1 //===-- llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.h ----*- C++ -*--===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file contains support for writing Microsoft CodeView debug info. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #ifndef LLVM_LIB_CODEGEN_ASMPRINTER_CODEVIEWDEBUG_H 15 #define LLVM_LIB_CODEGEN_ASMPRINTER_CODEVIEWDEBUG_H 16 17 #include "DebugHandlerBase.h" 18 #include "llvm/ADT/DenseMap.h" 19 #include "llvm/ADT/StringMap.h" 20 #include "llvm/CodeGen/AsmPrinter.h" 21 #include "llvm/CodeGen/MachineFunction.h" 22 #include "llvm/CodeGen/MachineModuleInfo.h" 23 #include "llvm/DebugInfo/CodeView/MemoryTypeTableBuilder.h" 24 #include "llvm/DebugInfo/CodeView/TypeIndex.h" 25 #include "llvm/IR/DebugInfo.h" 26 #include "llvm/IR/DebugLoc.h" 27 #include "llvm/MC/MCStreamer.h" 28 #include "llvm/Target/TargetLoweringObjectFile.h" 29 30 namespace llvm { 31 32 class StringRef; 33 class LexicalScope; 34 struct ClassInfo; 35 36 /// \brief Collects and handles line tables information in a CodeView format. 37 class LLVM_LIBRARY_VISIBILITY CodeViewDebug : public DebugHandlerBase { 38 MCStreamer &OS; 39 codeview::MemoryTypeTableBuilder TypeTable; 40 41 /// Represents the most general definition range. 42 struct LocalVarDefRange { 43 /// Indicates that variable data is stored in memory relative to the 44 /// specified register. 45 int InMemory : 1; 46 47 /// Offset of variable data in memory. 48 int DataOffset : 31; 49 50 /// Offset of the data into the user level struct. If zero, no splitting 51 /// occurred. 52 uint16_t StructOffset; 53 54 /// Register containing the data or the register base of the memory 55 /// location containing the data. 56 uint16_t CVRegister; 57 58 /// Compares all location fields. This includes all fields except the label 59 /// ranges. isDifferentLocationLocalVarDefRange60 bool isDifferentLocation(LocalVarDefRange &O) { 61 return InMemory != O.InMemory || DataOffset != O.DataOffset || 62 StructOffset != O.StructOffset || CVRegister != O.CVRegister; 63 } 64 65 SmallVector<std::pair<const MCSymbol *, const MCSymbol *>, 1> Ranges; 66 }; 67 68 static LocalVarDefRange createDefRangeMem(uint16_t CVRegister, int Offset); 69 static LocalVarDefRange createDefRangeReg(uint16_t CVRegister); 70 71 /// Similar to DbgVariable in DwarfDebug, but not dwarf-specific. 72 struct LocalVariable { 73 const DILocalVariable *DIVar = nullptr; 74 SmallVector<LocalVarDefRange, 1> DefRanges; 75 }; 76 77 struct InlineSite { 78 SmallVector<LocalVariable, 1> InlinedLocals; 79 SmallVector<const DILocation *, 1> ChildSites; 80 const DISubprogram *Inlinee = nullptr; 81 unsigned SiteFuncId = 0; 82 }; 83 84 // For each function, store a vector of labels to its instructions, as well as 85 // to the end of the function. 86 struct FunctionInfo { 87 /// Map from inlined call site to inlined instructions and child inlined 88 /// call sites. Listed in program order. 89 std::unordered_map<const DILocation *, InlineSite> InlineSites; 90 91 /// Ordered list of top-level inlined call sites. 92 SmallVector<const DILocation *, 1> ChildSites; 93 94 SmallVector<LocalVariable, 1> Locals; 95 96 DebugLoc LastLoc; 97 const MCSymbol *Begin = nullptr; 98 const MCSymbol *End = nullptr; 99 unsigned FuncId = 0; 100 unsigned LastFileId = 0; 101 bool HaveLineInfo = false; 102 }; 103 FunctionInfo *CurFn; 104 105 /// The set of comdat .debug$S sections that we've seen so far. Each section 106 /// must start with a magic version number that must only be emitted once. 107 /// This set tracks which sections we've already opened. 108 DenseSet<MCSectionCOFF *> ComdatDebugSections; 109 110 /// Switch to the appropriate .debug$S section for GVSym. If GVSym, the symbol 111 /// of an emitted global value, is in a comdat COFF section, this will switch 112 /// to a new .debug$S section in that comdat. This method ensures that the 113 /// section starts with the magic version number on first use. If GVSym is 114 /// null, uses the main .debug$S section. 115 void switchToDebugSectionForSymbol(const MCSymbol *GVSym); 116 117 /// The next available function index for use with our .cv_* directives. Not 118 /// to be confused with type indices for LF_FUNC_ID records. 119 unsigned NextFuncId = 0; 120 121 InlineSite &getInlineSite(const DILocation *InlinedAt, 122 const DISubprogram *Inlinee); 123 124 codeview::TypeIndex getFuncIdForSubprogram(const DISubprogram *SP); 125 126 static void collectInlineSiteChildren(SmallVectorImpl<unsigned> &Children, 127 const FunctionInfo &FI, 128 const InlineSite &Site); 129 130 /// Remember some debug info about each function. Keep it in a stable order to 131 /// emit at the end of the TU. 132 MapVector<const Function *, FunctionInfo> FnDebugInfo; 133 134 /// Map from DIFile to .cv_file id. 135 DenseMap<const DIFile *, unsigned> FileIdMap; 136 137 /// All inlined subprograms in the order they should be emitted. 138 SmallSetVector<const DISubprogram *, 4> InlinedSubprograms; 139 140 /// Map from a pair of DI metadata nodes and its DI type (or scope) that can 141 /// be nullptr, to CodeView type indices. Primarily indexed by 142 /// {DIType*, DIType*} and {DISubprogram*, DIType*}. 143 /// 144 /// The second entry in the key is needed for methods as DISubroutineType 145 /// representing static method type are shared with non-method function type. 146 DenseMap<std::pair<const DINode *, const DIType *>, codeview::TypeIndex> 147 TypeIndices; 148 149 /// Map from DICompositeType* to complete type index. Non-record types are 150 /// always looked up in the normal TypeIndices map. 151 DenseMap<const DICompositeType *, codeview::TypeIndex> CompleteTypeIndices; 152 153 /// Complete record types to emit after all active type lowerings are 154 /// finished. 155 SmallVector<const DICompositeType *, 4> DeferredCompleteTypes; 156 157 /// Number of type lowering frames active on the stack. 158 unsigned TypeEmissionLevel = 0; 159 160 codeview::TypeIndex VBPType; 161 162 const DISubprogram *CurrentSubprogram = nullptr; 163 164 // The UDTs we have seen while processing types; each entry is a pair of type 165 // index and type name. 166 std::vector<std::pair<std::string, codeview::TypeIndex>> LocalUDTs, 167 GlobalUDTs; 168 169 typedef std::map<const DIFile *, std::string> FileToFilepathMapTy; 170 FileToFilepathMapTy FileToFilepathMap; 171 StringRef getFullFilepath(const DIFile *S); 172 173 unsigned maybeRecordFile(const DIFile *F); 174 175 void maybeRecordLocation(const DebugLoc &DL, const MachineFunction *MF); 176 177 void clear(); 178 setCurrentSubprogram(const DISubprogram * SP)179 void setCurrentSubprogram(const DISubprogram *SP) { 180 CurrentSubprogram = SP; 181 LocalUDTs.clear(); 182 } 183 184 /// Emit the magic version number at the start of a CodeView type or symbol 185 /// section. Appears at the front of every .debug$S or .debug$T section. 186 void emitCodeViewMagicVersion(); 187 188 void emitTypeInformation(); 189 190 void emitInlineeLinesSubsection(); 191 192 void emitDebugInfoForFunction(const Function *GV, FunctionInfo &FI); 193 194 void emitDebugInfoForGlobals(); 195 196 void emitDebugInfoForRetainedTypes(); 197 198 void emitDebugInfoForUDTs( 199 ArrayRef<std::pair<std::string, codeview::TypeIndex>> UDTs); 200 201 void emitDebugInfoForGlobal(const DIGlobalVariable *DIGV, MCSymbol *GVSym); 202 203 /// Opens a subsection of the given kind in a .debug$S codeview section. 204 /// Returns an end label for use with endCVSubsection when the subsection is 205 /// finished. 206 MCSymbol *beginCVSubsection(codeview::ModuleSubstreamKind Kind); 207 208 void endCVSubsection(MCSymbol *EndLabel); 209 210 void emitInlinedCallSite(const FunctionInfo &FI, const DILocation *InlinedAt, 211 const InlineSite &Site); 212 213 typedef DbgValueHistoryMap::InlinedVariable InlinedVariable; 214 215 void collectVariableInfo(const DISubprogram *SP); 216 217 void collectVariableInfoFromMMITable(DenseSet<InlinedVariable> &Processed); 218 219 /// Records information about a local variable in the appropriate scope. In 220 /// particular, locals from inlined code live inside the inlining site. 221 void recordLocalVariable(LocalVariable &&Var, const DILocation *Loc); 222 223 /// Emits local variables in the appropriate order. 224 void emitLocalVariableList(ArrayRef<LocalVariable> Locals); 225 226 /// Emits an S_LOCAL record and its associated defined ranges. 227 void emitLocalVariable(const LocalVariable &Var); 228 229 /// Translates the DIType to codeview if necessary and returns a type index 230 /// for it. 231 codeview::TypeIndex getTypeIndex(DITypeRef TypeRef, 232 DITypeRef ClassTyRef = DITypeRef()); 233 234 codeview::TypeIndex getMemberFunctionType(const DISubprogram *SP, 235 const DICompositeType *Class); 236 237 codeview::TypeIndex getScopeIndex(const DIScope *Scope); 238 239 codeview::TypeIndex getVBPTypeIndex(); 240 241 void addToUDTs(const DIType *Ty, codeview::TypeIndex TI); 242 243 codeview::TypeIndex lowerType(const DIType *Ty, const DIType *ClassTy); 244 codeview::TypeIndex lowerTypeAlias(const DIDerivedType *Ty); 245 codeview::TypeIndex lowerTypeArray(const DICompositeType *Ty); 246 codeview::TypeIndex lowerTypeBasic(const DIBasicType *Ty); 247 codeview::TypeIndex lowerTypePointer(const DIDerivedType *Ty); 248 codeview::TypeIndex lowerTypeMemberPointer(const DIDerivedType *Ty); 249 codeview::TypeIndex lowerTypeModifier(const DIDerivedType *Ty); 250 codeview::TypeIndex lowerTypeFunction(const DISubroutineType *Ty); 251 codeview::TypeIndex lowerTypeMemberFunction(const DISubroutineType *Ty, 252 const DIType *ClassTy, 253 int ThisAdjustment); 254 codeview::TypeIndex lowerTypeEnum(const DICompositeType *Ty); 255 codeview::TypeIndex lowerTypeClass(const DICompositeType *Ty); 256 codeview::TypeIndex lowerTypeUnion(const DICompositeType *Ty); 257 258 /// Symbol records should point to complete types, but type records should 259 /// always point to incomplete types to avoid cycles in the type graph. Only 260 /// use this entry point when generating symbol records. The complete and 261 /// incomplete type indices only differ for record types. All other types use 262 /// the same index. 263 codeview::TypeIndex getCompleteTypeIndex(DITypeRef TypeRef); 264 265 codeview::TypeIndex lowerCompleteTypeClass(const DICompositeType *Ty); 266 codeview::TypeIndex lowerCompleteTypeUnion(const DICompositeType *Ty); 267 268 struct TypeLoweringScope; 269 270 void emitDeferredCompleteTypes(); 271 272 void collectMemberInfo(ClassInfo &Info, const DIDerivedType *DDTy); 273 ClassInfo collectClassInfo(const DICompositeType *Ty); 274 275 /// Common record member lowering functionality for record types, which are 276 /// structs, classes, and unions. Returns the field list index and the member 277 /// count. 278 std::tuple<codeview::TypeIndex, codeview::TypeIndex, unsigned, bool> 279 lowerRecordFieldList(const DICompositeType *Ty); 280 281 /// Inserts {{Node, ClassTy}, TI} into TypeIndices and checks for duplicates. 282 codeview::TypeIndex recordTypeIndexForDINode(const DINode *Node, 283 codeview::TypeIndex TI, 284 const DIType *ClassTy = nullptr); 285 286 unsigned getPointerSizeInBytes(); 287 288 public: 289 CodeViewDebug(AsmPrinter *Asm); 290 setSymbolSize(const llvm::MCSymbol *,uint64_t)291 void setSymbolSize(const llvm::MCSymbol *, uint64_t) override {} 292 293 /// \brief Emit the COFF section that holds the line table information. 294 void endModule() override; 295 296 /// \brief Gather pre-function debug information. 297 void beginFunction(const MachineFunction *MF) override; 298 299 /// \brief Gather post-function debug information. 300 void endFunction(const MachineFunction *) override; 301 302 /// \brief Process beginning of an instruction. 303 void beginInstruction(const MachineInstr *MI) override; 304 }; 305 } // End of namespace llvm 306 307 #endif 308