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 static std::unique_ptr<DIE> constructVariableDIE(DwarfCompileUnit &TheCU,
514 const LexicalScope &Scope,
515 DIE *&ObjectPointer) {
516 AbstractOrInlined AOI = AOI_None;
517 if (Scope.isAbstractScope())
519 else if (Scope.getInlinedAt())
521 auto Var = TheCU.constructVariableDIE(DV, AOI);
522 if (DV.isObjectPointer())
523 ObjectPointer = Var.get();
527 DIE *DwarfDebug::createScopeChildrenDIE(
528 DwarfCompileUnit &TheCU, LexicalScope *Scope,
529 SmallVectorImpl<std::unique_ptr<DIE>> &Children) {
530 DIE *ObjectPointer = nullptr;
532 // Collect arguments for current function.
533 if (LScopes.isCurrentFunctionScope(Scope)) {
534 for (DbgVariable *ArgDV : CurrentFnArguments)
537 constructVariableDIE(TheCU, *ArgDV, *Scope, ObjectPointer));
539 // If this is a variadic function, add an unspecified parameter.
540 DISubprogram SP(Scope->getScopeNode());
541 DIArray FnArgs = SP.getType().getTypeArray();
542 if (FnArgs.getElement(FnArgs.getNumElements() - 1)
543 .isUnspecifiedParameter()) {
545 make_unique<DIE>(dwarf::DW_TAG_unspecified_parameters));
549 // Collect lexical scope children first.
550 for (DbgVariable *DV : ScopeVariables.lookup(Scope))
551 Children.push_back(constructVariableDIE(TheCU, *DV, *Scope, ObjectPointer));
553 for (LexicalScope *LS : Scope->getChildren())
554 if (std::unique_ptr<DIE> Nested = constructScopeDIE(TheCU, LS))
555 Children.push_back(std::move(Nested));
556 return ObjectPointer;
559 void DwarfDebug::createAndAddScopeChildren(DwarfCompileUnit &TheCU,
560 LexicalScope *Scope, DIE &ScopeDIE) {
561 // We create children when the scope DIE is not null.
562 SmallVector<std::unique_ptr<DIE>, 8> Children;
563 if (DIE *ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children))
564 TheCU.addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, *ObjectPointer);
567 for (auto &I : Children)
568 ScopeDIE.addChild(std::move(I));
571 void DwarfDebug::constructAbstractSubprogramScopeDIE(DwarfCompileUnit &TheCU,
572 LexicalScope *Scope) {
573 assert(Scope && Scope->getScopeNode());
574 assert(Scope->isAbstractScope());
575 assert(!Scope->getInlinedAt());
577 DISubprogram Sub(Scope->getScopeNode());
579 ProcessedSPNodes.insert(Sub);
581 if (DIE *ScopeDIE = TheCU.getDIE(Sub)) {
582 AbstractSPDies.insert(std::make_pair(Sub, ScopeDIE));
583 createAndAddScopeChildren(TheCU, Scope, *ScopeDIE);
587 DIE &DwarfDebug::constructSubprogramScopeDIE(DwarfCompileUnit &TheCU,
588 LexicalScope *Scope) {
589 assert(Scope && Scope->getScopeNode());
590 assert(!Scope->getInlinedAt());
591 assert(!Scope->isAbstractScope());
592 assert(DIScope(Scope->getScopeNode()).isSubprogram());
594 DISubprogram Sub(Scope->getScopeNode());
596 ProcessedSPNodes.insert(Sub);
598 DIE &ScopeDIE = updateSubprogramScopeDIE(TheCU, Sub);
600 createAndAddScopeChildren(TheCU, Scope, ScopeDIE);
605 // Construct a DIE for this scope.
606 std::unique_ptr<DIE> DwarfDebug::constructScopeDIE(DwarfCompileUnit &TheCU,
607 LexicalScope *Scope) {
608 if (!Scope || !Scope->getScopeNode())
611 DIScope DS(Scope->getScopeNode());
613 assert((Scope->getInlinedAt() || !DS.isSubprogram()) &&
614 "Only handle inlined subprograms here, use "
615 "constructSubprogramScopeDIE for non-inlined "
618 SmallVector<std::unique_ptr<DIE>, 8> Children;
620 // We try to create the scope DIE first, then the children DIEs. This will
621 // avoid creating un-used children then removing them later when we find out
622 // the scope DIE is null.
623 std::unique_ptr<DIE> ScopeDIE;
624 if (Scope->getInlinedAt()) {
625 ScopeDIE = constructInlinedScopeDIE(TheCU, Scope);
628 // We create children when the scope DIE is not null.
629 createScopeChildrenDIE(TheCU, Scope, Children);
631 // Early exit when we know the scope DIE is going to be null.
632 if (isLexicalScopeDIENull(Scope))
635 // We create children here when we know the scope DIE is not going to be
636 // null and the children will be added to the scope DIE.
637 createScopeChildrenDIE(TheCU, Scope, Children);
639 // There is no need to emit empty lexical block DIE.
640 std::pair<ImportedEntityMap::const_iterator,
641 ImportedEntityMap::const_iterator> Range =
642 std::equal_range(ScopesWithImportedEntities.begin(),
643 ScopesWithImportedEntities.end(),
644 std::pair<const MDNode *, const MDNode *>(DS, nullptr),
646 if (Children.empty() && Range.first == Range.second)
648 ScopeDIE = constructLexicalScopeDIE(TheCU, Scope);
649 assert(ScopeDIE && "Scope DIE should not be null.");
650 for (ImportedEntityMap::const_iterator i = Range.first; i != Range.second;
652 constructImportedEntityDIE(TheCU, i->second, *ScopeDIE);
656 for (auto &I : Children)
657 ScopeDIE->addChild(std::move(I));
662 void DwarfDebug::addGnuPubAttributes(DwarfUnit &U, DIE &D) const {
663 if (!GenerateGnuPubSections)
666 U.addFlag(D, dwarf::DW_AT_GNU_pubnames);
669 // Create new DwarfCompileUnit for the given metadata node with tag
670 // DW_TAG_compile_unit.
671 DwarfCompileUnit &DwarfDebug::constructDwarfCompileUnit(DICompileUnit DIUnit) {
672 StringRef FN = DIUnit.getFilename();
673 CompilationDir = DIUnit.getDirectory();
675 auto OwnedUnit = make_unique<DwarfCompileUnit>(
676 InfoHolder.getUnits().size(), DIUnit, Asm, this, &InfoHolder);
677 DwarfCompileUnit &NewCU = *OwnedUnit;
678 DIE &Die = NewCU.getUnitDie();
679 InfoHolder.addUnit(std::move(OwnedUnit));
681 // LTO with assembly output shares a single line table amongst multiple CUs.
682 // To avoid the compilation directory being ambiguous, let the line table
683 // explicitly describe the directory of all files, never relying on the
684 // compilation directory.
685 if (!Asm->OutStreamer.hasRawTextSupport() || SingleCU)
686 Asm->OutStreamer.getContext().setMCLineTableCompilationDir(
687 NewCU.getUniqueID(), CompilationDir);
689 NewCU.addString(Die, dwarf::DW_AT_producer, DIUnit.getProducer());
690 NewCU.addUInt(Die, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
691 DIUnit.getLanguage());
692 NewCU.addString(Die, dwarf::DW_AT_name, FN);
694 if (!useSplitDwarf()) {
695 NewCU.initStmtList(DwarfLineSectionSym);
697 // If we're using split dwarf the compilation dir is going to be in the
698 // skeleton CU and so we don't need to duplicate it here.
699 if (!CompilationDir.empty())
700 NewCU.addString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
702 addGnuPubAttributes(NewCU, Die);
705 if (DIUnit.isOptimized())
706 NewCU.addFlag(Die, dwarf::DW_AT_APPLE_optimized);
708 StringRef Flags = DIUnit.getFlags();
710 NewCU.addString(Die, dwarf::DW_AT_APPLE_flags, Flags);
712 if (unsigned RVer = DIUnit.getRunTimeVersion())
713 NewCU.addUInt(Die, dwarf::DW_AT_APPLE_major_runtime_vers,
714 dwarf::DW_FORM_data1, RVer);
719 if (useSplitDwarf()) {
720 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoDWOSection(),
721 DwarfInfoDWOSectionSym);
722 NewCU.setSkeleton(constructSkeletonCU(NewCU));
724 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
725 DwarfInfoSectionSym);
727 CUMap.insert(std::make_pair(DIUnit, &NewCU));
728 CUDieMap.insert(std::make_pair(&Die, &NewCU));
732 // Construct subprogram DIE.
733 void DwarfDebug::constructSubprogramDIE(DwarfCompileUnit &TheCU,
735 // FIXME: We should only call this routine once, however, during LTO if a
736 // program is defined in multiple CUs we could end up calling it out of
737 // beginModule as we walk the CUs.
739 DwarfCompileUnit *&CURef = SPMap[N];
745 if (!SP.isDefinition())
746 // This is a method declaration which will be handled while constructing
750 DIE &SubprogramDie = *TheCU.getOrCreateSubprogramDIE(SP);
752 // Expose as a global name.
753 TheCU.addGlobalName(SP.getName(), SubprogramDie, resolve(SP.getContext()));
756 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
758 DIImportedEntity Module(N);
759 assert(Module.Verify());
760 if (DIE *D = TheCU.getOrCreateContextDIE(Module.getContext()))
761 constructImportedEntityDIE(TheCU, Module, *D);
764 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
765 const MDNode *N, DIE &Context) {
766 DIImportedEntity Module(N);
767 assert(Module.Verify());
768 return constructImportedEntityDIE(TheCU, Module, Context);
771 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
772 const DIImportedEntity &Module,
774 assert(Module.Verify() &&
775 "Use one of the MDNode * overloads to handle invalid metadata");
776 DIE &IMDie = TheCU.createAndAddDIE(Module.getTag(), Context, Module);
778 DIDescriptor Entity = resolve(Module.getEntity());
779 if (Entity.isNameSpace())
780 EntityDie = TheCU.getOrCreateNameSpace(DINameSpace(Entity));
781 else if (Entity.isSubprogram())
782 EntityDie = TheCU.getOrCreateSubprogramDIE(DISubprogram(Entity));
783 else if (Entity.isType())
784 EntityDie = TheCU.getOrCreateTypeDIE(DIType(Entity));
786 EntityDie = TheCU.getDIE(Entity);
787 TheCU.addSourceLine(IMDie, Module.getLineNumber(),
788 Module.getContext().getFilename(),
789 Module.getContext().getDirectory());
790 TheCU.addDIEEntry(IMDie, dwarf::DW_AT_import, *EntityDie);
791 StringRef Name = Module.getName();
793 TheCU.addString(IMDie, dwarf::DW_AT_name, Name);
796 // Emit all Dwarf sections that should come prior to the content. Create
797 // global DIEs and emit initial debug info sections. This is invoked by
798 // the target AsmPrinter.
799 void DwarfDebug::beginModule() {
800 if (DisableDebugInfoPrinting)
803 const Module *M = MMI->getModule();
805 // If module has named metadata anchors then use them, otherwise scan the
806 // module using debug info finder to collect debug info.
807 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
810 TypeIdentifierMap = generateDITypeIdentifierMap(CU_Nodes);
812 // Emit initial sections so we can reference labels later.
815 SingleCU = CU_Nodes->getNumOperands() == 1;
817 for (MDNode *N : CU_Nodes->operands()) {
818 DICompileUnit CUNode(N);
819 DwarfCompileUnit &CU = constructDwarfCompileUnit(CUNode);
820 DIArray ImportedEntities = CUNode.getImportedEntities();
821 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
822 ScopesWithImportedEntities.push_back(std::make_pair(
823 DIImportedEntity(ImportedEntities.getElement(i)).getContext(),
824 ImportedEntities.getElement(i)));
825 std::sort(ScopesWithImportedEntities.begin(),
826 ScopesWithImportedEntities.end(), less_first());
827 DIArray GVs = CUNode.getGlobalVariables();
828 for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i)
829 CU.createGlobalVariableDIE(DIGlobalVariable(GVs.getElement(i)));
830 DIArray SPs = CUNode.getSubprograms();
831 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i)
832 constructSubprogramDIE(CU, SPs.getElement(i));
833 DIArray EnumTypes = CUNode.getEnumTypes();
834 for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i)
835 CU.getOrCreateTypeDIE(EnumTypes.getElement(i));
836 DIArray RetainedTypes = CUNode.getRetainedTypes();
837 for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i) {
838 DIType Ty(RetainedTypes.getElement(i));
839 // The retained types array by design contains pointers to
840 // MDNodes rather than DIRefs. Unique them here.
841 DIType UniqueTy(resolve(Ty.getRef()));
842 CU.getOrCreateTypeDIE(UniqueTy);
844 // Emit imported_modules last so that the relevant context is already
846 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
847 constructImportedEntityDIE(CU, ImportedEntities.getElement(i));
850 // Tell MMI that we have debug info.
851 MMI->setDebugInfoAvailability(true);
853 // Prime section data.
854 SectionMap[Asm->getObjFileLowering().getTextSection()];
857 // Attach DW_AT_inline attribute with inlined subprogram DIEs.
858 void DwarfDebug::computeInlinedDIEs() {
859 // Attach DW_AT_inline attribute with inlined subprogram DIEs.
860 for (DIE *ISP : InlinedSubprogramDIEs)
861 FirstCU->addUInt(*ISP, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined);
863 for (const auto &AI : AbstractSPDies) {
864 DIE &ISP = *AI.second;
865 if (InlinedSubprogramDIEs.count(&ISP))
867 FirstCU->addUInt(ISP, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined);
871 // Collect info for variables that were optimized out.
872 void DwarfDebug::collectDeadVariables() {
873 const Module *M = MMI->getModule();
875 if (NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu")) {
876 for (MDNode *N : CU_Nodes->operands()) {
877 DICompileUnit TheCU(N);
878 DIArray Subprograms = TheCU.getSubprograms();
879 for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) {
880 DISubprogram SP(Subprograms.getElement(i));
881 if (ProcessedSPNodes.count(SP) != 0)
883 if (!SP.isSubprogram())
885 if (!SP.isDefinition())
887 DIArray Variables = SP.getVariables();
888 if (Variables.getNumElements() == 0)
891 // Construct subprogram DIE and add variables DIEs.
892 DwarfCompileUnit *SPCU =
893 static_cast<DwarfCompileUnit *>(CUMap.lookup(TheCU));
894 assert(SPCU && "Unable to find Compile Unit!");
895 // FIXME: See the comment in constructSubprogramDIE about duplicate
897 constructSubprogramDIE(*SPCU, SP);
898 DIE *SPDIE = SPCU->getDIE(SP);
899 for (unsigned vi = 0, ve = Variables.getNumElements(); vi != ve; ++vi) {
900 DIVariable DV(Variables.getElement(vi));
901 if (!DV.isVariable())
903 DbgVariable NewVar(DV, nullptr, this);
904 SPDIE->addChild(SPCU->constructVariableDIE(NewVar));
911 void DwarfDebug::finalizeModuleInfo() {
912 // Collect info for variables that were optimized out.
913 collectDeadVariables();
915 // Attach DW_AT_inline attribute with inlined subprogram DIEs.
916 computeInlinedDIEs();
918 // Handle anything that needs to be done on a per-unit basis after
919 // all other generation.
920 for (const auto &TheU : getUnits()) {
921 // Emit DW_AT_containing_type attribute to connect types with their
922 // vtable holding type.
923 TheU->constructContainingTypeDIEs();
925 // Add CU specific attributes if we need to add any.
926 if (TheU->getUnitDie().getTag() == dwarf::DW_TAG_compile_unit) {
927 // If we're splitting the dwarf out now that we've got the entire
928 // CU then add the dwo id to it.
929 DwarfCompileUnit *SkCU =
930 static_cast<DwarfCompileUnit *>(TheU->getSkeleton());
931 if (useSplitDwarf()) {
932 // Emit a unique identifier for this CU.
933 uint64_t ID = DIEHash(Asm).computeCUSignature(TheU->getUnitDie());
934 TheU->addUInt(TheU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
935 dwarf::DW_FORM_data8, ID);
936 SkCU->addUInt(SkCU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
937 dwarf::DW_FORM_data8, ID);
939 // We don't keep track of which addresses are used in which CU so this
940 // is a bit pessimistic under LTO.
941 if (!AddrPool.isEmpty())
942 addSectionLabel(*Asm, *SkCU, SkCU->getUnitDie(),
943 dwarf::DW_AT_GNU_addr_base, DwarfAddrSectionSym,
944 DwarfAddrSectionSym);
945 if (!TheU->getRangeLists().empty())
946 addSectionLabel(*Asm, *SkCU, SkCU->getUnitDie(),
947 dwarf::DW_AT_GNU_ranges_base,
948 DwarfDebugRangeSectionSym, DwarfDebugRangeSectionSym);
951 // If we have code split among multiple sections or non-contiguous
952 // ranges of code then emit a DW_AT_ranges attribute on the unit that will
953 // remain in the .o file, otherwise add a DW_AT_low_pc.
954 // FIXME: We should use ranges allow reordering of code ala
955 // .subsections_via_symbols in mach-o. This would mean turning on
956 // ranges for all subprogram DIEs for mach-o.
957 DwarfCompileUnit &U =
958 SkCU ? *SkCU : static_cast<DwarfCompileUnit &>(*TheU);
959 unsigned NumRanges = TheU->getRanges().size();
962 addSectionLabel(*Asm, U, U.getUnitDie(), dwarf::DW_AT_ranges,
963 Asm->GetTempSymbol("cu_ranges", U.getUniqueID()),
964 DwarfDebugRangeSectionSym);
966 // A DW_AT_low_pc attribute may also be specified in combination with
967 // DW_AT_ranges to specify the default base address for use in
968 // location lists (see Section 2.6.2) and range lists (see Section
970 U.addUInt(U.getUnitDie(), dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr,
973 RangeSpan &Range = TheU->getRanges().back();
974 U.addLocalLabelAddress(U.getUnitDie(), dwarf::DW_AT_low_pc,
976 U.addLabelDelta(U.getUnitDie(), dwarf::DW_AT_high_pc, Range.getEnd(),
983 // Compute DIE offsets and sizes.
984 InfoHolder.computeSizeAndOffsets();
986 SkeletonHolder.computeSizeAndOffsets();
989 void DwarfDebug::endSections() {
990 // Filter labels by section.
991 for (const SymbolCU &SCU : ArangeLabels) {
992 if (SCU.Sym->isInSection()) {
993 // Make a note of this symbol and it's section.
994 const MCSection *Section = &SCU.Sym->getSection();
995 if (!Section->getKind().isMetadata())
996 SectionMap[Section].push_back(SCU);
998 // Some symbols (e.g. common/bss on mach-o) can have no section but still
999 // appear in the output. This sucks as we rely on sections to build
1000 // arange spans. We can do it without, but it's icky.
1001 SectionMap[nullptr].push_back(SCU);
1005 // Build a list of sections used.
1006 std::vector<const MCSection *> Sections;
1007 for (const auto &it : SectionMap) {
1008 const MCSection *Section = it.first;
1009 Sections.push_back(Section);
1012 // Sort the sections into order.
1013 // This is only done to ensure consistent output order across different runs.
1014 std::sort(Sections.begin(), Sections.end(), SectionSort);
1016 // Add terminating symbols for each section.
1017 for (unsigned ID = 0, E = Sections.size(); ID != E; ID++) {
1018 const MCSection *Section = Sections[ID];
1019 MCSymbol *Sym = nullptr;
1022 // We can't call MCSection::getLabelEndName, as it's only safe to do so
1023 // if we know the section name up-front. For user-created sections, the
1024 // resulting label may not be valid to use as a label. (section names can
1025 // use a greater set of characters on some systems)
1026 Sym = Asm->GetTempSymbol("debug_end", ID);
1027 Asm->OutStreamer.SwitchSection(Section);
1028 Asm->OutStreamer.EmitLabel(Sym);
1031 // Insert a final terminator.
1032 SectionMap[Section].push_back(SymbolCU(nullptr, Sym));
1036 // Emit all Dwarf sections that should come after the content.
1037 void DwarfDebug::endModule() {
1038 assert(CurFn == nullptr);
1039 assert(CurMI == nullptr);
1044 // End any existing sections.
1045 // TODO: Does this need to happen?
1048 // Finalize the debug info for the module.
1049 finalizeModuleInfo();
1053 // Emit all the DIEs into a debug info section.
1056 // Corresponding abbreviations into a abbrev section.
1057 emitAbbreviations();
1059 // Emit info into a debug aranges section.
1060 if (GenerateARangeSection)
1063 // Emit info into a debug ranges section.
1066 if (useSplitDwarf()) {
1069 emitDebugAbbrevDWO();
1071 // Emit DWO addresses.
1072 AddrPool.emit(*Asm, Asm->getObjFileLowering().getDwarfAddrSection());
1075 // Emit info into a debug loc section.
1078 // Emit info into the dwarf accelerator table sections.
1079 if (useDwarfAccelTables()) {
1082 emitAccelNamespaces();
1086 // Emit the pubnames and pubtypes sections if requested.
1087 if (HasDwarfPubSections) {
1088 emitDebugPubNames(GenerateGnuPubSections);
1089 emitDebugPubTypes(GenerateGnuPubSections);
1095 // Reset these for the next Module if we have one.
1099 // Find abstract variable, if any, associated with Var.
1100 DbgVariable *DwarfDebug::findAbstractVariable(DIVariable &DV,
1101 DebugLoc ScopeLoc) {
1102 LLVMContext &Ctx = DV->getContext();
1103 // More then one inlined variable corresponds to one abstract variable.
1104 DIVariable Var = cleanseInlinedVariable(DV, Ctx);
1105 DbgVariable *AbsDbgVariable = AbstractVariables.lookup(Var);
1107 return AbsDbgVariable;
1109 LexicalScope *Scope = LScopes.findAbstractScope(ScopeLoc.getScope(Ctx));
1113 AbsDbgVariable = new DbgVariable(Var, nullptr, this);
1114 addScopeVariable(Scope, AbsDbgVariable);
1115 AbstractVariables[Var] = AbsDbgVariable;
1116 return AbsDbgVariable;
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 DbgVariable *AbsDbgVariable = findAbstractVariable(DV, VI.Loc);
1156 DbgVariable *RegVar = new DbgVariable(DV, AbsDbgVariable, this);
1157 RegVar->setFrameIndex(VI.Slot);
1158 if (!addCurrentFnArgument(RegVar, Scope))
1159 addScopeVariable(Scope, RegVar);
1161 AbsDbgVariable->setFrameIndex(VI.Slot);
1165 // Get .debug_loc entry for the instruction range starting at MI.
1166 static DebugLocEntry::Value getDebugLocValue(const MachineInstr *MI) {
1167 const MDNode *Var = MI->getDebugVariable();
1169 assert(MI->getNumOperands() == 3);
1170 if (MI->getOperand(0).isReg()) {
1171 MachineLocation MLoc;
1172 // If the second operand is an immediate, this is a
1173 // register-indirect address.
1174 if (!MI->getOperand(1).isImm())
1175 MLoc.set(MI->getOperand(0).getReg());
1177 MLoc.set(MI->getOperand(0).getReg(), MI->getOperand(1).getImm());
1178 return DebugLocEntry::Value(Var, MLoc);
1180 if (MI->getOperand(0).isImm())
1181 return DebugLocEntry::Value(Var, MI->getOperand(0).getImm());
1182 if (MI->getOperand(0).isFPImm())
1183 return DebugLocEntry::Value(Var, MI->getOperand(0).getFPImm());
1184 if (MI->getOperand(0).isCImm())
1185 return DebugLocEntry::Value(Var, MI->getOperand(0).getCImm());
1187 llvm_unreachable("Unexpected 3 operand DBG_VALUE instruction!");
1190 // Find variables for each lexical scope.
1192 DwarfDebug::collectVariableInfo(SmallPtrSet<const MDNode *, 16> &Processed) {
1193 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1194 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1196 // Grab the variable info that was squirreled away in the MMI side-table.
1197 collectVariableInfoFromMMITable(Processed);
1199 for (const auto &I : DbgValues) {
1200 DIVariable DV(I.first);
1201 if (Processed.count(DV))
1204 // History contains relevant DBG_VALUE instructions for DV and instructions
1206 const SmallVectorImpl<const MachineInstr *> &History = I.second;
1207 if (History.empty())
1209 const MachineInstr *MInsn = History.front();
1211 LexicalScope *Scope = nullptr;
1212 if (DV.getTag() == dwarf::DW_TAG_arg_variable &&
1213 DISubprogram(DV.getContext()).describes(CurFn->getFunction()))
1214 Scope = LScopes.getCurrentFunctionScope();
1215 else if (MDNode *IA = DV.getInlinedAt())
1216 Scope = LScopes.findInlinedScope(DebugLoc::getFromDILocation(IA));
1218 Scope = LScopes.findLexicalScope(cast<MDNode>(DV->getOperand(1)));
1219 // If variable scope is not found then skip this variable.
1223 Processed.insert(DV);
1224 assert(MInsn->isDebugValue() && "History must begin with debug value");
1225 DbgVariable *AbsVar = findAbstractVariable(DV, MInsn->getDebugLoc());
1226 DbgVariable *RegVar = new DbgVariable(DV, AbsVar, this);
1227 if (!addCurrentFnArgument(RegVar, Scope))
1228 addScopeVariable(Scope, RegVar);
1230 AbsVar->setMInsn(MInsn);
1232 // Simplify ranges that are fully coalesced.
1233 if (History.size() <= 1 ||
1234 (History.size() == 2 && MInsn->isIdenticalTo(History.back()))) {
1235 RegVar->setMInsn(MInsn);
1239 // Handle multiple DBG_VALUE instructions describing one variable.
1240 RegVar->setDotDebugLocOffset(DotDebugLocEntries.size());
1242 DotDebugLocEntries.resize(DotDebugLocEntries.size() + 1);
1243 DebugLocList &LocList = DotDebugLocEntries.back();
1245 Asm->GetTempSymbol("debug_loc", DotDebugLocEntries.size() - 1);
1246 SmallVector<DebugLocEntry, 4> &DebugLoc = LocList.List;
1247 for (SmallVectorImpl<const MachineInstr *>::const_iterator
1248 HI = History.begin(),
1251 const MachineInstr *Begin = *HI;
1252 assert(Begin->isDebugValue() && "Invalid History entry");
1254 // Check if DBG_VALUE is truncating a range.
1255 if (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() &&
1256 !Begin->getOperand(0).getReg())
1259 // Compute the range for a register location.
1260 const MCSymbol *FLabel = getLabelBeforeInsn(Begin);
1261 const MCSymbol *SLabel = nullptr;
1264 // If Begin is the last instruction in History then its value is valid
1265 // until the end of the function.
1266 SLabel = FunctionEndSym;
1268 const MachineInstr *End = HI[1];
1269 DEBUG(dbgs() << "DotDebugLoc Pair:\n"
1270 << "\t" << *Begin << "\t" << *End << "\n");
1271 if (End->isDebugValue())
1272 SLabel = getLabelBeforeInsn(End);
1274 // End is a normal instruction clobbering the range.
1275 SLabel = getLabelAfterInsn(End);
1276 assert(SLabel && "Forgot label after clobber instruction");
1281 // The value is valid until the next DBG_VALUE or clobber.
1282 DebugLocEntry Loc(FLabel, SLabel, getDebugLocValue(Begin), TheCU);
1283 if (DebugLoc.empty() || !DebugLoc.back().Merge(Loc))
1284 DebugLoc.push_back(std::move(Loc));
1288 // Collect info for variables that were optimized out.
1289 DIArray Variables = DISubprogram(FnScope->getScopeNode()).getVariables();
1290 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1291 DIVariable DV(Variables.getElement(i));
1292 if (!DV || !DV.isVariable() || !Processed.insert(DV))
1294 if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext()))
1295 addScopeVariable(Scope, new DbgVariable(DV, nullptr, this));
1299 // Return Label preceding the instruction.
1300 MCSymbol *DwarfDebug::getLabelBeforeInsn(const MachineInstr *MI) {
1301 MCSymbol *Label = LabelsBeforeInsn.lookup(MI);
1302 assert(Label && "Didn't insert label before instruction");
1306 // Return Label immediately following the instruction.
1307 MCSymbol *DwarfDebug::getLabelAfterInsn(const MachineInstr *MI) {
1308 return LabelsAfterInsn.lookup(MI);
1311 // Process beginning of an instruction.
1312 void DwarfDebug::beginInstruction(const MachineInstr *MI) {
1313 assert(CurMI == nullptr);
1315 // Check if source location changes, but ignore DBG_VALUE locations.
1316 if (!MI->isDebugValue()) {
1317 DebugLoc DL = MI->getDebugLoc();
1318 if (DL != PrevInstLoc && (!DL.isUnknown() || UnknownLocations)) {
1321 if (DL == PrologEndLoc) {
1322 Flags |= DWARF2_FLAG_PROLOGUE_END;
1323 PrologEndLoc = DebugLoc();
1325 if (PrologEndLoc.isUnknown())
1326 Flags |= DWARF2_FLAG_IS_STMT;
1328 if (!DL.isUnknown()) {
1329 const MDNode *Scope = DL.getScope(Asm->MF->getFunction()->getContext());
1330 recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags);
1332 recordSourceLine(0, 0, nullptr, 0);
1336 // Insert labels where requested.
1337 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1338 LabelsBeforeInsn.find(MI);
1341 if (I == LabelsBeforeInsn.end())
1344 // Label already assigned.
1349 PrevLabel = MMI->getContext().CreateTempSymbol();
1350 Asm->OutStreamer.EmitLabel(PrevLabel);
1352 I->second = PrevLabel;
1355 // Process end of an instruction.
1356 void DwarfDebug::endInstruction() {
1357 assert(CurMI != nullptr);
1358 // Don't create a new label after DBG_VALUE instructions.
1359 // They don't generate code.
1360 if (!CurMI->isDebugValue())
1361 PrevLabel = nullptr;
1363 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1364 LabelsAfterInsn.find(CurMI);
1368 if (I == LabelsAfterInsn.end())
1371 // Label already assigned.
1375 // We need a label after this instruction.
1377 PrevLabel = MMI->getContext().CreateTempSymbol();
1378 Asm->OutStreamer.EmitLabel(PrevLabel);
1380 I->second = PrevLabel;
1383 // Each LexicalScope has first instruction and last instruction to mark
1384 // beginning and end of a scope respectively. Create an inverse map that list
1385 // scopes starts (and ends) with an instruction. One instruction may start (or
1386 // end) multiple scopes. Ignore scopes that are not reachable.
1387 void DwarfDebug::identifyScopeMarkers() {
1388 SmallVector<LexicalScope *, 4> WorkList;
1389 WorkList.push_back(LScopes.getCurrentFunctionScope());
1390 while (!WorkList.empty()) {
1391 LexicalScope *S = WorkList.pop_back_val();
1393 const SmallVectorImpl<LexicalScope *> &Children = S->getChildren();
1394 if (!Children.empty())
1395 WorkList.append(Children.begin(), Children.end());
1397 if (S->isAbstractScope())
1400 for (const InsnRange &R : S->getRanges()) {
1401 assert(R.first && "InsnRange does not have first instruction!");
1402 assert(R.second && "InsnRange does not have second instruction!");
1403 requestLabelBeforeInsn(R.first);
1404 requestLabelAfterInsn(R.second);
1409 // Gather pre-function debug information. Assumes being called immediately
1410 // after the function entry point has been emitted.
1411 void DwarfDebug::beginFunction(const MachineFunction *MF) {
1414 // If there's no debug info for the function we're not going to do anything.
1415 if (!MMI->hasDebugInfo())
1418 // Grab the lexical scopes for the function, if we don't have any of those
1419 // then we're not going to be able to do anything.
1420 LScopes.initialize(*MF);
1421 if (LScopes.empty())
1424 assert(DbgValues.empty() && "DbgValues map wasn't cleaned!");
1426 // Make sure that each lexical scope will have a begin/end label.
1427 identifyScopeMarkers();
1429 // Set DwarfDwarfCompileUnitID in MCContext to the Compile Unit this function
1430 // belongs to so that we add to the correct per-cu line table in the
1432 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1433 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1434 assert(TheCU && "Unable to find compile unit!");
1435 if (Asm->OutStreamer.hasRawTextSupport())
1436 // Use a single line table if we are generating assembly.
1437 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1439 Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID());
1441 // Emit a label for the function so that we have a beginning address.
1442 FunctionBeginSym = Asm->GetTempSymbol("func_begin", Asm->getFunctionNumber());
1443 // Assumes in correct section after the entry point.
1444 Asm->OutStreamer.EmitLabel(FunctionBeginSym);
1446 // Collect user variables, find the end of the prologue.
1447 for (const auto &MBB : *MF) {
1448 for (const auto &MI : MBB) {
1449 if (MI.isDebugValue()) {
1450 assert(MI.getNumOperands() > 1 && "Invalid machine instruction!");
1451 // Keep track of user variables in order of appearance. Create the
1452 // empty history for each variable so that the order of keys in
1453 // DbgValues is correct. Actual history will be populated in
1454 // calculateDbgValueHistory() function.
1455 const MDNode *Var = MI.getDebugVariable();
1457 std::make_pair(Var, SmallVector<const MachineInstr *, 4>()));
1458 } else if (!MI.getFlag(MachineInstr::FrameSetup) &&
1459 PrologEndLoc.isUnknown() && !MI.getDebugLoc().isUnknown()) {
1460 // First known non-DBG_VALUE and non-frame setup location marks
1461 // the beginning of the function body.
1462 PrologEndLoc = MI.getDebugLoc();
1467 // Calculate history for local variables.
1468 calculateDbgValueHistory(MF, Asm->TM.getRegisterInfo(), DbgValues);
1470 // Request labels for the full history.
1471 for (auto &I : DbgValues) {
1472 const SmallVectorImpl<const MachineInstr *> &History = I.second;
1473 if (History.empty())
1476 // The first mention of a function argument gets the FunctionBeginSym
1477 // label, so arguments are visible when breaking at function entry.
1478 DIVariable DV(I.first);
1479 if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable &&
1480 getDISubprogram(DV.getContext()).describes(MF->getFunction()))
1481 LabelsBeforeInsn[History.front()] = FunctionBeginSym;
1483 for (const MachineInstr *MI : History) {
1484 if (MI->isDebugValue())
1485 requestLabelBeforeInsn(MI);
1487 requestLabelAfterInsn(MI);
1491 PrevInstLoc = DebugLoc();
1492 PrevLabel = FunctionBeginSym;
1494 // Record beginning of function.
1495 if (!PrologEndLoc.isUnknown()) {
1496 DebugLoc FnStartDL =
1497 PrologEndLoc.getFnDebugLoc(MF->getFunction()->getContext());
1499 FnStartDL.getLine(), FnStartDL.getCol(),
1500 FnStartDL.getScope(MF->getFunction()->getContext()),
1501 // We'd like to list the prologue as "not statements" but GDB behaves
1502 // poorly if we do that. Revisit this with caution/GDB (7.5+) testing.
1503 DWARF2_FLAG_IS_STMT);
1507 void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) {
1508 SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS];
1509 DIVariable DV = Var->getVariable();
1510 // Variables with positive arg numbers are parameters.
1511 if (unsigned ArgNum = DV.getArgNumber()) {
1512 // Keep all parameters in order at the start of the variable list to ensure
1513 // function types are correct (no out-of-order parameters)
1515 // This could be improved by only doing it for optimized builds (unoptimized
1516 // builds have the right order to begin with), searching from the back (this
1517 // would catch the unoptimized case quickly), or doing a binary search
1518 // rather than linear search.
1519 SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin();
1520 while (I != Vars.end()) {
1521 unsigned CurNum = (*I)->getVariable().getArgNumber();
1522 // A local (non-parameter) variable has been found, insert immediately
1526 // A later indexed parameter has been found, insert immediately before it.
1527 if (CurNum > ArgNum)
1531 Vars.insert(I, Var);
1535 Vars.push_back(Var);
1538 // Gather and emit post-function debug information.
1539 void DwarfDebug::endFunction(const MachineFunction *MF) {
1540 // Every beginFunction(MF) call should be followed by an endFunction(MF) call,
1541 // though the beginFunction may not be called at all.
1542 // We should handle both cases.
1546 assert(CurFn == MF);
1547 assert(CurFn != nullptr);
1549 if (!MMI->hasDebugInfo() || LScopes.empty()) {
1550 // If we don't have a lexical scope for this function then there will
1551 // be a hole in the range information. Keep note of this by setting the
1552 // previously used section to nullptr.
1553 PrevSection = nullptr;
1559 // Define end label for subprogram.
1560 FunctionEndSym = Asm->GetTempSymbol("func_end", Asm->getFunctionNumber());
1561 // Assumes in correct section after the entry point.
1562 Asm->OutStreamer.EmitLabel(FunctionEndSym);
1564 // Set DwarfDwarfCompileUnitID in MCContext to default value.
1565 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1567 SmallPtrSet<const MDNode *, 16> ProcessedVars;
1568 collectVariableInfo(ProcessedVars);
1570 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1571 DwarfCompileUnit &TheCU = *SPMap.lookup(FnScope->getScopeNode());
1573 // Construct abstract scopes.
1574 for (LexicalScope *AScope : LScopes.getAbstractScopesList()) {
1575 DISubprogram SP(AScope->getScopeNode());
1576 if (SP.isSubprogram()) {
1577 // Collect info for variables that were optimized out.
1578 DIArray Variables = SP.getVariables();
1579 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1580 DIVariable DV(Variables.getElement(i));
1581 if (!DV || !DV.isVariable() || !ProcessedVars.insert(DV))
1583 // Check that DbgVariable for DV wasn't created earlier, when
1584 // findAbstractVariable() was called for inlined instance of DV.
1585 LLVMContext &Ctx = DV->getContext();
1586 DIVariable CleanDV = cleanseInlinedVariable(DV, Ctx);
1587 if (AbstractVariables.lookup(CleanDV))
1589 if (LexicalScope *Scope = LScopes.findAbstractScope(DV.getContext()))
1590 addScopeVariable(Scope, new DbgVariable(DV, nullptr, this));
1593 if (ProcessedSPNodes.count(AScope->getScopeNode()) == 0)
1594 constructAbstractSubprogramScopeDIE(TheCU, AScope);
1597 DIE &CurFnDIE = constructSubprogramScopeDIE(TheCU, FnScope);
1598 if (!CurFn->getTarget().Options.DisableFramePointerElim(*CurFn))
1599 TheCU.addFlag(CurFnDIE, dwarf::DW_AT_APPLE_omit_frame_ptr);
1601 // Add the range of this function to the list of ranges for the CU.
1602 RangeSpan Span(FunctionBeginSym, FunctionEndSym);
1603 TheCU.addRange(std::move(Span));
1604 PrevSection = Asm->getCurrentSection();
1608 for (auto &I : ScopeVariables)
1609 DeleteContainerPointers(I.second);
1610 ScopeVariables.clear();
1611 DeleteContainerPointers(CurrentFnArguments);
1613 AbstractVariables.clear();
1614 LabelsBeforeInsn.clear();
1615 LabelsAfterInsn.clear();
1616 PrevLabel = nullptr;
1620 // Register a source line with debug info. Returns the unique label that was
1621 // emitted and which provides correspondence to the source line list.
1622 void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S,
1627 unsigned Discriminator = 0;
1629 DIDescriptor Scope(S);
1631 if (Scope.isCompileUnit()) {
1632 DICompileUnit CU(S);
1633 Fn = CU.getFilename();
1634 Dir = CU.getDirectory();
1635 } else if (Scope.isFile()) {
1637 Fn = F.getFilename();
1638 Dir = F.getDirectory();
1639 } else if (Scope.isSubprogram()) {
1641 Fn = SP.getFilename();
1642 Dir = SP.getDirectory();
1643 } else if (Scope.isLexicalBlockFile()) {
1644 DILexicalBlockFile DBF(S);
1645 Fn = DBF.getFilename();
1646 Dir = DBF.getDirectory();
1647 } else if (Scope.isLexicalBlock()) {
1648 DILexicalBlock DB(S);
1649 Fn = DB.getFilename();
1650 Dir = DB.getDirectory();
1651 Discriminator = DB.getDiscriminator();
1653 llvm_unreachable("Unexpected scope info");
1655 unsigned CUID = Asm->OutStreamer.getContext().getDwarfCompileUnitID();
1656 Src = static_cast<DwarfCompileUnit &>(*InfoHolder.getUnits()[CUID])
1657 .getOrCreateSourceID(Fn, Dir);
1659 Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0,
1663 //===----------------------------------------------------------------------===//
1665 //===----------------------------------------------------------------------===//
1667 // Emit initial Dwarf sections with a label at the start of each one.
1668 void DwarfDebug::emitSectionLabels() {
1669 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
1671 // Dwarf sections base addresses.
1672 DwarfInfoSectionSym =
1673 emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info");
1674 if (useSplitDwarf())
1675 DwarfInfoDWOSectionSym =
1676 emitSectionSym(Asm, TLOF.getDwarfInfoDWOSection(), "section_info_dwo");
1677 DwarfAbbrevSectionSym =
1678 emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev");
1679 if (useSplitDwarf())
1680 DwarfAbbrevDWOSectionSym = emitSectionSym(
1681 Asm, TLOF.getDwarfAbbrevDWOSection(), "section_abbrev_dwo");
1682 if (GenerateARangeSection)
1683 emitSectionSym(Asm, TLOF.getDwarfARangesSection());
1685 DwarfLineSectionSym =
1686 emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line");
1687 if (GenerateGnuPubSections) {
1688 DwarfGnuPubNamesSectionSym =
1689 emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection());
1690 DwarfGnuPubTypesSectionSym =
1691 emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection());
1692 } else if (HasDwarfPubSections) {
1693 emitSectionSym(Asm, TLOF.getDwarfPubNamesSection());
1694 emitSectionSym(Asm, TLOF.getDwarfPubTypesSection());
1697 DwarfStrSectionSym =
1698 emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string");
1699 if (useSplitDwarf()) {
1700 DwarfStrDWOSectionSym =
1701 emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string");
1702 DwarfAddrSectionSym =
1703 emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec");
1704 DwarfDebugLocSectionSym =
1705 emitSectionSym(Asm, TLOF.getDwarfLocDWOSection(), "skel_loc");
1707 DwarfDebugLocSectionSym =
1708 emitSectionSym(Asm, TLOF.getDwarfLocSection(), "section_debug_loc");
1709 DwarfDebugRangeSectionSym =
1710 emitSectionSym(Asm, TLOF.getDwarfRangesSection(), "debug_range");
1713 // Recursively emits a debug information entry.
1714 void DwarfDebug::emitDIE(DIE &Die) {
1715 // Get the abbreviation for this DIE.
1716 const DIEAbbrev &Abbrev = Die.getAbbrev();
1718 // Emit the code (index) for the abbreviation.
1719 if (Asm->isVerbose())
1720 Asm->OutStreamer.AddComment("Abbrev [" + Twine(Abbrev.getNumber()) +
1721 "] 0x" + Twine::utohexstr(Die.getOffset()) +
1722 ":0x" + Twine::utohexstr(Die.getSize()) + " " +
1723 dwarf::TagString(Abbrev.getTag()));
1724 Asm->EmitULEB128(Abbrev.getNumber());
1726 const SmallVectorImpl<DIEValue *> &Values = Die.getValues();
1727 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
1729 // Emit the DIE attribute values.
1730 for (unsigned i = 0, N = Values.size(); i < N; ++i) {
1731 dwarf::Attribute Attr = AbbrevData[i].getAttribute();
1732 dwarf::Form Form = AbbrevData[i].getForm();
1733 assert(Form && "Too many attributes for DIE (check abbreviation)");
1735 if (Asm->isVerbose()) {
1736 Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr));
1737 if (Attr == dwarf::DW_AT_accessibility)
1738 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(
1739 cast<DIEInteger>(Values[i])->getValue()));
1742 // Emit an attribute using the defined form.
1743 Values[i]->EmitValue(Asm, Form);
1746 // Emit the DIE children if any.
1747 if (Abbrev.hasChildren()) {
1748 for (auto &Child : Die.getChildren())
1751 Asm->OutStreamer.AddComment("End Of Children Mark");
1756 // Emit the debug info section.
1757 void DwarfDebug::emitDebugInfo() {
1758 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1760 Holder.emitUnits(this, DwarfAbbrevSectionSym);
1763 // Emit the abbreviation section.
1764 void DwarfDebug::emitAbbreviations() {
1765 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1767 Holder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection());
1770 // Emit the last address of the section and the end of the line matrix.
1771 void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) {
1772 // Define last address of section.
1773 Asm->OutStreamer.AddComment("Extended Op");
1776 Asm->OutStreamer.AddComment("Op size");
1777 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1);
1778 Asm->OutStreamer.AddComment("DW_LNE_set_address");
1779 Asm->EmitInt8(dwarf::DW_LNE_set_address);
1781 Asm->OutStreamer.AddComment("Section end label");
1783 Asm->OutStreamer.EmitSymbolValue(
1784 Asm->GetTempSymbol("section_end", SectionEnd),
1785 Asm->getDataLayout().getPointerSize());
1787 // Mark end of matrix.
1788 Asm->OutStreamer.AddComment("DW_LNE_end_sequence");
1794 // Emit visible names into a hashed accelerator table section.
1795 void DwarfDebug::emitAccelNames() {
1796 AccelNames.FinalizeTable(Asm, "Names");
1797 Asm->OutStreamer.SwitchSection(
1798 Asm->getObjFileLowering().getDwarfAccelNamesSection());
1799 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin");
1800 Asm->OutStreamer.EmitLabel(SectionBegin);
1802 // Emit the full data.
1803 AccelNames.Emit(Asm, SectionBegin, &InfoHolder);
1806 // Emit objective C classes and categories into a hashed accelerator table
1808 void DwarfDebug::emitAccelObjC() {
1809 AccelObjC.FinalizeTable(Asm, "ObjC");
1810 Asm->OutStreamer.SwitchSection(
1811 Asm->getObjFileLowering().getDwarfAccelObjCSection());
1812 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin");
1813 Asm->OutStreamer.EmitLabel(SectionBegin);
1815 // Emit the full data.
1816 AccelObjC.Emit(Asm, SectionBegin, &InfoHolder);
1819 // Emit namespace dies into a hashed accelerator table.
1820 void DwarfDebug::emitAccelNamespaces() {
1821 AccelNamespace.FinalizeTable(Asm, "namespac");
1822 Asm->OutStreamer.SwitchSection(
1823 Asm->getObjFileLowering().getDwarfAccelNamespaceSection());
1824 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin");
1825 Asm->OutStreamer.EmitLabel(SectionBegin);
1827 // Emit the full data.
1828 AccelNamespace.Emit(Asm, SectionBegin, &InfoHolder);
1831 // Emit type dies into a hashed accelerator table.
1832 void DwarfDebug::emitAccelTypes() {
1834 AccelTypes.FinalizeTable(Asm, "types");
1835 Asm->OutStreamer.SwitchSection(
1836 Asm->getObjFileLowering().getDwarfAccelTypesSection());
1837 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin");
1838 Asm->OutStreamer.EmitLabel(SectionBegin);
1840 // Emit the full data.
1841 AccelTypes.Emit(Asm, SectionBegin, &InfoHolder);
1844 // Public name handling.
1845 // The format for the various pubnames:
1847 // dwarf pubnames - offset/name pairs where the offset is the offset into the CU
1848 // for the DIE that is named.
1850 // gnu pubnames - offset/index value/name tuples where the offset is the offset
1851 // into the CU and the index value is computed according to the type of value
1852 // for the DIE that is named.
1854 // For type units the offset is the offset of the skeleton DIE. For split dwarf
1855 // it's the offset within the debug_info/debug_types dwo section, however, the
1856 // reference in the pubname header doesn't change.
1858 /// computeIndexValue - Compute the gdb index value for the DIE and CU.
1859 static dwarf::PubIndexEntryDescriptor computeIndexValue(DwarfUnit *CU,
1861 dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC;
1863 // We could have a specification DIE that has our most of our knowledge,
1864 // look for that now.
1865 DIEValue *SpecVal = Die->findAttribute(dwarf::DW_AT_specification);
1867 DIE &SpecDIE = cast<DIEEntry>(SpecVal)->getEntry();
1868 if (SpecDIE.findAttribute(dwarf::DW_AT_external))
1869 Linkage = dwarf::GIEL_EXTERNAL;
1870 } else if (Die->findAttribute(dwarf::DW_AT_external))
1871 Linkage = dwarf::GIEL_EXTERNAL;
1873 switch (Die->getTag()) {
1874 case dwarf::DW_TAG_class_type:
1875 case dwarf::DW_TAG_structure_type:
1876 case dwarf::DW_TAG_union_type:
1877 case dwarf::DW_TAG_enumeration_type:
1878 return dwarf::PubIndexEntryDescriptor(
1879 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus
1880 ? dwarf::GIEL_STATIC
1881 : dwarf::GIEL_EXTERNAL);
1882 case dwarf::DW_TAG_typedef:
1883 case dwarf::DW_TAG_base_type:
1884 case dwarf::DW_TAG_subrange_type:
1885 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC);
1886 case dwarf::DW_TAG_namespace:
1887 return dwarf::GIEK_TYPE;
1888 case dwarf::DW_TAG_subprogram:
1889 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage);
1890 case dwarf::DW_TAG_constant:
1891 case dwarf::DW_TAG_variable:
1892 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage);
1893 case dwarf::DW_TAG_enumerator:
1894 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE,
1895 dwarf::GIEL_STATIC);
1897 return dwarf::GIEK_NONE;
1901 /// emitDebugPubNames - Emit visible names into a debug pubnames section.
1903 void DwarfDebug::emitDebugPubNames(bool GnuStyle) {
1904 const MCSection *PSec =
1905 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection()
1906 : Asm->getObjFileLowering().getDwarfPubNamesSection();
1908 emitDebugPubSection(GnuStyle, PSec, "Names", &DwarfUnit::getGlobalNames);
1911 void DwarfDebug::emitDebugPubSection(
1912 bool GnuStyle, const MCSection *PSec, StringRef Name,
1913 const StringMap<const DIE *> &(DwarfUnit::*Accessor)() const) {
1914 for (const auto &NU : CUMap) {
1915 DwarfCompileUnit *TheU = NU.second;
1917 const auto &Globals = (TheU->*Accessor)();
1919 if (Globals.empty())
1922 if (auto Skeleton = static_cast<DwarfCompileUnit *>(TheU->getSkeleton()))
1924 unsigned ID = TheU->getUniqueID();
1926 // Start the dwarf pubnames section.
1927 Asm->OutStreamer.SwitchSection(PSec);
1930 Asm->OutStreamer.AddComment("Length of Public " + Name + " Info");
1931 MCSymbol *BeginLabel = Asm->GetTempSymbol("pub" + Name + "_begin", ID);
1932 MCSymbol *EndLabel = Asm->GetTempSymbol("pub" + Name + "_end", ID);
1933 Asm->EmitLabelDifference(EndLabel, BeginLabel, 4);
1935 Asm->OutStreamer.EmitLabel(BeginLabel);
1937 Asm->OutStreamer.AddComment("DWARF Version");
1938 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION);
1940 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info");
1941 Asm->EmitSectionOffset(TheU->getLabelBegin(), TheU->getSectionSym());
1943 Asm->OutStreamer.AddComment("Compilation Unit Length");
1944 Asm->EmitLabelDifference(TheU->getLabelEnd(), TheU->getLabelBegin(), 4);
1946 // Emit the pubnames for this compilation unit.
1947 for (const auto &GI : Globals) {
1948 const char *Name = GI.getKeyData();
1949 const DIE *Entity = GI.second;
1951 Asm->OutStreamer.AddComment("DIE offset");
1952 Asm->EmitInt32(Entity->getOffset());
1955 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheU, Entity);
1956 Asm->OutStreamer.AddComment(
1957 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " +
1958 dwarf::GDBIndexEntryLinkageString(Desc.Linkage));
1959 Asm->EmitInt8(Desc.toBits());
1962 Asm->OutStreamer.AddComment("External Name");
1963 Asm->OutStreamer.EmitBytes(StringRef(Name, GI.getKeyLength() + 1));
1966 Asm->OutStreamer.AddComment("End Mark");
1968 Asm->OutStreamer.EmitLabel(EndLabel);
1972 void DwarfDebug::emitDebugPubTypes(bool GnuStyle) {
1973 const MCSection *PSec =
1974 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection()
1975 : Asm->getObjFileLowering().getDwarfPubTypesSection();
1977 emitDebugPubSection(GnuStyle, PSec, "Types", &DwarfUnit::getGlobalTypes);
1980 // Emit visible names into a debug str section.
1981 void DwarfDebug::emitDebugStr() {
1982 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1983 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection());
1986 void DwarfDebug::emitDebugLocEntry(ByteStreamer &Streamer,
1987 const DebugLocEntry &Entry) {
1988 assert(Entry.getValues().size() == 1 &&
1989 "multi-value entries are not supported yet.");
1990 const DebugLocEntry::Value Value = Entry.getValues()[0];
1991 DIVariable DV(Value.getVariable());
1992 if (Value.isInt()) {
1993 DIBasicType BTy(resolve(DV.getType()));
1994 if (BTy.Verify() && (BTy.getEncoding() == dwarf::DW_ATE_signed ||
1995 BTy.getEncoding() == dwarf::DW_ATE_signed_char)) {
1996 Streamer.EmitInt8(dwarf::DW_OP_consts, "DW_OP_consts");
1997 Streamer.EmitSLEB128(Value.getInt());
1999 Streamer.EmitInt8(dwarf::DW_OP_constu, "DW_OP_constu");
2000 Streamer.EmitULEB128(Value.getInt());
2002 } else if (Value.isLocation()) {
2003 MachineLocation Loc = Value.getLoc();
2004 if (!DV.hasComplexAddress())
2006 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2008 // Complex address entry.
2009 unsigned N = DV.getNumAddrElements();
2011 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) {
2012 if (Loc.getOffset()) {
2014 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2015 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
2016 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
2017 Streamer.EmitSLEB128(DV.getAddrElement(1));
2019 // If first address element is OpPlus then emit
2020 // DW_OP_breg + Offset instead of DW_OP_reg + Offset.
2021 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1));
2022 Asm->EmitDwarfRegOp(Streamer, TLoc, DV.isIndirect());
2026 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2029 // Emit remaining complex address elements.
2030 for (; i < N; ++i) {
2031 uint64_t Element = DV.getAddrElement(i);
2032 if (Element == DIBuilder::OpPlus) {
2033 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
2034 Streamer.EmitULEB128(DV.getAddrElement(++i));
2035 } else if (Element == DIBuilder::OpDeref) {
2037 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
2039 llvm_unreachable("unknown Opcode found in complex address");
2043 // else ... ignore constant fp. There is not any good way to
2044 // to represent them here in dwarf.
2048 void DwarfDebug::emitDebugLocEntryLocation(const DebugLocEntry &Entry) {
2049 Asm->OutStreamer.AddComment("Loc expr size");
2050 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol();
2051 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol();
2052 Asm->EmitLabelDifference(end, begin, 2);
2053 Asm->OutStreamer.EmitLabel(begin);
2055 APByteStreamer Streamer(*Asm);
2056 emitDebugLocEntry(Streamer, Entry);
2058 Asm->OutStreamer.EmitLabel(end);
2061 // Emit locations into the debug loc section.
2062 void DwarfDebug::emitDebugLoc() {
2063 // Start the dwarf loc section.
2064 Asm->OutStreamer.SwitchSection(
2065 Asm->getObjFileLowering().getDwarfLocSection());
2066 unsigned char Size = Asm->getDataLayout().getPointerSize();
2067 for (const auto &DebugLoc : DotDebugLocEntries) {
2068 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2069 for (const auto &Entry : DebugLoc.List) {
2070 // Set up the range. This range is relative to the entry point of the
2071 // compile unit. This is a hard coded 0 for low_pc when we're emitting
2072 // ranges, or the DW_AT_low_pc on the compile unit otherwise.
2073 const DwarfCompileUnit *CU = Entry.getCU();
2074 if (CU->getRanges().size() == 1) {
2075 // Grab the begin symbol from the first range as our base.
2076 const MCSymbol *Base = CU->getRanges()[0].getStart();
2077 Asm->EmitLabelDifference(Entry.getBeginSym(), Base, Size);
2078 Asm->EmitLabelDifference(Entry.getEndSym(), Base, Size);
2080 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size);
2081 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size);
2084 emitDebugLocEntryLocation(Entry);
2086 Asm->OutStreamer.EmitIntValue(0, Size);
2087 Asm->OutStreamer.EmitIntValue(0, Size);
2091 void DwarfDebug::emitDebugLocDWO() {
2092 Asm->OutStreamer.SwitchSection(
2093 Asm->getObjFileLowering().getDwarfLocDWOSection());
2094 for (const auto &DebugLoc : DotDebugLocEntries) {
2095 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2096 for (const auto &Entry : DebugLoc.List) {
2097 // Just always use start_length for now - at least that's one address
2098 // rather than two. We could get fancier and try to, say, reuse an
2099 // address we know we've emitted elsewhere (the start of the function?
2100 // The start of the CU or CU subrange that encloses this range?)
2101 Asm->EmitInt8(dwarf::DW_LLE_start_length_entry);
2102 unsigned idx = AddrPool.getIndex(Entry.getBeginSym());
2103 Asm->EmitULEB128(idx);
2104 Asm->EmitLabelDifference(Entry.getEndSym(), Entry.getBeginSym(), 4);
2106 emitDebugLocEntryLocation(Entry);
2108 Asm->EmitInt8(dwarf::DW_LLE_end_of_list_entry);
2113 const MCSymbol *Start, *End;
2116 // Emit a debug aranges section, containing a CU lookup for any
2117 // address we can tie back to a CU.
2118 void DwarfDebug::emitDebugARanges() {
2119 // Start the dwarf aranges section.
2120 Asm->OutStreamer.SwitchSection(
2121 Asm->getObjFileLowering().getDwarfARangesSection());
2123 typedef DenseMap<DwarfCompileUnit *, std::vector<ArangeSpan>> SpansType;
2127 // Build a list of sections used.
2128 std::vector<const MCSection *> Sections;
2129 for (const auto &it : SectionMap) {
2130 const MCSection *Section = it.first;
2131 Sections.push_back(Section);
2134 // Sort the sections into order.
2135 // This is only done to ensure consistent output order across different runs.
2136 std::sort(Sections.begin(), Sections.end(), SectionSort);
2138 // Build a set of address spans, sorted by CU.
2139 for (const MCSection *Section : Sections) {
2140 SmallVector<SymbolCU, 8> &List = SectionMap[Section];
2141 if (List.size() < 2)
2144 // Sort the symbols by offset within the section.
2145 std::sort(List.begin(), List.end(),
2146 [&](const SymbolCU &A, const SymbolCU &B) {
2147 unsigned IA = A.Sym ? Asm->OutStreamer.GetSymbolOrder(A.Sym) : 0;
2148 unsigned IB = B.Sym ? Asm->OutStreamer.GetSymbolOrder(B.Sym) : 0;
2150 // Symbols with no order assigned should be placed at the end.
2151 // (e.g. section end labels)
2159 // If we have no section (e.g. common), just write out
2160 // individual spans for each symbol.
2162 for (const SymbolCU &Cur : List) {
2164 Span.Start = Cur.Sym;
2167 Spans[Cur.CU].push_back(Span);
2170 // Build spans between each label.
2171 const MCSymbol *StartSym = List[0].Sym;
2172 for (size_t n = 1, e = List.size(); n < e; n++) {
2173 const SymbolCU &Prev = List[n - 1];
2174 const SymbolCU &Cur = List[n];
2176 // Try and build the longest span we can within the same CU.
2177 if (Cur.CU != Prev.CU) {
2179 Span.Start = StartSym;
2181 Spans[Prev.CU].push_back(Span);
2188 unsigned PtrSize = Asm->getDataLayout().getPointerSize();
2190 // Build a list of CUs used.
2191 std::vector<DwarfCompileUnit *> CUs;
2192 for (const auto &it : Spans) {
2193 DwarfCompileUnit *CU = it.first;
2197 // Sort the CU list (again, to ensure consistent output order).
2198 std::sort(CUs.begin(), CUs.end(), [](const DwarfUnit *A, const DwarfUnit *B) {
2199 return A->getUniqueID() < B->getUniqueID();
2202 // Emit an arange table for each CU we used.
2203 for (DwarfCompileUnit *CU : CUs) {
2204 std::vector<ArangeSpan> &List = Spans[CU];
2206 // Emit size of content not including length itself.
2207 unsigned ContentSize =
2208 sizeof(int16_t) + // DWARF ARange version number
2209 sizeof(int32_t) + // Offset of CU in the .debug_info section
2210 sizeof(int8_t) + // Pointer Size (in bytes)
2211 sizeof(int8_t); // Segment Size (in bytes)
2213 unsigned TupleSize = PtrSize * 2;
2215 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple.
2217 OffsetToAlignment(sizeof(int32_t) + ContentSize, TupleSize);
2219 ContentSize += Padding;
2220 ContentSize += (List.size() + 1) * TupleSize;
2222 // For each compile unit, write the list of spans it covers.
2223 Asm->OutStreamer.AddComment("Length of ARange Set");
2224 Asm->EmitInt32(ContentSize);
2225 Asm->OutStreamer.AddComment("DWARF Arange version number");
2226 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION);
2227 Asm->OutStreamer.AddComment("Offset Into Debug Info Section");
2228 Asm->EmitSectionOffset(CU->getLocalLabelBegin(), CU->getLocalSectionSym());
2229 Asm->OutStreamer.AddComment("Address Size (in bytes)");
2230 Asm->EmitInt8(PtrSize);
2231 Asm->OutStreamer.AddComment("Segment Size (in bytes)");
2234 Asm->OutStreamer.EmitFill(Padding, 0xff);
2236 for (const ArangeSpan &Span : List) {
2237 Asm->EmitLabelReference(Span.Start, PtrSize);
2239 // Calculate the size as being from the span start to it's end.
2241 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize);
2243 // For symbols without an end marker (e.g. common), we
2244 // write a single arange entry containing just that one symbol.
2245 uint64_t Size = SymSize[Span.Start];
2249 Asm->OutStreamer.EmitIntValue(Size, PtrSize);
2253 Asm->OutStreamer.AddComment("ARange terminator");
2254 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2255 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2259 // Emit visible names into a debug ranges section.
2260 void DwarfDebug::emitDebugRanges() {
2261 // Start the dwarf ranges section.
2262 Asm->OutStreamer.SwitchSection(
2263 Asm->getObjFileLowering().getDwarfRangesSection());
2265 // Size for our labels.
2266 unsigned char Size = Asm->getDataLayout().getPointerSize();
2268 // Grab the specific ranges for the compile units in the module.
2269 for (const auto &I : CUMap) {
2270 DwarfCompileUnit *TheCU = I.second;
2272 // Iterate over the misc ranges for the compile units in the module.
2273 for (const RangeSpanList &List : TheCU->getRangeLists()) {
2274 // Emit our symbol so we can find the beginning of the range.
2275 Asm->OutStreamer.EmitLabel(List.getSym());
2277 for (const RangeSpan &Range : List.getRanges()) {
2278 const MCSymbol *Begin = Range.getStart();
2279 const MCSymbol *End = Range.getEnd();
2280 assert(Begin && "Range without a begin symbol?");
2281 assert(End && "Range without an end symbol?");
2282 if (TheCU->getRanges().size() == 1) {
2283 // Grab the begin symbol from the first range as our base.
2284 const MCSymbol *Base = TheCU->getRanges()[0].getStart();
2285 Asm->EmitLabelDifference(Begin, Base, Size);
2286 Asm->EmitLabelDifference(End, Base, Size);
2288 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2289 Asm->OutStreamer.EmitSymbolValue(End, Size);
2293 // And terminate the list with two 0 values.
2294 Asm->OutStreamer.EmitIntValue(0, Size);
2295 Asm->OutStreamer.EmitIntValue(0, Size);
2298 // Now emit a range for the CU itself.
2299 if (TheCU->getRanges().size() > 1) {
2300 Asm->OutStreamer.EmitLabel(
2301 Asm->GetTempSymbol("cu_ranges", TheCU->getUniqueID()));
2302 for (const RangeSpan &Range : TheCU->getRanges()) {
2303 const MCSymbol *Begin = Range.getStart();
2304 const MCSymbol *End = Range.getEnd();
2305 assert(Begin && "Range without a begin symbol?");
2306 assert(End && "Range without an end symbol?");
2307 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2308 Asm->OutStreamer.EmitSymbolValue(End, Size);
2310 // And terminate the list with two 0 values.
2311 Asm->OutStreamer.EmitIntValue(0, Size);
2312 Asm->OutStreamer.EmitIntValue(0, Size);
2317 // DWARF5 Experimental Separate Dwarf emitters.
2319 void DwarfDebug::initSkeletonUnit(const DwarfUnit &U, DIE &Die,
2320 std::unique_ptr<DwarfUnit> NewU) {
2321 NewU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name,
2322 U.getCUNode().getSplitDebugFilename());
2324 if (!CompilationDir.empty())
2325 NewU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
2327 addGnuPubAttributes(*NewU, Die);
2329 SkeletonHolder.addUnit(std::move(NewU));
2332 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list,
2333 // DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id,
2334 // DW_AT_addr_base, DW_AT_ranges_base.
2335 DwarfCompileUnit &DwarfDebug::constructSkeletonCU(const DwarfCompileUnit &CU) {
2337 auto OwnedUnit = make_unique<DwarfCompileUnit>(
2338 CU.getUniqueID(), CU.getCUNode(), Asm, this, &SkeletonHolder);
2339 DwarfCompileUnit &NewCU = *OwnedUnit;
2340 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
2341 DwarfInfoSectionSym);
2343 NewCU.initStmtList(DwarfLineSectionSym);
2345 initSkeletonUnit(CU, NewCU.getUnitDie(), std::move(OwnedUnit));
2350 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_dwo_name,
2352 DwarfTypeUnit &DwarfDebug::constructSkeletonTU(DwarfTypeUnit &TU) {
2353 DwarfCompileUnit &CU = static_cast<DwarfCompileUnit &>(
2354 *SkeletonHolder.getUnits()[TU.getCU().getUniqueID()]);
2356 auto OwnedUnit = make_unique<DwarfTypeUnit>(TU.getUniqueID(), CU, Asm, this,
2358 DwarfTypeUnit &NewTU = *OwnedUnit;
2359 NewTU.setTypeSignature(TU.getTypeSignature());
2360 NewTU.setType(nullptr);
2362 Asm->getObjFileLowering().getDwarfTypesSection(TU.getTypeSignature()));
2364 initSkeletonUnit(TU, NewTU.getUnitDie(), std::move(OwnedUnit));
2368 // Emit the .debug_info.dwo section for separated dwarf. This contains the
2369 // compile units that would normally be in debug_info.
2370 void DwarfDebug::emitDebugInfoDWO() {
2371 assert(useSplitDwarf() && "No split dwarf debug info?");
2372 // Don't pass an abbrev symbol, using a constant zero instead so as not to
2373 // emit relocations into the dwo file.
2374 InfoHolder.emitUnits(this, /* AbbrevSymbol */ nullptr);
2377 // Emit the .debug_abbrev.dwo section for separated dwarf. This contains the
2378 // abbreviations for the .debug_info.dwo section.
2379 void DwarfDebug::emitDebugAbbrevDWO() {
2380 assert(useSplitDwarf() && "No split dwarf?");
2381 InfoHolder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection());
2384 void DwarfDebug::emitDebugLineDWO() {
2385 assert(useSplitDwarf() && "No split dwarf?");
2386 Asm->OutStreamer.SwitchSection(
2387 Asm->getObjFileLowering().getDwarfLineDWOSection());
2388 SplitTypeUnitFileTable.Emit(Asm->OutStreamer);
2391 // Emit the .debug_str.dwo section for separated dwarf. This contains the
2392 // string section and is identical in format to traditional .debug_str
2394 void DwarfDebug::emitDebugStrDWO() {
2395 assert(useSplitDwarf() && "No split dwarf?");
2396 const MCSection *OffSec =
2397 Asm->getObjFileLowering().getDwarfStrOffDWOSection();
2398 const MCSymbol *StrSym = DwarfStrSectionSym;
2399 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(),
2403 MCDwarfDwoLineTable *DwarfDebug::getDwoLineTable(const DwarfCompileUnit &CU) {
2404 if (!useSplitDwarf())
2407 SplitTypeUnitFileTable.setCompilationDir(CU.getCUNode().getDirectory());
2408 return &SplitTypeUnitFileTable;
2411 static uint64_t makeTypeSignature(StringRef Identifier) {
2413 Hash.update(Identifier);
2414 // ... take the least significant 8 bytes and return those. Our MD5
2415 // implementation always returns its results in little endian, swap bytes
2417 MD5::MD5Result Result;
2419 return *reinterpret_cast<support::ulittle64_t *>(Result + 8);
2422 void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU,
2423 StringRef Identifier, DIE &RefDie,
2424 DICompositeType CTy) {
2425 // Fast path if we're building some type units and one has already used the
2426 // address pool we know we're going to throw away all this work anyway, so
2427 // don't bother building dependent types.
2428 if (!TypeUnitsUnderConstruction.empty() && AddrPool.hasBeenUsed())
2431 const DwarfTypeUnit *&TU = DwarfTypeUnits[CTy];
2433 CU.addDIETypeSignature(RefDie, *TU);
2437 bool TopLevelType = TypeUnitsUnderConstruction.empty();
2438 AddrPool.resetUsedFlag();
2441 make_unique<DwarfTypeUnit>(InfoHolder.getUnits().size(), CU, Asm, this,
2442 &InfoHolder, getDwoLineTable(CU));
2443 DwarfTypeUnit &NewTU = *OwnedUnit;
2444 DIE &UnitDie = NewTU.getUnitDie();
2446 TypeUnitsUnderConstruction.push_back(
2447 std::make_pair(std::move(OwnedUnit), CTy));
2449 NewTU.addUInt(UnitDie, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
2452 uint64_t Signature = makeTypeSignature(Identifier);
2453 NewTU.setTypeSignature(Signature);
2455 if (!useSplitDwarf())
2456 CU.applyStmtList(UnitDie);
2460 ? Asm->getObjFileLowering().getDwarfTypesDWOSection(Signature)
2461 : Asm->getObjFileLowering().getDwarfTypesSection(Signature));
2463 NewTU.setType(NewTU.createTypeDIE(CTy));
2466 auto TypeUnitsToAdd = std::move(TypeUnitsUnderConstruction);
2467 TypeUnitsUnderConstruction.clear();
2469 // Types referencing entries in the address table cannot be placed in type
2471 if (AddrPool.hasBeenUsed()) {
2473 // Remove all the types built while building this type.
2474 // This is pessimistic as some of these types might not be dependent on
2475 // the type that used an address.
2476 for (const auto &TU : TypeUnitsToAdd)
2477 DwarfTypeUnits.erase(TU.second);
2479 // Construct this type in the CU directly.
2480 // This is inefficient because all the dependent types will be rebuilt
2481 // from scratch, including building them in type units, discovering that
2482 // they depend on addresses, throwing them out and rebuilding them.
2483 CU.constructTypeDIE(RefDie, CTy);
2487 // If the type wasn't dependent on fission addresses, finish adding the type
2488 // and all its dependent types.
2489 for (auto &TU : TypeUnitsToAdd) {
2490 if (useSplitDwarf())
2491 TU.first->setSkeleton(constructSkeletonTU(*TU.first));
2492 InfoHolder.addUnit(std::move(TU.first));
2495 CU.addDIETypeSignature(RefDie, NewTU);
2498 void DwarfDebug::attachLowHighPC(DwarfCompileUnit &Unit, DIE &D,
2499 MCSymbol *Begin, MCSymbol *End) {
2500 Unit.addLabelAddress(D, dwarf::DW_AT_low_pc, Begin);
2501 if (DwarfVersion < 4)
2502 Unit.addLabelAddress(D, dwarf::DW_AT_high_pc, End);
2504 Unit.addLabelDelta(D, dwarf::DW_AT_high_pc, End, Begin);
2507 // Accelerator table mutators - add each name along with its companion
2508 // DIE to the proper table while ensuring that the name that we're going
2509 // to reference is in the string table. We do this since the names we
2510 // add may not only be identical to the names in the DIE.
2511 void DwarfDebug::addAccelName(StringRef Name, const DIE &Die) {
2512 if (!useDwarfAccelTables())
2514 AccelNames.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2518 void DwarfDebug::addAccelObjC(StringRef Name, const DIE &Die) {
2519 if (!useDwarfAccelTables())
2521 AccelObjC.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2525 void DwarfDebug::addAccelNamespace(StringRef Name, const DIE &Die) {
2526 if (!useDwarfAccelTables())
2528 AccelNamespace.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2532 void DwarfDebug::addAccelType(StringRef Name, const DIE &Die, char Flags) {
2533 if (!useDwarfAccelTables())
2535 AccelTypes.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),