1 //===- llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h --------------*- C++ -*-===// 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 #ifndef LLVM_LIB_CODEGEN_ASMPRINTER_CODEVIEWDEBUG_H 14 #define LLVM_LIB_CODEGEN_ASMPRINTER_CODEVIEWDEBUG_H 15 16 #include "llvm/ADT/APSInt.h" 17 #include "llvm/ADT/ArrayRef.h" 18 #include "llvm/ADT/DenseMap.h" 19 #include "llvm/ADT/DenseSet.h" 20 #include "llvm/ADT/MapVector.h" 21 #include "llvm/ADT/PointerUnion.h" 22 #include "llvm/ADT/SetVector.h" 23 #include "llvm/ADT/SmallSet.h" 24 #include "llvm/ADT/SmallVector.h" 25 #include "llvm/CodeGen/DbgEntityHistoryCalculator.h" 26 #include "llvm/CodeGen/DebugHandlerBase.h" 27 #include "llvm/CodeGen/MachineJumpTableInfo.h" 28 #include "llvm/DebugInfo/CodeView/CodeView.h" 29 #include "llvm/DebugInfo/CodeView/GlobalTypeTableBuilder.h" 30 #include "llvm/DebugInfo/CodeView/TypeIndex.h" 31 #include "llvm/IR/DebugLoc.h" 32 #include "llvm/Support/Allocator.h" 33 #include "llvm/Support/Compiler.h" 34 #include <cstdint> 35 #include <map> 36 #include <string> 37 #include <tuple> 38 #include <unordered_map> 39 #include <utility> 40 #include <vector> 41 42 namespace llvm { 43 44 struct ClassInfo; 45 class StringRef; 46 class AsmPrinter; 47 class Function; 48 class GlobalVariable; 49 class MCSectionCOFF; 50 class MCStreamer; 51 class MCSymbol; 52 class MachineFunction; 53 54 /// Collects and handles line tables information in a CodeView format. 55 class LLVM_LIBRARY_VISIBILITY CodeViewDebug : public DebugHandlerBase { 56 public: 57 struct LocalVarDef { 58 /// Indicates that variable data is stored in memory relative to the 59 /// specified register. 60 int InMemory : 1; 61 62 /// Offset of variable data in memory. 63 int DataOffset : 31; 64 65 /// Non-zero if this is a piece of an aggregate. 66 uint16_t IsSubfield : 1; 67 68 /// Offset into aggregate. 69 uint16_t StructOffset : 15; 70 71 /// Register containing the data or the register base of the memory 72 /// location containing the data. 73 uint16_t CVRegister; 74 toOpaqueValueLocalVarDef75 uint64_t static toOpaqueValue(const LocalVarDef DR) { 76 uint64_t Val = 0; 77 std::memcpy(&Val, &DR, sizeof(Val)); 78 return Val; 79 } 80 createFromOpaqueValueLocalVarDef81 LocalVarDef static createFromOpaqueValue(uint64_t Val) { 82 LocalVarDef DR; 83 std::memcpy(&DR, &Val, sizeof(Val)); 84 return DR; 85 } 86 }; 87 88 static_assert(sizeof(uint64_t) == sizeof(LocalVarDef)); 89 90 private: 91 MCStreamer &OS; 92 BumpPtrAllocator Allocator; 93 codeview::GlobalTypeTableBuilder TypeTable; 94 95 /// Whether to emit type record hashes into .debug$H. 96 bool EmitDebugGlobalHashes = false; 97 98 /// The codeview CPU type used by the translation unit. 99 codeview::CPUType TheCPU; 100 101 static LocalVarDef createDefRangeMem(uint16_t CVRegister, int Offset); 102 103 /// Similar to DbgVariable in DwarfDebug, but not dwarf-specific. 104 struct LocalVariable { 105 const DILocalVariable *DIVar = nullptr; 106 MapVector<LocalVarDef, 107 SmallVector<std::pair<const MCSymbol *, const MCSymbol *>, 1>> 108 DefRanges; 109 bool UseReferenceType = false; 110 std::optional<APSInt> ConstantValue; 111 }; 112 113 struct CVGlobalVariable { 114 const DIGlobalVariable *DIGV; 115 PointerUnion<const GlobalVariable *, const DIExpression *> GVInfo; 116 }; 117 118 struct InlineSite { 119 SmallVector<LocalVariable, 1> InlinedLocals; 120 SmallVector<const DILocation *, 1> ChildSites; 121 const DISubprogram *Inlinee = nullptr; 122 123 /// The ID of the inline site or function used with .cv_loc. Not a type 124 /// index. 125 unsigned SiteFuncId = 0; 126 }; 127 128 // Combines information from DILexicalBlock and LexicalScope. 129 struct LexicalBlock { 130 SmallVector<LocalVariable, 1> Locals; 131 SmallVector<CVGlobalVariable, 1> Globals; 132 SmallVector<LexicalBlock *, 1> Children; 133 const MCSymbol *Begin; 134 const MCSymbol *End; 135 StringRef Name; 136 }; 137 138 struct JumpTableInfo { 139 codeview::JumpTableEntrySize EntrySize; 140 const MCSymbol *Base; 141 uint64_t BaseOffset; 142 const MCSymbol *Branch; 143 const MCSymbol *Table; 144 size_t TableSize; 145 }; 146 147 // For each function, store a vector of labels to its instructions, as well as 148 // to the end of the function. 149 struct FunctionInfo { 150 FunctionInfo() = default; 151 152 // Uncopyable. 153 FunctionInfo(const FunctionInfo &FI) = delete; 154 155 /// Map from inlined call site to inlined instructions and child inlined 156 /// call sites. Listed in program order. 157 std::unordered_map<const DILocation *, InlineSite> InlineSites; 158 159 /// Ordered list of top-level inlined call sites. 160 SmallVector<const DILocation *, 1> ChildSites; 161 162 /// Set of all functions directly inlined into this one. 163 SmallSet<codeview::TypeIndex, 1> Inlinees; 164 165 SmallVector<LocalVariable, 1> Locals; 166 SmallVector<CVGlobalVariable, 1> Globals; 167 168 std::unordered_map<const DILexicalBlockBase*, LexicalBlock> LexicalBlocks; 169 170 // Lexical blocks containing local variables. 171 SmallVector<LexicalBlock *, 1> ChildBlocks; 172 173 std::vector<std::pair<MCSymbol *, MDNode *>> Annotations; 174 std::vector<std::tuple<const MCSymbol *, const MCSymbol *, const DIType *>> 175 HeapAllocSites; 176 177 std::vector<JumpTableInfo> JumpTables; 178 179 const MCSymbol *Begin = nullptr; 180 const MCSymbol *End = nullptr; 181 unsigned FuncId = 0; 182 unsigned LastFileId = 0; 183 184 /// Number of bytes allocated in the prologue for all local stack objects. 185 unsigned FrameSize = 0; 186 187 /// Number of bytes of parameters on the stack. 188 unsigned ParamSize = 0; 189 190 /// Number of bytes pushed to save CSRs. 191 unsigned CSRSize = 0; 192 193 /// Adjustment to apply on x86 when using the VFRAME frame pointer. 194 int OffsetAdjustment = 0; 195 196 /// Two-bit value indicating which register is the designated frame pointer 197 /// register for local variables. Included in S_FRAMEPROC. 198 codeview::EncodedFramePtrReg EncodedLocalFramePtrReg = 199 codeview::EncodedFramePtrReg::None; 200 201 /// Two-bit value indicating which register is the designated frame pointer 202 /// register for stack parameters. Included in S_FRAMEPROC. 203 codeview::EncodedFramePtrReg EncodedParamFramePtrReg = 204 codeview::EncodedFramePtrReg::None; 205 206 codeview::FrameProcedureOptions FrameProcOpts; 207 208 bool HasStackRealignment = false; 209 210 bool HaveLineInfo = false; 211 212 bool HasFramePointer = false; 213 }; 214 FunctionInfo *CurFn = nullptr; 215 216 codeview::SourceLanguage CurrentSourceLanguage = 217 codeview::SourceLanguage::Masm; 218 219 // This map records the constant offset in DIExpression of the 220 // DIGlobalVariableExpression referencing the DIGlobalVariable. 221 DenseMap<const DIGlobalVariable *, uint64_t> CVGlobalVariableOffsets; 222 223 // Map used to separate variables according to the lexical scope they belong 224 // in. This is populated by recordLocalVariable() before 225 // collectLexicalBlocks() separates the variables between the FunctionInfo 226 // and LexicalBlocks. 227 DenseMap<const LexicalScope *, SmallVector<LocalVariable, 1>> ScopeVariables; 228 229 // Map to separate global variables according to the lexical scope they 230 // belong in. A null local scope represents the global scope. 231 typedef SmallVector<CVGlobalVariable, 1> GlobalVariableList; 232 DenseMap<const DIScope*, std::unique_ptr<GlobalVariableList> > ScopeGlobals; 233 234 // Array of global variables which need to be emitted into a COMDAT section. 235 SmallVector<CVGlobalVariable, 1> ComdatVariables; 236 237 // Array of non-COMDAT global variables. 238 SmallVector<CVGlobalVariable, 1> GlobalVariables; 239 240 /// List of static const data members to be emitted as S_CONSTANTs. 241 SmallVector<const DIDerivedType *, 4> StaticConstMembers; 242 243 /// The set of comdat .debug$S sections that we've seen so far. Each section 244 /// must start with a magic version number that must only be emitted once. 245 /// This set tracks which sections we've already opened. 246 DenseSet<MCSectionCOFF *> ComdatDebugSections; 247 248 /// Switch to the appropriate .debug$S section for GVSym. If GVSym, the symbol 249 /// of an emitted global value, is in a comdat COFF section, this will switch 250 /// to a new .debug$S section in that comdat. This method ensures that the 251 /// section starts with the magic version number on first use. If GVSym is 252 /// null, uses the main .debug$S section. 253 void switchToDebugSectionForSymbol(const MCSymbol *GVSym); 254 255 /// The next available function index for use with our .cv_* directives. Not 256 /// to be confused with type indices for LF_FUNC_ID records. 257 unsigned NextFuncId = 0; 258 259 InlineSite &getInlineSite(const DILocation *InlinedAt, 260 const DISubprogram *Inlinee); 261 262 codeview::TypeIndex getFuncIdForSubprogram(const DISubprogram *SP); 263 264 void calculateRanges(LocalVariable &Var, 265 const DbgValueHistoryMap::Entries &Entries); 266 267 /// Remember some debug info about each function. Keep it in a stable order to 268 /// emit at the end of the TU. 269 MapVector<const Function *, std::unique_ptr<FunctionInfo>> FnDebugInfo; 270 271 /// Map from full file path to .cv_file id. Full paths are built from DIFiles 272 /// and are stored in FileToFilepathMap; 273 DenseMap<StringRef, unsigned> FileIdMap; 274 275 /// All inlined subprograms in the order they should be emitted. 276 SmallSetVector<const DISubprogram *, 4> InlinedSubprograms; 277 278 /// Map from a pair of DI metadata nodes and its DI type (or scope) that can 279 /// be nullptr, to CodeView type indices. Primarily indexed by 280 /// {DIType*, DIType*} and {DISubprogram*, DIType*}. 281 /// 282 /// The second entry in the key is needed for methods as DISubroutineType 283 /// representing static method type are shared with non-method function type. 284 DenseMap<std::pair<const DINode *, const DIType *>, codeview::TypeIndex> 285 TypeIndices; 286 287 /// Map from DICompositeType* to complete type index. Non-record types are 288 /// always looked up in the normal TypeIndices map. 289 DenseMap<const DICompositeType *, codeview::TypeIndex> CompleteTypeIndices; 290 291 /// Complete record types to emit after all active type lowerings are 292 /// finished. 293 SmallVector<const DICompositeType *, 4> DeferredCompleteTypes; 294 295 /// Number of type lowering frames active on the stack. 296 unsigned TypeEmissionLevel = 0; 297 298 codeview::TypeIndex VBPType; 299 300 const DISubprogram *CurrentSubprogram = nullptr; 301 302 // The UDTs we have seen while processing types; each entry is a pair of type 303 // index and type name. 304 std::vector<std::pair<std::string, const DIType *>> LocalUDTs; 305 std::vector<std::pair<std::string, const DIType *>> GlobalUDTs; 306 307 using FileToFilepathMapTy = std::map<const DIFile *, std::string>; 308 FileToFilepathMapTy FileToFilepathMap; 309 310 StringRef getFullFilepath(const DIFile *File); 311 312 unsigned maybeRecordFile(const DIFile *F); 313 314 void maybeRecordLocation(const DebugLoc &DL, const MachineFunction *MF); 315 316 void clear(); 317 setCurrentSubprogram(const DISubprogram * SP)318 void setCurrentSubprogram(const DISubprogram *SP) { 319 CurrentSubprogram = SP; 320 LocalUDTs.clear(); 321 } 322 323 /// Emit the magic version number at the start of a CodeView type or symbol 324 /// section. Appears at the front of every .debug$S or .debug$T or .debug$P 325 /// section. 326 void emitCodeViewMagicVersion(); 327 328 void emitTypeInformation(); 329 330 void emitTypeGlobalHashes(); 331 332 void emitObjName(); 333 334 void emitCompilerInformation(); 335 336 void emitBuildInfo(); 337 338 void emitInlineeLinesSubsection(); 339 340 void emitDebugInfoForThunk(const Function *GV, 341 FunctionInfo &FI, 342 const MCSymbol *Fn); 343 344 void emitDebugInfoForFunction(const Function *GV, FunctionInfo &FI); 345 346 void emitDebugInfoForRetainedTypes(); 347 348 void emitDebugInfoForUDTs( 349 const std::vector<std::pair<std::string, const DIType *>> &UDTs); 350 351 void collectDebugInfoForGlobals(); 352 void emitDebugInfoForGlobals(); 353 void emitGlobalVariableList(ArrayRef<CVGlobalVariable> Globals); 354 void emitConstantSymbolRecord(const DIType *DTy, APSInt &Value, 355 const std::string &QualifiedName); 356 void emitDebugInfoForGlobal(const CVGlobalVariable &CVGV); 357 void emitStaticConstMemberList(); 358 359 /// Opens a subsection of the given kind in a .debug$S codeview section. 360 /// Returns an end label for use with endCVSubsection when the subsection is 361 /// finished. 362 MCSymbol *beginCVSubsection(codeview::DebugSubsectionKind Kind); 363 void endCVSubsection(MCSymbol *EndLabel); 364 365 /// Opens a symbol record of the given kind. Returns an end label for use with 366 /// endSymbolRecord. 367 MCSymbol *beginSymbolRecord(codeview::SymbolKind Kind); 368 void endSymbolRecord(MCSymbol *SymEnd); 369 370 /// Emits an S_END, S_INLINESITE_END, or S_PROC_ID_END record. These records 371 /// are empty, so we emit them with a simpler assembly sequence that doesn't 372 /// involve labels. 373 void emitEndSymbolRecord(codeview::SymbolKind EndKind); 374 375 void emitInlinedCallSite(const FunctionInfo &FI, const DILocation *InlinedAt, 376 const InlineSite &Site); 377 378 void emitInlinees(const SmallSet<codeview::TypeIndex, 1> &Inlinees); 379 380 using InlinedEntity = DbgValueHistoryMap::InlinedEntity; 381 382 void collectGlobalVariableInfo(); 383 void collectVariableInfo(const DISubprogram *SP); 384 385 void collectVariableInfoFromMFTable(DenseSet<InlinedEntity> &Processed); 386 387 // Construct the lexical block tree for a routine, pruning emptpy lexical 388 // scopes, and populate it with local variables. 389 void collectLexicalBlockInfo(SmallVectorImpl<LexicalScope *> &Scopes, 390 SmallVectorImpl<LexicalBlock *> &Blocks, 391 SmallVectorImpl<LocalVariable> &Locals, 392 SmallVectorImpl<CVGlobalVariable> &Globals); 393 void collectLexicalBlockInfo(LexicalScope &Scope, 394 SmallVectorImpl<LexicalBlock *> &ParentBlocks, 395 SmallVectorImpl<LocalVariable> &ParentLocals, 396 SmallVectorImpl<CVGlobalVariable> &ParentGlobals); 397 398 /// Records information about a local variable in the appropriate scope. In 399 /// particular, locals from inlined code live inside the inlining site. 400 void recordLocalVariable(LocalVariable &&Var, const LexicalScope *LS); 401 402 /// Emits local variables in the appropriate order. 403 void emitLocalVariableList(const FunctionInfo &FI, 404 ArrayRef<LocalVariable> Locals); 405 406 /// Emits an S_LOCAL record and its associated defined ranges. 407 void emitLocalVariable(const FunctionInfo &FI, const LocalVariable &Var); 408 409 /// Emits a sequence of lexical block scopes and their children. 410 void emitLexicalBlockList(ArrayRef<LexicalBlock *> Blocks, 411 const FunctionInfo& FI); 412 413 /// Emit a lexical block scope and its children. 414 void emitLexicalBlock(const LexicalBlock &Block, const FunctionInfo& FI); 415 416 /// Translates the DIType to codeview if necessary and returns a type index 417 /// for it. 418 codeview::TypeIndex getTypeIndex(const DIType *Ty, 419 const DIType *ClassTy = nullptr); 420 421 codeview::TypeIndex 422 getTypeIndexForThisPtr(const DIDerivedType *PtrTy, 423 const DISubroutineType *SubroutineTy); 424 425 codeview::TypeIndex getTypeIndexForReferenceTo(const DIType *Ty); 426 427 codeview::TypeIndex getMemberFunctionType(const DISubprogram *SP, 428 const DICompositeType *Class); 429 430 codeview::TypeIndex getScopeIndex(const DIScope *Scope); 431 432 codeview::TypeIndex getVBPTypeIndex(); 433 434 void addToUDTs(const DIType *Ty); 435 436 void addUDTSrcLine(const DIType *Ty, codeview::TypeIndex TI); 437 438 codeview::TypeIndex lowerType(const DIType *Ty, const DIType *ClassTy); 439 codeview::TypeIndex lowerTypeAlias(const DIDerivedType *Ty); 440 codeview::TypeIndex lowerTypeArray(const DICompositeType *Ty); 441 codeview::TypeIndex lowerTypeString(const DIStringType *Ty); 442 codeview::TypeIndex lowerTypeBasic(const DIBasicType *Ty); 443 codeview::TypeIndex lowerTypePointer( 444 const DIDerivedType *Ty, 445 codeview::PointerOptions PO = codeview::PointerOptions::None); 446 codeview::TypeIndex lowerTypeMemberPointer( 447 const DIDerivedType *Ty, 448 codeview::PointerOptions PO = codeview::PointerOptions::None); 449 codeview::TypeIndex lowerTypeModifier(const DIDerivedType *Ty); 450 codeview::TypeIndex lowerTypeFunction(const DISubroutineType *Ty); 451 codeview::TypeIndex lowerTypeVFTableShape(const DIDerivedType *Ty); 452 codeview::TypeIndex lowerTypeMemberFunction( 453 const DISubroutineType *Ty, const DIType *ClassTy, int ThisAdjustment, 454 bool IsStaticMethod, 455 codeview::FunctionOptions FO = codeview::FunctionOptions::None); 456 codeview::TypeIndex lowerTypeEnum(const DICompositeType *Ty); 457 codeview::TypeIndex lowerTypeClass(const DICompositeType *Ty); 458 codeview::TypeIndex lowerTypeUnion(const DICompositeType *Ty); 459 460 /// Symbol records should point to complete types, but type records should 461 /// always point to incomplete types to avoid cycles in the type graph. Only 462 /// use this entry point when generating symbol records. The complete and 463 /// incomplete type indices only differ for record types. All other types use 464 /// the same index. 465 codeview::TypeIndex getCompleteTypeIndex(const DIType *Ty); 466 467 codeview::TypeIndex lowerCompleteTypeClass(const DICompositeType *Ty); 468 codeview::TypeIndex lowerCompleteTypeUnion(const DICompositeType *Ty); 469 470 struct TypeLoweringScope; 471 472 void emitDeferredCompleteTypes(); 473 474 void collectMemberInfo(ClassInfo &Info, const DIDerivedType *DDTy); 475 ClassInfo collectClassInfo(const DICompositeType *Ty); 476 477 /// Common record member lowering functionality for record types, which are 478 /// structs, classes, and unions. Returns the field list index and the member 479 /// count. 480 std::tuple<codeview::TypeIndex, codeview::TypeIndex, unsigned, bool> 481 lowerRecordFieldList(const DICompositeType *Ty); 482 483 /// Inserts {{Node, ClassTy}, TI} into TypeIndices and checks for duplicates. 484 codeview::TypeIndex recordTypeIndexForDINode(const DINode *Node, 485 codeview::TypeIndex TI, 486 const DIType *ClassTy = nullptr); 487 488 /// Collect the names of parent scopes, innermost to outermost. Return the 489 /// innermost subprogram scope if present. Ensure that parent type scopes are 490 /// inserted into the type table. 491 const DISubprogram * 492 collectParentScopeNames(const DIScope *Scope, 493 SmallVectorImpl<StringRef> &ParentScopeNames); 494 std::string getFullyQualifiedName(const DIScope *Scope, StringRef Name); 495 std::string getFullyQualifiedName(const DIScope *Scope); 496 497 unsigned getPointerSizeInBytes(); 498 499 void discoverJumpTableBranches(const MachineFunction *MF, bool isThumb); 500 void collectDebugInfoForJumpTables(const MachineFunction *MF, bool isThumb); 501 void emitDebugInfoForJumpTables(const FunctionInfo &FI); 502 503 protected: 504 /// Gather pre-function debug information. 505 void beginFunctionImpl(const MachineFunction *MF) override; 506 507 /// Gather post-function debug information. 508 void endFunctionImpl(const MachineFunction *) override; 509 510 /// Check if the current module is in Fortran. moduleIsInFortran()511 bool moduleIsInFortran() { 512 return CurrentSourceLanguage == codeview::SourceLanguage::Fortran; 513 } 514 515 public: 516 CodeViewDebug(AsmPrinter *AP); 517 518 void beginModule(Module *M) override; 519 520 /// Emit the COFF section that holds the line table information. 521 void endModule() override; 522 523 /// Process beginning of an instruction. 524 void beginInstruction(const MachineInstr *MI) override; 525 }; 526 527 template <> struct DenseMapInfo<CodeViewDebug::LocalVarDef> { 528 529 static inline CodeViewDebug::LocalVarDef getEmptyKey() { 530 return CodeViewDebug::LocalVarDef::createFromOpaqueValue(~0ULL); 531 } 532 533 static inline CodeViewDebug::LocalVarDef getTombstoneKey() { 534 return CodeViewDebug::LocalVarDef::createFromOpaqueValue(~0ULL - 1ULL); 535 } 536 537 static unsigned getHashValue(const CodeViewDebug::LocalVarDef &DR) { 538 return CodeViewDebug::LocalVarDef::toOpaqueValue(DR) * 37ULL; 539 } 540 541 static bool isEqual(const CodeViewDebug::LocalVarDef &LHS, 542 const CodeViewDebug::LocalVarDef &RHS) { 543 return CodeViewDebug::LocalVarDef::toOpaqueValue(LHS) == 544 CodeViewDebug::LocalVarDef::toOpaqueValue(RHS); 545 } 546 }; 547 548 } // end namespace llvm 549 550 #endif // LLVM_LIB_CODEGEN_ASMPRINTER_CODEVIEWDEBUG_H 551