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
573MapDWARFLanguageToCVLang(dwarf::SourceLanguageName DWLName) {
574 switch (DWLName) {
575 case dwarf::DW_LNAME_C:
576 return SourceLanguage::C;
577 case dwarf::DW_LNAME_C_plus_plus:
578 return SourceLanguage::Cpp;
579 case dwarf::DW_LNAME_Fortran:
580 return SourceLanguage::Fortran;
581 case dwarf::DW_LNAME_Pascal:
582 return SourceLanguage::Pascal;
583 case dwarf::DW_LNAME_Cobol:
584 return SourceLanguage::Cobol;
585 case dwarf::DW_LNAME_Java:
586 return SourceLanguage::Java;
587 case dwarf::DW_LNAME_D:
588 return SourceLanguage::D;
589 case dwarf::DW_LNAME_Swift:
590 return SourceLanguage::Swift;
591 case dwarf::DW_LNAME_Rust:
592 return SourceLanguage::Rust;
593 case dwarf::DW_LNAME_ObjC:
594 return SourceLanguage::ObjC;
595 case dwarf::DW_LNAME_ObjC_plus_plus:
596 return SourceLanguage::ObjCpp;
597 default:
598 // There's no CodeView representation for this language, and CV doesn't
599 // have an "unknown" option for the language field, so we'll use MASM,
600 // as it's very low level.
601 return SourceLanguage::Masm;
602 }
603}
604
605static SourceLanguage MapDWARFLanguageToCVLang(dwarf::SourceLanguage DWLang) {
606 auto MaybeLName = dwarf::toDW_LNAME(language: DWLang);
607 if (!MaybeLName)
608 return MapDWARFLanguageToCVLang(DWLName: static_cast<dwarf::SourceLanguageName>(0));
609
610 return MapDWARFLanguageToCVLang(DWLName: MaybeLName->first);
611}
612
613void CodeViewDebug::beginModule(Module *M) {
614 // If COFF debug section is not available, skip any debug info related stuff.
615 if (!Asm->getObjFileLowering().getCOFFDebugSymbolsSection()) {
616 Asm = nullptr;
617 return;
618 }
619
620 CompilerInfoAsm = Asm;
621 TheCPU = mapArchToCVCPUType(Type: M->getTargetTriple().getArch());
622
623 // Get the current source language.
624 const MDNode *Node;
625 if (Asm->hasDebugInfo()) {
626 Node = *M->debug_compile_units_begin();
627 } else {
628 // When emitting only compiler information, we may have only NoDebug CUs,
629 // which would be skipped by debug_compile_units_begin.
630 NamedMDNode *CUs = MMI->getModule()->getNamedMetadata(Name: "llvm.dbg.cu");
631 if (CUs->operands().empty()) {
632 Asm = nullptr;
633 return;
634 }
635 Node = *CUs->operands().begin();
636 }
637
638 TheCU = cast<DICompileUnit>(Val: Node);
639 DISourceLanguageName Lang = TheCU->getSourceLanguage();
640 CurrentSourceLanguage =
641 Lang.hasVersionedName()
642 ? MapDWARFLanguageToCVLang(
643 DWLName: static_cast<dwarf::SourceLanguageName>(Lang.getName()))
644 : MapDWARFLanguageToCVLang(
645 DWLang: static_cast<dwarf::SourceLanguage>(Lang.getName()));
646 if (!M->getCodeViewFlag() ||
647 TheCU->getEmissionKind() == DICompileUnit::NoDebug) {
648 Asm = nullptr;
649 return;
650 }
651
652 collectGlobalVariableInfo();
653
654 // Check if we should emit type record hashes.
655 ConstantInt *GH =
656 mdconst::extract_or_null<ConstantInt>(MD: M->getModuleFlag(Key: "CodeViewGHash"));
657 EmitDebugGlobalHashes = GH && !GH->isZero();
658}
659
660void CodeViewDebug::endModule() {
661 if (!CompilerInfoAsm)
662 return;
663
664 // The COFF .debug$S section consists of several subsections, each starting
665 // with a 4-byte control code (e.g. 0xF1, 0xF2, etc) and then a 4-byte length
666 // of the payload followed by the payload itself. The subsections are 4-byte
667 // aligned.
668
669 // Use the generic .debug$S section, and make a subsection for all the inlined
670 // subprograms.
671 switchToDebugSectionForSymbol(GVSym: nullptr);
672
673 MCSymbol *CompilerInfo = beginCVSubsection(Kind: DebugSubsectionKind::Symbols);
674 emitObjName();
675 emitCompilerInformation();
676 endCVSubsection(EndLabel: CompilerInfo);
677 if (!Asm)
678 return;
679
680 emitSecureHotPatchInformation();
681
682 emitInlineeLinesSubsection();
683
684 // Emit per-function debug information.
685 for (auto &P : FnDebugInfo)
686 if (!P.first->isDeclarationForLinker())
687 emitDebugInfoForFunction(GV: P.first, FI&: *P.second);
688
689 // Get types used by globals without emitting anything.
690 // This is meant to collect all static const data members so they can be
691 // emitted as globals.
692 collectDebugInfoForGlobals();
693
694 // Emit retained types.
695 emitDebugInfoForRetainedTypes();
696
697 // Emit global variable debug information.
698 setCurrentSubprogram(nullptr);
699 emitDebugInfoForGlobals();
700
701 // Switch back to the generic .debug$S section after potentially processing
702 // comdat symbol sections.
703 switchToDebugSectionForSymbol(GVSym: nullptr);
704
705 // Emit UDT records for any types used by global variables.
706 if (!GlobalUDTs.empty()) {
707 MCSymbol *SymbolsEnd = beginCVSubsection(Kind: DebugSubsectionKind::Symbols);
708 emitDebugInfoForUDTs(UDTs: GlobalUDTs);
709 endCVSubsection(EndLabel: SymbolsEnd);
710 }
711
712 // This subsection holds a file index to offset in string table table.
713 OS.AddComment(T: "File index to string table offset subsection");
714 OS.emitCVFileChecksumsDirective();
715
716 // This subsection holds the string table.
717 OS.AddComment(T: "String table");
718 OS.emitCVStringTableDirective();
719
720 // Emit S_BUILDINFO, which points to LF_BUILDINFO. Put this in its own symbol
721 // subsection in the generic .debug$S section at the end. There is no
722 // particular reason for this ordering other than to match MSVC.
723 emitBuildInfo();
724
725 // Emit type information and hashes last, so that any types we translate while
726 // emitting function info are included.
727 emitTypeInformation();
728
729 if (EmitDebugGlobalHashes)
730 emitTypeGlobalHashes();
731
732 clear();
733}
734
735static void
736emitNullTerminatedSymbolName(MCStreamer &OS, StringRef S,
737 unsigned MaxFixedRecordLength = 0xF00) {
738 // The maximum CV record length is 0xFF00. Most of the strings we emit appear
739 // after a fixed length portion of the record. The fixed length portion should
740 // always be less than 0xF00 (3840) bytes, so truncate the string so that the
741 // overall record size is less than the maximum allowed.
742 SmallString<32> NullTerminatedString(
743 S.take_front(N: MaxRecordLength - MaxFixedRecordLength - 1));
744 NullTerminatedString.push_back(Elt: '\0');
745 OS.emitBytes(Data: NullTerminatedString);
746}
747
748void CodeViewDebug::emitTypeInformation() {
749 if (TypeTable.empty())
750 return;
751
752 // Start the .debug$T or .debug$P section with 0x4.
753 OS.switchSection(Section: Asm->getObjFileLowering().getCOFFDebugTypesSection());
754 emitCodeViewMagicVersion();
755
756 TypeTableCollection Table(TypeTable.records());
757 TypeVisitorCallbackPipeline Pipeline;
758
759 // To emit type record using Codeview MCStreamer adapter
760 CVMCAdapter CVMCOS(OS, Table);
761 TypeRecordMapping typeMapping(CVMCOS);
762 Pipeline.addCallbackToPipeline(Callbacks&: typeMapping);
763
764 std::optional<TypeIndex> B = Table.getFirst();
765 while (B) {
766 // This will fail if the record data is invalid.
767 CVType Record = Table.getType(Index: *B);
768
769 Error E = codeview::visitTypeRecord(Record, Index: *B, Callbacks&: Pipeline);
770
771 if (E) {
772 logAllUnhandledErrors(E: std::move(E), OS&: errs(), ErrorBanner: "error: ");
773 llvm_unreachable("produced malformed type record");
774 }
775
776 B = Table.getNext(Prev: *B);
777 }
778}
779
780void CodeViewDebug::emitTypeGlobalHashes() {
781 if (TypeTable.empty())
782 return;
783
784 // Start the .debug$H section with the version and hash algorithm, currently
785 // hardcoded to version 0, SHA1.
786 OS.switchSection(Section: Asm->getObjFileLowering().getCOFFGlobalTypeHashesSection());
787
788 OS.emitValueToAlignment(Alignment: Align(4));
789 OS.AddComment(T: "Magic");
790 OS.emitInt32(Value: COFF::DEBUG_HASHES_SECTION_MAGIC);
791 OS.AddComment(T: "Section Version");
792 OS.emitInt16(Value: 0);
793 OS.AddComment(T: "Hash Algorithm");
794 OS.emitInt16(Value: uint16_t(GlobalTypeHashAlg::BLAKE3));
795
796 TypeIndex TI(TypeIndex::FirstNonSimpleIndex);
797 for (const auto &GHR : TypeTable.hashes()) {
798 if (OS.isVerboseAsm()) {
799 // Emit an EOL-comment describing which TypeIndex this hash corresponds
800 // to, as well as the stringified SHA1 hash.
801 SmallString<32> Comment;
802 raw_svector_ostream CommentOS(Comment);
803 CommentOS << formatv(Fmt: "{0:X+} [{1}]", Vals: TI.getIndex(), Vals: GHR);
804 OS.AddComment(T: Comment);
805 ++TI;
806 }
807 assert(GHR.Hash.size() == 8);
808 StringRef S(reinterpret_cast<const char *>(GHR.Hash.data()),
809 GHR.Hash.size());
810 OS.emitBinaryData(Data: S);
811 }
812}
813
814void CodeViewDebug::emitObjName() {
815 MCSymbol *CompilerEnd = beginSymbolRecord(Kind: SymbolKind::S_OBJNAME);
816
817 StringRef PathRef(CompilerInfoAsm->TM.Options.ObjectFilenameForDebug);
818 llvm::SmallString<256> PathStore(PathRef);
819
820 if (PathRef.empty() || PathRef == "-") {
821 // Don't emit the filename if we're writing to stdout or to /dev/null.
822 PathRef = {};
823 } else {
824 PathRef = PathStore;
825 }
826
827 OS.AddComment(T: "Signature");
828 OS.emitIntValue(Value: 0, Size: 4);
829
830 OS.AddComment(T: "Object name");
831 emitNullTerminatedSymbolName(OS, S: PathRef);
832
833 endSymbolRecord(SymEnd: CompilerEnd);
834}
835
836void CodeViewDebug::emitSecureHotPatchInformation() {
837 MCSymbol *hotPatchInfo = nullptr;
838
839 for (const auto &F : MMI->getModule()->functions()) {
840 if (!F.isDeclarationForLinker() &&
841 F.hasFnAttribute(Kind: "marked_for_windows_hot_patching")) {
842 if (hotPatchInfo == nullptr)
843 hotPatchInfo = beginCVSubsection(Kind: DebugSubsectionKind::Symbols);
844 MCSymbol *HotPatchEnd = beginSymbolRecord(Kind: SymbolKind::S_HOTPATCHFUNC);
845 auto *SP = F.getSubprogram();
846 OS.AddComment(T: "Function");
847 OS.emitInt32(Value: getFuncIdForSubprogram(SP).getIndex());
848 OS.AddComment(T: "Name");
849 emitNullTerminatedSymbolName(OS, S: F.getName());
850 endSymbolRecord(SymEnd: HotPatchEnd);
851 }
852 }
853
854 if (hotPatchInfo != nullptr)
855 endCVSubsection(EndLabel: hotPatchInfo);
856}
857
858namespace {
859struct Version {
860 int Part[4];
861};
862} // end anonymous namespace
863
864// Takes a StringRef like "clang 4.0.0.0 (other nonsense 123)" and parses out
865// the version number.
866static Version parseVersion(StringRef Name) {
867 Version V = {.Part: {0}};
868 int N = 0;
869 for (const char C : Name) {
870 if (isdigit(C)) {
871 V.Part[N] *= 10;
872 V.Part[N] += C - '0';
873 V.Part[N] =
874 std::min<int>(a: V.Part[N], b: std::numeric_limits<uint16_t>::max());
875 } else if (C == '.') {
876 ++N;
877 if (N >= 4)
878 return V;
879 } else if (N > 0)
880 return V;
881 }
882 return V;
883}
884
885void CodeViewDebug::emitCompilerInformation() {
886 MCSymbol *CompilerEnd = beginSymbolRecord(Kind: SymbolKind::S_COMPILE3);
887 uint32_t Flags = 0;
888
889 // The low byte of the flags indicates the source language.
890 Flags = CurrentSourceLanguage;
891 // TODO: Figure out which other flags need to be set.
892 if (MMI->getModule()->getProfileSummary(/*IsCS*/ false) != nullptr) {
893 Flags |= static_cast<uint32_t>(CompileSym3Flags::PGO);
894 }
895 using ArchType = llvm::Triple::ArchType;
896 ArchType Arch = MMI->getModule()->getTargetTriple().getArch();
897 if (CompilerInfoAsm->TM.Options.Hotpatch || Arch == ArchType::thumb ||
898 Arch == ArchType::aarch64) {
899 Flags |= static_cast<uint32_t>(CompileSym3Flags::HotPatch);
900 }
901
902 OS.AddComment(T: "Flags and language");
903 OS.emitInt32(Value: Flags);
904
905 OS.AddComment(T: "CPUType");
906 OS.emitInt16(Value: static_cast<uint64_t>(TheCPU));
907
908 StringRef CompilerVersion = "0";
909 if (TheCU)
910 CompilerVersion = TheCU->getProducer();
911
912 Version FrontVer = parseVersion(Name: CompilerVersion);
913 OS.AddComment(T: "Frontend version");
914 for (int N : FrontVer.Part) {
915 OS.emitInt16(Value: N);
916 }
917
918 // Some Microsoft tools, like Binscope, expect a backend version number of at
919 // least 8.something, so we'll coerce the LLVM version into a form that
920 // guarantees it'll be big enough without really lying about the version.
921 int Major = 1000 * LLVM_VERSION_MAJOR +
922 10 * LLVM_VERSION_MINOR +
923 LLVM_VERSION_PATCH;
924 // Clamp it for builds that use unusually large version numbers.
925 Major = std::min<int>(a: Major, b: std::numeric_limits<uint16_t>::max());
926 Version BackVer = {.Part: { Major, 0, 0, 0 }};
927 OS.AddComment(T: "Backend version");
928 for (int N : BackVer.Part)
929 OS.emitInt16(Value: N);
930
931 OS.AddComment(T: "Null-terminated compiler version string");
932 emitNullTerminatedSymbolName(OS, S: CompilerVersion);
933
934 endSymbolRecord(SymEnd: CompilerEnd);
935}
936
937static TypeIndex getStringIdTypeIdx(GlobalTypeTableBuilder &TypeTable,
938 StringRef S) {
939 StringIdRecord SIR(TypeIndex(0x0), S);
940 return TypeTable.writeLeafType(Record&: SIR);
941}
942
943void CodeViewDebug::emitBuildInfo() {
944 // First, make LF_BUILDINFO. It's a sequence of strings with various bits of
945 // build info. The known prefix is:
946 // - Absolute path of current directory
947 // - Compiler path
948 // - Main source file path, relative to CWD or absolute
949 // - Type server PDB file
950 // - Canonical compiler command line
951 // If frontend and backend compilation are separated (think llc or LTO), it's
952 // not clear if the compiler path should refer to the executable for the
953 // frontend or the backend. Leave it blank for now.
954 TypeIndex BuildInfoArgs[BuildInfoRecord::MaxArgs] = {};
955 NamedMDNode *CUs = MMI->getModule()->getNamedMetadata(Name: "llvm.dbg.cu");
956 const MDNode *Node = *CUs->operands().begin(); // FIXME: Multiple CUs.
957 const auto *CU = cast<DICompileUnit>(Val: Node);
958 const DIFile *MainSourceFile = CU->getFile();
959 BuildInfoArgs[BuildInfoRecord::CurrentDirectory] =
960 getStringIdTypeIdx(TypeTable, S: MainSourceFile->getDirectory());
961 BuildInfoArgs[BuildInfoRecord::SourceFile] =
962 getStringIdTypeIdx(TypeTable, S: MainSourceFile->getFilename());
963 // FIXME: PDB is intentionally blank unless we implement /Zi type servers.
964 BuildInfoArgs[BuildInfoRecord::TypeServerPDB] =
965 getStringIdTypeIdx(TypeTable, S: "");
966 BuildInfoArgs[BuildInfoRecord::BuildTool] =
967 getStringIdTypeIdx(TypeTable, S: Asm->TM.Options.MCOptions.Argv0);
968 BuildInfoArgs[BuildInfoRecord::CommandLine] = getStringIdTypeIdx(
969 TypeTable, S: Asm->TM.Options.MCOptions.CommandlineArgs);
970
971 BuildInfoRecord BIR(BuildInfoArgs);
972 TypeIndex BuildInfoIndex = TypeTable.writeLeafType(Record&: BIR);
973
974 // Make a new .debug$S subsection for the S_BUILDINFO record, which points
975 // from the module symbols into the type stream.
976 MCSymbol *BISubsecEnd = beginCVSubsection(Kind: DebugSubsectionKind::Symbols);
977 MCSymbol *BIEnd = beginSymbolRecord(Kind: SymbolKind::S_BUILDINFO);
978 OS.AddComment(T: "LF_BUILDINFO index");
979 OS.emitInt32(Value: BuildInfoIndex.getIndex());
980 endSymbolRecord(SymEnd: BIEnd);
981 endCVSubsection(EndLabel: BISubsecEnd);
982}
983
984void CodeViewDebug::emitInlineeLinesSubsection() {
985 if (InlinedSubprograms.empty())
986 return;
987
988 OS.AddComment(T: "Inlinee lines subsection");
989 MCSymbol *InlineEnd = beginCVSubsection(Kind: DebugSubsectionKind::InlineeLines);
990
991 // We emit the checksum info for files. This is used by debuggers to
992 // determine if a pdb matches the source before loading it. Visual Studio,
993 // for instance, will display a warning that the breakpoints are not valid if
994 // the pdb does not match the source.
995 OS.AddComment(T: "Inlinee lines signature");
996 OS.emitInt32(Value: unsigned(InlineeLinesSignature::Normal));
997
998 for (const DISubprogram *SP : InlinedSubprograms) {
999 assert(TypeIndices.count({SP, nullptr}));
1000 TypeIndex InlineeIdx = TypeIndices[{SP, nullptr}];
1001
1002 OS.addBlankLine();
1003 unsigned FileId = maybeRecordFile(F: SP->getFile());
1004 OS.AddComment(T: "Inlined function " + SP->getName() + " starts at " +
1005 SP->getFilename() + Twine(':') + Twine(SP->getLine()));
1006 OS.addBlankLine();
1007 OS.AddComment(T: "Type index of inlined function");
1008 OS.emitInt32(Value: InlineeIdx.getIndex());
1009 OS.AddComment(T: "Offset into filechecksum table");
1010 OS.emitCVFileChecksumOffsetDirective(FileNo: FileId);
1011 OS.AddComment(T: "Starting line number");
1012 OS.emitInt32(Value: SP->getLine());
1013 }
1014
1015 endCVSubsection(EndLabel: InlineEnd);
1016}
1017
1018void CodeViewDebug::emitInlinedCallSite(const FunctionInfo &FI,
1019 const DILocation *InlinedAt,
1020 const InlineSite &Site) {
1021 assert(TypeIndices.count({Site.Inlinee, nullptr}));
1022 TypeIndex InlineeIdx = TypeIndices[{Site.Inlinee, nullptr}];
1023
1024 // SymbolRecord
1025 MCSymbol *InlineEnd = beginSymbolRecord(Kind: SymbolKind::S_INLINESITE);
1026
1027 OS.AddComment(T: "PtrParent");
1028 OS.emitInt32(Value: 0);
1029 OS.AddComment(T: "PtrEnd");
1030 OS.emitInt32(Value: 0);
1031 OS.AddComment(T: "Inlinee type index");
1032 OS.emitInt32(Value: InlineeIdx.getIndex());
1033
1034 unsigned FileId = maybeRecordFile(F: Site.Inlinee->getFile());
1035 unsigned StartLineNum = Site.Inlinee->getLine();
1036
1037 OS.emitCVInlineLinetableDirective(PrimaryFunctionId: Site.SiteFuncId, SourceFileId: FileId, SourceLineNum: StartLineNum,
1038 FnStartSym: FI.Begin, FnEndSym: FI.End);
1039
1040 endSymbolRecord(SymEnd: InlineEnd);
1041
1042 emitLocalVariableList(FI, Locals: Site.InlinedLocals);
1043
1044 // Recurse on child inlined call sites before closing the scope.
1045 for (const DILocation *ChildSite : Site.ChildSites) {
1046 auto I = FI.InlineSites.find(x: ChildSite);
1047 assert(I != FI.InlineSites.end() &&
1048 "child site not in function inline site map");
1049 emitInlinedCallSite(FI, InlinedAt: ChildSite, Site: I->second);
1050 }
1051
1052 // Close the scope.
1053 emitEndSymbolRecord(EndKind: SymbolKind::S_INLINESITE_END);
1054}
1055
1056void CodeViewDebug::switchToDebugSectionForSymbol(const MCSymbol *GVSym) {
1057 // If we have a symbol, it may be in a section that is COMDAT. If so, find the
1058 // comdat key. A section may be comdat because of -ffunction-sections or
1059 // because it is comdat in the IR.
1060 MCSectionCOFF *GVSec =
1061 GVSym ? static_cast<MCSectionCOFF *>(&GVSym->getSection()) : nullptr;
1062 const MCSymbol *KeySym = GVSec ? GVSec->getCOMDATSymbol() : nullptr;
1063
1064 auto *DebugSec = static_cast<MCSectionCOFF *>(
1065 CompilerInfoAsm->getObjFileLowering().getCOFFDebugSymbolsSection());
1066 DebugSec = OS.getContext().getAssociativeCOFFSection(Sec: DebugSec, KeySym);
1067
1068 OS.switchSection(Section: DebugSec);
1069
1070 // Emit the magic version number if this is the first time we've switched to
1071 // this section.
1072 if (ComdatDebugSections.insert(V: DebugSec).second)
1073 emitCodeViewMagicVersion();
1074}
1075
1076// Emit an S_THUNK32/S_END symbol pair for a thunk routine.
1077// The only supported thunk ordinal is currently the standard type.
1078void CodeViewDebug::emitDebugInfoForThunk(const Function *GV,
1079 FunctionInfo &FI,
1080 const MCSymbol *Fn) {
1081 std::string FuncName =
1082 std::string(GlobalValue::dropLLVMManglingEscape(Name: GV->getName()));
1083 const ThunkOrdinal ordinal = ThunkOrdinal::Standard; // Only supported kind.
1084
1085 OS.AddComment(T: "Symbol subsection for " + Twine(FuncName));
1086 MCSymbol *SymbolsEnd = beginCVSubsection(Kind: DebugSubsectionKind::Symbols);
1087
1088 // Emit S_THUNK32
1089 MCSymbol *ThunkRecordEnd = beginSymbolRecord(Kind: SymbolKind::S_THUNK32);
1090 OS.AddComment(T: "PtrParent");
1091 OS.emitInt32(Value: 0);
1092 OS.AddComment(T: "PtrEnd");
1093 OS.emitInt32(Value: 0);
1094 OS.AddComment(T: "PtrNext");
1095 OS.emitInt32(Value: 0);
1096 OS.AddComment(T: "Thunk section relative address");
1097 OS.emitCOFFSecRel32(Symbol: Fn, /*Offset=*/0);
1098 OS.AddComment(T: "Thunk section index");
1099 OS.emitCOFFSectionIndex(Symbol: Fn);
1100 OS.AddComment(T: "Code size");
1101 OS.emitAbsoluteSymbolDiff(Hi: FI.End, Lo: Fn, Size: 2);
1102 OS.AddComment(T: "Ordinal");
1103 OS.emitInt8(Value: unsigned(ordinal));
1104 OS.AddComment(T: "Function name");
1105 emitNullTerminatedSymbolName(OS, S: FuncName);
1106 // Additional fields specific to the thunk ordinal would go here.
1107 endSymbolRecord(SymEnd: ThunkRecordEnd);
1108
1109 // Local variables/inlined routines are purposely omitted here. The point of
1110 // marking this as a thunk is so Visual Studio will NOT stop in this routine.
1111
1112 // Emit S_PROC_ID_END
1113 emitEndSymbolRecord(EndKind: SymbolKind::S_PROC_ID_END);
1114
1115 endCVSubsection(EndLabel: SymbolsEnd);
1116}
1117
1118void CodeViewDebug::emitDebugInfoForFunction(const Function *GV,
1119 FunctionInfo &FI) {
1120 // For each function there is a separate subsection which holds the PC to
1121 // file:line table.
1122 const MCSymbol *Fn = Asm->getSymbol(GV);
1123 assert(Fn);
1124
1125 // Switch to the to a comdat section, if appropriate.
1126 switchToDebugSectionForSymbol(GVSym: Fn);
1127
1128 std::string FuncName;
1129 auto *SP = GV->getSubprogram();
1130 assert(SP);
1131 setCurrentSubprogram(SP);
1132
1133 if (SP->isThunk()) {
1134 emitDebugInfoForThunk(GV, FI, Fn);
1135 return;
1136 }
1137
1138 // If we have a display name, build the fully qualified name by walking the
1139 // chain of scopes.
1140 if (!SP->getName().empty())
1141 FuncName = getFullyQualifiedName(Scope: SP->getScope(), Name: SP->getName());
1142
1143 // If our DISubprogram name is empty, use the mangled name.
1144 if (FuncName.empty())
1145 FuncName = std::string(GlobalValue::dropLLVMManglingEscape(Name: GV->getName()));
1146
1147 // Emit FPO data, but only on 32-bit x86. No other platforms use it.
1148 if (MMI->getModule()->getTargetTriple().getArch() == Triple::x86)
1149 OS.emitCVFPOData(ProcSym: Fn);
1150
1151 // Emit a symbol subsection, required by VS2012+ to find function boundaries.
1152 OS.AddComment(T: "Symbol subsection for " + Twine(FuncName));
1153 MCSymbol *SymbolsEnd = beginCVSubsection(Kind: DebugSubsectionKind::Symbols);
1154 {
1155 SymbolKind ProcKind = GV->hasLocalLinkage() ? SymbolKind::S_LPROC32_ID
1156 : SymbolKind::S_GPROC32_ID;
1157 MCSymbol *ProcRecordEnd = beginSymbolRecord(Kind: ProcKind);
1158
1159 // These fields are filled in by tools like CVPACK which run after the fact.
1160 OS.AddComment(T: "PtrParent");
1161 OS.emitInt32(Value: 0);
1162 OS.AddComment(T: "PtrEnd");
1163 OS.emitInt32(Value: 0);
1164 OS.AddComment(T: "PtrNext");
1165 OS.emitInt32(Value: 0);
1166 // This is the important bit that tells the debugger where the function
1167 // code is located and what's its size:
1168 OS.AddComment(T: "Code size");
1169 OS.emitAbsoluteSymbolDiff(Hi: FI.End, Lo: Fn, Size: 4);
1170 OS.AddComment(T: "Offset after prologue");
1171 OS.emitInt32(Value: 0);
1172 OS.AddComment(T: "Offset before epilogue");
1173 OS.emitInt32(Value: 0);
1174 OS.AddComment(T: "Function type index");
1175 OS.emitInt32(Value: getFuncIdForSubprogram(SP: GV->getSubprogram()).getIndex());
1176 OS.AddComment(T: "Function section relative address");
1177 OS.emitCOFFSecRel32(Symbol: Fn, /*Offset=*/0);
1178 OS.AddComment(T: "Function section index");
1179 OS.emitCOFFSectionIndex(Symbol: Fn);
1180 OS.AddComment(T: "Flags");
1181 ProcSymFlags ProcFlags = ProcSymFlags::HasOptimizedDebugInfo;
1182 if (FI.HasFramePointer)
1183 ProcFlags |= ProcSymFlags::HasFP;
1184 if (GV->hasFnAttribute(Kind: Attribute::NoReturn))
1185 ProcFlags |= ProcSymFlags::IsNoReturn;
1186 if (GV->hasFnAttribute(Kind: Attribute::NoInline))
1187 ProcFlags |= ProcSymFlags::IsNoInline;
1188 OS.emitInt8(Value: static_cast<uint8_t>(ProcFlags));
1189 // Emit the function display name as a null-terminated string.
1190 OS.AddComment(T: "Function name");
1191 // Truncate the name so we won't overflow the record length field.
1192 emitNullTerminatedSymbolName(OS, S: FuncName);
1193 endSymbolRecord(SymEnd: ProcRecordEnd);
1194
1195 MCSymbol *FrameProcEnd = beginSymbolRecord(Kind: SymbolKind::S_FRAMEPROC);
1196 // Subtract out the CSR size since MSVC excludes that and we include it.
1197 OS.AddComment(T: "FrameSize");
1198 OS.emitInt32(Value: FI.FrameSize - FI.CSRSize);
1199 OS.AddComment(T: "Padding");
1200 OS.emitInt32(Value: 0);
1201 OS.AddComment(T: "Offset of padding");
1202 OS.emitInt32(Value: 0);
1203 OS.AddComment(T: "Bytes of callee saved registers");
1204 OS.emitInt32(Value: FI.CSRSize);
1205 OS.AddComment(T: "Exception handler offset");
1206 OS.emitInt32(Value: 0);
1207 OS.AddComment(T: "Exception handler section");
1208 OS.emitInt16(Value: 0);
1209 OS.AddComment(T: "Flags (defines frame register)");
1210 OS.emitInt32(Value: uint32_t(FI.FrameProcOpts));
1211 endSymbolRecord(SymEnd: FrameProcEnd);
1212
1213 emitInlinees(Inlinees: FI.Inlinees);
1214 emitLocalVariableList(FI, Locals: FI.Locals);
1215 emitGlobalVariableList(Globals: FI.Globals);
1216 emitLexicalBlockList(Blocks: FI.ChildBlocks, FI);
1217
1218 // Emit inlined call site information. Only emit functions inlined directly
1219 // into the parent function. We'll emit the other sites recursively as part
1220 // of their parent inline site.
1221 for (const DILocation *InlinedAt : FI.ChildSites) {
1222 auto I = FI.InlineSites.find(x: InlinedAt);
1223 assert(I != FI.InlineSites.end() &&
1224 "child site not in function inline site map");
1225 emitInlinedCallSite(FI, InlinedAt, Site: I->second);
1226 }
1227
1228 for (auto Annot : FI.Annotations) {
1229 MCSymbol *Label = Annot.first;
1230 MDTuple *Strs = cast<MDTuple>(Val: Annot.second);
1231 MCSymbol *AnnotEnd = beginSymbolRecord(Kind: SymbolKind::S_ANNOTATION);
1232 OS.emitCOFFSecRel32(Symbol: Label, /*Offset=*/0);
1233 // FIXME: Make sure we don't overflow the max record size.
1234 OS.emitCOFFSectionIndex(Symbol: Label);
1235 OS.emitInt16(Value: Strs->getNumOperands());
1236 for (Metadata *MD : Strs->operands()) {
1237 // MDStrings are null terminated, so we can do EmitBytes and get the
1238 // nice .asciz directive.
1239 StringRef Str = cast<MDString>(Val: MD)->getString();
1240 assert(Str.data()[Str.size()] == '\0' && "non-nullterminated MDString");
1241 OS.emitBytes(Data: StringRef(Str.data(), Str.size() + 1));
1242 }
1243 endSymbolRecord(SymEnd: AnnotEnd);
1244 }
1245
1246 for (auto HeapAllocSite : FI.HeapAllocSites) {
1247 const MCSymbol *BeginLabel = std::get<0>(t&: HeapAllocSite);
1248 const MCSymbol *EndLabel = std::get<1>(t&: HeapAllocSite);
1249 const DIType *DITy = std::get<2>(t&: HeapAllocSite);
1250 MCSymbol *HeapAllocEnd = beginSymbolRecord(Kind: SymbolKind::S_HEAPALLOCSITE);
1251 OS.AddComment(T: "Call site offset");
1252 OS.emitCOFFSecRel32(Symbol: BeginLabel, /*Offset=*/0);
1253 OS.AddComment(T: "Call site section index");
1254 OS.emitCOFFSectionIndex(Symbol: BeginLabel);
1255 OS.AddComment(T: "Call instruction length");
1256 OS.emitAbsoluteSymbolDiff(Hi: EndLabel, Lo: BeginLabel, Size: 2);
1257 OS.AddComment(T: "Type index");
1258 OS.emitInt32(Value: getCompleteTypeIndex(Ty: DITy).getIndex());
1259 endSymbolRecord(SymEnd: HeapAllocEnd);
1260 }
1261
1262 if (SP != nullptr)
1263 emitDebugInfoForUDTs(UDTs: LocalUDTs);
1264
1265 emitDebugInfoForJumpTables(FI);
1266
1267 // We're done with this function.
1268 emitEndSymbolRecord(EndKind: SymbolKind::S_PROC_ID_END);
1269 }
1270 endCVSubsection(EndLabel: SymbolsEnd);
1271
1272 // We have an assembler directive that takes care of the whole line table.
1273 OS.emitCVLinetableDirective(FunctionId: FI.FuncId, FnStart: Fn, FnEnd: FI.End);
1274}
1275
1276CodeViewDebug::LocalVarDef
1277CodeViewDebug::createDefRangeMem(uint16_t CVRegister, int Offset) {
1278 LocalVarDef DR;
1279 DR.InMemory = -1;
1280 DR.DataOffset = Offset;
1281 assert(DR.DataOffset == Offset && "truncation");
1282 DR.IsSubfield = 0;
1283 DR.StructOffset = 0;
1284 DR.CVRegister = CVRegister;
1285 return DR;
1286}
1287
1288void CodeViewDebug::collectVariableInfoFromMFTable(
1289 DenseSet<InlinedEntity> &Processed) {
1290 const MachineFunction &MF = *Asm->MF;
1291 const TargetSubtargetInfo &TSI = MF.getSubtarget();
1292 const TargetFrameLowering *TFI = TSI.getFrameLowering();
1293 const TargetRegisterInfo *TRI = TSI.getRegisterInfo();
1294
1295 for (const MachineFunction::VariableDbgInfo &VI :
1296 MF.getInStackSlotVariableDbgInfo()) {
1297 if (!VI.Var)
1298 continue;
1299 assert(VI.Var->isValidLocationForIntrinsic(VI.Loc) &&
1300 "Expected inlined-at fields to agree");
1301
1302 Processed.insert(V: InlinedEntity(VI.Var, VI.Loc->getInlinedAt()));
1303 LexicalScope *Scope = LScopes.findLexicalScope(DL: VI.Loc);
1304
1305 // If variable scope is not found then skip this variable.
1306 if (!Scope)
1307 continue;
1308
1309 // If the variable has an attached offset expression, extract it.
1310 // FIXME: Try to handle DW_OP_deref as well.
1311 int64_t ExprOffset = 0;
1312 bool Deref = false;
1313 if (VI.Expr) {
1314 // If there is one DW_OP_deref element, use offset of 0 and keep going.
1315 if (VI.Expr->getNumElements() == 1 &&
1316 VI.Expr->getElement(I: 0) == llvm::dwarf::DW_OP_deref)
1317 Deref = true;
1318 else if (!VI.Expr->extractIfOffset(Offset&: ExprOffset))
1319 continue;
1320 }
1321
1322 // Get the frame register used and the offset.
1323 Register FrameReg;
1324 StackOffset FrameOffset =
1325 TFI->getFrameIndexReference(MF: *Asm->MF, FI: VI.getStackSlot(), FrameReg);
1326 uint16_t CVReg = TRI->getCodeViewRegNum(Reg: FrameReg);
1327
1328 if (FrameOffset.getScalable()) {
1329 // No encoding currently exists for scalable offsets; bail out.
1330 continue;
1331 }
1332
1333 // Calculate the label ranges.
1334 LocalVarDef DefRange =
1335 createDefRangeMem(CVRegister: CVReg, Offset: FrameOffset.getFixed() + ExprOffset);
1336
1337 LocalVariable Var;
1338 Var.DIVar = VI.Var;
1339
1340 for (const InsnRange &Range : Scope->getRanges()) {
1341 const MCSymbol *Begin = getLabelBeforeInsn(MI: Range.first);
1342 const MCSymbol *End = getLabelAfterInsn(MI: Range.second);
1343 End = End ? End : Asm->getFunctionEnd();
1344 Var.DefRanges[DefRange].emplace_back(Args&: Begin, Args&: End);
1345 }
1346
1347 if (Deref)
1348 Var.UseReferenceType = true;
1349
1350 recordLocalVariable(Var: std::move(Var), LS: Scope);
1351 }
1352}
1353
1354static bool canUseReferenceType(const DbgVariableLocation &Loc) {
1355 return !Loc.LoadChain.empty() && Loc.LoadChain.back() == 0;
1356}
1357
1358static bool needsReferenceType(const DbgVariableLocation &Loc) {
1359 return Loc.LoadChain.size() == 2 && Loc.LoadChain.back() == 0;
1360}
1361
1362void CodeViewDebug::calculateRanges(
1363 LocalVariable &Var, const DbgValueHistoryMap::Entries &Entries) {
1364 const TargetRegisterInfo *TRI = Asm->MF->getSubtarget().getRegisterInfo();
1365
1366 // Calculate the definition ranges.
1367 for (auto I = Entries.begin(), E = Entries.end(); I != E; ++I) {
1368 const auto &Entry = *I;
1369 if (!Entry.isDbgValue())
1370 continue;
1371 const MachineInstr *DVInst = Entry.getInstr();
1372 assert(DVInst->isDebugValue() && "Invalid History entry");
1373 // FIXME: Find a way to represent constant variables, since they are
1374 // relatively common.
1375 std::optional<DbgVariableLocation> Location =
1376 DbgVariableLocation::extractFromMachineInstruction(Instruction: *DVInst);
1377 if (!Location)
1378 {
1379 // When we don't have a location this is usually because LLVM has
1380 // transformed it into a constant and we only have an llvm.dbg.value. We
1381 // can't represent these well in CodeView since S_LOCAL only works on
1382 // registers and memory locations. Instead, we will pretend this to be a
1383 // constant value to at least have it show up in the debugger.
1384 auto Op = DVInst->getDebugOperand(Index: 0);
1385 if (Op.isImm())
1386 Var.ConstantValue = APSInt(APInt(64, Op.getImm()), false);
1387 continue;
1388 }
1389
1390 // CodeView can only express variables in register and variables in memory
1391 // at a constant offset from a register. However, for variables passed
1392 // indirectly by pointer, it is common for that pointer to be spilled to a
1393 // stack location. For the special case of one offseted load followed by a
1394 // zero offset load (a pointer spilled to the stack), we change the type of
1395 // the local variable from a value type to a reference type. This tricks the
1396 // debugger into doing the load for us.
1397 if (Var.UseReferenceType) {
1398 // We're using a reference type. Drop the last zero offset load.
1399 if (canUseReferenceType(Loc: *Location))
1400 Location->LoadChain.pop_back();
1401 else
1402 continue;
1403 } else if (needsReferenceType(Loc: *Location)) {
1404 // This location can't be expressed without switching to a reference type.
1405 // Start over using that.
1406 Var.UseReferenceType = true;
1407 Var.DefRanges.clear();
1408 calculateRanges(Var, Entries);
1409 return;
1410 }
1411
1412 // We can only handle a register or an offseted load of a register.
1413 if (!Location->Register || Location->LoadChain.size() > 1)
1414 continue;
1415
1416 // Codeview can only express byte-aligned offsets, ensure that we have a
1417 // byte-boundaried location.
1418 if (Location->FragmentInfo)
1419 if (Location->FragmentInfo->OffsetInBits % 8)
1420 continue;
1421
1422 if (TRI->isIgnoredCVReg(LLVMReg: Location->Register)) {
1423 // No encoding currently exists for this register; bail out.
1424 continue;
1425 }
1426
1427 LocalVarDef DR;
1428 DR.CVRegister = TRI->getCodeViewRegNum(Reg: Location->Register);
1429 DR.InMemory = !Location->LoadChain.empty();
1430 DR.DataOffset =
1431 !Location->LoadChain.empty() ? Location->LoadChain.back() : 0;
1432 if (Location->FragmentInfo) {
1433 DR.IsSubfield = true;
1434 DR.StructOffset = Location->FragmentInfo->OffsetInBits / 8;
1435 } else {
1436 DR.IsSubfield = false;
1437 DR.StructOffset = 0;
1438 }
1439
1440 // Compute the label range.
1441 const MCSymbol *Begin = getLabelBeforeInsn(MI: Entry.getInstr());
1442 const MCSymbol *End;
1443 if (Entry.getEndIndex() != DbgValueHistoryMap::NoEntry) {
1444 auto &EndingEntry = Entries[Entry.getEndIndex()];
1445 End = EndingEntry.isDbgValue()
1446 ? getLabelBeforeInsn(MI: EndingEntry.getInstr())
1447 : getLabelAfterInsn(MI: EndingEntry.getInstr());
1448 } else
1449 End = Asm->getFunctionEnd();
1450
1451 // If the last range end is our begin, just extend the last range.
1452 // Otherwise make a new range.
1453 SmallVectorImpl<std::pair<const MCSymbol *, const MCSymbol *>> &R =
1454 Var.DefRanges[DR];
1455 if (!R.empty() && R.back().second == Begin)
1456 R.back().second = End;
1457 else
1458 R.emplace_back(Args&: Begin, Args&: End);
1459
1460 // FIXME: Do more range combining.
1461 }
1462}
1463
1464void CodeViewDebug::collectVariableInfo(const DISubprogram *SP) {
1465 DenseSet<InlinedEntity> Processed;
1466 // Grab the variable info that was squirreled away in the MMI side-table.
1467 collectVariableInfoFromMFTable(Processed);
1468
1469 for (const auto &I : DbgValues) {
1470 InlinedEntity IV = I.first;
1471 if (Processed.count(V: IV))
1472 continue;
1473 const DILocalVariable *DIVar = cast<DILocalVariable>(Val: IV.first);
1474 const DILocation *InlinedAt = IV.second;
1475
1476 // Instruction ranges, specifying where IV is accessible.
1477 const auto &Entries = I.second;
1478
1479 LexicalScope *Scope = nullptr;
1480 if (InlinedAt)
1481 Scope = LScopes.findInlinedScope(N: DIVar->getScope(), IA: InlinedAt);
1482 else
1483 Scope = LScopes.findLexicalScope(N: DIVar->getScope());
1484 // If variable scope is not found then skip this variable.
1485 if (!Scope)
1486 continue;
1487
1488 LocalVariable Var;
1489 Var.DIVar = DIVar;
1490
1491 calculateRanges(Var, Entries);
1492 recordLocalVariable(Var: std::move(Var), LS: Scope);
1493 }
1494}
1495
1496void CodeViewDebug::beginFunctionImpl(const MachineFunction *MF) {
1497 const TargetSubtargetInfo &TSI = MF->getSubtarget();
1498 const TargetRegisterInfo *TRI = TSI.getRegisterInfo();
1499 const MachineFrameInfo &MFI = MF->getFrameInfo();
1500 const Function &GV = MF->getFunction();
1501 auto Insertion = FnDebugInfo.insert(KV: {&GV, std::make_unique<FunctionInfo>()});
1502 assert(Insertion.second && "function already has info");
1503 CurFn = Insertion.first->second.get();
1504 CurFn->FuncId = NextFuncId++;
1505 CurFn->Begin = Asm->getFunctionBegin();
1506
1507 // The S_FRAMEPROC record reports the stack size, and how many bytes of
1508 // callee-saved registers were used. For targets that don't use a PUSH
1509 // instruction (AArch64), this will be zero.
1510 CurFn->CSRSize = MFI.getCVBytesOfCalleeSavedRegisters();
1511 CurFn->FrameSize = MFI.getStackSize();
1512 CurFn->OffsetAdjustment = MFI.getOffsetAdjustment();
1513 CurFn->HasStackRealignment = TRI->hasStackRealignment(MF: *MF);
1514
1515 // For this function S_FRAMEPROC record, figure out which codeview register
1516 // will be the frame pointer.
1517 CurFn->EncodedParamFramePtrReg = EncodedFramePtrReg::None; // None.
1518 CurFn->EncodedLocalFramePtrReg = EncodedFramePtrReg::None; // None.
1519 if (CurFn->FrameSize > 0) {
1520 if (!TSI.getFrameLowering()->hasFP(MF: *MF)) {
1521 CurFn->EncodedLocalFramePtrReg = EncodedFramePtrReg::StackPtr;
1522 CurFn->EncodedParamFramePtrReg = EncodedFramePtrReg::StackPtr;
1523 } else {
1524 CurFn->HasFramePointer = true;
1525 // If there is an FP, parameters are always relative to it.
1526 CurFn->EncodedParamFramePtrReg = EncodedFramePtrReg::FramePtr;
1527 if (CurFn->HasStackRealignment) {
1528 // If the stack needs realignment, locals are relative to SP or VFRAME.
1529 CurFn->EncodedLocalFramePtrReg = EncodedFramePtrReg::StackPtr;
1530 } else {
1531 // Otherwise, locals are relative to EBP, and we probably have VLAs or
1532 // other stack adjustments.
1533 CurFn->EncodedLocalFramePtrReg = EncodedFramePtrReg::FramePtr;
1534 }
1535 }
1536 }
1537
1538 // Compute other frame procedure options.
1539 FrameProcedureOptions FPO = FrameProcedureOptions::None;
1540 if (MFI.hasVarSizedObjects())
1541 FPO |= FrameProcedureOptions::HasAlloca;
1542 if (MF->exposesReturnsTwice())
1543 FPO |= FrameProcedureOptions::HasSetJmp;
1544 // FIXME: Set HasLongJmp if we ever track that info.
1545 if (MF->hasInlineAsm())
1546 FPO |= FrameProcedureOptions::HasInlineAssembly;
1547 if (GV.hasPersonalityFn()) {
1548 if (isAsynchronousEHPersonality(
1549 Pers: classifyEHPersonality(Pers: GV.getPersonalityFn())))
1550 FPO |= FrameProcedureOptions::HasStructuredExceptionHandling;
1551 else
1552 FPO |= FrameProcedureOptions::HasExceptionHandling;
1553 }
1554 if (GV.hasFnAttribute(Kind: Attribute::InlineHint))
1555 FPO |= FrameProcedureOptions::MarkedInline;
1556 if (GV.hasFnAttribute(Kind: Attribute::Naked))
1557 FPO |= FrameProcedureOptions::Naked;
1558 if (MFI.hasStackProtectorIndex()) {
1559 FPO |= FrameProcedureOptions::SecurityChecks;
1560 if (GV.hasFnAttribute(Kind: Attribute::StackProtectStrong) ||
1561 GV.hasFnAttribute(Kind: Attribute::StackProtectReq)) {
1562 FPO |= FrameProcedureOptions::StrictSecurityChecks;
1563 }
1564 } else if (!GV.hasStackProtectorFnAttr()) {
1565 // __declspec(safebuffers) disables stack guards.
1566 FPO |= FrameProcedureOptions::SafeBuffers;
1567 }
1568 FPO |= FrameProcedureOptions(uint32_t(CurFn->EncodedLocalFramePtrReg) << 14U);
1569 FPO |= FrameProcedureOptions(uint32_t(CurFn->EncodedParamFramePtrReg) << 16U);
1570 if (Asm->TM.getOptLevel() != CodeGenOptLevel::None && !GV.hasOptSize() &&
1571 !GV.hasOptNone())
1572 FPO |= FrameProcedureOptions::OptimizedForSpeed;
1573 if (GV.hasProfileData()) {
1574 FPO |= FrameProcedureOptions::ValidProfileCounts;
1575 FPO |= FrameProcedureOptions::ProfileGuidedOptimization;
1576 }
1577 // FIXME: Set GuardCfg when it is implemented.
1578 CurFn->FrameProcOpts = FPO;
1579
1580 OS.emitCVFuncIdDirective(FunctionId: CurFn->FuncId);
1581
1582 // Find the end of the function prolog. First known non-DBG_VALUE and
1583 // non-frame setup location marks the beginning of the function body.
1584 // FIXME: is there a simpler a way to do this? Can we just search
1585 // for the first instruction of the function, not the last of the prolog?
1586 DebugLoc PrologEndLoc;
1587 bool EmptyPrologue = true;
1588 for (const auto &MBB : *MF) {
1589 for (const auto &MI : MBB) {
1590 if (!MI.isMetaInstruction() && !MI.getFlag(Flag: MachineInstr::FrameSetup) &&
1591 MI.getDebugLoc()) {
1592 PrologEndLoc = MI.getDebugLoc();
1593 break;
1594 } else if (!MI.isMetaInstruction()) {
1595 EmptyPrologue = false;
1596 }
1597 }
1598 }
1599
1600 // Record beginning of function if we have a non-empty prologue.
1601 if (PrologEndLoc && !EmptyPrologue) {
1602 DebugLoc FnStartDL = PrologEndLoc.getFnDebugLoc();
1603 maybeRecordLocation(DL: FnStartDL, MF);
1604 }
1605
1606 // Find heap alloc sites and emit labels around them.
1607 for (const auto &MBB : *MF) {
1608 for (const auto &MI : MBB) {
1609 if (MI.getHeapAllocMarker()) {
1610 requestLabelBeforeInsn(MI: &MI);
1611 requestLabelAfterInsn(MI: &MI);
1612 }
1613 }
1614 }
1615
1616 // Mark branches that may potentially be using jump tables with labels.
1617 bool isThumb = MMI->getModule()->getTargetTriple().getArch() ==
1618 llvm::Triple::ArchType::thumb;
1619 discoverJumpTableBranches(MF, isThumb);
1620}
1621
1622static bool shouldEmitUdt(const DIType *T) {
1623 if (!T)
1624 return false;
1625
1626 // MSVC does not emit UDTs for typedefs that are scoped to classes.
1627 if (T->getTag() == dwarf::DW_TAG_typedef) {
1628 if (DIScope *Scope = T->getScope()) {
1629 switch (Scope->getTag()) {
1630 case dwarf::DW_TAG_structure_type:
1631 case dwarf::DW_TAG_class_type:
1632 case dwarf::DW_TAG_union_type:
1633 return false;
1634 default:
1635 // do nothing.
1636 ;
1637 }
1638 }
1639 }
1640
1641 while (true) {
1642 if (!T || T->isForwardDecl())
1643 return false;
1644
1645 const DIDerivedType *DT = dyn_cast<DIDerivedType>(Val: T);
1646 if (!DT)
1647 return true;
1648 T = DT->getBaseType();
1649 }
1650 return true;
1651}
1652
1653void CodeViewDebug::addToUDTs(const DIType *Ty) {
1654 // Don't record empty UDTs.
1655 if (Ty->getName().empty())
1656 return;
1657 if (!shouldEmitUdt(T: Ty))
1658 return;
1659
1660 SmallVector<StringRef, 5> ParentScopeNames;
1661 const DISubprogram *ClosestSubprogram =
1662 collectParentScopeNames(Scope: Ty->getScope(), QualifiedNameComponents&: ParentScopeNames);
1663
1664 std::string FullyQualifiedName =
1665 formatNestedName(QualifiedNameComponents: ParentScopeNames, TypeName: getPrettyScopeName(Scope: Ty));
1666
1667 if (ClosestSubprogram == nullptr) {
1668 GlobalUDTs.emplace_back(args: std::move(FullyQualifiedName), args&: Ty);
1669 } else if (ClosestSubprogram == CurrentSubprogram) {
1670 LocalUDTs.emplace_back(args: std::move(FullyQualifiedName), args&: Ty);
1671 }
1672
1673 // TODO: What if the ClosestSubprogram is neither null or the current
1674 // subprogram? Currently, the UDT just gets dropped on the floor.
1675 //
1676 // The current behavior is not desirable. To get maximal fidelity, we would
1677 // need to perform all type translation before beginning emission of .debug$S
1678 // and then make LocalUDTs a member of FunctionInfo
1679}
1680
1681TypeIndex CodeViewDebug::lowerType(const DIType *Ty, const DIType *ClassTy) {
1682 // Generic dispatch for lowering an unknown type.
1683 switch (Ty->getTag()) {
1684 case dwarf::DW_TAG_array_type:
1685 return lowerTypeArray(Ty: cast<DICompositeType>(Val: Ty));
1686 case dwarf::DW_TAG_typedef:
1687 return lowerTypeAlias(Ty: cast<DIDerivedType>(Val: Ty));
1688 case dwarf::DW_TAG_base_type:
1689 return lowerTypeBasic(Ty: cast<DIBasicType>(Val: Ty));
1690 case dwarf::DW_TAG_pointer_type:
1691 if (cast<DIDerivedType>(Val: Ty)->getName() == "__vtbl_ptr_type")
1692 return lowerTypeVFTableShape(Ty: cast<DIDerivedType>(Val: Ty));
1693 [[fallthrough]];
1694 case dwarf::DW_TAG_reference_type:
1695 case dwarf::DW_TAG_rvalue_reference_type:
1696 return lowerTypePointer(Ty: cast<DIDerivedType>(Val: Ty));
1697 case dwarf::DW_TAG_ptr_to_member_type:
1698 return lowerTypeMemberPointer(Ty: cast<DIDerivedType>(Val: Ty));
1699 case dwarf::DW_TAG_restrict_type:
1700 case dwarf::DW_TAG_const_type:
1701 case dwarf::DW_TAG_volatile_type:
1702 // TODO: add support for DW_TAG_atomic_type here
1703 return lowerTypeModifier(Ty: cast<DIDerivedType>(Val: Ty));
1704 case dwarf::DW_TAG_subroutine_type:
1705 if (ClassTy) {
1706 // The member function type of a member function pointer has no
1707 // ThisAdjustment.
1708 return lowerTypeMemberFunction(Ty: cast<DISubroutineType>(Val: Ty), ClassTy,
1709 /*ThisAdjustment=*/0,
1710 /*IsStaticMethod=*/false);
1711 }
1712 return lowerTypeFunction(Ty: cast<DISubroutineType>(Val: Ty));
1713 case dwarf::DW_TAG_enumeration_type:
1714 return lowerTypeEnum(Ty: cast<DICompositeType>(Val: Ty));
1715 case dwarf::DW_TAG_class_type:
1716 case dwarf::DW_TAG_structure_type:
1717 return lowerTypeClass(Ty: cast<DICompositeType>(Val: Ty));
1718 case dwarf::DW_TAG_union_type:
1719 return lowerTypeUnion(Ty: cast<DICompositeType>(Val: Ty));
1720 case dwarf::DW_TAG_string_type:
1721 return lowerTypeString(Ty: cast<DIStringType>(Val: Ty));
1722 case dwarf::DW_TAG_unspecified_type:
1723 if (Ty->getName() == "decltype(nullptr)")
1724 return TypeIndex::NullptrT();
1725 return TypeIndex::None();
1726 default:
1727 // Use the null type index.
1728 return TypeIndex();
1729 }
1730}
1731
1732TypeIndex CodeViewDebug::lowerTypeAlias(const DIDerivedType *Ty) {
1733 TypeIndex UnderlyingTypeIndex = getTypeIndex(Ty: Ty->getBaseType());
1734 StringRef TypeName = Ty->getName();
1735
1736 addToUDTs(Ty);
1737
1738 if (UnderlyingTypeIndex == TypeIndex(SimpleTypeKind::Int32Long) &&
1739 TypeName == "HRESULT")
1740 return TypeIndex(SimpleTypeKind::HResult);
1741 if (UnderlyingTypeIndex == TypeIndex(SimpleTypeKind::UInt16Short) &&
1742 TypeName == "wchar_t")
1743 return TypeIndex(SimpleTypeKind::WideCharacter);
1744
1745 return UnderlyingTypeIndex;
1746}
1747
1748TypeIndex CodeViewDebug::lowerTypeArray(const DICompositeType *Ty) {
1749 const DIType *ElementType = Ty->getBaseType();
1750 TypeIndex ElementTypeIndex = getTypeIndex(Ty: ElementType);
1751 // IndexType is size_t, which depends on the bitness of the target.
1752 TypeIndex IndexType = getPointerSizeInBytes() == 8
1753 ? TypeIndex(SimpleTypeKind::UInt64Quad)
1754 : TypeIndex(SimpleTypeKind::UInt32Long);
1755
1756 uint64_t ElementSize = getBaseTypeSize(Ty: ElementType) / 8;
1757
1758 // Add subranges to array type.
1759 DINodeArray Elements = Ty->getElements();
1760 for (int i = Elements.size() - 1; i >= 0; --i) {
1761 const DINode *Element = Elements[i];
1762 assert(Element->getTag() == dwarf::DW_TAG_subrange_type);
1763
1764 const DISubrange *Subrange = cast<DISubrange>(Val: Element);
1765 int64_t Count = -1;
1766
1767 // If Subrange has a Count field, use it.
1768 // Otherwise, if it has an upperboud, use (upperbound - lowerbound + 1),
1769 // where lowerbound is from the LowerBound field of the Subrange,
1770 // or the language default lowerbound if that field is unspecified.
1771 if (auto *CI = dyn_cast_if_present<ConstantInt *>(Val: Subrange->getCount()))
1772 Count = CI->getSExtValue();
1773 else if (auto *UI = dyn_cast_if_present<ConstantInt *>(
1774 Val: Subrange->getUpperBound())) {
1775 // Fortran uses 1 as the default lowerbound; other languages use 0.
1776 int64_t Lowerbound = (moduleIsInFortran()) ? 1 : 0;
1777 auto *LI = dyn_cast_if_present<ConstantInt *>(Val: Subrange->getLowerBound());
1778 Lowerbound = (LI) ? LI->getSExtValue() : Lowerbound;
1779 Count = UI->getSExtValue() - Lowerbound + 1;
1780 }
1781
1782 // Forward declarations of arrays without a size and VLAs use a count of -1.
1783 // Emit a count of zero in these cases to match what MSVC does for arrays
1784 // without a size. MSVC doesn't support VLAs, so it's not clear what we
1785 // should do for them even if we could distinguish them.
1786 if (Count == -1)
1787 Count = 0;
1788
1789 // Update the element size and element type index for subsequent subranges.
1790 ElementSize *= Count;
1791
1792 // If this is the outermost array, use the size from the array. It will be
1793 // more accurate if we had a VLA or an incomplete element type size.
1794 uint64_t ArraySize =
1795 (i == 0 && ElementSize == 0) ? Ty->getSizeInBits() / 8 : ElementSize;
1796
1797 StringRef Name = (i == 0) ? Ty->getName() : "";
1798 ArrayRecord AR(ElementTypeIndex, IndexType, ArraySize, Name);
1799 ElementTypeIndex = TypeTable.writeLeafType(Record&: AR);
1800 }
1801
1802 return ElementTypeIndex;
1803}
1804
1805// This function lowers a Fortran character type (DIStringType).
1806// Note that it handles only the character*n variant (using SizeInBits
1807// field in DIString to describe the type size) at the moment.
1808// Other variants (leveraging the StringLength and StringLengthExp
1809// fields in DIStringType) remain TBD.
1810TypeIndex CodeViewDebug::lowerTypeString(const DIStringType *Ty) {
1811 TypeIndex CharType = TypeIndex(SimpleTypeKind::NarrowCharacter);
1812 uint64_t ArraySize = Ty->getSizeInBits() >> 3;
1813 StringRef Name = Ty->getName();
1814 // IndexType is size_t, which depends on the bitness of the target.
1815 TypeIndex IndexType = getPointerSizeInBytes() == 8
1816 ? TypeIndex(SimpleTypeKind::UInt64Quad)
1817 : TypeIndex(SimpleTypeKind::UInt32Long);
1818
1819 // Create a type of character array of ArraySize.
1820 ArrayRecord AR(CharType, IndexType, ArraySize, Name);
1821
1822 return TypeTable.writeLeafType(Record&: AR);
1823}
1824
1825TypeIndex CodeViewDebug::lowerTypeBasic(const DIBasicType *Ty) {
1826 TypeIndex Index;
1827 dwarf::TypeKind Kind;
1828 uint32_t ByteSize;
1829
1830 Kind = static_cast<dwarf::TypeKind>(Ty->getEncoding());
1831 ByteSize = Ty->getSizeInBits() / 8;
1832
1833 SimpleTypeKind STK = SimpleTypeKind::None;
1834 switch (Kind) {
1835 case dwarf::DW_ATE_address:
1836 // FIXME: Translate
1837 break;
1838 case dwarf::DW_ATE_boolean:
1839 switch (ByteSize) {
1840 case 1: STK = SimpleTypeKind::Boolean8; break;
1841 case 2: STK = SimpleTypeKind::Boolean16; break;
1842 case 4: STK = SimpleTypeKind::Boolean32; break;
1843 case 8: STK = SimpleTypeKind::Boolean64; break;
1844 case 16: STK = SimpleTypeKind::Boolean128; break;
1845 }
1846 break;
1847 case dwarf::DW_ATE_complex_float:
1848 // The CodeView size for a complex represents the size of
1849 // an individual component.
1850 switch (ByteSize) {
1851 case 4: STK = SimpleTypeKind::Complex16; break;
1852 case 8: STK = SimpleTypeKind::Complex32; break;
1853 case 16: STK = SimpleTypeKind::Complex64; break;
1854 case 20: STK = SimpleTypeKind::Complex80; break;
1855 case 32: STK = SimpleTypeKind::Complex128; break;
1856 }
1857 break;
1858 case dwarf::DW_ATE_float:
1859 switch (ByteSize) {
1860 case 2: STK = SimpleTypeKind::Float16; break;
1861 case 4: STK = SimpleTypeKind::Float32; break;
1862 case 6: STK = SimpleTypeKind::Float48; break;
1863 case 8: STK = SimpleTypeKind::Float64; break;
1864 case 10: STK = SimpleTypeKind::Float80; break;
1865 case 16: STK = SimpleTypeKind::Float128; break;
1866 }
1867 break;
1868 case dwarf::DW_ATE_signed:
1869 switch (ByteSize) {
1870 case 1: STK = SimpleTypeKind::SignedCharacter; break;
1871 case 2: STK = SimpleTypeKind::Int16Short; break;
1872 case 4: STK = SimpleTypeKind::Int32; break;
1873 case 8: STK = SimpleTypeKind::Int64Quad; break;
1874 case 16: STK = SimpleTypeKind::Int128Oct; break;
1875 }
1876 break;
1877 case dwarf::DW_ATE_unsigned:
1878 switch (ByteSize) {
1879 case 1: STK = SimpleTypeKind::UnsignedCharacter; break;
1880 case 2: STK = SimpleTypeKind::UInt16Short; break;
1881 case 4: STK = SimpleTypeKind::UInt32; break;
1882 case 8: STK = SimpleTypeKind::UInt64Quad; break;
1883 case 16: STK = SimpleTypeKind::UInt128Oct; break;
1884 }
1885 break;
1886 case dwarf::DW_ATE_UTF:
1887 switch (ByteSize) {
1888 case 1: STK = SimpleTypeKind::Character8; break;
1889 case 2: STK = SimpleTypeKind::Character16; break;
1890 case 4: STK = SimpleTypeKind::Character32; break;
1891 }
1892 break;
1893 case dwarf::DW_ATE_signed_char:
1894 if (ByteSize == 1)
1895 STK = SimpleTypeKind::SignedCharacter;
1896 break;
1897 case dwarf::DW_ATE_unsigned_char:
1898 if (ByteSize == 1)
1899 STK = SimpleTypeKind::UnsignedCharacter;
1900 break;
1901 default:
1902 break;
1903 }
1904
1905 // Apply some fixups based on the source-level type name.
1906 // Include some amount of canonicalization from an old naming scheme Clang
1907 // used to use for integer types (in an outdated effort to be compatible with
1908 // GCC's debug info/GDB's behavior, which has since been addressed).
1909 if (STK == SimpleTypeKind::Int32 &&
1910 (Ty->getName() == "long int" || Ty->getName() == "long"))
1911 STK = SimpleTypeKind::Int32Long;
1912 if (STK == SimpleTypeKind::UInt32 && (Ty->getName() == "long unsigned int" ||
1913 Ty->getName() == "unsigned long"))
1914 STK = SimpleTypeKind::UInt32Long;
1915 if (STK == SimpleTypeKind::UInt16Short &&
1916 (Ty->getName() == "wchar_t" || Ty->getName() == "__wchar_t"))
1917 STK = SimpleTypeKind::WideCharacter;
1918 if ((STK == SimpleTypeKind::SignedCharacter ||
1919 STK == SimpleTypeKind::UnsignedCharacter) &&
1920 Ty->getName() == "char")
1921 STK = SimpleTypeKind::NarrowCharacter;
1922
1923 return TypeIndex(STK);
1924}
1925
1926TypeIndex CodeViewDebug::lowerTypePointer(const DIDerivedType *Ty,
1927 PointerOptions PO) {
1928 TypeIndex PointeeTI = getTypeIndex(Ty: Ty->getBaseType());
1929
1930 // Pointers to simple types without any options can use SimpleTypeMode, rather
1931 // than having a dedicated pointer type record.
1932 if (PointeeTI.isSimple() && PO == PointerOptions::None &&
1933 PointeeTI.getSimpleMode() == SimpleTypeMode::Direct &&
1934 Ty->getTag() == dwarf::DW_TAG_pointer_type) {
1935 SimpleTypeMode Mode = Ty->getSizeInBits() == 64
1936 ? SimpleTypeMode::NearPointer64
1937 : SimpleTypeMode::NearPointer32;
1938 return TypeIndex(PointeeTI.getSimpleKind(), Mode);
1939 }
1940
1941 PointerKind PK =
1942 Ty->getSizeInBits() == 64 ? PointerKind::Near64 : PointerKind::Near32;
1943 PointerMode PM = PointerMode::Pointer;
1944 switch (Ty->getTag()) {
1945 default: llvm_unreachable("not a pointer tag type");
1946 case dwarf::DW_TAG_pointer_type:
1947 PM = PointerMode::Pointer;
1948 break;
1949 case dwarf::DW_TAG_reference_type:
1950 PM = PointerMode::LValueReference;
1951 break;
1952 case dwarf::DW_TAG_rvalue_reference_type:
1953 PM = PointerMode::RValueReference;
1954 break;
1955 }
1956
1957 if (Ty->isObjectPointer())
1958 PO |= PointerOptions::Const;
1959
1960 PointerRecord PR(PointeeTI, PK, PM, PO, Ty->getSizeInBits() / 8);
1961 return TypeTable.writeLeafType(Record&: PR);
1962}
1963
1964static PointerToMemberRepresentation
1965translatePtrToMemberRep(unsigned SizeInBytes, bool IsPMF, unsigned Flags) {
1966 // SizeInBytes being zero generally implies that the member pointer type was
1967 // incomplete, which can happen if it is part of a function prototype. In this
1968 // case, use the unknown model instead of the general model.
1969 if (IsPMF) {
1970 switch (Flags & DINode::FlagPtrToMemberRep) {
1971 case 0:
1972 return SizeInBytes == 0 ? PointerToMemberRepresentation::Unknown
1973 : PointerToMemberRepresentation::GeneralFunction;
1974 case DINode::FlagSingleInheritance:
1975 return PointerToMemberRepresentation::SingleInheritanceFunction;
1976 case DINode::FlagMultipleInheritance:
1977 return PointerToMemberRepresentation::MultipleInheritanceFunction;
1978 case DINode::FlagVirtualInheritance:
1979 return PointerToMemberRepresentation::VirtualInheritanceFunction;
1980 }
1981 } else {
1982 switch (Flags & DINode::FlagPtrToMemberRep) {
1983 case 0:
1984 return SizeInBytes == 0 ? PointerToMemberRepresentation::Unknown
1985 : PointerToMemberRepresentation::GeneralData;
1986 case DINode::FlagSingleInheritance:
1987 return PointerToMemberRepresentation::SingleInheritanceData;
1988 case DINode::FlagMultipleInheritance:
1989 return PointerToMemberRepresentation::MultipleInheritanceData;
1990 case DINode::FlagVirtualInheritance:
1991 return PointerToMemberRepresentation::VirtualInheritanceData;
1992 }
1993 }
1994 llvm_unreachable("invalid ptr to member representation");
1995}
1996
1997TypeIndex CodeViewDebug::lowerTypeMemberPointer(const DIDerivedType *Ty,
1998 PointerOptions PO) {
1999 assert(Ty->getTag() == dwarf::DW_TAG_ptr_to_member_type);
2000 bool IsPMF = isa<DISubroutineType>(Val: Ty->getBaseType());
2001 TypeIndex ClassTI = getTypeIndex(Ty: Ty->getClassType());
2002 TypeIndex PointeeTI =
2003 getTypeIndex(Ty: Ty->getBaseType(), ClassTy: IsPMF ? Ty->getClassType() : nullptr);
2004 PointerKind PK = getPointerSizeInBytes() == 8 ? PointerKind::Near64
2005 : PointerKind::Near32;
2006 PointerMode PM = IsPMF ? PointerMode::PointerToMemberFunction
2007 : PointerMode::PointerToDataMember;
2008
2009 assert(Ty->getSizeInBits() / 8 <= 0xff && "pointer size too big");
2010 uint8_t SizeInBytes = Ty->getSizeInBits() / 8;
2011 MemberPointerInfo MPI(
2012 ClassTI, translatePtrToMemberRep(SizeInBytes, IsPMF, Flags: Ty->getFlags()));
2013 PointerRecord PR(PointeeTI, PK, PM, PO, SizeInBytes, MPI);
2014 return TypeTable.writeLeafType(Record&: PR);
2015}
2016
2017/// Given a DWARF calling convention, get the CodeView equivalent. If we don't
2018/// have a translation, use the NearC convention.
2019static CallingConvention dwarfCCToCodeView(unsigned DwarfCC) {
2020 switch (DwarfCC) {
2021 case dwarf::DW_CC_normal: return CallingConvention::NearC;
2022 case dwarf::DW_CC_BORLAND_msfastcall: return CallingConvention::NearFast;
2023 case dwarf::DW_CC_BORLAND_thiscall: return CallingConvention::ThisCall;
2024 case dwarf::DW_CC_BORLAND_stdcall: return CallingConvention::NearStdCall;
2025 case dwarf::DW_CC_BORLAND_pascal: return CallingConvention::NearPascal;
2026 case dwarf::DW_CC_LLVM_vectorcall: return CallingConvention::NearVector;
2027 }
2028 return CallingConvention::NearC;
2029}
2030
2031TypeIndex CodeViewDebug::lowerTypeModifier(const DIDerivedType *Ty) {
2032 ModifierOptions Mods = ModifierOptions::None;
2033 PointerOptions PO = PointerOptions::None;
2034 bool IsModifier = true;
2035 const DIType *BaseTy = Ty;
2036 while (IsModifier && BaseTy) {
2037 // FIXME: Need to add DWARF tags for __unaligned and _Atomic
2038 switch (BaseTy->getTag()) {
2039 case dwarf::DW_TAG_const_type:
2040 Mods |= ModifierOptions::Const;
2041 PO |= PointerOptions::Const;
2042 break;
2043 case dwarf::DW_TAG_volatile_type:
2044 Mods |= ModifierOptions::Volatile;
2045 PO |= PointerOptions::Volatile;
2046 break;
2047 case dwarf::DW_TAG_restrict_type:
2048 // Only pointer types be marked with __restrict. There is no known flag
2049 // for __restrict in LF_MODIFIER records.
2050 PO |= PointerOptions::Restrict;
2051 break;
2052 default:
2053 IsModifier = false;
2054 break;
2055 }
2056 if (IsModifier)
2057 BaseTy = cast<DIDerivedType>(Val: BaseTy)->getBaseType();
2058 }
2059
2060 // Check if the inner type will use an LF_POINTER record. If so, the
2061 // qualifiers will go in the LF_POINTER record. This comes up for types like
2062 // 'int *const' and 'int *__restrict', not the more common cases like 'const
2063 // char *'.
2064 if (BaseTy) {
2065 switch (BaseTy->getTag()) {
2066 case dwarf::DW_TAG_pointer_type:
2067 case dwarf::DW_TAG_reference_type:
2068 case dwarf::DW_TAG_rvalue_reference_type:
2069 return lowerTypePointer(Ty: cast<DIDerivedType>(Val: BaseTy), PO);
2070 case dwarf::DW_TAG_ptr_to_member_type:
2071 return lowerTypeMemberPointer(Ty: cast<DIDerivedType>(Val: BaseTy), PO);
2072 default:
2073 break;
2074 }
2075 }
2076
2077 TypeIndex ModifiedTI = getTypeIndex(Ty: BaseTy);
2078
2079 // Return the base type index if there aren't any modifiers. For example, the
2080 // metadata could contain restrict wrappers around non-pointer types.
2081 if (Mods == ModifierOptions::None)
2082 return ModifiedTI;
2083
2084 ModifierRecord MR(ModifiedTI, Mods);
2085 return TypeTable.writeLeafType(Record&: MR);
2086}
2087
2088TypeIndex CodeViewDebug::lowerTypeFunction(const DISubroutineType *Ty) {
2089 SmallVector<TypeIndex, 8> ReturnAndArgTypeIndices;
2090 for (const DIType *ArgType : Ty->getTypeArray())
2091 ReturnAndArgTypeIndices.push_back(Elt: getTypeIndex(Ty: ArgType));
2092
2093 // MSVC uses type none for variadic argument.
2094 if (ReturnAndArgTypeIndices.size() > 1 &&
2095 ReturnAndArgTypeIndices.back() == TypeIndex::Void()) {
2096 ReturnAndArgTypeIndices.back() = TypeIndex::None();
2097 }
2098 TypeIndex ReturnTypeIndex = TypeIndex::Void();
2099 ArrayRef<TypeIndex> ArgTypeIndices = {};
2100 if (!ReturnAndArgTypeIndices.empty()) {
2101 auto ReturnAndArgTypesRef = ArrayRef(ReturnAndArgTypeIndices);
2102 ReturnTypeIndex = ReturnAndArgTypesRef.consume_front();
2103 ArgTypeIndices = ReturnAndArgTypesRef;
2104 }
2105
2106 ArgListRecord ArgListRec(TypeRecordKind::ArgList, ArgTypeIndices);
2107 TypeIndex ArgListIndex = TypeTable.writeLeafType(Record&: ArgListRec);
2108
2109 CallingConvention CC = dwarfCCToCodeView(DwarfCC: Ty->getCC());
2110
2111 FunctionOptions FO = getFunctionOptions(Ty);
2112 ProcedureRecord Procedure(ReturnTypeIndex, CC, FO, ArgTypeIndices.size(),
2113 ArgListIndex);
2114 return TypeTable.writeLeafType(Record&: Procedure);
2115}
2116
2117TypeIndex CodeViewDebug::lowerTypeMemberFunction(const DISubroutineType *Ty,
2118 const DIType *ClassTy,
2119 int ThisAdjustment,
2120 bool IsStaticMethod,
2121 FunctionOptions FO) {
2122 // Lower the containing class type.
2123 TypeIndex ClassType = getTypeIndex(Ty: ClassTy);
2124
2125 DITypeArray ReturnAndArgs = Ty->getTypeArray();
2126
2127 unsigned Index = 0;
2128 SmallVector<TypeIndex, 8> ArgTypeIndices;
2129 TypeIndex ReturnTypeIndex = TypeIndex::Void();
2130 if (ReturnAndArgs.size() > Index) {
2131 ReturnTypeIndex = getTypeIndex(Ty: ReturnAndArgs[Index++]);
2132 }
2133
2134 // If the first argument is a pointer type and this isn't a static method,
2135 // treat it as the special 'this' parameter, which is encoded separately from
2136 // the arguments.
2137 TypeIndex ThisTypeIndex;
2138 if (!IsStaticMethod && ReturnAndArgs.size() > Index) {
2139 if (const DIDerivedType *PtrTy =
2140 dyn_cast_or_null<DIDerivedType>(Val: ReturnAndArgs[Index])) {
2141 if (PtrTy->getTag() == dwarf::DW_TAG_pointer_type) {
2142 ThisTypeIndex = getTypeIndexForThisPtr(PtrTy, SubroutineTy: Ty);
2143 Index++;
2144 }
2145 }
2146 }
2147
2148 while (Index < ReturnAndArgs.size())
2149 ArgTypeIndices.push_back(Elt: getTypeIndex(Ty: ReturnAndArgs[Index++]));
2150
2151 // MSVC uses type none for variadic argument.
2152 if (!ArgTypeIndices.empty() && ArgTypeIndices.back() == TypeIndex::Void())
2153 ArgTypeIndices.back() = TypeIndex::None();
2154
2155 ArgListRecord ArgListRec(TypeRecordKind::ArgList, ArgTypeIndices);
2156 TypeIndex ArgListIndex = TypeTable.writeLeafType(Record&: ArgListRec);
2157
2158 CallingConvention CC = dwarfCCToCodeView(DwarfCC: Ty->getCC());
2159
2160 MemberFunctionRecord MFR(ReturnTypeIndex, ClassType, ThisTypeIndex, CC, FO,
2161 ArgTypeIndices.size(), ArgListIndex, ThisAdjustment);
2162 return TypeTable.writeLeafType(Record&: MFR);
2163}
2164
2165TypeIndex CodeViewDebug::lowerTypeVFTableShape(const DIDerivedType *Ty) {
2166 unsigned VSlotCount =
2167 Ty->getSizeInBits() / (8 * Asm->MAI->getCodePointerSize());
2168 SmallVector<VFTableSlotKind, 4> Slots(VSlotCount, VFTableSlotKind::Near);
2169
2170 VFTableShapeRecord VFTSR(Slots);
2171 return TypeTable.writeLeafType(Record&: VFTSR);
2172}
2173
2174static MemberAccess translateAccessFlags(unsigned RecordTag, unsigned Flags) {
2175 switch (Flags & DINode::FlagAccessibility) {
2176 case DINode::FlagPrivate: return MemberAccess::Private;
2177 case DINode::FlagPublic: return MemberAccess::Public;
2178 case DINode::FlagProtected: return MemberAccess::Protected;
2179 case 0:
2180 // If there was no explicit access control, provide the default for the tag.
2181 return RecordTag == dwarf::DW_TAG_class_type ? MemberAccess::Private
2182 : MemberAccess::Public;
2183 }
2184 llvm_unreachable("access flags are exclusive");
2185}
2186
2187static MethodOptions translateMethodOptionFlags(const DISubprogram *SP) {
2188 if (SP->isArtificial())
2189 return MethodOptions::CompilerGenerated;
2190
2191 // FIXME: Handle other MethodOptions.
2192
2193 return MethodOptions::None;
2194}
2195
2196static MethodKind translateMethodKindFlags(const DISubprogram *SP,
2197 bool Introduced) {
2198 if (SP->getFlags() & DINode::FlagStaticMember)
2199 return MethodKind::Static;
2200
2201 switch (SP->getVirtuality()) {
2202 case dwarf::DW_VIRTUALITY_none:
2203 break;
2204 case dwarf::DW_VIRTUALITY_virtual:
2205 return Introduced ? MethodKind::IntroducingVirtual : MethodKind::Virtual;
2206 case dwarf::DW_VIRTUALITY_pure_virtual:
2207 return Introduced ? MethodKind::PureIntroducingVirtual
2208 : MethodKind::PureVirtual;
2209 default:
2210 llvm_unreachable("unhandled virtuality case");
2211 }
2212
2213 return MethodKind::Vanilla;
2214}
2215
2216static TypeRecordKind getRecordKind(const DICompositeType *Ty) {
2217 switch (Ty->getTag()) {
2218 case dwarf::DW_TAG_class_type:
2219 return TypeRecordKind::Class;
2220 case dwarf::DW_TAG_structure_type:
2221 return TypeRecordKind::Struct;
2222 default:
2223 llvm_unreachable("unexpected tag");
2224 }
2225}
2226
2227/// Return ClassOptions that should be present on both the forward declaration
2228/// and the defintion of a tag type.
2229static ClassOptions getCommonClassOptions(const DICompositeType *Ty) {
2230 ClassOptions CO = ClassOptions::None;
2231
2232 // MSVC always sets this flag, even for local types. Clang doesn't always
2233 // appear to give every type a linkage name, which may be problematic for us.
2234 // FIXME: Investigate the consequences of not following them here.
2235 if (!Ty->getIdentifier().empty())
2236 CO |= ClassOptions::HasUniqueName;
2237
2238 // Put the Nested flag on a type if it appears immediately inside a tag type.
2239 // Do not walk the scope chain. Do not attempt to compute ContainsNestedClass
2240 // here. That flag is only set on definitions, and not forward declarations.
2241 const DIScope *ImmediateScope = Ty->getScope();
2242 if (ImmediateScope && isa<DICompositeType>(Val: ImmediateScope))
2243 CO |= ClassOptions::Nested;
2244
2245 // Put the Scoped flag on function-local types. MSVC puts this flag for enum
2246 // type only when it has an immediate function scope. Clang never puts enums
2247 // inside DILexicalBlock scopes. Enum types, as generated by clang, are
2248 // always in function, class, or file scopes.
2249 if (Ty->getTag() == dwarf::DW_TAG_enumeration_type) {
2250 if (ImmediateScope && isa<DISubprogram>(Val: ImmediateScope))
2251 CO |= ClassOptions::Scoped;
2252 } else {
2253 for (const DIScope *Scope = ImmediateScope; Scope != nullptr;
2254 Scope = Scope->getScope()) {
2255 if (isa<DISubprogram>(Val: Scope)) {
2256 CO |= ClassOptions::Scoped;
2257 break;
2258 }
2259 }
2260 }
2261
2262 return CO;
2263}
2264
2265void CodeViewDebug::addUDTSrcLine(const DIType *Ty, TypeIndex TI) {
2266 switch (Ty->getTag()) {
2267 case dwarf::DW_TAG_class_type:
2268 case dwarf::DW_TAG_structure_type:
2269 case dwarf::DW_TAG_union_type:
2270 case dwarf::DW_TAG_enumeration_type:
2271 break;
2272 default:
2273 return;
2274 }
2275
2276 if (const auto *File = Ty->getFile()) {
2277 StringIdRecord SIDR(TypeIndex(0x0), getFullFilepath(File));
2278 TypeIndex SIDI = TypeTable.writeLeafType(Record&: SIDR);
2279
2280 UdtSourceLineRecord USLR(TI, SIDI, Ty->getLine());
2281 TypeTable.writeLeafType(Record&: USLR);
2282 }
2283}
2284
2285TypeIndex CodeViewDebug::lowerTypeEnum(const DICompositeType *Ty) {
2286 ClassOptions CO = getCommonClassOptions(Ty);
2287 TypeIndex FTI;
2288 unsigned EnumeratorCount = 0;
2289
2290 if (Ty->isForwardDecl()) {
2291 CO |= ClassOptions::ForwardReference;
2292 } else {
2293 ContinuationRecordBuilder ContinuationBuilder;
2294 ContinuationBuilder.begin(RecordKind: ContinuationRecordKind::FieldList);
2295 for (const DINode *Element : Ty->getElements()) {
2296 // We assume that the frontend provides all members in source declaration
2297 // order, which is what MSVC does.
2298 if (auto *Enumerator = dyn_cast_or_null<DIEnumerator>(Val: Element)) {
2299 // FIXME: Is it correct to always emit these as unsigned here?
2300 EnumeratorRecord ER(MemberAccess::Public,
2301 APSInt(Enumerator->getValue(), true),
2302 Enumerator->getName());
2303 ContinuationBuilder.writeMemberType(Record&: ER);
2304 EnumeratorCount++;
2305 }
2306 }
2307 FTI = TypeTable.insertRecord(Builder&: ContinuationBuilder);
2308 }
2309
2310 std::string FullName = getFullyQualifiedName(Ty);
2311
2312 EnumRecord ER(EnumeratorCount, CO, FTI, FullName, Ty->getIdentifier(),
2313 getTypeIndex(Ty: Ty->getBaseType()));
2314 TypeIndex EnumTI = TypeTable.writeLeafType(Record&: ER);
2315
2316 addUDTSrcLine(Ty, TI: EnumTI);
2317
2318 return EnumTI;
2319}
2320
2321//===----------------------------------------------------------------------===//
2322// ClassInfo
2323//===----------------------------------------------------------------------===//
2324
2325struct llvm::ClassInfo {
2326 struct MemberInfo {
2327 const DIDerivedType *MemberTypeNode;
2328 uint64_t BaseOffset;
2329 };
2330 // [MemberInfo]
2331 using MemberList = std::vector<MemberInfo>;
2332
2333 using MethodsList = TinyPtrVector<const DISubprogram *>;
2334 // MethodName -> MethodsList
2335 using MethodsMap = MapVector<MDString *, MethodsList>;
2336
2337 /// Base classes.
2338 std::vector<const DIDerivedType *> Inheritance;
2339
2340 /// Direct members.
2341 MemberList Members;
2342 // Direct overloaded methods gathered by name.
2343 MethodsMap Methods;
2344
2345 TypeIndex VShapeTI;
2346
2347 std::vector<const DIType *> NestedTypes;
2348};
2349
2350void CodeViewDebug::clear() {
2351 assert(CurFn == nullptr);
2352 FileIdMap.clear();
2353 FnDebugInfo.clear();
2354 FileToFilepathMap.clear();
2355 LocalUDTs.clear();
2356 GlobalUDTs.clear();
2357 TypeIndices.clear();
2358 CompleteTypeIndices.clear();
2359 ScopeGlobals.clear();
2360 CVGlobalVariableOffsets.clear();
2361}
2362
2363void CodeViewDebug::collectMemberInfo(ClassInfo &Info,
2364 const DIDerivedType *DDTy) {
2365 if (!DDTy->getName().empty()) {
2366 Info.Members.push_back(x: {.MemberTypeNode: DDTy, .BaseOffset: 0});
2367
2368 // Collect static const data members with values.
2369 if ((DDTy->getFlags() & DINode::FlagStaticMember) ==
2370 DINode::FlagStaticMember) {
2371 if (DDTy->getConstant() && (isa<ConstantInt>(Val: DDTy->getConstant()) ||
2372 isa<ConstantFP>(Val: DDTy->getConstant())))
2373 StaticConstMembers.push_back(Elt: DDTy);
2374 }
2375
2376 return;
2377 }
2378
2379 // An unnamed member may represent a nested struct or union. Attempt to
2380 // interpret the unnamed member as a DICompositeType possibly wrapped in
2381 // qualifier types. Add all the indirect fields to the current record if that
2382 // succeeds, and drop the member if that fails.
2383 assert((DDTy->getOffsetInBits() % 8) == 0 && "Unnamed bitfield member!");
2384 uint64_t Offset = DDTy->getOffsetInBits();
2385 const DIType *Ty = DDTy->getBaseType();
2386 bool FullyResolved = false;
2387 while (!FullyResolved) {
2388 switch (Ty->getTag()) {
2389 case dwarf::DW_TAG_const_type:
2390 case dwarf::DW_TAG_volatile_type:
2391 // FIXME: we should apply the qualifier types to the indirect fields
2392 // rather than dropping them.
2393 Ty = cast<DIDerivedType>(Val: Ty)->getBaseType();
2394 break;
2395 default:
2396 FullyResolved = true;
2397 break;
2398 }
2399 }
2400
2401 const DICompositeType *DCTy = dyn_cast<DICompositeType>(Val: Ty);
2402 if (!DCTy)
2403 return;
2404
2405 ClassInfo NestedInfo = collectClassInfo(Ty: DCTy);
2406 for (const ClassInfo::MemberInfo &IndirectField : NestedInfo.Members)
2407 Info.Members.push_back(
2408 x: {.MemberTypeNode: IndirectField.MemberTypeNode, .BaseOffset: IndirectField.BaseOffset + Offset});
2409}
2410
2411ClassInfo CodeViewDebug::collectClassInfo(const DICompositeType *Ty) {
2412 ClassInfo Info;
2413 // Add elements to structure type.
2414 DINodeArray Elements = Ty->getElements();
2415 for (auto *Element : Elements) {
2416 // We assume that the frontend provides all members in source declaration
2417 // order, which is what MSVC does.
2418 if (!Element)
2419 continue;
2420 if (auto *SP = dyn_cast<DISubprogram>(Val: Element)) {
2421 Info.Methods[SP->getRawName()].push_back(NewVal: SP);
2422 } else if (auto *DDTy = dyn_cast<DIDerivedType>(Val: Element)) {
2423 if (DDTy->getTag() == dwarf::DW_TAG_member) {
2424 collectMemberInfo(Info, DDTy);
2425 } else if (DDTy->getTag() == dwarf::DW_TAG_inheritance) {
2426 Info.Inheritance.push_back(x: DDTy);
2427 } else if (DDTy->getTag() == dwarf::DW_TAG_pointer_type &&
2428 DDTy->getName() == "__vtbl_ptr_type") {
2429 Info.VShapeTI = getTypeIndex(Ty: DDTy);
2430 } else if (DDTy->getTag() == dwarf::DW_TAG_typedef) {
2431 Info.NestedTypes.push_back(x: DDTy);
2432 } else if (DDTy->getTag() == dwarf::DW_TAG_friend) {
2433 // Ignore friend members. It appears that MSVC emitted info about
2434 // friends in the past, but modern versions do not.
2435 }
2436 } else if (auto *Composite = dyn_cast<DICompositeType>(Val: Element)) {
2437 Info.NestedTypes.push_back(x: Composite);
2438 }
2439 // Skip other unrecognized kinds of elements.
2440 }
2441 return Info;
2442}
2443
2444static bool shouldAlwaysEmitCompleteClassType(const DICompositeType *Ty) {
2445 // This routine is used by lowerTypeClass and lowerTypeUnion to determine
2446 // if a complete type should be emitted instead of a forward reference.
2447 return Ty->getName().empty() && Ty->getIdentifier().empty() &&
2448 !Ty->isForwardDecl();
2449}
2450
2451TypeIndex CodeViewDebug::lowerTypeClass(const DICompositeType *Ty) {
2452 // Emit the complete type for unnamed structs. C++ classes with methods
2453 // which have a circular reference back to the class type are expected to
2454 // be named by the front-end and should not be "unnamed". C unnamed
2455 // structs should not have circular references.
2456 if (shouldAlwaysEmitCompleteClassType(Ty)) {
2457 // If this unnamed complete type is already in the process of being defined
2458 // then the description of the type is malformed and cannot be emitted
2459 // into CodeView correctly so report a fatal error.
2460 auto I = CompleteTypeIndices.find(Val: Ty);
2461 if (I != CompleteTypeIndices.end() && I->second == TypeIndex())
2462 report_fatal_error(reason: "cannot debug circular reference to unnamed type");
2463 return getCompleteTypeIndex(Ty);
2464 }
2465
2466 // First, construct the forward decl. Don't look into Ty to compute the
2467 // forward decl options, since it might not be available in all TUs.
2468 TypeRecordKind Kind = getRecordKind(Ty);
2469 ClassOptions CO =
2470 ClassOptions::ForwardReference | getCommonClassOptions(Ty);
2471 std::string FullName = getFullyQualifiedName(Ty);
2472 ClassRecord CR(Kind, 0, CO, TypeIndex(), TypeIndex(), TypeIndex(), 0,
2473 FullName, Ty->getIdentifier());
2474 TypeIndex FwdDeclTI = TypeTable.writeLeafType(Record&: CR);
2475 if (!Ty->isForwardDecl())
2476 DeferredCompleteTypes.push_back(Elt: Ty);
2477 return FwdDeclTI;
2478}
2479
2480TypeIndex CodeViewDebug::lowerCompleteTypeClass(const DICompositeType *Ty) {
2481 // Construct the field list and complete type record.
2482 TypeRecordKind Kind = getRecordKind(Ty);
2483 ClassOptions CO = getCommonClassOptions(Ty);
2484 TypeIndex FieldTI;
2485 TypeIndex VShapeTI;
2486 unsigned FieldCount;
2487 bool ContainsNestedClass;
2488 std::tie(args&: FieldTI, args&: VShapeTI, args&: FieldCount, args&: ContainsNestedClass) =
2489 lowerRecordFieldList(Ty);
2490
2491 if (ContainsNestedClass)
2492 CO |= ClassOptions::ContainsNestedClass;
2493
2494 // MSVC appears to set this flag by searching any destructor or method with
2495 // FunctionOptions::Constructor among the emitted members. Clang AST has all
2496 // the members, however special member functions are not yet emitted into
2497 // debug information. For now checking a class's non-triviality seems enough.
2498 // FIXME: not true for a nested unnamed struct.
2499 if (isNonTrivial(DCTy: Ty))
2500 CO |= ClassOptions::HasConstructorOrDestructor;
2501
2502 std::string FullName = getFullyQualifiedName(Ty);
2503
2504 uint64_t SizeInBytes = Ty->getSizeInBits() / 8;
2505
2506 ClassRecord CR(Kind, FieldCount, CO, FieldTI, TypeIndex(), VShapeTI,
2507 SizeInBytes, FullName, Ty->getIdentifier());
2508 TypeIndex ClassTI = TypeTable.writeLeafType(Record&: CR);
2509
2510 addUDTSrcLine(Ty, TI: ClassTI);
2511
2512 addToUDTs(Ty);
2513
2514 return ClassTI;
2515}
2516
2517TypeIndex CodeViewDebug::lowerTypeUnion(const DICompositeType *Ty) {
2518 // Emit the complete type for unnamed unions.
2519 if (shouldAlwaysEmitCompleteClassType(Ty))
2520 return getCompleteTypeIndex(Ty);
2521
2522 ClassOptions CO =
2523 ClassOptions::ForwardReference | getCommonClassOptions(Ty);
2524 std::string FullName = getFullyQualifiedName(Ty);
2525 UnionRecord UR(0, CO, TypeIndex(), 0, FullName, Ty->getIdentifier());
2526 TypeIndex FwdDeclTI = TypeTable.writeLeafType(Record&: UR);
2527 if (!Ty->isForwardDecl())
2528 DeferredCompleteTypes.push_back(Elt: Ty);
2529 return FwdDeclTI;
2530}
2531
2532TypeIndex CodeViewDebug::lowerCompleteTypeUnion(const DICompositeType *Ty) {
2533 ClassOptions CO = ClassOptions::Sealed | getCommonClassOptions(Ty);
2534 TypeIndex FieldTI;
2535 unsigned FieldCount;
2536 bool ContainsNestedClass;
2537 std::tie(args&: FieldTI, args: std::ignore, args&: FieldCount, args&: ContainsNestedClass) =
2538 lowerRecordFieldList(Ty);
2539
2540 if (ContainsNestedClass)
2541 CO |= ClassOptions::ContainsNestedClass;
2542
2543 uint64_t SizeInBytes = Ty->getSizeInBits() / 8;
2544 std::string FullName = getFullyQualifiedName(Ty);
2545
2546 UnionRecord UR(FieldCount, CO, FieldTI, SizeInBytes, FullName,
2547 Ty->getIdentifier());
2548 TypeIndex UnionTI = TypeTable.writeLeafType(Record&: UR);
2549
2550 addUDTSrcLine(Ty, TI: UnionTI);
2551
2552 addToUDTs(Ty);
2553
2554 return UnionTI;
2555}
2556
2557std::tuple<TypeIndex, TypeIndex, unsigned, bool>
2558CodeViewDebug::lowerRecordFieldList(const DICompositeType *Ty) {
2559 // Manually count members. MSVC appears to count everything that generates a
2560 // field list record. Each individual overload in a method overload group
2561 // contributes to this count, even though the overload group is a single field
2562 // list record.
2563 unsigned MemberCount = 0;
2564 ClassInfo Info = collectClassInfo(Ty);
2565 ContinuationRecordBuilder ContinuationBuilder;
2566 ContinuationBuilder.begin(RecordKind: ContinuationRecordKind::FieldList);
2567
2568 // Create base classes.
2569 for (const DIDerivedType *I : Info.Inheritance) {
2570 if (I->getFlags() & DINode::FlagVirtual) {
2571 // Virtual base.
2572 unsigned VBPtrOffset = I->getVBPtrOffset();
2573 // FIXME: Despite the accessor name, the offset is really in bytes.
2574 unsigned VBTableIndex = I->getOffsetInBits() / 4;
2575 auto RecordKind = (I->getFlags() & DINode::FlagIndirectVirtualBase) == DINode::FlagIndirectVirtualBase
2576 ? TypeRecordKind::IndirectVirtualBaseClass
2577 : TypeRecordKind::VirtualBaseClass;
2578 VirtualBaseClassRecord VBCR(
2579 RecordKind, translateAccessFlags(RecordTag: Ty->getTag(), Flags: I->getFlags()),
2580 getTypeIndex(Ty: I->getBaseType()), getVBPTypeIndex(), VBPtrOffset,
2581 VBTableIndex);
2582
2583 ContinuationBuilder.writeMemberType(Record&: VBCR);
2584 MemberCount++;
2585 } else {
2586 assert(I->getOffsetInBits() % 8 == 0 &&
2587 "bases must be on byte boundaries");
2588 BaseClassRecord BCR(translateAccessFlags(RecordTag: Ty->getTag(), Flags: I->getFlags()),
2589 getTypeIndex(Ty: I->getBaseType()),
2590 I->getOffsetInBits() / 8);
2591 ContinuationBuilder.writeMemberType(Record&: BCR);
2592 MemberCount++;
2593 }
2594 }
2595
2596 // Create members.
2597 for (ClassInfo::MemberInfo &MemberInfo : Info.Members) {
2598 const DIDerivedType *Member = MemberInfo.MemberTypeNode;
2599 TypeIndex MemberBaseType = getTypeIndex(Ty: Member->getBaseType());
2600 StringRef MemberName = Member->getName();
2601 MemberAccess Access =
2602 translateAccessFlags(RecordTag: Ty->getTag(), Flags: Member->getFlags());
2603
2604 if (Member->isStaticMember()) {
2605 StaticDataMemberRecord SDMR(Access, MemberBaseType, MemberName);
2606 ContinuationBuilder.writeMemberType(Record&: SDMR);
2607 MemberCount++;
2608 continue;
2609 }
2610
2611 // Virtual function pointer member.
2612 if ((Member->getFlags() & DINode::FlagArtificial) &&
2613 Member->getName().starts_with(Prefix: "_vptr$")) {
2614 VFPtrRecord VFPR(getTypeIndex(Ty: Member->getBaseType()));
2615 ContinuationBuilder.writeMemberType(Record&: VFPR);
2616 MemberCount++;
2617 continue;
2618 }
2619
2620 // Data member.
2621 uint64_t MemberOffsetInBits =
2622 Member->getOffsetInBits() + MemberInfo.BaseOffset;
2623 if (Member->isBitField()) {
2624 uint64_t StartBitOffset = MemberOffsetInBits;
2625 if (const auto *CI =
2626 dyn_cast_or_null<ConstantInt>(Val: Member->getStorageOffsetInBits())) {
2627 MemberOffsetInBits = CI->getZExtValue() + MemberInfo.BaseOffset;
2628 }
2629 StartBitOffset -= MemberOffsetInBits;
2630 BitFieldRecord BFR(MemberBaseType, Member->getSizeInBits(),
2631 StartBitOffset);
2632 MemberBaseType = TypeTable.writeLeafType(Record&: BFR);
2633 }
2634 uint64_t MemberOffsetInBytes = MemberOffsetInBits / 8;
2635 DataMemberRecord DMR(Access, MemberBaseType, MemberOffsetInBytes,
2636 MemberName);
2637 ContinuationBuilder.writeMemberType(Record&: DMR);
2638 MemberCount++;
2639 }
2640
2641 // Create methods
2642 for (auto &MethodItr : Info.Methods) {
2643 StringRef Name = MethodItr.first->getString();
2644
2645 std::vector<OneMethodRecord> Methods;
2646 for (const DISubprogram *SP : MethodItr.second) {
2647 TypeIndex MethodType = getMemberFunctionType(SP, Class: Ty);
2648 bool Introduced = SP->getFlags() & DINode::FlagIntroducedVirtual;
2649
2650 unsigned VFTableOffset = -1;
2651 if (Introduced)
2652 VFTableOffset = SP->getVirtualIndex() * getPointerSizeInBytes();
2653
2654 Methods.push_back(x: OneMethodRecord(
2655 MethodType, translateAccessFlags(RecordTag: Ty->getTag(), Flags: SP->getFlags()),
2656 translateMethodKindFlags(SP, Introduced),
2657 translateMethodOptionFlags(SP), VFTableOffset, Name));
2658 MemberCount++;
2659 }
2660 assert(!Methods.empty() && "Empty methods map entry");
2661 if (Methods.size() == 1)
2662 ContinuationBuilder.writeMemberType(Record&: Methods[0]);
2663 else {
2664 // FIXME: Make this use its own ContinuationBuilder so that
2665 // MethodOverloadList can be split correctly.
2666 MethodOverloadListRecord MOLR(Methods);
2667 TypeIndex MethodList = TypeTable.writeLeafType(Record&: MOLR);
2668
2669 OverloadedMethodRecord OMR(Methods.size(), MethodList, Name);
2670 ContinuationBuilder.writeMemberType(Record&: OMR);
2671 }
2672 }
2673
2674 // Create nested classes.
2675 for (const DIType *Nested : Info.NestedTypes) {
2676 NestedTypeRecord R(getTypeIndex(Ty: Nested), Nested->getName());
2677 ContinuationBuilder.writeMemberType(Record&: R);
2678 MemberCount++;
2679 }
2680
2681 TypeIndex FieldTI = TypeTable.insertRecord(Builder&: ContinuationBuilder);
2682 return std::make_tuple(args&: FieldTI, args&: Info.VShapeTI, args&: MemberCount,
2683 args: !Info.NestedTypes.empty());
2684}
2685
2686TypeIndex CodeViewDebug::getVBPTypeIndex() {
2687 if (!VBPType.getIndex()) {
2688 // Make a 'const int *' type.
2689 ModifierRecord MR(TypeIndex::Int32(), ModifierOptions::Const);
2690 TypeIndex ModifiedTI = TypeTable.writeLeafType(Record&: MR);
2691
2692 PointerKind PK = getPointerSizeInBytes() == 8 ? PointerKind::Near64
2693 : PointerKind::Near32;
2694 PointerMode PM = PointerMode::Pointer;
2695 PointerOptions PO = PointerOptions::None;
2696 PointerRecord PR(ModifiedTI, PK, PM, PO, getPointerSizeInBytes());
2697 VBPType = TypeTable.writeLeafType(Record&: PR);
2698 }
2699
2700 return VBPType;
2701}
2702
2703TypeIndex CodeViewDebug::getTypeIndex(const DIType *Ty, const DIType *ClassTy) {
2704 // The null DIType is the void type. Don't try to hash it.
2705 if (!Ty)
2706 return TypeIndex::Void();
2707
2708 // Check if we've already translated this type. Don't try to do a
2709 // get-or-create style insertion that caches the hash lookup across the
2710 // lowerType call. It will update the TypeIndices map.
2711 auto I = TypeIndices.find(Val: {Ty, ClassTy});
2712 if (I != TypeIndices.end())
2713 return I->second;
2714
2715 TypeLoweringScope S(*this);
2716 TypeIndex TI = lowerType(Ty, ClassTy);
2717 return recordTypeIndexForDINode(Node: Ty, TI, ClassTy);
2718}
2719
2720codeview::TypeIndex
2721CodeViewDebug::getTypeIndexForThisPtr(const DIDerivedType *PtrTy,
2722 const DISubroutineType *SubroutineTy) {
2723 assert(PtrTy->getTag() == dwarf::DW_TAG_pointer_type &&
2724 "this type must be a pointer type");
2725
2726 PointerOptions Options = PointerOptions::None;
2727 if (SubroutineTy->getFlags() & DINode::DIFlags::FlagLValueReference)
2728 Options = PointerOptions::LValueRefThisPointer;
2729 else if (SubroutineTy->getFlags() & DINode::DIFlags::FlagRValueReference)
2730 Options = PointerOptions::RValueRefThisPointer;
2731
2732 // Check if we've already translated this type. If there is no ref qualifier
2733 // on the function then we look up this pointer type with no associated class
2734 // so that the TypeIndex for the this pointer can be shared with the type
2735 // index for other pointers to this class type. If there is a ref qualifier
2736 // then we lookup the pointer using the subroutine as the parent type.
2737 auto I = TypeIndices.find(Val: {PtrTy, SubroutineTy});
2738 if (I != TypeIndices.end())
2739 return I->second;
2740
2741 TypeLoweringScope S(*this);
2742 TypeIndex TI = lowerTypePointer(Ty: PtrTy, PO: Options);
2743 return recordTypeIndexForDINode(Node: PtrTy, TI, ClassTy: SubroutineTy);
2744}
2745
2746TypeIndex CodeViewDebug::getTypeIndexForReferenceTo(const DIType *Ty) {
2747 PointerRecord PR(getTypeIndex(Ty),
2748 getPointerSizeInBytes() == 8 ? PointerKind::Near64
2749 : PointerKind::Near32,
2750 PointerMode::LValueReference, PointerOptions::None,
2751 Ty->getSizeInBits() / 8);
2752 return TypeTable.writeLeafType(Record&: PR);
2753}
2754
2755TypeIndex CodeViewDebug::getCompleteTypeIndex(const DIType *Ty) {
2756 // The null DIType is the void type. Don't try to hash it.
2757 if (!Ty)
2758 return TypeIndex::Void();
2759
2760 // Look through typedefs when getting the complete type index. Call
2761 // getTypeIndex on the typdef to ensure that any UDTs are accumulated and are
2762 // emitted only once.
2763 if (Ty->getTag() == dwarf::DW_TAG_typedef)
2764 (void)getTypeIndex(Ty);
2765 while (Ty->getTag() == dwarf::DW_TAG_typedef)
2766 Ty = cast<DIDerivedType>(Val: Ty)->getBaseType();
2767
2768 // If this is a non-record type, the complete type index is the same as the
2769 // normal type index. Just call getTypeIndex.
2770 switch (Ty->getTag()) {
2771 case dwarf::DW_TAG_class_type:
2772 case dwarf::DW_TAG_structure_type:
2773 case dwarf::DW_TAG_union_type:
2774 break;
2775 default:
2776 return getTypeIndex(Ty);
2777 }
2778
2779 const auto *CTy = cast<DICompositeType>(Val: Ty);
2780
2781 TypeLoweringScope S(*this);
2782
2783 // Make sure the forward declaration is emitted first. It's unclear if this
2784 // is necessary, but MSVC does it, and we should follow suit until we can show
2785 // otherwise.
2786 // We only emit a forward declaration for named types.
2787 if (!CTy->getName().empty() || !CTy->getIdentifier().empty()) {
2788 TypeIndex FwdDeclTI = getTypeIndex(Ty: CTy);
2789
2790 // Just use the forward decl if we don't have complete type info. This
2791 // might happen if the frontend is using modules and expects the complete
2792 // definition to be emitted elsewhere.
2793 if (CTy->isForwardDecl())
2794 return FwdDeclTI;
2795 }
2796
2797 // Check if we've already translated the complete record type.
2798 // Insert the type with a null TypeIndex to signify that the type is currently
2799 // being lowered.
2800 auto InsertResult = CompleteTypeIndices.try_emplace(Key: CTy);
2801 if (!InsertResult.second)
2802 return InsertResult.first->second;
2803
2804 TypeIndex TI;
2805 switch (CTy->getTag()) {
2806 case dwarf::DW_TAG_class_type:
2807 case dwarf::DW_TAG_structure_type:
2808 TI = lowerCompleteTypeClass(Ty: CTy);
2809 break;
2810 case dwarf::DW_TAG_union_type:
2811 TI = lowerCompleteTypeUnion(Ty: CTy);
2812 break;
2813 default:
2814 llvm_unreachable("not a record");
2815 }
2816
2817 // Update the type index associated with this CompositeType. This cannot
2818 // use the 'InsertResult' iterator above because it is potentially
2819 // invalidated by map insertions which can occur while lowering the class
2820 // type above.
2821 CompleteTypeIndices[CTy] = TI;
2822 return TI;
2823}
2824
2825/// Emit all the deferred complete record types. Try to do this in FIFO order,
2826/// and do this until fixpoint, as each complete record type typically
2827/// references
2828/// many other record types.
2829void CodeViewDebug::emitDeferredCompleteTypes() {
2830 SmallVector<const DICompositeType *, 4> TypesToEmit;
2831 while (!DeferredCompleteTypes.empty()) {
2832 std::swap(LHS&: DeferredCompleteTypes, RHS&: TypesToEmit);
2833 for (const DICompositeType *RecordTy : TypesToEmit)
2834 getCompleteTypeIndex(Ty: RecordTy);
2835 TypesToEmit.clear();
2836 }
2837}
2838
2839void CodeViewDebug::emitLocalVariableList(const FunctionInfo &FI,
2840 ArrayRef<LocalVariable> Locals) {
2841 // Get the sorted list of parameters and emit them first.
2842 SmallVector<const LocalVariable *, 6> Params;
2843 for (const LocalVariable &L : Locals)
2844 if (L.DIVar->isParameter())
2845 Params.push_back(Elt: &L);
2846 llvm::sort(C&: Params, Comp: [](const LocalVariable *L, const LocalVariable *R) {
2847 return L->DIVar->getArg() < R->DIVar->getArg();
2848 });
2849 for (const LocalVariable *L : Params)
2850 emitLocalVariable(FI, Var: *L);
2851
2852 // Next emit all non-parameters in the order that we found them.
2853 for (const LocalVariable &L : Locals) {
2854 if (!L.DIVar->isParameter()) {
2855 if (L.ConstantValue) {
2856 // If ConstantValue is set we will emit it as a S_CONSTANT instead of a
2857 // S_LOCAL in order to be able to represent it at all.
2858 const DIType *Ty = L.DIVar->getType();
2859 APSInt Val(*L.ConstantValue);
2860 emitConstantSymbolRecord(DTy: Ty, Value&: Val, QualifiedName: std::string(L.DIVar->getName()));
2861 } else {
2862 emitLocalVariable(FI, Var: L);
2863 }
2864 }
2865 }
2866}
2867
2868void CodeViewDebug::emitLocalVariable(const FunctionInfo &FI,
2869 const LocalVariable &Var) {
2870 // LocalSym record, see SymbolRecord.h for more info.
2871 MCSymbol *LocalEnd = beginSymbolRecord(Kind: SymbolKind::S_LOCAL);
2872
2873 LocalSymFlags Flags = LocalSymFlags::None;
2874 if (Var.DIVar->isParameter())
2875 Flags |= LocalSymFlags::IsParameter;
2876 if (Var.DefRanges.empty())
2877 Flags |= LocalSymFlags::IsOptimizedOut;
2878
2879 OS.AddComment(T: "TypeIndex");
2880 TypeIndex TI = Var.UseReferenceType
2881 ? getTypeIndexForReferenceTo(Ty: Var.DIVar->getType())
2882 : getCompleteTypeIndex(Ty: Var.DIVar->getType());
2883 OS.emitInt32(Value: TI.getIndex());
2884 OS.AddComment(T: "Flags");
2885 OS.emitInt16(Value: static_cast<uint16_t>(Flags));
2886 // Truncate the name so we won't overflow the record length field.
2887 emitNullTerminatedSymbolName(OS, S: Var.DIVar->getName());
2888 endSymbolRecord(SymEnd: LocalEnd);
2889
2890 // Calculate the on disk prefix of the appropriate def range record. The
2891 // records and on disk formats are described in SymbolRecords.h. BytePrefix
2892 // should be big enough to hold all forms without memory allocation.
2893 SmallString<20> BytePrefix;
2894 for (const auto &Pair : Var.DefRanges) {
2895 LocalVarDef DefRange = Pair.first;
2896 const auto &Ranges = Pair.second;
2897 BytePrefix.clear();
2898 if (DefRange.InMemory) {
2899 int Offset = DefRange.DataOffset;
2900 unsigned Reg = DefRange.CVRegister;
2901
2902 // 32-bit x86 call sequences often use PUSH instructions, which disrupt
2903 // ESP-relative offsets. Use the virtual frame pointer, VFRAME or $T0,
2904 // instead. In frames without stack realignment, $T0 will be the CFA.
2905 if (RegisterId(Reg) == RegisterId::ESP) {
2906 Reg = unsigned(RegisterId::VFRAME);
2907 Offset += FI.OffsetAdjustment;
2908 }
2909
2910 // If we can use the chosen frame pointer for the frame and this isn't a
2911 // sliced aggregate, use the smaller S_DEFRANGE_FRAMEPOINTER_REL record.
2912 // Otherwise, use S_DEFRANGE_REGISTER_REL.
2913 EncodedFramePtrReg EncFP = encodeFramePtrReg(Reg: RegisterId(Reg), CPU: TheCPU);
2914 if (!DefRange.IsSubfield && EncFP != EncodedFramePtrReg::None &&
2915 (bool(Flags & LocalSymFlags::IsParameter)
2916 ? (EncFP == FI.EncodedParamFramePtrReg)
2917 : (EncFP == FI.EncodedLocalFramePtrReg))) {
2918 DefRangeFramePointerRelHeader DRHdr;
2919 DRHdr.Offset = Offset;
2920 OS.emitCVDefRangeDirective(Ranges, DRHdr);
2921 } else {
2922 uint16_t RegRelFlags = 0;
2923 if (DefRange.IsSubfield) {
2924 RegRelFlags = DefRangeRegisterRelSym::IsSubfieldFlag |
2925 (DefRange.StructOffset
2926 << DefRangeRegisterRelSym::OffsetInParentShift);
2927 }
2928 DefRangeRegisterRelHeader DRHdr;
2929 DRHdr.Register = Reg;
2930 DRHdr.Flags = RegRelFlags;
2931 DRHdr.BasePointerOffset = Offset;
2932 OS.emitCVDefRangeDirective(Ranges, DRHdr);
2933 }
2934 } else {
2935 assert(DefRange.DataOffset == 0 && "unexpected offset into register");
2936 if (DefRange.IsSubfield) {
2937 DefRangeSubfieldRegisterHeader DRHdr;
2938 DRHdr.Register = DefRange.CVRegister;
2939 DRHdr.MayHaveNoName = 0;
2940 DRHdr.OffsetInParent = DefRange.StructOffset;
2941 OS.emitCVDefRangeDirective(Ranges, DRHdr);
2942 } else {
2943 DefRangeRegisterHeader DRHdr;
2944 DRHdr.Register = DefRange.CVRegister;
2945 DRHdr.MayHaveNoName = 0;
2946 OS.emitCVDefRangeDirective(Ranges, DRHdr);
2947 }
2948 }
2949 }
2950}
2951
2952void CodeViewDebug::emitLexicalBlockList(ArrayRef<LexicalBlock *> Blocks,
2953 const FunctionInfo& FI) {
2954 for (LexicalBlock *Block : Blocks)
2955 emitLexicalBlock(Block: *Block, FI);
2956}
2957
2958/// Emit an S_BLOCK32 and S_END record pair delimiting the contents of a
2959/// lexical block scope.
2960void CodeViewDebug::emitLexicalBlock(const LexicalBlock &Block,
2961 const FunctionInfo& FI) {
2962 MCSymbol *RecordEnd = beginSymbolRecord(Kind: SymbolKind::S_BLOCK32);
2963 OS.AddComment(T: "PtrParent");
2964 OS.emitInt32(Value: 0); // PtrParent
2965 OS.AddComment(T: "PtrEnd");
2966 OS.emitInt32(Value: 0); // PtrEnd
2967 OS.AddComment(T: "Code size");
2968 OS.emitAbsoluteSymbolDiff(Hi: Block.End, Lo: Block.Begin, Size: 4); // Code Size
2969 OS.AddComment(T: "Function section relative address");
2970 OS.emitCOFFSecRel32(Symbol: Block.Begin, /*Offset=*/0); // Func Offset
2971 OS.AddComment(T: "Function section index");
2972 OS.emitCOFFSectionIndex(Symbol: FI.Begin); // Func Symbol
2973 OS.AddComment(T: "Lexical block name");
2974 emitNullTerminatedSymbolName(OS, S: Block.Name); // Name
2975 endSymbolRecord(SymEnd: RecordEnd);
2976
2977 // Emit variables local to this lexical block.
2978 emitLocalVariableList(FI, Locals: Block.Locals);
2979 emitGlobalVariableList(Globals: Block.Globals);
2980
2981 // Emit lexical blocks contained within this block.
2982 emitLexicalBlockList(Blocks: Block.Children, FI);
2983
2984 // Close the lexical block scope.
2985 emitEndSymbolRecord(EndKind: SymbolKind::S_END);
2986}
2987
2988/// Convenience routine for collecting lexical block information for a list
2989/// of lexical scopes.
2990void CodeViewDebug::collectLexicalBlockInfo(
2991 SmallVectorImpl<LexicalScope *> &Scopes,
2992 SmallVectorImpl<LexicalBlock *> &Blocks,
2993 SmallVectorImpl<LocalVariable> &Locals,
2994 SmallVectorImpl<CVGlobalVariable> &Globals) {
2995 for (LexicalScope *Scope : Scopes)
2996 collectLexicalBlockInfo(Scope&: *Scope, ParentBlocks&: Blocks, ParentLocals&: Locals, ParentGlobals&: Globals);
2997}
2998
2999/// Populate the lexical blocks and local variable lists of the parent with
3000/// information about the specified lexical scope.
3001void CodeViewDebug::collectLexicalBlockInfo(
3002 LexicalScope &Scope,
3003 SmallVectorImpl<LexicalBlock *> &ParentBlocks,
3004 SmallVectorImpl<LocalVariable> &ParentLocals,
3005 SmallVectorImpl<CVGlobalVariable> &ParentGlobals) {
3006 if (Scope.isAbstractScope())
3007 return;
3008
3009 // Gather information about the lexical scope including local variables,
3010 // global variables, and address ranges.
3011 bool IgnoreScope = false;
3012 auto LI = ScopeVariables.find(Val: &Scope);
3013 SmallVectorImpl<LocalVariable> *Locals =
3014 LI != ScopeVariables.end() ? &LI->second : nullptr;
3015 auto GI = ScopeGlobals.find(Val: Scope.getScopeNode());
3016 SmallVectorImpl<CVGlobalVariable> *Globals =
3017 GI != ScopeGlobals.end() ? GI->second.get() : nullptr;
3018 const DILexicalBlock *DILB = dyn_cast<DILexicalBlock>(Val: Scope.getScopeNode());
3019 const SmallVectorImpl<InsnRange> &Ranges = Scope.getRanges();
3020
3021 // Ignore lexical scopes which do not contain variables.
3022 if (!Locals && !Globals)
3023 IgnoreScope = true;
3024
3025 // Ignore lexical scopes which are not lexical blocks.
3026 if (!DILB)
3027 IgnoreScope = true;
3028
3029 // Ignore scopes which have too many address ranges to represent in the
3030 // current CodeView format or do not have a valid address range.
3031 //
3032 // For lexical scopes with multiple address ranges you may be tempted to
3033 // construct a single range covering every instruction where the block is
3034 // live and everything in between. Unfortunately, Visual Studio only
3035 // displays variables from the first matching lexical block scope. If the
3036 // first lexical block contains exception handling code or cold code which
3037 // is moved to the bottom of the routine creating a single range covering
3038 // nearly the entire routine, then it will hide all other lexical blocks
3039 // and the variables they contain.
3040 if (Ranges.size() != 1 || !getLabelAfterInsn(MI: Ranges.front().second))
3041 IgnoreScope = true;
3042
3043 if (IgnoreScope) {
3044 // This scope can be safely ignored and eliminating it will reduce the
3045 // size of the debug information. Be sure to collect any variable and scope
3046 // information from the this scope or any of its children and collapse them
3047 // into the parent scope.
3048 if (Locals)
3049 ParentLocals.append(in_start: Locals->begin(), in_end: Locals->end());
3050 if (Globals)
3051 ParentGlobals.append(in_start: Globals->begin(), in_end: Globals->end());
3052 collectLexicalBlockInfo(Scopes&: Scope.getChildren(),
3053 Blocks&: ParentBlocks,
3054 Locals&: ParentLocals,
3055 Globals&: ParentGlobals);
3056 return;
3057 }
3058
3059 // Create a new CodeView lexical block for this lexical scope. If we've
3060 // seen this DILexicalBlock before then the scope tree is malformed and
3061 // we can handle this gracefully by not processing it a second time.
3062 auto BlockInsertion = CurFn->LexicalBlocks.try_emplace(k: DILB);
3063 if (!BlockInsertion.second)
3064 return;
3065
3066 // Create a lexical block containing the variables and collect the
3067 // lexical block information for the children.
3068 const InsnRange &Range = Ranges.front();
3069 assert(Range.first && Range.second);
3070 LexicalBlock &Block = BlockInsertion.first->second;
3071 Block.Begin = getLabelBeforeInsn(MI: Range.first);
3072 Block.End = getLabelAfterInsn(MI: Range.second);
3073 assert(Block.Begin && "missing label for scope begin");
3074 assert(Block.End && "missing label for scope end");
3075 Block.Name = DILB->getName();
3076 if (Locals)
3077 Block.Locals = std::move(*Locals);
3078 if (Globals)
3079 Block.Globals = std::move(*Globals);
3080 ParentBlocks.push_back(Elt: &Block);
3081 collectLexicalBlockInfo(Scopes&: Scope.getChildren(),
3082 Blocks&: Block.Children,
3083 Locals&: Block.Locals,
3084 Globals&: Block.Globals);
3085}
3086
3087void CodeViewDebug::endFunctionImpl(const MachineFunction *MF) {
3088 const Function &GV = MF->getFunction();
3089 assert(FnDebugInfo.count(&GV));
3090 assert(CurFn == FnDebugInfo[&GV].get());
3091
3092 collectVariableInfo(SP: GV.getSubprogram());
3093
3094 // Build the lexical block structure to emit for this routine.
3095 if (LexicalScope *CFS = LScopes.getCurrentFunctionScope())
3096 collectLexicalBlockInfo(Scope&: *CFS,
3097 ParentBlocks&: CurFn->ChildBlocks,
3098 ParentLocals&: CurFn->Locals,
3099 ParentGlobals&: CurFn->Globals);
3100
3101 // Clear the scope and variable information from the map which will not be
3102 // valid after we have finished processing this routine. This also prepares
3103 // the map for the subsequent routine.
3104 ScopeVariables.clear();
3105
3106 // Don't emit anything if we don't have any line tables.
3107 // Thunks are compiler-generated and probably won't have source correlation.
3108 if (!CurFn->HaveLineInfo && !GV.getSubprogram()->isThunk()) {
3109 FnDebugInfo.erase(Key: &GV);
3110 CurFn = nullptr;
3111 return;
3112 }
3113
3114 // Find heap alloc sites and add to list.
3115 for (const auto &MBB : *MF) {
3116 for (const auto &MI : MBB) {
3117 if (MDNode *MD = MI.getHeapAllocMarker()) {
3118 CurFn->HeapAllocSites.push_back(x: std::make_tuple(args: getLabelBeforeInsn(MI: &MI),
3119 args: getLabelAfterInsn(MI: &MI),
3120 args: dyn_cast<DIType>(Val: MD)));
3121 }
3122 }
3123 }
3124
3125 bool isThumb = MMI->getModule()->getTargetTriple().getArch() ==
3126 llvm::Triple::ArchType::thumb;
3127 collectDebugInfoForJumpTables(MF, isThumb);
3128
3129 CurFn->Annotations = MF->getCodeViewAnnotations();
3130
3131 CurFn->End = Asm->getFunctionEnd();
3132
3133 CurFn = nullptr;
3134}
3135
3136// Usable locations are valid with non-zero line numbers. A line number of zero
3137// corresponds to optimized code that doesn't have a distinct source location.
3138// In this case, we try to use the previous or next source location depending on
3139// the context.
3140static bool isUsableDebugLoc(DebugLoc DL) {
3141 return DL && DL.getLine() != 0;
3142}
3143
3144void CodeViewDebug::beginInstruction(const MachineInstr *MI) {
3145 DebugHandlerBase::beginInstruction(MI);
3146
3147 // Ignore DBG_VALUE and DBG_LABEL locations and function prologue.
3148 if (!Asm || !CurFn || MI->isDebugInstr() ||
3149 MI->getFlag(Flag: MachineInstr::FrameSetup))
3150 return;
3151
3152 // If the first instruction of a new MBB has no location, find the first
3153 // instruction with a location and use that.
3154 DebugLoc DL = MI->getDebugLoc();
3155 if (!isUsableDebugLoc(DL) && MI->getParent() != PrevInstBB) {
3156 for (const auto &NextMI : *MI->getParent()) {
3157 if (NextMI.isDebugInstr())
3158 continue;
3159 DL = NextMI.getDebugLoc();
3160 if (isUsableDebugLoc(DL))
3161 break;
3162 }
3163 // FIXME: Handle the case where the BB has no valid locations. This would
3164 // probably require doing a real dataflow analysis.
3165 }
3166 PrevInstBB = MI->getParent();
3167
3168 // If we still don't have a debug location, don't record a location.
3169 if (!isUsableDebugLoc(DL))
3170 return;
3171
3172 maybeRecordLocation(DL, MF: Asm->MF);
3173}
3174
3175MCSymbol *CodeViewDebug::beginCVSubsection(DebugSubsectionKind Kind) {
3176 MCSymbol *BeginLabel = MMI->getContext().createTempSymbol(),
3177 *EndLabel = MMI->getContext().createTempSymbol();
3178 OS.emitInt32(Value: unsigned(Kind));
3179 OS.AddComment(T: "Subsection size");
3180 OS.emitAbsoluteSymbolDiff(Hi: EndLabel, Lo: BeginLabel, Size: 4);
3181 OS.emitLabel(Symbol: BeginLabel);
3182 return EndLabel;
3183}
3184
3185void CodeViewDebug::endCVSubsection(MCSymbol *EndLabel) {
3186 OS.emitLabel(Symbol: EndLabel);
3187 // Every subsection must be aligned to a 4-byte boundary.
3188 OS.emitValueToAlignment(Alignment: Align(4));
3189}
3190
3191static StringRef getSymbolName(SymbolKind SymKind) {
3192 for (const EnumEntry<SymbolKind> &EE : getSymbolTypeNames())
3193 if (EE.Value == SymKind)
3194 return EE.Name;
3195 return "";
3196}
3197
3198MCSymbol *CodeViewDebug::beginSymbolRecord(SymbolKind SymKind) {
3199 MCSymbol *BeginLabel = MMI->getContext().createTempSymbol(),
3200 *EndLabel = MMI->getContext().createTempSymbol();
3201 OS.AddComment(T: "Record length");
3202 OS.emitAbsoluteSymbolDiff(Hi: EndLabel, Lo: BeginLabel, Size: 2);
3203 OS.emitLabel(Symbol: BeginLabel);
3204 if (OS.isVerboseAsm())
3205 OS.AddComment(T: "Record kind: " + getSymbolName(SymKind));
3206 OS.emitInt16(Value: unsigned(SymKind));
3207 return EndLabel;
3208}
3209
3210void CodeViewDebug::endSymbolRecord(MCSymbol *SymEnd) {
3211 // MSVC does not pad out symbol records to four bytes, but LLVM does to avoid
3212 // an extra copy of every symbol record in LLD. This increases object file
3213 // size by less than 1% in the clang build, and is compatible with the Visual
3214 // C++ linker.
3215 OS.emitValueToAlignment(Alignment: Align(4));
3216 OS.emitLabel(Symbol: SymEnd);
3217}
3218
3219void CodeViewDebug::emitEndSymbolRecord(SymbolKind EndKind) {
3220 OS.AddComment(T: "Record length");
3221 OS.emitInt16(Value: 2);
3222 if (OS.isVerboseAsm())
3223 OS.AddComment(T: "Record kind: " + getSymbolName(SymKind: EndKind));
3224 OS.emitInt16(Value: uint16_t(EndKind)); // Record Kind
3225}
3226
3227void CodeViewDebug::emitDebugInfoForUDTs(
3228 const std::vector<std::pair<std::string, const DIType *>> &UDTs) {
3229#ifndef NDEBUG
3230 size_t OriginalSize = UDTs.size();
3231#endif
3232 for (const auto &UDT : UDTs) {
3233 const DIType *T = UDT.second;
3234 assert(shouldEmitUdt(T));
3235 MCSymbol *UDTRecordEnd = beginSymbolRecord(SymKind: SymbolKind::S_UDT);
3236 OS.AddComment(T: "Type");
3237 OS.emitInt32(Value: getCompleteTypeIndex(Ty: T).getIndex());
3238 assert(OriginalSize == UDTs.size() &&
3239 "getCompleteTypeIndex found new UDTs!");
3240 emitNullTerminatedSymbolName(OS, S: UDT.first);
3241 endSymbolRecord(SymEnd: UDTRecordEnd);
3242 }
3243}
3244
3245void CodeViewDebug::collectGlobalVariableInfo() {
3246 DenseMap<const DIGlobalVariableExpression *, const GlobalVariable *>
3247 GlobalMap;
3248 for (const GlobalVariable &GV : MMI->getModule()->globals()) {
3249 SmallVector<DIGlobalVariableExpression *, 1> GVEs;
3250 GV.getDebugInfo(GVs&: GVEs);
3251 for (const auto *GVE : GVEs)
3252 GlobalMap[GVE] = &GV;
3253 }
3254
3255 NamedMDNode *CUs = MMI->getModule()->getNamedMetadata(Name: "llvm.dbg.cu");
3256 for (const MDNode *Node : CUs->operands()) {
3257 const auto *CU = cast<DICompileUnit>(Val: Node);
3258 for (const auto *GVE : CU->getGlobalVariables()) {
3259 const DIGlobalVariable *DIGV = GVE->getVariable();
3260 const DIExpression *DIE = GVE->getExpression();
3261 // Don't emit string literals in CodeView, as the only useful parts are
3262 // generally the filename and line number, which isn't possible to output
3263 // in CodeView. String literals should be the only unnamed GlobalVariable
3264 // with debug info.
3265 if (DIGV->getName().empty()) continue;
3266
3267 if ((DIE->getNumElements() == 2) &&
3268 (DIE->getElement(I: 0) == dwarf::DW_OP_plus_uconst))
3269 // Record the constant offset for the variable.
3270 //
3271 // A Fortran common block uses this idiom to encode the offset
3272 // of a variable from the common block's starting address.
3273 CVGlobalVariableOffsets.insert(
3274 KV: std::make_pair(x&: DIGV, y: DIE->getElement(I: 1)));
3275
3276 // Emit constant global variables in a global symbol section.
3277 if (GlobalMap.count(Val: GVE) == 0 && DIE->isConstant()) {
3278 CVGlobalVariable CVGV = {.DIGV: DIGV, .GVInfo: DIE};
3279 GlobalVariables.emplace_back(Args: std::move(CVGV));
3280 }
3281
3282 const auto *GV = GlobalMap.lookup(Val: GVE);
3283 if (!GV || GV->isDeclarationForLinker())
3284 continue;
3285
3286 DIScope *Scope = DIGV->getScope();
3287 SmallVector<CVGlobalVariable, 1> *VariableList;
3288 if (Scope && isa<DILocalScope>(Val: Scope)) {
3289 // Locate a global variable list for this scope, creating one if
3290 // necessary.
3291 auto Insertion = ScopeGlobals.insert(
3292 KV: {Scope, std::unique_ptr<GlobalVariableList>()});
3293 if (Insertion.second)
3294 Insertion.first->second = std::make_unique<GlobalVariableList>();
3295 VariableList = Insertion.first->second.get();
3296 } else if (GV->hasComdat())
3297 // Emit this global variable into a COMDAT section.
3298 VariableList = &ComdatVariables;
3299 else
3300 // Emit this global variable in a single global symbol section.
3301 VariableList = &GlobalVariables;
3302 CVGlobalVariable CVGV = {.DIGV: DIGV, .GVInfo: GV};
3303 VariableList->emplace_back(Args: std::move(CVGV));
3304 }
3305 }
3306}
3307
3308void CodeViewDebug::collectDebugInfoForGlobals() {
3309 for (const CVGlobalVariable &CVGV : GlobalVariables) {
3310 const DIGlobalVariable *DIGV = CVGV.DIGV;
3311 const DIScope *Scope = DIGV->getScope();
3312 getCompleteTypeIndex(Ty: DIGV->getType());
3313 getFullyQualifiedName(Scope, Name: DIGV->getName());
3314 }
3315
3316 for (const CVGlobalVariable &CVGV : ComdatVariables) {
3317 const DIGlobalVariable *DIGV = CVGV.DIGV;
3318 const DIScope *Scope = DIGV->getScope();
3319 getCompleteTypeIndex(Ty: DIGV->getType());
3320 getFullyQualifiedName(Scope, Name: DIGV->getName());
3321 }
3322}
3323
3324void CodeViewDebug::emitDebugInfoForGlobals() {
3325 // First, emit all globals that are not in a comdat in a single symbol
3326 // substream. MSVC doesn't like it if the substream is empty, so only open
3327 // it if we have at least one global to emit.
3328 switchToDebugSectionForSymbol(GVSym: nullptr);
3329 if (!GlobalVariables.empty() || !StaticConstMembers.empty()) {
3330 OS.AddComment(T: "Symbol subsection for globals");
3331 MCSymbol *EndLabel = beginCVSubsection(Kind: DebugSubsectionKind::Symbols);
3332 emitGlobalVariableList(Globals: GlobalVariables);
3333 emitStaticConstMemberList();
3334 endCVSubsection(EndLabel);
3335 }
3336
3337 // Second, emit each global that is in a comdat into its own .debug$S
3338 // section along with its own symbol substream.
3339 for (const CVGlobalVariable &CVGV : ComdatVariables) {
3340 const GlobalVariable *GV = cast<const GlobalVariable *>(Val: CVGV.GVInfo);
3341 MCSymbol *GVSym = Asm->getSymbol(GV);
3342 OS.AddComment(T: "Symbol subsection for " +
3343 Twine(GlobalValue::dropLLVMManglingEscape(Name: GV->getName())));
3344 switchToDebugSectionForSymbol(GVSym);
3345 MCSymbol *EndLabel = beginCVSubsection(Kind: DebugSubsectionKind::Symbols);
3346 // FIXME: emitDebugInfoForGlobal() doesn't handle DIExpressions.
3347 emitDebugInfoForGlobal(CVGV);
3348 endCVSubsection(EndLabel);
3349 }
3350}
3351
3352void CodeViewDebug::emitDebugInfoForRetainedTypes() {
3353 NamedMDNode *CUs = MMI->getModule()->getNamedMetadata(Name: "llvm.dbg.cu");
3354 for (const MDNode *Node : CUs->operands()) {
3355 for (auto *Ty : cast<DICompileUnit>(Val: Node)->getRetainedTypes()) {
3356 if (DIType *RT = dyn_cast<DIType>(Val: Ty)) {
3357 getTypeIndex(Ty: RT);
3358 // FIXME: Add to global/local DTU list.
3359 }
3360 }
3361 }
3362}
3363
3364// Emit each global variable in the specified array.
3365void CodeViewDebug::emitGlobalVariableList(ArrayRef<CVGlobalVariable> Globals) {
3366 for (const CVGlobalVariable &CVGV : Globals) {
3367 // FIXME: emitDebugInfoForGlobal() doesn't handle DIExpressions.
3368 emitDebugInfoForGlobal(CVGV);
3369 }
3370}
3371
3372void CodeViewDebug::emitConstantSymbolRecord(const DIType *DTy, APSInt &Value,
3373 const std::string &QualifiedName) {
3374 MCSymbol *SConstantEnd = beginSymbolRecord(SymKind: SymbolKind::S_CONSTANT);
3375 OS.AddComment(T: "Type");
3376 OS.emitInt32(Value: getTypeIndex(Ty: DTy).getIndex());
3377
3378 OS.AddComment(T: "Value");
3379
3380 // Encoded integers shouldn't need more than 10 bytes.
3381 uint8_t Data[10];
3382 BinaryStreamWriter Writer(Data, llvm::endianness::little);
3383 CodeViewRecordIO IO(Writer);
3384 cantFail(Err: IO.mapEncodedInteger(Value));
3385 StringRef SRef((char *)Data, Writer.getOffset());
3386 OS.emitBinaryData(Data: SRef);
3387
3388 OS.AddComment(T: "Name");
3389 emitNullTerminatedSymbolName(OS, S: QualifiedName);
3390 endSymbolRecord(SymEnd: SConstantEnd);
3391}
3392
3393void CodeViewDebug::emitStaticConstMemberList() {
3394 for (const DIDerivedType *DTy : StaticConstMembers) {
3395 const DIScope *Scope = DTy->getScope();
3396
3397 APSInt Value;
3398 if (const ConstantInt *CI =
3399 dyn_cast_or_null<ConstantInt>(Val: DTy->getConstant()))
3400 Value = APSInt(CI->getValue(),
3401 DebugHandlerBase::isUnsignedDIType(Ty: DTy->getBaseType()));
3402 else if (const ConstantFP *CFP =
3403 dyn_cast_or_null<ConstantFP>(Val: DTy->getConstant()))
3404 Value = APSInt(CFP->getValueAPF().bitcastToAPInt(), true);
3405 else
3406 llvm_unreachable("cannot emit a constant without a value");
3407
3408 emitConstantSymbolRecord(DTy: DTy->getBaseType(), Value,
3409 QualifiedName: getFullyQualifiedName(Scope, Name: DTy->getName()));
3410 }
3411}
3412
3413static bool isFloatDIType(const DIType *Ty) {
3414 if (isa<DICompositeType>(Val: Ty))
3415 return false;
3416
3417 if (auto *DTy = dyn_cast<DIDerivedType>(Val: Ty)) {
3418 dwarf::Tag T = (dwarf::Tag)Ty->getTag();
3419 if (T == dwarf::DW_TAG_pointer_type ||
3420 T == dwarf::DW_TAG_ptr_to_member_type ||
3421 T == dwarf::DW_TAG_reference_type ||
3422 T == dwarf::DW_TAG_rvalue_reference_type)
3423 return false;
3424 assert(DTy->getBaseType() && "Expected valid base type");
3425 return isFloatDIType(Ty: DTy->getBaseType());
3426 }
3427
3428 auto *BTy = cast<DIBasicType>(Val: Ty);
3429 return (BTy->getEncoding() == dwarf::DW_ATE_float);
3430}
3431
3432void CodeViewDebug::emitDebugInfoForGlobal(const CVGlobalVariable &CVGV) {
3433 const DIGlobalVariable *DIGV = CVGV.DIGV;
3434
3435 const DIScope *Scope = DIGV->getScope();
3436 // For static data members, get the scope from the declaration.
3437 if (const auto *MemberDecl = dyn_cast_or_null<DIDerivedType>(
3438 Val: DIGV->getRawStaticDataMemberDeclaration()))
3439 Scope = MemberDecl->getScope();
3440 // For static local variables and Fortran, the scoping portion is elided
3441 // in its name so that we can reference the variable in the command line
3442 // of the VS debugger.
3443 std::string QualifiedName =
3444 (moduleIsInFortran() || (Scope && isa<DILocalScope>(Val: Scope)))
3445 ? std::string(DIGV->getName())
3446 : getFullyQualifiedName(Scope, Name: DIGV->getName());
3447
3448 if (const GlobalVariable *GV =
3449 dyn_cast_if_present<const GlobalVariable *>(Val: CVGV.GVInfo)) {
3450 // DataSym record, see SymbolRecord.h for more info. Thread local data
3451 // happens to have the same format as global data.
3452 MCSymbol *GVSym = Asm->getSymbol(GV);
3453 SymbolKind DataSym = GV->isThreadLocal()
3454 ? (DIGV->isLocalToUnit() ? SymbolKind::S_LTHREAD32
3455 : SymbolKind::S_GTHREAD32)
3456 : (DIGV->isLocalToUnit() ? SymbolKind::S_LDATA32
3457 : SymbolKind::S_GDATA32);
3458 MCSymbol *DataEnd = beginSymbolRecord(SymKind: DataSym);
3459 OS.AddComment(T: "Type");
3460 OS.emitInt32(Value: getCompleteTypeIndex(Ty: DIGV->getType()).getIndex());
3461 OS.AddComment(T: "DataOffset");
3462
3463 // Use the offset seen while collecting info on globals.
3464 uint64_t Offset = CVGlobalVariableOffsets.lookup(Val: DIGV);
3465 OS.emitCOFFSecRel32(Symbol: GVSym, Offset);
3466
3467 OS.AddComment(T: "Segment");
3468 OS.emitCOFFSectionIndex(Symbol: GVSym);
3469 OS.AddComment(T: "Name");
3470 const unsigned LengthOfDataRecord = 12;
3471 emitNullTerminatedSymbolName(OS, S: QualifiedName, MaxFixedRecordLength: LengthOfDataRecord);
3472 endSymbolRecord(SymEnd: DataEnd);
3473 } else {
3474 const DIExpression *DIE = cast<const DIExpression *>(Val: CVGV.GVInfo);
3475 assert(DIE->isConstant() &&
3476 "Global constant variables must contain a constant expression.");
3477
3478 // Use unsigned for floats.
3479 bool isUnsigned = isFloatDIType(Ty: DIGV->getType())
3480 ? true
3481 : DebugHandlerBase::isUnsignedDIType(Ty: DIGV->getType());
3482 APSInt Value(APInt(/*BitWidth=*/64, DIE->getElement(I: 1)), isUnsigned);
3483 emitConstantSymbolRecord(DTy: DIGV->getType(), Value, QualifiedName);
3484 }
3485}
3486
3487void forEachJumpTableBranch(
3488 const MachineFunction *MF, bool isThumb,
3489 const std::function<void(const MachineJumpTableInfo &, const MachineInstr &,
3490 int64_t)> &Callback) {
3491 auto JTI = MF->getJumpTableInfo();
3492 if (JTI && !JTI->isEmpty()) {
3493#ifndef NDEBUG
3494 auto UsedJTs = llvm::SmallBitVector(JTI->getJumpTables().size());
3495#endif
3496 for (const auto &MBB : *MF) {
3497 // Search for indirect branches...
3498 const auto LastMI = MBB.getFirstTerminator();
3499 if (LastMI != MBB.end() && LastMI->isIndirectBranch()) {
3500 if (isThumb) {
3501 // ... that directly use jump table operands.
3502 // NOTE: ARM uses pattern matching to lower its BR_JT SDNode to
3503 // machine instructions, hence inserting a JUMP_TABLE_DEBUG_INFO node
3504 // interferes with this process *but* the resulting pseudo-instruction
3505 // uses a Jump Table operand, so extract the jump table index directly
3506 // from that.
3507 for (const auto &MO : LastMI->operands()) {
3508 if (MO.isJTI()) {
3509 unsigned Index = MO.getIndex();
3510#ifndef NDEBUG
3511 UsedJTs.set(Index);
3512#endif
3513 Callback(*JTI, *LastMI, Index);
3514 break;
3515 }
3516 }
3517 } else {
3518 // ... that have jump table debug info.
3519 // NOTE: The debug info is inserted as a JUMP_TABLE_DEBUG_INFO node
3520 // when lowering the BR_JT SDNode to an indirect branch.
3521 for (auto I = MBB.instr_rbegin(), E = MBB.instr_rend(); I != E; ++I) {
3522 if (I->isJumpTableDebugInfo()) {
3523 unsigned Index = I->getOperand(i: 0).getImm();
3524#ifndef NDEBUG
3525 UsedJTs.set(Index);
3526#endif
3527 Callback(*JTI, *LastMI, Index);
3528 break;
3529 }
3530 }
3531 }
3532 }
3533 }
3534#ifndef NDEBUG
3535 assert(UsedJTs.all() &&
3536 "Some of jump tables were not used in a debug info instruction");
3537#endif
3538 }
3539}
3540
3541void CodeViewDebug::discoverJumpTableBranches(const MachineFunction *MF,
3542 bool isThumb) {
3543 forEachJumpTableBranch(
3544 MF, isThumb,
3545 Callback: [this](const MachineJumpTableInfo &, const MachineInstr &BranchMI,
3546 int64_t) { requestLabelBeforeInsn(MI: &BranchMI); });
3547}
3548
3549void CodeViewDebug::collectDebugInfoForJumpTables(const MachineFunction *MF,
3550 bool isThumb) {
3551 forEachJumpTableBranch(
3552 MF, isThumb,
3553 Callback: [this, MF](const MachineJumpTableInfo &JTI, const MachineInstr &BranchMI,
3554 int64_t JumpTableIndex) {
3555 // For label-difference jump tables, find the base expression.
3556 // Otherwise the jump table uses an absolute address (so no base
3557 // is required).
3558 const MCSymbol *Base;
3559 uint64_t BaseOffset = 0;
3560 const MCSymbol *Branch = getLabelBeforeInsn(MI: &BranchMI);
3561 JumpTableEntrySize EntrySize;
3562 switch (JTI.getEntryKind()) {
3563 case MachineJumpTableInfo::EK_Custom32:
3564 case MachineJumpTableInfo::EK_GPRel32BlockAddress:
3565 case MachineJumpTableInfo::EK_GPRel64BlockAddress:
3566 llvm_unreachable(
3567 "EK_Custom32, EK_GPRel32BlockAddress, and "
3568 "EK_GPRel64BlockAddress should never be emitted for COFF");
3569 case MachineJumpTableInfo::EK_BlockAddress:
3570 // Each entry is an absolute address.
3571 EntrySize = JumpTableEntrySize::Pointer;
3572 Base = nullptr;
3573 break;
3574 case MachineJumpTableInfo::EK_Inline:
3575 case MachineJumpTableInfo::EK_LabelDifference32:
3576 case MachineJumpTableInfo::EK_LabelDifference64:
3577 // Ask the AsmPrinter.
3578 std::tie(args&: Base, args&: BaseOffset, args&: Branch, args&: EntrySize) =
3579 Asm->getCodeViewJumpTableInfo(JTI: JumpTableIndex, BranchInstr: &BranchMI, BranchLabel: Branch);
3580 break;
3581 }
3582
3583 const MachineJumpTableEntry &JTE = JTI.getJumpTables()[JumpTableIndex];
3584 JumpTableInfo CVJTI{.EntrySize: EntrySize,
3585 .Base: Base,
3586 .BaseOffset: BaseOffset,
3587 .Branch: Branch,
3588 .Table: MF->getJTISymbol(JTI: JumpTableIndex, Ctx&: MMI->getContext()),
3589 .TableSize: JTE.MBBs.size(),
3590 .Cases: {}};
3591 for (const auto &MBB : JTE.MBBs)
3592 CVJTI.Cases.push_back(x: MBB->getSymbol());
3593 CurFn->JumpTables.push_back(x: std::move(CVJTI));
3594 });
3595}
3596
3597void CodeViewDebug::emitDebugInfoForJumpTables(const FunctionInfo &FI) {
3598 // Emit S_LABEL32 records for each jump target
3599 for (const auto &JumpTable : FI.JumpTables) {
3600 for (const auto &CaseSym : JumpTable.Cases) {
3601 MCSymbol *LabelEnd = beginSymbolRecord(SymKind: SymbolKind::S_LABEL32);
3602 OS.AddComment(T: "Offset and segment");
3603 OS.emitCOFFSecRel32(Symbol: CaseSym, Offset: 0);
3604 OS.AddComment(T: "Flags");
3605 OS.emitInt8(Value: 0);
3606 emitNullTerminatedSymbolName(OS, S: CaseSym->getName());
3607 endSymbolRecord(SymEnd: LabelEnd);
3608 }
3609 }
3610
3611 for (const auto &JumpTable : FI.JumpTables) {
3612 MCSymbol *JumpTableEnd = beginSymbolRecord(SymKind: SymbolKind::S_ARMSWITCHTABLE);
3613 if (JumpTable.Base) {
3614 OS.AddComment(T: "Base offset");
3615 OS.emitCOFFSecRel32(Symbol: JumpTable.Base, Offset: JumpTable.BaseOffset);
3616 OS.AddComment(T: "Base section index");
3617 OS.emitCOFFSectionIndex(Symbol: JumpTable.Base);
3618 } else {
3619 OS.AddComment(T: "Base offset");
3620 OS.emitInt32(Value: 0);
3621 OS.AddComment(T: "Base section index");
3622 OS.emitInt16(Value: 0);
3623 }
3624 OS.AddComment(T: "Switch type");
3625 OS.emitInt16(Value: static_cast<uint16_t>(JumpTable.EntrySize));
3626 OS.AddComment(T: "Branch offset");
3627 OS.emitCOFFSecRel32(Symbol: JumpTable.Branch, /*Offset=*/0);
3628 OS.AddComment(T: "Table offset");
3629 OS.emitCOFFSecRel32(Symbol: JumpTable.Table, /*Offset=*/0);
3630 OS.AddComment(T: "Branch section index");
3631 OS.emitCOFFSectionIndex(Symbol: JumpTable.Branch);
3632 OS.AddComment(T: "Table section index");
3633 OS.emitCOFFSectionIndex(Symbol: JumpTable.Table);
3634 OS.AddComment(T: "Entries count");
3635 OS.emitInt32(Value: JumpTable.TableSize);
3636 endSymbolRecord(SymEnd: JumpTableEnd);
3637 }
3638}
3639
3640void CodeViewDebug::emitInlinees(
3641 const SmallSet<codeview::TypeIndex, 1> &Inlinees) {
3642 // Divide the list of inlinees into chunks such that each chunk fits within
3643 // one record.
3644 constexpr size_t ChunkSize =
3645 (MaxRecordLength - sizeof(SymbolKind) - sizeof(uint32_t)) /
3646 sizeof(uint32_t);
3647
3648 SmallVector<TypeIndex> SortedInlinees{Inlinees.begin(), Inlinees.end()};
3649 llvm::sort(C&: SortedInlinees);
3650
3651 size_t CurrentIndex = 0;
3652 while (CurrentIndex < SortedInlinees.size()) {
3653 auto Symbol = beginSymbolRecord(SymKind: SymbolKind::S_INLINEES);
3654 auto CurrentChunkSize =
3655 std::min(a: ChunkSize, b: SortedInlinees.size() - CurrentIndex);
3656 OS.AddComment(T: "Count");
3657 OS.emitInt32(Value: CurrentChunkSize);
3658
3659 const size_t CurrentChunkEnd = CurrentIndex + CurrentChunkSize;
3660 for (; CurrentIndex < CurrentChunkEnd; ++CurrentIndex) {
3661 OS.AddComment(T: "Inlinee");
3662 OS.emitInt32(Value: SortedInlinees[CurrentIndex].getIndex());
3663 }
3664 endSymbolRecord(SymEnd: Symbol);
3665 }
3666}
3667