DW_AT_addr_base, DW_AT_ranges_base.
2287 DwarfCompileUnit &DwarfDebug::constructSkeletonCU(const DwarfCompileUnit &CU) {
2289 auto OwnedUnit = make_unique<DwarfCompileUnit>(
2290 CU.getUniqueID(), CU.getCUNode(), Asm, this, &SkeletonHolder);
2291 DwarfCompileUnit &NewCU = *OwnedUnit;
2292 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
2293 DwarfInfoSectionSym);
2295 NewCU.initStmtList(DwarfLineSectionSym);
2297 initSkeletonUnit(CU, NewCU.getUnitDie(), std::move(OwnedUnit));
2302 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_dwo_name,
2304 DwarfTypeUnit &DwarfDebug::constructSkeletonTU(DwarfTypeUnit &TU) {
2305 DwarfCompileUnit &CU = static_cast<DwarfCompileUnit &>(
2306 *SkeletonHolder.getUnits()[TU.getCU().getUniqueID()]);
2308 auto OwnedUnit = make_unique<DwarfTypeUnit>(TU.getUniqueID(), CU, Asm, this,
2310 DwarfTypeUnit &NewTU = *OwnedUnit;
2311 NewTU.setTypeSignature(TU.getTypeSignature());
2312 NewTU.setType(nullptr);
2314 Asm->getObjFileLowering().getDwarfTypesSection(TU.getTypeSignature()));
2316 initSkeletonUnit(TU, NewTU.getUnitDie(), std::move(OwnedUnit));
2320 // Emit the .debug_info.dwo section for separated dwarf. This contains the
2321 // compile units that would normally be in debug_info.
2322 void DwarfDebug::emitDebugInfoDWO() {
2323 assert(useSplitDwarf() && "No split dwarf debug info?");
2324 // Don't pass an abbrev symbol, using a constant zero instead so as not to
2325 // emit relocations into the dwo file.
2326 InfoHolder.emitUnits(this, /* AbbrevSymbol */ nullptr);
2329 // Emit the .debug_abbrev.dwo section for separated dwarf. This contains the
2330 // abbreviations for the .debug_info.dwo section.
2331 void DwarfDebug::emitDebugAbbrevDWO() {
2332 assert(useSplitDwarf() && "No split dwarf?");
2333 InfoHolder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection());
2336 void DwarfDebug::emitDebugLineDWO() {
2337 assert(useSplitDwarf() && "No split dwarf?");
2338 Asm->OutStreamer.SwitchSection(
2339 Asm->getObjFileLowering().getDwarfLineDWOSection());
2340 SplitTypeUnitFileTable.Emit(Asm->OutStreamer);
2343 // Emit the .debug_str.dwo section for separated dwarf. This contains the
2344 // string section and is identical in format to traditional .debug_str
2346 void DwarfDebug::emitDebugStrDWO() {
2347 assert(useSplitDwarf() && "No split dwarf?");
2348 const MCSection *OffSec =
2349 Asm->getObjFileLowering().getDwarfStrOffDWOSection();
2350 const MCSymbol *StrSym = DwarfStrSectionSym;
2351 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(),
2355 MCDwarfDwoLineTable *DwarfDebug::getDwoLineTable(const DwarfCompileUnit &CU) {
2356 if (!useSplitDwarf())
2359 SplitTypeUnitFileTable.setCompilationDir(CU.getCUNode().getDirectory());
2360 return &SplitTypeUnitFileTable;
2363 static uint64_t makeTypeSignature(StringRef Identifier) {
2365 Hash.update(Identifier);
2366 // ... take the least significant 8 bytes and return those. Our MD5
2367 // implementation always returns its results in little endian, swap bytes
2369 MD5::MD5Result Result;
2371 return *reinterpret_cast<support::ulittle64_t *>(Result + 8);
2374 void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU,
2375 StringRef Identifier, DIE &RefDie,
2376 DICompositeType CTy) {
2377 // Fast path if we're building some type units and one has already used the
2378 // address pool we know we're going to throw away all this work anyway, so
2379 // don't bother building dependent types.
2380 if (!TypeUnitsUnderConstruction.empty() && AddrPool.hasBeenUsed())
2383 const DwarfTypeUnit *&TU = DwarfTypeUnits[CTy];
2385 CU.addDIETypeSignature(RefDie, *TU);
2389 bool TopLevelType = TypeUnitsUnderConstruction.empty();
2390 AddrPool.resetUsedFlag();
2393 make_unique<DwarfTypeUnit>(InfoHolder.getUnits().size(), CU, Asm, this,
2394 &InfoHolder, getDwoLineTable(CU));
2395 DwarfTypeUnit &NewTU = *OwnedUnit;
2396 DIE &UnitDie = NewTU.getUnitDie();
2398 TypeUnitsUnderConstruction.push_back(
2399 std::make_pair(std::move(OwnedUnit), CTy));
2401 NewTU.addUInt(UnitDie, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
2404 uint64_t Signature = makeTypeSignature(Identifier);
2405 NewTU.setTypeSignature(Signature);
2407 if (!useSplitDwarf())
2408 CU.applyStmtList(UnitDie);
2410 // FIXME: Skip using COMDAT groups for type units in the .dwo file once tools
2411 // such as DWP ( http://gcc.gnu.org/wiki/DebugFissionDWP ) can cope with it.
2414 ? Asm->getObjFileLowering().getDwarfTypesDWOSection(Signature)
2415 : Asm->getObjFileLowering().getDwarfTypesSection(Signature));
2417 NewTU.setType(NewTU.createTypeDIE(CTy));
2420 auto TypeUnitsToAdd = std::move(TypeUnitsUnderConstruction);
2421 TypeUnitsUnderConstruction.clear();
2423 // Types referencing entries in the address table cannot be placed in type
2425 if (AddrPool.hasBeenUsed()) {
2427 // Remove all the types built while building this type.
2428 // This is pessimistic as some of these types might not be dependent on
2429 // the type that used an address.
2430 for (const auto &TU : TypeUnitsToAdd)
2431 DwarfTypeUnits.erase(TU.second);
2433 // Construct this type in the CU directly.
2434 // This is inefficient because all the dependent types will be rebuilt
2435 // from scratch, including building them in type units, discovering that
2436 // they depend on addresses, throwing them out and rebuilding them.
2437 CU.constructTypeDIE(RefDie, CTy);
2441 // If the type wasn't dependent on fission addresses, finish adding the type
2442 // and all its dependent types.
2443 for (auto &TU : TypeUnitsToAdd) {
2444 if (useSplitDwarf())
2445 TU.first->setSkeleton(constructSkeletonTU(*TU.first));
2446 InfoHolder.addUnit(std::move(TU.first));
2449 CU.addDIETypeSignature(RefDie, NewTU);
2452 void DwarfDebug::attachLowHighPC(DwarfCompileUnit &Unit, DIE &D,
2453 MCSymbol *Begin, MCSymbol *End) {
2454 assert(Begin && "Begin label should not be null!");
2455 assert(End && "End label should not be null!");
2456 assert(Begin->isDefined() && "Invalid starting label");
2457 assert(End->isDefined() && "Invalid end label");
2459 Unit.addLabelAddress(D, dwarf::DW_AT_low_pc, Begin);
2460 if (DwarfVersion < 4)
2461 Unit.addLabelAddress(D, dwarf::DW_AT_high_pc, End);
2463 Unit.addLabelDelta(D, dwarf::DW_AT_high_pc, End, Begin);
2466 // Accelerator table mutators - add each name along with its companion
2467 // DIE to the proper table while ensuring that the name that we're going
2468 // to reference is in the string table. We do this since the names we
2469 // add may not only be identical to the names in the DIE.
2470 void DwarfDebug::addAccelName(StringRef Name, const DIE &Die) {
2471 if (!useDwarfAccelTables())
2473 AccelNames.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2477 void DwarfDebug::addAccelObjC(StringRef Name, const DIE &Die) {
2478 if (!useDwarfAccelTables())
2480 AccelObjC.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2484 void DwarfDebug::addAccelNamespace(StringRef Name, const DIE &Die) {
2485 if (!useDwarfAccelTables())
2487 AccelNamespace.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2491 void DwarfDebug::addAccelType(StringRef Name, const DIE &Die, char Flags) {
2492 if (!useDwarfAccelTables())
2494 AccelTypes.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),