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 (const auto &MI : MBB) {
1445 if (MI.isDebugValue()) {
1446 assert(MI.getNumOperands() > 1 && "Invalid machine instruction!");
1447 // Keep track of user variables in order of appearance. Store the set
1448 // of variables we've already seen as a set of keys in DbgValues.
1449 const MDNode *Var = MI.getDebugVariable();
1450 auto IterPair = DbgValues.insert(
1451 std::make_pair(Var, SmallVector<const MachineInstr *, 4>()));
1452 if (IterPair.second)
1453 UserVariables.push_back(Var);
1454 } else if (!MI.getFlag(MachineInstr::FrameSetup) &&
1455 PrologEndLoc.isUnknown() && !MI.getDebugLoc().isUnknown()) {
1456 // First known non-DBG_VALUE and non-frame setup location marks
1457 // the beginning of the function body.
1458 PrologEndLoc = MI.getDebugLoc();
1463 // Calculate history for local variables.
1464 calculateDbgValueHistory(MF, Asm->TM.getRegisterInfo(), DbgValues);
1466 // Request labels for the full history.
1467 for (auto &I : DbgValues) {
1468 const SmallVectorImpl<const MachineInstr *> &History = I.second;
1469 if (History.empty())
1472 // The first mention of a function argument gets the FunctionBeginSym
1473 // label, so arguments are visible when breaking at function entry.
1474 DIVariable DV(I.first);
1475 if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable &&
1476 getDISubprogram(DV.getContext()).describes(MF->getFunction()))
1477 LabelsBeforeInsn[History.front()] = FunctionBeginSym;
1479 for (const MachineInstr *MI : History) {
1480 if (MI->isDebugValue())
1481 requestLabelBeforeInsn(MI);
1483 requestLabelAfterInsn(MI);
1487 PrevInstLoc = DebugLoc();
1488 PrevLabel = FunctionBeginSym;
1490 // Record beginning of function.
1491 if (!PrologEndLoc.isUnknown()) {
1492 DebugLoc FnStartDL =
1493 PrologEndLoc.getFnDebugLoc(MF->getFunction()->getContext());
1495 FnStartDL.getLine(), FnStartDL.getCol(),
1496 FnStartDL.getScope(MF->getFunction()->getContext()),
1497 // We'd like to list the prologue as "not statements" but GDB behaves
1498 // poorly if we do that. Revisit this with caution/GDB (7.5+) testing.
1499 DWARF2_FLAG_IS_STMT);
1503 void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) {
1504 SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS];
1505 DIVariable DV = Var->getVariable();
1506 // Variables with positive arg numbers are parameters.
1507 if (unsigned ArgNum = DV.getArgNumber()) {
1508 // Keep all parameters in order at the start of the variable list to ensure
1509 // function types are correct (no out-of-order parameters)
1511 // This could be improved by only doing it for optimized builds (unoptimized
1512 // builds have the right order to begin with), searching from the back (this
1513 // would catch the unoptimized case quickly), or doing a binary search
1514 // rather than linear search.
1515 SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin();
1516 while (I != Vars.end()) {
1517 unsigned CurNum = (*I)->getVariable().getArgNumber();
1518 // A local (non-parameter) variable has been found, insert immediately
1522 // A later indexed parameter has been found, insert immediately before it.
1523 if (CurNum > ArgNum)
1527 Vars.insert(I, Var);
1531 Vars.push_back(Var);
1534 // Gather and emit post-function debug information.
1535 void DwarfDebug::endFunction(const MachineFunction *MF) {
1536 // Every beginFunction(MF) call should be followed by an endFunction(MF) call,
1537 // though the beginFunction may not be called at all.
1538 // We should handle both cases.
1542 assert(CurFn == MF);
1543 assert(CurFn != nullptr);
1545 if (!MMI->hasDebugInfo() || LScopes.empty()) {
1546 // If we don't have a lexical scope for this function then there will
1547 // be a hole in the range information. Keep note of this by setting the
1548 // previously used section to nullptr.
1549 PrevSection = nullptr;
1555 // Define end label for subprogram.
1556 FunctionEndSym = Asm->GetTempSymbol("func_end", Asm->getFunctionNumber());
1557 // Assumes in correct section after the entry point.
1558 Asm->OutStreamer.EmitLabel(FunctionEndSym);
1560 // Set DwarfDwarfCompileUnitID in MCContext to default value.
1561 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1563 SmallPtrSet<const MDNode *, 16> ProcessedVars;
1564 collectVariableInfo(ProcessedVars);
1566 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1567 DwarfCompileUnit &TheCU = *SPMap.lookup(FnScope->getScopeNode());
1569 // Construct abstract scopes.
1570 for (LexicalScope *AScope : LScopes.getAbstractScopesList()) {
1571 DISubprogram SP(AScope->getScopeNode());
1572 if (SP.isSubprogram()) {
1573 // Collect info for variables that were optimized out.
1574 DIArray Variables = SP.getVariables();
1575 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1576 DIVariable DV(Variables.getElement(i));
1577 if (!DV || !DV.isVariable() || !ProcessedVars.insert(DV))
1579 // Check that DbgVariable for DV wasn't created earlier, when
1580 // findAbstractVariable() was called for inlined instance of DV.
1581 LLVMContext &Ctx = DV->getContext();
1582 DIVariable CleanDV = cleanseInlinedVariable(DV, Ctx);
1583 if (AbstractVariables.lookup(CleanDV))
1585 if (LexicalScope *Scope = LScopes.findAbstractScope(DV.getContext()))
1586 addScopeVariable(Scope, new DbgVariable(DV, nullptr, this));
1589 if (ProcessedSPNodes.count(AScope->getScopeNode()) == 0)
1590 constructAbstractSubprogramScopeDIE(TheCU, AScope);
1593 DIE &CurFnDIE = constructSubprogramScopeDIE(TheCU, FnScope);
1594 if (!CurFn->getTarget().Options.DisableFramePointerElim(*CurFn))
1595 TheCU.addFlag(CurFnDIE, dwarf::DW_AT_APPLE_omit_frame_ptr);
1597 // Add the range of this function to the list of ranges for the CU.
1598 RangeSpan Span(FunctionBeginSym, FunctionEndSym);
1599 TheCU.addRange(std::move(Span));
1600 PrevSection = Asm->getCurrentSection();
1604 for (auto &I : ScopeVariables)
1605 DeleteContainerPointers(I.second);
1606 ScopeVariables.clear();
1607 DeleteContainerPointers(CurrentFnArguments);
1608 UserVariables.clear();
1610 AbstractVariables.clear();
1611 LabelsBeforeInsn.clear();
1612 LabelsAfterInsn.clear();
1613 PrevLabel = nullptr;
1617 // Register a source line with debug info. Returns the unique label that was
1618 // emitted and which provides correspondence to the source line list.
1619 void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S,
1624 unsigned Discriminator = 0;
1626 DIDescriptor Scope(S);
1628 if (Scope.isCompileUnit()) {
1629 DICompileUnit CU(S);
1630 Fn = CU.getFilename();
1631 Dir = CU.getDirectory();
1632 } else if (Scope.isFile()) {
1634 Fn = F.getFilename();
1635 Dir = F.getDirectory();
1636 } else if (Scope.isSubprogram()) {
1638 Fn = SP.getFilename();
1639 Dir = SP.getDirectory();
1640 } else if (Scope.isLexicalBlockFile()) {
1641 DILexicalBlockFile DBF(S);
1642 Fn = DBF.getFilename();
1643 Dir = DBF.getDirectory();
1644 } else if (Scope.isLexicalBlock()) {
1645 DILexicalBlock DB(S);
1646 Fn = DB.getFilename();
1647 Dir = DB.getDirectory();
1648 Discriminator = DB.getDiscriminator();
1650 llvm_unreachable("Unexpected scope info");
1652 unsigned CUID = Asm->OutStreamer.getContext().getDwarfCompileUnitID();
1653 Src = static_cast<DwarfCompileUnit &>(*InfoHolder.getUnits()[CUID])
1654 .getOrCreateSourceID(Fn, Dir);
1656 Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0,
1660 //===----------------------------------------------------------------------===//
1662 //===----------------------------------------------------------------------===//
1664 // Emit initial Dwarf sections with a label at the start of each one.
1665 void DwarfDebug::emitSectionLabels() {
1666 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
1668 // Dwarf sections base addresses.
1669 DwarfInfoSectionSym =
1670 emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info");
1671 if (useSplitDwarf())
1672 DwarfInfoDWOSectionSym =
1673 emitSectionSym(Asm, TLOF.getDwarfInfoDWOSection(), "section_info_dwo");
1674 DwarfAbbrevSectionSym =
1675 emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev");
1676 if (useSplitDwarf())
1677 DwarfAbbrevDWOSectionSym = emitSectionSym(
1678 Asm, TLOF.getDwarfAbbrevDWOSection(), "section_abbrev_dwo");
1679 if (GenerateARangeSection)
1680 emitSectionSym(Asm, TLOF.getDwarfARangesSection());
1682 DwarfLineSectionSym =
1683 emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line");
1684 if (GenerateGnuPubSections) {
1685 DwarfGnuPubNamesSectionSym =
1686 emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection());
1687 DwarfGnuPubTypesSectionSym =
1688 emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection());
1689 } else if (HasDwarfPubSections) {
1690 emitSectionSym(Asm, TLOF.getDwarfPubNamesSection());
1691 emitSectionSym(Asm, TLOF.getDwarfPubTypesSection());
1694 DwarfStrSectionSym =
1695 emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string");
1696 if (useSplitDwarf()) {
1697 DwarfStrDWOSectionSym =
1698 emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string");
1699 DwarfAddrSectionSym =
1700 emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec");
1701 DwarfDebugLocSectionSym =
1702 emitSectionSym(Asm, TLOF.getDwarfLocDWOSection(), "skel_loc");
1704 DwarfDebugLocSectionSym =
1705 emitSectionSym(Asm, TLOF.getDwarfLocSection(), "section_debug_loc");
1706 DwarfDebugRangeSectionSym =
1707 emitSectionSym(Asm, TLOF.getDwarfRangesSection(), "debug_range");
1710 // Recursively emits a debug information entry.
1711 void DwarfDebug::emitDIE(DIE &Die) {
1712 // Get the abbreviation for this DIE.
1713 const DIEAbbrev &Abbrev = Die.getAbbrev();
1715 // Emit the code (index) for the abbreviation.
1716 if (Asm->isVerbose())
1717 Asm->OutStreamer.AddComment("Abbrev [" + Twine(Abbrev.getNumber()) +
1718 "] 0x" + Twine::utohexstr(Die.getOffset()) +
1719 ":0x" + Twine::utohexstr(Die.getSize()) + " " +
1720 dwarf::TagString(Abbrev.getTag()));
1721 Asm->EmitULEB128(Abbrev.getNumber());
1723 const SmallVectorImpl<DIEValue *> &Values = Die.getValues();
1724 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
1726 // Emit the DIE attribute values.
1727 for (unsigned i = 0, N = Values.size(); i < N; ++i) {
1728 dwarf::Attribute Attr = AbbrevData[i].getAttribute();
1729 dwarf::Form Form = AbbrevData[i].getForm();
1730 assert(Form && "Too many attributes for DIE (check abbreviation)");
1732 if (Asm->isVerbose()) {
1733 Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr));
1734 if (Attr == dwarf::DW_AT_accessibility)
1735 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(
1736 cast<DIEInteger>(Values[i])->getValue()));
1739 // Emit an attribute using the defined form.
1740 Values[i]->EmitValue(Asm, Form);
1743 // Emit the DIE children if any.
1744 if (Abbrev.hasChildren()) {
1745 for (auto &Child : Die.getChildren())
1748 Asm->OutStreamer.AddComment("End Of Children Mark");
1753 // Emit the debug info section.
1754 void DwarfDebug::emitDebugInfo() {
1755 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1757 Holder.emitUnits(this, DwarfAbbrevSectionSym);
1760 // Emit the abbreviation section.
1761 void DwarfDebug::emitAbbreviations() {
1762 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1764 Holder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection());
1767 // Emit the last address of the section and the end of the line matrix.
1768 void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) {
1769 // Define last address of section.
1770 Asm->OutStreamer.AddComment("Extended Op");
1773 Asm->OutStreamer.AddComment("Op size");
1774 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1);
1775 Asm->OutStreamer.AddComment("DW_LNE_set_address");
1776 Asm->EmitInt8(dwarf::DW_LNE_set_address);
1778 Asm->OutStreamer.AddComment("Section end label");
1780 Asm->OutStreamer.EmitSymbolValue(
1781 Asm->GetTempSymbol("section_end", SectionEnd),
1782 Asm->getDataLayout().getPointerSize());
1784 // Mark end of matrix.
1785 Asm->OutStreamer.AddComment("DW_LNE_end_sequence");
1791 // Emit visible names into a hashed accelerator table section.
1792 void DwarfDebug::emitAccelNames() {
1793 AccelNames.FinalizeTable(Asm, "Names");
1794 Asm->OutStreamer.SwitchSection(
1795 Asm->getObjFileLowering().getDwarfAccelNamesSection());
1796 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin");
1797 Asm->OutStreamer.EmitLabel(SectionBegin);
1799 // Emit the full data.
1800 AccelNames.Emit(Asm, SectionBegin, &InfoHolder);
1803 // Emit objective C classes and categories into a hashed accelerator table
1805 void DwarfDebug::emitAccelObjC() {
1806 AccelObjC.FinalizeTable(Asm, "ObjC");
1807 Asm->OutStreamer.SwitchSection(
1808 Asm->getObjFileLowering().getDwarfAccelObjCSection());
1809 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin");
1810 Asm->OutStreamer.EmitLabel(SectionBegin);
1812 // Emit the full data.
1813 AccelObjC.Emit(Asm, SectionBegin, &InfoHolder);
1816 // Emit namespace dies into a hashed accelerator table.
1817 void DwarfDebug::emitAccelNamespaces() {
1818 AccelNamespace.FinalizeTable(Asm, "namespac");
1819 Asm->OutStreamer.SwitchSection(
1820 Asm->getObjFileLowering().getDwarfAccelNamespaceSection());
1821 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin");
1822 Asm->OutStreamer.EmitLabel(SectionBegin);
1824 // Emit the full data.
1825 AccelNamespace.Emit(Asm, SectionBegin, &InfoHolder);
1828 // Emit type dies into a hashed accelerator table.
1829 void DwarfDebug::emitAccelTypes() {
1831 AccelTypes.FinalizeTable(Asm, "types");
1832 Asm->OutStreamer.SwitchSection(
1833 Asm->getObjFileLowering().getDwarfAccelTypesSection());
1834 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin");
1835 Asm->OutStreamer.EmitLabel(SectionBegin);
1837 // Emit the full data.
1838 AccelTypes.Emit(Asm, SectionBegin, &InfoHolder);
1841 // Public name handling.
1842 // The format for the various pubnames:
1844 // dwarf pubnames - offset/name pairs where the offset is the offset into the CU
1845 // for the DIE that is named.
1847 // gnu pubnames - offset/index value/name tuples where the offset is the offset
1848 // into the CU and the index value is computed according to the type of value
1849 // for the DIE that is named.
1851 // For type units the offset is the offset of the skeleton DIE. For split dwarf
1852 // it's the offset within the debug_info/debug_types dwo section, however, the
1853 // reference in the pubname header doesn't change.
1855 /// computeIndexValue - Compute the gdb index value for the DIE and CU.
1856 static dwarf::PubIndexEntryDescriptor computeIndexValue(DwarfUnit *CU,
1858 dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC;
1860 // We could have a specification DIE that has our most of our knowledge,
1861 // look for that now.
1862 DIEValue *SpecVal = Die->findAttribute(dwarf::DW_AT_specification);
1864 DIE &SpecDIE = cast<DIEEntry>(SpecVal)->getEntry();
1865 if (SpecDIE.findAttribute(dwarf::DW_AT_external))
1866 Linkage = dwarf::GIEL_EXTERNAL;
1867 } else if (Die->findAttribute(dwarf::DW_AT_external))
1868 Linkage = dwarf::GIEL_EXTERNAL;
1870 switch (Die->getTag()) {
1871 case dwarf::DW_TAG_class_type:
1872 case dwarf::DW_TAG_structure_type:
1873 case dwarf::DW_TAG_union_type:
1874 case dwarf::DW_TAG_enumeration_type:
1875 return dwarf::PubIndexEntryDescriptor(
1876 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus
1877 ? dwarf::GIEL_STATIC
1878 : dwarf::GIEL_EXTERNAL);
1879 case dwarf::DW_TAG_typedef:
1880 case dwarf::DW_TAG_base_type:
1881 case dwarf::DW_TAG_subrange_type:
1882 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC);
1883 case dwarf::DW_TAG_namespace:
1884 return dwarf::GIEK_TYPE;
1885 case dwarf::DW_TAG_subprogram:
1886 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage);
1887 case dwarf::DW_TAG_constant:
1888 case dwarf::DW_TAG_variable:
1889 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage);
1890 case dwarf::DW_TAG_enumerator:
1891 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE,
1892 dwarf::GIEL_STATIC);
1894 return dwarf::GIEK_NONE;
1898 /// emitDebugPubNames - Emit visible names into a debug pubnames section.
1900 void DwarfDebug::emitDebugPubNames(bool GnuStyle) {
1901 const MCSection *PSec =
1902 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection()
1903 : Asm->getObjFileLowering().getDwarfPubNamesSection();
1905 emitDebugPubSection(GnuStyle, PSec, "Names", &DwarfUnit::getGlobalNames);
1908 void DwarfDebug::emitDebugPubSection(
1909 bool GnuStyle, const MCSection *PSec, StringRef Name,
1910 const StringMap<const DIE *> &(DwarfUnit::*Accessor)() const) {
1911 for (const auto &NU : CUMap) {
1912 DwarfCompileUnit *TheU = NU.second;
1914 const auto &Globals = (TheU->*Accessor)();
1916 if (Globals.empty())
1919 if (auto Skeleton = static_cast<DwarfCompileUnit *>(TheU->getSkeleton()))
1921 unsigned ID = TheU->getUniqueID();
1923 // Start the dwarf pubnames section.
1924 Asm->OutStreamer.SwitchSection(PSec);
1927 Asm->OutStreamer.AddComment("Length of Public " + Name + " Info");
1928 MCSymbol *BeginLabel = Asm->GetTempSymbol("pub" + Name + "_begin", ID);
1929 MCSymbol *EndLabel = Asm->GetTempSymbol("pub" + Name + "_end", ID);
1930 Asm->EmitLabelDifference(EndLabel, BeginLabel, 4);
1932 Asm->OutStreamer.EmitLabel(BeginLabel);
1934 Asm->OutStreamer.AddComment("DWARF Version");
1935 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION);
1937 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info");
1938 Asm->EmitSectionOffset(TheU->getLabelBegin(), TheU->getSectionSym());
1940 Asm->OutStreamer.AddComment("Compilation Unit Length");
1941 Asm->EmitLabelDifference(TheU->getLabelEnd(), TheU->getLabelBegin(), 4);
1943 // Emit the pubnames for this compilation unit.
1944 for (const auto &GI : Globals) {
1945 const char *Name = GI.getKeyData();
1946 const DIE *Entity = GI.second;
1948 Asm->OutStreamer.AddComment("DIE offset");
1949 Asm->EmitInt32(Entity->getOffset());
1952 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheU, Entity);
1953 Asm->OutStreamer.AddComment(
1954 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " +
1955 dwarf::GDBIndexEntryLinkageString(Desc.Linkage));
1956 Asm->EmitInt8(Desc.toBits());
1959 Asm->OutStreamer.AddComment("External Name");
1960 Asm->OutStreamer.EmitBytes(StringRef(Name, GI.getKeyLength() + 1));
1963 Asm->OutStreamer.AddComment("End Mark");
1965 Asm->OutStreamer.EmitLabel(EndLabel);
1969 void DwarfDebug::emitDebugPubTypes(bool GnuStyle) {
1970 const MCSection *PSec =
1971 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection()
1972 : Asm->getObjFileLowering().getDwarfPubTypesSection();
1974 emitDebugPubSection(GnuStyle, PSec, "Types", &DwarfUnit::getGlobalTypes);
1977 // Emit visible names into a debug str section.
1978 void DwarfDebug::emitDebugStr() {
1979 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1980 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection());
1983 void DwarfDebug::emitDebugLocEntry(ByteStreamer &Streamer,
1984 const DebugLocEntry &Entry) {
1985 assert(Entry.getValues().size() == 1 &&
1986 "multi-value entries are not supported yet.");
1987 const DebugLocEntry::Value Value = Entry.getValues()[0];
1988 DIVariable DV(Value.getVariable());
1989 if (Value.isInt()) {
1990 DIBasicType BTy(resolve(DV.getType()));
1991 if (BTy.Verify() && (BTy.getEncoding() == dwarf::DW_ATE_signed ||
1992 BTy.getEncoding() == dwarf::DW_ATE_signed_char)) {
1993 Streamer.EmitInt8(dwarf::DW_OP_consts, "DW_OP_consts");
1994 Streamer.EmitSLEB128(Value.getInt());
1996 Streamer.EmitInt8(dwarf::DW_OP_constu, "DW_OP_constu");
1997 Streamer.EmitULEB128(Value.getInt());
1999 } else if (Value.isLocation()) {
2000 MachineLocation Loc = Value.getLoc();
2001 if (!DV.hasComplexAddress())
2003 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2005 // Complex address entry.
2006 unsigned N = DV.getNumAddrElements();
2008 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) {
2009 if (Loc.getOffset()) {
2011 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2012 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
2013 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
2014 Streamer.EmitSLEB128(DV.getAddrElement(1));
2016 // If first address element is OpPlus then emit
2017 // DW_OP_breg + Offset instead of DW_OP_reg + Offset.
2018 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1));
2019 Asm->EmitDwarfRegOp(Streamer, TLoc, DV.isIndirect());
2023 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2026 // Emit remaining complex address elements.
2027 for (; i < N; ++i) {
2028 uint64_t Element = DV.getAddrElement(i);
2029 if (Element == DIBuilder::OpPlus) {
2030 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
2031 Streamer.EmitULEB128(DV.getAddrElement(++i));
2032 } else if (Element == DIBuilder::OpDeref) {
2034 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
2036 llvm_unreachable("unknown Opcode found in complex address");
2040 // else ... ignore constant fp. There is not any good way to
2041 // to represent them here in dwarf.
2045 void DwarfDebug::emitDebugLocEntryLocation(const DebugLocEntry &Entry) {
2046 Asm->OutStreamer.AddComment("Loc expr size");
2047 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol();
2048 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol();
2049 Asm->EmitLabelDifference(end, begin, 2);
2050 Asm->OutStreamer.EmitLabel(begin);
2052 APByteStreamer Streamer(*Asm);
2053 emitDebugLocEntry(Streamer, Entry);
2055 Asm->OutStreamer.EmitLabel(end);
2058 // Emit locations into the debug loc section.
2059 void DwarfDebug::emitDebugLoc() {
2060 // Start the dwarf loc section.
2061 Asm->OutStreamer.SwitchSection(
2062 Asm->getObjFileLowering().getDwarfLocSection());
2063 unsigned char Size = Asm->getDataLayout().getPointerSize();
2064 for (const auto &DebugLoc : DotDebugLocEntries) {
2065 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2066 for (const auto &Entry : DebugLoc.List) {
2067 // Set up the range. This range is relative to the entry point of the
2068 // compile unit. This is a hard coded 0 for low_pc when we're emitting
2069 // ranges, or the DW_AT_low_pc on the compile unit otherwise.
2070 const DwarfCompileUnit *CU = Entry.getCU();
2071 if (CU->getRanges().size() == 1) {
2072 // Grab the begin symbol from the first range as our base.
2073 const MCSymbol *Base = CU->getRanges()[0].getStart();
2074 Asm->EmitLabelDifference(Entry.getBeginSym(), Base, Size);
2075 Asm->EmitLabelDifference(Entry.getEndSym(), Base, Size);
2077 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size);
2078 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size);
2081 emitDebugLocEntryLocation(Entry);
2083 Asm->OutStreamer.EmitIntValue(0, Size);
2084 Asm->OutStreamer.EmitIntValue(0, Size);
2088 void DwarfDebug::emitDebugLocDWO() {
2089 Asm->OutStreamer.SwitchSection(
2090 Asm->getObjFileLowering().getDwarfLocDWOSection());
2091 for (const auto &DebugLoc : DotDebugLocEntries) {
2092 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2093 for (const auto &Entry : DebugLoc.List) {
2094 // Just always use start_length for now - at least that's one address
2095 // rather than two. We could get fancier and try to, say, reuse an
2096 // address we know we've emitted elsewhere (the start of the function?
2097 // The start of the CU or CU subrange that encloses this range?)
2098 Asm->EmitInt8(dwarf::DW_LLE_start_length_entry);
2099 unsigned idx = AddrPool.getIndex(Entry.getBeginSym());
2100 Asm->EmitULEB128(idx);
2101 Asm->EmitLabelDifference(Entry.getEndSym(), Entry.getBeginSym(), 4);
2103 emitDebugLocEntryLocation(Entry);
2105 Asm->EmitInt8(dwarf::DW_LLE_end_of_list_entry);
2110 const MCSymbol *Start, *End;
2113 // Emit a debug aranges section, containing a CU lookup for any
2114 // address we can tie back to a CU.
2115 void DwarfDebug::emitDebugARanges() {
2116 // Start the dwarf aranges section.
2117 Asm->OutStreamer.SwitchSection(
2118 Asm->getObjFileLowering().getDwarfARangesSection());
2120 typedef DenseMap<DwarfCompileUnit *, std::vector<ArangeSpan>> SpansType;
2124 // Build a list of sections used.
2125 std::vector<const MCSection *> Sections;
2126 for (const auto &it : SectionMap) {
2127 const MCSection *Section = it.first;
2128 Sections.push_back(Section);
2131 // Sort the sections into order.
2132 // This is only done to ensure consistent output order across different runs.
2133 std::sort(Sections.begin(), Sections.end(), SectionSort);
2135 // Build a set of address spans, sorted by CU.
2136 for (const MCSection *Section : Sections) {
2137 SmallVector<SymbolCU, 8> &List = SectionMap[Section];
2138 if (List.size() < 2)
2141 // Sort the symbols by offset within the section.
2142 std::sort(List.begin(), List.end(),
2143 [&](const SymbolCU &A, const SymbolCU &B) {
2144 unsigned IA = A.Sym ? Asm->OutStreamer.GetSymbolOrder(A.Sym) : 0;
2145 unsigned IB = B.Sym ? Asm->OutStreamer.GetSymbolOrder(B.Sym) : 0;
2147 // Symbols with no order assigned should be placed at the end.
2148 // (e.g. section end labels)
2156 // If we have no section (e.g. common), just write out
2157 // individual spans for each symbol.
2159 for (const SymbolCU &Cur : List) {
2161 Span.Start = Cur.Sym;
2164 Spans[Cur.CU].push_back(Span);
2167 // Build spans between each label.
2168 const MCSymbol *StartSym = List[0].Sym;
2169 for (size_t n = 1, e = List.size(); n < e; n++) {
2170 const SymbolCU &Prev = List[n - 1];
2171 const SymbolCU &Cur = List[n];
2173 // Try and build the longest span we can within the same CU.
2174 if (Cur.CU != Prev.CU) {
2176 Span.Start = StartSym;
2178 Spans[Prev.CU].push_back(Span);
2185 unsigned PtrSize = Asm->getDataLayout().getPointerSize();
2187 // Build a list of CUs used.
2188 std::vector<DwarfCompileUnit *> CUs;
2189 for (const auto &it : Spans) {
2190 DwarfCompileUnit *CU = it.first;
2194 // Sort the CU list (again, to ensure consistent output order).
2195 std::sort(CUs.begin(), CUs.end(), [](const DwarfUnit *A, const DwarfUnit *B) {
2196 return A->getUniqueID() < B->getUniqueID();
2199 // Emit an arange table for each CU we used.
2200 for (DwarfCompileUnit *CU : CUs) {
2201 std::vector<ArangeSpan> &List = Spans[CU];
2203 // Emit size of content not including length itself.
2204 unsigned ContentSize =
2205 sizeof(int16_t) + // DWARF ARange version number
2206 sizeof(int32_t) + // Offset of CU in the .debug_info section
2207 sizeof(int8_t) + // Pointer Size (in bytes)
2208 sizeof(int8_t); // Segment Size (in bytes)
2210 unsigned TupleSize = PtrSize * 2;
2212 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple.
2214 OffsetToAlignment(sizeof(int32_t) + ContentSize, TupleSize);
2216 ContentSize += Padding;
2217 ContentSize += (List.size() + 1) * TupleSize;
2219 // For each compile unit, write the list of spans it covers.
2220 Asm->OutStreamer.AddComment("Length of ARange Set");
2221 Asm->EmitInt32(ContentSize);
2222 Asm->OutStreamer.AddComment("DWARF Arange version number");
2223 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION);
2224 Asm->OutStreamer.AddComment("Offset Into Debug Info Section");
2225 Asm->EmitSectionOffset(CU->getLocalLabelBegin(), CU->getLocalSectionSym());
2226 Asm->OutStreamer.AddComment("Address Size (in bytes)");
2227 Asm->EmitInt8(PtrSize);
2228 Asm->OutStreamer.AddComment("Segment Size (in bytes)");
2231 Asm->OutStreamer.EmitFill(Padding, 0xff);
2233 for (const ArangeSpan &Span : List) {
2234 Asm->EmitLabelReference(Span.Start, PtrSize);
2236 // Calculate the size as being from the span start to it's end.
2238 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize);
2240 // For symbols without an end marker (e.g. common), we
2241 // write a single arange entry containing just that one symbol.
2242 uint64_t Size = SymSize[Span.Start];
2246 Asm->OutStreamer.EmitIntValue(Size, PtrSize);
2250 Asm->OutStreamer.AddComment("ARange terminator");
2251 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2252 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2256 // Emit visible names into a debug ranges section.
2257 void DwarfDebug::emitDebugRanges() {
2258 // Start the dwarf ranges section.
2259 Asm->OutStreamer.SwitchSection(
2260 Asm->getObjFileLowering().getDwarfRangesSection());
2262 // Size for our labels.
2263 unsigned char Size = Asm->getDataLayout().getPointerSize();
2265 // Grab the specific ranges for the compile units in the module.
2266 for (const auto &I : CUMap) {
2267 DwarfCompileUnit *TheCU = I.second;
2269 // Iterate over the misc ranges for the compile units in the module.
2270 for (const RangeSpanList &List : TheCU->getRangeLists()) {
2271 // Emit our symbol so we can find the beginning of the range.
2272 Asm->OutStreamer.EmitLabel(List.getSym());
2274 for (const RangeSpan &Range : List.getRanges()) {
2275 const MCSymbol *Begin = Range.getStart();
2276 const MCSymbol *End = Range.getEnd();
2277 assert(Begin && "Range without a begin symbol?");
2278 assert(End && "Range without an end symbol?");
2279 if (TheCU->getRanges().size() == 1) {
2280 // Grab the begin symbol from the first range as our base.
2281 const MCSymbol *Base = TheCU->getRanges()[0].getStart();
2282 Asm->EmitLabelDifference(Begin, Base, Size);
2283 Asm->EmitLabelDifference(End, Base, Size);
2285 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2286 Asm->OutStreamer.EmitSymbolValue(End, Size);
2290 // And terminate the list with two 0 values.
2291 Asm->OutStreamer.EmitIntValue(0, Size);
2292 Asm->OutStreamer.EmitIntValue(0, Size);
2295 // Now emit a range for the CU itself.
2296 if (TheCU->getRanges().size() > 1) {
2297 Asm->OutStreamer.EmitLabel(
2298 Asm->GetTempSymbol("cu_ranges", TheCU->getUniqueID()));
2299 for (const RangeSpan &Range : TheCU->getRanges()) {
2300 const MCSymbol *Begin = Range.getStart();
2301 const MCSymbol *End = Range.getEnd();
2302 assert(Begin && "Range without a begin symbol?");
2303 assert(End && "Range without an end symbol?");
2304 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2305 Asm->OutStreamer.EmitSymbolValue(End, Size);
2307 // And terminate the list with two 0 values.
2308 Asm->OutStreamer.EmitIntValue(0, Size);
2309 Asm->OutStreamer.EmitIntValue(0, Size);
2314 // DWARF5 Experimental Separate Dwarf emitters.
2316 void DwarfDebug::initSkeletonUnit(const DwarfUnit &U, DIE &Die,
2317 std::unique_ptr<DwarfUnit> NewU) {
2318 NewU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name,
2319 U.getCUNode().getSplitDebugFilename());
2321 if (!CompilationDir.empty())
2322 NewU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
2324 addGnuPubAttributes(*NewU, Die);
2326 SkeletonHolder.addUnit(std::move(NewU));
2329 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list,
2330 // DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id,
2331 // DW_AT_addr_base, DW_AT_ranges_base.
2332 DwarfCompileUnit &DwarfDebug::constructSkeletonCU(const DwarfCompileUnit &CU) {
2334 auto OwnedUnit = make_unique<DwarfCompileUnit>(
2335 CU.getUniqueID(), CU.getCUNode(), Asm, this, &SkeletonHolder);
2336 DwarfCompileUnit &NewCU = *OwnedUnit;
2337 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
2338 DwarfInfoSectionSym);
2340 NewCU.initStmtList(DwarfLineSectionSym);
2342 initSkeletonUnit(CU, NewCU.getUnitDie(), std::move(OwnedUnit));
2347 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_dwo_name,
2349 DwarfTypeUnit &DwarfDebug::constructSkeletonTU(DwarfTypeUnit &TU) {
2350 DwarfCompileUnit &CU = static_cast<DwarfCompileUnit &>(
2351 *SkeletonHolder.getUnits()[TU.getCU().getUniqueID()]);
2353 auto OwnedUnit = make_unique<DwarfTypeUnit>(TU.getUniqueID(), CU, Asm, this,
2355 DwarfTypeUnit &NewTU = *OwnedUnit;
2356 NewTU.setTypeSignature(TU.getTypeSignature());
2357 NewTU.setType(nullptr);
2359 Asm->getObjFileLowering().getDwarfTypesSection(TU.getTypeSignature()));
2361 initSkeletonUnit(TU, NewTU.getUnitDie(), std::move(OwnedUnit));
2365 // Emit the .debug_info.dwo section for separated dwarf. This contains the
2366 // compile units that would normally be in debug_info.
2367 void DwarfDebug::emitDebugInfoDWO() {
2368 assert(useSplitDwarf() && "No split dwarf debug info?");
2369 // Don't pass an abbrev symbol, using a constant zero instead so as not to
2370 // emit relocations into the dwo file.
2371 InfoHolder.emitUnits(this, /* AbbrevSymbol */ nullptr);
2374 // Emit the .debug_abbrev.dwo section for separated dwarf. This contains the
2375 // abbreviations for the .debug_info.dwo section.
2376 void DwarfDebug::emitDebugAbbrevDWO() {
2377 assert(useSplitDwarf() && "No split dwarf?");
2378 InfoHolder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection());
2381 void DwarfDebug::emitDebugLineDWO() {
2382 assert(useSplitDwarf() && "No split dwarf?");
2383 Asm->OutStreamer.SwitchSection(
2384 Asm->getObjFileLowering().getDwarfLineDWOSection());
2385 SplitTypeUnitFileTable.Emit(Asm->OutStreamer);
2388 // Emit the .debug_str.dwo section for separated dwarf. This contains the
2389 // string section and is identical in format to traditional .debug_str
2391 void DwarfDebug::emitDebugStrDWO() {
2392 assert(useSplitDwarf() && "No split dwarf?");
2393 const MCSection *OffSec =
2394 Asm->getObjFileLowering().getDwarfStrOffDWOSection();
2395 const MCSymbol *StrSym = DwarfStrSectionSym;
2396 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(),
2400 MCDwarfDwoLineTable *DwarfDebug::getDwoLineTable(const DwarfCompileUnit &CU) {
2401 if (!useSplitDwarf())
2404 SplitTypeUnitFileTable.setCompilationDir(CU.getCUNode().getDirectory());
2405 return &SplitTypeUnitFileTable;
2408 static uint64_t makeTypeSignature(StringRef Identifier) {
2410 Hash.update(Identifier);
2411 // ... take the least significant 8 bytes and return those. Our MD5
2412 // implementation always returns its results in little endian, swap bytes
2414 MD5::MD5Result Result;
2416 return *reinterpret_cast<support::ulittle64_t *>(Result + 8);
2419 void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU,
2420 StringRef Identifier, DIE &RefDie,
2421 DICompositeType CTy) {
2422 // Fast path if we're building some type units and one has already used the
2423 // address pool we know we're going to throw away all this work anyway, so
2424 // don't bother building dependent types.
2425 if (!TypeUnitsUnderConstruction.empty() && AddrPool.hasBeenUsed())
2428 const DwarfTypeUnit *&TU = DwarfTypeUnits[CTy];
2430 CU.addDIETypeSignature(RefDie, *TU);
2434 bool TopLevelType = TypeUnitsUnderConstruction.empty();
2435 AddrPool.resetUsedFlag();
2438 make_unique<DwarfTypeUnit>(InfoHolder.getUnits().size(), CU, Asm, this,
2439 &InfoHolder, getDwoLineTable(CU));
2440 DwarfTypeUnit &NewTU = *OwnedUnit;
2441 DIE &UnitDie = NewTU.getUnitDie();
2443 TypeUnitsUnderConstruction.push_back(
2444 std::make_pair(std::move(OwnedUnit), CTy));
2446 NewTU.addUInt(UnitDie, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
2449 uint64_t Signature = makeTypeSignature(Identifier);
2450 NewTU.setTypeSignature(Signature);
2452 if (!useSplitDwarf())
2453 CU.applyStmtList(UnitDie);
2457 ? Asm->getObjFileLowering().getDwarfTypesDWOSection(Signature)
2458 : Asm->getObjFileLowering().getDwarfTypesSection(Signature));
2460 NewTU.setType(NewTU.createTypeDIE(CTy));
2463 auto TypeUnitsToAdd = std::move(TypeUnitsUnderConstruction);
2464 TypeUnitsUnderConstruction.clear();
2466 // Types referencing entries in the address table cannot be placed in type
2468 if (AddrPool.hasBeenUsed()) {
2470 // Remove all the types built while building this type.
2471 // This is pessimistic as some of these types might not be dependent on
2472 // the type that used an address.
2473 for (const auto &TU : TypeUnitsToAdd)
2474 DwarfTypeUnits.erase(TU.second);
2476 // Construct this type in the CU directly.
2477 // This is inefficient because all the dependent types will be rebuilt
2478 // from scratch, including building them in type units, discovering that
2479 // they depend on addresses, throwing them out and rebuilding them.
2480 CU.constructTypeDIE(RefDie, CTy);
2484 // If the type wasn't dependent on fission addresses, finish adding the type
2485 // and all its dependent types.
2486 for (auto &TU : TypeUnitsToAdd) {
2487 if (useSplitDwarf())
2488 TU.first->setSkeleton(constructSkeletonTU(*TU.first));
2489 InfoHolder.addUnit(std::move(TU.first));
2492 CU.addDIETypeSignature(RefDie, NewTU);
2495 void DwarfDebug::attachLowHighPC(DwarfCompileUnit &Unit, DIE &D,
2496 MCSymbol *Begin, MCSymbol *End) {
2497 Unit.addLabelAddress(D, dwarf::DW_AT_low_pc, Begin);
2498 if (DwarfVersion < 4)
2499 Unit.addLabelAddress(D, dwarf::DW_AT_high_pc, End);
2501 Unit.addLabelDelta(D, dwarf::DW_AT_high_pc, End, Begin);
2504 // Accelerator table mutators - add each name along with its companion
2505 // DIE to the proper table while ensuring that the name that we're going
2506 // to reference is in the string table. We do this since the names we
2507 // add may not only be identical to the names in the DIE.
2508 void DwarfDebug::addAccelName(StringRef Name, const DIE &Die) {
2509 if (!useDwarfAccelTables())
2511 AccelNames.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2515 void DwarfDebug::addAccelObjC(StringRef Name, const DIE &Die) {
2516 if (!useDwarfAccelTables())
2518 AccelObjC.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2522 void DwarfDebug::addAccelNamespace(StringRef Name, const DIE &Die) {
2523 if (!useDwarfAccelTables())
2525 AccelNamespace.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2529 void DwarfDebug::addAccelType(StringRef Name, const DIE &Die, char Flags) {
2530 if (!useDwarfAccelTables())
2532 AccelTypes.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),