1//===- llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp ----------------------===//
2//
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
6//
7//===----------------------------------------------------------------------===//
8//
9// This file contains support for writing Microsoft CodeView debug info.
10//
11//===----------------------------------------------------------------------===//
12
13#include "CodeViewDebug.h"
14#include "llvm/ADT/APSInt.h"
15#include "llvm/ADT/STLExtras.h"
16#include "llvm/ADT/SmallBitVector.h"
17#include "llvm/ADT/SmallString.h"
18#include "llvm/ADT/StringRef.h"
19#include "llvm/ADT/TinyPtrVector.h"
20#include "llvm/ADT/Twine.h"
21#include "llvm/BinaryFormat/COFF.h"
22#include "llvm/BinaryFormat/Dwarf.h"
23#include "llvm/CodeGen/AsmPrinter.h"
24#include "llvm/CodeGen/LexicalScopes.h"
25#include "llvm/CodeGen/MachineFrameInfo.h"
26#include "llvm/CodeGen/MachineFunction.h"
27#include "llvm/CodeGen/MachineInstr.h"
28#include "llvm/CodeGen/MachineModuleInfo.h"
29#include "llvm/CodeGen/TargetFrameLowering.h"
30#include "llvm/CodeGen/TargetLowering.h"
31#include "llvm/CodeGen/TargetRegisterInfo.h"
32#include "llvm/CodeGen/TargetSubtargetInfo.h"
33#include "llvm/Config/llvm-config.h"
34#include "llvm/DebugInfo/CodeView/CVTypeVisitor.h"
35#include "llvm/DebugInfo/CodeView/CodeViewRecordIO.h"
36#include "llvm/DebugInfo/CodeView/ContinuationRecordBuilder.h"
37#include "llvm/DebugInfo/CodeView/DebugInlineeLinesSubsection.h"
38#include "llvm/DebugInfo/CodeView/EnumTables.h"
39#include "llvm/DebugInfo/CodeView/Line.h"
40#include "llvm/DebugInfo/CodeView/SymbolRecord.h"
41#include "llvm/DebugInfo/CodeView/TypeRecord.h"
42#include "llvm/DebugInfo/CodeView/TypeTableCollection.h"
43#include "llvm/DebugInfo/CodeView/TypeVisitorCallbackPipeline.h"
44#include "llvm/IR/Constants.h"
45#include "llvm/IR/DataLayout.h"
46#include "llvm/IR/DebugInfoMetadata.h"
47#include "llvm/IR/Function.h"
48#include "llvm/IR/GlobalValue.h"
49#include "llvm/IR/GlobalVariable.h"
50#include "llvm/IR/Metadata.h"
51#include "llvm/IR/Module.h"
52#include "llvm/MC/MCAsmInfo.h"
53#include "llvm/MC/MCContext.h"
54#include "llvm/MC/MCSectionCOFF.h"
55#include "llvm/MC/MCStreamer.h"
56#include "llvm/MC/MCSymbol.h"
57#include "llvm/Support/BinaryStreamWriter.h"
58#include "llvm/Support/Casting.h"
59#include "llvm/Support/Error.h"
60#include "llvm/Support/ErrorHandling.h"
61#include "llvm/Support/FormatVariadic.h"
62#include "llvm/Support/Path.h"
63#include "llvm/Support/SMLoc.h"
64#include "llvm/Support/ScopedPrinter.h"
65#include "llvm/Target/TargetLoweringObjectFile.h"
66#include "llvm/Target/TargetMachine.h"
67#include "llvm/TargetParser/Triple.h"
68#include <algorithm>
69#include <cassert>
70#include <cctype>
71#include <cstddef>
72#include <limits>
73
74using namespace llvm;
75using namespace llvm::codeview;
76
77namespace {
78class CVMCAdapter : public CodeViewRecordStreamer {
79public:
80 CVMCAdapter(MCStreamer &OS, TypeCollection &TypeTable)
81 : OS(&OS), TypeTable(TypeTable) {}
82
83 void emitBytes(StringRef Data) override { OS->emitBytes(Data); }
84
85 void emitIntValue(uint64_t Value, unsigned Size) override {
86 OS->emitIntValueInHex(Value, Size);
87 }
88
89 void emitBinaryData(StringRef Data) override { OS->emitBinaryData(Data); }
90
91 void AddComment(const Twine &T) override { OS->AddComment(T); }
92
93 void AddRawComment(const Twine &T) override { OS->emitRawComment(T); }
94
95 bool isVerboseAsm() override { return OS->isVerboseAsm(); }
96
97 std::string getTypeName(TypeIndex TI) override {
98 std::string TypeName;
99 if (!TI.isNoneType()) {
100 if (TI.isSimple())
101 TypeName = std::string(TypeIndex::simpleTypeName(TI));
102 else
103 TypeName = std::string(TypeTable.getTypeName(Index: TI));
104 }
105 return TypeName;
106 }
107
108private:
109 MCStreamer *OS = nullptr;
110 TypeCollection &TypeTable;
111};
112} // namespace
113
114static CPUType mapArchToCVCPUType(Triple::ArchType Type) {
115 switch (Type) {
116 case Triple::ArchType::x86:
117 return CPUType::Pentium3;
118 case Triple::ArchType::x86_64:
119 return CPUType::X64;
120 case Triple::ArchType::thumb:
121 // LLVM currently doesn't support Windows CE and so thumb
122 // here is indiscriminately mapped to ARMNT specifically.
123 return CPUType::ARMNT;
124 case Triple::ArchType::aarch64:
125 return CPUType::ARM64;
126 case Triple::ArchType::mipsel:
127 return CPUType::MIPS;
128 case Triple::ArchType::UnknownArch:
129 return CPUType::Unknown;
130 default:
131 report_fatal_error(reason: "target architecture doesn't map to a CodeView CPUType");
132 }
133}
134
135CodeViewDebug::CodeViewDebug(AsmPrinter *AP)
136 : DebugHandlerBase(AP), OS(*Asm->OutStreamer), TypeTable(Allocator) {}
137
138StringRef CodeViewDebug::getFullFilepath(const DIFile *File) {
139 std::string &Filepath = FileToFilepathMap[File];
140 if (!Filepath.empty())
141 return Filepath;
142
143 StringRef Dir = File->getDirectory(), Filename = File->getFilename();
144
145 // If this is a Unix-style path, just use it as is. Don't try to canonicalize
146 // it textually because one of the path components could be a symlink.
147 if (Dir.starts_with(Prefix: "/") || Filename.starts_with(Prefix: "/")) {
148 if (llvm::sys::path::is_absolute(path: Filename, style: llvm::sys::path::Style::posix))
149 return Filename;
150 Filepath = std::string(Dir);
151 if (Dir.back() != '/')
152 Filepath += '/';
153 Filepath += Filename;
154 return Filepath;
155 }
156
157 // Clang emits directory and relative filename info into the IR, but CodeView
158 // operates on full paths. We could change Clang to emit full paths too, but
159 // that would increase the IR size and probably not needed for other users.
160 // For now, just concatenate and canonicalize the path here.
161 if (Filename.find(C: ':') == 1)
162 Filepath = std::string(Filename);
163 else
164 Filepath = (Dir + "\\" + Filename).str();
165
166 // Canonicalize the path. We have to do it textually because we may no longer
167 // have access the file in the filesystem.
168 // First, replace all slashes with backslashes.
169 llvm::replace(Range&: Filepath, OldValue: '/', NewValue: '\\');
170
171 // Remove all "\.\" with "\".
172 size_t Cursor = 0;
173 while ((Cursor = Filepath.find(s: "\\.\\", pos: Cursor)) != std::string::npos)
174 Filepath.erase(pos: Cursor, n: 2);
175
176 // Replace all "\XXX\..\" with "\". Don't try too hard though as the original
177 // path should be well-formatted, e.g. start with a drive letter, etc.
178 Cursor = 0;
179 while ((Cursor = Filepath.find(s: "\\..\\", pos: Cursor)) != std::string::npos) {
180 // Something's wrong if the path starts with "\..\", abort.
181 if (Cursor == 0)
182 break;
183
184 size_t PrevSlash = Filepath.rfind(c: '\\', pos: Cursor - 1);
185 if (PrevSlash == std::string::npos)
186 // Something's wrong, abort.
187 break;
188
189 Filepath.erase(pos: PrevSlash, n: Cursor + 3 - PrevSlash);
190 // The next ".." might be following the one we've just erased.
191 Cursor = PrevSlash;
192 }
193
194 // Remove all duplicate backslashes.
195 Cursor = 0;
196 while ((Cursor = Filepath.find(s: "\\\\", pos: Cursor)) != std::string::npos)
197 Filepath.erase(pos: Cursor, n: 1);
198
199 return Filepath;
200}
201
202unsigned CodeViewDebug::maybeRecordFile(const DIFile *F) {
203 StringRef FullPath = getFullFilepath(File: F);
204 unsigned NextId = FileIdMap.size() + 1;
205 auto Insertion = FileIdMap.insert(KV: std::make_pair(x&: FullPath, y&: NextId));
206 if (Insertion.second) {
207 // We have to compute the full filepath and emit a .cv_file directive.
208 ArrayRef<uint8_t> ChecksumAsBytes;
209 FileChecksumKind CSKind = FileChecksumKind::None;
210 if (F->getChecksum()) {
211 std::string Checksum = fromHex(Input: F->getChecksum()->Value);
212 void *CKMem = OS.getContext().allocate(Size: Checksum.size(), Align: 1);
213 memcpy(dest: CKMem, src: Checksum.data(), n: Checksum.size());
214 ChecksumAsBytes = ArrayRef<uint8_t>(
215 reinterpret_cast<const uint8_t *>(CKMem), Checksum.size());
216 switch (F->getChecksum()->Kind) {
217 case DIFile::CSK_MD5:
218 CSKind = FileChecksumKind::MD5;
219 break;
220 case DIFile::CSK_SHA1:
221 CSKind = FileChecksumKind::SHA1;
222 break;
223 case DIFile::CSK_SHA256:
224 CSKind = FileChecksumKind::SHA256;
225 break;
226 }
227 }
228 bool Success = OS.emitCVFileDirective(FileNo: NextId, Filename: FullPath, Checksum: ChecksumAsBytes,
229 ChecksumKind: static_cast<unsigned>(CSKind));
230 (void)Success;
231 assert(Success && ".cv_file directive failed");
232 }
233 return Insertion.first->second;
234}
235
236CodeViewDebug::InlineSite &
237CodeViewDebug::getInlineSite(const DILocation *InlinedAt,
238 const DISubprogram *Inlinee) {
239 auto SiteInsertion = CurFn->InlineSites.try_emplace(k: InlinedAt);
240 InlineSite *Site = &SiteInsertion.first->second;
241 if (SiteInsertion.second) {
242 unsigned ParentFuncId = CurFn->FuncId;
243 if (const DILocation *OuterIA = InlinedAt->getInlinedAt())
244 ParentFuncId =
245 getInlineSite(InlinedAt: OuterIA, Inlinee: InlinedAt->getScope()->getSubprogram())
246 .SiteFuncId;
247
248 Site->SiteFuncId = NextFuncId++;
249 OS.emitCVInlineSiteIdDirective(
250 FunctionId: Site->SiteFuncId, IAFunc: ParentFuncId, IAFile: maybeRecordFile(F: InlinedAt->getFile()),
251 IALine: InlinedAt->getLine(), IACol: InlinedAt->getColumn(), Loc: SMLoc());
252 Site->Inlinee = Inlinee;
253 InlinedSubprograms.insert(X: Inlinee);
254 auto InlineeIdx = getFuncIdForSubprogram(SP: Inlinee);
255
256 if (InlinedAt->getInlinedAt() == nullptr)
257 CurFn->Inlinees.insert(V: InlineeIdx);
258 }
259 return *Site;
260}
261
262static StringRef getPrettyScopeName(const DIScope *Scope) {
263 StringRef ScopeName = Scope->getName();
264 if (!ScopeName.empty())
265 return ScopeName;
266
267 switch (Scope->getTag()) {
268 case dwarf::DW_TAG_enumeration_type:
269 case dwarf::DW_TAG_class_type:
270 case dwarf::DW_TAG_structure_type:
271 case dwarf::DW_TAG_union_type:
272 return "<unnamed-tag>";
273 case dwarf::DW_TAG_namespace:
274 return "`anonymous namespace'";
275 default:
276 return StringRef();
277 }
278}
279
280const DISubprogram *CodeViewDebug::collectParentScopeNames(
281 const DIScope *Scope, SmallVectorImpl<StringRef> &QualifiedNameComponents) {
282 const DISubprogram *ClosestSubprogram = nullptr;
283 while (Scope != nullptr) {
284 if (ClosestSubprogram == nullptr)
285 ClosestSubprogram = dyn_cast<DISubprogram>(Val: Scope);
286
287 // If a type appears in a scope chain, make sure it gets emitted. The
288 // frontend will be responsible for deciding if this should be a forward
289 // declaration or a complete type.
290 if (const auto *Ty = dyn_cast<DICompositeType>(Val: Scope))
291 DeferredCompleteTypes.push_back(Elt: Ty);
292
293 StringRef ScopeName = getPrettyScopeName(Scope);
294 if (!ScopeName.empty())
295 QualifiedNameComponents.push_back(Elt: ScopeName);
296 Scope = Scope->getScope();
297 }
298 return ClosestSubprogram;
299}
300
301static std::string formatNestedName(ArrayRef<StringRef> QualifiedNameComponents,
302 StringRef TypeName) {
303 std::string FullyQualifiedName;
304 for (StringRef QualifiedNameComponent :
305 llvm::reverse(C&: QualifiedNameComponents)) {
306 FullyQualifiedName.append(str: std::string(QualifiedNameComponent));
307 FullyQualifiedName.append(s: "::");
308 }
309 FullyQualifiedName.append(str: std::string(TypeName));
310 return FullyQualifiedName;
311}
312
313struct CodeViewDebug::TypeLoweringScope {
314 TypeLoweringScope(CodeViewDebug &CVD) : CVD(CVD) { ++CVD.TypeEmissionLevel; }
315 ~TypeLoweringScope() {
316 // Don't decrement TypeEmissionLevel until after emitting deferred types, so
317 // inner TypeLoweringScopes don't attempt to emit deferred types.
318 if (CVD.TypeEmissionLevel == 1)
319 CVD.emitDeferredCompleteTypes();
320 --CVD.TypeEmissionLevel;
321 }
322 CodeViewDebug &CVD;
323};
324
325std::string CodeViewDebug::getFullyQualifiedName(const DIScope *Scope,
326 StringRef Name) {
327 // Ensure types in the scope chain are emitted as soon as possible.
328 // This can create otherwise a situation where S_UDTs are emitted while
329 // looping in emitDebugInfoForUDTs.
330 TypeLoweringScope S(*this);
331 SmallVector<StringRef, 5> QualifiedNameComponents;
332 collectParentScopeNames(Scope, QualifiedNameComponents);
333 return formatNestedName(QualifiedNameComponents, TypeName: Name);
334}
335
336std::string CodeViewDebug::getFullyQualifiedName(const DIScope *Ty) {
337 const DIScope *Scope = Ty->getScope();
338 return getFullyQualifiedName(Scope, Name: getPrettyScopeName(Scope: Ty));
339}
340
341TypeIndex CodeViewDebug::getScopeIndex(const DIScope *Scope) {
342 // No scope means global scope and that uses the zero index.
343 //
344 // We also use zero index when the scope is a DISubprogram
345 // to suppress the emission of LF_STRING_ID for the function,
346 // which can trigger a link-time error with the linker in
347 // VS2019 version 16.11.2 or newer.
348 // Note, however, skipping the debug info emission for the DISubprogram
349 // is a temporary fix. The root issue here is that we need to figure out
350 // the proper way to encode a function nested in another function
351 // (as introduced by the Fortran 'contains' keyword) in CodeView.
352 if (!Scope || isa<DIFile>(Val: Scope) || isa<DISubprogram>(Val: Scope))
353 return TypeIndex();
354
355 assert(!isa<DIType>(Scope) && "shouldn't make a namespace scope for a type");
356
357 // Check if we've already translated this scope.
358 auto I = TypeIndices.find(Val: {Scope, nullptr});
359 if (I != TypeIndices.end())
360 return I->second;
361
362 // Build the fully qualified name of the scope.
363 std::string ScopeName = getFullyQualifiedName(Ty: Scope);
364 StringIdRecord SID(TypeIndex(), ScopeName);
365 auto TI = TypeTable.writeLeafType(Record&: SID);
366 return recordTypeIndexForDINode(Node: Scope, TI);
367}
368
369static StringRef removeTemplateArgs(StringRef Name) {
370 // Remove template args from the display name. Assume that the template args
371 // are the last thing in the name.
372 if (Name.empty() || Name.back() != '>')
373 return Name;
374
375 int OpenBrackets = 0;
376 for (int i = Name.size() - 1; i >= 0; --i) {
377 if (Name[i] == '>')
378 ++OpenBrackets;
379 else if (Name[i] == '<') {
380 --OpenBrackets;
381 if (OpenBrackets == 0)
382 return Name.substr(Start: 0, N: i);
383 }
384 }
385 return Name;
386}
387
388TypeIndex CodeViewDebug::getFuncIdForSubprogram(const DISubprogram *SP) {
389 assert(SP);
390
391 // Check if we've already translated this subprogram.
392 auto I = TypeIndices.find(Val: {SP, nullptr});
393 if (I != TypeIndices.end())
394 return I->second;
395
396 // The display name includes function template arguments. Drop them to match
397 // MSVC. We need to have the template arguments in the DISubprogram name
398 // because they are used in other symbol records, such as S_GPROC32_IDs.
399 StringRef DisplayName = removeTemplateArgs(Name: SP->getName());
400
401 const DIScope *Scope = SP->getScope();
402 TypeIndex TI;
403 if (const auto *Class = dyn_cast_or_null<DICompositeType>(Val: Scope)) {
404 // If the scope is a DICompositeType, then this must be a method. Member
405 // function types take some special handling, and require access to the
406 // subprogram.
407 TypeIndex ClassType = getTypeIndex(Ty: Class);
408 MemberFuncIdRecord MFuncId(ClassType, getMemberFunctionType(SP, Class),
409 DisplayName);
410 TI = TypeTable.writeLeafType(Record&: MFuncId);
411 } else {
412 // Otherwise, this must be a free function.
413 TypeIndex ParentScope = getScopeIndex(Scope);
414 FuncIdRecord FuncId(ParentScope, getTypeIndex(Ty: SP->getType()), DisplayName);
415 TI = TypeTable.writeLeafType(Record&: FuncId);
416 }
417
418 return recordTypeIndexForDINode(Node: SP, TI);
419}
420
421static bool isNonTrivial(const DICompositeType *DCTy) {
422 return ((DCTy->getFlags() & DINode::FlagNonTrivial) == DINode::FlagNonTrivial);
423}
424
425static FunctionOptions
426getFunctionOptions(const DISubroutineType *Ty,
427 const DICompositeType *ClassTy = nullptr,
428 StringRef SPName = StringRef("")) {
429 FunctionOptions FO = FunctionOptions::None;
430 const DIType *ReturnTy = nullptr;
431 if (auto TypeArray = Ty->getTypeArray()) {
432 if (TypeArray.size())
433 ReturnTy = TypeArray[0];
434 }
435
436 // Add CxxReturnUdt option to functions that return nontrivial record types
437 // or methods that return record types.
438 if (auto *ReturnDCTy = dyn_cast_or_null<DICompositeType>(Val: ReturnTy))
439 if (isNonTrivial(DCTy: ReturnDCTy) || ClassTy)
440 FO |= FunctionOptions::CxxReturnUdt;
441
442 // DISubroutineType is unnamed. Use DISubprogram's i.e. SPName in comparison.
443 if (ClassTy && isNonTrivial(DCTy: ClassTy) && SPName == ClassTy->getName()) {
444 FO |= FunctionOptions::Constructor;
445
446 // TODO: put the FunctionOptions::ConstructorWithVirtualBases flag.
447
448 }
449 return FO;
450}
451
452TypeIndex CodeViewDebug::getMemberFunctionType(const DISubprogram *SP,
453 const DICompositeType *Class) {
454 // Always use the method declaration as the key for the function type. The
455 // method declaration contains the this adjustment.
456 if (SP->getDeclaration())
457 SP = SP->getDeclaration();
458 assert(!SP->getDeclaration() && "should use declaration as key");
459
460 // Key the MemberFunctionRecord into the map as {SP, Class}. It won't collide
461 // with the MemberFuncIdRecord, which is keyed in as {SP, nullptr}.
462 auto I = TypeIndices.find(Val: {SP, Class});
463 if (I != TypeIndices.end())
464 return I->second;
465
466 // Make sure complete type info for the class is emitted *after* the member
467 // function type, as the complete class type is likely to reference this
468 // member function type.
469 TypeLoweringScope S(*this);
470 const bool IsStaticMethod = (SP->getFlags() & DINode::FlagStaticMember) != 0;
471
472 FunctionOptions FO = getFunctionOptions(Ty: SP->getType(), ClassTy: Class, SPName: SP->getName());
473 TypeIndex TI = lowerTypeMemberFunction(
474 Ty: SP->getType(), ClassTy: Class, ThisAdjustment: SP->getThisAdjustment(), IsStaticMethod, FO);
475 return recordTypeIndexForDINode(Node: SP, TI, ClassTy: Class);
476}
477
478TypeIndex CodeViewDebug::recordTypeIndexForDINode(const DINode *Node,
479 TypeIndex TI,
480 const DIType *ClassTy) {
481 auto InsertResult = TypeIndices.insert(KV: {{Node, ClassTy}, TI});
482 (void)InsertResult;
483 assert(InsertResult.second && "DINode was already assigned a type index");
484 return TI;
485}
486
487unsigned CodeViewDebug::getPointerSizeInBytes() {
488 return MMI->getModule()->getDataLayout().getPointerSizeInBits() / 8;
489}
490
491void CodeViewDebug::recordLocalVariable(LocalVariable &&Var,
492 const LexicalScope *LS) {
493 if (const DILocation *InlinedAt = LS->getInlinedAt()) {
494 // This variable was inlined. Associate it with the InlineSite.
495 const DISubprogram *Inlinee = Var.DIVar->getScope()->getSubprogram();
496 InlineSite &Site = getInlineSite(InlinedAt, Inlinee);
497 Site.InlinedLocals.emplace_back(Args: std::move(Var));
498 } else {
499 // This variable goes into the corresponding lexical scope.
500 ScopeVariables[LS].emplace_back(Args: std::move(Var));
501 }
502}
503
504static void addLocIfNotPresent(SmallVectorImpl<const DILocation *> &Locs,
505 const DILocation *Loc) {
506 if (!llvm::is_contained(Range&: Locs, Element: Loc))
507 Locs.push_back(Elt: Loc);
508}
509
510void CodeViewDebug::maybeRecordLocation(const DebugLoc &DL,
511 const MachineFunction *MF) {
512 // Skip this instruction if it has the same location as the previous one.
513 if (!DL || DL == PrevInstLoc)
514 return;
515
516 const DIScope *Scope = DL->getScope();
517 if (!Scope)
518 return;
519
520 // Skip this line if it is longer than the maximum we can record.
521 LineInfo LI(DL.getLine(), DL.getLine(), /*IsStatement=*/true);
522 if (LI.getStartLine() != DL.getLine() || LI.isAlwaysStepInto() ||
523 LI.isNeverStepInto())
524 return;
525
526 ColumnInfo CI(DL.getCol(), /*EndColumn=*/0);
527 if (CI.getStartColumn() != DL.getCol())
528 return;
529
530 if (!CurFn->HaveLineInfo)
531 CurFn->HaveLineInfo = true;
532 unsigned FileId = 0;
533 if (PrevInstLoc.get() && PrevInstLoc->getFile() == DL->getFile())
534 FileId = CurFn->LastFileId;
535 else
536 FileId = CurFn->LastFileId = maybeRecordFile(F: DL->getFile());
537 PrevInstLoc = DL;
538
539 unsigned FuncId = CurFn->FuncId;
540 if (const DILocation *SiteLoc = DL->getInlinedAt()) {
541 const DILocation *Loc = DL.get();
542
543 // If this location was actually inlined from somewhere else, give it the ID
544 // of the inline call site.
545 FuncId =
546 getInlineSite(InlinedAt: SiteLoc, Inlinee: Loc->getScope()->getSubprogram()).SiteFuncId;
547
548 // Ensure we have links in the tree of inline call sites.
549 bool FirstLoc = true;
550 while ((SiteLoc = Loc->getInlinedAt())) {
551 InlineSite &Site =
552 getInlineSite(InlinedAt: SiteLoc, Inlinee: Loc->getScope()->getSubprogram());
553 if (!FirstLoc)
554 addLocIfNotPresent(Locs&: Site.ChildSites, Loc);
555 FirstLoc = false;
556 Loc = SiteLoc;
557 }
558 addLocIfNotPresent(Locs&: CurFn->ChildSites, Loc);
559 }
560
561 OS.emitCVLocDirective(FunctionId: FuncId, FileNo: FileId, Line: DL.getLine(), Column: DL.getCol(),
562 /*PrologueEnd=*/false, /*IsStmt=*/false,
563 FileName: DL->getFilename(), Loc: SMLoc());
564}
565
566void CodeViewDebug::emitCodeViewMagicVersion() {
567 OS.emitValueToAlignment(Alignment: Align(4));
568 OS.AddComment(T: "Debug section magic");
569 OS.emitInt32(Value: COFF::DEBUG_SECTION_MAGIC);
570}
571
572static SourceLanguage MapDWLangToCVLang(unsigned DWLang) {
573 switch (DWLang) {
574 case dwarf::DW_LANG_C:
575 case dwarf::DW_LANG_C89:
576 case dwarf::DW_LANG_C99:
577 case dwarf::DW_LANG_C11:
578 return SourceLanguage::C;
579 case dwarf::DW_LANG_C_plus_plus:
580 case dwarf::DW_LANG_C_plus_plus_03:
581 case dwarf::DW_LANG_C_plus_plus_11:
582 case dwarf::DW_LANG_C_plus_plus_14:
583 return SourceLanguage::Cpp;
584 case dwarf::DW_LANG_Fortran77:
585 case dwarf::DW_LANG_Fortran90:
586 case dwarf::DW_LANG_Fortran95:
587 case dwarf::DW_LANG_Fortran03:
588 case dwarf::DW_LANG_Fortran08:
589 return SourceLanguage::Fortran;
590 case dwarf::DW_LANG_Pascal83:
591 return SourceLanguage::Pascal;
592 case dwarf::DW_LANG_Cobol74:
593 case dwarf::DW_LANG_Cobol85:
594 return SourceLanguage::Cobol;
595 case dwarf::DW_LANG_Java:
596 return SourceLanguage::Java;
597 case dwarf::DW_LANG_D:
598 return SourceLanguage::D;
599 case dwarf::DW_LANG_Swift:
600 return SourceLanguage::Swift;
601 case dwarf::DW_LANG_Rust:
602 return SourceLanguage::Rust;
603 case dwarf::DW_LANG_ObjC:
604 return SourceLanguage::ObjC;
605 case dwarf::DW_LANG_ObjC_plus_plus:
606 return SourceLanguage::ObjCpp;
607 default:
608 // There's no CodeView representation for this language, and CV doesn't
609 // have an "unknown" option for the language field, so we'll use MASM,
610 // as it's very low level.
611 return SourceLanguage::Masm;
612 }
613}
614
615void CodeViewDebug::beginModule(Module *M) {
616 // If COFF debug section is not available, skip any debug info related stuff.
617 if (!Asm->getObjFileLowering().getCOFFDebugSymbolsSection()) {
618 Asm = nullptr;
619 return;
620 }
621
622 CompilerInfoAsm = Asm;
623 TheCPU = mapArchToCVCPUType(Type: M->getTargetTriple().getArch());
624
625 // Get the current source language.
626 const MDNode *Node;
627 if (Asm->hasDebugInfo()) {
628 Node = *M->debug_compile_units_begin();
629 } else {
630 // When emitting only compiler information, we may have only NoDebug CUs,
631 // which would be skipped by debug_compile_units_begin.
632 NamedMDNode *CUs = MMI->getModule()->getNamedMetadata(Name: "llvm.dbg.cu");
633 Node = *CUs->operands().begin();
634 }
635 const auto *CU = cast<DICompileUnit>(Val: Node);
636
637 CurrentSourceLanguage = MapDWLangToCVLang(DWLang: CU->getSourceLanguage());
638 if (!M->getCodeViewFlag() ||
639 CU->getEmissionKind() == DICompileUnit::NoDebug) {
640 Asm = nullptr;
641 return;
642 }
643
644 collectGlobalVariableInfo();
645
646 // Check if we should emit type record hashes.
647 ConstantInt *GH =
648 mdconst::extract_or_null<ConstantInt>(MD: M->getModuleFlag(Key: "CodeViewGHash"));
649 EmitDebugGlobalHashes = GH && !GH->isZero();
650}
651
652void CodeViewDebug::endModule() {
653 if (!CompilerInfoAsm)
654 return;
655
656 // The COFF .debug$S section consists of several subsections, each starting
657 // with a 4-byte control code (e.g. 0xF1, 0xF2, etc) and then a 4-byte length
658 // of the payload followed by the payload itself. The subsections are 4-byte
659 // aligned.
660
661 // Use the generic .debug$S section, and make a subsection for all the inlined
662 // subprograms.
663 switchToDebugSectionForSymbol(GVSym: nullptr);
664
665 MCSymbol *CompilerInfo = beginCVSubsection(Kind: DebugSubsectionKind::Symbols);
666 emitObjName();
667 emitCompilerInformation();
668 endCVSubsection(EndLabel: CompilerInfo);
669 if (!Asm)
670 return;
671
672 emitSecureHotPatchInformation();
673
674 emitInlineeLinesSubsection();
675
676 // Emit per-function debug information.
677 for (auto &P : FnDebugInfo)
678 if (!P.first->isDeclarationForLinker())
679 emitDebugInfoForFunction(GV: P.first, FI&: *P.second);
680
681 // Get types used by globals without emitting anything.
682 // This is meant to collect all static const data members so they can be
683 // emitted as globals.
684 collectDebugInfoForGlobals();
685
686 // Emit retained types.
687 emitDebugInfoForRetainedTypes();
688
689 // Emit global variable debug information.
690 setCurrentSubprogram(nullptr);
691 emitDebugInfoForGlobals();
692
693 // Switch back to the generic .debug$S section after potentially processing
694 // comdat symbol sections.
695 switchToDebugSectionForSymbol(GVSym: nullptr);
696
697 // Emit UDT records for any types used by global variables.
698 if (!GlobalUDTs.empty()) {
699 MCSymbol *SymbolsEnd = beginCVSubsection(Kind: DebugSubsectionKind::Symbols);
700 emitDebugInfoForUDTs(UDTs: GlobalUDTs);
701 endCVSubsection(EndLabel: SymbolsEnd);
702 }
703
704 // This subsection holds a file index to offset in string table table.
705 OS.AddComment(T: "File index to string table offset subsection");
706 OS.emitCVFileChecksumsDirective();
707
708 // This subsection holds the string table.
709 OS.AddComment(T: "String table");
710 OS.emitCVStringTableDirective();
711
712 // Emit S_BUILDINFO, which points to LF_BUILDINFO. Put this in its own symbol
713 // subsection in the generic .debug$S section at the end. There is no
714 // particular reason for this ordering other than to match MSVC.
715 emitBuildInfo();
716
717 // Emit type information and hashes last, so that any types we translate while
718 // emitting function info are included.
719 emitTypeInformation();
720
721 if (EmitDebugGlobalHashes)
722 emitTypeGlobalHashes();
723
724 clear();
725}
726
727static void
728emitNullTerminatedSymbolName(MCStreamer &OS, StringRef S,
729 unsigned MaxFixedRecordLength = 0xF00) {
730 // The maximum CV record length is 0xFF00. Most of the strings we emit appear
731 // after a fixed length portion of the record. The fixed length portion should
732 // always be less than 0xF00 (3840) bytes, so truncate the string so that the
733 // overall record size is less than the maximum allowed.
734 SmallString<32> NullTerminatedString(
735 S.take_front(N: MaxRecordLength - MaxFixedRecordLength - 1));
736 NullTerminatedString.push_back(Elt: '\0');
737 OS.emitBytes(Data: NullTerminatedString);
738}
739
740void CodeViewDebug::emitTypeInformation() {
741 if (TypeTable.empty())
742 return;
743
744 // Start the .debug$T or .debug$P section with 0x4.
745 OS.switchSection(Section: Asm->getObjFileLowering().getCOFFDebugTypesSection());
746 emitCodeViewMagicVersion();
747
748 TypeTableCollection Table(TypeTable.records());
749 TypeVisitorCallbackPipeline Pipeline;
750
751 // To emit type record using Codeview MCStreamer adapter
752 CVMCAdapter CVMCOS(OS, Table);
753 TypeRecordMapping typeMapping(CVMCOS);
754 Pipeline.addCallbackToPipeline(Callbacks&: typeMapping);
755
756 std::optional<TypeIndex> B = Table.getFirst();
757 while (B) {
758 // This will fail if the record data is invalid.
759 CVType Record = Table.getType(Index: *B);
760
761 Error E = codeview::visitTypeRecord(Record, Index: *B, Callbacks&: Pipeline);
762
763 if (E) {
764 logAllUnhandledErrors(E: std::move(E), OS&: errs(), ErrorBanner: "error: ");
765 llvm_unreachable("produced malformed type record");
766 }
767
768 B = Table.getNext(Prev: *B);
769 }
770}
771
772void CodeViewDebug::emitTypeGlobalHashes() {
773 if (TypeTable.empty())
774 return;
775
776 // Start the .debug$H section with the version and hash algorithm, currently
777 // hardcoded to version 0, SHA1.
778 OS.switchSection(Section: Asm->getObjFileLowering().getCOFFGlobalTypeHashesSection());
779
780 OS.emitValueToAlignment(Alignment: Align(4));
781 OS.AddComment(T: "Magic");
782 OS.emitInt32(Value: COFF::DEBUG_HASHES_SECTION_MAGIC);
783 OS.AddComment(T: "Section Version");
784 OS.emitInt16(Value: 0);
785 OS.AddComment(T: "Hash Algorithm");
786 OS.emitInt16(Value: uint16_t(GlobalTypeHashAlg::BLAKE3));
787
788 TypeIndex TI(TypeIndex::FirstNonSimpleIndex);
789 for (const auto &GHR : TypeTable.hashes()) {
790 if (OS.isVerboseAsm()) {
791 // Emit an EOL-comment describing which TypeIndex this hash corresponds
792 // to, as well as the stringified SHA1 hash.
793 SmallString<32> Comment;
794 raw_svector_ostream CommentOS(Comment);
795 CommentOS << formatv(Fmt: "{0:X+} [{1}]", Vals: TI.getIndex(), Vals: GHR);
796 OS.AddComment(T: Comment);
797 ++TI;
798 }
799 assert(GHR.Hash.size() == 8);
800 StringRef S(reinterpret_cast<const char *>(GHR.Hash.data()),
801 GHR.Hash.size());
802 OS.emitBinaryData(Data: S);
803 }
804}
805
806void CodeViewDebug::emitObjName() {
807 MCSymbol *CompilerEnd = beginSymbolRecord(Kind: SymbolKind::S_OBJNAME);
808
809 StringRef PathRef(CompilerInfoAsm->TM.Options.ObjectFilenameForDebug);
810 llvm::SmallString<256> PathStore(PathRef);
811
812 if (PathRef.empty() || PathRef == "-") {
813 // Don't emit the filename if we're writing to stdout or to /dev/null.
814 PathRef = {};
815 } else {
816 PathRef = PathStore;
817 }
818
819 OS.AddComment(T: "Signature");
820 OS.emitIntValue(Value: 0, Size: 4);
821
822 OS.AddComment(T: "Object name");
823 emitNullTerminatedSymbolName(OS, S: PathRef);
824
825 endSymbolRecord(SymEnd: CompilerEnd);
826}
827
828void CodeViewDebug::emitSecureHotPatchInformation() {
829 MCSymbol *hotPatchInfo = nullptr;
830
831 for (const auto &F : MMI->getModule()->functions()) {
832 if (!F.isDeclarationForLinker() &&
833 F.hasFnAttribute(Kind: "marked_for_windows_hot_patching")) {
834 if (hotPatchInfo == nullptr)
835 hotPatchInfo = beginCVSubsection(Kind: DebugSubsectionKind::Symbols);
836 MCSymbol *HotPatchEnd = beginSymbolRecord(Kind: SymbolKind::S_HOTPATCHFUNC);
837 auto *SP = F.getSubprogram();
838 OS.AddComment(T: "Function");
839 OS.emitInt32(Value: getFuncIdForSubprogram(SP).getIndex());
840 OS.AddComment(T: "Name");
841 emitNullTerminatedSymbolName(OS, S: F.getName());
842 endSymbolRecord(SymEnd: HotPatchEnd);
843 }
844 }
845
846 if (hotPatchInfo != nullptr)
847 endCVSubsection(EndLabel: hotPatchInfo);
848}
849
850namespace {
851struct Version {
852 int Part[4];
853};
854} // end anonymous namespace
855
856// Takes a StringRef like "clang 4.0.0.0 (other nonsense 123)" and parses out
857// the version number.
858static Version parseVersion(StringRef Name) {
859 Version V = {.Part: {0}};
860 int N = 0;
861 for (const char C : Name) {
862 if (isdigit(C)) {
863 V.Part[N] *= 10;
864 V.Part[N] += C - '0';
865 V.Part[N] =
866 std::min<int>(a: V.Part[N], b: std::numeric_limits<uint16_t>::max());
867 } else if (C == '.') {
868 ++N;
869 if (N >= 4)
870 return V;
871 } else if (N > 0)
872 return V;
873 }
874 return V;
875}
876
877void CodeViewDebug::emitCompilerInformation() {
878 MCSymbol *CompilerEnd = beginSymbolRecord(Kind: SymbolKind::S_COMPILE3);
879 uint32_t Flags = 0;
880
881 // The low byte of the flags indicates the source language.
882 Flags = CurrentSourceLanguage;
883 // TODO: Figure out which other flags need to be set.
884 if (MMI->getModule()->getProfileSummary(/*IsCS*/ false) != nullptr) {
885 Flags |= static_cast<uint32_t>(CompileSym3Flags::PGO);
886 }
887 using ArchType = llvm::Triple::ArchType;
888 ArchType Arch = MMI->getModule()->getTargetTriple().getArch();
889 if (CompilerInfoAsm->TM.Options.Hotpatch || Arch == ArchType::thumb ||
890 Arch == ArchType::aarch64) {
891 Flags |= static_cast<uint32_t>(CompileSym3Flags::HotPatch);
892 }
893
894 OS.AddComment(T: "Flags and language");
895 OS.emitInt32(Value: Flags);
896
897 OS.AddComment(T: "CPUType");
898 OS.emitInt16(Value: static_cast<uint64_t>(TheCPU));
899
900 NamedMDNode *CUs = MMI->getModule()->getNamedMetadata(Name: "llvm.dbg.cu");
901 const MDNode *Node = *CUs->operands().begin();
902 const auto *CU = cast<DICompileUnit>(Val: Node);
903
904 StringRef CompilerVersion = CU->getProducer();
905 Version FrontVer = parseVersion(Name: CompilerVersion);
906 OS.AddComment(T: "Frontend version");
907 for (int N : FrontVer.Part) {
908 OS.emitInt16(Value: N);
909 }
910
911 // Some Microsoft tools, like Binscope, expect a backend version number of at
912 // least 8.something, so we'll coerce the LLVM version into a form that
913 // guarantees it'll be big enough without really lying about the version.
914 int Major = 1000 * LLVM_VERSION_MAJOR +
915 10 * LLVM_VERSION_MINOR +
916 LLVM_VERSION_PATCH;
917 // Clamp it for builds that use unusually large version numbers.
918 Major = std::min<int>(a: Major, b: std::numeric_limits<uint16_t>::max());
919 Version BackVer = {.Part: { Major, 0, 0, 0 }};
920 OS.AddComment(T: "Backend version");
921 for (int N : BackVer.Part)
922 OS.emitInt16(Value: N);
923
924 OS.AddComment(T: "Null-terminated compiler version string");
925 emitNullTerminatedSymbolName(OS, S: CompilerVersion);
926
927 endSymbolRecord(SymEnd: CompilerEnd);
928}
929
930static TypeIndex getStringIdTypeIdx(GlobalTypeTableBuilder &TypeTable,
931 StringRef S) {
932 StringIdRecord SIR(TypeIndex(0x0), S);
933 return TypeTable.writeLeafType(Record&: SIR);
934}
935
936void CodeViewDebug::emitBuildInfo() {
937 // First, make LF_BUILDINFO. It's a sequence of strings with various bits of
938 // build info. The known prefix is:
939 // - Absolute path of current directory
940 // - Compiler path
941 // - Main source file path, relative to CWD or absolute
942 // - Type server PDB file
943 // - Canonical compiler command line
944 // If frontend and backend compilation are separated (think llc or LTO), it's
945 // not clear if the compiler path should refer to the executable for the
946 // frontend or the backend. Leave it blank for now.
947 TypeIndex BuildInfoArgs[BuildInfoRecord::MaxArgs] = {};
948 NamedMDNode *CUs = MMI->getModule()->getNamedMetadata(Name: "llvm.dbg.cu");
949 const MDNode *Node = *CUs->operands().begin(); // FIXME: Multiple CUs.
950 const auto *CU = cast<DICompileUnit>(Val: Node);
951 const DIFile *MainSourceFile = CU->getFile();
952 BuildInfoArgs[BuildInfoRecord::CurrentDirectory] =
953 getStringIdTypeIdx(TypeTable, S: MainSourceFile->getDirectory());
954 BuildInfoArgs[BuildInfoRecord::SourceFile] =
955 getStringIdTypeIdx(TypeTable, S: MainSourceFile->getFilename());
956 // FIXME: PDB is intentionally blank unless we implement /Zi type servers.
957 BuildInfoArgs[BuildInfoRecord::TypeServerPDB] =
958 getStringIdTypeIdx(TypeTable, S: "");
959 BuildInfoArgs[BuildInfoRecord::BuildTool] =
960 getStringIdTypeIdx(TypeTable, S: Asm->TM.Options.MCOptions.Argv0);
961 BuildInfoArgs[BuildInfoRecord::CommandLine] = getStringIdTypeIdx(
962 TypeTable, S: Asm->TM.Options.MCOptions.CommandlineArgs);
963
964 BuildInfoRecord BIR(BuildInfoArgs);
965 TypeIndex BuildInfoIndex = TypeTable.writeLeafType(Record&: BIR);
966
967 // Make a new .debug$S subsection for the S_BUILDINFO record, which points
968 // from the module symbols into the type stream.
969 MCSymbol *BISubsecEnd = beginCVSubsection(Kind: DebugSubsectionKind::Symbols);
970 MCSymbol *BIEnd = beginSymbolRecord(Kind: SymbolKind::S_BUILDINFO);
971 OS.AddComment(T: "LF_BUILDINFO index");
972 OS.emitInt32(Value: BuildInfoIndex.getIndex());
973 endSymbolRecord(SymEnd: BIEnd);
974 endCVSubsection(EndLabel: BISubsecEnd);
975}
976
977void CodeViewDebug::emitInlineeLinesSubsection() {
978 if (InlinedSubprograms.empty())
979 return;
980
981 OS.AddComment(T: "Inlinee lines subsection");
982 MCSymbol *InlineEnd = beginCVSubsection(Kind: DebugSubsectionKind::InlineeLines);
983
984 // We emit the checksum info for files. This is used by debuggers to
985 // determine if a pdb matches the source before loading it. Visual Studio,
986 // for instance, will display a warning that the breakpoints are not valid if
987 // the pdb does not match the source.
988 OS.AddComment(T: "Inlinee lines signature");
989 OS.emitInt32(Value: unsigned(InlineeLinesSignature::Normal));
990
991 for (const DISubprogram *SP : InlinedSubprograms) {
992 assert(TypeIndices.count({SP, nullptr}));
993 TypeIndex InlineeIdx = TypeIndices[{SP, nullptr}];
994
995 OS.addBlankLine();
996 unsigned FileId = maybeRecordFile(F: SP->getFile());
997 OS.AddComment(T: "Inlined function " + SP->getName() + " starts at " +
998 SP->getFilename() + Twine(':') + Twine(SP->getLine()));
999 OS.addBlankLine();
1000 OS.AddComment(T: "Type index of inlined function");
1001 OS.emitInt32(Value: InlineeIdx.getIndex());
1002 OS.AddComment(T: "Offset into filechecksum table");
1003 OS.emitCVFileChecksumOffsetDirective(FileNo: FileId);
1004 OS.AddComment(T: "Starting line number");
1005 OS.emitInt32(Value: SP->getLine());
1006 }
1007
1008 endCVSubsection(EndLabel: InlineEnd);
1009}
1010
1011void CodeViewDebug::emitInlinedCallSite(const FunctionInfo &FI,
1012 const DILocation *InlinedAt,
1013 const InlineSite &Site) {
1014 assert(TypeIndices.count({Site.Inlinee, nullptr}));
1015 TypeIndex InlineeIdx = TypeIndices[{Site.Inlinee, nullptr}];
1016
1017 // SymbolRecord
1018 MCSymbol *InlineEnd = beginSymbolRecord(Kind: SymbolKind::S_INLINESITE);
1019
1020 OS.AddComment(T: "PtrParent");
1021 OS.emitInt32(Value: 0);
1022 OS.AddComment(T: "PtrEnd");
1023 OS.emitInt32(Value: 0);
1024 OS.AddComment(T: "Inlinee type index");
1025 OS.emitInt32(Value: InlineeIdx.getIndex());
1026
1027 unsigned FileId = maybeRecordFile(F: Site.Inlinee->getFile());
1028 unsigned StartLineNum = Site.Inlinee->getLine();
1029
1030 OS.emitCVInlineLinetableDirective(PrimaryFunctionId: Site.SiteFuncId, SourceFileId: FileId, SourceLineNum: StartLineNum,
1031 FnStartSym: FI.Begin, FnEndSym: FI.End);
1032
1033 endSymbolRecord(SymEnd: InlineEnd);
1034
1035 emitLocalVariableList(FI, Locals: Site.InlinedLocals);
1036
1037 // Recurse on child inlined call sites before closing the scope.
1038 for (const DILocation *ChildSite : Site.ChildSites) {
1039 auto I = FI.InlineSites.find(x: ChildSite);
1040 assert(I != FI.InlineSites.end() &&
1041 "child site not in function inline site map");
1042 emitInlinedCallSite(FI, InlinedAt: ChildSite, Site: I->second);
1043 }
1044
1045 // Close the scope.
1046 emitEndSymbolRecord(EndKind: SymbolKind::S_INLINESITE_END);
1047}
1048
1049void CodeViewDebug::switchToDebugSectionForSymbol(const MCSymbol *GVSym) {
1050 // If we have a symbol, it may be in a section that is COMDAT. If so, find the
1051 // comdat key. A section may be comdat because of -ffunction-sections or
1052 // because it is comdat in the IR.
1053 MCSectionCOFF *GVSec =
1054 GVSym ? dyn_cast<MCSectionCOFF>(Val: &GVSym->getSection()) : nullptr;
1055 const MCSymbol *KeySym = GVSec ? GVSec->getCOMDATSymbol() : nullptr;
1056
1057 MCSectionCOFF *DebugSec = cast<MCSectionCOFF>(
1058 Val: CompilerInfoAsm->getObjFileLowering().getCOFFDebugSymbolsSection());
1059 DebugSec = OS.getContext().getAssociativeCOFFSection(Sec: DebugSec, KeySym);
1060
1061 OS.switchSection(Section: DebugSec);
1062
1063 // Emit the magic version number if this is the first time we've switched to
1064 // this section.
1065 if (ComdatDebugSections.insert(V: DebugSec).second)
1066 emitCodeViewMagicVersion();
1067}
1068
1069// Emit an S_THUNK32/S_END symbol pair for a thunk routine.
1070// The only supported thunk ordinal is currently the standard type.
1071void CodeViewDebug::emitDebugInfoForThunk(const Function *GV,
1072 FunctionInfo &FI,
1073 const MCSymbol *Fn) {
1074 std::string FuncName =
1075 std::string(GlobalValue::dropLLVMManglingEscape(Name: GV->getName()));
1076 const ThunkOrdinal ordinal = ThunkOrdinal::Standard; // Only supported kind.
1077
1078 OS.AddComment(T: "Symbol subsection for " + Twine(FuncName));
1079 MCSymbol *SymbolsEnd = beginCVSubsection(Kind: DebugSubsectionKind::Symbols);
1080
1081 // Emit S_THUNK32
1082 MCSymbol *ThunkRecordEnd = beginSymbolRecord(Kind: SymbolKind::S_THUNK32);
1083 OS.AddComment(T: "PtrParent");
1084 OS.emitInt32(Value: 0);
1085 OS.AddComment(T: "PtrEnd");
1086 OS.emitInt32(Value: 0);
1087 OS.AddComment(T: "PtrNext");
1088 OS.emitInt32(Value: 0);
1089 OS.AddComment(T: "Thunk section relative address");
1090 OS.emitCOFFSecRel32(Symbol: Fn, /*Offset=*/0);
1091 OS.AddComment(T: "Thunk section index");
1092 OS.emitCOFFSectionIndex(Symbol: Fn);
1093 OS.AddComment(T: "Code size");
1094 OS.emitAbsoluteSymbolDiff(Hi: FI.End, Lo: Fn, Size: 2);
1095 OS.AddComment(T: "Ordinal");
1096 OS.emitInt8(Value: unsigned(ordinal));
1097 OS.AddComment(T: "Function name");
1098 emitNullTerminatedSymbolName(OS, S: FuncName);
1099 // Additional fields specific to the thunk ordinal would go here.
1100 endSymbolRecord(SymEnd: ThunkRecordEnd);
1101
1102 // Local variables/inlined routines are purposely omitted here. The point of
1103 // marking this as a thunk is so Visual Studio will NOT stop in this routine.
1104
1105 // Emit S_PROC_ID_END
1106 emitEndSymbolRecord(EndKind: SymbolKind::S_PROC_ID_END);
1107
1108 endCVSubsection(EndLabel: SymbolsEnd);
1109}
1110
1111void CodeViewDebug::emitDebugInfoForFunction(const Function *GV,
1112 FunctionInfo &FI) {
1113 // For each function there is a separate subsection which holds the PC to
1114 // file:line table.
1115 const MCSymbol *Fn = Asm->getSymbol(GV);
1116 assert(Fn);
1117
1118 // Switch to the to a comdat section, if appropriate.
1119 switchToDebugSectionForSymbol(GVSym: Fn);
1120
1121 std::string FuncName;
1122 auto *SP = GV->getSubprogram();
1123 assert(SP);
1124 setCurrentSubprogram(SP);
1125
1126 if (SP->isThunk()) {
1127 emitDebugInfoForThunk(GV, FI, Fn);
1128 return;
1129 }
1130
1131 // If we have a display name, build the fully qualified name by walking the
1132 // chain of scopes.
1133 if (!SP->getName().empty())
1134 FuncName = getFullyQualifiedName(Scope: SP->getScope(), Name: SP->getName());
1135
1136 // If our DISubprogram name is empty, use the mangled name.
1137 if (FuncName.empty())
1138 FuncName = std::string(GlobalValue::dropLLVMManglingEscape(Name: GV->getName()));
1139
1140 // Emit FPO data, but only on 32-bit x86. No other platforms use it.
1141 if (MMI->getModule()->getTargetTriple().getArch() == Triple::x86)
1142 OS.emitCVFPOData(ProcSym: Fn);
1143
1144 // Emit a symbol subsection, required by VS2012+ to find function boundaries.
1145 OS.AddComment(T: "Symbol subsection for " + Twine(FuncName));
1146 MCSymbol *SymbolsEnd = beginCVSubsection(Kind: DebugSubsectionKind::Symbols);
1147 {
1148 SymbolKind ProcKind = GV->hasLocalLinkage() ? SymbolKind::S_LPROC32_ID
1149 : SymbolKind::S_GPROC32_ID;
1150 MCSymbol *ProcRecordEnd = beginSymbolRecord(Kind: ProcKind);
1151
1152 // These fields are filled in by tools like CVPACK which run after the fact.
1153 OS.AddComment(T: "PtrParent");
1154 OS.emitInt32(Value: 0);
1155 OS.AddComment(T: "PtrEnd");
1156 OS.emitInt32(Value: 0);
1157 OS.AddComment(T: "PtrNext");
1158 OS.emitInt32(Value: 0);
1159 // This is the important bit that tells the debugger where the function
1160 // code is located and what's its size:
1161 OS.AddComment(T: "Code size");
1162 OS.emitAbsoluteSymbolDiff(Hi: FI.End, Lo: Fn, Size: 4);
1163 OS.AddComment(T: "Offset after prologue");
1164 OS.emitInt32(Value: 0);
1165 OS.AddComment(T: "Offset before epilogue");
1166 OS.emitInt32(Value: 0);
1167 OS.AddComment(T: "Function type index");
1168 OS.emitInt32(Value: getFuncIdForSubprogram(SP: GV->getSubprogram()).getIndex());
1169 OS.AddComment(T: "Function section relative address");
1170 OS.emitCOFFSecRel32(Symbol: Fn, /*Offset=*/0);
1171 OS.AddComment(T: "Function section index");
1172 OS.emitCOFFSectionIndex(Symbol: Fn);
1173 OS.AddComment(T: "Flags");
1174 ProcSymFlags ProcFlags = ProcSymFlags::HasOptimizedDebugInfo;
1175 if (FI.HasFramePointer)
1176 ProcFlags |= ProcSymFlags::HasFP;
1177 if (GV->hasFnAttribute(Kind: Attribute::NoReturn))
1178 ProcFlags |= ProcSymFlags::IsNoReturn;
1179 if (GV->hasFnAttribute(Kind: Attribute::NoInline))
1180 ProcFlags |= ProcSymFlags::IsNoInline;
1181 OS.emitInt8(Value: static_cast<uint8_t>(ProcFlags));
1182 // Emit the function display name as a null-terminated string.
1183 OS.AddComment(T: "Function name");
1184 // Truncate the name so we won't overflow the record length field.
1185 emitNullTerminatedSymbolName(OS, S: FuncName);
1186 endSymbolRecord(SymEnd: ProcRecordEnd);
1187
1188 MCSymbol *FrameProcEnd = beginSymbolRecord(Kind: SymbolKind::S_FRAMEPROC);
1189 // Subtract out the CSR size since MSVC excludes that and we include it.
1190 OS.AddComment(T: "FrameSize");
1191 OS.emitInt32(Value: FI.FrameSize - FI.CSRSize);
1192 OS.AddComment(T: "Padding");
1193 OS.emitInt32(Value: 0);
1194 OS.AddComment(T: "Offset of padding");
1195 OS.emitInt32(Value: 0);
1196 OS.AddComment(T: "Bytes of callee saved registers");
1197 OS.emitInt32(Value: FI.CSRSize);
1198 OS.AddComment(T: "Exception handler offset");
1199 OS.emitInt32(Value: 0);
1200 OS.AddComment(T: "Exception handler section");
1201 OS.emitInt16(Value: 0);
1202 OS.AddComment(T: "Flags (defines frame register)");
1203 OS.emitInt32(Value: uint32_t(FI.FrameProcOpts));
1204 endSymbolRecord(SymEnd: FrameProcEnd);
1205
1206 emitInlinees(Inlinees: FI.Inlinees);
1207 emitLocalVariableList(FI, Locals: FI.Locals);
1208 emitGlobalVariableList(Globals: FI.Globals);
1209 emitLexicalBlockList(Blocks: FI.ChildBlocks, FI);
1210
1211 // Emit inlined call site information. Only emit functions inlined directly
1212 // into the parent function. We'll emit the other sites recursively as part
1213 // of their parent inline site.
1214 for (const DILocation *InlinedAt : FI.ChildSites) {
1215 auto I = FI.InlineSites.find(x: InlinedAt);
1216 assert(I != FI.InlineSites.end() &&
1217 "child site not in function inline site map");
1218 emitInlinedCallSite(FI, InlinedAt, Site: I->second);
1219 }
1220
1221 for (auto Annot : FI.Annotations) {
1222 MCSymbol *Label = Annot.first;
1223 MDTuple *Strs = cast<MDTuple>(Val: Annot.second);
1224 MCSymbol *AnnotEnd = beginSymbolRecord(Kind: SymbolKind::S_ANNOTATION);
1225 OS.emitCOFFSecRel32(Symbol: Label, /*Offset=*/0);
1226 // FIXME: Make sure we don't overflow the max record size.
1227 OS.emitCOFFSectionIndex(Symbol: Label);
1228 OS.emitInt16(Value: Strs->getNumOperands());
1229 for (Metadata *MD : Strs->operands()) {
1230 // MDStrings are null terminated, so we can do EmitBytes and get the
1231 // nice .asciz directive.
1232 StringRef Str = cast<MDString>(Val: MD)->getString();
1233 assert(Str.data()[Str.size()] == '\0' && "non-nullterminated MDString");
1234 OS.emitBytes(Data: StringRef(Str.data(), Str.size() + 1));
1235 }
1236 endSymbolRecord(SymEnd: AnnotEnd);
1237 }
1238
1239 for (auto HeapAllocSite : FI.HeapAllocSites) {
1240 const MCSymbol *BeginLabel = std::get<0>(t&: HeapAllocSite);
1241 const MCSymbol *EndLabel = std::get<1>(t&: HeapAllocSite);
1242 const DIType *DITy = std::get<2>(t&: HeapAllocSite);
1243 MCSymbol *HeapAllocEnd = beginSymbolRecord(Kind: SymbolKind::S_HEAPALLOCSITE);
1244 OS.AddComment(T: "Call site offset");
1245 OS.emitCOFFSecRel32(Symbol: BeginLabel, /*Offset=*/0);
1246 OS.AddComment(T: "Call site section index");
1247 OS.emitCOFFSectionIndex(Symbol: BeginLabel);
1248 OS.AddComment(T: "Call instruction length");
1249 OS.emitAbsoluteSymbolDiff(Hi: EndLabel, Lo: BeginLabel, Size: 2);
1250 OS.AddComment(T: "Type index");
1251 OS.emitInt32(Value: getCompleteTypeIndex(Ty: DITy).getIndex());
1252 endSymbolRecord(SymEnd: HeapAllocEnd);
1253 }
1254
1255 if (SP != nullptr)
1256 emitDebugInfoForUDTs(UDTs: LocalUDTs);
1257
1258 emitDebugInfoForJumpTables(FI);
1259
1260 // We're done with this function.
1261 emitEndSymbolRecord(EndKind: SymbolKind::S_PROC_ID_END);
1262 }
1263 endCVSubsection(EndLabel: SymbolsEnd);
1264
1265 // We have an assembler directive that takes care of the whole line table.
1266 OS.emitCVLinetableDirective(FunctionId: FI.FuncId, FnStart: Fn, FnEnd: FI.End);
1267}
1268
1269CodeViewDebug::LocalVarDef
1270CodeViewDebug::createDefRangeMem(uint16_t CVRegister, int Offset) {
1271 LocalVarDef DR;
1272 DR.InMemory = -1;
1273 DR.DataOffset = Offset;
1274 assert(DR.DataOffset == Offset && "truncation");
1275 DR.IsSubfield = 0;
1276 DR.StructOffset = 0;
1277 DR.CVRegister = CVRegister;
1278 return DR;
1279}
1280
1281void CodeViewDebug::collectVariableInfoFromMFTable(
1282 DenseSet<InlinedEntity> &Processed) {
1283 const MachineFunction &MF = *Asm->MF;
1284 const TargetSubtargetInfo &TSI = MF.getSubtarget();
1285 const TargetFrameLowering *TFI = TSI.getFrameLowering();
1286 const TargetRegisterInfo *TRI = TSI.getRegisterInfo();
1287
1288 for (const MachineFunction::VariableDbgInfo &VI :
1289 MF.getInStackSlotVariableDbgInfo()) {
1290 if (!VI.Var)
1291 continue;
1292 assert(VI.Var->isValidLocationForIntrinsic(VI.Loc) &&
1293 "Expected inlined-at fields to agree");
1294
1295 Processed.insert(V: InlinedEntity(VI.Var, VI.Loc->getInlinedAt()));
1296 LexicalScope *Scope = LScopes.findLexicalScope(DL: VI.Loc);
1297
1298 // If variable scope is not found then skip this variable.
1299 if (!Scope)
1300 continue;
1301
1302 // If the variable has an attached offset expression, extract it.
1303 // FIXME: Try to handle DW_OP_deref as well.
1304 int64_t ExprOffset = 0;
1305 bool Deref = false;
1306 if (VI.Expr) {
1307 // If there is one DW_OP_deref element, use offset of 0 and keep going.
1308 if (VI.Expr->getNumElements() == 1 &&
1309 VI.Expr->getElement(I: 0) == llvm::dwarf::DW_OP_deref)
1310 Deref = true;
1311 else if (!VI.Expr->extractIfOffset(Offset&: ExprOffset))
1312 continue;
1313 }
1314
1315 // Get the frame register used and the offset.
1316 Register FrameReg;
1317 StackOffset FrameOffset =
1318 TFI->getFrameIndexReference(MF: *Asm->MF, FI: VI.getStackSlot(), FrameReg);
1319 uint16_t CVReg = TRI->getCodeViewRegNum(RegNum: FrameReg);
1320
1321 assert(!FrameOffset.getScalable() &&
1322 "Frame offsets with a scalable component are not supported");
1323
1324 // Calculate the label ranges.
1325 LocalVarDef DefRange =
1326 createDefRangeMem(CVRegister: CVReg, Offset: FrameOffset.getFixed() + ExprOffset);
1327
1328 LocalVariable Var;
1329 Var.DIVar = VI.Var;
1330
1331 for (const InsnRange &Range : Scope->getRanges()) {
1332 const MCSymbol *Begin = getLabelBeforeInsn(MI: Range.first);
1333 const MCSymbol *End = getLabelAfterInsn(MI: Range.second);
1334 End = End ? End : Asm->getFunctionEnd();
1335 Var.DefRanges[DefRange].emplace_back(Args&: Begin, Args&: End);
1336 }
1337
1338 if (Deref)
1339 Var.UseReferenceType = true;
1340
1341 recordLocalVariable(Var: std::move(Var), LS: Scope);
1342 }
1343}
1344
1345static bool canUseReferenceType(const DbgVariableLocation &Loc) {
1346 return !Loc.LoadChain.empty() && Loc.LoadChain.back() == 0;
1347}
1348
1349static bool needsReferenceType(const DbgVariableLocation &Loc) {
1350 return Loc.LoadChain.size() == 2 && Loc.LoadChain.back() == 0;
1351}
1352
1353void CodeViewDebug::calculateRanges(
1354 LocalVariable &Var, const DbgValueHistoryMap::Entries &Entries) {
1355 const TargetRegisterInfo *TRI = Asm->MF->getSubtarget().getRegisterInfo();
1356
1357 // Calculate the definition ranges.
1358 for (auto I = Entries.begin(), E = Entries.end(); I != E; ++I) {
1359 const auto &Entry = *I;
1360 if (!Entry.isDbgValue())
1361 continue;
1362 const MachineInstr *DVInst = Entry.getInstr();
1363 assert(DVInst->isDebugValue() && "Invalid History entry");
1364 // FIXME: Find a way to represent constant variables, since they are
1365 // relatively common.
1366 std::optional<DbgVariableLocation> Location =
1367 DbgVariableLocation::extractFromMachineInstruction(Instruction: *DVInst);
1368 if (!Location)
1369 {
1370 // When we don't have a location this is usually because LLVM has
1371 // transformed it into a constant and we only have an llvm.dbg.value. We
1372 // can't represent these well in CodeView since S_LOCAL only works on
1373 // registers and memory locations. Instead, we will pretend this to be a
1374 // constant value to at least have it show up in the debugger.
1375 auto Op = DVInst->getDebugOperand(Index: 0);
1376 if (Op.isImm())
1377 Var.ConstantValue = APSInt(APInt(64, Op.getImm()), false);
1378 continue;
1379 }
1380
1381 // CodeView can only express variables in register and variables in memory
1382 // at a constant offset from a register. However, for variables passed
1383 // indirectly by pointer, it is common for that pointer to be spilled to a
1384 // stack location. For the special case of one offseted load followed by a
1385 // zero offset load (a pointer spilled to the stack), we change the type of
1386 // the local variable from a value type to a reference type. This tricks the
1387 // debugger into doing the load for us.
1388 if (Var.UseReferenceType) {
1389 // We're using a reference type. Drop the last zero offset load.
1390 if (canUseReferenceType(Loc: *Location))
1391 Location->LoadChain.pop_back();
1392 else
1393 continue;
1394 } else if (needsReferenceType(Loc: *Location)) {
1395 // This location can't be expressed without switching to a reference type.
1396 // Start over using that.
1397 Var.UseReferenceType = true;
1398 Var.DefRanges.clear();
1399 calculateRanges(Var, Entries);
1400 return;
1401 }
1402
1403 // We can only handle a register or an offseted load of a register.
1404 if (!Location->Register || Location->LoadChain.size() > 1)
1405 continue;
1406
1407 // Codeview can only express byte-aligned offsets, ensure that we have a
1408 // byte-boundaried location.
1409 if (Location->FragmentInfo)
1410 if (Location->FragmentInfo->OffsetInBits % 8)
1411 continue;
1412
1413 LocalVarDef DR;
1414 DR.CVRegister = TRI->getCodeViewRegNum(RegNum: Location->Register);
1415 DR.InMemory = !Location->LoadChain.empty();
1416 DR.DataOffset =
1417 !Location->LoadChain.empty() ? Location->LoadChain.back() : 0;
1418 if (Location->FragmentInfo) {
1419 DR.IsSubfield = true;
1420 DR.StructOffset = Location->FragmentInfo->OffsetInBits / 8;
1421 } else {
1422 DR.IsSubfield = false;
1423 DR.StructOffset = 0;
1424 }
1425
1426 // Compute the label range.
1427 const MCSymbol *Begin = getLabelBeforeInsn(MI: Entry.getInstr());
1428 const MCSymbol *End;
1429 if (Entry.getEndIndex() != DbgValueHistoryMap::NoEntry) {
1430 auto &EndingEntry = Entries[Entry.getEndIndex()];
1431 End = EndingEntry.isDbgValue()
1432 ? getLabelBeforeInsn(MI: EndingEntry.getInstr())
1433 : getLabelAfterInsn(MI: EndingEntry.getInstr());
1434 } else
1435 End = Asm->getFunctionEnd();
1436
1437 // If the last range end is our begin, just extend the last range.
1438 // Otherwise make a new range.
1439 SmallVectorImpl<std::pair<const MCSymbol *, const MCSymbol *>> &R =
1440 Var.DefRanges[DR];
1441 if (!R.empty() && R.back().second == Begin)
1442 R.back().second = End;
1443 else
1444 R.emplace_back(Args&: Begin, Args&: End);
1445
1446 // FIXME: Do more range combining.
1447 }
1448}
1449
1450void CodeViewDebug::collectVariableInfo(const DISubprogram *SP) {
1451 DenseSet<InlinedEntity> Processed;
1452 // Grab the variable info that was squirreled away in the MMI side-table.
1453 collectVariableInfoFromMFTable(Processed);
1454
1455 for (const auto &I : DbgValues) {
1456 InlinedEntity IV = I.first;
1457 if (Processed.count(V: IV))
1458 continue;
1459 const DILocalVariable *DIVar = cast<DILocalVariable>(Val: IV.first);
1460 const DILocation *InlinedAt = IV.second;
1461
1462 // Instruction ranges, specifying where IV is accessible.
1463 const auto &Entries = I.second;
1464
1465 LexicalScope *Scope = nullptr;
1466 if (InlinedAt)
1467 Scope = LScopes.findInlinedScope(N: DIVar->getScope(), IA: InlinedAt);
1468 else
1469 Scope = LScopes.findLexicalScope(N: DIVar->getScope());
1470 // If variable scope is not found then skip this variable.
1471 if (!Scope)
1472 continue;
1473
1474 LocalVariable Var;
1475 Var.DIVar = DIVar;
1476
1477 calculateRanges(Var, Entries);
1478 recordLocalVariable(Var: std::move(Var), LS: Scope);
1479 }
1480}
1481
1482void CodeViewDebug::beginFunctionImpl(const MachineFunction *MF) {
1483 const TargetSubtargetInfo &TSI = MF->getSubtarget();
1484 const TargetRegisterInfo *TRI = TSI.getRegisterInfo();
1485 const MachineFrameInfo &MFI = MF->getFrameInfo();
1486 const Function &GV = MF->getFunction();
1487 auto Insertion = FnDebugInfo.insert(KV: {&GV, std::make_unique<FunctionInfo>()});
1488 assert(Insertion.second && "function already has info");
1489 CurFn = Insertion.first->second.get();
1490 CurFn->FuncId = NextFuncId++;
1491 CurFn->Begin = Asm->getFunctionBegin();
1492
1493 // The S_FRAMEPROC record reports the stack size, and how many bytes of
1494 // callee-saved registers were used. For targets that don't use a PUSH
1495 // instruction (AArch64), this will be zero.
1496 CurFn->CSRSize = MFI.getCVBytesOfCalleeSavedRegisters();
1497 CurFn->FrameSize = MFI.getStackSize();
1498 CurFn->OffsetAdjustment = MFI.getOffsetAdjustment();
1499 CurFn->HasStackRealignment = TRI->hasStackRealignment(MF: *MF);
1500
1501 // For this function S_FRAMEPROC record, figure out which codeview register
1502 // will be the frame pointer.
1503 CurFn->EncodedParamFramePtrReg = EncodedFramePtrReg::None; // None.
1504 CurFn->EncodedLocalFramePtrReg = EncodedFramePtrReg::None; // None.
1505 if (CurFn->FrameSize > 0) {
1506 if (!TSI.getFrameLowering()->hasFP(MF: *MF)) {
1507 CurFn->EncodedLocalFramePtrReg = EncodedFramePtrReg::StackPtr;
1508 CurFn->EncodedParamFramePtrReg = EncodedFramePtrReg::StackPtr;
1509 } else {
1510 CurFn->HasFramePointer = true;
1511 // If there is an FP, parameters are always relative to it.
1512 CurFn->EncodedParamFramePtrReg = EncodedFramePtrReg::FramePtr;
1513 if (CurFn->HasStackRealignment) {
1514 // If the stack needs realignment, locals are relative to SP or VFRAME.
1515 CurFn->EncodedLocalFramePtrReg = EncodedFramePtrReg::StackPtr;
1516 } else {
1517 // Otherwise, locals are relative to EBP, and we probably have VLAs or
1518 // other stack adjustments.
1519 CurFn->EncodedLocalFramePtrReg = EncodedFramePtrReg::FramePtr;
1520 }
1521 }
1522 }
1523
1524 // Compute other frame procedure options.
1525 FrameProcedureOptions FPO = FrameProcedureOptions::None;
1526 if (MFI.hasVarSizedObjects())
1527 FPO |= FrameProcedureOptions::HasAlloca;
1528 if (MF->exposesReturnsTwice())
1529 FPO |= FrameProcedureOptions::HasSetJmp;
1530 // FIXME: Set HasLongJmp if we ever track that info.
1531 if (MF->hasInlineAsm())
1532 FPO |= FrameProcedureOptions::HasInlineAssembly;
1533 if (GV.hasPersonalityFn()) {
1534 if (isAsynchronousEHPersonality(
1535 Pers: classifyEHPersonality(Pers: GV.getPersonalityFn())))
1536 FPO |= FrameProcedureOptions::HasStructuredExceptionHandling;
1537 else
1538 FPO |= FrameProcedureOptions::HasExceptionHandling;
1539 }
1540 if (GV.hasFnAttribute(Kind: Attribute::InlineHint))
1541 FPO |= FrameProcedureOptions::MarkedInline;
1542 if (GV.hasFnAttribute(Kind: Attribute::Naked))
1543 FPO |= FrameProcedureOptions::Naked;
1544 if (MFI.hasStackProtectorIndex()) {
1545 FPO |= FrameProcedureOptions::SecurityChecks;
1546 if (GV.hasFnAttribute(Kind: Attribute::StackProtectStrong) ||
1547 GV.hasFnAttribute(Kind: Attribute::StackProtectReq)) {
1548 FPO |= FrameProcedureOptions::StrictSecurityChecks;
1549 }
1550 } else if (!GV.hasStackProtectorFnAttr()) {
1551 // __declspec(safebuffers) disables stack guards.
1552 FPO |= FrameProcedureOptions::SafeBuffers;
1553 }
1554 FPO |= FrameProcedureOptions(uint32_t(CurFn->EncodedLocalFramePtrReg) << 14U);
1555 FPO |= FrameProcedureOptions(uint32_t(CurFn->EncodedParamFramePtrReg) << 16U);
1556 if (Asm->TM.getOptLevel() != CodeGenOptLevel::None && !GV.hasOptSize() &&
1557 !GV.hasOptNone())
1558 FPO |= FrameProcedureOptions::OptimizedForSpeed;
1559 if (GV.hasProfileData()) {
1560 FPO |= FrameProcedureOptions::ValidProfileCounts;
1561 FPO |= FrameProcedureOptions::ProfileGuidedOptimization;
1562 }
1563 // FIXME: Set GuardCfg when it is implemented.
1564 CurFn->FrameProcOpts = FPO;
1565
1566 OS.emitCVFuncIdDirective(FunctionId: CurFn->FuncId);
1567
1568 // Find the end of the function prolog. First known non-DBG_VALUE and
1569 // non-frame setup location marks the beginning of the function body.
1570 // FIXME: is there a simpler a way to do this? Can we just search
1571 // for the first instruction of the function, not the last of the prolog?
1572 DebugLoc PrologEndLoc;
1573 bool EmptyPrologue = true;
1574 for (const auto &MBB : *MF) {
1575 for (const auto &MI : MBB) {
1576 if (!MI.isMetaInstruction() && !MI.getFlag(Flag: MachineInstr::FrameSetup) &&
1577 MI.getDebugLoc()) {
1578 PrologEndLoc = MI.getDebugLoc();
1579 break;
1580 } else if (!MI.isMetaInstruction()) {
1581 EmptyPrologue = false;
1582 }
1583 }
1584 }
1585
1586 // Record beginning of function if we have a non-empty prologue.
1587 if (PrologEndLoc && !EmptyPrologue) {
1588 DebugLoc FnStartDL = PrologEndLoc.getFnDebugLoc();
1589 maybeRecordLocation(DL: FnStartDL, MF);
1590 }
1591
1592 // Find heap alloc sites and emit labels around them.
1593 for (const auto &MBB : *MF) {
1594 for (const auto &MI : MBB) {
1595 if (MI.getHeapAllocMarker()) {
1596 requestLabelBeforeInsn(MI: &MI);
1597 requestLabelAfterInsn(MI: &MI);
1598 }
1599 }
1600 }
1601
1602 // Mark branches that may potentially be using jump tables with labels.
1603 bool isThumb = MMI->getModule()->getTargetTriple().getArch() ==
1604 llvm::Triple::ArchType::thumb;
1605 discoverJumpTableBranches(MF, isThumb);
1606}
1607
1608static bool shouldEmitUdt(const DIType *T) {
1609 if (!T)
1610 return false;
1611
1612 // MSVC does not emit UDTs for typedefs that are scoped to classes.
1613 if (T->getTag() == dwarf::DW_TAG_typedef) {
1614 if (DIScope *Scope = T->getScope()) {
1615 switch (Scope->getTag()) {
1616 case dwarf::DW_TAG_structure_type:
1617 case dwarf::DW_TAG_class_type:
1618 case dwarf::DW_TAG_union_type:
1619 return false;
1620 default:
1621 // do nothing.
1622 ;
1623 }
1624 }
1625 }
1626
1627 while (true) {
1628 if (!T || T->isForwardDecl())
1629 return false;
1630
1631 const DIDerivedType *DT = dyn_cast<DIDerivedType>(Val: T);
1632 if (!DT)
1633 return true;
1634 T = DT->getBaseType();
1635 }
1636 return true;
1637}
1638
1639void CodeViewDebug::addToUDTs(const DIType *Ty) {
1640 // Don't record empty UDTs.
1641 if (Ty->getName().empty())
1642 return;
1643 if (!shouldEmitUdt(T: Ty))
1644 return;
1645
1646 SmallVector<StringRef, 5> ParentScopeNames;
1647 const DISubprogram *ClosestSubprogram =
1648 collectParentScopeNames(Scope: Ty->getScope(), QualifiedNameComponents&: ParentScopeNames);
1649
1650 std::string FullyQualifiedName =
1651 formatNestedName(QualifiedNameComponents: ParentScopeNames, TypeName: getPrettyScopeName(Scope: Ty));
1652
1653 if (ClosestSubprogram == nullptr) {
1654 GlobalUDTs.emplace_back(args: std::move(FullyQualifiedName), args&: Ty);
1655 } else if (ClosestSubprogram == CurrentSubprogram) {
1656 LocalUDTs.emplace_back(args: std::move(FullyQualifiedName), args&: Ty);
1657 }
1658
1659 // TODO: What if the ClosestSubprogram is neither null or the current
1660 // subprogram? Currently, the UDT just gets dropped on the floor.
1661 //
1662 // The current behavior is not desirable. To get maximal fidelity, we would
1663 // need to perform all type translation before beginning emission of .debug$S
1664 // and then make LocalUDTs a member of FunctionInfo
1665}
1666
1667TypeIndex CodeViewDebug::lowerType(const DIType *Ty, const DIType *ClassTy) {
1668 // Generic dispatch for lowering an unknown type.
1669 switch (Ty->getTag()) {
1670 case dwarf::DW_TAG_array_type:
1671 return lowerTypeArray(Ty: cast<DICompositeType>(Val: Ty));
1672 case dwarf::DW_TAG_typedef:
1673 return lowerTypeAlias(Ty: cast<DIDerivedType>(Val: Ty));
1674 case dwarf::DW_TAG_base_type:
1675 return lowerTypeBasic(Ty: cast<DIBasicType>(Val: Ty));
1676 case dwarf::DW_TAG_pointer_type:
1677 if (cast<DIDerivedType>(Val: Ty)->getName() == "__vtbl_ptr_type")
1678 return lowerTypeVFTableShape(Ty: cast<DIDerivedType>(Val: Ty));
1679 [[fallthrough]];
1680 case dwarf::DW_TAG_reference_type:
1681 case dwarf::DW_TAG_rvalue_reference_type:
1682 return lowerTypePointer(Ty: cast<DIDerivedType>(Val: Ty));
1683 case dwarf::DW_TAG_ptr_to_member_type:
1684 return lowerTypeMemberPointer(Ty: cast<DIDerivedType>(Val: Ty));
1685 case dwarf::DW_TAG_restrict_type:
1686 case dwarf::DW_TAG_const_type:
1687 case dwarf::DW_TAG_volatile_type:
1688 // TODO: add support for DW_TAG_atomic_type here
1689 return lowerTypeModifier(Ty: cast<DIDerivedType>(Val: Ty));
1690 case dwarf::DW_TAG_subroutine_type:
1691 if (ClassTy) {
1692 // The member function type of a member function pointer has no
1693 // ThisAdjustment.
1694 return lowerTypeMemberFunction(Ty: cast<DISubroutineType>(Val: Ty), ClassTy,
1695 /*ThisAdjustment=*/0,
1696 /*IsStaticMethod=*/false);
1697 }
1698 return lowerTypeFunction(Ty: cast<DISubroutineType>(Val: Ty));
1699 case dwarf::DW_TAG_enumeration_type:
1700 return lowerTypeEnum(Ty: cast<DICompositeType>(Val: Ty));
1701 case dwarf::DW_TAG_class_type:
1702 case dwarf::DW_TAG_structure_type:
1703 return lowerTypeClass(Ty: cast<DICompositeType>(Val: Ty));
1704 case dwarf::DW_TAG_union_type:
1705 return lowerTypeUnion(Ty: cast<DICompositeType>(Val: Ty));
1706 case dwarf::DW_TAG_string_type:
1707 return lowerTypeString(Ty: cast<DIStringType>(Val: Ty));
1708 case dwarf::DW_TAG_unspecified_type:
1709 if (Ty->getName() == "decltype(nullptr)")
1710 return TypeIndex::NullptrT();
1711 return TypeIndex::None();
1712 default:
1713 // Use the null type index.
1714 return TypeIndex();
1715 }
1716}
1717
1718TypeIndex CodeViewDebug::lowerTypeAlias(const DIDerivedType *Ty) {
1719 TypeIndex UnderlyingTypeIndex = getTypeIndex(Ty: Ty->getBaseType());
1720 StringRef TypeName = Ty->getName();
1721
1722 addToUDTs(Ty);
1723
1724 if (UnderlyingTypeIndex == TypeIndex(SimpleTypeKind::Int32Long) &&
1725 TypeName == "HRESULT")
1726 return TypeIndex(SimpleTypeKind::HResult);
1727 if (UnderlyingTypeIndex == TypeIndex(SimpleTypeKind::UInt16Short) &&
1728 TypeName == "wchar_t")
1729 return TypeIndex(SimpleTypeKind::WideCharacter);
1730
1731 return UnderlyingTypeIndex;
1732}
1733
1734TypeIndex CodeViewDebug::lowerTypeArray(const DICompositeType *Ty) {
1735 const DIType *ElementType = Ty->getBaseType();
1736 TypeIndex ElementTypeIndex = getTypeIndex(Ty: ElementType);
1737 // IndexType is size_t, which depends on the bitness of the target.
1738 TypeIndex IndexType = getPointerSizeInBytes() == 8
1739 ? TypeIndex(SimpleTypeKind::UInt64Quad)
1740 : TypeIndex(SimpleTypeKind::UInt32Long);
1741
1742 uint64_t ElementSize = getBaseTypeSize(Ty: ElementType) / 8;
1743
1744 // Add subranges to array type.
1745 DINodeArray Elements = Ty->getElements();
1746 for (int i = Elements.size() - 1; i >= 0; --i) {
1747 const DINode *Element = Elements[i];
1748 assert(Element->getTag() == dwarf::DW_TAG_subrange_type);
1749
1750 const DISubrange *Subrange = cast<DISubrange>(Val: Element);
1751 int64_t Count = -1;
1752
1753 // If Subrange has a Count field, use it.
1754 // Otherwise, if it has an upperboud, use (upperbound - lowerbound + 1),
1755 // where lowerbound is from the LowerBound field of the Subrange,
1756 // or the language default lowerbound if that field is unspecified.
1757 if (auto *CI = dyn_cast_if_present<ConstantInt *>(Val: Subrange->getCount()))
1758 Count = CI->getSExtValue();
1759 else if (auto *UI = dyn_cast_if_present<ConstantInt *>(
1760 Val: Subrange->getUpperBound())) {
1761 // Fortran uses 1 as the default lowerbound; other languages use 0.
1762 int64_t Lowerbound = (moduleIsInFortran()) ? 1 : 0;
1763 auto *LI = dyn_cast_if_present<ConstantInt *>(Val: Subrange->getLowerBound());
1764 Lowerbound = (LI) ? LI->getSExtValue() : Lowerbound;
1765 Count = UI->getSExtValue() - Lowerbound + 1;
1766 }
1767
1768 // Forward declarations of arrays without a size and VLAs use a count of -1.
1769 // Emit a count of zero in these cases to match what MSVC does for arrays
1770 // without a size. MSVC doesn't support VLAs, so it's not clear what we
1771 // should do for them even if we could distinguish them.
1772 if (Count == -1)
1773 Count = 0;
1774
1775 // Update the element size and element type index for subsequent subranges.
1776 ElementSize *= Count;
1777
1778 // If this is the outermost array, use the size from the array. It will be
1779 // more accurate if we had a VLA or an incomplete element type size.
1780 uint64_t ArraySize =
1781 (i == 0 && ElementSize == 0) ? Ty->getSizeInBits() / 8 : ElementSize;
1782
1783 StringRef Name = (i == 0) ? Ty->getName() : "";
1784 ArrayRecord AR(ElementTypeIndex, IndexType, ArraySize, Name);
1785 ElementTypeIndex = TypeTable.writeLeafType(Record&: AR);
1786 }
1787
1788 return ElementTypeIndex;
1789}
1790
1791// This function lowers a Fortran character type (DIStringType).
1792// Note that it handles only the character*n variant (using SizeInBits
1793// field in DIString to describe the type size) at the moment.
1794// Other variants (leveraging the StringLength and StringLengthExp
1795// fields in DIStringType) remain TBD.
1796TypeIndex CodeViewDebug::lowerTypeString(const DIStringType *Ty) {
1797 TypeIndex CharType = TypeIndex(SimpleTypeKind::NarrowCharacter);
1798 uint64_t ArraySize = Ty->getSizeInBits() >> 3;
1799 StringRef Name = Ty->getName();
1800 // IndexType is size_t, which depends on the bitness of the target.
1801 TypeIndex IndexType = getPointerSizeInBytes() == 8
1802 ? TypeIndex(SimpleTypeKind::UInt64Quad)
1803 : TypeIndex(SimpleTypeKind::UInt32Long);
1804
1805 // Create a type of character array of ArraySize.
1806 ArrayRecord AR(CharType, IndexType, ArraySize, Name);
1807
1808 return TypeTable.writeLeafType(Record&: AR);
1809}
1810
1811TypeIndex CodeViewDebug::lowerTypeBasic(const DIBasicType *Ty) {
1812 TypeIndex Index;
1813 dwarf::TypeKind Kind;
1814 uint32_t ByteSize;
1815
1816 Kind = static_cast<dwarf::TypeKind>(Ty->getEncoding());
1817 ByteSize = Ty->getSizeInBits() / 8;
1818
1819 SimpleTypeKind STK = SimpleTypeKind::None;
1820 switch (Kind) {
1821 case dwarf::DW_ATE_address:
1822 // FIXME: Translate
1823 break;
1824 case dwarf::DW_ATE_boolean:
1825 switch (ByteSize) {
1826 case 1: STK = SimpleTypeKind::Boolean8; break;
1827 case 2: STK = SimpleTypeKind::Boolean16; break;
1828 case 4: STK = SimpleTypeKind::Boolean32; break;
1829 case 8: STK = SimpleTypeKind::Boolean64; break;
1830 case 16: STK = SimpleTypeKind::Boolean128; break;
1831 }
1832 break;
1833 case dwarf::DW_ATE_complex_float:
1834 // The CodeView size for a complex represents the size of
1835 // an individual component.
1836 switch (ByteSize) {
1837 case 4: STK = SimpleTypeKind::Complex16; break;
1838 case 8: STK = SimpleTypeKind::Complex32; break;
1839 case 16: STK = SimpleTypeKind::Complex64; break;
1840 case 20: STK = SimpleTypeKind::Complex80; break;
1841 case 32: STK = SimpleTypeKind::Complex128; break;
1842 }
1843 break;
1844 case dwarf::DW_ATE_float:
1845 switch (ByteSize) {
1846 case 2: STK = SimpleTypeKind::Float16; break;
1847 case 4: STK = SimpleTypeKind::Float32; break;
1848 case 6: STK = SimpleTypeKind::Float48; break;
1849 case 8: STK = SimpleTypeKind::Float64; break;
1850 case 10: STK = SimpleTypeKind::Float80; break;
1851 case 16: STK = SimpleTypeKind::Float128; break;
1852 }
1853 break;
1854 case dwarf::DW_ATE_signed:
1855 switch (ByteSize) {
1856 case 1: STK = SimpleTypeKind::SignedCharacter; break;
1857 case 2: STK = SimpleTypeKind::Int16Short; break;
1858 case 4: STK = SimpleTypeKind::Int32; break;
1859 case 8: STK = SimpleTypeKind::Int64Quad; break;
1860 case 16: STK = SimpleTypeKind::Int128Oct; break;
1861 }
1862 break;
1863 case dwarf::DW_ATE_unsigned:
1864 switch (ByteSize) {
1865 case 1: STK = SimpleTypeKind::UnsignedCharacter; break;
1866 case 2: STK = SimpleTypeKind::UInt16Short; break;
1867 case 4: STK = SimpleTypeKind::UInt32; break;
1868 case 8: STK = SimpleTypeKind::UInt64Quad; break;
1869 case 16: STK = SimpleTypeKind::UInt128Oct; break;
1870 }
1871 break;
1872 case dwarf::DW_ATE_UTF:
1873 switch (ByteSize) {
1874 case 1: STK = SimpleTypeKind::Character8; break;
1875 case 2: STK = SimpleTypeKind::Character16; break;
1876 case 4: STK = SimpleTypeKind::Character32; break;
1877 }
1878 break;
1879 case dwarf::DW_ATE_signed_char:
1880 if (ByteSize == 1)
1881 STK = SimpleTypeKind::SignedCharacter;
1882 break;
1883 case dwarf::DW_ATE_unsigned_char:
1884 if (ByteSize == 1)
1885 STK = SimpleTypeKind::UnsignedCharacter;
1886 break;
1887 default:
1888 break;
1889 }
1890
1891 // Apply some fixups based on the source-level type name.
1892 // Include some amount of canonicalization from an old naming scheme Clang
1893 // used to use for integer types (in an outdated effort to be compatible with
1894 // GCC's debug info/GDB's behavior, which has since been addressed).
1895 if (STK == SimpleTypeKind::Int32 &&
1896 (Ty->getName() == "long int" || Ty->getName() == "long"))
1897 STK = SimpleTypeKind::Int32Long;
1898 if (STK == SimpleTypeKind::UInt32 && (Ty->getName() == "long unsigned int" ||
1899 Ty->getName() == "unsigned long"))
1900 STK = SimpleTypeKind::UInt32Long;
1901 if (STK == SimpleTypeKind::UInt16Short &&
1902 (Ty->getName() == "wchar_t" || Ty->getName() == "__wchar_t"))
1903 STK = SimpleTypeKind::WideCharacter;
1904 if ((STK == SimpleTypeKind::SignedCharacter ||
1905 STK == SimpleTypeKind::UnsignedCharacter) &&
1906 Ty->getName() == "char")
1907 STK = SimpleTypeKind::NarrowCharacter;
1908
1909 return TypeIndex(STK);
1910}
1911
1912TypeIndex CodeViewDebug::lowerTypePointer(const DIDerivedType *Ty,
1913 PointerOptions PO) {
1914 TypeIndex PointeeTI = getTypeIndex(Ty: Ty->getBaseType());
1915
1916 // Pointers to simple types without any options can use SimpleTypeMode, rather
1917 // than having a dedicated pointer type record.
1918 if (PointeeTI.isSimple() && PO == PointerOptions::None &&
1919 PointeeTI.getSimpleMode() == SimpleTypeMode::Direct &&
1920 Ty->getTag() == dwarf::DW_TAG_pointer_type) {
1921 SimpleTypeMode Mode = Ty->getSizeInBits() == 64
1922 ? SimpleTypeMode::NearPointer64
1923 : SimpleTypeMode::NearPointer32;
1924 return TypeIndex(PointeeTI.getSimpleKind(), Mode);
1925 }
1926
1927 PointerKind PK =
1928 Ty->getSizeInBits() == 64 ? PointerKind::Near64 : PointerKind::Near32;
1929 PointerMode PM = PointerMode::Pointer;
1930 switch (Ty->getTag()) {
1931 default: llvm_unreachable("not a pointer tag type");
1932 case dwarf::DW_TAG_pointer_type:
1933 PM = PointerMode::Pointer;
1934 break;
1935 case dwarf::DW_TAG_reference_type:
1936 PM = PointerMode::LValueReference;
1937 break;
1938 case dwarf::DW_TAG_rvalue_reference_type:
1939 PM = PointerMode::RValueReference;
1940 break;
1941 }
1942
1943 if (Ty->isObjectPointer())
1944 PO |= PointerOptions::Const;
1945
1946 PointerRecord PR(PointeeTI, PK, PM, PO, Ty->getSizeInBits() / 8);
1947 return TypeTable.writeLeafType(Record&: PR);
1948}
1949
1950static PointerToMemberRepresentation
1951translatePtrToMemberRep(unsigned SizeInBytes, bool IsPMF, unsigned Flags) {
1952 // SizeInBytes being zero generally implies that the member pointer type was
1953 // incomplete, which can happen if it is part of a function prototype. In this
1954 // case, use the unknown model instead of the general model.
1955 if (IsPMF) {
1956 switch (Flags & DINode::FlagPtrToMemberRep) {
1957 case 0:
1958 return SizeInBytes == 0 ? PointerToMemberRepresentation::Unknown
1959 : PointerToMemberRepresentation::GeneralFunction;
1960 case DINode::FlagSingleInheritance:
1961 return PointerToMemberRepresentation::SingleInheritanceFunction;
1962 case DINode::FlagMultipleInheritance:
1963 return PointerToMemberRepresentation::MultipleInheritanceFunction;
1964 case DINode::FlagVirtualInheritance:
1965 return PointerToMemberRepresentation::VirtualInheritanceFunction;
1966 }
1967 } else {
1968 switch (Flags & DINode::FlagPtrToMemberRep) {
1969 case 0:
1970 return SizeInBytes == 0 ? PointerToMemberRepresentation::Unknown
1971 : PointerToMemberRepresentation::GeneralData;
1972 case DINode::FlagSingleInheritance:
1973 return PointerToMemberRepresentation::SingleInheritanceData;
1974 case DINode::FlagMultipleInheritance:
1975 return PointerToMemberRepresentation::MultipleInheritanceData;
1976 case DINode::FlagVirtualInheritance:
1977 return PointerToMemberRepresentation::VirtualInheritanceData;
1978 }
1979 }
1980 llvm_unreachable("invalid ptr to member representation");
1981}
1982
1983TypeIndex CodeViewDebug::lowerTypeMemberPointer(const DIDerivedType *Ty,
1984 PointerOptions PO) {
1985 assert(Ty->getTag() == dwarf::DW_TAG_ptr_to_member_type);
1986 bool IsPMF = isa<DISubroutineType>(Val: Ty->getBaseType());
1987 TypeIndex ClassTI = getTypeIndex(Ty: Ty->getClassType());
1988 TypeIndex PointeeTI =
1989 getTypeIndex(Ty: Ty->getBaseType(), ClassTy: IsPMF ? Ty->getClassType() : nullptr);
1990 PointerKind PK = getPointerSizeInBytes() == 8 ? PointerKind::Near64
1991 : PointerKind::Near32;
1992 PointerMode PM = IsPMF ? PointerMode::PointerToMemberFunction
1993 : PointerMode::PointerToDataMember;
1994
1995 assert(Ty->getSizeInBits() / 8 <= 0xff && "pointer size too big");
1996 uint8_t SizeInBytes = Ty->getSizeInBits() / 8;
1997 MemberPointerInfo MPI(
1998 ClassTI, translatePtrToMemberRep(SizeInBytes, IsPMF, Flags: Ty->getFlags()));
1999 PointerRecord PR(PointeeTI, PK, PM, PO, SizeInBytes, MPI);
2000 return TypeTable.writeLeafType(Record&: PR);
2001}
2002
2003/// Given a DWARF calling convention, get the CodeView equivalent. If we don't
2004/// have a translation, use the NearC convention.
2005static CallingConvention dwarfCCToCodeView(unsigned DwarfCC) {
2006 switch (DwarfCC) {
2007 case dwarf::DW_CC_normal: return CallingConvention::NearC;
2008 case dwarf::DW_CC_BORLAND_msfastcall: return CallingConvention::NearFast;
2009 case dwarf::DW_CC_BORLAND_thiscall: return CallingConvention::ThisCall;
2010 case dwarf::DW_CC_BORLAND_stdcall: return CallingConvention::NearStdCall;
2011 case dwarf::DW_CC_BORLAND_pascal: return CallingConvention::NearPascal;
2012 case dwarf::DW_CC_LLVM_vectorcall: return CallingConvention::NearVector;
2013 }
2014 return CallingConvention::NearC;
2015}
2016
2017TypeIndex CodeViewDebug::lowerTypeModifier(const DIDerivedType *Ty) {
2018 ModifierOptions Mods = ModifierOptions::None;
2019 PointerOptions PO = PointerOptions::None;
2020 bool IsModifier = true;
2021 const DIType *BaseTy = Ty;
2022 while (IsModifier && BaseTy) {
2023 // FIXME: Need to add DWARF tags for __unaligned and _Atomic
2024 switch (BaseTy->getTag()) {
2025 case dwarf::DW_TAG_const_type:
2026 Mods |= ModifierOptions::Const;
2027 PO |= PointerOptions::Const;
2028 break;
2029 case dwarf::DW_TAG_volatile_type:
2030 Mods |= ModifierOptions::Volatile;
2031 PO |= PointerOptions::Volatile;
2032 break;
2033 case dwarf::DW_TAG_restrict_type:
2034 // Only pointer types be marked with __restrict. There is no known flag
2035 // for __restrict in LF_MODIFIER records.
2036 PO |= PointerOptions::Restrict;
2037 break;
2038 default:
2039 IsModifier = false;
2040 break;
2041 }
2042 if (IsModifier)
2043 BaseTy = cast<DIDerivedType>(Val: BaseTy)->getBaseType();
2044 }
2045
2046 // Check if the inner type will use an LF_POINTER record. If so, the
2047 // qualifiers will go in the LF_POINTER record. This comes up for types like
2048 // 'int *const' and 'int *__restrict', not the more common cases like 'const
2049 // char *'.
2050 if (BaseTy) {
2051 switch (BaseTy->getTag()) {
2052 case dwarf::DW_TAG_pointer_type:
2053 case dwarf::DW_TAG_reference_type:
2054 case dwarf::DW_TAG_rvalue_reference_type:
2055 return lowerTypePointer(Ty: cast<DIDerivedType>(Val: BaseTy), PO);
2056 case dwarf::DW_TAG_ptr_to_member_type:
2057 return lowerTypeMemberPointer(Ty: cast<DIDerivedType>(Val: BaseTy), PO);
2058 default:
2059 break;
2060 }
2061 }
2062
2063 TypeIndex ModifiedTI = getTypeIndex(Ty: BaseTy);
2064
2065 // Return the base type index if there aren't any modifiers. For example, the
2066 // metadata could contain restrict wrappers around non-pointer types.
2067 if (Mods == ModifierOptions::None)
2068 return ModifiedTI;
2069
2070 ModifierRecord MR(ModifiedTI, Mods);
2071 return TypeTable.writeLeafType(Record&: MR);
2072}
2073
2074TypeIndex CodeViewDebug::lowerTypeFunction(const DISubroutineType *Ty) {
2075 SmallVector<TypeIndex, 8> ReturnAndArgTypeIndices;
2076 for (const DIType *ArgType : Ty->getTypeArray())
2077 ReturnAndArgTypeIndices.push_back(Elt: getTypeIndex(Ty: ArgType));
2078
2079 // MSVC uses type none for variadic argument.
2080 if (ReturnAndArgTypeIndices.size() > 1 &&
2081 ReturnAndArgTypeIndices.back() == TypeIndex::Void()) {
2082 ReturnAndArgTypeIndices.back() = TypeIndex::None();
2083 }
2084 TypeIndex ReturnTypeIndex = TypeIndex::Void();
2085 ArrayRef<TypeIndex> ArgTypeIndices = {};
2086 if (!ReturnAndArgTypeIndices.empty()) {
2087 auto ReturnAndArgTypesRef = ArrayRef(ReturnAndArgTypeIndices);
2088 ReturnTypeIndex = ReturnAndArgTypesRef.front();
2089 ArgTypeIndices = ReturnAndArgTypesRef.drop_front();
2090 }
2091
2092 ArgListRecord ArgListRec(TypeRecordKind::ArgList, ArgTypeIndices);
2093 TypeIndex ArgListIndex = TypeTable.writeLeafType(Record&: ArgListRec);
2094
2095 CallingConvention CC = dwarfCCToCodeView(DwarfCC: Ty->getCC());
2096
2097 FunctionOptions FO = getFunctionOptions(Ty);
2098 ProcedureRecord Procedure(ReturnTypeIndex, CC, FO, ArgTypeIndices.size(),
2099 ArgListIndex);
2100 return TypeTable.writeLeafType(Record&: Procedure);
2101}
2102
2103TypeIndex CodeViewDebug::lowerTypeMemberFunction(const DISubroutineType *Ty,
2104 const DIType *ClassTy,
2105 int ThisAdjustment,
2106 bool IsStaticMethod,
2107 FunctionOptions FO) {
2108 // Lower the containing class type.
2109 TypeIndex ClassType = getTypeIndex(Ty: ClassTy);
2110
2111 DITypeRefArray ReturnAndArgs = Ty->getTypeArray();
2112
2113 unsigned Index = 0;
2114 SmallVector<TypeIndex, 8> ArgTypeIndices;
2115 TypeIndex ReturnTypeIndex = TypeIndex::Void();
2116 if (ReturnAndArgs.size() > Index) {
2117 ReturnTypeIndex = getTypeIndex(Ty: ReturnAndArgs[Index++]);
2118 }
2119
2120 // If the first argument is a pointer type and this isn't a static method,
2121 // treat it as the special 'this' parameter, which is encoded separately from
2122 // the arguments.
2123 TypeIndex ThisTypeIndex;
2124 if (!IsStaticMethod && ReturnAndArgs.size() > Index) {
2125 if (const DIDerivedType *PtrTy =
2126 dyn_cast_or_null<DIDerivedType>(Val: ReturnAndArgs[Index])) {
2127 if (PtrTy->getTag() == dwarf::DW_TAG_pointer_type) {
2128 ThisTypeIndex = getTypeIndexForThisPtr(PtrTy, SubroutineTy: Ty);
2129 Index++;
2130 }
2131 }
2132 }
2133
2134 while (Index < ReturnAndArgs.size())
2135 ArgTypeIndices.push_back(Elt: getTypeIndex(Ty: ReturnAndArgs[Index++]));
2136
2137 // MSVC uses type none for variadic argument.
2138 if (!ArgTypeIndices.empty() && ArgTypeIndices.back() == TypeIndex::Void())
2139 ArgTypeIndices.back() = TypeIndex::None();
2140
2141 ArgListRecord ArgListRec(TypeRecordKind::ArgList, ArgTypeIndices);
2142 TypeIndex ArgListIndex = TypeTable.writeLeafType(Record&: ArgListRec);
2143
2144 CallingConvention CC = dwarfCCToCodeView(DwarfCC: Ty->getCC());
2145
2146 MemberFunctionRecord MFR(ReturnTypeIndex, ClassType, ThisTypeIndex, CC, FO,
2147 ArgTypeIndices.size(), ArgListIndex, ThisAdjustment);
2148 return TypeTable.writeLeafType(Record&: MFR);
2149}
2150
2151TypeIndex CodeViewDebug::lowerTypeVFTableShape(const DIDerivedType *Ty) {
2152 unsigned VSlotCount =
2153 Ty->getSizeInBits() / (8 * Asm->MAI->getCodePointerSize());
2154 SmallVector<VFTableSlotKind, 4> Slots(VSlotCount, VFTableSlotKind::Near);
2155
2156 VFTableShapeRecord VFTSR(Slots);
2157 return TypeTable.writeLeafType(Record&: VFTSR);
2158}
2159
2160static MemberAccess translateAccessFlags(unsigned RecordTag, unsigned Flags) {
2161 switch (Flags & DINode::FlagAccessibility) {
2162 case DINode::FlagPrivate: return MemberAccess::Private;
2163 case DINode::FlagPublic: return MemberAccess::Public;
2164 case DINode::FlagProtected: return MemberAccess::Protected;
2165 case 0:
2166 // If there was no explicit access control, provide the default for the tag.
2167 return RecordTag == dwarf::DW_TAG_class_type ? MemberAccess::Private
2168 : MemberAccess::Public;
2169 }
2170 llvm_unreachable("access flags are exclusive");
2171}
2172
2173static MethodOptions translateMethodOptionFlags(const DISubprogram *SP) {
2174 if (SP->isArtificial())
2175 return MethodOptions::CompilerGenerated;
2176
2177 // FIXME: Handle other MethodOptions.
2178
2179 return MethodOptions::None;
2180}
2181
2182static MethodKind translateMethodKindFlags(const DISubprogram *SP,
2183 bool Introduced) {
2184 if (SP->getFlags() & DINode::FlagStaticMember)
2185 return MethodKind::Static;
2186
2187 switch (SP->getVirtuality()) {
2188 case dwarf::DW_VIRTUALITY_none:
2189 break;
2190 case dwarf::DW_VIRTUALITY_virtual:
2191 return Introduced ? MethodKind::IntroducingVirtual : MethodKind::Virtual;
2192 case dwarf::DW_VIRTUALITY_pure_virtual:
2193 return Introduced ? MethodKind::PureIntroducingVirtual
2194 : MethodKind::PureVirtual;
2195 default:
2196 llvm_unreachable("unhandled virtuality case");
2197 }
2198
2199 return MethodKind::Vanilla;
2200}
2201
2202static TypeRecordKind getRecordKind(const DICompositeType *Ty) {
2203 switch (Ty->getTag()) {
2204 case dwarf::DW_TAG_class_type:
2205 return TypeRecordKind::Class;
2206 case dwarf::DW_TAG_structure_type:
2207 return TypeRecordKind::Struct;
2208 default:
2209 llvm_unreachable("unexpected tag");
2210 }
2211}
2212
2213/// Return ClassOptions that should be present on both the forward declaration
2214/// and the defintion of a tag type.
2215static ClassOptions getCommonClassOptions(const DICompositeType *Ty) {
2216 ClassOptions CO = ClassOptions::None;
2217
2218 // MSVC always sets this flag, even for local types. Clang doesn't always
2219 // appear to give every type a linkage name, which may be problematic for us.
2220 // FIXME: Investigate the consequences of not following them here.
2221 if (!Ty->getIdentifier().empty())
2222 CO |= ClassOptions::HasUniqueName;
2223
2224 // Put the Nested flag on a type if it appears immediately inside a tag type.
2225 // Do not walk the scope chain. Do not attempt to compute ContainsNestedClass
2226 // here. That flag is only set on definitions, and not forward declarations.
2227 const DIScope *ImmediateScope = Ty->getScope();
2228 if (ImmediateScope && isa<DICompositeType>(Val: ImmediateScope))
2229 CO |= ClassOptions::Nested;
2230
2231 // Put the Scoped flag on function-local types. MSVC puts this flag for enum
2232 // type only when it has an immediate function scope. Clang never puts enums
2233 // inside DILexicalBlock scopes. Enum types, as generated by clang, are
2234 // always in function, class, or file scopes.
2235 if (Ty->getTag() == dwarf::DW_TAG_enumeration_type) {
2236 if (ImmediateScope && isa<DISubprogram>(Val: ImmediateScope))
2237 CO |= ClassOptions::Scoped;
2238 } else {
2239 for (const DIScope *Scope = ImmediateScope; Scope != nullptr;
2240 Scope = Scope->getScope()) {
2241 if (isa<DISubprogram>(Val: Scope)) {
2242 CO |= ClassOptions::Scoped;
2243 break;
2244 }
2245 }
2246 }
2247
2248 return CO;
2249}
2250
2251void CodeViewDebug::addUDTSrcLine(const DIType *Ty, TypeIndex TI) {
2252 switch (Ty->getTag()) {
2253 case dwarf::DW_TAG_class_type:
2254 case dwarf::DW_TAG_structure_type:
2255 case dwarf::DW_TAG_union_type:
2256 case dwarf::DW_TAG_enumeration_type:
2257 break;
2258 default:
2259 return;
2260 }
2261
2262 if (const auto *File = Ty->getFile()) {
2263 StringIdRecord SIDR(TypeIndex(0x0), getFullFilepath(File));
2264 TypeIndex SIDI = TypeTable.writeLeafType(Record&: SIDR);
2265
2266 UdtSourceLineRecord USLR(TI, SIDI, Ty->getLine());
2267 TypeTable.writeLeafType(Record&: USLR);
2268 }
2269}
2270
2271TypeIndex CodeViewDebug::lowerTypeEnum(const DICompositeType *Ty) {
2272 ClassOptions CO = getCommonClassOptions(Ty);
2273 TypeIndex FTI;
2274 unsigned EnumeratorCount = 0;
2275
2276 if (Ty->isForwardDecl()) {
2277 CO |= ClassOptions::ForwardReference;
2278 } else {
2279 ContinuationRecordBuilder ContinuationBuilder;
2280 ContinuationBuilder.begin(RecordKind: ContinuationRecordKind::FieldList);
2281 for (const DINode *Element : Ty->getElements()) {
2282 // We assume that the frontend provides all members in source declaration
2283 // order, which is what MSVC does.
2284 if (auto *Enumerator = dyn_cast_or_null<DIEnumerator>(Val: Element)) {
2285 // FIXME: Is it correct to always emit these as unsigned here?
2286 EnumeratorRecord ER(MemberAccess::Public,
2287 APSInt(Enumerator->getValue(), true),
2288 Enumerator->getName());
2289 ContinuationBuilder.writeMemberType(Record&: ER);
2290 EnumeratorCount++;
2291 }
2292 }
2293 FTI = TypeTable.insertRecord(Builder&: ContinuationBuilder);
2294 }
2295
2296 std::string FullName = getFullyQualifiedName(Ty);
2297
2298 EnumRecord ER(EnumeratorCount, CO, FTI, FullName, Ty->getIdentifier(),
2299 getTypeIndex(Ty: Ty->getBaseType()));
2300 TypeIndex EnumTI = TypeTable.writeLeafType(Record&: ER);
2301
2302 addUDTSrcLine(Ty, TI: EnumTI);
2303
2304 return EnumTI;
2305}
2306
2307//===----------------------------------------------------------------------===//
2308// ClassInfo
2309//===----------------------------------------------------------------------===//
2310
2311struct llvm::ClassInfo {
2312 struct MemberInfo {
2313 const DIDerivedType *MemberTypeNode;
2314 uint64_t BaseOffset;
2315 };
2316 // [MemberInfo]
2317 using MemberList = std::vector<MemberInfo>;
2318
2319 using MethodsList = TinyPtrVector<const DISubprogram *>;
2320 // MethodName -> MethodsList
2321 using MethodsMap = MapVector<MDString *, MethodsList>;
2322
2323 /// Base classes.
2324 std::vector<const DIDerivedType *> Inheritance;
2325
2326 /// Direct members.
2327 MemberList Members;
2328 // Direct overloaded methods gathered by name.
2329 MethodsMap Methods;
2330
2331 TypeIndex VShapeTI;
2332
2333 std::vector<const DIType *> NestedTypes;
2334};
2335
2336void CodeViewDebug::clear() {
2337 assert(CurFn == nullptr);
2338 FileIdMap.clear();
2339 FnDebugInfo.clear();
2340 FileToFilepathMap.clear();
2341 LocalUDTs.clear();
2342 GlobalUDTs.clear();
2343 TypeIndices.clear();
2344 CompleteTypeIndices.clear();
2345 ScopeGlobals.clear();
2346 CVGlobalVariableOffsets.clear();
2347}
2348
2349void CodeViewDebug::collectMemberInfo(ClassInfo &Info,
2350 const DIDerivedType *DDTy) {
2351 if (!DDTy->getName().empty()) {
2352 Info.Members.push_back(x: {.MemberTypeNode: DDTy, .BaseOffset: 0});
2353
2354 // Collect static const data members with values.
2355 if ((DDTy->getFlags() & DINode::FlagStaticMember) ==
2356 DINode::FlagStaticMember) {
2357 if (DDTy->getConstant() && (isa<ConstantInt>(Val: DDTy->getConstant()) ||
2358 isa<ConstantFP>(Val: DDTy->getConstant())))
2359 StaticConstMembers.push_back(Elt: DDTy);
2360 }
2361
2362 return;
2363 }
2364
2365 // An unnamed member may represent a nested struct or union. Attempt to
2366 // interpret the unnamed member as a DICompositeType possibly wrapped in
2367 // qualifier types. Add all the indirect fields to the current record if that
2368 // succeeds, and drop the member if that fails.
2369 assert((DDTy->getOffsetInBits() % 8) == 0 && "Unnamed bitfield member!");
2370 uint64_t Offset = DDTy->getOffsetInBits();
2371 const DIType *Ty = DDTy->getBaseType();
2372 bool FullyResolved = false;
2373 while (!FullyResolved) {
2374 switch (Ty->getTag()) {
2375 case dwarf::DW_TAG_const_type:
2376 case dwarf::DW_TAG_volatile_type:
2377 // FIXME: we should apply the qualifier types to the indirect fields
2378 // rather than dropping them.
2379 Ty = cast<DIDerivedType>(Val: Ty)->getBaseType();
2380 break;
2381 default:
2382 FullyResolved = true;
2383 break;
2384 }
2385 }
2386
2387 const DICompositeType *DCTy = dyn_cast<DICompositeType>(Val: Ty);
2388 if (!DCTy)
2389 return;
2390
2391 ClassInfo NestedInfo = collectClassInfo(Ty: DCTy);
2392 for (const ClassInfo::MemberInfo &IndirectField : NestedInfo.Members)
2393 Info.Members.push_back(
2394 x: {.MemberTypeNode: IndirectField.MemberTypeNode, .BaseOffset: IndirectField.BaseOffset + Offset});
2395}
2396
2397ClassInfo CodeViewDebug::collectClassInfo(const DICompositeType *Ty) {
2398 ClassInfo Info;
2399 // Add elements to structure type.
2400 DINodeArray Elements = Ty->getElements();
2401 for (auto *Element : Elements) {
2402 // We assume that the frontend provides all members in source declaration
2403 // order, which is what MSVC does.
2404 if (!Element)
2405 continue;
2406 if (auto *SP = dyn_cast<DISubprogram>(Val: Element)) {
2407 Info.Methods[SP->getRawName()].push_back(NewVal: SP);
2408 } else if (auto *DDTy = dyn_cast<DIDerivedType>(Val: Element)) {
2409 if (DDTy->getTag() == dwarf::DW_TAG_member) {
2410 collectMemberInfo(Info, DDTy);
2411 } else if (DDTy->getTag() == dwarf::DW_TAG_inheritance) {
2412 Info.Inheritance.push_back(x: DDTy);
2413 } else if (DDTy->getTag() == dwarf::DW_TAG_pointer_type &&
2414 DDTy->getName() == "__vtbl_ptr_type") {
2415 Info.VShapeTI = getTypeIndex(Ty: DDTy);
2416 } else if (DDTy->getTag() == dwarf::DW_TAG_typedef) {
2417 Info.NestedTypes.push_back(x: DDTy);
2418 } else if (DDTy->getTag() == dwarf::DW_TAG_friend) {
2419 // Ignore friend members. It appears that MSVC emitted info about
2420 // friends in the past, but modern versions do not.
2421 }
2422 } else if (auto *Composite = dyn_cast<DICompositeType>(Val: Element)) {
2423 Info.NestedTypes.push_back(x: Composite);
2424 }
2425 // Skip other unrecognized kinds of elements.
2426 }
2427 return Info;
2428}
2429
2430static bool shouldAlwaysEmitCompleteClassType(const DICompositeType *Ty) {
2431 // This routine is used by lowerTypeClass and lowerTypeUnion to determine
2432 // if a complete type should be emitted instead of a forward reference.
2433 return Ty->getName().empty() && Ty->getIdentifier().empty() &&
2434 !Ty->isForwardDecl();
2435}
2436
2437TypeIndex CodeViewDebug::lowerTypeClass(const DICompositeType *Ty) {
2438 // Emit the complete type for unnamed structs. C++ classes with methods
2439 // which have a circular reference back to the class type are expected to
2440 // be named by the front-end and should not be "unnamed". C unnamed
2441 // structs should not have circular references.
2442 if (shouldAlwaysEmitCompleteClassType(Ty)) {
2443 // If this unnamed complete type is already in the process of being defined
2444 // then the description of the type is malformed and cannot be emitted
2445 // into CodeView correctly so report a fatal error.
2446 auto I = CompleteTypeIndices.find(Val: Ty);
2447 if (I != CompleteTypeIndices.end() && I->second == TypeIndex())
2448 report_fatal_error(reason: "cannot debug circular reference to unnamed type");
2449 return getCompleteTypeIndex(Ty);
2450 }
2451
2452 // First, construct the forward decl. Don't look into Ty to compute the
2453 // forward decl options, since it might not be available in all TUs.
2454 TypeRecordKind Kind = getRecordKind(Ty);
2455 ClassOptions CO =
2456 ClassOptions::ForwardReference | getCommonClassOptions(Ty);
2457 std::string FullName = getFullyQualifiedName(Ty);
2458 ClassRecord CR(Kind, 0, CO, TypeIndex(), TypeIndex(), TypeIndex(), 0,
2459 FullName, Ty->getIdentifier());
2460 TypeIndex FwdDeclTI = TypeTable.writeLeafType(Record&: CR);
2461 if (!Ty->isForwardDecl())
2462 DeferredCompleteTypes.push_back(Elt: Ty);
2463 return FwdDeclTI;
2464}
2465
2466TypeIndex CodeViewDebug::lowerCompleteTypeClass(const DICompositeType *Ty) {
2467 // Construct the field list and complete type record.
2468 TypeRecordKind Kind = getRecordKind(Ty);
2469 ClassOptions CO = getCommonClassOptions(Ty);
2470 TypeIndex FieldTI;
2471 TypeIndex VShapeTI;
2472 unsigned FieldCount;
2473 bool ContainsNestedClass;
2474 std::tie(args&: FieldTI, args&: VShapeTI, args&: FieldCount, args&: ContainsNestedClass) =
2475 lowerRecordFieldList(Ty);
2476
2477 if (ContainsNestedClass)
2478 CO |= ClassOptions::ContainsNestedClass;
2479
2480 // MSVC appears to set this flag by searching any destructor or method with
2481 // FunctionOptions::Constructor among the emitted members. Clang AST has all
2482 // the members, however special member functions are not yet emitted into
2483 // debug information. For now checking a class's non-triviality seems enough.
2484 // FIXME: not true for a nested unnamed struct.
2485 if (isNonTrivial(DCTy: Ty))
2486 CO |= ClassOptions::HasConstructorOrDestructor;
2487
2488 std::string FullName = getFullyQualifiedName(Ty);
2489
2490 uint64_t SizeInBytes = Ty->getSizeInBits() / 8;
2491
2492 ClassRecord CR(Kind, FieldCount, CO, FieldTI, TypeIndex(), VShapeTI,
2493 SizeInBytes, FullName, Ty->getIdentifier());
2494 TypeIndex ClassTI = TypeTable.writeLeafType(Record&: CR);
2495
2496 addUDTSrcLine(Ty, TI: ClassTI);
2497
2498 addToUDTs(Ty);
2499
2500 return ClassTI;
2501}
2502
2503TypeIndex CodeViewDebug::lowerTypeUnion(const DICompositeType *Ty) {
2504 // Emit the complete type for unnamed unions.
2505 if (shouldAlwaysEmitCompleteClassType(Ty))
2506 return getCompleteTypeIndex(Ty);
2507
2508 ClassOptions CO =
2509 ClassOptions::ForwardReference | getCommonClassOptions(Ty);
2510 std::string FullName = getFullyQualifiedName(Ty);
2511 UnionRecord UR(0, CO, TypeIndex(), 0, FullName, Ty->getIdentifier());
2512 TypeIndex FwdDeclTI = TypeTable.writeLeafType(Record&: UR);
2513 if (!Ty->isForwardDecl())
2514 DeferredCompleteTypes.push_back(Elt: Ty);
2515 return FwdDeclTI;
2516}
2517
2518TypeIndex CodeViewDebug::lowerCompleteTypeUnion(const DICompositeType *Ty) {
2519 ClassOptions CO = ClassOptions::Sealed | getCommonClassOptions(Ty);
2520 TypeIndex FieldTI;
2521 unsigned FieldCount;
2522 bool ContainsNestedClass;
2523 std::tie(args&: FieldTI, args: std::ignore, args&: FieldCount, args&: ContainsNestedClass) =
2524 lowerRecordFieldList(Ty);
2525
2526 if (ContainsNestedClass)
2527 CO |= ClassOptions::ContainsNestedClass;
2528
2529 uint64_t SizeInBytes = Ty->getSizeInBits() / 8;
2530 std::string FullName = getFullyQualifiedName(Ty);
2531
2532 UnionRecord UR(FieldCount, CO, FieldTI, SizeInBytes, FullName,
2533 Ty->getIdentifier());
2534 TypeIndex UnionTI = TypeTable.writeLeafType(Record&: UR);
2535
2536 addUDTSrcLine(Ty, TI: UnionTI);
2537
2538 addToUDTs(Ty);
2539
2540 return UnionTI;
2541}
2542
2543std::tuple<TypeIndex, TypeIndex, unsigned, bool>
2544CodeViewDebug::lowerRecordFieldList(const DICompositeType *Ty) {
2545 // Manually count members. MSVC appears to count everything that generates a
2546 // field list record. Each individual overload in a method overload group
2547 // contributes to this count, even though the overload group is a single field
2548 // list record.
2549 unsigned MemberCount = 0;
2550 ClassInfo Info = collectClassInfo(Ty);
2551 ContinuationRecordBuilder ContinuationBuilder;
2552 ContinuationBuilder.begin(RecordKind: ContinuationRecordKind::FieldList);
2553
2554 // Create base classes.
2555 for (const DIDerivedType *I : Info.Inheritance) {
2556 if (I->getFlags() & DINode::FlagVirtual) {
2557 // Virtual base.
2558 unsigned VBPtrOffset = I->getVBPtrOffset();
2559 // FIXME: Despite the accessor name, the offset is really in bytes.
2560 unsigned VBTableIndex = I->getOffsetInBits() / 4;
2561 auto RecordKind = (I->getFlags() & DINode::FlagIndirectVirtualBase) == DINode::FlagIndirectVirtualBase
2562 ? TypeRecordKind::IndirectVirtualBaseClass
2563 : TypeRecordKind::VirtualBaseClass;
2564 VirtualBaseClassRecord VBCR(
2565 RecordKind, translateAccessFlags(RecordTag: Ty->getTag(), Flags: I->getFlags()),
2566 getTypeIndex(Ty: I->getBaseType()), getVBPTypeIndex(), VBPtrOffset,
2567 VBTableIndex);
2568
2569 ContinuationBuilder.writeMemberType(Record&: VBCR);
2570 MemberCount++;
2571 } else {
2572 assert(I->getOffsetInBits() % 8 == 0 &&
2573 "bases must be on byte boundaries");
2574 BaseClassRecord BCR(translateAccessFlags(RecordTag: Ty->getTag(), Flags: I->getFlags()),
2575 getTypeIndex(Ty: I->getBaseType()),
2576 I->getOffsetInBits() / 8);
2577 ContinuationBuilder.writeMemberType(Record&: BCR);
2578 MemberCount++;
2579 }
2580 }
2581
2582 // Create members.
2583 for (ClassInfo::MemberInfo &MemberInfo : Info.Members) {
2584 const DIDerivedType *Member = MemberInfo.MemberTypeNode;
2585 TypeIndex MemberBaseType = getTypeIndex(Ty: Member->getBaseType());
2586 StringRef MemberName = Member->getName();
2587 MemberAccess Access =
2588 translateAccessFlags(RecordTag: Ty->getTag(), Flags: Member->getFlags());
2589
2590 if (Member->isStaticMember()) {
2591 StaticDataMemberRecord SDMR(Access, MemberBaseType, MemberName);
2592 ContinuationBuilder.writeMemberType(Record&: SDMR);
2593 MemberCount++;
2594 continue;
2595 }
2596
2597 // Virtual function pointer member.
2598 if ((Member->getFlags() & DINode::FlagArtificial) &&
2599 Member->getName().starts_with(Prefix: "_vptr$")) {
2600 VFPtrRecord VFPR(getTypeIndex(Ty: Member->getBaseType()));
2601 ContinuationBuilder.writeMemberType(Record&: VFPR);
2602 MemberCount++;
2603 continue;
2604 }
2605
2606 // Data member.
2607 uint64_t MemberOffsetInBits =
2608 Member->getOffsetInBits() + MemberInfo.BaseOffset;
2609 if (Member->isBitField()) {
2610 uint64_t StartBitOffset = MemberOffsetInBits;
2611 if (const auto *CI =
2612 dyn_cast_or_null<ConstantInt>(Val: Member->getStorageOffsetInBits())) {
2613 MemberOffsetInBits = CI->getZExtValue() + MemberInfo.BaseOffset;
2614 }
2615 StartBitOffset -= MemberOffsetInBits;
2616 BitFieldRecord BFR(MemberBaseType, Member->getSizeInBits(),
2617 StartBitOffset);
2618 MemberBaseType = TypeTable.writeLeafType(Record&: BFR);
2619 }
2620 uint64_t MemberOffsetInBytes = MemberOffsetInBits / 8;
2621 DataMemberRecord DMR(Access, MemberBaseType, MemberOffsetInBytes,
2622 MemberName);
2623 ContinuationBuilder.writeMemberType(Record&: DMR);
2624 MemberCount++;
2625 }
2626
2627 // Create methods
2628 for (auto &MethodItr : Info.Methods) {
2629 StringRef Name = MethodItr.first->getString();
2630
2631 std::vector<OneMethodRecord> Methods;
2632 for (const DISubprogram *SP : MethodItr.second) {
2633 TypeIndex MethodType = getMemberFunctionType(SP, Class: Ty);
2634 bool Introduced = SP->getFlags() & DINode::FlagIntroducedVirtual;
2635
2636 unsigned VFTableOffset = -1;
2637 if (Introduced)
2638 VFTableOffset = SP->getVirtualIndex() * getPointerSizeInBytes();
2639
2640 Methods.push_back(x: OneMethodRecord(
2641 MethodType, translateAccessFlags(RecordTag: Ty->getTag(), Flags: SP->getFlags()),
2642 translateMethodKindFlags(SP, Introduced),
2643 translateMethodOptionFlags(SP), VFTableOffset, Name));
2644 MemberCount++;
2645 }
2646 assert(!Methods.empty() && "Empty methods map entry");
2647 if (Methods.size() == 1)
2648 ContinuationBuilder.writeMemberType(Record&: Methods[0]);
2649 else {
2650 // FIXME: Make this use its own ContinuationBuilder so that
2651 // MethodOverloadList can be split correctly.
2652 MethodOverloadListRecord MOLR(Methods);
2653 TypeIndex MethodList = TypeTable.writeLeafType(Record&: MOLR);
2654
2655 OverloadedMethodRecord OMR(Methods.size(), MethodList, Name);
2656 ContinuationBuilder.writeMemberType(Record&: OMR);
2657 }
2658 }
2659
2660 // Create nested classes.
2661 for (const DIType *Nested : Info.NestedTypes) {
2662 NestedTypeRecord R(getTypeIndex(Ty: Nested), Nested->getName());
2663 ContinuationBuilder.writeMemberType(Record&: R);
2664 MemberCount++;
2665 }
2666
2667 TypeIndex FieldTI = TypeTable.insertRecord(Builder&: ContinuationBuilder);
2668 return std::make_tuple(args&: FieldTI, args&: Info.VShapeTI, args&: MemberCount,
2669 args: !Info.NestedTypes.empty());
2670}
2671
2672TypeIndex CodeViewDebug::getVBPTypeIndex() {
2673 if (!VBPType.getIndex()) {
2674 // Make a 'const int *' type.
2675 ModifierRecord MR(TypeIndex::Int32(), ModifierOptions::Const);
2676 TypeIndex ModifiedTI = TypeTable.writeLeafType(Record&: MR);
2677
2678 PointerKind PK = getPointerSizeInBytes() == 8 ? PointerKind::Near64
2679 : PointerKind::Near32;
2680 PointerMode PM = PointerMode::Pointer;
2681 PointerOptions PO = PointerOptions::None;
2682 PointerRecord PR(ModifiedTI, PK, PM, PO, getPointerSizeInBytes());
2683 VBPType = TypeTable.writeLeafType(Record&: PR);
2684 }
2685
2686 return VBPType;
2687}
2688
2689TypeIndex CodeViewDebug::getTypeIndex(const DIType *Ty, const DIType *ClassTy) {
2690 // The null DIType is the void type. Don't try to hash it.
2691 if (!Ty)
2692 return TypeIndex::Void();
2693
2694 // Check if we've already translated this type. Don't try to do a
2695 // get-or-create style insertion that caches the hash lookup across the
2696 // lowerType call. It will update the TypeIndices map.
2697 auto I = TypeIndices.find(Val: {Ty, ClassTy});
2698 if (I != TypeIndices.end())
2699 return I->second;
2700
2701 TypeLoweringScope S(*this);
2702 TypeIndex TI = lowerType(Ty, ClassTy);
2703 return recordTypeIndexForDINode(Node: Ty, TI, ClassTy);
2704}
2705
2706codeview::TypeIndex
2707CodeViewDebug::getTypeIndexForThisPtr(const DIDerivedType *PtrTy,
2708 const DISubroutineType *SubroutineTy) {
2709 assert(PtrTy->getTag() == dwarf::DW_TAG_pointer_type &&
2710 "this type must be a pointer type");
2711
2712 PointerOptions Options = PointerOptions::None;
2713 if (SubroutineTy->getFlags() & DINode::DIFlags::FlagLValueReference)
2714 Options = PointerOptions::LValueRefThisPointer;
2715 else if (SubroutineTy->getFlags() & DINode::DIFlags::FlagRValueReference)
2716 Options = PointerOptions::RValueRefThisPointer;
2717
2718 // Check if we've already translated this type. If there is no ref qualifier
2719 // on the function then we look up this pointer type with no associated class
2720 // so that the TypeIndex for the this pointer can be shared with the type
2721 // index for other pointers to this class type. If there is a ref qualifier
2722 // then we lookup the pointer using the subroutine as the parent type.
2723 auto I = TypeIndices.find(Val: {PtrTy, SubroutineTy});
2724 if (I != TypeIndices.end())
2725 return I->second;
2726
2727 TypeLoweringScope S(*this);
2728 TypeIndex TI = lowerTypePointer(Ty: PtrTy, PO: Options);
2729 return recordTypeIndexForDINode(Node: PtrTy, TI, ClassTy: SubroutineTy);
2730}
2731
2732TypeIndex CodeViewDebug::getTypeIndexForReferenceTo(const DIType *Ty) {
2733 PointerRecord PR(getTypeIndex(Ty),
2734 getPointerSizeInBytes() == 8 ? PointerKind::Near64
2735 : PointerKind::Near32,
2736 PointerMode::LValueReference, PointerOptions::None,
2737 Ty->getSizeInBits() / 8);
2738 return TypeTable.writeLeafType(Record&: PR);
2739}
2740
2741TypeIndex CodeViewDebug::getCompleteTypeIndex(const DIType *Ty) {
2742 // The null DIType is the void type. Don't try to hash it.
2743 if (!Ty)
2744 return TypeIndex::Void();
2745
2746 // Look through typedefs when getting the complete type index. Call
2747 // getTypeIndex on the typdef to ensure that any UDTs are accumulated and are
2748 // emitted only once.
2749 if (Ty->getTag() == dwarf::DW_TAG_typedef)
2750 (void)getTypeIndex(Ty);
2751 while (Ty->getTag() == dwarf::DW_TAG_typedef)
2752 Ty = cast<DIDerivedType>(Val: Ty)->getBaseType();
2753
2754 // If this is a non-record type, the complete type index is the same as the
2755 // normal type index. Just call getTypeIndex.
2756 switch (Ty->getTag()) {
2757 case dwarf::DW_TAG_class_type:
2758 case dwarf::DW_TAG_structure_type:
2759 case dwarf::DW_TAG_union_type:
2760 break;
2761 default:
2762 return getTypeIndex(Ty);
2763 }
2764
2765 const auto *CTy = cast<DICompositeType>(Val: Ty);
2766
2767 TypeLoweringScope S(*this);
2768
2769 // Make sure the forward declaration is emitted first. It's unclear if this
2770 // is necessary, but MSVC does it, and we should follow suit until we can show
2771 // otherwise.
2772 // We only emit a forward declaration for named types.
2773 if (!CTy->getName().empty() || !CTy->getIdentifier().empty()) {
2774 TypeIndex FwdDeclTI = getTypeIndex(Ty: CTy);
2775
2776 // Just use the forward decl if we don't have complete type info. This
2777 // might happen if the frontend is using modules and expects the complete
2778 // definition to be emitted elsewhere.
2779 if (CTy->isForwardDecl())
2780 return FwdDeclTI;
2781 }
2782
2783 // Check if we've already translated the complete record type.
2784 // Insert the type with a null TypeIndex to signify that the type is currently
2785 // being lowered.
2786 auto InsertResult = CompleteTypeIndices.try_emplace(Key: CTy);
2787 if (!InsertResult.second)
2788 return InsertResult.first->second;
2789
2790 TypeIndex TI;
2791 switch (CTy->getTag()) {
2792 case dwarf::DW_TAG_class_type:
2793 case dwarf::DW_TAG_structure_type:
2794 TI = lowerCompleteTypeClass(Ty: CTy);
2795 break;
2796 case dwarf::DW_TAG_union_type:
2797 TI = lowerCompleteTypeUnion(Ty: CTy);
2798 break;
2799 default:
2800 llvm_unreachable("not a record");
2801 }
2802
2803 // Update the type index associated with this CompositeType. This cannot
2804 // use the 'InsertResult' iterator above because it is potentially
2805 // invalidated by map insertions which can occur while lowering the class
2806 // type above.
2807 CompleteTypeIndices[CTy] = TI;
2808 return TI;
2809}
2810
2811/// Emit all the deferred complete record types. Try to do this in FIFO order,
2812/// and do this until fixpoint, as each complete record type typically
2813/// references
2814/// many other record types.
2815void CodeViewDebug::emitDeferredCompleteTypes() {
2816 SmallVector<const DICompositeType *, 4> TypesToEmit;
2817 while (!DeferredCompleteTypes.empty()) {
2818 std::swap(LHS&: DeferredCompleteTypes, RHS&: TypesToEmit);
2819 for (const DICompositeType *RecordTy : TypesToEmit)
2820 getCompleteTypeIndex(Ty: RecordTy);
2821 TypesToEmit.clear();
2822 }
2823}
2824
2825void CodeViewDebug::emitLocalVariableList(const FunctionInfo &FI,
2826 ArrayRef<LocalVariable> Locals) {
2827 // Get the sorted list of parameters and emit them first.
2828 SmallVector<const LocalVariable *, 6> Params;
2829 for (const LocalVariable &L : Locals)
2830 if (L.DIVar->isParameter())
2831 Params.push_back(Elt: &L);
2832 llvm::sort(C&: Params, Comp: [](const LocalVariable *L, const LocalVariable *R) {
2833 return L->DIVar->getArg() < R->DIVar->getArg();
2834 });
2835 for (const LocalVariable *L : Params)
2836 emitLocalVariable(FI, Var: *L);
2837
2838 // Next emit all non-parameters in the order that we found them.
2839 for (const LocalVariable &L : Locals) {
2840 if (!L.DIVar->isParameter()) {
2841 if (L.ConstantValue) {
2842 // If ConstantValue is set we will emit it as a S_CONSTANT instead of a
2843 // S_LOCAL in order to be able to represent it at all.
2844 const DIType *Ty = L.DIVar->getType();
2845 APSInt Val(*L.ConstantValue);
2846 emitConstantSymbolRecord(DTy: Ty, Value&: Val, QualifiedName: std::string(L.DIVar->getName()));
2847 } else {
2848 emitLocalVariable(FI, Var: L);
2849 }
2850 }
2851 }
2852}
2853
2854void CodeViewDebug::emitLocalVariable(const FunctionInfo &FI,
2855 const LocalVariable &Var) {
2856 // LocalSym record, see SymbolRecord.h for more info.
2857 MCSymbol *LocalEnd = beginSymbolRecord(Kind: SymbolKind::S_LOCAL);
2858
2859 LocalSymFlags Flags = LocalSymFlags::None;
2860 if (Var.DIVar->isParameter())
2861 Flags |= LocalSymFlags::IsParameter;
2862 if (Var.DefRanges.empty())
2863 Flags |= LocalSymFlags::IsOptimizedOut;
2864
2865 OS.AddComment(T: "TypeIndex");
2866 TypeIndex TI = Var.UseReferenceType
2867 ? getTypeIndexForReferenceTo(Ty: Var.DIVar->getType())
2868 : getCompleteTypeIndex(Ty: Var.DIVar->getType());
2869 OS.emitInt32(Value: TI.getIndex());
2870 OS.AddComment(T: "Flags");
2871 OS.emitInt16(Value: static_cast<uint16_t>(Flags));
2872 // Truncate the name so we won't overflow the record length field.
2873 emitNullTerminatedSymbolName(OS, S: Var.DIVar->getName());
2874 endSymbolRecord(SymEnd: LocalEnd);
2875
2876 // Calculate the on disk prefix of the appropriate def range record. The
2877 // records and on disk formats are described in SymbolRecords.h. BytePrefix
2878 // should be big enough to hold all forms without memory allocation.
2879 SmallString<20> BytePrefix;
2880 for (const auto &Pair : Var.DefRanges) {
2881 LocalVarDef DefRange = Pair.first;
2882 const auto &Ranges = Pair.second;
2883 BytePrefix.clear();
2884 if (DefRange.InMemory) {
2885 int Offset = DefRange.DataOffset;
2886 unsigned Reg = DefRange.CVRegister;
2887
2888 // 32-bit x86 call sequences often use PUSH instructions, which disrupt
2889 // ESP-relative offsets. Use the virtual frame pointer, VFRAME or $T0,
2890 // instead. In frames without stack realignment, $T0 will be the CFA.
2891 if (RegisterId(Reg) == RegisterId::ESP) {
2892 Reg = unsigned(RegisterId::VFRAME);
2893 Offset += FI.OffsetAdjustment;
2894 }
2895
2896 // If we can use the chosen frame pointer for the frame and this isn't a
2897 // sliced aggregate, use the smaller S_DEFRANGE_FRAMEPOINTER_REL record.
2898 // Otherwise, use S_DEFRANGE_REGISTER_REL.
2899 EncodedFramePtrReg EncFP = encodeFramePtrReg(Reg: RegisterId(Reg), CPU: TheCPU);
2900 if (!DefRange.IsSubfield && EncFP != EncodedFramePtrReg::None &&
2901 (bool(Flags & LocalSymFlags::IsParameter)
2902 ? (EncFP == FI.EncodedParamFramePtrReg)
2903 : (EncFP == FI.EncodedLocalFramePtrReg))) {
2904 DefRangeFramePointerRelHeader DRHdr;
2905 DRHdr.Offset = Offset;
2906 OS.emitCVDefRangeDirective(Ranges, DRHdr);
2907 } else {
2908 uint16_t RegRelFlags = 0;
2909 if (DefRange.IsSubfield) {
2910 RegRelFlags = DefRangeRegisterRelSym::IsSubfieldFlag |
2911 (DefRange.StructOffset
2912 << DefRangeRegisterRelSym::OffsetInParentShift);
2913 }
2914 DefRangeRegisterRelHeader DRHdr;
2915 DRHdr.Register = Reg;
2916 DRHdr.Flags = RegRelFlags;
2917 DRHdr.BasePointerOffset = Offset;
2918 OS.emitCVDefRangeDirective(Ranges, DRHdr);
2919 }
2920 } else {
2921 assert(DefRange.DataOffset == 0 && "unexpected offset into register");
2922 if (DefRange.IsSubfield) {
2923 DefRangeSubfieldRegisterHeader DRHdr;
2924 DRHdr.Register = DefRange.CVRegister;
2925 DRHdr.MayHaveNoName = 0;
2926 DRHdr.OffsetInParent = DefRange.StructOffset;
2927 OS.emitCVDefRangeDirective(Ranges, DRHdr);
2928 } else {
2929 DefRangeRegisterHeader DRHdr;
2930 DRHdr.Register = DefRange.CVRegister;
2931 DRHdr.MayHaveNoName = 0;
2932 OS.emitCVDefRangeDirective(Ranges, DRHdr);
2933 }
2934 }
2935 }
2936}
2937
2938void CodeViewDebug::emitLexicalBlockList(ArrayRef<LexicalBlock *> Blocks,
2939 const FunctionInfo& FI) {
2940 for (LexicalBlock *Block : Blocks)
2941 emitLexicalBlock(Block: *Block, FI);
2942}
2943
2944/// Emit an S_BLOCK32 and S_END record pair delimiting the contents of a
2945/// lexical block scope.
2946void CodeViewDebug::emitLexicalBlock(const LexicalBlock &Block,
2947 const FunctionInfo& FI) {
2948 MCSymbol *RecordEnd = beginSymbolRecord(Kind: SymbolKind::S_BLOCK32);
2949 OS.AddComment(T: "PtrParent");
2950 OS.emitInt32(Value: 0); // PtrParent
2951 OS.AddComment(T: "PtrEnd");
2952 OS.emitInt32(Value: 0); // PtrEnd
2953 OS.AddComment(T: "Code size");
2954 OS.emitAbsoluteSymbolDiff(Hi: Block.End, Lo: Block.Begin, Size: 4); // Code Size
2955 OS.AddComment(T: "Function section relative address");
2956 OS.emitCOFFSecRel32(Symbol: Block.Begin, /*Offset=*/0); // Func Offset
2957 OS.AddComment(T: "Function section index");
2958 OS.emitCOFFSectionIndex(Symbol: FI.Begin); // Func Symbol
2959 OS.AddComment(T: "Lexical block name");
2960 emitNullTerminatedSymbolName(OS, S: Block.Name); // Name
2961 endSymbolRecord(SymEnd: RecordEnd);
2962
2963 // Emit variables local to this lexical block.
2964 emitLocalVariableList(FI, Locals: Block.Locals);
2965 emitGlobalVariableList(Globals: Block.Globals);
2966
2967 // Emit lexical blocks contained within this block.
2968 emitLexicalBlockList(Blocks: Block.Children, FI);
2969
2970 // Close the lexical block scope.
2971 emitEndSymbolRecord(EndKind: SymbolKind::S_END);
2972}
2973
2974/// Convenience routine for collecting lexical block information for a list
2975/// of lexical scopes.
2976void CodeViewDebug::collectLexicalBlockInfo(
2977 SmallVectorImpl<LexicalScope *> &Scopes,
2978 SmallVectorImpl<LexicalBlock *> &Blocks,
2979 SmallVectorImpl<LocalVariable> &Locals,
2980 SmallVectorImpl<CVGlobalVariable> &Globals) {
2981 for (LexicalScope *Scope : Scopes)
2982 collectLexicalBlockInfo(Scope&: *Scope, ParentBlocks&: Blocks, ParentLocals&: Locals, ParentGlobals&: Globals);
2983}
2984
2985/// Populate the lexical blocks and local variable lists of the parent with
2986/// information about the specified lexical scope.
2987void CodeViewDebug::collectLexicalBlockInfo(
2988 LexicalScope &Scope,
2989 SmallVectorImpl<LexicalBlock *> &ParentBlocks,
2990 SmallVectorImpl<LocalVariable> &ParentLocals,
2991 SmallVectorImpl<CVGlobalVariable> &ParentGlobals) {
2992 if (Scope.isAbstractScope())
2993 return;
2994
2995 // Gather information about the lexical scope including local variables,
2996 // global variables, and address ranges.
2997 bool IgnoreScope = false;
2998 auto LI = ScopeVariables.find(Val: &Scope);
2999 SmallVectorImpl<LocalVariable> *Locals =
3000 LI != ScopeVariables.end() ? &LI->second : nullptr;
3001 auto GI = ScopeGlobals.find(Val: Scope.getScopeNode());
3002 SmallVectorImpl<CVGlobalVariable> *Globals =
3003 GI != ScopeGlobals.end() ? GI->second.get() : nullptr;
3004 const DILexicalBlock *DILB = dyn_cast<DILexicalBlock>(Val: Scope.getScopeNode());
3005 const SmallVectorImpl<InsnRange> &Ranges = Scope.getRanges();
3006
3007 // Ignore lexical scopes which do not contain variables.
3008 if (!Locals && !Globals)
3009 IgnoreScope = true;
3010
3011 // Ignore lexical scopes which are not lexical blocks.
3012 if (!DILB)
3013 IgnoreScope = true;
3014
3015 // Ignore scopes which have too many address ranges to represent in the
3016 // current CodeView format or do not have a valid address range.
3017 //
3018 // For lexical scopes with multiple address ranges you may be tempted to
3019 // construct a single range covering every instruction where the block is
3020 // live and everything in between. Unfortunately, Visual Studio only
3021 // displays variables from the first matching lexical block scope. If the
3022 // first lexical block contains exception handling code or cold code which
3023 // is moved to the bottom of the routine creating a single range covering
3024 // nearly the entire routine, then it will hide all other lexical blocks
3025 // and the variables they contain.
3026 if (Ranges.size() != 1 || !getLabelAfterInsn(MI: Ranges.front().second))
3027 IgnoreScope = true;
3028
3029 if (IgnoreScope) {
3030 // This scope can be safely ignored and eliminating it will reduce the
3031 // size of the debug information. Be sure to collect any variable and scope
3032 // information from the this scope or any of its children and collapse them
3033 // into the parent scope.
3034 if (Locals)
3035 ParentLocals.append(in_start: Locals->begin(), in_end: Locals->end());
3036 if (Globals)
3037 ParentGlobals.append(in_start: Globals->begin(), in_end: Globals->end());
3038 collectLexicalBlockInfo(Scopes&: Scope.getChildren(),
3039 Blocks&: ParentBlocks,
3040 Locals&: ParentLocals,
3041 Globals&: ParentGlobals);
3042 return;
3043 }
3044
3045 // Create a new CodeView lexical block for this lexical scope. If we've
3046 // seen this DILexicalBlock before then the scope tree is malformed and
3047 // we can handle this gracefully by not processing it a second time.
3048 auto BlockInsertion = CurFn->LexicalBlocks.try_emplace(k: DILB);
3049 if (!BlockInsertion.second)
3050 return;
3051
3052 // Create a lexical block containing the variables and collect the
3053 // lexical block information for the children.
3054 const InsnRange &Range = Ranges.front();
3055 assert(Range.first && Range.second);
3056 LexicalBlock &Block = BlockInsertion.first->second;
3057 Block.Begin = getLabelBeforeInsn(MI: Range.first);
3058 Block.End = getLabelAfterInsn(MI: Range.second);
3059 assert(Block.Begin && "missing label for scope begin");
3060 assert(Block.End && "missing label for scope end");
3061 Block.Name = DILB->getName();
3062 if (Locals)
3063 Block.Locals = std::move(*Locals);
3064 if (Globals)
3065 Block.Globals = std::move(*Globals);
3066 ParentBlocks.push_back(Elt: &Block);
3067 collectLexicalBlockInfo(Scopes&: Scope.getChildren(),
3068 Blocks&: Block.Children,
3069 Locals&: Block.Locals,
3070 Globals&: Block.Globals);
3071}
3072
3073void CodeViewDebug::endFunctionImpl(const MachineFunction *MF) {
3074 const Function &GV = MF->getFunction();
3075 assert(FnDebugInfo.count(&GV));
3076 assert(CurFn == FnDebugInfo[&GV].get());
3077
3078 collectVariableInfo(SP: GV.getSubprogram());
3079
3080 // Build the lexical block structure to emit for this routine.
3081 if (LexicalScope *CFS = LScopes.getCurrentFunctionScope())
3082 collectLexicalBlockInfo(Scope&: *CFS,
3083 ParentBlocks&: CurFn->ChildBlocks,
3084 ParentLocals&: CurFn->Locals,
3085 ParentGlobals&: CurFn->Globals);
3086
3087 // Clear the scope and variable information from the map which will not be
3088 // valid after we have finished processing this routine. This also prepares
3089 // the map for the subsequent routine.
3090 ScopeVariables.clear();
3091
3092 // Don't emit anything if we don't have any line tables.
3093 // Thunks are compiler-generated and probably won't have source correlation.
3094 if (!CurFn->HaveLineInfo && !GV.getSubprogram()->isThunk()) {
3095 FnDebugInfo.erase(Key: &GV);
3096 CurFn = nullptr;
3097 return;
3098 }
3099
3100 // Find heap alloc sites and add to list.
3101 for (const auto &MBB : *MF) {
3102 for (const auto &MI : MBB) {
3103 if (MDNode *MD = MI.getHeapAllocMarker()) {
3104 CurFn->HeapAllocSites.push_back(x: std::make_tuple(args: getLabelBeforeInsn(MI: &MI),
3105 args: getLabelAfterInsn(MI: &MI),
3106 args: dyn_cast<DIType>(Val: MD)));
3107 }
3108 }
3109 }
3110
3111 bool isThumb = MMI->getModule()->getTargetTriple().getArch() ==
3112 llvm::Triple::ArchType::thumb;
3113 collectDebugInfoForJumpTables(MF, isThumb);
3114
3115 CurFn->Annotations = MF->getCodeViewAnnotations();
3116
3117 CurFn->End = Asm->getFunctionEnd();
3118
3119 CurFn = nullptr;
3120}
3121
3122// Usable locations are valid with non-zero line numbers. A line number of zero
3123// corresponds to optimized code that doesn't have a distinct source location.
3124// In this case, we try to use the previous or next source location depending on
3125// the context.
3126static bool isUsableDebugLoc(DebugLoc DL) {
3127 return DL && DL.getLine() != 0;
3128}
3129
3130void CodeViewDebug::beginInstruction(const MachineInstr *MI) {
3131 DebugHandlerBase::beginInstruction(MI);
3132
3133 // Ignore DBG_VALUE and DBG_LABEL locations and function prologue.
3134 if (!Asm || !CurFn || MI->isDebugInstr() ||
3135 MI->getFlag(Flag: MachineInstr::FrameSetup))
3136 return;
3137
3138 // If the first instruction of a new MBB has no location, find the first
3139 // instruction with a location and use that.
3140 DebugLoc DL = MI->getDebugLoc();
3141 if (!isUsableDebugLoc(DL) && MI->getParent() != PrevInstBB) {
3142 for (const auto &NextMI : *MI->getParent()) {
3143 if (NextMI.isDebugInstr())
3144 continue;
3145 DL = NextMI.getDebugLoc();
3146 if (isUsableDebugLoc(DL))
3147 break;
3148 }
3149 // FIXME: Handle the case where the BB has no valid locations. This would
3150 // probably require doing a real dataflow analysis.
3151 }
3152 PrevInstBB = MI->getParent();
3153
3154 // If we still don't have a debug location, don't record a location.
3155 if (!isUsableDebugLoc(DL))
3156 return;
3157
3158 maybeRecordLocation(DL, MF: Asm->MF);
3159}
3160
3161MCSymbol *CodeViewDebug::beginCVSubsection(DebugSubsectionKind Kind) {
3162 MCSymbol *BeginLabel = MMI->getContext().createTempSymbol(),
3163 *EndLabel = MMI->getContext().createTempSymbol();
3164 OS.emitInt32(Value: unsigned(Kind));
3165 OS.AddComment(T: "Subsection size");
3166 OS.emitAbsoluteSymbolDiff(Hi: EndLabel, Lo: BeginLabel, Size: 4);
3167 OS.emitLabel(Symbol: BeginLabel);
3168 return EndLabel;
3169}
3170
3171void CodeViewDebug::endCVSubsection(MCSymbol *EndLabel) {
3172 OS.emitLabel(Symbol: EndLabel);
3173 // Every subsection must be aligned to a 4-byte boundary.
3174 OS.emitValueToAlignment(Alignment: Align(4));
3175}
3176
3177static StringRef getSymbolName(SymbolKind SymKind) {
3178 for (const EnumEntry<SymbolKind> &EE : getSymbolTypeNames())
3179 if (EE.Value == SymKind)
3180 return EE.Name;
3181 return "";
3182}
3183
3184MCSymbol *CodeViewDebug::beginSymbolRecord(SymbolKind SymKind) {
3185 MCSymbol *BeginLabel = MMI->getContext().createTempSymbol(),
3186 *EndLabel = MMI->getContext().createTempSymbol();
3187 OS.AddComment(T: "Record length");
3188 OS.emitAbsoluteSymbolDiff(Hi: EndLabel, Lo: BeginLabel, Size: 2);
3189 OS.emitLabel(Symbol: BeginLabel);
3190 if (OS.isVerboseAsm())
3191 OS.AddComment(T: "Record kind: " + getSymbolName(SymKind));
3192 OS.emitInt16(Value: unsigned(SymKind));
3193 return EndLabel;
3194}
3195
3196void CodeViewDebug::endSymbolRecord(MCSymbol *SymEnd) {
3197 // MSVC does not pad out symbol records to four bytes, but LLVM does to avoid
3198 // an extra copy of every symbol record in LLD. This increases object file
3199 // size by less than 1% in the clang build, and is compatible with the Visual
3200 // C++ linker.
3201 OS.emitValueToAlignment(Alignment: Align(4));
3202 OS.emitLabel(Symbol: SymEnd);
3203}
3204
3205void CodeViewDebug::emitEndSymbolRecord(SymbolKind EndKind) {
3206 OS.AddComment(T: "Record length");
3207 OS.emitInt16(Value: 2);
3208 if (OS.isVerboseAsm())
3209 OS.AddComment(T: "Record kind: " + getSymbolName(SymKind: EndKind));
3210 OS.emitInt16(Value: uint16_t(EndKind)); // Record Kind
3211}
3212
3213void CodeViewDebug::emitDebugInfoForUDTs(
3214 const std::vector<std::pair<std::string, const DIType *>> &UDTs) {
3215#ifndef NDEBUG
3216 size_t OriginalSize = UDTs.size();
3217#endif
3218 for (const auto &UDT : UDTs) {
3219 const DIType *T = UDT.second;
3220 assert(shouldEmitUdt(T));
3221 MCSymbol *UDTRecordEnd = beginSymbolRecord(SymKind: SymbolKind::S_UDT);
3222 OS.AddComment(T: "Type");
3223 OS.emitInt32(Value: getCompleteTypeIndex(Ty: T).getIndex());
3224 assert(OriginalSize == UDTs.size() &&
3225 "getCompleteTypeIndex found new UDTs!");
3226 emitNullTerminatedSymbolName(OS, S: UDT.first);
3227 endSymbolRecord(SymEnd: UDTRecordEnd);
3228 }
3229}
3230
3231void CodeViewDebug::collectGlobalVariableInfo() {
3232 DenseMap<const DIGlobalVariableExpression *, const GlobalVariable *>
3233 GlobalMap;
3234 for (const GlobalVariable &GV : MMI->getModule()->globals()) {
3235 SmallVector<DIGlobalVariableExpression *, 1> GVEs;
3236 GV.getDebugInfo(GVs&: GVEs);
3237 for (const auto *GVE : GVEs)
3238 GlobalMap[GVE] = &GV;
3239 }
3240
3241 NamedMDNode *CUs = MMI->getModule()->getNamedMetadata(Name: "llvm.dbg.cu");
3242 for (const MDNode *Node : CUs->operands()) {
3243 const auto *CU = cast<DICompileUnit>(Val: Node);
3244 for (const auto *GVE : CU->getGlobalVariables()) {
3245 const DIGlobalVariable *DIGV = GVE->getVariable();
3246 const DIExpression *DIE = GVE->getExpression();
3247 // Don't emit string literals in CodeView, as the only useful parts are
3248 // generally the filename and line number, which isn't possible to output
3249 // in CodeView. String literals should be the only unnamed GlobalVariable
3250 // with debug info.
3251 if (DIGV->getName().empty()) continue;
3252
3253 if ((DIE->getNumElements() == 2) &&
3254 (DIE->getElement(I: 0) == dwarf::DW_OP_plus_uconst))
3255 // Record the constant offset for the variable.
3256 //
3257 // A Fortran common block uses this idiom to encode the offset
3258 // of a variable from the common block's starting address.
3259 CVGlobalVariableOffsets.insert(
3260 KV: std::make_pair(x&: DIGV, y: DIE->getElement(I: 1)));
3261
3262 // Emit constant global variables in a global symbol section.
3263 if (GlobalMap.count(Val: GVE) == 0 && DIE->isConstant()) {
3264 CVGlobalVariable CVGV = {.DIGV: DIGV, .GVInfo: DIE};
3265 GlobalVariables.emplace_back(Args: std::move(CVGV));
3266 }
3267
3268 const auto *GV = GlobalMap.lookup(Val: GVE);
3269 if (!GV || GV->isDeclarationForLinker())
3270 continue;
3271
3272 DIScope *Scope = DIGV->getScope();
3273 SmallVector<CVGlobalVariable, 1> *VariableList;
3274 if (Scope && isa<DILocalScope>(Val: Scope)) {
3275 // Locate a global variable list for this scope, creating one if
3276 // necessary.
3277 auto Insertion = ScopeGlobals.insert(
3278 KV: {Scope, std::unique_ptr<GlobalVariableList>()});
3279 if (Insertion.second)
3280 Insertion.first->second = std::make_unique<GlobalVariableList>();
3281 VariableList = Insertion.first->second.get();
3282 } else if (GV->hasComdat())
3283 // Emit this global variable into a COMDAT section.
3284 VariableList = &ComdatVariables;
3285 else
3286 // Emit this global variable in a single global symbol section.
3287 VariableList = &GlobalVariables;
3288 CVGlobalVariable CVGV = {.DIGV: DIGV, .GVInfo: GV};
3289 VariableList->emplace_back(Args: std::move(CVGV));
3290 }
3291 }
3292}
3293
3294void CodeViewDebug::collectDebugInfoForGlobals() {
3295 for (const CVGlobalVariable &CVGV : GlobalVariables) {
3296 const DIGlobalVariable *DIGV = CVGV.DIGV;
3297 const DIScope *Scope = DIGV->getScope();
3298 getCompleteTypeIndex(Ty: DIGV->getType());
3299 getFullyQualifiedName(Scope, Name: DIGV->getName());
3300 }
3301
3302 for (const CVGlobalVariable &CVGV : ComdatVariables) {
3303 const DIGlobalVariable *DIGV = CVGV.DIGV;
3304 const DIScope *Scope = DIGV->getScope();
3305 getCompleteTypeIndex(Ty: DIGV->getType());
3306 getFullyQualifiedName(Scope, Name: DIGV->getName());
3307 }
3308}
3309
3310void CodeViewDebug::emitDebugInfoForGlobals() {
3311 // First, emit all globals that are not in a comdat in a single symbol
3312 // substream. MSVC doesn't like it if the substream is empty, so only open
3313 // it if we have at least one global to emit.
3314 switchToDebugSectionForSymbol(GVSym: nullptr);
3315 if (!GlobalVariables.empty() || !StaticConstMembers.empty()) {
3316 OS.AddComment(T: "Symbol subsection for globals");
3317 MCSymbol *EndLabel = beginCVSubsection(Kind: DebugSubsectionKind::Symbols);
3318 emitGlobalVariableList(Globals: GlobalVariables);
3319 emitStaticConstMemberList();
3320 endCVSubsection(EndLabel);
3321 }
3322
3323 // Second, emit each global that is in a comdat into its own .debug$S
3324 // section along with its own symbol substream.
3325 for (const CVGlobalVariable &CVGV : ComdatVariables) {
3326 const GlobalVariable *GV = cast<const GlobalVariable *>(Val: CVGV.GVInfo);
3327 MCSymbol *GVSym = Asm->getSymbol(GV);
3328 OS.AddComment(T: "Symbol subsection for " +
3329 Twine(GlobalValue::dropLLVMManglingEscape(Name: GV->getName())));
3330 switchToDebugSectionForSymbol(GVSym);
3331 MCSymbol *EndLabel = beginCVSubsection(Kind: DebugSubsectionKind::Symbols);
3332 // FIXME: emitDebugInfoForGlobal() doesn't handle DIExpressions.
3333 emitDebugInfoForGlobal(CVGV);
3334 endCVSubsection(EndLabel);
3335 }
3336}
3337
3338void CodeViewDebug::emitDebugInfoForRetainedTypes() {
3339 NamedMDNode *CUs = MMI->getModule()->getNamedMetadata(Name: "llvm.dbg.cu");
3340 for (const MDNode *Node : CUs->operands()) {
3341 for (auto *Ty : cast<DICompileUnit>(Val: Node)->getRetainedTypes()) {
3342 if (DIType *RT = dyn_cast<DIType>(Val: Ty)) {
3343 getTypeIndex(Ty: RT);
3344 // FIXME: Add to global/local DTU list.
3345 }
3346 }
3347 }
3348}
3349
3350// Emit each global variable in the specified array.
3351void CodeViewDebug::emitGlobalVariableList(ArrayRef<CVGlobalVariable> Globals) {
3352 for (const CVGlobalVariable &CVGV : Globals) {
3353 // FIXME: emitDebugInfoForGlobal() doesn't handle DIExpressions.
3354 emitDebugInfoForGlobal(CVGV);
3355 }
3356}
3357
3358void CodeViewDebug::emitConstantSymbolRecord(const DIType *DTy, APSInt &Value,
3359 const std::string &QualifiedName) {
3360 MCSymbol *SConstantEnd = beginSymbolRecord(SymKind: SymbolKind::S_CONSTANT);
3361 OS.AddComment(T: "Type");
3362 OS.emitInt32(Value: getTypeIndex(Ty: DTy).getIndex());
3363
3364 OS.AddComment(T: "Value");
3365
3366 // Encoded integers shouldn't need more than 10 bytes.
3367 uint8_t Data[10];
3368 BinaryStreamWriter Writer(Data, llvm::endianness::little);
3369 CodeViewRecordIO IO(Writer);
3370 cantFail(Err: IO.mapEncodedInteger(Value));
3371 StringRef SRef((char *)Data, Writer.getOffset());
3372 OS.emitBinaryData(Data: SRef);
3373
3374 OS.AddComment(T: "Name");
3375 emitNullTerminatedSymbolName(OS, S: QualifiedName);
3376 endSymbolRecord(SymEnd: SConstantEnd);
3377}
3378
3379void CodeViewDebug::emitStaticConstMemberList() {
3380 for (const DIDerivedType *DTy : StaticConstMembers) {
3381 const DIScope *Scope = DTy->getScope();
3382
3383 APSInt Value;
3384 if (const ConstantInt *CI =
3385 dyn_cast_or_null<ConstantInt>(Val: DTy->getConstant()))
3386 Value = APSInt(CI->getValue(),
3387 DebugHandlerBase::isUnsignedDIType(Ty: DTy->getBaseType()));
3388 else if (const ConstantFP *CFP =
3389 dyn_cast_or_null<ConstantFP>(Val: DTy->getConstant()))
3390 Value = APSInt(CFP->getValueAPF().bitcastToAPInt(), true);
3391 else
3392 llvm_unreachable("cannot emit a constant without a value");
3393
3394 emitConstantSymbolRecord(DTy: DTy->getBaseType(), Value,
3395 QualifiedName: getFullyQualifiedName(Scope, Name: DTy->getName()));
3396 }
3397}
3398
3399static bool isFloatDIType(const DIType *Ty) {
3400 if (isa<DICompositeType>(Val: Ty))
3401 return false;
3402
3403 if (auto *DTy = dyn_cast<DIDerivedType>(Val: Ty)) {
3404 dwarf::Tag T = (dwarf::Tag)Ty->getTag();
3405 if (T == dwarf::DW_TAG_pointer_type ||
3406 T == dwarf::DW_TAG_ptr_to_member_type ||
3407 T == dwarf::DW_TAG_reference_type ||
3408 T == dwarf::DW_TAG_rvalue_reference_type)
3409 return false;
3410 assert(DTy->getBaseType() && "Expected valid base type");
3411 return isFloatDIType(Ty: DTy->getBaseType());
3412 }
3413
3414 auto *BTy = cast<DIBasicType>(Val: Ty);
3415 return (BTy->getEncoding() == dwarf::DW_ATE_float);
3416}
3417
3418void CodeViewDebug::emitDebugInfoForGlobal(const CVGlobalVariable &CVGV) {
3419 const DIGlobalVariable *DIGV = CVGV.DIGV;
3420
3421 const DIScope *Scope = DIGV->getScope();
3422 // For static data members, get the scope from the declaration.
3423 if (const auto *MemberDecl = dyn_cast_or_null<DIDerivedType>(
3424 Val: DIGV->getRawStaticDataMemberDeclaration()))
3425 Scope = MemberDecl->getScope();
3426 // For static local variables and Fortran, the scoping portion is elided
3427 // in its name so that we can reference the variable in the command line
3428 // of the VS debugger.
3429 std::string QualifiedName =
3430 (moduleIsInFortran() || (Scope && isa<DILocalScope>(Val: Scope)))
3431 ? std::string(DIGV->getName())
3432 : getFullyQualifiedName(Scope, Name: DIGV->getName());
3433
3434 if (const GlobalVariable *GV =
3435 dyn_cast_if_present<const GlobalVariable *>(Val: CVGV.GVInfo)) {
3436 // DataSym record, see SymbolRecord.h for more info. Thread local data
3437 // happens to have the same format as global data.
3438 MCSymbol *GVSym = Asm->getSymbol(GV);
3439 SymbolKind DataSym = GV->isThreadLocal()
3440 ? (DIGV->isLocalToUnit() ? SymbolKind::S_LTHREAD32
3441 : SymbolKind::S_GTHREAD32)
3442 : (DIGV->isLocalToUnit() ? SymbolKind::S_LDATA32
3443 : SymbolKind::S_GDATA32);
3444 MCSymbol *DataEnd = beginSymbolRecord(SymKind: DataSym);
3445 OS.AddComment(T: "Type");
3446 OS.emitInt32(Value: getCompleteTypeIndex(Ty: DIGV->getType()).getIndex());
3447 OS.AddComment(T: "DataOffset");
3448
3449 // Use the offset seen while collecting info on globals.
3450 uint64_t Offset = CVGlobalVariableOffsets.lookup(Val: DIGV);
3451 OS.emitCOFFSecRel32(Symbol: GVSym, Offset);
3452
3453 OS.AddComment(T: "Segment");
3454 OS.emitCOFFSectionIndex(Symbol: GVSym);
3455 OS.AddComment(T: "Name");
3456 const unsigned LengthOfDataRecord = 12;
3457 emitNullTerminatedSymbolName(OS, S: QualifiedName, MaxFixedRecordLength: LengthOfDataRecord);
3458 endSymbolRecord(SymEnd: DataEnd);
3459 } else {
3460 const DIExpression *DIE = cast<const DIExpression *>(Val: CVGV.GVInfo);
3461 assert(DIE->isConstant() &&
3462 "Global constant variables must contain a constant expression.");
3463
3464 // Use unsigned for floats.
3465 bool isUnsigned = isFloatDIType(Ty: DIGV->getType())
3466 ? true
3467 : DebugHandlerBase::isUnsignedDIType(Ty: DIGV->getType());
3468 APSInt Value(APInt(/*BitWidth=*/64, DIE->getElement(I: 1)), isUnsigned);
3469 emitConstantSymbolRecord(DTy: DIGV->getType(), Value, QualifiedName);
3470 }
3471}
3472
3473void forEachJumpTableBranch(
3474 const MachineFunction *MF, bool isThumb,
3475 const std::function<void(const MachineJumpTableInfo &, const MachineInstr &,
3476 int64_t)> &Callback) {
3477 auto JTI = MF->getJumpTableInfo();
3478 if (JTI && !JTI->isEmpty()) {
3479#ifndef NDEBUG
3480 auto UsedJTs = llvm::SmallBitVector(JTI->getJumpTables().size());
3481#endif
3482 for (const auto &MBB : *MF) {
3483 // Search for indirect branches...
3484 const auto LastMI = MBB.getFirstTerminator();
3485 if (LastMI != MBB.end() && LastMI->isIndirectBranch()) {
3486 if (isThumb) {
3487 // ... that directly use jump table operands.
3488 // NOTE: ARM uses pattern matching to lower its BR_JT SDNode to
3489 // machine instructions, hence inserting a JUMP_TABLE_DEBUG_INFO node
3490 // interferes with this process *but* the resulting pseudo-instruction
3491 // uses a Jump Table operand, so extract the jump table index directly
3492 // from that.
3493 for (const auto &MO : LastMI->operands()) {
3494 if (MO.isJTI()) {
3495 unsigned Index = MO.getIndex();
3496#ifndef NDEBUG
3497 UsedJTs.set(Index);
3498#endif
3499 Callback(*JTI, *LastMI, Index);
3500 break;
3501 }
3502 }
3503 } else {
3504 // ... that have jump table debug info.
3505 // NOTE: The debug info is inserted as a JUMP_TABLE_DEBUG_INFO node
3506 // when lowering the BR_JT SDNode to an indirect branch.
3507 for (auto I = MBB.instr_rbegin(), E = MBB.instr_rend(); I != E; ++I) {
3508 if (I->isJumpTableDebugInfo()) {
3509 unsigned Index = I->getOperand(i: 0).getImm();
3510#ifndef NDEBUG
3511 UsedJTs.set(Index);
3512#endif
3513 Callback(*JTI, *LastMI, Index);
3514 break;
3515 }
3516 }
3517 }
3518 }
3519 }
3520#ifndef NDEBUG
3521 assert(UsedJTs.all() &&
3522 "Some of jump tables were not used in a debug info instruction");
3523#endif
3524 }
3525}
3526
3527void CodeViewDebug::discoverJumpTableBranches(const MachineFunction *MF,
3528 bool isThumb) {
3529 forEachJumpTableBranch(
3530 MF, isThumb,
3531 Callback: [this](const MachineJumpTableInfo &, const MachineInstr &BranchMI,
3532 int64_t) { requestLabelBeforeInsn(MI: &BranchMI); });
3533}
3534
3535void CodeViewDebug::collectDebugInfoForJumpTables(const MachineFunction *MF,
3536 bool isThumb) {
3537 forEachJumpTableBranch(
3538 MF, isThumb,
3539 Callback: [this, MF](const MachineJumpTableInfo &JTI, const MachineInstr &BranchMI,
3540 int64_t JumpTableIndex) {
3541 // For label-difference jump tables, find the base expression.
3542 // Otherwise the jump table uses an absolute address (so no base
3543 // is required).
3544 const MCSymbol *Base;
3545 uint64_t BaseOffset = 0;
3546 const MCSymbol *Branch = getLabelBeforeInsn(MI: &BranchMI);
3547 JumpTableEntrySize EntrySize;
3548 switch (JTI.getEntryKind()) {
3549 case MachineJumpTableInfo::EK_Custom32:
3550 case MachineJumpTableInfo::EK_GPRel32BlockAddress:
3551 case MachineJumpTableInfo::EK_GPRel64BlockAddress:
3552 llvm_unreachable(
3553 "EK_Custom32, EK_GPRel32BlockAddress, and "
3554 "EK_GPRel64BlockAddress should never be emitted for COFF");
3555 case MachineJumpTableInfo::EK_BlockAddress:
3556 // Each entry is an absolute address.
3557 EntrySize = JumpTableEntrySize::Pointer;
3558 Base = nullptr;
3559 break;
3560 case MachineJumpTableInfo::EK_Inline:
3561 case MachineJumpTableInfo::EK_LabelDifference32:
3562 case MachineJumpTableInfo::EK_LabelDifference64:
3563 // Ask the AsmPrinter.
3564 std::tie(args&: Base, args&: BaseOffset, args&: Branch, args&: EntrySize) =
3565 Asm->getCodeViewJumpTableInfo(JTI: JumpTableIndex, BranchInstr: &BranchMI, BranchLabel: Branch);
3566 break;
3567 }
3568
3569 CurFn->JumpTables.push_back(
3570 x: {.EntrySize: EntrySize, .Base: Base, .BaseOffset: BaseOffset, .Branch: Branch,
3571 .Table: MF->getJTISymbol(JTI: JumpTableIndex, Ctx&: MMI->getContext()),
3572 .TableSize: JTI.getJumpTables()[JumpTableIndex].MBBs.size()});
3573 });
3574}
3575
3576void CodeViewDebug::emitDebugInfoForJumpTables(const FunctionInfo &FI) {
3577 for (auto JumpTable : FI.JumpTables) {
3578 MCSymbol *JumpTableEnd = beginSymbolRecord(SymKind: SymbolKind::S_ARMSWITCHTABLE);
3579 if (JumpTable.Base) {
3580 OS.AddComment(T: "Base offset");
3581 OS.emitCOFFSecRel32(Symbol: JumpTable.Base, Offset: JumpTable.BaseOffset);
3582 OS.AddComment(T: "Base section index");
3583 OS.emitCOFFSectionIndex(Symbol: JumpTable.Base);
3584 } else {
3585 OS.AddComment(T: "Base offset");
3586 OS.emitInt32(Value: 0);
3587 OS.AddComment(T: "Base section index");
3588 OS.emitInt16(Value: 0);
3589 }
3590 OS.AddComment(T: "Switch type");
3591 OS.emitInt16(Value: static_cast<uint16_t>(JumpTable.EntrySize));
3592 OS.AddComment(T: "Branch offset");
3593 OS.emitCOFFSecRel32(Symbol: JumpTable.Branch, /*Offset=*/0);
3594 OS.AddComment(T: "Table offset");
3595 OS.emitCOFFSecRel32(Symbol: JumpTable.Table, /*Offset=*/0);
3596 OS.AddComment(T: "Branch section index");
3597 OS.emitCOFFSectionIndex(Symbol: JumpTable.Branch);
3598 OS.AddComment(T: "Table section index");
3599 OS.emitCOFFSectionIndex(Symbol: JumpTable.Table);
3600 OS.AddComment(T: "Entries count");
3601 OS.emitInt32(Value: JumpTable.TableSize);
3602 endSymbolRecord(SymEnd: JumpTableEnd);
3603 }
3604}
3605
3606void CodeViewDebug::emitInlinees(
3607 const SmallSet<codeview::TypeIndex, 1> &Inlinees) {
3608 // Divide the list of inlinees into chunks such that each chunk fits within
3609 // one record.
3610 constexpr size_t ChunkSize =
3611 (MaxRecordLength - sizeof(SymbolKind) - sizeof(uint32_t)) /
3612 sizeof(uint32_t);
3613
3614 SmallVector<TypeIndex> SortedInlinees{Inlinees.begin(), Inlinees.end()};
3615 llvm::sort(C&: SortedInlinees);
3616
3617 size_t CurrentIndex = 0;
3618 while (CurrentIndex < SortedInlinees.size()) {
3619 auto Symbol = beginSymbolRecord(SymKind: SymbolKind::S_INLINEES);
3620 auto CurrentChunkSize =
3621 std::min(a: ChunkSize, b: SortedInlinees.size() - CurrentIndex);
3622 OS.AddComment(T: "Count");
3623 OS.emitInt32(Value: CurrentChunkSize);
3624
3625 const size_t CurrentChunkEnd = CurrentIndex + CurrentChunkSize;
3626 for (; CurrentIndex < CurrentChunkEnd; ++CurrentIndex) {
3627 OS.AddComment(T: "Inlinee");
3628 OS.emitInt32(Value: SortedInlinees[CurrentIndex].getIndex());
3629 }
3630 endSymbolRecord(SymEnd: Symbol);
3631 }
3632}
3633