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Diffstat (limited to 'contrib/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp')
| -rw-r--r-- | contrib/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp | 2255 |
1 files changed, 2255 insertions, 0 deletions
diff --git a/contrib/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp b/contrib/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp new file mode 100644 index 000000000000..786b11618d75 --- /dev/null +++ b/contrib/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp @@ -0,0 +1,2255 @@ +//===-- llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp --*- C++ -*--===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file contains support for writing Microsoft CodeView debug info. +// +//===----------------------------------------------------------------------===// + +#include "CodeViewDebug.h" +#include "llvm/ADT/TinyPtrVector.h" +#include "llvm/DebugInfo/CodeView/CVTypeDumper.h" +#include "llvm/DebugInfo/CodeView/CVTypeVisitor.h" +#include "llvm/DebugInfo/CodeView/CodeView.h" +#include "llvm/DebugInfo/CodeView/Line.h" +#include "llvm/DebugInfo/CodeView/ModuleDebugInlineeLinesFragment.h" +#include "llvm/DebugInfo/CodeView/SymbolRecord.h" +#include "llvm/DebugInfo/CodeView/TypeDatabase.h" +#include "llvm/DebugInfo/CodeView/TypeDumpVisitor.h" +#include "llvm/DebugInfo/CodeView/TypeIndex.h" +#include "llvm/DebugInfo/CodeView/TypeRecord.h" +#include "llvm/DebugInfo/CodeView/TypeVisitorCallbacks.h" +#include "llvm/IR/Constants.h" +#include "llvm/MC/MCAsmInfo.h" +#include "llvm/MC/MCExpr.h" +#include "llvm/MC/MCSectionCOFF.h" +#include "llvm/MC/MCSymbol.h" +#include "llvm/Support/BinaryByteStream.h" +#include "llvm/Support/BinaryStreamReader.h" +#include "llvm/Support/COFF.h" +#include "llvm/Support/ScopedPrinter.h" +#include "llvm/Target/TargetFrameLowering.h" +#include "llvm/Target/TargetRegisterInfo.h" +#include "llvm/Target/TargetSubtargetInfo.h" + +using namespace llvm; +using namespace llvm::codeview; + +CodeViewDebug::CodeViewDebug(AsmPrinter *AP) + : DebugHandlerBase(AP), OS(*Asm->OutStreamer), Allocator(), + TypeTable(Allocator), CurFn(nullptr) { + // If module doesn't have named metadata anchors or COFF debug section + // is not available, skip any debug info related stuff. + if (!MMI->getModule()->getNamedMetadata("llvm.dbg.cu") || + !AP->getObjFileLowering().getCOFFDebugSymbolsSection()) { + Asm = nullptr; + return; + } + + // Tell MMI that we have debug info. + MMI->setDebugInfoAvailability(true); +} + +StringRef CodeViewDebug::getFullFilepath(const DIFile *File) { + std::string &Filepath = FileToFilepathMap[File]; + if (!Filepath.empty()) + return Filepath; + + StringRef Dir = File->getDirectory(), Filename = File->getFilename(); + + // Clang emits directory and relative filename info into the IR, but CodeView + // operates on full paths. We could change Clang to emit full paths too, but + // that would increase the IR size and probably not needed for other users. + // For now, just concatenate and canonicalize the path here. + if (Filename.find(':') == 1) + Filepath = Filename; + else + Filepath = (Dir + "\\" + Filename).str(); + + // Canonicalize the path. We have to do it textually because we may no longer + // have access the file in the filesystem. + // First, replace all slashes with backslashes. + std::replace(Filepath.begin(), Filepath.end(), '/', '\\'); + + // Remove all "\.\" with "\". + size_t Cursor = 0; + while ((Cursor = Filepath.find("\\.\\", Cursor)) != std::string::npos) + Filepath.erase(Cursor, 2); + + // Replace all "\XXX\..\" with "\". Don't try too hard though as the original + // path should be well-formatted, e.g. start with a drive letter, etc. + Cursor = 0; + while ((Cursor = Filepath.find("\\..\\", Cursor)) != std::string::npos) { + // Something's wrong if the path starts with "\..\", abort. + if (Cursor == 0) + break; + + size_t PrevSlash = Filepath.rfind('\\', Cursor - 1); + if (PrevSlash == std::string::npos) + // Something's wrong, abort. + break; + + Filepath.erase(PrevSlash, Cursor + 3 - PrevSlash); + // The next ".." might be following the one we've just erased. + Cursor = PrevSlash; + } + + // Remove all duplicate backslashes. + Cursor = 0; + while ((Cursor = Filepath.find("\\\\", Cursor)) != std::string::npos) + Filepath.erase(Cursor, 1); + + return Filepath; +} + +unsigned CodeViewDebug::maybeRecordFile(const DIFile *F) { + unsigned NextId = FileIdMap.size() + 1; + auto Insertion = FileIdMap.insert(std::make_pair(F, NextId)); + if (Insertion.second) { + // We have to compute the full filepath and emit a .cv_file directive. + StringRef FullPath = getFullFilepath(F); + bool Success = OS.EmitCVFileDirective(NextId, FullPath); + (void)Success; + assert(Success && ".cv_file directive failed"); + } + return Insertion.first->second; +} + +CodeViewDebug::InlineSite & +CodeViewDebug::getInlineSite(const DILocation *InlinedAt, + const DISubprogram *Inlinee) { + auto SiteInsertion = CurFn->InlineSites.insert({InlinedAt, InlineSite()}); + InlineSite *Site = &SiteInsertion.first->second; + if (SiteInsertion.second) { + unsigned ParentFuncId = CurFn->FuncId; + if (const DILocation *OuterIA = InlinedAt->getInlinedAt()) + ParentFuncId = + getInlineSite(OuterIA, InlinedAt->getScope()->getSubprogram()) + .SiteFuncId; + + Site->SiteFuncId = NextFuncId++; + OS.EmitCVInlineSiteIdDirective( + Site->SiteFuncId, ParentFuncId, maybeRecordFile(InlinedAt->getFile()), + InlinedAt->getLine(), InlinedAt->getColumn(), SMLoc()); + Site->Inlinee = Inlinee; + InlinedSubprograms.insert(Inlinee); + getFuncIdForSubprogram(Inlinee); + } + return *Site; +} + +static StringRef getPrettyScopeName(const DIScope *Scope) { + StringRef ScopeName = Scope->getName(); + if (!ScopeName.empty()) + return ScopeName; + + switch (Scope->getTag()) { + case dwarf::DW_TAG_enumeration_type: + case dwarf::DW_TAG_class_type: + case dwarf::DW_TAG_structure_type: + case dwarf::DW_TAG_union_type: + return "<unnamed-tag>"; + case dwarf::DW_TAG_namespace: + return "`anonymous namespace'"; + } + + return StringRef(); +} + +static const DISubprogram *getQualifiedNameComponents( + const DIScope *Scope, SmallVectorImpl<StringRef> &QualifiedNameComponents) { + const DISubprogram *ClosestSubprogram = nullptr; + while (Scope != nullptr) { + if (ClosestSubprogram == nullptr) + ClosestSubprogram = dyn_cast<DISubprogram>(Scope); + StringRef ScopeName = getPrettyScopeName(Scope); + if (!ScopeName.empty()) + QualifiedNameComponents.push_back(ScopeName); + Scope = Scope->getScope().resolve(); + } + return ClosestSubprogram; +} + +static std::string getQualifiedName(ArrayRef<StringRef> QualifiedNameComponents, + StringRef TypeName) { + std::string FullyQualifiedName; + for (StringRef QualifiedNameComponent : reverse(QualifiedNameComponents)) { + FullyQualifiedName.append(QualifiedNameComponent); + FullyQualifiedName.append("::"); + } + FullyQualifiedName.append(TypeName); + return FullyQualifiedName; +} + +static std::string getFullyQualifiedName(const DIScope *Scope, StringRef Name) { + SmallVector<StringRef, 5> QualifiedNameComponents; + getQualifiedNameComponents(Scope, QualifiedNameComponents); + return getQualifiedName(QualifiedNameComponents, Name); +} + +struct CodeViewDebug::TypeLoweringScope { + TypeLoweringScope(CodeViewDebug &CVD) : CVD(CVD) { ++CVD.TypeEmissionLevel; } + ~TypeLoweringScope() { + // Don't decrement TypeEmissionLevel until after emitting deferred types, so + // inner TypeLoweringScopes don't attempt to emit deferred types. + if (CVD.TypeEmissionLevel == 1) + CVD.emitDeferredCompleteTypes(); + --CVD.TypeEmissionLevel; + } + CodeViewDebug &CVD; +}; + +static std::string getFullyQualifiedName(const DIScope *Ty) { + const DIScope *Scope = Ty->getScope().resolve(); + return getFullyQualifiedName(Scope, getPrettyScopeName(Ty)); +} + +TypeIndex CodeViewDebug::getScopeIndex(const DIScope *Scope) { + // No scope means global scope and that uses the zero index. + if (!Scope || isa<DIFile>(Scope)) + return TypeIndex(); + + assert(!isa<DIType>(Scope) && "shouldn't make a namespace scope for a type"); + + // Check if we've already translated this scope. + auto I = TypeIndices.find({Scope, nullptr}); + if (I != TypeIndices.end()) + return I->second; + + // Build the fully qualified name of the scope. + std::string ScopeName = getFullyQualifiedName(Scope); + StringIdRecord SID(TypeIndex(), ScopeName); + auto TI = TypeTable.writeKnownType(SID); + return recordTypeIndexForDINode(Scope, TI); +} + +TypeIndex CodeViewDebug::getFuncIdForSubprogram(const DISubprogram *SP) { + assert(SP); + + // Check if we've already translated this subprogram. + auto I = TypeIndices.find({SP, nullptr}); + if (I != TypeIndices.end()) + return I->second; + + // The display name includes function template arguments. Drop them to match + // MSVC. + StringRef DisplayName = SP->getName().split('<').first; + + const DIScope *Scope = SP->getScope().resolve(); + TypeIndex TI; + if (const auto *Class = dyn_cast_or_null<DICompositeType>(Scope)) { + // If the scope is a DICompositeType, then this must be a method. Member + // function types take some special handling, and require access to the + // subprogram. + TypeIndex ClassType = getTypeIndex(Class); + MemberFuncIdRecord MFuncId(ClassType, getMemberFunctionType(SP, Class), + DisplayName); + TI = TypeTable.writeKnownType(MFuncId); + } else { + // Otherwise, this must be a free function. + TypeIndex ParentScope = getScopeIndex(Scope); + FuncIdRecord FuncId(ParentScope, getTypeIndex(SP->getType()), DisplayName); + TI = TypeTable.writeKnownType(FuncId); + } + + return recordTypeIndexForDINode(SP, TI); +} + +TypeIndex CodeViewDebug::getMemberFunctionType(const DISubprogram *SP, + const DICompositeType *Class) { + // Always use the method declaration as the key for the function type. The + // method declaration contains the this adjustment. + if (SP->getDeclaration()) + SP = SP->getDeclaration(); + assert(!SP->getDeclaration() && "should use declaration as key"); + + // Key the MemberFunctionRecord into the map as {SP, Class}. It won't collide + // with the MemberFuncIdRecord, which is keyed in as {SP, nullptr}. + auto I = TypeIndices.find({SP, Class}); + if (I != TypeIndices.end()) + return I->second; + + // Make sure complete type info for the class is emitted *after* the member + // function type, as the complete class type is likely to reference this + // member function type. + TypeLoweringScope S(*this); + TypeIndex TI = + lowerTypeMemberFunction(SP->getType(), Class, SP->getThisAdjustment()); + return recordTypeIndexForDINode(SP, TI, Class); +} + +TypeIndex CodeViewDebug::recordTypeIndexForDINode(const DINode *Node, + TypeIndex TI, + const DIType *ClassTy) { + auto InsertResult = TypeIndices.insert({{Node, ClassTy}, TI}); + (void)InsertResult; + assert(InsertResult.second && "DINode was already assigned a type index"); + return TI; +} + +unsigned CodeViewDebug::getPointerSizeInBytes() { + return MMI->getModule()->getDataLayout().getPointerSizeInBits() / 8; +} + +void CodeViewDebug::recordLocalVariable(LocalVariable &&Var, + const DILocation *InlinedAt) { + if (InlinedAt) { + // This variable was inlined. Associate it with the InlineSite. + const DISubprogram *Inlinee = Var.DIVar->getScope()->getSubprogram(); + InlineSite &Site = getInlineSite(InlinedAt, Inlinee); + Site.InlinedLocals.emplace_back(Var); + } else { + // This variable goes in the main ProcSym. + CurFn->Locals.emplace_back(Var); + } +} + +static void addLocIfNotPresent(SmallVectorImpl<const DILocation *> &Locs, + const DILocation *Loc) { + auto B = Locs.begin(), E = Locs.end(); + if (std::find(B, E, Loc) == E) + Locs.push_back(Loc); +} + +void CodeViewDebug::maybeRecordLocation(const DebugLoc &DL, + const MachineFunction *MF) { + // Skip this instruction if it has the same location as the previous one. + if (DL == CurFn->LastLoc) + return; + + const DIScope *Scope = DL.get()->getScope(); + if (!Scope) + return; + + // Skip this line if it is longer than the maximum we can record. + LineInfo LI(DL.getLine(), DL.getLine(), /*IsStatement=*/true); + if (LI.getStartLine() != DL.getLine() || LI.isAlwaysStepInto() || + LI.isNeverStepInto()) + return; + + ColumnInfo CI(DL.getCol(), /*EndColumn=*/0); + if (CI.getStartColumn() != DL.getCol()) + return; + + if (!CurFn->HaveLineInfo) + CurFn->HaveLineInfo = true; + unsigned FileId = 0; + if (CurFn->LastLoc.get() && CurFn->LastLoc->getFile() == DL->getFile()) + FileId = CurFn->LastFileId; + else + FileId = CurFn->LastFileId = maybeRecordFile(DL->getFile()); + CurFn->LastLoc = DL; + + unsigned FuncId = CurFn->FuncId; + if (const DILocation *SiteLoc = DL->getInlinedAt()) { + const DILocation *Loc = DL.get(); + + // If this location was actually inlined from somewhere else, give it the ID + // of the inline call site. + FuncId = + getInlineSite(SiteLoc, Loc->getScope()->getSubprogram()).SiteFuncId; + + // Ensure we have links in the tree of inline call sites. + bool FirstLoc = true; + while ((SiteLoc = Loc->getInlinedAt())) { + InlineSite &Site = + getInlineSite(SiteLoc, Loc->getScope()->getSubprogram()); + if (!FirstLoc) + addLocIfNotPresent(Site.ChildSites, Loc); + FirstLoc = false; + Loc = SiteLoc; + } + addLocIfNotPresent(CurFn->ChildSites, Loc); + } + + OS.EmitCVLocDirective(FuncId, FileId, DL.getLine(), DL.getCol(), + /*PrologueEnd=*/false, /*IsStmt=*/false, + DL->getFilename(), SMLoc()); +} + +void CodeViewDebug::emitCodeViewMagicVersion() { + OS.EmitValueToAlignment(4); + OS.AddComment("Debug section magic"); + OS.EmitIntValue(COFF::DEBUG_SECTION_MAGIC, 4); +} + +void CodeViewDebug::endModule() { + if (!Asm || !MMI->hasDebugInfo()) + return; + + assert(Asm != nullptr); + + // The COFF .debug$S section consists of several subsections, each starting + // with a 4-byte control code (e.g. 0xF1, 0xF2, etc) and then a 4-byte length + // of the payload followed by the payload itself. The subsections are 4-byte + // aligned. + + // Use the generic .debug$S section, and make a subsection for all the inlined + // subprograms. + switchToDebugSectionForSymbol(nullptr); + + MCSymbol *CompilerInfo = beginCVSubsection(ModuleDebugFragmentKind::Symbols); + emitCompilerInformation(); + endCVSubsection(CompilerInfo); + + emitInlineeLinesSubsection(); + + // Emit per-function debug information. + for (auto &P : FnDebugInfo) + if (!P.first->isDeclarationForLinker()) + emitDebugInfoForFunction(P.first, P.second); + + // Emit global variable debug information. + setCurrentSubprogram(nullptr); + emitDebugInfoForGlobals(); + + // Emit retained types. + emitDebugInfoForRetainedTypes(); + + // Switch back to the generic .debug$S section after potentially processing + // comdat symbol sections. + switchToDebugSectionForSymbol(nullptr); + + // Emit UDT records for any types used by global variables. + if (!GlobalUDTs.empty()) { + MCSymbol *SymbolsEnd = beginCVSubsection(ModuleDebugFragmentKind::Symbols); + emitDebugInfoForUDTs(GlobalUDTs); + endCVSubsection(SymbolsEnd); + } + + // This subsection holds a file index to offset in string table table. + OS.AddComment("File index to string table offset subsection"); + OS.EmitCVFileChecksumsDirective(); + + // This subsection holds the string table. + OS.AddComment("String table"); + OS.EmitCVStringTableDirective(); + + // Emit type information last, so that any types we translate while emitting + // function info are included. + emitTypeInformation(); + + clear(); +} + +static void emitNullTerminatedSymbolName(MCStreamer &OS, StringRef S) { + // The maximum CV record length is 0xFF00. Most of the strings we emit appear + // after a fixed length portion of the record. The fixed length portion should + // always be less than 0xF00 (3840) bytes, so truncate the string so that the + // overall record size is less than the maximum allowed. + unsigned MaxFixedRecordLength = 0xF00; + SmallString<32> NullTerminatedString( + S.take_front(MaxRecordLength - MaxFixedRecordLength - 1)); + NullTerminatedString.push_back('\0'); + OS.EmitBytes(NullTerminatedString); +} + +void CodeViewDebug::emitTypeInformation() { + // Do nothing if we have no debug info or if no non-trivial types were emitted + // to TypeTable during codegen. + NamedMDNode *CU_Nodes = MMI->getModule()->getNamedMetadata("llvm.dbg.cu"); + if (!CU_Nodes) + return; + if (TypeTable.empty()) + return; + + // Start the .debug$T section with 0x4. + OS.SwitchSection(Asm->getObjFileLowering().getCOFFDebugTypesSection()); + emitCodeViewMagicVersion(); + + SmallString<8> CommentPrefix; + if (OS.isVerboseAsm()) { + CommentPrefix += '\t'; + CommentPrefix += Asm->MAI->getCommentString(); + CommentPrefix += ' '; + } + + TypeDatabase TypeDB; + CVTypeDumper CVTD(TypeDB); + TypeTable.ForEachRecord([&](TypeIndex Index, ArrayRef<uint8_t> Record) { + if (OS.isVerboseAsm()) { + // Emit a block comment describing the type record for readability. + SmallString<512> CommentBlock; + raw_svector_ostream CommentOS(CommentBlock); + ScopedPrinter SP(CommentOS); + SP.setPrefix(CommentPrefix); + TypeDumpVisitor TDV(TypeDB, &SP, false); + Error E = CVTD.dump(Record, TDV); + if (E) { + logAllUnhandledErrors(std::move(E), errs(), "error: "); + llvm_unreachable("produced malformed type record"); + } + // emitRawComment will insert its own tab and comment string before + // the first line, so strip off our first one. It also prints its own + // newline. + OS.emitRawComment( + CommentOS.str().drop_front(CommentPrefix.size() - 1).rtrim()); + } else { +#ifndef NDEBUG + // Assert that the type data is valid even if we aren't dumping + // comments. The MSVC linker doesn't do much type record validation, + // so the first link of an invalid type record can succeed while + // subsequent links will fail with LNK1285. + BinaryByteStream Stream(Record, llvm::support::little); + CVTypeArray Types; + BinaryStreamReader Reader(Stream); + Error E = Reader.readArray(Types, Reader.getLength()); + if (!E) { + TypeVisitorCallbacks C; + E = CVTypeVisitor(C).visitTypeStream(Types); + } + if (E) { + logAllUnhandledErrors(std::move(E), errs(), "error: "); + llvm_unreachable("produced malformed type record"); + } +#endif + } + StringRef S(reinterpret_cast<const char *>(Record.data()), Record.size()); + OS.EmitBinaryData(S); + }); +} + +namespace { + +static SourceLanguage MapDWLangToCVLang(unsigned DWLang) { + switch (DWLang) { + case dwarf::DW_LANG_C: + case dwarf::DW_LANG_C89: + case dwarf::DW_LANG_C99: + case dwarf::DW_LANG_C11: + case dwarf::DW_LANG_ObjC: + return SourceLanguage::C; + case dwarf::DW_LANG_C_plus_plus: + case dwarf::DW_LANG_C_plus_plus_03: + case dwarf::DW_LANG_C_plus_plus_11: + case dwarf::DW_LANG_C_plus_plus_14: + return SourceLanguage::Cpp; + case dwarf::DW_LANG_Fortran77: + case dwarf::DW_LANG_Fortran90: + case dwarf::DW_LANG_Fortran03: + case dwarf::DW_LANG_Fortran08: + return SourceLanguage::Fortran; + case dwarf::DW_LANG_Pascal83: + return SourceLanguage::Pascal; + case dwarf::DW_LANG_Cobol74: + case dwarf::DW_LANG_Cobol85: + return SourceLanguage::Cobol; + case dwarf::DW_LANG_Java: + return SourceLanguage::Java; + default: + // There's no CodeView representation for this language, and CV doesn't + // have an "unknown" option for the language field, so we'll use MASM, + // as it's very low level. + return SourceLanguage::Masm; + } +} + +struct Version { + int Part[4]; +}; + +// Takes a StringRef like "clang 4.0.0.0 (other nonsense 123)" and parses out +// the version number. +static Version parseVersion(StringRef Name) { + Version V = {{0}}; + int N = 0; + for (const char C : Name) { + if (isdigit(C)) { + V.Part[N] *= 10; + V.Part[N] += C - '0'; + } else if (C == '.') { + ++N; + if (N >= 4) + return V; + } else if (N > 0) + return V; + } + return V; +} + +static CPUType mapArchToCVCPUType(Triple::ArchType Type) { + switch (Type) { + case Triple::ArchType::x86: + return CPUType::Pentium3; + case Triple::ArchType::x86_64: + return CPUType::X64; + case Triple::ArchType::thumb: + return CPUType::Thumb; + default: + report_fatal_error("target architecture doesn't map to a CodeView " + "CPUType"); + } +} + +} // anonymous namespace + +void CodeViewDebug::emitCompilerInformation() { + MCContext &Context = MMI->getContext(); + MCSymbol *CompilerBegin = Context.createTempSymbol(), + *CompilerEnd = Context.createTempSymbol(); + OS.AddComment("Record length"); + OS.emitAbsoluteSymbolDiff(CompilerEnd, CompilerBegin, 2); + OS.EmitLabel(CompilerBegin); + OS.AddComment("Record kind: S_COMPILE3"); + OS.EmitIntValue(SymbolKind::S_COMPILE3, 2); + uint32_t Flags = 0; + + NamedMDNode *CUs = MMI->getModule()->getNamedMetadata("llvm.dbg.cu"); + const MDNode *Node = *CUs->operands().begin(); + const auto *CU = cast<DICompileUnit>(Node); + + // The low byte of the flags indicates the source language. + Flags = MapDWLangToCVLang(CU->getSourceLanguage()); + // TODO: Figure out which other flags need to be set. + + OS.AddComment("Flags and language"); + OS.EmitIntValue(Flags, 4); + + OS.AddComment("CPUType"); + CPUType CPU = + mapArchToCVCPUType(Triple(MMI->getModule()->getTargetTriple()).getArch()); + OS.EmitIntValue(static_cast<uint64_t>(CPU), 2); + + StringRef CompilerVersion = CU->getProducer(); + Version FrontVer = parseVersion(CompilerVersion); + OS.AddComment("Frontend version"); + for (int N = 0; N < 4; ++N) + OS.EmitIntValue(FrontVer.Part[N], 2); + + // Some Microsoft tools, like Binscope, expect a backend version number of at + // least 8.something, so we'll coerce the LLVM version into a form that + // guarantees it'll be big enough without really lying about the version. + int Major = 1000 * LLVM_VERSION_MAJOR + + 10 * LLVM_VERSION_MINOR + + LLVM_VERSION_PATCH; + // Clamp it for builds that use unusually large version numbers. + Major = std::min<int>(Major, std::numeric_limits<uint16_t>::max()); + Version BackVer = {{ Major, 0, 0, 0 }}; + OS.AddComment("Backend version"); + for (int N = 0; N < 4; ++N) + OS.EmitIntValue(BackVer.Part[N], 2); + + OS.AddComment("Null-terminated compiler version string"); + emitNullTerminatedSymbolName(OS, CompilerVersion); + + OS.EmitLabel(CompilerEnd); +} + +void CodeViewDebug::emitInlineeLinesSubsection() { + if (InlinedSubprograms.empty()) + return; + + OS.AddComment("Inlinee lines subsection"); + MCSymbol *InlineEnd = + beginCVSubsection(ModuleDebugFragmentKind::InlineeLines); + + // We don't provide any extra file info. + // FIXME: Find out if debuggers use this info. + OS.AddComment("Inlinee lines signature"); + OS.EmitIntValue(unsigned(InlineeLinesSignature::Normal), 4); + + for (const DISubprogram *SP : InlinedSubprograms) { + assert(TypeIndices.count({SP, nullptr})); + TypeIndex InlineeIdx = TypeIndices[{SP, nullptr}]; + + OS.AddBlankLine(); + unsigned FileId = maybeRecordFile(SP->getFile()); + OS.AddComment("Inlined function " + SP->getName() + " starts at " + + SP->getFilename() + Twine(':') + Twine(SP->getLine())); + OS.AddBlankLine(); + // The filechecksum table uses 8 byte entries for now, and file ids start at + // 1. + unsigned FileOffset = (FileId - 1) * 8; + OS.AddComment("Type index of inlined function"); + OS.EmitIntValue(InlineeIdx.getIndex(), 4); + OS.AddComment("Offset into filechecksum table"); + OS.EmitIntValue(FileOffset, 4); + OS.AddComment("Starting line number"); + OS.EmitIntValue(SP->getLine(), 4); + } + + endCVSubsection(InlineEnd); +} + +void CodeViewDebug::emitInlinedCallSite(const FunctionInfo &FI, + const DILocation *InlinedAt, + const InlineSite &Site) { + MCSymbol *InlineBegin = MMI->getContext().createTempSymbol(), + *InlineEnd = MMI->getContext().createTempSymbol(); + + assert(TypeIndices.count({Site.Inlinee, nullptr})); + TypeIndex InlineeIdx = TypeIndices[{Site.Inlinee, nullptr}]; + + // SymbolRecord + OS.AddComment("Record length"); + OS.emitAbsoluteSymbolDiff(InlineEnd, InlineBegin, 2); // RecordLength + OS.EmitLabel(InlineBegin); + OS.AddComment("Record kind: S_INLINESITE"); + OS.EmitIntValue(SymbolKind::S_INLINESITE, 2); // RecordKind + + OS.AddComment("PtrParent"); + OS.EmitIntValue(0, 4); + OS.AddComment("PtrEnd"); + OS.EmitIntValue(0, 4); + OS.AddComment("Inlinee type index"); + OS.EmitIntValue(InlineeIdx.getIndex(), 4); + + unsigned FileId = maybeRecordFile(Site.Inlinee->getFile()); + unsigned StartLineNum = Site.Inlinee->getLine(); + + OS.EmitCVInlineLinetableDirective(Site.SiteFuncId, FileId, StartLineNum, + FI.Begin, FI.End); + + OS.EmitLabel(InlineEnd); + + emitLocalVariableList(Site.InlinedLocals); + + // Recurse on child inlined call sites before closing the scope. + for (const DILocation *ChildSite : Site.ChildSites) { + auto I = FI.InlineSites.find(ChildSite); + assert(I != FI.InlineSites.end() && + "child site not in function inline site map"); + emitInlinedCallSite(FI, ChildSite, I->second); + } + + // Close the scope. + OS.AddComment("Record length"); + OS.EmitIntValue(2, 2); // RecordLength + OS.AddComment("Record kind: S_INLINESITE_END"); + OS.EmitIntValue(SymbolKind::S_INLINESITE_END, 2); // RecordKind +} + +void CodeViewDebug::switchToDebugSectionForSymbol(const MCSymbol *GVSym) { + // If we have a symbol, it may be in a section that is COMDAT. If so, find the + // comdat key. A section may be comdat because of -ffunction-sections or + // because it is comdat in the IR. + MCSectionCOFF *GVSec = + GVSym ? dyn_cast<MCSectionCOFF>(&GVSym->getSection()) : nullptr; + const MCSymbol *KeySym = GVSec ? GVSec->getCOMDATSymbol() : nullptr; + + MCSectionCOFF *DebugSec = cast<MCSectionCOFF>( + Asm->getObjFileLowering().getCOFFDebugSymbolsSection()); + DebugSec = OS.getContext().getAssociativeCOFFSection(DebugSec, KeySym); + + OS.SwitchSection(DebugSec); + + // Emit the magic version number if this is the first time we've switched to + // this section. + if (ComdatDebugSections.insert(DebugSec).second) + emitCodeViewMagicVersion(); +} + +void CodeViewDebug::emitDebugInfoForFunction(const Function *GV, + FunctionInfo &FI) { + // For each function there is a separate subsection + // which holds the PC to file:line table. + const MCSymbol *Fn = Asm->getSymbol(GV); + assert(Fn); + + // Switch to the to a comdat section, if appropriate. + switchToDebugSectionForSymbol(Fn); + + std::string FuncName; + auto *SP = GV->getSubprogram(); + assert(SP); + setCurrentSubprogram(SP); + + // If we have a display name, build the fully qualified name by walking the + // chain of scopes. + if (!SP->getName().empty()) + FuncName = + getFullyQualifiedName(SP->getScope().resolve(), SP->getName()); + + // If our DISubprogram name is empty, use the mangled name. + if (FuncName.empty()) + FuncName = GlobalValue::getRealLinkageName(GV->getName()); + + // Emit a symbol subsection, required by VS2012+ to find function boundaries. + OS.AddComment("Symbol subsection for " + Twine(FuncName)); + MCSymbol *SymbolsEnd = beginCVSubsection(ModuleDebugFragmentKind::Symbols); + { + MCSymbol *ProcRecordBegin = MMI->getContext().createTempSymbol(), + *ProcRecordEnd = MMI->getContext().createTempSymbol(); + OS.AddComment("Record length"); + OS.emitAbsoluteSymbolDiff(ProcRecordEnd, ProcRecordBegin, 2); + OS.EmitLabel(ProcRecordBegin); + + if (GV->hasLocalLinkage()) { + OS.AddComment("Record kind: S_LPROC32_ID"); + OS.EmitIntValue(unsigned(SymbolKind::S_LPROC32_ID), 2); + } else { + OS.AddComment("Record kind: S_GPROC32_ID"); + OS.EmitIntValue(unsigned(SymbolKind::S_GPROC32_ID), 2); + } + + // These fields are filled in by tools like CVPACK which run after the fact. + OS.AddComment("PtrParent"); + OS.EmitIntValue(0, 4); + OS.AddComment("PtrEnd"); + OS.EmitIntValue(0, 4); + OS.AddComment("PtrNext"); + OS.EmitIntValue(0, 4); + // This is the important bit that tells the debugger where the function + // code is located and what's its size: + OS.AddComment("Code size"); + OS.emitAbsoluteSymbolDiff(FI.End, Fn, 4); + OS.AddComment("Offset after prologue"); + OS.EmitIntValue(0, 4); + OS.AddComment("Offset before epilogue"); + OS.EmitIntValue(0, 4); + OS.AddComment("Function type index"); + OS.EmitIntValue(getFuncIdForSubprogram(GV->getSubprogram()).getIndex(), 4); + OS.AddComment("Function section relative address"); + OS.EmitCOFFSecRel32(Fn, /*Offset=*/0); + OS.AddComment("Function section index"); + OS.EmitCOFFSectionIndex(Fn); + OS.AddComment("Flags"); + OS.EmitIntValue(0, 1); + // Emit the function display name as a null-terminated string. + OS.AddComment("Function name"); + // Truncate the name so we won't overflow the record length field. + emitNullTerminatedSymbolName(OS, FuncName); + OS.EmitLabel(ProcRecordEnd); + + emitLocalVariableList(FI.Locals); + + // Emit inlined call site information. Only emit functions inlined directly + // into the parent function. We'll emit the other sites recursively as part + // of their parent inline site. + for (const DILocation *InlinedAt : FI.ChildSites) { + auto I = FI.InlineSites.find(InlinedAt); + assert(I != FI.InlineSites.end() && + "child site not in function inline site map"); + emitInlinedCallSite(FI, InlinedAt, I->second); + } + + if (SP != nullptr) + emitDebugInfoForUDTs(LocalUDTs); + + // We're done with this function. + OS.AddComment("Record length"); + OS.EmitIntValue(0x0002, 2); + OS.AddComment("Record kind: S_PROC_ID_END"); + OS.EmitIntValue(unsigned(SymbolKind::S_PROC_ID_END), 2); + } + endCVSubsection(SymbolsEnd); + + // We have an assembler directive that takes care of the whole line table. + OS.EmitCVLinetableDirective(FI.FuncId, Fn, FI.End); +} + +CodeViewDebug::LocalVarDefRange +CodeViewDebug::createDefRangeMem(uint16_t CVRegister, int Offset) { + LocalVarDefRange DR; + DR.InMemory = -1; + DR.DataOffset = Offset; + assert(DR.DataOffset == Offset && "truncation"); + DR.IsSubfield = 0; + DR.StructOffset = 0; + DR.CVRegister = CVRegister; + return DR; +} + +CodeViewDebug::LocalVarDefRange +CodeViewDebug::createDefRangeGeneral(uint16_t CVRegister, bool InMemory, + int Offset, bool IsSubfield, + uint16_t StructOffset) { + LocalVarDefRange DR; + DR.InMemory = InMemory; + DR.DataOffset = Offset; + DR.IsSubfield = IsSubfield; + DR.StructOffset = StructOffset; + DR.CVRegister = CVRegister; + return DR; +} + +void CodeViewDebug::collectVariableInfoFromMFTable( + DenseSet<InlinedVariable> &Processed) { + const MachineFunction &MF = *Asm->MF; + const TargetSubtargetInfo &TSI = MF.getSubtarget(); + const TargetFrameLowering *TFI = TSI.getFrameLowering(); + const TargetRegisterInfo *TRI = TSI.getRegisterInfo(); + + for (const MachineFunction::VariableDbgInfo &VI : MF.getVariableDbgInfo()) { + if (!VI.Var) + continue; + assert(VI.Var->isValidLocationForIntrinsic(VI.Loc) && + "Expected inlined-at fields to agree"); + + Processed.insert(InlinedVariable(VI.Var, VI.Loc->getInlinedAt())); + LexicalScope *Scope = LScopes.findLexicalScope(VI.Loc); + + // If variable scope is not found then skip this variable. + if (!Scope) + continue; + + // Get the frame register used and the offset. + unsigned FrameReg = 0; + int FrameOffset = TFI->getFrameIndexReference(*Asm->MF, VI.Slot, FrameReg); + uint16_t CVReg = TRI->getCodeViewRegNum(FrameReg); + + // Calculate the label ranges. + LocalVarDefRange DefRange = createDefRangeMem(CVReg, FrameOffset); + for (const InsnRange &Range : Scope->getRanges()) { + const MCSymbol *Begin = getLabelBeforeInsn(Range.first); + const MCSymbol *End = getLabelAfterInsn(Range.second); + End = End ? End : Asm->getFunctionEnd(); + DefRange.Ranges.emplace_back(Begin, End); + } + + LocalVariable Var; + Var.DIVar = VI.Var; + Var.DefRanges.emplace_back(std::move(DefRange)); + recordLocalVariable(std::move(Var), VI.Loc->getInlinedAt()); + } +} + +void CodeViewDebug::collectVariableInfo(const DISubprogram *SP) { + DenseSet<InlinedVariable> Processed; + // Grab the variable info that was squirreled away in the MMI side-table. + collectVariableInfoFromMFTable(Processed); + + const TargetRegisterInfo *TRI = Asm->MF->getSubtarget().getRegisterInfo(); + + for (const auto &I : DbgValues) { + InlinedVariable IV = I.first; + if (Processed.count(IV)) + continue; + const DILocalVariable *DIVar = IV.first; + const DILocation *InlinedAt = IV.second; + + // Instruction ranges, specifying where IV is accessible. + const auto &Ranges = I.second; + + LexicalScope *Scope = nullptr; + if (InlinedAt) + Scope = LScopes.findInlinedScope(DIVar->getScope(), InlinedAt); + else + Scope = LScopes.findLexicalScope(DIVar->getScope()); + // If variable scope is not found then skip this variable. + if (!Scope) + continue; + + LocalVariable Var; + Var.DIVar = DIVar; + + // Calculate the definition ranges. + for (auto I = Ranges.begin(), E = Ranges.end(); I != E; ++I) { + const InsnRange &Range = *I; + const MachineInstr *DVInst = Range.first; + assert(DVInst->isDebugValue() && "Invalid History entry"); + const DIExpression *DIExpr = DVInst->getDebugExpression(); + bool IsSubfield = false; + unsigned StructOffset = 0; + + // Handle fragments. + auto Fragment = DIExpr->getFragmentInfo(); + if (Fragment) { + IsSubfield = true; + StructOffset = Fragment->OffsetInBits / 8; + } else if (DIExpr->getNumElements() > 0) { + continue; // Ignore unrecognized exprs. + } + + // Bail if operand 0 is not a valid register. This means the variable is a + // simple constant, or is described by a complex expression. + // FIXME: Find a way to represent constant variables, since they are + // relatively common. + unsigned Reg = + DVInst->getOperand(0).isReg() ? DVInst->getOperand(0).getReg() : 0; + if (Reg == 0) + continue; + + // Handle the two cases we can handle: indirect in memory and in register. + unsigned CVReg = TRI->getCodeViewRegNum(Reg); + bool InMemory = DVInst->getOperand(1).isImm(); + int Offset = InMemory ? DVInst->getOperand(1).getImm() : 0; + { + LocalVarDefRange DR; + DR.CVRegister = CVReg; + DR.InMemory = InMemory; + DR.DataOffset = Offset; + DR.IsSubfield = IsSubfield; + DR.StructOffset = StructOffset; + + if (Var.DefRanges.empty() || + Var.DefRanges.back().isDifferentLocation(DR)) { + Var.DefRanges.emplace_back(std::move(DR)); + } + } + + // Compute the label range. + const MCSymbol *Begin = getLabelBeforeInsn(Range.first); + const MCSymbol *End = getLabelAfterInsn(Range.second); + if (!End) { + // This range is valid until the next overlapping bitpiece. In the + // common case, ranges will not be bitpieces, so they will overlap. + auto J = std::next(I); + while (J != E && + !fragmentsOverlap(DIExpr, J->first->getDebugExpression())) + ++J; + if (J != E) + End = getLabelBeforeInsn(J->first); + else + End = Asm->getFunctionEnd(); + } + + // If the last range end is our begin, just extend the last range. + // Otherwise make a new range. + SmallVectorImpl<std::pair<const MCSymbol *, const MCSymbol *>> &Ranges = + Var.DefRanges.back().Ranges; + if (!Ranges.empty() && Ranges.back().second == Begin) + Ranges.back().second = End; + else + Ranges.emplace_back(Begin, End); + + // FIXME: Do more range combining. + } + + recordLocalVariable(std::move(Var), InlinedAt); + } +} + +void CodeViewDebug::beginFunctionImpl(const MachineFunction *MF) { + const Function *GV = MF->getFunction(); + assert(FnDebugInfo.count(GV) == false); + CurFn = &FnDebugInfo[GV]; + CurFn->FuncId = NextFuncId++; + CurFn->Begin = Asm->getFunctionBegin(); + + OS.EmitCVFuncIdDirective(CurFn->FuncId); + + // Find the end of the function prolog. First known non-DBG_VALUE and + // non-frame setup location marks the beginning of the function body. + // FIXME: is there a simpler a way to do this? Can we just search + // for the first instruction of the function, not the last of the prolog? + DebugLoc PrologEndLoc; + bool EmptyPrologue = true; + for (const auto &MBB : *MF) { + for (const auto &MI : MBB) { + if (!MI.isDebugValue() && !MI.getFlag(MachineInstr::FrameSetup) && + MI.getDebugLoc()) { + PrologEndLoc = MI.getDebugLoc(); + break; + } else if (!MI.isDebugValue()) { + EmptyPrologue = false; + } + } + } + + // Record beginning of function if we have a non-empty prologue. + if (PrologEndLoc && !EmptyPrologue) { + DebugLoc FnStartDL = PrologEndLoc.getFnDebugLoc(); + maybeRecordLocation(FnStartDL, MF); + } +} + +void CodeViewDebug::addToUDTs(const DIType *Ty, TypeIndex TI) { + // Don't record empty UDTs. + if (Ty->getName().empty()) + return; + + SmallVector<StringRef, 5> QualifiedNameComponents; + const DISubprogram *ClosestSubprogram = getQualifiedNameComponents( + Ty->getScope().resolve(), QualifiedNameComponents); + + std::string FullyQualifiedName = + getQualifiedName(QualifiedNameComponents, getPrettyScopeName(Ty)); + + if (ClosestSubprogram == nullptr) + GlobalUDTs.emplace_back(std::move(FullyQualifiedName), TI); + else if (ClosestSubprogram == CurrentSubprogram) + LocalUDTs.emplace_back(std::move(FullyQualifiedName), TI); + + // TODO: What if the ClosestSubprogram is neither null or the current + // subprogram? Currently, the UDT just gets dropped on the floor. + // + // The current behavior is not desirable. To get maximal fidelity, we would + // need to perform all type translation before beginning emission of .debug$S + // and then make LocalUDTs a member of FunctionInfo +} + +TypeIndex CodeViewDebug::lowerType(const DIType *Ty, const DIType *ClassTy) { + // Generic dispatch for lowering an unknown type. + switch (Ty->getTag()) { + case dwarf::DW_TAG_array_type: + return lowerTypeArray(cast<DICompositeType>(Ty)); + case dwarf::DW_TAG_typedef: + return lowerTypeAlias(cast<DIDerivedType>(Ty)); + case dwarf::DW_TAG_base_type: + return lowerTypeBasic(cast<DIBasicType>(Ty)); + case dwarf::DW_TAG_pointer_type: + if (cast<DIDerivedType>(Ty)->getName() == "__vtbl_ptr_type") + return lowerTypeVFTableShape(cast<DIDerivedType>(Ty)); + LLVM_FALLTHROUGH; + case dwarf::DW_TAG_reference_type: + case dwarf::DW_TAG_rvalue_reference_type: + return lowerTypePointer(cast<DIDerivedType>(Ty)); + case dwarf::DW_TAG_ptr_to_member_type: + return lowerTypeMemberPointer(cast<DIDerivedType>(Ty)); + case dwarf::DW_TAG_const_type: + case dwarf::DW_TAG_volatile_type: + // TODO: add support for DW_TAG_atomic_type here + return lowerTypeModifier(cast<DIDerivedType>(Ty)); + case dwarf::DW_TAG_subroutine_type: + if (ClassTy) { + // The member function type of a member function pointer has no + // ThisAdjustment. + return lowerTypeMemberFunction(cast<DISubroutineType>(Ty), ClassTy, + /*ThisAdjustment=*/0); + } + return lowerTypeFunction(cast<DISubroutineType>(Ty)); + case dwarf::DW_TAG_enumeration_type: + return lowerTypeEnum(cast<DICompositeType>(Ty)); + case dwarf::DW_TAG_class_type: + case dwarf::DW_TAG_structure_type: + return lowerTypeClass(cast<DICompositeType>(Ty)); + case dwarf::DW_TAG_union_type: + return lowerTypeUnion(cast<DICompositeType>(Ty)); + default: + // Use the null type index. + return TypeIndex(); + } +} + +TypeIndex CodeViewDebug::lowerTypeAlias(const DIDerivedType *Ty) { + DITypeRef UnderlyingTypeRef = Ty->getBaseType(); + TypeIndex UnderlyingTypeIndex = getTypeIndex(UnderlyingTypeRef); + StringRef TypeName = Ty->getName(); + + addToUDTs(Ty, UnderlyingTypeIndex); + + if (UnderlyingTypeIndex == TypeIndex(SimpleTypeKind::Int32Long) && + TypeName == "HRESULT") + return TypeIndex(SimpleTypeKind::HResult); + if (UnderlyingTypeIndex == TypeIndex(SimpleTypeKind::UInt16Short) && + TypeName == "wchar_t") + return TypeIndex(SimpleTypeKind::WideCharacter); + + return UnderlyingTypeIndex; +} + +TypeIndex CodeViewDebug::lowerTypeArray(const DICompositeType *Ty) { + DITypeRef ElementTypeRef = Ty->getBaseType(); + TypeIndex ElementTypeIndex = getTypeIndex(ElementTypeRef); + // IndexType is size_t, which depends on the bitness of the target. + TypeIndex IndexType = Asm->TM.getPointerSize() == 8 + ? TypeIndex(SimpleTypeKind::UInt64Quad) + : TypeIndex(SimpleTypeKind::UInt32Long); + + uint64_t ElementSize = getBaseTypeSize(ElementTypeRef) / 8; + + // Add subranges to array type. + DINodeArray Elements = Ty->getElements(); + for (int i = Elements.size() - 1; i >= 0; --i) { + const DINode *Element = Elements[i]; + assert(Element->getTag() == dwarf::DW_TAG_subrange_type); + + const DISubrange *Subrange = cast<DISubrange>(Element); + assert(Subrange->getLowerBound() == 0 && + "codeview doesn't support subranges with lower bounds"); + int64_t Count = Subrange->getCount(); + + // Variable Length Array (VLA) has Count equal to '-1'. + // Replace with Count '1', assume it is the minimum VLA length. + // FIXME: Make front-end support VLA subrange and emit LF_DIMVARLU. + if (Count == -1) + Count = 1; + + // Update the element size and element type index for subsequent subranges. + ElementSize *= Count; + + // If this is the outermost array, use the size from the array. It will be + // more accurate if we had a VLA or an incomplete element type size. + uint64_t ArraySize = + (i == 0 && ElementSize == 0) ? Ty->getSizeInBits() / 8 : ElementSize; + + StringRef Name = (i == 0) ? Ty->getName() : ""; + ArrayRecord AR(ElementTypeIndex, IndexType, ArraySize, Name); + ElementTypeIndex = TypeTable.writeKnownType(AR); + } + + return ElementTypeIndex; +} + +TypeIndex CodeViewDebug::lowerTypeBasic(const DIBasicType *Ty) { + TypeIndex Index; + dwarf::TypeKind Kind; + uint32_t ByteSize; + + Kind = static_cast<dwarf::TypeKind>(Ty->getEncoding()); + ByteSize = Ty->getSizeInBits() / 8; + + SimpleTypeKind STK = SimpleTypeKind::None; + switch (Kind) { + case dwarf::DW_ATE_address: + // FIXME: Translate + break; + case dwarf::DW_ATE_boolean: + switch (ByteSize) { + case 1: STK = SimpleTypeKind::Boolean8; break; + case 2: STK = SimpleTypeKind::Boolean16; break; + case 4: STK = SimpleTypeKind::Boolean32; break; + case 8: STK = SimpleTypeKind::Boolean64; break; + case 16: STK = SimpleTypeKind::Boolean128; break; + } + break; + case dwarf::DW_ATE_complex_float: + switch (ByteSize) { + case 2: STK = SimpleTypeKind::Complex16; break; + case 4: STK = SimpleTypeKind::Complex32; break; + case 8: STK = SimpleTypeKind::Complex64; break; + case 10: STK = SimpleTypeKind::Complex80; break; + case 16: STK = SimpleTypeKind::Complex128; break; + } + break; + case dwarf::DW_ATE_float: + switch (ByteSize) { + case 2: STK = SimpleTypeKind::Float16; break; + case 4: STK = SimpleTypeKind::Float32; break; + case 6: STK = SimpleTypeKind::Float48; break; + case 8: STK = SimpleTypeKind::Float64; break; + case 10: STK = SimpleTypeKind::Float80; break; + case 16: STK = SimpleTypeKind::Float128; break; + } + break; + case dwarf::DW_ATE_signed: + switch (ByteSize) { + case 1: STK = SimpleTypeKind::SignedCharacter; break; + case 2: STK = SimpleTypeKind::Int16Short; break; + case 4: STK = SimpleTypeKind::Int32; break; + case 8: STK = SimpleTypeKind::Int64Quad; break; + case 16: STK = SimpleTypeKind::Int128Oct; break; + } + break; + case dwarf::DW_ATE_unsigned: + switch (ByteSize) { + case 1: STK = SimpleTypeKind::UnsignedCharacter; break; + case 2: STK = SimpleTypeKind::UInt16Short; break; + case 4: STK = SimpleTypeKind::UInt32; break; + case 8: STK = SimpleTypeKind::UInt64Quad; break; + case 16: STK = SimpleTypeKind::UInt128Oct; break; + } + break; + case dwarf::DW_ATE_UTF: + switch (ByteSize) { + case 2: STK = SimpleTypeKind::Character16; break; + case 4: STK = SimpleTypeKind::Character32; break; + } + break; + case dwarf::DW_ATE_signed_char: + if (ByteSize == 1) + STK = SimpleTypeKind::SignedCharacter; + break; + case dwarf::DW_ATE_unsigned_char: + if (ByteSize == 1) + STK = SimpleTypeKind::UnsignedCharacter; + break; + default: + break; + } + + // Apply some fixups based on the source-level type name. + if (STK == SimpleTypeKind::Int32 && Ty->getName() == "long int") + STK = SimpleTypeKind::Int32Long; + if (STK == SimpleTypeKind::UInt32 && Ty->getName() == "long unsigned int") + STK = SimpleTypeKind::UInt32Long; + if (STK == SimpleTypeKind::UInt16Short && + (Ty->getName() == "wchar_t" || Ty->getName() == "__wchar_t")) + STK = SimpleTypeKind::WideCharacter; + if ((STK == SimpleTypeKind::SignedCharacter || + STK == SimpleTypeKind::UnsignedCharacter) && + Ty->getName() == "char") + STK = SimpleTypeKind::NarrowCharacter; + + return TypeIndex(STK); +} + +TypeIndex CodeViewDebug::lowerTypePointer(const DIDerivedType *Ty) { + TypeIndex PointeeTI = getTypeIndex(Ty->getBaseType()); + + // Pointers to simple types can use SimpleTypeMode, rather than having a + // dedicated pointer type record. + if (PointeeTI.isSimple() && + PointeeTI.getSimpleMode() == SimpleTypeMode::Direct && + Ty->getTag() == dwarf::DW_TAG_pointer_type) { + SimpleTypeMode Mode = Ty->getSizeInBits() == 64 + ? SimpleTypeMode::NearPointer64 + : SimpleTypeMode::NearPointer32; + return TypeIndex(PointeeTI.getSimpleKind(), Mode); + } + + PointerKind PK = + Ty->getSizeInBits() == 64 ? PointerKind::Near64 : PointerKind::Near32; + PointerMode PM = PointerMode::Pointer; + switch (Ty->getTag()) { + default: llvm_unreachable("not a pointer tag type"); + case dwarf::DW_TAG_pointer_type: + PM = PointerMode::Pointer; + break; + case dwarf::DW_TAG_reference_type: + PM = PointerMode::LValueReference; + break; + case dwarf::DW_TAG_rvalue_reference_type: + PM = PointerMode::RValueReference; + break; + } + // FIXME: MSVC folds qualifiers into PointerOptions in the context of a method + // 'this' pointer, but not normal contexts. Figure out what we're supposed to + // do. + PointerOptions PO = PointerOptions::None; + PointerRecord PR(PointeeTI, PK, PM, PO, Ty->getSizeInBits() / 8); + return TypeTable.writeKnownType(PR); +} + +static PointerToMemberRepresentation +translatePtrToMemberRep(unsigned SizeInBytes, bool IsPMF, unsigned Flags) { + // SizeInBytes being zero generally implies that the member pointer type was + // incomplete, which can happen if it is part of a function prototype. In this + // case, use the unknown model instead of the general model. + if (IsPMF) { + switch (Flags & DINode::FlagPtrToMemberRep) { + case 0: + return SizeInBytes == 0 ? PointerToMemberRepresentation::Unknown + : PointerToMemberRepresentation::GeneralFunction; + case DINode::FlagSingleInheritance: + return PointerToMemberRepresentation::SingleInheritanceFunction; + case DINode::FlagMultipleInheritance: + return PointerToMemberRepresentation::MultipleInheritanceFunction; + case DINode::FlagVirtualInheritance: + return PointerToMemberRepresentation::VirtualInheritanceFunction; + } + } else { + switch (Flags & DINode::FlagPtrToMemberRep) { + case 0: + return SizeInBytes == 0 ? PointerToMemberRepresentation::Unknown + : PointerToMemberRepresentation::GeneralData; + case DINode::FlagSingleInheritance: + return PointerToMemberRepresentation::SingleInheritanceData; + case DINode::FlagMultipleInheritance: + return PointerToMemberRepresentation::MultipleInheritanceData; + case DINode::FlagVirtualInheritance: + return PointerToMemberRepresentation::VirtualInheritanceData; + } + } + llvm_unreachable("invalid ptr to member representation"); +} + +TypeIndex CodeViewDebug::lowerTypeMemberPointer(const DIDerivedType *Ty) { + assert(Ty->getTag() == dwarf::DW_TAG_ptr_to_member_type); + TypeIndex ClassTI = getTypeIndex(Ty->getClassType()); + TypeIndex PointeeTI = getTypeIndex(Ty->getBaseType(), Ty->getClassType()); + PointerKind PK = Asm->TM.getPointerSize() == 8 ? PointerKind::Near64 + : PointerKind::Near32; + bool IsPMF = isa<DISubroutineType>(Ty->getBaseType()); + PointerMode PM = IsPMF ? PointerMode::PointerToMemberFunction + : PointerMode::PointerToDataMember; + PointerOptions PO = PointerOptions::None; // FIXME + assert(Ty->getSizeInBits() / 8 <= 0xff && "pointer size too big"); + uint8_t SizeInBytes = Ty->getSizeInBits() / 8; + MemberPointerInfo MPI( + ClassTI, translatePtrToMemberRep(SizeInBytes, IsPMF, Ty->getFlags())); + PointerRecord PR(PointeeTI, PK, PM, PO, SizeInBytes, MPI); + return TypeTable.writeKnownType(PR); +} + +/// Given a DWARF calling convention, get the CodeView equivalent. If we don't +/// have a translation, use the NearC convention. +static CallingConvention dwarfCCToCodeView(unsigned DwarfCC) { + switch (DwarfCC) { + case dwarf::DW_CC_normal: return CallingConvention::NearC; + case dwarf::DW_CC_BORLAND_msfastcall: return CallingConvention::NearFast; + case dwarf::DW_CC_BORLAND_thiscall: return CallingConvention::ThisCall; + case dwarf::DW_CC_BORLAND_stdcall: return CallingConvention::NearStdCall; + case dwarf::DW_CC_BORLAND_pascal: return CallingConvention::NearPascal; + case dwarf::DW_CC_LLVM_vectorcall: return CallingConvention::NearVector; + } + return CallingConvention::NearC; +} + +TypeIndex CodeViewDebug::lowerTypeModifier(const DIDerivedType *Ty) { + ModifierOptions Mods = ModifierOptions::None; + bool IsModifier = true; + const DIType *BaseTy = Ty; + while (IsModifier && BaseTy) { + // FIXME: Need to add DWARF tags for __unaligned and _Atomic + switch (BaseTy->getTag()) { + case dwarf::DW_TAG_const_type: + Mods |= ModifierOptions::Const; + break; + case dwarf::DW_TAG_volatile_type: + Mods |= ModifierOptions::Volatile; + break; + default: + IsModifier = false; + break; + } + if (IsModifier) + BaseTy = cast<DIDerivedType>(BaseTy)->getBaseType().resolve(); + } + TypeIndex ModifiedTI = getTypeIndex(BaseTy); + ModifierRecord MR(ModifiedTI, Mods); + return TypeTable.writeKnownType(MR); +} + +TypeIndex CodeViewDebug::lowerTypeFunction(const DISubroutineType *Ty) { + SmallVector<TypeIndex, 8> ReturnAndArgTypeIndices; + for (DITypeRef ArgTypeRef : Ty->getTypeArray()) + ReturnAndArgTypeIndices.push_back(getTypeIndex(ArgTypeRef)); + + TypeIndex ReturnTypeIndex = TypeIndex::Void(); + ArrayRef<TypeIndex> ArgTypeIndices = None; + if (!ReturnAndArgTypeIndices.empty()) { + auto ReturnAndArgTypesRef = makeArrayRef(ReturnAndArgTypeIndices); + ReturnTypeIndex = ReturnAndArgTypesRef.front(); + ArgTypeIndices = ReturnAndArgTypesRef.drop_front(); + } + + ArgListRecord ArgListRec(TypeRecordKind::ArgList, ArgTypeIndices); + TypeIndex ArgListIndex = TypeTable.writeKnownType(ArgListRec); + + CallingConvention CC = dwarfCCToCodeView(Ty->getCC()); + + ProcedureRecord Procedure(ReturnTypeIndex, CC, FunctionOptions::None, + ArgTypeIndices.size(), ArgListIndex); + return TypeTable.writeKnownType(Procedure); +} + +TypeIndex CodeViewDebug::lowerTypeMemberFunction(const DISubroutineType *Ty, + const DIType *ClassTy, + int ThisAdjustment) { + // Lower the containing class type. + TypeIndex ClassType = getTypeIndex(ClassTy); + + SmallVector<TypeIndex, 8> ReturnAndArgTypeIndices; + for (DITypeRef ArgTypeRef : Ty->getTypeArray()) + ReturnAndArgTypeIndices.push_back(getTypeIndex(ArgTypeRef)); + + TypeIndex ReturnTypeIndex = TypeIndex::Void(); + ArrayRef<TypeIndex> ArgTypeIndices = None; + if (!ReturnAndArgTypeIndices.empty()) { + auto ReturnAndArgTypesRef = makeArrayRef(ReturnAndArgTypeIndices); + ReturnTypeIndex = ReturnAndArgTypesRef.front(); + ArgTypeIndices = ReturnAndArgTypesRef.drop_front(); + } + TypeIndex ThisTypeIndex = TypeIndex::Void(); + if (!ArgTypeIndices.empty()) { + ThisTypeIndex = ArgTypeIndices.front(); + ArgTypeIndices = ArgTypeIndices.drop_front(); + } + + ArgListRecord ArgListRec(TypeRecordKind::ArgList, ArgTypeIndices); + TypeIndex ArgListIndex = TypeTable.writeKnownType(ArgListRec); + + CallingConvention CC = dwarfCCToCodeView(Ty->getCC()); + + // TODO: Need to use the correct values for: + // FunctionOptions + // ThisPointerAdjustment. + MemberFunctionRecord MFR(ReturnTypeIndex, ClassType, ThisTypeIndex, CC, + FunctionOptions::None, ArgTypeIndices.size(), + ArgListIndex, ThisAdjustment); + TypeIndex TI = TypeTable.writeKnownType(MFR); + + return TI; +} + +TypeIndex CodeViewDebug::lowerTypeVFTableShape(const DIDerivedType *Ty) { + unsigned VSlotCount = + Ty->getSizeInBits() / (8 * Asm->MAI->getCodePointerSize()); + SmallVector<VFTableSlotKind, 4> Slots(VSlotCount, VFTableSlotKind::Near); + + VFTableShapeRecord VFTSR(Slots); + return TypeTable.writeKnownType(VFTSR); +} + +static MemberAccess translateAccessFlags(unsigned RecordTag, unsigned Flags) { + switch (Flags & DINode::FlagAccessibility) { + case DINode::FlagPrivate: return MemberAccess::Private; + case DINode::FlagPublic: return MemberAccess::Public; + case DINode::FlagProtected: return MemberAccess::Protected; + case 0: + // If there was no explicit access control, provide the default for the tag. + return RecordTag == dwarf::DW_TAG_class_type ? MemberAccess::Private + : MemberAccess::Public; + } + llvm_unreachable("access flags are exclusive"); +} + +static MethodOptions translateMethodOptionFlags(const DISubprogram *SP) { + if (SP->isArtificial()) + return MethodOptions::CompilerGenerated; + + // FIXME: Handle other MethodOptions. + + return MethodOptions::None; +} + +static MethodKind translateMethodKindFlags(const DISubprogram *SP, + bool Introduced) { + switch (SP->getVirtuality()) { + case dwarf::DW_VIRTUALITY_none: + break; + case dwarf::DW_VIRTUALITY_virtual: + return Introduced ? MethodKind::IntroducingVirtual : MethodKind::Virtual; + case dwarf::DW_VIRTUALITY_pure_virtual: + return Introduced ? MethodKind::PureIntroducingVirtual + : MethodKind::PureVirtual; + default: + llvm_unreachable("unhandled virtuality case"); + } + + // FIXME: Get Clang to mark DISubprogram as static and do something with it. + + return MethodKind::Vanilla; +} + +static TypeRecordKind getRecordKind(const DICompositeType *Ty) { + switch (Ty->getTag()) { + case dwarf::DW_TAG_class_type: return TypeRecordKind::Class; + case dwarf::DW_TAG_structure_type: return TypeRecordKind::Struct; + } + llvm_unreachable("unexpected tag"); +} + +/// Return ClassOptions that should be present on both the forward declaration +/// and the defintion of a tag type. +static ClassOptions getCommonClassOptions(const DICompositeType *Ty) { + ClassOptions CO = ClassOptions::None; + + // MSVC always sets this flag, even for local types. Clang doesn't always + // appear to give every type a linkage name, which may be problematic for us. + // FIXME: Investigate the consequences of not following them here. + if (!Ty->getIdentifier().empty()) + CO |= ClassOptions::HasUniqueName; + + // Put the Nested flag on a type if it appears immediately inside a tag type. + // Do not walk the scope chain. Do not attempt to compute ContainsNestedClass + // here. That flag is only set on definitions, and not forward declarations. + const DIScope *ImmediateScope = Ty->getScope().resolve(); + if (ImmediateScope && isa<DICompositeType>(ImmediateScope)) + CO |= ClassOptions::Nested; + + // Put the Scoped flag on function-local types. + for (const DIScope *Scope = ImmediateScope; Scope != nullptr; + Scope = Scope->getScope().resolve()) { + if (isa<DISubprogram>(Scope)) { + CO |= ClassOptions::Scoped; + break; + } + } + + return CO; +} + +TypeIndex CodeViewDebug::lowerTypeEnum(const DICompositeType *Ty) { + ClassOptions CO = getCommonClassOptions(Ty); + TypeIndex FTI; + unsigned EnumeratorCount = 0; + + if (Ty->isForwardDecl()) { + CO |= ClassOptions::ForwardReference; + } else { + FieldListRecordBuilder FLRB(TypeTable); + + FLRB.begin(); + for (const DINode *Element : Ty->getElements()) { + // We assume that the frontend provides all members in source declaration + // order, which is what MSVC does. + if (auto *Enumerator = dyn_cast_or_null<DIEnumerator>(Element)) { + EnumeratorRecord ER(MemberAccess::Public, + APSInt::getUnsigned(Enumerator->getValue()), + Enumerator->getName()); + FLRB.writeMemberType(ER); + EnumeratorCount++; + } + } + FTI = FLRB.end(); + } + + std::string FullName = getFullyQualifiedName(Ty); + + EnumRecord ER(EnumeratorCount, CO, FTI, FullName, Ty->getIdentifier(), + getTypeIndex(Ty->getBaseType())); + return TypeTable.writeKnownType(ER); +} + +//===----------------------------------------------------------------------===// +// ClassInfo +//===----------------------------------------------------------------------===// + +struct llvm::ClassInfo { + struct MemberInfo { + const DIDerivedType *MemberTypeNode; + uint64_t BaseOffset; + }; + // [MemberInfo] + typedef std::vector<MemberInfo> MemberList; + + typedef TinyPtrVector<const DISubprogram *> MethodsList; + // MethodName -> MethodsList + typedef MapVector<MDString *, MethodsList> MethodsMap; + + /// Base classes. + std::vector<const DIDerivedType *> Inheritance; + + /// Direct members. + MemberList Members; + // Direct overloaded methods gathered by name. + MethodsMap Methods; + + TypeIndex VShapeTI; + + std::vector<const DICompositeType *> NestedClasses; +}; + +void CodeViewDebug::clear() { + assert(CurFn == nullptr); + FileIdMap.clear(); + FnDebugInfo.clear(); + FileToFilepathMap.clear(); + LocalUDTs.clear(); + GlobalUDTs.clear(); + TypeIndices.clear(); + CompleteTypeIndices.clear(); +} + +void CodeViewDebug::collectMemberInfo(ClassInfo &Info, + const DIDerivedType *DDTy) { + if (!DDTy->getName().empty()) { + Info.Members.push_back({DDTy, 0}); + return; + } + // An unnamed member must represent a nested struct or union. Add all the + // indirect fields to the current record. + assert((DDTy->getOffsetInBits() % 8) == 0 && "Unnamed bitfield member!"); + uint64_t Offset = DDTy->getOffsetInBits(); + const DIType *Ty = DDTy->getBaseType().resolve(); + const DICompositeType *DCTy = cast<DICompositeType>(Ty); + ClassInfo NestedInfo = collectClassInfo(DCTy); + for (const ClassInfo::MemberInfo &IndirectField : NestedInfo.Members) + Info.Members.push_back( + {IndirectField.MemberTypeNode, IndirectField.BaseOffset + Offset}); +} + +ClassInfo CodeViewDebug::collectClassInfo(const DICompositeType *Ty) { + ClassInfo Info; + // Add elements to structure type. + DINodeArray Elements = Ty->getElements(); + for (auto *Element : Elements) { + // We assume that the frontend provides all members in source declaration + // order, which is what MSVC does. + if (!Element) + continue; + if (auto *SP = dyn_cast<DISubprogram>(Element)) { + Info.Methods[SP->getRawName()].push_back(SP); + } else if (auto *DDTy = dyn_cast<DIDerivedType>(Element)) { + if (DDTy->getTag() == dwarf::DW_TAG_member) { + collectMemberInfo(Info, DDTy); + } else if (DDTy->getTag() == dwarf::DW_TAG_inheritance) { + Info.Inheritance.push_back(DDTy); + } else if (DDTy->getTag() == dwarf::DW_TAG_pointer_type && + DDTy->getName() == "__vtbl_ptr_type") { + Info.VShapeTI = getTypeIndex(DDTy); + } else if (DDTy->getTag() == dwarf::DW_TAG_friend) { + // Ignore friend members. It appears that MSVC emitted info about + // friends in the past, but modern versions do not. + } + } else if (auto *Composite = dyn_cast<DICompositeType>(Element)) { + Info.NestedClasses.push_back(Composite); + } + // Skip other unrecognized kinds of elements. + } + return Info; +} + +TypeIndex CodeViewDebug::lowerTypeClass(const DICompositeType *Ty) { + // First, construct the forward decl. Don't look into Ty to compute the + // forward decl options, since it might not be available in all TUs. + TypeRecordKind Kind = getRecordKind(Ty); + ClassOptions CO = + ClassOptions::ForwardReference | getCommonClassOptions(Ty); + std::string FullName = getFullyQualifiedName(Ty); + ClassRecord CR(Kind, 0, CO, TypeIndex(), TypeIndex(), TypeIndex(), 0, + FullName, Ty->getIdentifier()); + TypeIndex FwdDeclTI = TypeTable.writeKnownType(CR); + if (!Ty->isForwardDecl()) + DeferredCompleteTypes.push_back(Ty); + return FwdDeclTI; +} + +TypeIndex CodeViewDebug::lowerCompleteTypeClass(const DICompositeType *Ty) { + // Construct the field list and complete type record. + TypeRecordKind Kind = getRecordKind(Ty); + ClassOptions CO = getCommonClassOptions(Ty); + TypeIndex FieldTI; + TypeIndex VShapeTI; + unsigned FieldCount; + bool ContainsNestedClass; + std::tie(FieldTI, VShapeTI, FieldCount, ContainsNestedClass) = + lowerRecordFieldList(Ty); + + if (ContainsNestedClass) + CO |= ClassOptions::ContainsNestedClass; + + std::string FullName = getFullyQualifiedName(Ty); + + uint64_t SizeInBytes = Ty->getSizeInBits() / 8; + + ClassRecord CR(Kind, FieldCount, CO, FieldTI, TypeIndex(), VShapeTI, + SizeInBytes, FullName, Ty->getIdentifier()); + TypeIndex ClassTI = TypeTable.writeKnownType(CR); + + StringIdRecord SIDR(TypeIndex(0x0), getFullFilepath(Ty->getFile())); + TypeIndex SIDI = TypeTable.writeKnownType(SIDR); + UdtSourceLineRecord USLR(ClassTI, SIDI, Ty->getLine()); + TypeTable.writeKnownType(USLR); + + addToUDTs(Ty, ClassTI); + + return ClassTI; +} + +TypeIndex CodeViewDebug::lowerTypeUnion(const DICompositeType *Ty) { + ClassOptions CO = + ClassOptions::ForwardReference | getCommonClassOptions(Ty); + std::string FullName = getFullyQualifiedName(Ty); + UnionRecord UR(0, CO, TypeIndex(), 0, FullName, Ty->getIdentifier()); + TypeIndex FwdDeclTI = TypeTable.writeKnownType(UR); + if (!Ty->isForwardDecl()) + DeferredCompleteTypes.push_back(Ty); + return FwdDeclTI; +} + +TypeIndex CodeViewDebug::lowerCompleteTypeUnion(const DICompositeType *Ty) { + ClassOptions CO = ClassOptions::Sealed | getCommonClassOptions(Ty); + TypeIndex FieldTI; + unsigned FieldCount; + bool ContainsNestedClass; + std::tie(FieldTI, std::ignore, FieldCount, ContainsNestedClass) = + lowerRecordFieldList(Ty); + + if (ContainsNestedClass) + CO |= ClassOptions::ContainsNestedClass; + + uint64_t SizeInBytes = Ty->getSizeInBits() / 8; + std::string FullName = getFullyQualifiedName(Ty); + + UnionRecord UR(FieldCount, CO, FieldTI, SizeInBytes, FullName, + Ty->getIdentifier()); + TypeIndex UnionTI = TypeTable.writeKnownType(UR); + + StringIdRecord SIR(TypeIndex(0x0), getFullFilepath(Ty->getFile())); + TypeIndex SIRI = TypeTable.writeKnownType(SIR); + UdtSourceLineRecord USLR(UnionTI, SIRI, Ty->getLine()); + TypeTable.writeKnownType(USLR); + + addToUDTs(Ty, UnionTI); + + return UnionTI; +} + +std::tuple<TypeIndex, TypeIndex, unsigned, bool> +CodeViewDebug::lowerRecordFieldList(const DICompositeType *Ty) { + // Manually count members. MSVC appears to count everything that generates a + // field list record. Each individual overload in a method overload group + // contributes to this count, even though the overload group is a single field + // list record. + unsigned MemberCount = 0; + ClassInfo Info = collectClassInfo(Ty); + FieldListRecordBuilder FLBR(TypeTable); + FLBR.begin(); + + // Create base classes. + for (const DIDerivedType *I : Info.Inheritance) { + if (I->getFlags() & DINode::FlagVirtual) { + // Virtual base. + // FIXME: Emit VBPtrOffset when the frontend provides it. + unsigned VBPtrOffset = 0; + // FIXME: Despite the accessor name, the offset is really in bytes. + unsigned VBTableIndex = I->getOffsetInBits() / 4; + auto RecordKind = (I->getFlags() & DINode::FlagIndirectVirtualBase) == DINode::FlagIndirectVirtualBase + ? TypeRecordKind::IndirectVirtualBaseClass + : TypeRecordKind::VirtualBaseClass; + VirtualBaseClassRecord VBCR( + RecordKind, translateAccessFlags(Ty->getTag(), I->getFlags()), + getTypeIndex(I->getBaseType()), getVBPTypeIndex(), VBPtrOffset, + VBTableIndex); + + FLBR.writeMemberType(VBCR); + } else { + assert(I->getOffsetInBits() % 8 == 0 && + "bases must be on byte boundaries"); + BaseClassRecord BCR(translateAccessFlags(Ty->getTag(), I->getFlags()), + getTypeIndex(I->getBaseType()), + I->getOffsetInBits() / 8); + FLBR.writeMemberType(BCR); + } + } + + // Create members. + for (ClassInfo::MemberInfo &MemberInfo : Info.Members) { + const DIDerivedType *Member = MemberInfo.MemberTypeNode; + TypeIndex MemberBaseType = getTypeIndex(Member->getBaseType()); + StringRef MemberName = Member->getName(); + MemberAccess Access = + translateAccessFlags(Ty->getTag(), Member->getFlags()); + + if (Member->isStaticMember()) { + StaticDataMemberRecord SDMR(Access, MemberBaseType, MemberName); + FLBR.writeMemberType(SDMR); + MemberCount++; + continue; + } + + // Virtual function pointer member. + if ((Member->getFlags() & DINode::FlagArtificial) && + Member->getName().startswith("_vptr$")) { + VFPtrRecord VFPR(getTypeIndex(Member->getBaseType())); + FLBR.writeMemberType(VFPR); + MemberCount++; + continue; + } + + // Data member. + uint64_t MemberOffsetInBits = + Member->getOffsetInBits() + MemberInfo.BaseOffset; + if (Member->isBitField()) { + uint64_t StartBitOffset = MemberOffsetInBits; + if (const auto *CI = + dyn_cast_or_null<ConstantInt>(Member->getStorageOffsetInBits())) { + MemberOffsetInBits = CI->getZExtValue() + MemberInfo.BaseOffset; + } + StartBitOffset -= MemberOffsetInBits; + BitFieldRecord BFR(MemberBaseType, Member->getSizeInBits(), + StartBitOffset); + MemberBaseType = TypeTable.writeKnownType(BFR); + } + uint64_t MemberOffsetInBytes = MemberOffsetInBits / 8; + DataMemberRecord DMR(Access, MemberBaseType, MemberOffsetInBytes, + MemberName); + FLBR.writeMemberType(DMR); + MemberCount++; + } + + // Create methods + for (auto &MethodItr : Info.Methods) { + StringRef Name = MethodItr.first->getString(); + + std::vector<OneMethodRecord> Methods; + for (const DISubprogram *SP : MethodItr.second) { + TypeIndex MethodType = getMemberFunctionType(SP, Ty); + bool Introduced = SP->getFlags() & DINode::FlagIntroducedVirtual; + + unsigned VFTableOffset = -1; + if (Introduced) + VFTableOffset = SP->getVirtualIndex() * getPointerSizeInBytes(); + + Methods.push_back(OneMethodRecord( + MethodType, translateAccessFlags(Ty->getTag(), SP->getFlags()), + translateMethodKindFlags(SP, Introduced), + translateMethodOptionFlags(SP), VFTableOffset, Name)); + MemberCount++; + } + assert(Methods.size() > 0 && "Empty methods map entry"); + if (Methods.size() == 1) + FLBR.writeMemberType(Methods[0]); + else { + MethodOverloadListRecord MOLR(Methods); + TypeIndex MethodList = TypeTable.writeKnownType(MOLR); + OverloadedMethodRecord OMR(Methods.size(), MethodList, Name); + FLBR.writeMemberType(OMR); + } + } + + // Create nested classes. + for (const DICompositeType *Nested : Info.NestedClasses) { + NestedTypeRecord R(getTypeIndex(DITypeRef(Nested)), Nested->getName()); + FLBR.writeMemberType(R); + MemberCount++; + } + + TypeIndex FieldTI = FLBR.end(); + return std::make_tuple(FieldTI, Info.VShapeTI, MemberCount, + !Info.NestedClasses.empty()); +} + +TypeIndex CodeViewDebug::getVBPTypeIndex() { + if (!VBPType.getIndex()) { + // Make a 'const int *' type. + ModifierRecord MR(TypeIndex::Int32(), ModifierOptions::Const); + TypeIndex ModifiedTI = TypeTable.writeKnownType(MR); + + PointerKind PK = getPointerSizeInBytes() == 8 ? PointerKind::Near64 + : PointerKind::Near32; + PointerMode PM = PointerMode::Pointer; + PointerOptions PO = PointerOptions::None; + PointerRecord PR(ModifiedTI, PK, PM, PO, getPointerSizeInBytes()); + + VBPType = TypeTable.writeKnownType(PR); + } + + return VBPType; +} + +TypeIndex CodeViewDebug::getTypeIndex(DITypeRef TypeRef, DITypeRef ClassTyRef) { + const DIType *Ty = TypeRef.resolve(); + const DIType *ClassTy = ClassTyRef.resolve(); + + // The null DIType is the void type. Don't try to hash it. + if (!Ty) + return TypeIndex::Void(); + + // Check if we've already translated this type. Don't try to do a + // get-or-create style insertion that caches the hash lookup across the + // lowerType call. It will update the TypeIndices map. + auto I = TypeIndices.find({Ty, ClassTy}); + if (I != TypeIndices.end()) + return I->second; + + TypeLoweringScope S(*this); + TypeIndex TI = lowerType(Ty, ClassTy); + return recordTypeIndexForDINode(Ty, TI, ClassTy); +} + +TypeIndex CodeViewDebug::getCompleteTypeIndex(DITypeRef TypeRef) { + const DIType *Ty = TypeRef.resolve(); + + // The null DIType is the void type. Don't try to hash it. + if (!Ty) + return TypeIndex::Void(); + + // If this is a non-record type, the complete type index is the same as the + // normal type index. Just call getTypeIndex. + switch (Ty->getTag()) { + case dwarf::DW_TAG_class_type: + case dwarf::DW_TAG_structure_type: + case dwarf::DW_TAG_union_type: + break; + default: + return getTypeIndex(Ty); + } + + // Check if we've already translated the complete record type. Lowering a + // complete type should never trigger lowering another complete type, so we + // can reuse the hash table lookup result. + const auto *CTy = cast<DICompositeType>(Ty); + auto InsertResult = CompleteTypeIndices.insert({CTy, TypeIndex()}); + if (!InsertResult.second) + return InsertResult.first->second; + + TypeLoweringScope S(*this); + + // Make sure the forward declaration is emitted first. It's unclear if this + // is necessary, but MSVC does it, and we should follow suit until we can show + // otherwise. + TypeIndex FwdDeclTI = getTypeIndex(CTy); + + // Just use the forward decl if we don't have complete type info. This might + // happen if the frontend is using modules and expects the complete definition + // to be emitted elsewhere. + if (CTy->isForwardDecl()) + return FwdDeclTI; + + TypeIndex TI; + switch (CTy->getTag()) { + case dwarf::DW_TAG_class_type: + case dwarf::DW_TAG_structure_type: + TI = lowerCompleteTypeClass(CTy); + break; + case dwarf::DW_TAG_union_type: + TI = lowerCompleteTypeUnion(CTy); + break; + default: + llvm_unreachable("not a record"); + } + + InsertResult.first->second = TI; + return TI; +} + +/// Emit all the deferred complete record types. Try to do this in FIFO order, +/// and do this until fixpoint, as each complete record type typically +/// references +/// many other record types. +void CodeViewDebug::emitDeferredCompleteTypes() { + SmallVector<const DICompositeType *, 4> TypesToEmit; + while (!DeferredCompleteTypes.empty()) { + std::swap(DeferredCompleteTypes, TypesToEmit); + for (const DICompositeType *RecordTy : TypesToEmit) + getCompleteTypeIndex(RecordTy); + TypesToEmit.clear(); + } +} + +void CodeViewDebug::emitLocalVariableList(ArrayRef<LocalVariable> Locals) { + // Get the sorted list of parameters and emit them first. + SmallVector<const LocalVariable *, 6> Params; + for (const LocalVariable &L : Locals) + if (L.DIVar->isParameter()) + Params.push_back(&L); + std::sort(Params.begin(), Params.end(), + [](const LocalVariable *L, const LocalVariable *R) { + return L->DIVar->getArg() < R->DIVar->getArg(); + }); + for (const LocalVariable *L : Params) + emitLocalVariable(*L); + + // Next emit all non-parameters in the order that we found them. + for (const LocalVariable &L : Locals) + if (!L.DIVar->isParameter()) + emitLocalVariable(L); +} + +void CodeViewDebug::emitLocalVariable(const LocalVariable &Var) { + // LocalSym record, see SymbolRecord.h for more info. + MCSymbol *LocalBegin = MMI->getContext().createTempSymbol(), + *LocalEnd = MMI->getContext().createTempSymbol(); + OS.AddComment("Record length"); + OS.emitAbsoluteSymbolDiff(LocalEnd, LocalBegin, 2); + OS.EmitLabel(LocalBegin); + + OS.AddComment("Record kind: S_LOCAL"); + OS.EmitIntValue(unsigned(SymbolKind::S_LOCAL), 2); + + LocalSymFlags Flags = LocalSymFlags::None; + if (Var.DIVar->isParameter()) + Flags |= LocalSymFlags::IsParameter; + if (Var.DefRanges.empty()) + Flags |= LocalSymFlags::IsOptimizedOut; + + OS.AddComment("TypeIndex"); + TypeIndex TI = getCompleteTypeIndex(Var.DIVar->getType()); + OS.EmitIntValue(TI.getIndex(), 4); + OS.AddComment("Flags"); + OS.EmitIntValue(static_cast<uint16_t>(Flags), 2); + // Truncate the name so we won't overflow the record length field. + emitNullTerminatedSymbolName(OS, Var.DIVar->getName()); + OS.EmitLabel(LocalEnd); + + // Calculate the on disk prefix of the appropriate def range record. The + // records and on disk formats are described in SymbolRecords.h. BytePrefix + // should be big enough to hold all forms without memory allocation. + SmallString<20> BytePrefix; + for (const LocalVarDefRange &DefRange : Var.DefRanges) { + BytePrefix.clear(); + if (DefRange.InMemory) { + uint16_t RegRelFlags = 0; + if (DefRange.IsSubfield) { + RegRelFlags = DefRangeRegisterRelSym::IsSubfieldFlag | + (DefRange.StructOffset + << DefRangeRegisterRelSym::OffsetInParentShift); + } + DefRangeRegisterRelSym Sym(S_DEFRANGE_REGISTER_REL); + Sym.Hdr.Register = DefRange.CVRegister; + Sym.Hdr.Flags = RegRelFlags; + Sym.Hdr.BasePointerOffset = DefRange.DataOffset; + ulittle16_t SymKind = ulittle16_t(S_DEFRANGE_REGISTER_REL); + BytePrefix += + StringRef(reinterpret_cast<const char *>(&SymKind), sizeof(SymKind)); + BytePrefix += + StringRef(reinterpret_cast<const char *>(&Sym.Hdr), sizeof(Sym.Hdr)); + } else { + assert(DefRange.DataOffset == 0 && "unexpected offset into register"); + if (DefRange.IsSubfield) { + // Unclear what matters here. + DefRangeSubfieldRegisterSym Sym(S_DEFRANGE_SUBFIELD_REGISTER); + Sym.Hdr.Register = DefRange.CVRegister; + Sym.Hdr.MayHaveNoName = 0; + Sym.Hdr.OffsetInParent = DefRange.StructOffset; + + ulittle16_t SymKind = ulittle16_t(S_DEFRANGE_SUBFIELD_REGISTER); + BytePrefix += StringRef(reinterpret_cast<const char *>(&SymKind), + sizeof(SymKind)); + BytePrefix += StringRef(reinterpret_cast<const char *>(&Sym.Hdr), + sizeof(Sym.Hdr)); + } else { + // Unclear what matters here. + DefRangeRegisterSym Sym(S_DEFRANGE_REGISTER); + Sym.Hdr.Register = DefRange.CVRegister; + Sym.Hdr.MayHaveNoName = 0; + ulittle16_t SymKind = ulittle16_t(S_DEFRANGE_REGISTER); + BytePrefix += StringRef(reinterpret_cast<const char *>(&SymKind), + sizeof(SymKind)); + BytePrefix += StringRef(reinterpret_cast<const char *>(&Sym.Hdr), + sizeof(Sym.Hdr)); + } + } + OS.EmitCVDefRangeDirective(DefRange.Ranges, BytePrefix); + } +} + +void CodeViewDebug::endFunctionImpl(const MachineFunction *MF) { + const Function *GV = MF->getFunction(); + assert(FnDebugInfo.count(GV)); + assert(CurFn == &FnDebugInfo[GV]); + + collectVariableInfo(GV->getSubprogram()); + + // Don't emit anything if we don't have any line tables. + if (!CurFn->HaveLineInfo) { + FnDebugInfo.erase(GV); + CurFn = nullptr; + return; + } + + CurFn->End = Asm->getFunctionEnd(); + + CurFn = nullptr; +} + +void CodeViewDebug::beginInstruction(const MachineInstr *MI) { + DebugHandlerBase::beginInstruction(MI); + + // Ignore DBG_VALUE locations and function prologue. + if (!Asm || !CurFn || MI->isDebugValue() || + MI->getFlag(MachineInstr::FrameSetup)) + return; + DebugLoc DL = MI->getDebugLoc(); + if (DL == PrevInstLoc || !DL) + return; + maybeRecordLocation(DL, Asm->MF); +} + +MCSymbol *CodeViewDebug::beginCVSubsection(ModuleDebugFragmentKind Kind) { + MCSymbol *BeginLabel = MMI->getContext().createTempSymbol(), + *EndLabel = MMI->getContext().createTempSymbol(); + OS.EmitIntValue(unsigned(Kind), 4); + OS.AddComment("Subsection size"); + OS.emitAbsoluteSymbolDiff(EndLabel, BeginLabel, 4); + OS.EmitLabel(BeginLabel); + return EndLabel; +} + +void CodeViewDebug::endCVSubsection(MCSymbol *EndLabel) { + OS.EmitLabel(EndLabel); + // Every subsection must be aligned to a 4-byte boundary. + OS.EmitValueToAlignment(4); +} + +void CodeViewDebug::emitDebugInfoForUDTs( + ArrayRef<std::pair<std::string, TypeIndex>> UDTs) { + for (const std::pair<std::string, codeview::TypeIndex> &UDT : UDTs) { + MCSymbol *UDTRecordBegin = MMI->getContext().createTempSymbol(), + *UDTRecordEnd = MMI->getContext().createTempSymbol(); + OS.AddComment("Record length"); + OS.emitAbsoluteSymbolDiff(UDTRecordEnd, UDTRecordBegin, 2); + OS.EmitLabel(UDTRecordBegin); + + OS.AddComment("Record kind: S_UDT"); + OS.EmitIntValue(unsigned(SymbolKind::S_UDT), 2); + + OS.AddComment("Type"); + OS.EmitIntValue(UDT.second.getIndex(), 4); + + emitNullTerminatedSymbolName(OS, UDT.first); + OS.EmitLabel(UDTRecordEnd); + } +} + +void CodeViewDebug::emitDebugInfoForGlobals() { + DenseMap<const DIGlobalVariableExpression *, const GlobalVariable *> + GlobalMap; + for (const GlobalVariable &GV : MMI->getModule()->globals()) { + SmallVector<DIGlobalVariableExpression *, 1> GVEs; + GV.getDebugInfo(GVEs); + for (const auto *GVE : GVEs) + GlobalMap[GVE] = &GV; + } + + NamedMDNode *CUs = MMI->getModule()->getNamedMetadata("llvm.dbg.cu"); + for (const MDNode *Node : CUs->operands()) { + const auto *CU = cast<DICompileUnit>(Node); + + // First, emit all globals that are not in a comdat in a single symbol + // substream. MSVC doesn't like it if the substream is empty, so only open + // it if we have at least one global to emit. + switchToDebugSectionForSymbol(nullptr); + MCSymbol *EndLabel = nullptr; + for (const auto *GVE : CU->getGlobalVariables()) { + if (const auto *GV = GlobalMap.lookup(GVE)) + if (!GV->hasComdat() && !GV->isDeclarationForLinker()) { + if (!EndLabel) { + OS.AddComment("Symbol subsection for globals"); + EndLabel = beginCVSubsection(ModuleDebugFragmentKind::Symbols); + } + // FIXME: emitDebugInfoForGlobal() doesn't handle DIExpressions. + emitDebugInfoForGlobal(GVE->getVariable(), GV, Asm->getSymbol(GV)); + } + } + if (EndLabel) + endCVSubsection(EndLabel); + + // Second, emit each global that is in a comdat into its own .debug$S + // section along with its own symbol substream. + for (const auto *GVE : CU->getGlobalVariables()) { + if (const auto *GV = GlobalMap.lookup(GVE)) { + if (GV->hasComdat()) { + MCSymbol *GVSym = Asm->getSymbol(GV); + OS.AddComment("Symbol subsection for " + + Twine(GlobalValue::getRealLinkageName(GV->getName()))); + switchToDebugSectionForSymbol(GVSym); + EndLabel = beginCVSubsection(ModuleDebugFragmentKind::Symbols); + // FIXME: emitDebugInfoForGlobal() doesn't handle DIExpressions. + emitDebugInfoForGlobal(GVE->getVariable(), GV, GVSym); + endCVSubsection(EndLabel); + } + } + } + } +} + +void CodeViewDebug::emitDebugInfoForRetainedTypes() { + NamedMDNode *CUs = MMI->getModule()->getNamedMetadata("llvm.dbg.cu"); + for (const MDNode *Node : CUs->operands()) { + for (auto *Ty : cast<DICompileUnit>(Node)->getRetainedTypes()) { + if (DIType *RT = dyn_cast<DIType>(Ty)) { + getTypeIndex(RT); + // FIXME: Add to global/local DTU list. + } + } + } +} + +void CodeViewDebug::emitDebugInfoForGlobal(const DIGlobalVariable *DIGV, + const GlobalVariable *GV, + MCSymbol *GVSym) { + // DataSym record, see SymbolRecord.h for more info. + // FIXME: Thread local data, etc + MCSymbol *DataBegin = MMI->getContext().createTempSymbol(), + *DataEnd = MMI->getContext().createTempSymbol(); + OS.AddComment("Record length"); + OS.emitAbsoluteSymbolDiff(DataEnd, DataBegin, 2); + OS.EmitLabel(DataBegin); + if (DIGV->isLocalToUnit()) { + if (GV->isThreadLocal()) { + OS.AddComment("Record kind: S_LTHREAD32"); + OS.EmitIntValue(unsigned(SymbolKind::S_LTHREAD32), 2); + } else { + OS.AddComment("Record kind: S_LDATA32"); + OS.EmitIntValue(unsigned(SymbolKind::S_LDATA32), 2); + } + } else { + if (GV->isThreadLocal()) { + OS.AddComment("Record kind: S_GTHREAD32"); + OS.EmitIntValue(unsigned(SymbolKind::S_GTHREAD32), 2); + } else { + OS.AddComment("Record kind: S_GDATA32"); + OS.EmitIntValue(unsigned(SymbolKind::S_GDATA32), 2); + } + } + OS.AddComment("Type"); + OS.EmitIntValue(getCompleteTypeIndex(DIGV->getType()).getIndex(), 4); + OS.AddComment("DataOffset"); + OS.EmitCOFFSecRel32(GVSym, /*Offset=*/0); + OS.AddComment("Segment"); + OS.EmitCOFFSectionIndex(GVSym); + OS.AddComment("Name"); + emitNullTerminatedSymbolName(OS, DIGV->getName()); + OS.EmitLabel(DataEnd); +} |