1 //===--- lib/CodeGen/DIE.h - DWARF Info Entries -----------------*- 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 // Data structures for DWARF info entries. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #ifndef CODEGEN_ASMPRINTER_DIE_H__ 15 #define CODEGEN_ASMPRINTER_DIE_H__ 16 17 #include "llvm/ADT/FoldingSet.h" 18 #include "llvm/ADT/SmallVector.h" 19 #include "llvm/Support/Dwarf.h" 20 #include <vector> 21 22 namespace llvm { 23 class AsmPrinter; 24 class MCExpr; 25 class MCSymbol; 26 class raw_ostream; 27 class DwarfTypeUnit; 28 29 //===--------------------------------------------------------------------===// 30 /// DIEAbbrevData - Dwarf abbreviation data, describes one attribute of a 31 /// Dwarf abbreviation. 32 class DIEAbbrevData { 33 /// Attribute - Dwarf attribute code. 34 /// 35 dwarf::Attribute Attribute; 36 37 /// Form - Dwarf form code. 38 /// 39 dwarf::Form Form; 40 41 public: DIEAbbrevData(dwarf::Attribute A,dwarf::Form F)42 DIEAbbrevData(dwarf::Attribute A, dwarf::Form F) : Attribute(A), Form(F) {} 43 44 // Accessors. getAttribute()45 dwarf::Attribute getAttribute() const { return Attribute; } getForm()46 dwarf::Form getForm() const { return Form; } 47 48 /// Profile - Used to gather unique data for the abbreviation folding set. 49 /// 50 void Profile(FoldingSetNodeID &ID) const; 51 }; 52 53 //===--------------------------------------------------------------------===// 54 /// DIEAbbrev - Dwarf abbreviation, describes the organization of a debug 55 /// information object. 56 class DIEAbbrev : public FoldingSetNode { 57 /// Unique number for node. 58 /// 59 unsigned Number; 60 61 /// Tag - Dwarf tag code. 62 /// 63 dwarf::Tag Tag; 64 65 /// Children - Whether or not this node has children. 66 /// 67 // This cheats a bit in all of the uses since the values in the standard 68 // are 0 and 1 for no children and children respectively. 69 bool Children; 70 71 /// Data - Raw data bytes for abbreviation. 72 /// 73 SmallVector<DIEAbbrevData, 12> Data; 74 75 public: DIEAbbrev(dwarf::Tag T,bool C)76 DIEAbbrev(dwarf::Tag T, bool C) : Tag(T), Children(C), Data() {} 77 78 // Accessors. getTag()79 dwarf::Tag getTag() const { return Tag; } getNumber()80 unsigned getNumber() const { return Number; } hasChildren()81 bool hasChildren() const { return Children; } getData()82 const SmallVectorImpl<DIEAbbrevData> &getData() const { return Data; } setChildrenFlag(bool hasChild)83 void setChildrenFlag(bool hasChild) { Children = hasChild; } setNumber(unsigned N)84 void setNumber(unsigned N) { Number = N; } 85 86 /// AddAttribute - Adds another set of attribute information to the 87 /// abbreviation. AddAttribute(dwarf::Attribute Attribute,dwarf::Form Form)88 void AddAttribute(dwarf::Attribute Attribute, dwarf::Form Form) { 89 Data.push_back(DIEAbbrevData(Attribute, Form)); 90 } 91 92 /// Profile - Used to gather unique data for the abbreviation folding set. 93 /// 94 void Profile(FoldingSetNodeID &ID) const; 95 96 /// Emit - Print the abbreviation using the specified asm printer. 97 /// 98 void Emit(AsmPrinter *AP) const; 99 100 #ifndef NDEBUG 101 void print(raw_ostream &O); 102 void dump(); 103 #endif 104 }; 105 106 //===--------------------------------------------------------------------===// 107 /// DIE - A structured debug information entry. Has an abbreviation which 108 /// describes its organization. 109 class DIEValue; 110 111 class DIE { 112 protected: 113 /// Offset - Offset in debug info section. 114 /// 115 unsigned Offset; 116 117 /// Size - Size of instance + children. 118 /// 119 unsigned Size; 120 121 /// Abbrev - Buffer for constructing abbreviation. 122 /// 123 DIEAbbrev Abbrev; 124 125 /// Children DIEs. 126 /// 127 // This can't be a vector<DIE> because pointer validity is requirent for the 128 // Parent pointer and DIEEntry. 129 // It can't be a list<DIE> because some clients need pointer validity before 130 // the object has been added to any child list 131 // (eg: DwarfUnit::constructVariableDIE). These aren't insurmountable, but may 132 // be more convoluted than beneficial. 133 std::vector<std::unique_ptr<DIE>> Children; 134 135 DIE *Parent; 136 137 /// Attribute values. 138 /// 139 SmallVector<DIEValue *, 12> Values; 140 141 protected: DIE()142 DIE() 143 : Offset(0), Size(0), Abbrev((dwarf::Tag)0, dwarf::DW_CHILDREN_no), 144 Parent(nullptr) {} 145 146 public: DIE(dwarf::Tag Tag)147 explicit DIE(dwarf::Tag Tag) 148 : Offset(0), Size(0), Abbrev((dwarf::Tag)Tag, dwarf::DW_CHILDREN_no), 149 Parent(nullptr) {} 150 151 // Accessors. getAbbrev()152 DIEAbbrev &getAbbrev() { return Abbrev; } getAbbrev()153 const DIEAbbrev &getAbbrev() const { return Abbrev; } getAbbrevNumber()154 unsigned getAbbrevNumber() const { return Abbrev.getNumber(); } getTag()155 dwarf::Tag getTag() const { return Abbrev.getTag(); } getOffset()156 unsigned getOffset() const { return Offset; } getSize()157 unsigned getSize() const { return Size; } getChildren()158 const std::vector<std::unique_ptr<DIE>> &getChildren() const { 159 return Children; 160 } getValues()161 const SmallVectorImpl<DIEValue *> &getValues() const { return Values; } getParent()162 DIE *getParent() const { return Parent; } 163 /// Climb up the parent chain to get the compile or type unit DIE this DIE 164 /// belongs to. 165 const DIE *getUnit() const; 166 /// Similar to getUnit, returns null when DIE is not added to an 167 /// owner yet. 168 const DIE *getUnitOrNull() const; setOffset(unsigned O)169 void setOffset(unsigned O) { Offset = O; } setSize(unsigned S)170 void setSize(unsigned S) { Size = S; } 171 172 /// addValue - Add a value and attributes to a DIE. 173 /// addValue(dwarf::Attribute Attribute,dwarf::Form Form,DIEValue * Value)174 void addValue(dwarf::Attribute Attribute, dwarf::Form Form, DIEValue *Value) { 175 Abbrev.AddAttribute(Attribute, Form); 176 Values.push_back(Value); 177 } 178 179 /// addChild - Add a child to the DIE. 180 /// addChild(std::unique_ptr<DIE> Child)181 void addChild(std::unique_ptr<DIE> Child) { 182 assert(!Child->getParent()); 183 Abbrev.setChildrenFlag(dwarf::DW_CHILDREN_yes); 184 Child->Parent = this; 185 Children.push_back(std::move(Child)); 186 } 187 188 /// findAttribute - Find a value in the DIE with the attribute given, 189 /// returns NULL if no such attribute exists. 190 DIEValue *findAttribute(dwarf::Attribute Attribute) const; 191 192 #ifndef NDEBUG 193 void print(raw_ostream &O, unsigned IndentCount = 0) const; 194 void dump(); 195 #endif 196 }; 197 198 //===--------------------------------------------------------------------===// 199 /// DIEValue - A debug information entry value. Some of these roughly correlate 200 /// to DWARF attribute classes. 201 /// 202 class DIEValue { 203 virtual void anchor(); 204 205 public: 206 enum Type { 207 isInteger, 208 isString, 209 isExpr, 210 isLabel, 211 isDelta, 212 isEntry, 213 isTypeSignature, 214 isBlock, 215 isLoc, 216 isLocList, 217 }; 218 219 protected: 220 /// Ty - Type of data stored in the value. 221 /// 222 Type Ty; 223 DIEValue(Type T)224 explicit DIEValue(Type T) : Ty(T) {} ~DIEValue()225 virtual ~DIEValue() {} 226 227 public: 228 // Accessors getType()229 Type getType() const { return Ty; } 230 231 /// EmitValue - Emit value via the Dwarf writer. 232 /// 233 virtual void EmitValue(AsmPrinter *AP, dwarf::Form Form) const = 0; 234 235 /// SizeOf - Return the size of a value in bytes. 236 /// 237 virtual unsigned SizeOf(AsmPrinter *AP, dwarf::Form Form) const = 0; 238 239 #ifndef NDEBUG 240 virtual void print(raw_ostream &O) const = 0; 241 void dump() const; 242 #endif 243 }; 244 245 //===--------------------------------------------------------------------===// 246 /// DIEInteger - An integer value DIE. 247 /// 248 class DIEInteger : public DIEValue { 249 uint64_t Integer; 250 251 public: DIEInteger(uint64_t I)252 explicit DIEInteger(uint64_t I) : DIEValue(isInteger), Integer(I) {} 253 254 /// BestForm - Choose the best form for integer. 255 /// BestForm(bool IsSigned,uint64_t Int)256 static dwarf::Form BestForm(bool IsSigned, uint64_t Int) { 257 if (IsSigned) { 258 const int64_t SignedInt = Int; 259 if ((char)Int == SignedInt) 260 return dwarf::DW_FORM_data1; 261 if ((short)Int == SignedInt) 262 return dwarf::DW_FORM_data2; 263 if ((int)Int == SignedInt) 264 return dwarf::DW_FORM_data4; 265 } else { 266 if ((unsigned char)Int == Int) 267 return dwarf::DW_FORM_data1; 268 if ((unsigned short)Int == Int) 269 return dwarf::DW_FORM_data2; 270 if ((unsigned int)Int == Int) 271 return dwarf::DW_FORM_data4; 272 } 273 return dwarf::DW_FORM_data8; 274 } 275 276 /// EmitValue - Emit integer of appropriate size. 277 /// 278 void EmitValue(AsmPrinter *AP, dwarf::Form Form) const override; 279 getValue()280 uint64_t getValue() const { return Integer; } 281 282 /// SizeOf - Determine size of integer value in bytes. 283 /// 284 unsigned SizeOf(AsmPrinter *AP, dwarf::Form Form) const override; 285 286 // Implement isa/cast/dyncast. classof(const DIEValue * I)287 static bool classof(const DIEValue *I) { return I->getType() == isInteger; } 288 289 #ifndef NDEBUG 290 void print(raw_ostream &O) const override; 291 #endif 292 }; 293 294 //===--------------------------------------------------------------------===// 295 /// DIEExpr - An expression DIE. 296 // 297 class DIEExpr : public DIEValue { 298 const MCExpr *Expr; 299 300 public: DIEExpr(const MCExpr * E)301 explicit DIEExpr(const MCExpr *E) : DIEValue(isExpr), Expr(E) {} 302 303 /// EmitValue - Emit expression value. 304 /// 305 void EmitValue(AsmPrinter *AP, dwarf::Form Form) const override; 306 307 /// getValue - Get MCExpr. 308 /// getValue()309 const MCExpr *getValue() const { return Expr; } 310 311 /// SizeOf - Determine size of expression value in bytes. 312 /// 313 unsigned SizeOf(AsmPrinter *AP, dwarf::Form Form) const override; 314 315 // Implement isa/cast/dyncast. classof(const DIEValue * E)316 static bool classof(const DIEValue *E) { return E->getType() == isExpr; } 317 318 #ifndef NDEBUG 319 void print(raw_ostream &O) const override; 320 #endif 321 }; 322 323 //===--------------------------------------------------------------------===// 324 /// DIELabel - A label DIE. 325 // 326 class DIELabel : public DIEValue { 327 const MCSymbol *Label; 328 329 public: DIELabel(const MCSymbol * L)330 explicit DIELabel(const MCSymbol *L) : DIEValue(isLabel), Label(L) {} 331 332 /// EmitValue - Emit label value. 333 /// 334 void EmitValue(AsmPrinter *AP, dwarf::Form Form) const override; 335 336 /// getValue - Get MCSymbol. 337 /// getValue()338 const MCSymbol *getValue() const { return Label; } 339 340 /// SizeOf - Determine size of label value in bytes. 341 /// 342 unsigned SizeOf(AsmPrinter *AP, dwarf::Form Form) const override; 343 344 // Implement isa/cast/dyncast. classof(const DIEValue * L)345 static bool classof(const DIEValue *L) { return L->getType() == isLabel; } 346 347 #ifndef NDEBUG 348 void print(raw_ostream &O) const override; 349 #endif 350 }; 351 352 //===--------------------------------------------------------------------===// 353 /// DIEDelta - A simple label difference DIE. 354 /// 355 class DIEDelta : public DIEValue { 356 const MCSymbol *LabelHi; 357 const MCSymbol *LabelLo; 358 359 public: DIEDelta(const MCSymbol * Hi,const MCSymbol * Lo)360 DIEDelta(const MCSymbol *Hi, const MCSymbol *Lo) 361 : DIEValue(isDelta), LabelHi(Hi), LabelLo(Lo) {} 362 363 /// EmitValue - Emit delta value. 364 /// 365 void EmitValue(AsmPrinter *AP, dwarf::Form Form) const override; 366 367 /// SizeOf - Determine size of delta value in bytes. 368 /// 369 unsigned SizeOf(AsmPrinter *AP, dwarf::Form Form) const override; 370 371 // Implement isa/cast/dyncast. classof(const DIEValue * D)372 static bool classof(const DIEValue *D) { return D->getType() == isDelta; } 373 374 #ifndef NDEBUG 375 void print(raw_ostream &O) const override; 376 #endif 377 }; 378 379 //===--------------------------------------------------------------------===// 380 /// DIEString - A container for string values. 381 /// 382 class DIEString : public DIEValue { 383 const DIEValue *Access; 384 const StringRef Str; 385 386 public: DIEString(const DIEValue * Acc,const StringRef S)387 DIEString(const DIEValue *Acc, const StringRef S) 388 : DIEValue(isString), Access(Acc), Str(S) {} 389 390 /// getString - Grab the string out of the object. getString()391 StringRef getString() const { return Str; } 392 393 /// EmitValue - Emit delta value. 394 /// 395 void EmitValue(AsmPrinter *AP, dwarf::Form Form) const override; 396 397 /// SizeOf - Determine size of delta value in bytes. 398 /// 399 unsigned SizeOf(AsmPrinter *AP, dwarf::Form Form) const override; 400 401 // Implement isa/cast/dyncast. classof(const DIEValue * D)402 static bool classof(const DIEValue *D) { return D->getType() == isString; } 403 404 #ifndef NDEBUG 405 void print(raw_ostream &O) const override; 406 #endif 407 }; 408 409 //===--------------------------------------------------------------------===// 410 /// DIEEntry - A pointer to another debug information entry. An instance of 411 /// this class can also be used as a proxy for a debug information entry not 412 /// yet defined (ie. types.) 413 class DIEEntry : public DIEValue { 414 DIE &Entry; 415 416 public: DIEEntry(DIE & E)417 explicit DIEEntry(DIE &E) : DIEValue(isEntry), Entry(E) { 418 } 419 getEntry()420 DIE &getEntry() const { return Entry; } 421 422 /// EmitValue - Emit debug information entry offset. 423 /// 424 void EmitValue(AsmPrinter *AP, dwarf::Form Form) const override; 425 426 /// SizeOf - Determine size of debug information entry in bytes. 427 /// SizeOf(AsmPrinter * AP,dwarf::Form Form)428 unsigned SizeOf(AsmPrinter *AP, dwarf::Form Form) const override { 429 return Form == dwarf::DW_FORM_ref_addr ? getRefAddrSize(AP) 430 : sizeof(int32_t); 431 } 432 433 /// Returns size of a ref_addr entry. 434 static unsigned getRefAddrSize(AsmPrinter *AP); 435 436 // Implement isa/cast/dyncast. classof(const DIEValue * E)437 static bool classof(const DIEValue *E) { return E->getType() == isEntry; } 438 439 #ifndef NDEBUG 440 void print(raw_ostream &O) const override; 441 #endif 442 }; 443 444 //===--------------------------------------------------------------------===// 445 /// \brief A signature reference to a type unit. 446 class DIETypeSignature : public DIEValue { 447 const DwarfTypeUnit &Unit; 448 449 public: DIETypeSignature(const DwarfTypeUnit & Unit)450 explicit DIETypeSignature(const DwarfTypeUnit &Unit) 451 : DIEValue(isTypeSignature), Unit(Unit) {} 452 453 /// \brief Emit type unit signature. 454 void EmitValue(AsmPrinter *Asm, dwarf::Form Form) const override; 455 456 /// Returns size of a ref_sig8 entry. SizeOf(AsmPrinter * AP,dwarf::Form Form)457 unsigned SizeOf(AsmPrinter *AP, dwarf::Form Form) const override { 458 assert(Form == dwarf::DW_FORM_ref_sig8); 459 return 8; 460 } 461 462 // \brief Implement isa/cast/dyncast. classof(const DIEValue * E)463 static bool classof(const DIEValue *E) { 464 return E->getType() == isTypeSignature; 465 } 466 #ifndef NDEBUG 467 void print(raw_ostream &O) const override; 468 void dump() const; 469 #endif 470 }; 471 472 //===--------------------------------------------------------------------===// 473 /// DIELoc - Represents an expression location. 474 // 475 class DIELoc : public DIEValue, public DIE { 476 mutable unsigned Size; // Size in bytes excluding size header. 477 public: DIELoc()478 DIELoc() : DIEValue(isLoc), Size(0) {} 479 480 /// ComputeSize - Calculate the size of the location expression. 481 /// 482 unsigned ComputeSize(AsmPrinter *AP) const; 483 484 /// BestForm - Choose the best form for data. 485 /// BestForm(unsigned DwarfVersion)486 dwarf::Form BestForm(unsigned DwarfVersion) const { 487 if (DwarfVersion > 3) 488 return dwarf::DW_FORM_exprloc; 489 // Pre-DWARF4 location expressions were blocks and not exprloc. 490 if ((unsigned char)Size == Size) 491 return dwarf::DW_FORM_block1; 492 if ((unsigned short)Size == Size) 493 return dwarf::DW_FORM_block2; 494 if ((unsigned int)Size == Size) 495 return dwarf::DW_FORM_block4; 496 return dwarf::DW_FORM_block; 497 } 498 499 /// EmitValue - Emit location data. 500 /// 501 void EmitValue(AsmPrinter *AP, dwarf::Form Form) const override; 502 503 /// SizeOf - Determine size of location data in bytes. 504 /// 505 unsigned SizeOf(AsmPrinter *AP, dwarf::Form Form) const override; 506 507 // Implement isa/cast/dyncast. classof(const DIEValue * E)508 static bool classof(const DIEValue *E) { return E->getType() == isLoc; } 509 510 #ifndef NDEBUG 511 void print(raw_ostream &O) const override; 512 #endif 513 }; 514 515 //===--------------------------------------------------------------------===// 516 /// DIEBlock - Represents a block of values. 517 // 518 class DIEBlock : public DIEValue, public DIE { 519 mutable unsigned Size; // Size in bytes excluding size header. 520 public: DIEBlock()521 DIEBlock() : DIEValue(isBlock), Size(0) {} 522 523 /// ComputeSize - Calculate the size of the location expression. 524 /// 525 unsigned ComputeSize(AsmPrinter *AP) const; 526 527 /// BestForm - Choose the best form for data. 528 /// BestForm()529 dwarf::Form BestForm() const { 530 if ((unsigned char)Size == Size) 531 return dwarf::DW_FORM_block1; 532 if ((unsigned short)Size == Size) 533 return dwarf::DW_FORM_block2; 534 if ((unsigned int)Size == Size) 535 return dwarf::DW_FORM_block4; 536 return dwarf::DW_FORM_block; 537 } 538 539 /// EmitValue - Emit location data. 540 /// 541 void EmitValue(AsmPrinter *AP, dwarf::Form Form) const override; 542 543 /// SizeOf - Determine size of location data in bytes. 544 /// 545 unsigned SizeOf(AsmPrinter *AP, dwarf::Form Form) const override; 546 547 // Implement isa/cast/dyncast. classof(const DIEValue * E)548 static bool classof(const DIEValue *E) { return E->getType() == isBlock; } 549 550 #ifndef NDEBUG 551 void print(raw_ostream &O) const override; 552 #endif 553 }; 554 555 //===--------------------------------------------------------------------===// 556 /// DIELocList - Represents a pointer to a location list in the debug_loc 557 /// section. 558 // 559 class DIELocList : public DIEValue { 560 // Index into the .debug_loc vector. 561 size_t Index; 562 563 public: DIELocList(size_t I)564 DIELocList(size_t I) : DIEValue(isLocList), Index(I) {} 565 566 /// getValue - Grab the current index out. getValue()567 size_t getValue() const { return Index; } 568 569 /// EmitValue - Emit location data. 570 /// 571 void EmitValue(AsmPrinter *AP, dwarf::Form Form) const override; 572 573 /// SizeOf - Determine size of location data in bytes. 574 /// 575 unsigned SizeOf(AsmPrinter *AP, dwarf::Form Form) const override; 576 577 // Implement isa/cast/dyncast. classof(const DIEValue * E)578 static bool classof(const DIEValue *E) { return E->getType() == isLocList; } 579 580 #ifndef NDEBUG 581 void print(raw_ostream &O) const override; 582 #endif 583 }; 584 585 } // end llvm namespace 586 587 #endif 588