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/Endian.h"
40 #include "llvm/Support/ErrorHandling.h"
41 #include "llvm/Support/FormattedStream.h"
42 #include "llvm/Support/LEB128.h"
43 #include "llvm/Support/MD5.h"
44 #include "llvm/Support/Path.h"
45 #include "llvm/Support/Timer.h"
46 #include "llvm/Target/TargetFrameLowering.h"
47 #include "llvm/Target/TargetLoweringObjectFile.h"
48 #include "llvm/Target/TargetMachine.h"
49 #include "llvm/Target/TargetOptions.h"
50 #include "llvm/Target/TargetRegisterInfo.h"
53 #define DEBUG_TYPE "dwarfdebug"
56 DisableDebugInfoPrinting("disable-debug-info-print", cl::Hidden,
57 cl::desc("Disable debug info printing"));
59 static cl::opt<bool> UnknownLocations(
60 "use-unknown-locations", cl::Hidden,
61 cl::desc("Make an absence of debug location information explicit."),
65 GenerateGnuPubSections("generate-gnu-dwarf-pub-sections", cl::Hidden,
66 cl::desc("Generate GNU-style pubnames and pubtypes"),
69 static cl::opt<bool> GenerateARangeSection("generate-arange-section",
71 cl::desc("Generate dwarf aranges"),
75 enum DefaultOnOff { Default, Enable, Disable };
78 static cl::opt<DefaultOnOff>
79 DwarfAccelTables("dwarf-accel-tables", cl::Hidden,
80 cl::desc("Output prototype dwarf accelerator tables."),
81 cl::values(clEnumVal(Default, "Default for platform"),
82 clEnumVal(Enable, "Enabled"),
83 clEnumVal(Disable, "Disabled"), clEnumValEnd),
86 static cl::opt<DefaultOnOff>
87 SplitDwarf("split-dwarf", cl::Hidden,
88 cl::desc("Output DWARF5 split debug info."),
89 cl::values(clEnumVal(Default, "Default for platform"),
90 clEnumVal(Enable, "Enabled"),
91 clEnumVal(Disable, "Disabled"), clEnumValEnd),
94 static cl::opt<DefaultOnOff>
95 DwarfPubSections("generate-dwarf-pub-sections", cl::Hidden,
96 cl::desc("Generate DWARF pubnames and pubtypes sections"),
97 cl::values(clEnumVal(Default, "Default for platform"),
98 clEnumVal(Enable, "Enabled"),
99 clEnumVal(Disable, "Disabled"), clEnumValEnd),
102 static const char *const DWARFGroupName = "DWARF Emission";
103 static const char *const DbgTimerName = "DWARF Debug Writer";
105 //===----------------------------------------------------------------------===//
107 /// resolve - Look in the DwarfDebug map for the MDNode that
108 /// corresponds to the reference.
109 template <typename T> T DbgVariable::resolve(DIRef<T> Ref) const {
110 return DD->resolve(Ref);
113 bool DbgVariable::isBlockByrefVariable() const {
114 assert(Var.isVariable() && "Invalid complex DbgVariable!");
115 return Var.isBlockByrefVariable(DD->getTypeIdentifierMap());
118 DIType DbgVariable::getType() const {
119 DIType Ty = Var.getType().resolve(DD->getTypeIdentifierMap());
120 // FIXME: isBlockByrefVariable should be reformulated in terms of complex
121 // addresses instead.
122 if (Var.isBlockByrefVariable(DD->getTypeIdentifierMap())) {
123 /* Byref variables, in Blocks, are declared by the programmer as
124 "SomeType VarName;", but the compiler creates a
125 __Block_byref_x_VarName struct, and gives the variable VarName
126 either the struct, or a pointer to the struct, as its type. This
127 is necessary for various behind-the-scenes things the compiler
128 needs to do with by-reference variables in blocks.
130 However, as far as the original *programmer* is concerned, the
131 variable should still have type 'SomeType', as originally declared.
133 The following function dives into the __Block_byref_x_VarName
134 struct to find the original type of the variable. This will be
135 passed back to the code generating the type for the Debug
136 Information Entry for the variable 'VarName'. 'VarName' will then
137 have the original type 'SomeType' in its debug information.
139 The original type 'SomeType' will be the type of the field named
140 'VarName' inside the __Block_byref_x_VarName struct.
142 NOTE: In order for this to not completely fail on the debugger
143 side, the Debug Information Entry for the variable VarName needs to
144 have a DW_AT_location that tells the debugger how to unwind through
145 the pointers and __Block_byref_x_VarName struct to find the actual
146 value of the variable. The function addBlockByrefType does this. */
148 uint16_t tag = Ty.getTag();
150 if (tag == dwarf::DW_TAG_pointer_type)
151 subType = resolve(DIDerivedType(Ty).getTypeDerivedFrom());
153 DIArray Elements = DICompositeType(subType).getElements();
154 for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) {
155 DIDerivedType DT(Elements.getElement(i));
156 if (getName() == DT.getName())
157 return (resolve(DT.getTypeDerivedFrom()));
163 static LLVM_CONSTEXPR DwarfAccelTable::Atom TypeAtoms[] = {
164 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, dwarf::DW_FORM_data4),
165 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_tag, dwarf::DW_FORM_data2),
166 DwarfAccelTable::Atom(dwarf::DW_ATOM_type_flags, dwarf::DW_FORM_data1)};
168 DwarfDebug::DwarfDebug(AsmPrinter *A, Module *M)
169 : Asm(A), MMI(Asm->MMI), FirstCU(nullptr), PrevLabel(nullptr),
170 GlobalRangeCount(0), InfoHolder(A, "info_string", DIEValueAllocator),
171 UsedNonDefaultText(false),
172 SkeletonHolder(A, "skel_string", DIEValueAllocator),
173 AccelNames(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset,
174 dwarf::DW_FORM_data4)),
175 AccelObjC(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset,
176 dwarf::DW_FORM_data4)),
177 AccelNamespace(DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset,
178 dwarf::DW_FORM_data4)),
179 AccelTypes(TypeAtoms) {
181 DwarfInfoSectionSym = DwarfAbbrevSectionSym = DwarfStrSectionSym = nullptr;
182 DwarfDebugRangeSectionSym = DwarfDebugLocSectionSym = nullptr;
183 DwarfLineSectionSym = nullptr;
184 DwarfAddrSectionSym = nullptr;
185 DwarfAbbrevDWOSectionSym = DwarfStrDWOSectionSym = nullptr;
186 FunctionBeginSym = FunctionEndSym = nullptr;
190 // Turn on accelerator tables for Darwin by default, pubnames by
191 // default for non-Darwin, and handle split dwarf.
192 bool IsDarwin = Triple(A->getTargetTriple()).isOSDarwin();
194 if (DwarfAccelTables == Default)
195 HasDwarfAccelTables = IsDarwin;
197 HasDwarfAccelTables = DwarfAccelTables == Enable;
199 if (SplitDwarf == Default)
200 HasSplitDwarf = false;
202 HasSplitDwarf = SplitDwarf == Enable;
204 if (DwarfPubSections == Default)
205 HasDwarfPubSections = !IsDarwin;
207 HasDwarfPubSections = DwarfPubSections == Enable;
209 unsigned DwarfVersionNumber = Asm->TM.Options.MCOptions.DwarfVersion;
210 DwarfVersion = DwarfVersionNumber ? DwarfVersionNumber
211 : MMI->getModule()->getDwarfVersion();
213 Asm->OutStreamer.getContext().setDwarfVersion(DwarfVersion);
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.getOrCreateSubprogramDIE(SP);
319 attachLowHighPC(SPCU, *SPDie, FunctionBeginSym, FunctionEndSym);
321 const TargetRegisterInfo *RI = Asm->TM.getRegisterInfo();
322 MachineLocation Location(RI->getFrameRegister(*Asm->MF));
323 SPCU.addAddress(*SPDie, dwarf::DW_AT_frame_base, Location);
325 // Add name to the name table, we do this here because we're guaranteed
326 // to have concrete versions of our DW_TAG_subprogram nodes.
327 addSubprogramNames(SP, *SPDie);
332 /// Check whether we should create a DIE for the given Scope, return true
333 /// if we don't create a DIE (the corresponding DIE is null).
334 bool DwarfDebug::isLexicalScopeDIENull(LexicalScope *Scope) {
335 if (Scope->isAbstractScope())
338 // We don't create a DIE if there is no Range.
339 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges();
343 if (Ranges.size() > 1)
346 // We don't create a DIE if we have a single Range and the end label
348 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin();
349 MCSymbol *End = getLabelAfterInsn(RI->second);
353 static void addSectionLabel(AsmPrinter &Asm, DwarfUnit &U, DIE &D,
354 dwarf::Attribute A, const MCSymbol *L,
355 const MCSymbol *Sec) {
356 if (Asm.MAI->doesDwarfUseRelocationsAcrossSections())
357 U.addSectionLabel(D, A, L);
359 U.addSectionDelta(D, A, L, Sec);
362 void DwarfDebug::addScopeRangeList(DwarfCompileUnit &TheCU, DIE &ScopeDIE,
363 const SmallVectorImpl<InsnRange> &Range) {
364 // Emit offset in .debug_range as a relocatable label. emitDIE will handle
365 // emitting it appropriately.
366 MCSymbol *RangeSym = Asm->GetTempSymbol("debug_ranges", GlobalRangeCount++);
368 // Under fission, ranges are specified by constant offsets relative to the
369 // CU's DW_AT_GNU_ranges_base.
371 TheCU.addSectionDelta(ScopeDIE, dwarf::DW_AT_ranges, RangeSym,
372 DwarfDebugRangeSectionSym);
374 addSectionLabel(*Asm, TheCU, ScopeDIE, dwarf::DW_AT_ranges, RangeSym,
375 DwarfDebugRangeSectionSym);
377 RangeSpanList List(RangeSym);
378 for (const InsnRange &R : Range) {
379 RangeSpan Span(getLabelBeforeInsn(R.first), getLabelAfterInsn(R.second));
380 List.addRange(std::move(Span));
383 // Add the range list to the set of ranges to be emitted.
384 TheCU.addRangeList(std::move(List));
387 void DwarfDebug::attachRangesOrLowHighPC(DwarfCompileUnit &TheCU, DIE &Die,
388 const SmallVectorImpl<InsnRange> &Ranges) {
389 assert(!Ranges.empty());
390 if (Ranges.size() == 1)
391 attachLowHighPC(TheCU, Die, getLabelBeforeInsn(Ranges.front().first),
392 getLabelAfterInsn(Ranges.front().second));
394 addScopeRangeList(TheCU, Die, Ranges);
397 // Construct new DW_TAG_lexical_block for this scope and attach
398 // DW_AT_low_pc/DW_AT_high_pc labels.
400 DwarfDebug::constructLexicalScopeDIE(DwarfCompileUnit &TheCU,
401 LexicalScope *Scope) {
402 if (isLexicalScopeDIENull(Scope))
405 auto ScopeDIE = make_unique<DIE>(dwarf::DW_TAG_lexical_block);
406 if (Scope->isAbstractScope())
409 attachRangesOrLowHighPC(TheCU, *ScopeDIE, Scope->getRanges());
414 // This scope represents inlined body of a function. Construct DIE to
415 // represent this concrete inlined copy of the function.
417 DwarfDebug::constructInlinedScopeDIE(DwarfCompileUnit &TheCU,
418 LexicalScope *Scope) {
419 assert(Scope->getScopeNode());
420 DIScope DS(Scope->getScopeNode());
421 DISubprogram InlinedSP = getDISubprogram(DS);
422 // Find the subprogram's DwarfCompileUnit in the SPMap in case the subprogram
423 // was inlined from another compile unit.
424 DIE *OriginDIE = AbstractSPDies[InlinedSP];
425 assert(OriginDIE && "Unable to find original DIE for an inlined subprogram.");
427 auto ScopeDIE = make_unique<DIE>(dwarf::DW_TAG_inlined_subroutine);
428 TheCU.addDIEEntry(*ScopeDIE, dwarf::DW_AT_abstract_origin, *OriginDIE);
430 attachRangesOrLowHighPC(TheCU, *ScopeDIE, Scope->getRanges());
432 InlinedSubprogramDIEs.insert(OriginDIE);
434 // Add the call site information to the DIE.
435 DILocation DL(Scope->getInlinedAt());
436 TheCU.addUInt(*ScopeDIE, dwarf::DW_AT_call_file, None,
437 TheCU.getOrCreateSourceID(DL.getFilename(), DL.getDirectory()));
438 TheCU.addUInt(*ScopeDIE, dwarf::DW_AT_call_line, None, DL.getLineNumber());
440 // Add name to the name table, we do this here because we're guaranteed
441 // to have concrete versions of our DW_TAG_inlined_subprogram nodes.
442 addSubprogramNames(InlinedSP, *ScopeDIE);
447 static std::unique_ptr<DIE> constructVariableDIE(DwarfCompileUnit &TheCU,
449 const LexicalScope &Scope,
450 DIE *&ObjectPointer) {
451 auto Var = TheCU.constructVariableDIE(DV, Scope.isAbstractScope());
452 if (DV.isObjectPointer())
453 ObjectPointer = Var.get();
457 DIE *DwarfDebug::createScopeChildrenDIE(
458 DwarfCompileUnit &TheCU, LexicalScope *Scope,
459 SmallVectorImpl<std::unique_ptr<DIE>> &Children) {
460 DIE *ObjectPointer = nullptr;
462 // Collect arguments for current function.
463 if (LScopes.isCurrentFunctionScope(Scope)) {
464 for (DbgVariable *ArgDV : CurrentFnArguments)
467 constructVariableDIE(TheCU, *ArgDV, *Scope, ObjectPointer));
469 // If this is a variadic function, add an unspecified parameter.
470 DISubprogram SP(Scope->getScopeNode());
471 DITypeArray FnArgs = SP.getType().getTypeArray();
472 if (resolve(FnArgs.getElement(FnArgs.getNumElements() - 1))
473 .isUnspecifiedParameter()) {
475 make_unique<DIE>(dwarf::DW_TAG_unspecified_parameters));
479 // Collect lexical scope children first.
480 for (DbgVariable *DV : ScopeVariables.lookup(Scope))
481 Children.push_back(constructVariableDIE(TheCU, *DV, *Scope, ObjectPointer));
483 for (LexicalScope *LS : Scope->getChildren())
484 if (std::unique_ptr<DIE> Nested = constructScopeDIE(TheCU, LS))
485 Children.push_back(std::move(Nested));
486 return ObjectPointer;
489 void DwarfDebug::createAndAddScopeChildren(DwarfCompileUnit &TheCU,
490 LexicalScope *Scope, DIE &ScopeDIE) {
491 // We create children when the scope DIE is not null.
492 SmallVector<std::unique_ptr<DIE>, 8> Children;
493 if (DIE *ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children))
494 TheCU.addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, *ObjectPointer);
497 for (auto &I : Children)
498 ScopeDIE.addChild(std::move(I));
501 void DwarfDebug::constructAbstractSubprogramScopeDIE(DwarfCompileUnit &TheCU,
502 LexicalScope *Scope) {
503 assert(Scope && Scope->getScopeNode());
504 assert(Scope->isAbstractScope());
505 assert(!Scope->getInlinedAt());
507 DISubprogram SP(Scope->getScopeNode());
509 ProcessedSPNodes.insert(SP);
511 DIE *&AbsDef = AbstractSPDies[SP];
515 // Find the subprogram's DwarfCompileUnit in the SPMap in case the subprogram
516 // was inlined from another compile unit.
517 DwarfCompileUnit &SPCU = *SPMap[SP];
520 // Some of this is duplicated from DwarfUnit::getOrCreateSubprogramDIE, with
521 // the important distinction that the DIDescriptor is not associated with the
522 // DIE (since the DIDescriptor will be associated with the concrete DIE, if
523 // any). It could be refactored to some common utility function.
524 if (DISubprogram SPDecl = SP.getFunctionDeclaration()) {
525 ContextDIE = &SPCU.getUnitDie();
526 SPCU.getOrCreateSubprogramDIE(SPDecl);
528 ContextDIE = SPCU.getOrCreateContextDIE(resolve(SP.getContext()));
530 // Passing null as the associated DIDescriptor because the abstract definition
531 // shouldn't be found by lookup.
532 AbsDef = &SPCU.createAndAddDIE(dwarf::DW_TAG_subprogram, *ContextDIE,
534 SPCU.applySubprogramAttributesToDefinition(SP, *AbsDef);
536 SPCU.addUInt(*AbsDef, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined);
537 createAndAddScopeChildren(SPCU, Scope, *AbsDef);
540 DIE &DwarfDebug::constructSubprogramScopeDIE(DwarfCompileUnit &TheCU,
541 LexicalScope *Scope) {
542 assert(Scope && Scope->getScopeNode());
543 assert(!Scope->getInlinedAt());
544 assert(!Scope->isAbstractScope());
545 DISubprogram Sub(Scope->getScopeNode());
547 assert(Sub.isSubprogram());
549 ProcessedSPNodes.insert(Sub);
551 DIE &ScopeDIE = updateSubprogramScopeDIE(TheCU, Sub);
553 createAndAddScopeChildren(TheCU, Scope, ScopeDIE);
558 // Construct a DIE for this scope.
559 std::unique_ptr<DIE> DwarfDebug::constructScopeDIE(DwarfCompileUnit &TheCU,
560 LexicalScope *Scope) {
561 if (!Scope || !Scope->getScopeNode())
564 DIScope DS(Scope->getScopeNode());
566 assert((Scope->getInlinedAt() || !DS.isSubprogram()) &&
567 "Only handle inlined subprograms here, use "
568 "constructSubprogramScopeDIE for non-inlined "
571 SmallVector<std::unique_ptr<DIE>, 8> Children;
573 // We try to create the scope DIE first, then the children DIEs. This will
574 // avoid creating un-used children then removing them later when we find out
575 // the scope DIE is null.
576 std::unique_ptr<DIE> ScopeDIE;
577 if (Scope->getParent() && DS.isSubprogram()) {
578 ScopeDIE = constructInlinedScopeDIE(TheCU, Scope);
581 // We create children when the scope DIE is not null.
582 createScopeChildrenDIE(TheCU, Scope, Children);
584 // Early exit when we know the scope DIE is going to be null.
585 if (isLexicalScopeDIENull(Scope))
588 // We create children here when we know the scope DIE is not going to be
589 // null and the children will be added to the scope DIE.
590 createScopeChildrenDIE(TheCU, Scope, Children);
592 // There is no need to emit empty lexical block DIE.
593 std::pair<ImportedEntityMap::const_iterator,
594 ImportedEntityMap::const_iterator> Range =
595 std::equal_range(ScopesWithImportedEntities.begin(),
596 ScopesWithImportedEntities.end(),
597 std::pair<const MDNode *, const MDNode *>(DS, nullptr),
599 if (Children.empty() && Range.first == Range.second)
601 ScopeDIE = constructLexicalScopeDIE(TheCU, Scope);
602 assert(ScopeDIE && "Scope DIE should not be null.");
603 for (ImportedEntityMap::const_iterator i = Range.first; i != Range.second;
605 constructImportedEntityDIE(TheCU, i->second, *ScopeDIE);
609 for (auto &I : Children)
610 ScopeDIE->addChild(std::move(I));
615 void DwarfDebug::addGnuPubAttributes(DwarfUnit &U, DIE &D) const {
616 if (!GenerateGnuPubSections)
619 U.addFlag(D, dwarf::DW_AT_GNU_pubnames);
622 // Create new DwarfCompileUnit for the given metadata node with tag
623 // DW_TAG_compile_unit.
624 DwarfCompileUnit &DwarfDebug::constructDwarfCompileUnit(DICompileUnit DIUnit) {
625 StringRef FN = DIUnit.getFilename();
626 CompilationDir = DIUnit.getDirectory();
628 auto OwnedUnit = make_unique<DwarfCompileUnit>(
629 InfoHolder.getUnits().size(), DIUnit, Asm, this, &InfoHolder);
630 DwarfCompileUnit &NewCU = *OwnedUnit;
631 DIE &Die = NewCU.getUnitDie();
632 InfoHolder.addUnit(std::move(OwnedUnit));
634 // LTO with assembly output shares a single line table amongst multiple CUs.
635 // To avoid the compilation directory being ambiguous, let the line table
636 // explicitly describe the directory of all files, never relying on the
637 // compilation directory.
638 if (!Asm->OutStreamer.hasRawTextSupport() || SingleCU)
639 Asm->OutStreamer.getContext().setMCLineTableCompilationDir(
640 NewCU.getUniqueID(), CompilationDir);
642 NewCU.addString(Die, dwarf::DW_AT_producer, DIUnit.getProducer());
643 NewCU.addUInt(Die, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
644 DIUnit.getLanguage());
645 NewCU.addString(Die, dwarf::DW_AT_name, FN);
647 if (!useSplitDwarf()) {
648 NewCU.initStmtList(DwarfLineSectionSym);
650 // If we're using split dwarf the compilation dir is going to be in the
651 // skeleton CU and so we don't need to duplicate it here.
652 if (!CompilationDir.empty())
653 NewCU.addString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
655 addGnuPubAttributes(NewCU, Die);
658 if (DIUnit.isOptimized())
659 NewCU.addFlag(Die, dwarf::DW_AT_APPLE_optimized);
661 StringRef Flags = DIUnit.getFlags();
663 NewCU.addString(Die, dwarf::DW_AT_APPLE_flags, Flags);
665 if (unsigned RVer = DIUnit.getRunTimeVersion())
666 NewCU.addUInt(Die, dwarf::DW_AT_APPLE_major_runtime_vers,
667 dwarf::DW_FORM_data1, RVer);
672 if (useSplitDwarf()) {
673 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoDWOSection(),
674 DwarfInfoDWOSectionSym);
675 NewCU.setSkeleton(constructSkeletonCU(NewCU));
677 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
678 DwarfInfoSectionSym);
680 CUMap.insert(std::make_pair(DIUnit, &NewCU));
681 CUDieMap.insert(std::make_pair(&Die, &NewCU));
685 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
687 DIImportedEntity Module(N);
688 assert(Module.Verify());
689 if (DIE *D = TheCU.getOrCreateContextDIE(Module.getContext()))
690 constructImportedEntityDIE(TheCU, Module, *D);
693 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
694 const MDNode *N, DIE &Context) {
695 DIImportedEntity Module(N);
696 assert(Module.Verify());
697 return constructImportedEntityDIE(TheCU, Module, Context);
700 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
701 const DIImportedEntity &Module,
703 assert(Module.Verify() &&
704 "Use one of the MDNode * overloads to handle invalid metadata");
705 DIE &IMDie = TheCU.createAndAddDIE(Module.getTag(), Context, Module);
707 DIDescriptor Entity = resolve(Module.getEntity());
708 if (Entity.isNameSpace())
709 EntityDie = TheCU.getOrCreateNameSpace(DINameSpace(Entity));
710 else if (Entity.isSubprogram())
711 EntityDie = TheCU.getOrCreateSubprogramDIE(DISubprogram(Entity));
712 else if (Entity.isType())
713 EntityDie = TheCU.getOrCreateTypeDIE(DIType(Entity));
715 EntityDie = TheCU.getDIE(Entity);
716 TheCU.addSourceLine(IMDie, Module.getLineNumber(),
717 Module.getContext().getFilename(),
718 Module.getContext().getDirectory());
719 TheCU.addDIEEntry(IMDie, dwarf::DW_AT_import, *EntityDie);
720 StringRef Name = Module.getName();
722 TheCU.addString(IMDie, dwarf::DW_AT_name, Name);
725 // Emit all Dwarf sections that should come prior to the content. Create
726 // global DIEs and emit initial debug info sections. This is invoked by
727 // the target AsmPrinter.
728 void DwarfDebug::beginModule() {
729 if (DisableDebugInfoPrinting)
732 const Module *M = MMI->getModule();
734 FunctionDIs = makeSubprogramMap(*M);
736 // If module has named metadata anchors then use them, otherwise scan the
737 // module using debug info finder to collect debug info.
738 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
741 TypeIdentifierMap = generateDITypeIdentifierMap(CU_Nodes);
743 // Emit initial sections so we can reference labels later.
746 SingleCU = CU_Nodes->getNumOperands() == 1;
748 for (MDNode *N : CU_Nodes->operands()) {
749 DICompileUnit CUNode(N);
750 DwarfCompileUnit &CU = constructDwarfCompileUnit(CUNode);
751 DIArray ImportedEntities = CUNode.getImportedEntities();
752 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
753 ScopesWithImportedEntities.push_back(std::make_pair(
754 DIImportedEntity(ImportedEntities.getElement(i)).getContext(),
755 ImportedEntities.getElement(i)));
756 std::sort(ScopesWithImportedEntities.begin(),
757 ScopesWithImportedEntities.end(), less_first());
758 DIArray GVs = CUNode.getGlobalVariables();
759 for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i)
760 CU.createGlobalVariableDIE(DIGlobalVariable(GVs.getElement(i)));
761 DIArray SPs = CUNode.getSubprograms();
762 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i)
763 SPMap.insert(std::make_pair(SPs.getElement(i), &CU));
764 DIArray EnumTypes = CUNode.getEnumTypes();
765 for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i) {
766 DIType Ty(EnumTypes.getElement(i));
767 // The enum types array by design contains pointers to
768 // MDNodes rather than DIRefs. Unique them here.
769 DIType UniqueTy(resolve(Ty.getRef()));
770 CU.getOrCreateTypeDIE(UniqueTy);
772 DIArray RetainedTypes = CUNode.getRetainedTypes();
773 for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i) {
774 DIType Ty(RetainedTypes.getElement(i));
775 // The retained types array by design contains pointers to
776 // MDNodes rather than DIRefs. Unique them here.
777 DIType UniqueTy(resolve(Ty.getRef()));
778 CU.getOrCreateTypeDIE(UniqueTy);
780 // Emit imported_modules last so that the relevant context is already
782 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
783 constructImportedEntityDIE(CU, ImportedEntities.getElement(i));
786 // Tell MMI that we have debug info.
787 MMI->setDebugInfoAvailability(true);
789 // Prime section data.
790 SectionMap[Asm->getObjFileLowering().getTextSection()];
793 void DwarfDebug::finishVariableDefinitions() {
794 for (const auto &Var : ConcreteVariables) {
795 DIE *VariableDie = Var->getDIE();
796 // FIXME: There shouldn't be any variables without DIEs.
799 // FIXME: Consider the time-space tradeoff of just storing the unit pointer
800 // in the ConcreteVariables list, rather than looking it up again here.
801 // DIE::getUnit isn't simple - it walks parent pointers, etc.
802 DwarfCompileUnit *Unit = lookupUnit(VariableDie->getUnit());
804 DbgVariable *AbsVar = getExistingAbstractVariable(Var->getVariable());
805 if (AbsVar && AbsVar->getDIE()) {
806 Unit->addDIEEntry(*VariableDie, dwarf::DW_AT_abstract_origin,
809 Unit->applyVariableAttributes(*Var, *VariableDie);
813 void DwarfDebug::finishSubprogramDefinitions() {
814 const Module *M = MMI->getModule();
816 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
817 for (MDNode *N : CU_Nodes->operands()) {
818 DICompileUnit TheCU(N);
819 // Construct subprogram DIE and add variables DIEs.
820 DwarfCompileUnit *SPCU =
821 static_cast<DwarfCompileUnit *>(CUMap.lookup(TheCU));
822 DIArray Subprograms = TheCU.getSubprograms();
823 for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) {
824 DISubprogram SP(Subprograms.getElement(i));
825 // Perhaps the subprogram is in another CU (such as due to comdat
826 // folding, etc), in which case ignore it here.
827 if (SPMap[SP] != SPCU)
829 DIE *D = SPCU->getDIE(SP);
830 if (DIE *AbsSPDIE = AbstractSPDies.lookup(SP)) {
832 // If this subprogram has an abstract definition, reference that
833 SPCU->addDIEEntry(*D, dwarf::DW_AT_abstract_origin, *AbsSPDIE);
836 // Lazily construct the subprogram if we didn't see either concrete or
837 // inlined versions during codegen.
838 D = SPCU->getOrCreateSubprogramDIE(SP);
839 // And attach the attributes
840 SPCU->applySubprogramAttributesToDefinition(SP, *D);
847 // Collect info for variables that were optimized out.
848 void DwarfDebug::collectDeadVariables() {
849 const Module *M = MMI->getModule();
851 if (NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu")) {
852 for (MDNode *N : CU_Nodes->operands()) {
853 DICompileUnit TheCU(N);
854 // Construct subprogram DIE and add variables DIEs.
855 DwarfCompileUnit *SPCU =
856 static_cast<DwarfCompileUnit *>(CUMap.lookup(TheCU));
857 assert(SPCU && "Unable to find Compile Unit!");
858 DIArray Subprograms = TheCU.getSubprograms();
859 for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) {
860 DISubprogram SP(Subprograms.getElement(i));
861 if (ProcessedSPNodes.count(SP) != 0)
863 assert(SP.isSubprogram() &&
864 "CU's subprogram list contains a non-subprogram");
865 assert(SP.isDefinition() &&
866 "CU's subprogram list contains a subprogram declaration");
867 DIArray Variables = SP.getVariables();
868 if (Variables.getNumElements() == 0)
871 DIE *SPDIE = AbstractSPDies.lookup(SP);
873 SPDIE = SPCU->getDIE(SP);
875 for (unsigned vi = 0, ve = Variables.getNumElements(); vi != ve; ++vi) {
876 DIVariable DV(Variables.getElement(vi));
877 assert(DV.isVariable());
878 DbgVariable NewVar(DV, this);
879 auto VariableDie = SPCU->constructVariableDIE(NewVar);
880 SPCU->applyVariableAttributes(NewVar, *VariableDie);
881 SPDIE->addChild(std::move(VariableDie));
888 void DwarfDebug::finalizeModuleInfo() {
889 finishSubprogramDefinitions();
891 finishVariableDefinitions();
893 // Collect info for variables that were optimized out.
894 collectDeadVariables();
896 // Handle anything that needs to be done on a per-unit basis after
897 // all other generation.
898 for (const auto &TheU : getUnits()) {
899 // Emit DW_AT_containing_type attribute to connect types with their
900 // vtable holding type.
901 TheU->constructContainingTypeDIEs();
903 // Add CU specific attributes if we need to add any.
904 if (TheU->getUnitDie().getTag() == dwarf::DW_TAG_compile_unit) {
905 // If we're splitting the dwarf out now that we've got the entire
906 // CU then add the dwo id to it.
907 DwarfCompileUnit *SkCU =
908 static_cast<DwarfCompileUnit *>(TheU->getSkeleton());
909 if (useSplitDwarf()) {
910 // Emit a unique identifier for this CU.
911 uint64_t ID = DIEHash(Asm).computeCUSignature(TheU->getUnitDie());
912 TheU->addUInt(TheU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
913 dwarf::DW_FORM_data8, ID);
914 SkCU->addUInt(SkCU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
915 dwarf::DW_FORM_data8, ID);
917 // We don't keep track of which addresses are used in which CU so this
918 // is a bit pessimistic under LTO.
919 if (!AddrPool.isEmpty())
920 addSectionLabel(*Asm, *SkCU, SkCU->getUnitDie(),
921 dwarf::DW_AT_GNU_addr_base, DwarfAddrSectionSym,
922 DwarfAddrSectionSym);
923 if (!TheU->getRangeLists().empty())
924 addSectionLabel(*Asm, *SkCU, SkCU->getUnitDie(),
925 dwarf::DW_AT_GNU_ranges_base,
926 DwarfDebugRangeSectionSym, DwarfDebugRangeSectionSym);
929 // If we have code split among multiple sections or non-contiguous
930 // ranges of code then emit a DW_AT_ranges attribute on the unit that will
931 // remain in the .o file, otherwise add a DW_AT_low_pc.
932 // FIXME: We should use ranges allow reordering of code ala
933 // .subsections_via_symbols in mach-o. This would mean turning on
934 // ranges for all subprogram DIEs for mach-o.
935 DwarfCompileUnit &U =
936 SkCU ? *SkCU : static_cast<DwarfCompileUnit &>(*TheU);
937 unsigned NumRanges = TheU->getRanges().size();
940 addSectionLabel(*Asm, U, U.getUnitDie(), dwarf::DW_AT_ranges,
941 Asm->GetTempSymbol("cu_ranges", U.getUniqueID()),
942 DwarfDebugRangeSectionSym);
944 // A DW_AT_low_pc attribute may also be specified in combination with
945 // DW_AT_ranges to specify the default base address for use in
946 // location lists (see Section 2.6.2) and range lists (see Section
948 U.addUInt(U.getUnitDie(), dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr,
951 RangeSpan &Range = TheU->getRanges().back();
952 U.addLocalLabelAddress(U.getUnitDie(), dwarf::DW_AT_low_pc,
954 U.addLabelDelta(U.getUnitDie(), dwarf::DW_AT_high_pc, Range.getEnd(),
961 // Compute DIE offsets and sizes.
962 InfoHolder.computeSizeAndOffsets();
964 SkeletonHolder.computeSizeAndOffsets();
967 void DwarfDebug::endSections() {
968 // Filter labels by section.
969 for (const SymbolCU &SCU : ArangeLabels) {
970 if (SCU.Sym->isInSection()) {
971 // Make a note of this symbol and it's section.
972 const MCSection *Section = &SCU.Sym->getSection();
973 if (!Section->getKind().isMetadata())
974 SectionMap[Section].push_back(SCU);
976 // Some symbols (e.g. common/bss on mach-o) can have no section but still
977 // appear in the output. This sucks as we rely on sections to build
978 // arange spans. We can do it without, but it's icky.
979 SectionMap[nullptr].push_back(SCU);
983 // Build a list of sections used.
984 std::vector<const MCSection *> Sections;
985 for (const auto &it : SectionMap) {
986 const MCSection *Section = it.first;
987 Sections.push_back(Section);
990 // Sort the sections into order.
991 // This is only done to ensure consistent output order across different runs.
992 std::sort(Sections.begin(), Sections.end(), SectionSort);
994 // Add terminating symbols for each section.
995 for (unsigned ID = 0, E = Sections.size(); ID != E; ID++) {
996 const MCSection *Section = Sections[ID];
997 MCSymbol *Sym = nullptr;
1000 // We can't call MCSection::getLabelEndName, as it's only safe to do so
1001 // if we know the section name up-front. For user-created sections, the
1002 // resulting label may not be valid to use as a label. (section names can
1003 // use a greater set of characters on some systems)
1004 Sym = Asm->GetTempSymbol("debug_end", ID);
1005 Asm->OutStreamer.SwitchSection(Section);
1006 Asm->OutStreamer.EmitLabel(Sym);
1009 // Insert a final terminator.
1010 SectionMap[Section].push_back(SymbolCU(nullptr, Sym));
1014 // Emit all Dwarf sections that should come after the content.
1015 void DwarfDebug::endModule() {
1016 assert(CurFn == nullptr);
1017 assert(CurMI == nullptr);
1022 // End any existing sections.
1023 // TODO: Does this need to happen?
1026 // Finalize the debug info for the module.
1027 finalizeModuleInfo();
1031 // Emit all the DIEs into a debug info section.
1034 // Corresponding abbreviations into a abbrev section.
1035 emitAbbreviations();
1037 // Emit info into a debug aranges section.
1038 if (GenerateARangeSection)
1041 // Emit info into a debug ranges section.
1044 if (useSplitDwarf()) {
1047 emitDebugAbbrevDWO();
1050 // Emit DWO addresses.
1051 AddrPool.emit(*Asm, Asm->getObjFileLowering().getDwarfAddrSection());
1053 // Emit info into a debug loc section.
1056 // Emit info into the dwarf accelerator table sections.
1057 if (useDwarfAccelTables()) {
1060 emitAccelNamespaces();
1064 // Emit the pubnames and pubtypes sections if requested.
1065 if (HasDwarfPubSections) {
1066 emitDebugPubNames(GenerateGnuPubSections);
1067 emitDebugPubTypes(GenerateGnuPubSections);
1072 AbstractVariables.clear();
1074 // Reset these for the next Module if we have one.
1078 // Find abstract variable, if any, associated with Var.
1079 DbgVariable *DwarfDebug::getExistingAbstractVariable(const DIVariable &DV,
1080 DIVariable &Cleansed) {
1081 LLVMContext &Ctx = DV->getContext();
1082 // More then one inlined variable corresponds to one abstract variable.
1083 // FIXME: This duplication of variables when inlining should probably be
1084 // removed. It's done to allow each DIVariable to describe its location
1085 // because the DebugLoc on the dbg.value/declare isn't accurate. We should
1086 // make it accurate then remove this duplication/cleansing stuff.
1087 Cleansed = cleanseInlinedVariable(DV, Ctx);
1088 auto I = AbstractVariables.find(Cleansed);
1089 if (I != AbstractVariables.end())
1090 return I->second.get();
1094 DbgVariable *DwarfDebug::getExistingAbstractVariable(const DIVariable &DV) {
1095 DIVariable Cleansed;
1096 return getExistingAbstractVariable(DV, Cleansed);
1099 void DwarfDebug::createAbstractVariable(const DIVariable &Var,
1100 LexicalScope *Scope) {
1101 auto AbsDbgVariable = make_unique<DbgVariable>(Var, this);
1102 addScopeVariable(Scope, AbsDbgVariable.get());
1103 AbstractVariables[Var] = std::move(AbsDbgVariable);
1106 void DwarfDebug::ensureAbstractVariableIsCreated(const DIVariable &DV,
1107 const MDNode *ScopeNode) {
1108 DIVariable Cleansed = DV;
1109 if (getExistingAbstractVariable(DV, Cleansed))
1112 createAbstractVariable(Cleansed, LScopes.getOrCreateAbstractScope(ScopeNode));
1116 DwarfDebug::ensureAbstractVariableIsCreatedIfScoped(const DIVariable &DV,
1117 const MDNode *ScopeNode) {
1118 DIVariable Cleansed = DV;
1119 if (getExistingAbstractVariable(DV, Cleansed))
1122 if (LexicalScope *Scope = LScopes.findAbstractScope(ScopeNode))
1123 createAbstractVariable(Cleansed, Scope);
1126 // If Var is a current function argument then add it to CurrentFnArguments list.
1127 bool DwarfDebug::addCurrentFnArgument(DbgVariable *Var, LexicalScope *Scope) {
1128 if (!LScopes.isCurrentFunctionScope(Scope))
1130 DIVariable DV = Var->getVariable();
1131 if (DV.getTag() != dwarf::DW_TAG_arg_variable)
1133 unsigned ArgNo = DV.getArgNumber();
1137 size_t Size = CurrentFnArguments.size();
1139 CurrentFnArguments.resize(CurFn->getFunction()->arg_size());
1140 // llvm::Function argument size is not good indicator of how many
1141 // arguments does the function have at source level.
1143 CurrentFnArguments.resize(ArgNo * 2);
1144 CurrentFnArguments[ArgNo - 1] = Var;
1148 // Collect variable information from side table maintained by MMI.
1149 void DwarfDebug::collectVariableInfoFromMMITable(
1150 SmallPtrSet<const MDNode *, 16> &Processed) {
1151 for (const auto &VI : MMI->getVariableDbgInfo()) {
1154 Processed.insert(VI.Var);
1155 DIVariable DV(VI.Var);
1156 LexicalScope *Scope = LScopes.findLexicalScope(VI.Loc);
1158 // If variable scope is not found then skip this variable.
1162 ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode());
1163 ConcreteVariables.push_back(make_unique<DbgVariable>(DV, this));
1164 DbgVariable *RegVar = ConcreteVariables.back().get();
1165 RegVar->setFrameIndex(VI.Slot);
1166 addScopeVariable(Scope, RegVar);
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 auto &I : DbgValues) {
1205 DIVariable DV(I.first);
1206 if (Processed.count(DV))
1209 // Instruction ranges, specifying where DV is accessible.
1210 const auto &Ranges = I.second;
1214 LexicalScope *Scope = nullptr;
1215 if (DV.getTag() == dwarf::DW_TAG_arg_variable &&
1216 DISubprogram(DV.getContext()).describes(CurFn->getFunction()))
1217 Scope = LScopes.getCurrentFunctionScope();
1218 else if (MDNode *IA = DV.getInlinedAt()) {
1219 DebugLoc DL = DebugLoc::getFromDILocation(IA);
1220 Scope = LScopes.findInlinedScope(DebugLoc::get(
1221 DL.getLine(), DL.getCol(), DV.getContext(), IA));
1223 Scope = LScopes.findLexicalScope(DV.getContext());
1224 // If variable scope is not found then skip this variable.
1228 Processed.insert(DV);
1229 const MachineInstr *MInsn = Ranges.front().first;
1230 assert(MInsn->isDebugValue() && "History must begin with debug value");
1231 ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode());
1232 ConcreteVariables.push_back(make_unique<DbgVariable>(MInsn, this));
1233 DbgVariable *RegVar = ConcreteVariables.back().get();
1234 addScopeVariable(Scope, RegVar);
1236 // Check if the first DBG_VALUE is valid for the rest of the function.
1237 if (Ranges.size() == 1 && Ranges.front().second == nullptr)
1240 // Handle multiple DBG_VALUE instructions describing one variable.
1241 RegVar->setDotDebugLocOffset(DotDebugLocEntries.size());
1243 DotDebugLocEntries.resize(DotDebugLocEntries.size() + 1);
1244 DebugLocList &LocList = DotDebugLocEntries.back();
1246 Asm->GetTempSymbol("debug_loc", DotDebugLocEntries.size() - 1);
1247 SmallVector<DebugLocEntry, 4> &DebugLoc = LocList.List;
1248 for (auto I = Ranges.begin(), E = Ranges.end(); I != E; ++I) {
1249 const MachineInstr *Begin = I->first;
1250 const MachineInstr *End = I->second;
1251 assert(Begin->isDebugValue() && "Invalid History entry");
1253 // Check if a variable is unaccessible in this range.
1254 if (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() &&
1255 !Begin->getOperand(0).getReg())
1257 DEBUG(dbgs() << "DotDebugLoc Pair:\n" << "\t" << *Begin);
1259 DEBUG(dbgs() << "\t" << *End);
1261 DEBUG(dbgs() << "\tNULL\n");
1263 const MCSymbol *StartLabel = getLabelBeforeInsn(Begin);
1264 assert(StartLabel && "Forgot label before DBG_VALUE starting a range!");
1266 const MCSymbol *EndLabel;
1268 EndLabel = getLabelAfterInsn(End);
1269 else if (std::next(I) == Ranges.end())
1270 EndLabel = FunctionEndSym;
1272 EndLabel = getLabelBeforeInsn(std::next(I)->first);
1273 assert(EndLabel && "Forgot label after instruction ending a range!");
1275 DebugLocEntry Loc(StartLabel, EndLabel, getDebugLocValue(Begin), TheCU);
1276 if (DebugLoc.empty() || !DebugLoc.back().Merge(Loc))
1277 DebugLoc.push_back(std::move(Loc));
1281 // Collect info for variables that were optimized out.
1282 DIArray Variables = DISubprogram(FnScope->getScopeNode()).getVariables();
1283 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1284 DIVariable DV(Variables.getElement(i));
1285 assert(DV.isVariable());
1286 if (!Processed.insert(DV))
1288 if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext())) {
1289 ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode());
1290 ConcreteVariables.push_back(make_unique<DbgVariable>(DV, this));
1291 addScopeVariable(Scope, ConcreteVariables.back().get());
1296 // Return Label preceding the instruction.
1297 MCSymbol *DwarfDebug::getLabelBeforeInsn(const MachineInstr *MI) {
1298 MCSymbol *Label = LabelsBeforeInsn.lookup(MI);
1299 assert(Label && "Didn't insert label before instruction");
1303 // Return Label immediately following the instruction.
1304 MCSymbol *DwarfDebug::getLabelAfterInsn(const MachineInstr *MI) {
1305 return LabelsAfterInsn.lookup(MI);
1308 // Process beginning of an instruction.
1309 void DwarfDebug::beginInstruction(const MachineInstr *MI) {
1310 assert(CurMI == nullptr);
1312 // Check if source location changes, but ignore DBG_VALUE locations.
1313 if (!MI->isDebugValue()) {
1314 DebugLoc DL = MI->getDebugLoc();
1315 if (DL != PrevInstLoc && (!DL.isUnknown() || UnknownLocations)) {
1318 if (DL == PrologEndLoc) {
1319 Flags |= DWARF2_FLAG_PROLOGUE_END;
1320 PrologEndLoc = DebugLoc();
1322 if (PrologEndLoc.isUnknown())
1323 Flags |= DWARF2_FLAG_IS_STMT;
1325 if (!DL.isUnknown()) {
1326 const MDNode *Scope = DL.getScope(Asm->MF->getFunction()->getContext());
1327 recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags);
1329 recordSourceLine(0, 0, nullptr, 0);
1333 // Insert labels where requested.
1334 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1335 LabelsBeforeInsn.find(MI);
1338 if (I == LabelsBeforeInsn.end())
1341 // Label already assigned.
1346 PrevLabel = MMI->getContext().CreateTempSymbol();
1347 Asm->OutStreamer.EmitLabel(PrevLabel);
1349 I->second = PrevLabel;
1352 // Process end of an instruction.
1353 void DwarfDebug::endInstruction() {
1354 assert(CurMI != nullptr);
1355 // Don't create a new label after DBG_VALUE instructions.
1356 // They don't generate code.
1357 if (!CurMI->isDebugValue())
1358 PrevLabel = nullptr;
1360 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1361 LabelsAfterInsn.find(CurMI);
1365 if (I == LabelsAfterInsn.end())
1368 // Label already assigned.
1372 // We need a label after this instruction.
1374 PrevLabel = MMI->getContext().CreateTempSymbol();
1375 Asm->OutStreamer.EmitLabel(PrevLabel);
1377 I->second = PrevLabel;
1380 // Each LexicalScope has first instruction and last instruction to mark
1381 // beginning and end of a scope respectively. Create an inverse map that list
1382 // scopes starts (and ends) with an instruction. One instruction may start (or
1383 // end) multiple scopes. Ignore scopes that are not reachable.
1384 void DwarfDebug::identifyScopeMarkers() {
1385 SmallVector<LexicalScope *, 4> WorkList;
1386 WorkList.push_back(LScopes.getCurrentFunctionScope());
1387 while (!WorkList.empty()) {
1388 LexicalScope *S = WorkList.pop_back_val();
1390 const SmallVectorImpl<LexicalScope *> &Children = S->getChildren();
1391 if (!Children.empty())
1392 WorkList.append(Children.begin(), Children.end());
1394 if (S->isAbstractScope())
1397 for (const InsnRange &R : S->getRanges()) {
1398 assert(R.first && "InsnRange does not have first instruction!");
1399 assert(R.second && "InsnRange does not have second instruction!");
1400 requestLabelBeforeInsn(R.first);
1401 requestLabelAfterInsn(R.second);
1406 static DebugLoc findPrologueEndLoc(const MachineFunction *MF) {
1407 // First known non-DBG_VALUE and non-frame setup location marks
1408 // the beginning of the function body.
1409 for (const auto &MBB : *MF)
1410 for (const auto &MI : MBB)
1411 if (!MI.isDebugValue() && !MI.getFlag(MachineInstr::FrameSetup) &&
1412 !MI.getDebugLoc().isUnknown())
1413 return MI.getDebugLoc();
1417 // Gather pre-function debug information. Assumes being called immediately
1418 // after the function entry point has been emitted.
1419 void DwarfDebug::beginFunction(const MachineFunction *MF) {
1422 // If there's no debug info for the function we're not going to do anything.
1423 if (!MMI->hasDebugInfo())
1426 auto DI = FunctionDIs.find(MF->getFunction());
1427 if (DI == FunctionDIs.end())
1430 // Grab the lexical scopes for the function, if we don't have any of those
1431 // then we're not going to be able to do anything.
1432 LScopes.initialize(*MF);
1433 if (LScopes.empty())
1436 assert(DbgValues.empty() && "DbgValues map wasn't cleaned!");
1438 // Make sure that each lexical scope will have a begin/end label.
1439 identifyScopeMarkers();
1441 // Set DwarfDwarfCompileUnitID in MCContext to the Compile Unit this function
1442 // belongs to so that we add to the correct per-cu line table in the
1444 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1445 // FnScope->getScopeNode() and DI->second should represent the same function,
1446 // though they may not be the same MDNode due to inline functions merged in
1447 // LTO where the debug info metadata still differs (either due to distinct
1448 // written differences - two versions of a linkonce_odr function
1449 // written/copied into two separate files, or some sub-optimal metadata that
1450 // isn't structurally identical (see: file path/name info from clang, which
1451 // includes the directory of the cpp file being built, even when the file name
1452 // is absolute (such as an <> lookup header)))
1453 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1454 assert(TheCU && "Unable to find compile unit!");
1455 if (Asm->OutStreamer.hasRawTextSupport())
1456 // Use a single line table if we are generating assembly.
1457 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1459 Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID());
1461 // Emit a label for the function so that we have a beginning address.
1462 FunctionBeginSym = Asm->GetTempSymbol("func_begin", Asm->getFunctionNumber());
1463 // Assumes in correct section after the entry point.
1464 Asm->OutStreamer.EmitLabel(FunctionBeginSym);
1466 // Calculate history for local variables.
1467 calculateDbgValueHistory(MF, Asm->TM.getRegisterInfo(), DbgValues);
1469 // Request labels for the full history.
1470 for (const auto &I : DbgValues) {
1471 const auto &Ranges = I.second;
1475 // The first mention of a function argument gets the FunctionBeginSym
1476 // label, so arguments are visible when breaking at function entry.
1477 DIVariable DV(I.first);
1478 if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable &&
1479 getDISubprogram(DV.getContext()).describes(MF->getFunction()))
1480 LabelsBeforeInsn[Ranges.front().first] = FunctionBeginSym;
1482 for (const auto &Range : Ranges) {
1483 requestLabelBeforeInsn(Range.first);
1485 requestLabelAfterInsn(Range.second);
1489 PrevInstLoc = DebugLoc();
1490 PrevLabel = FunctionBeginSym;
1492 // Record beginning of function.
1493 PrologEndLoc = findPrologueEndLoc(MF);
1494 if (!PrologEndLoc.isUnknown()) {
1495 DebugLoc FnStartDL =
1496 PrologEndLoc.getFnDebugLoc(MF->getFunction()->getContext());
1498 FnStartDL.getLine(), FnStartDL.getCol(),
1499 FnStartDL.getScope(MF->getFunction()->getContext()),
1500 // We'd like to list the prologue as "not statements" but GDB behaves
1501 // poorly if we do that. Revisit this with caution/GDB (7.5+) testing.
1502 DWARF2_FLAG_IS_STMT);
1506 void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) {
1507 if (addCurrentFnArgument(Var, LS))
1509 SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS];
1510 DIVariable DV = Var->getVariable();
1511 // Variables with positive arg numbers are parameters.
1512 if (unsigned ArgNum = DV.getArgNumber()) {
1513 // Keep all parameters in order at the start of the variable list to ensure
1514 // function types are correct (no out-of-order parameters)
1516 // This could be improved by only doing it for optimized builds (unoptimized
1517 // builds have the right order to begin with), searching from the back (this
1518 // would catch the unoptimized case quickly), or doing a binary search
1519 // rather than linear search.
1520 SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin();
1521 while (I != Vars.end()) {
1522 unsigned CurNum = (*I)->getVariable().getArgNumber();
1523 // A local (non-parameter) variable has been found, insert immediately
1527 // A later indexed parameter has been found, insert immediately before it.
1528 if (CurNum > ArgNum)
1532 Vars.insert(I, Var);
1536 Vars.push_back(Var);
1539 // Gather and emit post-function debug information.
1540 void DwarfDebug::endFunction(const MachineFunction *MF) {
1541 // Every beginFunction(MF) call should be followed by an endFunction(MF) call,
1542 // though the beginFunction may not be called at all.
1543 // We should handle both cases.
1547 assert(CurFn == MF);
1548 assert(CurFn != nullptr);
1550 if (!MMI->hasDebugInfo() || LScopes.empty() ||
1551 !FunctionDIs.count(MF->getFunction())) {
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 assert(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 assert(DV && DV.isVariable());
1584 if (!ProcessedVars.insert(DV))
1586 ensureAbstractVariableIsCreated(DV, DV.getContext());
1588 constructAbstractSubprogramScopeDIE(TheCU, AScope);
1591 DIE &CurFnDIE = constructSubprogramScopeDIE(TheCU, FnScope);
1592 if (!CurFn->getTarget().Options.DisableFramePointerElim(*CurFn))
1593 TheCU.addFlag(CurFnDIE, dwarf::DW_AT_APPLE_omit_frame_ptr);
1595 // Add the range of this function to the list of ranges for the CU.
1596 RangeSpan Span(FunctionBeginSym, FunctionEndSym);
1597 TheCU.addRange(std::move(Span));
1598 PrevSection = Asm->getCurrentSection();
1602 // Ownership of DbgVariables is a bit subtle - ScopeVariables owns all the
1603 // DbgVariables except those that are also in AbstractVariables (since they
1604 // can be used cross-function)
1605 ScopeVariables.clear();
1606 CurrentFnArguments.clear();
1608 LabelsBeforeInsn.clear();
1609 LabelsAfterInsn.clear();
1610 PrevLabel = nullptr;
1614 // Register a source line with debug info. Returns the unique label that was
1615 // emitted and which provides correspondence to the source line list.
1616 void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S,
1621 unsigned Discriminator = 0;
1622 if (DIScope Scope = DIScope(S)) {
1623 assert(Scope.isScope());
1624 Fn = Scope.getFilename();
1625 Dir = Scope.getDirectory();
1626 if (Scope.isLexicalBlock())
1627 Discriminator = DILexicalBlock(S).getDiscriminator();
1629 unsigned CUID = Asm->OutStreamer.getContext().getDwarfCompileUnitID();
1630 Src = static_cast<DwarfCompileUnit &>(*InfoHolder.getUnits()[CUID])
1631 .getOrCreateSourceID(Fn, Dir);
1633 Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0,
1637 //===----------------------------------------------------------------------===//
1639 //===----------------------------------------------------------------------===//
1641 // Emit initial Dwarf sections with a label at the start of each one.
1642 void DwarfDebug::emitSectionLabels() {
1643 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
1645 // Dwarf sections base addresses.
1646 DwarfInfoSectionSym =
1647 emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info");
1648 if (useSplitDwarf()) {
1649 DwarfInfoDWOSectionSym =
1650 emitSectionSym(Asm, TLOF.getDwarfInfoDWOSection(), "section_info_dwo");
1651 DwarfTypesDWOSectionSym =
1652 emitSectionSym(Asm, TLOF.getDwarfTypesDWOSection(), "section_types_dwo");
1654 DwarfAbbrevSectionSym =
1655 emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev");
1656 if (useSplitDwarf())
1657 DwarfAbbrevDWOSectionSym = emitSectionSym(
1658 Asm, TLOF.getDwarfAbbrevDWOSection(), "section_abbrev_dwo");
1659 if (GenerateARangeSection)
1660 emitSectionSym(Asm, TLOF.getDwarfARangesSection());
1662 DwarfLineSectionSym =
1663 emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line");
1664 if (GenerateGnuPubSections) {
1665 DwarfGnuPubNamesSectionSym =
1666 emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection());
1667 DwarfGnuPubTypesSectionSym =
1668 emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection());
1669 } else if (HasDwarfPubSections) {
1670 emitSectionSym(Asm, TLOF.getDwarfPubNamesSection());
1671 emitSectionSym(Asm, TLOF.getDwarfPubTypesSection());
1674 DwarfStrSectionSym =
1675 emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string");
1676 if (useSplitDwarf()) {
1677 DwarfStrDWOSectionSym =
1678 emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string");
1679 DwarfAddrSectionSym =
1680 emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec");
1681 DwarfDebugLocSectionSym =
1682 emitSectionSym(Asm, TLOF.getDwarfLocDWOSection(), "skel_loc");
1684 DwarfDebugLocSectionSym =
1685 emitSectionSym(Asm, TLOF.getDwarfLocSection(), "section_debug_loc");
1686 DwarfDebugRangeSectionSym =
1687 emitSectionSym(Asm, TLOF.getDwarfRangesSection(), "debug_range");
1690 // Recursively emits a debug information entry.
1691 void DwarfDebug::emitDIE(DIE &Die) {
1692 // Get the abbreviation for this DIE.
1693 const DIEAbbrev &Abbrev = Die.getAbbrev();
1695 // Emit the code (index) for the abbreviation.
1696 if (Asm->isVerbose())
1697 Asm->OutStreamer.AddComment("Abbrev [" + Twine(Abbrev.getNumber()) +
1698 "] 0x" + Twine::utohexstr(Die.getOffset()) +
1699 ":0x" + Twine::utohexstr(Die.getSize()) + " " +
1700 dwarf::TagString(Abbrev.getTag()));
1701 Asm->EmitULEB128(Abbrev.getNumber());
1703 const SmallVectorImpl<DIEValue *> &Values = Die.getValues();
1704 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
1706 // Emit the DIE attribute values.
1707 for (unsigned i = 0, N = Values.size(); i < N; ++i) {
1708 dwarf::Attribute Attr = AbbrevData[i].getAttribute();
1709 dwarf::Form Form = AbbrevData[i].getForm();
1710 assert(Form && "Too many attributes for DIE (check abbreviation)");
1712 if (Asm->isVerbose()) {
1713 Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr));
1714 if (Attr == dwarf::DW_AT_accessibility)
1715 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(
1716 cast<DIEInteger>(Values[i])->getValue()));
1719 // Emit an attribute using the defined form.
1720 Values[i]->EmitValue(Asm, Form);
1723 // Emit the DIE children if any.
1724 if (Abbrev.hasChildren()) {
1725 for (auto &Child : Die.getChildren())
1728 Asm->OutStreamer.AddComment("End Of Children Mark");
1733 // Emit the debug info section.
1734 void DwarfDebug::emitDebugInfo() {
1735 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1737 Holder.emitUnits(this, DwarfAbbrevSectionSym);
1740 // Emit the abbreviation section.
1741 void DwarfDebug::emitAbbreviations() {
1742 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1744 Holder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection());
1747 // Emit the last address of the section and the end of the line matrix.
1748 void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) {
1749 // Define last address of section.
1750 Asm->OutStreamer.AddComment("Extended Op");
1753 Asm->OutStreamer.AddComment("Op size");
1754 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1);
1755 Asm->OutStreamer.AddComment("DW_LNE_set_address");
1756 Asm->EmitInt8(dwarf::DW_LNE_set_address);
1758 Asm->OutStreamer.AddComment("Section end label");
1760 Asm->OutStreamer.EmitSymbolValue(
1761 Asm->GetTempSymbol("section_end", SectionEnd),
1762 Asm->getDataLayout().getPointerSize());
1764 // Mark end of matrix.
1765 Asm->OutStreamer.AddComment("DW_LNE_end_sequence");
1771 // Emit visible names into a hashed accelerator table section.
1772 void DwarfDebug::emitAccelNames() {
1773 AccelNames.FinalizeTable(Asm, "Names");
1774 Asm->OutStreamer.SwitchSection(
1775 Asm->getObjFileLowering().getDwarfAccelNamesSection());
1776 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin");
1777 Asm->OutStreamer.EmitLabel(SectionBegin);
1779 // Emit the full data.
1780 AccelNames.Emit(Asm, SectionBegin, &InfoHolder);
1783 // Emit objective C classes and categories into a hashed accelerator table
1785 void DwarfDebug::emitAccelObjC() {
1786 AccelObjC.FinalizeTable(Asm, "ObjC");
1787 Asm->OutStreamer.SwitchSection(
1788 Asm->getObjFileLowering().getDwarfAccelObjCSection());
1789 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin");
1790 Asm->OutStreamer.EmitLabel(SectionBegin);
1792 // Emit the full data.
1793 AccelObjC.Emit(Asm, SectionBegin, &InfoHolder);
1796 // Emit namespace dies into a hashed accelerator table.
1797 void DwarfDebug::emitAccelNamespaces() {
1798 AccelNamespace.FinalizeTable(Asm, "namespac");
1799 Asm->OutStreamer.SwitchSection(
1800 Asm->getObjFileLowering().getDwarfAccelNamespaceSection());
1801 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin");
1802 Asm->OutStreamer.EmitLabel(SectionBegin);
1804 // Emit the full data.
1805 AccelNamespace.Emit(Asm, SectionBegin, &InfoHolder);
1808 // Emit type dies into a hashed accelerator table.
1809 void DwarfDebug::emitAccelTypes() {
1811 AccelTypes.FinalizeTable(Asm, "types");
1812 Asm->OutStreamer.SwitchSection(
1813 Asm->getObjFileLowering().getDwarfAccelTypesSection());
1814 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin");
1815 Asm->OutStreamer.EmitLabel(SectionBegin);
1817 // Emit the full data.
1818 AccelTypes.Emit(Asm, SectionBegin, &InfoHolder);
1821 // Public name handling.
1822 // The format for the various pubnames:
1824 // dwarf pubnames - offset/name pairs where the offset is the offset into the CU
1825 // for the DIE that is named.
1827 // gnu pubnames - offset/index value/name tuples where the offset is the offset
1828 // into the CU and the index value is computed according to the type of value
1829 // for the DIE that is named.
1831 // For type units the offset is the offset of the skeleton DIE. For split dwarf
1832 // it's the offset within the debug_info/debug_types dwo section, however, the
1833 // reference in the pubname header doesn't change.
1835 /// computeIndexValue - Compute the gdb index value for the DIE and CU.
1836 static dwarf::PubIndexEntryDescriptor computeIndexValue(DwarfUnit *CU,
1838 dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC;
1840 // We could have a specification DIE that has our most of our knowledge,
1841 // look for that now.
1842 DIEValue *SpecVal = Die->findAttribute(dwarf::DW_AT_specification);
1844 DIE &SpecDIE = cast<DIEEntry>(SpecVal)->getEntry();
1845 if (SpecDIE.findAttribute(dwarf::DW_AT_external))
1846 Linkage = dwarf::GIEL_EXTERNAL;
1847 } else if (Die->findAttribute(dwarf::DW_AT_external))
1848 Linkage = dwarf::GIEL_EXTERNAL;
1850 switch (Die->getTag()) {
1851 case dwarf::DW_TAG_class_type:
1852 case dwarf::DW_TAG_structure_type:
1853 case dwarf::DW_TAG_union_type:
1854 case dwarf::DW_TAG_enumeration_type:
1855 return dwarf::PubIndexEntryDescriptor(
1856 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus
1857 ? dwarf::GIEL_STATIC
1858 : dwarf::GIEL_EXTERNAL);
1859 case dwarf::DW_TAG_typedef:
1860 case dwarf::DW_TAG_base_type:
1861 case dwarf::DW_TAG_subrange_type:
1862 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC);
1863 case dwarf::DW_TAG_namespace:
1864 return dwarf::GIEK_TYPE;
1865 case dwarf::DW_TAG_subprogram:
1866 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage);
1867 case dwarf::DW_TAG_constant:
1868 case dwarf::DW_TAG_variable:
1869 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage);
1870 case dwarf::DW_TAG_enumerator:
1871 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE,
1872 dwarf::GIEL_STATIC);
1874 return dwarf::GIEK_NONE;
1878 /// emitDebugPubNames - Emit visible names into a debug pubnames section.
1880 void DwarfDebug::emitDebugPubNames(bool GnuStyle) {
1881 const MCSection *PSec =
1882 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection()
1883 : Asm->getObjFileLowering().getDwarfPubNamesSection();
1885 emitDebugPubSection(GnuStyle, PSec, "Names", &DwarfUnit::getGlobalNames);
1888 void DwarfDebug::emitDebugPubSection(
1889 bool GnuStyle, const MCSection *PSec, StringRef Name,
1890 const StringMap<const DIE *> &(DwarfUnit::*Accessor)() const) {
1891 for (const auto &NU : CUMap) {
1892 DwarfCompileUnit *TheU = NU.second;
1894 const auto &Globals = (TheU->*Accessor)();
1896 if (Globals.empty())
1899 if (auto Skeleton = static_cast<DwarfCompileUnit *>(TheU->getSkeleton()))
1901 unsigned ID = TheU->getUniqueID();
1903 // Start the dwarf pubnames section.
1904 Asm->OutStreamer.SwitchSection(PSec);
1907 Asm->OutStreamer.AddComment("Length of Public " + Name + " Info");
1908 MCSymbol *BeginLabel = Asm->GetTempSymbol("pub" + Name + "_begin", ID);
1909 MCSymbol *EndLabel = Asm->GetTempSymbol("pub" + Name + "_end", ID);
1910 Asm->EmitLabelDifference(EndLabel, BeginLabel, 4);
1912 Asm->OutStreamer.EmitLabel(BeginLabel);
1914 Asm->OutStreamer.AddComment("DWARF Version");
1915 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION);
1917 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info");
1918 Asm->EmitSectionOffset(TheU->getLabelBegin(), TheU->getSectionSym());
1920 Asm->OutStreamer.AddComment("Compilation Unit Length");
1921 Asm->EmitLabelDifference(TheU->getLabelEnd(), TheU->getLabelBegin(), 4);
1923 // Emit the pubnames for this compilation unit.
1924 for (const auto &GI : Globals) {
1925 const char *Name = GI.getKeyData();
1926 const DIE *Entity = GI.second;
1928 Asm->OutStreamer.AddComment("DIE offset");
1929 Asm->EmitInt32(Entity->getOffset());
1932 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheU, Entity);
1933 Asm->OutStreamer.AddComment(
1934 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " +
1935 dwarf::GDBIndexEntryLinkageString(Desc.Linkage));
1936 Asm->EmitInt8(Desc.toBits());
1939 Asm->OutStreamer.AddComment("External Name");
1940 Asm->OutStreamer.EmitBytes(StringRef(Name, GI.getKeyLength() + 1));
1943 Asm->OutStreamer.AddComment("End Mark");
1945 Asm->OutStreamer.EmitLabel(EndLabel);
1949 void DwarfDebug::emitDebugPubTypes(bool GnuStyle) {
1950 const MCSection *PSec =
1951 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection()
1952 : Asm->getObjFileLowering().getDwarfPubTypesSection();
1954 emitDebugPubSection(GnuStyle, PSec, "Types", &DwarfUnit::getGlobalTypes);
1957 // Emit visible names into a debug str section.
1958 void DwarfDebug::emitDebugStr() {
1959 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1960 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection());
1963 void DwarfDebug::emitDebugLocEntry(ByteStreamer &Streamer,
1964 const DebugLocEntry &Entry) {
1965 assert(Entry.getValues().size() == 1 &&
1966 "multi-value entries are not supported yet.");
1967 const DebugLocEntry::Value Value = Entry.getValues()[0];
1968 DIVariable DV(Value.getVariable());
1969 if (Value.isInt()) {
1970 DIBasicType BTy(resolve(DV.getType()));
1971 if (BTy.Verify() && (BTy.getEncoding() == dwarf::DW_ATE_signed ||
1972 BTy.getEncoding() == dwarf::DW_ATE_signed_char)) {
1973 Streamer.EmitInt8(dwarf::DW_OP_consts, "DW_OP_consts");
1974 Streamer.EmitSLEB128(Value.getInt());
1976 Streamer.EmitInt8(dwarf::DW_OP_constu, "DW_OP_constu");
1977 Streamer.EmitULEB128(Value.getInt());
1979 } else if (Value.isLocation()) {
1980 MachineLocation Loc = Value.getLoc();
1981 if (!DV.hasComplexAddress())
1983 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
1985 // Complex address entry.
1986 unsigned N = DV.getNumAddrElements();
1988 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) {
1989 if (Loc.getOffset()) {
1991 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
1992 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
1993 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
1994 Streamer.EmitSLEB128(DV.getAddrElement(1));
1996 // If first address element is OpPlus then emit
1997 // DW_OP_breg + Offset instead of DW_OP_reg + Offset.
1998 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1));
1999 Asm->EmitDwarfRegOp(Streamer, TLoc, DV.isIndirect());
2003 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2006 // Emit remaining complex address elements.
2007 for (; i < N; ++i) {
2008 uint64_t Element = DV.getAddrElement(i);
2009 if (Element == DIBuilder::OpPlus) {
2010 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
2011 Streamer.EmitULEB128(DV.getAddrElement(++i));
2012 } else if (Element == DIBuilder::OpDeref) {
2014 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
2016 llvm_unreachable("unknown Opcode found in complex address");
2020 // else ... ignore constant fp. There is not any good way to
2021 // to represent them here in dwarf.
2025 void DwarfDebug::emitDebugLocEntryLocation(const DebugLocEntry &Entry) {
2026 Asm->OutStreamer.AddComment("Loc expr size");
2027 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol();
2028 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol();
2029 Asm->EmitLabelDifference(end, begin, 2);
2030 Asm->OutStreamer.EmitLabel(begin);
2032 APByteStreamer Streamer(*Asm);
2033 emitDebugLocEntry(Streamer, Entry);
2035 Asm->OutStreamer.EmitLabel(end);
2038 // Emit locations into the debug loc section.
2039 void DwarfDebug::emitDebugLoc() {
2040 // Start the dwarf loc section.
2041 Asm->OutStreamer.SwitchSection(
2042 Asm->getObjFileLowering().getDwarfLocSection());
2043 unsigned char Size = Asm->getDataLayout().getPointerSize();
2044 for (const auto &DebugLoc : DotDebugLocEntries) {
2045 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2046 for (const auto &Entry : DebugLoc.List) {
2047 // Set up the range. This range is relative to the entry point of the
2048 // compile unit. This is a hard coded 0 for low_pc when we're emitting
2049 // ranges, or the DW_AT_low_pc on the compile unit otherwise.
2050 const DwarfCompileUnit *CU = Entry.getCU();
2051 if (CU->getRanges().size() == 1) {
2052 // Grab the begin symbol from the first range as our base.
2053 const MCSymbol *Base = CU->getRanges()[0].getStart();
2054 Asm->EmitLabelDifference(Entry.getBeginSym(), Base, Size);
2055 Asm->EmitLabelDifference(Entry.getEndSym(), Base, Size);
2057 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size);
2058 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size);
2061 emitDebugLocEntryLocation(Entry);
2063 Asm->OutStreamer.EmitIntValue(0, Size);
2064 Asm->OutStreamer.EmitIntValue(0, Size);
2068 void DwarfDebug::emitDebugLocDWO() {
2069 Asm->OutStreamer.SwitchSection(
2070 Asm->getObjFileLowering().getDwarfLocDWOSection());
2071 for (const auto &DebugLoc : DotDebugLocEntries) {
2072 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2073 for (const auto &Entry : DebugLoc.List) {
2074 // Just always use start_length for now - at least that's one address
2075 // rather than two. We could get fancier and try to, say, reuse an
2076 // address we know we've emitted elsewhere (the start of the function?
2077 // The start of the CU or CU subrange that encloses this range?)
2078 Asm->EmitInt8(dwarf::DW_LLE_start_length_entry);
2079 unsigned idx = AddrPool.getIndex(Entry.getBeginSym());
2080 Asm->EmitULEB128(idx);
2081 Asm->EmitLabelDifference(Entry.getEndSym(), Entry.getBeginSym(), 4);
2083 emitDebugLocEntryLocation(Entry);
2085 Asm->EmitInt8(dwarf::DW_LLE_end_of_list_entry);
2090 const MCSymbol *Start, *End;
2093 // Emit a debug aranges section, containing a CU lookup for any
2094 // address we can tie back to a CU.
2095 void DwarfDebug::emitDebugARanges() {
2096 // Start the dwarf aranges section.
2097 Asm->OutStreamer.SwitchSection(
2098 Asm->getObjFileLowering().getDwarfARangesSection());
2100 typedef DenseMap<DwarfCompileUnit *, std::vector<ArangeSpan>> SpansType;
2104 // Build a list of sections used.
2105 std::vector<const MCSection *> Sections;
2106 for (const auto &it : SectionMap) {
2107 const MCSection *Section = it.first;
2108 Sections.push_back(Section);
2111 // Sort the sections into order.
2112 // This is only done to ensure consistent output order across different runs.
2113 std::sort(Sections.begin(), Sections.end(), SectionSort);
2115 // Build a set of address spans, sorted by CU.
2116 for (const MCSection *Section : Sections) {
2117 SmallVector<SymbolCU, 8> &List = SectionMap[Section];
2118 if (List.size() < 2)
2121 // Sort the symbols by offset within the section.
2122 std::sort(List.begin(), List.end(),
2123 [&](const SymbolCU &A, const SymbolCU &B) {
2124 unsigned IA = A.Sym ? Asm->OutStreamer.GetSymbolOrder(A.Sym) : 0;
2125 unsigned IB = B.Sym ? Asm->OutStreamer.GetSymbolOrder(B.Sym) : 0;
2127 // Symbols with no order assigned should be placed at the end.
2128 // (e.g. section end labels)
2136 // If we have no section (e.g. common), just write out
2137 // individual spans for each symbol.
2139 for (const SymbolCU &Cur : List) {
2141 Span.Start = Cur.Sym;
2144 Spans[Cur.CU].push_back(Span);
2147 // Build spans between each label.
2148 const MCSymbol *StartSym = List[0].Sym;
2149 for (size_t n = 1, e = List.size(); n < e; n++) {
2150 const SymbolCU &Prev = List[n - 1];
2151 const SymbolCU &Cur = List[n];
2153 // Try and build the longest span we can within the same CU.
2154 if (Cur.CU != Prev.CU) {
2156 Span.Start = StartSym;
2158 Spans[Prev.CU].push_back(Span);
2165 unsigned PtrSize = Asm->getDataLayout().getPointerSize();
2167 // Build a list of CUs used.
2168 std::vector<DwarfCompileUnit *> CUs;
2169 for (const auto &it : Spans) {
2170 DwarfCompileUnit *CU = it.first;
2174 // Sort the CU list (again, to ensure consistent output order).
2175 std::sort(CUs.begin(), CUs.end(), [](const DwarfUnit *A, const DwarfUnit *B) {
2176 return A->getUniqueID() < B->getUniqueID();
2179 // Emit an arange table for each CU we used.
2180 for (DwarfCompileUnit *CU : CUs) {
2181 std::vector<ArangeSpan> &List = Spans[CU];
2183 // Emit size of content not including length itself.
2184 unsigned ContentSize =
2185 sizeof(int16_t) + // DWARF ARange version number
2186 sizeof(int32_t) + // Offset of CU in the .debug_info section
2187 sizeof(int8_t) + // Pointer Size (in bytes)
2188 sizeof(int8_t); // Segment Size (in bytes)
2190 unsigned TupleSize = PtrSize * 2;
2192 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple.
2194 OffsetToAlignment(sizeof(int32_t) + ContentSize, TupleSize);
2196 ContentSize += Padding;
2197 ContentSize += (List.size() + 1) * TupleSize;
2199 // For each compile unit, write the list of spans it covers.
2200 Asm->OutStreamer.AddComment("Length of ARange Set");
2201 Asm->EmitInt32(ContentSize);
2202 Asm->OutStreamer.AddComment("DWARF Arange version number");
2203 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION);
2204 Asm->OutStreamer.AddComment("Offset Into Debug Info Section");
2205 Asm->EmitSectionOffset(CU->getLocalLabelBegin(), CU->getLocalSectionSym());
2206 Asm->OutStreamer.AddComment("Address Size (in bytes)");
2207 Asm->EmitInt8(PtrSize);
2208 Asm->OutStreamer.AddComment("Segment Size (in bytes)");
2211 Asm->OutStreamer.EmitFill(Padding, 0xff);
2213 for (const ArangeSpan &Span : List) {
2214 Asm->EmitLabelReference(Span.Start, PtrSize);
2216 // Calculate the size as being from the span start to it's end.
2218 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize);
2220 // For symbols without an end marker (e.g. common), we
2221 // write a single arange entry containing just that one symbol.
2222 uint64_t Size = SymSize[Span.Start];
2226 Asm->OutStreamer.EmitIntValue(Size, PtrSize);
2230 Asm->OutStreamer.AddComment("ARange terminator");
2231 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2232 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2236 // Emit visible names into a debug ranges section.
2237 void DwarfDebug::emitDebugRanges() {
2238 // Start the dwarf ranges section.
2239 Asm->OutStreamer.SwitchSection(
2240 Asm->getObjFileLowering().getDwarfRangesSection());
2242 // Size for our labels.
2243 unsigned char Size = Asm->getDataLayout().getPointerSize();
2245 // Grab the specific ranges for the compile units in the module.
2246 for (const auto &I : CUMap) {
2247 DwarfCompileUnit *TheCU = I.second;
2249 // Iterate over the misc ranges for the compile units in the module.
2250 for (const RangeSpanList &List : TheCU->getRangeLists()) {
2251 // Emit our symbol so we can find the beginning of the range.
2252 Asm->OutStreamer.EmitLabel(List.getSym());
2254 for (const RangeSpan &Range : List.getRanges()) {
2255 const MCSymbol *Begin = Range.getStart();
2256 const MCSymbol *End = Range.getEnd();
2257 assert(Begin && "Range without a begin symbol?");
2258 assert(End && "Range without an end symbol?");
2259 if (TheCU->getRanges().size() == 1) {
2260 // Grab the begin symbol from the first range as our base.
2261 const MCSymbol *Base = TheCU->getRanges()[0].getStart();
2262 Asm->EmitLabelDifference(Begin, Base, Size);
2263 Asm->EmitLabelDifference(End, Base, Size);
2265 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2266 Asm->OutStreamer.EmitSymbolValue(End, Size);
2270 // And terminate the list with two 0 values.
2271 Asm->OutStreamer.EmitIntValue(0, Size);
2272 Asm->OutStreamer.EmitIntValue(0, Size);
2275 // Now emit a range for the CU itself.
2276 if (TheCU->getRanges().size() > 1) {
2277 Asm->OutStreamer.EmitLabel(
2278 Asm->GetTempSymbol("cu_ranges", TheCU->getUniqueID()));
2279 for (const RangeSpan &Range : TheCU->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 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2285 Asm->OutStreamer.EmitSymbolValue(End, Size);
2287 // And terminate the list with two 0 values.
2288 Asm->OutStreamer.EmitIntValue(0, Size);
2289 Asm->OutStreamer.EmitIntValue(0, Size);
2294 // DWARF5 Experimental Separate Dwarf emitters.
2296 void DwarfDebug::initSkeletonUnit(const DwarfUnit &U, DIE &Die,
2297 std::unique_ptr<DwarfUnit> NewU) {
2298 NewU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name,
2299 U.getCUNode().getSplitDebugFilename());
2301 if (!CompilationDir.empty())
2302 NewU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
2304 addGnuPubAttributes(*NewU, Die);
2306 SkeletonHolder.addUnit(std::move(NewU));
2309 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list,
2310 // DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id,
2311 // DW_AT_addr_base, DW_AT_ranges_base.
2312 DwarfCompileUnit &DwarfDebug::constructSkeletonCU(const DwarfCompileUnit &CU) {
2314 auto OwnedUnit = make_unique<DwarfCompileUnit>(
2315 CU.getUniqueID(), CU.getCUNode(), Asm, this, &SkeletonHolder);
2316 DwarfCompileUnit &NewCU = *OwnedUnit;
2317 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
2318 DwarfInfoSectionSym);
2320 NewCU.initStmtList(DwarfLineSectionSym);
2322 initSkeletonUnit(CU, NewCU.getUnitDie(), std::move(OwnedUnit));
2327 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_dwo_name,
2329 DwarfTypeUnit &DwarfDebug::constructSkeletonTU(DwarfTypeUnit &TU) {
2330 DwarfCompileUnit &CU = static_cast<DwarfCompileUnit &>(
2331 *SkeletonHolder.getUnits()[TU.getCU().getUniqueID()]);
2333 auto OwnedUnit = make_unique<DwarfTypeUnit>(TU.getUniqueID(), CU, Asm, this,
2335 DwarfTypeUnit &NewTU = *OwnedUnit;
2336 NewTU.setTypeSignature(TU.getTypeSignature());
2337 NewTU.setType(nullptr);
2339 Asm->getObjFileLowering().getDwarfTypesSection(TU.getTypeSignature()));
2341 initSkeletonUnit(TU, NewTU.getUnitDie(), std::move(OwnedUnit));
2345 // Emit the .debug_info.dwo section for separated dwarf. This contains the
2346 // compile units that would normally be in debug_info.
2347 void DwarfDebug::emitDebugInfoDWO() {
2348 assert(useSplitDwarf() && "No split dwarf debug info?");
2349 // Don't pass an abbrev symbol, using a constant zero instead so as not to
2350 // emit relocations into the dwo file.
2351 InfoHolder.emitUnits(this, /* AbbrevSymbol */ nullptr);
2354 // Emit the .debug_abbrev.dwo section for separated dwarf. This contains the
2355 // abbreviations for the .debug_info.dwo section.
2356 void DwarfDebug::emitDebugAbbrevDWO() {
2357 assert(useSplitDwarf() && "No split dwarf?");
2358 InfoHolder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection());
2361 void DwarfDebug::emitDebugLineDWO() {
2362 assert(useSplitDwarf() && "No split dwarf?");
2363 Asm->OutStreamer.SwitchSection(
2364 Asm->getObjFileLowering().getDwarfLineDWOSection());
2365 SplitTypeUnitFileTable.Emit(Asm->OutStreamer);
2368 // Emit the .debug_str.dwo section for separated dwarf. This contains the
2369 // string section and is identical in format to traditional .debug_str
2371 void DwarfDebug::emitDebugStrDWO() {
2372 assert(useSplitDwarf() && "No split dwarf?");
2373 const MCSection *OffSec =
2374 Asm->getObjFileLowering().getDwarfStrOffDWOSection();
2375 const MCSymbol *StrSym = DwarfStrSectionSym;
2376 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(),
2380 MCDwarfDwoLineTable *DwarfDebug::getDwoLineTable(const DwarfCompileUnit &CU) {
2381 if (!useSplitDwarf())
2384 SplitTypeUnitFileTable.setCompilationDir(CU.getCUNode().getDirectory());
2385 return &SplitTypeUnitFileTable;
2388 static uint64_t makeTypeSignature(StringRef Identifier) {
2390 Hash.update(Identifier);
2391 // ... take the least significant 8 bytes and return those. Our MD5
2392 // implementation always returns its results in little endian, swap bytes
2394 MD5::MD5Result Result;
2396 return *reinterpret_cast<support::ulittle64_t *>(Result + 8);
2399 void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU,
2400 StringRef Identifier, DIE &RefDie,
2401 DICompositeType CTy) {
2402 // Fast path if we're building some type units and one has already used the
2403 // address pool we know we're going to throw away all this work anyway, so
2404 // don't bother building dependent types.
2405 if (!TypeUnitsUnderConstruction.empty() && AddrPool.hasBeenUsed())
2408 const DwarfTypeUnit *&TU = DwarfTypeUnits[CTy];
2410 CU.addDIETypeSignature(RefDie, *TU);
2414 bool TopLevelType = TypeUnitsUnderConstruction.empty();
2415 AddrPool.resetUsedFlag();
2417 auto OwnedUnit = make_unique<DwarfTypeUnit>(
2418 InfoHolder.getUnits().size() + TypeUnitsUnderConstruction.size(), CU, Asm,
2419 this, &InfoHolder, getDwoLineTable(CU));
2420 DwarfTypeUnit &NewTU = *OwnedUnit;
2421 DIE &UnitDie = NewTU.getUnitDie();
2423 TypeUnitsUnderConstruction.push_back(
2424 std::make_pair(std::move(OwnedUnit), CTy));
2426 NewTU.addUInt(UnitDie, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
2429 uint64_t Signature = makeTypeSignature(Identifier);
2430 NewTU.setTypeSignature(Signature);
2432 if (useSplitDwarf())
2433 NewTU.initSection(Asm->getObjFileLowering().getDwarfTypesDWOSection(),
2434 DwarfTypesDWOSectionSym);
2436 CU.applyStmtList(UnitDie);
2438 Asm->getObjFileLowering().getDwarfTypesSection(Signature));
2441 NewTU.setType(NewTU.createTypeDIE(CTy));
2444 auto TypeUnitsToAdd = std::move(TypeUnitsUnderConstruction);
2445 TypeUnitsUnderConstruction.clear();
2447 // Types referencing entries in the address table cannot be placed in type
2449 if (AddrPool.hasBeenUsed()) {
2451 // Remove all the types built while building this type.
2452 // This is pessimistic as some of these types might not be dependent on
2453 // the type that used an address.
2454 for (const auto &TU : TypeUnitsToAdd)
2455 DwarfTypeUnits.erase(TU.second);
2457 // Construct this type in the CU directly.
2458 // This is inefficient because all the dependent types will be rebuilt
2459 // from scratch, including building them in type units, discovering that
2460 // they depend on addresses, throwing them out and rebuilding them.
2461 CU.constructTypeDIE(RefDie, CTy);
2465 // If the type wasn't dependent on fission addresses, finish adding the type
2466 // and all its dependent types.
2467 for (auto &TU : TypeUnitsToAdd) {
2468 if (useSplitDwarf())
2469 TU.first->setSkeleton(constructSkeletonTU(*TU.first));
2470 InfoHolder.addUnit(std::move(TU.first));
2473 CU.addDIETypeSignature(RefDie, NewTU);
2476 void DwarfDebug::attachLowHighPC(DwarfCompileUnit &Unit, DIE &D,
2477 MCSymbol *Begin, MCSymbol *End) {
2478 assert(Begin && "Begin label should not be null!");
2479 assert(End && "End label should not be null!");
2480 assert(Begin->isDefined() && "Invalid starting label");
2481 assert(End->isDefined() && "Invalid end label");
2483 Unit.addLabelAddress(D, dwarf::DW_AT_low_pc, Begin);
2484 if (DwarfVersion < 4)
2485 Unit.addLabelAddress(D, dwarf::DW_AT_high_pc, End);
2487 Unit.addLabelDelta(D, dwarf::DW_AT_high_pc, End, Begin);
2490 // Accelerator table mutators - add each name along with its companion
2491 // DIE to the proper table while ensuring that the name that we're going
2492 // to reference is in the string table. We do this since the names we
2493 // add may not only be identical to the names in the DIE.
2494 void DwarfDebug::addAccelName(StringRef Name, const DIE &Die) {
2495 if (!useDwarfAccelTables())
2497 AccelNames.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2501 void DwarfDebug::addAccelObjC(StringRef Name, const DIE &Die) {
2502 if (!useDwarfAccelTables())
2504 AccelObjC.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2508 void DwarfDebug::addAccelNamespace(StringRef Name, const DIE &Die) {
2509 if (!useDwarfAccelTables())
2511 AccelNamespace.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2515 void DwarfDebug::addAccelType(StringRef Name, const DIE &Die, char Flags) {
2516 if (!useDwarfAccelTables())
2518 AccelTypes.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),