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 (DS.getContext() && DS.isSubprogram()) {
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 DebugLoc DL = DebugLoc::getFromDILocation(IA);
1217 Scope = LScopes.findInlinedScope(DebugLoc::get(
1218 DL.getLine(), DL.getCol(), DV.getContext(), IA));
1220 Scope = LScopes.findLexicalScope(DV.getContext());
1221 // If variable scope is not found then skip this variable.
1225 Processed.insert(DV);
1226 assert(MInsn->isDebugValue() && "History must begin with debug value");
1227 DbgVariable *AbsVar = findAbstractVariable(DV, MInsn->getDebugLoc());
1228 DbgVariable *RegVar = new DbgVariable(DV, AbsVar, this);
1229 if (!addCurrentFnArgument(RegVar, Scope))
1230 addScopeVariable(Scope, RegVar);
1232 AbsVar->setMInsn(MInsn);
1234 // Simplify ranges that are fully coalesced.
1235 if (History.size() <= 1 ||
1236 (History.size() == 2 && MInsn->isIdenticalTo(History.back()))) {
1237 RegVar->setMInsn(MInsn);
1241 // Handle multiple DBG_VALUE instructions describing one variable.
1242 RegVar->setDotDebugLocOffset(DotDebugLocEntries.size());
1244 DotDebugLocEntries.resize(DotDebugLocEntries.size() + 1);
1245 DebugLocList &LocList = DotDebugLocEntries.back();
1247 Asm->GetTempSymbol("debug_loc", DotDebugLocEntries.size() - 1);
1248 SmallVector<DebugLocEntry, 4> &DebugLoc = LocList.List;
1249 for (SmallVectorImpl<const MachineInstr *>::const_iterator
1250 HI = History.begin(),
1253 const MachineInstr *Begin = *HI;
1254 assert(Begin->isDebugValue() && "Invalid History entry");
1256 // Check if DBG_VALUE is truncating a range.
1257 if (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() &&
1258 !Begin->getOperand(0).getReg())
1261 // Compute the range for a register location.
1262 const MCSymbol *FLabel = getLabelBeforeInsn(Begin);
1263 const MCSymbol *SLabel = nullptr;
1266 // If Begin is the last instruction in History then its value is valid
1267 // until the end of the function.
1268 SLabel = FunctionEndSym;
1270 const MachineInstr *End = HI[1];
1271 DEBUG(dbgs() << "DotDebugLoc Pair:\n"
1272 << "\t" << *Begin << "\t" << *End << "\n");
1273 if (End->isDebugValue())
1274 SLabel = getLabelBeforeInsn(End);
1276 // End is a normal instruction clobbering the range.
1277 SLabel = getLabelAfterInsn(End);
1278 assert(SLabel && "Forgot label after clobber instruction");
1283 // The value is valid until the next DBG_VALUE or clobber.
1284 DebugLocEntry Loc(FLabel, SLabel, getDebugLocValue(Begin), TheCU);
1285 if (DebugLoc.empty() || !DebugLoc.back().Merge(Loc))
1286 DebugLoc.push_back(std::move(Loc));
1290 // Collect info for variables that were optimized out.
1291 DIArray Variables = DISubprogram(FnScope->getScopeNode()).getVariables();
1292 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1293 DIVariable DV(Variables.getElement(i));
1294 if (!DV || !DV.isVariable() || !Processed.insert(DV))
1296 if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext()))
1297 addScopeVariable(Scope, new DbgVariable(DV, nullptr, this));
1301 // Return Label preceding the instruction.
1302 MCSymbol *DwarfDebug::getLabelBeforeInsn(const MachineInstr *MI) {
1303 MCSymbol *Label = LabelsBeforeInsn.lookup(MI);
1304 assert(Label && "Didn't insert label before instruction");
1308 // Return Label immediately following the instruction.
1309 MCSymbol *DwarfDebug::getLabelAfterInsn(const MachineInstr *MI) {
1310 return LabelsAfterInsn.lookup(MI);
1313 // Process beginning of an instruction.
1314 void DwarfDebug::beginInstruction(const MachineInstr *MI) {
1315 assert(CurMI == nullptr);
1317 // Check if source location changes, but ignore DBG_VALUE locations.
1318 if (!MI->isDebugValue()) {
1319 DebugLoc DL = MI->getDebugLoc();
1320 if (DL != PrevInstLoc && (!DL.isUnknown() || UnknownLocations)) {
1323 if (DL == PrologEndLoc) {
1324 Flags |= DWARF2_FLAG_PROLOGUE_END;
1325 PrologEndLoc = DebugLoc();
1327 if (PrologEndLoc.isUnknown())
1328 Flags |= DWARF2_FLAG_IS_STMT;
1330 if (!DL.isUnknown()) {
1331 const MDNode *Scope = DL.getScope(Asm->MF->getFunction()->getContext());
1332 recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags);
1334 recordSourceLine(0, 0, nullptr, 0);
1338 // Insert labels where requested.
1339 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1340 LabelsBeforeInsn.find(MI);
1343 if (I == LabelsBeforeInsn.end())
1346 // Label already assigned.
1351 PrevLabel = MMI->getContext().CreateTempSymbol();
1352 Asm->OutStreamer.EmitLabel(PrevLabel);
1354 I->second = PrevLabel;
1357 // Process end of an instruction.
1358 void DwarfDebug::endInstruction() {
1359 assert(CurMI != nullptr);
1360 // Don't create a new label after DBG_VALUE instructions.
1361 // They don't generate code.
1362 if (!CurMI->isDebugValue())
1363 PrevLabel = nullptr;
1365 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1366 LabelsAfterInsn.find(CurMI);
1370 if (I == LabelsAfterInsn.end())
1373 // Label already assigned.
1377 // We need a label after this instruction.
1379 PrevLabel = MMI->getContext().CreateTempSymbol();
1380 Asm->OutStreamer.EmitLabel(PrevLabel);
1382 I->second = PrevLabel;
1385 // Each LexicalScope has first instruction and last instruction to mark
1386 // beginning and end of a scope respectively. Create an inverse map that list
1387 // scopes starts (and ends) with an instruction. One instruction may start (or
1388 // end) multiple scopes. Ignore scopes that are not reachable.
1389 void DwarfDebug::identifyScopeMarkers() {
1390 SmallVector<LexicalScope *, 4> WorkList;
1391 WorkList.push_back(LScopes.getCurrentFunctionScope());
1392 while (!WorkList.empty()) {
1393 LexicalScope *S = WorkList.pop_back_val();
1395 const SmallVectorImpl<LexicalScope *> &Children = S->getChildren();
1396 if (!Children.empty())
1397 WorkList.append(Children.begin(), Children.end());
1399 if (S->isAbstractScope())
1402 for (const InsnRange &R : S->getRanges()) {
1403 assert(R.first && "InsnRange does not have first instruction!");
1404 assert(R.second && "InsnRange does not have second instruction!");
1405 requestLabelBeforeInsn(R.first);
1406 requestLabelAfterInsn(R.second);
1411 // Gather pre-function debug information. Assumes being called immediately
1412 // after the function entry point has been emitted.
1413 void DwarfDebug::beginFunction(const MachineFunction *MF) {
1416 // If there's no debug info for the function we're not going to do anything.
1417 if (!MMI->hasDebugInfo())
1420 // Grab the lexical scopes for the function, if we don't have any of those
1421 // then we're not going to be able to do anything.
1422 LScopes.initialize(*MF);
1423 if (LScopes.empty())
1426 assert(DbgValues.empty() && "DbgValues map wasn't cleaned!");
1428 // Make sure that each lexical scope will have a begin/end label.
1429 identifyScopeMarkers();
1431 // Set DwarfDwarfCompileUnitID in MCContext to the Compile Unit this function
1432 // belongs to so that we add to the correct per-cu line table in the
1434 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1435 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1436 assert(TheCU && "Unable to find compile unit!");
1437 if (Asm->OutStreamer.hasRawTextSupport())
1438 // Use a single line table if we are generating assembly.
1439 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1441 Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID());
1443 // Emit a label for the function so that we have a beginning address.
1444 FunctionBeginSym = Asm->GetTempSymbol("func_begin", Asm->getFunctionNumber());
1445 // Assumes in correct section after the entry point.
1446 Asm->OutStreamer.EmitLabel(FunctionBeginSym);
1448 // Collect user variables, find the end of the prologue.
1449 for (const auto &MBB : *MF) {
1450 for (const auto &MI : MBB) {
1451 if (MI.isDebugValue()) {
1452 assert(MI.getNumOperands() > 1 && "Invalid machine instruction!");
1453 // Keep track of user variables in order of appearance. Create the
1454 // empty history for each variable so that the order of keys in
1455 // DbgValues is correct. Actual history will be populated in
1456 // calculateDbgValueHistory() function.
1457 const MDNode *Var = MI.getDebugVariable();
1459 std::make_pair(Var, SmallVector<const MachineInstr *, 4>()));
1460 } else if (!MI.getFlag(MachineInstr::FrameSetup) &&
1461 PrologEndLoc.isUnknown() && !MI.getDebugLoc().isUnknown()) {
1462 // First known non-DBG_VALUE and non-frame setup location marks
1463 // the beginning of the function body.
1464 PrologEndLoc = MI.getDebugLoc();
1469 // Calculate history for local variables.
1470 calculateDbgValueHistory(MF, Asm->TM.getRegisterInfo(), DbgValues);
1472 // Request labels for the full history.
1473 for (auto &I : DbgValues) {
1474 const SmallVectorImpl<const MachineInstr *> &History = I.second;
1475 if (History.empty())
1478 // The first mention of a function argument gets the FunctionBeginSym
1479 // label, so arguments are visible when breaking at function entry.
1480 DIVariable DV(I.first);
1481 if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable &&
1482 getDISubprogram(DV.getContext()).describes(MF->getFunction()))
1483 LabelsBeforeInsn[History.front()] = FunctionBeginSym;
1485 for (const MachineInstr *MI : History) {
1486 if (MI->isDebugValue())
1487 requestLabelBeforeInsn(MI);
1489 requestLabelAfterInsn(MI);
1493 PrevInstLoc = DebugLoc();
1494 PrevLabel = FunctionBeginSym;
1496 // Record beginning of function.
1497 if (!PrologEndLoc.isUnknown()) {
1498 DebugLoc FnStartDL =
1499 PrologEndLoc.getFnDebugLoc(MF->getFunction()->getContext());
1501 FnStartDL.getLine(), FnStartDL.getCol(),
1502 FnStartDL.getScope(MF->getFunction()->getContext()),
1503 // We'd like to list the prologue as "not statements" but GDB behaves
1504 // poorly if we do that. Revisit this with caution/GDB (7.5+) testing.
1505 DWARF2_FLAG_IS_STMT);
1509 void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) {
1510 SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS];
1511 DIVariable DV = Var->getVariable();
1512 // Variables with positive arg numbers are parameters.
1513 if (unsigned ArgNum = DV.getArgNumber()) {
1514 // Keep all parameters in order at the start of the variable list to ensure
1515 // function types are correct (no out-of-order parameters)
1517 // This could be improved by only doing it for optimized builds (unoptimized
1518 // builds have the right order to begin with), searching from the back (this
1519 // would catch the unoptimized case quickly), or doing a binary search
1520 // rather than linear search.
1521 SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin();
1522 while (I != Vars.end()) {
1523 unsigned CurNum = (*I)->getVariable().getArgNumber();
1524 // A local (non-parameter) variable has been found, insert immediately
1528 // A later indexed parameter has been found, insert immediately before it.
1529 if (CurNum > ArgNum)
1533 Vars.insert(I, Var);
1537 Vars.push_back(Var);
1540 // Gather and emit post-function debug information.
1541 void DwarfDebug::endFunction(const MachineFunction *MF) {
1542 // Every beginFunction(MF) call should be followed by an endFunction(MF) call,
1543 // though the beginFunction may not be called at all.
1544 // We should handle both cases.
1548 assert(CurFn == MF);
1549 assert(CurFn != nullptr);
1551 if (!MMI->hasDebugInfo() || LScopes.empty()) {
1552 // If we don't have a lexical scope for this function then there will
1553 // be a hole in the range information. Keep note of this by setting the
1554 // previously used section to nullptr.
1555 PrevSection = nullptr;
1561 // Define end label for subprogram.
1562 FunctionEndSym = Asm->GetTempSymbol("func_end", Asm->getFunctionNumber());
1563 // Assumes in correct section after the entry point.
1564 Asm->OutStreamer.EmitLabel(FunctionEndSym);
1566 // Set DwarfDwarfCompileUnitID in MCContext to default value.
1567 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1569 SmallPtrSet<const MDNode *, 16> ProcessedVars;
1570 collectVariableInfo(ProcessedVars);
1572 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1573 DwarfCompileUnit &TheCU = *SPMap.lookup(FnScope->getScopeNode());
1575 // Construct abstract scopes.
1576 for (LexicalScope *AScope : LScopes.getAbstractScopesList()) {
1577 DISubprogram SP(AScope->getScopeNode());
1578 if (SP.isSubprogram()) {
1579 // Collect info for variables that were optimized out.
1580 DIArray Variables = SP.getVariables();
1581 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1582 DIVariable DV(Variables.getElement(i));
1583 if (!DV || !DV.isVariable() || !ProcessedVars.insert(DV))
1585 // Check that DbgVariable for DV wasn't created earlier, when
1586 // findAbstractVariable() was called for inlined instance of DV.
1587 LLVMContext &Ctx = DV->getContext();
1588 DIVariable CleanDV = cleanseInlinedVariable(DV, Ctx);
1589 if (AbstractVariables.lookup(CleanDV))
1591 if (LexicalScope *Scope = LScopes.findAbstractScope(DV.getContext()))
1592 addScopeVariable(Scope, new DbgVariable(DV, nullptr, this));
1595 if (ProcessedSPNodes.count(AScope->getScopeNode()) == 0)
1596 constructAbstractSubprogramScopeDIE(TheCU, AScope);
1599 DIE &CurFnDIE = constructSubprogramScopeDIE(TheCU, FnScope);
1600 if (!CurFn->getTarget().Options.DisableFramePointerElim(*CurFn))
1601 TheCU.addFlag(CurFnDIE, dwarf::DW_AT_APPLE_omit_frame_ptr);
1603 // Add the range of this function to the list of ranges for the CU.
1604 RangeSpan Span(FunctionBeginSym, FunctionEndSym);
1605 TheCU.addRange(std::move(Span));
1606 PrevSection = Asm->getCurrentSection();
1610 for (auto &I : ScopeVariables)
1611 DeleteContainerPointers(I.second);
1612 ScopeVariables.clear();
1613 DeleteContainerPointers(CurrentFnArguments);
1615 AbstractVariables.clear();
1616 LabelsBeforeInsn.clear();
1617 LabelsAfterInsn.clear();
1618 PrevLabel = nullptr;
1622 // Register a source line with debug info. Returns the unique label that was
1623 // emitted and which provides correspondence to the source line list.
1624 void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S,
1629 unsigned Discriminator = 0;
1631 DIDescriptor Scope(S);
1633 if (Scope.isCompileUnit()) {
1634 DICompileUnit CU(S);
1635 Fn = CU.getFilename();
1636 Dir = CU.getDirectory();
1637 } else if (Scope.isFile()) {
1639 Fn = F.getFilename();
1640 Dir = F.getDirectory();
1641 } else if (Scope.isSubprogram()) {
1643 Fn = SP.getFilename();
1644 Dir = SP.getDirectory();
1645 } else if (Scope.isLexicalBlockFile()) {
1646 DILexicalBlockFile DBF(S);
1647 Fn = DBF.getFilename();
1648 Dir = DBF.getDirectory();
1649 } else if (Scope.isLexicalBlock()) {
1650 DILexicalBlock DB(S);
1651 Fn = DB.getFilename();
1652 Dir = DB.getDirectory();
1653 Discriminator = DB.getDiscriminator();
1655 llvm_unreachable("Unexpected scope info");
1657 unsigned CUID = Asm->OutStreamer.getContext().getDwarfCompileUnitID();
1658 Src = static_cast<DwarfCompileUnit &>(*InfoHolder.getUnits()[CUID])
1659 .getOrCreateSourceID(Fn, Dir);
1661 Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0,
1665 //===----------------------------------------------------------------------===//
1667 //===----------------------------------------------------------------------===//
1669 // Emit initial Dwarf sections with a label at the start of each one.
1670 void DwarfDebug::emitSectionLabels() {
1671 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
1673 // Dwarf sections base addresses.
1674 DwarfInfoSectionSym =
1675 emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info");
1676 if (useSplitDwarf())
1677 DwarfInfoDWOSectionSym =
1678 emitSectionSym(Asm, TLOF.getDwarfInfoDWOSection(), "section_info_dwo");
1679 DwarfAbbrevSectionSym =
1680 emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev");
1681 if (useSplitDwarf())
1682 DwarfAbbrevDWOSectionSym = emitSectionSym(
1683 Asm, TLOF.getDwarfAbbrevDWOSection(), "section_abbrev_dwo");
1684 if (GenerateARangeSection)
1685 emitSectionSym(Asm, TLOF.getDwarfARangesSection());
1687 DwarfLineSectionSym =
1688 emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line");
1689 if (GenerateGnuPubSections) {
1690 DwarfGnuPubNamesSectionSym =
1691 emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection());
1692 DwarfGnuPubTypesSectionSym =
1693 emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection());
1694 } else if (HasDwarfPubSections) {
1695 emitSectionSym(Asm, TLOF.getDwarfPubNamesSection());
1696 emitSectionSym(Asm, TLOF.getDwarfPubTypesSection());
1699 DwarfStrSectionSym =
1700 emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string");
1701 if (useSplitDwarf()) {
1702 DwarfStrDWOSectionSym =
1703 emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string");
1704 DwarfAddrSectionSym =
1705 emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec");
1706 DwarfDebugLocSectionSym =
1707 emitSectionSym(Asm, TLOF.getDwarfLocDWOSection(), "skel_loc");
1709 DwarfDebugLocSectionSym =
1710 emitSectionSym(Asm, TLOF.getDwarfLocSection(), "section_debug_loc");
1711 DwarfDebugRangeSectionSym =
1712 emitSectionSym(Asm, TLOF.getDwarfRangesSection(), "debug_range");
1715 // Recursively emits a debug information entry.
1716 void DwarfDebug::emitDIE(DIE &Die) {
1717 // Get the abbreviation for this DIE.
1718 const DIEAbbrev &Abbrev = Die.getAbbrev();
1720 // Emit the code (index) for the abbreviation.
1721 if (Asm->isVerbose())
1722 Asm->OutStreamer.AddComment("Abbrev [" + Twine(Abbrev.getNumber()) +
1723 "] 0x" + Twine::utohexstr(Die.getOffset()) +
1724 ":0x" + Twine::utohexstr(Die.getSize()) + " " +
1725 dwarf::TagString(Abbrev.getTag()));
1726 Asm->EmitULEB128(Abbrev.getNumber());
1728 const SmallVectorImpl<DIEValue *> &Values = Die.getValues();
1729 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
1731 // Emit the DIE attribute values.
1732 for (unsigned i = 0, N = Values.size(); i < N; ++i) {
1733 dwarf::Attribute Attr = AbbrevData[i].getAttribute();
1734 dwarf::Form Form = AbbrevData[i].getForm();
1735 assert(Form && "Too many attributes for DIE (check abbreviation)");
1737 if (Asm->isVerbose()) {
1738 Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr));
1739 if (Attr == dwarf::DW_AT_accessibility)
1740 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(
1741 cast<DIEInteger>(Values[i])->getValue()));
1744 // Emit an attribute using the defined form.
1745 Values[i]->EmitValue(Asm, Form);
1748 // Emit the DIE children if any.
1749 if (Abbrev.hasChildren()) {
1750 for (auto &Child : Die.getChildren())
1753 Asm->OutStreamer.AddComment("End Of Children Mark");
1758 // Emit the debug info section.
1759 void DwarfDebug::emitDebugInfo() {
1760 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1762 Holder.emitUnits(this, DwarfAbbrevSectionSym);
1765 // Emit the abbreviation section.
1766 void DwarfDebug::emitAbbreviations() {
1767 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1769 Holder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection());
1772 // Emit the last address of the section and the end of the line matrix.
1773 void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) {
1774 // Define last address of section.
1775 Asm->OutStreamer.AddComment("Extended Op");
1778 Asm->OutStreamer.AddComment("Op size");
1779 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1);
1780 Asm->OutStreamer.AddComment("DW_LNE_set_address");
1781 Asm->EmitInt8(dwarf::DW_LNE_set_address);
1783 Asm->OutStreamer.AddComment("Section end label");
1785 Asm->OutStreamer.EmitSymbolValue(
1786 Asm->GetTempSymbol("section_end", SectionEnd),
1787 Asm->getDataLayout().getPointerSize());
1789 // Mark end of matrix.
1790 Asm->OutStreamer.AddComment("DW_LNE_end_sequence");
1796 // Emit visible names into a hashed accelerator table section.
1797 void DwarfDebug::emitAccelNames() {
1798 AccelNames.FinalizeTable(Asm, "Names");
1799 Asm->OutStreamer.SwitchSection(
1800 Asm->getObjFileLowering().getDwarfAccelNamesSection());
1801 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin");
1802 Asm->OutStreamer.EmitLabel(SectionBegin);
1804 // Emit the full data.
1805 AccelNames.Emit(Asm, SectionBegin, &InfoHolder);
1808 // Emit objective C classes and categories into a hashed accelerator table
1810 void DwarfDebug::emitAccelObjC() {
1811 AccelObjC.FinalizeTable(Asm, "ObjC");
1812 Asm->OutStreamer.SwitchSection(
1813 Asm->getObjFileLowering().getDwarfAccelObjCSection());
1814 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin");
1815 Asm->OutStreamer.EmitLabel(SectionBegin);
1817 // Emit the full data.
1818 AccelObjC.Emit(Asm, SectionBegin, &InfoHolder);
1821 // Emit namespace dies into a hashed accelerator table.
1822 void DwarfDebug::emitAccelNamespaces() {
1823 AccelNamespace.FinalizeTable(Asm, "namespac");
1824 Asm->OutStreamer.SwitchSection(
1825 Asm->getObjFileLowering().getDwarfAccelNamespaceSection());
1826 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin");
1827 Asm->OutStreamer.EmitLabel(SectionBegin);
1829 // Emit the full data.
1830 AccelNamespace.Emit(Asm, SectionBegin, &InfoHolder);
1833 // Emit type dies into a hashed accelerator table.
1834 void DwarfDebug::emitAccelTypes() {
1836 AccelTypes.FinalizeTable(Asm, "types");
1837 Asm->OutStreamer.SwitchSection(
1838 Asm->getObjFileLowering().getDwarfAccelTypesSection());
1839 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin");
1840 Asm->OutStreamer.EmitLabel(SectionBegin);
1842 // Emit the full data.
1843 AccelTypes.Emit(Asm, SectionBegin, &InfoHolder);
1846 // Public name handling.
1847 // The format for the various pubnames:
1849 // dwarf pubnames - offset/name pairs where the offset is the offset into the CU
1850 // for the DIE that is named.
1852 // gnu pubnames - offset/index value/name tuples where the offset is the offset
1853 // into the CU and the index value is computed according to the type of value
1854 // for the DIE that is named.
1856 // For type units the offset is the offset of the skeleton DIE. For split dwarf
1857 // it's the offset within the debug_info/debug_types dwo section, however, the
1858 // reference in the pubname header doesn't change.
1860 /// computeIndexValue - Compute the gdb index value for the DIE and CU.
1861 static dwarf::PubIndexEntryDescriptor computeIndexValue(DwarfUnit *CU,
1863 dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC;
1865 // We could have a specification DIE that has our most of our knowledge,
1866 // look for that now.
1867 DIEValue *SpecVal = Die->findAttribute(dwarf::DW_AT_specification);
1869 DIE &SpecDIE = cast<DIEEntry>(SpecVal)->getEntry();
1870 if (SpecDIE.findAttribute(dwarf::DW_AT_external))
1871 Linkage = dwarf::GIEL_EXTERNAL;
1872 } else if (Die->findAttribute(dwarf::DW_AT_external))
1873 Linkage = dwarf::GIEL_EXTERNAL;
1875 switch (Die->getTag()) {
1876 case dwarf::DW_TAG_class_type:
1877 case dwarf::DW_TAG_structure_type:
1878 case dwarf::DW_TAG_union_type:
1879 case dwarf::DW_TAG_enumeration_type:
1880 return dwarf::PubIndexEntryDescriptor(
1881 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus
1882 ? dwarf::GIEL_STATIC
1883 : dwarf::GIEL_EXTERNAL);
1884 case dwarf::DW_TAG_typedef:
1885 case dwarf::DW_TAG_base_type:
1886 case dwarf::DW_TAG_subrange_type:
1887 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC);
1888 case dwarf::DW_TAG_namespace:
1889 return dwarf::GIEK_TYPE;
1890 case dwarf::DW_TAG_subprogram:
1891 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage);
1892 case dwarf::DW_TAG_constant:
1893 case dwarf::DW_TAG_variable:
1894 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage);
1895 case dwarf::DW_TAG_enumerator:
1896 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE,
1897 dwarf::GIEL_STATIC);
1899 return dwarf::GIEK_NONE;
1903 /// emitDebugPubNames - Emit visible names into a debug pubnames section.
1905 void DwarfDebug::emitDebugPubNames(bool GnuStyle) {
1906 const MCSection *PSec =
1907 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection()
1908 : Asm->getObjFileLowering().getDwarfPubNamesSection();
1910 emitDebugPubSection(GnuStyle, PSec, "Names", &DwarfUnit::getGlobalNames);
1913 void DwarfDebug::emitDebugPubSection(
1914 bool GnuStyle, const MCSection *PSec, StringRef Name,
1915 const StringMap<const DIE *> &(DwarfUnit::*Accessor)() const) {
1916 for (const auto &NU : CUMap) {
1917 DwarfCompileUnit *TheU = NU.second;
1919 const auto &Globals = (TheU->*Accessor)();
1921 if (Globals.empty())
1924 if (auto Skeleton = static_cast<DwarfCompileUnit *>(TheU->getSkeleton()))
1926 unsigned ID = TheU->getUniqueID();
1928 // Start the dwarf pubnames section.
1929 Asm->OutStreamer.SwitchSection(PSec);
1932 Asm->OutStreamer.AddComment("Length of Public " + Name + " Info");
1933 MCSymbol *BeginLabel = Asm->GetTempSymbol("pub" + Name + "_begin", ID);
1934 MCSymbol *EndLabel = Asm->GetTempSymbol("pub" + Name + "_end", ID);
1935 Asm->EmitLabelDifference(EndLabel, BeginLabel, 4);
1937 Asm->OutStreamer.EmitLabel(BeginLabel);
1939 Asm->OutStreamer.AddComment("DWARF Version");
1940 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION);
1942 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info");
1943 Asm->EmitSectionOffset(TheU->getLabelBegin(), TheU->getSectionSym());
1945 Asm->OutStreamer.AddComment("Compilation Unit Length");
1946 Asm->EmitLabelDifference(TheU->getLabelEnd(), TheU->getLabelBegin(), 4);
1948 // Emit the pubnames for this compilation unit.
1949 for (const auto &GI : Globals) {
1950 const char *Name = GI.getKeyData();
1951 const DIE *Entity = GI.second;
1953 Asm->OutStreamer.AddComment("DIE offset");
1954 Asm->EmitInt32(Entity->getOffset());
1957 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheU, Entity);
1958 Asm->OutStreamer.AddComment(
1959 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " +
1960 dwarf::GDBIndexEntryLinkageString(Desc.Linkage));
1961 Asm->EmitInt8(Desc.toBits());
1964 Asm->OutStreamer.AddComment("External Name");
1965 Asm->OutStreamer.EmitBytes(StringRef(Name, GI.getKeyLength() + 1));
1968 Asm->OutStreamer.AddComment("End Mark");
1970 Asm->OutStreamer.EmitLabel(EndLabel);
1974 void DwarfDebug::emitDebugPubTypes(bool GnuStyle) {
1975 const MCSection *PSec =
1976 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection()
1977 : Asm->getObjFileLowering().getDwarfPubTypesSection();
1979 emitDebugPubSection(GnuStyle, PSec, "Types", &DwarfUnit::getGlobalTypes);
1982 // Emit visible names into a debug str section.
1983 void DwarfDebug::emitDebugStr() {
1984 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1985 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection());
1988 void DwarfDebug::emitDebugLocEntry(ByteStreamer &Streamer,
1989 const DebugLocEntry &Entry) {
1990 assert(Entry.getValues().size() == 1 &&
1991 "multi-value entries are not supported yet.");
1992 const DebugLocEntry::Value Value = Entry.getValues()[0];
1993 DIVariable DV(Value.getVariable());
1994 if (Value.isInt()) {
1995 DIBasicType BTy(resolve(DV.getType()));
1996 if (BTy.Verify() && (BTy.getEncoding() == dwarf::DW_ATE_signed ||
1997 BTy.getEncoding() == dwarf::DW_ATE_signed_char)) {
1998 Streamer.EmitInt8(dwarf::DW_OP_consts, "DW_OP_consts");
1999 Streamer.EmitSLEB128(Value.getInt());
2001 Streamer.EmitInt8(dwarf::DW_OP_constu, "DW_OP_constu");
2002 Streamer.EmitULEB128(Value.getInt());
2004 } else if (Value.isLocation()) {
2005 MachineLocation Loc = Value.getLoc();
2006 if (!DV.hasComplexAddress())
2008 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2010 // Complex address entry.
2011 unsigned N = DV.getNumAddrElements();
2013 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) {
2014 if (Loc.getOffset()) {
2016 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2017 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
2018 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
2019 Streamer.EmitSLEB128(DV.getAddrElement(1));
2021 // If first address element is OpPlus then emit
2022 // DW_OP_breg + Offset instead of DW_OP_reg + Offset.
2023 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1));
2024 Asm->EmitDwarfRegOp(Streamer, TLoc, DV.isIndirect());
2028 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2031 // Emit remaining complex address elements.
2032 for (; i < N; ++i) {
2033 uint64_t Element = DV.getAddrElement(i);
2034 if (Element == DIBuilder::OpPlus) {
2035 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
2036 Streamer.EmitULEB128(DV.getAddrElement(++i));
2037 } else if (Element == DIBuilder::OpDeref) {
2039 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
2041 llvm_unreachable("unknown Opcode found in complex address");
2045 // else ... ignore constant fp. There is not any good way to
2046 // to represent them here in dwarf.
2050 void DwarfDebug::emitDebugLocEntryLocation(const DebugLocEntry &Entry) {
2051 Asm->OutStreamer.AddComment("Loc expr size");
2052 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol();
2053 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol();
2054 Asm->EmitLabelDifference(end, begin, 2);
2055 Asm->OutStreamer.EmitLabel(begin);
2057 APByteStreamer Streamer(*Asm);
2058 emitDebugLocEntry(Streamer, Entry);
2060 Asm->OutStreamer.EmitLabel(end);
2063 // Emit locations into the debug loc section.
2064 void DwarfDebug::emitDebugLoc() {
2065 // Start the dwarf loc section.
2066 Asm->OutStreamer.SwitchSection(
2067 Asm->getObjFileLowering().getDwarfLocSection());
2068 unsigned char Size = Asm->getDataLayout().getPointerSize();
2069 for (const auto &DebugLoc : DotDebugLocEntries) {
2070 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2071 for (const auto &Entry : DebugLoc.List) {
2072 // Set up the range. This range is relative to the entry point of the
2073 // compile unit. This is a hard coded 0 for low_pc when we're emitting
2074 // ranges, or the DW_AT_low_pc on the compile unit otherwise.
2075 const DwarfCompileUnit *CU = Entry.getCU();
2076 if (CU->getRanges().size() == 1) {
2077 // Grab the begin symbol from the first range as our base.
2078 const MCSymbol *Base = CU->getRanges()[0].getStart();
2079 Asm->EmitLabelDifference(Entry.getBeginSym(), Base, Size);
2080 Asm->EmitLabelDifference(Entry.getEndSym(), Base, Size);
2082 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size);
2083 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size);
2086 emitDebugLocEntryLocation(Entry);
2088 Asm->OutStreamer.EmitIntValue(0, Size);
2089 Asm->OutStreamer.EmitIntValue(0, Size);
2093 void DwarfDebug::emitDebugLocDWO() {
2094 Asm->OutStreamer.SwitchSection(
2095 Asm->getObjFileLowering().getDwarfLocDWOSection());
2096 for (const auto &DebugLoc : DotDebugLocEntries) {
2097 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2098 for (const auto &Entry : DebugLoc.List) {
2099 // Just always use start_length for now - at least that's one address
2100 // rather than two. We could get fancier and try to, say, reuse an
2101 // address we know we've emitted elsewhere (the start of the function?
2102 // The start of the CU or CU subrange that encloses this range?)
2103 Asm->EmitInt8(dwarf::DW_LLE_start_length_entry);
2104 unsigned idx = AddrPool.getIndex(Entry.getBeginSym());
2105 Asm->EmitULEB128(idx);
2106 Asm->EmitLabelDifference(Entry.getEndSym(), Entry.getBeginSym(), 4);
2108 emitDebugLocEntryLocation(Entry);
2110 Asm->EmitInt8(dwarf::DW_LLE_end_of_list_entry);
2115 const MCSymbol *Start, *End;
2118 // Emit a debug aranges section, containing a CU lookup for any
2119 // address we can tie back to a CU.
2120 void DwarfDebug::emitDebugARanges() {
2121 // Start the dwarf aranges section.
2122 Asm->OutStreamer.SwitchSection(
2123 Asm->getObjFileLowering().getDwarfARangesSection());
2125 typedef DenseMap<DwarfCompileUnit *, std::vector<ArangeSpan>> SpansType;
2129 // Build a list of sections used.
2130 std::vector<const MCSection *> Sections;
2131 for (const auto &it : SectionMap) {
2132 const MCSection *Section = it.first;
2133 Sections.push_back(Section);
2136 // Sort the sections into order.
2137 // This is only done to ensure consistent output order across different runs.
2138 std::sort(Sections.begin(), Sections.end(), SectionSort);
2140 // Build a set of address spans, sorted by CU.
2141 for (const MCSection *Section : Sections) {
2142 SmallVector<SymbolCU, 8> &List = SectionMap[Section];
2143 if (List.size() < 2)
2146 // Sort the symbols by offset within the section.
2147 std::sort(List.begin(), List.end(),
2148 [&](const SymbolCU &A, const SymbolCU &B) {
2149 unsigned IA = A.Sym ? Asm->OutStreamer.GetSymbolOrder(A.Sym) : 0;
2150 unsigned IB = B.Sym ? Asm->OutStreamer.GetSymbolOrder(B.Sym) : 0;
2152 // Symbols with no order assigned should be placed at the end.
2153 // (e.g. section end labels)
2161 // If we have no section (e.g. common), just write out
2162 // individual spans for each symbol.
2164 for (const SymbolCU &Cur : List) {
2166 Span.Start = Cur.Sym;
2169 Spans[Cur.CU].push_back(Span);
2172 // Build spans between each label.
2173 const MCSymbol *StartSym = List[0].Sym;
2174 for (size_t n = 1, e = List.size(); n < e; n++) {
2175 const SymbolCU &Prev = List[n - 1];
2176 const SymbolCU &Cur = List[n];
2178 // Try and build the longest span we can within the same CU.
2179 if (Cur.CU != Prev.CU) {
2181 Span.Start = StartSym;
2183 Spans[Prev.CU].push_back(Span);
2190 unsigned PtrSize = Asm->getDataLayout().getPointerSize();
2192 // Build a list of CUs used.
2193 std::vector<DwarfCompileUnit *> CUs;
2194 for (const auto &it : Spans) {
2195 DwarfCompileUnit *CU = it.first;
2199 // Sort the CU list (again, to ensure consistent output order).
2200 std::sort(CUs.begin(), CUs.end(), [](const DwarfUnit *A, const DwarfUnit *B) {
2201 return A->getUniqueID() < B->getUniqueID();
2204 // Emit an arange table for each CU we used.
2205 for (DwarfCompileUnit *CU : CUs) {
2206 std::vector<ArangeSpan> &List = Spans[CU];
2208 // Emit size of content not including length itself.
2209 unsigned ContentSize =
2210 sizeof(int16_t) + // DWARF ARange version number
2211 sizeof(int32_t) + // Offset of CU in the .debug_info section
2212 sizeof(int8_t) + // Pointer Size (in bytes)
2213 sizeof(int8_t); // Segment Size (in bytes)
2215 unsigned TupleSize = PtrSize * 2;
2217 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple.
2219 OffsetToAlignment(sizeof(int32_t) + ContentSize, TupleSize);
2221 ContentSize += Padding;
2222 ContentSize += (List.size() + 1) * TupleSize;
2224 // For each compile unit, write the list of spans it covers.
2225 Asm->OutStreamer.AddComment("Length of ARange Set");
2226 Asm->EmitInt32(ContentSize);
2227 Asm->OutStreamer.AddComment("DWARF Arange version number");
2228 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION);
2229 Asm->OutStreamer.AddComment("Offset Into Debug Info Section");
2230 Asm->EmitSectionOffset(CU->getLocalLabelBegin(), CU->getLocalSectionSym());
2231 Asm->OutStreamer.AddComment("Address Size (in bytes)");
2232 Asm->EmitInt8(PtrSize);
2233 Asm->OutStreamer.AddComment("Segment Size (in bytes)");
2236 Asm->OutStreamer.EmitFill(Padding, 0xff);
2238 for (const ArangeSpan &Span : List) {
2239 Asm->EmitLabelReference(Span.Start, PtrSize);
2241 // Calculate the size as being from the span start to it's end.
2243 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize);
2245 // For symbols without an end marker (e.g. common), we
2246 // write a single arange entry containing just that one symbol.
2247 uint64_t Size = SymSize[Span.Start];
2251 Asm->OutStreamer.EmitIntValue(Size, PtrSize);
2255 Asm->OutStreamer.AddComment("ARange terminator");
2256 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2257 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2261 // Emit visible names into a debug ranges section.
2262 void DwarfDebug::emitDebugRanges() {
2263 // Start the dwarf ranges section.
2264 Asm->OutStreamer.SwitchSection(
2265 Asm->getObjFileLowering().getDwarfRangesSection());
2267 // Size for our labels.
2268 unsigned char Size = Asm->getDataLayout().getPointerSize();
2270 // Grab the specific ranges for the compile units in the module.
2271 for (const auto &I : CUMap) {
2272 DwarfCompileUnit *TheCU = I.second;
2274 // Iterate over the misc ranges for the compile units in the module.
2275 for (const RangeSpanList &List : TheCU->getRangeLists()) {
2276 // Emit our symbol so we can find the beginning of the range.
2277 Asm->OutStreamer.EmitLabel(List.getSym());
2279 for (const RangeSpan &Range : List.getRanges()) {
2280 const MCSymbol *Begin = Range.getStart();
2281 const MCSymbol *End = Range.getEnd();
2282 assert(Begin && "Range without a begin symbol?");
2283 assert(End && "Range without an end symbol?");
2284 if (TheCU->getRanges().size() == 1) {
2285 // Grab the begin symbol from the first range as our base.
2286 const MCSymbol *Base = TheCU->getRanges()[0].getStart();
2287 Asm->EmitLabelDifference(Begin, Base, Size);
2288 Asm->EmitLabelDifference(End, Base, Size);
2290 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2291 Asm->OutStreamer.EmitSymbolValue(End, Size);
2295 // And terminate the list with two 0 values.
2296 Asm->OutStreamer.EmitIntValue(0, Size);
2297 Asm->OutStreamer.EmitIntValue(0, Size);
2300 // Now emit a range for the CU itself.
2301 if (TheCU->getRanges().size() > 1) {
2302 Asm->OutStreamer.EmitLabel(
2303 Asm->GetTempSymbol("cu_ranges", TheCU->getUniqueID()));
2304 for (const RangeSpan &Range : TheCU->getRanges()) {
2305 const MCSymbol *Begin = Range.getStart();
2306 const MCSymbol *End = Range.getEnd();
2307 assert(Begin && "Range without a begin symbol?");
2308 assert(End && "Range without an end symbol?");
2309 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2310 Asm->OutStreamer.EmitSymbolValue(End, Size);
2312 // And terminate the list with two 0 values.
2313 Asm->OutStreamer.EmitIntValue(0, Size);
2314 Asm->OutStreamer.EmitIntValue(0, Size);
2319 // DWARF5 Experimental Separate Dwarf emitters.
2321 void DwarfDebug::initSkeletonUnit(const DwarfUnit &U, DIE &Die,
2322 std::unique_ptr<DwarfUnit> NewU) {
2323 NewU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name,
2324 U.getCUNode().getSplitDebugFilename());
2326 if (!CompilationDir.empty())
2327 NewU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
2329 addGnuPubAttributes(*NewU, Die);
2331 SkeletonHolder.addUnit(std::move(NewU));
2334 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list,
2335 // DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id,
2336 // DW_AT_addr_base, DW_AT_ranges_base.
2337 DwarfCompileUnit &DwarfDebug::constructSkeletonCU(const DwarfCompileUnit &CU) {
2339 auto OwnedUnit = make_unique<DwarfCompileUnit>(
2340 CU.getUniqueID(), CU.getCUNode(), Asm, this, &SkeletonHolder);
2341 DwarfCompileUnit &NewCU = *OwnedUnit;
2342 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
2343 DwarfInfoSectionSym);
2345 NewCU.initStmtList(DwarfLineSectionSym);
2347 initSkeletonUnit(CU, NewCU.getUnitDie(), std::move(OwnedUnit));
2352 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_dwo_name,
2354 DwarfTypeUnit &DwarfDebug::constructSkeletonTU(DwarfTypeUnit &TU) {
2355 DwarfCompileUnit &CU = static_cast<DwarfCompileUnit &>(
2356 *SkeletonHolder.getUnits()[TU.getCU().getUniqueID()]);
2358 auto OwnedUnit = make_unique<DwarfTypeUnit>(TU.getUniqueID(), CU, Asm, this,
2360 DwarfTypeUnit &NewTU = *OwnedUnit;
2361 NewTU.setTypeSignature(TU.getTypeSignature());
2362 NewTU.setType(nullptr);
2364 Asm->getObjFileLowering().getDwarfTypesSection(TU.getTypeSignature()));
2366 initSkeletonUnit(TU, NewTU.getUnitDie(), std::move(OwnedUnit));
2370 // Emit the .debug_info.dwo section for separated dwarf. This contains the
2371 // compile units that would normally be in debug_info.
2372 void DwarfDebug::emitDebugInfoDWO() {
2373 assert(useSplitDwarf() && "No split dwarf debug info?");
2374 // Don't pass an abbrev symbol, using a constant zero instead so as not to
2375 // emit relocations into the dwo file.
2376 InfoHolder.emitUnits(this, /* AbbrevSymbol */ nullptr);
2379 // Emit the .debug_abbrev.dwo section for separated dwarf. This contains the
2380 // abbreviations for the .debug_info.dwo section.
2381 void DwarfDebug::emitDebugAbbrevDWO() {
2382 assert(useSplitDwarf() && "No split dwarf?");
2383 InfoHolder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection());
2386 void DwarfDebug::emitDebugLineDWO() {
2387 assert(useSplitDwarf() && "No split dwarf?");
2388 Asm->OutStreamer.SwitchSection(
2389 Asm->getObjFileLowering().getDwarfLineDWOSection());
2390 SplitTypeUnitFileTable.Emit(Asm->OutStreamer);
2393 // Emit the .debug_str.dwo section for separated dwarf. This contains the
2394 // string section and is identical in format to traditional .debug_str
2396 void DwarfDebug::emitDebugStrDWO() {
2397 assert(useSplitDwarf() && "No split dwarf?");
2398 const MCSection *OffSec =
2399 Asm->getObjFileLowering().getDwarfStrOffDWOSection();
2400 const MCSymbol *StrSym = DwarfStrSectionSym;
2401 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(),
2405 MCDwarfDwoLineTable *DwarfDebug::getDwoLineTable(const DwarfCompileUnit &CU) {
2406 if (!useSplitDwarf())
2409 SplitTypeUnitFileTable.setCompilationDir(CU.getCUNode().getDirectory());
2410 return &SplitTypeUnitFileTable;
2413 static uint64_t makeTypeSignature(StringRef Identifier) {
2415 Hash.update(Identifier);
2416 // ... take the least significant 8 bytes and return those. Our MD5
2417 // implementation always returns its results in little endian, swap bytes
2419 MD5::MD5Result Result;
2421 return *reinterpret_cast<support::ulittle64_t *>(Result + 8);
2424 void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU,
2425 StringRef Identifier, DIE &RefDie,
2426 DICompositeType CTy) {
2427 // Fast path if we're building some type units and one has already used the
2428 // address pool we know we're going to throw away all this work anyway, so
2429 // don't bother building dependent types.
2430 if (!TypeUnitsUnderConstruction.empty() && AddrPool.hasBeenUsed())
2433 const DwarfTypeUnit *&TU = DwarfTypeUnits[CTy];
2435 CU.addDIETypeSignature(RefDie, *TU);
2439 bool TopLevelType = TypeUnitsUnderConstruction.empty();
2440 AddrPool.resetUsedFlag();
2443 make_unique<DwarfTypeUnit>(InfoHolder.getUnits().size(), CU, Asm, this,
2444 &InfoHolder, getDwoLineTable(CU));
2445 DwarfTypeUnit &NewTU = *OwnedUnit;
2446 DIE &UnitDie = NewTU.getUnitDie();
2448 TypeUnitsUnderConstruction.push_back(
2449 std::make_pair(std::move(OwnedUnit), CTy));
2451 NewTU.addUInt(UnitDie, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
2454 uint64_t Signature = makeTypeSignature(Identifier);
2455 NewTU.setTypeSignature(Signature);
2457 if (!useSplitDwarf())
2458 CU.applyStmtList(UnitDie);
2462 ? Asm->getObjFileLowering().getDwarfTypesDWOSection(Signature)
2463 : Asm->getObjFileLowering().getDwarfTypesSection(Signature));
2465 NewTU.setType(NewTU.createTypeDIE(CTy));
2468 auto TypeUnitsToAdd = std::move(TypeUnitsUnderConstruction);
2469 TypeUnitsUnderConstruction.clear();
2471 // Types referencing entries in the address table cannot be placed in type
2473 if (AddrPool.hasBeenUsed()) {
2475 // Remove all the types built while building this type.
2476 // This is pessimistic as some of these types might not be dependent on
2477 // the type that used an address.
2478 for (const auto &TU : TypeUnitsToAdd)
2479 DwarfTypeUnits.erase(TU.second);
2481 // Construct this type in the CU directly.
2482 // This is inefficient because all the dependent types will be rebuilt
2483 // from scratch, including building them in type units, discovering that
2484 // they depend on addresses, throwing them out and rebuilding them.
2485 CU.constructTypeDIE(RefDie, CTy);
2489 // If the type wasn't dependent on fission addresses, finish adding the type
2490 // and all its dependent types.
2491 for (auto &TU : TypeUnitsToAdd) {
2492 if (useSplitDwarf())
2493 TU.first->setSkeleton(constructSkeletonTU(*TU.first));
2494 InfoHolder.addUnit(std::move(TU.first));
2497 CU.addDIETypeSignature(RefDie, NewTU);
2500 void DwarfDebug::attachLowHighPC(DwarfCompileUnit &Unit, DIE &D,
2501 MCSymbol *Begin, MCSymbol *End) {
2502 Unit.addLabelAddress(D, dwarf::DW_AT_low_pc, Begin);
2503 if (DwarfVersion < 4)
2504 Unit.addLabelAddress(D, dwarf::DW_AT_high_pc, End);
2506 Unit.addLabelDelta(D, dwarf::DW_AT_high_pc, End, Begin);
2509 // Accelerator table mutators - add each name along with its companion
2510 // DIE to the proper table while ensuring that the name that we're going
2511 // to reference is in the string table. We do this since the names we
2512 // add may not only be identical to the names in the DIE.
2513 void DwarfDebug::addAccelName(StringRef Name, const DIE &Die) {
2514 if (!useDwarfAccelTables())
2516 AccelNames.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2520 void DwarfDebug::addAccelObjC(StringRef Name, const DIE &Die) {
2521 if (!useDwarfAccelTables())
2523 AccelObjC.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2527 void DwarfDebug::addAccelNamespace(StringRef Name, const DIE &Die) {
2528 if (!useDwarfAccelTables())
2530 AccelNamespace.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2534 void DwarfDebug::addAccelType(StringRef Name, const DIE &Die, char Flags) {
2535 if (!useDwarfAccelTables())
2537 AccelTypes.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),