1 //===-- llvm/CodeGen/DwarfDebug.cpp - Dwarf Debug Framework ---------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains support for writing dwarf debug info into asm files.
12 //===----------------------------------------------------------------------===//
14 #include "ByteStreamer.h"
15 #include "DwarfDebug.h"
18 #include "DwarfUnit.h"
19 #include "llvm/ADT/STLExtras.h"
20 #include "llvm/ADT/Statistic.h"
21 #include "llvm/ADT/StringExtras.h"
22 #include "llvm/ADT/Triple.h"
23 #include "llvm/CodeGen/MachineFunction.h"
24 #include "llvm/CodeGen/MachineModuleInfo.h"
25 #include "llvm/IR/Constants.h"
26 #include "llvm/IR/DIBuilder.h"
27 #include "llvm/IR/DataLayout.h"
28 #include "llvm/IR/DebugInfo.h"
29 #include "llvm/IR/Instructions.h"
30 #include "llvm/IR/Module.h"
31 #include "llvm/IR/ValueHandle.h"
32 #include "llvm/MC/MCAsmInfo.h"
33 #include "llvm/MC/MCSection.h"
34 #include "llvm/MC/MCStreamer.h"
35 #include "llvm/MC/MCSymbol.h"
36 #include "llvm/Support/CommandLine.h"
37 #include "llvm/Support/Debug.h"
38 #include "llvm/Support/Dwarf.h"
39 #include "llvm/Support/ErrorHandling.h"
40 #include "llvm/Support/FormattedStream.h"
41 #include "llvm/Support/LEB128.h"
42 #include "llvm/Support/MD5.h"
43 #include "llvm/Support/Path.h"
44 #include "llvm/Support/Timer.h"
45 #include "llvm/Target/TargetFrameLowering.h"
46 #include "llvm/Target/TargetLoweringObjectFile.h"
47 #include "llvm/Target/TargetMachine.h"
48 #include "llvm/Target/TargetOptions.h"
49 #include "llvm/Target/TargetRegisterInfo.h"
52 #define DEBUG_TYPE "dwarfdebug"
55 DisableDebugInfoPrinting("disable-debug-info-print", cl::Hidden,
56 cl::desc("Disable debug info printing"));
58 static cl::opt<bool> UnknownLocations(
59 "use-unknown-locations", cl::Hidden,
60 cl::desc("Make an absence of debug location information explicit."),
64 GenerateGnuPubSections("generate-gnu-dwarf-pub-sections", cl::Hidden,
65 cl::desc("Generate GNU-style pubnames and pubtypes"),
68 static cl::opt<bool> GenerateARangeSection("generate-arange-section",
70 cl::desc("Generate dwarf aranges"),
74 enum DefaultOnOff { Default, Enable, Disable };
77 static cl::opt<DefaultOnOff>
78 DwarfAccelTables("dwarf-accel-tables", cl::Hidden,
79 cl::desc("Output prototype dwarf accelerator tables."),
80 cl::values(clEnumVal(Default, "Default for platform"),
81 clEnumVal(Enable, "Enabled"),
82 clEnumVal(Disable, "Disabled"), clEnumValEnd),
85 static cl::opt<DefaultOnOff>
86 SplitDwarf("split-dwarf", cl::Hidden,
87 cl::desc("Output DWARF5 split debug info."),
88 cl::values(clEnumVal(Default, "Default for platform"),
89 clEnumVal(Enable, "Enabled"),
90 clEnumVal(Disable, "Disabled"), clEnumValEnd),
93 static cl::opt<DefaultOnOff>
94 DwarfPubSections("generate-dwarf-pub-sections", cl::Hidden,
95 cl::desc("Generate DWARF pubnames and pubtypes sections"),
96 cl::values(clEnumVal(Default, "Default for platform"),
97 clEnumVal(Enable, "Enabled"),
98 clEnumVal(Disable, "Disabled"), clEnumValEnd),
101 static cl::opt<unsigned>
102 DwarfVersionNumber("dwarf-version", cl::Hidden,
103 cl::desc("Generate DWARF for dwarf version."), cl::init(0));
105 static const char *const DWARFGroupName = "DWARF Emission";
106 static const char *const DbgTimerName = "DWARF Debug Writer";
108 //===----------------------------------------------------------------------===//
110 /// resolve - Look in the DwarfDebug map for the MDNode that
111 /// corresponds to the reference.
112 template <typename T> T DbgVariable::resolve(DIRef<T> Ref) const {
113 return DD->resolve(Ref);
116 bool DbgVariable::isBlockByrefVariable() const {
117 assert(Var.isVariable() && "Invalid complex DbgVariable!");
118 return Var.isBlockByrefVariable(DD->getTypeIdentifierMap());
121 DIType DbgVariable::getType() const {
122 DIType Ty = Var.getType().resolve(DD->getTypeIdentifierMap());
123 // FIXME: isBlockByrefVariable should be reformulated in terms of complex
124 // addresses instead.
125 if (Var.isBlockByrefVariable(DD->getTypeIdentifierMap())) {
126 /* Byref variables, in Blocks, are declared by the programmer as
127 "SomeType VarName;", but the compiler creates a
128 __Block_byref_x_VarName struct, and gives the variable VarName
129 either the struct, or a pointer to the struct, as its type. This
130 is necessary for various behind-the-scenes things the compiler
131 needs to do with by-reference variables in blocks.
133 However, as far as the original *programmer* is concerned, the
134 variable should still have type 'SomeType', as originally declared.
136 The following function dives into the __Block_byref_x_VarName
137 struct to find the original type of the variable. This will be
138 passed back to the code generating the type for the Debug
139 Information Entry for the variable 'VarName'. 'VarName' will then
140 have the original type 'SomeType' in its debug information.
142 The original type 'SomeType' will be the type of the field named
143 'VarName' inside the __Block_byref_x_VarName struct.
145 NOTE: In order for this to not completely fail on the debugger
146 side, the Debug Information Entry for the variable VarName needs to
147 have a DW_AT_location that tells the debugger how to unwind through
148 the pointers and __Block_byref_x_VarName struct to find the actual
149 value of the variable. The function addBlockByrefType does this. */
151 uint16_t tag = Ty.getTag();
153 if (tag == dwarf::DW_TAG_pointer_type)
154 subType = resolve(DIDerivedType(Ty).getTypeDerivedFrom());
156 DIArray Elements = DICompositeType(subType).getTypeArray();
157 for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) {
158 DIDerivedType DT(Elements.getElement(i));
159 if (getName() == DT.getName())
160 return (resolve(DT.getTypeDerivedFrom()));
166 static LLVM_CONSTEXPR DwarfAccelTable::Atom TypeAtoms[] = {
167 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, dwarf::DW_FORM_data4),
168 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_tag, dwarf::DW_FORM_data2),
169 DwarfAccelTable::Atom(dwarf::DW_ATOM_type_flags, dwarf::DW_FORM_data1)};
171 DwarfDebug::DwarfDebug(AsmPrinter *A, Module *M)
172 : Asm(A), MMI(Asm->MMI), FirstCU(nullptr), PrevLabel(nullptr),
173 GlobalRangeCount(0), InfoHolder(A, "info_string", DIEValueAllocator),
174 UsedNonDefaultText(false),
175 SkeletonHolder(A, "skel_string", DIEValueAllocator),
176 AccelNames(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset,
177 dwarf::DW_FORM_data4)),
178 AccelObjC(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset,
179 dwarf::DW_FORM_data4)),
180 AccelNamespace(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset,
181 dwarf::DW_FORM_data4)),
182 AccelTypes(TypeAtoms) {
184 DwarfInfoSectionSym = DwarfAbbrevSectionSym = DwarfStrSectionSym = nullptr;
185 DwarfDebugRangeSectionSym = DwarfDebugLocSectionSym = nullptr;
186 DwarfLineSectionSym = nullptr;
187 DwarfAddrSectionSym = nullptr;
188 DwarfAbbrevDWOSectionSym = DwarfStrDWOSectionSym = nullptr;
189 FunctionBeginSym = FunctionEndSym = nullptr;
193 // Turn on accelerator tables for Darwin by default, pubnames by
194 // default for non-Darwin, and handle split dwarf.
195 bool IsDarwin = Triple(A->getTargetTriple()).isOSDarwin();
197 if (DwarfAccelTables == Default)
198 HasDwarfAccelTables = IsDarwin;
200 HasDwarfAccelTables = DwarfAccelTables == Enable;
202 if (SplitDwarf == Default)
203 HasSplitDwarf = false;
205 HasSplitDwarf = SplitDwarf == Enable;
207 if (DwarfPubSections == Default)
208 HasDwarfPubSections = !IsDarwin;
210 HasDwarfPubSections = DwarfPubSections == Enable;
212 DwarfVersion = DwarfVersionNumber ? DwarfVersionNumber
213 : MMI->getModule()->getDwarfVersion();
216 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
221 // Define out of line so we don't have to include DwarfUnit.h in DwarfDebug.h.
222 DwarfDebug::~DwarfDebug() { }
224 // Switch to the specified MCSection and emit an assembler
225 // temporary label to it if SymbolStem is specified.
226 static MCSymbol *emitSectionSym(AsmPrinter *Asm, const MCSection *Section,
227 const char *SymbolStem = nullptr) {
228 Asm->OutStreamer.SwitchSection(Section);
232 MCSymbol *TmpSym = Asm->GetTempSymbol(SymbolStem);
233 Asm->OutStreamer.EmitLabel(TmpSym);
237 static bool isObjCClass(StringRef Name) {
238 return Name.startswith("+") || Name.startswith("-");
241 static bool hasObjCCategory(StringRef Name) {
242 if (!isObjCClass(Name))
245 return Name.find(") ") != StringRef::npos;
248 static void getObjCClassCategory(StringRef In, StringRef &Class,
249 StringRef &Category) {
250 if (!hasObjCCategory(In)) {
251 Class = In.slice(In.find('[') + 1, In.find(' '));
256 Class = In.slice(In.find('[') + 1, In.find('('));
257 Category = In.slice(In.find('[') + 1, In.find(' '));
261 static StringRef getObjCMethodName(StringRef In) {
262 return In.slice(In.find(' ') + 1, In.find(']'));
265 // Helper for sorting sections into a stable output order.
266 static bool SectionSort(const MCSection *A, const MCSection *B) {
267 std::string LA = (A ? A->getLabelBeginName() : "");
268 std::string LB = (B ? B->getLabelBeginName() : "");
272 // Add the various names to the Dwarf accelerator table names.
273 // TODO: Determine whether or not we should add names for programs
274 // that do not have a DW_AT_name or DW_AT_linkage_name field - this
275 // is only slightly different than the lookup of non-standard ObjC names.
276 void DwarfDebug::addSubprogramNames(DISubprogram SP, DIE &Die) {
277 if (!SP.isDefinition())
279 addAccelName(SP.getName(), Die);
281 // If the linkage name is different than the name, go ahead and output
282 // that as well into the name table.
283 if (SP.getLinkageName() != "" && SP.getName() != SP.getLinkageName())
284 addAccelName(SP.getLinkageName(), Die);
286 // If this is an Objective-C selector name add it to the ObjC accelerator
288 if (isObjCClass(SP.getName())) {
289 StringRef Class, Category;
290 getObjCClassCategory(SP.getName(), Class, Category);
291 addAccelObjC(Class, Die);
293 addAccelObjC(Category, Die);
294 // Also add the base method name to the name table.
295 addAccelName(getObjCMethodName(SP.getName()), Die);
299 /// isSubprogramContext - Return true if Context is either a subprogram
300 /// or another context nested inside a subprogram.
301 bool DwarfDebug::isSubprogramContext(const MDNode *Context) {
304 DIDescriptor D(Context);
305 if (D.isSubprogram())
308 return isSubprogramContext(resolve(DIType(Context).getContext()));
312 // Find DIE for the given subprogram and attach appropriate DW_AT_low_pc
313 // and DW_AT_high_pc attributes. If there are global variables in this
314 // scope then create and insert DIEs for these variables.
315 DIE &DwarfDebug::updateSubprogramScopeDIE(DwarfCompileUnit &SPCU,
317 DIE *SPDie = SPCU.getDIE(SP);
319 assert(SPDie && "Unable to find subprogram DIE!");
321 // If we're updating an abstract DIE, then we will be adding the children and
322 // object pointer later on. But what we don't want to do is process the
323 // concrete DIE twice.
324 if (DIE *AbsSPDIE = AbstractSPDies.lookup(SP)) {
325 // Pick up abstract subprogram DIE.
326 SPDie = &SPCU.createAndAddDIE(dwarf::DW_TAG_subprogram, SPCU.getUnitDie());
327 SPCU.addDIEEntry(*SPDie, dwarf::DW_AT_abstract_origin, *AbsSPDIE);
329 DISubprogram SPDecl = SP.getFunctionDeclaration();
330 if (!SPDecl.isSubprogram()) {
331 // There is not any need to generate specification DIE for a function
332 // defined at compile unit level. If a function is defined inside another
333 // function then gdb prefers the definition at top level and but does not
334 // expect specification DIE in parent function. So avoid creating
335 // specification DIE for a function defined inside a function.
336 DIScope SPContext = resolve(SP.getContext());
337 if (SP.isDefinition() && !SPContext.isCompileUnit() &&
338 !SPContext.isFile() && !isSubprogramContext(SPContext)) {
339 SPCU.addFlag(*SPDie, dwarf::DW_AT_declaration);
342 DICompositeType SPTy = SP.getType();
343 DIArray Args = SPTy.getTypeArray();
344 uint16_t SPTag = SPTy.getTag();
345 if (SPTag == dwarf::DW_TAG_subroutine_type)
346 SPCU.constructSubprogramArguments(*SPDie, Args);
347 DIE *SPDeclDie = SPDie;
349 &SPCU.createAndAddDIE(dwarf::DW_TAG_subprogram, SPCU.getUnitDie());
350 SPCU.addDIEEntry(*SPDie, dwarf::DW_AT_specification, *SPDeclDie);
355 attachLowHighPC(SPCU, *SPDie, FunctionBeginSym, FunctionEndSym);
357 const TargetRegisterInfo *RI = Asm->TM.getRegisterInfo();
358 MachineLocation Location(RI->getFrameRegister(*Asm->MF));
359 SPCU.addAddress(*SPDie, dwarf::DW_AT_frame_base, Location);
361 // Add name to the name table, we do this here because we're guaranteed
362 // to have concrete versions of our DW_TAG_subprogram nodes.
363 addSubprogramNames(SP, *SPDie);
368 /// Check whether we should create a DIE for the given Scope, return true
369 /// if we don't create a DIE (the corresponding DIE is null).
370 bool DwarfDebug::isLexicalScopeDIENull(LexicalScope *Scope) {
371 if (Scope->isAbstractScope())
374 // We don't create a DIE if there is no Range.
375 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges();
379 if (Ranges.size() > 1)
382 // We don't create a DIE if we have a single Range and the end label
384 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin();
385 MCSymbol *End = getLabelAfterInsn(RI->second);
389 static void addSectionLabel(AsmPrinter &Asm, DwarfUnit &U, DIE &D,
390 dwarf::Attribute A, const MCSymbol *L,
391 const MCSymbol *Sec) {
392 if (Asm.MAI->doesDwarfUseRelocationsAcrossSections())
393 U.addSectionLabel(D, A, L);
395 U.addSectionDelta(D, A, L, Sec);
398 void DwarfDebug::addScopeRangeList(DwarfCompileUnit &TheCU, DIE &ScopeDIE,
399 const SmallVectorImpl<InsnRange> &Range) {
400 // Emit offset in .debug_range as a relocatable label. emitDIE will handle
401 // emitting it appropriately.
402 MCSymbol *RangeSym = Asm->GetTempSymbol("debug_ranges", GlobalRangeCount++);
404 // Under fission, ranges are specified by constant offsets relative to the
405 // CU's DW_AT_GNU_ranges_base.
407 TheCU.addSectionDelta(ScopeDIE, dwarf::DW_AT_ranges, RangeSym,
408 DwarfDebugRangeSectionSym);
410 addSectionLabel(*Asm, TheCU, ScopeDIE, dwarf::DW_AT_ranges, RangeSym,
411 DwarfDebugRangeSectionSym);
413 RangeSpanList List(RangeSym);
414 for (const InsnRange &R : Range) {
415 RangeSpan Span(getLabelBeforeInsn(R.first), getLabelAfterInsn(R.second));
416 List.addRange(std::move(Span));
419 // Add the range list to the set of ranges to be emitted.
420 TheCU.addRangeList(std::move(List));
423 // Construct new DW_TAG_lexical_block for this scope and attach
424 // DW_AT_low_pc/DW_AT_high_pc labels.
426 DwarfDebug::constructLexicalScopeDIE(DwarfCompileUnit &TheCU,
427 LexicalScope *Scope) {
428 if (isLexicalScopeDIENull(Scope))
431 auto ScopeDIE = make_unique<DIE>(dwarf::DW_TAG_lexical_block);
432 if (Scope->isAbstractScope())
435 const SmallVectorImpl<InsnRange> &ScopeRanges = Scope->getRanges();
437 // If we have multiple ranges, emit them into the range section.
438 if (ScopeRanges.size() > 1) {
439 addScopeRangeList(TheCU, *ScopeDIE, ScopeRanges);
443 // Construct the address range for this DIE.
444 SmallVectorImpl<InsnRange>::const_iterator RI = ScopeRanges.begin();
445 MCSymbol *Start = getLabelBeforeInsn(RI->first);
446 MCSymbol *End = getLabelAfterInsn(RI->second);
447 assert(End && "End label should not be null!");
449 assert(Start->isDefined() && "Invalid starting label for an inlined scope!");
450 assert(End->isDefined() && "Invalid end label for an inlined scope!");
452 attachLowHighPC(TheCU, *ScopeDIE, Start, End);
457 // This scope represents inlined body of a function. Construct DIE to
458 // represent this concrete inlined copy of the function.
460 DwarfDebug::constructInlinedScopeDIE(DwarfCompileUnit &TheCU,
461 LexicalScope *Scope) {
462 const SmallVectorImpl<InsnRange> &ScopeRanges = Scope->getRanges();
463 assert(!ScopeRanges.empty() &&
464 "LexicalScope does not have instruction markers!");
466 if (!Scope->getScopeNode())
468 DIScope DS(Scope->getScopeNode());
469 DISubprogram InlinedSP = getDISubprogram(DS);
470 DIE *OriginDIE = TheCU.getDIE(InlinedSP);
472 DEBUG(dbgs() << "Unable to find original DIE for an inlined subprogram.");
476 auto ScopeDIE = make_unique<DIE>(dwarf::DW_TAG_inlined_subroutine);
477 TheCU.addDIEEntry(*ScopeDIE, dwarf::DW_AT_abstract_origin, *OriginDIE);
479 // If we have multiple ranges, emit them into the range section.
480 if (ScopeRanges.size() > 1)
481 addScopeRangeList(TheCU, *ScopeDIE, ScopeRanges);
483 SmallVectorImpl<InsnRange>::const_iterator RI = ScopeRanges.begin();
484 MCSymbol *StartLabel = getLabelBeforeInsn(RI->first);
485 MCSymbol *EndLabel = getLabelAfterInsn(RI->second);
487 if (!StartLabel || !EndLabel)
488 llvm_unreachable("Unexpected Start and End labels for an inlined scope!");
490 assert(StartLabel->isDefined() &&
491 "Invalid starting label for an inlined scope!");
492 assert(EndLabel->isDefined() && "Invalid end label for an inlined scope!");
494 attachLowHighPC(TheCU, *ScopeDIE, StartLabel, EndLabel);
497 InlinedSubprogramDIEs.insert(OriginDIE);
499 // Add the call site information to the DIE.
500 DILocation DL(Scope->getInlinedAt());
501 TheCU.addUInt(*ScopeDIE, dwarf::DW_AT_call_file, None,
502 TheCU.getOrCreateSourceID(DL.getFilename(), DL.getDirectory()));
503 TheCU.addUInt(*ScopeDIE, dwarf::DW_AT_call_line, None, DL.getLineNumber());
505 // Add name to the name table, we do this here because we're guaranteed
506 // to have concrete versions of our DW_TAG_inlined_subprogram nodes.
507 addSubprogramNames(InlinedSP, *ScopeDIE);
512 DIE *DwarfDebug::createScopeChildrenDIE(
513 DwarfCompileUnit &TheCU, LexicalScope *Scope,
514 SmallVectorImpl<std::unique_ptr<DIE>> &Children) {
515 DIE *ObjectPointer = nullptr;
517 // Collect arguments for current function.
518 if (LScopes.isCurrentFunctionScope(Scope)) {
519 for (DbgVariable *ArgDV : CurrentFnArguments)
522 TheCU.constructVariableDIE(*ArgDV, Scope->isAbstractScope()));
523 if (ArgDV->isObjectPointer())
524 ObjectPointer = Children.back().get();
527 // If this is a variadic function, add an unspecified parameter.
528 DISubprogram SP(Scope->getScopeNode());
529 DIArray FnArgs = SP.getType().getTypeArray();
530 if (FnArgs.getElement(FnArgs.getNumElements() - 1)
531 .isUnspecifiedParameter()) {
533 make_unique<DIE>(dwarf::DW_TAG_unspecified_parameters));
537 // Collect lexical scope children first.
538 for (DbgVariable *DV : ScopeVariables.lookup(Scope)) {
540 TheCU.constructVariableDIE(*DV, Scope->isAbstractScope()));
541 if (DV->isObjectPointer())
542 ObjectPointer = Children.back().get();
544 for (LexicalScope *LS : Scope->getChildren())
545 if (std::unique_ptr<DIE> Nested = constructScopeDIE(TheCU, LS))
546 Children.push_back(std::move(Nested));
547 return ObjectPointer;
550 void DwarfDebug::createAndAddScopeChildren(DwarfCompileUnit &TheCU,
552 DISubprogram Sub, DIE &ScopeDIE) {
553 // We create children when the scope DIE is not null.
554 SmallVector<std::unique_ptr<DIE>, 8> Children;
555 if (DIE *ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children))
556 // The declaration will have the object_pointer, otherwise put it on the
557 // definition. This happens with ObjC blocks that have object_pointer on
558 // non-member functions.
559 if (!Sub.getFunctionDeclaration())
560 TheCU.addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, *ObjectPointer);
563 for (auto &I : Children)
564 ScopeDIE.addChild(std::move(I));
567 void DwarfDebug::constructAbstractSubprogramScopeDIE(DwarfCompileUnit &TheCU,
568 LexicalScope *Scope) {
569 assert(Scope && Scope->getScopeNode());
570 assert(Scope->isAbstractScope());
571 assert(!Scope->getInlinedAt());
573 DISubprogram Sub(Scope->getScopeNode());
575 ProcessedSPNodes.insert(Sub);
577 if (DIE *ScopeDIE = TheCU.getDIE(Sub)) {
578 AbstractSPDies.insert(std::make_pair(Sub, ScopeDIE));
579 createAndAddScopeChildren(TheCU, Scope, Sub, *ScopeDIE);
583 DIE &DwarfDebug::constructSubprogramScopeDIE(DwarfCompileUnit &TheCU,
584 LexicalScope *Scope) {
585 assert(Scope && Scope->getScopeNode());
586 assert(!Scope->getInlinedAt());
587 assert(!Scope->isAbstractScope());
588 assert(DIScope(Scope->getScopeNode()).isSubprogram());
590 DISubprogram Sub(Scope->getScopeNode());
592 ProcessedSPNodes.insert(Sub);
594 DIE &ScopeDIE = updateSubprogramScopeDIE(TheCU, Sub);
596 createAndAddScopeChildren(TheCU, Scope, Sub, ScopeDIE);
601 // Construct a DIE for this scope.
602 std::unique_ptr<DIE> DwarfDebug::constructScopeDIE(DwarfCompileUnit &TheCU,
603 LexicalScope *Scope) {
604 if (!Scope || !Scope->getScopeNode())
607 DIScope DS(Scope->getScopeNode());
609 assert((Scope->getInlinedAt() || !DS.isSubprogram()) &&
610 "Only handle inlined subprograms here, use "
611 "constructSubprogramScopeDIE for non-inlined "
614 SmallVector<std::unique_ptr<DIE>, 8> Children;
616 // We try to create the scope DIE first, then the children DIEs. This will
617 // avoid creating un-used children then removing them later when we find out
618 // the scope DIE is null.
619 std::unique_ptr<DIE> ScopeDIE;
620 if (Scope->getInlinedAt()) {
621 ScopeDIE = constructInlinedScopeDIE(TheCU, Scope);
624 // We create children when the scope DIE is not null.
625 createScopeChildrenDIE(TheCU, Scope, Children);
627 // Early exit when we know the scope DIE is going to be null.
628 if (isLexicalScopeDIENull(Scope))
631 // We create children here when we know the scope DIE is not going to be
632 // null and the children will be added to the scope DIE.
633 createScopeChildrenDIE(TheCU, Scope, Children);
635 // There is no need to emit empty lexical block DIE.
636 std::pair<ImportedEntityMap::const_iterator,
637 ImportedEntityMap::const_iterator> Range =
638 std::equal_range(ScopesWithImportedEntities.begin(),
639 ScopesWithImportedEntities.end(),
640 std::pair<const MDNode *, const MDNode *>(DS, nullptr),
642 if (Children.empty() && Range.first == Range.second)
644 ScopeDIE = constructLexicalScopeDIE(TheCU, Scope);
645 assert(ScopeDIE && "Scope DIE should not be null.");
646 for (ImportedEntityMap::const_iterator i = Range.first; i != Range.second;
648 constructImportedEntityDIE(TheCU, i->second, *ScopeDIE);
652 for (auto &I : Children)
653 ScopeDIE->addChild(std::move(I));
658 void DwarfDebug::addGnuPubAttributes(DwarfUnit &U, DIE &D) const {
659 if (!GenerateGnuPubSections)
662 U.addFlag(D, dwarf::DW_AT_GNU_pubnames);
665 // Create new DwarfCompileUnit for the given metadata node with tag
666 // DW_TAG_compile_unit.
667 DwarfCompileUnit &DwarfDebug::constructDwarfCompileUnit(DICompileUnit DIUnit) {
668 StringRef FN = DIUnit.getFilename();
669 CompilationDir = DIUnit.getDirectory();
671 auto OwnedUnit = make_unique<DwarfCompileUnit>(
672 InfoHolder.getUnits().size(), DIUnit, Asm, this, &InfoHolder);
673 DwarfCompileUnit &NewCU = *OwnedUnit;
674 DIE &Die = NewCU.getUnitDie();
675 InfoHolder.addUnit(std::move(OwnedUnit));
677 // LTO with assembly output shares a single line table amongst multiple CUs.
678 // To avoid the compilation directory being ambiguous, let the line table
679 // explicitly describe the directory of all files, never relying on the
680 // compilation directory.
681 if (!Asm->OutStreamer.hasRawTextSupport() || SingleCU)
682 Asm->OutStreamer.getContext().setMCLineTableCompilationDir(
683 NewCU.getUniqueID(), CompilationDir);
685 NewCU.addString(Die, dwarf::DW_AT_producer, DIUnit.getProducer());
686 NewCU.addUInt(Die, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
687 DIUnit.getLanguage());
688 NewCU.addString(Die, dwarf::DW_AT_name, FN);
690 if (!useSplitDwarf()) {
691 NewCU.initStmtList(DwarfLineSectionSym);
693 // If we're using split dwarf the compilation dir is going to be in the
694 // skeleton CU and so we don't need to duplicate it here.
695 if (!CompilationDir.empty())
696 NewCU.addString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
698 addGnuPubAttributes(NewCU, Die);
701 if (DIUnit.isOptimized())
702 NewCU.addFlag(Die, dwarf::DW_AT_APPLE_optimized);
704 StringRef Flags = DIUnit.getFlags();
706 NewCU.addString(Die, dwarf::DW_AT_APPLE_flags, Flags);
708 if (unsigned RVer = DIUnit.getRunTimeVersion())
709 NewCU.addUInt(Die, dwarf::DW_AT_APPLE_major_runtime_vers,
710 dwarf::DW_FORM_data1, RVer);
715 if (useSplitDwarf()) {
716 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoDWOSection(),
717 DwarfInfoDWOSectionSym);
718 NewCU.setSkeleton(constructSkeletonCU(NewCU));
720 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
721 DwarfInfoSectionSym);
723 CUMap.insert(std::make_pair(DIUnit, &NewCU));
724 CUDieMap.insert(std::make_pair(&Die, &NewCU));
728 // Construct subprogram DIE.
729 void DwarfDebug::constructSubprogramDIE(DwarfCompileUnit &TheCU,
731 // FIXME: We should only call this routine once, however, during LTO if a
732 // program is defined in multiple CUs we could end up calling it out of
733 // beginModule as we walk the CUs.
735 DwarfCompileUnit *&CURef = SPMap[N];
741 if (!SP.isDefinition())
742 // This is a method declaration which will be handled while constructing
746 DIE &SubprogramDie = *TheCU.getOrCreateSubprogramDIE(SP);
748 // Expose as a global name.
749 TheCU.addGlobalName(SP.getName(), SubprogramDie, resolve(SP.getContext()));
752 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
754 DIImportedEntity Module(N);
755 assert(Module.Verify());
756 if (DIE *D = TheCU.getOrCreateContextDIE(Module.getContext()))
757 constructImportedEntityDIE(TheCU, Module, *D);
760 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
761 const MDNode *N, DIE &Context) {
762 DIImportedEntity Module(N);
763 assert(Module.Verify());
764 return constructImportedEntityDIE(TheCU, Module, Context);
767 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
768 const DIImportedEntity &Module,
770 assert(Module.Verify() &&
771 "Use one of the MDNode * overloads to handle invalid metadata");
772 DIE &IMDie = TheCU.createAndAddDIE(Module.getTag(), Context, Module);
774 DIDescriptor Entity = resolve(Module.getEntity());
775 if (Entity.isNameSpace())
776 EntityDie = TheCU.getOrCreateNameSpace(DINameSpace(Entity));
777 else if (Entity.isSubprogram())
778 EntityDie = TheCU.getOrCreateSubprogramDIE(DISubprogram(Entity));
779 else if (Entity.isType())
780 EntityDie = TheCU.getOrCreateTypeDIE(DIType(Entity));
782 EntityDie = TheCU.getDIE(Entity);
783 TheCU.addSourceLine(IMDie, Module.getLineNumber(),
784 Module.getContext().getFilename(),
785 Module.getContext().getDirectory());
786 TheCU.addDIEEntry(IMDie, dwarf::DW_AT_import, *EntityDie);
787 StringRef Name = Module.getName();
789 TheCU.addString(IMDie, dwarf::DW_AT_name, Name);
792 // Emit all Dwarf sections that should come prior to the content. Create
793 // global DIEs and emit initial debug info sections. This is invoked by
794 // the target AsmPrinter.
795 void DwarfDebug::beginModule() {
796 if (DisableDebugInfoPrinting)
799 const Module *M = MMI->getModule();
801 // If module has named metadata anchors then use them, otherwise scan the
802 // module using debug info finder to collect debug info.
803 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
806 TypeIdentifierMap = generateDITypeIdentifierMap(CU_Nodes);
808 // Emit initial sections so we can reference labels later.
811 SingleCU = CU_Nodes->getNumOperands() == 1;
813 for (MDNode *N : CU_Nodes->operands()) {
814 DICompileUnit CUNode(N);
815 DwarfCompileUnit &CU = constructDwarfCompileUnit(CUNode);
816 DIArray ImportedEntities = CUNode.getImportedEntities();
817 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
818 ScopesWithImportedEntities.push_back(std::make_pair(
819 DIImportedEntity(ImportedEntities.getElement(i)).getContext(),
820 ImportedEntities.getElement(i)));
821 std::sort(ScopesWithImportedEntities.begin(),
822 ScopesWithImportedEntities.end(), less_first());
823 DIArray GVs = CUNode.getGlobalVariables();
824 for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i)
825 CU.createGlobalVariableDIE(DIGlobalVariable(GVs.getElement(i)));
826 DIArray SPs = CUNode.getSubprograms();
827 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i)
828 constructSubprogramDIE(CU, SPs.getElement(i));
829 DIArray EnumTypes = CUNode.getEnumTypes();
830 for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i)
831 CU.getOrCreateTypeDIE(EnumTypes.getElement(i));
832 DIArray RetainedTypes = CUNode.getRetainedTypes();
833 for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i) {
834 DIType Ty(RetainedTypes.getElement(i));
835 // The retained types array by design contains pointers to
836 // MDNodes rather than DIRefs. Unique them here.
837 DIType UniqueTy(resolve(Ty.getRef()));
838 CU.getOrCreateTypeDIE(UniqueTy);
840 // Emit imported_modules last so that the relevant context is already
842 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
843 constructImportedEntityDIE(CU, ImportedEntities.getElement(i));
846 // Tell MMI that we have debug info.
847 MMI->setDebugInfoAvailability(true);
849 // Prime section data.
850 SectionMap[Asm->getObjFileLowering().getTextSection()];
853 // Attach DW_AT_inline attribute with inlined subprogram DIEs.
854 void DwarfDebug::computeInlinedDIEs() {
855 // Attach DW_AT_inline attribute with inlined subprogram DIEs.
856 for (DIE *ISP : InlinedSubprogramDIEs)
857 FirstCU->addUInt(*ISP, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined);
859 for (const auto &AI : AbstractSPDies) {
860 DIE &ISP = *AI.second;
861 if (InlinedSubprogramDIEs.count(&ISP))
863 FirstCU->addUInt(ISP, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined);
867 // Collect info for variables that were optimized out.
868 void DwarfDebug::collectDeadVariables() {
869 const Module *M = MMI->getModule();
871 if (NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu")) {
872 for (MDNode *N : CU_Nodes->operands()) {
873 DICompileUnit TheCU(N);
874 DIArray Subprograms = TheCU.getSubprograms();
875 for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) {
876 DISubprogram SP(Subprograms.getElement(i));
877 if (ProcessedSPNodes.count(SP) != 0)
879 if (!SP.isSubprogram())
881 if (!SP.isDefinition())
883 DIArray Variables = SP.getVariables();
884 if (Variables.getNumElements() == 0)
887 // Construct subprogram DIE and add variables DIEs.
888 DwarfCompileUnit *SPCU =
889 static_cast<DwarfCompileUnit *>(CUMap.lookup(TheCU));
890 assert(SPCU && "Unable to find Compile Unit!");
891 // FIXME: See the comment in constructSubprogramDIE about duplicate
893 constructSubprogramDIE(*SPCU, SP);
894 DIE *SPDIE = SPCU->getDIE(SP);
895 for (unsigned vi = 0, ve = Variables.getNumElements(); vi != ve; ++vi) {
896 DIVariable DV(Variables.getElement(vi));
897 if (!DV.isVariable())
899 DbgVariable NewVar(DV, nullptr, this);
900 SPDIE->addChild(SPCU->constructVariableDIE(NewVar, false));
907 void DwarfDebug::finalizeModuleInfo() {
908 // Collect info for variables that were optimized out.
909 collectDeadVariables();
911 // Attach DW_AT_inline attribute with inlined subprogram DIEs.
912 computeInlinedDIEs();
914 // Handle anything that needs to be done on a per-unit basis after
915 // all other generation.
916 for (const auto &TheU : getUnits()) {
917 // Emit DW_AT_containing_type attribute to connect types with their
918 // vtable holding type.
919 TheU->constructContainingTypeDIEs();
921 // Add CU specific attributes if we need to add any.
922 if (TheU->getUnitDie().getTag() == dwarf::DW_TAG_compile_unit) {
923 // If we're splitting the dwarf out now that we've got the entire
924 // CU then add the dwo id to it.
925 DwarfCompileUnit *SkCU =
926 static_cast<DwarfCompileUnit *>(TheU->getSkeleton());
927 if (useSplitDwarf()) {
928 // Emit a unique identifier for this CU.
929 uint64_t ID = DIEHash(Asm).computeCUSignature(TheU->getUnitDie());
930 TheU->addUInt(TheU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
931 dwarf::DW_FORM_data8, ID);
932 SkCU->addUInt(SkCU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
933 dwarf::DW_FORM_data8, ID);
935 // We don't keep track of which addresses are used in which CU so this
936 // is a bit pessimistic under LTO.
937 if (!AddrPool.isEmpty())
938 addSectionLabel(*Asm, *SkCU, SkCU->getUnitDie(),
939 dwarf::DW_AT_GNU_addr_base, DwarfAddrSectionSym,
940 DwarfAddrSectionSym);
941 if (!TheU->getRangeLists().empty())
942 addSectionLabel(*Asm, *SkCU, SkCU->getUnitDie(),
943 dwarf::DW_AT_GNU_ranges_base,
944 DwarfDebugRangeSectionSym, DwarfDebugRangeSectionSym);
947 // If we have code split among multiple sections or non-contiguous
948 // ranges of code then emit a DW_AT_ranges attribute on the unit that will
949 // remain in the .o file, otherwise add a DW_AT_low_pc.
950 // FIXME: We should use ranges allow reordering of code ala
951 // .subsections_via_symbols in mach-o. This would mean turning on
952 // ranges for all subprogram DIEs for mach-o.
953 DwarfCompileUnit &U =
954 SkCU ? *SkCU : static_cast<DwarfCompileUnit &>(*TheU);
955 unsigned NumRanges = TheU->getRanges().size();
958 addSectionLabel(*Asm, U, U.getUnitDie(), dwarf::DW_AT_ranges,
959 Asm->GetTempSymbol("cu_ranges", U.getUniqueID()),
960 DwarfDebugRangeSectionSym);
962 // A DW_AT_low_pc attribute may also be specified in combination with
963 // DW_AT_ranges to specify the default base address for use in
964 // location lists (see Section 2.6.2) and range lists (see Section
966 U.addUInt(U.getUnitDie(), dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr,
969 RangeSpan &Range = TheU->getRanges().back();
970 U.addLocalLabelAddress(U.getUnitDie(), dwarf::DW_AT_low_pc,
972 U.addLabelDelta(U.getUnitDie(), dwarf::DW_AT_high_pc, Range.getEnd(),
979 // Compute DIE offsets and sizes.
980 InfoHolder.computeSizeAndOffsets();
982 SkeletonHolder.computeSizeAndOffsets();
985 void DwarfDebug::endSections() {
986 // Filter labels by section.
987 for (const SymbolCU &SCU : ArangeLabels) {
988 if (SCU.Sym->isInSection()) {
989 // Make a note of this symbol and it's section.
990 const MCSection *Section = &SCU.Sym->getSection();
991 if (!Section->getKind().isMetadata())
992 SectionMap[Section].push_back(SCU);
994 // Some symbols (e.g. common/bss on mach-o) can have no section but still
995 // appear in the output. This sucks as we rely on sections to build
996 // arange spans. We can do it without, but it's icky.
997 SectionMap[nullptr].push_back(SCU);
1001 // Build a list of sections used.
1002 std::vector<const MCSection *> Sections;
1003 for (const auto &it : SectionMap) {
1004 const MCSection *Section = it.first;
1005 Sections.push_back(Section);
1008 // Sort the sections into order.
1009 // This is only done to ensure consistent output order across different runs.
1010 std::sort(Sections.begin(), Sections.end(), SectionSort);
1012 // Add terminating symbols for each section.
1013 for (unsigned ID = 0, E = Sections.size(); ID != E; ID++) {
1014 const MCSection *Section = Sections[ID];
1015 MCSymbol *Sym = nullptr;
1018 // We can't call MCSection::getLabelEndName, as it's only safe to do so
1019 // if we know the section name up-front. For user-created sections, the
1020 // resulting label may not be valid to use as a label. (section names can
1021 // use a greater set of characters on some systems)
1022 Sym = Asm->GetTempSymbol("debug_end", ID);
1023 Asm->OutStreamer.SwitchSection(Section);
1024 Asm->OutStreamer.EmitLabel(Sym);
1027 // Insert a final terminator.
1028 SectionMap[Section].push_back(SymbolCU(nullptr, Sym));
1032 // Emit all Dwarf sections that should come after the content.
1033 void DwarfDebug::endModule() {
1034 assert(CurFn == nullptr);
1035 assert(CurMI == nullptr);
1040 // End any existing sections.
1041 // TODO: Does this need to happen?
1044 // Finalize the debug info for the module.
1045 finalizeModuleInfo();
1049 // Emit all the DIEs into a debug info section.
1052 // Corresponding abbreviations into a abbrev section.
1053 emitAbbreviations();
1055 // Emit info into a debug aranges section.
1056 if (GenerateARangeSection)
1059 // Emit info into a debug ranges section.
1062 if (useSplitDwarf()) {
1065 emitDebugAbbrevDWO();
1067 // Emit DWO addresses.
1068 AddrPool.emit(*Asm, Asm->getObjFileLowering().getDwarfAddrSection());
1071 // Emit info into a debug loc section.
1074 // Emit info into the dwarf accelerator table sections.
1075 if (useDwarfAccelTables()) {
1078 emitAccelNamespaces();
1082 // Emit the pubnames and pubtypes sections if requested.
1083 if (HasDwarfPubSections) {
1084 emitDebugPubNames(GenerateGnuPubSections);
1085 emitDebugPubTypes(GenerateGnuPubSections);
1091 // Reset these for the next Module if we have one.
1095 // Find abstract variable, if any, associated with Var.
1096 DbgVariable *DwarfDebug::findAbstractVariable(DIVariable &DV,
1097 DebugLoc ScopeLoc) {
1098 LLVMContext &Ctx = DV->getContext();
1099 // More then one inlined variable corresponds to one abstract variable.
1100 DIVariable Var = cleanseInlinedVariable(DV, Ctx);
1101 DbgVariable *AbsDbgVariable = AbstractVariables.lookup(Var);
1103 return AbsDbgVariable;
1105 LexicalScope *Scope = LScopes.findAbstractScope(ScopeLoc.getScope(Ctx));
1109 AbsDbgVariable = new DbgVariable(Var, nullptr, this);
1110 addScopeVariable(Scope, AbsDbgVariable);
1111 AbstractVariables[Var] = AbsDbgVariable;
1112 return AbsDbgVariable;
1115 // If Var is a current function argument then add it to CurrentFnArguments list.
1116 bool DwarfDebug::addCurrentFnArgument(DbgVariable *Var, LexicalScope *Scope) {
1117 if (!LScopes.isCurrentFunctionScope(Scope))
1119 DIVariable DV = Var->getVariable();
1120 if (DV.getTag() != dwarf::DW_TAG_arg_variable)
1122 unsigned ArgNo = DV.getArgNumber();
1126 size_t Size = CurrentFnArguments.size();
1128 CurrentFnArguments.resize(CurFn->getFunction()->arg_size());
1129 // llvm::Function argument size is not good indicator of how many
1130 // arguments does the function have at source level.
1132 CurrentFnArguments.resize(ArgNo * 2);
1133 CurrentFnArguments[ArgNo - 1] = Var;
1137 // Collect variable information from side table maintained by MMI.
1138 void DwarfDebug::collectVariableInfoFromMMITable(
1139 SmallPtrSet<const MDNode *, 16> &Processed) {
1140 for (const auto &VI : MMI->getVariableDbgInfo()) {
1143 Processed.insert(VI.Var);
1144 DIVariable DV(VI.Var);
1145 LexicalScope *Scope = LScopes.findLexicalScope(VI.Loc);
1147 // If variable scope is not found then skip this variable.
1151 DbgVariable *AbsDbgVariable = findAbstractVariable(DV, VI.Loc);
1152 DbgVariable *RegVar = new DbgVariable(DV, AbsDbgVariable, this);
1153 RegVar->setFrameIndex(VI.Slot);
1154 if (!addCurrentFnArgument(RegVar, Scope))
1155 addScopeVariable(Scope, RegVar);
1157 AbsDbgVariable->setFrameIndex(VI.Slot);
1161 // Get .debug_loc entry for the instruction range starting at MI.
1162 static DebugLocEntry::Value getDebugLocValue(const MachineInstr *MI) {
1163 const MDNode *Var = MI->getDebugVariable();
1165 assert(MI->getNumOperands() == 3);
1166 if (MI->getOperand(0).isReg()) {
1167 MachineLocation MLoc;
1168 // If the second operand is an immediate, this is a
1169 // register-indirect address.
1170 if (!MI->getOperand(1).isImm())
1171 MLoc.set(MI->getOperand(0).getReg());
1173 MLoc.set(MI->getOperand(0).getReg(), MI->getOperand(1).getImm());
1174 return DebugLocEntry::Value(Var, MLoc);
1176 if (MI->getOperand(0).isImm())
1177 return DebugLocEntry::Value(Var, MI->getOperand(0).getImm());
1178 if (MI->getOperand(0).isFPImm())
1179 return DebugLocEntry::Value(Var, MI->getOperand(0).getFPImm());
1180 if (MI->getOperand(0).isCImm())
1181 return DebugLocEntry::Value(Var, MI->getOperand(0).getCImm());
1183 llvm_unreachable("Unexpected 3 operand DBG_VALUE instruction!");
1186 // Find variables for each lexical scope.
1188 DwarfDebug::collectVariableInfo(SmallPtrSet<const MDNode *, 16> &Processed) {
1189 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1190 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1192 // Grab the variable info that was squirreled away in the MMI side-table.
1193 collectVariableInfoFromMMITable(Processed);
1195 for (const MDNode *Var : UserVariables) {
1196 if (Processed.count(Var))
1199 // History contains relevant DBG_VALUE instructions for Var and instructions
1201 SmallVectorImpl<const MachineInstr *> &History = DbgValues[Var];
1202 if (History.empty())
1204 const MachineInstr *MInsn = History.front();
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 Scope = LScopes.findInlinedScope(DebugLoc::getFromDILocation(IA));
1214 Scope = LScopes.findLexicalScope(cast<MDNode>(DV->getOperand(1)));
1215 // If variable scope is not found then skip this variable.
1219 Processed.insert(DV);
1220 assert(MInsn->isDebugValue() && "History must begin with debug value");
1221 DbgVariable *AbsVar = findAbstractVariable(DV, MInsn->getDebugLoc());
1222 DbgVariable *RegVar = new DbgVariable(DV, AbsVar, this);
1223 if (!addCurrentFnArgument(RegVar, Scope))
1224 addScopeVariable(Scope, RegVar);
1226 AbsVar->setMInsn(MInsn);
1228 // Simplify ranges that are fully coalesced.
1229 if (History.size() <= 1 ||
1230 (History.size() == 2 && MInsn->isIdenticalTo(History.back()))) {
1231 RegVar->setMInsn(MInsn);
1235 // Handle multiple DBG_VALUE instructions describing one variable.
1236 RegVar->setDotDebugLocOffset(DotDebugLocEntries.size());
1238 DotDebugLocEntries.resize(DotDebugLocEntries.size() + 1);
1239 DebugLocList &LocList = DotDebugLocEntries.back();
1241 Asm->GetTempSymbol("debug_loc", DotDebugLocEntries.size() - 1);
1242 SmallVector<DebugLocEntry, 4> &DebugLoc = LocList.List;
1243 for (SmallVectorImpl<const MachineInstr *>::const_iterator
1244 HI = History.begin(),
1247 const MachineInstr *Begin = *HI;
1248 assert(Begin->isDebugValue() && "Invalid History entry");
1250 // Check if DBG_VALUE is truncating a range.
1251 if (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() &&
1252 !Begin->getOperand(0).getReg())
1255 // Compute the range for a register location.
1256 const MCSymbol *FLabel = getLabelBeforeInsn(Begin);
1257 const MCSymbol *SLabel = nullptr;
1260 // If Begin is the last instruction in History then its value is valid
1261 // until the end of the function.
1262 SLabel = FunctionEndSym;
1264 const MachineInstr *End = HI[1];
1265 DEBUG(dbgs() << "DotDebugLoc Pair:\n"
1266 << "\t" << *Begin << "\t" << *End << "\n");
1267 if (End->isDebugValue())
1268 SLabel = getLabelBeforeInsn(End);
1270 // End is a normal instruction clobbering the range.
1271 SLabel = getLabelAfterInsn(End);
1272 assert(SLabel && "Forgot label after clobber instruction");
1277 // The value is valid until the next DBG_VALUE or clobber.
1278 DebugLocEntry Loc(FLabel, SLabel, getDebugLocValue(Begin), TheCU);
1279 if (DebugLoc.empty() || !DebugLoc.back().Merge(Loc))
1280 DebugLoc.push_back(std::move(Loc));
1284 // Collect info for variables that were optimized out.
1285 DIArray Variables = DISubprogram(FnScope->getScopeNode()).getVariables();
1286 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1287 DIVariable DV(Variables.getElement(i));
1288 if (!DV || !DV.isVariable() || !Processed.insert(DV))
1290 if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext()))
1291 addScopeVariable(Scope, new DbgVariable(DV, nullptr, this));
1295 // Return Label preceding the instruction.
1296 MCSymbol *DwarfDebug::getLabelBeforeInsn(const MachineInstr *MI) {
1297 MCSymbol *Label = LabelsBeforeInsn.lookup(MI);
1298 assert(Label && "Didn't insert label before instruction");
1302 // Return Label immediately following the instruction.
1303 MCSymbol *DwarfDebug::getLabelAfterInsn(const MachineInstr *MI) {
1304 return LabelsAfterInsn.lookup(MI);
1307 // Process beginning of an instruction.
1308 void DwarfDebug::beginInstruction(const MachineInstr *MI) {
1309 assert(CurMI == nullptr);
1311 // Check if source location changes, but ignore DBG_VALUE locations.
1312 if (!MI->isDebugValue()) {
1313 DebugLoc DL = MI->getDebugLoc();
1314 if (DL != PrevInstLoc && (!DL.isUnknown() || UnknownLocations)) {
1317 if (DL == PrologEndLoc) {
1318 Flags |= DWARF2_FLAG_PROLOGUE_END;
1319 PrologEndLoc = DebugLoc();
1321 if (PrologEndLoc.isUnknown())
1322 Flags |= DWARF2_FLAG_IS_STMT;
1324 if (!DL.isUnknown()) {
1325 const MDNode *Scope = DL.getScope(Asm->MF->getFunction()->getContext());
1326 recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags);
1328 recordSourceLine(0, 0, nullptr, 0);
1332 // Insert labels where requested.
1333 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1334 LabelsBeforeInsn.find(MI);
1337 if (I == LabelsBeforeInsn.end())
1340 // Label already assigned.
1345 PrevLabel = MMI->getContext().CreateTempSymbol();
1346 Asm->OutStreamer.EmitLabel(PrevLabel);
1348 I->second = PrevLabel;
1351 // Process end of an instruction.
1352 void DwarfDebug::endInstruction() {
1353 assert(CurMI != nullptr);
1354 // Don't create a new label after DBG_VALUE instructions.
1355 // They don't generate code.
1356 if (!CurMI->isDebugValue())
1357 PrevLabel = nullptr;
1359 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1360 LabelsAfterInsn.find(CurMI);
1364 if (I == LabelsAfterInsn.end())
1367 // Label already assigned.
1371 // We need a label after this instruction.
1373 PrevLabel = MMI->getContext().CreateTempSymbol();
1374 Asm->OutStreamer.EmitLabel(PrevLabel);
1376 I->second = PrevLabel;
1379 // Each LexicalScope has first instruction and last instruction to mark
1380 // beginning and end of a scope respectively. Create an inverse map that list
1381 // scopes starts (and ends) with an instruction. One instruction may start (or
1382 // end) multiple scopes. Ignore scopes that are not reachable.
1383 void DwarfDebug::identifyScopeMarkers() {
1384 SmallVector<LexicalScope *, 4> WorkList;
1385 WorkList.push_back(LScopes.getCurrentFunctionScope());
1386 while (!WorkList.empty()) {
1387 LexicalScope *S = WorkList.pop_back_val();
1389 const SmallVectorImpl<LexicalScope *> &Children = S->getChildren();
1390 if (!Children.empty())
1391 WorkList.append(Children.begin(), Children.end());
1393 if (S->isAbstractScope())
1396 for (const InsnRange &R : S->getRanges()) {
1397 assert(R.first && "InsnRange does not have first instruction!");
1398 assert(R.second && "InsnRange does not have second instruction!");
1399 requestLabelBeforeInsn(R.first);
1400 requestLabelAfterInsn(R.second);
1405 // Gather pre-function debug information. Assumes being called immediately
1406 // after the function entry point has been emitted.
1407 void DwarfDebug::beginFunction(const MachineFunction *MF) {
1410 // If there's no debug info for the function we're not going to do anything.
1411 if (!MMI->hasDebugInfo())
1414 // Grab the lexical scopes for the function, if we don't have any of those
1415 // then we're not going to be able to do anything.
1416 LScopes.initialize(*MF);
1417 if (LScopes.empty())
1420 assert(UserVariables.empty() && DbgValues.empty() && "Maps weren't cleaned");
1422 // Make sure that each lexical scope will have a begin/end label.
1423 identifyScopeMarkers();
1425 // Set DwarfDwarfCompileUnitID in MCContext to the Compile Unit this function
1426 // belongs to so that we add to the correct per-cu line table in the
1428 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1429 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1430 assert(TheCU && "Unable to find compile unit!");
1431 if (Asm->OutStreamer.hasRawTextSupport())
1432 // Use a single line table if we are generating assembly.
1433 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1435 Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID());
1437 // Emit a label for the function so that we have a beginning address.
1438 FunctionBeginSym = Asm->GetTempSymbol("func_begin", Asm->getFunctionNumber());
1439 // Assumes in correct section after the entry point.
1440 Asm->OutStreamer.EmitLabel(FunctionBeginSym);
1442 // Collect user variables, find the end of the prologue.
1443 for (const auto &MBB : *MF) {
1444 for (MachineBasicBlock::const_iterator II = MBB.begin(), IE = MBB.end();
1446 const MachineInstr *MI = II;
1447 if (MI->isDebugValue()) {
1448 assert(MI->getNumOperands() > 1 && "Invalid machine instruction!");
1449 // Keep track of user variables in order of appearance. Store the set
1450 // of variables we've already seen as a set of keys in DbgValues.
1451 const MDNode *Var = MI->getDebugVariable();
1452 auto IterPair = DbgValues.insert(
1453 std::make_pair(Var, SmallVector<const MachineInstr *, 4>()));
1454 if (IterPair.second)
1455 UserVariables.push_back(Var);
1456 } else if (!MI->getFlag(MachineInstr::FrameSetup) &&
1457 PrologEndLoc.isUnknown() && !MI->getDebugLoc().isUnknown()) {
1458 // First known non-DBG_VALUE and non-frame setup location marks
1459 // the beginning of the function body.
1460 PrologEndLoc = MI->getDebugLoc();
1465 // Calculate history for local variables.
1466 calculateDbgValueHistory(MF, Asm->TM.getRegisterInfo(), DbgValues);
1468 // Request labels for the full history.
1469 for (auto &I : DbgValues) {
1470 const SmallVectorImpl<const MachineInstr *> &History = I.second;
1471 if (History.empty())
1474 // The first mention of a function argument gets the FunctionBeginSym
1475 // label, so arguments are visible when breaking at function entry.
1476 DIVariable DV(I.first);
1477 if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable &&
1478 getDISubprogram(DV.getContext()).describes(MF->getFunction()))
1479 LabelsBeforeInsn[History.front()] = FunctionBeginSym;
1481 for (const MachineInstr *MI : History) {
1482 if (MI->isDebugValue())
1483 requestLabelBeforeInsn(MI);
1485 requestLabelAfterInsn(MI);
1489 PrevInstLoc = DebugLoc();
1490 PrevLabel = FunctionBeginSym;
1492 // Record beginning of function.
1493 if (!PrologEndLoc.isUnknown()) {
1494 DebugLoc FnStartDL =
1495 PrologEndLoc.getFnDebugLoc(MF->getFunction()->getContext());
1497 FnStartDL.getLine(), FnStartDL.getCol(),
1498 FnStartDL.getScope(MF->getFunction()->getContext()),
1499 // We'd like to list the prologue as "not statements" but GDB behaves
1500 // poorly if we do that. Revisit this with caution/GDB (7.5+) testing.
1501 DWARF2_FLAG_IS_STMT);
1505 void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) {
1506 SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS];
1507 DIVariable DV = Var->getVariable();
1508 // Variables with positive arg numbers are parameters.
1509 if (unsigned ArgNum = DV.getArgNumber()) {
1510 // Keep all parameters in order at the start of the variable list to ensure
1511 // function types are correct (no out-of-order parameters)
1513 // This could be improved by only doing it for optimized builds (unoptimized
1514 // builds have the right order to begin with), searching from the back (this
1515 // would catch the unoptimized case quickly), or doing a binary search
1516 // rather than linear search.
1517 SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin();
1518 while (I != Vars.end()) {
1519 unsigned CurNum = (*I)->getVariable().getArgNumber();
1520 // A local (non-parameter) variable has been found, insert immediately
1524 // A later indexed parameter has been found, insert immediately before it.
1525 if (CurNum > ArgNum)
1529 Vars.insert(I, Var);
1533 Vars.push_back(Var);
1536 // Gather and emit post-function debug information.
1537 void DwarfDebug::endFunction(const MachineFunction *MF) {
1538 // Every beginFunction(MF) call should be followed by an endFunction(MF) call,
1539 // though the beginFunction may not be called at all.
1540 // We should handle both cases.
1544 assert(CurFn == MF);
1545 assert(CurFn != nullptr);
1547 if (!MMI->hasDebugInfo() || LScopes.empty()) {
1548 // If we don't have a lexical scope for this function then there will
1549 // be a hole in the range information. Keep note of this by setting the
1550 // previously used section to nullptr.
1551 PrevSection = nullptr;
1557 // Define end label for subprogram.
1558 FunctionEndSym = Asm->GetTempSymbol("func_end", Asm->getFunctionNumber());
1559 // Assumes in correct section after the entry point.
1560 Asm->OutStreamer.EmitLabel(FunctionEndSym);
1562 // Set DwarfDwarfCompileUnitID in MCContext to default value.
1563 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1565 SmallPtrSet<const MDNode *, 16> ProcessedVars;
1566 collectVariableInfo(ProcessedVars);
1568 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1569 DwarfCompileUnit &TheCU = *SPMap.lookup(FnScope->getScopeNode());
1571 // Construct abstract scopes.
1572 for (LexicalScope *AScope : LScopes.getAbstractScopesList()) {
1573 DISubprogram SP(AScope->getScopeNode());
1574 if (SP.isSubprogram()) {
1575 // Collect info for variables that were optimized out.
1576 DIArray Variables = SP.getVariables();
1577 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1578 DIVariable DV(Variables.getElement(i));
1579 if (!DV || !DV.isVariable() || !ProcessedVars.insert(DV))
1581 // Check that DbgVariable for DV wasn't created earlier, when
1582 // findAbstractVariable() was called for inlined instance of DV.
1583 LLVMContext &Ctx = DV->getContext();
1584 DIVariable CleanDV = cleanseInlinedVariable(DV, Ctx);
1585 if (AbstractVariables.lookup(CleanDV))
1587 if (LexicalScope *Scope = LScopes.findAbstractScope(DV.getContext()))
1588 addScopeVariable(Scope, new DbgVariable(DV, nullptr, this));
1591 if (ProcessedSPNodes.count(AScope->getScopeNode()) == 0)
1592 constructAbstractSubprogramScopeDIE(TheCU, AScope);
1595 DIE &CurFnDIE = constructSubprogramScopeDIE(TheCU, FnScope);
1596 if (!CurFn->getTarget().Options.DisableFramePointerElim(*CurFn))
1597 TheCU.addFlag(CurFnDIE, dwarf::DW_AT_APPLE_omit_frame_ptr);
1599 // Add the range of this function to the list of ranges for the CU.
1600 RangeSpan Span(FunctionBeginSym, FunctionEndSym);
1601 TheCU.addRange(std::move(Span));
1602 PrevSection = Asm->getCurrentSection();
1606 for (auto &I : ScopeVariables)
1607 DeleteContainerPointers(I.second);
1608 ScopeVariables.clear();
1609 DeleteContainerPointers(CurrentFnArguments);
1610 UserVariables.clear();
1612 AbstractVariables.clear();
1613 LabelsBeforeInsn.clear();
1614 LabelsAfterInsn.clear();
1615 PrevLabel = nullptr;
1619 // Register a source line with debug info. Returns the unique label that was
1620 // emitted and which provides correspondence to the source line list.
1621 void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S,
1626 unsigned Discriminator = 0;
1628 DIDescriptor Scope(S);
1630 if (Scope.isCompileUnit()) {
1631 DICompileUnit CU(S);
1632 Fn = CU.getFilename();
1633 Dir = CU.getDirectory();
1634 } else if (Scope.isFile()) {
1636 Fn = F.getFilename();
1637 Dir = F.getDirectory();
1638 } else if (Scope.isSubprogram()) {
1640 Fn = SP.getFilename();
1641 Dir = SP.getDirectory();
1642 } else if (Scope.isLexicalBlockFile()) {
1643 DILexicalBlockFile DBF(S);
1644 Fn = DBF.getFilename();
1645 Dir = DBF.getDirectory();
1646 } else if (Scope.isLexicalBlock()) {
1647 DILexicalBlock DB(S);
1648 Fn = DB.getFilename();
1649 Dir = DB.getDirectory();
1650 Discriminator = DB.getDiscriminator();
1652 llvm_unreachable("Unexpected scope info");
1654 unsigned CUID = Asm->OutStreamer.getContext().getDwarfCompileUnitID();
1655 Src = static_cast<DwarfCompileUnit &>(*InfoHolder.getUnits()[CUID])
1656 .getOrCreateSourceID(Fn, Dir);
1658 Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0,
1662 //===----------------------------------------------------------------------===//
1664 //===----------------------------------------------------------------------===//
1666 // Emit initial Dwarf sections with a label at the start of each one.
1667 void DwarfDebug::emitSectionLabels() {
1668 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
1670 // Dwarf sections base addresses.
1671 DwarfInfoSectionSym =
1672 emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info");
1673 if (useSplitDwarf())
1674 DwarfInfoDWOSectionSym =
1675 emitSectionSym(Asm, TLOF.getDwarfInfoDWOSection(), "section_info_dwo");
1676 DwarfAbbrevSectionSym =
1677 emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev");
1678 if (useSplitDwarf())
1679 DwarfAbbrevDWOSectionSym = emitSectionSym(
1680 Asm, TLOF.getDwarfAbbrevDWOSection(), "section_abbrev_dwo");
1681 if (GenerateARangeSection)
1682 emitSectionSym(Asm, TLOF.getDwarfARangesSection());
1684 DwarfLineSectionSym =
1685 emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line");
1686 if (GenerateGnuPubSections) {
1687 DwarfGnuPubNamesSectionSym =
1688 emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection());
1689 DwarfGnuPubTypesSectionSym =
1690 emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection());
1691 } else if (HasDwarfPubSections) {
1692 emitSectionSym(Asm, TLOF.getDwarfPubNamesSection());
1693 emitSectionSym(Asm, TLOF.getDwarfPubTypesSection());
1696 DwarfStrSectionSym =
1697 emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string");
1698 if (useSplitDwarf()) {
1699 DwarfStrDWOSectionSym =
1700 emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string");
1701 DwarfAddrSectionSym =
1702 emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec");
1703 DwarfDebugLocSectionSym =
1704 emitSectionSym(Asm, TLOF.getDwarfLocDWOSection(), "skel_loc");
1706 DwarfDebugLocSectionSym =
1707 emitSectionSym(Asm, TLOF.getDwarfLocSection(), "section_debug_loc");
1708 DwarfDebugRangeSectionSym =
1709 emitSectionSym(Asm, TLOF.getDwarfRangesSection(), "debug_range");
1712 // Recursively emits a debug information entry.
1713 void DwarfDebug::emitDIE(DIE &Die) {
1714 // Get the abbreviation for this DIE.
1715 const DIEAbbrev &Abbrev = Die.getAbbrev();
1717 // Emit the code (index) for the abbreviation.
1718 if (Asm->isVerbose())
1719 Asm->OutStreamer.AddComment("Abbrev [" + Twine(Abbrev.getNumber()) +
1720 "] 0x" + Twine::utohexstr(Die.getOffset()) +
1721 ":0x" + Twine::utohexstr(Die.getSize()) + " " +
1722 dwarf::TagString(Abbrev.getTag()));
1723 Asm->EmitULEB128(Abbrev.getNumber());
1725 const SmallVectorImpl<DIEValue *> &Values = Die.getValues();
1726 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
1728 // Emit the DIE attribute values.
1729 for (unsigned i = 0, N = Values.size(); i < N; ++i) {
1730 dwarf::Attribute Attr = AbbrevData[i].getAttribute();
1731 dwarf::Form Form = AbbrevData[i].getForm();
1732 assert(Form && "Too many attributes for DIE (check abbreviation)");
1734 if (Asm->isVerbose()) {
1735 Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr));
1736 if (Attr == dwarf::DW_AT_accessibility)
1737 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(
1738 cast<DIEInteger>(Values[i])->getValue()));
1741 // Emit an attribute using the defined form.
1742 Values[i]->EmitValue(Asm, Form);
1745 // Emit the DIE children if any.
1746 if (Abbrev.hasChildren()) {
1747 for (auto &Child : Die.getChildren())
1750 Asm->OutStreamer.AddComment("End Of Children Mark");
1755 // Emit the debug info section.
1756 void DwarfDebug::emitDebugInfo() {
1757 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1759 Holder.emitUnits(this, DwarfAbbrevSectionSym);
1762 // Emit the abbreviation section.
1763 void DwarfDebug::emitAbbreviations() {
1764 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1766 Holder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection());
1769 // Emit the last address of the section and the end of the line matrix.
1770 void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) {
1771 // Define last address of section.
1772 Asm->OutStreamer.AddComment("Extended Op");
1775 Asm->OutStreamer.AddComment("Op size");
1776 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1);
1777 Asm->OutStreamer.AddComment("DW_LNE_set_address");
1778 Asm->EmitInt8(dwarf::DW_LNE_set_address);
1780 Asm->OutStreamer.AddComment("Section end label");
1782 Asm->OutStreamer.EmitSymbolValue(
1783 Asm->GetTempSymbol("section_end", SectionEnd),
1784 Asm->getDataLayout().getPointerSize());
1786 // Mark end of matrix.
1787 Asm->OutStreamer.AddComment("DW_LNE_end_sequence");
1793 // Emit visible names into a hashed accelerator table section.
1794 void DwarfDebug::emitAccelNames() {
1795 AccelNames.FinalizeTable(Asm, "Names");
1796 Asm->OutStreamer.SwitchSection(
1797 Asm->getObjFileLowering().getDwarfAccelNamesSection());
1798 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin");
1799 Asm->OutStreamer.EmitLabel(SectionBegin);
1801 // Emit the full data.
1802 AccelNames.Emit(Asm, SectionBegin, &InfoHolder);
1805 // Emit objective C classes and categories into a hashed accelerator table
1807 void DwarfDebug::emitAccelObjC() {
1808 AccelObjC.FinalizeTable(Asm, "ObjC");
1809 Asm->OutStreamer.SwitchSection(
1810 Asm->getObjFileLowering().getDwarfAccelObjCSection());
1811 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin");
1812 Asm->OutStreamer.EmitLabel(SectionBegin);
1814 // Emit the full data.
1815 AccelObjC.Emit(Asm, SectionBegin, &InfoHolder);
1818 // Emit namespace dies into a hashed accelerator table.
1819 void DwarfDebug::emitAccelNamespaces() {
1820 AccelNamespace.FinalizeTable(Asm, "namespac");
1821 Asm->OutStreamer.SwitchSection(
1822 Asm->getObjFileLowering().getDwarfAccelNamespaceSection());
1823 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin");
1824 Asm->OutStreamer.EmitLabel(SectionBegin);
1826 // Emit the full data.
1827 AccelNamespace.Emit(Asm, SectionBegin, &InfoHolder);
1830 // Emit type dies into a hashed accelerator table.
1831 void DwarfDebug::emitAccelTypes() {
1833 AccelTypes.FinalizeTable(Asm, "types");
1834 Asm->OutStreamer.SwitchSection(
1835 Asm->getObjFileLowering().getDwarfAccelTypesSection());
1836 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin");
1837 Asm->OutStreamer.EmitLabel(SectionBegin);
1839 // Emit the full data.
1840 AccelTypes.Emit(Asm, SectionBegin, &InfoHolder);
1843 // Public name handling.
1844 // The format for the various pubnames:
1846 // dwarf pubnames - offset/name pairs where the offset is the offset into the CU
1847 // for the DIE that is named.
1849 // gnu pubnames - offset/index value/name tuples where the offset is the offset
1850 // into the CU and the index value is computed according to the type of value
1851 // for the DIE that is named.
1853 // For type units the offset is the offset of the skeleton DIE. For split dwarf
1854 // it's the offset within the debug_info/debug_types dwo section, however, the
1855 // reference in the pubname header doesn't change.
1857 /// computeIndexValue - Compute the gdb index value for the DIE and CU.
1858 static dwarf::PubIndexEntryDescriptor computeIndexValue(DwarfUnit *CU,
1860 dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC;
1862 // We could have a specification DIE that has our most of our knowledge,
1863 // look for that now.
1864 DIEValue *SpecVal = Die->findAttribute(dwarf::DW_AT_specification);
1866 DIE &SpecDIE = cast<DIEEntry>(SpecVal)->getEntry();
1867 if (SpecDIE.findAttribute(dwarf::DW_AT_external))
1868 Linkage = dwarf::GIEL_EXTERNAL;
1869 } else if (Die->findAttribute(dwarf::DW_AT_external))
1870 Linkage = dwarf::GIEL_EXTERNAL;
1872 switch (Die->getTag()) {
1873 case dwarf::DW_TAG_class_type:
1874 case dwarf::DW_TAG_structure_type:
1875 case dwarf::DW_TAG_union_type:
1876 case dwarf::DW_TAG_enumeration_type:
1877 return dwarf::PubIndexEntryDescriptor(
1878 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus
1879 ? dwarf::GIEL_STATIC
1880 : dwarf::GIEL_EXTERNAL);
1881 case dwarf::DW_TAG_typedef:
1882 case dwarf::DW_TAG_base_type:
1883 case dwarf::DW_TAG_subrange_type:
1884 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC);
1885 case dwarf::DW_TAG_namespace:
1886 return dwarf::GIEK_TYPE;
1887 case dwarf::DW_TAG_subprogram:
1888 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage);
1889 case dwarf::DW_TAG_constant:
1890 case dwarf::DW_TAG_variable:
1891 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage);
1892 case dwarf::DW_TAG_enumerator:
1893 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE,
1894 dwarf::GIEL_STATIC);
1896 return dwarf::GIEK_NONE;
1900 /// emitDebugPubNames - Emit visible names into a debug pubnames section.
1902 void DwarfDebug::emitDebugPubNames(bool GnuStyle) {
1903 const MCSection *PSec =
1904 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection()
1905 : Asm->getObjFileLowering().getDwarfPubNamesSection();
1907 emitDebugPubSection(GnuStyle, PSec, "Names", &DwarfUnit::getGlobalNames);
1910 void DwarfDebug::emitDebugPubSection(
1911 bool GnuStyle, const MCSection *PSec, StringRef Name,
1912 const StringMap<const DIE *> &(DwarfUnit::*Accessor)() const) {
1913 for (const auto &NU : CUMap) {
1914 DwarfCompileUnit *TheU = NU.second;
1916 const auto &Globals = (TheU->*Accessor)();
1918 if (Globals.empty())
1921 if (auto Skeleton = static_cast<DwarfCompileUnit *>(TheU->getSkeleton()))
1923 unsigned ID = TheU->getUniqueID();
1925 // Start the dwarf pubnames section.
1926 Asm->OutStreamer.SwitchSection(PSec);
1929 Asm->OutStreamer.AddComment("Length of Public " + Name + " Info");
1930 MCSymbol *BeginLabel = Asm->GetTempSymbol("pub" + Name + "_begin", ID);
1931 MCSymbol *EndLabel = Asm->GetTempSymbol("pub" + Name + "_end", ID);
1932 Asm->EmitLabelDifference(EndLabel, BeginLabel, 4);
1934 Asm->OutStreamer.EmitLabel(BeginLabel);
1936 Asm->OutStreamer.AddComment("DWARF Version");
1937 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION);
1939 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info");
1940 Asm->EmitSectionOffset(TheU->getLabelBegin(), TheU->getSectionSym());
1942 Asm->OutStreamer.AddComment("Compilation Unit Length");
1943 Asm->EmitLabelDifference(TheU->getLabelEnd(), TheU->getLabelBegin(), 4);
1945 // Emit the pubnames for this compilation unit.
1946 for (const auto &GI : Globals) {
1947 const char *Name = GI.getKeyData();
1948 const DIE *Entity = GI.second;
1950 Asm->OutStreamer.AddComment("DIE offset");
1951 Asm->EmitInt32(Entity->getOffset());
1954 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheU, Entity);
1955 Asm->OutStreamer.AddComment(
1956 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " +
1957 dwarf::GDBIndexEntryLinkageString(Desc.Linkage));
1958 Asm->EmitInt8(Desc.toBits());
1961 Asm->OutStreamer.AddComment("External Name");
1962 Asm->OutStreamer.EmitBytes(StringRef(Name, GI.getKeyLength() + 1));
1965 Asm->OutStreamer.AddComment("End Mark");
1967 Asm->OutStreamer.EmitLabel(EndLabel);
1971 void DwarfDebug::emitDebugPubTypes(bool GnuStyle) {
1972 const MCSection *PSec =
1973 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection()
1974 : Asm->getObjFileLowering().getDwarfPubTypesSection();
1976 emitDebugPubSection(GnuStyle, PSec, "Types", &DwarfUnit::getGlobalTypes);
1979 // Emit visible names into a debug str section.
1980 void DwarfDebug::emitDebugStr() {
1981 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1982 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection());
1985 void DwarfDebug::emitDebugLocEntry(ByteStreamer &Streamer,
1986 const DebugLocEntry &Entry) {
1987 assert(Entry.getValues().size() == 1 &&
1988 "multi-value entries are not supported yet.");
1989 const DebugLocEntry::Value Value = Entry.getValues()[0];
1990 DIVariable DV(Value.getVariable());
1991 if (Value.isInt()) {
1992 DIBasicType BTy(resolve(DV.getType()));
1993 if (BTy.Verify() && (BTy.getEncoding() == dwarf::DW_ATE_signed ||
1994 BTy.getEncoding() == dwarf::DW_ATE_signed_char)) {
1995 Streamer.EmitInt8(dwarf::DW_OP_consts, "DW_OP_consts");
1996 Streamer.EmitSLEB128(Value.getInt());
1998 Streamer.EmitInt8(dwarf::DW_OP_constu, "DW_OP_constu");
1999 Streamer.EmitULEB128(Value.getInt());
2001 } else if (Value.isLocation()) {
2002 MachineLocation Loc = Value.getLoc();
2003 if (!DV.hasComplexAddress())
2005 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2007 // Complex address entry.
2008 unsigned N = DV.getNumAddrElements();
2010 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) {
2011 if (Loc.getOffset()) {
2013 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2014 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
2015 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
2016 Streamer.EmitSLEB128(DV.getAddrElement(1));
2018 // If first address element is OpPlus then emit
2019 // DW_OP_breg + Offset instead of DW_OP_reg + Offset.
2020 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1));
2021 Asm->EmitDwarfRegOp(Streamer, TLoc, DV.isIndirect());
2025 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2028 // Emit remaining complex address elements.
2029 for (; i < N; ++i) {
2030 uint64_t Element = DV.getAddrElement(i);
2031 if (Element == DIBuilder::OpPlus) {
2032 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
2033 Streamer.EmitULEB128(DV.getAddrElement(++i));
2034 } else if (Element == DIBuilder::OpDeref) {
2036 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
2038 llvm_unreachable("unknown Opcode found in complex address");
2042 // else ... ignore constant fp. There is not any good way to
2043 // to represent them here in dwarf.
2047 void DwarfDebug::emitDebugLocEntryLocation(const DebugLocEntry &Entry) {
2048 Asm->OutStreamer.AddComment("Loc expr size");
2049 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol();
2050 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol();
2051 Asm->EmitLabelDifference(end, begin, 2);
2052 Asm->OutStreamer.EmitLabel(begin);
2054 APByteStreamer Streamer(*Asm);
2055 emitDebugLocEntry(Streamer, Entry);
2057 Asm->OutStreamer.EmitLabel(end);
2060 // Emit locations into the debug loc section.
2061 void DwarfDebug::emitDebugLoc() {
2062 // Start the dwarf loc section.
2063 Asm->OutStreamer.SwitchSection(
2064 Asm->getObjFileLowering().getDwarfLocSection());
2065 unsigned char Size = Asm->getDataLayout().getPointerSize();
2066 for (const auto &DebugLoc : DotDebugLocEntries) {
2067 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2068 for (const auto &Entry : DebugLoc.List) {
2069 // Set up the range. This range is relative to the entry point of the
2070 // compile unit. This is a hard coded 0 for low_pc when we're emitting
2071 // ranges, or the DW_AT_low_pc on the compile unit otherwise.
2072 const DwarfCompileUnit *CU = Entry.getCU();
2073 if (CU->getRanges().size() == 1) {
2074 // Grab the begin symbol from the first range as our base.
2075 const MCSymbol *Base = CU->getRanges()[0].getStart();
2076 Asm->EmitLabelDifference(Entry.getBeginSym(), Base, Size);
2077 Asm->EmitLabelDifference(Entry.getEndSym(), Base, Size);
2079 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size);
2080 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size);
2083 emitDebugLocEntryLocation(Entry);
2085 Asm->OutStreamer.EmitIntValue(0, Size);
2086 Asm->OutStreamer.EmitIntValue(0, Size);
2090 void DwarfDebug::emitDebugLocDWO() {
2091 Asm->OutStreamer.SwitchSection(
2092 Asm->getObjFileLowering().getDwarfLocDWOSection());
2093 for (const auto &DebugLoc : DotDebugLocEntries) {
2094 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2095 for (const auto &Entry : DebugLoc.List) {
2096 // Just always use start_length for now - at least that's one address
2097 // rather than two. We could get fancier and try to, say, reuse an
2098 // address we know we've emitted elsewhere (the start of the function?
2099 // The start of the CU or CU subrange that encloses this range?)
2100 Asm->EmitInt8(dwarf::DW_LLE_start_length_entry);
2101 unsigned idx = AddrPool.getIndex(Entry.getBeginSym());
2102 Asm->EmitULEB128(idx);
2103 Asm->EmitLabelDifference(Entry.getEndSym(), Entry.getBeginSym(), 4);
2105 emitDebugLocEntryLocation(Entry);
2107 Asm->EmitInt8(dwarf::DW_LLE_end_of_list_entry);
2112 const MCSymbol *Start, *End;
2115 // Emit a debug aranges section, containing a CU lookup for any
2116 // address we can tie back to a CU.
2117 void DwarfDebug::emitDebugARanges() {
2118 // Start the dwarf aranges section.
2119 Asm->OutStreamer.SwitchSection(
2120 Asm->getObjFileLowering().getDwarfARangesSection());
2122 typedef DenseMap<DwarfCompileUnit *, std::vector<ArangeSpan>> SpansType;
2126 // Build a list of sections used.
2127 std::vector<const MCSection *> Sections;
2128 for (const auto &it : SectionMap) {
2129 const MCSection *Section = it.first;
2130 Sections.push_back(Section);
2133 // Sort the sections into order.
2134 // This is only done to ensure consistent output order across different runs.
2135 std::sort(Sections.begin(), Sections.end(), SectionSort);
2137 // Build a set of address spans, sorted by CU.
2138 for (const MCSection *Section : Sections) {
2139 SmallVector<SymbolCU, 8> &List = SectionMap[Section];
2140 if (List.size() < 2)
2143 // Sort the symbols by offset within the section.
2144 std::sort(List.begin(), List.end(),
2145 [&](const SymbolCU &A, const SymbolCU &B) {
2146 unsigned IA = A.Sym ? Asm->OutStreamer.GetSymbolOrder(A.Sym) : 0;
2147 unsigned IB = B.Sym ? Asm->OutStreamer.GetSymbolOrder(B.Sym) : 0;
2149 // Symbols with no order assigned should be placed at the end.
2150 // (e.g. section end labels)
2158 // If we have no section (e.g. common), just write out
2159 // individual spans for each symbol.
2161 for (const SymbolCU &Cur : List) {
2163 Span.Start = Cur.Sym;
2166 Spans[Cur.CU].push_back(Span);
2169 // Build spans between each label.
2170 const MCSymbol *StartSym = List[0].Sym;
2171 for (size_t n = 1, e = List.size(); n < e; n++) {
2172 const SymbolCU &Prev = List[n - 1];
2173 const SymbolCU &Cur = List[n];
2175 // Try and build the longest span we can within the same CU.
2176 if (Cur.CU != Prev.CU) {
2178 Span.Start = StartSym;
2180 Spans[Prev.CU].push_back(Span);
2187 unsigned PtrSize = Asm->getDataLayout().getPointerSize();
2189 // Build a list of CUs used.
2190 std::vector<DwarfCompileUnit *> CUs;
2191 for (const auto &it : Spans) {
2192 DwarfCompileUnit *CU = it.first;
2196 // Sort the CU list (again, to ensure consistent output order).
2197 std::sort(CUs.begin(), CUs.end(), [](const DwarfUnit *A, const DwarfUnit *B) {
2198 return A->getUniqueID() < B->getUniqueID();
2201 // Emit an arange table for each CU we used.
2202 for (DwarfCompileUnit *CU : CUs) {
2203 std::vector<ArangeSpan> &List = Spans[CU];
2205 // Emit size of content not including length itself.
2206 unsigned ContentSize =
2207 sizeof(int16_t) + // DWARF ARange version number
2208 sizeof(int32_t) + // Offset of CU in the .debug_info section
2209 sizeof(int8_t) + // Pointer Size (in bytes)
2210 sizeof(int8_t); // Segment Size (in bytes)
2212 unsigned TupleSize = PtrSize * 2;
2214 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple.
2216 OffsetToAlignment(sizeof(int32_t) + ContentSize, TupleSize);
2218 ContentSize += Padding;
2219 ContentSize += (List.size() + 1) * TupleSize;
2221 // For each compile unit, write the list of spans it covers.
2222 Asm->OutStreamer.AddComment("Length of ARange Set");
2223 Asm->EmitInt32(ContentSize);
2224 Asm->OutStreamer.AddComment("DWARF Arange version number");
2225 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION);
2226 Asm->OutStreamer.AddComment("Offset Into Debug Info Section");
2227 Asm->EmitSectionOffset(CU->getLocalLabelBegin(), CU->getLocalSectionSym());
2228 Asm->OutStreamer.AddComment("Address Size (in bytes)");
2229 Asm->EmitInt8(PtrSize);
2230 Asm->OutStreamer.AddComment("Segment Size (in bytes)");
2233 Asm->OutStreamer.EmitFill(Padding, 0xff);
2235 for (const ArangeSpan &Span : List) {
2236 Asm->EmitLabelReference(Span.Start, PtrSize);
2238 // Calculate the size as being from the span start to it's end.
2240 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize);
2242 // For symbols without an end marker (e.g. common), we
2243 // write a single arange entry containing just that one symbol.
2244 uint64_t Size = SymSize[Span.Start];
2248 Asm->OutStreamer.EmitIntValue(Size, PtrSize);
2252 Asm->OutStreamer.AddComment("ARange terminator");
2253 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2254 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2258 // Emit visible names into a debug ranges section.
2259 void DwarfDebug::emitDebugRanges() {
2260 // Start the dwarf ranges section.
2261 Asm->OutStreamer.SwitchSection(
2262 Asm->getObjFileLowering().getDwarfRangesSection());
2264 // Size for our labels.
2265 unsigned char Size = Asm->getDataLayout().getPointerSize();
2267 // Grab the specific ranges for the compile units in the module.
2268 for (const auto &I : CUMap) {
2269 DwarfCompileUnit *TheCU = I.second;
2271 // Iterate over the misc ranges for the compile units in the module.
2272 for (const RangeSpanList &List : TheCU->getRangeLists()) {
2273 // Emit our symbol so we can find the beginning of the range.
2274 Asm->OutStreamer.EmitLabel(List.getSym());
2276 for (const RangeSpan &Range : List.getRanges()) {
2277 const MCSymbol *Begin = Range.getStart();
2278 const MCSymbol *End = Range.getEnd();
2279 assert(Begin && "Range without a begin symbol?");
2280 assert(End && "Range without an end symbol?");
2281 if (TheCU->getRanges().size() == 1) {
2282 // Grab the begin symbol from the first range as our base.
2283 const MCSymbol *Base = TheCU->getRanges()[0].getStart();
2284 Asm->EmitLabelDifference(Begin, Base, Size);
2285 Asm->EmitLabelDifference(End, Base, Size);
2287 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2288 Asm->OutStreamer.EmitSymbolValue(End, Size);
2292 // And terminate the list with two 0 values.
2293 Asm->OutStreamer.EmitIntValue(0, Size);
2294 Asm->OutStreamer.EmitIntValue(0, Size);
2297 // Now emit a range for the CU itself.
2298 if (TheCU->getRanges().size() > 1) {
2299 Asm->OutStreamer.EmitLabel(
2300 Asm->GetTempSymbol("cu_ranges", TheCU->getUniqueID()));
2301 for (const RangeSpan &Range : TheCU->getRanges()) {
2302 const MCSymbol *Begin = Range.getStart();
2303 const MCSymbol *End = Range.getEnd();
2304 assert(Begin && "Range without a begin symbol?");
2305 assert(End && "Range without an end symbol?");
2306 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2307 Asm->OutStreamer.EmitSymbolValue(End, Size);
2309 // And terminate the list with two 0 values.
2310 Asm->OutStreamer.EmitIntValue(0, Size);
2311 Asm->OutStreamer.EmitIntValue(0, Size);
2316 // DWARF5 Experimental Separate Dwarf emitters.
2318 void DwarfDebug::initSkeletonUnit(const DwarfUnit &U, DIE &Die,
2319 std::unique_ptr<DwarfUnit> NewU) {
2320 NewU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name,
2321 U.getCUNode().getSplitDebugFilename());
2323 if (!CompilationDir.empty())
2324 NewU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
2326 addGnuPubAttributes(*NewU, Die);
2328 SkeletonHolder.addUnit(std::move(NewU));
2331 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list,
2332 // DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id,
2333 // DW_AT_addr_base, DW_AT_ranges_base.
2334 DwarfCompileUnit &DwarfDebug::constructSkeletonCU(const DwarfCompileUnit &CU) {
2336 auto OwnedUnit = make_unique<DwarfCompileUnit>(
2337 CU.getUniqueID(), CU.getCUNode(), Asm, this, &SkeletonHolder);
2338 DwarfCompileUnit &NewCU = *OwnedUnit;
2339 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
2340 DwarfInfoSectionSym);
2342 NewCU.initStmtList(DwarfLineSectionSym);
2344 initSkeletonUnit(CU, NewCU.getUnitDie(), std::move(OwnedUnit));
2349 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_dwo_name,
2351 DwarfTypeUnit &DwarfDebug::constructSkeletonTU(DwarfTypeUnit &TU) {
2352 DwarfCompileUnit &CU = static_cast<DwarfCompileUnit &>(
2353 *SkeletonHolder.getUnits()[TU.getCU().getUniqueID()]);
2355 auto OwnedUnit = make_unique<DwarfTypeUnit>(TU.getUniqueID(), CU, Asm, this,
2357 DwarfTypeUnit &NewTU = *OwnedUnit;
2358 NewTU.setTypeSignature(TU.getTypeSignature());
2359 NewTU.setType(nullptr);
2361 Asm->getObjFileLowering().getDwarfTypesSection(TU.getTypeSignature()));
2363 initSkeletonUnit(TU, NewTU.getUnitDie(), std::move(OwnedUnit));
2367 // Emit the .debug_info.dwo section for separated dwarf. This contains the
2368 // compile units that would normally be in debug_info.
2369 void DwarfDebug::emitDebugInfoDWO() {
2370 assert(useSplitDwarf() && "No split dwarf debug info?");
2371 // Don't pass an abbrev symbol, using a constant zero instead so as not to
2372 // emit relocations into the dwo file.
2373 InfoHolder.emitUnits(this, /* AbbrevSymbol */ nullptr);
2376 // Emit the .debug_abbrev.dwo section for separated dwarf. This contains the
2377 // abbreviations for the .debug_info.dwo section.
2378 void DwarfDebug::emitDebugAbbrevDWO() {
2379 assert(useSplitDwarf() && "No split dwarf?");
2380 InfoHolder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection());
2383 void DwarfDebug::emitDebugLineDWO() {
2384 assert(useSplitDwarf() && "No split dwarf?");
2385 Asm->OutStreamer.SwitchSection(
2386 Asm->getObjFileLowering().getDwarfLineDWOSection());
2387 SplitTypeUnitFileTable.Emit(Asm->OutStreamer);
2390 // Emit the .debug_str.dwo section for separated dwarf. This contains the
2391 // string section and is identical in format to traditional .debug_str
2393 void DwarfDebug::emitDebugStrDWO() {
2394 assert(useSplitDwarf() && "No split dwarf?");
2395 const MCSection *OffSec =
2396 Asm->getObjFileLowering().getDwarfStrOffDWOSection();
2397 const MCSymbol *StrSym = DwarfStrSectionSym;
2398 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(),
2402 MCDwarfDwoLineTable *DwarfDebug::getDwoLineTable(const DwarfCompileUnit &CU) {
2403 if (!useSplitDwarf())
2406 SplitTypeUnitFileTable.setCompilationDir(CU.getCUNode().getDirectory());
2407 return &SplitTypeUnitFileTable;
2410 static uint64_t makeTypeSignature(StringRef Identifier) {
2412 Hash.update(Identifier);
2413 // ... take the least significant 8 bytes and return those. Our MD5
2414 // implementation always returns its results in little endian, swap bytes
2416 MD5::MD5Result Result;
2418 return *reinterpret_cast<support::ulittle64_t *>(Result + 8);
2421 void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU,
2422 StringRef Identifier, DIE &RefDie,
2423 DICompositeType CTy) {
2424 // Fast path if we're building some type units and one has already used the
2425 // address pool we know we're going to throw away all this work anyway, so
2426 // don't bother building dependent types.
2427 if (!TypeUnitsUnderConstruction.empty() && AddrPool.hasBeenUsed())
2430 const DwarfTypeUnit *&TU = DwarfTypeUnits[CTy];
2432 CU.addDIETypeSignature(RefDie, *TU);
2436 bool TopLevelType = TypeUnitsUnderConstruction.empty();
2437 AddrPool.resetUsedFlag();
2440 make_unique<DwarfTypeUnit>(InfoHolder.getUnits().size(), CU, Asm, this,
2441 &InfoHolder, getDwoLineTable(CU));
2442 DwarfTypeUnit &NewTU = *OwnedUnit;
2443 DIE &UnitDie = NewTU.getUnitDie();
2445 TypeUnitsUnderConstruction.push_back(
2446 std::make_pair(std::move(OwnedUnit), CTy));
2448 NewTU.addUInt(UnitDie, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
2451 uint64_t Signature = makeTypeSignature(Identifier);
2452 NewTU.setTypeSignature(Signature);
2454 if (!useSplitDwarf())
2455 CU.applyStmtList(UnitDie);
2459 ? Asm->getObjFileLowering().getDwarfTypesDWOSection(Signature)
2460 : Asm->getObjFileLowering().getDwarfTypesSection(Signature));
2462 NewTU.setType(NewTU.createTypeDIE(CTy));
2465 auto TypeUnitsToAdd = std::move(TypeUnitsUnderConstruction);
2466 TypeUnitsUnderConstruction.clear();
2468 // Types referencing entries in the address table cannot be placed in type
2470 if (AddrPool.hasBeenUsed()) {
2472 // Remove all the types built while building this type.
2473 // This is pessimistic as some of these types might not be dependent on
2474 // the type that used an address.
2475 for (const auto &TU : TypeUnitsToAdd)
2476 DwarfTypeUnits.erase(TU.second);
2478 // Construct this type in the CU directly.
2479 // This is inefficient because all the dependent types will be rebuilt
2480 // from scratch, including building them in type units, discovering that
2481 // they depend on addresses, throwing them out and rebuilding them.
2482 CU.constructTypeDIE(RefDie, CTy);
2486 // If the type wasn't dependent on fission addresses, finish adding the type
2487 // and all its dependent types.
2488 for (auto &TU : TypeUnitsToAdd) {
2489 if (useSplitDwarf())
2490 TU.first->setSkeleton(constructSkeletonTU(*TU.first));
2491 InfoHolder.addUnit(std::move(TU.first));
2494 CU.addDIETypeSignature(RefDie, NewTU);
2497 void DwarfDebug::attachLowHighPC(DwarfCompileUnit &Unit, DIE &D,
2498 MCSymbol *Begin, MCSymbol *End) {
2499 Unit.addLabelAddress(D, dwarf::DW_AT_low_pc, Begin);
2500 if (DwarfVersion < 4)
2501 Unit.addLabelAddress(D, dwarf::DW_AT_high_pc, End);
2503 Unit.addLabelDelta(D, dwarf::DW_AT_high_pc, End, Begin);
2506 // Accelerator table mutators - add each name along with its companion
2507 // DIE to the proper table while ensuring that the name that we're going
2508 // to reference is in the string table. We do this since the names we
2509 // add may not only be identical to the names in the DIE.
2510 void DwarfDebug::addAccelName(StringRef Name, const DIE &Die) {
2511 if (!useDwarfAccelTables())
2513 AccelNames.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2517 void DwarfDebug::addAccelObjC(StringRef Name, const DIE &Die) {
2518 if (!useDwarfAccelTables())
2520 AccelObjC.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2524 void DwarfDebug::addAccelNamespace(StringRef Name, const DIE &Die) {
2525 if (!useDwarfAccelTables())
2527 AccelNamespace.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2531 void DwarfDebug::addAccelType(StringRef Name, const DIE &Die, char Flags) {
2532 if (!useDwarfAccelTables())
2534 AccelTypes.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),