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 #define DEBUG_TYPE "dwarfdebug"
15 #include "ByteStreamer.h"
16 #include "DwarfDebug.h"
19 #include "DwarfAccelTable.h"
20 #include "DwarfUnit.h"
21 #include "llvm/ADT/STLExtras.h"
22 #include "llvm/ADT/Statistic.h"
23 #include "llvm/ADT/StringExtras.h"
24 #include "llvm/ADT/Triple.h"
25 #include "llvm/CodeGen/MachineFunction.h"
26 #include "llvm/CodeGen/MachineModuleInfo.h"
27 #include "llvm/IR/Constants.h"
28 #include "llvm/IR/DIBuilder.h"
29 #include "llvm/IR/DataLayout.h"
30 #include "llvm/IR/DebugInfo.h"
31 #include "llvm/IR/Instructions.h"
32 #include "llvm/IR/Module.h"
33 #include "llvm/IR/ValueHandle.h"
34 #include "llvm/MC/MCAsmInfo.h"
35 #include "llvm/MC/MCSection.h"
36 #include "llvm/MC/MCStreamer.h"
37 #include "llvm/MC/MCSymbol.h"
38 #include "llvm/Support/CommandLine.h"
39 #include "llvm/Support/Debug.h"
40 #include "llvm/Support/Dwarf.h"
41 #include "llvm/Support/ErrorHandling.h"
42 #include "llvm/Support/FormattedStream.h"
43 #include "llvm/Support/LEB128.h"
44 #include "llvm/Support/MD5.h"
45 #include "llvm/Support/Path.h"
46 #include "llvm/Support/Timer.h"
47 #include "llvm/Target/TargetFrameLowering.h"
48 #include "llvm/Target/TargetLoweringObjectFile.h"
49 #include "llvm/Target/TargetMachine.h"
50 #include "llvm/Target/TargetOptions.h"
51 #include "llvm/Target/TargetRegisterInfo.h"
55 DisableDebugInfoPrinting("disable-debug-info-print", cl::Hidden,
56 cl::desc("Disable debug info printing"));
58 static cl::opt<bool> UnknownLocations(
59 "use-unknown-locations", cl::Hidden,
60 cl::desc("Make an absence of debug location information explicit."),
63 static cl::opt<bool> GenerateCUHash("generate-cu-hash", cl::Hidden,
64 cl::desc("Add the CU hash as the dwo_id."),
68 GenerateGnuPubSections("generate-gnu-dwarf-pub-sections", cl::Hidden,
69 cl::desc("Generate GNU-style pubnames and pubtypes"),
72 static cl::opt<bool> GenerateARangeSection("generate-arange-section",
74 cl::desc("Generate dwarf aranges"),
78 enum DefaultOnOff { Default, Enable, Disable };
81 static cl::opt<DefaultOnOff>
82 DwarfAccelTables("dwarf-accel-tables", cl::Hidden,
83 cl::desc("Output prototype dwarf accelerator tables."),
84 cl::values(clEnumVal(Default, "Default for platform"),
85 clEnumVal(Enable, "Enabled"),
86 clEnumVal(Disable, "Disabled"), clEnumValEnd),
89 static cl::opt<DefaultOnOff>
90 SplitDwarf("split-dwarf", cl::Hidden,
91 cl::desc("Output DWARF5 split debug info."),
92 cl::values(clEnumVal(Default, "Default for platform"),
93 clEnumVal(Enable, "Enabled"),
94 clEnumVal(Disable, "Disabled"), clEnumValEnd),
97 static cl::opt<DefaultOnOff>
98 DwarfPubSections("generate-dwarf-pub-sections", cl::Hidden,
99 cl::desc("Generate DWARF pubnames and pubtypes sections"),
100 cl::values(clEnumVal(Default, "Default for platform"),
101 clEnumVal(Enable, "Enabled"),
102 clEnumVal(Disable, "Disabled"), clEnumValEnd),
105 static cl::opt<unsigned>
106 DwarfVersionNumber("dwarf-version", cl::Hidden,
107 cl::desc("Generate DWARF for dwarf version."), cl::init(0));
110 DwarfCURanges("generate-dwarf-cu-ranges", cl::Hidden,
111 cl::desc("Generate DW_AT_ranges for compile units"),
114 static const char *const DWARFGroupName = "DWARF Emission";
115 static const char *const DbgTimerName = "DWARF Debug Writer";
117 //===----------------------------------------------------------------------===//
121 /// resolve - Look in the DwarfDebug map for the MDNode that
122 /// corresponds to the reference.
123 template <typename T> T DbgVariable::resolve(DIRef<T> Ref) const {
124 return DD->resolve(Ref);
127 DIType DbgVariable::getType() const {
128 DIType Ty = Var.getType();
129 // FIXME: isBlockByrefVariable should be reformulated in terms of complex
130 // addresses instead.
131 if (Var.isBlockByrefVariable()) {
132 /* Byref variables, in Blocks, are declared by the programmer as
133 "SomeType VarName;", but the compiler creates a
134 __Block_byref_x_VarName struct, and gives the variable VarName
135 either the struct, or a pointer to the struct, as its type. This
136 is necessary for various behind-the-scenes things the compiler
137 needs to do with by-reference variables in blocks.
139 However, as far as the original *programmer* is concerned, the
140 variable should still have type 'SomeType', as originally declared.
142 The following function dives into the __Block_byref_x_VarName
143 struct to find the original type of the variable. This will be
144 passed back to the code generating the type for the Debug
145 Information Entry for the variable 'VarName'. 'VarName' will then
146 have the original type 'SomeType' in its debug information.
148 The original type 'SomeType' will be the type of the field named
149 'VarName' inside the __Block_byref_x_VarName struct.
151 NOTE: In order for this to not completely fail on the debugger
152 side, the Debug Information Entry for the variable VarName needs to
153 have a DW_AT_location that tells the debugger how to unwind through
154 the pointers and __Block_byref_x_VarName struct to find the actual
155 value of the variable. The function addBlockByrefType does this. */
157 uint16_t tag = Ty.getTag();
159 if (tag == dwarf::DW_TAG_pointer_type)
160 subType = resolve(DIDerivedType(Ty).getTypeDerivedFrom());
162 DIArray Elements = DICompositeType(subType).getTypeArray();
163 for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) {
164 DIDerivedType DT(Elements.getElement(i));
165 if (getName() == DT.getName())
166 return (resolve(DT.getTypeDerivedFrom()));
172 } // end llvm namespace
174 /// Return Dwarf Version by checking module flags.
175 static unsigned getDwarfVersionFromModule(const Module *M) {
176 Value *Val = M->getModuleFlag("Dwarf Version");
178 return dwarf::DWARF_VERSION;
179 return cast<ConstantInt>(Val)->getZExtValue();
182 DwarfDebug::DwarfDebug(AsmPrinter *A, Module *M)
183 : Asm(A), MMI(Asm->MMI), FirstCU(0), SourceIdMap(DIEValueAllocator),
184 PrevLabel(NULL), GlobalRangeCount(0),
185 InfoHolder(A, "info_string", DIEValueAllocator), HasCURanges(false),
186 UsedNonDefaultText(false),
187 SkeletonHolder(A, "skel_string", DIEValueAllocator) {
189 DwarfInfoSectionSym = DwarfAbbrevSectionSym = DwarfStrSectionSym = 0;
190 DwarfDebugRangeSectionSym = DwarfDebugLocSectionSym = DwarfLineSectionSym = 0;
191 DwarfAddrSectionSym = 0;
192 DwarfAbbrevDWOSectionSym = DwarfStrDWOSectionSym = 0;
193 FunctionBeginSym = FunctionEndSym = 0;
197 // Turn on accelerator tables for Darwin by default, pubnames by
198 // default for non-Darwin, and handle split dwarf.
199 bool IsDarwin = Triple(A->getTargetTriple()).isOSDarwin();
201 if (DwarfAccelTables == Default)
202 HasDwarfAccelTables = IsDarwin;
204 HasDwarfAccelTables = DwarfAccelTables == Enable;
206 if (SplitDwarf == Default)
207 HasSplitDwarf = false;
209 HasSplitDwarf = SplitDwarf == Enable;
211 if (DwarfPubSections == Default)
212 HasDwarfPubSections = !IsDarwin;
214 HasDwarfPubSections = DwarfPubSections == Enable;
216 DwarfVersion = DwarfVersionNumber
218 : getDwarfVersionFromModule(MMI->getModule());
221 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
226 // Switch to the specified MCSection and emit an assembler
227 // temporary label to it if SymbolStem is specified.
228 static MCSymbol *emitSectionSym(AsmPrinter *Asm, const MCSection *Section,
229 const char *SymbolStem = 0) {
230 Asm->OutStreamer.SwitchSection(Section);
234 MCSymbol *TmpSym = Asm->GetTempSymbol(SymbolStem);
235 Asm->OutStreamer.EmitLabel(TmpSym);
239 DwarfFile::~DwarfFile() {
240 for (DwarfUnit *DU : CUs)
244 MCSymbol *DwarfFile::getStringPoolSym() {
245 return Asm->GetTempSymbol(StringPref);
248 MCSymbol *DwarfFile::getStringPoolEntry(StringRef Str) {
249 std::pair<MCSymbol *, unsigned> &Entry =
250 StringPool.GetOrCreateValue(Str).getValue();
254 Entry.second = NextStringPoolNumber++;
255 return Entry.first = Asm->GetTempSymbol(StringPref, Entry.second);
258 unsigned DwarfFile::getStringPoolIndex(StringRef Str) {
259 std::pair<MCSymbol *, unsigned> &Entry =
260 StringPool.GetOrCreateValue(Str).getValue();
264 Entry.second = NextStringPoolNumber++;
265 Entry.first = Asm->GetTempSymbol(StringPref, Entry.second);
269 unsigned DwarfFile::getAddrPoolIndex(const MCSymbol *Sym, bool TLS) {
270 std::pair<AddrPool::iterator, bool> P = AddressPool.insert(
271 std::make_pair(Sym, AddressPoolEntry(NextAddrPoolNumber, TLS)));
273 ++NextAddrPoolNumber;
274 return P.first->second.Number;
277 // Define a unique number for the abbreviation.
279 void DwarfFile::assignAbbrevNumber(DIEAbbrev &Abbrev) {
280 // Check the set for priors.
281 DIEAbbrev *InSet = AbbreviationsSet.GetOrInsertNode(&Abbrev);
283 // If it's newly added.
284 if (InSet == &Abbrev) {
285 // Add to abbreviation list.
286 Abbreviations.push_back(&Abbrev);
288 // Assign the vector position + 1 as its number.
289 Abbrev.setNumber(Abbreviations.size());
291 // Assign existing abbreviation number.
292 Abbrev.setNumber(InSet->getNumber());
296 static bool isObjCClass(StringRef Name) {
297 return Name.startswith("+") || Name.startswith("-");
300 static bool hasObjCCategory(StringRef Name) {
301 if (!isObjCClass(Name))
304 return Name.find(") ") != StringRef::npos;
307 static void getObjCClassCategory(StringRef In, StringRef &Class,
308 StringRef &Category) {
309 if (!hasObjCCategory(In)) {
310 Class = In.slice(In.find('[') + 1, In.find(' '));
315 Class = In.slice(In.find('[') + 1, In.find('('));
316 Category = In.slice(In.find('[') + 1, In.find(' '));
320 static StringRef getObjCMethodName(StringRef In) {
321 return In.slice(In.find(' ') + 1, In.find(']'));
324 // Helper for sorting sections into a stable output order.
325 static bool SectionSort(const MCSection *A, const MCSection *B) {
326 std::string LA = (A ? A->getLabelBeginName() : "");
327 std::string LB = (B ? B->getLabelBeginName() : "");
331 // Add the various names to the Dwarf accelerator table names.
332 // TODO: Determine whether or not we should add names for programs
333 // that do not have a DW_AT_name or DW_AT_linkage_name field - this
334 // is only slightly different than the lookup of non-standard ObjC names.
335 static void addSubprogramNames(DwarfUnit *TheU, DISubprogram SP, DIE *Die) {
336 if (!SP.isDefinition())
338 TheU->addAccelName(SP.getName(), Die);
340 // If the linkage name is different than the name, go ahead and output
341 // that as well into the name table.
342 if (SP.getLinkageName() != "" && SP.getName() != SP.getLinkageName())
343 TheU->addAccelName(SP.getLinkageName(), Die);
345 // If this is an Objective-C selector name add it to the ObjC accelerator
347 if (isObjCClass(SP.getName())) {
348 StringRef Class, Category;
349 getObjCClassCategory(SP.getName(), Class, Category);
350 TheU->addAccelObjC(Class, Die);
352 TheU->addAccelObjC(Category, Die);
353 // Also add the base method name to the name table.
354 TheU->addAccelName(getObjCMethodName(SP.getName()), Die);
358 /// isSubprogramContext - Return true if Context is either a subprogram
359 /// or another context nested inside a subprogram.
360 bool DwarfDebug::isSubprogramContext(const MDNode *Context) {
363 DIDescriptor D(Context);
364 if (D.isSubprogram())
367 return isSubprogramContext(resolve(DIType(Context).getContext()));
371 // Find DIE for the given subprogram and attach appropriate DW_AT_low_pc
372 // and DW_AT_high_pc attributes. If there are global variables in this
373 // scope then create and insert DIEs for these variables.
374 DIE *DwarfDebug::updateSubprogramScopeDIE(DwarfCompileUnit *SPCU,
376 DIE *SPDie = SPCU->getDIE(SP);
378 assert(SPDie && "Unable to find subprogram DIE!");
380 // If we're updating an abstract DIE, then we will be adding the children and
381 // object pointer later on. But what we don't want to do is process the
382 // concrete DIE twice.
383 if (DIE *AbsSPDIE = AbstractSPDies.lookup(SP)) {
384 // Pick up abstract subprogram DIE.
386 SPCU->createAndAddDIE(dwarf::DW_TAG_subprogram, *SPCU->getUnitDie());
387 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_abstract_origin, AbsSPDIE);
389 DISubprogram SPDecl = SP.getFunctionDeclaration();
390 if (!SPDecl.isSubprogram()) {
391 // There is not any need to generate specification DIE for a function
392 // defined at compile unit level. If a function is defined inside another
393 // function then gdb prefers the definition at top level and but does not
394 // expect specification DIE in parent function. So avoid creating
395 // specification DIE for a function defined inside a function.
396 DIScope SPContext = resolve(SP.getContext());
397 if (SP.isDefinition() && !SPContext.isCompileUnit() &&
398 !SPContext.isFile() && !isSubprogramContext(SPContext)) {
399 SPCU->addFlag(SPDie, dwarf::DW_AT_declaration);
402 DICompositeType SPTy = SP.getType();
403 DIArray Args = SPTy.getTypeArray();
404 uint16_t SPTag = SPTy.getTag();
405 if (SPTag == dwarf::DW_TAG_subroutine_type)
406 SPCU->constructSubprogramArguments(*SPDie, Args);
407 DIE *SPDeclDie = SPDie;
408 SPDie = SPCU->createAndAddDIE(dwarf::DW_TAG_subprogram,
409 *SPCU->getUnitDie());
410 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_specification, SPDeclDie);
415 attachLowHighPC(SPCU, SPDie, FunctionBeginSym, FunctionEndSym);
417 const TargetRegisterInfo *RI = Asm->TM.getRegisterInfo();
418 MachineLocation Location(RI->getFrameRegister(*Asm->MF));
419 SPCU->addAddress(SPDie, dwarf::DW_AT_frame_base, Location);
421 // Add name to the name table, we do this here because we're guaranteed
422 // to have concrete versions of our DW_TAG_subprogram nodes.
423 addSubprogramNames(SPCU, SP, SPDie);
428 /// Check whether we should create a DIE for the given Scope, return true
429 /// if we don't create a DIE (the corresponding DIE is null).
430 bool DwarfDebug::isLexicalScopeDIENull(LexicalScope *Scope) {
431 if (Scope->isAbstractScope())
434 // We don't create a DIE if there is no Range.
435 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges();
439 if (Ranges.size() > 1)
442 // We don't create a DIE if we have a single Range and the end label
444 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin();
445 MCSymbol *End = getLabelAfterInsn(RI->second);
449 static void addSectionLabel(AsmPrinter *Asm, DwarfUnit *U, DIE *D,
450 dwarf::Attribute A, const MCSymbol *L,
451 const MCSymbol *Sec) {
452 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections())
453 U->addSectionLabel(D, A, L);
455 U->addSectionDelta(D, A, L, Sec);
458 void DwarfDebug::addScopeRangeList(DwarfCompileUnit *TheCU, DIE *ScopeDIE,
459 const SmallVectorImpl<InsnRange> &Range) {
460 // Emit offset in .debug_range as a relocatable label. emitDIE will handle
461 // emitting it appropriately.
462 MCSymbol *RangeSym = Asm->GetTempSymbol("debug_ranges", GlobalRangeCount++);
463 addSectionLabel(Asm, TheCU, ScopeDIE, dwarf::DW_AT_ranges, RangeSym,
464 DwarfDebugRangeSectionSym);
466 RangeSpanList List(RangeSym);
467 for (const InsnRange &R : Range) {
468 RangeSpan Span(getLabelBeforeInsn(R.first), getLabelAfterInsn(R.second));
469 List.addRange(std::move(Span));
472 // Add the range list to the set of ranges to be emitted.
473 TheCU->addRangeList(std::move(List));
476 // Construct new DW_TAG_lexical_block for this scope and attach
477 // DW_AT_low_pc/DW_AT_high_pc labels.
478 DIE *DwarfDebug::constructLexicalScopeDIE(DwarfCompileUnit *TheCU,
479 LexicalScope *Scope) {
480 if (isLexicalScopeDIENull(Scope))
483 DIE *ScopeDIE = new DIE(dwarf::DW_TAG_lexical_block);
484 if (Scope->isAbstractScope())
487 const SmallVectorImpl<InsnRange> &ScopeRanges = Scope->getRanges();
489 // If we have multiple ranges, emit them into the range section.
490 if (ScopeRanges.size() > 1) {
491 addScopeRangeList(TheCU, ScopeDIE, ScopeRanges);
495 // Construct the address range for this DIE.
496 SmallVectorImpl<InsnRange>::const_iterator RI = ScopeRanges.begin();
497 MCSymbol *Start = getLabelBeforeInsn(RI->first);
498 MCSymbol *End = getLabelAfterInsn(RI->second);
499 assert(End && "End label should not be null!");
501 assert(Start->isDefined() && "Invalid starting label for an inlined scope!");
502 assert(End->isDefined() && "Invalid end label for an inlined scope!");
504 attachLowHighPC(TheCU, ScopeDIE, Start, End);
509 // This scope represents inlined body of a function. Construct DIE to
510 // represent this concrete inlined copy of the function.
511 DIE *DwarfDebug::constructInlinedScopeDIE(DwarfCompileUnit *TheCU,
512 LexicalScope *Scope) {
513 const SmallVectorImpl<InsnRange> &ScopeRanges = Scope->getRanges();
514 assert(!ScopeRanges.empty() &&
515 "LexicalScope does not have instruction markers!");
517 if (!Scope->getScopeNode())
519 DIScope DS(Scope->getScopeNode());
520 DISubprogram InlinedSP = getDISubprogram(DS);
521 DIE *OriginDIE = TheCU->getDIE(InlinedSP);
523 DEBUG(dbgs() << "Unable to find original DIE for an inlined subprogram.");
527 DIE *ScopeDIE = new DIE(dwarf::DW_TAG_inlined_subroutine);
528 TheCU->addDIEEntry(ScopeDIE, dwarf::DW_AT_abstract_origin, OriginDIE);
530 // If we have multiple ranges, emit them into the range section.
531 if (ScopeRanges.size() > 1)
532 addScopeRangeList(TheCU, ScopeDIE, ScopeRanges);
534 SmallVectorImpl<InsnRange>::const_iterator RI = ScopeRanges.begin();
535 MCSymbol *StartLabel = getLabelBeforeInsn(RI->first);
536 MCSymbol *EndLabel = getLabelAfterInsn(RI->second);
538 if (StartLabel == 0 || EndLabel == 0)
539 llvm_unreachable("Unexpected Start and End labels for an inlined scope!");
541 assert(StartLabel->isDefined() &&
542 "Invalid starting label for an inlined scope!");
543 assert(EndLabel->isDefined() && "Invalid end label for an inlined scope!");
545 attachLowHighPC(TheCU, ScopeDIE, StartLabel, EndLabel);
548 InlinedSubprogramDIEs.insert(OriginDIE);
550 // Add the call site information to the DIE.
551 DILocation DL(Scope->getInlinedAt());
552 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_call_file, None,
553 getOrCreateSourceID(DL.getFilename(), DL.getDirectory(),
554 TheCU->getUniqueID()));
555 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_call_line, None, DL.getLineNumber());
557 // Add name to the name table, we do this here because we're guaranteed
558 // to have concrete versions of our DW_TAG_inlined_subprogram nodes.
559 addSubprogramNames(TheCU, InlinedSP, ScopeDIE);
564 DIE *DwarfDebug::createScopeChildrenDIE(DwarfCompileUnit *TheCU,
566 SmallVectorImpl<DIE *> &Children) {
567 DIE *ObjectPointer = NULL;
569 // Collect arguments for current function.
570 if (LScopes.isCurrentFunctionScope(Scope)) {
571 for (DbgVariable *ArgDV : CurrentFnArguments)
574 TheCU->constructVariableDIE(*ArgDV, Scope->isAbstractScope())) {
575 Children.push_back(Arg);
576 if (ArgDV->isObjectPointer())
580 // If this is a variadic function, add an unspecified parameter.
581 DISubprogram SP(Scope->getScopeNode());
582 DIArray FnArgs = SP.getType().getTypeArray();
583 if (FnArgs.getElement(FnArgs.getNumElements() - 1)
584 .isUnspecifiedParameter()) {
585 DIE *Ellipsis = new DIE(dwarf::DW_TAG_unspecified_parameters);
586 Children.push_back(Ellipsis);
590 // Collect lexical scope children first.
591 for (DbgVariable *DV : ScopeVariables.lookup(Scope))
592 if (DIE *Variable = TheCU->constructVariableDIE(*DV,
593 Scope->isAbstractScope())) {
594 Children.push_back(Variable);
595 if (DV->isObjectPointer())
596 ObjectPointer = Variable;
598 for (LexicalScope *LS : Scope->getChildren())
599 if (DIE *Nested = constructScopeDIE(TheCU, LS))
600 Children.push_back(Nested);
601 return ObjectPointer;
604 // Construct a DIE for this scope.
605 DIE *DwarfDebug::constructScopeDIE(DwarfCompileUnit *TheCU,
606 LexicalScope *Scope) {
607 if (!Scope || !Scope->getScopeNode())
610 DIScope DS(Scope->getScopeNode());
612 SmallVector<DIE *, 8> Children;
613 DIE *ObjectPointer = NULL;
614 bool ChildrenCreated = false;
616 // We try to create the scope DIE first, then the children DIEs. This will
617 // avoid creating un-used children then removing them later when we find out
618 // the scope DIE is null.
619 DIE *ScopeDIE = NULL;
620 if (Scope->getInlinedAt())
621 ScopeDIE = constructInlinedScopeDIE(TheCU, Scope);
622 else if (DS.isSubprogram()) {
623 ProcessedSPNodes.insert(DS);
624 if (Scope->isAbstractScope()) {
625 ScopeDIE = TheCU->getDIE(DS);
626 // Note down abstract DIE.
628 AbstractSPDies.insert(std::make_pair(DS, ScopeDIE));
630 ScopeDIE = updateSubprogramScopeDIE(TheCU, DISubprogram(DS));
632 // Early exit when we know the scope DIE is going to be null.
633 if (isLexicalScopeDIENull(Scope))
636 // We create children here when we know the scope DIE is not going to be
637 // null and the children will be added to the scope DIE.
638 ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children);
639 ChildrenCreated = true;
641 // There is no need to emit empty lexical block DIE.
642 std::pair<ImportedEntityMap::const_iterator,
643 ImportedEntityMap::const_iterator> Range =
645 ScopesWithImportedEntities.begin(),
646 ScopesWithImportedEntities.end(),
647 std::pair<const MDNode *, const MDNode *>(DS, (const MDNode *)0),
649 if (Children.empty() && Range.first == Range.second)
651 ScopeDIE = constructLexicalScopeDIE(TheCU, Scope);
652 assert(ScopeDIE && "Scope DIE should not be null.");
653 for (ImportedEntityMap::const_iterator i = Range.first; i != Range.second;
655 constructImportedEntityDIE(TheCU, i->second, ScopeDIE);
659 assert(Children.empty() &&
660 "We create children only when the scope DIE is not null.");
663 if (!ChildrenCreated)
664 // We create children when the scope DIE is not null.
665 ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children);
668 for (DIE *I : Children)
669 ScopeDIE->addChild(I);
671 if (DS.isSubprogram() && ObjectPointer != NULL)
672 TheCU->addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, ObjectPointer);
677 // Look up the source id with the given directory and source file names.
678 // If none currently exists, create a new id and insert it in the
679 // SourceIds map. This can update DirectoryNames and SourceFileNames maps
681 unsigned DwarfDebug::getOrCreateSourceID(StringRef FileName, StringRef DirName,
683 // If we print assembly, we can't separate .file entries according to
684 // compile units. Thus all files will belong to the default compile unit.
686 // FIXME: add a better feature test than hasRawTextSupport. Even better,
687 // extend .file to support this.
688 if (Asm->OutStreamer.hasRawTextSupport())
691 // If FE did not provide a file name, then assume stdin.
692 if (FileName.empty()) {
693 FileName = "<stdin>";
697 // TODO: this might not belong here. See if we can factor this better.
698 if (DirName == CompilationDir)
701 // FileIDCUMap stores the current ID for the given compile unit.
702 unsigned SrcId = FileIDCUMap[CUID] + 1;
704 // We look up the CUID/file/dir by concatenating them with a zero byte.
705 SmallString<128> NamePair;
706 NamePair += utostr(CUID);
709 NamePair += '\0'; // Zero bytes are not allowed in paths.
710 NamePair += FileName;
712 StringMapEntry<unsigned> &Ent = SourceIdMap.GetOrCreateValue(NamePair, SrcId);
713 if (Ent.getValue() != SrcId)
714 return Ent.getValue();
716 FileIDCUMap[CUID] = SrcId;
717 // Print out a .file directive to specify files for .loc directives.
718 Asm->OutStreamer.EmitDwarfFileDirective(SrcId, DirName, FileName, CUID);
723 void DwarfDebug::addGnuPubAttributes(DwarfUnit *U, DIE *D) const {
724 if (!GenerateGnuPubSections)
727 U->addFlag(D, dwarf::DW_AT_GNU_pubnames);
730 // Create new DwarfCompileUnit for the given metadata node with tag
731 // DW_TAG_compile_unit.
732 DwarfCompileUnit *DwarfDebug::constructDwarfCompileUnit(DICompileUnit DIUnit) {
733 StringRef FN = DIUnit.getFilename();
734 CompilationDir = DIUnit.getDirectory();
736 DIE *Die = new DIE(dwarf::DW_TAG_compile_unit);
737 DwarfCompileUnit *NewCU = new DwarfCompileUnit(
738 InfoHolder.getUnits().size(), Die, DIUnit, Asm, this, &InfoHolder);
739 InfoHolder.addUnit(NewCU);
741 FileIDCUMap[NewCU->getUniqueID()] = 0;
743 NewCU->addString(Die, dwarf::DW_AT_producer, DIUnit.getProducer());
744 NewCU->addUInt(Die, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
745 DIUnit.getLanguage());
746 NewCU->addString(Die, dwarf::DW_AT_name, FN);
748 if (!useSplitDwarf()) {
749 NewCU->initStmtList(DwarfLineSectionSym);
751 // If we're using split dwarf the compilation dir is going to be in the
752 // skeleton CU and so we don't need to duplicate it here.
753 if (!CompilationDir.empty())
754 NewCU->addString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
756 addGnuPubAttributes(NewCU, Die);
759 if (DIUnit.isOptimized())
760 NewCU->addFlag(Die, dwarf::DW_AT_APPLE_optimized);
762 StringRef Flags = DIUnit.getFlags();
764 NewCU->addString(Die, dwarf::DW_AT_APPLE_flags, Flags);
766 if (unsigned RVer = DIUnit.getRunTimeVersion())
767 NewCU->addUInt(Die, dwarf::DW_AT_APPLE_major_runtime_vers,
768 dwarf::DW_FORM_data1, RVer);
773 if (useSplitDwarf()) {
774 NewCU->initSection(Asm->getObjFileLowering().getDwarfInfoDWOSection(),
775 DwarfInfoDWOSectionSym);
776 NewCU->setSkeleton(constructSkeletonCU(NewCU));
778 NewCU->initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
779 DwarfInfoSectionSym);
781 CUMap.insert(std::make_pair(DIUnit, NewCU));
782 CUDieMap.insert(std::make_pair(Die, NewCU));
786 // Construct subprogram DIE.
787 void DwarfDebug::constructSubprogramDIE(DwarfCompileUnit *TheCU,
789 // FIXME: We should only call this routine once, however, during LTO if a
790 // program is defined in multiple CUs we could end up calling it out of
791 // beginModule as we walk the CUs.
793 DwarfCompileUnit *&CURef = SPMap[N];
799 if (!SP.isDefinition())
800 // This is a method declaration which will be handled while constructing
804 DIE *SubprogramDie = TheCU->getOrCreateSubprogramDIE(SP);
806 // Expose as a global name.
807 TheCU->addGlobalName(SP.getName(), SubprogramDie, resolve(SP.getContext()));
810 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit *TheCU,
812 DIImportedEntity Module(N);
813 assert(Module.Verify());
814 if (DIE *D = TheCU->getOrCreateContextDIE(Module.getContext()))
815 constructImportedEntityDIE(TheCU, Module, D);
818 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit *TheCU,
819 const MDNode *N, DIE *Context) {
820 DIImportedEntity Module(N);
821 assert(Module.Verify());
822 return constructImportedEntityDIE(TheCU, Module, Context);
825 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit *TheCU,
826 const DIImportedEntity &Module,
828 assert(Module.Verify() &&
829 "Use one of the MDNode * overloads to handle invalid metadata");
830 assert(Context && "Should always have a context for an imported_module");
831 DIE *IMDie = new DIE(Module.getTag());
832 TheCU->insertDIE(Module, IMDie);
834 DIDescriptor Entity = Module.getEntity();
835 if (Entity.isNameSpace())
836 EntityDie = TheCU->getOrCreateNameSpace(DINameSpace(Entity));
837 else if (Entity.isSubprogram())
838 EntityDie = TheCU->getOrCreateSubprogramDIE(DISubprogram(Entity));
839 else if (Entity.isType())
840 EntityDie = TheCU->getOrCreateTypeDIE(DIType(Entity));
842 EntityDie = TheCU->getDIE(Entity);
843 TheCU->addSourceLine(IMDie, Module.getLineNumber(),
844 Module.getContext().getFilename(),
845 Module.getContext().getDirectory());
846 TheCU->addDIEEntry(IMDie, dwarf::DW_AT_import, EntityDie);
847 StringRef Name = Module.getName();
849 TheCU->addString(IMDie, dwarf::DW_AT_name, Name);
850 Context->addChild(IMDie);
853 // Emit all Dwarf sections that should come prior to the content. Create
854 // global DIEs and emit initial debug info sections. This is invoked by
855 // the target AsmPrinter.
856 void DwarfDebug::beginModule() {
857 if (DisableDebugInfoPrinting)
860 const Module *M = MMI->getModule();
862 // If module has named metadata anchors then use them, otherwise scan the
863 // module using debug info finder to collect debug info.
864 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
867 TypeIdentifierMap = generateDITypeIdentifierMap(CU_Nodes);
869 // Emit initial sections so we can reference labels later.
872 for (MDNode *N : CU_Nodes->operands()) {
873 DICompileUnit CUNode(N);
874 DwarfCompileUnit *CU = constructDwarfCompileUnit(CUNode);
875 DIArray ImportedEntities = CUNode.getImportedEntities();
876 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
877 ScopesWithImportedEntities.push_back(std::make_pair(
878 DIImportedEntity(ImportedEntities.getElement(i)).getContext(),
879 ImportedEntities.getElement(i)));
880 std::sort(ScopesWithImportedEntities.begin(),
881 ScopesWithImportedEntities.end(), less_first());
882 DIArray GVs = CUNode.getGlobalVariables();
883 for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i)
884 CU->createGlobalVariableDIE(DIGlobalVariable(GVs.getElement(i)));
885 DIArray SPs = CUNode.getSubprograms();
886 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i)
887 constructSubprogramDIE(CU, SPs.getElement(i));
888 DIArray EnumTypes = CUNode.getEnumTypes();
889 for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i)
890 CU->getOrCreateTypeDIE(EnumTypes.getElement(i));
891 DIArray RetainedTypes = CUNode.getRetainedTypes();
892 for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i)
893 CU->getOrCreateTypeDIE(RetainedTypes.getElement(i));
894 // Emit imported_modules last so that the relevant context is already
896 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
897 constructImportedEntityDIE(CU, ImportedEntities.getElement(i));
900 // Tell MMI that we have debug info.
901 MMI->setDebugInfoAvailability(true);
903 // Prime section data.
904 SectionMap[Asm->getObjFileLowering().getTextSection()];
907 // Attach DW_AT_inline attribute with inlined subprogram DIEs.
908 void DwarfDebug::computeInlinedDIEs() {
909 // Attach DW_AT_inline attribute with inlined subprogram DIEs.
910 for (DIE *ISP : InlinedSubprogramDIEs)
911 FirstCU->addUInt(ISP, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined);
913 for (const auto &AI : AbstractSPDies) {
914 DIE *ISP = AI.second;
915 if (InlinedSubprogramDIEs.count(ISP))
917 FirstCU->addUInt(ISP, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined);
921 // Collect info for variables that were optimized out.
922 void DwarfDebug::collectDeadVariables() {
923 const Module *M = MMI->getModule();
925 if (NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu")) {
926 for (MDNode *N : CU_Nodes->operands()) {
927 DICompileUnit TheCU(N);
928 DIArray Subprograms = TheCU.getSubprograms();
929 for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) {
930 DISubprogram SP(Subprograms.getElement(i));
931 if (ProcessedSPNodes.count(SP) != 0)
933 if (!SP.isSubprogram())
935 if (!SP.isDefinition())
937 DIArray Variables = SP.getVariables();
938 if (Variables.getNumElements() == 0)
941 // Construct subprogram DIE and add variables DIEs.
942 DwarfCompileUnit *SPCU =
943 static_cast<DwarfCompileUnit *>(CUMap.lookup(TheCU));
944 assert(SPCU && "Unable to find Compile Unit!");
945 // FIXME: See the comment in constructSubprogramDIE about duplicate
947 constructSubprogramDIE(SPCU, SP);
948 DIE *SPDIE = SPCU->getDIE(SP);
949 for (unsigned vi = 0, ve = Variables.getNumElements(); vi != ve; ++vi) {
950 DIVariable DV(Variables.getElement(vi));
951 if (!DV.isVariable())
953 DbgVariable NewVar(DV, NULL, this);
954 if (DIE *VariableDIE = SPCU->constructVariableDIE(NewVar, false))
955 SPDIE->addChild(VariableDIE);
962 void DwarfDebug::finalizeModuleInfo() {
963 // Collect info for variables that were optimized out.
964 collectDeadVariables();
966 // Attach DW_AT_inline attribute with inlined subprogram DIEs.
967 computeInlinedDIEs();
969 // Handle anything that needs to be done on a per-unit basis after
970 // all other generation.
971 for (DwarfUnit *TheU : getUnits()) {
972 // Emit DW_AT_containing_type attribute to connect types with their
973 // vtable holding type.
974 TheU->constructContainingTypeDIEs();
976 // Add CU specific attributes if we need to add any.
977 if (TheU->getUnitDie()->getTag() == dwarf::DW_TAG_compile_unit) {
978 // If we're splitting the dwarf out now that we've got the entire
979 // CU then add the dwo id to it.
980 DwarfCompileUnit *SkCU =
981 static_cast<DwarfCompileUnit *>(TheU->getSkeleton());
982 if (useSplitDwarf()) {
983 // This should be a unique identifier when we want to build .dwp files.
985 if (GenerateCUHash) {
987 ID = CUHash.computeCUSignature(*TheU->getUnitDie());
989 TheU->addUInt(TheU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
990 dwarf::DW_FORM_data8, ID);
991 SkCU->addUInt(SkCU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
992 dwarf::DW_FORM_data8, ID);
995 // If we have code split among multiple sections or we've requested
996 // it then emit a DW_AT_ranges attribute on the unit that will remain
997 // in the .o file, otherwise add a DW_AT_low_pc.
998 // FIXME: Also add a high pc if we can.
999 // FIXME: We should use ranges if we have multiple compile units or
1000 // allow reordering of code ala .subsections_via_symbols in mach-o.
1001 DwarfCompileUnit *U = SkCU ? SkCU : static_cast<DwarfCompileUnit *>(TheU);
1002 if (useCURanges() && TheU->getRanges().size()) {
1003 addSectionLabel(Asm, U, U->getUnitDie(), dwarf::DW_AT_ranges,
1004 Asm->GetTempSymbol("cu_ranges", U->getUniqueID()),
1005 DwarfDebugRangeSectionSym);
1007 // A DW_AT_low_pc attribute may also be specified in combination with
1008 // DW_AT_ranges to specify the default base address for use in location
1009 // lists (see Section 2.6.2) and range lists (see Section 2.17.3).
1010 U->addUInt(U->getUnitDie(), dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr,
1013 U->addUInt(U->getUnitDie(), dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr,
1018 // Compute DIE offsets and sizes.
1019 InfoHolder.computeSizeAndOffsets();
1020 if (useSplitDwarf())
1021 SkeletonHolder.computeSizeAndOffsets();
1024 void DwarfDebug::endSections() {
1025 // Filter labels by section.
1026 for (const SymbolCU &SCU : ArangeLabels) {
1027 if (SCU.Sym->isInSection()) {
1028 // Make a note of this symbol and it's section.
1029 const MCSection *Section = &SCU.Sym->getSection();
1030 if (!Section->getKind().isMetadata())
1031 SectionMap[Section].push_back(SCU);
1033 // Some symbols (e.g. common/bss on mach-o) can have no section but still
1034 // appear in the output. This sucks as we rely on sections to build
1035 // arange spans. We can do it without, but it's icky.
1036 SectionMap[NULL].push_back(SCU);
1040 // Build a list of sections used.
1041 std::vector<const MCSection *> Sections;
1042 for (const auto &it : SectionMap) {
1043 const MCSection *Section = it.first;
1044 Sections.push_back(Section);
1047 // Sort the sections into order.
1048 // This is only done to ensure consistent output order across different runs.
1049 std::sort(Sections.begin(), Sections.end(), SectionSort);
1051 // Add terminating symbols for each section.
1052 for (unsigned ID = 0, E = Sections.size(); ID != E; ID++) {
1053 const MCSection *Section = Sections[ID];
1054 MCSymbol *Sym = NULL;
1057 // We can't call MCSection::getLabelEndName, as it's only safe to do so
1058 // if we know the section name up-front. For user-created sections, the
1059 // resulting label may not be valid to use as a label. (section names can
1060 // use a greater set of characters on some systems)
1061 Sym = Asm->GetTempSymbol("debug_end", ID);
1062 Asm->OutStreamer.SwitchSection(Section);
1063 Asm->OutStreamer.EmitLabel(Sym);
1066 // Insert a final terminator.
1067 SectionMap[Section].push_back(SymbolCU(NULL, Sym));
1070 // For now only turn on CU ranges if we've explicitly asked for it,
1071 // we have -ffunction-sections enabled, we've emitted a function
1072 // into a unique section, or we're using LTO. If we're using LTO then
1073 // we can't know that any particular function in the module is correlated
1074 // to a particular CU and so we need to be conservative. At this point all
1075 // sections should be finalized except for dwarf sections.
1076 HasCURanges = DwarfCURanges || UsedNonDefaultText || (CUMap.size() > 1) ||
1077 TargetMachine::getFunctionSections();
1080 // Emit all Dwarf sections that should come after the content.
1081 void DwarfDebug::endModule() {
1088 // End any existing sections.
1089 // TODO: Does this need to happen?
1092 // Finalize the debug info for the module.
1093 finalizeModuleInfo();
1097 // Emit all the DIEs into a debug info section.
1100 // Corresponding abbreviations into a abbrev section.
1101 emitAbbreviations();
1103 // Emit info into a debug loc section.
1106 // Emit info into a debug aranges section.
1107 if (GenerateARangeSection)
1110 // Emit info into a debug ranges section.
1113 if (useSplitDwarf()) {
1116 emitDebugAbbrevDWO();
1117 // Emit DWO addresses.
1118 InfoHolder.emitAddresses(Asm->getObjFileLowering().getDwarfAddrSection());
1121 // Emit info into the dwarf accelerator table sections.
1122 if (useDwarfAccelTables()) {
1125 emitAccelNamespaces();
1129 // Emit the pubnames and pubtypes sections if requested.
1130 if (HasDwarfPubSections) {
1131 emitDebugPubNames(GenerateGnuPubSections);
1132 emitDebugPubTypes(GenerateGnuPubSections);
1138 // Reset these for the next Module if we have one.
1142 // Find abstract variable, if any, associated with Var.
1143 DbgVariable *DwarfDebug::findAbstractVariable(DIVariable &DV,
1144 DebugLoc ScopeLoc) {
1145 LLVMContext &Ctx = DV->getContext();
1146 // More then one inlined variable corresponds to one abstract variable.
1147 DIVariable Var = cleanseInlinedVariable(DV, Ctx);
1148 DbgVariable *AbsDbgVariable = AbstractVariables.lookup(Var);
1150 return AbsDbgVariable;
1152 LexicalScope *Scope = LScopes.findAbstractScope(ScopeLoc.getScope(Ctx));
1156 AbsDbgVariable = new DbgVariable(Var, NULL, this);
1157 addScopeVariable(Scope, AbsDbgVariable);
1158 AbstractVariables[Var] = AbsDbgVariable;
1159 return AbsDbgVariable;
1162 // If Var is a current function argument then add it to CurrentFnArguments list.
1163 bool DwarfDebug::addCurrentFnArgument(DbgVariable *Var, LexicalScope *Scope) {
1164 if (!LScopes.isCurrentFunctionScope(Scope))
1166 DIVariable DV = Var->getVariable();
1167 if (DV.getTag() != dwarf::DW_TAG_arg_variable)
1169 unsigned ArgNo = DV.getArgNumber();
1173 size_t Size = CurrentFnArguments.size();
1175 CurrentFnArguments.resize(CurFn->getFunction()->arg_size());
1176 // llvm::Function argument size is not good indicator of how many
1177 // arguments does the function have at source level.
1179 CurrentFnArguments.resize(ArgNo * 2);
1180 CurrentFnArguments[ArgNo - 1] = Var;
1184 // Collect variable information from side table maintained by MMI.
1185 void DwarfDebug::collectVariableInfoFromMMITable(
1186 SmallPtrSet<const MDNode *, 16> &Processed) {
1187 for (const auto &VI : MMI->getVariableDbgInfo()) {
1190 Processed.insert(VI.Var);
1191 DIVariable DV(VI.Var);
1192 LexicalScope *Scope = LScopes.findLexicalScope(VI.Loc);
1194 // If variable scope is not found then skip this variable.
1198 DbgVariable *AbsDbgVariable = findAbstractVariable(DV, VI.Loc);
1199 DbgVariable *RegVar = new DbgVariable(DV, AbsDbgVariable, this);
1200 RegVar->setFrameIndex(VI.Slot);
1201 if (!addCurrentFnArgument(RegVar, Scope))
1202 addScopeVariable(Scope, RegVar);
1204 AbsDbgVariable->setFrameIndex(VI.Slot);
1208 // Return true if debug value, encoded by DBG_VALUE instruction, is in a
1210 static bool isDbgValueInDefinedReg(const MachineInstr *MI) {
1211 assert(MI->isDebugValue() && "Invalid DBG_VALUE machine instruction!");
1212 return MI->getNumOperands() == 3 && MI->getOperand(0).isReg() &&
1213 MI->getOperand(0).getReg() &&
1214 (MI->getOperand(1).isImm() ||
1215 (MI->getOperand(1).isReg() && MI->getOperand(1).getReg() == 0U));
1218 // Get .debug_loc entry for the instruction range starting at MI.
1219 static DotDebugLocEntry getDebugLocEntry(AsmPrinter *Asm,
1220 const MCSymbol *FLabel,
1221 const MCSymbol *SLabel,
1222 const MachineInstr *MI) {
1223 const MDNode *Var = MI->getOperand(MI->getNumOperands() - 1).getMetadata();
1225 assert(MI->getNumOperands() == 3);
1226 if (MI->getOperand(0).isReg()) {
1227 MachineLocation MLoc;
1228 // If the second operand is an immediate, this is a
1229 // register-indirect address.
1230 if (!MI->getOperand(1).isImm())
1231 MLoc.set(MI->getOperand(0).getReg());
1233 MLoc.set(MI->getOperand(0).getReg(), MI->getOperand(1).getImm());
1234 return DotDebugLocEntry(FLabel, SLabel, MLoc, Var);
1236 if (MI->getOperand(0).isImm())
1237 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getImm());
1238 if (MI->getOperand(0).isFPImm())
1239 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getFPImm());
1240 if (MI->getOperand(0).isCImm())
1241 return DotDebugLocEntry(FLabel, SLabel, MI->getOperand(0).getCImm());
1243 llvm_unreachable("Unexpected 3 operand DBG_VALUE instruction!");
1246 // Find variables for each lexical scope.
1248 DwarfDebug::collectVariableInfo(SmallPtrSet<const MDNode *, 16> &Processed) {
1250 // Grab the variable info that was squirreled away in the MMI side-table.
1251 collectVariableInfoFromMMITable(Processed);
1253 for (const MDNode *Var : UserVariables) {
1254 if (Processed.count(Var))
1257 // History contains relevant DBG_VALUE instructions for Var and instructions
1259 SmallVectorImpl<const MachineInstr *> &History = DbgValues[Var];
1260 if (History.empty())
1262 const MachineInstr *MInsn = History.front();
1265 LexicalScope *Scope = NULL;
1266 if (DV.getTag() == dwarf::DW_TAG_arg_variable &&
1267 DISubprogram(DV.getContext()).describes(CurFn->getFunction()))
1268 Scope = LScopes.getCurrentFunctionScope();
1269 else if (MDNode *IA = DV.getInlinedAt())
1270 Scope = LScopes.findInlinedScope(DebugLoc::getFromDILocation(IA));
1272 Scope = LScopes.findLexicalScope(cast<MDNode>(DV->getOperand(1)));
1273 // If variable scope is not found then skip this variable.
1277 Processed.insert(DV);
1278 assert(MInsn->isDebugValue() && "History must begin with debug value");
1279 DbgVariable *AbsVar = findAbstractVariable(DV, MInsn->getDebugLoc());
1280 DbgVariable *RegVar = new DbgVariable(DV, AbsVar, this);
1281 if (!addCurrentFnArgument(RegVar, Scope))
1282 addScopeVariable(Scope, RegVar);
1284 AbsVar->setMInsn(MInsn);
1286 // Simplify ranges that are fully coalesced.
1287 if (History.size() <= 1 ||
1288 (History.size() == 2 && MInsn->isIdenticalTo(History.back()))) {
1289 RegVar->setMInsn(MInsn);
1293 // Handle multiple DBG_VALUE instructions describing one variable.
1294 RegVar->setDotDebugLocOffset(DotDebugLocEntries.size());
1296 for (SmallVectorImpl<const MachineInstr *>::const_iterator
1297 HI = History.begin(),
1300 const MachineInstr *Begin = *HI;
1301 assert(Begin->isDebugValue() && "Invalid History entry");
1303 // Check if DBG_VALUE is truncating a range.
1304 if (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() &&
1305 !Begin->getOperand(0).getReg())
1308 // Compute the range for a register location.
1309 const MCSymbol *FLabel = getLabelBeforeInsn(Begin);
1310 const MCSymbol *SLabel = 0;
1313 // If Begin is the last instruction in History then its value is valid
1314 // until the end of the function.
1315 SLabel = FunctionEndSym;
1317 const MachineInstr *End = HI[1];
1318 DEBUG(dbgs() << "DotDebugLoc Pair:\n"
1319 << "\t" << *Begin << "\t" << *End << "\n");
1320 if (End->isDebugValue())
1321 SLabel = getLabelBeforeInsn(End);
1323 // End is a normal instruction clobbering the range.
1324 SLabel = getLabelAfterInsn(End);
1325 assert(SLabel && "Forgot label after clobber instruction");
1330 // The value is valid until the next DBG_VALUE or clobber.
1331 DotDebugLocEntries.push_back(
1332 getDebugLocEntry(Asm, FLabel, SLabel, Begin));
1334 DotDebugLocEntries.push_back(DotDebugLocEntry());
1337 // Collect info for variables that were optimized out.
1338 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1339 DIArray Variables = DISubprogram(FnScope->getScopeNode()).getVariables();
1340 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1341 DIVariable DV(Variables.getElement(i));
1342 if (!DV || !DV.isVariable() || !Processed.insert(DV))
1344 if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext()))
1345 addScopeVariable(Scope, new DbgVariable(DV, NULL, this));
1349 // Return Label preceding the instruction.
1350 MCSymbol *DwarfDebug::getLabelBeforeInsn(const MachineInstr *MI) {
1351 MCSymbol *Label = LabelsBeforeInsn.lookup(MI);
1352 assert(Label && "Didn't insert label before instruction");
1356 // Return Label immediately following the instruction.
1357 MCSymbol *DwarfDebug::getLabelAfterInsn(const MachineInstr *MI) {
1358 return LabelsAfterInsn.lookup(MI);
1361 // Process beginning of an instruction.
1362 void DwarfDebug::beginInstruction(const MachineInstr *MI) {
1365 // Check if source location changes, but ignore DBG_VALUE locations.
1366 if (!MI->isDebugValue()) {
1367 DebugLoc DL = MI->getDebugLoc();
1368 if (DL != PrevInstLoc && (!DL.isUnknown() || UnknownLocations)) {
1371 if (DL == PrologEndLoc) {
1372 Flags |= DWARF2_FLAG_PROLOGUE_END;
1373 PrologEndLoc = DebugLoc();
1375 if (PrologEndLoc.isUnknown())
1376 Flags |= DWARF2_FLAG_IS_STMT;
1378 if (!DL.isUnknown()) {
1379 const MDNode *Scope = DL.getScope(Asm->MF->getFunction()->getContext());
1380 recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags);
1382 recordSourceLine(0, 0, 0, 0);
1386 // Insert labels where requested.
1387 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1388 LabelsBeforeInsn.find(MI);
1391 if (I == LabelsBeforeInsn.end())
1394 // Label already assigned.
1399 PrevLabel = MMI->getContext().CreateTempSymbol();
1400 Asm->OutStreamer.EmitLabel(PrevLabel);
1402 I->second = PrevLabel;
1405 // Process end of an instruction.
1406 void DwarfDebug::endInstruction() {
1408 // Don't create a new label after DBG_VALUE instructions.
1409 // They don't generate code.
1410 if (!CurMI->isDebugValue())
1413 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1414 LabelsAfterInsn.find(CurMI);
1418 if (I == LabelsAfterInsn.end())
1421 // Label already assigned.
1425 // We need a label after this instruction.
1427 PrevLabel = MMI->getContext().CreateTempSymbol();
1428 Asm->OutStreamer.EmitLabel(PrevLabel);
1430 I->second = PrevLabel;
1433 // Each LexicalScope has first instruction and last instruction to mark
1434 // beginning and end of a scope respectively. Create an inverse map that list
1435 // scopes starts (and ends) with an instruction. One instruction may start (or
1436 // end) multiple scopes. Ignore scopes that are not reachable.
1437 void DwarfDebug::identifyScopeMarkers() {
1438 SmallVector<LexicalScope *, 4> WorkList;
1439 WorkList.push_back(LScopes.getCurrentFunctionScope());
1440 while (!WorkList.empty()) {
1441 LexicalScope *S = WorkList.pop_back_val();
1443 const SmallVectorImpl<LexicalScope *> &Children = S->getChildren();
1444 if (!Children.empty())
1445 WorkList.append(Children.begin(), Children.end());
1447 if (S->isAbstractScope())
1450 for (const InsnRange &R : S->getRanges()) {
1451 assert(R.first && "InsnRange does not have first instruction!");
1452 assert(R.second && "InsnRange does not have second instruction!");
1453 requestLabelBeforeInsn(R.first);
1454 requestLabelAfterInsn(R.second);
1459 // Gather pre-function debug information. Assumes being called immediately
1460 // after the function entry point has been emitted.
1461 void DwarfDebug::beginFunction(const MachineFunction *MF) {
1464 // If there's no debug info for the function we're not going to do anything.
1465 if (!MMI->hasDebugInfo())
1468 // Grab the lexical scopes for the function, if we don't have any of those
1469 // then we're not going to be able to do anything.
1470 LScopes.initialize(*MF);
1471 if (LScopes.empty())
1474 assert(UserVariables.empty() && DbgValues.empty() && "Maps weren't cleaned");
1476 // Make sure that each lexical scope will have a begin/end label.
1477 identifyScopeMarkers();
1479 // Set DwarfDwarfCompileUnitID in MCContext to the Compile Unit this function
1480 // belongs to so that we add to the correct per-cu line table in the
1482 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1483 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1484 assert(TheCU && "Unable to find compile unit!");
1485 if (Asm->OutStreamer.hasRawTextSupport())
1486 // Use a single line table if we are generating assembly.
1487 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1489 Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID());
1491 // Check the current section against the standard text section. If different
1492 // keep track so that we will know when we're emitting functions into multiple
1494 if (Asm->getObjFileLowering().getTextSection() != Asm->getCurrentSection())
1495 UsedNonDefaultText = true;
1497 // Emit a label for the function so that we have a beginning address.
1498 FunctionBeginSym = Asm->GetTempSymbol("func_begin", Asm->getFunctionNumber());
1499 // Assumes in correct section after the entry point.
1500 Asm->OutStreamer.EmitLabel(FunctionBeginSym);
1502 const TargetRegisterInfo *TRI = Asm->TM.getRegisterInfo();
1503 // LiveUserVar - Map physreg numbers to the MDNode they contain.
1504 std::vector<const MDNode *> LiveUserVar(TRI->getNumRegs());
1506 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end(); I != E;
1508 bool AtBlockEntry = true;
1509 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
1511 const MachineInstr *MI = II;
1513 if (MI->isDebugValue()) {
1514 assert(MI->getNumOperands() > 1 && "Invalid machine instruction!");
1516 // Keep track of user variables.
1518 MI->getOperand(MI->getNumOperands() - 1).getMetadata();
1520 // Variable is in a register, we need to check for clobbers.
1521 if (isDbgValueInDefinedReg(MI))
1522 LiveUserVar[MI->getOperand(0).getReg()] = Var;
1524 // Check the history of this variable.
1525 SmallVectorImpl<const MachineInstr *> &History = DbgValues[Var];
1526 if (History.empty()) {
1527 UserVariables.push_back(Var);
1528 // The first mention of a function argument gets the FunctionBeginSym
1529 // label, so arguments are visible when breaking at function entry.
1531 if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable &&
1532 getDISubprogram(DV.getContext()).describes(MF->getFunction()))
1533 LabelsBeforeInsn[MI] = FunctionBeginSym;
1535 // We have seen this variable before. Try to coalesce DBG_VALUEs.
1536 const MachineInstr *Prev = History.back();
1537 if (Prev->isDebugValue()) {
1538 // Coalesce identical entries at the end of History.
1539 if (History.size() >= 2 &&
1540 Prev->isIdenticalTo(History[History.size() - 2])) {
1541 DEBUG(dbgs() << "Coalescing identical DBG_VALUE entries:\n"
1542 << "\t" << *Prev << "\t"
1543 << *History[History.size() - 2] << "\n");
1547 // Terminate old register assignments that don't reach MI;
1548 MachineFunction::const_iterator PrevMBB = Prev->getParent();
1549 if (PrevMBB != I && (!AtBlockEntry || std::next(PrevMBB) != I) &&
1550 isDbgValueInDefinedReg(Prev)) {
1551 // Previous register assignment needs to terminate at the end of
1553 MachineBasicBlock::const_iterator LastMI =
1554 PrevMBB->getLastNonDebugInstr();
1555 if (LastMI == PrevMBB->end()) {
1556 // Drop DBG_VALUE for empty range.
1557 DEBUG(dbgs() << "Dropping DBG_VALUE for empty range:\n"
1558 << "\t" << *Prev << "\n");
1560 } else if (std::next(PrevMBB) != PrevMBB->getParent()->end())
1561 // Terminate after LastMI.
1562 History.push_back(LastMI);
1566 History.push_back(MI);
1568 // Not a DBG_VALUE instruction.
1569 if (!MI->isPosition())
1570 AtBlockEntry = false;
1572 // First known non-DBG_VALUE and non-frame setup location marks
1573 // the beginning of the function body.
1574 if (!MI->getFlag(MachineInstr::FrameSetup) &&
1575 (PrologEndLoc.isUnknown() && !MI->getDebugLoc().isUnknown()))
1576 PrologEndLoc = MI->getDebugLoc();
1578 // Check if the instruction clobbers any registers with debug vars.
1579 for (const MachineOperand &MO : MI->operands()) {
1580 if (!MO.isReg() || !MO.isDef() || !MO.getReg())
1582 for (MCRegAliasIterator AI(MO.getReg(), TRI, true); AI.isValid();
1585 const MDNode *Var = LiveUserVar[Reg];
1588 // Reg is now clobbered.
1589 LiveUserVar[Reg] = 0;
1591 // Was MD last defined by a DBG_VALUE referring to Reg?
1592 DbgValueHistoryMap::iterator HistI = DbgValues.find(Var);
1593 if (HistI == DbgValues.end())
1595 SmallVectorImpl<const MachineInstr *> &History = HistI->second;
1596 if (History.empty())
1598 const MachineInstr *Prev = History.back();
1599 // Sanity-check: Register assignments are terminated at the end of
1601 if (!Prev->isDebugValue() || Prev->getParent() != MI->getParent())
1603 // Is the variable still in Reg?
1604 if (!isDbgValueInDefinedReg(Prev) ||
1605 Prev->getOperand(0).getReg() != Reg)
1607 // Var is clobbered. Make sure the next instruction gets a label.
1608 History.push_back(MI);
1615 for (auto &I : DbgValues) {
1616 SmallVectorImpl<const MachineInstr *> &History = I.second;
1617 if (History.empty())
1620 // Make sure the final register assignments are terminated.
1621 const MachineInstr *Prev = History.back();
1622 if (Prev->isDebugValue() && isDbgValueInDefinedReg(Prev)) {
1623 const MachineBasicBlock *PrevMBB = Prev->getParent();
1624 MachineBasicBlock::const_iterator LastMI =
1625 PrevMBB->getLastNonDebugInstr();
1626 if (LastMI == PrevMBB->end())
1627 // Drop DBG_VALUE for empty range.
1629 else if (PrevMBB != &PrevMBB->getParent()->back()) {
1630 // Terminate after LastMI.
1631 History.push_back(LastMI);
1634 // Request labels for the full history.
1635 for (const MachineInstr *MI : History) {
1636 if (MI->isDebugValue())
1637 requestLabelBeforeInsn(MI);
1639 requestLabelAfterInsn(MI);
1643 PrevInstLoc = DebugLoc();
1644 PrevLabel = FunctionBeginSym;
1646 // Record beginning of function.
1647 if (!PrologEndLoc.isUnknown()) {
1648 DebugLoc FnStartDL =
1649 PrologEndLoc.getFnDebugLoc(MF->getFunction()->getContext());
1651 FnStartDL.getLine(), FnStartDL.getCol(),
1652 FnStartDL.getScope(MF->getFunction()->getContext()),
1653 // We'd like to list the prologue as "not statements" but GDB behaves
1654 // poorly if we do that. Revisit this with caution/GDB (7.5+) testing.
1655 DWARF2_FLAG_IS_STMT);
1659 void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) {
1660 SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS];
1661 DIVariable DV = Var->getVariable();
1662 // Variables with positive arg numbers are parameters.
1663 if (unsigned ArgNum = DV.getArgNumber()) {
1664 // Keep all parameters in order at the start of the variable list to ensure
1665 // function types are correct (no out-of-order parameters)
1667 // This could be improved by only doing it for optimized builds (unoptimized
1668 // builds have the right order to begin with), searching from the back (this
1669 // would catch the unoptimized case quickly), or doing a binary search
1670 // rather than linear search.
1671 SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin();
1672 while (I != Vars.end()) {
1673 unsigned CurNum = (*I)->getVariable().getArgNumber();
1674 // A local (non-parameter) variable has been found, insert immediately
1678 // A later indexed parameter has been found, insert immediately before it.
1679 if (CurNum > ArgNum)
1683 Vars.insert(I, Var);
1687 Vars.push_back(Var);
1690 // Gather and emit post-function debug information.
1691 void DwarfDebug::endFunction(const MachineFunction *MF) {
1692 // Every beginFunction(MF) call should be followed by an endFunction(MF) call,
1693 // though the beginFunction may not be called at all.
1694 // We should handle both cases.
1698 assert(CurFn == MF);
1701 if (!MMI->hasDebugInfo() || LScopes.empty()) {
1706 // Define end label for subprogram.
1707 FunctionEndSym = Asm->GetTempSymbol("func_end", Asm->getFunctionNumber());
1708 // Assumes in correct section after the entry point.
1709 Asm->OutStreamer.EmitLabel(FunctionEndSym);
1711 // Set DwarfDwarfCompileUnitID in MCContext to default value.
1712 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1714 SmallPtrSet<const MDNode *, 16> ProcessedVars;
1715 collectVariableInfo(ProcessedVars);
1717 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1718 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1719 assert(TheCU && "Unable to find compile unit!");
1721 // Construct abstract scopes.
1722 for (LexicalScope *AScope : LScopes.getAbstractScopesList()) {
1723 DISubprogram SP(AScope->getScopeNode());
1724 if (SP.isSubprogram()) {
1725 // Collect info for variables that were optimized out.
1726 DIArray Variables = SP.getVariables();
1727 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1728 DIVariable DV(Variables.getElement(i));
1729 if (!DV || !DV.isVariable() || !ProcessedVars.insert(DV))
1731 // Check that DbgVariable for DV wasn't created earlier, when
1732 // findAbstractVariable() was called for inlined instance of DV.
1733 LLVMContext &Ctx = DV->getContext();
1734 DIVariable CleanDV = cleanseInlinedVariable(DV, Ctx);
1735 if (AbstractVariables.lookup(CleanDV))
1737 if (LexicalScope *Scope = LScopes.findAbstractScope(DV.getContext()))
1738 addScopeVariable(Scope, new DbgVariable(DV, NULL, this));
1741 if (ProcessedSPNodes.count(AScope->getScopeNode()) == 0)
1742 constructScopeDIE(TheCU, AScope);
1745 DIE *CurFnDIE = constructScopeDIE(TheCU, FnScope);
1746 if (!CurFn->getTarget().Options.DisableFramePointerElim(*CurFn))
1747 TheCU->addFlag(CurFnDIE, dwarf::DW_AT_APPLE_omit_frame_ptr);
1749 // Add the range of this function to the list of ranges for the CU.
1750 RangeSpan Span(FunctionBeginSym, FunctionEndSym);
1751 TheCU->addRange(std::move(Span));
1754 for (auto &I : ScopeVariables)
1755 DeleteContainerPointers(I.second);
1756 ScopeVariables.clear();
1757 DeleteContainerPointers(CurrentFnArguments);
1758 UserVariables.clear();
1760 AbstractVariables.clear();
1761 LabelsBeforeInsn.clear();
1762 LabelsAfterInsn.clear();
1767 // Register a source line with debug info. Returns the unique label that was
1768 // emitted and which provides correspondence to the source line list.
1769 void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S,
1774 unsigned Discriminator = 0;
1776 DIDescriptor Scope(S);
1778 if (Scope.isCompileUnit()) {
1779 DICompileUnit CU(S);
1780 Fn = CU.getFilename();
1781 Dir = CU.getDirectory();
1782 } else if (Scope.isFile()) {
1784 Fn = F.getFilename();
1785 Dir = F.getDirectory();
1786 } else if (Scope.isSubprogram()) {
1788 Fn = SP.getFilename();
1789 Dir = SP.getDirectory();
1790 } else if (Scope.isLexicalBlockFile()) {
1791 DILexicalBlockFile DBF(S);
1792 Fn = DBF.getFilename();
1793 Dir = DBF.getDirectory();
1794 } else if (Scope.isLexicalBlock()) {
1795 DILexicalBlock DB(S);
1796 Fn = DB.getFilename();
1797 Dir = DB.getDirectory();
1798 Discriminator = DB.getDiscriminator();
1800 llvm_unreachable("Unexpected scope info");
1802 Src = getOrCreateSourceID(
1803 Fn, Dir, Asm->OutStreamer.getContext().getDwarfCompileUnitID());
1805 Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0,
1809 //===----------------------------------------------------------------------===//
1811 //===----------------------------------------------------------------------===//
1813 // Compute the size and offset of a DIE. The offset is relative to start of the
1814 // CU. It returns the offset after laying out the DIE.
1815 unsigned DwarfFile::computeSizeAndOffset(DIE *Die, unsigned Offset) {
1816 // Record the abbreviation.
1817 assignAbbrevNumber(Die->getAbbrev());
1819 // Get the abbreviation for this DIE.
1820 const DIEAbbrev &Abbrev = Die->getAbbrev();
1823 Die->setOffset(Offset);
1825 // Start the size with the size of abbreviation code.
1826 Offset += getULEB128Size(Die->getAbbrevNumber());
1828 const SmallVectorImpl<DIEValue *> &Values = Die->getValues();
1829 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
1831 // Size the DIE attribute values.
1832 for (unsigned i = 0, N = Values.size(); i < N; ++i)
1833 // Size attribute value.
1834 Offset += Values[i]->SizeOf(Asm, AbbrevData[i].getForm());
1836 // Get the children.
1837 const std::vector<DIE *> &Children = Die->getChildren();
1839 // Size the DIE children if any.
1840 if (!Children.empty()) {
1841 assert(Abbrev.hasChildren() && "Children flag not set");
1843 for (DIE *Child : Children)
1844 Offset = computeSizeAndOffset(Child, Offset);
1846 // End of children marker.
1847 Offset += sizeof(int8_t);
1850 Die->setSize(Offset - Die->getOffset());
1854 // Compute the size and offset for each DIE.
1855 void DwarfFile::computeSizeAndOffsets() {
1856 // Offset from the first CU in the debug info section is 0 initially.
1857 unsigned SecOffset = 0;
1859 // Iterate over each compile unit and set the size and offsets for each
1860 // DIE within each compile unit. All offsets are CU relative.
1861 for (DwarfUnit *TheU : CUs) {
1862 TheU->setDebugInfoOffset(SecOffset);
1864 // CU-relative offset is reset to 0 here.
1865 unsigned Offset = sizeof(int32_t) + // Length of Unit Info
1866 TheU->getHeaderSize(); // Unit-specific headers
1868 // EndOffset here is CU-relative, after laying out
1869 // all of the CU DIE.
1870 unsigned EndOffset = computeSizeAndOffset(TheU->getUnitDie(), Offset);
1871 SecOffset += EndOffset;
1875 // Emit initial Dwarf sections with a label at the start of each one.
1876 void DwarfDebug::emitSectionLabels() {
1877 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
1879 // Dwarf sections base addresses.
1880 DwarfInfoSectionSym =
1881 emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info");
1882 if (useSplitDwarf())
1883 DwarfInfoDWOSectionSym =
1884 emitSectionSym(Asm, TLOF.getDwarfInfoDWOSection(), "section_info_dwo");
1885 DwarfAbbrevSectionSym =
1886 emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev");
1887 if (useSplitDwarf())
1888 DwarfAbbrevDWOSectionSym = emitSectionSym(
1889 Asm, TLOF.getDwarfAbbrevDWOSection(), "section_abbrev_dwo");
1890 if (GenerateARangeSection)
1891 emitSectionSym(Asm, TLOF.getDwarfARangesSection());
1893 DwarfLineSectionSym =
1894 emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line");
1895 emitSectionSym(Asm, TLOF.getDwarfLocSection());
1896 if (GenerateGnuPubSections) {
1897 DwarfGnuPubNamesSectionSym =
1898 emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection());
1899 DwarfGnuPubTypesSectionSym =
1900 emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection());
1901 } else if (HasDwarfPubSections) {
1902 emitSectionSym(Asm, TLOF.getDwarfPubNamesSection());
1903 emitSectionSym(Asm, TLOF.getDwarfPubTypesSection());
1906 DwarfStrSectionSym =
1907 emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string");
1908 if (useSplitDwarf()) {
1909 DwarfStrDWOSectionSym =
1910 emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string");
1911 DwarfAddrSectionSym =
1912 emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec");
1914 DwarfDebugRangeSectionSym =
1915 emitSectionSym(Asm, TLOF.getDwarfRangesSection(), "debug_range");
1917 DwarfDebugLocSectionSym =
1918 emitSectionSym(Asm, TLOF.getDwarfLocSection(), "section_debug_loc");
1921 // Recursively emits a debug information entry.
1922 void DwarfDebug::emitDIE(DIE *Die) {
1923 // Get the abbreviation for this DIE.
1924 const DIEAbbrev &Abbrev = Die->getAbbrev();
1926 // Emit the code (index) for the abbreviation.
1927 if (Asm->isVerbose())
1928 Asm->OutStreamer.AddComment("Abbrev [" + Twine(Abbrev.getNumber()) +
1929 "] 0x" + Twine::utohexstr(Die->getOffset()) +
1930 ":0x" + Twine::utohexstr(Die->getSize()) + " " +
1931 dwarf::TagString(Abbrev.getTag()));
1932 Asm->EmitULEB128(Abbrev.getNumber());
1934 const SmallVectorImpl<DIEValue *> &Values = Die->getValues();
1935 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
1937 // Emit the DIE attribute values.
1938 for (unsigned i = 0, N = Values.size(); i < N; ++i) {
1939 dwarf::Attribute Attr = AbbrevData[i].getAttribute();
1940 dwarf::Form Form = AbbrevData[i].getForm();
1941 assert(Form && "Too many attributes for DIE (check abbreviation)");
1943 if (Asm->isVerbose()) {
1944 Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr));
1945 if (Attr == dwarf::DW_AT_accessibility)
1946 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(
1947 cast<DIEInteger>(Values[i])->getValue()));
1950 // Emit an attribute using the defined form.
1951 Values[i]->EmitValue(Asm, Form);
1954 // Emit the DIE children if any.
1955 if (Abbrev.hasChildren()) {
1956 const std::vector<DIE *> &Children = Die->getChildren();
1958 for (DIE *Child : Children)
1961 Asm->OutStreamer.AddComment("End Of Children Mark");
1966 // Emit the various dwarf units to the unit section USection with
1967 // the abbreviations going into ASection.
1968 void DwarfFile::emitUnits(DwarfDebug *DD, const MCSection *ASection,
1969 const MCSymbol *ASectionSym) {
1970 for (DwarfUnit *TheU : CUs) {
1971 DIE *Die = TheU->getUnitDie();
1972 const MCSection *USection = TheU->getSection();
1973 Asm->OutStreamer.SwitchSection(USection);
1975 // Emit the compile units header.
1976 Asm->OutStreamer.EmitLabel(TheU->getLabelBegin());
1978 // Emit size of content not including length itself
1979 Asm->OutStreamer.AddComment("Length of Unit");
1980 Asm->EmitInt32(TheU->getHeaderSize() + Die->getSize());
1982 TheU->emitHeader(ASection, ASectionSym);
1985 Asm->OutStreamer.EmitLabel(TheU->getLabelEnd());
1989 // Emit the debug info section.
1990 void DwarfDebug::emitDebugInfo() {
1991 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1993 Holder.emitUnits(this, Asm->getObjFileLowering().getDwarfAbbrevSection(),
1994 DwarfAbbrevSectionSym);
1997 // Emit the abbreviation section.
1998 void DwarfDebug::emitAbbreviations() {
1999 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
2001 Holder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection());
2004 void DwarfFile::emitAbbrevs(const MCSection *Section) {
2005 // Check to see if it is worth the effort.
2006 if (!Abbreviations.empty()) {
2007 // Start the debug abbrev section.
2008 Asm->OutStreamer.SwitchSection(Section);
2010 // For each abbrevation.
2011 for (const DIEAbbrev *Abbrev : Abbreviations) {
2012 // Emit the abbrevations code (base 1 index.)
2013 Asm->EmitULEB128(Abbrev->getNumber(), "Abbreviation Code");
2015 // Emit the abbreviations data.
2019 // Mark end of abbreviations.
2020 Asm->EmitULEB128(0, "EOM(3)");
2024 // Emit the last address of the section and the end of the line matrix.
2025 void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) {
2026 // Define last address of section.
2027 Asm->OutStreamer.AddComment("Extended Op");
2030 Asm->OutStreamer.AddComment("Op size");
2031 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1);
2032 Asm->OutStreamer.AddComment("DW_LNE_set_address");
2033 Asm->EmitInt8(dwarf::DW_LNE_set_address);
2035 Asm->OutStreamer.AddComment("Section end label");
2037 Asm->OutStreamer.EmitSymbolValue(
2038 Asm->GetTempSymbol("section_end", SectionEnd),
2039 Asm->getDataLayout().getPointerSize());
2041 // Mark end of matrix.
2042 Asm->OutStreamer.AddComment("DW_LNE_end_sequence");
2048 // Emit visible names into a hashed accelerator table section.
2049 void DwarfDebug::emitAccelNames() {
2051 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, dwarf::DW_FORM_data4));
2052 for (DwarfUnit *TheU : getUnits()) {
2053 for (const auto &GI : TheU->getAccelNames()) {
2054 StringRef Name = GI.getKey();
2055 for (const DIE *D : GI.second)
2056 AT.AddName(Name, D);
2060 AT.FinalizeTable(Asm, "Names");
2061 Asm->OutStreamer.SwitchSection(
2062 Asm->getObjFileLowering().getDwarfAccelNamesSection());
2063 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin");
2064 Asm->OutStreamer.EmitLabel(SectionBegin);
2066 // Emit the full data.
2067 AT.Emit(Asm, SectionBegin, &InfoHolder);
2070 // Emit objective C classes and categories into a hashed accelerator table
2072 void DwarfDebug::emitAccelObjC() {
2074 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, dwarf::DW_FORM_data4));
2075 for (DwarfUnit *TheU : getUnits()) {
2076 for (const auto &GI : TheU->getAccelObjC()) {
2077 StringRef Name = GI.getKey();
2078 for (const DIE *D : GI.second)
2079 AT.AddName(Name, D);
2083 AT.FinalizeTable(Asm, "ObjC");
2084 Asm->OutStreamer.SwitchSection(
2085 Asm->getObjFileLowering().getDwarfAccelObjCSection());
2086 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin");
2087 Asm->OutStreamer.EmitLabel(SectionBegin);
2089 // Emit the full data.
2090 AT.Emit(Asm, SectionBegin, &InfoHolder);
2093 // Emit namespace dies into a hashed accelerator table.
2094 void DwarfDebug::emitAccelNamespaces() {
2096 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, dwarf::DW_FORM_data4));
2097 for (DwarfUnit *TheU : getUnits()) {
2098 for (const auto &GI : TheU->getAccelNamespace()) {
2099 StringRef Name = GI.getKey();
2100 for (const DIE *D : GI.second)
2101 AT.AddName(Name, D);
2105 AT.FinalizeTable(Asm, "namespac");
2106 Asm->OutStreamer.SwitchSection(
2107 Asm->getObjFileLowering().getDwarfAccelNamespaceSection());
2108 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin");
2109 Asm->OutStreamer.EmitLabel(SectionBegin);
2111 // Emit the full data.
2112 AT.Emit(Asm, SectionBegin, &InfoHolder);
2115 // Emit type dies into a hashed accelerator table.
2116 void DwarfDebug::emitAccelTypes() {
2117 std::vector<DwarfAccelTable::Atom> Atoms;
2119 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, dwarf::DW_FORM_data4));
2121 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_tag, dwarf::DW_FORM_data2));
2123 DwarfAccelTable::Atom(dwarf::DW_ATOM_type_flags, dwarf::DW_FORM_data1));
2124 DwarfAccelTable AT(Atoms);
2125 for (DwarfUnit *TheU : getUnits()) {
2126 for (const auto &GI : TheU->getAccelTypes()) {
2127 StringRef Name = GI.getKey();
2128 for (const auto &DI : GI.second)
2129 AT.AddName(Name, DI.first, DI.second);
2133 AT.FinalizeTable(Asm, "types");
2134 Asm->OutStreamer.SwitchSection(
2135 Asm->getObjFileLowering().getDwarfAccelTypesSection());
2136 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin");
2137 Asm->OutStreamer.EmitLabel(SectionBegin);
2139 // Emit the full data.
2140 AT.Emit(Asm, SectionBegin, &InfoHolder);
2143 // Public name handling.
2144 // The format for the various pubnames:
2146 // dwarf pubnames - offset/name pairs where the offset is the offset into the CU
2147 // for the DIE that is named.
2149 // gnu pubnames - offset/index value/name tuples where the offset is the offset
2150 // into the CU and the index value is computed according to the type of value
2151 // for the DIE that is named.
2153 // For type units the offset is the offset of the skeleton DIE. For split dwarf
2154 // it's the offset within the debug_info/debug_types dwo section, however, the
2155 // reference in the pubname header doesn't change.
2157 /// computeIndexValue - Compute the gdb index value for the DIE and CU.
2158 static dwarf::PubIndexEntryDescriptor computeIndexValue(DwarfUnit *CU,
2160 dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC;
2162 // We could have a specification DIE that has our most of our knowledge,
2163 // look for that now.
2164 DIEValue *SpecVal = Die->findAttribute(dwarf::DW_AT_specification);
2166 DIE *SpecDIE = cast<DIEEntry>(SpecVal)->getEntry();
2167 if (SpecDIE->findAttribute(dwarf::DW_AT_external))
2168 Linkage = dwarf::GIEL_EXTERNAL;
2169 } else if (Die->findAttribute(dwarf::DW_AT_external))
2170 Linkage = dwarf::GIEL_EXTERNAL;
2172 switch (Die->getTag()) {
2173 case dwarf::DW_TAG_class_type:
2174 case dwarf::DW_TAG_structure_type:
2175 case dwarf::DW_TAG_union_type:
2176 case dwarf::DW_TAG_enumeration_type:
2177 return dwarf::PubIndexEntryDescriptor(
2178 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus
2179 ? dwarf::GIEL_STATIC
2180 : dwarf::GIEL_EXTERNAL);
2181 case dwarf::DW_TAG_typedef:
2182 case dwarf::DW_TAG_base_type:
2183 case dwarf::DW_TAG_subrange_type:
2184 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC);
2185 case dwarf::DW_TAG_namespace:
2186 return dwarf::GIEK_TYPE;
2187 case dwarf::DW_TAG_subprogram:
2188 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage);
2189 case dwarf::DW_TAG_constant:
2190 case dwarf::DW_TAG_variable:
2191 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage);
2192 case dwarf::DW_TAG_enumerator:
2193 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE,
2194 dwarf::GIEL_STATIC);
2196 return dwarf::GIEK_NONE;
2200 /// emitDebugPubNames - Emit visible names into a debug pubnames section.
2202 void DwarfDebug::emitDebugPubNames(bool GnuStyle) {
2203 const MCSection *PSec =
2204 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection()
2205 : Asm->getObjFileLowering().getDwarfPubNamesSection();
2207 emitDebugPubSection(GnuStyle, PSec, "Names", &DwarfUnit::getGlobalNames);
2210 void DwarfDebug::emitDebugPubSection(
2211 bool GnuStyle, const MCSection *PSec, StringRef Name,
2212 const StringMap<const DIE *> &(DwarfUnit::*Accessor)() const) {
2213 for (const auto &NU : CUMap) {
2214 DwarfCompileUnit *TheU = NU.second;
2216 const auto &Globals = (TheU->*Accessor)();
2218 if (Globals.empty())
2221 if (auto Skeleton = static_cast<DwarfCompileUnit *>(TheU->getSkeleton()))
2223 unsigned ID = TheU->getUniqueID();
2225 // Start the dwarf pubnames section.
2226 Asm->OutStreamer.SwitchSection(PSec);
2229 Asm->OutStreamer.AddComment("Length of Public " + Name + " Info");
2230 MCSymbol *BeginLabel = Asm->GetTempSymbol("pub" + Name + "_begin", ID);
2231 MCSymbol *EndLabel = Asm->GetTempSymbol("pub" + Name + "_end", ID);
2232 Asm->EmitLabelDifference(EndLabel, BeginLabel, 4);
2234 Asm->OutStreamer.EmitLabel(BeginLabel);
2236 Asm->OutStreamer.AddComment("DWARF Version");
2237 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION);
2239 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info");
2240 Asm->EmitSectionOffset(TheU->getLabelBegin(), TheU->getSectionSym());
2242 Asm->OutStreamer.AddComment("Compilation Unit Length");
2243 Asm->EmitLabelDifference(TheU->getLabelEnd(), TheU->getLabelBegin(), 4);
2245 // Emit the pubnames for this compilation unit.
2246 for (const auto &GI : Globals) {
2247 const char *Name = GI.getKeyData();
2248 const DIE *Entity = GI.second;
2250 Asm->OutStreamer.AddComment("DIE offset");
2251 Asm->EmitInt32(Entity->getOffset());
2254 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheU, Entity);
2255 Asm->OutStreamer.AddComment(
2256 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " +
2257 dwarf::GDBIndexEntryLinkageString(Desc.Linkage));
2258 Asm->EmitInt8(Desc.toBits());
2261 Asm->OutStreamer.AddComment("External Name");
2262 Asm->OutStreamer.EmitBytes(StringRef(Name, GI.getKeyLength() + 1));
2265 Asm->OutStreamer.AddComment("End Mark");
2267 Asm->OutStreamer.EmitLabel(EndLabel);
2271 void DwarfDebug::emitDebugPubTypes(bool GnuStyle) {
2272 const MCSection *PSec =
2273 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection()
2274 : Asm->getObjFileLowering().getDwarfPubTypesSection();
2276 emitDebugPubSection(GnuStyle, PSec, "Types", &DwarfUnit::getGlobalTypes);
2279 // Emit strings into a string section.
2280 void DwarfFile::emitStrings(const MCSection *StrSection,
2281 const MCSection *OffsetSection = NULL,
2282 const MCSymbol *StrSecSym = NULL) {
2284 if (StringPool.empty())
2287 // Start the dwarf str section.
2288 Asm->OutStreamer.SwitchSection(StrSection);
2290 // Get all of the string pool entries and put them in an array by their ID so
2291 // we can sort them.
2292 SmallVector<std::pair<unsigned, const StrPool::value_type *>, 64 > Entries;
2294 for (const auto &I : StringPool)
2295 Entries.push_back(std::make_pair(I.second.second, &I));
2297 array_pod_sort(Entries.begin(), Entries.end());
2299 for (const auto &Entry : Entries) {
2300 // Emit a label for reference from debug information entries.
2301 Asm->OutStreamer.EmitLabel(Entry.second->getValue().first);
2303 // Emit the string itself with a terminating null byte.
2304 Asm->OutStreamer.EmitBytes(StringRef(Entry.second->getKeyData(),
2305 Entry.second->getKeyLength() + 1));
2308 // If we've got an offset section go ahead and emit that now as well.
2309 if (OffsetSection) {
2310 Asm->OutStreamer.SwitchSection(OffsetSection);
2311 unsigned offset = 0;
2312 unsigned size = 4; // FIXME: DWARF64 is 8.
2313 for (const auto &Entry : Entries) {
2314 Asm->OutStreamer.EmitIntValue(offset, size);
2315 offset += Entry.second->getKeyLength() + 1;
2320 // Emit addresses into the section given.
2321 void DwarfFile::emitAddresses(const MCSection *AddrSection) {
2323 if (AddressPool.empty())
2326 // Start the dwarf addr section.
2327 Asm->OutStreamer.SwitchSection(AddrSection);
2329 // Order the address pool entries by ID
2330 SmallVector<const MCExpr *, 64> Entries(AddressPool.size());
2332 for (const auto &I : AddressPool)
2333 Entries[I.second.Number] =
2335 ? Asm->getObjFileLowering().getDebugThreadLocalSymbol(I.first)
2336 : MCSymbolRefExpr::Create(I.first, Asm->OutContext);
2338 for (const MCExpr *Entry : Entries)
2339 Asm->OutStreamer.EmitValue(Entry, Asm->getDataLayout().getPointerSize());
2342 // Emit visible names into a debug str section.
2343 void DwarfDebug::emitDebugStr() {
2344 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
2345 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection());
2348 void DwarfDebug::emitDebugLocEntry(ByteStreamer &Streamer,
2349 const DotDebugLocEntry &Entry) {
2350 DIVariable DV(Entry.getVariable());
2351 if (Entry.isInt()) {
2352 DIBasicType BTy(DV.getType());
2353 if (BTy.Verify() && (BTy.getEncoding() == dwarf::DW_ATE_signed ||
2354 BTy.getEncoding() == dwarf::DW_ATE_signed_char)) {
2355 Streamer.EmitInt8(dwarf::DW_OP_consts, "DW_OP_consts");
2356 Streamer.EmitSLEB128(Entry.getInt());
2358 Streamer.EmitInt8(dwarf::DW_OP_constu, "DW_OP_constu");
2359 Streamer.EmitULEB128(Entry.getInt());
2361 } else if (Entry.isLocation()) {
2362 MachineLocation Loc = Entry.getLoc();
2363 if (!DV.hasComplexAddress())
2365 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2367 // Complex address entry.
2368 unsigned N = DV.getNumAddrElements();
2370 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) {
2371 if (Loc.getOffset()) {
2373 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2374 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
2375 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
2376 Streamer.EmitSLEB128(DV.getAddrElement(1));
2378 // If first address element is OpPlus then emit
2379 // DW_OP_breg + Offset instead of DW_OP_reg + Offset.
2380 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1));
2381 Asm->EmitDwarfRegOp(Streamer, TLoc, DV.isIndirect());
2385 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2388 // Emit remaining complex address elements.
2389 for (; i < N; ++i) {
2390 uint64_t Element = DV.getAddrElement(i);
2391 if (Element == DIBuilder::OpPlus) {
2392 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
2393 Streamer.EmitULEB128(DV.getAddrElement(++i));
2394 } else if (Element == DIBuilder::OpDeref) {
2396 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
2398 llvm_unreachable("unknown Opcode found in complex address");
2402 // else ... ignore constant fp. There is not any good way to
2403 // to represent them here in dwarf.
2407 // Emit locations into the debug loc section.
2408 void DwarfDebug::emitDebugLoc() {
2409 if (DotDebugLocEntries.empty())
2412 for (SmallVectorImpl<DotDebugLocEntry>::iterator
2413 I = DotDebugLocEntries.begin(),
2414 E = DotDebugLocEntries.end();
2416 DotDebugLocEntry &Entry = *I;
2417 if (I + 1 != DotDebugLocEntries.end())
2421 // Start the dwarf loc section.
2422 Asm->OutStreamer.SwitchSection(
2423 Asm->getObjFileLowering().getDwarfLocSection());
2424 unsigned char Size = Asm->getDataLayout().getPointerSize();
2425 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("debug_loc", 0));
2427 for (SmallVectorImpl<DotDebugLocEntry>::const_iterator
2428 I = DotDebugLocEntries.begin(),
2429 E = DotDebugLocEntries.end();
2430 I != E; ++I, ++index) {
2431 const DotDebugLocEntry &Entry = *I;
2432 if (Entry.isMerged())
2435 if (Entry.isEmpty()) {
2436 Asm->OutStreamer.EmitIntValue(0, Size);
2437 Asm->OutStreamer.EmitIntValue(0, Size);
2438 Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("debug_loc", index));
2440 // Set up the range.
2441 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size);
2442 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size);
2443 Asm->OutStreamer.AddComment("Loc expr size");
2444 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol();
2445 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol();
2446 Asm->EmitLabelDifference(end, begin, 2);
2447 Asm->OutStreamer.EmitLabel(begin);
2449 APByteStreamer Streamer(*Asm);
2450 emitDebugLocEntry(Streamer, Entry);
2452 Asm->OutStreamer.EmitLabel(end);
2458 const MCSymbol *Start, *End;
2461 // Emit a debug aranges section, containing a CU lookup for any
2462 // address we can tie back to a CU.
2463 void DwarfDebug::emitDebugARanges() {
2464 // Start the dwarf aranges section.
2465 Asm->OutStreamer.SwitchSection(
2466 Asm->getObjFileLowering().getDwarfARangesSection());
2468 typedef DenseMap<DwarfCompileUnit *, std::vector<ArangeSpan> > SpansType;
2472 // Build a list of sections used.
2473 std::vector<const MCSection *> Sections;
2474 for (const auto &it : SectionMap) {
2475 const MCSection *Section = it.first;
2476 Sections.push_back(Section);
2479 // Sort the sections into order.
2480 // This is only done to ensure consistent output order across different runs.
2481 std::sort(Sections.begin(), Sections.end(), SectionSort);
2483 // Build a set of address spans, sorted by CU.
2484 for (const MCSection *Section : Sections) {
2485 SmallVector<SymbolCU, 8> &List = SectionMap[Section];
2486 if (List.size() < 2)
2489 // Sort the symbols by offset within the section.
2490 std::sort(List.begin(), List.end(),
2491 [&](const SymbolCU &A, const SymbolCU &B) {
2492 unsigned IA = A.Sym ? Asm->OutStreamer.GetSymbolOrder(A.Sym) : 0;
2493 unsigned IB = B.Sym ? Asm->OutStreamer.GetSymbolOrder(B.Sym) : 0;
2495 // Symbols with no order assigned should be placed at the end.
2496 // (e.g. section end labels)
2504 // If we have no section (e.g. common), just write out
2505 // individual spans for each symbol.
2506 if (Section == NULL) {
2507 for (const SymbolCU &Cur : List) {
2509 Span.Start = Cur.Sym;
2512 Spans[Cur.CU].push_back(Span);
2515 // Build spans between each label.
2516 const MCSymbol *StartSym = List[0].Sym;
2517 for (size_t n = 1, e = List.size(); n < e; n++) {
2518 const SymbolCU &Prev = List[n - 1];
2519 const SymbolCU &Cur = List[n];
2521 // Try and build the longest span we can within the same CU.
2522 if (Cur.CU != Prev.CU) {
2524 Span.Start = StartSym;
2526 Spans[Prev.CU].push_back(Span);
2533 unsigned PtrSize = Asm->getDataLayout().getPointerSize();
2535 // Build a list of CUs used.
2536 std::vector<DwarfCompileUnit *> CUs;
2537 for (const auto &it : Spans) {
2538 DwarfCompileUnit *CU = it.first;
2542 // Sort the CU list (again, to ensure consistent output order).
2543 std::sort(CUs.begin(), CUs.end(), [](const DwarfUnit *A, const DwarfUnit *B) {
2544 return A->getUniqueID() < B->getUniqueID();
2547 // Emit an arange table for each CU we used.
2548 for (DwarfCompileUnit *CU : CUs) {
2549 std::vector<ArangeSpan> &List = Spans[CU];
2551 // Emit size of content not including length itself.
2552 unsigned ContentSize =
2553 sizeof(int16_t) + // DWARF ARange version number
2554 sizeof(int32_t) + // Offset of CU in the .debug_info section
2555 sizeof(int8_t) + // Pointer Size (in bytes)
2556 sizeof(int8_t); // Segment Size (in bytes)
2558 unsigned TupleSize = PtrSize * 2;
2560 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple.
2562 OffsetToAlignment(sizeof(int32_t) + ContentSize, TupleSize);
2564 ContentSize += Padding;
2565 ContentSize += (List.size() + 1) * TupleSize;
2567 // For each compile unit, write the list of spans it covers.
2568 Asm->OutStreamer.AddComment("Length of ARange Set");
2569 Asm->EmitInt32(ContentSize);
2570 Asm->OutStreamer.AddComment("DWARF Arange version number");
2571 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION);
2572 Asm->OutStreamer.AddComment("Offset Into Debug Info Section");
2573 Asm->EmitSectionOffset(CU->getLocalLabelBegin(), CU->getLocalSectionSym());
2574 Asm->OutStreamer.AddComment("Address Size (in bytes)");
2575 Asm->EmitInt8(PtrSize);
2576 Asm->OutStreamer.AddComment("Segment Size (in bytes)");
2579 Asm->OutStreamer.EmitFill(Padding, 0xff);
2581 for (const ArangeSpan &Span : List) {
2582 Asm->EmitLabelReference(Span.Start, PtrSize);
2584 // Calculate the size as being from the span start to it's end.
2586 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize);
2588 // For symbols without an end marker (e.g. common), we
2589 // write a single arange entry containing just that one symbol.
2590 uint64_t Size = SymSize[Span.Start];
2594 Asm->OutStreamer.EmitIntValue(Size, PtrSize);
2598 Asm->OutStreamer.AddComment("ARange terminator");
2599 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2600 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2604 // Emit visible names into a debug ranges section.
2605 void DwarfDebug::emitDebugRanges() {
2606 // Start the dwarf ranges section.
2607 Asm->OutStreamer.SwitchSection(
2608 Asm->getObjFileLowering().getDwarfRangesSection());
2610 // Size for our labels.
2611 unsigned char Size = Asm->getDataLayout().getPointerSize();
2613 // Grab the specific ranges for the compile units in the module.
2614 for (const auto &I : CUMap) {
2615 DwarfCompileUnit *TheCU = I.second;
2617 // Emit a symbol so we can find the beginning of our ranges.
2618 Asm->OutStreamer.EmitLabel(TheCU->getLabelRange());
2620 // Iterate over the misc ranges for the compile units in the module.
2621 for (const RangeSpanList &List : TheCU->getRangeLists()) {
2622 // Emit our symbol so we can find the beginning of the range.
2623 Asm->OutStreamer.EmitLabel(List.getSym());
2625 for (const RangeSpan &Range : List.getRanges()) {
2626 const MCSymbol *Begin = Range.getStart();
2627 const MCSymbol *End = Range.getEnd();
2628 assert(Begin && "Range without a begin symbol?");
2629 assert(End && "Range without an end symbol?");
2630 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2631 Asm->OutStreamer.EmitSymbolValue(End, Size);
2634 // And terminate the list with two 0 values.
2635 Asm->OutStreamer.EmitIntValue(0, Size);
2636 Asm->OutStreamer.EmitIntValue(0, Size);
2639 // Now emit a range for the CU itself.
2640 if (useCURanges() && TheCU->getRanges().size()) {
2641 Asm->OutStreamer.EmitLabel(
2642 Asm->GetTempSymbol("cu_ranges", TheCU->getUniqueID()));
2643 for (const RangeSpan &Range : TheCU->getRanges()) {
2644 const MCSymbol *Begin = Range.getStart();
2645 const MCSymbol *End = Range.getEnd();
2646 assert(Begin && "Range without a begin symbol?");
2647 assert(End && "Range without an end symbol?");
2648 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2649 Asm->OutStreamer.EmitSymbolValue(End, Size);
2651 // And terminate the list with two 0 values.
2652 Asm->OutStreamer.EmitIntValue(0, Size);
2653 Asm->OutStreamer.EmitIntValue(0, Size);
2658 // DWARF5 Experimental Separate Dwarf emitters.
2660 void DwarfDebug::initSkeletonUnit(const DwarfUnit *U, DIE *Die,
2662 NewU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name,
2663 U->getCUNode().getSplitDebugFilename());
2665 // Relocate to the beginning of the addr_base section, else 0 for the
2666 // beginning of the one for this compile unit.
2667 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections())
2668 NewU->addSectionLabel(Die, dwarf::DW_AT_GNU_addr_base, DwarfAddrSectionSym);
2670 NewU->addSectionOffset(Die, dwarf::DW_AT_GNU_addr_base, 0);
2672 if (!CompilationDir.empty())
2673 NewU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
2675 addGnuPubAttributes(NewU, Die);
2677 SkeletonHolder.addUnit(NewU);
2680 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list,
2681 // DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id,
2682 // DW_AT_ranges_base, DW_AT_addr_base.
2683 // TODO: Implement DW_AT_ranges_base.
2684 DwarfCompileUnit *DwarfDebug::constructSkeletonCU(const DwarfCompileUnit *CU) {
2686 DIE *Die = new DIE(dwarf::DW_TAG_compile_unit);
2687 DwarfCompileUnit *NewCU = new DwarfCompileUnit(
2688 CU->getUniqueID(), Die, CU->getCUNode(), Asm, this, &SkeletonHolder);
2689 NewCU->initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
2690 DwarfInfoSectionSym);
2692 NewCU->initStmtList(DwarfLineSectionSym);
2694 initSkeletonUnit(CU, Die, NewCU);
2699 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_dwo_name,
2701 DwarfTypeUnit *DwarfDebug::constructSkeletonTU(DwarfTypeUnit *TU) {
2702 DwarfCompileUnit &CU = static_cast<DwarfCompileUnit &>(
2703 *SkeletonHolder.getUnits()[TU->getCU().getUniqueID()]);
2705 DIE *Die = new DIE(dwarf::DW_TAG_type_unit);
2706 DwarfTypeUnit *NewTU =
2707 new DwarfTypeUnit(TU->getUniqueID(), Die, CU, Asm, this, &SkeletonHolder);
2708 NewTU->setTypeSignature(TU->getTypeSignature());
2709 NewTU->setType(NULL);
2711 Asm->getObjFileLowering().getDwarfTypesSection(TU->getTypeSignature()));
2712 CU.applyStmtList(*Die);
2714 initSkeletonUnit(TU, Die, NewTU);
2718 // Emit the .debug_info.dwo section for separated dwarf. This contains the
2719 // compile units that would normally be in debug_info.
2720 void DwarfDebug::emitDebugInfoDWO() {
2721 assert(useSplitDwarf() && "No split dwarf debug info?");
2722 InfoHolder.emitUnits(this,
2723 Asm->getObjFileLowering().getDwarfAbbrevDWOSection(),
2724 DwarfAbbrevDWOSectionSym);
2727 // Emit the .debug_abbrev.dwo section for separated dwarf. This contains the
2728 // abbreviations for the .debug_info.dwo section.
2729 void DwarfDebug::emitDebugAbbrevDWO() {
2730 assert(useSplitDwarf() && "No split dwarf?");
2731 InfoHolder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection());
2734 // Emit the .debug_str.dwo section for separated dwarf. This contains the
2735 // string section and is identical in format to traditional .debug_str
2737 void DwarfDebug::emitDebugStrDWO() {
2738 assert(useSplitDwarf() && "No split dwarf?");
2739 const MCSection *OffSec =
2740 Asm->getObjFileLowering().getDwarfStrOffDWOSection();
2741 const MCSymbol *StrSym = DwarfStrSectionSym;
2742 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(),
2746 void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU,
2747 StringRef Identifier, DIE *RefDie,
2748 DICompositeType CTy) {
2749 // Flag the type unit reference as a declaration so that if it contains
2750 // members (implicit special members, static data member definitions, member
2751 // declarations for definitions in this CU, etc) consumers don't get confused
2752 // and think this is a full definition.
2753 CU.addFlag(RefDie, dwarf::DW_AT_declaration);
2755 const DwarfTypeUnit *&TU = DwarfTypeUnits[CTy];
2757 CU.addDIETypeSignature(RefDie, *TU);
2761 DIE *UnitDie = new DIE(dwarf::DW_TAG_type_unit);
2762 DwarfTypeUnit *NewTU = new DwarfTypeUnit(InfoHolder.getUnits().size(),
2763 UnitDie, CU, Asm, this, &InfoHolder);
2765 InfoHolder.addUnit(NewTU);
2767 NewTU->addUInt(UnitDie, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
2771 Hash.update(Identifier);
2772 // ... take the least significant 8 bytes and return those. Our MD5
2773 // implementation always returns its results in little endian, swap bytes
2775 MD5::MD5Result Result;
2777 uint64_t Signature = *reinterpret_cast<support::ulittle64_t *>(Result + 8);
2778 NewTU->setTypeSignature(Signature);
2779 if (useSplitDwarf())
2780 NewTU->setSkeleton(constructSkeletonTU(NewTU));
2782 CU.applyStmtList(*UnitDie);
2784 NewTU->setType(NewTU->createTypeDIE(CTy));
2788 ? Asm->getObjFileLowering().getDwarfTypesDWOSection(Signature)
2789 : Asm->getObjFileLowering().getDwarfTypesSection(Signature));
2791 CU.addDIETypeSignature(RefDie, *NewTU);
2794 void DwarfDebug::attachLowHighPC(DwarfCompileUnit *Unit, DIE *D,
2795 MCSymbol *Begin, MCSymbol *End) {
2796 Unit->addLabelAddress(D, dwarf::DW_AT_low_pc, Begin);
2797 if (DwarfVersion < 4)
2798 Unit->addLabelAddress(D, dwarf::DW_AT_high_pc, End);
2800 Unit->addLabelDelta(D, dwarf::DW_AT_high_pc, End, Begin);