CFG.h revision 4ba72a0b28135209c435630682febe1f854ccfa6
1//===--- CFG.h - Classes for representing and building CFGs------*- 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 defines the CFG and CFGBuilder classes for representing and 11// building Control-Flow Graphs (CFGs) from ASTs. 12// 13//===----------------------------------------------------------------------===// 14 15#ifndef LLVM_CLANG_CFG_H 16#define LLVM_CLANG_CFG_H 17 18#include "llvm/ADT/PointerIntPair.h" 19#include "llvm/ADT/GraphTraits.h" 20#include "llvm/Support/Allocator.h" 21#include "llvm/Support/Casting.h" 22#include "clang/Analysis/Support/BumpVector.h" 23#include "clang/Basic/SourceLocation.h" 24#include <cassert> 25 26namespace llvm { 27 class raw_ostream; 28} 29 30namespace clang { 31 class Decl; 32 class Stmt; 33 class Expr; 34 class FieldDecl; 35 class VarDecl; 36 class CXXBaseOrMemberInitializer; 37 class CXXBaseSpecifier; 38 class CFG; 39 class PrinterHelper; 40 class LangOptions; 41 class ASTContext; 42 43/// CFGElement - Represents a top-level expression in a basic block. 44class CFGElement { 45public: 46 enum Kind { 47 // main kind 48 Statement, 49 StatementAsLValue, 50 Initializer, 51 Dtor, 52 // dtor kind 53 AutomaticObjectDtor, 54 BaseDtor, 55 MemberDtor, 56 TemporaryDtor, 57 DTOR_BEGIN = AutomaticObjectDtor 58 }; 59 60protected: 61 // The int bits are used to mark the main kind. 62 llvm::PointerIntPair<void *, 2> Data1; 63 // The int bits are used to mark the dtor kind. 64 llvm::PointerIntPair<void *, 2> Data2; 65 66 CFGElement(void *Ptr, unsigned Int) : Data1(Ptr, Int) {} 67 CFGElement(void *Ptr1, unsigned Int1, void *Ptr2, unsigned Int2) 68 : Data1(Ptr1, Int1), Data2(Ptr2, Int2) {} 69 70public: 71 CFGElement() {} 72 73 Kind getKind() const { return static_cast<Kind>(Data1.getInt()); } 74 75 Kind getDtorKind() const { 76 assert(getKind() == Dtor); 77 return static_cast<Kind>(Data2.getInt() + DTOR_BEGIN); 78 } 79 80 bool isValid() const { return Data1.getPointer(); } 81 82 operator bool() const { return isValid(); } 83 84 template<class ElemTy> ElemTy getAs() const { 85 if (llvm::isa<ElemTy>(this)) 86 return *static_cast<const ElemTy*>(this); 87 return ElemTy(); 88 } 89 90 static bool classof(const CFGElement *E) { return true; } 91}; 92 93class CFGStmt : public CFGElement { 94public: 95 CFGStmt() {} 96 CFGStmt(Stmt *S, bool asLValue) : CFGElement(S, asLValue) {} 97 98 Stmt *getStmt() const { return static_cast<Stmt *>(Data1.getPointer()); } 99 100 operator Stmt*() const { return getStmt(); } 101 102 bool asLValue() const { 103 return static_cast<Kind>(Data1.getInt()) == StatementAsLValue; 104 } 105 106 static bool classof(const CFGElement *E) { 107 return E->getKind() == Statement || E->getKind() == StatementAsLValue; 108 } 109}; 110 111/// CFGInitializer - Represents C++ base or member initializer from 112/// constructor's initialization list. 113class CFGInitializer : public CFGElement { 114public: 115 CFGInitializer() {} 116 CFGInitializer(CXXBaseOrMemberInitializer* I) 117 : CFGElement(I, Initializer) {} 118 119 CXXBaseOrMemberInitializer* getInitializer() const { 120 return static_cast<CXXBaseOrMemberInitializer*>(Data1.getPointer()); 121 } 122 operator CXXBaseOrMemberInitializer*() const { return getInitializer(); } 123 124 static bool classof(const CFGElement *E) { 125 return E->getKind() == Initializer; 126 } 127}; 128 129/// CFGImplicitDtor - Represents C++ object destructor implicitly generated 130/// by compiler on various occasions. 131class CFGImplicitDtor : public CFGElement { 132protected: 133 CFGImplicitDtor(unsigned K, void* P, void* S) 134 : CFGElement(P, Dtor, S, K - DTOR_BEGIN) {} 135 136public: 137 CFGImplicitDtor() {} 138 139 static bool classof(const CFGElement *E) { 140 return E->getKind() == Dtor; 141 } 142}; 143 144/// CFGAutomaticObjDtor - Represents C++ object destructor implicitly generated 145/// for automatic object or temporary bound to const reference at the point 146/// of leaving its local scope. 147class CFGAutomaticObjDtor: public CFGImplicitDtor { 148public: 149 CFGAutomaticObjDtor() {} 150 CFGAutomaticObjDtor(VarDecl* VD, Stmt* S) 151 : CFGImplicitDtor(AutomaticObjectDtor, VD, S) {} 152 153 VarDecl* getVarDecl() const { 154 return static_cast<VarDecl*>(Data1.getPointer()); 155 } 156 157 // Get statement end of which triggered the destructor call. 158 Stmt* getTriggerStmt() const { 159 return static_cast<Stmt*>(Data2.getPointer()); 160 } 161 162 static bool classof(const CFGElement *E) { 163 return E->getKind() == Dtor && E->getDtorKind() == AutomaticObjectDtor; 164 } 165}; 166 167/// CFGBaseDtor - Represents C++ object destructor implicitly generated for 168/// base object in destructor. 169class CFGBaseDtor : public CFGImplicitDtor { 170public: 171 CFGBaseDtor() {} 172 CFGBaseDtor(const CXXBaseSpecifier *BS) 173 : CFGImplicitDtor(BaseDtor, const_cast<CXXBaseSpecifier*>(BS), NULL) {} 174 175 const CXXBaseSpecifier *getBaseSpecifier() const { 176 return static_cast<const CXXBaseSpecifier*>(Data1.getPointer()); 177 } 178 179 static bool classof(const CFGElement *E) { 180 return E->getKind() == Dtor && E->getDtorKind() == BaseDtor; 181 } 182}; 183 184/// CFGMemberDtor - Represents C++ object destructor implicitly generated for 185/// member object in destructor. 186class CFGMemberDtor : public CFGImplicitDtor { 187public: 188 CFGMemberDtor() {} 189 CFGMemberDtor(FieldDecl *FD) 190 : CFGImplicitDtor(MemberDtor, FD, NULL) {} 191 192 FieldDecl *getFieldDecl() const { 193 return static_cast<FieldDecl*>(Data1.getPointer()); 194 } 195 196 static bool classof(const CFGElement *E) { 197 return E->getKind() == Dtor && E->getDtorKind() == MemberDtor; 198 } 199}; 200 201class CFGTemporaryDtor : public CFGImplicitDtor { 202public: 203 static bool classof(const CFGElement *E) { 204 return E->getKind() == Dtor && E->getDtorKind() == TemporaryDtor; 205 } 206}; 207 208/// CFGTerminator - Represents CFGBlock terminator statement. 209/// 210/// TemporaryDtorsBranch bit is set to true if the terminator marks a branch 211/// in control flow of destructors of temporaries. In this case terminator 212/// statement is the same statement that branches control flow in evaluation 213/// of matching full expression. 214class CFGTerminator { 215 llvm::PointerIntPair<Stmt *, 1> Data; 216public: 217 CFGTerminator() {} 218 CFGTerminator(Stmt *S, bool TemporaryDtorsBranch = false) 219 : Data(S, TemporaryDtorsBranch) {} 220 221 Stmt *getStmt() { return Data.getPointer(); } 222 const Stmt *getStmt() const { return Data.getPointer(); } 223 224 bool isTemporaryDtorsBranch() const { return Data.getInt(); } 225 226 operator Stmt *() { return getStmt(); } 227 operator const Stmt *() const { return getStmt(); } 228 229 Stmt *operator->() { return getStmt(); } 230 const Stmt *operator->() const { return getStmt(); } 231 232 Stmt &operator*() { return *getStmt(); } 233 const Stmt &operator*() const { return *getStmt(); } 234 235 operator bool() const { return getStmt(); } 236}; 237 238/// CFGBlock - Represents a single basic block in a source-level CFG. 239/// It consists of: 240/// 241/// (1) A set of statements/expressions (which may contain subexpressions). 242/// (2) A "terminator" statement (not in the set of statements). 243/// (3) A list of successors and predecessors. 244/// 245/// Terminator: The terminator represents the type of control-flow that occurs 246/// at the end of the basic block. The terminator is a Stmt* referring to an 247/// AST node that has control-flow: if-statements, breaks, loops, etc. 248/// If the control-flow is conditional, the condition expression will appear 249/// within the set of statements in the block (usually the last statement). 250/// 251/// Predecessors: the order in the set of predecessors is arbitrary. 252/// 253/// Successors: the order in the set of successors is NOT arbitrary. We 254/// currently have the following orderings based on the terminator: 255/// 256/// Terminator Successor Ordering 257/// ----------------------------------------------------- 258/// if Then Block; Else Block 259/// ? operator LHS expression; RHS expression 260/// &&, || expression that uses result of && or ||, RHS 261/// 262class CFGBlock { 263 class ElementList { 264 typedef BumpVector<CFGElement> ImplTy; 265 ImplTy Impl; 266 public: 267 ElementList(BumpVectorContext &C) : Impl(C, 4) {} 268 269 typedef std::reverse_iterator<ImplTy::iterator> iterator; 270 typedef std::reverse_iterator<ImplTy::const_iterator> const_iterator; 271 typedef ImplTy::iterator reverse_iterator; 272 typedef ImplTy::const_iterator const_reverse_iterator; 273 274 void push_back(CFGElement e, BumpVectorContext &C) { Impl.push_back(e, C); } 275 reverse_iterator insert(reverse_iterator I, size_t Cnt, CFGElement E, 276 BumpVectorContext& C) { 277 return Impl.insert(I, Cnt, E, C); 278 } 279 280 CFGElement front() const { return Impl.back(); } 281 CFGElement back() const { return Impl.front(); } 282 283 iterator begin() { return Impl.rbegin(); } 284 iterator end() { return Impl.rend(); } 285 const_iterator begin() const { return Impl.rbegin(); } 286 const_iterator end() const { return Impl.rend(); } 287 reverse_iterator rbegin() { return Impl.begin(); } 288 reverse_iterator rend() { return Impl.end(); } 289 const_reverse_iterator rbegin() const { return Impl.begin(); } 290 const_reverse_iterator rend() const { return Impl.end(); } 291 292 CFGElement operator[](size_t i) const { 293 assert(i < Impl.size()); 294 return Impl[Impl.size() - 1 - i]; 295 } 296 297 size_t size() const { return Impl.size(); } 298 bool empty() const { return Impl.empty(); } 299 }; 300 301 /// Stmts - The set of statements in the basic block. 302 ElementList Elements; 303 304 /// Label - An (optional) label that prefixes the executable 305 /// statements in the block. When this variable is non-NULL, it is 306 /// either an instance of LabelStmt, SwitchCase or CXXCatchStmt. 307 Stmt *Label; 308 309 /// Terminator - The terminator for a basic block that 310 /// indicates the type of control-flow that occurs between a block 311 /// and its successors. 312 CFGTerminator Terminator; 313 314 /// LoopTarget - Some blocks are used to represent the "loop edge" to 315 /// the start of a loop from within the loop body. This Stmt* will be 316 /// refer to the loop statement for such blocks (and be null otherwise). 317 const Stmt *LoopTarget; 318 319 /// BlockID - A numerical ID assigned to a CFGBlock during construction 320 /// of the CFG. 321 unsigned BlockID; 322 323 /// Predecessors/Successors - Keep track of the predecessor / successor 324 /// CFG blocks. 325 typedef BumpVector<CFGBlock*> AdjacentBlocks; 326 AdjacentBlocks Preds; 327 AdjacentBlocks Succs; 328 329public: 330 explicit CFGBlock(unsigned blockid, BumpVectorContext &C) 331 : Elements(C), Label(NULL), Terminator(NULL), LoopTarget(NULL), 332 BlockID(blockid), Preds(C, 1), Succs(C, 1) {} 333 ~CFGBlock() {} 334 335 // Statement iterators 336 typedef ElementList::iterator iterator; 337 typedef ElementList::const_iterator const_iterator; 338 typedef ElementList::reverse_iterator reverse_iterator; 339 typedef ElementList::const_reverse_iterator const_reverse_iterator; 340 341 CFGElement front() const { return Elements.front(); } 342 CFGElement back() const { return Elements.back(); } 343 344 iterator begin() { return Elements.begin(); } 345 iterator end() { return Elements.end(); } 346 const_iterator begin() const { return Elements.begin(); } 347 const_iterator end() const { return Elements.end(); } 348 349 reverse_iterator rbegin() { return Elements.rbegin(); } 350 reverse_iterator rend() { return Elements.rend(); } 351 const_reverse_iterator rbegin() const { return Elements.rbegin(); } 352 const_reverse_iterator rend() const { return Elements.rend(); } 353 354 unsigned size() const { return Elements.size(); } 355 bool empty() const { return Elements.empty(); } 356 357 CFGElement operator[](size_t i) const { return Elements[i]; } 358 359 // CFG iterators 360 typedef AdjacentBlocks::iterator pred_iterator; 361 typedef AdjacentBlocks::const_iterator const_pred_iterator; 362 typedef AdjacentBlocks::reverse_iterator pred_reverse_iterator; 363 typedef AdjacentBlocks::const_reverse_iterator const_pred_reverse_iterator; 364 365 typedef AdjacentBlocks::iterator succ_iterator; 366 typedef AdjacentBlocks::const_iterator const_succ_iterator; 367 typedef AdjacentBlocks::reverse_iterator succ_reverse_iterator; 368 typedef AdjacentBlocks::const_reverse_iterator const_succ_reverse_iterator; 369 370 pred_iterator pred_begin() { return Preds.begin(); } 371 pred_iterator pred_end() { return Preds.end(); } 372 const_pred_iterator pred_begin() const { return Preds.begin(); } 373 const_pred_iterator pred_end() const { return Preds.end(); } 374 375 pred_reverse_iterator pred_rbegin() { return Preds.rbegin(); } 376 pred_reverse_iterator pred_rend() { return Preds.rend(); } 377 const_pred_reverse_iterator pred_rbegin() const { return Preds.rbegin(); } 378 const_pred_reverse_iterator pred_rend() const { return Preds.rend(); } 379 380 succ_iterator succ_begin() { return Succs.begin(); } 381 succ_iterator succ_end() { return Succs.end(); } 382 const_succ_iterator succ_begin() const { return Succs.begin(); } 383 const_succ_iterator succ_end() const { return Succs.end(); } 384 385 succ_reverse_iterator succ_rbegin() { return Succs.rbegin(); } 386 succ_reverse_iterator succ_rend() { return Succs.rend(); } 387 const_succ_reverse_iterator succ_rbegin() const { return Succs.rbegin(); } 388 const_succ_reverse_iterator succ_rend() const { return Succs.rend(); } 389 390 unsigned succ_size() const { return Succs.size(); } 391 bool succ_empty() const { return Succs.empty(); } 392 393 unsigned pred_size() const { return Preds.size(); } 394 bool pred_empty() const { return Preds.empty(); } 395 396 397 class FilterOptions { 398 public: 399 FilterOptions() { 400 IgnoreDefaultsWithCoveredEnums = 0; 401 } 402 403 unsigned IgnoreDefaultsWithCoveredEnums : 1; 404 }; 405 406 static bool FilterEdge(const FilterOptions &F, const CFGBlock *Src, 407 const CFGBlock *Dst); 408 409 template <typename IMPL, bool IsPred> 410 class FilteredCFGBlockIterator { 411 private: 412 IMPL I, E; 413 const FilterOptions F; 414 const CFGBlock *From; 415 public: 416 explicit FilteredCFGBlockIterator(const IMPL &i, const IMPL &e, 417 const CFGBlock *from, 418 const FilterOptions &f) 419 : I(i), E(e), F(f), From(from) {} 420 421 bool hasMore() const { return I != E; } 422 423 FilteredCFGBlockIterator &operator++() { 424 do { ++I; } while (hasMore() && Filter(*I)); 425 return *this; 426 } 427 428 const CFGBlock *operator*() const { return *I; } 429 private: 430 bool Filter(const CFGBlock *To) { 431 return IsPred ? FilterEdge(F, To, From) : FilterEdge(F, From, To); 432 } 433 }; 434 435 typedef FilteredCFGBlockIterator<const_pred_iterator, true> 436 filtered_pred_iterator; 437 438 typedef FilteredCFGBlockIterator<const_succ_iterator, false> 439 filtered_succ_iterator; 440 441 filtered_pred_iterator filtered_pred_start_end(const FilterOptions &f) const { 442 return filtered_pred_iterator(pred_begin(), pred_end(), this, f); 443 } 444 445 filtered_succ_iterator filtered_succ_start_end(const FilterOptions &f) const { 446 return filtered_succ_iterator(succ_begin(), succ_end(), this, f); 447 } 448 449 // Manipulation of block contents 450 451 void setTerminator(Stmt* Statement) { Terminator = Statement; } 452 void setLabel(Stmt* Statement) { Label = Statement; } 453 void setLoopTarget(const Stmt *loopTarget) { LoopTarget = loopTarget; } 454 455 CFGTerminator getTerminator() { return Terminator; } 456 const CFGTerminator getTerminator() const { return Terminator; } 457 458 Stmt* getTerminatorCondition(); 459 460 const Stmt* getTerminatorCondition() const { 461 return const_cast<CFGBlock*>(this)->getTerminatorCondition(); 462 } 463 464 const Stmt *getLoopTarget() const { return LoopTarget; } 465 466 bool hasBinaryBranchTerminator() const; 467 468 Stmt* getLabel() { return Label; } 469 const Stmt* getLabel() const { return Label; } 470 471 unsigned getBlockID() const { return BlockID; } 472 473 void dump(const CFG *cfg, const LangOptions &LO) const; 474 void print(llvm::raw_ostream &OS, const CFG* cfg, const LangOptions &LO) const; 475 void printTerminator(llvm::raw_ostream &OS, const LangOptions &LO) const; 476 477 void addSuccessor(CFGBlock* Block, BumpVectorContext &C) { 478 if (Block) 479 Block->Preds.push_back(this, C); 480 Succs.push_back(Block, C); 481 } 482 483 void appendStmt(Stmt* Statement, BumpVectorContext &C, bool asLValue) { 484 Elements.push_back(CFGStmt(Statement, asLValue), C); 485 } 486 487 void appendInitializer(CXXBaseOrMemberInitializer *I, BumpVectorContext& C) { 488 Elements.push_back(CFGInitializer(I), C); 489 } 490 491 void appendBaseDtor(const CXXBaseSpecifier *BS, BumpVectorContext &C) { 492 Elements.push_back(CFGBaseDtor(BS), C); 493 } 494 495 void appendMemberDtor(FieldDecl *FD, BumpVectorContext &C) { 496 Elements.push_back(CFGMemberDtor(FD), C); 497 } 498 499 // Destructors must be inserted in reversed order. So insertion is in two 500 // steps. First we prepare space for some number of elements, then we insert 501 // the elements beginning at the last position in prepared space. 502 iterator beginAutomaticObjDtorsInsert(iterator I, size_t Cnt, 503 BumpVectorContext& C) { 504 return iterator(Elements.insert(I.base(), Cnt, CFGElement(), C)); 505 } 506 iterator insertAutomaticObjDtor(iterator I, VarDecl* VD, Stmt* S) { 507 *I = CFGAutomaticObjDtor(VD, S); 508 return ++I; 509 } 510}; 511 512/// CFG - Represents a source-level, intra-procedural CFG that represents the 513/// control-flow of a Stmt. The Stmt can represent an entire function body, 514/// or a single expression. A CFG will always contain one empty block that 515/// represents the Exit point of the CFG. A CFG will also contain a designated 516/// Entry block. The CFG solely represents control-flow; it consists of 517/// CFGBlocks which are simply containers of Stmt*'s in the AST the CFG 518/// was constructed from. 519class CFG { 520public: 521 //===--------------------------------------------------------------------===// 522 // CFG Construction & Manipulation. 523 //===--------------------------------------------------------------------===// 524 525 class BuildOptions { 526 public: 527 bool PruneTriviallyFalseEdges:1; 528 bool AddEHEdges:1; 529 bool AddInitializers:1; 530 bool AddImplicitDtors:1; 531 532 BuildOptions() 533 : PruneTriviallyFalseEdges(true) 534 , AddEHEdges(false) 535 , AddInitializers(false) 536 , AddImplicitDtors(false) {} 537 }; 538 539 /// buildCFG - Builds a CFG from an AST. The responsibility to free the 540 /// constructed CFG belongs to the caller. 541 static CFG* buildCFG(const Decl *D, Stmt* AST, ASTContext *C, 542 BuildOptions BO = BuildOptions()); 543 544 /// createBlock - Create a new block in the CFG. The CFG owns the block; 545 /// the caller should not directly free it. 546 CFGBlock* createBlock(); 547 548 /// setEntry - Set the entry block of the CFG. This is typically used 549 /// only during CFG construction. Most CFG clients expect that the 550 /// entry block has no predecessors and contains no statements. 551 void setEntry(CFGBlock *B) { Entry = B; } 552 553 /// setIndirectGotoBlock - Set the block used for indirect goto jumps. 554 /// This is typically used only during CFG construction. 555 void setIndirectGotoBlock(CFGBlock* B) { IndirectGotoBlock = B; } 556 557 //===--------------------------------------------------------------------===// 558 // Block Iterators 559 //===--------------------------------------------------------------------===// 560 561 typedef BumpVector<CFGBlock*> CFGBlockListTy; 562 typedef CFGBlockListTy::iterator iterator; 563 typedef CFGBlockListTy::const_iterator const_iterator; 564 typedef std::reverse_iterator<iterator> reverse_iterator; 565 typedef std::reverse_iterator<const_iterator> const_reverse_iterator; 566 567 CFGBlock& front() { return *Blocks.front(); } 568 CFGBlock& back() { return *Blocks.back(); } 569 570 iterator begin() { return Blocks.begin(); } 571 iterator end() { return Blocks.end(); } 572 const_iterator begin() const { return Blocks.begin(); } 573 const_iterator end() const { return Blocks.end(); } 574 575 reverse_iterator rbegin() { return Blocks.rbegin(); } 576 reverse_iterator rend() { return Blocks.rend(); } 577 const_reverse_iterator rbegin() const { return Blocks.rbegin(); } 578 const_reverse_iterator rend() const { return Blocks.rend(); } 579 580 CFGBlock& getEntry() { return *Entry; } 581 const CFGBlock& getEntry() const { return *Entry; } 582 CFGBlock& getExit() { return *Exit; } 583 const CFGBlock& getExit() const { return *Exit; } 584 585 CFGBlock* getIndirectGotoBlock() { return IndirectGotoBlock; } 586 const CFGBlock* getIndirectGotoBlock() const { return IndirectGotoBlock; } 587 588 //===--------------------------------------------------------------------===// 589 // Member templates useful for various batch operations over CFGs. 590 //===--------------------------------------------------------------------===// 591 592 template <typename CALLBACK> 593 void VisitBlockStmts(CALLBACK& O) const { 594 for (const_iterator I=begin(), E=end(); I != E; ++I) 595 for (CFGBlock::const_iterator BI=(*I)->begin(), BE=(*I)->end(); 596 BI != BE; ++BI) { 597 if (CFGStmt S = BI->getAs<CFGStmt>()) 598 O(S); 599 } 600 } 601 602 //===--------------------------------------------------------------------===// 603 // CFG Introspection. 604 //===--------------------------------------------------------------------===// 605 606 struct BlkExprNumTy { 607 const signed Idx; 608 explicit BlkExprNumTy(signed idx) : Idx(idx) {} 609 explicit BlkExprNumTy() : Idx(-1) {} 610 operator bool() const { return Idx >= 0; } 611 operator unsigned() const { assert(Idx >=0); return (unsigned) Idx; } 612 }; 613 614 bool isBlkExpr(const Stmt* S) { return getBlkExprNum(S); } 615 BlkExprNumTy getBlkExprNum(const Stmt* S); 616 unsigned getNumBlkExprs(); 617 618 /// getNumBlockIDs - Returns the total number of BlockIDs allocated (which 619 /// start at 0). 620 unsigned getNumBlockIDs() const { return NumBlockIDs; } 621 622 //===--------------------------------------------------------------------===// 623 // CFG Debugging: Pretty-Printing and Visualization. 624 //===--------------------------------------------------------------------===// 625 626 void viewCFG(const LangOptions &LO) const; 627 void print(llvm::raw_ostream& OS, const LangOptions &LO) const; 628 void dump(const LangOptions &LO) const; 629 630 //===--------------------------------------------------------------------===// 631 // Internal: constructors and data. 632 //===--------------------------------------------------------------------===// 633 634 CFG() : Entry(NULL), Exit(NULL), IndirectGotoBlock(NULL), NumBlockIDs(0), 635 BlkExprMap(NULL), Blocks(BlkBVC, 10) {} 636 637 ~CFG(); 638 639 llvm::BumpPtrAllocator& getAllocator() { 640 return BlkBVC.getAllocator(); 641 } 642 643 BumpVectorContext &getBumpVectorContext() { 644 return BlkBVC; 645 } 646 647private: 648 CFGBlock* Entry; 649 CFGBlock* Exit; 650 CFGBlock* IndirectGotoBlock; // Special block to contain collective dispatch 651 // for indirect gotos 652 unsigned NumBlockIDs; 653 654 // BlkExprMap - An opaque pointer to prevent inclusion of DenseMap.h. 655 // It represents a map from Expr* to integers to record the set of 656 // block-level expressions and their "statement number" in the CFG. 657 void* BlkExprMap; 658 659 BumpVectorContext BlkBVC; 660 661 CFGBlockListTy Blocks; 662 663}; 664} // end namespace clang 665 666//===----------------------------------------------------------------------===// 667// GraphTraits specializations for CFG basic block graphs (source-level CFGs) 668//===----------------------------------------------------------------------===// 669 670namespace llvm { 671 672/// Implement simplify_type for CFGTerminator, so that we can dyn_cast from 673/// CFGTerminator to a specific Stmt class. 674template <> struct simplify_type<const ::clang::CFGTerminator> { 675 typedef const ::clang::Stmt *SimpleType; 676 static SimpleType getSimplifiedValue(const ::clang::CFGTerminator &Val) { 677 return Val.getStmt(); 678 } 679}; 680 681template <> struct simplify_type< ::clang::CFGTerminator> { 682 typedef ::clang::Stmt *SimpleType; 683 static SimpleType getSimplifiedValue(const ::clang::CFGTerminator &Val) { 684 return const_cast<SimpleType>(Val.getStmt()); 685 } 686}; 687 688// Traits for: CFGBlock 689 690template <> struct GraphTraits< ::clang::CFGBlock* > { 691 typedef ::clang::CFGBlock NodeType; 692 typedef ::clang::CFGBlock::succ_iterator ChildIteratorType; 693 694 static NodeType* getEntryNode(::clang::CFGBlock* BB) 695 { return BB; } 696 697 static inline ChildIteratorType child_begin(NodeType* N) 698 { return N->succ_begin(); } 699 700 static inline ChildIteratorType child_end(NodeType* N) 701 { return N->succ_end(); } 702}; 703 704template <> struct GraphTraits< const ::clang::CFGBlock* > { 705 typedef const ::clang::CFGBlock NodeType; 706 typedef ::clang::CFGBlock::const_succ_iterator ChildIteratorType; 707 708 static NodeType* getEntryNode(const clang::CFGBlock* BB) 709 { return BB; } 710 711 static inline ChildIteratorType child_begin(NodeType* N) 712 { return N->succ_begin(); } 713 714 static inline ChildIteratorType child_end(NodeType* N) 715 { return N->succ_end(); } 716}; 717 718template <> struct GraphTraits<Inverse<const ::clang::CFGBlock*> > { 719 typedef const ::clang::CFGBlock NodeType; 720 typedef ::clang::CFGBlock::const_pred_iterator ChildIteratorType; 721 722 static NodeType *getEntryNode(Inverse<const ::clang::CFGBlock*> G) 723 { return G.Graph; } 724 725 static inline ChildIteratorType child_begin(NodeType* N) 726 { return N->pred_begin(); } 727 728 static inline ChildIteratorType child_end(NodeType* N) 729 { return N->pred_end(); } 730}; 731 732// Traits for: CFG 733 734template <> struct GraphTraits< ::clang::CFG* > 735 : public GraphTraits< ::clang::CFGBlock* > { 736 737 typedef ::clang::CFG::iterator nodes_iterator; 738 739 static NodeType *getEntryNode(::clang::CFG* F) { return &F->getEntry(); } 740 static nodes_iterator nodes_begin(::clang::CFG* F) { return F->begin(); } 741 static nodes_iterator nodes_end(::clang::CFG* F) { return F->end(); } 742}; 743 744template <> struct GraphTraits<const ::clang::CFG* > 745 : public GraphTraits<const ::clang::CFGBlock* > { 746 747 typedef ::clang::CFG::const_iterator nodes_iterator; 748 749 static NodeType *getEntryNode( const ::clang::CFG* F) { 750 return &F->getEntry(); 751 } 752 static nodes_iterator nodes_begin( const ::clang::CFG* F) { 753 return F->begin(); 754 } 755 static nodes_iterator nodes_end( const ::clang::CFG* F) { 756 return F->end(); 757 } 758}; 759 760template <> struct GraphTraits<Inverse<const ::clang::CFG*> > 761 : public GraphTraits<Inverse<const ::clang::CFGBlock*> > { 762 763 typedef ::clang::CFG::const_iterator nodes_iterator; 764 765 static NodeType *getEntryNode(const ::clang::CFG* F) { return &F->getExit(); } 766 static nodes_iterator nodes_begin(const ::clang::CFG* F) { return F->begin();} 767 static nodes_iterator nodes_end(const ::clang::CFG* F) { return F->end(); } 768}; 769} // end llvm namespace 770#endif 771