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,
561 DISubprogram Sub, DIE &ScopeDIE) {
562 // We create children when the scope DIE is not null.
563 SmallVector<std::unique_ptr<DIE>, 8> Children;
564 if (DIE *ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children))
565 // The declaration will have the object_pointer, otherwise put it on the
566 // definition. This happens with ObjC blocks that have object_pointer on
567 // non-member functions.
568 if (!Sub.getFunctionDeclaration())
569 TheCU.addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, *ObjectPointer);
572 for (auto &I : Children)
573 ScopeDIE.addChild(std::move(I));
576 void DwarfDebug::constructAbstractSubprogramScopeDIE(DwarfCompileUnit &TheCU,
577 LexicalScope *Scope) {
578 assert(Scope && Scope->getScopeNode());
579 assert(Scope->isAbstractScope());
580 assert(!Scope->getInlinedAt());
582 DISubprogram Sub(Scope->getScopeNode());
584 ProcessedSPNodes.insert(Sub);
586 if (DIE *ScopeDIE = TheCU.getDIE(Sub)) {
587 AbstractSPDies.insert(std::make_pair(Sub, ScopeDIE));
588 createAndAddScopeChildren(TheCU, Scope, Sub, *ScopeDIE);
592 DIE &DwarfDebug::constructSubprogramScopeDIE(DwarfCompileUnit &TheCU,
593 LexicalScope *Scope) {
594 assert(Scope && Scope->getScopeNode());
595 assert(!Scope->getInlinedAt());
596 assert(!Scope->isAbstractScope());
597 assert(DIScope(Scope->getScopeNode()).isSubprogram());
599 DISubprogram Sub(Scope->getScopeNode());
601 ProcessedSPNodes.insert(Sub);
603 DIE &ScopeDIE = updateSubprogramScopeDIE(TheCU, Sub);
605 createAndAddScopeChildren(TheCU, Scope, Sub, ScopeDIE);
610 // Construct a DIE for this scope.
611 std::unique_ptr<DIE> DwarfDebug::constructScopeDIE(DwarfCompileUnit &TheCU,
612 LexicalScope *Scope) {
613 if (!Scope || !Scope->getScopeNode())
616 DIScope DS(Scope->getScopeNode());
618 assert((Scope->getInlinedAt() || !DS.isSubprogram()) &&
619 "Only handle inlined subprograms here, use "
620 "constructSubprogramScopeDIE for non-inlined "
623 SmallVector<std::unique_ptr<DIE>, 8> Children;
625 // We try to create the scope DIE first, then the children DIEs. This will
626 // avoid creating un-used children then removing them later when we find out
627 // the scope DIE is null.
628 std::unique_ptr<DIE> ScopeDIE;
629 if (Scope->getInlinedAt()) {
630 ScopeDIE = constructInlinedScopeDIE(TheCU, Scope);
633 // We create children when the scope DIE is not null.
634 createScopeChildrenDIE(TheCU, Scope, Children);
636 // Early exit when we know the scope DIE is going to be null.
637 if (isLexicalScopeDIENull(Scope))
640 // We create children here when we know the scope DIE is not going to be
641 // null and the children will be added to the scope DIE.
642 createScopeChildrenDIE(TheCU, Scope, Children);
644 // There is no need to emit empty lexical block DIE.
645 std::pair<ImportedEntityMap::const_iterator,
646 ImportedEntityMap::const_iterator> Range =
647 std::equal_range(ScopesWithImportedEntities.begin(),
648 ScopesWithImportedEntities.end(),
649 std::pair<const MDNode *, const MDNode *>(DS, nullptr),
651 if (Children.empty() && Range.first == Range.second)
653 ScopeDIE = constructLexicalScopeDIE(TheCU, Scope);
654 assert(ScopeDIE && "Scope DIE should not be null.");
655 for (ImportedEntityMap::const_iterator i = Range.first; i != Range.second;
657 constructImportedEntityDIE(TheCU, i->second, *ScopeDIE);
661 for (auto &I : Children)
662 ScopeDIE->addChild(std::move(I));
667 void DwarfDebug::addGnuPubAttributes(DwarfUnit &U, DIE &D) const {
668 if (!GenerateGnuPubSections)
671 U.addFlag(D, dwarf::DW_AT_GNU_pubnames);
674 // Create new DwarfCompileUnit for the given metadata node with tag
675 // DW_TAG_compile_unit.
676 DwarfCompileUnit &DwarfDebug::constructDwarfCompileUnit(DICompileUnit DIUnit) {
677 StringRef FN = DIUnit.getFilename();
678 CompilationDir = DIUnit.getDirectory();
680 auto OwnedUnit = make_unique<DwarfCompileUnit>(
681 InfoHolder.getUnits().size(), DIUnit, Asm, this, &InfoHolder);
682 DwarfCompileUnit &NewCU = *OwnedUnit;
683 DIE &Die = NewCU.getUnitDie();
684 InfoHolder.addUnit(std::move(OwnedUnit));
686 // LTO with assembly output shares a single line table amongst multiple CUs.
687 // To avoid the compilation directory being ambiguous, let the line table
688 // explicitly describe the directory of all files, never relying on the
689 // compilation directory.
690 if (!Asm->OutStreamer.hasRawTextSupport() || SingleCU)
691 Asm->OutStreamer.getContext().setMCLineTableCompilationDir(
692 NewCU.getUniqueID(), CompilationDir);
694 NewCU.addString(Die, dwarf::DW_AT_producer, DIUnit.getProducer());
695 NewCU.addUInt(Die, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
696 DIUnit.getLanguage());
697 NewCU.addString(Die, dwarf::DW_AT_name, FN);
699 if (!useSplitDwarf()) {
700 NewCU.initStmtList(DwarfLineSectionSym);
702 // If we're using split dwarf the compilation dir is going to be in the
703 // skeleton CU and so we don't need to duplicate it here.
704 if (!CompilationDir.empty())
705 NewCU.addString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
707 addGnuPubAttributes(NewCU, Die);
710 if (DIUnit.isOptimized())
711 NewCU.addFlag(Die, dwarf::DW_AT_APPLE_optimized);
713 StringRef Flags = DIUnit.getFlags();
715 NewCU.addString(Die, dwarf::DW_AT_APPLE_flags, Flags);
717 if (unsigned RVer = DIUnit.getRunTimeVersion())
718 NewCU.addUInt(Die, dwarf::DW_AT_APPLE_major_runtime_vers,
719 dwarf::DW_FORM_data1, RVer);
724 if (useSplitDwarf()) {
725 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoDWOSection(),
726 DwarfInfoDWOSectionSym);
727 NewCU.setSkeleton(constructSkeletonCU(NewCU));
729 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
730 DwarfInfoSectionSym);
732 CUMap.insert(std::make_pair(DIUnit, &NewCU));
733 CUDieMap.insert(std::make_pair(&Die, &NewCU));
737 // Construct subprogram DIE.
738 void DwarfDebug::constructSubprogramDIE(DwarfCompileUnit &TheCU,
740 // FIXME: We should only call this routine once, however, during LTO if a
741 // program is defined in multiple CUs we could end up calling it out of
742 // beginModule as we walk the CUs.
744 DwarfCompileUnit *&CURef = SPMap[N];
750 if (!SP.isDefinition())
751 // This is a method declaration which will be handled while constructing
755 DIE &SubprogramDie = *TheCU.getOrCreateSubprogramDIE(SP);
757 // Expose as a global name.
758 TheCU.addGlobalName(SP.getName(), SubprogramDie, resolve(SP.getContext()));
761 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
763 DIImportedEntity Module(N);
764 assert(Module.Verify());
765 if (DIE *D = TheCU.getOrCreateContextDIE(Module.getContext()))
766 constructImportedEntityDIE(TheCU, Module, *D);
769 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
770 const MDNode *N, DIE &Context) {
771 DIImportedEntity Module(N);
772 assert(Module.Verify());
773 return constructImportedEntityDIE(TheCU, Module, Context);
776 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
777 const DIImportedEntity &Module,
779 assert(Module.Verify() &&
780 "Use one of the MDNode * overloads to handle invalid metadata");
781 DIE &IMDie = TheCU.createAndAddDIE(Module.getTag(), Context, Module);
783 DIDescriptor Entity = resolve(Module.getEntity());
784 if (Entity.isNameSpace())
785 EntityDie = TheCU.getOrCreateNameSpace(DINameSpace(Entity));
786 else if (Entity.isSubprogram())
787 EntityDie = TheCU.getOrCreateSubprogramDIE(DISubprogram(Entity));
788 else if (Entity.isType())
789 EntityDie = TheCU.getOrCreateTypeDIE(DIType(Entity));
791 EntityDie = TheCU.getDIE(Entity);
792 TheCU.addSourceLine(IMDie, Module.getLineNumber(),
793 Module.getContext().getFilename(),
794 Module.getContext().getDirectory());
795 TheCU.addDIEEntry(IMDie, dwarf::DW_AT_import, *EntityDie);
796 StringRef Name = Module.getName();
798 TheCU.addString(IMDie, dwarf::DW_AT_name, Name);
801 // Emit all Dwarf sections that should come prior to the content. Create
802 // global DIEs and emit initial debug info sections. This is invoked by
803 // the target AsmPrinter.
804 void DwarfDebug::beginModule() {
805 if (DisableDebugInfoPrinting)
808 const Module *M = MMI->getModule();
810 // If module has named metadata anchors then use them, otherwise scan the
811 // module using debug info finder to collect debug info.
812 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
815 TypeIdentifierMap = generateDITypeIdentifierMap(CU_Nodes);
817 // Emit initial sections so we can reference labels later.
820 SingleCU = CU_Nodes->getNumOperands() == 1;
822 for (MDNode *N : CU_Nodes->operands()) {
823 DICompileUnit CUNode(N);
824 DwarfCompileUnit &CU = constructDwarfCompileUnit(CUNode);
825 DIArray ImportedEntities = CUNode.getImportedEntities();
826 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
827 ScopesWithImportedEntities.push_back(std::make_pair(
828 DIImportedEntity(ImportedEntities.getElement(i)).getContext(),
829 ImportedEntities.getElement(i)));
830 std::sort(ScopesWithImportedEntities.begin(),
831 ScopesWithImportedEntities.end(), less_first());
832 DIArray GVs = CUNode.getGlobalVariables();
833 for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i)
834 CU.createGlobalVariableDIE(DIGlobalVariable(GVs.getElement(i)));
835 DIArray SPs = CUNode.getSubprograms();
836 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i)
837 constructSubprogramDIE(CU, SPs.getElement(i));
838 DIArray EnumTypes = CUNode.getEnumTypes();
839 for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i)
840 CU.getOrCreateTypeDIE(EnumTypes.getElement(i));
841 DIArray RetainedTypes = CUNode.getRetainedTypes();
842 for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i) {
843 DIType Ty(RetainedTypes.getElement(i));
844 // The retained types array by design contains pointers to
845 // MDNodes rather than DIRefs. Unique them here.
846 DIType UniqueTy(resolve(Ty.getRef()));
847 CU.getOrCreateTypeDIE(UniqueTy);
849 // Emit imported_modules last so that the relevant context is already
851 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
852 constructImportedEntityDIE(CU, ImportedEntities.getElement(i));
855 // Tell MMI that we have debug info.
856 MMI->setDebugInfoAvailability(true);
858 // Prime section data.
859 SectionMap[Asm->getObjFileLowering().getTextSection()];
862 // Attach DW_AT_inline attribute with inlined subprogram DIEs.
863 void DwarfDebug::computeInlinedDIEs() {
864 // Attach DW_AT_inline attribute with inlined subprogram DIEs.
865 for (DIE *ISP : InlinedSubprogramDIEs)
866 FirstCU->addUInt(*ISP, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined);
868 for (const auto &AI : AbstractSPDies) {
869 DIE &ISP = *AI.second;
870 if (InlinedSubprogramDIEs.count(&ISP))
872 FirstCU->addUInt(ISP, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined);
876 // Collect info for variables that were optimized out.
877 void DwarfDebug::collectDeadVariables() {
878 const Module *M = MMI->getModule();
880 if (NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu")) {
881 for (MDNode *N : CU_Nodes->operands()) {
882 DICompileUnit TheCU(N);
883 DIArray Subprograms = TheCU.getSubprograms();
884 for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) {
885 DISubprogram SP(Subprograms.getElement(i));
886 if (ProcessedSPNodes.count(SP) != 0)
888 if (!SP.isSubprogram())
890 if (!SP.isDefinition())
892 DIArray Variables = SP.getVariables();
893 if (Variables.getNumElements() == 0)
896 // Construct subprogram DIE and add variables DIEs.
897 DwarfCompileUnit *SPCU =
898 static_cast<DwarfCompileUnit *>(CUMap.lookup(TheCU));
899 assert(SPCU && "Unable to find Compile Unit!");
900 // FIXME: See the comment in constructSubprogramDIE about duplicate
902 constructSubprogramDIE(*SPCU, SP);
903 DIE *SPDIE = SPCU->getDIE(SP);
904 for (unsigned vi = 0, ve = Variables.getNumElements(); vi != ve; ++vi) {
905 DIVariable DV(Variables.getElement(vi));
906 if (!DV.isVariable())
908 DbgVariable NewVar(DV, nullptr, this);
909 SPDIE->addChild(SPCU->constructVariableDIE(NewVar));
916 void DwarfDebug::finalizeModuleInfo() {
917 // Collect info for variables that were optimized out.
918 collectDeadVariables();
920 // Attach DW_AT_inline attribute with inlined subprogram DIEs.
921 computeInlinedDIEs();
923 // Handle anything that needs to be done on a per-unit basis after
924 // all other generation.
925 for (const auto &TheU : getUnits()) {
926 // Emit DW_AT_containing_type attribute to connect types with their
927 // vtable holding type.
928 TheU->constructContainingTypeDIEs();
930 // Add CU specific attributes if we need to add any.
931 if (TheU->getUnitDie().getTag() == dwarf::DW_TAG_compile_unit) {
932 // If we're splitting the dwarf out now that we've got the entire
933 // CU then add the dwo id to it.
934 DwarfCompileUnit *SkCU =
935 static_cast<DwarfCompileUnit *>(TheU->getSkeleton());
936 if (useSplitDwarf()) {
937 // Emit a unique identifier for this CU.
938 uint64_t ID = DIEHash(Asm).computeCUSignature(TheU->getUnitDie());
939 TheU->addUInt(TheU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
940 dwarf::DW_FORM_data8, ID);
941 SkCU->addUInt(SkCU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
942 dwarf::DW_FORM_data8, ID);
944 // We don't keep track of which addresses are used in which CU so this
945 // is a bit pessimistic under LTO.
946 if (!AddrPool.isEmpty())
947 addSectionLabel(*Asm, *SkCU, SkCU->getUnitDie(),
948 dwarf::DW_AT_GNU_addr_base, DwarfAddrSectionSym,
949 DwarfAddrSectionSym);
950 if (!TheU->getRangeLists().empty())
951 addSectionLabel(*Asm, *SkCU, SkCU->getUnitDie(),
952 dwarf::DW_AT_GNU_ranges_base,
953 DwarfDebugRangeSectionSym, DwarfDebugRangeSectionSym);
956 // If we have code split among multiple sections or non-contiguous
957 // ranges of code then emit a DW_AT_ranges attribute on the unit that will
958 // remain in the .o file, otherwise add a DW_AT_low_pc.
959 // FIXME: We should use ranges allow reordering of code ala
960 // .subsections_via_symbols in mach-o. This would mean turning on
961 // ranges for all subprogram DIEs for mach-o.
962 DwarfCompileUnit &U =
963 SkCU ? *SkCU : static_cast<DwarfCompileUnit &>(*TheU);
964 unsigned NumRanges = TheU->getRanges().size();
967 addSectionLabel(*Asm, U, U.getUnitDie(), dwarf::DW_AT_ranges,
968 Asm->GetTempSymbol("cu_ranges", U.getUniqueID()),
969 DwarfDebugRangeSectionSym);
971 // A DW_AT_low_pc attribute may also be specified in combination with
972 // DW_AT_ranges to specify the default base address for use in
973 // location lists (see Section 2.6.2) and range lists (see Section
975 U.addUInt(U.getUnitDie(), dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr,
978 RangeSpan &Range = TheU->getRanges().back();
979 U.addLocalLabelAddress(U.getUnitDie(), dwarf::DW_AT_low_pc,
981 U.addLabelDelta(U.getUnitDie(), dwarf::DW_AT_high_pc, Range.getEnd(),
988 // Compute DIE offsets and sizes.
989 InfoHolder.computeSizeAndOffsets();
991 SkeletonHolder.computeSizeAndOffsets();
994 void DwarfDebug::endSections() {
995 // Filter labels by section.
996 for (const SymbolCU &SCU : ArangeLabels) {
997 if (SCU.Sym->isInSection()) {
998 // Make a note of this symbol and it's section.
999 const MCSection *Section = &SCU.Sym->getSection();
1000 if (!Section->getKind().isMetadata())
1001 SectionMap[Section].push_back(SCU);
1003 // Some symbols (e.g. common/bss on mach-o) can have no section but still
1004 // appear in the output. This sucks as we rely on sections to build
1005 // arange spans. We can do it without, but it's icky.
1006 SectionMap[nullptr].push_back(SCU);
1010 // Build a list of sections used.
1011 std::vector<const MCSection *> Sections;
1012 for (const auto &it : SectionMap) {
1013 const MCSection *Section = it.first;
1014 Sections.push_back(Section);
1017 // Sort the sections into order.
1018 // This is only done to ensure consistent output order across different runs.
1019 std::sort(Sections.begin(), Sections.end(), SectionSort);
1021 // Add terminating symbols for each section.
1022 for (unsigned ID = 0, E = Sections.size(); ID != E; ID++) {
1023 const MCSection *Section = Sections[ID];
1024 MCSymbol *Sym = nullptr;
1027 // We can't call MCSection::getLabelEndName, as it's only safe to do so
1028 // if we know the section name up-front. For user-created sections, the
1029 // resulting label may not be valid to use as a label. (section names can
1030 // use a greater set of characters on some systems)
1031 Sym = Asm->GetTempSymbol("debug_end", ID);
1032 Asm->OutStreamer.SwitchSection(Section);
1033 Asm->OutStreamer.EmitLabel(Sym);
1036 // Insert a final terminator.
1037 SectionMap[Section].push_back(SymbolCU(nullptr, Sym));
1041 // Emit all Dwarf sections that should come after the content.
1042 void DwarfDebug::endModule() {
1043 assert(CurFn == nullptr);
1044 assert(CurMI == nullptr);
1049 // End any existing sections.
1050 // TODO: Does this need to happen?
1053 // Finalize the debug info for the module.
1054 finalizeModuleInfo();
1058 // Emit all the DIEs into a debug info section.
1061 // Corresponding abbreviations into a abbrev section.
1062 emitAbbreviations();
1064 // Emit info into a debug aranges section.
1065 if (GenerateARangeSection)
1068 // Emit info into a debug ranges section.
1071 if (useSplitDwarf()) {
1074 emitDebugAbbrevDWO();
1076 // Emit DWO addresses.
1077 AddrPool.emit(*Asm, Asm->getObjFileLowering().getDwarfAddrSection());
1080 // Emit info into a debug loc section.
1083 // Emit info into the dwarf accelerator table sections.
1084 if (useDwarfAccelTables()) {
1087 emitAccelNamespaces();
1091 // Emit the pubnames and pubtypes sections if requested.
1092 if (HasDwarfPubSections) {
1093 emitDebugPubNames(GenerateGnuPubSections);
1094 emitDebugPubTypes(GenerateGnuPubSections);
1100 // Reset these for the next Module if we have one.
1104 // Find abstract variable, if any, associated with Var.
1105 DbgVariable *DwarfDebug::findAbstractVariable(DIVariable &DV,
1106 DebugLoc ScopeLoc) {
1107 LLVMContext &Ctx = DV->getContext();
1108 // More then one inlined variable corresponds to one abstract variable.
1109 DIVariable Var = cleanseInlinedVariable(DV, Ctx);
1110 DbgVariable *AbsDbgVariable = AbstractVariables.lookup(Var);
1112 return AbsDbgVariable;
1114 LexicalScope *Scope = LScopes.findAbstractScope(ScopeLoc.getScope(Ctx));
1118 AbsDbgVariable = new DbgVariable(Var, nullptr, this);
1119 addScopeVariable(Scope, AbsDbgVariable);
1120 AbstractVariables[Var] = AbsDbgVariable;
1121 return AbsDbgVariable;
1124 // If Var is a current function argument then add it to CurrentFnArguments list.
1125 bool DwarfDebug::addCurrentFnArgument(DbgVariable *Var, LexicalScope *Scope) {
1126 if (!LScopes.isCurrentFunctionScope(Scope))
1128 DIVariable DV = Var->getVariable();
1129 if (DV.getTag() != dwarf::DW_TAG_arg_variable)
1131 unsigned ArgNo = DV.getArgNumber();
1135 size_t Size = CurrentFnArguments.size();
1137 CurrentFnArguments.resize(CurFn->getFunction()->arg_size());
1138 // llvm::Function argument size is not good indicator of how many
1139 // arguments does the function have at source level.
1141 CurrentFnArguments.resize(ArgNo * 2);
1142 CurrentFnArguments[ArgNo - 1] = Var;
1146 // Collect variable information from side table maintained by MMI.
1147 void DwarfDebug::collectVariableInfoFromMMITable(
1148 SmallPtrSet<const MDNode *, 16> &Processed) {
1149 for (const auto &VI : MMI->getVariableDbgInfo()) {
1152 Processed.insert(VI.Var);
1153 DIVariable DV(VI.Var);
1154 LexicalScope *Scope = LScopes.findLexicalScope(VI.Loc);
1156 // If variable scope is not found then skip this variable.
1160 DbgVariable *AbsDbgVariable = findAbstractVariable(DV, VI.Loc);
1161 DbgVariable *RegVar = new DbgVariable(DV, AbsDbgVariable, this);
1162 RegVar->setFrameIndex(VI.Slot);
1163 if (!addCurrentFnArgument(RegVar, Scope))
1164 addScopeVariable(Scope, RegVar);
1166 AbsDbgVariable->setFrameIndex(VI.Slot);
1170 // Get .debug_loc entry for the instruction range starting at MI.
1171 static DebugLocEntry::Value getDebugLocValue(const MachineInstr *MI) {
1172 const MDNode *Var = MI->getDebugVariable();
1174 assert(MI->getNumOperands() == 3);
1175 if (MI->getOperand(0).isReg()) {
1176 MachineLocation MLoc;
1177 // If the second operand is an immediate, this is a
1178 // register-indirect address.
1179 if (!MI->getOperand(1).isImm())
1180 MLoc.set(MI->getOperand(0).getReg());
1182 MLoc.set(MI->getOperand(0).getReg(), MI->getOperand(1).getImm());
1183 return DebugLocEntry::Value(Var, MLoc);
1185 if (MI->getOperand(0).isImm())
1186 return DebugLocEntry::Value(Var, MI->getOperand(0).getImm());
1187 if (MI->getOperand(0).isFPImm())
1188 return DebugLocEntry::Value(Var, MI->getOperand(0).getFPImm());
1189 if (MI->getOperand(0).isCImm())
1190 return DebugLocEntry::Value(Var, MI->getOperand(0).getCImm());
1192 llvm_unreachable("Unexpected 3 operand DBG_VALUE instruction!");
1195 // Find variables for each lexical scope.
1197 DwarfDebug::collectVariableInfo(SmallPtrSet<const MDNode *, 16> &Processed) {
1198 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1199 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1201 // Grab the variable info that was squirreled away in the MMI side-table.
1202 collectVariableInfoFromMMITable(Processed);
1204 for (const MDNode *Var : UserVariables) {
1205 if (Processed.count(Var))
1208 // History contains relevant DBG_VALUE instructions for Var and instructions
1210 SmallVectorImpl<const MachineInstr *> &History = DbgValues[Var];
1211 if (History.empty())
1213 const MachineInstr *MInsn = History.front();
1216 LexicalScope *Scope = nullptr;
1217 if (DV.getTag() == dwarf::DW_TAG_arg_variable &&
1218 DISubprogram(DV.getContext()).describes(CurFn->getFunction()))
1219 Scope = LScopes.getCurrentFunctionScope();
1220 else if (MDNode *IA = DV.getInlinedAt())
1221 Scope = LScopes.findInlinedScope(DebugLoc::getFromDILocation(IA));
1223 Scope = LScopes.findLexicalScope(cast<MDNode>(DV->getOperand(1)));
1224 // If variable scope is not found then skip this variable.
1228 Processed.insert(DV);
1229 assert(MInsn->isDebugValue() && "History must begin with debug value");
1230 DbgVariable *AbsVar = findAbstractVariable(DV, MInsn->getDebugLoc());
1231 DbgVariable *RegVar = new DbgVariable(DV, AbsVar, this);
1232 if (!addCurrentFnArgument(RegVar, Scope))
1233 addScopeVariable(Scope, RegVar);
1235 AbsVar->setMInsn(MInsn);
1237 // Simplify ranges that are fully coalesced.
1238 if (History.size() <= 1 ||
1239 (History.size() == 2 && MInsn->isIdenticalTo(History.back()))) {
1240 RegVar->setMInsn(MInsn);
1244 // Handle multiple DBG_VALUE instructions describing one variable.
1245 RegVar->setDotDebugLocOffset(DotDebugLocEntries.size());
1247 DotDebugLocEntries.resize(DotDebugLocEntries.size() + 1);
1248 DebugLocList &LocList = DotDebugLocEntries.back();
1250 Asm->GetTempSymbol("debug_loc", DotDebugLocEntries.size() - 1);
1251 SmallVector<DebugLocEntry, 4> &DebugLoc = LocList.List;
1252 for (SmallVectorImpl<const MachineInstr *>::const_iterator
1253 HI = History.begin(),
1256 const MachineInstr *Begin = *HI;
1257 assert(Begin->isDebugValue() && "Invalid History entry");
1259 // Check if DBG_VALUE is truncating a range.
1260 if (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() &&
1261 !Begin->getOperand(0).getReg())
1264 // Compute the range for a register location.
1265 const MCSymbol *FLabel = getLabelBeforeInsn(Begin);
1266 const MCSymbol *SLabel = nullptr;
1269 // If Begin is the last instruction in History then its value is valid
1270 // until the end of the function.
1271 SLabel = FunctionEndSym;
1273 const MachineInstr *End = HI[1];
1274 DEBUG(dbgs() << "DotDebugLoc Pair:\n"
1275 << "\t" << *Begin << "\t" << *End << "\n");
1276 if (End->isDebugValue())
1277 SLabel = getLabelBeforeInsn(End);
1279 // End is a normal instruction clobbering the range.
1280 SLabel = getLabelAfterInsn(End);
1281 assert(SLabel && "Forgot label after clobber instruction");
1286 // The value is valid until the next DBG_VALUE or clobber.
1287 DebugLocEntry Loc(FLabel, SLabel, getDebugLocValue(Begin), TheCU);
1288 if (DebugLoc.empty() || !DebugLoc.back().Merge(Loc))
1289 DebugLoc.push_back(std::move(Loc));
1293 // Collect info for variables that were optimized out.
1294 DIArray Variables = DISubprogram(FnScope->getScopeNode()).getVariables();
1295 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1296 DIVariable DV(Variables.getElement(i));
1297 if (!DV || !DV.isVariable() || !Processed.insert(DV))
1299 if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext()))
1300 addScopeVariable(Scope, new DbgVariable(DV, nullptr, this));
1304 // Return Label preceding the instruction.
1305 MCSymbol *DwarfDebug::getLabelBeforeInsn(const MachineInstr *MI) {
1306 MCSymbol *Label = LabelsBeforeInsn.lookup(MI);
1307 assert(Label && "Didn't insert label before instruction");
1311 // Return Label immediately following the instruction.
1312 MCSymbol *DwarfDebug::getLabelAfterInsn(const MachineInstr *MI) {
1313 return LabelsAfterInsn.lookup(MI);
1316 // Process beginning of an instruction.
1317 void DwarfDebug::beginInstruction(const MachineInstr *MI) {
1318 assert(CurMI == nullptr);
1320 // Check if source location changes, but ignore DBG_VALUE locations.
1321 if (!MI->isDebugValue()) {
1322 DebugLoc DL = MI->getDebugLoc();
1323 if (DL != PrevInstLoc && (!DL.isUnknown() || UnknownLocations)) {
1326 if (DL == PrologEndLoc) {
1327 Flags |= DWARF2_FLAG_PROLOGUE_END;
1328 PrologEndLoc = DebugLoc();
1330 if (PrologEndLoc.isUnknown())
1331 Flags |= DWARF2_FLAG_IS_STMT;
1333 if (!DL.isUnknown()) {
1334 const MDNode *Scope = DL.getScope(Asm->MF->getFunction()->getContext());
1335 recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags);
1337 recordSourceLine(0, 0, nullptr, 0);
1341 // Insert labels where requested.
1342 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1343 LabelsBeforeInsn.find(MI);
1346 if (I == LabelsBeforeInsn.end())
1349 // Label already assigned.
1354 PrevLabel = MMI->getContext().CreateTempSymbol();
1355 Asm->OutStreamer.EmitLabel(PrevLabel);
1357 I->second = PrevLabel;
1360 // Process end of an instruction.
1361 void DwarfDebug::endInstruction() {
1362 assert(CurMI != nullptr);
1363 // Don't create a new label after DBG_VALUE instructions.
1364 // They don't generate code.
1365 if (!CurMI->isDebugValue())
1366 PrevLabel = nullptr;
1368 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1369 LabelsAfterInsn.find(CurMI);
1373 if (I == LabelsAfterInsn.end())
1376 // Label already assigned.
1380 // We need a label after this instruction.
1382 PrevLabel = MMI->getContext().CreateTempSymbol();
1383 Asm->OutStreamer.EmitLabel(PrevLabel);
1385 I->second = PrevLabel;
1388 // Each LexicalScope has first instruction and last instruction to mark
1389 // beginning and end of a scope respectively. Create an inverse map that list
1390 // scopes starts (and ends) with an instruction. One instruction may start (or
1391 // end) multiple scopes. Ignore scopes that are not reachable.
1392 void DwarfDebug::identifyScopeMarkers() {
1393 SmallVector<LexicalScope *, 4> WorkList;
1394 WorkList.push_back(LScopes.getCurrentFunctionScope());
1395 while (!WorkList.empty()) {
1396 LexicalScope *S = WorkList.pop_back_val();
1398 const SmallVectorImpl<LexicalScope *> &Children = S->getChildren();
1399 if (!Children.empty())
1400 WorkList.append(Children.begin(), Children.end());
1402 if (S->isAbstractScope())
1405 for (const InsnRange &R : S->getRanges()) {
1406 assert(R.first && "InsnRange does not have first instruction!");
1407 assert(R.second && "InsnRange does not have second instruction!");
1408 requestLabelBeforeInsn(R.first);
1409 requestLabelAfterInsn(R.second);
1414 // Gather pre-function debug information. Assumes being called immediately
1415 // after the function entry point has been emitted.
1416 void DwarfDebug::beginFunction(const MachineFunction *MF) {
1419 // If there's no debug info for the function we're not going to do anything.
1420 if (!MMI->hasDebugInfo())
1423 // Grab the lexical scopes for the function, if we don't have any of those
1424 // then we're not going to be able to do anything.
1425 LScopes.initialize(*MF);
1426 if (LScopes.empty())
1429 assert(UserVariables.empty() && DbgValues.empty() && "Maps weren't cleaned");
1431 // Make sure that each lexical scope will have a begin/end label.
1432 identifyScopeMarkers();
1434 // Set DwarfDwarfCompileUnitID in MCContext to the Compile Unit this function
1435 // belongs to so that we add to the correct per-cu line table in the
1437 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1438 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1439 assert(TheCU && "Unable to find compile unit!");
1440 if (Asm->OutStreamer.hasRawTextSupport())
1441 // Use a single line table if we are generating assembly.
1442 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1444 Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID());
1446 // Emit a label for the function so that we have a beginning address.
1447 FunctionBeginSym = Asm->GetTempSymbol("func_begin", Asm->getFunctionNumber());
1448 // Assumes in correct section after the entry point.
1449 Asm->OutStreamer.EmitLabel(FunctionBeginSym);
1451 // Collect user variables, find the end of the prologue.
1452 for (const auto &MBB : *MF) {
1453 for (const auto &MI : MBB) {
1454 if (MI.isDebugValue()) {
1455 assert(MI.getNumOperands() > 1 && "Invalid machine instruction!");
1456 // Keep track of user variables in order of appearance. Store the set
1457 // of variables we've already seen as a set of keys in DbgValues.
1458 const MDNode *Var = MI.getDebugVariable();
1459 auto IterPair = DbgValues.insert(
1460 std::make_pair(Var, SmallVector<const MachineInstr *, 4>()));
1461 if (IterPair.second)
1462 UserVariables.push_back(Var);
1463 } else if (!MI.getFlag(MachineInstr::FrameSetup) &&
1464 PrologEndLoc.isUnknown() && !MI.getDebugLoc().isUnknown()) {
1465 // First known non-DBG_VALUE and non-frame setup location marks
1466 // the beginning of the function body.
1467 PrologEndLoc = MI.getDebugLoc();
1472 // Calculate history for local variables.
1473 calculateDbgValueHistory(MF, Asm->TM.getRegisterInfo(), DbgValues);
1475 // Request labels for the full history.
1476 for (auto &I : DbgValues) {
1477 const SmallVectorImpl<const MachineInstr *> &History = I.second;
1478 if (History.empty())
1481 // The first mention of a function argument gets the FunctionBeginSym
1482 // label, so arguments are visible when breaking at function entry.
1483 DIVariable DV(I.first);
1484 if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable &&
1485 getDISubprogram(DV.getContext()).describes(MF->getFunction()))
1486 LabelsBeforeInsn[History.front()] = FunctionBeginSym;
1488 for (const MachineInstr *MI : History) {
1489 if (MI->isDebugValue())
1490 requestLabelBeforeInsn(MI);
1492 requestLabelAfterInsn(MI);
1496 PrevInstLoc = DebugLoc();
1497 PrevLabel = FunctionBeginSym;
1499 // Record beginning of function.
1500 if (!PrologEndLoc.isUnknown()) {
1501 DebugLoc FnStartDL =
1502 PrologEndLoc.getFnDebugLoc(MF->getFunction()->getContext());
1504 FnStartDL.getLine(), FnStartDL.getCol(),
1505 FnStartDL.getScope(MF->getFunction()->getContext()),
1506 // We'd like to list the prologue as "not statements" but GDB behaves
1507 // poorly if we do that. Revisit this with caution/GDB (7.5+) testing.
1508 DWARF2_FLAG_IS_STMT);
1512 void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) {
1513 SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS];
1514 DIVariable DV = Var->getVariable();
1515 // Variables with positive arg numbers are parameters.
1516 if (unsigned ArgNum = DV.getArgNumber()) {
1517 // Keep all parameters in order at the start of the variable list to ensure
1518 // function types are correct (no out-of-order parameters)
1520 // This could be improved by only doing it for optimized builds (unoptimized
1521 // builds have the right order to begin with), searching from the back (this
1522 // would catch the unoptimized case quickly), or doing a binary search
1523 // rather than linear search.
1524 SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin();
1525 while (I != Vars.end()) {
1526 unsigned CurNum = (*I)->getVariable().getArgNumber();
1527 // A local (non-parameter) variable has been found, insert immediately
1531 // A later indexed parameter has been found, insert immediately before it.
1532 if (CurNum > ArgNum)
1536 Vars.insert(I, Var);
1540 Vars.push_back(Var);
1543 // Gather and emit post-function debug information.
1544 void DwarfDebug::endFunction(const MachineFunction *MF) {
1545 // Every beginFunction(MF) call should be followed by an endFunction(MF) call,
1546 // though the beginFunction may not be called at all.
1547 // We should handle both cases.
1551 assert(CurFn == MF);
1552 assert(CurFn != nullptr);
1554 if (!MMI->hasDebugInfo() || LScopes.empty()) {
1555 // If we don't have a lexical scope for this function then there will
1556 // be a hole in the range information. Keep note of this by setting the
1557 // previously used section to nullptr.
1558 PrevSection = nullptr;
1564 // Define end label for subprogram.
1565 FunctionEndSym = Asm->GetTempSymbol("func_end", Asm->getFunctionNumber());
1566 // Assumes in correct section after the entry point.
1567 Asm->OutStreamer.EmitLabel(FunctionEndSym);
1569 // Set DwarfDwarfCompileUnitID in MCContext to default value.
1570 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1572 SmallPtrSet<const MDNode *, 16> ProcessedVars;
1573 collectVariableInfo(ProcessedVars);
1575 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1576 DwarfCompileUnit &TheCU = *SPMap.lookup(FnScope->getScopeNode());
1578 // Construct abstract scopes.
1579 for (LexicalScope *AScope : LScopes.getAbstractScopesList()) {
1580 DISubprogram SP(AScope->getScopeNode());
1581 if (SP.isSubprogram()) {
1582 // Collect info for variables that were optimized out.
1583 DIArray Variables = SP.getVariables();
1584 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1585 DIVariable DV(Variables.getElement(i));
1586 if (!DV || !DV.isVariable() || !ProcessedVars.insert(DV))
1588 // Check that DbgVariable for DV wasn't created earlier, when
1589 // findAbstractVariable() was called for inlined instance of DV.
1590 LLVMContext &Ctx = DV->getContext();
1591 DIVariable CleanDV = cleanseInlinedVariable(DV, Ctx);
1592 if (AbstractVariables.lookup(CleanDV))
1594 if (LexicalScope *Scope = LScopes.findAbstractScope(DV.getContext()))
1595 addScopeVariable(Scope, new DbgVariable(DV, nullptr, this));
1598 if (ProcessedSPNodes.count(AScope->getScopeNode()) == 0)
1599 constructAbstractSubprogramScopeDIE(TheCU, AScope);
1602 DIE &CurFnDIE = constructSubprogramScopeDIE(TheCU, FnScope);
1603 if (!CurFn->getTarget().Options.DisableFramePointerElim(*CurFn))
1604 TheCU.addFlag(CurFnDIE, dwarf::DW_AT_APPLE_omit_frame_ptr);
1606 // Add the range of this function to the list of ranges for the CU.
1607 RangeSpan Span(FunctionBeginSym, FunctionEndSym);
1608 TheCU.addRange(std::move(Span));
1609 PrevSection = Asm->getCurrentSection();
1613 for (auto &I : ScopeVariables)
1614 DeleteContainerPointers(I.second);
1615 ScopeVariables.clear();
1616 DeleteContainerPointers(CurrentFnArguments);
1617 UserVariables.clear();
1619 AbstractVariables.clear();
1620 LabelsBeforeInsn.clear();
1621 LabelsAfterInsn.clear();
1622 PrevLabel = nullptr;
1626 // Register a source line with debug info. Returns the unique label that was
1627 // emitted and which provides correspondence to the source line list.
1628 void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S,
1633 unsigned Discriminator = 0;
1635 DIDescriptor Scope(S);
1637 if (Scope.isCompileUnit()) {
1638 DICompileUnit CU(S);
1639 Fn = CU.getFilename();
1640 Dir = CU.getDirectory();
1641 } else if (Scope.isFile()) {
1643 Fn = F.getFilename();
1644 Dir = F.getDirectory();
1645 } else if (Scope.isSubprogram()) {
1647 Fn = SP.getFilename();
1648 Dir = SP.getDirectory();
1649 } else if (Scope.isLexicalBlockFile()) {
1650 DILexicalBlockFile DBF(S);
1651 Fn = DBF.getFilename();
1652 Dir = DBF.getDirectory();
1653 } else if (Scope.isLexicalBlock()) {
1654 DILexicalBlock DB(S);
1655 Fn = DB.getFilename();
1656 Dir = DB.getDirectory();
1657 Discriminator = DB.getDiscriminator();
1659 llvm_unreachable("Unexpected scope info");
1661 unsigned CUID = Asm->OutStreamer.getContext().getDwarfCompileUnitID();
1662 Src = static_cast<DwarfCompileUnit &>(*InfoHolder.getUnits()[CUID])
1663 .getOrCreateSourceID(Fn, Dir);
1665 Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0,
1669 //===----------------------------------------------------------------------===//
1671 //===----------------------------------------------------------------------===//
1673 // Emit initial Dwarf sections with a label at the start of each one.
1674 void DwarfDebug::emitSectionLabels() {
1675 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
1677 // Dwarf sections base addresses.
1678 DwarfInfoSectionSym =
1679 emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info");
1680 if (useSplitDwarf())
1681 DwarfInfoDWOSectionSym =
1682 emitSectionSym(Asm, TLOF.getDwarfInfoDWOSection(), "section_info_dwo");
1683 DwarfAbbrevSectionSym =
1684 emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev");
1685 if (useSplitDwarf())
1686 DwarfAbbrevDWOSectionSym = emitSectionSym(
1687 Asm, TLOF.getDwarfAbbrevDWOSection(), "section_abbrev_dwo");
1688 if (GenerateARangeSection)
1689 emitSectionSym(Asm, TLOF.getDwarfARangesSection());
1691 DwarfLineSectionSym =
1692 emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line");
1693 if (GenerateGnuPubSections) {
1694 DwarfGnuPubNamesSectionSym =
1695 emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection());
1696 DwarfGnuPubTypesSectionSym =
1697 emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection());
1698 } else if (HasDwarfPubSections) {
1699 emitSectionSym(Asm, TLOF.getDwarfPubNamesSection());
1700 emitSectionSym(Asm, TLOF.getDwarfPubTypesSection());
1703 DwarfStrSectionSym =
1704 emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string");
1705 if (useSplitDwarf()) {
1706 DwarfStrDWOSectionSym =
1707 emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string");
1708 DwarfAddrSectionSym =
1709 emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec");
1710 DwarfDebugLocSectionSym =
1711 emitSectionSym(Asm, TLOF.getDwarfLocDWOSection(), "skel_loc");
1713 DwarfDebugLocSectionSym =
1714 emitSectionSym(Asm, TLOF.getDwarfLocSection(), "section_debug_loc");
1715 DwarfDebugRangeSectionSym =
1716 emitSectionSym(Asm, TLOF.getDwarfRangesSection(), "debug_range");
1719 // Recursively emits a debug information entry.
1720 void DwarfDebug::emitDIE(DIE &Die) {
1721 // Get the abbreviation for this DIE.
1722 const DIEAbbrev &Abbrev = Die.getAbbrev();
1724 // Emit the code (index) for the abbreviation.
1725 if (Asm->isVerbose())
1726 Asm->OutStreamer.AddComment("Abbrev [" + Twine(Abbrev.getNumber()) +
1727 "] 0x" + Twine::utohexstr(Die.getOffset()) +
1728 ":0x" + Twine::utohexstr(Die.getSize()) + " " +
1729 dwarf::TagString(Abbrev.getTag()));
1730 Asm->EmitULEB128(Abbrev.getNumber());
1732 const SmallVectorImpl<DIEValue *> &Values = Die.getValues();
1733 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
1735 // Emit the DIE attribute values.
1736 for (unsigned i = 0, N = Values.size(); i < N; ++i) {
1737 dwarf::Attribute Attr = AbbrevData[i].getAttribute();
1738 dwarf::Form Form = AbbrevData[i].getForm();
1739 assert(Form && "Too many attributes for DIE (check abbreviation)");
1741 if (Asm->isVerbose()) {
1742 Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr));
1743 if (Attr == dwarf::DW_AT_accessibility)
1744 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(
1745 cast<DIEInteger>(Values[i])->getValue()));
1748 // Emit an attribute using the defined form.
1749 Values[i]->EmitValue(Asm, Form);
1752 // Emit the DIE children if any.
1753 if (Abbrev.hasChildren()) {
1754 for (auto &Child : Die.getChildren())
1757 Asm->OutStreamer.AddComment("End Of Children Mark");
1762 // Emit the debug info section.
1763 void DwarfDebug::emitDebugInfo() {
1764 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1766 Holder.emitUnits(this, DwarfAbbrevSectionSym);
1769 // Emit the abbreviation section.
1770 void DwarfDebug::emitAbbreviations() {
1771 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1773 Holder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection());
1776 // Emit the last address of the section and the end of the line matrix.
1777 void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) {
1778 // Define last address of section.
1779 Asm->OutStreamer.AddComment("Extended Op");
1782 Asm->OutStreamer.AddComment("Op size");
1783 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1);
1784 Asm->OutStreamer.AddComment("DW_LNE_set_address");
1785 Asm->EmitInt8(dwarf::DW_LNE_set_address);
1787 Asm->OutStreamer.AddComment("Section end label");
1789 Asm->OutStreamer.EmitSymbolValue(
1790 Asm->GetTempSymbol("section_end", SectionEnd),
1791 Asm->getDataLayout().getPointerSize());
1793 // Mark end of matrix.
1794 Asm->OutStreamer.AddComment("DW_LNE_end_sequence");
1800 // Emit visible names into a hashed accelerator table section.
1801 void DwarfDebug::emitAccelNames() {
1802 AccelNames.FinalizeTable(Asm, "Names");
1803 Asm->OutStreamer.SwitchSection(
1804 Asm->getObjFileLowering().getDwarfAccelNamesSection());
1805 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin");
1806 Asm->OutStreamer.EmitLabel(SectionBegin);
1808 // Emit the full data.
1809 AccelNames.Emit(Asm, SectionBegin, &InfoHolder);
1812 // Emit objective C classes and categories into a hashed accelerator table
1814 void DwarfDebug::emitAccelObjC() {
1815 AccelObjC.FinalizeTable(Asm, "ObjC");
1816 Asm->OutStreamer.SwitchSection(
1817 Asm->getObjFileLowering().getDwarfAccelObjCSection());
1818 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin");
1819 Asm->OutStreamer.EmitLabel(SectionBegin);
1821 // Emit the full data.
1822 AccelObjC.Emit(Asm, SectionBegin, &InfoHolder);
1825 // Emit namespace dies into a hashed accelerator table.
1826 void DwarfDebug::emitAccelNamespaces() {
1827 AccelNamespace.FinalizeTable(Asm, "namespac");
1828 Asm->OutStreamer.SwitchSection(
1829 Asm->getObjFileLowering().getDwarfAccelNamespaceSection());
1830 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin");
1831 Asm->OutStreamer.EmitLabel(SectionBegin);
1833 // Emit the full data.
1834 AccelNamespace.Emit(Asm, SectionBegin, &InfoHolder);
1837 // Emit type dies into a hashed accelerator table.
1838 void DwarfDebug::emitAccelTypes() {
1840 AccelTypes.FinalizeTable(Asm, "types");
1841 Asm->OutStreamer.SwitchSection(
1842 Asm->getObjFileLowering().getDwarfAccelTypesSection());
1843 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin");
1844 Asm->OutStreamer.EmitLabel(SectionBegin);
1846 // Emit the full data.
1847 AccelTypes.Emit(Asm, SectionBegin, &InfoHolder);
1850 // Public name handling.
1851 // The format for the various pubnames:
1853 // dwarf pubnames - offset/name pairs where the offset is the offset into the CU
1854 // for the DIE that is named.
1856 // gnu pubnames - offset/index value/name tuples where the offset is the offset
1857 // into the CU and the index value is computed according to the type of value
1858 // for the DIE that is named.
1860 // For type units the offset is the offset of the skeleton DIE. For split dwarf
1861 // it's the offset within the debug_info/debug_types dwo section, however, the
1862 // reference in the pubname header doesn't change.
1864 /// computeIndexValue - Compute the gdb index value for the DIE and CU.
1865 static dwarf::PubIndexEntryDescriptor computeIndexValue(DwarfUnit *CU,
1867 dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC;
1869 // We could have a specification DIE that has our most of our knowledge,
1870 // look for that now.
1871 DIEValue *SpecVal = Die->findAttribute(dwarf::DW_AT_specification);
1873 DIE &SpecDIE = cast<DIEEntry>(SpecVal)->getEntry();
1874 if (SpecDIE.findAttribute(dwarf::DW_AT_external))
1875 Linkage = dwarf::GIEL_EXTERNAL;
1876 } else if (Die->findAttribute(dwarf::DW_AT_external))
1877 Linkage = dwarf::GIEL_EXTERNAL;
1879 switch (Die->getTag()) {
1880 case dwarf::DW_TAG_class_type:
1881 case dwarf::DW_TAG_structure_type:
1882 case dwarf::DW_TAG_union_type:
1883 case dwarf::DW_TAG_enumeration_type:
1884 return dwarf::PubIndexEntryDescriptor(
1885 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus
1886 ? dwarf::GIEL_STATIC
1887 : dwarf::GIEL_EXTERNAL);
1888 case dwarf::DW_TAG_typedef:
1889 case dwarf::DW_TAG_base_type:
1890 case dwarf::DW_TAG_subrange_type:
1891 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC);
1892 case dwarf::DW_TAG_namespace:
1893 return dwarf::GIEK_TYPE;
1894 case dwarf::DW_TAG_subprogram:
1895 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage);
1896 case dwarf::DW_TAG_constant:
1897 case dwarf::DW_TAG_variable:
1898 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage);
1899 case dwarf::DW_TAG_enumerator:
1900 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE,
1901 dwarf::GIEL_STATIC);
1903 return dwarf::GIEK_NONE;
1907 /// emitDebugPubNames - Emit visible names into a debug pubnames section.
1909 void DwarfDebug::emitDebugPubNames(bool GnuStyle) {
1910 const MCSection *PSec =
1911 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection()
1912 : Asm->getObjFileLowering().getDwarfPubNamesSection();
1914 emitDebugPubSection(GnuStyle, PSec, "Names", &DwarfUnit::getGlobalNames);
1917 void DwarfDebug::emitDebugPubSection(
1918 bool GnuStyle, const MCSection *PSec, StringRef Name,
1919 const StringMap<const DIE *> &(DwarfUnit::*Accessor)() const) {
1920 for (const auto &NU : CUMap) {
1921 DwarfCompileUnit *TheU = NU.second;
1923 const auto &Globals = (TheU->*Accessor)();
1925 if (Globals.empty())
1928 if (auto Skeleton = static_cast<DwarfCompileUnit *>(TheU->getSkeleton()))
1930 unsigned ID = TheU->getUniqueID();
1932 // Start the dwarf pubnames section.
1933 Asm->OutStreamer.SwitchSection(PSec);
1936 Asm->OutStreamer.AddComment("Length of Public " + Name + " Info");
1937 MCSymbol *BeginLabel = Asm->GetTempSymbol("pub" + Name + "_begin", ID);
1938 MCSymbol *EndLabel = Asm->GetTempSymbol("pub" + Name + "_end", ID);
1939 Asm->EmitLabelDifference(EndLabel, BeginLabel, 4);
1941 Asm->OutStreamer.EmitLabel(BeginLabel);
1943 Asm->OutStreamer.AddComment("DWARF Version");
1944 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION);
1946 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info");
1947 Asm->EmitSectionOffset(TheU->getLabelBegin(), TheU->getSectionSym());
1949 Asm->OutStreamer.AddComment("Compilation Unit Length");
1950 Asm->EmitLabelDifference(TheU->getLabelEnd(), TheU->getLabelBegin(), 4);
1952 // Emit the pubnames for this compilation unit.
1953 for (const auto &GI : Globals) {
1954 const char *Name = GI.getKeyData();
1955 const DIE *Entity = GI.second;
1957 Asm->OutStreamer.AddComment("DIE offset");
1958 Asm->EmitInt32(Entity->getOffset());
1961 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheU, Entity);
1962 Asm->OutStreamer.AddComment(
1963 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " +
1964 dwarf::GDBIndexEntryLinkageString(Desc.Linkage));
1965 Asm->EmitInt8(Desc.toBits());
1968 Asm->OutStreamer.AddComment("External Name");
1969 Asm->OutStreamer.EmitBytes(StringRef(Name, GI.getKeyLength() + 1));
1972 Asm->OutStreamer.AddComment("End Mark");
1974 Asm->OutStreamer.EmitLabel(EndLabel);
1978 void DwarfDebug::emitDebugPubTypes(bool GnuStyle) {
1979 const MCSection *PSec =
1980 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection()
1981 : Asm->getObjFileLowering().getDwarfPubTypesSection();
1983 emitDebugPubSection(GnuStyle, PSec, "Types", &DwarfUnit::getGlobalTypes);
1986 // Emit visible names into a debug str section.
1987 void DwarfDebug::emitDebugStr() {
1988 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1989 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection());
1992 void DwarfDebug::emitDebugLocEntry(ByteStreamer &Streamer,
1993 const DebugLocEntry &Entry) {
1994 assert(Entry.getValues().size() == 1 &&
1995 "multi-value entries are not supported yet.");
1996 const DebugLocEntry::Value Value = Entry.getValues()[0];
1997 DIVariable DV(Value.getVariable());
1998 if (Value.isInt()) {
1999 DIBasicType BTy(resolve(DV.getType()));
2000 if (BTy.Verify() && (BTy.getEncoding() == dwarf::DW_ATE_signed ||
2001 BTy.getEncoding() == dwarf::DW_ATE_signed_char)) {
2002 Streamer.EmitInt8(dwarf::DW_OP_consts, "DW_OP_consts");
2003 Streamer.EmitSLEB128(Value.getInt());
2005 Streamer.EmitInt8(dwarf::DW_OP_constu, "DW_OP_constu");
2006 Streamer.EmitULEB128(Value.getInt());
2008 } else if (Value.isLocation()) {
2009 MachineLocation Loc = Value.getLoc();
2010 if (!DV.hasComplexAddress())
2012 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2014 // Complex address entry.
2015 unsigned N = DV.getNumAddrElements();
2017 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) {
2018 if (Loc.getOffset()) {
2020 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2021 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
2022 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
2023 Streamer.EmitSLEB128(DV.getAddrElement(1));
2025 // If first address element is OpPlus then emit
2026 // DW_OP_breg + Offset instead of DW_OP_reg + Offset.
2027 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1));
2028 Asm->EmitDwarfRegOp(Streamer, TLoc, DV.isIndirect());
2032 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2035 // Emit remaining complex address elements.
2036 for (; i < N; ++i) {
2037 uint64_t Element = DV.getAddrElement(i);
2038 if (Element == DIBuilder::OpPlus) {
2039 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
2040 Streamer.EmitULEB128(DV.getAddrElement(++i));
2041 } else if (Element == DIBuilder::OpDeref) {
2043 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
2045 llvm_unreachable("unknown Opcode found in complex address");
2049 // else ... ignore constant fp. There is not any good way to
2050 // to represent them here in dwarf.
2054 void DwarfDebug::emitDebugLocEntryLocation(const DebugLocEntry &Entry) {
2055 Asm->OutStreamer.AddComment("Loc expr size");
2056 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol();
2057 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol();
2058 Asm->EmitLabelDifference(end, begin, 2);
2059 Asm->OutStreamer.EmitLabel(begin);
2061 APByteStreamer Streamer(*Asm);
2062 emitDebugLocEntry(Streamer, Entry);
2064 Asm->OutStreamer.EmitLabel(end);
2067 // Emit locations into the debug loc section.
2068 void DwarfDebug::emitDebugLoc() {
2069 // Start the dwarf loc section.
2070 Asm->OutStreamer.SwitchSection(
2071 Asm->getObjFileLowering().getDwarfLocSection());
2072 unsigned char Size = Asm->getDataLayout().getPointerSize();
2073 for (const auto &DebugLoc : DotDebugLocEntries) {
2074 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2075 for (const auto &Entry : DebugLoc.List) {
2076 // Set up the range. This range is relative to the entry point of the
2077 // compile unit. This is a hard coded 0 for low_pc when we're emitting
2078 // ranges, or the DW_AT_low_pc on the compile unit otherwise.
2079 const DwarfCompileUnit *CU = Entry.getCU();
2080 if (CU->getRanges().size() == 1) {
2081 // Grab the begin symbol from the first range as our base.
2082 const MCSymbol *Base = CU->getRanges()[0].getStart();
2083 Asm->EmitLabelDifference(Entry.getBeginSym(), Base, Size);
2084 Asm->EmitLabelDifference(Entry.getEndSym(), Base, Size);
2086 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size);
2087 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size);
2090 emitDebugLocEntryLocation(Entry);
2092 Asm->OutStreamer.EmitIntValue(0, Size);
2093 Asm->OutStreamer.EmitIntValue(0, Size);
2097 void DwarfDebug::emitDebugLocDWO() {
2098 Asm->OutStreamer.SwitchSection(
2099 Asm->getObjFileLowering().getDwarfLocDWOSection());
2100 for (const auto &DebugLoc : DotDebugLocEntries) {
2101 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2102 for (const auto &Entry : DebugLoc.List) {
2103 // Just always use start_length for now - at least that's one address
2104 // rather than two. We could get fancier and try to, say, reuse an
2105 // address we know we've emitted elsewhere (the start of the function?
2106 // The start of the CU or CU subrange that encloses this range?)
2107 Asm->EmitInt8(dwarf::DW_LLE_start_length_entry);
2108 unsigned idx = AddrPool.getIndex(Entry.getBeginSym());
2109 Asm->EmitULEB128(idx);
2110 Asm->EmitLabelDifference(Entry.getEndSym(), Entry.getBeginSym(), 4);
2112 emitDebugLocEntryLocation(Entry);
2114 Asm->EmitInt8(dwarf::DW_LLE_end_of_list_entry);
2119 const MCSymbol *Start, *End;
2122 // Emit a debug aranges section, containing a CU lookup for any
2123 // address we can tie back to a CU.
2124 void DwarfDebug::emitDebugARanges() {
2125 // Start the dwarf aranges section.
2126 Asm->OutStreamer.SwitchSection(
2127 Asm->getObjFileLowering().getDwarfARangesSection());
2129 typedef DenseMap<DwarfCompileUnit *, std::vector<ArangeSpan>> SpansType;
2133 // Build a list of sections used.
2134 std::vector<const MCSection *> Sections;
2135 for (const auto &it : SectionMap) {
2136 const MCSection *Section = it.first;
2137 Sections.push_back(Section);
2140 // Sort the sections into order.
2141 // This is only done to ensure consistent output order across different runs.
2142 std::sort(Sections.begin(), Sections.end(), SectionSort);
2144 // Build a set of address spans, sorted by CU.
2145 for (const MCSection *Section : Sections) {
2146 SmallVector<SymbolCU, 8> &List = SectionMap[Section];
2147 if (List.size() < 2)
2150 // Sort the symbols by offset within the section.
2151 std::sort(List.begin(), List.end(),
2152 [&](const SymbolCU &A, const SymbolCU &B) {
2153 unsigned IA = A.Sym ? Asm->OutStreamer.GetSymbolOrder(A.Sym) : 0;
2154 unsigned IB = B.Sym ? Asm->OutStreamer.GetSymbolOrder(B.Sym) : 0;
2156 // Symbols with no order assigned should be placed at the end.
2157 // (e.g. section end labels)
2165 // If we have no section (e.g. common), just write out
2166 // individual spans for each symbol.
2168 for (const SymbolCU &Cur : List) {
2170 Span.Start = Cur.Sym;
2173 Spans[Cur.CU].push_back(Span);
2176 // Build spans between each label.
2177 const MCSymbol *StartSym = List[0].Sym;
2178 for (size_t n = 1, e = List.size(); n < e; n++) {
2179 const SymbolCU &Prev = List[n - 1];
2180 const SymbolCU &Cur = List[n];
2182 // Try and build the longest span we can within the same CU.
2183 if (Cur.CU != Prev.CU) {
2185 Span.Start = StartSym;
2187 Spans[Prev.CU].push_back(Span);
2194 unsigned PtrSize = Asm->getDataLayout().getPointerSize();
2196 // Build a list of CUs used.
2197 std::vector<DwarfCompileUnit *> CUs;
2198 for (const auto &it : Spans) {
2199 DwarfCompileUnit *CU = it.first;
2203 // Sort the CU list (again, to ensure consistent output order).
2204 std::sort(CUs.begin(), CUs.end(), [](const DwarfUnit *A, const DwarfUnit *B) {
2205 return A->getUniqueID() < B->getUniqueID();
2208 // Emit an arange table for each CU we used.
2209 for (DwarfCompileUnit *CU : CUs) {
2210 std::vector<ArangeSpan> &List = Spans[CU];
2212 // Emit size of content not including length itself.
2213 unsigned ContentSize =
2214 sizeof(int16_t) + // DWARF ARange version number
2215 sizeof(int32_t) + // Offset of CU in the .debug_info section
2216 sizeof(int8_t) + // Pointer Size (in bytes)
2217 sizeof(int8_t); // Segment Size (in bytes)
2219 unsigned TupleSize = PtrSize * 2;
2221 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple.
2223 OffsetToAlignment(sizeof(int32_t) + ContentSize, TupleSize);
2225 ContentSize += Padding;
2226 ContentSize += (List.size() + 1) * TupleSize;
2228 // For each compile unit, write the list of spans it covers.
2229 Asm->OutStreamer.AddComment("Length of ARange Set");
2230 Asm->EmitInt32(ContentSize);
2231 Asm->OutStreamer.AddComment("DWARF Arange version number");
2232 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION);
2233 Asm->OutStreamer.AddComment("Offset Into Debug Info Section");
2234 Asm->EmitSectionOffset(CU->getLocalLabelBegin(), CU->getLocalSectionSym());
2235 Asm->OutStreamer.AddComment("Address Size (in bytes)");
2236 Asm->EmitInt8(PtrSize);
2237 Asm->OutStreamer.AddComment("Segment Size (in bytes)");
2240 Asm->OutStreamer.EmitFill(Padding, 0xff);
2242 for (const ArangeSpan &Span : List) {
2243 Asm->EmitLabelReference(Span.Start, PtrSize);
2245 // Calculate the size as being from the span start to it's end.
2247 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize);
2249 // For symbols without an end marker (e.g. common), we
2250 // write a single arange entry containing just that one symbol.
2251 uint64_t Size = SymSize[Span.Start];
2255 Asm->OutStreamer.EmitIntValue(Size, PtrSize);
2259 Asm->OutStreamer.AddComment("ARange terminator");
2260 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2261 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2265 // Emit visible names into a debug ranges section.
2266 void DwarfDebug::emitDebugRanges() {
2267 // Start the dwarf ranges section.
2268 Asm->OutStreamer.SwitchSection(
2269 Asm->getObjFileLowering().getDwarfRangesSection());
2271 // Size for our labels.
2272 unsigned char Size = Asm->getDataLayout().getPointerSize();
2274 // Grab the specific ranges for the compile units in the module.
2275 for (const auto &I : CUMap) {
2276 DwarfCompileUnit *TheCU = I.second;
2278 // Iterate over the misc ranges for the compile units in the module.
2279 for (const RangeSpanList &List : TheCU->getRangeLists()) {
2280 // Emit our symbol so we can find the beginning of the range.
2281 Asm->OutStreamer.EmitLabel(List.getSym());
2283 for (const RangeSpan &Range : List.getRanges()) {
2284 const MCSymbol *Begin = Range.getStart();
2285 const MCSymbol *End = Range.getEnd();
2286 assert(Begin && "Range without a begin symbol?");
2287 assert(End && "Range without an end symbol?");
2288 if (TheCU->getRanges().size() == 1) {
2289 // Grab the begin symbol from the first range as our base.
2290 const MCSymbol *Base = TheCU->getRanges()[0].getStart();
2291 Asm->EmitLabelDifference(Begin, Base, Size);
2292 Asm->EmitLabelDifference(End, Base, Size);
2294 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2295 Asm->OutStreamer.EmitSymbolValue(End, Size);
2299 // And terminate the list with two 0 values.
2300 Asm->OutStreamer.EmitIntValue(0, Size);
2301 Asm->OutStreamer.EmitIntValue(0, Size);
2304 // Now emit a range for the CU itself.
2305 if (TheCU->getRanges().size() > 1) {
2306 Asm->OutStreamer.EmitLabel(
2307 Asm->GetTempSymbol("cu_ranges", TheCU->getUniqueID()));
2308 for (const RangeSpan &Range : TheCU->getRanges()) {
2309 const MCSymbol *Begin = Range.getStart();
2310 const MCSymbol *End = Range.getEnd();
2311 assert(Begin && "Range without a begin symbol?");
2312 assert(End && "Range without an end symbol?");
2313 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2314 Asm->OutStreamer.EmitSymbolValue(End, Size);
2316 // And terminate the list with two 0 values.
2317 Asm->OutStreamer.EmitIntValue(0, Size);
2318 Asm->OutStreamer.EmitIntValue(0, Size);
2323 // DWARF5 Experimental Separate Dwarf emitters.
2325 void DwarfDebug::initSkeletonUnit(const DwarfUnit &U, DIE &Die,
2326 std::unique_ptr<DwarfUnit> NewU) {
2327 NewU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name,
2328 U.getCUNode().getSplitDebugFilename());
2330 if (!CompilationDir.empty())
2331 NewU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
2333 addGnuPubAttributes(*NewU, Die);
2335 SkeletonHolder.addUnit(std::move(NewU));
2338 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list,
2339 // DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id,
2340 // DW_AT_addr_base, DW_AT_ranges_base.
2341 DwarfCompileUnit &DwarfDebug::constructSkeletonCU(const DwarfCompileUnit &CU) {
2343 auto OwnedUnit = make_unique<DwarfCompileUnit>(
2344 CU.getUniqueID(), CU.getCUNode(), Asm, this, &SkeletonHolder);
2345 DwarfCompileUnit &NewCU = *OwnedUnit;
2346 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
2347 DwarfInfoSectionSym);
2349 NewCU.initStmtList(DwarfLineSectionSym);
2351 initSkeletonUnit(CU, NewCU.getUnitDie(), std::move(OwnedUnit));
2356 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_dwo_name,
2358 DwarfTypeUnit &DwarfDebug::constructSkeletonTU(DwarfTypeUnit &TU) {
2359 DwarfCompileUnit &CU = static_cast<DwarfCompileUnit &>(
2360 *SkeletonHolder.getUnits()[TU.getCU().getUniqueID()]);
2362 auto OwnedUnit = make_unique<DwarfTypeUnit>(TU.getUniqueID(), CU, Asm, this,
2364 DwarfTypeUnit &NewTU = *OwnedUnit;
2365 NewTU.setTypeSignature(TU.getTypeSignature());
2366 NewTU.setType(nullptr);
2368 Asm->getObjFileLowering().getDwarfTypesSection(TU.getTypeSignature()));
2370 initSkeletonUnit(TU, NewTU.getUnitDie(), std::move(OwnedUnit));
2374 // Emit the .debug_info.dwo section for separated dwarf. This contains the
2375 // compile units that would normally be in debug_info.
2376 void DwarfDebug::emitDebugInfoDWO() {
2377 assert(useSplitDwarf() && "No split dwarf debug info?");
2378 // Don't pass an abbrev symbol, using a constant zero instead so as not to
2379 // emit relocations into the dwo file.
2380 InfoHolder.emitUnits(this, /* AbbrevSymbol */ nullptr);
2383 // Emit the .debug_abbrev.dwo section for separated dwarf. This contains the
2384 // abbreviations for the .debug_info.dwo section.
2385 void DwarfDebug::emitDebugAbbrevDWO() {
2386 assert(useSplitDwarf() && "No split dwarf?");
2387 InfoHolder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection());
2390 void DwarfDebug::emitDebugLineDWO() {
2391 assert(useSplitDwarf() && "No split dwarf?");
2392 Asm->OutStreamer.SwitchSection(
2393 Asm->getObjFileLowering().getDwarfLineDWOSection());
2394 SplitTypeUnitFileTable.Emit(Asm->OutStreamer);
2397 // Emit the .debug_str.dwo section for separated dwarf. This contains the
2398 // string section and is identical in format to traditional .debug_str
2400 void DwarfDebug::emitDebugStrDWO() {
2401 assert(useSplitDwarf() && "No split dwarf?");
2402 const MCSection *OffSec =
2403 Asm->getObjFileLowering().getDwarfStrOffDWOSection();
2404 const MCSymbol *StrSym = DwarfStrSectionSym;
2405 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(),
2409 MCDwarfDwoLineTable *DwarfDebug::getDwoLineTable(const DwarfCompileUnit &CU) {
2410 if (!useSplitDwarf())
2413 SplitTypeUnitFileTable.setCompilationDir(CU.getCUNode().getDirectory());
2414 return &SplitTypeUnitFileTable;
2417 static uint64_t makeTypeSignature(StringRef Identifier) {
2419 Hash.update(Identifier);
2420 // ... take the least significant 8 bytes and return those. Our MD5
2421 // implementation always returns its results in little endian, swap bytes
2423 MD5::MD5Result Result;
2425 return *reinterpret_cast<support::ulittle64_t *>(Result + 8);
2428 void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU,
2429 StringRef Identifier, DIE &RefDie,
2430 DICompositeType CTy) {
2431 // Fast path if we're building some type units and one has already used the
2432 // address pool we know we're going to throw away all this work anyway, so
2433 // don't bother building dependent types.
2434 if (!TypeUnitsUnderConstruction.empty() && AddrPool.hasBeenUsed())
2437 const DwarfTypeUnit *&TU = DwarfTypeUnits[CTy];
2439 CU.addDIETypeSignature(RefDie, *TU);
2443 bool TopLevelType = TypeUnitsUnderConstruction.empty();
2444 AddrPool.resetUsedFlag();
2447 make_unique<DwarfTypeUnit>(InfoHolder.getUnits().size(), CU, Asm, this,
2448 &InfoHolder, getDwoLineTable(CU));
2449 DwarfTypeUnit &NewTU = *OwnedUnit;
2450 DIE &UnitDie = NewTU.getUnitDie();
2452 TypeUnitsUnderConstruction.push_back(
2453 std::make_pair(std::move(OwnedUnit), CTy));
2455 NewTU.addUInt(UnitDie, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
2458 uint64_t Signature = makeTypeSignature(Identifier);
2459 NewTU.setTypeSignature(Signature);
2461 if (!useSplitDwarf())
2462 CU.applyStmtList(UnitDie);
2466 ? Asm->getObjFileLowering().getDwarfTypesDWOSection(Signature)
2467 : Asm->getObjFileLowering().getDwarfTypesSection(Signature));
2469 NewTU.setType(NewTU.createTypeDIE(CTy));
2472 auto TypeUnitsToAdd = std::move(TypeUnitsUnderConstruction);
2473 TypeUnitsUnderConstruction.clear();
2475 // Types referencing entries in the address table cannot be placed in type
2477 if (AddrPool.hasBeenUsed()) {
2479 // Remove all the types built while building this type.
2480 // This is pessimistic as some of these types might not be dependent on
2481 // the type that used an address.
2482 for (const auto &TU : TypeUnitsToAdd)
2483 DwarfTypeUnits.erase(TU.second);
2485 // Construct this type in the CU directly.
2486 // This is inefficient because all the dependent types will be rebuilt
2487 // from scratch, including building them in type units, discovering that
2488 // they depend on addresses, throwing them out and rebuilding them.
2489 CU.constructTypeDIE(RefDie, CTy);
2493 // If the type wasn't dependent on fission addresses, finish adding the type
2494 // and all its dependent types.
2495 for (auto &TU : TypeUnitsToAdd) {
2496 if (useSplitDwarf())
2497 TU.first->setSkeleton(constructSkeletonTU(*TU.first));
2498 InfoHolder.addUnit(std::move(TU.first));
2501 CU.addDIETypeSignature(RefDie, NewTU);
2504 void DwarfDebug::attachLowHighPC(DwarfCompileUnit &Unit, DIE &D,
2505 MCSymbol *Begin, MCSymbol *End) {
2506 Unit.addLabelAddress(D, dwarf::DW_AT_low_pc, Begin);
2507 if (DwarfVersion < 4)
2508 Unit.addLabelAddress(D, dwarf::DW_AT_high_pc, End);
2510 Unit.addLabelDelta(D, dwarf::DW_AT_high_pc, End, Begin);
2513 // Accelerator table mutators - add each name along with its companion
2514 // DIE to the proper table while ensuring that the name that we're going
2515 // to reference is in the string table. We do this since the names we
2516 // add may not only be identical to the names in the DIE.
2517 void DwarfDebug::addAccelName(StringRef Name, const DIE &Die) {
2518 if (!useDwarfAccelTables())
2520 AccelNames.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2524 void DwarfDebug::addAccelObjC(StringRef Name, const DIE &Die) {
2525 if (!useDwarfAccelTables())
2527 AccelObjC.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2531 void DwarfDebug::addAccelNamespace(StringRef Name, const DIE &Die) {
2532 if (!useDwarfAccelTables())
2534 AccelNamespace.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2538 void DwarfDebug::addAccelType(StringRef Name, const DIE &Die, char Flags) {
2539 if (!useDwarfAccelTables())
2541 AccelTypes.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),