1 //===- llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp ----------------------===//
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7 //===----------------------------------------------------------------------===//
9 // This file contains support for writing Microsoft CodeView debug info.
11 //===----------------------------------------------------------------------===//
13 #include "CodeViewDebug.h"
14 #include "DwarfExpression.h"
15 #include "llvm/ADT/APSInt.h"
16 #include "llvm/ADT/ArrayRef.h"
17 #include "llvm/ADT/DenseMap.h"
18 #include "llvm/ADT/DenseSet.h"
19 #include "llvm/ADT/MapVector.h"
20 #include "llvm/ADT/None.h"
21 #include "llvm/ADT/Optional.h"
22 #include "llvm/ADT/STLExtras.h"
23 #include "llvm/ADT/SmallString.h"
24 #include "llvm/ADT/SmallVector.h"
25 #include "llvm/ADT/StringRef.h"
26 #include "llvm/ADT/TinyPtrVector.h"
27 #include "llvm/ADT/Triple.h"
28 #include "llvm/ADT/Twine.h"
29 #include "llvm/BinaryFormat/COFF.h"
30 #include "llvm/BinaryFormat/Dwarf.h"
31 #include "llvm/CodeGen/AsmPrinter.h"
32 #include "llvm/CodeGen/LexicalScopes.h"
33 #include "llvm/CodeGen/MachineFrameInfo.h"
34 #include "llvm/CodeGen/MachineFunction.h"
35 #include "llvm/CodeGen/MachineInstr.h"
36 #include "llvm/CodeGen/MachineModuleInfo.h"
37 #include "llvm/CodeGen/MachineOperand.h"
38 #include "llvm/CodeGen/TargetFrameLowering.h"
39 #include "llvm/CodeGen/TargetRegisterInfo.h"
40 #include "llvm/CodeGen/TargetSubtargetInfo.h"
41 #include "llvm/Config/llvm-config.h"
42 #include "llvm/DebugInfo/CodeView/CVTypeVisitor.h"
43 #include "llvm/DebugInfo/CodeView/CodeView.h"
44 #include "llvm/DebugInfo/CodeView/CodeViewRecordIO.h"
45 #include "llvm/DebugInfo/CodeView/ContinuationRecordBuilder.h"
46 #include "llvm/DebugInfo/CodeView/DebugInlineeLinesSubsection.h"
47 #include "llvm/DebugInfo/CodeView/EnumTables.h"
48 #include "llvm/DebugInfo/CodeView/Line.h"
49 #include "llvm/DebugInfo/CodeView/SymbolRecord.h"
50 #include "llvm/DebugInfo/CodeView/TypeDumpVisitor.h"
51 #include "llvm/DebugInfo/CodeView/TypeIndex.h"
52 #include "llvm/DebugInfo/CodeView/TypeRecord.h"
53 #include "llvm/DebugInfo/CodeView/TypeTableCollection.h"
54 #include "llvm/DebugInfo/CodeView/TypeVisitorCallbackPipeline.h"
55 #include "llvm/IR/Constants.h"
56 #include "llvm/IR/DataLayout.h"
57 #include "llvm/IR/DebugInfoMetadata.h"
58 #include "llvm/IR/DebugLoc.h"
59 #include "llvm/IR/Function.h"
60 #include "llvm/IR/GlobalValue.h"
61 #include "llvm/IR/GlobalVariable.h"
62 #include "llvm/IR/Metadata.h"
63 #include "llvm/IR/Module.h"
64 #include "llvm/MC/MCAsmInfo.h"
65 #include "llvm/MC/MCContext.h"
66 #include "llvm/MC/MCSectionCOFF.h"
67 #include "llvm/MC/MCStreamer.h"
68 #include "llvm/MC/MCSymbol.h"
69 #include "llvm/Support/BinaryByteStream.h"
70 #include "llvm/Support/BinaryStreamReader.h"
71 #include "llvm/Support/BinaryStreamWriter.h"
72 #include "llvm/Support/Casting.h"
73 #include "llvm/Support/CommandLine.h"
74 #include "llvm/Support/Compiler.h"
75 #include "llvm/Support/Endian.h"
76 #include "llvm/Support/Error.h"
77 #include "llvm/Support/ErrorHandling.h"
78 #include "llvm/Support/FormatVariadic.h"
79 #include "llvm/Support/Path.h"
80 #include "llvm/Support/SMLoc.h"
81 #include "llvm/Support/ScopedPrinter.h"
82 #include "llvm/Target/TargetLoweringObjectFile.h"
83 #include "llvm/Target/TargetMachine.h"
96 using namespace llvm::codeview;
99 class CVMCAdapter : public CodeViewRecordStreamer {
101 CVMCAdapter(MCStreamer &OS, TypeCollection &TypeTable)
102 : OS(&OS), TypeTable(TypeTable) {}
104 void emitBytes(StringRef Data) override { OS->emitBytes(Data); }
106 void emitIntValue(uint64_t Value, unsigned Size) override {
107 OS->emitIntValueInHex(Value, Size);
110 void emitBinaryData(StringRef Data) override { OS->emitBinaryData(Data); }
112 void AddComment(const Twine &T) override { OS->AddComment(T); }
114 void AddRawComment(const Twine &T) override { OS->emitRawComment(T); }
116 bool isVerboseAsm() override { return OS->isVerboseAsm(); }
118 std::string getTypeName(TypeIndex TI) override {
119 std::string TypeName;
120 if (!TI.isNoneType()) {
122 TypeName = std::string(TypeIndex::simpleTypeName(TI));
124 TypeName = std::string(TypeTable.getTypeName(TI));
130 MCStreamer *OS = nullptr;
131 TypeCollection &TypeTable;
135 static CPUType mapArchToCVCPUType(Triple::ArchType Type) {
137 case Triple::ArchType::x86:
138 return CPUType::Pentium3;
139 case Triple::ArchType::x86_64:
141 case Triple::ArchType::thumb:
142 return CPUType::Thumb;
143 case Triple::ArchType::aarch64:
144 return CPUType::ARM64;
146 report_fatal_error("target architecture doesn't map to a CodeView CPUType");
150 CodeViewDebug::CodeViewDebug(AsmPrinter *AP)
151 : DebugHandlerBase(AP), OS(*Asm->OutStreamer), TypeTable(Allocator) {
152 // If module doesn't have named metadata anchors or COFF debug section
153 // is not available, skip any debug info related stuff.
154 if (!MMI->getModule()->getNamedMetadata("llvm.dbg.cu") ||
155 !AP->getObjFileLowering().getCOFFDebugSymbolsSection()) {
157 MMI->setDebugInfoAvailability(false);
160 // Tell MMI that we have debug info.
161 MMI->setDebugInfoAvailability(true);
164 mapArchToCVCPUType(Triple(MMI->getModule()->getTargetTriple()).getArch());
166 collectGlobalVariableInfo();
168 // Check if we should emit type record hashes.
169 ConstantInt *GH = mdconst::extract_or_null<ConstantInt>(
170 MMI->getModule()->getModuleFlag("CodeViewGHash"));
171 EmitDebugGlobalHashes = GH && !GH->isZero();
174 StringRef CodeViewDebug::getFullFilepath(const DIFile *File) {
175 std::string &Filepath = FileToFilepathMap[File];
176 if (!Filepath.empty())
179 StringRef Dir = File->getDirectory(), Filename = File->getFilename();
181 // If this is a Unix-style path, just use it as is. Don't try to canonicalize
182 // it textually because one of the path components could be a symlink.
183 if (Dir.startswith("/") || Filename.startswith("/")) {
184 if (llvm::sys::path::is_absolute(Filename, llvm::sys::path::Style::posix))
186 Filepath = std::string(Dir);
187 if (Dir.back() != '/')
189 Filepath += Filename;
193 // Clang emits directory and relative filename info into the IR, but CodeView
194 // operates on full paths. We could change Clang to emit full paths too, but
195 // that would increase the IR size and probably not needed for other users.
196 // For now, just concatenate and canonicalize the path here.
197 if (Filename.find(':') == 1)
198 Filepath = std::string(Filename);
200 Filepath = (Dir + "\\" + Filename).str();
202 // Canonicalize the path. We have to do it textually because we may no longer
203 // have access the file in the filesystem.
204 // First, replace all slashes with backslashes.
205 std::replace(Filepath.begin(), Filepath.end(), '/', '\\');
207 // Remove all "\.\" with "\".
209 while ((Cursor = Filepath.find("\\.\\", Cursor)) != std::string::npos)
210 Filepath.erase(Cursor, 2);
212 // Replace all "\XXX\..\" with "\". Don't try too hard though as the original
213 // path should be well-formatted, e.g. start with a drive letter, etc.
215 while ((Cursor = Filepath.find("\\..\\", Cursor)) != std::string::npos) {
216 // Something's wrong if the path starts with "\..\", abort.
220 size_t PrevSlash = Filepath.rfind('\\', Cursor - 1);
221 if (PrevSlash == std::string::npos)
222 // Something's wrong, abort.
225 Filepath.erase(PrevSlash, Cursor + 3 - PrevSlash);
226 // The next ".." might be following the one we've just erased.
230 // Remove all duplicate backslashes.
232 while ((Cursor = Filepath.find("\\\\", Cursor)) != std::string::npos)
233 Filepath.erase(Cursor, 1);
238 unsigned CodeViewDebug::maybeRecordFile(const DIFile *F) {
239 StringRef FullPath = getFullFilepath(F);
240 unsigned NextId = FileIdMap.size() + 1;
241 auto Insertion = FileIdMap.insert(std::make_pair(FullPath, NextId));
242 if (Insertion.second) {
243 // We have to compute the full filepath and emit a .cv_file directive.
244 ArrayRef<uint8_t> ChecksumAsBytes;
245 FileChecksumKind CSKind = FileChecksumKind::None;
246 if (F->getChecksum()) {
247 std::string Checksum = fromHex(F->getChecksum()->Value);
248 void *CKMem = OS.getContext().allocate(Checksum.size(), 1);
249 memcpy(CKMem, Checksum.data(), Checksum.size());
250 ChecksumAsBytes = ArrayRef<uint8_t>(
251 reinterpret_cast<const uint8_t *>(CKMem), Checksum.size());
252 switch (F->getChecksum()->Kind) {
253 case DIFile::CSK_MD5:
254 CSKind = FileChecksumKind::MD5;
256 case DIFile::CSK_SHA1:
257 CSKind = FileChecksumKind::SHA1;
259 case DIFile::CSK_SHA256:
260 CSKind = FileChecksumKind::SHA256;
264 bool Success = OS.EmitCVFileDirective(NextId, FullPath, ChecksumAsBytes,
265 static_cast<unsigned>(CSKind));
267 assert(Success && ".cv_file directive failed");
269 return Insertion.first->second;
272 CodeViewDebug::InlineSite &
273 CodeViewDebug::getInlineSite(const DILocation *InlinedAt,
274 const DISubprogram *Inlinee) {
275 auto SiteInsertion = CurFn->InlineSites.insert({InlinedAt, InlineSite()});
276 InlineSite *Site = &SiteInsertion.first->second;
277 if (SiteInsertion.second) {
278 unsigned ParentFuncId = CurFn->FuncId;
279 if (const DILocation *OuterIA = InlinedAt->getInlinedAt())
281 getInlineSite(OuterIA, InlinedAt->getScope()->getSubprogram())
284 Site->SiteFuncId = NextFuncId++;
285 OS.EmitCVInlineSiteIdDirective(
286 Site->SiteFuncId, ParentFuncId, maybeRecordFile(InlinedAt->getFile()),
287 InlinedAt->getLine(), InlinedAt->getColumn(), SMLoc());
288 Site->Inlinee = Inlinee;
289 InlinedSubprograms.insert(Inlinee);
290 getFuncIdForSubprogram(Inlinee);
295 static StringRef getPrettyScopeName(const DIScope *Scope) {
296 StringRef ScopeName = Scope->getName();
297 if (!ScopeName.empty())
300 switch (Scope->getTag()) {
301 case dwarf::DW_TAG_enumeration_type:
302 case dwarf::DW_TAG_class_type:
303 case dwarf::DW_TAG_structure_type:
304 case dwarf::DW_TAG_union_type:
305 return "<unnamed-tag>";
306 case dwarf::DW_TAG_namespace:
307 return "`anonymous namespace'";
313 const DISubprogram *CodeViewDebug::collectParentScopeNames(
314 const DIScope *Scope, SmallVectorImpl<StringRef> &QualifiedNameComponents) {
315 const DISubprogram *ClosestSubprogram = nullptr;
316 while (Scope != nullptr) {
317 if (ClosestSubprogram == nullptr)
318 ClosestSubprogram = dyn_cast<DISubprogram>(Scope);
320 // If a type appears in a scope chain, make sure it gets emitted. The
321 // frontend will be responsible for deciding if this should be a forward
322 // declaration or a complete type.
323 if (const auto *Ty = dyn_cast<DICompositeType>(Scope))
324 DeferredCompleteTypes.push_back(Ty);
326 StringRef ScopeName = getPrettyScopeName(Scope);
327 if (!ScopeName.empty())
328 QualifiedNameComponents.push_back(ScopeName);
329 Scope = Scope->getScope();
331 return ClosestSubprogram;
334 static std::string formatNestedName(ArrayRef<StringRef> QualifiedNameComponents,
335 StringRef TypeName) {
336 std::string FullyQualifiedName;
337 for (StringRef QualifiedNameComponent :
338 llvm::reverse(QualifiedNameComponents)) {
339 FullyQualifiedName.append(std::string(QualifiedNameComponent));
340 FullyQualifiedName.append("::");
342 FullyQualifiedName.append(std::string(TypeName));
343 return FullyQualifiedName;
346 struct CodeViewDebug::TypeLoweringScope {
347 TypeLoweringScope(CodeViewDebug &CVD) : CVD(CVD) { ++CVD.TypeEmissionLevel; }
348 ~TypeLoweringScope() {
349 // Don't decrement TypeEmissionLevel until after emitting deferred types, so
350 // inner TypeLoweringScopes don't attempt to emit deferred types.
351 if (CVD.TypeEmissionLevel == 1)
352 CVD.emitDeferredCompleteTypes();
353 --CVD.TypeEmissionLevel;
358 std::string CodeViewDebug::getFullyQualifiedName(const DIScope *Scope,
360 // Ensure types in the scope chain are emitted as soon as possible.
361 // This can create otherwise a situation where S_UDTs are emitted while
362 // looping in emitDebugInfoForUDTs.
363 TypeLoweringScope S(*this);
364 SmallVector<StringRef, 5> QualifiedNameComponents;
365 collectParentScopeNames(Scope, QualifiedNameComponents);
366 return formatNestedName(QualifiedNameComponents, Name);
369 std::string CodeViewDebug::getFullyQualifiedName(const DIScope *Ty) {
370 const DIScope *Scope = Ty->getScope();
371 return getFullyQualifiedName(Scope, getPrettyScopeName(Ty));
374 TypeIndex CodeViewDebug::getScopeIndex(const DIScope *Scope) {
375 // No scope means global scope and that uses the zero index.
376 if (!Scope || isa<DIFile>(Scope))
379 assert(!isa<DIType>(Scope) && "shouldn't make a namespace scope for a type");
381 // Check if we've already translated this scope.
382 auto I = TypeIndices.find({Scope, nullptr});
383 if (I != TypeIndices.end())
386 // Build the fully qualified name of the scope.
387 std::string ScopeName = getFullyQualifiedName(Scope);
388 StringIdRecord SID(TypeIndex(), ScopeName);
389 auto TI = TypeTable.writeLeafType(SID);
390 return recordTypeIndexForDINode(Scope, TI);
393 TypeIndex CodeViewDebug::getFuncIdForSubprogram(const DISubprogram *SP) {
396 // Check if we've already translated this subprogram.
397 auto I = TypeIndices.find({SP, nullptr});
398 if (I != TypeIndices.end())
401 // The display name includes function template arguments. Drop them to match
403 StringRef DisplayName = SP->getName().split('<').first;
405 const DIScope *Scope = SP->getScope();
407 if (const auto *Class = dyn_cast_or_null<DICompositeType>(Scope)) {
408 // If the scope is a DICompositeType, then this must be a method. Member
409 // function types take some special handling, and require access to the
411 TypeIndex ClassType = getTypeIndex(Class);
412 MemberFuncIdRecord MFuncId(ClassType, getMemberFunctionType(SP, Class),
414 TI = TypeTable.writeLeafType(MFuncId);
416 // Otherwise, this must be a free function.
417 TypeIndex ParentScope = getScopeIndex(Scope);
418 FuncIdRecord FuncId(ParentScope, getTypeIndex(SP->getType()), DisplayName);
419 TI = TypeTable.writeLeafType(FuncId);
422 return recordTypeIndexForDINode(SP, TI);
425 static bool isNonTrivial(const DICompositeType *DCTy) {
426 return ((DCTy->getFlags() & DINode::FlagNonTrivial) == DINode::FlagNonTrivial);
429 static FunctionOptions
430 getFunctionOptions(const DISubroutineType *Ty,
431 const DICompositeType *ClassTy = nullptr,
432 StringRef SPName = StringRef("")) {
433 FunctionOptions FO = FunctionOptions::None;
434 const DIType *ReturnTy = nullptr;
435 if (auto TypeArray = Ty->getTypeArray()) {
436 if (TypeArray.size())
437 ReturnTy = TypeArray[0];
440 // Add CxxReturnUdt option to functions that return nontrivial record types
441 // or methods that return record types.
442 if (auto *ReturnDCTy = dyn_cast_or_null<DICompositeType>(ReturnTy))
443 if (isNonTrivial(ReturnDCTy) || ClassTy)
444 FO |= FunctionOptions::CxxReturnUdt;
446 // DISubroutineType is unnamed. Use DISubprogram's i.e. SPName in comparison.
447 if (ClassTy && isNonTrivial(ClassTy) && SPName == ClassTy->getName()) {
448 FO |= FunctionOptions::Constructor;
450 // TODO: put the FunctionOptions::ConstructorWithVirtualBases flag.
456 TypeIndex CodeViewDebug::getMemberFunctionType(const DISubprogram *SP,
457 const DICompositeType *Class) {
458 // Always use the method declaration as the key for the function type. The
459 // method declaration contains the this adjustment.
460 if (SP->getDeclaration())
461 SP = SP->getDeclaration();
462 assert(!SP->getDeclaration() && "should use declaration as key");
464 // Key the MemberFunctionRecord into the map as {SP, Class}. It won't collide
465 // with the MemberFuncIdRecord, which is keyed in as {SP, nullptr}.
466 auto I = TypeIndices.find({SP, Class});
467 if (I != TypeIndices.end())
470 // Make sure complete type info for the class is emitted *after* the member
471 // function type, as the complete class type is likely to reference this
472 // member function type.
473 TypeLoweringScope S(*this);
474 const bool IsStaticMethod = (SP->getFlags() & DINode::FlagStaticMember) != 0;
476 FunctionOptions FO = getFunctionOptions(SP->getType(), Class, SP->getName());
477 TypeIndex TI = lowerTypeMemberFunction(
478 SP->getType(), Class, SP->getThisAdjustment(), IsStaticMethod, FO);
479 return recordTypeIndexForDINode(SP, TI, Class);
482 TypeIndex CodeViewDebug::recordTypeIndexForDINode(const DINode *Node,
484 const DIType *ClassTy) {
485 auto InsertResult = TypeIndices.insert({{Node, ClassTy}, TI});
487 assert(InsertResult.second && "DINode was already assigned a type index");
491 unsigned CodeViewDebug::getPointerSizeInBytes() {
492 return MMI->getModule()->getDataLayout().getPointerSizeInBits() / 8;
495 void CodeViewDebug::recordLocalVariable(LocalVariable &&Var,
496 const LexicalScope *LS) {
497 if (const DILocation *InlinedAt = LS->getInlinedAt()) {
498 // This variable was inlined. Associate it with the InlineSite.
499 const DISubprogram *Inlinee = Var.DIVar->getScope()->getSubprogram();
500 InlineSite &Site = getInlineSite(InlinedAt, Inlinee);
501 Site.InlinedLocals.emplace_back(Var);
503 // This variable goes into the corresponding lexical scope.
504 ScopeVariables[LS].emplace_back(Var);
508 static void addLocIfNotPresent(SmallVectorImpl<const DILocation *> &Locs,
509 const DILocation *Loc) {
510 auto B = Locs.begin(), E = Locs.end();
511 if (std::find(B, E, Loc) == E)
515 void CodeViewDebug::maybeRecordLocation(const DebugLoc &DL,
516 const MachineFunction *MF) {
517 // Skip this instruction if it has the same location as the previous one.
518 if (!DL || DL == PrevInstLoc)
521 const DIScope *Scope = DL.get()->getScope();
525 // Skip this line if it is longer than the maximum we can record.
526 LineInfo LI(DL.getLine(), DL.getLine(), /*IsStatement=*/true);
527 if (LI.getStartLine() != DL.getLine() || LI.isAlwaysStepInto() ||
528 LI.isNeverStepInto())
531 ColumnInfo CI(DL.getCol(), /*EndColumn=*/0);
532 if (CI.getStartColumn() != DL.getCol())
535 if (!CurFn->HaveLineInfo)
536 CurFn->HaveLineInfo = true;
538 if (PrevInstLoc.get() && PrevInstLoc->getFile() == DL->getFile())
539 FileId = CurFn->LastFileId;
541 FileId = CurFn->LastFileId = maybeRecordFile(DL->getFile());
544 unsigned FuncId = CurFn->FuncId;
545 if (const DILocation *SiteLoc = DL->getInlinedAt()) {
546 const DILocation *Loc = DL.get();
548 // If this location was actually inlined from somewhere else, give it the ID
549 // of the inline call site.
551 getInlineSite(SiteLoc, Loc->getScope()->getSubprogram()).SiteFuncId;
553 // Ensure we have links in the tree of inline call sites.
554 bool FirstLoc = true;
555 while ((SiteLoc = Loc->getInlinedAt())) {
557 getInlineSite(SiteLoc, Loc->getScope()->getSubprogram());
559 addLocIfNotPresent(Site.ChildSites, Loc);
563 addLocIfNotPresent(CurFn->ChildSites, Loc);
566 OS.emitCVLocDirective(FuncId, FileId, DL.getLine(), DL.getCol(),
567 /*PrologueEnd=*/false, /*IsStmt=*/false,
568 DL->getFilename(), SMLoc());
571 void CodeViewDebug::emitCodeViewMagicVersion() {
572 OS.emitValueToAlignment(4);
573 OS.AddComment("Debug section magic");
574 OS.emitInt32(COFF::DEBUG_SECTION_MAGIC);
577 void CodeViewDebug::endModule() {
578 if (!Asm || !MMI->hasDebugInfo())
581 assert(Asm != nullptr);
583 // The COFF .debug$S section consists of several subsections, each starting
584 // with a 4-byte control code (e.g. 0xF1, 0xF2, etc) and then a 4-byte length
585 // of the payload followed by the payload itself. The subsections are 4-byte
588 // Use the generic .debug$S section, and make a subsection for all the inlined
590 switchToDebugSectionForSymbol(nullptr);
592 MCSymbol *CompilerInfo = beginCVSubsection(DebugSubsectionKind::Symbols);
593 emitCompilerInformation();
594 endCVSubsection(CompilerInfo);
596 emitInlineeLinesSubsection();
598 // Emit per-function debug information.
599 for (auto &P : FnDebugInfo)
600 if (!P.first->isDeclarationForLinker())
601 emitDebugInfoForFunction(P.first, *P.second);
603 // Emit global variable debug information.
604 setCurrentSubprogram(nullptr);
605 emitDebugInfoForGlobals();
607 // Emit retained types.
608 emitDebugInfoForRetainedTypes();
610 // Switch back to the generic .debug$S section after potentially processing
611 // comdat symbol sections.
612 switchToDebugSectionForSymbol(nullptr);
614 // Emit UDT records for any types used by global variables.
615 if (!GlobalUDTs.empty()) {
616 MCSymbol *SymbolsEnd = beginCVSubsection(DebugSubsectionKind::Symbols);
617 emitDebugInfoForUDTs(GlobalUDTs);
618 endCVSubsection(SymbolsEnd);
621 // This subsection holds a file index to offset in string table table.
622 OS.AddComment("File index to string table offset subsection");
623 OS.emitCVFileChecksumsDirective();
625 // This subsection holds the string table.
626 OS.AddComment("String table");
627 OS.emitCVStringTableDirective();
629 // Emit S_BUILDINFO, which points to LF_BUILDINFO. Put this in its own symbol
630 // subsection in the generic .debug$S section at the end. There is no
631 // particular reason for this ordering other than to match MSVC.
634 // Emit type information and hashes last, so that any types we translate while
635 // emitting function info are included.
636 emitTypeInformation();
638 if (EmitDebugGlobalHashes)
639 emitTypeGlobalHashes();
645 emitNullTerminatedSymbolName(MCStreamer &OS, StringRef S,
646 unsigned MaxFixedRecordLength = 0xF00) {
647 // The maximum CV record length is 0xFF00. Most of the strings we emit appear
648 // after a fixed length portion of the record. The fixed length portion should
649 // always be less than 0xF00 (3840) bytes, so truncate the string so that the
650 // overall record size is less than the maximum allowed.
651 SmallString<32> NullTerminatedString(
652 S.take_front(MaxRecordLength - MaxFixedRecordLength - 1));
653 NullTerminatedString.push_back('\0');
654 OS.emitBytes(NullTerminatedString);
657 void CodeViewDebug::emitTypeInformation() {
658 if (TypeTable.empty())
661 // Start the .debug$T or .debug$P section with 0x4.
662 OS.SwitchSection(Asm->getObjFileLowering().getCOFFDebugTypesSection());
663 emitCodeViewMagicVersion();
665 TypeTableCollection Table(TypeTable.records());
666 TypeVisitorCallbackPipeline Pipeline;
668 // To emit type record using Codeview MCStreamer adapter
669 CVMCAdapter CVMCOS(OS, Table);
670 TypeRecordMapping typeMapping(CVMCOS);
671 Pipeline.addCallbackToPipeline(typeMapping);
673 Optional<TypeIndex> B = Table.getFirst();
675 // This will fail if the record data is invalid.
676 CVType Record = Table.getType(*B);
678 Error E = codeview::visitTypeRecord(Record, *B, Pipeline);
681 logAllUnhandledErrors(std::move(E), errs(), "error: ");
682 llvm_unreachable("produced malformed type record");
685 B = Table.getNext(*B);
689 void CodeViewDebug::emitTypeGlobalHashes() {
690 if (TypeTable.empty())
693 // Start the .debug$H section with the version and hash algorithm, currently
694 // hardcoded to version 0, SHA1.
695 OS.SwitchSection(Asm->getObjFileLowering().getCOFFGlobalTypeHashesSection());
697 OS.emitValueToAlignment(4);
698 OS.AddComment("Magic");
699 OS.emitInt32(COFF::DEBUG_HASHES_SECTION_MAGIC);
700 OS.AddComment("Section Version");
702 OS.AddComment("Hash Algorithm");
703 OS.emitInt16(uint16_t(GlobalTypeHashAlg::SHA1_8));
705 TypeIndex TI(TypeIndex::FirstNonSimpleIndex);
706 for (const auto &GHR : TypeTable.hashes()) {
707 if (OS.isVerboseAsm()) {
708 // Emit an EOL-comment describing which TypeIndex this hash corresponds
709 // to, as well as the stringified SHA1 hash.
710 SmallString<32> Comment;
711 raw_svector_ostream CommentOS(Comment);
712 CommentOS << formatv("{0:X+} [{1}]", TI.getIndex(), GHR);
713 OS.AddComment(Comment);
716 assert(GHR.Hash.size() == 8);
717 StringRef S(reinterpret_cast<const char *>(GHR.Hash.data()),
719 OS.emitBinaryData(S);
723 static SourceLanguage MapDWLangToCVLang(unsigned DWLang) {
725 case dwarf::DW_LANG_C:
726 case dwarf::DW_LANG_C89:
727 case dwarf::DW_LANG_C99:
728 case dwarf::DW_LANG_C11:
729 case dwarf::DW_LANG_ObjC:
730 return SourceLanguage::C;
731 case dwarf::DW_LANG_C_plus_plus:
732 case dwarf::DW_LANG_C_plus_plus_03:
733 case dwarf::DW_LANG_C_plus_plus_11:
734 case dwarf::DW_LANG_C_plus_plus_14:
735 return SourceLanguage::Cpp;
736 case dwarf::DW_LANG_Fortran77:
737 case dwarf::DW_LANG_Fortran90:
738 case dwarf::DW_LANG_Fortran03:
739 case dwarf::DW_LANG_Fortran08:
740 return SourceLanguage::Fortran;
741 case dwarf::DW_LANG_Pascal83:
742 return SourceLanguage::Pascal;
743 case dwarf::DW_LANG_Cobol74:
744 case dwarf::DW_LANG_Cobol85:
745 return SourceLanguage::Cobol;
746 case dwarf::DW_LANG_Java:
747 return SourceLanguage::Java;
748 case dwarf::DW_LANG_D:
749 return SourceLanguage::D;
750 case dwarf::DW_LANG_Swift:
751 return SourceLanguage::Swift;
753 // There's no CodeView representation for this language, and CV doesn't
754 // have an "unknown" option for the language field, so we'll use MASM,
755 // as it's very low level.
756 return SourceLanguage::Masm;
764 } // end anonymous namespace
766 // Takes a StringRef like "clang 4.0.0.0 (other nonsense 123)" and parses out
767 // the version number.
768 static Version parseVersion(StringRef Name) {
771 for (const char C : Name) {
774 V.Part[N] += C - '0';
775 } else if (C == '.') {
785 void CodeViewDebug::emitCompilerInformation() {
786 MCSymbol *CompilerEnd = beginSymbolRecord(SymbolKind::S_COMPILE3);
789 NamedMDNode *CUs = MMI->getModule()->getNamedMetadata("llvm.dbg.cu");
790 const MDNode *Node = *CUs->operands().begin();
791 const auto *CU = cast<DICompileUnit>(Node);
793 // The low byte of the flags indicates the source language.
794 Flags = MapDWLangToCVLang(CU->getSourceLanguage());
795 // TODO: Figure out which other flags need to be set.
797 OS.AddComment("Flags and language");
800 OS.AddComment("CPUType");
801 OS.emitInt16(static_cast<uint64_t>(TheCPU));
803 StringRef CompilerVersion = CU->getProducer();
804 Version FrontVer = parseVersion(CompilerVersion);
805 OS.AddComment("Frontend version");
806 for (int N = 0; N < 4; ++N)
807 OS.emitInt16(FrontVer.Part[N]);
809 // Some Microsoft tools, like Binscope, expect a backend version number of at
810 // least 8.something, so we'll coerce the LLVM version into a form that
811 // guarantees it'll be big enough without really lying about the version.
812 int Major = 1000 * LLVM_VERSION_MAJOR +
813 10 * LLVM_VERSION_MINOR +
815 // Clamp it for builds that use unusually large version numbers.
816 Major = std::min<int>(Major, std::numeric_limits<uint16_t>::max());
817 Version BackVer = {{ Major, 0, 0, 0 }};
818 OS.AddComment("Backend version");
819 for (int N = 0; N < 4; ++N)
820 OS.emitInt16(BackVer.Part[N]);
822 OS.AddComment("Null-terminated compiler version string");
823 emitNullTerminatedSymbolName(OS, CompilerVersion);
825 endSymbolRecord(CompilerEnd);
828 static TypeIndex getStringIdTypeIdx(GlobalTypeTableBuilder &TypeTable,
830 StringIdRecord SIR(TypeIndex(0x0), S);
831 return TypeTable.writeLeafType(SIR);
834 void CodeViewDebug::emitBuildInfo() {
835 // First, make LF_BUILDINFO. It's a sequence of strings with various bits of
836 // build info. The known prefix is:
837 // - Absolute path of current directory
839 // - Main source file path, relative to CWD or absolute
840 // - Type server PDB file
841 // - Canonical compiler command line
842 // If frontend and backend compilation are separated (think llc or LTO), it's
843 // not clear if the compiler path should refer to the executable for the
844 // frontend or the backend. Leave it blank for now.
845 TypeIndex BuildInfoArgs[BuildInfoRecord::MaxArgs] = {};
846 NamedMDNode *CUs = MMI->getModule()->getNamedMetadata("llvm.dbg.cu");
847 const MDNode *Node = *CUs->operands().begin(); // FIXME: Multiple CUs.
848 const auto *CU = cast<DICompileUnit>(Node);
849 const DIFile *MainSourceFile = CU->getFile();
850 BuildInfoArgs[BuildInfoRecord::CurrentDirectory] =
851 getStringIdTypeIdx(TypeTable, MainSourceFile->getDirectory());
852 BuildInfoArgs[BuildInfoRecord::SourceFile] =
853 getStringIdTypeIdx(TypeTable, MainSourceFile->getFilename());
854 // FIXME: Path to compiler and command line. PDB is intentionally blank unless
855 // we implement /Zi type servers.
856 BuildInfoRecord BIR(BuildInfoArgs);
857 TypeIndex BuildInfoIndex = TypeTable.writeLeafType(BIR);
859 // Make a new .debug$S subsection for the S_BUILDINFO record, which points
860 // from the module symbols into the type stream.
861 MCSymbol *BISubsecEnd = beginCVSubsection(DebugSubsectionKind::Symbols);
862 MCSymbol *BIEnd = beginSymbolRecord(SymbolKind::S_BUILDINFO);
863 OS.AddComment("LF_BUILDINFO index");
864 OS.emitInt32(BuildInfoIndex.getIndex());
865 endSymbolRecord(BIEnd);
866 endCVSubsection(BISubsecEnd);
869 void CodeViewDebug::emitInlineeLinesSubsection() {
870 if (InlinedSubprograms.empty())
873 OS.AddComment("Inlinee lines subsection");
874 MCSymbol *InlineEnd = beginCVSubsection(DebugSubsectionKind::InlineeLines);
876 // We emit the checksum info for files. This is used by debuggers to
877 // determine if a pdb matches the source before loading it. Visual Studio,
878 // for instance, will display a warning that the breakpoints are not valid if
879 // the pdb does not match the source.
880 OS.AddComment("Inlinee lines signature");
881 OS.emitInt32(unsigned(InlineeLinesSignature::Normal));
883 for (const DISubprogram *SP : InlinedSubprograms) {
884 assert(TypeIndices.count({SP, nullptr}));
885 TypeIndex InlineeIdx = TypeIndices[{SP, nullptr}];
888 unsigned FileId = maybeRecordFile(SP->getFile());
889 OS.AddComment("Inlined function " + SP->getName() + " starts at " +
890 SP->getFilename() + Twine(':') + Twine(SP->getLine()));
892 OS.AddComment("Type index of inlined function");
893 OS.emitInt32(InlineeIdx.getIndex());
894 OS.AddComment("Offset into filechecksum table");
895 OS.emitCVFileChecksumOffsetDirective(FileId);
896 OS.AddComment("Starting line number");
897 OS.emitInt32(SP->getLine());
900 endCVSubsection(InlineEnd);
903 void CodeViewDebug::emitInlinedCallSite(const FunctionInfo &FI,
904 const DILocation *InlinedAt,
905 const InlineSite &Site) {
906 assert(TypeIndices.count({Site.Inlinee, nullptr}));
907 TypeIndex InlineeIdx = TypeIndices[{Site.Inlinee, nullptr}];
910 MCSymbol *InlineEnd = beginSymbolRecord(SymbolKind::S_INLINESITE);
912 OS.AddComment("PtrParent");
914 OS.AddComment("PtrEnd");
916 OS.AddComment("Inlinee type index");
917 OS.emitInt32(InlineeIdx.getIndex());
919 unsigned FileId = maybeRecordFile(Site.Inlinee->getFile());
920 unsigned StartLineNum = Site.Inlinee->getLine();
922 OS.emitCVInlineLinetableDirective(Site.SiteFuncId, FileId, StartLineNum,
925 endSymbolRecord(InlineEnd);
927 emitLocalVariableList(FI, Site.InlinedLocals);
929 // Recurse on child inlined call sites before closing the scope.
930 for (const DILocation *ChildSite : Site.ChildSites) {
931 auto I = FI.InlineSites.find(ChildSite);
932 assert(I != FI.InlineSites.end() &&
933 "child site not in function inline site map");
934 emitInlinedCallSite(FI, ChildSite, I->second);
938 emitEndSymbolRecord(SymbolKind::S_INLINESITE_END);
941 void CodeViewDebug::switchToDebugSectionForSymbol(const MCSymbol *GVSym) {
942 // If we have a symbol, it may be in a section that is COMDAT. If so, find the
943 // comdat key. A section may be comdat because of -ffunction-sections or
944 // because it is comdat in the IR.
945 MCSectionCOFF *GVSec =
946 GVSym ? dyn_cast<MCSectionCOFF>(&GVSym->getSection()) : nullptr;
947 const MCSymbol *KeySym = GVSec ? GVSec->getCOMDATSymbol() : nullptr;
949 MCSectionCOFF *DebugSec = cast<MCSectionCOFF>(
950 Asm->getObjFileLowering().getCOFFDebugSymbolsSection());
951 DebugSec = OS.getContext().getAssociativeCOFFSection(DebugSec, KeySym);
953 OS.SwitchSection(DebugSec);
955 // Emit the magic version number if this is the first time we've switched to
957 if (ComdatDebugSections.insert(DebugSec).second)
958 emitCodeViewMagicVersion();
961 // Emit an S_THUNK32/S_END symbol pair for a thunk routine.
962 // The only supported thunk ordinal is currently the standard type.
963 void CodeViewDebug::emitDebugInfoForThunk(const Function *GV,
965 const MCSymbol *Fn) {
966 std::string FuncName =
967 std::string(GlobalValue::dropLLVMManglingEscape(GV->getName()));
968 const ThunkOrdinal ordinal = ThunkOrdinal::Standard; // Only supported kind.
970 OS.AddComment("Symbol subsection for " + Twine(FuncName));
971 MCSymbol *SymbolsEnd = beginCVSubsection(DebugSubsectionKind::Symbols);
974 MCSymbol *ThunkRecordEnd = beginSymbolRecord(SymbolKind::S_THUNK32);
975 OS.AddComment("PtrParent");
977 OS.AddComment("PtrEnd");
979 OS.AddComment("PtrNext");
981 OS.AddComment("Thunk section relative address");
982 OS.EmitCOFFSecRel32(Fn, /*Offset=*/0);
983 OS.AddComment("Thunk section index");
984 OS.EmitCOFFSectionIndex(Fn);
985 OS.AddComment("Code size");
986 OS.emitAbsoluteSymbolDiff(FI.End, Fn, 2);
987 OS.AddComment("Ordinal");
988 OS.emitInt8(unsigned(ordinal));
989 OS.AddComment("Function name");
990 emitNullTerminatedSymbolName(OS, FuncName);
991 // Additional fields specific to the thunk ordinal would go here.
992 endSymbolRecord(ThunkRecordEnd);
994 // Local variables/inlined routines are purposely omitted here. The point of
995 // marking this as a thunk is so Visual Studio will NOT stop in this routine.
997 // Emit S_PROC_ID_END
998 emitEndSymbolRecord(SymbolKind::S_PROC_ID_END);
1000 endCVSubsection(SymbolsEnd);
1003 void CodeViewDebug::emitDebugInfoForFunction(const Function *GV,
1005 // For each function there is a separate subsection which holds the PC to
1007 const MCSymbol *Fn = Asm->getSymbol(GV);
1010 // Switch to the to a comdat section, if appropriate.
1011 switchToDebugSectionForSymbol(Fn);
1013 std::string FuncName;
1014 auto *SP = GV->getSubprogram();
1016 setCurrentSubprogram(SP);
1018 if (SP->isThunk()) {
1019 emitDebugInfoForThunk(GV, FI, Fn);
1023 // If we have a display name, build the fully qualified name by walking the
1025 if (!SP->getName().empty())
1026 FuncName = getFullyQualifiedName(SP->getScope(), SP->getName());
1028 // If our DISubprogram name is empty, use the mangled name.
1029 if (FuncName.empty())
1030 FuncName = std::string(GlobalValue::dropLLVMManglingEscape(GV->getName()));
1032 // Emit FPO data, but only on 32-bit x86. No other platforms use it.
1033 if (Triple(MMI->getModule()->getTargetTriple()).getArch() == Triple::x86)
1034 OS.EmitCVFPOData(Fn);
1036 // Emit a symbol subsection, required by VS2012+ to find function boundaries.
1037 OS.AddComment("Symbol subsection for " + Twine(FuncName));
1038 MCSymbol *SymbolsEnd = beginCVSubsection(DebugSubsectionKind::Symbols);
1040 SymbolKind ProcKind = GV->hasLocalLinkage() ? SymbolKind::S_LPROC32_ID
1041 : SymbolKind::S_GPROC32_ID;
1042 MCSymbol *ProcRecordEnd = beginSymbolRecord(ProcKind);
1044 // These fields are filled in by tools like CVPACK which run after the fact.
1045 OS.AddComment("PtrParent");
1047 OS.AddComment("PtrEnd");
1049 OS.AddComment("PtrNext");
1051 // This is the important bit that tells the debugger where the function
1052 // code is located and what's its size:
1053 OS.AddComment("Code size");
1054 OS.emitAbsoluteSymbolDiff(FI.End, Fn, 4);
1055 OS.AddComment("Offset after prologue");
1057 OS.AddComment("Offset before epilogue");
1059 OS.AddComment("Function type index");
1060 OS.emitInt32(getFuncIdForSubprogram(GV->getSubprogram()).getIndex());
1061 OS.AddComment("Function section relative address");
1062 OS.EmitCOFFSecRel32(Fn, /*Offset=*/0);
1063 OS.AddComment("Function section index");
1064 OS.EmitCOFFSectionIndex(Fn);
1065 OS.AddComment("Flags");
1067 // Emit the function display name as a null-terminated string.
1068 OS.AddComment("Function name");
1069 // Truncate the name so we won't overflow the record length field.
1070 emitNullTerminatedSymbolName(OS, FuncName);
1071 endSymbolRecord(ProcRecordEnd);
1073 MCSymbol *FrameProcEnd = beginSymbolRecord(SymbolKind::S_FRAMEPROC);
1074 // Subtract out the CSR size since MSVC excludes that and we include it.
1075 OS.AddComment("FrameSize");
1076 OS.emitInt32(FI.FrameSize - FI.CSRSize);
1077 OS.AddComment("Padding");
1079 OS.AddComment("Offset of padding");
1081 OS.AddComment("Bytes of callee saved registers");
1082 OS.emitInt32(FI.CSRSize);
1083 OS.AddComment("Exception handler offset");
1085 OS.AddComment("Exception handler section");
1087 OS.AddComment("Flags (defines frame register)");
1088 OS.emitInt32(uint32_t(FI.FrameProcOpts));
1089 endSymbolRecord(FrameProcEnd);
1091 emitLocalVariableList(FI, FI.Locals);
1092 emitGlobalVariableList(FI.Globals);
1093 emitLexicalBlockList(FI.ChildBlocks, FI);
1095 // Emit inlined call site information. Only emit functions inlined directly
1096 // into the parent function. We'll emit the other sites recursively as part
1097 // of their parent inline site.
1098 for (const DILocation *InlinedAt : FI.ChildSites) {
1099 auto I = FI.InlineSites.find(InlinedAt);
1100 assert(I != FI.InlineSites.end() &&
1101 "child site not in function inline site map");
1102 emitInlinedCallSite(FI, InlinedAt, I->second);
1105 for (auto Annot : FI.Annotations) {
1106 MCSymbol *Label = Annot.first;
1107 MDTuple *Strs = cast<MDTuple>(Annot.second);
1108 MCSymbol *AnnotEnd = beginSymbolRecord(SymbolKind::S_ANNOTATION);
1109 OS.EmitCOFFSecRel32(Label, /*Offset=*/0);
1110 // FIXME: Make sure we don't overflow the max record size.
1111 OS.EmitCOFFSectionIndex(Label);
1112 OS.emitInt16(Strs->getNumOperands());
1113 for (Metadata *MD : Strs->operands()) {
1114 // MDStrings are null terminated, so we can do EmitBytes and get the
1115 // nice .asciz directive.
1116 StringRef Str = cast<MDString>(MD)->getString();
1117 assert(Str.data()[Str.size()] == '\0' && "non-nullterminated MDString");
1118 OS.emitBytes(StringRef(Str.data(), Str.size() + 1));
1120 endSymbolRecord(AnnotEnd);
1123 for (auto HeapAllocSite : FI.HeapAllocSites) {
1124 const MCSymbol *BeginLabel = std::get<0>(HeapAllocSite);
1125 const MCSymbol *EndLabel = std::get<1>(HeapAllocSite);
1126 const DIType *DITy = std::get<2>(HeapAllocSite);
1127 MCSymbol *HeapAllocEnd = beginSymbolRecord(SymbolKind::S_HEAPALLOCSITE);
1128 OS.AddComment("Call site offset");
1129 OS.EmitCOFFSecRel32(BeginLabel, /*Offset=*/0);
1130 OS.AddComment("Call site section index");
1131 OS.EmitCOFFSectionIndex(BeginLabel);
1132 OS.AddComment("Call instruction length");
1133 OS.emitAbsoluteSymbolDiff(EndLabel, BeginLabel, 2);
1134 OS.AddComment("Type index");
1135 OS.emitInt32(getCompleteTypeIndex(DITy).getIndex());
1136 endSymbolRecord(HeapAllocEnd);
1140 emitDebugInfoForUDTs(LocalUDTs);
1142 // We're done with this function.
1143 emitEndSymbolRecord(SymbolKind::S_PROC_ID_END);
1145 endCVSubsection(SymbolsEnd);
1147 // We have an assembler directive that takes care of the whole line table.
1148 OS.emitCVLinetableDirective(FI.FuncId, Fn, FI.End);
1151 CodeViewDebug::LocalVarDefRange
1152 CodeViewDebug::createDefRangeMem(uint16_t CVRegister, int Offset) {
1153 LocalVarDefRange DR;
1155 DR.DataOffset = Offset;
1156 assert(DR.DataOffset == Offset && "truncation");
1158 DR.StructOffset = 0;
1159 DR.CVRegister = CVRegister;
1163 void CodeViewDebug::collectVariableInfoFromMFTable(
1164 DenseSet<InlinedEntity> &Processed) {
1165 const MachineFunction &MF = *Asm->MF;
1166 const TargetSubtargetInfo &TSI = MF.getSubtarget();
1167 const TargetFrameLowering *TFI = TSI.getFrameLowering();
1168 const TargetRegisterInfo *TRI = TSI.getRegisterInfo();
1170 for (const MachineFunction::VariableDbgInfo &VI : MF.getVariableDbgInfo()) {
1173 assert(VI.Var->isValidLocationForIntrinsic(VI.Loc) &&
1174 "Expected inlined-at fields to agree");
1176 Processed.insert(InlinedEntity(VI.Var, VI.Loc->getInlinedAt()));
1177 LexicalScope *Scope = LScopes.findLexicalScope(VI.Loc);
1179 // If variable scope is not found then skip this variable.
1183 // If the variable has an attached offset expression, extract it.
1184 // FIXME: Try to handle DW_OP_deref as well.
1185 int64_t ExprOffset = 0;
1188 // If there is one DW_OP_deref element, use offset of 0 and keep going.
1189 if (VI.Expr->getNumElements() == 1 &&
1190 VI.Expr->getElement(0) == llvm::dwarf::DW_OP_deref)
1192 else if (!VI.Expr->extractIfOffset(ExprOffset))
1196 // Get the frame register used and the offset.
1198 int FrameOffset = TFI->getFrameIndexReference(*Asm->MF, VI.Slot, FrameReg);
1199 uint16_t CVReg = TRI->getCodeViewRegNum(FrameReg);
1201 // Calculate the label ranges.
1202 LocalVarDefRange DefRange =
1203 createDefRangeMem(CVReg, FrameOffset + ExprOffset);
1205 for (const InsnRange &Range : Scope->getRanges()) {
1206 const MCSymbol *Begin = getLabelBeforeInsn(Range.first);
1207 const MCSymbol *End = getLabelAfterInsn(Range.second);
1208 End = End ? End : Asm->getFunctionEnd();
1209 DefRange.Ranges.emplace_back(Begin, End);
1214 Var.DefRanges.emplace_back(std::move(DefRange));
1216 Var.UseReferenceType = true;
1218 recordLocalVariable(std::move(Var), Scope);
1222 static bool canUseReferenceType(const DbgVariableLocation &Loc) {
1223 return !Loc.LoadChain.empty() && Loc.LoadChain.back() == 0;
1226 static bool needsReferenceType(const DbgVariableLocation &Loc) {
1227 return Loc.LoadChain.size() == 2 && Loc.LoadChain.back() == 0;
1230 void CodeViewDebug::calculateRanges(
1231 LocalVariable &Var, const DbgValueHistoryMap::Entries &Entries) {
1232 const TargetRegisterInfo *TRI = Asm->MF->getSubtarget().getRegisterInfo();
1234 // Calculate the definition ranges.
1235 for (auto I = Entries.begin(), E = Entries.end(); I != E; ++I) {
1236 const auto &Entry = *I;
1237 if (!Entry.isDbgValue())
1239 const MachineInstr *DVInst = Entry.getInstr();
1240 assert(DVInst->isDebugValue() && "Invalid History entry");
1241 // FIXME: Find a way to represent constant variables, since they are
1242 // relatively common.
1243 Optional<DbgVariableLocation> Location =
1244 DbgVariableLocation::extractFromMachineInstruction(*DVInst);
1248 // CodeView can only express variables in register and variables in memory
1249 // at a constant offset from a register. However, for variables passed
1250 // indirectly by pointer, it is common for that pointer to be spilled to a
1251 // stack location. For the special case of one offseted load followed by a
1252 // zero offset load (a pointer spilled to the stack), we change the type of
1253 // the local variable from a value type to a reference type. This tricks the
1254 // debugger into doing the load for us.
1255 if (Var.UseReferenceType) {
1256 // We're using a reference type. Drop the last zero offset load.
1257 if (canUseReferenceType(*Location))
1258 Location->LoadChain.pop_back();
1261 } else if (needsReferenceType(*Location)) {
1262 // This location can't be expressed without switching to a reference type.
1263 // Start over using that.
1264 Var.UseReferenceType = true;
1265 Var.DefRanges.clear();
1266 calculateRanges(Var, Entries);
1270 // We can only handle a register or an offseted load of a register.
1271 if (Location->Register == 0 || Location->LoadChain.size() > 1)
1274 LocalVarDefRange DR;
1275 DR.CVRegister = TRI->getCodeViewRegNum(Location->Register);
1276 DR.InMemory = !Location->LoadChain.empty();
1278 !Location->LoadChain.empty() ? Location->LoadChain.back() : 0;
1279 if (Location->FragmentInfo) {
1280 DR.IsSubfield = true;
1281 DR.StructOffset = Location->FragmentInfo->OffsetInBits / 8;
1283 DR.IsSubfield = false;
1284 DR.StructOffset = 0;
1287 if (Var.DefRanges.empty() ||
1288 Var.DefRanges.back().isDifferentLocation(DR)) {
1289 Var.DefRanges.emplace_back(std::move(DR));
1293 // Compute the label range.
1294 const MCSymbol *Begin = getLabelBeforeInsn(Entry.getInstr());
1295 const MCSymbol *End;
1296 if (Entry.getEndIndex() != DbgValueHistoryMap::NoEntry) {
1297 auto &EndingEntry = Entries[Entry.getEndIndex()];
1298 End = EndingEntry.isDbgValue()
1299 ? getLabelBeforeInsn(EndingEntry.getInstr())
1300 : getLabelAfterInsn(EndingEntry.getInstr());
1302 End = Asm->getFunctionEnd();
1304 // If the last range end is our begin, just extend the last range.
1305 // Otherwise make a new range.
1306 SmallVectorImpl<std::pair<const MCSymbol *, const MCSymbol *>> &R =
1307 Var.DefRanges.back().Ranges;
1308 if (!R.empty() && R.back().second == Begin)
1309 R.back().second = End;
1311 R.emplace_back(Begin, End);
1313 // FIXME: Do more range combining.
1317 void CodeViewDebug::collectVariableInfo(const DISubprogram *SP) {
1318 DenseSet<InlinedEntity> Processed;
1319 // Grab the variable info that was squirreled away in the MMI side-table.
1320 collectVariableInfoFromMFTable(Processed);
1322 for (const auto &I : DbgValues) {
1323 InlinedEntity IV = I.first;
1324 if (Processed.count(IV))
1326 const DILocalVariable *DIVar = cast<DILocalVariable>(IV.first);
1327 const DILocation *InlinedAt = IV.second;
1329 // Instruction ranges, specifying where IV is accessible.
1330 const auto &Entries = I.second;
1332 LexicalScope *Scope = nullptr;
1334 Scope = LScopes.findInlinedScope(DIVar->getScope(), InlinedAt);
1336 Scope = LScopes.findLexicalScope(DIVar->getScope());
1337 // If variable scope is not found then skip this variable.
1344 calculateRanges(Var, Entries);
1345 recordLocalVariable(std::move(Var), Scope);
1349 void CodeViewDebug::beginFunctionImpl(const MachineFunction *MF) {
1350 const TargetSubtargetInfo &TSI = MF->getSubtarget();
1351 const TargetRegisterInfo *TRI = TSI.getRegisterInfo();
1352 const MachineFrameInfo &MFI = MF->getFrameInfo();
1353 const Function &GV = MF->getFunction();
1354 auto Insertion = FnDebugInfo.insert({&GV, std::make_unique<FunctionInfo>()});
1355 assert(Insertion.second && "function already has info");
1356 CurFn = Insertion.first->second.get();
1357 CurFn->FuncId = NextFuncId++;
1358 CurFn->Begin = Asm->getFunctionBegin();
1360 // The S_FRAMEPROC record reports the stack size, and how many bytes of
1361 // callee-saved registers were used. For targets that don't use a PUSH
1362 // instruction (AArch64), this will be zero.
1363 CurFn->CSRSize = MFI.getCVBytesOfCalleeSavedRegisters();
1364 CurFn->FrameSize = MFI.getStackSize();
1365 CurFn->OffsetAdjustment = MFI.getOffsetAdjustment();
1366 CurFn->HasStackRealignment = TRI->needsStackRealignment(*MF);
1368 // For this function S_FRAMEPROC record, figure out which codeview register
1369 // will be the frame pointer.
1370 CurFn->EncodedParamFramePtrReg = EncodedFramePtrReg::None; // None.
1371 CurFn->EncodedLocalFramePtrReg = EncodedFramePtrReg::None; // None.
1372 if (CurFn->FrameSize > 0) {
1373 if (!TSI.getFrameLowering()->hasFP(*MF)) {
1374 CurFn->EncodedLocalFramePtrReg = EncodedFramePtrReg::StackPtr;
1375 CurFn->EncodedParamFramePtrReg = EncodedFramePtrReg::StackPtr;
1377 // If there is an FP, parameters are always relative to it.
1378 CurFn->EncodedParamFramePtrReg = EncodedFramePtrReg::FramePtr;
1379 if (CurFn->HasStackRealignment) {
1380 // If the stack needs realignment, locals are relative to SP or VFRAME.
1381 CurFn->EncodedLocalFramePtrReg = EncodedFramePtrReg::StackPtr;
1383 // Otherwise, locals are relative to EBP, and we probably have VLAs or
1384 // other stack adjustments.
1385 CurFn->EncodedLocalFramePtrReg = EncodedFramePtrReg::FramePtr;
1390 // Compute other frame procedure options.
1391 FrameProcedureOptions FPO = FrameProcedureOptions::None;
1392 if (MFI.hasVarSizedObjects())
1393 FPO |= FrameProcedureOptions::HasAlloca;
1394 if (MF->exposesReturnsTwice())
1395 FPO |= FrameProcedureOptions::HasSetJmp;
1396 // FIXME: Set HasLongJmp if we ever track that info.
1397 if (MF->hasInlineAsm())
1398 FPO |= FrameProcedureOptions::HasInlineAssembly;
1399 if (GV.hasPersonalityFn()) {
1400 if (isAsynchronousEHPersonality(
1401 classifyEHPersonality(GV.getPersonalityFn())))
1402 FPO |= FrameProcedureOptions::HasStructuredExceptionHandling;
1404 FPO |= FrameProcedureOptions::HasExceptionHandling;
1406 if (GV.hasFnAttribute(Attribute::InlineHint))
1407 FPO |= FrameProcedureOptions::MarkedInline;
1408 if (GV.hasFnAttribute(Attribute::Naked))
1409 FPO |= FrameProcedureOptions::Naked;
1410 if (MFI.hasStackProtectorIndex())
1411 FPO |= FrameProcedureOptions::SecurityChecks;
1412 FPO |= FrameProcedureOptions(uint32_t(CurFn->EncodedLocalFramePtrReg) << 14U);
1413 FPO |= FrameProcedureOptions(uint32_t(CurFn->EncodedParamFramePtrReg) << 16U);
1414 if (Asm->TM.getOptLevel() != CodeGenOpt::None &&
1415 !GV.hasOptSize() && !GV.hasOptNone())
1416 FPO |= FrameProcedureOptions::OptimizedForSpeed;
1417 // FIXME: Set GuardCfg when it is implemented.
1418 CurFn->FrameProcOpts = FPO;
1420 OS.EmitCVFuncIdDirective(CurFn->FuncId);
1422 // Find the end of the function prolog. First known non-DBG_VALUE and
1423 // non-frame setup location marks the beginning of the function body.
1424 // FIXME: is there a simpler a way to do this? Can we just search
1425 // for the first instruction of the function, not the last of the prolog?
1426 DebugLoc PrologEndLoc;
1427 bool EmptyPrologue = true;
1428 for (const auto &MBB : *MF) {
1429 for (const auto &MI : MBB) {
1430 if (!MI.isMetaInstruction() && !MI.getFlag(MachineInstr::FrameSetup) &&
1432 PrologEndLoc = MI.getDebugLoc();
1434 } else if (!MI.isMetaInstruction()) {
1435 EmptyPrologue = false;
1440 // Record beginning of function if we have a non-empty prologue.
1441 if (PrologEndLoc && !EmptyPrologue) {
1442 DebugLoc FnStartDL = PrologEndLoc.getFnDebugLoc();
1443 maybeRecordLocation(FnStartDL, MF);
1446 // Find heap alloc sites and emit labels around them.
1447 for (const auto &MBB : *MF) {
1448 for (const auto &MI : MBB) {
1449 if (MI.getHeapAllocMarker()) {
1450 requestLabelBeforeInsn(&MI);
1451 requestLabelAfterInsn(&MI);
1457 static bool shouldEmitUdt(const DIType *T) {
1461 // MSVC does not emit UDTs for typedefs that are scoped to classes.
1462 if (T->getTag() == dwarf::DW_TAG_typedef) {
1463 if (DIScope *Scope = T->getScope()) {
1464 switch (Scope->getTag()) {
1465 case dwarf::DW_TAG_structure_type:
1466 case dwarf::DW_TAG_class_type:
1467 case dwarf::DW_TAG_union_type:
1474 if (!T || T->isForwardDecl())
1477 const DIDerivedType *DT = dyn_cast<DIDerivedType>(T);
1480 T = DT->getBaseType();
1485 void CodeViewDebug::addToUDTs(const DIType *Ty) {
1486 // Don't record empty UDTs.
1487 if (Ty->getName().empty())
1489 if (!shouldEmitUdt(Ty))
1492 SmallVector<StringRef, 5> ParentScopeNames;
1493 const DISubprogram *ClosestSubprogram =
1494 collectParentScopeNames(Ty->getScope(), ParentScopeNames);
1496 std::string FullyQualifiedName =
1497 formatNestedName(ParentScopeNames, getPrettyScopeName(Ty));
1499 if (ClosestSubprogram == nullptr) {
1500 GlobalUDTs.emplace_back(std::move(FullyQualifiedName), Ty);
1501 } else if (ClosestSubprogram == CurrentSubprogram) {
1502 LocalUDTs.emplace_back(std::move(FullyQualifiedName), Ty);
1505 // TODO: What if the ClosestSubprogram is neither null or the current
1506 // subprogram? Currently, the UDT just gets dropped on the floor.
1508 // The current behavior is not desirable. To get maximal fidelity, we would
1509 // need to perform all type translation before beginning emission of .debug$S
1510 // and then make LocalUDTs a member of FunctionInfo
1513 TypeIndex CodeViewDebug::lowerType(const DIType *Ty, const DIType *ClassTy) {
1514 // Generic dispatch for lowering an unknown type.
1515 switch (Ty->getTag()) {
1516 case dwarf::DW_TAG_array_type:
1517 return lowerTypeArray(cast<DICompositeType>(Ty));
1518 case dwarf::DW_TAG_typedef:
1519 return lowerTypeAlias(cast<DIDerivedType>(Ty));
1520 case dwarf::DW_TAG_base_type:
1521 return lowerTypeBasic(cast<DIBasicType>(Ty));
1522 case dwarf::DW_TAG_pointer_type:
1523 if (cast<DIDerivedType>(Ty)->getName() == "__vtbl_ptr_type")
1524 return lowerTypeVFTableShape(cast<DIDerivedType>(Ty));
1526 case dwarf::DW_TAG_reference_type:
1527 case dwarf::DW_TAG_rvalue_reference_type:
1528 return lowerTypePointer(cast<DIDerivedType>(Ty));
1529 case dwarf::DW_TAG_ptr_to_member_type:
1530 return lowerTypeMemberPointer(cast<DIDerivedType>(Ty));
1531 case dwarf::DW_TAG_restrict_type:
1532 case dwarf::DW_TAG_const_type:
1533 case dwarf::DW_TAG_volatile_type:
1534 // TODO: add support for DW_TAG_atomic_type here
1535 return lowerTypeModifier(cast<DIDerivedType>(Ty));
1536 case dwarf::DW_TAG_subroutine_type:
1538 // The member function type of a member function pointer has no
1540 return lowerTypeMemberFunction(cast<DISubroutineType>(Ty), ClassTy,
1541 /*ThisAdjustment=*/0,
1542 /*IsStaticMethod=*/false);
1544 return lowerTypeFunction(cast<DISubroutineType>(Ty));
1545 case dwarf::DW_TAG_enumeration_type:
1546 return lowerTypeEnum(cast<DICompositeType>(Ty));
1547 case dwarf::DW_TAG_class_type:
1548 case dwarf::DW_TAG_structure_type:
1549 return lowerTypeClass(cast<DICompositeType>(Ty));
1550 case dwarf::DW_TAG_union_type:
1551 return lowerTypeUnion(cast<DICompositeType>(Ty));
1552 case dwarf::DW_TAG_unspecified_type:
1553 if (Ty->getName() == "decltype(nullptr)")
1554 return TypeIndex::NullptrT();
1555 return TypeIndex::None();
1557 // Use the null type index.
1562 TypeIndex CodeViewDebug::lowerTypeAlias(const DIDerivedType *Ty) {
1563 TypeIndex UnderlyingTypeIndex = getTypeIndex(Ty->getBaseType());
1564 StringRef TypeName = Ty->getName();
1568 if (UnderlyingTypeIndex == TypeIndex(SimpleTypeKind::Int32Long) &&
1569 TypeName == "HRESULT")
1570 return TypeIndex(SimpleTypeKind::HResult);
1571 if (UnderlyingTypeIndex == TypeIndex(SimpleTypeKind::UInt16Short) &&
1572 TypeName == "wchar_t")
1573 return TypeIndex(SimpleTypeKind::WideCharacter);
1575 return UnderlyingTypeIndex;
1578 TypeIndex CodeViewDebug::lowerTypeArray(const DICompositeType *Ty) {
1579 const DIType *ElementType = Ty->getBaseType();
1580 TypeIndex ElementTypeIndex = getTypeIndex(ElementType);
1581 // IndexType is size_t, which depends on the bitness of the target.
1582 TypeIndex IndexType = getPointerSizeInBytes() == 8
1583 ? TypeIndex(SimpleTypeKind::UInt64Quad)
1584 : TypeIndex(SimpleTypeKind::UInt32Long);
1586 uint64_t ElementSize = getBaseTypeSize(ElementType) / 8;
1588 // Add subranges to array type.
1589 DINodeArray Elements = Ty->getElements();
1590 for (int i = Elements.size() - 1; i >= 0; --i) {
1591 const DINode *Element = Elements[i];
1592 assert(Element->getTag() == dwarf::DW_TAG_subrange_type);
1594 const DISubrange *Subrange = cast<DISubrange>(Element);
1596 // Calculate the count if either LowerBound is absent or is zero and
1597 // either of Count or UpperBound are constant.
1598 auto *LI = Subrange->getLowerBound().dyn_cast<ConstantInt *>();
1599 if (!Subrange->getRawLowerBound() || (LI && (LI->getSExtValue() == 0))) {
1600 if (auto *CI = Subrange->getCount().dyn_cast<ConstantInt*>())
1601 Count = CI->getSExtValue();
1602 else if (auto *UI = Subrange->getUpperBound().dyn_cast<ConstantInt*>())
1603 Count = UI->getSExtValue() + 1; // LowerBound is zero
1606 // Forward declarations of arrays without a size and VLAs use a count of -1.
1607 // Emit a count of zero in these cases to match what MSVC does for arrays
1608 // without a size. MSVC doesn't support VLAs, so it's not clear what we
1609 // should do for them even if we could distinguish them.
1613 // Update the element size and element type index for subsequent subranges.
1614 ElementSize *= Count;
1616 // If this is the outermost array, use the size from the array. It will be
1617 // more accurate if we had a VLA or an incomplete element type size.
1618 uint64_t ArraySize =
1619 (i == 0 && ElementSize == 0) ? Ty->getSizeInBits() / 8 : ElementSize;
1621 StringRef Name = (i == 0) ? Ty->getName() : "";
1622 ArrayRecord AR(ElementTypeIndex, IndexType, ArraySize, Name);
1623 ElementTypeIndex = TypeTable.writeLeafType(AR);
1626 return ElementTypeIndex;
1629 TypeIndex CodeViewDebug::lowerTypeBasic(const DIBasicType *Ty) {
1631 dwarf::TypeKind Kind;
1634 Kind = static_cast<dwarf::TypeKind>(Ty->getEncoding());
1635 ByteSize = Ty->getSizeInBits() / 8;
1637 SimpleTypeKind STK = SimpleTypeKind::None;
1639 case dwarf::DW_ATE_address:
1642 case dwarf::DW_ATE_boolean:
1644 case 1: STK = SimpleTypeKind::Boolean8; break;
1645 case 2: STK = SimpleTypeKind::Boolean16; break;
1646 case 4: STK = SimpleTypeKind::Boolean32; break;
1647 case 8: STK = SimpleTypeKind::Boolean64; break;
1648 case 16: STK = SimpleTypeKind::Boolean128; break;
1651 case dwarf::DW_ATE_complex_float:
1653 case 2: STK = SimpleTypeKind::Complex16; break;
1654 case 4: STK = SimpleTypeKind::Complex32; break;
1655 case 8: STK = SimpleTypeKind::Complex64; break;
1656 case 10: STK = SimpleTypeKind::Complex80; break;
1657 case 16: STK = SimpleTypeKind::Complex128; break;
1660 case dwarf::DW_ATE_float:
1662 case 2: STK = SimpleTypeKind::Float16; break;
1663 case 4: STK = SimpleTypeKind::Float32; break;
1664 case 6: STK = SimpleTypeKind::Float48; break;
1665 case 8: STK = SimpleTypeKind::Float64; break;
1666 case 10: STK = SimpleTypeKind::Float80; break;
1667 case 16: STK = SimpleTypeKind::Float128; break;
1670 case dwarf::DW_ATE_signed:
1672 case 1: STK = SimpleTypeKind::SignedCharacter; break;
1673 case 2: STK = SimpleTypeKind::Int16Short; break;
1674 case 4: STK = SimpleTypeKind::Int32; break;
1675 case 8: STK = SimpleTypeKind::Int64Quad; break;
1676 case 16: STK = SimpleTypeKind::Int128Oct; break;
1679 case dwarf::DW_ATE_unsigned:
1681 case 1: STK = SimpleTypeKind::UnsignedCharacter; break;
1682 case 2: STK = SimpleTypeKind::UInt16Short; break;
1683 case 4: STK = SimpleTypeKind::UInt32; break;
1684 case 8: STK = SimpleTypeKind::UInt64Quad; break;
1685 case 16: STK = SimpleTypeKind::UInt128Oct; break;
1688 case dwarf::DW_ATE_UTF:
1690 case 2: STK = SimpleTypeKind::Character16; break;
1691 case 4: STK = SimpleTypeKind::Character32; break;
1694 case dwarf::DW_ATE_signed_char:
1696 STK = SimpleTypeKind::SignedCharacter;
1698 case dwarf::DW_ATE_unsigned_char:
1700 STK = SimpleTypeKind::UnsignedCharacter;
1706 // Apply some fixups based on the source-level type name.
1707 if (STK == SimpleTypeKind::Int32 && Ty->getName() == "long int")
1708 STK = SimpleTypeKind::Int32Long;
1709 if (STK == SimpleTypeKind::UInt32 && Ty->getName() == "long unsigned int")
1710 STK = SimpleTypeKind::UInt32Long;
1711 if (STK == SimpleTypeKind::UInt16Short &&
1712 (Ty->getName() == "wchar_t" || Ty->getName() == "__wchar_t"))
1713 STK = SimpleTypeKind::WideCharacter;
1714 if ((STK == SimpleTypeKind::SignedCharacter ||
1715 STK == SimpleTypeKind::UnsignedCharacter) &&
1716 Ty->getName() == "char")
1717 STK = SimpleTypeKind::NarrowCharacter;
1719 return TypeIndex(STK);
1722 TypeIndex CodeViewDebug::lowerTypePointer(const DIDerivedType *Ty,
1723 PointerOptions PO) {
1724 TypeIndex PointeeTI = getTypeIndex(Ty->getBaseType());
1726 // Pointers to simple types without any options can use SimpleTypeMode, rather
1727 // than having a dedicated pointer type record.
1728 if (PointeeTI.isSimple() && PO == PointerOptions::None &&
1729 PointeeTI.getSimpleMode() == SimpleTypeMode::Direct &&
1730 Ty->getTag() == dwarf::DW_TAG_pointer_type) {
1731 SimpleTypeMode Mode = Ty->getSizeInBits() == 64
1732 ? SimpleTypeMode::NearPointer64
1733 : SimpleTypeMode::NearPointer32;
1734 return TypeIndex(PointeeTI.getSimpleKind(), Mode);
1738 Ty->getSizeInBits() == 64 ? PointerKind::Near64 : PointerKind::Near32;
1739 PointerMode PM = PointerMode::Pointer;
1740 switch (Ty->getTag()) {
1741 default: llvm_unreachable("not a pointer tag type");
1742 case dwarf::DW_TAG_pointer_type:
1743 PM = PointerMode::Pointer;
1745 case dwarf::DW_TAG_reference_type:
1746 PM = PointerMode::LValueReference;
1748 case dwarf::DW_TAG_rvalue_reference_type:
1749 PM = PointerMode::RValueReference;
1753 if (Ty->isObjectPointer())
1754 PO |= PointerOptions::Const;
1756 PointerRecord PR(PointeeTI, PK, PM, PO, Ty->getSizeInBits() / 8);
1757 return TypeTable.writeLeafType(PR);
1760 static PointerToMemberRepresentation
1761 translatePtrToMemberRep(unsigned SizeInBytes, bool IsPMF, unsigned Flags) {
1762 // SizeInBytes being zero generally implies that the member pointer type was
1763 // incomplete, which can happen if it is part of a function prototype. In this
1764 // case, use the unknown model instead of the general model.
1766 switch (Flags & DINode::FlagPtrToMemberRep) {
1768 return SizeInBytes == 0 ? PointerToMemberRepresentation::Unknown
1769 : PointerToMemberRepresentation::GeneralFunction;
1770 case DINode::FlagSingleInheritance:
1771 return PointerToMemberRepresentation::SingleInheritanceFunction;
1772 case DINode::FlagMultipleInheritance:
1773 return PointerToMemberRepresentation::MultipleInheritanceFunction;
1774 case DINode::FlagVirtualInheritance:
1775 return PointerToMemberRepresentation::VirtualInheritanceFunction;
1778 switch (Flags & DINode::FlagPtrToMemberRep) {
1780 return SizeInBytes == 0 ? PointerToMemberRepresentation::Unknown
1781 : PointerToMemberRepresentation::GeneralData;
1782 case DINode::FlagSingleInheritance:
1783 return PointerToMemberRepresentation::SingleInheritanceData;
1784 case DINode::FlagMultipleInheritance:
1785 return PointerToMemberRepresentation::MultipleInheritanceData;
1786 case DINode::FlagVirtualInheritance:
1787 return PointerToMemberRepresentation::VirtualInheritanceData;
1790 llvm_unreachable("invalid ptr to member representation");
1793 TypeIndex CodeViewDebug::lowerTypeMemberPointer(const DIDerivedType *Ty,
1794 PointerOptions PO) {
1795 assert(Ty->getTag() == dwarf::DW_TAG_ptr_to_member_type);
1796 bool IsPMF = isa<DISubroutineType>(Ty->getBaseType());
1797 TypeIndex ClassTI = getTypeIndex(Ty->getClassType());
1798 TypeIndex PointeeTI =
1799 getTypeIndex(Ty->getBaseType(), IsPMF ? Ty->getClassType() : nullptr);
1800 PointerKind PK = getPointerSizeInBytes() == 8 ? PointerKind::Near64
1801 : PointerKind::Near32;
1802 PointerMode PM = IsPMF ? PointerMode::PointerToMemberFunction
1803 : PointerMode::PointerToDataMember;
1805 assert(Ty->getSizeInBits() / 8 <= 0xff && "pointer size too big");
1806 uint8_t SizeInBytes = Ty->getSizeInBits() / 8;
1807 MemberPointerInfo MPI(
1808 ClassTI, translatePtrToMemberRep(SizeInBytes, IsPMF, Ty->getFlags()));
1809 PointerRecord PR(PointeeTI, PK, PM, PO, SizeInBytes, MPI);
1810 return TypeTable.writeLeafType(PR);
1813 /// Given a DWARF calling convention, get the CodeView equivalent. If we don't
1814 /// have a translation, use the NearC convention.
1815 static CallingConvention dwarfCCToCodeView(unsigned DwarfCC) {
1817 case dwarf::DW_CC_normal: return CallingConvention::NearC;
1818 case dwarf::DW_CC_BORLAND_msfastcall: return CallingConvention::NearFast;
1819 case dwarf::DW_CC_BORLAND_thiscall: return CallingConvention::ThisCall;
1820 case dwarf::DW_CC_BORLAND_stdcall: return CallingConvention::NearStdCall;
1821 case dwarf::DW_CC_BORLAND_pascal: return CallingConvention::NearPascal;
1822 case dwarf::DW_CC_LLVM_vectorcall: return CallingConvention::NearVector;
1824 return CallingConvention::NearC;
1827 TypeIndex CodeViewDebug::lowerTypeModifier(const DIDerivedType *Ty) {
1828 ModifierOptions Mods = ModifierOptions::None;
1829 PointerOptions PO = PointerOptions::None;
1830 bool IsModifier = true;
1831 const DIType *BaseTy = Ty;
1832 while (IsModifier && BaseTy) {
1833 // FIXME: Need to add DWARF tags for __unaligned and _Atomic
1834 switch (BaseTy->getTag()) {
1835 case dwarf::DW_TAG_const_type:
1836 Mods |= ModifierOptions::Const;
1837 PO |= PointerOptions::Const;
1839 case dwarf::DW_TAG_volatile_type:
1840 Mods |= ModifierOptions::Volatile;
1841 PO |= PointerOptions::Volatile;
1843 case dwarf::DW_TAG_restrict_type:
1844 // Only pointer types be marked with __restrict. There is no known flag
1845 // for __restrict in LF_MODIFIER records.
1846 PO |= PointerOptions::Restrict;
1853 BaseTy = cast<DIDerivedType>(BaseTy)->getBaseType();
1856 // Check if the inner type will use an LF_POINTER record. If so, the
1857 // qualifiers will go in the LF_POINTER record. This comes up for types like
1858 // 'int *const' and 'int *__restrict', not the more common cases like 'const
1861 switch (BaseTy->getTag()) {
1862 case dwarf::DW_TAG_pointer_type:
1863 case dwarf::DW_TAG_reference_type:
1864 case dwarf::DW_TAG_rvalue_reference_type:
1865 return lowerTypePointer(cast<DIDerivedType>(BaseTy), PO);
1866 case dwarf::DW_TAG_ptr_to_member_type:
1867 return lowerTypeMemberPointer(cast<DIDerivedType>(BaseTy), PO);
1873 TypeIndex ModifiedTI = getTypeIndex(BaseTy);
1875 // Return the base type index if there aren't any modifiers. For example, the
1876 // metadata could contain restrict wrappers around non-pointer types.
1877 if (Mods == ModifierOptions::None)
1880 ModifierRecord MR(ModifiedTI, Mods);
1881 return TypeTable.writeLeafType(MR);
1884 TypeIndex CodeViewDebug::lowerTypeFunction(const DISubroutineType *Ty) {
1885 SmallVector<TypeIndex, 8> ReturnAndArgTypeIndices;
1886 for (const DIType *ArgType : Ty->getTypeArray())
1887 ReturnAndArgTypeIndices.push_back(getTypeIndex(ArgType));
1889 // MSVC uses type none for variadic argument.
1890 if (ReturnAndArgTypeIndices.size() > 1 &&
1891 ReturnAndArgTypeIndices.back() == TypeIndex::Void()) {
1892 ReturnAndArgTypeIndices.back() = TypeIndex::None();
1894 TypeIndex ReturnTypeIndex = TypeIndex::Void();
1895 ArrayRef<TypeIndex> ArgTypeIndices = None;
1896 if (!ReturnAndArgTypeIndices.empty()) {
1897 auto ReturnAndArgTypesRef = makeArrayRef(ReturnAndArgTypeIndices);
1898 ReturnTypeIndex = ReturnAndArgTypesRef.front();
1899 ArgTypeIndices = ReturnAndArgTypesRef.drop_front();
1902 ArgListRecord ArgListRec(TypeRecordKind::ArgList, ArgTypeIndices);
1903 TypeIndex ArgListIndex = TypeTable.writeLeafType(ArgListRec);
1905 CallingConvention CC = dwarfCCToCodeView(Ty->getCC());
1907 FunctionOptions FO = getFunctionOptions(Ty);
1908 ProcedureRecord Procedure(ReturnTypeIndex, CC, FO, ArgTypeIndices.size(),
1910 return TypeTable.writeLeafType(Procedure);
1913 TypeIndex CodeViewDebug::lowerTypeMemberFunction(const DISubroutineType *Ty,
1914 const DIType *ClassTy,
1916 bool IsStaticMethod,
1917 FunctionOptions FO) {
1918 // Lower the containing class type.
1919 TypeIndex ClassType = getTypeIndex(ClassTy);
1921 DITypeRefArray ReturnAndArgs = Ty->getTypeArray();
1924 SmallVector<TypeIndex, 8> ArgTypeIndices;
1925 TypeIndex ReturnTypeIndex = TypeIndex::Void();
1926 if (ReturnAndArgs.size() > Index) {
1927 ReturnTypeIndex = getTypeIndex(ReturnAndArgs[Index++]);
1930 // If the first argument is a pointer type and this isn't a static method,
1931 // treat it as the special 'this' parameter, which is encoded separately from
1933 TypeIndex ThisTypeIndex;
1934 if (!IsStaticMethod && ReturnAndArgs.size() > Index) {
1935 if (const DIDerivedType *PtrTy =
1936 dyn_cast_or_null<DIDerivedType>(ReturnAndArgs[Index])) {
1937 if (PtrTy->getTag() == dwarf::DW_TAG_pointer_type) {
1938 ThisTypeIndex = getTypeIndexForThisPtr(PtrTy, Ty);
1944 while (Index < ReturnAndArgs.size())
1945 ArgTypeIndices.push_back(getTypeIndex(ReturnAndArgs[Index++]));
1947 // MSVC uses type none for variadic argument.
1948 if (!ArgTypeIndices.empty() && ArgTypeIndices.back() == TypeIndex::Void())
1949 ArgTypeIndices.back() = TypeIndex::None();
1951 ArgListRecord ArgListRec(TypeRecordKind::ArgList, ArgTypeIndices);
1952 TypeIndex ArgListIndex = TypeTable.writeLeafType(ArgListRec);
1954 CallingConvention CC = dwarfCCToCodeView(Ty->getCC());
1956 MemberFunctionRecord MFR(ReturnTypeIndex, ClassType, ThisTypeIndex, CC, FO,
1957 ArgTypeIndices.size(), ArgListIndex, ThisAdjustment);
1958 return TypeTable.writeLeafType(MFR);
1961 TypeIndex CodeViewDebug::lowerTypeVFTableShape(const DIDerivedType *Ty) {
1962 unsigned VSlotCount =
1963 Ty->getSizeInBits() / (8 * Asm->MAI->getCodePointerSize());
1964 SmallVector<VFTableSlotKind, 4> Slots(VSlotCount, VFTableSlotKind::Near);
1966 VFTableShapeRecord VFTSR(Slots);
1967 return TypeTable.writeLeafType(VFTSR);
1970 static MemberAccess translateAccessFlags(unsigned RecordTag, unsigned Flags) {
1971 switch (Flags & DINode::FlagAccessibility) {
1972 case DINode::FlagPrivate: return MemberAccess::Private;
1973 case DINode::FlagPublic: return MemberAccess::Public;
1974 case DINode::FlagProtected: return MemberAccess::Protected;
1976 // If there was no explicit access control, provide the default for the tag.
1977 return RecordTag == dwarf::DW_TAG_class_type ? MemberAccess::Private
1978 : MemberAccess::Public;
1980 llvm_unreachable("access flags are exclusive");
1983 static MethodOptions translateMethodOptionFlags(const DISubprogram *SP) {
1984 if (SP->isArtificial())
1985 return MethodOptions::CompilerGenerated;
1987 // FIXME: Handle other MethodOptions.
1989 return MethodOptions::None;
1992 static MethodKind translateMethodKindFlags(const DISubprogram *SP,
1994 if (SP->getFlags() & DINode::FlagStaticMember)
1995 return MethodKind::Static;
1997 switch (SP->getVirtuality()) {
1998 case dwarf::DW_VIRTUALITY_none:
2000 case dwarf::DW_VIRTUALITY_virtual:
2001 return Introduced ? MethodKind::IntroducingVirtual : MethodKind::Virtual;
2002 case dwarf::DW_VIRTUALITY_pure_virtual:
2003 return Introduced ? MethodKind::PureIntroducingVirtual
2004 : MethodKind::PureVirtual;
2006 llvm_unreachable("unhandled virtuality case");
2009 return MethodKind::Vanilla;
2012 static TypeRecordKind getRecordKind(const DICompositeType *Ty) {
2013 switch (Ty->getTag()) {
2014 case dwarf::DW_TAG_class_type: return TypeRecordKind::Class;
2015 case dwarf::DW_TAG_structure_type: return TypeRecordKind::Struct;
2017 llvm_unreachable("unexpected tag");
2020 /// Return ClassOptions that should be present on both the forward declaration
2021 /// and the defintion of a tag type.
2022 static ClassOptions getCommonClassOptions(const DICompositeType *Ty) {
2023 ClassOptions CO = ClassOptions::None;
2025 // MSVC always sets this flag, even for local types. Clang doesn't always
2026 // appear to give every type a linkage name, which may be problematic for us.
2027 // FIXME: Investigate the consequences of not following them here.
2028 if (!Ty->getIdentifier().empty())
2029 CO |= ClassOptions::HasUniqueName;
2031 // Put the Nested flag on a type if it appears immediately inside a tag type.
2032 // Do not walk the scope chain. Do not attempt to compute ContainsNestedClass
2033 // here. That flag is only set on definitions, and not forward declarations.
2034 const DIScope *ImmediateScope = Ty->getScope();
2035 if (ImmediateScope && isa<DICompositeType>(ImmediateScope))
2036 CO |= ClassOptions::Nested;
2038 // Put the Scoped flag on function-local types. MSVC puts this flag for enum
2039 // type only when it has an immediate function scope. Clang never puts enums
2040 // inside DILexicalBlock scopes. Enum types, as generated by clang, are
2041 // always in function, class, or file scopes.
2042 if (Ty->getTag() == dwarf::DW_TAG_enumeration_type) {
2043 if (ImmediateScope && isa<DISubprogram>(ImmediateScope))
2044 CO |= ClassOptions::Scoped;
2046 for (const DIScope *Scope = ImmediateScope; Scope != nullptr;
2047 Scope = Scope->getScope()) {
2048 if (isa<DISubprogram>(Scope)) {
2049 CO |= ClassOptions::Scoped;
2058 void CodeViewDebug::addUDTSrcLine(const DIType *Ty, TypeIndex TI) {
2059 switch (Ty->getTag()) {
2060 case dwarf::DW_TAG_class_type:
2061 case dwarf::DW_TAG_structure_type:
2062 case dwarf::DW_TAG_union_type:
2063 case dwarf::DW_TAG_enumeration_type:
2069 if (const auto *File = Ty->getFile()) {
2070 StringIdRecord SIDR(TypeIndex(0x0), getFullFilepath(File));
2071 TypeIndex SIDI = TypeTable.writeLeafType(SIDR);
2073 UdtSourceLineRecord USLR(TI, SIDI, Ty->getLine());
2074 TypeTable.writeLeafType(USLR);
2078 TypeIndex CodeViewDebug::lowerTypeEnum(const DICompositeType *Ty) {
2079 ClassOptions CO = getCommonClassOptions(Ty);
2081 unsigned EnumeratorCount = 0;
2083 if (Ty->isForwardDecl()) {
2084 CO |= ClassOptions::ForwardReference;
2086 ContinuationRecordBuilder ContinuationBuilder;
2087 ContinuationBuilder.begin(ContinuationRecordKind::FieldList);
2088 for (const DINode *Element : Ty->getElements()) {
2089 // We assume that the frontend provides all members in source declaration
2090 // order, which is what MSVC does.
2091 if (auto *Enumerator = dyn_cast_or_null<DIEnumerator>(Element)) {
2092 EnumeratorRecord ER(MemberAccess::Public,
2093 APSInt(Enumerator->getValue(), true),
2094 Enumerator->getName());
2095 ContinuationBuilder.writeMemberType(ER);
2099 FTI = TypeTable.insertRecord(ContinuationBuilder);
2102 std::string FullName = getFullyQualifiedName(Ty);
2104 EnumRecord ER(EnumeratorCount, CO, FTI, FullName, Ty->getIdentifier(),
2105 getTypeIndex(Ty->getBaseType()));
2106 TypeIndex EnumTI = TypeTable.writeLeafType(ER);
2108 addUDTSrcLine(Ty, EnumTI);
2113 //===----------------------------------------------------------------------===//
2115 //===----------------------------------------------------------------------===//
2117 struct llvm::ClassInfo {
2119 const DIDerivedType *MemberTypeNode;
2120 uint64_t BaseOffset;
2123 using MemberList = std::vector<MemberInfo>;
2125 using MethodsList = TinyPtrVector<const DISubprogram *>;
2126 // MethodName -> MethodsList
2127 using MethodsMap = MapVector<MDString *, MethodsList>;
2130 std::vector<const DIDerivedType *> Inheritance;
2134 // Direct overloaded methods gathered by name.
2139 std::vector<const DIType *> NestedTypes;
2142 void CodeViewDebug::clear() {
2143 assert(CurFn == nullptr);
2145 FnDebugInfo.clear();
2146 FileToFilepathMap.clear();
2149 TypeIndices.clear();
2150 CompleteTypeIndices.clear();
2151 ScopeGlobals.clear();
2154 void CodeViewDebug::collectMemberInfo(ClassInfo &Info,
2155 const DIDerivedType *DDTy) {
2156 if (!DDTy->getName().empty()) {
2157 Info.Members.push_back({DDTy, 0});
2161 // An unnamed member may represent a nested struct or union. Attempt to
2162 // interpret the unnamed member as a DICompositeType possibly wrapped in
2163 // qualifier types. Add all the indirect fields to the current record if that
2164 // succeeds, and drop the member if that fails.
2165 assert((DDTy->getOffsetInBits() % 8) == 0 && "Unnamed bitfield member!");
2166 uint64_t Offset = DDTy->getOffsetInBits();
2167 const DIType *Ty = DDTy->getBaseType();
2168 bool FullyResolved = false;
2169 while (!FullyResolved) {
2170 switch (Ty->getTag()) {
2171 case dwarf::DW_TAG_const_type:
2172 case dwarf::DW_TAG_volatile_type:
2173 // FIXME: we should apply the qualifier types to the indirect fields
2174 // rather than dropping them.
2175 Ty = cast<DIDerivedType>(Ty)->getBaseType();
2178 FullyResolved = true;
2183 const DICompositeType *DCTy = dyn_cast<DICompositeType>(Ty);
2187 ClassInfo NestedInfo = collectClassInfo(DCTy);
2188 for (const ClassInfo::MemberInfo &IndirectField : NestedInfo.Members)
2189 Info.Members.push_back(
2190 {IndirectField.MemberTypeNode, IndirectField.BaseOffset + Offset});
2193 ClassInfo CodeViewDebug::collectClassInfo(const DICompositeType *Ty) {
2195 // Add elements to structure type.
2196 DINodeArray Elements = Ty->getElements();
2197 for (auto *Element : Elements) {
2198 // We assume that the frontend provides all members in source declaration
2199 // order, which is what MSVC does.
2202 if (auto *SP = dyn_cast<DISubprogram>(Element)) {
2203 Info.Methods[SP->getRawName()].push_back(SP);
2204 } else if (auto *DDTy = dyn_cast<DIDerivedType>(Element)) {
2205 if (DDTy->getTag() == dwarf::DW_TAG_member) {
2206 collectMemberInfo(Info, DDTy);
2207 } else if (DDTy->getTag() == dwarf::DW_TAG_inheritance) {
2208 Info.Inheritance.push_back(DDTy);
2209 } else if (DDTy->getTag() == dwarf::DW_TAG_pointer_type &&
2210 DDTy->getName() == "__vtbl_ptr_type") {
2211 Info.VShapeTI = getTypeIndex(DDTy);
2212 } else if (DDTy->getTag() == dwarf::DW_TAG_typedef) {
2213 Info.NestedTypes.push_back(DDTy);
2214 } else if (DDTy->getTag() == dwarf::DW_TAG_friend) {
2215 // Ignore friend members. It appears that MSVC emitted info about
2216 // friends in the past, but modern versions do not.
2218 } else if (auto *Composite = dyn_cast<DICompositeType>(Element)) {
2219 Info.NestedTypes.push_back(Composite);
2221 // Skip other unrecognized kinds of elements.
2226 static bool shouldAlwaysEmitCompleteClassType(const DICompositeType *Ty) {
2227 // This routine is used by lowerTypeClass and lowerTypeUnion to determine
2228 // if a complete type should be emitted instead of a forward reference.
2229 return Ty->getName().empty() && Ty->getIdentifier().empty() &&
2230 !Ty->isForwardDecl();
2233 TypeIndex CodeViewDebug::lowerTypeClass(const DICompositeType *Ty) {
2234 // Emit the complete type for unnamed structs. C++ classes with methods
2235 // which have a circular reference back to the class type are expected to
2236 // be named by the front-end and should not be "unnamed". C unnamed
2237 // structs should not have circular references.
2238 if (shouldAlwaysEmitCompleteClassType(Ty)) {
2239 // If this unnamed complete type is already in the process of being defined
2240 // then the description of the type is malformed and cannot be emitted
2241 // into CodeView correctly so report a fatal error.
2242 auto I = CompleteTypeIndices.find(Ty);
2243 if (I != CompleteTypeIndices.end() && I->second == TypeIndex())
2244 report_fatal_error("cannot debug circular reference to unnamed type");
2245 return getCompleteTypeIndex(Ty);
2248 // First, construct the forward decl. Don't look into Ty to compute the
2249 // forward decl options, since it might not be available in all TUs.
2250 TypeRecordKind Kind = getRecordKind(Ty);
2252 ClassOptions::ForwardReference | getCommonClassOptions(Ty);
2253 std::string FullName = getFullyQualifiedName(Ty);
2254 ClassRecord CR(Kind, 0, CO, TypeIndex(), TypeIndex(), TypeIndex(), 0,
2255 FullName, Ty->getIdentifier());
2256 TypeIndex FwdDeclTI = TypeTable.writeLeafType(CR);
2257 if (!Ty->isForwardDecl())
2258 DeferredCompleteTypes.push_back(Ty);
2262 TypeIndex CodeViewDebug::lowerCompleteTypeClass(const DICompositeType *Ty) {
2263 // Construct the field list and complete type record.
2264 TypeRecordKind Kind = getRecordKind(Ty);
2265 ClassOptions CO = getCommonClassOptions(Ty);
2268 unsigned FieldCount;
2269 bool ContainsNestedClass;
2270 std::tie(FieldTI, VShapeTI, FieldCount, ContainsNestedClass) =
2271 lowerRecordFieldList(Ty);
2273 if (ContainsNestedClass)
2274 CO |= ClassOptions::ContainsNestedClass;
2276 // MSVC appears to set this flag by searching any destructor or method with
2277 // FunctionOptions::Constructor among the emitted members. Clang AST has all
2278 // the members, however special member functions are not yet emitted into
2279 // debug information. For now checking a class's non-triviality seems enough.
2280 // FIXME: not true for a nested unnamed struct.
2281 if (isNonTrivial(Ty))
2282 CO |= ClassOptions::HasConstructorOrDestructor;
2284 std::string FullName = getFullyQualifiedName(Ty);
2286 uint64_t SizeInBytes = Ty->getSizeInBits() / 8;
2288 ClassRecord CR(Kind, FieldCount, CO, FieldTI, TypeIndex(), VShapeTI,
2289 SizeInBytes, FullName, Ty->getIdentifier());
2290 TypeIndex ClassTI = TypeTable.writeLeafType(CR);
2292 addUDTSrcLine(Ty, ClassTI);
2299 TypeIndex CodeViewDebug::lowerTypeUnion(const DICompositeType *Ty) {
2300 // Emit the complete type for unnamed unions.
2301 if (shouldAlwaysEmitCompleteClassType(Ty))
2302 return getCompleteTypeIndex(Ty);
2305 ClassOptions::ForwardReference | getCommonClassOptions(Ty);
2306 std::string FullName = getFullyQualifiedName(Ty);
2307 UnionRecord UR(0, CO, TypeIndex(), 0, FullName, Ty->getIdentifier());
2308 TypeIndex FwdDeclTI = TypeTable.writeLeafType(UR);
2309 if (!Ty->isForwardDecl())
2310 DeferredCompleteTypes.push_back(Ty);
2314 TypeIndex CodeViewDebug::lowerCompleteTypeUnion(const DICompositeType *Ty) {
2315 ClassOptions CO = ClassOptions::Sealed | getCommonClassOptions(Ty);
2317 unsigned FieldCount;
2318 bool ContainsNestedClass;
2319 std::tie(FieldTI, std::ignore, FieldCount, ContainsNestedClass) =
2320 lowerRecordFieldList(Ty);
2322 if (ContainsNestedClass)
2323 CO |= ClassOptions::ContainsNestedClass;
2325 uint64_t SizeInBytes = Ty->getSizeInBits() / 8;
2326 std::string FullName = getFullyQualifiedName(Ty);
2328 UnionRecord UR(FieldCount, CO, FieldTI, SizeInBytes, FullName,
2329 Ty->getIdentifier());
2330 TypeIndex UnionTI = TypeTable.writeLeafType(UR);
2332 addUDTSrcLine(Ty, UnionTI);
2339 std::tuple<TypeIndex, TypeIndex, unsigned, bool>
2340 CodeViewDebug::lowerRecordFieldList(const DICompositeType *Ty) {
2341 // Manually count members. MSVC appears to count everything that generates a
2342 // field list record. Each individual overload in a method overload group
2343 // contributes to this count, even though the overload group is a single field
2345 unsigned MemberCount = 0;
2346 ClassInfo Info = collectClassInfo(Ty);
2347 ContinuationRecordBuilder ContinuationBuilder;
2348 ContinuationBuilder.begin(ContinuationRecordKind::FieldList);
2350 // Create base classes.
2351 for (const DIDerivedType *I : Info.Inheritance) {
2352 if (I->getFlags() & DINode::FlagVirtual) {
2354 unsigned VBPtrOffset = I->getVBPtrOffset();
2355 // FIXME: Despite the accessor name, the offset is really in bytes.
2356 unsigned VBTableIndex = I->getOffsetInBits() / 4;
2357 auto RecordKind = (I->getFlags() & DINode::FlagIndirectVirtualBase) == DINode::FlagIndirectVirtualBase
2358 ? TypeRecordKind::IndirectVirtualBaseClass
2359 : TypeRecordKind::VirtualBaseClass;
2360 VirtualBaseClassRecord VBCR(
2361 RecordKind, translateAccessFlags(Ty->getTag(), I->getFlags()),
2362 getTypeIndex(I->getBaseType()), getVBPTypeIndex(), VBPtrOffset,
2365 ContinuationBuilder.writeMemberType(VBCR);
2368 assert(I->getOffsetInBits() % 8 == 0 &&
2369 "bases must be on byte boundaries");
2370 BaseClassRecord BCR(translateAccessFlags(Ty->getTag(), I->getFlags()),
2371 getTypeIndex(I->getBaseType()),
2372 I->getOffsetInBits() / 8);
2373 ContinuationBuilder.writeMemberType(BCR);
2379 for (ClassInfo::MemberInfo &MemberInfo : Info.Members) {
2380 const DIDerivedType *Member = MemberInfo.MemberTypeNode;
2381 TypeIndex MemberBaseType = getTypeIndex(Member->getBaseType());
2382 StringRef MemberName = Member->getName();
2383 MemberAccess Access =
2384 translateAccessFlags(Ty->getTag(), Member->getFlags());
2386 if (Member->isStaticMember()) {
2387 StaticDataMemberRecord SDMR(Access, MemberBaseType, MemberName);
2388 ContinuationBuilder.writeMemberType(SDMR);
2393 // Virtual function pointer member.
2394 if ((Member->getFlags() & DINode::FlagArtificial) &&
2395 Member->getName().startswith("_vptr$")) {
2396 VFPtrRecord VFPR(getTypeIndex(Member->getBaseType()));
2397 ContinuationBuilder.writeMemberType(VFPR);
2403 uint64_t MemberOffsetInBits =
2404 Member->getOffsetInBits() + MemberInfo.BaseOffset;
2405 if (Member->isBitField()) {
2406 uint64_t StartBitOffset = MemberOffsetInBits;
2407 if (const auto *CI =
2408 dyn_cast_or_null<ConstantInt>(Member->getStorageOffsetInBits())) {
2409 MemberOffsetInBits = CI->getZExtValue() + MemberInfo.BaseOffset;
2411 StartBitOffset -= MemberOffsetInBits;
2412 BitFieldRecord BFR(MemberBaseType, Member->getSizeInBits(),
2414 MemberBaseType = TypeTable.writeLeafType(BFR);
2416 uint64_t MemberOffsetInBytes = MemberOffsetInBits / 8;
2417 DataMemberRecord DMR(Access, MemberBaseType, MemberOffsetInBytes,
2419 ContinuationBuilder.writeMemberType(DMR);
2424 for (auto &MethodItr : Info.Methods) {
2425 StringRef Name = MethodItr.first->getString();
2427 std::vector<OneMethodRecord> Methods;
2428 for (const DISubprogram *SP : MethodItr.second) {
2429 TypeIndex MethodType = getMemberFunctionType(SP, Ty);
2430 bool Introduced = SP->getFlags() & DINode::FlagIntroducedVirtual;
2432 unsigned VFTableOffset = -1;
2434 VFTableOffset = SP->getVirtualIndex() * getPointerSizeInBytes();
2436 Methods.push_back(OneMethodRecord(
2437 MethodType, translateAccessFlags(Ty->getTag(), SP->getFlags()),
2438 translateMethodKindFlags(SP, Introduced),
2439 translateMethodOptionFlags(SP), VFTableOffset, Name));
2442 assert(!Methods.empty() && "Empty methods map entry");
2443 if (Methods.size() == 1)
2444 ContinuationBuilder.writeMemberType(Methods[0]);
2446 // FIXME: Make this use its own ContinuationBuilder so that
2447 // MethodOverloadList can be split correctly.
2448 MethodOverloadListRecord MOLR(Methods);
2449 TypeIndex MethodList = TypeTable.writeLeafType(MOLR);
2451 OverloadedMethodRecord OMR(Methods.size(), MethodList, Name);
2452 ContinuationBuilder.writeMemberType(OMR);
2456 // Create nested classes.
2457 for (const DIType *Nested : Info.NestedTypes) {
2458 NestedTypeRecord R(getTypeIndex(Nested), Nested->getName());
2459 ContinuationBuilder.writeMemberType(R);
2463 TypeIndex FieldTI = TypeTable.insertRecord(ContinuationBuilder);
2464 return std::make_tuple(FieldTI, Info.VShapeTI, MemberCount,
2465 !Info.NestedTypes.empty());
2468 TypeIndex CodeViewDebug::getVBPTypeIndex() {
2469 if (!VBPType.getIndex()) {
2470 // Make a 'const int *' type.
2471 ModifierRecord MR(TypeIndex::Int32(), ModifierOptions::Const);
2472 TypeIndex ModifiedTI = TypeTable.writeLeafType(MR);
2474 PointerKind PK = getPointerSizeInBytes() == 8 ? PointerKind::Near64
2475 : PointerKind::Near32;
2476 PointerMode PM = PointerMode::Pointer;
2477 PointerOptions PO = PointerOptions::None;
2478 PointerRecord PR(ModifiedTI, PK, PM, PO, getPointerSizeInBytes());
2479 VBPType = TypeTable.writeLeafType(PR);
2485 TypeIndex CodeViewDebug::getTypeIndex(const DIType *Ty, const DIType *ClassTy) {
2486 // The null DIType is the void type. Don't try to hash it.
2488 return TypeIndex::Void();
2490 // Check if we've already translated this type. Don't try to do a
2491 // get-or-create style insertion that caches the hash lookup across the
2492 // lowerType call. It will update the TypeIndices map.
2493 auto I = TypeIndices.find({Ty, ClassTy});
2494 if (I != TypeIndices.end())
2497 TypeLoweringScope S(*this);
2498 TypeIndex TI = lowerType(Ty, ClassTy);
2499 return recordTypeIndexForDINode(Ty, TI, ClassTy);
2503 CodeViewDebug::getTypeIndexForThisPtr(const DIDerivedType *PtrTy,
2504 const DISubroutineType *SubroutineTy) {
2505 assert(PtrTy->getTag() == dwarf::DW_TAG_pointer_type &&
2506 "this type must be a pointer type");
2508 PointerOptions Options = PointerOptions::None;
2509 if (SubroutineTy->getFlags() & DINode::DIFlags::FlagLValueReference)
2510 Options = PointerOptions::LValueRefThisPointer;
2511 else if (SubroutineTy->getFlags() & DINode::DIFlags::FlagRValueReference)
2512 Options = PointerOptions::RValueRefThisPointer;
2514 // Check if we've already translated this type. If there is no ref qualifier
2515 // on the function then we look up this pointer type with no associated class
2516 // so that the TypeIndex for the this pointer can be shared with the type
2517 // index for other pointers to this class type. If there is a ref qualifier
2518 // then we lookup the pointer using the subroutine as the parent type.
2519 auto I = TypeIndices.find({PtrTy, SubroutineTy});
2520 if (I != TypeIndices.end())
2523 TypeLoweringScope S(*this);
2524 TypeIndex TI = lowerTypePointer(PtrTy, Options);
2525 return recordTypeIndexForDINode(PtrTy, TI, SubroutineTy);
2528 TypeIndex CodeViewDebug::getTypeIndexForReferenceTo(const DIType *Ty) {
2529 PointerRecord PR(getTypeIndex(Ty),
2530 getPointerSizeInBytes() == 8 ? PointerKind::Near64
2531 : PointerKind::Near32,
2532 PointerMode::LValueReference, PointerOptions::None,
2533 Ty->getSizeInBits() / 8);
2534 return TypeTable.writeLeafType(PR);
2537 TypeIndex CodeViewDebug::getCompleteTypeIndex(const DIType *Ty) {
2538 // The null DIType is the void type. Don't try to hash it.
2540 return TypeIndex::Void();
2542 // Look through typedefs when getting the complete type index. Call
2543 // getTypeIndex on the typdef to ensure that any UDTs are accumulated and are
2544 // emitted only once.
2545 if (Ty->getTag() == dwarf::DW_TAG_typedef)
2546 (void)getTypeIndex(Ty);
2547 while (Ty->getTag() == dwarf::DW_TAG_typedef)
2548 Ty = cast<DIDerivedType>(Ty)->getBaseType();
2550 // If this is a non-record type, the complete type index is the same as the
2551 // normal type index. Just call getTypeIndex.
2552 switch (Ty->getTag()) {
2553 case dwarf::DW_TAG_class_type:
2554 case dwarf::DW_TAG_structure_type:
2555 case dwarf::DW_TAG_union_type:
2558 return getTypeIndex(Ty);
2561 const auto *CTy = cast<DICompositeType>(Ty);
2563 TypeLoweringScope S(*this);
2565 // Make sure the forward declaration is emitted first. It's unclear if this
2566 // is necessary, but MSVC does it, and we should follow suit until we can show
2568 // We only emit a forward declaration for named types.
2569 if (!CTy->getName().empty() || !CTy->getIdentifier().empty()) {
2570 TypeIndex FwdDeclTI = getTypeIndex(CTy);
2572 // Just use the forward decl if we don't have complete type info. This
2573 // might happen if the frontend is using modules and expects the complete
2574 // definition to be emitted elsewhere.
2575 if (CTy->isForwardDecl())
2579 // Check if we've already translated the complete record type.
2580 // Insert the type with a null TypeIndex to signify that the type is currently
2582 auto InsertResult = CompleteTypeIndices.insert({CTy, TypeIndex()});
2583 if (!InsertResult.second)
2584 return InsertResult.first->second;
2587 switch (CTy->getTag()) {
2588 case dwarf::DW_TAG_class_type:
2589 case dwarf::DW_TAG_structure_type:
2590 TI = lowerCompleteTypeClass(CTy);
2592 case dwarf::DW_TAG_union_type:
2593 TI = lowerCompleteTypeUnion(CTy);
2596 llvm_unreachable("not a record");
2599 // Update the type index associated with this CompositeType. This cannot
2600 // use the 'InsertResult' iterator above because it is potentially
2601 // invalidated by map insertions which can occur while lowering the class
2603 CompleteTypeIndices[CTy] = TI;
2607 /// Emit all the deferred complete record types. Try to do this in FIFO order,
2608 /// and do this until fixpoint, as each complete record type typically
2610 /// many other record types.
2611 void CodeViewDebug::emitDeferredCompleteTypes() {
2612 SmallVector<const DICompositeType *, 4> TypesToEmit;
2613 while (!DeferredCompleteTypes.empty()) {
2614 std::swap(DeferredCompleteTypes, TypesToEmit);
2615 for (const DICompositeType *RecordTy : TypesToEmit)
2616 getCompleteTypeIndex(RecordTy);
2617 TypesToEmit.clear();
2621 void CodeViewDebug::emitLocalVariableList(const FunctionInfo &FI,
2622 ArrayRef<LocalVariable> Locals) {
2623 // Get the sorted list of parameters and emit them first.
2624 SmallVector<const LocalVariable *, 6> Params;
2625 for (const LocalVariable &L : Locals)
2626 if (L.DIVar->isParameter())
2627 Params.push_back(&L);
2628 llvm::sort(Params, [](const LocalVariable *L, const LocalVariable *R) {
2629 return L->DIVar->getArg() < R->DIVar->getArg();
2631 for (const LocalVariable *L : Params)
2632 emitLocalVariable(FI, *L);
2634 // Next emit all non-parameters in the order that we found them.
2635 for (const LocalVariable &L : Locals)
2636 if (!L.DIVar->isParameter())
2637 emitLocalVariable(FI, L);
2640 void CodeViewDebug::emitLocalVariable(const FunctionInfo &FI,
2641 const LocalVariable &Var) {
2642 // LocalSym record, see SymbolRecord.h for more info.
2643 MCSymbol *LocalEnd = beginSymbolRecord(SymbolKind::S_LOCAL);
2645 LocalSymFlags Flags = LocalSymFlags::None;
2646 if (Var.DIVar->isParameter())
2647 Flags |= LocalSymFlags::IsParameter;
2648 if (Var.DefRanges.empty())
2649 Flags |= LocalSymFlags::IsOptimizedOut;
2651 OS.AddComment("TypeIndex");
2652 TypeIndex TI = Var.UseReferenceType
2653 ? getTypeIndexForReferenceTo(Var.DIVar->getType())
2654 : getCompleteTypeIndex(Var.DIVar->getType());
2655 OS.emitInt32(TI.getIndex());
2656 OS.AddComment("Flags");
2657 OS.emitInt16(static_cast<uint16_t>(Flags));
2658 // Truncate the name so we won't overflow the record length field.
2659 emitNullTerminatedSymbolName(OS, Var.DIVar->getName());
2660 endSymbolRecord(LocalEnd);
2662 // Calculate the on disk prefix of the appropriate def range record. The
2663 // records and on disk formats are described in SymbolRecords.h. BytePrefix
2664 // should be big enough to hold all forms without memory allocation.
2665 SmallString<20> BytePrefix;
2666 for (const LocalVarDefRange &DefRange : Var.DefRanges) {
2668 if (DefRange.InMemory) {
2669 int Offset = DefRange.DataOffset;
2670 unsigned Reg = DefRange.CVRegister;
2672 // 32-bit x86 call sequences often use PUSH instructions, which disrupt
2673 // ESP-relative offsets. Use the virtual frame pointer, VFRAME or $T0,
2674 // instead. In frames without stack realignment, $T0 will be the CFA.
2675 if (RegisterId(Reg) == RegisterId::ESP) {
2676 Reg = unsigned(RegisterId::VFRAME);
2677 Offset += FI.OffsetAdjustment;
2680 // If we can use the chosen frame pointer for the frame and this isn't a
2681 // sliced aggregate, use the smaller S_DEFRANGE_FRAMEPOINTER_REL record.
2682 // Otherwise, use S_DEFRANGE_REGISTER_REL.
2683 EncodedFramePtrReg EncFP = encodeFramePtrReg(RegisterId(Reg), TheCPU);
2684 if (!DefRange.IsSubfield && EncFP != EncodedFramePtrReg::None &&
2685 (bool(Flags & LocalSymFlags::IsParameter)
2686 ? (EncFP == FI.EncodedParamFramePtrReg)
2687 : (EncFP == FI.EncodedLocalFramePtrReg))) {
2688 DefRangeFramePointerRelHeader DRHdr;
2689 DRHdr.Offset = Offset;
2690 OS.emitCVDefRangeDirective(DefRange.Ranges, DRHdr);
2692 uint16_t RegRelFlags = 0;
2693 if (DefRange.IsSubfield) {
2694 RegRelFlags = DefRangeRegisterRelSym::IsSubfieldFlag |
2695 (DefRange.StructOffset
2696 << DefRangeRegisterRelSym::OffsetInParentShift);
2698 DefRangeRegisterRelHeader DRHdr;
2699 DRHdr.Register = Reg;
2700 DRHdr.Flags = RegRelFlags;
2701 DRHdr.BasePointerOffset = Offset;
2702 OS.emitCVDefRangeDirective(DefRange.Ranges, DRHdr);
2705 assert(DefRange.DataOffset == 0 && "unexpected offset into register");
2706 if (DefRange.IsSubfield) {
2707 DefRangeSubfieldRegisterHeader DRHdr;
2708 DRHdr.Register = DefRange.CVRegister;
2709 DRHdr.MayHaveNoName = 0;
2710 DRHdr.OffsetInParent = DefRange.StructOffset;
2711 OS.emitCVDefRangeDirective(DefRange.Ranges, DRHdr);
2713 DefRangeRegisterHeader DRHdr;
2714 DRHdr.Register = DefRange.CVRegister;
2715 DRHdr.MayHaveNoName = 0;
2716 OS.emitCVDefRangeDirective(DefRange.Ranges, DRHdr);
2722 void CodeViewDebug::emitLexicalBlockList(ArrayRef<LexicalBlock *> Blocks,
2723 const FunctionInfo& FI) {
2724 for (LexicalBlock *Block : Blocks)
2725 emitLexicalBlock(*Block, FI);
2728 /// Emit an S_BLOCK32 and S_END record pair delimiting the contents of a
2729 /// lexical block scope.
2730 void CodeViewDebug::emitLexicalBlock(const LexicalBlock &Block,
2731 const FunctionInfo& FI) {
2732 MCSymbol *RecordEnd = beginSymbolRecord(SymbolKind::S_BLOCK32);
2733 OS.AddComment("PtrParent");
2734 OS.emitInt32(0); // PtrParent
2735 OS.AddComment("PtrEnd");
2736 OS.emitInt32(0); // PtrEnd
2737 OS.AddComment("Code size");
2738 OS.emitAbsoluteSymbolDiff(Block.End, Block.Begin, 4); // Code Size
2739 OS.AddComment("Function section relative address");
2740 OS.EmitCOFFSecRel32(Block.Begin, /*Offset=*/0); // Func Offset
2741 OS.AddComment("Function section index");
2742 OS.EmitCOFFSectionIndex(FI.Begin); // Func Symbol
2743 OS.AddComment("Lexical block name");
2744 emitNullTerminatedSymbolName(OS, Block.Name); // Name
2745 endSymbolRecord(RecordEnd);
2747 // Emit variables local to this lexical block.
2748 emitLocalVariableList(FI, Block.Locals);
2749 emitGlobalVariableList(Block.Globals);
2751 // Emit lexical blocks contained within this block.
2752 emitLexicalBlockList(Block.Children, FI);
2754 // Close the lexical block scope.
2755 emitEndSymbolRecord(SymbolKind::S_END);
2758 /// Convenience routine for collecting lexical block information for a list
2759 /// of lexical scopes.
2760 void CodeViewDebug::collectLexicalBlockInfo(
2761 SmallVectorImpl<LexicalScope *> &Scopes,
2762 SmallVectorImpl<LexicalBlock *> &Blocks,
2763 SmallVectorImpl<LocalVariable> &Locals,
2764 SmallVectorImpl<CVGlobalVariable> &Globals) {
2765 for (LexicalScope *Scope : Scopes)
2766 collectLexicalBlockInfo(*Scope, Blocks, Locals, Globals);
2769 /// Populate the lexical blocks and local variable lists of the parent with
2770 /// information about the specified lexical scope.
2771 void CodeViewDebug::collectLexicalBlockInfo(
2772 LexicalScope &Scope,
2773 SmallVectorImpl<LexicalBlock *> &ParentBlocks,
2774 SmallVectorImpl<LocalVariable> &ParentLocals,
2775 SmallVectorImpl<CVGlobalVariable> &ParentGlobals) {
2776 if (Scope.isAbstractScope())
2779 // Gather information about the lexical scope including local variables,
2780 // global variables, and address ranges.
2781 bool IgnoreScope = false;
2782 auto LI = ScopeVariables.find(&Scope);
2783 SmallVectorImpl<LocalVariable> *Locals =
2784 LI != ScopeVariables.end() ? &LI->second : nullptr;
2785 auto GI = ScopeGlobals.find(Scope.getScopeNode());
2786 SmallVectorImpl<CVGlobalVariable> *Globals =
2787 GI != ScopeGlobals.end() ? GI->second.get() : nullptr;
2788 const DILexicalBlock *DILB = dyn_cast<DILexicalBlock>(Scope.getScopeNode());
2789 const SmallVectorImpl<InsnRange> &Ranges = Scope.getRanges();
2791 // Ignore lexical scopes which do not contain variables.
2792 if (!Locals && !Globals)
2795 // Ignore lexical scopes which are not lexical blocks.
2799 // Ignore scopes which have too many address ranges to represent in the
2800 // current CodeView format or do not have a valid address range.
2802 // For lexical scopes with multiple address ranges you may be tempted to
2803 // construct a single range covering every instruction where the block is
2804 // live and everything in between. Unfortunately, Visual Studio only
2805 // displays variables from the first matching lexical block scope. If the
2806 // first lexical block contains exception handling code or cold code which
2807 // is moved to the bottom of the routine creating a single range covering
2808 // nearly the entire routine, then it will hide all other lexical blocks
2809 // and the variables they contain.
2810 if (Ranges.size() != 1 || !getLabelAfterInsn(Ranges.front().second))
2814 // This scope can be safely ignored and eliminating it will reduce the
2815 // size of the debug information. Be sure to collect any variable and scope
2816 // information from the this scope or any of its children and collapse them
2817 // into the parent scope.
2819 ParentLocals.append(Locals->begin(), Locals->end());
2821 ParentGlobals.append(Globals->begin(), Globals->end());
2822 collectLexicalBlockInfo(Scope.getChildren(),
2829 // Create a new CodeView lexical block for this lexical scope. If we've
2830 // seen this DILexicalBlock before then the scope tree is malformed and
2831 // we can handle this gracefully by not processing it a second time.
2832 auto BlockInsertion = CurFn->LexicalBlocks.insert({DILB, LexicalBlock()});
2833 if (!BlockInsertion.second)
2836 // Create a lexical block containing the variables and collect the the
2837 // lexical block information for the children.
2838 const InsnRange &Range = Ranges.front();
2839 assert(Range.first && Range.second);
2840 LexicalBlock &Block = BlockInsertion.first->second;
2841 Block.Begin = getLabelBeforeInsn(Range.first);
2842 Block.End = getLabelAfterInsn(Range.second);
2843 assert(Block.Begin && "missing label for scope begin");
2844 assert(Block.End && "missing label for scope end");
2845 Block.Name = DILB->getName();
2847 Block.Locals = std::move(*Locals);
2849 Block.Globals = std::move(*Globals);
2850 ParentBlocks.push_back(&Block);
2851 collectLexicalBlockInfo(Scope.getChildren(),
2857 void CodeViewDebug::endFunctionImpl(const MachineFunction *MF) {
2858 const Function &GV = MF->getFunction();
2859 assert(FnDebugInfo.count(&GV));
2860 assert(CurFn == FnDebugInfo[&GV].get());
2862 collectVariableInfo(GV.getSubprogram());
2864 // Build the lexical block structure to emit for this routine.
2865 if (LexicalScope *CFS = LScopes.getCurrentFunctionScope())
2866 collectLexicalBlockInfo(*CFS,
2871 // Clear the scope and variable information from the map which will not be
2872 // valid after we have finished processing this routine. This also prepares
2873 // the map for the subsequent routine.
2874 ScopeVariables.clear();
2876 // Don't emit anything if we don't have any line tables.
2877 // Thunks are compiler-generated and probably won't have source correlation.
2878 if (!CurFn->HaveLineInfo && !GV.getSubprogram()->isThunk()) {
2879 FnDebugInfo.erase(&GV);
2884 // Find heap alloc sites and add to list.
2885 for (const auto &MBB : *MF) {
2886 for (const auto &MI : MBB) {
2887 if (MDNode *MD = MI.getHeapAllocMarker()) {
2888 CurFn->HeapAllocSites.push_back(std::make_tuple(getLabelBeforeInsn(&MI),
2889 getLabelAfterInsn(&MI),
2890 dyn_cast<DIType>(MD)));
2895 CurFn->Annotations = MF->getCodeViewAnnotations();
2897 CurFn->End = Asm->getFunctionEnd();
2902 // Usable locations are valid with non-zero line numbers. A line number of zero
2903 // corresponds to optimized code that doesn't have a distinct source location.
2904 // In this case, we try to use the previous or next source location depending on
2906 static bool isUsableDebugLoc(DebugLoc DL) {
2907 return DL && DL.getLine() != 0;
2910 void CodeViewDebug::beginInstruction(const MachineInstr *MI) {
2911 DebugHandlerBase::beginInstruction(MI);
2913 // Ignore DBG_VALUE and DBG_LABEL locations and function prologue.
2914 if (!Asm || !CurFn || MI->isDebugInstr() ||
2915 MI->getFlag(MachineInstr::FrameSetup))
2918 // If the first instruction of a new MBB has no location, find the first
2919 // instruction with a location and use that.
2920 DebugLoc DL = MI->getDebugLoc();
2921 if (!isUsableDebugLoc(DL) && MI->getParent() != PrevInstBB) {
2922 for (const auto &NextMI : *MI->getParent()) {
2923 if (NextMI.isDebugInstr())
2925 DL = NextMI.getDebugLoc();
2926 if (isUsableDebugLoc(DL))
2929 // FIXME: Handle the case where the BB has no valid locations. This would
2930 // probably require doing a real dataflow analysis.
2932 PrevInstBB = MI->getParent();
2934 // If we still don't have a debug location, don't record a location.
2935 if (!isUsableDebugLoc(DL))
2938 maybeRecordLocation(DL, Asm->MF);
2941 MCSymbol *CodeViewDebug::beginCVSubsection(DebugSubsectionKind Kind) {
2942 MCSymbol *BeginLabel = MMI->getContext().createTempSymbol(),
2943 *EndLabel = MMI->getContext().createTempSymbol();
2944 OS.emitInt32(unsigned(Kind));
2945 OS.AddComment("Subsection size");
2946 OS.emitAbsoluteSymbolDiff(EndLabel, BeginLabel, 4);
2947 OS.emitLabel(BeginLabel);
2951 void CodeViewDebug::endCVSubsection(MCSymbol *EndLabel) {
2952 OS.emitLabel(EndLabel);
2953 // Every subsection must be aligned to a 4-byte boundary.
2954 OS.emitValueToAlignment(4);
2957 static StringRef getSymbolName(SymbolKind SymKind) {
2958 for (const EnumEntry<SymbolKind> &EE : getSymbolTypeNames())
2959 if (EE.Value == SymKind)
2964 MCSymbol *CodeViewDebug::beginSymbolRecord(SymbolKind SymKind) {
2965 MCSymbol *BeginLabel = MMI->getContext().createTempSymbol(),
2966 *EndLabel = MMI->getContext().createTempSymbol();
2967 OS.AddComment("Record length");
2968 OS.emitAbsoluteSymbolDiff(EndLabel, BeginLabel, 2);
2969 OS.emitLabel(BeginLabel);
2970 if (OS.isVerboseAsm())
2971 OS.AddComment("Record kind: " + getSymbolName(SymKind));
2972 OS.emitInt16(unsigned(SymKind));
2976 void CodeViewDebug::endSymbolRecord(MCSymbol *SymEnd) {
2977 // MSVC does not pad out symbol records to four bytes, but LLVM does to avoid
2978 // an extra copy of every symbol record in LLD. This increases object file
2979 // size by less than 1% in the clang build, and is compatible with the Visual
2981 OS.emitValueToAlignment(4);
2982 OS.emitLabel(SymEnd);
2985 void CodeViewDebug::emitEndSymbolRecord(SymbolKind EndKind) {
2986 OS.AddComment("Record length");
2988 if (OS.isVerboseAsm())
2989 OS.AddComment("Record kind: " + getSymbolName(EndKind));
2990 OS.emitInt16(uint16_t(EndKind)); // Record Kind
2993 void CodeViewDebug::emitDebugInfoForUDTs(
2994 const std::vector<std::pair<std::string, const DIType *>> &UDTs) {
2996 size_t OriginalSize = UDTs.size();
2998 for (const auto &UDT : UDTs) {
2999 const DIType *T = UDT.second;
3000 assert(shouldEmitUdt(T));
3001 MCSymbol *UDTRecordEnd = beginSymbolRecord(SymbolKind::S_UDT);
3002 OS.AddComment("Type");
3003 OS.emitInt32(getCompleteTypeIndex(T).getIndex());
3004 assert(OriginalSize == UDTs.size() &&
3005 "getCompleteTypeIndex found new UDTs!");
3006 emitNullTerminatedSymbolName(OS, UDT.first);
3007 endSymbolRecord(UDTRecordEnd);
3011 void CodeViewDebug::collectGlobalVariableInfo() {
3012 DenseMap<const DIGlobalVariableExpression *, const GlobalVariable *>
3014 for (const GlobalVariable &GV : MMI->getModule()->globals()) {
3015 SmallVector<DIGlobalVariableExpression *, 1> GVEs;
3016 GV.getDebugInfo(GVEs);
3017 for (const auto *GVE : GVEs)
3018 GlobalMap[GVE] = &GV;
3021 NamedMDNode *CUs = MMI->getModule()->getNamedMetadata("llvm.dbg.cu");
3022 for (const MDNode *Node : CUs->operands()) {
3023 const auto *CU = cast<DICompileUnit>(Node);
3024 for (const auto *GVE : CU->getGlobalVariables()) {
3025 const DIGlobalVariable *DIGV = GVE->getVariable();
3026 const DIExpression *DIE = GVE->getExpression();
3028 // Emit constant global variables in a global symbol section.
3029 if (GlobalMap.count(GVE) == 0 && DIE->isConstant()) {
3030 CVGlobalVariable CVGV = {DIGV, DIE};
3031 GlobalVariables.emplace_back(std::move(CVGV));
3034 const auto *GV = GlobalMap.lookup(GVE);
3035 if (!GV || GV->isDeclarationForLinker())
3038 DIScope *Scope = DIGV->getScope();
3039 SmallVector<CVGlobalVariable, 1> *VariableList;
3040 if (Scope && isa<DILocalScope>(Scope)) {
3041 // Locate a global variable list for this scope, creating one if
3043 auto Insertion = ScopeGlobals.insert(
3044 {Scope, std::unique_ptr<GlobalVariableList>()});
3045 if (Insertion.second)
3046 Insertion.first->second = std::make_unique<GlobalVariableList>();
3047 VariableList = Insertion.first->second.get();
3048 } else if (GV->hasComdat())
3049 // Emit this global variable into a COMDAT section.
3050 VariableList = &ComdatVariables;
3052 // Emit this global variable in a single global symbol section.
3053 VariableList = &GlobalVariables;
3054 CVGlobalVariable CVGV = {DIGV, GV};
3055 VariableList->emplace_back(std::move(CVGV));
3060 void CodeViewDebug::emitDebugInfoForGlobals() {
3061 // First, emit all globals that are not in a comdat in a single symbol
3062 // substream. MSVC doesn't like it if the substream is empty, so only open
3063 // it if we have at least one global to emit.
3064 switchToDebugSectionForSymbol(nullptr);
3065 if (!GlobalVariables.empty()) {
3066 OS.AddComment("Symbol subsection for globals");
3067 MCSymbol *EndLabel = beginCVSubsection(DebugSubsectionKind::Symbols);
3068 emitGlobalVariableList(GlobalVariables);
3069 endCVSubsection(EndLabel);
3072 // Second, emit each global that is in a comdat into its own .debug$S
3073 // section along with its own symbol substream.
3074 for (const CVGlobalVariable &CVGV : ComdatVariables) {
3075 const GlobalVariable *GV = CVGV.GVInfo.get<const GlobalVariable *>();
3076 MCSymbol *GVSym = Asm->getSymbol(GV);
3077 OS.AddComment("Symbol subsection for " +
3078 Twine(GlobalValue::dropLLVMManglingEscape(GV->getName())));
3079 switchToDebugSectionForSymbol(GVSym);
3080 MCSymbol *EndLabel = beginCVSubsection(DebugSubsectionKind::Symbols);
3081 // FIXME: emitDebugInfoForGlobal() doesn't handle DIExpressions.
3082 emitDebugInfoForGlobal(CVGV);
3083 endCVSubsection(EndLabel);
3087 void CodeViewDebug::emitDebugInfoForRetainedTypes() {
3088 NamedMDNode *CUs = MMI->getModule()->getNamedMetadata("llvm.dbg.cu");
3089 for (const MDNode *Node : CUs->operands()) {
3090 for (auto *Ty : cast<DICompileUnit>(Node)->getRetainedTypes()) {
3091 if (DIType *RT = dyn_cast<DIType>(Ty)) {
3093 // FIXME: Add to global/local DTU list.
3099 // Emit each global variable in the specified array.
3100 void CodeViewDebug::emitGlobalVariableList(ArrayRef<CVGlobalVariable> Globals) {
3101 for (const CVGlobalVariable &CVGV : Globals) {
3102 // FIXME: emitDebugInfoForGlobal() doesn't handle DIExpressions.
3103 emitDebugInfoForGlobal(CVGV);
3107 void CodeViewDebug::emitDebugInfoForGlobal(const CVGlobalVariable &CVGV) {
3108 const DIGlobalVariable *DIGV = CVGV.DIGV;
3110 const DIScope *Scope = DIGV->getScope();
3111 // For static data members, get the scope from the declaration.
3112 if (const auto *MemberDecl = dyn_cast_or_null<DIDerivedType>(
3113 DIGV->getRawStaticDataMemberDeclaration()))
3114 Scope = MemberDecl->getScope();
3115 std::string QualifiedName = getFullyQualifiedName(Scope, DIGV->getName());
3117 if (const GlobalVariable *GV =
3118 CVGV.GVInfo.dyn_cast<const GlobalVariable *>()) {
3119 // DataSym record, see SymbolRecord.h for more info. Thread local data
3120 // happens to have the same format as global data.
3121 MCSymbol *GVSym = Asm->getSymbol(GV);
3122 SymbolKind DataSym = GV->isThreadLocal()
3123 ? (DIGV->isLocalToUnit() ? SymbolKind::S_LTHREAD32
3124 : SymbolKind::S_GTHREAD32)
3125 : (DIGV->isLocalToUnit() ? SymbolKind::S_LDATA32
3126 : SymbolKind::S_GDATA32);
3127 MCSymbol *DataEnd = beginSymbolRecord(DataSym);
3128 OS.AddComment("Type");
3129 OS.emitInt32(getCompleteTypeIndex(DIGV->getType()).getIndex());
3130 OS.AddComment("DataOffset");
3131 OS.EmitCOFFSecRel32(GVSym, /*Offset=*/0);
3132 OS.AddComment("Segment");
3133 OS.EmitCOFFSectionIndex(GVSym);
3134 OS.AddComment("Name");
3135 const unsigned LengthOfDataRecord = 12;
3136 emitNullTerminatedSymbolName(OS, QualifiedName, LengthOfDataRecord);
3137 endSymbolRecord(DataEnd);
3139 const DIExpression *DIE = CVGV.GVInfo.get<const DIExpression *>();
3140 assert(DIE->isConstant() &&
3141 "Global constant variables must contain a constant expression.");
3142 uint64_t Val = DIE->getElement(1);
3144 MCSymbol *SConstantEnd = beginSymbolRecord(SymbolKind::S_CONSTANT);
3145 OS.AddComment("Type");
3146 OS.emitInt32(getTypeIndex(DIGV->getType()).getIndex());
3147 OS.AddComment("Value");
3149 // Encoded integers shouldn't need more than 10 bytes.
3151 BinaryStreamWriter Writer(data, llvm::support::endianness::little);
3152 CodeViewRecordIO IO(Writer);
3153 cantFail(IO.mapEncodedInteger(Val));
3154 StringRef SRef((char *)data, Writer.getOffset());
3155 OS.emitBinaryData(SRef);
3157 OS.AddComment("Name");
3158 emitNullTerminatedSymbolName(OS, QualifiedName);
3159 endSymbolRecord(SConstantEnd);