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).getTypeArray();
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 DIArray FnArgs = SP.getType().getTypeArray();
472 if (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 CU.getOrCreateTypeDIE(EnumTypes.getElement(i));
767 DIArray RetainedTypes = CUNode.getRetainedTypes();
768 for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i) {
769 DIType Ty(RetainedTypes.getElement(i));
770 // The retained types array by design contains pointers to
771 // MDNodes rather than DIRefs. Unique them here.
772 DIType UniqueTy(resolve(Ty.getRef()));
773 CU.getOrCreateTypeDIE(UniqueTy);
775 // Emit imported_modules last so that the relevant context is already
777 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
778 constructImportedEntityDIE(CU, ImportedEntities.getElement(i));
781 // Tell MMI that we have debug info.
782 MMI->setDebugInfoAvailability(true);
784 // Prime section data.
785 SectionMap[Asm->getObjFileLowering().getTextSection()];
788 void DwarfDebug::finishVariableDefinitions() {
789 for (const auto &Var : ConcreteVariables) {
790 DIE *VariableDie = Var->getDIE();
791 // FIXME: There shouldn't be any variables without DIEs.
794 // FIXME: Consider the time-space tradeoff of just storing the unit pointer
795 // in the ConcreteVariables list, rather than looking it up again here.
796 // DIE::getUnit isn't simple - it walks parent pointers, etc.
797 DwarfCompileUnit *Unit = lookupUnit(VariableDie->getUnit());
799 DbgVariable *AbsVar = getExistingAbstractVariable(Var->getVariable());
800 if (AbsVar && AbsVar->getDIE()) {
801 Unit->addDIEEntry(*VariableDie, dwarf::DW_AT_abstract_origin,
804 Unit->applyVariableAttributes(*Var, *VariableDie);
808 void DwarfDebug::finishSubprogramDefinitions() {
809 const Module *M = MMI->getModule();
811 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
812 for (MDNode *N : CU_Nodes->operands()) {
813 DICompileUnit TheCU(N);
814 // Construct subprogram DIE and add variables DIEs.
815 DwarfCompileUnit *SPCU =
816 static_cast<DwarfCompileUnit *>(CUMap.lookup(TheCU));
817 DIArray Subprograms = TheCU.getSubprograms();
818 for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) {
819 DISubprogram SP(Subprograms.getElement(i));
820 // Perhaps the subprogram is in another CU (such as due to comdat
821 // folding, etc), in which case ignore it here.
822 if (SPMap[SP] != SPCU)
824 DIE *D = SPCU->getDIE(SP);
825 if (DIE *AbsSPDIE = AbstractSPDies.lookup(SP)) {
827 // If this subprogram has an abstract definition, reference that
828 SPCU->addDIEEntry(*D, dwarf::DW_AT_abstract_origin, *AbsSPDIE);
831 // Lazily construct the subprogram if we didn't see either concrete or
832 // inlined versions during codegen.
833 D = SPCU->getOrCreateSubprogramDIE(SP);
834 // And attach the attributes
835 SPCU->applySubprogramAttributesToDefinition(SP, *D);
842 // Collect info for variables that were optimized out.
843 void DwarfDebug::collectDeadVariables() {
844 const Module *M = MMI->getModule();
846 if (NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu")) {
847 for (MDNode *N : CU_Nodes->operands()) {
848 DICompileUnit TheCU(N);
849 // Construct subprogram DIE and add variables DIEs.
850 DwarfCompileUnit *SPCU =
851 static_cast<DwarfCompileUnit *>(CUMap.lookup(TheCU));
852 assert(SPCU && "Unable to find Compile Unit!");
853 DIArray Subprograms = TheCU.getSubprograms();
854 for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) {
855 DISubprogram SP(Subprograms.getElement(i));
856 if (ProcessedSPNodes.count(SP) != 0)
858 assert(SP.isSubprogram() &&
859 "CU's subprogram list contains a non-subprogram");
860 assert(SP.isDefinition() &&
861 "CU's subprogram list contains a subprogram declaration");
862 DIArray Variables = SP.getVariables();
863 if (Variables.getNumElements() == 0)
866 DIE *SPDIE = AbstractSPDies.lookup(SP);
868 SPDIE = SPCU->getDIE(SP);
870 for (unsigned vi = 0, ve = Variables.getNumElements(); vi != ve; ++vi) {
871 DIVariable DV(Variables.getElement(vi));
872 assert(DV.isVariable());
873 DbgVariable NewVar(DV, this);
874 auto VariableDie = SPCU->constructVariableDIE(NewVar);
875 SPCU->applyVariableAttributes(NewVar, *VariableDie);
876 SPDIE->addChild(std::move(VariableDie));
883 void DwarfDebug::finalizeModuleInfo() {
884 finishSubprogramDefinitions();
886 finishVariableDefinitions();
888 // Collect info for variables that were optimized out.
889 collectDeadVariables();
891 // Handle anything that needs to be done on a per-unit basis after
892 // all other generation.
893 for (const auto &TheU : getUnits()) {
894 // Emit DW_AT_containing_type attribute to connect types with their
895 // vtable holding type.
896 TheU->constructContainingTypeDIEs();
898 // Add CU specific attributes if we need to add any.
899 if (TheU->getUnitDie().getTag() == dwarf::DW_TAG_compile_unit) {
900 // If we're splitting the dwarf out now that we've got the entire
901 // CU then add the dwo id to it.
902 DwarfCompileUnit *SkCU =
903 static_cast<DwarfCompileUnit *>(TheU->getSkeleton());
904 if (useSplitDwarf()) {
905 // Emit a unique identifier for this CU.
906 uint64_t ID = DIEHash(Asm).computeCUSignature(TheU->getUnitDie());
907 TheU->addUInt(TheU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
908 dwarf::DW_FORM_data8, ID);
909 SkCU->addUInt(SkCU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
910 dwarf::DW_FORM_data8, ID);
912 // We don't keep track of which addresses are used in which CU so this
913 // is a bit pessimistic under LTO.
914 if (!AddrPool.isEmpty())
915 addSectionLabel(*Asm, *SkCU, SkCU->getUnitDie(),
916 dwarf::DW_AT_GNU_addr_base, DwarfAddrSectionSym,
917 DwarfAddrSectionSym);
918 if (!TheU->getRangeLists().empty())
919 addSectionLabel(*Asm, *SkCU, SkCU->getUnitDie(),
920 dwarf::DW_AT_GNU_ranges_base,
921 DwarfDebugRangeSectionSym, DwarfDebugRangeSectionSym);
924 // If we have code split among multiple sections or non-contiguous
925 // ranges of code then emit a DW_AT_ranges attribute on the unit that will
926 // remain in the .o file, otherwise add a DW_AT_low_pc.
927 // FIXME: We should use ranges allow reordering of code ala
928 // .subsections_via_symbols in mach-o. This would mean turning on
929 // ranges for all subprogram DIEs for mach-o.
930 DwarfCompileUnit &U =
931 SkCU ? *SkCU : static_cast<DwarfCompileUnit &>(*TheU);
932 unsigned NumRanges = TheU->getRanges().size();
935 addSectionLabel(*Asm, U, U.getUnitDie(), dwarf::DW_AT_ranges,
936 Asm->GetTempSymbol("cu_ranges", U.getUniqueID()),
937 DwarfDebugRangeSectionSym);
939 // A DW_AT_low_pc attribute may also be specified in combination with
940 // DW_AT_ranges to specify the default base address for use in
941 // location lists (see Section 2.6.2) and range lists (see Section
943 U.addUInt(U.getUnitDie(), dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr,
946 RangeSpan &Range = TheU->getRanges().back();
947 U.addLocalLabelAddress(U.getUnitDie(), dwarf::DW_AT_low_pc,
949 U.addLabelDelta(U.getUnitDie(), dwarf::DW_AT_high_pc, Range.getEnd(),
956 // Compute DIE offsets and sizes.
957 InfoHolder.computeSizeAndOffsets();
959 SkeletonHolder.computeSizeAndOffsets();
962 void DwarfDebug::endSections() {
963 // Filter labels by section.
964 for (const SymbolCU &SCU : ArangeLabels) {
965 if (SCU.Sym->isInSection()) {
966 // Make a note of this symbol and it's section.
967 const MCSection *Section = &SCU.Sym->getSection();
968 if (!Section->getKind().isMetadata())
969 SectionMap[Section].push_back(SCU);
971 // Some symbols (e.g. common/bss on mach-o) can have no section but still
972 // appear in the output. This sucks as we rely on sections to build
973 // arange spans. We can do it without, but it's icky.
974 SectionMap[nullptr].push_back(SCU);
978 // Build a list of sections used.
979 std::vector<const MCSection *> Sections;
980 for (const auto &it : SectionMap) {
981 const MCSection *Section = it.first;
982 Sections.push_back(Section);
985 // Sort the sections into order.
986 // This is only done to ensure consistent output order across different runs.
987 std::sort(Sections.begin(), Sections.end(), SectionSort);
989 // Add terminating symbols for each section.
990 for (unsigned ID = 0, E = Sections.size(); ID != E; ID++) {
991 const MCSection *Section = Sections[ID];
992 MCSymbol *Sym = nullptr;
995 // We can't call MCSection::getLabelEndName, as it's only safe to do so
996 // if we know the section name up-front. For user-created sections, the
997 // resulting label may not be valid to use as a label. (section names can
998 // use a greater set of characters on some systems)
999 Sym = Asm->GetTempSymbol("debug_end", ID);
1000 Asm->OutStreamer.SwitchSection(Section);
1001 Asm->OutStreamer.EmitLabel(Sym);
1004 // Insert a final terminator.
1005 SectionMap[Section].push_back(SymbolCU(nullptr, Sym));
1009 // Emit all Dwarf sections that should come after the content.
1010 void DwarfDebug::endModule() {
1011 assert(CurFn == nullptr);
1012 assert(CurMI == nullptr);
1017 // End any existing sections.
1018 // TODO: Does this need to happen?
1021 // Finalize the debug info for the module.
1022 finalizeModuleInfo();
1026 // Emit all the DIEs into a debug info section.
1029 // Corresponding abbreviations into a abbrev section.
1030 emitAbbreviations();
1032 // Emit info into a debug aranges section.
1033 if (GenerateARangeSection)
1036 // Emit info into a debug ranges section.
1039 if (useSplitDwarf()) {
1042 emitDebugAbbrevDWO();
1045 // Emit DWO addresses.
1046 AddrPool.emit(*Asm, Asm->getObjFileLowering().getDwarfAddrSection());
1048 // Emit info into a debug loc section.
1051 // Emit info into the dwarf accelerator table sections.
1052 if (useDwarfAccelTables()) {
1055 emitAccelNamespaces();
1059 // Emit the pubnames and pubtypes sections if requested.
1060 if (HasDwarfPubSections) {
1061 emitDebugPubNames(GenerateGnuPubSections);
1062 emitDebugPubTypes(GenerateGnuPubSections);
1067 AbstractVariables.clear();
1069 // Reset these for the next Module if we have one.
1073 // Find abstract variable, if any, associated with Var.
1074 DbgVariable *DwarfDebug::getExistingAbstractVariable(const DIVariable &DV,
1075 DIVariable &Cleansed) {
1076 LLVMContext &Ctx = DV->getContext();
1077 // More then one inlined variable corresponds to one abstract variable.
1078 // FIXME: This duplication of variables when inlining should probably be
1079 // removed. It's done to allow each DIVariable to describe its location
1080 // because the DebugLoc on the dbg.value/declare isn't accurate. We should
1081 // make it accurate then remove this duplication/cleansing stuff.
1082 Cleansed = cleanseInlinedVariable(DV, Ctx);
1083 auto I = AbstractVariables.find(Cleansed);
1084 if (I != AbstractVariables.end())
1085 return I->second.get();
1089 DbgVariable *DwarfDebug::getExistingAbstractVariable(const DIVariable &DV) {
1090 DIVariable Cleansed;
1091 return getExistingAbstractVariable(DV, Cleansed);
1094 void DwarfDebug::createAbstractVariable(const DIVariable &Var,
1095 LexicalScope *Scope) {
1096 auto AbsDbgVariable = make_unique<DbgVariable>(Var, this);
1097 addScopeVariable(Scope, AbsDbgVariable.get());
1098 AbstractVariables[Var] = std::move(AbsDbgVariable);
1101 void DwarfDebug::ensureAbstractVariableIsCreated(const DIVariable &DV,
1102 const MDNode *ScopeNode) {
1103 DIVariable Cleansed = DV;
1104 if (getExistingAbstractVariable(DV, Cleansed))
1107 createAbstractVariable(Cleansed, LScopes.getOrCreateAbstractScope(ScopeNode));
1111 DwarfDebug::ensureAbstractVariableIsCreatedIfScoped(const DIVariable &DV,
1112 const MDNode *ScopeNode) {
1113 DIVariable Cleansed = DV;
1114 if (getExistingAbstractVariable(DV, Cleansed))
1117 if (LexicalScope *Scope = LScopes.findAbstractScope(ScopeNode))
1118 createAbstractVariable(Cleansed, Scope);
1121 // If Var is a current function argument then add it to CurrentFnArguments list.
1122 bool DwarfDebug::addCurrentFnArgument(DbgVariable *Var, LexicalScope *Scope) {
1123 if (!LScopes.isCurrentFunctionScope(Scope))
1125 DIVariable DV = Var->getVariable();
1126 if (DV.getTag() != dwarf::DW_TAG_arg_variable)
1128 unsigned ArgNo = DV.getArgNumber();
1132 size_t Size = CurrentFnArguments.size();
1134 CurrentFnArguments.resize(CurFn->getFunction()->arg_size());
1135 // llvm::Function argument size is not good indicator of how many
1136 // arguments does the function have at source level.
1138 CurrentFnArguments.resize(ArgNo * 2);
1139 CurrentFnArguments[ArgNo - 1] = Var;
1143 // Collect variable information from side table maintained by MMI.
1144 void DwarfDebug::collectVariableInfoFromMMITable(
1145 SmallPtrSet<const MDNode *, 16> &Processed) {
1146 for (const auto &VI : MMI->getVariableDbgInfo()) {
1149 Processed.insert(VI.Var);
1150 DIVariable DV(VI.Var);
1151 LexicalScope *Scope = LScopes.findLexicalScope(VI.Loc);
1153 // If variable scope is not found then skip this variable.
1157 ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode());
1158 ConcreteVariables.push_back(make_unique<DbgVariable>(DV, this));
1159 DbgVariable *RegVar = ConcreteVariables.back().get();
1160 RegVar->setFrameIndex(VI.Slot);
1161 addScopeVariable(Scope, RegVar);
1165 // Get .debug_loc entry for the instruction range starting at MI.
1166 static DebugLocEntry::Value getDebugLocValue(const MachineInstr *MI) {
1167 const MDNode *Var = MI->getDebugVariable();
1169 assert(MI->getNumOperands() == 3);
1170 if (MI->getOperand(0).isReg()) {
1171 MachineLocation MLoc;
1172 // If the second operand is an immediate, this is a
1173 // register-indirect address.
1174 if (!MI->getOperand(1).isImm())
1175 MLoc.set(MI->getOperand(0).getReg());
1177 MLoc.set(MI->getOperand(0).getReg(), MI->getOperand(1).getImm());
1178 return DebugLocEntry::Value(Var, MLoc);
1180 if (MI->getOperand(0).isImm())
1181 return DebugLocEntry::Value(Var, MI->getOperand(0).getImm());
1182 if (MI->getOperand(0).isFPImm())
1183 return DebugLocEntry::Value(Var, MI->getOperand(0).getFPImm());
1184 if (MI->getOperand(0).isCImm())
1185 return DebugLocEntry::Value(Var, MI->getOperand(0).getCImm());
1187 llvm_unreachable("Unexpected 3 operand DBG_VALUE instruction!");
1190 // Find variables for each lexical scope.
1192 DwarfDebug::collectVariableInfo(SmallPtrSet<const MDNode *, 16> &Processed) {
1193 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1194 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1196 // Grab the variable info that was squirreled away in the MMI side-table.
1197 collectVariableInfoFromMMITable(Processed);
1199 for (const auto &I : DbgValues) {
1200 DIVariable DV(I.first);
1201 if (Processed.count(DV))
1204 // Instruction ranges, specifying where DV is accessible.
1205 const auto &Ranges = I.second;
1209 LexicalScope *Scope = nullptr;
1210 if (DV.getTag() == dwarf::DW_TAG_arg_variable &&
1211 DISubprogram(DV.getContext()).describes(CurFn->getFunction()))
1212 Scope = LScopes.getCurrentFunctionScope();
1213 else if (MDNode *IA = DV.getInlinedAt()) {
1214 DebugLoc DL = DebugLoc::getFromDILocation(IA);
1215 Scope = LScopes.findInlinedScope(DebugLoc::get(
1216 DL.getLine(), DL.getCol(), DV.getContext(), IA));
1218 Scope = LScopes.findLexicalScope(DV.getContext());
1219 // If variable scope is not found then skip this variable.
1223 Processed.insert(DV);
1224 const MachineInstr *MInsn = Ranges.front().first;
1225 assert(MInsn->isDebugValue() && "History must begin with debug value");
1226 ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode());
1227 ConcreteVariables.push_back(make_unique<DbgVariable>(MInsn, this));
1228 DbgVariable *RegVar = ConcreteVariables.back().get();
1229 addScopeVariable(Scope, RegVar);
1231 // Check if the first DBG_VALUE is valid for the rest of the function.
1232 if (Ranges.size() == 1 && Ranges.front().second == nullptr)
1235 // Handle multiple DBG_VALUE instructions describing one variable.
1236 RegVar->setDotDebugLocOffset(DotDebugLocEntries.size());
1238 DotDebugLocEntries.resize(DotDebugLocEntries.size() + 1);
1239 DebugLocList &LocList = DotDebugLocEntries.back();
1241 Asm->GetTempSymbol("debug_loc", DotDebugLocEntries.size() - 1);
1242 SmallVector<DebugLocEntry, 4> &DebugLoc = LocList.List;
1243 for (auto I = Ranges.begin(), E = Ranges.end(); I != E; ++I) {
1244 const MachineInstr *Begin = I->first;
1245 const MachineInstr *End = I->second;
1246 assert(Begin->isDebugValue() && "Invalid History entry");
1248 // Check if a variable is unaccessible in this range.
1249 if (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() &&
1250 !Begin->getOperand(0).getReg())
1252 DEBUG(dbgs() << "DotDebugLoc Pair:\n" << "\t" << *Begin);
1254 DEBUG(dbgs() << "\t" << *End);
1256 DEBUG(dbgs() << "\tNULL\n");
1258 const MCSymbol *StartLabel = getLabelBeforeInsn(Begin);
1259 assert(StartLabel && "Forgot label before DBG_VALUE starting a range!");
1261 const MCSymbol *EndLabel;
1263 EndLabel = getLabelAfterInsn(End);
1264 else if (std::next(I) == Ranges.end())
1265 EndLabel = FunctionEndSym;
1267 EndLabel = getLabelBeforeInsn(std::next(I)->first);
1268 assert(EndLabel && "Forgot label after instruction ending a range!");
1270 DebugLocEntry Loc(StartLabel, EndLabel, getDebugLocValue(Begin), TheCU);
1271 if (DebugLoc.empty() || !DebugLoc.back().Merge(Loc))
1272 DebugLoc.push_back(std::move(Loc));
1276 // Collect info for variables that were optimized out.
1277 DIArray Variables = DISubprogram(FnScope->getScopeNode()).getVariables();
1278 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1279 DIVariable DV(Variables.getElement(i));
1280 assert(DV.isVariable());
1281 if (!Processed.insert(DV))
1283 if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext())) {
1284 ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode());
1285 ConcreteVariables.push_back(make_unique<DbgVariable>(DV, this));
1286 addScopeVariable(Scope, ConcreteVariables.back().get());
1291 // Return Label preceding the instruction.
1292 MCSymbol *DwarfDebug::getLabelBeforeInsn(const MachineInstr *MI) {
1293 MCSymbol *Label = LabelsBeforeInsn.lookup(MI);
1294 assert(Label && "Didn't insert label before instruction");
1298 // Return Label immediately following the instruction.
1299 MCSymbol *DwarfDebug::getLabelAfterInsn(const MachineInstr *MI) {
1300 return LabelsAfterInsn.lookup(MI);
1303 // Process beginning of an instruction.
1304 void DwarfDebug::beginInstruction(const MachineInstr *MI) {
1305 assert(CurMI == nullptr);
1307 // Check if source location changes, but ignore DBG_VALUE locations.
1308 if (!MI->isDebugValue()) {
1309 DebugLoc DL = MI->getDebugLoc();
1310 if (DL != PrevInstLoc && (!DL.isUnknown() || UnknownLocations)) {
1313 if (DL == PrologEndLoc) {
1314 Flags |= DWARF2_FLAG_PROLOGUE_END;
1315 PrologEndLoc = DebugLoc();
1317 if (PrologEndLoc.isUnknown())
1318 Flags |= DWARF2_FLAG_IS_STMT;
1320 if (!DL.isUnknown()) {
1321 const MDNode *Scope = DL.getScope(Asm->MF->getFunction()->getContext());
1322 recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags);
1324 recordSourceLine(0, 0, nullptr, 0);
1328 // Insert labels where requested.
1329 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1330 LabelsBeforeInsn.find(MI);
1333 if (I == LabelsBeforeInsn.end())
1336 // Label already assigned.
1341 PrevLabel = MMI->getContext().CreateTempSymbol();
1342 Asm->OutStreamer.EmitLabel(PrevLabel);
1344 I->second = PrevLabel;
1347 // Process end of an instruction.
1348 void DwarfDebug::endInstruction() {
1349 assert(CurMI != nullptr);
1350 // Don't create a new label after DBG_VALUE instructions.
1351 // They don't generate code.
1352 if (!CurMI->isDebugValue())
1353 PrevLabel = nullptr;
1355 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1356 LabelsAfterInsn.find(CurMI);
1360 if (I == LabelsAfterInsn.end())
1363 // Label already assigned.
1367 // We need a label after this instruction.
1369 PrevLabel = MMI->getContext().CreateTempSymbol();
1370 Asm->OutStreamer.EmitLabel(PrevLabel);
1372 I->second = PrevLabel;
1375 // Each LexicalScope has first instruction and last instruction to mark
1376 // beginning and end of a scope respectively. Create an inverse map that list
1377 // scopes starts (and ends) with an instruction. One instruction may start (or
1378 // end) multiple scopes. Ignore scopes that are not reachable.
1379 void DwarfDebug::identifyScopeMarkers() {
1380 SmallVector<LexicalScope *, 4> WorkList;
1381 WorkList.push_back(LScopes.getCurrentFunctionScope());
1382 while (!WorkList.empty()) {
1383 LexicalScope *S = WorkList.pop_back_val();
1385 const SmallVectorImpl<LexicalScope *> &Children = S->getChildren();
1386 if (!Children.empty())
1387 WorkList.append(Children.begin(), Children.end());
1389 if (S->isAbstractScope())
1392 for (const InsnRange &R : S->getRanges()) {
1393 assert(R.first && "InsnRange does not have first instruction!");
1394 assert(R.second && "InsnRange does not have second instruction!");
1395 requestLabelBeforeInsn(R.first);
1396 requestLabelAfterInsn(R.second);
1401 static DebugLoc findPrologueEndLoc(const MachineFunction *MF) {
1402 // First known non-DBG_VALUE and non-frame setup location marks
1403 // the beginning of the function body.
1404 for (const auto &MBB : *MF)
1405 for (const auto &MI : MBB)
1406 if (!MI.isDebugValue() && !MI.getFlag(MachineInstr::FrameSetup) &&
1407 !MI.getDebugLoc().isUnknown())
1408 return MI.getDebugLoc();
1412 // Gather pre-function debug information. Assumes being called immediately
1413 // after the function entry point has been emitted.
1414 void DwarfDebug::beginFunction(const MachineFunction *MF) {
1417 // If there's no debug info for the function we're not going to do anything.
1418 if (!MMI->hasDebugInfo())
1421 auto DI = FunctionDIs.find(MF->getFunction());
1422 if (DI == FunctionDIs.end())
1425 // Grab the lexical scopes for the function, if we don't have any of those
1426 // then we're not going to be able to do anything.
1427 LScopes.initialize(*MF);
1428 if (LScopes.empty())
1431 assert(DbgValues.empty() && "DbgValues map wasn't cleaned!");
1433 // Make sure that each lexical scope will have a begin/end label.
1434 identifyScopeMarkers();
1436 // Set DwarfDwarfCompileUnitID in MCContext to the Compile Unit this function
1437 // belongs to so that we add to the correct per-cu line table in the
1439 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1440 // FnScope->getScopeNode() and DI->second should represent the same function,
1441 // though they may not be the same MDNode due to inline functions merged in
1442 // LTO where the debug info metadata still differs (either due to distinct
1443 // written differences - two versions of a linkonce_odr function
1444 // written/copied into two separate files, or some sub-optimal metadata that
1445 // isn't structurally identical (see: file path/name info from clang, which
1446 // includes the directory of the cpp file being built, even when the file name
1447 // is absolute (such as an <> lookup header)))
1448 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1449 assert(TheCU && "Unable to find compile unit!");
1450 if (Asm->OutStreamer.hasRawTextSupport())
1451 // Use a single line table if we are generating assembly.
1452 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1454 Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID());
1456 // Emit a label for the function so that we have a beginning address.
1457 FunctionBeginSym = Asm->GetTempSymbol("func_begin", Asm->getFunctionNumber());
1458 // Assumes in correct section after the entry point.
1459 Asm->OutStreamer.EmitLabel(FunctionBeginSym);
1461 // Calculate history for local variables.
1462 calculateDbgValueHistory(MF, Asm->TM.getRegisterInfo(), DbgValues);
1464 // Request labels for the full history.
1465 for (const auto &I : DbgValues) {
1466 const auto &Ranges = I.second;
1470 // The first mention of a function argument gets the FunctionBeginSym
1471 // label, so arguments are visible when breaking at function entry.
1472 DIVariable DV(I.first);
1473 if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable &&
1474 getDISubprogram(DV.getContext()).describes(MF->getFunction()))
1475 LabelsBeforeInsn[Ranges.front().first] = FunctionBeginSym;
1477 for (const auto &Range : Ranges) {
1478 requestLabelBeforeInsn(Range.first);
1480 requestLabelAfterInsn(Range.second);
1484 PrevInstLoc = DebugLoc();
1485 PrevLabel = FunctionBeginSym;
1487 // Record beginning of function.
1488 PrologEndLoc = findPrologueEndLoc(MF);
1489 if (!PrologEndLoc.isUnknown()) {
1490 DebugLoc FnStartDL =
1491 PrologEndLoc.getFnDebugLoc(MF->getFunction()->getContext());
1493 FnStartDL.getLine(), FnStartDL.getCol(),
1494 FnStartDL.getScope(MF->getFunction()->getContext()),
1495 // We'd like to list the prologue as "not statements" but GDB behaves
1496 // poorly if we do that. Revisit this with caution/GDB (7.5+) testing.
1497 DWARF2_FLAG_IS_STMT);
1501 void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) {
1502 if (addCurrentFnArgument(Var, LS))
1504 SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS];
1505 DIVariable DV = Var->getVariable();
1506 // Variables with positive arg numbers are parameters.
1507 if (unsigned ArgNum = DV.getArgNumber()) {
1508 // Keep all parameters in order at the start of the variable list to ensure
1509 // function types are correct (no out-of-order parameters)
1511 // This could be improved by only doing it for optimized builds (unoptimized
1512 // builds have the right order to begin with), searching from the back (this
1513 // would catch the unoptimized case quickly), or doing a binary search
1514 // rather than linear search.
1515 SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin();
1516 while (I != Vars.end()) {
1517 unsigned CurNum = (*I)->getVariable().getArgNumber();
1518 // A local (non-parameter) variable has been found, insert immediately
1522 // A later indexed parameter has been found, insert immediately before it.
1523 if (CurNum > ArgNum)
1527 Vars.insert(I, Var);
1531 Vars.push_back(Var);
1534 // Gather and emit post-function debug information.
1535 void DwarfDebug::endFunction(const MachineFunction *MF) {
1536 // Every beginFunction(MF) call should be followed by an endFunction(MF) call,
1537 // though the beginFunction may not be called at all.
1538 // We should handle both cases.
1542 assert(CurFn == MF);
1543 assert(CurFn != nullptr);
1545 if (!MMI->hasDebugInfo() || LScopes.empty() ||
1546 !FunctionDIs.count(MF->getFunction())) {
1547 // If we don't have a lexical scope for this function then there will
1548 // be a hole in the range information. Keep note of this by setting the
1549 // previously used section to nullptr.
1550 PrevSection = nullptr;
1556 // Define end label for subprogram.
1557 FunctionEndSym = Asm->GetTempSymbol("func_end", Asm->getFunctionNumber());
1558 // Assumes in correct section after the entry point.
1559 Asm->OutStreamer.EmitLabel(FunctionEndSym);
1561 // Set DwarfDwarfCompileUnitID in MCContext to default value.
1562 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1564 SmallPtrSet<const MDNode *, 16> ProcessedVars;
1565 collectVariableInfo(ProcessedVars);
1567 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1568 DwarfCompileUnit &TheCU = *SPMap.lookup(FnScope->getScopeNode());
1570 // Construct abstract scopes.
1571 for (LexicalScope *AScope : LScopes.getAbstractScopesList()) {
1572 DISubprogram SP(AScope->getScopeNode());
1573 assert(SP.isSubprogram());
1574 // Collect info for variables that were optimized out.
1575 DIArray Variables = SP.getVariables();
1576 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1577 DIVariable DV(Variables.getElement(i));
1578 assert(DV && DV.isVariable());
1579 if (!ProcessedVars.insert(DV))
1581 ensureAbstractVariableIsCreated(DV, DV.getContext());
1583 constructAbstractSubprogramScopeDIE(TheCU, AScope);
1586 DIE &CurFnDIE = constructSubprogramScopeDIE(TheCU, FnScope);
1587 if (!CurFn->getTarget().Options.DisableFramePointerElim(*CurFn))
1588 TheCU.addFlag(CurFnDIE, dwarf::DW_AT_APPLE_omit_frame_ptr);
1590 // Add the range of this function to the list of ranges for the CU.
1591 RangeSpan Span(FunctionBeginSym, FunctionEndSym);
1592 TheCU.addRange(std::move(Span));
1593 PrevSection = Asm->getCurrentSection();
1597 // Ownership of DbgVariables is a bit subtle - ScopeVariables owns all the
1598 // DbgVariables except those that are also in AbstractVariables (since they
1599 // can be used cross-function)
1600 ScopeVariables.clear();
1601 CurrentFnArguments.clear();
1603 LabelsBeforeInsn.clear();
1604 LabelsAfterInsn.clear();
1605 PrevLabel = nullptr;
1609 // Register a source line with debug info. Returns the unique label that was
1610 // emitted and which provides correspondence to the source line list.
1611 void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S,
1616 unsigned Discriminator = 0;
1617 if (DIScope Scope = DIScope(S)) {
1618 assert(Scope.isScope());
1619 Fn = Scope.getFilename();
1620 Dir = Scope.getDirectory();
1621 if (Scope.isLexicalBlock())
1622 Discriminator = DILexicalBlock(S).getDiscriminator();
1624 unsigned CUID = Asm->OutStreamer.getContext().getDwarfCompileUnitID();
1625 Src = static_cast<DwarfCompileUnit &>(*InfoHolder.getUnits()[CUID])
1626 .getOrCreateSourceID(Fn, Dir);
1628 Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0,
1632 //===----------------------------------------------------------------------===//
1634 //===----------------------------------------------------------------------===//
1636 // Emit initial Dwarf sections with a label at the start of each one.
1637 void DwarfDebug::emitSectionLabels() {
1638 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
1640 // Dwarf sections base addresses.
1641 DwarfInfoSectionSym =
1642 emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info");
1643 if (useSplitDwarf()) {
1644 DwarfInfoDWOSectionSym =
1645 emitSectionSym(Asm, TLOF.getDwarfInfoDWOSection(), "section_info_dwo");
1646 DwarfTypesDWOSectionSym =
1647 emitSectionSym(Asm, TLOF.getDwarfTypesDWOSection(), "section_types_dwo");
1649 DwarfAbbrevSectionSym =
1650 emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev");
1651 if (useSplitDwarf())
1652 DwarfAbbrevDWOSectionSym = emitSectionSym(
1653 Asm, TLOF.getDwarfAbbrevDWOSection(), "section_abbrev_dwo");
1654 if (GenerateARangeSection)
1655 emitSectionSym(Asm, TLOF.getDwarfARangesSection());
1657 DwarfLineSectionSym =
1658 emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line");
1659 if (GenerateGnuPubSections) {
1660 DwarfGnuPubNamesSectionSym =
1661 emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection());
1662 DwarfGnuPubTypesSectionSym =
1663 emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection());
1664 } else if (HasDwarfPubSections) {
1665 emitSectionSym(Asm, TLOF.getDwarfPubNamesSection());
1666 emitSectionSym(Asm, TLOF.getDwarfPubTypesSection());
1669 DwarfStrSectionSym =
1670 emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string");
1671 if (useSplitDwarf()) {
1672 DwarfStrDWOSectionSym =
1673 emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string");
1674 DwarfAddrSectionSym =
1675 emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec");
1676 DwarfDebugLocSectionSym =
1677 emitSectionSym(Asm, TLOF.getDwarfLocDWOSection(), "skel_loc");
1679 DwarfDebugLocSectionSym =
1680 emitSectionSym(Asm, TLOF.getDwarfLocSection(), "section_debug_loc");
1681 DwarfDebugRangeSectionSym =
1682 emitSectionSym(Asm, TLOF.getDwarfRangesSection(), "debug_range");
1685 // Recursively emits a debug information entry.
1686 void DwarfDebug::emitDIE(DIE &Die) {
1687 // Get the abbreviation for this DIE.
1688 const DIEAbbrev &Abbrev = Die.getAbbrev();
1690 // Emit the code (index) for the abbreviation.
1691 if (Asm->isVerbose())
1692 Asm->OutStreamer.AddComment("Abbrev [" + Twine(Abbrev.getNumber()) +
1693 "] 0x" + Twine::utohexstr(Die.getOffset()) +
1694 ":0x" + Twine::utohexstr(Die.getSize()) + " " +
1695 dwarf::TagString(Abbrev.getTag()));
1696 Asm->EmitULEB128(Abbrev.getNumber());
1698 const SmallVectorImpl<DIEValue *> &Values = Die.getValues();
1699 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
1701 // Emit the DIE attribute values.
1702 for (unsigned i = 0, N = Values.size(); i < N; ++i) {
1703 dwarf::Attribute Attr = AbbrevData[i].getAttribute();
1704 dwarf::Form Form = AbbrevData[i].getForm();
1705 assert(Form && "Too many attributes for DIE (check abbreviation)");
1707 if (Asm->isVerbose()) {
1708 Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr));
1709 if (Attr == dwarf::DW_AT_accessibility)
1710 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(
1711 cast<DIEInteger>(Values[i])->getValue()));
1714 // Emit an attribute using the defined form.
1715 Values[i]->EmitValue(Asm, Form);
1718 // Emit the DIE children if any.
1719 if (Abbrev.hasChildren()) {
1720 for (auto &Child : Die.getChildren())
1723 Asm->OutStreamer.AddComment("End Of Children Mark");
1728 // Emit the debug info section.
1729 void DwarfDebug::emitDebugInfo() {
1730 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1732 Holder.emitUnits(this, DwarfAbbrevSectionSym);
1735 // Emit the abbreviation section.
1736 void DwarfDebug::emitAbbreviations() {
1737 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1739 Holder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection());
1742 // Emit the last address of the section and the end of the line matrix.
1743 void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) {
1744 // Define last address of section.
1745 Asm->OutStreamer.AddComment("Extended Op");
1748 Asm->OutStreamer.AddComment("Op size");
1749 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1);
1750 Asm->OutStreamer.AddComment("DW_LNE_set_address");
1751 Asm->EmitInt8(dwarf::DW_LNE_set_address);
1753 Asm->OutStreamer.AddComment("Section end label");
1755 Asm->OutStreamer.EmitSymbolValue(
1756 Asm->GetTempSymbol("section_end", SectionEnd),
1757 Asm->getDataLayout().getPointerSize());
1759 // Mark end of matrix.
1760 Asm->OutStreamer.AddComment("DW_LNE_end_sequence");
1766 // Emit visible names into a hashed accelerator table section.
1767 void DwarfDebug::emitAccelNames() {
1768 AccelNames.FinalizeTable(Asm, "Names");
1769 Asm->OutStreamer.SwitchSection(
1770 Asm->getObjFileLowering().getDwarfAccelNamesSection());
1771 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin");
1772 Asm->OutStreamer.EmitLabel(SectionBegin);
1774 // Emit the full data.
1775 AccelNames.Emit(Asm, SectionBegin, &InfoHolder);
1778 // Emit objective C classes and categories into a hashed accelerator table
1780 void DwarfDebug::emitAccelObjC() {
1781 AccelObjC.FinalizeTable(Asm, "ObjC");
1782 Asm->OutStreamer.SwitchSection(
1783 Asm->getObjFileLowering().getDwarfAccelObjCSection());
1784 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin");
1785 Asm->OutStreamer.EmitLabel(SectionBegin);
1787 // Emit the full data.
1788 AccelObjC.Emit(Asm, SectionBegin, &InfoHolder);
1791 // Emit namespace dies into a hashed accelerator table.
1792 void DwarfDebug::emitAccelNamespaces() {
1793 AccelNamespace.FinalizeTable(Asm, "namespac");
1794 Asm->OutStreamer.SwitchSection(
1795 Asm->getObjFileLowering().getDwarfAccelNamespaceSection());
1796 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin");
1797 Asm->OutStreamer.EmitLabel(SectionBegin);
1799 // Emit the full data.
1800 AccelNamespace.Emit(Asm, SectionBegin, &InfoHolder);
1803 // Emit type dies into a hashed accelerator table.
1804 void DwarfDebug::emitAccelTypes() {
1806 AccelTypes.FinalizeTable(Asm, "types");
1807 Asm->OutStreamer.SwitchSection(
1808 Asm->getObjFileLowering().getDwarfAccelTypesSection());
1809 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin");
1810 Asm->OutStreamer.EmitLabel(SectionBegin);
1812 // Emit the full data.
1813 AccelTypes.Emit(Asm, SectionBegin, &InfoHolder);
1816 // Public name handling.
1817 // The format for the various pubnames:
1819 // dwarf pubnames - offset/name pairs where the offset is the offset into the CU
1820 // for the DIE that is named.
1822 // gnu pubnames - offset/index value/name tuples where the offset is the offset
1823 // into the CU and the index value is computed according to the type of value
1824 // for the DIE that is named.
1826 // For type units the offset is the offset of the skeleton DIE. For split dwarf
1827 // it's the offset within the debug_info/debug_types dwo section, however, the
1828 // reference in the pubname header doesn't change.
1830 /// computeIndexValue - Compute the gdb index value for the DIE and CU.
1831 static dwarf::PubIndexEntryDescriptor computeIndexValue(DwarfUnit *CU,
1833 dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC;
1835 // We could have a specification DIE that has our most of our knowledge,
1836 // look for that now.
1837 DIEValue *SpecVal = Die->findAttribute(dwarf::DW_AT_specification);
1839 DIE &SpecDIE = cast<DIEEntry>(SpecVal)->getEntry();
1840 if (SpecDIE.findAttribute(dwarf::DW_AT_external))
1841 Linkage = dwarf::GIEL_EXTERNAL;
1842 } else if (Die->findAttribute(dwarf::DW_AT_external))
1843 Linkage = dwarf::GIEL_EXTERNAL;
1845 switch (Die->getTag()) {
1846 case dwarf::DW_TAG_class_type:
1847 case dwarf::DW_TAG_structure_type:
1848 case dwarf::DW_TAG_union_type:
1849 case dwarf::DW_TAG_enumeration_type:
1850 return dwarf::PubIndexEntryDescriptor(
1851 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus
1852 ? dwarf::GIEL_STATIC
1853 : dwarf::GIEL_EXTERNAL);
1854 case dwarf::DW_TAG_typedef:
1855 case dwarf::DW_TAG_base_type:
1856 case dwarf::DW_TAG_subrange_type:
1857 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC);
1858 case dwarf::DW_TAG_namespace:
1859 return dwarf::GIEK_TYPE;
1860 case dwarf::DW_TAG_subprogram:
1861 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage);
1862 case dwarf::DW_TAG_constant:
1863 case dwarf::DW_TAG_variable:
1864 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage);
1865 case dwarf::DW_TAG_enumerator:
1866 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE,
1867 dwarf::GIEL_STATIC);
1869 return dwarf::GIEK_NONE;
1873 /// emitDebugPubNames - Emit visible names into a debug pubnames section.
1875 void DwarfDebug::emitDebugPubNames(bool GnuStyle) {
1876 const MCSection *PSec =
1877 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection()
1878 : Asm->getObjFileLowering().getDwarfPubNamesSection();
1880 emitDebugPubSection(GnuStyle, PSec, "Names", &DwarfUnit::getGlobalNames);
1883 void DwarfDebug::emitDebugPubSection(
1884 bool GnuStyle, const MCSection *PSec, StringRef Name,
1885 const StringMap<const DIE *> &(DwarfUnit::*Accessor)() const) {
1886 for (const auto &NU : CUMap) {
1887 DwarfCompileUnit *TheU = NU.second;
1889 const auto &Globals = (TheU->*Accessor)();
1891 if (Globals.empty())
1894 if (auto Skeleton = static_cast<DwarfCompileUnit *>(TheU->getSkeleton()))
1896 unsigned ID = TheU->getUniqueID();
1898 // Start the dwarf pubnames section.
1899 Asm->OutStreamer.SwitchSection(PSec);
1902 Asm->OutStreamer.AddComment("Length of Public " + Name + " Info");
1903 MCSymbol *BeginLabel = Asm->GetTempSymbol("pub" + Name + "_begin", ID);
1904 MCSymbol *EndLabel = Asm->GetTempSymbol("pub" + Name + "_end", ID);
1905 Asm->EmitLabelDifference(EndLabel, BeginLabel, 4);
1907 Asm->OutStreamer.EmitLabel(BeginLabel);
1909 Asm->OutStreamer.AddComment("DWARF Version");
1910 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION);
1912 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info");
1913 Asm->EmitSectionOffset(TheU->getLabelBegin(), TheU->getSectionSym());
1915 Asm->OutStreamer.AddComment("Compilation Unit Length");
1916 Asm->EmitLabelDifference(TheU->getLabelEnd(), TheU->getLabelBegin(), 4);
1918 // Emit the pubnames for this compilation unit.
1919 for (const auto &GI : Globals) {
1920 const char *Name = GI.getKeyData();
1921 const DIE *Entity = GI.second;
1923 Asm->OutStreamer.AddComment("DIE offset");
1924 Asm->EmitInt32(Entity->getOffset());
1927 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheU, Entity);
1928 Asm->OutStreamer.AddComment(
1929 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " +
1930 dwarf::GDBIndexEntryLinkageString(Desc.Linkage));
1931 Asm->EmitInt8(Desc.toBits());
1934 Asm->OutStreamer.AddComment("External Name");
1935 Asm->OutStreamer.EmitBytes(StringRef(Name, GI.getKeyLength() + 1));
1938 Asm->OutStreamer.AddComment("End Mark");
1940 Asm->OutStreamer.EmitLabel(EndLabel);
1944 void DwarfDebug::emitDebugPubTypes(bool GnuStyle) {
1945 const MCSection *PSec =
1946 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection()
1947 : Asm->getObjFileLowering().getDwarfPubTypesSection();
1949 emitDebugPubSection(GnuStyle, PSec, "Types", &DwarfUnit::getGlobalTypes);
1952 // Emit visible names into a debug str section.
1953 void DwarfDebug::emitDebugStr() {
1954 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1955 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection());
1958 void DwarfDebug::emitDebugLocEntry(ByteStreamer &Streamer,
1959 const DebugLocEntry &Entry) {
1960 assert(Entry.getValues().size() == 1 &&
1961 "multi-value entries are not supported yet.");
1962 const DebugLocEntry::Value Value = Entry.getValues()[0];
1963 DIVariable DV(Value.getVariable());
1964 if (Value.isInt()) {
1965 DIBasicType BTy(resolve(DV.getType()));
1966 if (BTy.Verify() && (BTy.getEncoding() == dwarf::DW_ATE_signed ||
1967 BTy.getEncoding() == dwarf::DW_ATE_signed_char)) {
1968 Streamer.EmitInt8(dwarf::DW_OP_consts, "DW_OP_consts");
1969 Streamer.EmitSLEB128(Value.getInt());
1971 Streamer.EmitInt8(dwarf::DW_OP_constu, "DW_OP_constu");
1972 Streamer.EmitULEB128(Value.getInt());
1974 } else if (Value.isLocation()) {
1975 MachineLocation Loc = Value.getLoc();
1976 if (!DV.hasComplexAddress())
1978 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
1980 // Complex address entry.
1981 unsigned N = DV.getNumAddrElements();
1983 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) {
1984 if (Loc.getOffset()) {
1986 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
1987 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
1988 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
1989 Streamer.EmitSLEB128(DV.getAddrElement(1));
1991 // If first address element is OpPlus then emit
1992 // DW_OP_breg + Offset instead of DW_OP_reg + Offset.
1993 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1));
1994 Asm->EmitDwarfRegOp(Streamer, TLoc, DV.isIndirect());
1998 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2001 // Emit remaining complex address elements.
2002 for (; i < N; ++i) {
2003 uint64_t Element = DV.getAddrElement(i);
2004 if (Element == DIBuilder::OpPlus) {
2005 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
2006 Streamer.EmitULEB128(DV.getAddrElement(++i));
2007 } else if (Element == DIBuilder::OpDeref) {
2009 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
2011 llvm_unreachable("unknown Opcode found in complex address");
2015 // else ... ignore constant fp. There is not any good way to
2016 // to represent them here in dwarf.
2020 void DwarfDebug::emitDebugLocEntryLocation(const DebugLocEntry &Entry) {
2021 Asm->OutStreamer.AddComment("Loc expr size");
2022 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol();
2023 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol();
2024 Asm->EmitLabelDifference(end, begin, 2);
2025 Asm->OutStreamer.EmitLabel(begin);
2027 APByteStreamer Streamer(*Asm);
2028 emitDebugLocEntry(Streamer, Entry);
2030 Asm->OutStreamer.EmitLabel(end);
2033 // Emit locations into the debug loc section.
2034 void DwarfDebug::emitDebugLoc() {
2035 // Start the dwarf loc section.
2036 Asm->OutStreamer.SwitchSection(
2037 Asm->getObjFileLowering().getDwarfLocSection());
2038 unsigned char Size = Asm->getDataLayout().getPointerSize();
2039 for (const auto &DebugLoc : DotDebugLocEntries) {
2040 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2041 for (const auto &Entry : DebugLoc.List) {
2042 // Set up the range. This range is relative to the entry point of the
2043 // compile unit. This is a hard coded 0 for low_pc when we're emitting
2044 // ranges, or the DW_AT_low_pc on the compile unit otherwise.
2045 const DwarfCompileUnit *CU = Entry.getCU();
2046 if (CU->getRanges().size() == 1) {
2047 // Grab the begin symbol from the first range as our base.
2048 const MCSymbol *Base = CU->getRanges()[0].getStart();
2049 Asm->EmitLabelDifference(Entry.getBeginSym(), Base, Size);
2050 Asm->EmitLabelDifference(Entry.getEndSym(), Base, Size);
2052 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size);
2053 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size);
2056 emitDebugLocEntryLocation(Entry);
2058 Asm->OutStreamer.EmitIntValue(0, Size);
2059 Asm->OutStreamer.EmitIntValue(0, Size);
2063 void DwarfDebug::emitDebugLocDWO() {
2064 Asm->OutStreamer.SwitchSection(
2065 Asm->getObjFileLowering().getDwarfLocDWOSection());
2066 for (const auto &DebugLoc : DotDebugLocEntries) {
2067 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2068 for (const auto &Entry : DebugLoc.List) {
2069 // Just always use start_length for now - at least that's one address
2070 // rather than two. We could get fancier and try to, say, reuse an
2071 // address we know we've emitted elsewhere (the start of the function?
2072 // The start of the CU or CU subrange that encloses this range?)
2073 Asm->EmitInt8(dwarf::DW_LLE_start_length_entry);
2074 unsigned idx = AddrPool.getIndex(Entry.getBeginSym());
2075 Asm->EmitULEB128(idx);
2076 Asm->EmitLabelDifference(Entry.getEndSym(), Entry.getBeginSym(), 4);
2078 emitDebugLocEntryLocation(Entry);
2080 Asm->EmitInt8(dwarf::DW_LLE_end_of_list_entry);
2085 const MCSymbol *Start, *End;
2088 // Emit a debug aranges section, containing a CU lookup for any
2089 // address we can tie back to a CU.
2090 void DwarfDebug::emitDebugARanges() {
2091 // Start the dwarf aranges section.
2092 Asm->OutStreamer.SwitchSection(
2093 Asm->getObjFileLowering().getDwarfARangesSection());
2095 typedef DenseMap<DwarfCompileUnit *, std::vector<ArangeSpan>> SpansType;
2099 // Build a list of sections used.
2100 std::vector<const MCSection *> Sections;
2101 for (const auto &it : SectionMap) {
2102 const MCSection *Section = it.first;
2103 Sections.push_back(Section);
2106 // Sort the sections into order.
2107 // This is only done to ensure consistent output order across different runs.
2108 std::sort(Sections.begin(), Sections.end(), SectionSort);
2110 // Build a set of address spans, sorted by CU.
2111 for (const MCSection *Section : Sections) {
2112 SmallVector<SymbolCU, 8> &List = SectionMap[Section];
2113 if (List.size() < 2)
2116 // Sort the symbols by offset within the section.
2117 std::sort(List.begin(), List.end(),
2118 [&](const SymbolCU &A, const SymbolCU &B) {
2119 unsigned IA = A.Sym ? Asm->OutStreamer.GetSymbolOrder(A.Sym) : 0;
2120 unsigned IB = B.Sym ? Asm->OutStreamer.GetSymbolOrder(B.Sym) : 0;
2122 // Symbols with no order assigned should be placed at the end.
2123 // (e.g. section end labels)
2131 // If we have no section (e.g. common), just write out
2132 // individual spans for each symbol.
2134 for (const SymbolCU &Cur : List) {
2136 Span.Start = Cur.Sym;
2139 Spans[Cur.CU].push_back(Span);
2142 // Build spans between each label.
2143 const MCSymbol *StartSym = List[0].Sym;
2144 for (size_t n = 1, e = List.size(); n < e; n++) {
2145 const SymbolCU &Prev = List[n - 1];
2146 const SymbolCU &Cur = List[n];
2148 // Try and build the longest span we can within the same CU.
2149 if (Cur.CU != Prev.CU) {
2151 Span.Start = StartSym;
2153 Spans[Prev.CU].push_back(Span);
2160 unsigned PtrSize = Asm->getDataLayout().getPointerSize();
2162 // Build a list of CUs used.
2163 std::vector<DwarfCompileUnit *> CUs;
2164 for (const auto &it : Spans) {
2165 DwarfCompileUnit *CU = it.first;
2169 // Sort the CU list (again, to ensure consistent output order).
2170 std::sort(CUs.begin(), CUs.end(), [](const DwarfUnit *A, const DwarfUnit *B) {
2171 return A->getUniqueID() < B->getUniqueID();
2174 // Emit an arange table for each CU we used.
2175 for (DwarfCompileUnit *CU : CUs) {
2176 std::vector<ArangeSpan> &List = Spans[CU];
2178 // Emit size of content not including length itself.
2179 unsigned ContentSize =
2180 sizeof(int16_t) + // DWARF ARange version number
2181 sizeof(int32_t) + // Offset of CU in the .debug_info section
2182 sizeof(int8_t) + // Pointer Size (in bytes)
2183 sizeof(int8_t); // Segment Size (in bytes)
2185 unsigned TupleSize = PtrSize * 2;
2187 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple.
2189 OffsetToAlignment(sizeof(int32_t) + ContentSize, TupleSize);
2191 ContentSize += Padding;
2192 ContentSize += (List.size() + 1) * TupleSize;
2194 // For each compile unit, write the list of spans it covers.
2195 Asm->OutStreamer.AddComment("Length of ARange Set");
2196 Asm->EmitInt32(ContentSize);
2197 Asm->OutStreamer.AddComment("DWARF Arange version number");
2198 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION);
2199 Asm->OutStreamer.AddComment("Offset Into Debug Info Section");
2200 Asm->EmitSectionOffset(CU->getLocalLabelBegin(), CU->getLocalSectionSym());
2201 Asm->OutStreamer.AddComment("Address Size (in bytes)");
2202 Asm->EmitInt8(PtrSize);
2203 Asm->OutStreamer.AddComment("Segment Size (in bytes)");
2206 Asm->OutStreamer.EmitFill(Padding, 0xff);
2208 for (const ArangeSpan &Span : List) {
2209 Asm->EmitLabelReference(Span.Start, PtrSize);
2211 // Calculate the size as being from the span start to it's end.
2213 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize);
2215 // For symbols without an end marker (e.g. common), we
2216 // write a single arange entry containing just that one symbol.
2217 uint64_t Size = SymSize[Span.Start];
2221 Asm->OutStreamer.EmitIntValue(Size, PtrSize);
2225 Asm->OutStreamer.AddComment("ARange terminator");
2226 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2227 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2231 // Emit visible names into a debug ranges section.
2232 void DwarfDebug::emitDebugRanges() {
2233 // Start the dwarf ranges section.
2234 Asm->OutStreamer.SwitchSection(
2235 Asm->getObjFileLowering().getDwarfRangesSection());
2237 // Size for our labels.
2238 unsigned char Size = Asm->getDataLayout().getPointerSize();
2240 // Grab the specific ranges for the compile units in the module.
2241 for (const auto &I : CUMap) {
2242 DwarfCompileUnit *TheCU = I.second;
2244 // Iterate over the misc ranges for the compile units in the module.
2245 for (const RangeSpanList &List : TheCU->getRangeLists()) {
2246 // Emit our symbol so we can find the beginning of the range.
2247 Asm->OutStreamer.EmitLabel(List.getSym());
2249 for (const RangeSpan &Range : List.getRanges()) {
2250 const MCSymbol *Begin = Range.getStart();
2251 const MCSymbol *End = Range.getEnd();
2252 assert(Begin && "Range without a begin symbol?");
2253 assert(End && "Range without an end symbol?");
2254 if (TheCU->getRanges().size() == 1) {
2255 // Grab the begin symbol from the first range as our base.
2256 const MCSymbol *Base = TheCU->getRanges()[0].getStart();
2257 Asm->EmitLabelDifference(Begin, Base, Size);
2258 Asm->EmitLabelDifference(End, Base, Size);
2260 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2261 Asm->OutStreamer.EmitSymbolValue(End, Size);
2265 // And terminate the list with two 0 values.
2266 Asm->OutStreamer.EmitIntValue(0, Size);
2267 Asm->OutStreamer.EmitIntValue(0, Size);
2270 // Now emit a range for the CU itself.
2271 if (TheCU->getRanges().size() > 1) {
2272 Asm->OutStreamer.EmitLabel(
2273 Asm->GetTempSymbol("cu_ranges", TheCU->getUniqueID()));
2274 for (const RangeSpan &Range : TheCU->getRanges()) {
2275 const MCSymbol *Begin = Range.getStart();
2276 const MCSymbol *End = Range.getEnd();
2277 assert(Begin && "Range without a begin symbol?");
2278 assert(End && "Range without an end symbol?");
2279 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2280 Asm->OutStreamer.EmitSymbolValue(End, Size);
2282 // And terminate the list with two 0 values.
2283 Asm->OutStreamer.EmitIntValue(0, Size);
2284 Asm->OutStreamer.EmitIntValue(0, Size);
2289 // DWARF5 Experimental Separate Dwarf emitters.
2291 void DwarfDebug::initSkeletonUnit(const DwarfUnit &U, DIE &Die,
2292 std::unique_ptr<DwarfUnit> NewU) {
2293 NewU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name,
2294 U.getCUNode().getSplitDebugFilename());
2296 if (!CompilationDir.empty())
2297 NewU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
2299 addGnuPubAttributes(*NewU, Die);
2301 SkeletonHolder.addUnit(std::move(NewU));
2304 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list,
2305 // DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id,
2306 // DW_AT_addr_base, DW_AT_ranges_base.
2307 DwarfCompileUnit &DwarfDebug::constructSkeletonCU(const DwarfCompileUnit &CU) {
2309 auto OwnedUnit = make_unique<DwarfCompileUnit>(
2310 CU.getUniqueID(), CU.getCUNode(), Asm, this, &SkeletonHolder);
2311 DwarfCompileUnit &NewCU = *OwnedUnit;
2312 NewCU.initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
2313 DwarfInfoSectionSym);
2315 NewCU.initStmtList(DwarfLineSectionSym);
2317 initSkeletonUnit(CU, NewCU.getUnitDie(), std::move(OwnedUnit));
2322 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_dwo_name,
2324 DwarfTypeUnit &DwarfDebug::constructSkeletonTU(DwarfTypeUnit &TU) {
2325 DwarfCompileUnit &CU = static_cast<DwarfCompileUnit &>(
2326 *SkeletonHolder.getUnits()[TU.getCU().getUniqueID()]);
2328 auto OwnedUnit = make_unique<DwarfTypeUnit>(TU.getUniqueID(), CU, Asm, this,
2330 DwarfTypeUnit &NewTU = *OwnedUnit;
2331 NewTU.setTypeSignature(TU.getTypeSignature());
2332 NewTU.setType(nullptr);
2334 Asm->getObjFileLowering().getDwarfTypesSection(TU.getTypeSignature()));
2336 initSkeletonUnit(TU, NewTU.getUnitDie(), std::move(OwnedUnit));
2340 // Emit the .debug_info.dwo section for separated dwarf. This contains the
2341 // compile units that would normally be in debug_info.
2342 void DwarfDebug::emitDebugInfoDWO() {
2343 assert(useSplitDwarf() && "No split dwarf debug info?");
2344 // Don't pass an abbrev symbol, using a constant zero instead so as not to
2345 // emit relocations into the dwo file.
2346 InfoHolder.emitUnits(this, /* AbbrevSymbol */ nullptr);
2349 // Emit the .debug_abbrev.dwo section for separated dwarf. This contains the
2350 // abbreviations for the .debug_info.dwo section.
2351 void DwarfDebug::emitDebugAbbrevDWO() {
2352 assert(useSplitDwarf() && "No split dwarf?");
2353 InfoHolder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection());
2356 void DwarfDebug::emitDebugLineDWO() {
2357 assert(useSplitDwarf() && "No split dwarf?");
2358 Asm->OutStreamer.SwitchSection(
2359 Asm->getObjFileLowering().getDwarfLineDWOSection());
2360 SplitTypeUnitFileTable.Emit(Asm->OutStreamer);
2363 // Emit the .debug_str.dwo section for separated dwarf. This contains the
2364 // string section and is identical in format to traditional .debug_str
2366 void DwarfDebug::emitDebugStrDWO() {
2367 assert(useSplitDwarf() && "No split dwarf?");
2368 const MCSection *OffSec =
2369 Asm->getObjFileLowering().getDwarfStrOffDWOSection();
2370 const MCSymbol *StrSym = DwarfStrSectionSym;
2371 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(),
2375 MCDwarfDwoLineTable *DwarfDebug::getDwoLineTable(const DwarfCompileUnit &CU) {
2376 if (!useSplitDwarf())
2379 SplitTypeUnitFileTable.setCompilationDir(CU.getCUNode().getDirectory());
2380 return &SplitTypeUnitFileTable;
2383 static uint64_t makeTypeSignature(StringRef Identifier) {
2385 Hash.update(Identifier);
2386 // ... take the least significant 8 bytes and return those. Our MD5
2387 // implementation always returns its results in little endian, swap bytes
2389 MD5::MD5Result Result;
2391 return *reinterpret_cast<support::ulittle64_t *>(Result + 8);
2394 void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU,
2395 StringRef Identifier, DIE &RefDie,
2396 DICompositeType CTy) {
2397 // Fast path if we're building some type units and one has already used the
2398 // address pool we know we're going to throw away all this work anyway, so
2399 // don't bother building dependent types.
2400 if (!TypeUnitsUnderConstruction.empty() && AddrPool.hasBeenUsed())
2403 const DwarfTypeUnit *&TU = DwarfTypeUnits[CTy];
2405 CU.addDIETypeSignature(RefDie, *TU);
2409 bool TopLevelType = TypeUnitsUnderConstruction.empty();
2410 AddrPool.resetUsedFlag();
2412 auto OwnedUnit = make_unique<DwarfTypeUnit>(
2413 InfoHolder.getUnits().size() + TypeUnitsUnderConstruction.size(), CU, Asm,
2414 this, &InfoHolder, getDwoLineTable(CU));
2415 DwarfTypeUnit &NewTU = *OwnedUnit;
2416 DIE &UnitDie = NewTU.getUnitDie();
2418 TypeUnitsUnderConstruction.push_back(
2419 std::make_pair(std::move(OwnedUnit), CTy));
2421 NewTU.addUInt(UnitDie, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
2424 uint64_t Signature = makeTypeSignature(Identifier);
2425 NewTU.setTypeSignature(Signature);
2427 if (useSplitDwarf())
2428 NewTU.initSection(Asm->getObjFileLowering().getDwarfTypesDWOSection(),
2429 DwarfTypesDWOSectionSym);
2431 CU.applyStmtList(UnitDie);
2433 Asm->getObjFileLowering().getDwarfTypesSection(Signature));
2436 NewTU.setType(NewTU.createTypeDIE(CTy));
2439 auto TypeUnitsToAdd = std::move(TypeUnitsUnderConstruction);
2440 TypeUnitsUnderConstruction.clear();
2442 // Types referencing entries in the address table cannot be placed in type
2444 if (AddrPool.hasBeenUsed()) {
2446 // Remove all the types built while building this type.
2447 // This is pessimistic as some of these types might not be dependent on
2448 // the type that used an address.
2449 for (const auto &TU : TypeUnitsToAdd)
2450 DwarfTypeUnits.erase(TU.second);
2452 // Construct this type in the CU directly.
2453 // This is inefficient because all the dependent types will be rebuilt
2454 // from scratch, including building them in type units, discovering that
2455 // they depend on addresses, throwing them out and rebuilding them.
2456 CU.constructTypeDIE(RefDie, CTy);
2460 // If the type wasn't dependent on fission addresses, finish adding the type
2461 // and all its dependent types.
2462 for (auto &TU : TypeUnitsToAdd) {
2463 if (useSplitDwarf())
2464 TU.first->setSkeleton(constructSkeletonTU(*TU.first));
2465 InfoHolder.addUnit(std::move(TU.first));
2468 CU.addDIETypeSignature(RefDie, NewTU);
2471 void DwarfDebug::attachLowHighPC(DwarfCompileUnit &Unit, DIE &D,
2472 MCSymbol *Begin, MCSymbol *End) {
2473 assert(Begin && "Begin label should not be null!");
2474 assert(End && "End label should not be null!");
2475 assert(Begin->isDefined() && "Invalid starting label");
2476 assert(End->isDefined() && "Invalid end label");
2478 Unit.addLabelAddress(D, dwarf::DW_AT_low_pc, Begin);
2479 if (DwarfVersion < 4)
2480 Unit.addLabelAddress(D, dwarf::DW_AT_high_pc, End);
2482 Unit.addLabelDelta(D, dwarf::DW_AT_high_pc, End, Begin);
2485 // Accelerator table mutators - add each name along with its companion
2486 // DIE to the proper table while ensuring that the name that we're going
2487 // to reference is in the string table. We do this since the names we
2488 // add may not only be identical to the names in the DIE.
2489 void DwarfDebug::addAccelName(StringRef Name, const DIE &Die) {
2490 if (!useDwarfAccelTables())
2492 AccelNames.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2496 void DwarfDebug::addAccelObjC(StringRef Name, const DIE &Die) {
2497 if (!useDwarfAccelTables())
2499 AccelObjC.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2503 void DwarfDebug::addAccelNamespace(StringRef Name, const DIE &Die) {
2504 if (!useDwarfAccelTables())
2506 AccelNamespace.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),
2510 void DwarfDebug::addAccelType(StringRef Name, const DIE &Die, char Flags) {
2511 if (!useDwarfAccelTables())
2513 AccelTypes.AddName(Name, InfoHolder.getStringPool().getSymbol(*Asm, Name),