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."),
64 GenerateGnuPubSections("generate-gnu-dwarf-pub-sections", cl::Hidden,
65 cl::desc("Generate GNU-style pubnames and pubtypes"),
68 static cl::opt<bool> GenerateARangeSection("generate-arange-section",
70 cl::desc("Generate dwarf aranges"),
74 enum DefaultOnOff { Default, Enable, Disable };
77 static cl::opt<DefaultOnOff>
78 DwarfAccelTables("dwarf-accel-tables", cl::Hidden,
79 cl::desc("Output prototype dwarf accelerator tables."),
80 cl::values(clEnumVal(Default, "Default for platform"),
81 clEnumVal(Enable, "Enabled"),
82 clEnumVal(Disable, "Disabled"), clEnumValEnd),
85 static cl::opt<DefaultOnOff>
86 SplitDwarf("split-dwarf", cl::Hidden,
87 cl::desc("Output DWARF5 split debug info."),
88 cl::values(clEnumVal(Default, "Default for platform"),
89 clEnumVal(Enable, "Enabled"),
90 clEnumVal(Disable, "Disabled"), clEnumValEnd),
93 static cl::opt<DefaultOnOff>
94 DwarfPubSections("generate-dwarf-pub-sections", cl::Hidden,
95 cl::desc("Generate DWARF pubnames and pubtypes sections"),
96 cl::values(clEnumVal(Default, "Default for platform"),
97 clEnumVal(Enable, "Enabled"),
98 clEnumVal(Disable, "Disabled"), clEnumValEnd),
101 static cl::opt<unsigned>
102 DwarfVersionNumber("dwarf-version", cl::Hidden,
103 cl::desc("Generate DWARF for dwarf version."), cl::init(0));
105 static const char *const DWARFGroupName = "DWARF Emission";
106 static const char *const DbgTimerName = "DWARF Debug Writer";
108 //===----------------------------------------------------------------------===//
112 /// resolve - Look in the DwarfDebug map for the MDNode that
113 /// corresponds to the reference.
114 template <typename T> T DbgVariable::resolve(DIRef<T> Ref) const {
115 return DD->resolve(Ref);
118 bool DbgVariable::isBlockByrefVariable() const {
119 assert(Var.isVariable() && "Invalid complex DbgVariable!");
120 return Var.isBlockByrefVariable(DD->getTypeIdentifierMap());
124 DIType DbgVariable::getType() const {
125 DIType Ty = Var.getType().resolve(DD->getTypeIdentifierMap());
126 // FIXME: isBlockByrefVariable should be reformulated in terms of complex
127 // addresses instead.
128 if (Var.isBlockByrefVariable(DD->getTypeIdentifierMap())) {
129 /* Byref variables, in Blocks, are declared by the programmer as
130 "SomeType VarName;", but the compiler creates a
131 __Block_byref_x_VarName struct, and gives the variable VarName
132 either the struct, or a pointer to the struct, as its type. This
133 is necessary for various behind-the-scenes things the compiler
134 needs to do with by-reference variables in blocks.
136 However, as far as the original *programmer* is concerned, the
137 variable should still have type 'SomeType', as originally declared.
139 The following function dives into the __Block_byref_x_VarName
140 struct to find the original type of the variable. This will be
141 passed back to the code generating the type for the Debug
142 Information Entry for the variable 'VarName'. 'VarName' will then
143 have the original type 'SomeType' in its debug information.
145 The original type 'SomeType' will be the type of the field named
146 'VarName' inside the __Block_byref_x_VarName struct.
148 NOTE: In order for this to not completely fail on the debugger
149 side, the Debug Information Entry for the variable VarName needs to
150 have a DW_AT_location that tells the debugger how to unwind through
151 the pointers and __Block_byref_x_VarName struct to find the actual
152 value of the variable. The function addBlockByrefType does this. */
154 uint16_t tag = Ty.getTag();
156 if (tag == dwarf::DW_TAG_pointer_type)
157 subType = resolve(DIDerivedType(Ty).getTypeDerivedFrom());
159 DIArray Elements = DICompositeType(subType).getTypeArray();
160 for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) {
161 DIDerivedType DT(Elements.getElement(i));
162 if (getName() == DT.getName())
163 return (resolve(DT.getTypeDerivedFrom()));
169 } // end llvm namespace
171 /// Return Dwarf Version by checking module flags.
172 static unsigned getDwarfVersionFromModule(const Module *M) {
173 Value *Val = M->getModuleFlag("Dwarf Version");
175 return dwarf::DWARF_VERSION;
176 return cast<ConstantInt>(Val)->getZExtValue();
179 DwarfDebug::DwarfDebug(AsmPrinter *A, Module *M)
180 : Asm(A), MMI(Asm->MMI), FirstCU(0), PrevLabel(NULL), GlobalRangeCount(0),
181 InfoHolder(A, "info_string", DIEValueAllocator),
182 UsedNonDefaultText(false),
183 SkeletonHolder(A, "skel_string", DIEValueAllocator) {
185 DwarfInfoSectionSym = DwarfAbbrevSectionSym = DwarfStrSectionSym = 0;
186 DwarfDebugRangeSectionSym = DwarfDebugLocSectionSym = DwarfLineSectionSym = 0;
187 DwarfAddrSectionSym = 0;
188 DwarfAbbrevDWOSectionSym = DwarfStrDWOSectionSym = 0;
189 FunctionBeginSym = FunctionEndSym = 0;
193 // Turn on accelerator tables for Darwin by default, pubnames by
194 // default for non-Darwin, and handle split dwarf.
195 bool IsDarwin = Triple(A->getTargetTriple()).isOSDarwin();
197 if (DwarfAccelTables == Default)
198 HasDwarfAccelTables = IsDarwin;
200 HasDwarfAccelTables = DwarfAccelTables == Enable;
202 if (SplitDwarf == Default)
203 HasSplitDwarf = false;
205 HasSplitDwarf = SplitDwarf == Enable;
207 if (DwarfPubSections == Default)
208 HasDwarfPubSections = !IsDarwin;
210 HasDwarfPubSections = DwarfPubSections == Enable;
212 DwarfVersion = DwarfVersionNumber
214 : getDwarfVersionFromModule(MMI->getModule());
217 NamedRegionTimer T(DbgTimerName, DWARFGroupName, TimePassesIsEnabled);
222 // Switch to the specified MCSection and emit an assembler
223 // temporary label to it if SymbolStem is specified.
224 static MCSymbol *emitSectionSym(AsmPrinter *Asm, const MCSection *Section,
225 const char *SymbolStem = 0) {
226 Asm->OutStreamer.SwitchSection(Section);
230 MCSymbol *TmpSym = Asm->GetTempSymbol(SymbolStem);
231 Asm->OutStreamer.EmitLabel(TmpSym);
235 DwarfFile::~DwarfFile() {
236 for (DwarfUnit *DU : CUs)
240 MCSymbol *DwarfFile::getStringPoolSym() {
241 return Asm->GetTempSymbol(StringPref);
244 MCSymbol *DwarfFile::getStringPoolEntry(StringRef Str) {
245 std::pair<MCSymbol *, unsigned> &Entry =
246 StringPool.GetOrCreateValue(Str).getValue();
250 Entry.second = NextStringPoolNumber++;
251 return Entry.first = Asm->GetTempSymbol(StringPref, Entry.second);
254 unsigned DwarfFile::getStringPoolIndex(StringRef Str) {
255 std::pair<MCSymbol *, unsigned> &Entry =
256 StringPool.GetOrCreateValue(Str).getValue();
260 Entry.second = NextStringPoolNumber++;
261 Entry.first = Asm->GetTempSymbol(StringPref, Entry.second);
265 unsigned DwarfFile::getAddrPoolIndex(const MCSymbol *Sym, bool TLS) {
266 std::pair<AddrPool::iterator, bool> P = AddressPool.insert(
267 std::make_pair(Sym, AddressPoolEntry(NextAddrPoolNumber, TLS)));
269 ++NextAddrPoolNumber;
270 return P.first->second.Number;
273 // Define a unique number for the abbreviation.
275 void DwarfFile::assignAbbrevNumber(DIEAbbrev &Abbrev) {
276 // Check the set for priors.
277 DIEAbbrev *InSet = AbbreviationsSet.GetOrInsertNode(&Abbrev);
279 // If it's newly added.
280 if (InSet == &Abbrev) {
281 // Add to abbreviation list.
282 Abbreviations.push_back(&Abbrev);
284 // Assign the vector position + 1 as its number.
285 Abbrev.setNumber(Abbreviations.size());
287 // Assign existing abbreviation number.
288 Abbrev.setNumber(InSet->getNumber());
292 static bool isObjCClass(StringRef Name) {
293 return Name.startswith("+") || Name.startswith("-");
296 static bool hasObjCCategory(StringRef Name) {
297 if (!isObjCClass(Name))
300 return Name.find(") ") != StringRef::npos;
303 static void getObjCClassCategory(StringRef In, StringRef &Class,
304 StringRef &Category) {
305 if (!hasObjCCategory(In)) {
306 Class = In.slice(In.find('[') + 1, In.find(' '));
311 Class = In.slice(In.find('[') + 1, In.find('('));
312 Category = In.slice(In.find('[') + 1, In.find(' '));
316 static StringRef getObjCMethodName(StringRef In) {
317 return In.slice(In.find(' ') + 1, In.find(']'));
320 // Helper for sorting sections into a stable output order.
321 static bool SectionSort(const MCSection *A, const MCSection *B) {
322 std::string LA = (A ? A->getLabelBeginName() : "");
323 std::string LB = (B ? B->getLabelBeginName() : "");
327 // Add the various names to the Dwarf accelerator table names.
328 // TODO: Determine whether or not we should add names for programs
329 // that do not have a DW_AT_name or DW_AT_linkage_name field - this
330 // is only slightly different than the lookup of non-standard ObjC names.
331 static void addSubprogramNames(DwarfUnit *TheU, DISubprogram SP, DIE *Die) {
332 if (!SP.isDefinition())
334 TheU->addAccelName(SP.getName(), Die);
336 // If the linkage name is different than the name, go ahead and output
337 // that as well into the name table.
338 if (SP.getLinkageName() != "" && SP.getName() != SP.getLinkageName())
339 TheU->addAccelName(SP.getLinkageName(), Die);
341 // If this is an Objective-C selector name add it to the ObjC accelerator
343 if (isObjCClass(SP.getName())) {
344 StringRef Class, Category;
345 getObjCClassCategory(SP.getName(), Class, Category);
346 TheU->addAccelObjC(Class, Die);
348 TheU->addAccelObjC(Category, Die);
349 // Also add the base method name to the name table.
350 TheU->addAccelName(getObjCMethodName(SP.getName()), Die);
354 /// isSubprogramContext - Return true if Context is either a subprogram
355 /// or another context nested inside a subprogram.
356 bool DwarfDebug::isSubprogramContext(const MDNode *Context) {
359 DIDescriptor D(Context);
360 if (D.isSubprogram())
363 return isSubprogramContext(resolve(DIType(Context).getContext()));
367 // Find DIE for the given subprogram and attach appropriate DW_AT_low_pc
368 // and DW_AT_high_pc attributes. If there are global variables in this
369 // scope then create and insert DIEs for these variables.
370 DIE *DwarfDebug::updateSubprogramScopeDIE(DwarfCompileUnit *SPCU,
372 DIE *SPDie = SPCU->getDIE(SP);
374 assert(SPDie && "Unable to find subprogram DIE!");
376 // If we're updating an abstract DIE, then we will be adding the children and
377 // object pointer later on. But what we don't want to do is process the
378 // concrete DIE twice.
379 if (DIE *AbsSPDIE = AbstractSPDies.lookup(SP)) {
380 // Pick up abstract subprogram DIE.
382 SPCU->createAndAddDIE(dwarf::DW_TAG_subprogram, *SPCU->getUnitDie());
383 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_abstract_origin, AbsSPDIE);
385 DISubprogram SPDecl = SP.getFunctionDeclaration();
386 if (!SPDecl.isSubprogram()) {
387 // There is not any need to generate specification DIE for a function
388 // defined at compile unit level. If a function is defined inside another
389 // function then gdb prefers the definition at top level and but does not
390 // expect specification DIE in parent function. So avoid creating
391 // specification DIE for a function defined inside a function.
392 DIScope SPContext = resolve(SP.getContext());
393 if (SP.isDefinition() && !SPContext.isCompileUnit() &&
394 !SPContext.isFile() && !isSubprogramContext(SPContext)) {
395 SPCU->addFlag(SPDie, dwarf::DW_AT_declaration);
398 DICompositeType SPTy = SP.getType();
399 DIArray Args = SPTy.getTypeArray();
400 uint16_t SPTag = SPTy.getTag();
401 if (SPTag == dwarf::DW_TAG_subroutine_type)
402 SPCU->constructSubprogramArguments(*SPDie, Args);
403 DIE *SPDeclDie = SPDie;
404 SPDie = SPCU->createAndAddDIE(dwarf::DW_TAG_subprogram,
405 *SPCU->getUnitDie());
406 SPCU->addDIEEntry(SPDie, dwarf::DW_AT_specification, SPDeclDie);
411 attachLowHighPC(SPCU, SPDie, FunctionBeginSym, FunctionEndSym);
413 const TargetRegisterInfo *RI = Asm->TM.getRegisterInfo();
414 MachineLocation Location(RI->getFrameRegister(*Asm->MF));
415 SPCU->addAddress(SPDie, dwarf::DW_AT_frame_base, Location);
417 // Add name to the name table, we do this here because we're guaranteed
418 // to have concrete versions of our DW_TAG_subprogram nodes.
419 addSubprogramNames(SPCU, SP, SPDie);
424 /// Check whether we should create a DIE for the given Scope, return true
425 /// if we don't create a DIE (the corresponding DIE is null).
426 bool DwarfDebug::isLexicalScopeDIENull(LexicalScope *Scope) {
427 if (Scope->isAbstractScope())
430 // We don't create a DIE if there is no Range.
431 const SmallVectorImpl<InsnRange> &Ranges = Scope->getRanges();
435 if (Ranges.size() > 1)
438 // We don't create a DIE if we have a single Range and the end label
440 SmallVectorImpl<InsnRange>::const_iterator RI = Ranges.begin();
441 MCSymbol *End = getLabelAfterInsn(RI->second);
445 static void addSectionLabel(AsmPrinter *Asm, DwarfUnit *U, DIE *D,
446 dwarf::Attribute A, const MCSymbol *L,
447 const MCSymbol *Sec) {
448 if (Asm->MAI->doesDwarfUseRelocationsAcrossSections())
449 U->addSectionLabel(D, A, L);
451 U->addSectionDelta(D, A, L, Sec);
454 void DwarfDebug::addScopeRangeList(DwarfCompileUnit *TheCU, DIE *ScopeDIE,
455 const SmallVectorImpl<InsnRange> &Range) {
456 // Emit offset in .debug_range as a relocatable label. emitDIE will handle
457 // emitting it appropriately.
458 MCSymbol *RangeSym = Asm->GetTempSymbol("debug_ranges", GlobalRangeCount++);
460 // Under fission, ranges are specified by constant offsets relative to the
461 // CU's DW_AT_GNU_ranges_base.
463 TheCU->addSectionDelta(ScopeDIE, dwarf::DW_AT_ranges, RangeSym,
464 DwarfDebugRangeSectionSym);
466 addSectionLabel(Asm, TheCU, ScopeDIE, dwarf::DW_AT_ranges, RangeSym,
467 DwarfDebugRangeSectionSym);
469 RangeSpanList List(RangeSym);
470 for (const InsnRange &R : Range) {
471 RangeSpan Span(getLabelBeforeInsn(R.first), getLabelAfterInsn(R.second));
472 List.addRange(std::move(Span));
475 // Add the range list to the set of ranges to be emitted.
476 TheCU->addRangeList(std::move(List));
479 // Construct new DW_TAG_lexical_block for this scope and attach
480 // DW_AT_low_pc/DW_AT_high_pc labels.
481 DIE *DwarfDebug::constructLexicalScopeDIE(DwarfCompileUnit *TheCU,
482 LexicalScope *Scope) {
483 if (isLexicalScopeDIENull(Scope))
486 DIE *ScopeDIE = new DIE(dwarf::DW_TAG_lexical_block);
487 if (Scope->isAbstractScope())
490 const SmallVectorImpl<InsnRange> &ScopeRanges = Scope->getRanges();
492 // If we have multiple ranges, emit them into the range section.
493 if (ScopeRanges.size() > 1) {
494 addScopeRangeList(TheCU, ScopeDIE, ScopeRanges);
498 // Construct the address range for this DIE.
499 SmallVectorImpl<InsnRange>::const_iterator RI = ScopeRanges.begin();
500 MCSymbol *Start = getLabelBeforeInsn(RI->first);
501 MCSymbol *End = getLabelAfterInsn(RI->second);
502 assert(End && "End label should not be null!");
504 assert(Start->isDefined() && "Invalid starting label for an inlined scope!");
505 assert(End->isDefined() && "Invalid end label for an inlined scope!");
507 attachLowHighPC(TheCU, ScopeDIE, Start, End);
512 // This scope represents inlined body of a function. Construct DIE to
513 // represent this concrete inlined copy of the function.
514 DIE *DwarfDebug::constructInlinedScopeDIE(DwarfCompileUnit *TheCU,
515 LexicalScope *Scope) {
516 const SmallVectorImpl<InsnRange> &ScopeRanges = Scope->getRanges();
517 assert(!ScopeRanges.empty() &&
518 "LexicalScope does not have instruction markers!");
520 if (!Scope->getScopeNode())
522 DIScope DS(Scope->getScopeNode());
523 DISubprogram InlinedSP = getDISubprogram(DS);
524 DIE *OriginDIE = TheCU->getDIE(InlinedSP);
526 DEBUG(dbgs() << "Unable to find original DIE for an inlined subprogram.");
530 DIE *ScopeDIE = new DIE(dwarf::DW_TAG_inlined_subroutine);
531 TheCU->addDIEEntry(ScopeDIE, dwarf::DW_AT_abstract_origin, OriginDIE);
533 // If we have multiple ranges, emit them into the range section.
534 if (ScopeRanges.size() > 1)
535 addScopeRangeList(TheCU, ScopeDIE, ScopeRanges);
537 SmallVectorImpl<InsnRange>::const_iterator RI = ScopeRanges.begin();
538 MCSymbol *StartLabel = getLabelBeforeInsn(RI->first);
539 MCSymbol *EndLabel = getLabelAfterInsn(RI->second);
541 if (StartLabel == 0 || EndLabel == 0)
542 llvm_unreachable("Unexpected Start and End labels for an inlined scope!");
544 assert(StartLabel->isDefined() &&
545 "Invalid starting label for an inlined scope!");
546 assert(EndLabel->isDefined() && "Invalid end label for an inlined scope!");
548 attachLowHighPC(TheCU, ScopeDIE, StartLabel, EndLabel);
551 InlinedSubprogramDIEs.insert(OriginDIE);
553 // Add the call site information to the DIE.
554 DILocation DL(Scope->getInlinedAt());
556 ScopeDIE, dwarf::DW_AT_call_file, None,
557 TheCU->getOrCreateSourceID(DL.getFilename(), DL.getDirectory()));
558 TheCU->addUInt(ScopeDIE, dwarf::DW_AT_call_line, None, DL.getLineNumber());
560 // Add name to the name table, we do this here because we're guaranteed
561 // to have concrete versions of our DW_TAG_inlined_subprogram nodes.
562 addSubprogramNames(TheCU, InlinedSP, ScopeDIE);
567 DIE *DwarfDebug::createScopeChildrenDIE(DwarfCompileUnit *TheCU,
569 SmallVectorImpl<DIE *> &Children) {
570 DIE *ObjectPointer = NULL;
572 // Collect arguments for current function.
573 if (LScopes.isCurrentFunctionScope(Scope)) {
574 for (DbgVariable *ArgDV : CurrentFnArguments)
577 TheCU->constructVariableDIE(*ArgDV, Scope->isAbstractScope())) {
578 Children.push_back(Arg);
579 if (ArgDV->isObjectPointer())
583 // If this is a variadic function, add an unspecified parameter.
584 DISubprogram SP(Scope->getScopeNode());
585 DIArray FnArgs = SP.getType().getTypeArray();
586 if (FnArgs.getElement(FnArgs.getNumElements() - 1)
587 .isUnspecifiedParameter()) {
588 DIE *Ellipsis = new DIE(dwarf::DW_TAG_unspecified_parameters);
589 Children.push_back(Ellipsis);
593 // Collect lexical scope children first.
594 for (DbgVariable *DV : ScopeVariables.lookup(Scope))
595 if (DIE *Variable = TheCU->constructVariableDIE(*DV,
596 Scope->isAbstractScope())) {
597 Children.push_back(Variable);
598 if (DV->isObjectPointer())
599 ObjectPointer = Variable;
601 for (LexicalScope *LS : Scope->getChildren())
602 if (DIE *Nested = constructScopeDIE(TheCU, LS))
603 Children.push_back(Nested);
604 return ObjectPointer;
607 // Construct a DIE for this scope.
608 DIE *DwarfDebug::constructScopeDIE(DwarfCompileUnit *TheCU,
609 LexicalScope *Scope) {
610 if (!Scope || !Scope->getScopeNode())
613 DIScope DS(Scope->getScopeNode());
615 SmallVector<DIE *, 8> Children;
616 DIE *ObjectPointer = NULL;
617 bool ChildrenCreated = false;
619 // We try to create the scope DIE first, then the children DIEs. This will
620 // avoid creating un-used children then removing them later when we find out
621 // the scope DIE is null.
622 DIE *ScopeDIE = NULL;
623 if (Scope->getInlinedAt())
624 ScopeDIE = constructInlinedScopeDIE(TheCU, Scope);
625 else if (DS.isSubprogram()) {
626 ProcessedSPNodes.insert(DS);
627 if (Scope->isAbstractScope()) {
628 ScopeDIE = TheCU->getDIE(DS);
629 // Note down abstract DIE.
631 AbstractSPDies.insert(std::make_pair(DS, ScopeDIE));
633 ScopeDIE = updateSubprogramScopeDIE(TheCU, DISubprogram(DS));
635 // Early exit when we know the scope DIE is going to be null.
636 if (isLexicalScopeDIENull(Scope))
639 // We create children here when we know the scope DIE is not going to be
640 // null and the children will be added to the scope DIE.
641 ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children);
642 ChildrenCreated = true;
644 // There is no need to emit empty lexical block DIE.
645 std::pair<ImportedEntityMap::const_iterator,
646 ImportedEntityMap::const_iterator> Range =
648 ScopesWithImportedEntities.begin(),
649 ScopesWithImportedEntities.end(),
650 std::pair<const MDNode *, const MDNode *>(DS, (const MDNode *)0),
652 if (Children.empty() && Range.first == Range.second)
654 ScopeDIE = constructLexicalScopeDIE(TheCU, Scope);
655 assert(ScopeDIE && "Scope DIE should not be null.");
656 for (ImportedEntityMap::const_iterator i = Range.first; i != Range.second;
658 constructImportedEntityDIE(TheCU, i->second, ScopeDIE);
662 assert(Children.empty() &&
663 "We create children only when the scope DIE is not null.");
666 if (!ChildrenCreated)
667 // We create children when the scope DIE is not null.
668 ObjectPointer = createScopeChildrenDIE(TheCU, Scope, Children);
671 for (DIE *I : Children)
672 ScopeDIE->addChild(I);
674 if (DS.isSubprogram() && ObjectPointer != NULL)
675 TheCU->addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, ObjectPointer);
680 void DwarfDebug::addGnuPubAttributes(DwarfUnit *U, DIE *D) const {
681 if (!GenerateGnuPubSections)
684 U->addFlag(D, dwarf::DW_AT_GNU_pubnames);
687 // Create new DwarfCompileUnit for the given metadata node with tag
688 // DW_TAG_compile_unit.
689 DwarfCompileUnit *DwarfDebug::constructDwarfCompileUnit(DICompileUnit DIUnit) {
690 StringRef FN = DIUnit.getFilename();
691 CompilationDir = DIUnit.getDirectory();
693 DIE *Die = new DIE(dwarf::DW_TAG_compile_unit);
694 DwarfCompileUnit *NewCU = new DwarfCompileUnit(
695 InfoHolder.getUnits().size(), Die, DIUnit, Asm, this, &InfoHolder);
696 InfoHolder.addUnit(NewCU);
698 // LTO with assembly output shares a single line table amongst multiple CUs.
699 // To avoid the compilation directory being ambiguous, let the line table
700 // explicitly describe the directory of all files, never relying on the
701 // compilation directory.
702 if (!Asm->OutStreamer.hasRawTextSupport() || SingleCU)
703 Asm->OutStreamer.getContext().setMCLineTableCompilationDir(
704 NewCU->getUniqueID(), CompilationDir);
706 NewCU->addString(Die, dwarf::DW_AT_producer, DIUnit.getProducer());
707 NewCU->addUInt(Die, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
708 DIUnit.getLanguage());
709 NewCU->addString(Die, dwarf::DW_AT_name, FN);
711 if (!useSplitDwarf()) {
712 NewCU->initStmtList(DwarfLineSectionSym);
714 // If we're using split dwarf the compilation dir is going to be in the
715 // skeleton CU and so we don't need to duplicate it here.
716 if (!CompilationDir.empty())
717 NewCU->addString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
719 addGnuPubAttributes(NewCU, Die);
722 if (DIUnit.isOptimized())
723 NewCU->addFlag(Die, dwarf::DW_AT_APPLE_optimized);
725 StringRef Flags = DIUnit.getFlags();
727 NewCU->addString(Die, dwarf::DW_AT_APPLE_flags, Flags);
729 if (unsigned RVer = DIUnit.getRunTimeVersion())
730 NewCU->addUInt(Die, dwarf::DW_AT_APPLE_major_runtime_vers,
731 dwarf::DW_FORM_data1, RVer);
736 if (useSplitDwarf()) {
737 NewCU->initSection(Asm->getObjFileLowering().getDwarfInfoDWOSection(),
738 DwarfInfoDWOSectionSym);
739 NewCU->setSkeleton(constructSkeletonCU(NewCU));
741 NewCU->initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
742 DwarfInfoSectionSym);
744 CUMap.insert(std::make_pair(DIUnit, NewCU));
745 CUDieMap.insert(std::make_pair(Die, NewCU));
749 // Construct subprogram DIE.
750 void DwarfDebug::constructSubprogramDIE(DwarfCompileUnit *TheCU,
752 // FIXME: We should only call this routine once, however, during LTO if a
753 // program is defined in multiple CUs we could end up calling it out of
754 // beginModule as we walk the CUs.
756 DwarfCompileUnit *&CURef = SPMap[N];
762 if (!SP.isDefinition())
763 // This is a method declaration which will be handled while constructing
767 DIE *SubprogramDie = TheCU->getOrCreateSubprogramDIE(SP);
769 // Expose as a global name.
770 TheCU->addGlobalName(SP.getName(), SubprogramDie, resolve(SP.getContext()));
773 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit *TheCU,
775 DIImportedEntity Module(N);
776 assert(Module.Verify());
777 if (DIE *D = TheCU->getOrCreateContextDIE(Module.getContext()))
778 constructImportedEntityDIE(TheCU, Module, D);
781 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit *TheCU,
782 const MDNode *N, DIE *Context) {
783 DIImportedEntity Module(N);
784 assert(Module.Verify());
785 return constructImportedEntityDIE(TheCU, Module, Context);
788 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit *TheCU,
789 const DIImportedEntity &Module,
791 assert(Module.Verify() &&
792 "Use one of the MDNode * overloads to handle invalid metadata");
793 assert(Context && "Should always have a context for an imported_module");
794 DIE *IMDie = new DIE(Module.getTag());
795 TheCU->insertDIE(Module, IMDie);
797 DIDescriptor Entity = resolve(Module.getEntity());
798 if (Entity.isNameSpace())
799 EntityDie = TheCU->getOrCreateNameSpace(DINameSpace(Entity));
800 else if (Entity.isSubprogram())
801 EntityDie = TheCU->getOrCreateSubprogramDIE(DISubprogram(Entity));
802 else if (Entity.isType())
803 EntityDie = TheCU->getOrCreateTypeDIE(DIType(Entity));
805 EntityDie = TheCU->getDIE(Entity);
806 TheCU->addSourceLine(IMDie, Module.getLineNumber(),
807 Module.getContext().getFilename(),
808 Module.getContext().getDirectory());
809 TheCU->addDIEEntry(IMDie, dwarf::DW_AT_import, EntityDie);
810 StringRef Name = Module.getName();
812 TheCU->addString(IMDie, dwarf::DW_AT_name, Name);
813 Context->addChild(IMDie);
816 // Emit all Dwarf sections that should come prior to the content. Create
817 // global DIEs and emit initial debug info sections. This is invoked by
818 // the target AsmPrinter.
819 void DwarfDebug::beginModule() {
820 if (DisableDebugInfoPrinting)
823 const Module *M = MMI->getModule();
825 // If module has named metadata anchors then use them, otherwise scan the
826 // module using debug info finder to collect debug info.
827 NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu");
830 TypeIdentifierMap = generateDITypeIdentifierMap(CU_Nodes);
832 // Emit initial sections so we can reference labels later.
835 SingleCU = CU_Nodes->getNumOperands() == 1;
837 for (MDNode *N : CU_Nodes->operands()) {
838 DICompileUnit CUNode(N);
839 DwarfCompileUnit *CU = constructDwarfCompileUnit(CUNode);
840 DIArray ImportedEntities = CUNode.getImportedEntities();
841 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
842 ScopesWithImportedEntities.push_back(std::make_pair(
843 DIImportedEntity(ImportedEntities.getElement(i)).getContext(),
844 ImportedEntities.getElement(i)));
845 std::sort(ScopesWithImportedEntities.begin(),
846 ScopesWithImportedEntities.end(), less_first());
847 DIArray GVs = CUNode.getGlobalVariables();
848 for (unsigned i = 0, e = GVs.getNumElements(); i != e; ++i)
849 CU->createGlobalVariableDIE(DIGlobalVariable(GVs.getElement(i)));
850 DIArray SPs = CUNode.getSubprograms();
851 for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i)
852 constructSubprogramDIE(CU, SPs.getElement(i));
853 DIArray EnumTypes = CUNode.getEnumTypes();
854 for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i)
855 CU->getOrCreateTypeDIE(EnumTypes.getElement(i));
856 DIArray RetainedTypes = CUNode.getRetainedTypes();
857 for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i) {
858 DIType Ty(RetainedTypes.getElement(i));
859 // The retained types array by design contains pointers to
860 // MDNodes rather than DIRefs. Unique them here.
861 DIType UniqueTy(resolve(Ty.getRef()));
862 CU->getOrCreateTypeDIE(UniqueTy);
864 // Emit imported_modules last so that the relevant context is already
866 for (unsigned i = 0, e = ImportedEntities.getNumElements(); i != e; ++i)
867 constructImportedEntityDIE(CU, ImportedEntities.getElement(i));
870 // Tell MMI that we have debug info.
871 MMI->setDebugInfoAvailability(true);
873 // Prime section data.
874 SectionMap[Asm->getObjFileLowering().getTextSection()];
877 // Attach DW_AT_inline attribute with inlined subprogram DIEs.
878 void DwarfDebug::computeInlinedDIEs() {
879 // Attach DW_AT_inline attribute with inlined subprogram DIEs.
880 for (DIE *ISP : InlinedSubprogramDIEs)
881 FirstCU->addUInt(ISP, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined);
883 for (const auto &AI : AbstractSPDies) {
884 DIE *ISP = AI.second;
885 if (InlinedSubprogramDIEs.count(ISP))
887 FirstCU->addUInt(ISP, dwarf::DW_AT_inline, None, dwarf::DW_INL_inlined);
891 // Collect info for variables that were optimized out.
892 void DwarfDebug::collectDeadVariables() {
893 const Module *M = MMI->getModule();
895 if (NamedMDNode *CU_Nodes = M->getNamedMetadata("llvm.dbg.cu")) {
896 for (MDNode *N : CU_Nodes->operands()) {
897 DICompileUnit TheCU(N);
898 DIArray Subprograms = TheCU.getSubprograms();
899 for (unsigned i = 0, e = Subprograms.getNumElements(); i != e; ++i) {
900 DISubprogram SP(Subprograms.getElement(i));
901 if (ProcessedSPNodes.count(SP) != 0)
903 if (!SP.isSubprogram())
905 if (!SP.isDefinition())
907 DIArray Variables = SP.getVariables();
908 if (Variables.getNumElements() == 0)
911 // Construct subprogram DIE and add variables DIEs.
912 DwarfCompileUnit *SPCU =
913 static_cast<DwarfCompileUnit *>(CUMap.lookup(TheCU));
914 assert(SPCU && "Unable to find Compile Unit!");
915 // FIXME: See the comment in constructSubprogramDIE about duplicate
917 constructSubprogramDIE(SPCU, SP);
918 DIE *SPDIE = SPCU->getDIE(SP);
919 for (unsigned vi = 0, ve = Variables.getNumElements(); vi != ve; ++vi) {
920 DIVariable DV(Variables.getElement(vi));
921 if (!DV.isVariable())
923 DbgVariable NewVar(DV, NULL, this);
924 if (DIE *VariableDIE = SPCU->constructVariableDIE(NewVar, false))
925 SPDIE->addChild(VariableDIE);
932 void DwarfDebug::finalizeModuleInfo() {
933 // Collect info for variables that were optimized out.
934 collectDeadVariables();
936 // Attach DW_AT_inline attribute with inlined subprogram DIEs.
937 computeInlinedDIEs();
939 // Handle anything that needs to be done on a per-unit basis after
940 // all other generation.
941 for (DwarfUnit *TheU : getUnits()) {
942 // Emit DW_AT_containing_type attribute to connect types with their
943 // vtable holding type.
944 TheU->constructContainingTypeDIEs();
946 // Add CU specific attributes if we need to add any.
947 if (TheU->getUnitDie()->getTag() == dwarf::DW_TAG_compile_unit) {
948 // If we're splitting the dwarf out now that we've got the entire
949 // CU then add the dwo id to it.
950 DwarfCompileUnit *SkCU =
951 static_cast<DwarfCompileUnit *>(TheU->getSkeleton());
952 if (useSplitDwarf()) {
953 // Emit a unique identifier for this CU.
954 uint64_t ID = DIEHash(Asm).computeCUSignature(*TheU->getUnitDie());
955 TheU->addUInt(TheU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
956 dwarf::DW_FORM_data8, ID);
957 SkCU->addUInt(SkCU->getUnitDie(), dwarf::DW_AT_GNU_dwo_id,
958 dwarf::DW_FORM_data8, ID);
960 // We don't keep track of which addresses are used in which CU so this
961 // is a bit pessimistic under LTO.
962 if (!InfoHolder.getAddrPool()->empty())
963 addSectionLabel(Asm, SkCU, SkCU->getUnitDie(),
964 dwarf::DW_AT_GNU_addr_base, DwarfAddrSectionSym,
965 DwarfAddrSectionSym);
966 if (!TheU->getRangeLists().empty())
967 addSectionLabel(Asm, SkCU, SkCU->getUnitDie(),
968 dwarf::DW_AT_GNU_ranges_base,
969 DwarfDebugRangeSectionSym, DwarfDebugRangeSectionSym);
972 // If we have code split among multiple sections or non-contiguous
973 // ranges of code then emit a DW_AT_ranges attribute on the unit that will
974 // remain in the .o file, otherwise add a DW_AT_low_pc.
975 // FIXME: We should use ranges allow reordering of code ala
976 // .subsections_via_symbols in mach-o. This would mean turning on
977 // ranges for all subprogram DIEs for mach-o.
978 DwarfCompileUnit *U = SkCU ? SkCU : static_cast<DwarfCompileUnit *>(TheU);
979 unsigned NumRanges = TheU->getRanges().size();
982 addSectionLabel(Asm, U, U->getUnitDie(), dwarf::DW_AT_ranges,
983 Asm->GetTempSymbol("cu_ranges", U->getUniqueID()),
984 DwarfDebugRangeSectionSym);
986 // A DW_AT_low_pc attribute may also be specified in combination with
987 // DW_AT_ranges to specify the default base address for use in
988 // location lists (see Section 2.6.2) and range lists (see Section
990 U->addUInt(U->getUnitDie(), dwarf::DW_AT_low_pc, dwarf::DW_FORM_addr,
993 RangeSpan &Range = TheU->getRanges().back();
994 U->addLocalLabelAddress(U->getUnitDie(), dwarf::DW_AT_low_pc,
996 U->addLabelDelta(U->getUnitDie(), dwarf::DW_AT_high_pc,
997 Range.getEnd(), Range.getStart());
1003 // Compute DIE offsets and sizes.
1004 InfoHolder.computeSizeAndOffsets();
1005 if (useSplitDwarf())
1006 SkeletonHolder.computeSizeAndOffsets();
1009 void DwarfDebug::endSections() {
1010 // Filter labels by section.
1011 for (const SymbolCU &SCU : ArangeLabels) {
1012 if (SCU.Sym->isInSection()) {
1013 // Make a note of this symbol and it's section.
1014 const MCSection *Section = &SCU.Sym->getSection();
1015 if (!Section->getKind().isMetadata())
1016 SectionMap[Section].push_back(SCU);
1018 // Some symbols (e.g. common/bss on mach-o) can have no section but still
1019 // appear in the output. This sucks as we rely on sections to build
1020 // arange spans. We can do it without, but it's icky.
1021 SectionMap[NULL].push_back(SCU);
1025 // Build a list of sections used.
1026 std::vector<const MCSection *> Sections;
1027 for (const auto &it : SectionMap) {
1028 const MCSection *Section = it.first;
1029 Sections.push_back(Section);
1032 // Sort the sections into order.
1033 // This is only done to ensure consistent output order across different runs.
1034 std::sort(Sections.begin(), Sections.end(), SectionSort);
1036 // Add terminating symbols for each section.
1037 for (unsigned ID = 0, E = Sections.size(); ID != E; ID++) {
1038 const MCSection *Section = Sections[ID];
1039 MCSymbol *Sym = NULL;
1042 // We can't call MCSection::getLabelEndName, as it's only safe to do so
1043 // if we know the section name up-front. For user-created sections, the
1044 // resulting label may not be valid to use as a label. (section names can
1045 // use a greater set of characters on some systems)
1046 Sym = Asm->GetTempSymbol("debug_end", ID);
1047 Asm->OutStreamer.SwitchSection(Section);
1048 Asm->OutStreamer.EmitLabel(Sym);
1051 // Insert a final terminator.
1052 SectionMap[Section].push_back(SymbolCU(NULL, Sym));
1056 // Emit all Dwarf sections that should come after the content.
1057 void DwarfDebug::endModule() {
1064 // End any existing sections.
1065 // TODO: Does this need to happen?
1068 // Finalize the debug info for the module.
1069 finalizeModuleInfo();
1073 // Emit all the DIEs into a debug info section.
1076 // Corresponding abbreviations into a abbrev section.
1077 emitAbbreviations();
1079 // Emit info into a debug aranges section.
1080 if (GenerateARangeSection)
1083 // Emit info into a debug ranges section.
1086 if (useSplitDwarf()) {
1089 emitDebugAbbrevDWO();
1091 // Emit DWO addresses.
1092 InfoHolder.emitAddresses(Asm->getObjFileLowering().getDwarfAddrSection());
1095 // Emit info into a debug loc section.
1098 // Emit info into the dwarf accelerator table sections.
1099 if (useDwarfAccelTables()) {
1102 emitAccelNamespaces();
1106 // Emit the pubnames and pubtypes sections if requested.
1107 if (HasDwarfPubSections) {
1108 emitDebugPubNames(GenerateGnuPubSections);
1109 emitDebugPubTypes(GenerateGnuPubSections);
1115 // Reset these for the next Module if we have one.
1119 // Find abstract variable, if any, associated with Var.
1120 DbgVariable *DwarfDebug::findAbstractVariable(DIVariable &DV,
1121 DebugLoc ScopeLoc) {
1122 LLVMContext &Ctx = DV->getContext();
1123 // More then one inlined variable corresponds to one abstract variable.
1124 DIVariable Var = cleanseInlinedVariable(DV, Ctx);
1125 DbgVariable *AbsDbgVariable = AbstractVariables.lookup(Var);
1127 return AbsDbgVariable;
1129 LexicalScope *Scope = LScopes.findAbstractScope(ScopeLoc.getScope(Ctx));
1133 AbsDbgVariable = new DbgVariable(Var, NULL, this);
1134 addScopeVariable(Scope, AbsDbgVariable);
1135 AbstractVariables[Var] = AbsDbgVariable;
1136 return AbsDbgVariable;
1139 // If Var is a current function argument then add it to CurrentFnArguments list.
1140 bool DwarfDebug::addCurrentFnArgument(DbgVariable *Var, LexicalScope *Scope) {
1141 if (!LScopes.isCurrentFunctionScope(Scope))
1143 DIVariable DV = Var->getVariable();
1144 if (DV.getTag() != dwarf::DW_TAG_arg_variable)
1146 unsigned ArgNo = DV.getArgNumber();
1150 size_t Size = CurrentFnArguments.size();
1152 CurrentFnArguments.resize(CurFn->getFunction()->arg_size());
1153 // llvm::Function argument size is not good indicator of how many
1154 // arguments does the function have at source level.
1156 CurrentFnArguments.resize(ArgNo * 2);
1157 CurrentFnArguments[ArgNo - 1] = Var;
1161 // Collect variable information from side table maintained by MMI.
1162 void DwarfDebug::collectVariableInfoFromMMITable(
1163 SmallPtrSet<const MDNode *, 16> &Processed) {
1164 for (const auto &VI : MMI->getVariableDbgInfo()) {
1167 Processed.insert(VI.Var);
1168 DIVariable DV(VI.Var);
1169 LexicalScope *Scope = LScopes.findLexicalScope(VI.Loc);
1171 // If variable scope is not found then skip this variable.
1175 DbgVariable *AbsDbgVariable = findAbstractVariable(DV, VI.Loc);
1176 DbgVariable *RegVar = new DbgVariable(DV, AbsDbgVariable, this);
1177 RegVar->setFrameIndex(VI.Slot);
1178 if (!addCurrentFnArgument(RegVar, Scope))
1179 addScopeVariable(Scope, RegVar);
1181 AbsDbgVariable->setFrameIndex(VI.Slot);
1185 // Return true if debug value, encoded by DBG_VALUE instruction, is in a
1187 static bool isDbgValueInDefinedReg(const MachineInstr *MI) {
1188 assert(MI->isDebugValue() && "Invalid DBG_VALUE machine instruction!");
1189 return MI->getNumOperands() == 3 && MI->getOperand(0).isReg() &&
1190 MI->getOperand(0).getReg() &&
1191 (MI->getOperand(1).isImm() ||
1192 (MI->getOperand(1).isReg() && MI->getOperand(1).getReg() == 0U));
1195 // Get .debug_loc entry for the instruction range starting at MI.
1196 static DebugLocEntry getDebugLocEntry(AsmPrinter *Asm,
1197 const MCSymbol *FLabel,
1198 const MCSymbol *SLabel,
1199 const MachineInstr *MI,
1200 DwarfCompileUnit *Unit) {
1201 const MDNode *Var = MI->getOperand(MI->getNumOperands() - 1).getMetadata();
1203 assert(MI->getNumOperands() == 3);
1204 if (MI->getOperand(0).isReg()) {
1205 MachineLocation MLoc;
1206 // If the second operand is an immediate, this is a
1207 // register-indirect address.
1208 if (!MI->getOperand(1).isImm())
1209 MLoc.set(MI->getOperand(0).getReg());
1211 MLoc.set(MI->getOperand(0).getReg(), MI->getOperand(1).getImm());
1212 return DebugLocEntry(FLabel, SLabel, MLoc, Var, Unit);
1214 if (MI->getOperand(0).isImm())
1215 return DebugLocEntry(FLabel, SLabel, MI->getOperand(0).getImm(), Unit);
1216 if (MI->getOperand(0).isFPImm())
1217 return DebugLocEntry(FLabel, SLabel, MI->getOperand(0).getFPImm(), Unit);
1218 if (MI->getOperand(0).isCImm())
1219 return DebugLocEntry(FLabel, SLabel, MI->getOperand(0).getCImm(), Unit);
1221 llvm_unreachable("Unexpected 3 operand DBG_VALUE instruction!");
1224 // Find variables for each lexical scope.
1226 DwarfDebug::collectVariableInfo(SmallPtrSet<const MDNode *, 16> &Processed) {
1228 // Grab the variable info that was squirreled away in the MMI side-table.
1229 collectVariableInfoFromMMITable(Processed);
1231 for (const MDNode *Var : UserVariables) {
1232 if (Processed.count(Var))
1235 // History contains relevant DBG_VALUE instructions for Var and instructions
1237 SmallVectorImpl<const MachineInstr *> &History = DbgValues[Var];
1238 if (History.empty())
1240 const MachineInstr *MInsn = History.front();
1243 LexicalScope *Scope = NULL;
1244 if (DV.getTag() == dwarf::DW_TAG_arg_variable &&
1245 DISubprogram(DV.getContext()).describes(CurFn->getFunction()))
1246 Scope = LScopes.getCurrentFunctionScope();
1247 else if (MDNode *IA = DV.getInlinedAt())
1248 Scope = LScopes.findInlinedScope(DebugLoc::getFromDILocation(IA));
1250 Scope = LScopes.findLexicalScope(cast<MDNode>(DV->getOperand(1)));
1251 // If variable scope is not found then skip this variable.
1255 Processed.insert(DV);
1256 assert(MInsn->isDebugValue() && "History must begin with debug value");
1257 DbgVariable *AbsVar = findAbstractVariable(DV, MInsn->getDebugLoc());
1258 DbgVariable *RegVar = new DbgVariable(DV, AbsVar, this);
1259 if (!addCurrentFnArgument(RegVar, Scope))
1260 addScopeVariable(Scope, RegVar);
1262 AbsVar->setMInsn(MInsn);
1264 // Simplify ranges that are fully coalesced.
1265 if (History.size() <= 1 ||
1266 (History.size() == 2 && MInsn->isIdenticalTo(History.back()))) {
1267 RegVar->setMInsn(MInsn);
1271 // Handle multiple DBG_VALUE instructions describing one variable.
1272 RegVar->setDotDebugLocOffset(DotDebugLocEntries.size());
1274 DotDebugLocEntries.resize(DotDebugLocEntries.size() + 1);
1275 DebugLocList &LocList = DotDebugLocEntries.back();
1277 Asm->GetTempSymbol("debug_loc", DotDebugLocEntries.size() - 1);
1278 SmallVector<DebugLocEntry, 4> &DebugLoc = LocList.List;
1279 for (SmallVectorImpl<const MachineInstr *>::const_iterator
1280 HI = History.begin(),
1283 const MachineInstr *Begin = *HI;
1284 assert(Begin->isDebugValue() && "Invalid History entry");
1286 // Check if DBG_VALUE is truncating a range.
1287 if (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() &&
1288 !Begin->getOperand(0).getReg())
1291 // Compute the range for a register location.
1292 const MCSymbol *FLabel = getLabelBeforeInsn(Begin);
1293 const MCSymbol *SLabel = 0;
1296 // If Begin is the last instruction in History then its value is valid
1297 // until the end of the function.
1298 SLabel = FunctionEndSym;
1300 const MachineInstr *End = HI[1];
1301 DEBUG(dbgs() << "DotDebugLoc Pair:\n"
1302 << "\t" << *Begin << "\t" << *End << "\n");
1303 if (End->isDebugValue())
1304 SLabel = getLabelBeforeInsn(End);
1306 // End is a normal instruction clobbering the range.
1307 SLabel = getLabelAfterInsn(End);
1308 assert(SLabel && "Forgot label after clobber instruction");
1313 // The value is valid until the next DBG_VALUE or clobber.
1314 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1315 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1316 DebugLocEntry Loc = getDebugLocEntry(Asm, FLabel, SLabel, Begin, TheCU);
1317 if (DebugLoc.empty() || !DebugLoc.back().Merge(Loc))
1318 DebugLoc.push_back(std::move(Loc));
1322 // Collect info for variables that were optimized out.
1323 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1324 DIArray Variables = DISubprogram(FnScope->getScopeNode()).getVariables();
1325 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1326 DIVariable DV(Variables.getElement(i));
1327 if (!DV || !DV.isVariable() || !Processed.insert(DV))
1329 if (LexicalScope *Scope = LScopes.findLexicalScope(DV.getContext()))
1330 addScopeVariable(Scope, new DbgVariable(DV, NULL, this));
1334 // Return Label preceding the instruction.
1335 MCSymbol *DwarfDebug::getLabelBeforeInsn(const MachineInstr *MI) {
1336 MCSymbol *Label = LabelsBeforeInsn.lookup(MI);
1337 assert(Label && "Didn't insert label before instruction");
1341 // Return Label immediately following the instruction.
1342 MCSymbol *DwarfDebug::getLabelAfterInsn(const MachineInstr *MI) {
1343 return LabelsAfterInsn.lookup(MI);
1346 // Process beginning of an instruction.
1347 void DwarfDebug::beginInstruction(const MachineInstr *MI) {
1350 // Check if source location changes, but ignore DBG_VALUE locations.
1351 if (!MI->isDebugValue()) {
1352 DebugLoc DL = MI->getDebugLoc();
1353 if (DL != PrevInstLoc && (!DL.isUnknown() || UnknownLocations)) {
1356 if (DL == PrologEndLoc) {
1357 Flags |= DWARF2_FLAG_PROLOGUE_END;
1358 PrologEndLoc = DebugLoc();
1360 if (PrologEndLoc.isUnknown())
1361 Flags |= DWARF2_FLAG_IS_STMT;
1363 if (!DL.isUnknown()) {
1364 const MDNode *Scope = DL.getScope(Asm->MF->getFunction()->getContext());
1365 recordSourceLine(DL.getLine(), DL.getCol(), Scope, Flags);
1367 recordSourceLine(0, 0, 0, 0);
1371 // Insert labels where requested.
1372 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1373 LabelsBeforeInsn.find(MI);
1376 if (I == LabelsBeforeInsn.end())
1379 // Label already assigned.
1384 PrevLabel = MMI->getContext().CreateTempSymbol();
1385 Asm->OutStreamer.EmitLabel(PrevLabel);
1387 I->second = PrevLabel;
1390 // Process end of an instruction.
1391 void DwarfDebug::endInstruction() {
1393 // Don't create a new label after DBG_VALUE instructions.
1394 // They don't generate code.
1395 if (!CurMI->isDebugValue())
1398 DenseMap<const MachineInstr *, MCSymbol *>::iterator I =
1399 LabelsAfterInsn.find(CurMI);
1403 if (I == LabelsAfterInsn.end())
1406 // Label already assigned.
1410 // We need a label after this instruction.
1412 PrevLabel = MMI->getContext().CreateTempSymbol();
1413 Asm->OutStreamer.EmitLabel(PrevLabel);
1415 I->second = PrevLabel;
1418 // Each LexicalScope has first instruction and last instruction to mark
1419 // beginning and end of a scope respectively. Create an inverse map that list
1420 // scopes starts (and ends) with an instruction. One instruction may start (or
1421 // end) multiple scopes. Ignore scopes that are not reachable.
1422 void DwarfDebug::identifyScopeMarkers() {
1423 SmallVector<LexicalScope *, 4> WorkList;
1424 WorkList.push_back(LScopes.getCurrentFunctionScope());
1425 while (!WorkList.empty()) {
1426 LexicalScope *S = WorkList.pop_back_val();
1428 const SmallVectorImpl<LexicalScope *> &Children = S->getChildren();
1429 if (!Children.empty())
1430 WorkList.append(Children.begin(), Children.end());
1432 if (S->isAbstractScope())
1435 for (const InsnRange &R : S->getRanges()) {
1436 assert(R.first && "InsnRange does not have first instruction!");
1437 assert(R.second && "InsnRange does not have second instruction!");
1438 requestLabelBeforeInsn(R.first);
1439 requestLabelAfterInsn(R.second);
1444 // Gather pre-function debug information. Assumes being called immediately
1445 // after the function entry point has been emitted.
1446 void DwarfDebug::beginFunction(const MachineFunction *MF) {
1449 // If there's no debug info for the function we're not going to do anything.
1450 if (!MMI->hasDebugInfo())
1453 // Grab the lexical scopes for the function, if we don't have any of those
1454 // then we're not going to be able to do anything.
1455 LScopes.initialize(*MF);
1456 if (LScopes.empty())
1459 assert(UserVariables.empty() && DbgValues.empty() && "Maps weren't cleaned");
1461 // Make sure that each lexical scope will have a begin/end label.
1462 identifyScopeMarkers();
1464 // Set DwarfDwarfCompileUnitID in MCContext to the Compile Unit this function
1465 // belongs to so that we add to the correct per-cu line table in the
1467 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1468 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1469 assert(TheCU && "Unable to find compile unit!");
1470 if (Asm->OutStreamer.hasRawTextSupport())
1471 // Use a single line table if we are generating assembly.
1472 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1474 Asm->OutStreamer.getContext().setDwarfCompileUnitID(TheCU->getUniqueID());
1476 // Emit a label for the function so that we have a beginning address.
1477 FunctionBeginSym = Asm->GetTempSymbol("func_begin", Asm->getFunctionNumber());
1478 // Assumes in correct section after the entry point.
1479 Asm->OutStreamer.EmitLabel(FunctionBeginSym);
1481 const TargetRegisterInfo *TRI = Asm->TM.getRegisterInfo();
1482 // LiveUserVar - Map physreg numbers to the MDNode they contain.
1483 std::vector<const MDNode *> LiveUserVar(TRI->getNumRegs());
1485 for (MachineFunction::const_iterator I = MF->begin(), E = MF->end(); I != E;
1487 bool AtBlockEntry = true;
1488 for (MachineBasicBlock::const_iterator II = I->begin(), IE = I->end();
1490 const MachineInstr *MI = II;
1492 if (MI->isDebugValue()) {
1493 assert(MI->getNumOperands() > 1 && "Invalid machine instruction!");
1495 // Keep track of user variables.
1497 MI->getOperand(MI->getNumOperands() - 1).getMetadata();
1499 // Variable is in a register, we need to check for clobbers.
1500 if (isDbgValueInDefinedReg(MI))
1501 LiveUserVar[MI->getOperand(0).getReg()] = Var;
1503 // Check the history of this variable.
1504 SmallVectorImpl<const MachineInstr *> &History = DbgValues[Var];
1505 if (History.empty()) {
1506 UserVariables.push_back(Var);
1507 // The first mention of a function argument gets the FunctionBeginSym
1508 // label, so arguments are visible when breaking at function entry.
1510 if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable &&
1511 getDISubprogram(DV.getContext()).describes(MF->getFunction()))
1512 LabelsBeforeInsn[MI] = FunctionBeginSym;
1514 // We have seen this variable before. Try to coalesce DBG_VALUEs.
1515 const MachineInstr *Prev = History.back();
1516 if (Prev->isDebugValue()) {
1517 // Coalesce identical entries at the end of History.
1518 if (History.size() >= 2 &&
1519 Prev->isIdenticalTo(History[History.size() - 2])) {
1520 DEBUG(dbgs() << "Coalescing identical DBG_VALUE entries:\n"
1521 << "\t" << *Prev << "\t"
1522 << *History[History.size() - 2] << "\n");
1526 // Terminate old register assignments that don't reach MI;
1527 MachineFunction::const_iterator PrevMBB = Prev->getParent();
1528 if (PrevMBB != I && (!AtBlockEntry || std::next(PrevMBB) != I) &&
1529 isDbgValueInDefinedReg(Prev)) {
1530 // Previous register assignment needs to terminate at the end of
1532 MachineBasicBlock::const_iterator LastMI =
1533 PrevMBB->getLastNonDebugInstr();
1534 if (LastMI == PrevMBB->end()) {
1535 // Drop DBG_VALUE for empty range.
1536 DEBUG(dbgs() << "Dropping DBG_VALUE for empty range:\n"
1537 << "\t" << *Prev << "\n");
1539 } else if (std::next(PrevMBB) != PrevMBB->getParent()->end())
1540 // Terminate after LastMI.
1541 History.push_back(LastMI);
1545 History.push_back(MI);
1547 // Not a DBG_VALUE instruction.
1548 if (!MI->isPosition())
1549 AtBlockEntry = false;
1551 // First known non-DBG_VALUE and non-frame setup location marks
1552 // the beginning of the function body.
1553 if (!MI->getFlag(MachineInstr::FrameSetup) &&
1554 (PrologEndLoc.isUnknown() && !MI->getDebugLoc().isUnknown()))
1555 PrologEndLoc = MI->getDebugLoc();
1557 // Check if the instruction clobbers any registers with debug vars.
1558 for (const MachineOperand &MO : MI->operands()) {
1559 if (!MO.isReg() || !MO.isDef() || !MO.getReg())
1561 for (MCRegAliasIterator AI(MO.getReg(), TRI, true); AI.isValid();
1564 const MDNode *Var = LiveUserVar[Reg];
1567 // Reg is now clobbered.
1568 LiveUserVar[Reg] = 0;
1570 // Was MD last defined by a DBG_VALUE referring to Reg?
1571 DbgValueHistoryMap::iterator HistI = DbgValues.find(Var);
1572 if (HistI == DbgValues.end())
1574 SmallVectorImpl<const MachineInstr *> &History = HistI->second;
1575 if (History.empty())
1577 const MachineInstr *Prev = History.back();
1578 // Sanity-check: Register assignments are terminated at the end of
1580 if (!Prev->isDebugValue() || Prev->getParent() != MI->getParent())
1582 // Is the variable still in Reg?
1583 if (!isDbgValueInDefinedReg(Prev) ||
1584 Prev->getOperand(0).getReg() != Reg)
1586 // Var is clobbered. Make sure the next instruction gets a label.
1587 History.push_back(MI);
1594 for (auto &I : DbgValues) {
1595 SmallVectorImpl<const MachineInstr *> &History = I.second;
1596 if (History.empty())
1599 // Make sure the final register assignments are terminated.
1600 const MachineInstr *Prev = History.back();
1601 if (Prev->isDebugValue() && isDbgValueInDefinedReg(Prev)) {
1602 const MachineBasicBlock *PrevMBB = Prev->getParent();
1603 MachineBasicBlock::const_iterator LastMI =
1604 PrevMBB->getLastNonDebugInstr();
1605 if (LastMI == PrevMBB->end())
1606 // Drop DBG_VALUE for empty range.
1608 else if (PrevMBB != &PrevMBB->getParent()->back()) {
1609 // Terminate after LastMI.
1610 History.push_back(LastMI);
1613 // Request labels for the full history.
1614 for (const MachineInstr *MI : History) {
1615 if (MI->isDebugValue())
1616 requestLabelBeforeInsn(MI);
1618 requestLabelAfterInsn(MI);
1622 PrevInstLoc = DebugLoc();
1623 PrevLabel = FunctionBeginSym;
1625 // Record beginning of function.
1626 if (!PrologEndLoc.isUnknown()) {
1627 DebugLoc FnStartDL =
1628 PrologEndLoc.getFnDebugLoc(MF->getFunction()->getContext());
1630 FnStartDL.getLine(), FnStartDL.getCol(),
1631 FnStartDL.getScope(MF->getFunction()->getContext()),
1632 // We'd like to list the prologue as "not statements" but GDB behaves
1633 // poorly if we do that. Revisit this with caution/GDB (7.5+) testing.
1634 DWARF2_FLAG_IS_STMT);
1638 void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) {
1639 SmallVectorImpl<DbgVariable *> &Vars = ScopeVariables[LS];
1640 DIVariable DV = Var->getVariable();
1641 // Variables with positive arg numbers are parameters.
1642 if (unsigned ArgNum = DV.getArgNumber()) {
1643 // Keep all parameters in order at the start of the variable list to ensure
1644 // function types are correct (no out-of-order parameters)
1646 // This could be improved by only doing it for optimized builds (unoptimized
1647 // builds have the right order to begin with), searching from the back (this
1648 // would catch the unoptimized case quickly), or doing a binary search
1649 // rather than linear search.
1650 SmallVectorImpl<DbgVariable *>::iterator I = Vars.begin();
1651 while (I != Vars.end()) {
1652 unsigned CurNum = (*I)->getVariable().getArgNumber();
1653 // A local (non-parameter) variable has been found, insert immediately
1657 // A later indexed parameter has been found, insert immediately before it.
1658 if (CurNum > ArgNum)
1662 Vars.insert(I, Var);
1666 Vars.push_back(Var);
1669 // Gather and emit post-function debug information.
1670 void DwarfDebug::endFunction(const MachineFunction *MF) {
1671 // Every beginFunction(MF) call should be followed by an endFunction(MF) call,
1672 // though the beginFunction may not be called at all.
1673 // We should handle both cases.
1677 assert(CurFn == MF);
1680 if (!MMI->hasDebugInfo() || LScopes.empty()) {
1681 // If we don't have a lexical scope for this function then there will
1682 // be a hole in the range information. Keep note of this by setting the
1683 // previously used section to nullptr.
1684 PrevSection = nullptr;
1690 // Define end label for subprogram.
1691 FunctionEndSym = Asm->GetTempSymbol("func_end", Asm->getFunctionNumber());
1692 // Assumes in correct section after the entry point.
1693 Asm->OutStreamer.EmitLabel(FunctionEndSym);
1695 // Set DwarfDwarfCompileUnitID in MCContext to default value.
1696 Asm->OutStreamer.getContext().setDwarfCompileUnitID(0);
1698 SmallPtrSet<const MDNode *, 16> ProcessedVars;
1699 collectVariableInfo(ProcessedVars);
1701 LexicalScope *FnScope = LScopes.getCurrentFunctionScope();
1702 DwarfCompileUnit *TheCU = SPMap.lookup(FnScope->getScopeNode());
1703 assert(TheCU && "Unable to find compile unit!");
1705 // Construct abstract scopes.
1706 for (LexicalScope *AScope : LScopes.getAbstractScopesList()) {
1707 DISubprogram SP(AScope->getScopeNode());
1708 if (SP.isSubprogram()) {
1709 // Collect info for variables that were optimized out.
1710 DIArray Variables = SP.getVariables();
1711 for (unsigned i = 0, e = Variables.getNumElements(); i != e; ++i) {
1712 DIVariable DV(Variables.getElement(i));
1713 if (!DV || !DV.isVariable() || !ProcessedVars.insert(DV))
1715 // Check that DbgVariable for DV wasn't created earlier, when
1716 // findAbstractVariable() was called for inlined instance of DV.
1717 LLVMContext &Ctx = DV->getContext();
1718 DIVariable CleanDV = cleanseInlinedVariable(DV, Ctx);
1719 if (AbstractVariables.lookup(CleanDV))
1721 if (LexicalScope *Scope = LScopes.findAbstractScope(DV.getContext()))
1722 addScopeVariable(Scope, new DbgVariable(DV, NULL, this));
1725 if (ProcessedSPNodes.count(AScope->getScopeNode()) == 0)
1726 constructScopeDIE(TheCU, AScope);
1729 DIE *CurFnDIE = constructScopeDIE(TheCU, FnScope);
1730 if (!CurFn->getTarget().Options.DisableFramePointerElim(*CurFn))
1731 TheCU->addFlag(CurFnDIE, dwarf::DW_AT_APPLE_omit_frame_ptr);
1733 // Add the range of this function to the list of ranges for the CU.
1734 RangeSpan Span(FunctionBeginSym, FunctionEndSym);
1735 TheCU->addRange(std::move(Span));
1736 PrevSection = Asm->getCurrentSection();
1740 for (auto &I : ScopeVariables)
1741 DeleteContainerPointers(I.second);
1742 ScopeVariables.clear();
1743 DeleteContainerPointers(CurrentFnArguments);
1744 UserVariables.clear();
1746 AbstractVariables.clear();
1747 LabelsBeforeInsn.clear();
1748 LabelsAfterInsn.clear();
1753 // Register a source line with debug info. Returns the unique label that was
1754 // emitted and which provides correspondence to the source line list.
1755 void DwarfDebug::recordSourceLine(unsigned Line, unsigned Col, const MDNode *S,
1760 unsigned Discriminator = 0;
1762 DIDescriptor Scope(S);
1764 if (Scope.isCompileUnit()) {
1765 DICompileUnit CU(S);
1766 Fn = CU.getFilename();
1767 Dir = CU.getDirectory();
1768 } else if (Scope.isFile()) {
1770 Fn = F.getFilename();
1771 Dir = F.getDirectory();
1772 } else if (Scope.isSubprogram()) {
1774 Fn = SP.getFilename();
1775 Dir = SP.getDirectory();
1776 } else if (Scope.isLexicalBlockFile()) {
1777 DILexicalBlockFile DBF(S);
1778 Fn = DBF.getFilename();
1779 Dir = DBF.getDirectory();
1780 } else if (Scope.isLexicalBlock()) {
1781 DILexicalBlock DB(S);
1782 Fn = DB.getFilename();
1783 Dir = DB.getDirectory();
1784 Discriminator = DB.getDiscriminator();
1786 llvm_unreachable("Unexpected scope info");
1788 unsigned CUID = Asm->OutStreamer.getContext().getDwarfCompileUnitID();
1789 Src = static_cast<DwarfCompileUnit *>(InfoHolder.getUnits()[CUID])
1790 ->getOrCreateSourceID(Fn, Dir);
1792 Asm->OutStreamer.EmitDwarfLocDirective(Src, Line, Col, Flags, 0,
1796 //===----------------------------------------------------------------------===//
1798 //===----------------------------------------------------------------------===//
1800 // Compute the size and offset of a DIE. The offset is relative to start of the
1801 // CU. It returns the offset after laying out the DIE.
1802 unsigned DwarfFile::computeSizeAndOffset(DIE *Die, unsigned Offset) {
1803 // Record the abbreviation.
1804 assignAbbrevNumber(Die->getAbbrev());
1806 // Get the abbreviation for this DIE.
1807 const DIEAbbrev &Abbrev = Die->getAbbrev();
1810 Die->setOffset(Offset);
1812 // Start the size with the size of abbreviation code.
1813 Offset += getULEB128Size(Die->getAbbrevNumber());
1815 const SmallVectorImpl<DIEValue *> &Values = Die->getValues();
1816 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
1818 // Size the DIE attribute values.
1819 for (unsigned i = 0, N = Values.size(); i < N; ++i)
1820 // Size attribute value.
1821 Offset += Values[i]->SizeOf(Asm, AbbrevData[i].getForm());
1823 // Get the children.
1824 const std::vector<DIE *> &Children = Die->getChildren();
1826 // Size the DIE children if any.
1827 if (!Children.empty()) {
1828 assert(Abbrev.hasChildren() && "Children flag not set");
1830 for (DIE *Child : Children)
1831 Offset = computeSizeAndOffset(Child, Offset);
1833 // End of children marker.
1834 Offset += sizeof(int8_t);
1837 Die->setSize(Offset - Die->getOffset());
1841 // Compute the size and offset for each DIE.
1842 void DwarfFile::computeSizeAndOffsets() {
1843 // Offset from the first CU in the debug info section is 0 initially.
1844 unsigned SecOffset = 0;
1846 // Iterate over each compile unit and set the size and offsets for each
1847 // DIE within each compile unit. All offsets are CU relative.
1848 for (DwarfUnit *TheU : CUs) {
1849 TheU->setDebugInfoOffset(SecOffset);
1851 // CU-relative offset is reset to 0 here.
1852 unsigned Offset = sizeof(int32_t) + // Length of Unit Info
1853 TheU->getHeaderSize(); // Unit-specific headers
1855 // EndOffset here is CU-relative, after laying out
1856 // all of the CU DIE.
1857 unsigned EndOffset = computeSizeAndOffset(TheU->getUnitDie(), Offset);
1858 SecOffset += EndOffset;
1862 // Emit initial Dwarf sections with a label at the start of each one.
1863 void DwarfDebug::emitSectionLabels() {
1864 const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering();
1866 // Dwarf sections base addresses.
1867 DwarfInfoSectionSym =
1868 emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info");
1869 if (useSplitDwarf())
1870 DwarfInfoDWOSectionSym =
1871 emitSectionSym(Asm, TLOF.getDwarfInfoDWOSection(), "section_info_dwo");
1872 DwarfAbbrevSectionSym =
1873 emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev");
1874 if (useSplitDwarf())
1875 DwarfAbbrevDWOSectionSym = emitSectionSym(
1876 Asm, TLOF.getDwarfAbbrevDWOSection(), "section_abbrev_dwo");
1877 if (GenerateARangeSection)
1878 emitSectionSym(Asm, TLOF.getDwarfARangesSection());
1880 DwarfLineSectionSym =
1881 emitSectionSym(Asm, TLOF.getDwarfLineSection(), "section_line");
1882 if (GenerateGnuPubSections) {
1883 DwarfGnuPubNamesSectionSym =
1884 emitSectionSym(Asm, TLOF.getDwarfGnuPubNamesSection());
1885 DwarfGnuPubTypesSectionSym =
1886 emitSectionSym(Asm, TLOF.getDwarfGnuPubTypesSection());
1887 } else if (HasDwarfPubSections) {
1888 emitSectionSym(Asm, TLOF.getDwarfPubNamesSection());
1889 emitSectionSym(Asm, TLOF.getDwarfPubTypesSection());
1892 DwarfStrSectionSym =
1893 emitSectionSym(Asm, TLOF.getDwarfStrSection(), "info_string");
1894 if (useSplitDwarf()) {
1895 DwarfStrDWOSectionSym =
1896 emitSectionSym(Asm, TLOF.getDwarfStrDWOSection(), "skel_string");
1897 DwarfAddrSectionSym =
1898 emitSectionSym(Asm, TLOF.getDwarfAddrSection(), "addr_sec");
1899 DwarfDebugLocSectionSym =
1900 emitSectionSym(Asm, TLOF.getDwarfLocDWOSection(), "skel_loc");
1902 DwarfDebugLocSectionSym =
1903 emitSectionSym(Asm, TLOF.getDwarfLocSection(), "section_debug_loc");
1904 DwarfDebugRangeSectionSym =
1905 emitSectionSym(Asm, TLOF.getDwarfRangesSection(), "debug_range");
1908 // Recursively emits a debug information entry.
1909 void DwarfDebug::emitDIE(DIE *Die) {
1910 // Get the abbreviation for this DIE.
1911 const DIEAbbrev &Abbrev = Die->getAbbrev();
1913 // Emit the code (index) for the abbreviation.
1914 if (Asm->isVerbose())
1915 Asm->OutStreamer.AddComment("Abbrev [" + Twine(Abbrev.getNumber()) +
1916 "] 0x" + Twine::utohexstr(Die->getOffset()) +
1917 ":0x" + Twine::utohexstr(Die->getSize()) + " " +
1918 dwarf::TagString(Abbrev.getTag()));
1919 Asm->EmitULEB128(Abbrev.getNumber());
1921 const SmallVectorImpl<DIEValue *> &Values = Die->getValues();
1922 const SmallVectorImpl<DIEAbbrevData> &AbbrevData = Abbrev.getData();
1924 // Emit the DIE attribute values.
1925 for (unsigned i = 0, N = Values.size(); i < N; ++i) {
1926 dwarf::Attribute Attr = AbbrevData[i].getAttribute();
1927 dwarf::Form Form = AbbrevData[i].getForm();
1928 assert(Form && "Too many attributes for DIE (check abbreviation)");
1930 if (Asm->isVerbose()) {
1931 Asm->OutStreamer.AddComment(dwarf::AttributeString(Attr));
1932 if (Attr == dwarf::DW_AT_accessibility)
1933 Asm->OutStreamer.AddComment(dwarf::AccessibilityString(
1934 cast<DIEInteger>(Values[i])->getValue()));
1937 // Emit an attribute using the defined form.
1938 Values[i]->EmitValue(Asm, Form);
1941 // Emit the DIE children if any.
1942 if (Abbrev.hasChildren()) {
1943 const std::vector<DIE *> &Children = Die->getChildren();
1945 for (DIE *Child : Children)
1948 Asm->OutStreamer.AddComment("End Of Children Mark");
1953 // Emit the various dwarf units to the unit section USection with
1954 // the abbreviations going into ASection.
1955 void DwarfFile::emitUnits(DwarfDebug *DD, const MCSymbol *ASectionSym) {
1956 for (DwarfUnit *TheU : CUs) {
1957 DIE *Die = TheU->getUnitDie();
1958 const MCSection *USection = TheU->getSection();
1959 Asm->OutStreamer.SwitchSection(USection);
1961 // Emit the compile units header.
1962 Asm->OutStreamer.EmitLabel(TheU->getLabelBegin());
1964 // Emit size of content not including length itself
1965 Asm->OutStreamer.AddComment("Length of Unit");
1966 Asm->EmitInt32(TheU->getHeaderSize() + Die->getSize());
1968 TheU->emitHeader(ASectionSym);
1971 Asm->OutStreamer.EmitLabel(TheU->getLabelEnd());
1975 // Emit the debug info section.
1976 void DwarfDebug::emitDebugInfo() {
1977 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1979 Holder.emitUnits(this, DwarfAbbrevSectionSym);
1982 // Emit the abbreviation section.
1983 void DwarfDebug::emitAbbreviations() {
1984 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
1986 Holder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevSection());
1989 void DwarfFile::emitAbbrevs(const MCSection *Section) {
1990 // Check to see if it is worth the effort.
1991 if (!Abbreviations.empty()) {
1992 // Start the debug abbrev section.
1993 Asm->OutStreamer.SwitchSection(Section);
1995 // For each abbrevation.
1996 for (const DIEAbbrev *Abbrev : Abbreviations) {
1997 // Emit the abbrevations code (base 1 index.)
1998 Asm->EmitULEB128(Abbrev->getNumber(), "Abbreviation Code");
2000 // Emit the abbreviations data.
2004 // Mark end of abbreviations.
2005 Asm->EmitULEB128(0, "EOM(3)");
2009 // Emit the last address of the section and the end of the line matrix.
2010 void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) {
2011 // Define last address of section.
2012 Asm->OutStreamer.AddComment("Extended Op");
2015 Asm->OutStreamer.AddComment("Op size");
2016 Asm->EmitInt8(Asm->getDataLayout().getPointerSize() + 1);
2017 Asm->OutStreamer.AddComment("DW_LNE_set_address");
2018 Asm->EmitInt8(dwarf::DW_LNE_set_address);
2020 Asm->OutStreamer.AddComment("Section end label");
2022 Asm->OutStreamer.EmitSymbolValue(
2023 Asm->GetTempSymbol("section_end", SectionEnd),
2024 Asm->getDataLayout().getPointerSize());
2026 // Mark end of matrix.
2027 Asm->OutStreamer.AddComment("DW_LNE_end_sequence");
2033 // Emit visible names into a hashed accelerator table section.
2034 void DwarfDebug::emitAccelNames() {
2036 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, dwarf::DW_FORM_data4));
2037 for (DwarfUnit *TheU : getUnits()) {
2038 for (const auto &GI : TheU->getAccelNames()) {
2039 StringRef Name = GI.getKey();
2040 for (const DIE *D : GI.second)
2041 AT.AddName(Name, D);
2045 AT.FinalizeTable(Asm, "Names");
2046 Asm->OutStreamer.SwitchSection(
2047 Asm->getObjFileLowering().getDwarfAccelNamesSection());
2048 MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin");
2049 Asm->OutStreamer.EmitLabel(SectionBegin);
2051 // Emit the full data.
2052 AT.Emit(Asm, SectionBegin, &InfoHolder);
2055 // Emit objective C classes and categories into a hashed accelerator table
2057 void DwarfDebug::emitAccelObjC() {
2059 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, dwarf::DW_FORM_data4));
2060 for (DwarfUnit *TheU : getUnits()) {
2061 for (const auto &GI : TheU->getAccelObjC()) {
2062 StringRef Name = GI.getKey();
2063 for (const DIE *D : GI.second)
2064 AT.AddName(Name, D);
2068 AT.FinalizeTable(Asm, "ObjC");
2069 Asm->OutStreamer.SwitchSection(
2070 Asm->getObjFileLowering().getDwarfAccelObjCSection());
2071 MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin");
2072 Asm->OutStreamer.EmitLabel(SectionBegin);
2074 // Emit the full data.
2075 AT.Emit(Asm, SectionBegin, &InfoHolder);
2078 // Emit namespace dies into a hashed accelerator table.
2079 void DwarfDebug::emitAccelNamespaces() {
2081 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, dwarf::DW_FORM_data4));
2082 for (DwarfUnit *TheU : getUnits()) {
2083 for (const auto &GI : TheU->getAccelNamespace()) {
2084 StringRef Name = GI.getKey();
2085 for (const DIE *D : GI.second)
2086 AT.AddName(Name, D);
2090 AT.FinalizeTable(Asm, "namespac");
2091 Asm->OutStreamer.SwitchSection(
2092 Asm->getObjFileLowering().getDwarfAccelNamespaceSection());
2093 MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin");
2094 Asm->OutStreamer.EmitLabel(SectionBegin);
2096 // Emit the full data.
2097 AT.Emit(Asm, SectionBegin, &InfoHolder);
2100 // Emit type dies into a hashed accelerator table.
2101 void DwarfDebug::emitAccelTypes() {
2102 std::vector<DwarfAccelTable::Atom> Atoms;
2104 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_offset, dwarf::DW_FORM_data4));
2106 DwarfAccelTable::Atom(dwarf::DW_ATOM_die_tag, dwarf::DW_FORM_data2));
2108 DwarfAccelTable::Atom(dwarf::DW_ATOM_type_flags, dwarf::DW_FORM_data1));
2109 DwarfAccelTable AT(Atoms);
2110 for (DwarfUnit *TheU : getUnits()) {
2111 for (const auto &GI : TheU->getAccelTypes()) {
2112 StringRef Name = GI.getKey();
2113 for (const auto &DI : GI.second)
2114 AT.AddName(Name, DI.first, DI.second);
2118 AT.FinalizeTable(Asm, "types");
2119 Asm->OutStreamer.SwitchSection(
2120 Asm->getObjFileLowering().getDwarfAccelTypesSection());
2121 MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin");
2122 Asm->OutStreamer.EmitLabel(SectionBegin);
2124 // Emit the full data.
2125 AT.Emit(Asm, SectionBegin, &InfoHolder);
2128 // Public name handling.
2129 // The format for the various pubnames:
2131 // dwarf pubnames - offset/name pairs where the offset is the offset into the CU
2132 // for the DIE that is named.
2134 // gnu pubnames - offset/index value/name tuples where the offset is the offset
2135 // into the CU and the index value is computed according to the type of value
2136 // for the DIE that is named.
2138 // For type units the offset is the offset of the skeleton DIE. For split dwarf
2139 // it's the offset within the debug_info/debug_types dwo section, however, the
2140 // reference in the pubname header doesn't change.
2142 /// computeIndexValue - Compute the gdb index value for the DIE and CU.
2143 static dwarf::PubIndexEntryDescriptor computeIndexValue(DwarfUnit *CU,
2145 dwarf::GDBIndexEntryLinkage Linkage = dwarf::GIEL_STATIC;
2147 // We could have a specification DIE that has our most of our knowledge,
2148 // look for that now.
2149 DIEValue *SpecVal = Die->findAttribute(dwarf::DW_AT_specification);
2151 DIE *SpecDIE = cast<DIEEntry>(SpecVal)->getEntry();
2152 if (SpecDIE->findAttribute(dwarf::DW_AT_external))
2153 Linkage = dwarf::GIEL_EXTERNAL;
2154 } else if (Die->findAttribute(dwarf::DW_AT_external))
2155 Linkage = dwarf::GIEL_EXTERNAL;
2157 switch (Die->getTag()) {
2158 case dwarf::DW_TAG_class_type:
2159 case dwarf::DW_TAG_structure_type:
2160 case dwarf::DW_TAG_union_type:
2161 case dwarf::DW_TAG_enumeration_type:
2162 return dwarf::PubIndexEntryDescriptor(
2163 dwarf::GIEK_TYPE, CU->getLanguage() != dwarf::DW_LANG_C_plus_plus
2164 ? dwarf::GIEL_STATIC
2165 : dwarf::GIEL_EXTERNAL);
2166 case dwarf::DW_TAG_typedef:
2167 case dwarf::DW_TAG_base_type:
2168 case dwarf::DW_TAG_subrange_type:
2169 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_TYPE, dwarf::GIEL_STATIC);
2170 case dwarf::DW_TAG_namespace:
2171 return dwarf::GIEK_TYPE;
2172 case dwarf::DW_TAG_subprogram:
2173 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_FUNCTION, Linkage);
2174 case dwarf::DW_TAG_constant:
2175 case dwarf::DW_TAG_variable:
2176 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE, Linkage);
2177 case dwarf::DW_TAG_enumerator:
2178 return dwarf::PubIndexEntryDescriptor(dwarf::GIEK_VARIABLE,
2179 dwarf::GIEL_STATIC);
2181 return dwarf::GIEK_NONE;
2185 /// emitDebugPubNames - Emit visible names into a debug pubnames section.
2187 void DwarfDebug::emitDebugPubNames(bool GnuStyle) {
2188 const MCSection *PSec =
2189 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubNamesSection()
2190 : Asm->getObjFileLowering().getDwarfPubNamesSection();
2192 emitDebugPubSection(GnuStyle, PSec, "Names", &DwarfUnit::getGlobalNames);
2195 void DwarfDebug::emitDebugPubSection(
2196 bool GnuStyle, const MCSection *PSec, StringRef Name,
2197 const StringMap<const DIE *> &(DwarfUnit::*Accessor)() const) {
2198 for (const auto &NU : CUMap) {
2199 DwarfCompileUnit *TheU = NU.second;
2201 const auto &Globals = (TheU->*Accessor)();
2203 if (Globals.empty())
2206 if (auto Skeleton = static_cast<DwarfCompileUnit *>(TheU->getSkeleton()))
2208 unsigned ID = TheU->getUniqueID();
2210 // Start the dwarf pubnames section.
2211 Asm->OutStreamer.SwitchSection(PSec);
2214 Asm->OutStreamer.AddComment("Length of Public " + Name + " Info");
2215 MCSymbol *BeginLabel = Asm->GetTempSymbol("pub" + Name + "_begin", ID);
2216 MCSymbol *EndLabel = Asm->GetTempSymbol("pub" + Name + "_end", ID);
2217 Asm->EmitLabelDifference(EndLabel, BeginLabel, 4);
2219 Asm->OutStreamer.EmitLabel(BeginLabel);
2221 Asm->OutStreamer.AddComment("DWARF Version");
2222 Asm->EmitInt16(dwarf::DW_PUBNAMES_VERSION);
2224 Asm->OutStreamer.AddComment("Offset of Compilation Unit Info");
2225 Asm->EmitSectionOffset(TheU->getLabelBegin(), TheU->getSectionSym());
2227 Asm->OutStreamer.AddComment("Compilation Unit Length");
2228 Asm->EmitLabelDifference(TheU->getLabelEnd(), TheU->getLabelBegin(), 4);
2230 // Emit the pubnames for this compilation unit.
2231 for (const auto &GI : Globals) {
2232 const char *Name = GI.getKeyData();
2233 const DIE *Entity = GI.second;
2235 Asm->OutStreamer.AddComment("DIE offset");
2236 Asm->EmitInt32(Entity->getOffset());
2239 dwarf::PubIndexEntryDescriptor Desc = computeIndexValue(TheU, Entity);
2240 Asm->OutStreamer.AddComment(
2241 Twine("Kind: ") + dwarf::GDBIndexEntryKindString(Desc.Kind) + ", " +
2242 dwarf::GDBIndexEntryLinkageString(Desc.Linkage));
2243 Asm->EmitInt8(Desc.toBits());
2246 Asm->OutStreamer.AddComment("External Name");
2247 Asm->OutStreamer.EmitBytes(StringRef(Name, GI.getKeyLength() + 1));
2250 Asm->OutStreamer.AddComment("End Mark");
2252 Asm->OutStreamer.EmitLabel(EndLabel);
2256 void DwarfDebug::emitDebugPubTypes(bool GnuStyle) {
2257 const MCSection *PSec =
2258 GnuStyle ? Asm->getObjFileLowering().getDwarfGnuPubTypesSection()
2259 : Asm->getObjFileLowering().getDwarfPubTypesSection();
2261 emitDebugPubSection(GnuStyle, PSec, "Types", &DwarfUnit::getGlobalTypes);
2264 // Emit strings into a string section.
2265 void DwarfFile::emitStrings(const MCSection *StrSection,
2266 const MCSection *OffsetSection = NULL,
2267 const MCSymbol *StrSecSym = NULL) {
2269 if (StringPool.empty())
2272 // Start the dwarf str section.
2273 Asm->OutStreamer.SwitchSection(StrSection);
2275 // Get all of the string pool entries and put them in an array by their ID so
2276 // we can sort them.
2277 SmallVector<std::pair<unsigned, const StrPool::value_type *>, 64 > Entries;
2279 for (const auto &I : StringPool)
2280 Entries.push_back(std::make_pair(I.second.second, &I));
2282 array_pod_sort(Entries.begin(), Entries.end());
2284 for (const auto &Entry : Entries) {
2285 // Emit a label for reference from debug information entries.
2286 Asm->OutStreamer.EmitLabel(Entry.second->getValue().first);
2288 // Emit the string itself with a terminating null byte.
2289 Asm->OutStreamer.EmitBytes(StringRef(Entry.second->getKeyData(),
2290 Entry.second->getKeyLength() + 1));
2293 // If we've got an offset section go ahead and emit that now as well.
2294 if (OffsetSection) {
2295 Asm->OutStreamer.SwitchSection(OffsetSection);
2296 unsigned offset = 0;
2297 unsigned size = 4; // FIXME: DWARF64 is 8.
2298 for (const auto &Entry : Entries) {
2299 Asm->OutStreamer.EmitIntValue(offset, size);
2300 offset += Entry.second->getKeyLength() + 1;
2305 // Emit addresses into the section given.
2306 void DwarfFile::emitAddresses(const MCSection *AddrSection) {
2308 if (AddressPool.empty())
2311 // Start the dwarf addr section.
2312 Asm->OutStreamer.SwitchSection(AddrSection);
2314 // Order the address pool entries by ID
2315 SmallVector<const MCExpr *, 64> Entries(AddressPool.size());
2317 for (const auto &I : AddressPool)
2318 Entries[I.second.Number] =
2320 ? Asm->getObjFileLowering().getDebugThreadLocalSymbol(I.first)
2321 : MCSymbolRefExpr::Create(I.first, Asm->OutContext);
2323 for (const MCExpr *Entry : Entries)
2324 Asm->OutStreamer.EmitValue(Entry, Asm->getDataLayout().getPointerSize());
2327 // Emit visible names into a debug str section.
2328 void DwarfDebug::emitDebugStr() {
2329 DwarfFile &Holder = useSplitDwarf() ? SkeletonHolder : InfoHolder;
2330 Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection());
2333 void DwarfDebug::emitDebugLocEntry(ByteStreamer &Streamer,
2334 const DebugLocEntry &Entry) {
2335 DIVariable DV(Entry.getVariable());
2336 if (Entry.isInt()) {
2337 DIBasicType BTy(resolve(DV.getType()));
2338 if (BTy.Verify() && (BTy.getEncoding() == dwarf::DW_ATE_signed ||
2339 BTy.getEncoding() == dwarf::DW_ATE_signed_char)) {
2340 Streamer.EmitInt8(dwarf::DW_OP_consts, "DW_OP_consts");
2341 Streamer.EmitSLEB128(Entry.getInt());
2343 Streamer.EmitInt8(dwarf::DW_OP_constu, "DW_OP_constu");
2344 Streamer.EmitULEB128(Entry.getInt());
2346 } else if (Entry.isLocation()) {
2347 MachineLocation Loc = Entry.getLoc();
2348 if (!DV.hasComplexAddress())
2350 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2352 // Complex address entry.
2353 unsigned N = DV.getNumAddrElements();
2355 if (N >= 2 && DV.getAddrElement(0) == DIBuilder::OpPlus) {
2356 if (Loc.getOffset()) {
2358 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2359 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
2360 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
2361 Streamer.EmitSLEB128(DV.getAddrElement(1));
2363 // If first address element is OpPlus then emit
2364 // DW_OP_breg + Offset instead of DW_OP_reg + Offset.
2365 MachineLocation TLoc(Loc.getReg(), DV.getAddrElement(1));
2366 Asm->EmitDwarfRegOp(Streamer, TLoc, DV.isIndirect());
2370 Asm->EmitDwarfRegOp(Streamer, Loc, DV.isIndirect());
2373 // Emit remaining complex address elements.
2374 for (; i < N; ++i) {
2375 uint64_t Element = DV.getAddrElement(i);
2376 if (Element == DIBuilder::OpPlus) {
2377 Streamer.EmitInt8(dwarf::DW_OP_plus_uconst, "DW_OP_plus_uconst");
2378 Streamer.EmitULEB128(DV.getAddrElement(++i));
2379 } else if (Element == DIBuilder::OpDeref) {
2381 Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
2383 llvm_unreachable("unknown Opcode found in complex address");
2387 // else ... ignore constant fp. There is not any good way to
2388 // to represent them here in dwarf.
2392 void DwarfDebug::emitDebugLocEntryLocation(const DebugLocEntry &Entry) {
2393 Asm->OutStreamer.AddComment("Loc expr size");
2394 MCSymbol *begin = Asm->OutStreamer.getContext().CreateTempSymbol();
2395 MCSymbol *end = Asm->OutStreamer.getContext().CreateTempSymbol();
2396 Asm->EmitLabelDifference(end, begin, 2);
2397 Asm->OutStreamer.EmitLabel(begin);
2399 APByteStreamer Streamer(*Asm);
2400 emitDebugLocEntry(Streamer, Entry);
2402 Asm->OutStreamer.EmitLabel(end);
2405 // Emit locations into the debug loc section.
2406 void DwarfDebug::emitDebugLoc() {
2407 // Start the dwarf loc section.
2408 Asm->OutStreamer.SwitchSection(
2409 Asm->getObjFileLowering().getDwarfLocSection());
2410 unsigned char Size = Asm->getDataLayout().getPointerSize();
2411 for (const auto &DebugLoc : DotDebugLocEntries) {
2412 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2413 for (const auto &Entry : DebugLoc.List) {
2414 // Set up the range. This range is relative to the entry point of the
2415 // compile unit. This is a hard coded 0 for low_pc when we're emitting
2416 // ranges, or the DW_AT_low_pc on the compile unit otherwise.
2417 const DwarfCompileUnit *CU = Entry.getCU();
2418 if (CU->getRanges().size() == 1) {
2419 // Grab the begin symbol from the first range as our base.
2420 const MCSymbol *Base = CU->getRanges()[0].getStart();
2421 Asm->EmitLabelDifference(Entry.getBeginSym(), Base, Size);
2422 Asm->EmitLabelDifference(Entry.getEndSym(), Base, Size);
2424 Asm->OutStreamer.EmitSymbolValue(Entry.getBeginSym(), Size);
2425 Asm->OutStreamer.EmitSymbolValue(Entry.getEndSym(), Size);
2428 emitDebugLocEntryLocation(Entry);
2430 Asm->OutStreamer.EmitIntValue(0, Size);
2431 Asm->OutStreamer.EmitIntValue(0, Size);
2435 void DwarfDebug::emitDebugLocDWO() {
2436 Asm->OutStreamer.SwitchSection(
2437 Asm->getObjFileLowering().getDwarfLocDWOSection());
2438 for (const auto &DebugLoc : DotDebugLocEntries) {
2439 Asm->OutStreamer.EmitLabel(DebugLoc.Label);
2440 for (const auto &Entry : DebugLoc.List) {
2441 // Just always use start_length for now - at least that's one address
2442 // rather than two. We could get fancier and try to, say, reuse an
2443 // address we know we've emitted elsewhere (the start of the function?
2444 // The start of the CU or CU subrange that encloses this range?)
2445 Asm->EmitInt8(dwarf::DW_LLE_start_length_entry);
2446 unsigned idx = InfoHolder.getAddrPoolIndex(Entry.getBeginSym());
2447 Asm->EmitULEB128(idx);
2448 Asm->EmitLabelDifference(Entry.getEndSym(), Entry.getBeginSym(), 4);
2450 emitDebugLocEntryLocation(Entry);
2452 Asm->EmitInt8(dwarf::DW_LLE_end_of_list_entry);
2457 const MCSymbol *Start, *End;
2460 // Emit a debug aranges section, containing a CU lookup for any
2461 // address we can tie back to a CU.
2462 void DwarfDebug::emitDebugARanges() {
2463 // Start the dwarf aranges section.
2464 Asm->OutStreamer.SwitchSection(
2465 Asm->getObjFileLowering().getDwarfARangesSection());
2467 typedef DenseMap<DwarfCompileUnit *, std::vector<ArangeSpan> > SpansType;
2471 // Build a list of sections used.
2472 std::vector<const MCSection *> Sections;
2473 for (const auto &it : SectionMap) {
2474 const MCSection *Section = it.first;
2475 Sections.push_back(Section);
2478 // Sort the sections into order.
2479 // This is only done to ensure consistent output order across different runs.
2480 std::sort(Sections.begin(), Sections.end(), SectionSort);
2482 // Build a set of address spans, sorted by CU.
2483 for (const MCSection *Section : Sections) {
2484 SmallVector<SymbolCU, 8> &List = SectionMap[Section];
2485 if (List.size() < 2)
2488 // Sort the symbols by offset within the section.
2489 std::sort(List.begin(), List.end(),
2490 [&](const SymbolCU &A, const SymbolCU &B) {
2491 unsigned IA = A.Sym ? Asm->OutStreamer.GetSymbolOrder(A.Sym) : 0;
2492 unsigned IB = B.Sym ? Asm->OutStreamer.GetSymbolOrder(B.Sym) : 0;
2494 // Symbols with no order assigned should be placed at the end.
2495 // (e.g. section end labels)
2503 // If we have no section (e.g. common), just write out
2504 // individual spans for each symbol.
2505 if (Section == NULL) {
2506 for (const SymbolCU &Cur : List) {
2508 Span.Start = Cur.Sym;
2511 Spans[Cur.CU].push_back(Span);
2514 // Build spans between each label.
2515 const MCSymbol *StartSym = List[0].Sym;
2516 for (size_t n = 1, e = List.size(); n < e; n++) {
2517 const SymbolCU &Prev = List[n - 1];
2518 const SymbolCU &Cur = List[n];
2520 // Try and build the longest span we can within the same CU.
2521 if (Cur.CU != Prev.CU) {
2523 Span.Start = StartSym;
2525 Spans[Prev.CU].push_back(Span);
2532 unsigned PtrSize = Asm->getDataLayout().getPointerSize();
2534 // Build a list of CUs used.
2535 std::vector<DwarfCompileUnit *> CUs;
2536 for (const auto &it : Spans) {
2537 DwarfCompileUnit *CU = it.first;
2541 // Sort the CU list (again, to ensure consistent output order).
2542 std::sort(CUs.begin(), CUs.end(), [](const DwarfUnit *A, const DwarfUnit *B) {
2543 return A->getUniqueID() < B->getUniqueID();
2546 // Emit an arange table for each CU we used.
2547 for (DwarfCompileUnit *CU : CUs) {
2548 std::vector<ArangeSpan> &List = Spans[CU];
2550 // Emit size of content not including length itself.
2551 unsigned ContentSize =
2552 sizeof(int16_t) + // DWARF ARange version number
2553 sizeof(int32_t) + // Offset of CU in the .debug_info section
2554 sizeof(int8_t) + // Pointer Size (in bytes)
2555 sizeof(int8_t); // Segment Size (in bytes)
2557 unsigned TupleSize = PtrSize * 2;
2559 // 7.20 in the Dwarf specs requires the table to be aligned to a tuple.
2561 OffsetToAlignment(sizeof(int32_t) + ContentSize, TupleSize);
2563 ContentSize += Padding;
2564 ContentSize += (List.size() + 1) * TupleSize;
2566 // For each compile unit, write the list of spans it covers.
2567 Asm->OutStreamer.AddComment("Length of ARange Set");
2568 Asm->EmitInt32(ContentSize);
2569 Asm->OutStreamer.AddComment("DWARF Arange version number");
2570 Asm->EmitInt16(dwarf::DW_ARANGES_VERSION);
2571 Asm->OutStreamer.AddComment("Offset Into Debug Info Section");
2572 Asm->EmitSectionOffset(CU->getLocalLabelBegin(), CU->getLocalSectionSym());
2573 Asm->OutStreamer.AddComment("Address Size (in bytes)");
2574 Asm->EmitInt8(PtrSize);
2575 Asm->OutStreamer.AddComment("Segment Size (in bytes)");
2578 Asm->OutStreamer.EmitFill(Padding, 0xff);
2580 for (const ArangeSpan &Span : List) {
2581 Asm->EmitLabelReference(Span.Start, PtrSize);
2583 // Calculate the size as being from the span start to it's end.
2585 Asm->EmitLabelDifference(Span.End, Span.Start, PtrSize);
2587 // For symbols without an end marker (e.g. common), we
2588 // write a single arange entry containing just that one symbol.
2589 uint64_t Size = SymSize[Span.Start];
2593 Asm->OutStreamer.EmitIntValue(Size, PtrSize);
2597 Asm->OutStreamer.AddComment("ARange terminator");
2598 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2599 Asm->OutStreamer.EmitIntValue(0, PtrSize);
2603 // Emit visible names into a debug ranges section.
2604 void DwarfDebug::emitDebugRanges() {
2605 // Start the dwarf ranges section.
2606 Asm->OutStreamer.SwitchSection(
2607 Asm->getObjFileLowering().getDwarfRangesSection());
2609 // Size for our labels.
2610 unsigned char Size = Asm->getDataLayout().getPointerSize();
2612 // Grab the specific ranges for the compile units in the module.
2613 for (const auto &I : CUMap) {
2614 DwarfCompileUnit *TheCU = I.second;
2616 // Emit a symbol so we can find the beginning of our ranges.
2617 Asm->OutStreamer.EmitLabel(TheCU->getLabelRange());
2619 // Iterate over the misc ranges for the compile units in the module.
2620 for (const RangeSpanList &List : TheCU->getRangeLists()) {
2621 // Emit our symbol so we can find the beginning of the range.
2622 Asm->OutStreamer.EmitLabel(List.getSym());
2624 for (const RangeSpan &Range : List.getRanges()) {
2625 const MCSymbol *Begin = Range.getStart();
2626 const MCSymbol *End = Range.getEnd();
2627 assert(Begin && "Range without a begin symbol?");
2628 assert(End && "Range without an end symbol?");
2629 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2630 Asm->OutStreamer.EmitSymbolValue(End, Size);
2633 // And terminate the list with two 0 values.
2634 Asm->OutStreamer.EmitIntValue(0, Size);
2635 Asm->OutStreamer.EmitIntValue(0, Size);
2638 // Now emit a range for the CU itself.
2639 if (TheCU->getRanges().size() > 1) {
2640 Asm->OutStreamer.EmitLabel(
2641 Asm->GetTempSymbol("cu_ranges", TheCU->getUniqueID()));
2642 for (const RangeSpan &Range : TheCU->getRanges()) {
2643 const MCSymbol *Begin = Range.getStart();
2644 const MCSymbol *End = Range.getEnd();
2645 assert(Begin && "Range without a begin symbol?");
2646 assert(End && "Range without an end symbol?");
2647 Asm->OutStreamer.EmitSymbolValue(Begin, Size);
2648 Asm->OutStreamer.EmitSymbolValue(End, Size);
2650 // And terminate the list with two 0 values.
2651 Asm->OutStreamer.EmitIntValue(0, Size);
2652 Asm->OutStreamer.EmitIntValue(0, Size);
2657 // DWARF5 Experimental Separate Dwarf emitters.
2659 void DwarfDebug::initSkeletonUnit(const DwarfUnit *U, DIE *Die,
2661 NewU->addLocalString(Die, dwarf::DW_AT_GNU_dwo_name,
2662 U->getCUNode().getSplitDebugFilename());
2664 if (!CompilationDir.empty())
2665 NewU->addLocalString(Die, dwarf::DW_AT_comp_dir, CompilationDir);
2667 addGnuPubAttributes(NewU, Die);
2669 SkeletonHolder.addUnit(NewU);
2672 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_stmt_list,
2673 // DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_dwo_name, DW_AT_dwo_id,
2674 // DW_AT_addr_base, DW_AT_ranges_base.
2675 DwarfCompileUnit *DwarfDebug::constructSkeletonCU(const DwarfCompileUnit *CU) {
2677 DIE *Die = new DIE(dwarf::DW_TAG_compile_unit);
2678 DwarfCompileUnit *NewCU = new DwarfCompileUnit(
2679 CU->getUniqueID(), Die, CU->getCUNode(), Asm, this, &SkeletonHolder);
2680 NewCU->initSection(Asm->getObjFileLowering().getDwarfInfoSection(),
2681 DwarfInfoSectionSym);
2683 NewCU->initStmtList(DwarfLineSectionSym);
2685 initSkeletonUnit(CU, Die, NewCU);
2690 // This DIE has the following attributes: DW_AT_comp_dir, DW_AT_dwo_name,
2692 DwarfTypeUnit *DwarfDebug::constructSkeletonTU(DwarfTypeUnit *TU) {
2693 DwarfCompileUnit &CU = static_cast<DwarfCompileUnit &>(
2694 *SkeletonHolder.getUnits()[TU->getCU().getUniqueID()]);
2696 DIE *Die = new DIE(dwarf::DW_TAG_type_unit);
2697 DwarfTypeUnit *NewTU =
2698 new DwarfTypeUnit(TU->getUniqueID(), Die, CU, Asm, this, &SkeletonHolder);
2699 NewTU->setTypeSignature(TU->getTypeSignature());
2700 NewTU->setType(NULL);
2702 Asm->getObjFileLowering().getDwarfTypesSection(TU->getTypeSignature()));
2704 initSkeletonUnit(TU, Die, NewTU);
2708 // Emit the .debug_info.dwo section for separated dwarf. This contains the
2709 // compile units that would normally be in debug_info.
2710 void DwarfDebug::emitDebugInfoDWO() {
2711 assert(useSplitDwarf() && "No split dwarf debug info?");
2712 // Don't pass an abbrev symbol, using a constant zero instead so as not to
2713 // emit relocations into the dwo file.
2714 InfoHolder.emitUnits(this, /* AbbrevSymbol */nullptr);
2717 // Emit the .debug_abbrev.dwo section for separated dwarf. This contains the
2718 // abbreviations for the .debug_info.dwo section.
2719 void DwarfDebug::emitDebugAbbrevDWO() {
2720 assert(useSplitDwarf() && "No split dwarf?");
2721 InfoHolder.emitAbbrevs(Asm->getObjFileLowering().getDwarfAbbrevDWOSection());
2724 void DwarfDebug::emitDebugLineDWO() {
2725 assert(useSplitDwarf() && "No split dwarf?");
2726 Asm->OutStreamer.SwitchSection(
2727 Asm->getObjFileLowering().getDwarfLineDWOSection());
2728 SplitTypeUnitFileTable.Emit(Asm->OutStreamer);
2731 // Emit the .debug_str.dwo section for separated dwarf. This contains the
2732 // string section and is identical in format to traditional .debug_str
2734 void DwarfDebug::emitDebugStrDWO() {
2735 assert(useSplitDwarf() && "No split dwarf?");
2736 const MCSection *OffSec =
2737 Asm->getObjFileLowering().getDwarfStrOffDWOSection();
2738 const MCSymbol *StrSym = DwarfStrSectionSym;
2739 InfoHolder.emitStrings(Asm->getObjFileLowering().getDwarfStrDWOSection(),
2743 MCDwarfDwoLineTable *DwarfDebug::getDwoLineTable(const DwarfCompileUnit &CU) {
2744 if (!useSplitDwarf())
2747 SplitTypeUnitFileTable.setCompilationDir(CU.getCUNode().getDirectory());
2748 return &SplitTypeUnitFileTable;
2751 void DwarfDebug::addDwarfTypeUnitType(DwarfCompileUnit &CU,
2752 StringRef Identifier, DIE *RefDie,
2753 DICompositeType CTy) {
2754 // Flag the type unit reference as a declaration so that if it contains
2755 // members (implicit special members, static data member definitions, member
2756 // declarations for definitions in this CU, etc) consumers don't get confused
2757 // and think this is a full definition.
2758 CU.addFlag(RefDie, dwarf::DW_AT_declaration);
2760 const DwarfTypeUnit *&TU = DwarfTypeUnits[CTy];
2762 CU.addDIETypeSignature(RefDie, *TU);
2766 DIE *UnitDie = new DIE(dwarf::DW_TAG_type_unit);
2767 DwarfTypeUnit *NewTU =
2768 new DwarfTypeUnit(InfoHolder.getUnits().size(), UnitDie, CU, Asm, this,
2769 &InfoHolder, getDwoLineTable(CU));
2771 InfoHolder.addUnit(NewTU);
2773 NewTU->addUInt(UnitDie, dwarf::DW_AT_language, dwarf::DW_FORM_data2,
2777 Hash.update(Identifier);
2778 // ... take the least significant 8 bytes and return those. Our MD5
2779 // implementation always returns its results in little endian, swap bytes
2781 MD5::MD5Result Result;
2783 uint64_t Signature = *reinterpret_cast<support::ulittle64_t *>(Result + 8);
2784 NewTU->setTypeSignature(Signature);
2785 if (useSplitDwarf())
2786 NewTU->setSkeleton(constructSkeletonTU(NewTU));
2788 CU.applyStmtList(*UnitDie);
2790 NewTU->setType(NewTU->createTypeDIE(CTy));
2794 ? Asm->getObjFileLowering().getDwarfTypesDWOSection(Signature)
2795 : Asm->getObjFileLowering().getDwarfTypesSection(Signature));
2797 CU.addDIETypeSignature(RefDie, *NewTU);
2800 void DwarfDebug::attachLowHighPC(DwarfCompileUnit *Unit, DIE *D,
2801 MCSymbol *Begin, MCSymbol *End) {
2802 Unit->addLabelAddress(D, dwarf::DW_AT_low_pc, Begin);
2803 if (DwarfVersion < 4)
2804 Unit->addLabelAddress(D, dwarf::DW_AT_high_pc, End);
2806 Unit->addLabelDelta(D, dwarf::DW_AT_high_pc, End, Begin);