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 const char *const DWARFGroupName = "DWARF Emission";
102 static const char *const DbgTimerName = "DWARF Debug Writer";
104 //===----------------------------------------------------------------------===//
106 /// resolve - Look in the DwarfDebug map for the MDNode that
107 /// corresponds to the reference.
108 template <typename T> T DbgVariable::resolve(DIRef<T> Ref) const {
109 return DD->resolve(Ref);
112 bool DbgVariable::isBlockByrefVariable() const {
113 assert(Var.isVariable() && "Invalid complex DbgVariable!");
114 return Var.isBlockByrefVariable(DD->getTypeIdentifierMap());
117 DIType DbgVariable::getType() const {
118 DIType Ty = Var.getType().resolve(DD->getTypeIdentifierMap());
119 // FIXME: isBlockByrefVariable should be reformulated in terms of complex
120 // addresses instead.
121 if (Var.isBlockByrefVariable(DD->getTypeIdentifierMap())) {
122 /* Byref variables, in Blocks, are declared by the programmer as
123 "SomeType VarName;", but the compiler creates a
124 __Block_byref_x_VarName struct, and gives the variable VarName
125 either the struct, or a pointer to the struct, as its type. This
126 is necessary for various behind-the-scenes things the compiler
127 needs to do with by-reference variables in blocks.
129 However, as far as the original *programmer* is concerned, the
130 variable should still have type 'SomeType', as originally declared.
132 The following function dives into the __Block_byref_x_VarName
133 struct to find the original type of the variable. This will be
134 passed back to the code generating the type for the Debug
135 Information Entry for the variable 'VarName'. 'VarName' will then
136 have the original type 'SomeType' in its debug information.
138 The original type 'SomeType' will be the type of the field named
139 'VarName' inside the __Block_byref_x_VarName struct.
141 NOTE: In order for this to not completely fail on the debugger
142 side, the Debug Information Entry for the variable VarName needs to
143 have a DW_AT_location that tells the debugger how to unwind through
144 the pointers and __Block_byref_x_VarName struct to find the actual
145 value of the variable. The function addBlockByrefType does this. */
147 uint16_t tag = Ty.getTag();
149 if (tag == dwarf::DW_TAG_pointer_type)
150 subType = resolve(DIDerivedType(Ty).getTypeDerivedFrom());
152 DIArray Elements = DICompositeType(subType).getTypeArray();
153 for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) {
154 DIDerivedType DT(Elements.getElement(i));
155 if (getName() == DT.getName())
156 return (resolve(DT.getTypeDerivedFrom()));
162 static LLVM_CONSTEXPR DwarfAccelTable::Atom TypeAtoms[] = {
163 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, dwarf::DW_FORM_data4),
164 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_tag, dwarf::DW_FORM_data2),
165 DwarfAccelTable::Atom(dwarf::DW_ATOM_type_flags, dwarf::DW_FORM_data1)};
167 DwarfDebug::DwarfDebug(AsmPrinter *A, Module *M)
168 : Asm(A), MMI(Asm->MMI), FirstCU(nullptr), PrevLabel(nullptr),
169 GlobalRangeCount(0), InfoHolder(A, "info_string", DIEValueAllocator),
170 UsedNonDefaultText(false),
171 SkeletonHolder(A, "skel_string", DIEValueAllocator),
172 AccelNames(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset,
173 dwarf::DW_FORM_data4)),
174 AccelObjC(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset,
175 dwarf::DW_FORM_data4)),
176 AccelNamespace(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset,
177 dwarf::DW_FORM_data4)),
178 AccelTypes(TypeAtoms) {
180 DwarfInfoSectionSym = DwarfAbbrevSectionSym = DwarfStrSectionSym = nullptr;
181 DwarfDebugRangeSectionSym = DwarfDebugLocSectionSym = nullptr;
182 DwarfLineSectionSym = nullptr;
183 DwarfAddrSectionSym = nullptr;
184 DwarfAbbrevDWOSectionSym = DwarfStrDWOSectionSym = nullptr;
185 FunctionBeginSym = FunctionEndSym = nullptr;
189 // Turn on accelerator tables for Darwin by default, pubnames by
190 // default for non-Darwin, and handle split dwarf.
191 bool IsDarwin = Triple(A->getTargetTriple()).isOSDarwin();
193 if (DwarfAccelTables == Default)
194 HasDwarfAccelTables = IsDarwin;
196 HasDwarfAccelTables = DwarfAccelTables == Enable;
198 if (SplitDwarf == Default)
199 HasSplitDwarf = false;
201 HasSplitDwarf = SplitDwarf == Enable;
203 if (DwarfPubSections == Default)
204 HasDwarfPubSections = !IsDarwin;
206 HasDwarfPubSections = DwarfPubSections == Enable;
208 unsigned DwarfVersionNumber = Asm->TM.Options.MCOptions.DwarfVersion;
209 DwarfVersion = DwarfVersionNumber ? DwarfVersionNumber
210 : MMI->getModule()->getDwarfVersion();
212 Asm->OutStreamer.getContext().setDwarfVersion(DwarfVersion);
215 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
220 // Define out of line so we don't have to include DwarfUnit.h in DwarfDebug.h.
221 DwarfDebug::~DwarfDebug() { }
223 // Switch to the specified MCSection and emit an assembler
224 // temporary label to it if SymbolStem is specified.
225 static MCSymbol *emitSectionSym(AsmPrinter *Asm, const MCSection *Section,
226 const char *SymbolStem = nullptr) {
227 Asm->OutStreamer.SwitchSection(Section);
231 MCSymbol *TmpSym = Asm->GetTempSymbol(SymbolStem);
232 Asm->OutStreamer.EmitLabel(TmpSym);
236 static bool isObjCClass(StringRef Name) {
237 return Name.startswith("+") || Name.startswith("-");
240 static bool hasObjCCategory(StringRef Name) {
241 if (!isObjCClass(Name))
244 return Name.find(") ") != StringRef::npos;
247 static void getObjCClassCategory(StringRef In, StringRef &Class,
248 StringRef &Category) {
249 if (!hasObjCCategory(In)) {
250 Class = In.slice(In.find('[') + 1, In.find(' '));
255 Class = In.slice(In.find('[') + 1, In.find('('));
256 Category = In.slice(In.find('[') + 1, In.find(' '));
260 static StringRef getObjCMethodName(StringRef In) {
261 return In.slice(In.find(' ') + 1, In.find(']'));
264 // Helper for sorting sections into a stable output order.
265 static bool SectionSort(const MCSection *A, const MCSection *B) {
266 std::string LA = (A ? A->getLabelBeginName() : "");
267 std::string LB = (B ? B->getLabelBeginName() : "");
271 // Add the various names to the Dwarf accelerator table names.
272 // TODO: Determine whether or not we should add names for programs
273 // that do not have a DW_AT_name or DW_AT_linkage_name field - this
274 // is only slightly different than the lookup of non-standard ObjC names.
275 void DwarfDebug::addSubprogramNames(DISubprogram SP, DIE &Die) {
276 if (!SP.isDefinition())
278 addAccelName(SP.getName(), Die);
280 // If the linkage name is different than the name, go ahead and output
281 // that as well into the name table.
282 if (SP.getLinkageName() != "" && SP.getName() != SP.getLinkageName())
283 addAccelName(SP.getLinkageName(), Die);
285 // If this is an Objective-C selector name add it to the ObjC accelerator
287 if (isObjCClass(SP.getName())) {
288 StringRef Class, Category;
289 getObjCClassCategory(SP.getName(), Class, Category);
290 addAccelObjC(Class, Die);
292 addAccelObjC(Category, Die);
293 // Also add the base method name to the name table.
294 addAccelName(getObjCMethodName(SP.getName()), Die);
298 /// isSubprogramContext - Return true if Context is either a subprogram
299 /// or another context nested inside a subprogram.
300 bool DwarfDebug::isSubprogramContext(const MDNode *Context) {
303 DIDescriptor D(Context);
304 if (D.isSubprogram())
307 return isSubprogramContext(resolve(DIType(Context).getContext()));
311 // Find DIE for the given subprogram and attach appropriate DW_AT_low_pc
312 // and DW_AT_high_pc attributes. If there are global variables in this
313 // scope then create and insert DIEs for these variables.
314 DIE &DwarfDebug::updateSubprogramScopeDIE(DwarfCompileUnit &SPCU,
316 DIE *SPDie = SPCU.getOrCreateSubprogramDIE(SP);
318 attachLowHighPC(SPCU, *SPDie, FunctionBeginSym, FunctionEndSym);
320 const TargetRegisterInfo *RI = Asm->TM.getRegisterInfo();
321 MachineLocation Location(RI->getFrameRegister(*Asm->MF));
322 SPCU.addAddress(*SPDie, dwarf::DW_AT_frame_base, Location);
324 // Add name to the name table, we do this here because we're guaranteed
325 // to have concrete versions of our DW_TAG_subprogram nodes.
326 addSubprogramNames(SP, *SPDie);
331 /// Check whether we should create a DIE for the given Scope, return true
332 /// if we don't create a DIE (the corresponding DIE is null).
333 bool DwarfDebug::isLexicalScopeDIENull(LexicalScope *Scope) {
334 if (Scope->isAbstractScope())
337 // We don't create a DIE if there is no Range.
338 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges();
342 if (Ranges.size() > 1)
345 // We don't create a DIE if we have a single Range and the end label
347 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin();
348 MCSymbol *End = getLabelAfterInsn(RI->second);
352 static void addSectionLabel(AsmPrinter &Asm, DwarfUnit &U, DIE &D,
353 dwarf::Attribute A, const MCSymbol *L,
354 const MCSymbol *Sec) {
355 if (Asm.MAI->doesDwarfUseRelocationsAcrossSections())
356 U.addSectionLabel(D, A, L);
358 U.addSectionDelta(D, A, L, Sec);
361 void DwarfDebug::addScopeRangeList(DwarfCompileUnit &TheCU, DIE &ScopeDIE,
362 const SmallVectorImpl<InsnRange> &Range) {
363 // Emit offset in .debug_range as a relocatable label. emitDIE will handle
364 // emitting it appropriately.
365 MCSymbol *RangeSym = Asm->GetTempSymbol("debug_ranges", GlobalRangeCount++);
367 // Under fission, ranges are specified by constant offsets relative to the
368 // CU's DW_AT_GNU_ranges_base.
370 TheCU.addSectionDelta(ScopeDIE, dwarf::DW_AT_ranges, RangeSym,
371 DwarfDebugRangeSectionSym);
373 addSectionLabel(*Asm, TheCU, ScopeDIE, dwarf::DW_AT_ranges, RangeSym,
374 DwarfDebugRangeSectionSym);
376 RangeSpanList List(RangeSym);
377 for (const InsnRange &R : Range) {
378 RangeSpan Span(getLabelBeforeInsn(R.first), getLabelAfterInsn(R.second));
379 List.addRange(std::move(Span));
382 // Add the range list to the set of ranges to be emitted.
383 TheCU.addRangeList(std::move(List));
386 void DwarfDebug::attachRangesOrLowHighPC(DwarfCompileUnit &TheCU, DIE &Die,
387 const SmallVectorImpl<InsnRange> &Ranges) {
388 assert(!Ranges.empty());
389 if (Ranges.size() == 1)
390 attachLowHighPC(TheCU, Die, getLabelBeforeInsn(Ranges.front().first),
391 getLabelAfterInsn(Ranges.front().second));
393 addScopeRangeList(TheCU, Die, Ranges);
396 // Construct new DW_TAG_lexical_block for this scope and attach
397 // DW_AT_low_pc/DW_AT_high_pc labels.
399 DwarfDebug::constructLexicalScopeDIE(DwarfCompileUnit &TheCU,
400 LexicalScope *Scope) {
401 if (isLexicalScopeDIENull(Scope))
404 auto ScopeDIE = make_unique<DIE>(dwarf::DW_TAG_lexical_block);
405 if (Scope->isAbstractScope())
408 attachRangesOrLowHighPC(TheCU, *ScopeDIE, Scope->getRanges());
413 // This scope represents inlined body of a function. Construct DIE to
414 // represent this concrete inlined copy of the function.
416 DwarfDebug::constructInlinedScopeDIE(DwarfCompileUnit &TheCU,
417 LexicalScope *Scope) {
418 assert(Scope->getScopeNode());
419 DIScope DS(Scope->getScopeNode());
420 DISubprogram InlinedSP = getDISubprogram(DS);
421 // Find the subprogram's DwarfCompileUnit in the SPMap in case the subprogram
422 // was inlined from another compile unit.
423 DIE *OriginDIE = AbstractSPDies[InlinedSP];
424 assert(OriginDIE && "Unable to find original DIE for an inlined subprogram.");
426 auto ScopeDIE = make_unique<DIE>(dwarf::DW_TAG_inlined_subroutine);
427 TheCU.addDIEEntry(*ScopeDIE, dwarf::DW_AT_abstract_origin, *OriginDIE);
429 attachRangesOrLowHighPC(TheCU, *ScopeDIE, Scope->getRanges());
431 InlinedSubprogramDIEs.insert(OriginDIE);
433 // Add the call site information to the DIE.
434 DILocation DL(Scope->getInlinedAt());
435 TheCU.addUInt(*ScopeDIE, dwarf::DW_AT_call_file, None,
436 TheCU.getOrCreateSourceID(DL.getFilename(), DL.getDirectory()));
437 TheCU.addUInt(*ScopeDIE, dwarf::DW_AT_call_line, None, DL.getLineNumber());
439 // Add name to the name table, we do this here because we're guaranteed
440 // to have concrete versions of our DW_TAG_inlined_subprogram nodes.
441 addSubprogramNames(InlinedSP, *ScopeDIE);
446 static std::unique_ptr<DIE> constructVariableDIE(DwarfCompileUnit &TheCU,
448 const LexicalScope &Scope,
449 DIE *&ObjectPointer) {
450 auto Var = TheCU.constructVariableDIE(DV, Scope.isAbstractScope());
451 if (DV.isObjectPointer())
452 ObjectPointer = Var.get();
456 DIE *DwarfDebug::createScopeChildrenDIE(
457 DwarfCompileUnit &TheCU, LexicalScope *Scope,
458 SmallVectorImpl<std::unique_ptr<DIE>> &Children) {
459 DIE *ObjectPointer = nullptr;
461 // Collect arguments for current function.
462 if (LScopes.isCurrentFunctionScope(Scope)) {
463 for (DbgVariable *ArgDV : CurrentFnArguments)
466 constructVariableDIE(TheCU, *ArgDV, *Scope, ObjectPointer));
468 // If this is a variadic function, add an unspecified parameter.
469 DISubprogram SP(Scope->getScopeNode());
470 DIArray FnArgs = SP.getType().getTypeArray();
471 if (FnArgs.getElement(FnArgs.getNumElements() - 1)
472 .isUnspecifiedParameter()) {
474 make_unique<DIE>(dwarf::DW_TAG_unspecified_parameters));
478 // Collect lexical scope children first.
479 for (DbgVariable *DV : ScopeVariables.lookup(Scope))
480 Children.push_back(constructVariableDIE(TheCU, *DV, *Scope, ObjectPointer));
482 for (LexicalScope *LS : Scope->getChildren())
483 if (std::unique_ptr<DIE> Nested = constructScopeDIE(TheCU, LS))
484 Children.push_back(std::move(Nested));
485 return ObjectPointer;
488 void DwarfDebug::createAndAddScopeChildren(DwarfCompileUnit &TheCU,
489 LexicalScope *Scope, DIE &ScopeDIE) {
490 // We create children when the scope DIE is not null.
491 SmallVector<std::unique_ptr<DIE>, 8> Children;
492 if (DIE *ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children))
493 TheCU.addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, *ObjectPointer);
496 for (auto &I : Children)
497 ScopeDIE.addChild(std::move(I));
500 void DwarfDebug::constructAbstractSubprogramScopeDIE(DwarfCompileUnit &TheCU,
501 LexicalScope *Scope) {
502 assert(Scope && Scope->getScopeNode());
503 assert(Scope->isAbstractScope());
504 assert(!Scope->getInlinedAt());
506 DISubprogram SP(Scope->getScopeNode());
508 ProcessedSPNodes.insert(SP);
510 DIE *&AbsDef = AbstractSPDies[SP];
514 // Find the subprogram's DwarfCompileUnit in the SPMap in case the subprogram
515 // was inlined from another compile unit.
516 DwarfCompileUnit &SPCU = *SPMap[SP];
519 // Some of this is duplicated from DwarfUnit::getOrCreateSubprogramDIE, with
520 // the important distinction that the DIDescriptor is not associated with the
521 // DIE (since the DIDescriptor will be associated with the concrete DIE, if
522 // any). It could be refactored to some common utility function.
523 if (DISubprogram SPDecl = SP.getFunctionDeclaration()) {
524 ContextDIE = &SPCU.getUnitDie();
525 SPCU.getOrCreateSubprogramDIE(SPDecl);
527 ContextDIE = SPCU.getOrCreateContextDIE(resolve(SP.getContext()));
529 // Passing null as the associated DIDescriptor because the abstract definition
530 // shouldn't be found by lookup.
531 AbsDef = &SPCU.createAndAddDIE(dwarf::DW_TAG_subprogram, *ContextDIE,
533 SPCU.applySubprogramAttributesToDefinition(SP, *AbsDef);
535 SPCU.addUInt(*AbsDef, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined);
536 createAndAddScopeChildren(SPCU, Scope, *AbsDef);
539 DIE &DwarfDebug::constructSubprogramScopeDIE(DwarfCompileUnit &TheCU,
540 LexicalScope *Scope) {
541 assert(Scope && Scope->getScopeNode());
542 assert(!Scope->getInlinedAt());
543 assert(!Scope->isAbstractScope());
544 DISubprogram Sub(Scope->getScopeNode());
546 assert(Sub.isSubprogram());
548 ProcessedSPNodes.insert(Sub);
550 DIE &ScopeDIE = updateSubprogramScopeDIE(TheCU, Sub);
552 createAndAddScopeChildren(TheCU, Scope, ScopeDIE);
557 // Construct a DIE for this scope.
558 std::unique_ptr<DIE> DwarfDebug::constructScopeDIE(DwarfCompileUnit &TheCU,
559 LexicalScope *Scope) {
560 if (!Scope || !Scope->getScopeNode())
563 DIScope DS(Scope->getScopeNode());
565 assert((Scope->getInlinedAt() || !DS.isSubprogram()) &&
566 "Only handle inlined subprograms here, use "
567 "constructSubprogramScopeDIE for non-inlined "
570 SmallVector<std::unique_ptr<DIE>, 8> Children;
572 // We try to create the scope DIE first, then the children DIEs. This will
573 // avoid creating un-used children then removing them later when we find out
574 // the scope DIE is null.
575 std::unique_ptr<DIE> ScopeDIE;
576 if (Scope->getParent() && DS.isSubprogram()) {
577 ScopeDIE = constructInlinedScopeDIE(TheCU, Scope);
580 // We create children when the scope DIE is not null.
581 createScopeChildrenDIE(TheCU, Scope, Children);
583 // Early exit when we know the scope DIE is going to be null.
584 if (isLexicalScopeDIENull(Scope))
587 // We create children here when we know the scope DIE is not going to be
588 // null and the children will be added to the scope DIE.
589 createScopeChildrenDIE(TheCU, Scope, Children);
591 // There is no need to emit empty lexical block DIE.
592 std::pair<ImportedEntityMap::const_iterator,
593 ImportedEntityMap::const_iterator> Range =
594 std::equal_range(ScopesWithImportedEntities.begin(),
595 ScopesWithImportedEntities.end(),
596 std::pair<const MDNode *, const MDNode *>(DS, nullptr),
598 if (Children.empty() && Range.first == Range.second)
600 ScopeDIE = constructLexicalScopeDIE(TheCU, Scope);
601 assert(ScopeDIE && "Scope DIE should not be null.");
602 for (ImportedEntityMap::const_iterator i = Range.first; i != Range.second;
604 constructImportedEntityDIE(TheCU, i->second, *ScopeDIE);
608 for (auto &I : Children)
609 ScopeDIE->addChild(std::move(I));
614 void DwarfDebug::addGnuPubAttributes(DwarfUnit &U, DIE &D) const {
615 if (!GenerateGnuPubSections)
618 U.addFlag(D, dwarf::DW_AT_GNU_pubnames);
621 // Create new DwarfCompileUnit for the given metadata node with tag
622 // DW_TAG_compile_unit.
623 DwarfCompileUnit &DwarfDebug::constructDwarfCompileUnit(DICompileUnit DIUnit) {
624 StringRef FN = DIUnit.getFilename();
625 CompilationDir = DIUnit.getDirectory();
627 auto OwnedUnit = make_unique<DwarfCompileUnit>(
628 InfoHolder.getUnits().size(), DIUnit, Asm, this, &InfoHolder);
629 DwarfCompileUnit &NewCU = *OwnedUnit;
630 DIE &Die = NewCU.getUnitDie();
631 InfoHolder.addUnit(std::move(OwnedUnit));
633 // LTO with assembly output shares a single line table amongst multiple CUs.
634 // To avoid the compilation directory being ambiguous, let the line table
635 // explicitly describe the directory of all files, never relying on the
636 // compilation directory.
637 if (!Asm->OutStreamer.hasRawTextSupport() || SingleCU)
638 Asm->OutStreamer.getContext().setMCLineTableCompilationDir(
639 NewCU.getUniqueID(), CompilationDir);
641 NewCU.addString(Die, dwarf::DW_AT_producer, DIUnit.getProducer());
642 NewCU.addUInt(Die, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
643 DIUnit.getLanguage());
644 NewCU.addString(Die, dwarf::DW_AT_name, FN);
646 if (!useSplitDwarf()) {
647 NewCU.initStmtList(DwarfLineSectionSym);
649 // If we're using split dwarf the compilation dir is going to be in the
650 // skeleton CU and so we don't need to duplicate it here.
651 if (!CompilationDir.empty())
652 NewCU.addString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
654 addGnuPubAttributes(NewCU, Die);
657 if (DIUnit.isOptimized())
658 NewCU.addFlag(Die, dwarf::DW_AT_APPLE_optimized);
660 StringRef Flags = DIUnit.getFlags();
662 NewCU.addString(Die, dwarf::DW_AT_APPLE_flags, Flags);
664 if (unsigned RVer = DIUnit.getRunTimeVersion())
665 NewCU.addUInt(Die, dwarf::DW_AT_APPLE_major_runtime_vers,
666 dwarf::DW_FORM_data1, RVer);
671 if (useSplitDwarf()) {
672 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoDWOSection(),
673 DwarfInfoDWOSectionSym);
674 NewCU.setSkeleton(constructSkeletonCU(NewCU));
676 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
677 DwarfInfoSectionSym);
679 CUMap.insert(std::make_pair(DIUnit, &NewCU));
680 CUDieMap.insert(std::make_pair(&Die, &NewCU));
684 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
686 DIImportedEntity Module(N);
687 assert(Module.Verify());
688 if (DIE *D = TheCU.getOrCreateContextDIE(Module.getContext()))
689 constructImportedEntityDIE(TheCU, Module, *D);
692 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
693 const MDNode *N, DIE &Context) {
694 DIImportedEntity Module(N);
695 assert(Module.Verify());
696 return constructImportedEntityDIE(TheCU, Module, Context);
699 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
700 const DIImportedEntity &Module,
702 assert(Module.Verify() &&
703 "Use one of the MDNode * overloads to handle invalid metadata");
704 DIE &IMDie = TheCU.createAndAddDIE(Module.getTag(), Context, Module);
706 DIDescriptor Entity = resolve(Module.getEntity());
707 if (Entity.isNameSpace())
708 EntityDie = TheCU.getOrCreateNameSpace(DINameSpace(Entity));
709 else if (Entity.isSubprogram())
710 EntityDie = TheCU.getOrCreateSubprogramDIE(DISubprogram(Entity));
711 else if (Entity.isType())
712 EntityDie = TheCU.getOrCreateTypeDIE(DIType(Entity));
714 EntityDie = TheCU.getDIE(Entity);
715 TheCU.addSourceLine(IMDie, Module.getLineNumber(),
716 Module.getContext().getFilename(),
717 Module.getContext().getDirectory());
718 TheCU.addDIEEntry(IMDie, dwarf::DW_AT_import, *EntityDie);
719 StringRef Name = Module.getName();
721 TheCU.addString(IMDie, dwarf::DW_AT_name, Name);
724 // Emit all Dwarf sections that should come prior to the content. Create
725 // global DIEs and emit initial debug info sections. This is invoked by
726 // the target AsmPrinter.
727 void DwarfDebug::beginModule() {
728 if (DisableDebugInfoPrinting)
731 const Module *M = MMI->getModule();
733 FunctionDIs = makeSubprogramMap(*M);
735 // If module has named metadata anchors then use them, otherwise scan the
736 // module using debug info finder to collect debug info.
737 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
740 TypeIdentifierMap = generateDITypeIdentifierMap(CU_Nodes);
742 // Emit initial sections so we can reference labels later.
745 SingleCU = CU_Nodes->getNumOperands() == 1;
747 for (MDNode *N : CU_Nodes->operands()) {
748 DICompileUnit CUNode(N);
749 DwarfCompileUnit &CU = constructDwarfCompileUnit(CUNode);
750 DIArray ImportedEntities = CUNode.getImportedEntities();
751 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
752 ScopesWithImportedEntities.push_back(std::make_pair(
753 DIImportedEntity(ImportedEntities.getElement(i)).getContext(),
754 ImportedEntities.getElement(i)));
755 std::sort(ScopesWithImportedEntities.begin(),
756 ScopesWithImportedEntities.end(), less_first());
757 DIArray GVs = CUNode.getGlobalVariables();
758 for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i)
759 CU.createGlobalVariableDIE(DIGlobalVariable(GVs.getElement(i)));
760 DIArray SPs = CUNode.getSubprograms();
761 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i)
762 SPMap.insert(std::make_pair(SPs.getElement(i), &CU));
763 DIArray EnumTypes = CUNode.getEnumTypes();
764 for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i)
765 CU.getOrCreateTypeDIE(EnumTypes.getElement(i));
766 DIArray RetainedTypes = CUNode.getRetainedTypes();
767 for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i) {
768 DIType Ty(RetainedTypes.getElement(i));
769 // The retained types array by design contains pointers to
770 // MDNodes rather than DIRefs. Unique them here.
771 DIType UniqueTy(resolve(Ty.getRef()));
772 CU.getOrCreateTypeDIE(UniqueTy);
774 // Emit imported_modules last so that the relevant context is already
776 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
777 constructImportedEntityDIE(CU, ImportedEntities.getElement(i));
780 // Tell MMI that we have debug info.
781 MMI->setDebugInfoAvailability(true);
783 // Prime section data.
784 SectionMap[Asm->getObjFileLowering().getTextSection()];
787 void DwarfDebug::finishVariableDefinitions() {
788 for (const auto &Var : ConcreteVariables) {
789 DIE *VariableDie = Var->getDIE();
790 // 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();
1043 // Emit DWO addresses.
1044 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 auto DI = FunctionDIs.find(MF->getFunction());
1420 if (DI == FunctionDIs.end())
1423 // Grab the lexical scopes for the function, if we don't have any of those
1424 // then we're not going to be able to do anything.
1425 LScopes.initialize(*MF);
1426 if (LScopes.empty())
1429 assert(DbgValues.empty() && "DbgValues map wasn't cleaned!");
1431 // Make sure that each lexical scope will have a begin/end label.
1432 identifyScopeMarkers();
1434 // Set DwarfDwarfCompileUnitID in MCContext to the Compile Unit this function
1435 // belongs to so that we add to the correct per-cu line table in the
1437 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1438 // FnScope->getScopeNode() and DI->second should represent the same function,
1439 // though they may not be the same MDNode due to inline functions merged in
1440 // LTO where the debug info metadata still differs (either due to distinct
1441 // written differences - two versions of a linkonce_odr function
1442 // written/copied into two separate files, or some sub-optimal metadata that
1443 // isn't structurally identical (see: file path/name info from clang, which
1444 // includes the directory of the cpp file being built, even when the file name
1445 // is absolute (such as an <> lookup header)))
1446 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1447 assert(TheCU && "Unable to find compile unit!");
1448 if (Asm->OutStreamer.hasRawTextSupport())
1449 // Use a single line table if we are generating assembly.
1450 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1452 Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID());
1454 // Emit a label for the function so that we have a beginning address.
1455 FunctionBeginSym = Asm->GetTempSymbol("func_begin", Asm->getFunctionNumber());
1456 // Assumes in correct section after the entry point.
1457 Asm->OutStreamer.EmitLabel(FunctionBeginSym);
1459 // Calculate history for local variables.
1460 calculateDbgValueHistory(MF, Asm->TM.getRegisterInfo(), DbgValues);
1462 // Request labels for the full history.
1463 for (const auto &I : DbgValues) {
1464 const auto &Ranges = I.second;
1468 // The first mention of a function argument gets the FunctionBeginSym
1469 // label, so arguments are visible when breaking at function entry.
1470 DIVariable DV(I.first);
1471 if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable &&
1472 getDISubprogram(DV.getContext()).describes(MF->getFunction()))
1473 LabelsBeforeInsn[Ranges.front().first] = FunctionBeginSym;
1475 for (const auto &Range : Ranges) {
1476 requestLabelBeforeInsn(Range.first);
1478 requestLabelAfterInsn(Range.second);
1482 PrevInstLoc = DebugLoc();
1483 PrevLabel = FunctionBeginSym;
1485 // Record beginning of function.
1486 PrologEndLoc = findPrologueEndLoc(MF);
1487 if (!PrologEndLoc.isUnknown()) {
1488 DebugLoc FnStartDL =
1489 PrologEndLoc.getFnDebugLoc(MF->getFunction()->getContext());
1491 FnStartDL.getLine(), FnStartDL.getCol(),
1492 FnStartDL.getScope(MF->getFunction()->getContext()),
1493 // We'd like to list the prologue as "not statements" but GDB behaves
1494 // poorly if we do that. Revisit this with caution/GDB (7.5+) testing.
1495 DWARF2_FLAG_IS_STMT);
1499 void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) {
1500 if (addCurrentFnArgument(Var, LS))
1502 SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS];
1503 DIVariable DV = Var->getVariable();
1504 // Variables with positive arg numbers are parameters.
1505 if (unsigned ArgNum = DV.getArgNumber()) {
1506 // Keep all parameters in order at the start of the variable list to ensure
1507 // function types are correct (no out-of-order parameters)
1509 // This could be improved by only doing it for optimized builds (unoptimized
1510 // builds have the right order to begin with), searching from the back (this
1511 // would catch the unoptimized case quickly), or doing a binary search
1512 // rather than linear search.
1513 SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin();
1514 while (I != Vars.end()) {
1515 unsigned CurNum = (*I)->getVariable().getArgNumber();
1516 // A local (non-parameter) variable has been found, insert immediately
1520 // A later indexed parameter has been found, insert immediately before it.
1521 if (CurNum > ArgNum)
1525 Vars.insert(I, Var);
1529 Vars.push_back(Var);
1532 // Gather and emit post-function debug information.
1533 void DwarfDebug::endFunction(const MachineFunction *MF) {
1534 // Every beginFunction(MF) call should be followed by an endFunction(MF) call,
1535 // though the beginFunction may not be called at all.
1536 // We should handle both cases.
1540 assert(CurFn == MF);
1541 assert(CurFn != nullptr);
1543 if (!MMI->hasDebugInfo() || LScopes.empty() ||
1544 !FunctionDIs.count(MF->getFunction())) {
1545 // If we don't have a lexical scope for this function then there will
1546 // be a hole in the range information. Keep note of this by setting the
1547 // previously used section to nullptr.
1548 PrevSection = nullptr;
1554 // Define end label for subprogram.
1555 FunctionEndSym = Asm->GetTempSymbol("func_end", Asm->getFunctionNumber());
1556 // Assumes in correct section after the entry point.
1557 Asm->OutStreamer.EmitLabel(FunctionEndSym);
1559 // Set DwarfDwarfCompileUnitID in MCContext to default value.
1560 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1562 SmallPtrSet<const MDNode *, 16> ProcessedVars;
1563 collectVariableInfo(ProcessedVars);
1565 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1566 DwarfCompileUnit &TheCU = *SPMap.lookup(FnScope->getScopeNode());
1568 // Construct abstract scopes.
1569 for (LexicalScope *AScope : LScopes.getAbstractScopesList()) {
1570 DISubprogram SP(AScope->getScopeNode());
1571 if (!SP.isSubprogram())
1573 // Collect info for variables that were optimized out.
1574 DIArray Variables = SP.getVariables();
1575 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1576 DIVariable DV(Variables.getElement(i));
1577 assert(DV && DV.isVariable());
1578 if (!ProcessedVars.insert(DV))
1580 ensureAbstractVariableIsCreated(DV, DV.getContext());
1582 constructAbstractSubprogramScopeDIE(TheCU, AScope);
1585 DIE &CurFnDIE = constructSubprogramScopeDIE(TheCU, FnScope);
1586 if (!CurFn->getTarget().Options.DisableFramePointerElim(*CurFn))
1587 TheCU.addFlag(CurFnDIE, dwarf::DW_AT_APPLE_omit_frame_ptr);
1589 // Add the range of this function to the list of ranges for the CU.
1590 RangeSpan Span(FunctionBeginSym, FunctionEndSym);
1591 TheCU.addRange(std::move(Span));
1592 PrevSection = Asm->getCurrentSection();
1596 // Ownership of DbgVariables is a bit subtle - ScopeVariables owns all the
1597 // DbgVariables except those that are also in AbstractVariables (since they
1598 // can be used cross-function)
1599 ScopeVariables.clear();
1600 CurrentFnArguments.clear();
1602 LabelsBeforeInsn.clear();
1603 LabelsAfterInsn.clear();
1604 PrevLabel = nullptr;
1608 // Register a source line with debug info. Returns the unique label that was
1609 // emitted and which provides correspondence to the source line list.
1610 void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S,
1615 unsigned Discriminator = 0;
1616 if (DIScope Scope = DIScope(S)) {
1617 assert(Scope.isScope());
1618 Fn = Scope.getFilename();
1619 Dir = Scope.getDirectory();
1620 if (Scope.isLexicalBlock())
1621 Discriminator = DILexicalBlock(S).getDiscriminator();
1623 unsigned CUID = Asm->OutStreamer.getContext().getDwarfCompileUnitID();
1624 Src = static_cast<DwarfCompileUnit &>(*InfoHolder.getUnits()[CUID])
1625 .getOrCreateSourceID(Fn, Dir);
1627 Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0,
1631 //===----------------------------------------------------------------------===//
1633 //===----------------------------------------------------------------------===//
1635 // Emit initial Dwarf sections with a label at the start of each one.
1636 void DwarfDebug::emitSectionLabels() {
1637 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
1639 // Dwarf sections base addresses.
1640 DwarfInfoSectionSym =
1641 emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info");
1642 if (useSplitDwarf())
1643 DwarfInfoDWOSectionSym =
1644 emitSectionSym(Asm, TLOF.getDwarfInfoDWOSection(), "section_info_dwo");
1645 DwarfAbbrevSectionSym =
1646 emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev");
1647 if (useSplitDwarf())
1648 DwarfAbbrevDWOSectionSym = emitSectionSym(
1649 Asm, TLOF.getDwarfAbbrevDWOSection(), "section_abbrev_dwo");
1650 if (GenerateARangeSection)
1651 emitSectionSym(Asm, TLOF.getDwarfARangesSection());
1653 DwarfLineSectionSym =
1654 emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line");
1655 if (GenerateGnuPubSections) {
1656 DwarfGnuPubNamesSectionSym =
1657 emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection());
1658 DwarfGnuPubTypesSectionSym =
1659 emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection());
1660 } else if (HasDwarfPubSections) {
1661 emitSectionSym(Asm, TLOF.getDwarfPubNamesSection());
1662 emitSectionSym(Asm, TLOF.getDwarfPubTypesSection());
1665 DwarfStrSectionSym =
1666 emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string");
1667 if (useSplitDwarf()) {
1668 DwarfStrDWOSectionSym =
1669 emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string");
1670 DwarfAddrSectionSym =
1671 emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec");
1672 DwarfDebugLocSectionSym =
1673 emitSectionSym(Asm, TLOF.getDwarfLocDWOSection(), "skel_loc");
1675 DwarfDebugLocSectionSym =
1676 emitSectionSym(Asm, TLOF.getDwarfLocSection(), "section_debug_loc");
1677 DwarfDebugRangeSectionSym =
1678 emitSectionSym(Asm, TLOF.getDwarfRangesSection(), "debug_range");
1681 // Recursively emits a debug information entry.
1682 void DwarfDebug::emitDIE(DIE &Die) {
1683 // Get the abbreviation for this DIE.
1684 const DIEAbbrev &Abbrev = Die.getAbbrev();
1686 // Emit the code (index) for the abbreviation.
1687 if (Asm->isVerbose())
1688 Asm->OutStreamer.AddComment("Abbrev [" + Twine(Abbrev.getNumber()) +
1689 "] 0x" + Twine::utohexstr(Die.getOffset()) +
1690 ":0x" + Twine::utohexstr(Die.getSize()) + " " +
1691 dwarf::TagString(Abbrev.getTag()));
1692 Asm->EmitULEB128(Abbrev.getNumber());
1694 const SmallVectorImpl<DIEValue *> &Values = Die.getValues();
1695 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
1697 // Emit the DIE attribute values.
1698 for (unsigned i = 0, N = Values.size(); i < N; ++i) {
1699 dwarf::Attribute Attr = AbbrevData[i].getAttribute();
1700 dwarf::Form Form = AbbrevData[i].getForm();
1701 assert(Form && "Too many attributes for DIE (check abbreviation)");
1703 if (Asm->isVerbose()) {
1704 Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr));
1705 if (Attr == dwarf::DW_AT_accessibility)
1706 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(
1707 cast<DIEInteger>(Values[i])->getValue()));
1710 // Emit an attribute using the defined form.
1711 Values[i]->EmitValue(Asm, Form);
1714 // Emit the DIE children if any.
1715 if (Abbrev.hasChildren()) {
1716 for (auto &Child : Die.getChildren())
1719 Asm->OutStreamer.AddComment("End Of Children Mark");
1724 // Emit the debug info section.
1725 void DwarfDebug::emitDebugInfo() {
1726 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1728 Holder.emitUnits(this, DwarfAbbrevSectionSym);
1731 // Emit the abbreviation section.
1732 void DwarfDebug::emitAbbreviations() {
1733 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1735 Holder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection());
1738 // Emit the last address of the section and the end of the line matrix.
1739 void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) {
1740 // Define last address of section.
1741 Asm->OutStreamer.AddComment("Extended Op");
1744 Asm->OutStreamer.AddComment("Op size");
1745 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1);
1746 Asm->OutStreamer.AddComment("DW_LNE_set_address");
1747 Asm->EmitInt8(dwarf::DW_LNE_set_address);
1749 Asm->OutStreamer.AddComment("Section end label");
1751 Asm->OutStreamer.EmitSymbolValue(
1752 Asm->GetTempSymbol("section_end", SectionEnd),
1753 Asm->getDataLayout().getPointerSize());
1755 // Mark end of matrix.
1756 Asm->OutStreamer.AddComment("DW_LNE_end_sequence");
1762 // Emit visible names into a hashed accelerator table section.
1763 void DwarfDebug::emitAccelNames() {
1764 AccelNames.FinalizeTable(Asm, "Names");
1765 Asm->OutStreamer.SwitchSection(
1766 Asm->getObjFileLowering().getDwarfAccelNamesSection());
1767 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin");
1768 Asm->OutStreamer.EmitLabel(SectionBegin);
1770 // Emit the full data.
1771 AccelNames.Emit(Asm, SectionBegin, &InfoHolder);
1774 // Emit objective C classes and categories into a hashed accelerator table
1776 void DwarfDebug::emitAccelObjC() {
1777 AccelObjC.FinalizeTable(Asm, "ObjC");
1778 Asm->OutStreamer.SwitchSection(
1779 Asm->getObjFileLowering().getDwarfAccelObjCSection());
1780 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin");
1781 Asm->OutStreamer.EmitLabel(SectionBegin);
1783 // Emit the full data.
1784 AccelObjC.Emit(Asm, SectionBegin, &InfoHolder);
1787 // Emit namespace dies into a hashed accelerator table.
1788 void DwarfDebug::emitAccelNamespaces() {
1789 AccelNamespace.FinalizeTable(Asm, "namespac");
1790 Asm->OutStreamer.SwitchSection(
1791 Asm->getObjFileLowering().getDwarfAccelNamespaceSection());
1792 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin");
1793 Asm->OutStreamer.EmitLabel(SectionBegin);
1795 // Emit the full data.
1796 AccelNamespace.Emit(Asm, SectionBegin, &InfoHolder);
1799 // Emit type dies into a hashed accelerator table.
1800 void DwarfDebug::emitAccelTypes() {
1802 AccelTypes.FinalizeTable(Asm, "types");
1803 Asm->OutStreamer.SwitchSection(
1804 Asm->getObjFileLowering().getDwarfAccelTypesSection());
1805 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin");
1806 Asm->OutStreamer.EmitLabel(SectionBegin);
1808 // Emit the full data.
1809 AccelTypes.Emit(Asm, SectionBegin, &InfoHolder);
1812 // Public name handling.
1813 // The format for the various pubnames:
1815 // dwarf pubnames - offset/name pairs where the offset is the offset into the CU
1816 // for the DIE that is named.
1818 // gnu pubnames - offset/index value/name tuples where the offset is the offset
1819 // into the CU and the index value is computed according to the type of value
1820 // for the DIE that is named.
1822 // For type units the offset is the offset of the skeleton DIE. For split dwarf
1823 // it's the offset within the debug_info/debug_types dwo section, however, the
1824 // reference in the pubname header doesn't change.
1826 /// computeIndexValue - Compute the gdb index value for the DIE and CU.
1827 static dwarf::PubIndexEntryDescriptor computeIndexValue(DwarfUnit *CU,
1829 dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC;
1831 // We could have a specification DIE that has our most of our knowledge,
1832 // look for that now.
1833 DIEValue *SpecVal = Die->findAttribute(dwarf::DW_AT_specification);
1835 DIE &SpecDIE = cast<DIEEntry>(SpecVal)->getEntry();
1836 if (SpecDIE.findAttribute(dwarf::DW_AT_external))
1837 Linkage = dwarf::GIEL_EXTERNAL;
1838 } else if (Die->findAttribute(dwarf::DW_AT_external))
1839 Linkage = dwarf::GIEL_EXTERNAL;
1841 switch (Die->getTag()) {
1842 case dwarf::DW_TAG_class_type:
1843 case dwarf::DW_TAG_structure_type:
1844 case dwarf::DW_TAG_union_type:
1845 case dwarf::DW_TAG_enumeration_type:
1846 return dwarf::PubIndexEntryDescriptor(
1847 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus
1848 ? dwarf::GIEL_STATIC
1849 : dwarf::GIEL_EXTERNAL);
1850 case dwarf::DW_TAG_typedef:
1851 case dwarf::DW_TAG_base_type:
1852 case dwarf::DW_TAG_subrange_type:
1853 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC);
1854 case dwarf::DW_TAG_namespace:
1855 return dwarf::GIEK_TYPE;
1856 case dwarf::DW_TAG_subprogram:
1857 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage);
1858 case dwarf::DW_TAG_constant:
1859 case dwarf::DW_TAG_variable:
1860 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage);
1861 case dwarf::DW_TAG_enumerator:
1862 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE,
1863 dwarf::GIEL_STATIC);
1865 return dwarf::GIEK_NONE;
1869 /// emitDebugPubNames - Emit visible names into a debug pubnames section.
1871 void DwarfDebug::emitDebugPubNames(bool GnuStyle) {
1872 const MCSection *PSec =
1873 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection()
1874 : Asm->getObjFileLowering().getDwarfPubNamesSection();
1876 emitDebugPubSection(GnuStyle, PSec, "Names", &DwarfUnit::getGlobalNames);
1879 void DwarfDebug::emitDebugPubSection(
1880 bool GnuStyle, const MCSection *PSec, StringRef Name,
1881 const StringMap<const DIE *> &(DwarfUnit::*Accessor)() const) {
1882 for (const auto &NU : CUMap) {
1883 DwarfCompileUnit *TheU = NU.second;
1885 const auto &Globals = (TheU->*Accessor)();
1887 if (Globals.empty())
1890 if (auto Skeleton = static_cast<DwarfCompileUnit *>(TheU->getSkeleton()))
1892 unsigned ID = TheU->getUniqueID();
1894 // Start the dwarf pubnames section.
1895 Asm->OutStreamer.SwitchSection(PSec);
1898 Asm->OutStreamer.AddComment("Length of Public " + Name + " Info");
1899 MCSymbol *BeginLabel = Asm->GetTempSymbol("pub" + Name + "_begin", ID);
1900 MCSymbol *EndLabel = Asm->GetTempSymbol("pub" + Name + "_end", ID);
1901 Asm->EmitLabelDifference(EndLabel, BeginLabel, 4);
1903 Asm->OutStreamer.EmitLabel(BeginLabel);
1905 Asm->OutStreamer.AddComment("DWARF Version");
1906 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION);
1908 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info");
1909 Asm->EmitSectionOffset(TheU->getLabelBegin(), TheU->getSectionSym());
1911 Asm->OutStreamer.AddComment("Compilation Unit Length");
1912 Asm->EmitLabelDifference(TheU->getLabelEnd(), TheU->getLabelBegin(), 4);
1914 // Emit the pubnames for this compilation unit.
1915 for (const auto &GI : Globals) {
1916 const char *Name = GI.getKeyData();
1917 const DIE *Entity = GI.second;
1919 Asm->OutStreamer.AddComment("DIE offset");
1920 Asm->EmitInt32(Entity->getOffset());
1923 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheU, Entity);
1924 Asm->OutStreamer.AddComment(
1925 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " +
1926 dwarf::GDBIndexEntryLinkageString(Desc.Linkage));
1927 Asm->EmitInt8(Desc.toBits());
1930 Asm->OutStreamer.AddComment("External Name");
1931 Asm->OutStreamer.EmitBytes(StringRef(Name, GI.getKeyLength() + 1));
1934 Asm->OutStreamer.AddComment("End Mark");
1936 Asm->OutStreamer.EmitLabel(EndLabel);
1940 void DwarfDebug::emitDebugPubTypes(bool GnuStyle) {
1941 const MCSection *PSec =
1942 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection()
1943 : Asm->getObjFileLowering().getDwarfPubTypesSection();
1945 emitDebugPubSection(GnuStyle, PSec, "Types", &DwarfUnit::getGlobalTypes);
1948 // Emit visible names into a debug str section.
1949 void DwarfDebug::emitDebugStr() {
1950 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1951 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection());
1954 void DwarfDebug::emitDebugLocEntry(ByteStreamer &Streamer,
1955 const DebugLocEntry &Entry) {
1956 assert(Entry.getValues().size() == 1 &&
1957 "multi-value entries are not supported yet.");
1958 const DebugLocEntry::Value Value = Entry.getValues()[0];
1959 DIVariable DV(Value.getVariable());
1960 if (Value.isInt()) {
1961 DIBasicType BTy(resolve(DV.getType()));
1962 if (BTy.Verify() && (BTy.getEncoding() == dwarf::DW_ATE_signed ||
1963 BTy.getEncoding() == dwarf::DW_ATE_signed_char)) {
1964 Streamer.EmitInt8(dwarf::DW_OP_consts, "DW_OP_consts");
1965 Streamer.EmitSLEB128(Value.getInt());
1967 Streamer.EmitInt8(dwarf::DW_OP_constu, "DW_OP_constu");
1968 Streamer.EmitULEB128(Value.getInt());
1970 } else if (Value.isLocation()) {
1971 MachineLocation Loc = Value.getLoc();
1972 if (!DV.hasComplexAddress())
1974 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
1976 // Complex address entry.
1977 unsigned N = DV.getNumAddrElements();
1979 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) {
1980 if (Loc.getOffset()) {
1982 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
1983 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
1984 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
1985 Streamer.EmitSLEB128(DV.getAddrElement(1));
1987 // If first address element is OpPlus then emit
1988 // DW_OP_breg + Offset instead of DW_OP_reg + Offset.
1989 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1));
1990 Asm->EmitDwarfRegOp(Streamer, TLoc, DV.isIndirect());
1994 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
1997 // Emit remaining complex address elements.
1998 for (; i < N; ++i) {
1999 uint64_t Element = DV.getAddrElement(i);
2000 if (Element == DIBuilder::OpPlus) {
2001 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
2002 Streamer.EmitULEB128(DV.getAddrElement(++i));
2003 } else if (Element == DIBuilder::OpDeref) {
2005 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
2007 llvm_unreachable("unknown Opcode found in complex address");
2011 // else ... ignore constant fp. There is not any good way to
2012 // to represent them here in dwarf.
2016 void DwarfDebug::emitDebugLocEntryLocation(const DebugLocEntry &Entry) {
2017 Asm->OutStreamer.AddComment("Loc expr size");
2018 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol();
2019 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol();
2020 Asm->EmitLabelDifference(end, begin, 2);
2021 Asm->OutStreamer.EmitLabel(begin);
2023 APByteStreamer Streamer(*Asm);
2024 emitDebugLocEntry(Streamer, Entry);
2026 Asm->OutStreamer.EmitLabel(end);
2029 // Emit locations into the debug loc section.
2030 void DwarfDebug::emitDebugLoc() {
2031 // Start the dwarf loc section.
2032 Asm->OutStreamer.SwitchSection(
2033 Asm->getObjFileLowering().getDwarfLocSection());
2034 unsigned char Size = Asm->getDataLayout().getPointerSize();
2035 for (const auto &DebugLoc : DotDebugLocEntries) {
2036 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2037 for (const auto &Entry : DebugLoc.List) {
2038 // Set up the range. This range is relative to the entry point of the
2039 // compile unit. This is a hard coded 0 for low_pc when we're emitting
2040 // ranges, or the DW_AT_low_pc on the compile unit otherwise.
2041 const DwarfCompileUnit *CU = Entry.getCU();
2042 if (CU->getRanges().size() == 1) {
2043 // Grab the begin symbol from the first range as our base.
2044 const MCSymbol *Base = CU->getRanges()[0].getStart();
2045 Asm->EmitLabelDifference(Entry.getBeginSym(), Base, Size);
2046 Asm->EmitLabelDifference(Entry.getEndSym(), Base, Size);
2048 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size);
2049 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size);
2052 emitDebugLocEntryLocation(Entry);
2054 Asm->OutStreamer.EmitIntValue(0, Size);
2055 Asm->OutStreamer.EmitIntValue(0, Size);
2059 void DwarfDebug::emitDebugLocDWO() {
2060 Asm->OutStreamer.SwitchSection(
2061 Asm->getObjFileLowering().getDwarfLocDWOSection());
2062 for (const auto &DebugLoc : DotDebugLocEntries) {
2063 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2064 for (const auto &Entry : DebugLoc.List) {
2065 // Just always use start_length for now - at least that's one address
2066 // rather than two. We could get fancier and try to, say, reuse an
2067 // address we know we've emitted elsewhere (the start of the function?
2068 // The start of the CU or CU subrange that encloses this range?)
2069 Asm->EmitInt8(dwarf::DW_LLE_start_length_entry);
2070 unsigned idx = AddrPool.getIndex(Entry.getBeginSym());
2071 Asm->EmitULEB128(idx);
2072 Asm->EmitLabelDifference(Entry.getEndSym(), Entry.getBeginSym(), 4);
2074 emitDebugLocEntryLocation(Entry);
2076 Asm->EmitInt8(dwarf::DW_LLE_end_of_list_entry);
2081 const MCSymbol *Start, *End;
2084 // Emit a debug aranges section, containing a CU lookup for any
2085 // address we can tie back to a CU.
2086 void DwarfDebug::emitDebugARanges() {
2087 // Start the dwarf aranges section.
2088 Asm->OutStreamer.SwitchSection(
2089 Asm->getObjFileLowering().getDwarfARangesSection());
2091 typedef DenseMap<DwarfCompileUnit *, std::vector<ArangeSpan>> SpansType;
2095 // Build a list of sections used.
2096 std::vector<const MCSection *> Sections;
2097 for (const auto &it : SectionMap) {
2098 const MCSection *Section = it.first;
2099 Sections.push_back(Section);
2102 // Sort the sections into order.
2103 // This is only done to ensure consistent output order across different runs.
2104 std::sort(Sections.begin(), Sections.end(), SectionSort);
2106 // Build a set of address spans, sorted by CU.
2107 for (const MCSection *Section : Sections) {
2108 SmallVector<SymbolCU, 8> &List = SectionMap[Section];
2109 if (List.size() < 2)
2112 // Sort the symbols by offset within the section.
2113 std::sort(List.begin(), List.end(),
2114 [&](const SymbolCU &A, const SymbolCU &B) {
2115 unsigned IA = A.Sym ? Asm->OutStreamer.GetSymbolOrder(A.Sym) : 0;
2116 unsigned IB = B.Sym ? Asm->OutStreamer.GetSymbolOrder(B.Sym) : 0;
2118 // Symbols with no order assigned should be placed at the end.
2119 // (e.g. section end labels)
2127 // If we have no section (e.g. common), just write out
2128 // individual spans for each symbol.
2130 for (const SymbolCU &Cur : List) {
2132 Span.Start = Cur.Sym;
2135 Spans[Cur.CU].push_back(Span);
2138 // Build spans between each label.
2139 const MCSymbol *StartSym = List[0].Sym;
2140 for (size_t n = 1, e = List.size(); n < e; n++) {
2141 const SymbolCU &Prev = List[n - 1];
2142 const SymbolCU &Cur = List[n];
2144 // Try and build the longest span we can within the same CU.
2145 if (Cur.CU != Prev.CU) {
2147 Span.Start = StartSym;
2149 Spans[Prev.CU].push_back(Span);
2156 unsigned PtrSize = Asm->getDataLayout().getPointerSize();
2158 // Build a list of CUs used.
2159 std::vector<DwarfCompileUnit *> CUs;
2160 for (const auto &it : Spans) {
2161 DwarfCompileUnit *CU = it.first;
2165 // Sort the CU list (again, to ensure consistent output order).
2166 std::sort(CUs.begin(), CUs.end(), [](const DwarfUnit *A, const DwarfUnit *B) {
2167 return A->getUniqueID() < B->getUniqueID();
2170 // Emit an arange table for each CU we used.
2171 for (DwarfCompileUnit *CU : CUs) {
2172 std::vector<ArangeSpan> &List = Spans[CU];
2174 // Emit size of content not including length itself.
2175 unsigned ContentSize =
2176 sizeof(int16_t) + // DWARF ARange version number
2177 sizeof(int32_t) + // Offset of CU in the .debug_info section
2178 sizeof(int8_t) + // Pointer Size (in bytes)
2179 sizeof(int8_t); // Segment Size (in bytes)
2181 unsigned TupleSize = PtrSize * 2;
2183 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple.
2185 OffsetToAlignment(sizeof(int32_t) + ContentSize, TupleSize);
2187 ContentSize += Padding;
2188 ContentSize += (List.size() + 1) * TupleSize;
2190 // For each compile unit, write the list of spans it covers.
2191 Asm->OutStreamer.AddComment("Length of ARange Set");
2192 Asm->EmitInt32(ContentSize);
2193 Asm->OutStreamer.AddComment("DWARF Arange version number");
2194 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION);
2195 Asm->OutStreamer.AddComment("Offset Into Debug Info Section");
2196 Asm->EmitSectionOffset(CU->getLocalLabelBegin(), CU->getLocalSectionSym());
2197 Asm->OutStreamer.AddComment("Address Size (in bytes)");
2198 Asm->EmitInt8(PtrSize);
2199 Asm->OutStreamer.AddComment("Segment Size (in bytes)");
2202 Asm->OutStreamer.EmitFill(Padding, 0xff);
2204 for (const ArangeSpan &Span : List) {
2205 Asm->EmitLabelReference(Span.Start, PtrSize);
2207 // Calculate the size as being from the span start to it's end.
2209 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize);
2211 // For symbols without an end marker (e.g. common), we
2212 // write a single arange entry containing just that one symbol.
2213 uint64_t Size = SymSize[Span.Start];
2217 Asm->OutStreamer.EmitIntValue(Size, PtrSize);
2221 Asm->OutStreamer.AddComment("ARange terminator");
2222 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2223 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2227 // Emit visible names into a debug ranges section.
2228 void DwarfDebug::emitDebugRanges() {
2229 // Start the dwarf ranges section.
2230 Asm->OutStreamer.SwitchSection(
2231 Asm->getObjFileLowering().getDwarfRangesSection());
2233 // Size for our labels.
2234 unsigned char Size = Asm->getDataLayout().getPointerSize();
2236 // Grab the specific ranges for the compile units in the module.
2237 for (const auto &I : CUMap) {
2238 DwarfCompileUnit *TheCU = I.second;
2240 // Iterate over the misc ranges for the compile units in the module.
2241 for (const RangeSpanList &List : TheCU->getRangeLists()) {
2242 // Emit our symbol so we can find the beginning of the range.
2243 Asm->OutStreamer.EmitLabel(List.getSym());
2245 for (const RangeSpan &Range : List.getRanges()) {
2246 const MCSymbol *Begin = Range.getStart();
2247 const MCSymbol *End = Range.getEnd();
2248 assert(Begin && "Range without a begin symbol?");
2249 assert(End && "Range without an end symbol?");
2250 if (TheCU->getRanges().size() == 1) {
2251 // Grab the begin symbol from the first range as our base.
2252 const MCSymbol *Base = TheCU->getRanges()[0].getStart();
2253 Asm->EmitLabelDifference(Begin, Base, Size);
2254 Asm->EmitLabelDifference(End, Base, Size);
2256 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2257 Asm->OutStreamer.EmitSymbolValue(End, Size);
2261 // And terminate the list with two 0 values.
2262 Asm->OutStreamer.EmitIntValue(0, Size);
2263 Asm->OutStreamer.EmitIntValue(0, Size);
2266 // Now emit a range for the CU itself.
2267 if (TheCU->getRanges().size() > 1) {
2268 Asm->OutStreamer.EmitLabel(
2269 Asm->GetTempSymbol("cu_ranges", TheCU->getUniqueID()));
2270 for (const RangeSpan &Range : TheCU->getRanges()) {
2271 const MCSymbol *Begin = Range.getStart();
2272 const MCSymbol *End = Range.getEnd();
2273 assert(Begin && "Range without a begin symbol?");
2274 assert(End && "Range without an end symbol?");
2275 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2276 Asm->OutStreamer.EmitSymbolValue(End, Size);
2278 // And terminate the list with two 0 values.
2279 Asm->OutStreamer.EmitIntValue(0, Size);
2280 Asm->OutStreamer.EmitIntValue(0, Size);
2285 // DWARF5 Experimental Separate Dwarf emitters.
2287 void DwarfDebug::initSkeletonUnit(const DwarfUnit &U, DIE &Die,
2288 std::unique_ptr<DwarfUnit> NewU) {
2289 NewU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name,
2290 U.getCUNode().getSplitDebugFilename());
2292 if (!CompilationDir.empty())
2293 NewU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
2295 addGnuPubAttributes(*NewU, Die);
2297 SkeletonHolder.addUnit(std::move(NewU));
2300 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list,
2301 // DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id,
2302 // DW_AT_addr_base, DW_AT_ranges_base.
2303 DwarfCompileUnit &DwarfDebug::constructSkeletonCU(const DwarfCompileUnit &CU) {
2305 auto OwnedUnit = make_unique<DwarfCompileUnit>(
2306 CU.getUniqueID(), CU.getCUNode(), Asm, this, &SkeletonHolder);
2307 DwarfCompileUnit &NewCU = *OwnedUnit;
2308 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
2309 DwarfInfoSectionSym);
2311 NewCU.initStmtList(DwarfLineSectionSym);
2313 initSkeletonUnit(CU, NewCU.getUnitDie(), std::move(OwnedUnit));
2318 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_dwo_name,
2320 DwarfTypeUnit &DwarfDebug::constructSkeletonTU(DwarfTypeUnit &TU) {
2321 DwarfCompileUnit &CU = static_cast<DwarfCompileUnit &>(
2322 *SkeletonHolder.getUnits()[TU.getCU().getUniqueID()]);
2324 auto OwnedUnit = make_unique<DwarfTypeUnit>(TU.getUniqueID(), CU, Asm, this,
2326 DwarfTypeUnit &NewTU = *OwnedUnit;
2327 NewTU.setTypeSignature(TU.getTypeSignature());
2328 NewTU.setType(nullptr);
2330 Asm->getObjFileLowering().getDwarfTypesSection(TU.getTypeSignature()));
2332 initSkeletonUnit(TU, NewTU.getUnitDie(), std::move(OwnedUnit));
2336 // Emit the .debug_info.dwo section for separated dwarf. This contains the
2337 // compile units that would normally be in debug_info.
2338 void DwarfDebug::emitDebugInfoDWO() {
2339 assert(useSplitDwarf() && "No split dwarf debug info?");
2340 // Don't pass an abbrev symbol, using a constant zero instead so as not to
2341 // emit relocations into the dwo file.
2342 InfoHolder.emitUnits(this, /* AbbrevSymbol */ nullptr);
2345 // Emit the .debug_abbrev.dwo section for separated dwarf. This contains the
2346 // abbreviations for the .debug_info.dwo section.
2347 void DwarfDebug::emitDebugAbbrevDWO() {
2348 assert(useSplitDwarf() && "No split dwarf?");
2349 InfoHolder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection());
2352 void DwarfDebug::emitDebugLineDWO() {
2353 assert(useSplitDwarf() && "No split dwarf?");
2354 Asm->OutStreamer.SwitchSection(
2355 Asm->getObjFileLowering().getDwarfLineDWOSection());
2356 SplitTypeUnitFileTable.Emit(Asm->OutStreamer);
2359 // Emit the .debug_str.dwo section for separated dwarf. This contains the
2360 // string section and is identical in format to traditional .debug_str
2362 void DwarfDebug::emitDebugStrDWO() {
2363 assert(useSplitDwarf() && "No split dwarf?");
2364 const MCSection *OffSec =
2365 Asm->getObjFileLowering().getDwarfStrOffDWOSection();
2366 const MCSymbol *StrSym = DwarfStrSectionSym;
2367 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(),
2371 MCDwarfDwoLineTable *DwarfDebug::getDwoLineTable(const DwarfCompileUnit &CU) {
2372 if (!useSplitDwarf())
2375 SplitTypeUnitFileTable.setCompilationDir(CU.getCUNode().getDirectory());
2376 return &SplitTypeUnitFileTable;
2379 static uint64_t makeTypeSignature(StringRef Identifier) {
2381 Hash.update(Identifier);
2382 // ... take the least significant 8 bytes and return those. Our MD5
2383 // implementation always returns its results in little endian, swap bytes
2385 MD5::MD5Result Result;
2387 return *reinterpret_cast<support::ulittle64_t *>(Result + 8);
2390 void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU,
2391 StringRef Identifier, DIE &RefDie,
2392 DICompositeType CTy) {
2393 // Fast path if we're building some type units and one has already used the
2394 // address pool we know we're going to throw away all this work anyway, so
2395 // don't bother building dependent types.
2396 if (!TypeUnitsUnderConstruction.empty() && AddrPool.hasBeenUsed())
2399 const DwarfTypeUnit *&TU = DwarfTypeUnits[CTy];
2401 CU.addDIETypeSignature(RefDie, *TU);
2405 bool TopLevelType = TypeUnitsUnderConstruction.empty();
2406 AddrPool.resetUsedFlag();
2409 make_unique<DwarfTypeUnit>(InfoHolder.getUnits().size(), CU, Asm, this,
2410 &InfoHolder, getDwoLineTable(CU));
2411 DwarfTypeUnit &NewTU = *OwnedUnit;
2412 DIE &UnitDie = NewTU.getUnitDie();
2414 TypeUnitsUnderConstruction.push_back(
2415 std::make_pair(std::move(OwnedUnit), CTy));
2417 NewTU.addUInt(UnitDie, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
2420 uint64_t Signature = makeTypeSignature(Identifier);
2421 NewTU.setTypeSignature(Signature);
2423 if (!useSplitDwarf())
2424 CU.applyStmtList(UnitDie);
2426 // FIXME: Skip using COMDAT groups for type units in the .dwo file once tools
2427 // such as DWP ( http://gcc.gnu.org/wiki/DebugFissionDWP ) can cope with it.
2430 ? Asm->getObjFileLowering().getDwarfTypesDWOSection(Signature)
2431 : Asm->getObjFileLowering().getDwarfTypesSection(Signature));
2433 NewTU.setType(NewTU.createTypeDIE(CTy));
2436 auto TypeUnitsToAdd = std::move(TypeUnitsUnderConstruction);
2437 TypeUnitsUnderConstruction.clear();
2439 // Types referencing entries in the address table cannot be placed in type
2441 if (AddrPool.hasBeenUsed()) {
2443 // Remove all the types built while building this type.
2444 // This is pessimistic as some of these types might not be dependent on
2445 // the type that used an address.
2446 for (const auto &TU : TypeUnitsToAdd)
2447 DwarfTypeUnits.erase(TU.second);
2449 // Construct this type in the CU directly.
2450 // This is inefficient because all the dependent types will be rebuilt
2451 // from scratch, including building them in type units, discovering that
2452 // they depend on addresses, throwing them out and rebuilding them.
2453 CU.constructTypeDIE(RefDie, CTy);
2457 // If the type wasn't dependent on fission addresses, finish adding the type
2458 // and all its dependent types.
2459 for (auto &TU : TypeUnitsToAdd) {
2460 if (useSplitDwarf())
2461 TU.first->setSkeleton(constructSkeletonTU(*TU.first));
2462 InfoHolder.addUnit(std::move(TU.first));
2465 CU.addDIETypeSignature(RefDie, NewTU);
2468 void DwarfDebug::attachLowHighPC(DwarfCompileUnit &Unit, DIE &D,
2469 MCSymbol *Begin, MCSymbol *End) {
2470 assert(Begin && "Begin label should not be null!");
2471 assert(End && "End label should not be null!");
2472 assert(Begin->isDefined() && "Invalid starting label");
2473 assert(End->isDefined() && "Invalid end label");
2475 Unit.addLabelAddress(D, dwarf::DW_AT_low_pc, Begin);
2476 if (DwarfVersion < 4)
2477 Unit.addLabelAddress(D, dwarf::DW_AT_high_pc, End);
2479 Unit.addLabelDelta(D, dwarf::DW_AT_high_pc, End, Begin);
2482 // Accelerator table mutators - add each name along with its companion
2483 // DIE to the proper table while ensuring that the name that we're going
2484 // to reference is in the string table. We do this since the names we
2485 // add may not only be identical to the names in the DIE.
2486 void DwarfDebug::addAccelName(StringRef Name, const DIE &Die) {
2487 if (!useDwarfAccelTables())
2489 AccelNames.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2493 void DwarfDebug::addAccelObjC(StringRef Name, const DIE &Die) {
2494 if (!useDwarfAccelTables())
2496 AccelObjC.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2500 void DwarfDebug::addAccelNamespace(StringRef Name, const DIE &Die) {
2501 if (!useDwarfAccelTables())
2503 AccelNamespace.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2507 void DwarfDebug::addAccelType(StringRef Name, const DIE &Die, char Flags) {
2508 if (!useDwarfAccelTables())
2510 AccelTypes.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),