src/llvm/include/llvm/CodeGen/DIE.h

   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 LLVM_LIB_CODEGEN_ASMPRINTER_DIE_H
  15 #define LLVM_LIB_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:
  42   DIEAbbrevData(dwarf::Attribute A, dwarf::Form F) : Attribute(A), Form(F) {}
  43
  44   // Accessors.
  45   dwarf::Attribute getAttribute() const { return Attribute; }
  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:
  76   DIEAbbrev(dwarf::Tag T, bool C) : Tag(T), Children(C), Data() {}
  77
  78   // Accessors.
  79   dwarf::Tag getTag() const { return Tag; }
  80   unsigned getNumber() const { return Number; }
  81   bool hasChildren() const { return Children; }
  82   const SmallVectorImpl<DIEAbbrevData> &getData() const { return Data; }
  83   void setChildrenFlag(bool hasChild) { Children = hasChild; }
  84   void setNumber(unsigned N) { Number = N; }
  85
  86   /// AddAttribute - Adds another set of attribute information to the
  87   /// abbreviation.
  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:
 142   DIE()
 143       : Offset(0), Size(0), Abbrev((dwarf::Tag)0, dwarf::DW_CHILDREN_no),
 144         Parent(nullptr) {}
 145
 146 public:
 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.
 152   DIEAbbrev &getAbbrev() { return Abbrev; }
 153   const DIEAbbrev &getAbbrev() const { return Abbrev; }
 154   unsigned getAbbrevNumber() const { return Abbrev.getNumber(); }
 155   dwarf::Tag getTag() const { return Abbrev.getTag(); }
 156   unsigned getOffset() const { return Offset; }
 157   unsigned getSize() const { return Size; }
 158   const std::vector<std::unique_ptr<DIE>> &getChildren() const {
 159     return Children;
 160   }
 161   const SmallVectorImpl<DIEValue *> &getValues() const { return Values; }
 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;
 169   void setOffset(unsigned O) { Offset = O; }
 170   void setSize(unsigned S) { Size = S; }
 171
 172   /// addValue - Add a value and attributes to a DIE.
 173   ///
 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   ///
 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
 224   explicit DIEValue(Type T) : Ty(T) {}
 225   virtual ~DIEValue() {}
 226
 227 public:
 228   // Accessors
 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:
 252   explicit DIEInteger(uint64_t I) : DIEValue(isInteger), Integer(I) {}
 253
 254   /// BestForm - Choose the best form for integer.
 255   ///
 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
 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.
 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:
 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   ///
 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.
 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:
 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   ///
 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.
 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:
 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.
 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   StringRef Str;
 385
 386 public:
 387   DIEString(const DIEValue *Acc, StringRef S)
 388       : DIEValue(isString), Access(Acc), Str(S) {}
 389
 390   /// getString - Grab the string out of the object.
 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.
 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:
 417   explicit DIEEntry(DIE &E) : DIEValue(isEntry), Entry(E) {
 418   }
 419
 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   ///
 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.
 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:
 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.
 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.
 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:
 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   ///
 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.
 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:
 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   ///
 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.
 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:
 564   DIELocList(size_t I) : DIEValue(isLocList), Index(I) {}
 565
 566   /// getValue - Grab the current index out.
 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.
 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