1 //===-- llvm/CodeGen/DwarfUnit.h - Dwarf Compile Unit ---*- 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 dwarf compile unit. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #ifndef LLVM_LIB_CODEGEN_ASMPRINTER_DWARFUNIT_H 15 #define LLVM_LIB_CODEGEN_ASMPRINTER_DWARFUNIT_H 16 17 #include "DwarfDebug.h" 18 #include "llvm/ADT/DenseMap.h" 19 #include "llvm/ADT/Optional.h" 20 #include "llvm/ADT/StringMap.h" 21 #include "llvm/CodeGen/AsmPrinter.h" 22 #include "llvm/CodeGen/DIE.h" 23 #include "llvm/IR/DIBuilder.h" 24 #include "llvm/IR/DebugInfo.h" 25 #include "llvm/MC/MCDwarf.h" 26 #include "llvm/MC/MCExpr.h" 27 #include "llvm/MC/MCSection.h" 28 29 namespace llvm { 30 31 class MachineLocation; 32 class MachineOperand; 33 class ConstantInt; 34 class ConstantFP; 35 class DbgVariable; 36 class DwarfCompileUnit; 37 38 // Data structure to hold a range for range lists. 39 class RangeSpan { 40 public: 41 RangeSpan(MCSymbol *S, MCSymbol *E) : Start(S), End(E) {} 42 const MCSymbol *getStart() const { return Start; } 43 const MCSymbol *getEnd() const { return End; } 44 void setEnd(const MCSymbol *E) { End = E; } 45 46 private: 47 const MCSymbol *Start, *End; 48 }; 49 50 class RangeSpanList { 51 private: 52 // Index for locating within the debug_range section this particular span. 53 MCSymbol *RangeSym; 54 // List of ranges. 55 SmallVector<RangeSpan, 2> Ranges; 56 57 public: 58 RangeSpanList(MCSymbol *Sym, SmallVector<RangeSpan, 2> Ranges) 59 : RangeSym(Sym), Ranges(std::move(Ranges)) {} 60 MCSymbol *getSym() const { return RangeSym; } 61 const SmallVectorImpl<RangeSpan> &getRanges() const { return Ranges; } 62 void addRange(RangeSpan Range) { Ranges.push_back(Range); } 63 }; 64 65 //===----------------------------------------------------------------------===// 66 /// This dwarf writer support class manages information associated with a 67 /// source file. 68 class DwarfUnit { 69 protected: 70 /// MDNode for the compile unit. 71 const DICompileUnit *CUNode; 72 73 // All DIEValues are allocated through this allocator. 74 BumpPtrAllocator DIEValueAllocator; 75 76 /// Unit debug information entry. 77 DIE &UnitDie; 78 79 /// Target of Dwarf emission. 80 AsmPrinter *Asm; 81 82 // Holders for some common dwarf information. 83 DwarfDebug *DD; 84 DwarfFile *DU; 85 86 /// An anonymous type for index type. Owned by UnitDie. 87 DIE *IndexTyDie; 88 89 /// Tracks the mapping of unit level debug information variables to debug 90 /// information entries. 91 DenseMap<const MDNode *, DIE *> MDNodeToDieMap; 92 93 /// A list of all the DIEBlocks in use. 94 std::vector<DIEBlock *> DIEBlocks; 95 96 /// A list of all the DIELocs in use. 97 std::vector<DIELoc *> DIELocs; 98 99 /// This map is used to keep track of subprogram DIEs that need 100 /// DW_AT_containing_type attribute. This attribute points to a DIE that 101 /// corresponds to the MDNode mapped with the subprogram DIE. 102 DenseMap<DIE *, const DINode *> ContainingTypeMap; 103 104 /// The section this unit will be emitted in. 105 MCSection *Section; 106 107 DwarfUnit(dwarf::Tag, const DICompileUnit *CU, AsmPrinter *A, DwarfDebug *DW, 108 DwarfFile *DWU); 109 110 bool applySubprogramDefinitionAttributes(const DISubprogram *SP, DIE &SPDie); 111 112 public: 113 virtual ~DwarfUnit(); 114 115 void initSection(MCSection *Section); 116 117 MCSection *getSection() const { 118 assert(Section); 119 return Section; 120 } 121 122 // Accessors. 123 AsmPrinter* getAsmPrinter() const { return Asm; } 124 uint16_t getLanguage() const { return CUNode->getSourceLanguage(); } 125 const DICompileUnit *getCUNode() const { return CUNode; } 126 DIE &getUnitDie() { return UnitDie; } 127 128 /// Return true if this compile unit has something to write out. 129 bool hasContent() const { return UnitDie.hasChildren(); } 130 131 /// Get string containing language specific context for a global name. 132 /// 133 /// Walks the metadata parent chain in a language specific manner (using the 134 /// compile unit language) and returns it as a string. This is done at the 135 /// metadata level because DIEs may not currently have been added to the 136 /// parent context and walking the DIEs looking for names is more expensive 137 /// than walking the metadata. 138 std::string getParentContextString(const DIScope *Context) const; 139 140 /// Add a new global name to the compile unit. 141 virtual void addGlobalName(StringRef Name, DIE &Die, const DIScope *Context) { 142 } 143 144 /// Add a new global type to the compile unit. 145 virtual void addGlobalType(const DIType *Ty, const DIE &Die, 146 const DIScope *Context) {} 147 148 /// Returns the DIE map slot for the specified debug variable. 149 /// 150 /// We delegate the request to DwarfDebug when the MDNode can be part of the 151 /// type system, since DIEs for the type system can be shared across CUs and 152 /// the mappings are kept in DwarfDebug. 153 DIE *getDIE(const DINode *D) const; 154 155 /// Returns a fresh newly allocated DIELoc. 156 DIELoc *getDIELoc() { return new (DIEValueAllocator) DIELoc; } 157 158 /// Insert DIE into the map. 159 /// 160 /// We delegate the request to DwarfDebug when the MDNode can be part of the 161 /// type system, since DIEs for the type system can be shared across CUs and 162 /// the mappings are kept in DwarfDebug. 163 void insertDIE(const DINode *Desc, DIE *D); 164 165 /// Add a flag that is true to the DIE. 166 void addFlag(DIE &Die, dwarf::Attribute Attribute); 167 168 /// Add an unsigned integer attribute data and value. 169 void addUInt(DIEValueList &Die, dwarf::Attribute Attribute, 170 Optional<dwarf::Form> Form, uint64_t Integer); 171 172 void addUInt(DIEValueList &Block, dwarf::Form Form, uint64_t Integer); 173 174 /// Add an signed integer attribute data and value. 175 void addSInt(DIEValueList &Die, dwarf::Attribute Attribute, 176 Optional<dwarf::Form> Form, int64_t Integer); 177 178 void addSInt(DIELoc &Die, Optional<dwarf::Form> Form, int64_t Integer); 179 180 /// Add a string attribute data and value. 181 /// 182 /// We always emit a reference to the string pool instead of immediate 183 /// strings so that DIEs have more predictable sizes. In the case of split 184 /// dwarf we emit an index into another table which gets us the static offset 185 /// into the string table. 186 void addString(DIE &Die, dwarf::Attribute Attribute, StringRef Str); 187 188 /// Add a Dwarf label attribute data and value. 189 DIEValueList::value_iterator addLabel(DIEValueList &Die, 190 dwarf::Attribute Attribute, 191 dwarf::Form Form, 192 const MCSymbol *Label); 193 194 void addLabel(DIELoc &Die, dwarf::Form Form, const MCSymbol *Label); 195 196 /// Add an offset into a section attribute data and value. 197 void addSectionOffset(DIE &Die, dwarf::Attribute Attribute, uint64_t Integer); 198 199 /// Add a dwarf op address data and value using the form given and an 200 /// op of either DW_FORM_addr or DW_FORM_GNU_addr_index. 201 void addOpAddress(DIELoc &Die, const MCSymbol *Label); 202 203 /// Add a label delta attribute data and value. 204 void addLabelDelta(DIE &Die, dwarf::Attribute Attribute, const MCSymbol *Hi, 205 const MCSymbol *Lo); 206 207 /// Add a DIE attribute data and value. 208 void addDIEEntry(DIE &Die, dwarf::Attribute Attribute, DIE &Entry); 209 210 /// Add a DIE attribute data and value. 211 void addDIEEntry(DIE &Die, dwarf::Attribute Attribute, DIEEntry Entry); 212 213 /// Add a type's DW_AT_signature and set the declaration flag. 214 void addDIETypeSignature(DIE &Die, uint64_t Signature); 215 /// Add an attribute containing the type signature for a unique identifier. 216 void addDIETypeSignature(DIE &Die, dwarf::Attribute Attribute, 217 StringRef Identifier); 218 219 /// Add block data. 220 void addBlock(DIE &Die, dwarf::Attribute Attribute, DIELoc *Block); 221 222 /// Add block data. 223 void addBlock(DIE &Die, dwarf::Attribute Attribute, DIEBlock *Block); 224 225 /// Add location information to specified debug information entry. 226 void addSourceLine(DIE &Die, unsigned Line, StringRef File, 227 StringRef Directory); 228 void addSourceLine(DIE &Die, const DILocalVariable *V); 229 void addSourceLine(DIE &Die, const DIGlobalVariable *G); 230 void addSourceLine(DIE &Die, const DISubprogram *SP); 231 void addSourceLine(DIE &Die, const DIType *Ty); 232 void addSourceLine(DIE &Die, const DINamespace *NS); 233 void addSourceLine(DIE &Die, const DIObjCProperty *Ty); 234 235 /// Add constant value entry in variable DIE. 236 void addConstantValue(DIE &Die, const MachineOperand &MO, const DIType *Ty); 237 void addConstantValue(DIE &Die, const ConstantInt *CI, const DIType *Ty); 238 void addConstantValue(DIE &Die, const APInt &Val, const DIType *Ty); 239 void addConstantValue(DIE &Die, const APInt &Val, bool Unsigned); 240 void addConstantValue(DIE &Die, bool Unsigned, uint64_t Val); 241 242 /// Add constant value entry in variable DIE. 243 void addConstantFPValue(DIE &Die, const MachineOperand &MO); 244 void addConstantFPValue(DIE &Die, const ConstantFP *CFP); 245 246 /// Add a linkage name, if it isn't empty. 247 void addLinkageName(DIE &Die, StringRef LinkageName); 248 249 /// Add template parameters in buffer. 250 void addTemplateParams(DIE &Buffer, DINodeArray TParams); 251 252 /// Add register operand. 253 /// \returns false if the register does not exist, e.g., because it was never 254 /// materialized. 255 bool addRegisterOpPiece(DIELoc &TheDie, unsigned Reg, 256 unsigned SizeInBits = 0, unsigned OffsetInBits = 0); 257 258 /// Add register offset. 259 /// \returns false if the register does not exist, e.g., because it was never 260 /// materialized. 261 bool addRegisterOffset(DIELoc &TheDie, unsigned Reg, int64_t Offset); 262 263 // FIXME: Should be reformulated in terms of addComplexAddress. 264 /// Start with the address based on the location provided, and generate the 265 /// DWARF information necessary to find the actual Block variable (navigating 266 /// the Block struct) based on the starting location. Add the DWARF 267 /// information to the die. Obsolete, please use addComplexAddress instead. 268 void addBlockByrefAddress(const DbgVariable &DV, DIE &Die, 269 dwarf::Attribute Attribute, 270 const MachineLocation &Location); 271 272 /// Add a new type attribute to the specified entity. 273 /// 274 /// This takes and attribute parameter because DW_AT_friend attributes are 275 /// also type references. 276 void addType(DIE &Entity, const DIType *Ty, 277 dwarf::Attribute Attribute = dwarf::DW_AT_type); 278 279 DIE *getOrCreateNameSpace(const DINamespace *NS); 280 DIE *getOrCreateModule(const DIModule *M); 281 DIE *getOrCreateSubprogramDIE(const DISubprogram *SP, bool Minimal = false); 282 283 void applySubprogramAttributes(const DISubprogram *SP, DIE &SPDie, 284 bool Minimal = false); 285 286 /// Find existing DIE or create new DIE for the given type. 287 DIE *getOrCreateTypeDIE(const MDNode *N); 288 289 /// Get context owner's DIE. 290 DIE *createTypeDIE(const DICompositeType *Ty); 291 292 /// Get context owner's DIE. 293 DIE *getOrCreateContextDIE(const DIScope *Context); 294 295 /// Construct DIEs for types that contain vtables. 296 void constructContainingTypeDIEs(); 297 298 /// Construct function argument DIEs. 299 void constructSubprogramArguments(DIE &Buffer, DITypeRefArray Args); 300 301 /// Create a DIE with the given Tag, add the DIE to its parent, and 302 /// call insertDIE if MD is not null. 303 DIE &createAndAddDIE(unsigned Tag, DIE &Parent, const DINode *N = nullptr); 304 305 /// Compute the size of a header for this unit, not including the initial 306 /// length field. 307 virtual unsigned getHeaderSize() const { 308 return sizeof(int16_t) + // DWARF version number 309 sizeof(int32_t) + // Offset Into Abbrev. Section 310 sizeof(int8_t); // Pointer Size (in bytes) 311 } 312 313 /// Emit the header for this unit, not including the initial length field. 314 virtual void emitHeader(bool UseOffsets); 315 316 virtual DwarfCompileUnit &getCU() = 0; 317 318 void constructTypeDIE(DIE &Buffer, const DICompositeType *CTy); 319 320 protected: 321 /// Create new static data member DIE. 322 DIE *getOrCreateStaticMemberDIE(const DIDerivedType *DT); 323 324 /// Look up the source ID with the given directory and source file names. If 325 /// none currently exists, create a new ID and insert it in the line table. 326 virtual unsigned getOrCreateSourceID(StringRef File, StringRef Directory) = 0; 327 328 /// Look in the DwarfDebug map for the MDNode that corresponds to the 329 /// reference. 330 template <typename T> T *resolve(TypedDINodeRef<T> Ref) const { 331 return Ref.resolve(); 332 } 333 334 private: 335 void constructTypeDIE(DIE &Buffer, const DIBasicType *BTy); 336 void constructTypeDIE(DIE &Buffer, const DIDerivedType *DTy); 337 void constructTypeDIE(DIE &Buffer, const DISubroutineType *DTy); 338 void constructSubrangeDIE(DIE &Buffer, const DISubrange *SR, DIE *IndexTy); 339 void constructArrayTypeDIE(DIE &Buffer, const DICompositeType *CTy); 340 void constructEnumTypeDIE(DIE &Buffer, const DICompositeType *CTy); 341 void constructMemberDIE(DIE &Buffer, const DIDerivedType *DT); 342 void constructTemplateTypeParameterDIE(DIE &Buffer, 343 const DITemplateTypeParameter *TP); 344 void constructTemplateValueParameterDIE(DIE &Buffer, 345 const DITemplateValueParameter *TVP); 346 347 /// Return the default lower bound for an array. 348 /// 349 /// If the DWARF version doesn't handle the language, return -1. 350 int64_t getDefaultLowerBound() const; 351 352 /// Get an anonymous type for index type. 353 DIE *getIndexTyDie(); 354 355 /// Set D as anonymous type for index which can be reused later. 356 void setIndexTyDie(DIE *D) { IndexTyDie = D; } 357 358 /// If this is a named finished type then include it in the list of types for 359 /// the accelerator tables. 360 void updateAcceleratorTables(const DIScope *Context, const DIType *Ty, 361 const DIE &TyDIE); 362 363 virtual bool isDwoUnit() const = 0; 364 }; 365 366 class DwarfTypeUnit : public DwarfUnit { 367 uint64_t TypeSignature; 368 const DIE *Ty; 369 DwarfCompileUnit &CU; 370 MCDwarfDwoLineTable *SplitLineTable; 371 372 unsigned getOrCreateSourceID(StringRef File, StringRef Directory) override; 373 bool isDwoUnit() const override; 374 375 public: 376 DwarfTypeUnit(DwarfCompileUnit &CU, AsmPrinter *A, DwarfDebug *DW, 377 DwarfFile *DWU, MCDwarfDwoLineTable *SplitLineTable = nullptr); 378 379 void setTypeSignature(uint64_t Signature) { TypeSignature = Signature; } 380 void setType(const DIE *Ty) { this->Ty = Ty; } 381 382 /// Emit the header for this unit, not including the initial length field. 383 void emitHeader(bool UseOffsets) override; 384 unsigned getHeaderSize() const override { 385 return DwarfUnit::getHeaderSize() + sizeof(uint64_t) + // Type Signature 386 sizeof(uint32_t); // Type DIE Offset 387 } 388 DwarfCompileUnit &getCU() override { return CU; } 389 }; 390 } // end llvm namespace 391 #endif 392
