CFG.h revision 200fbc877d50da9e53b9aa272b70ca3538ce3a66
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#include <iterator> 26 27namespace llvm { 28 class raw_ostream; 29} 30 31namespace clang { 32 class Decl; 33 class Stmt; 34 class Expr; 35 class FieldDecl; 36 class VarDecl; 37 class CXXCtorInitializer; 38 class CXXBaseSpecifier; 39 class CXXBindTemporaryExpr; 40 class CFG; 41 class PrinterHelper; 42 class LangOptions; 43 class ASTContext; 44 45/// CFGElement - Represents a top-level expression in a basic block. 46class CFGElement { 47public: 48 enum Kind { 49 // main kind 50 Statement, 51 Initializer, 52 ImplicitDtor, 53 // dtor kind 54 AutomaticObjectDtor, 55 BaseDtor, 56 MemberDtor, 57 TemporaryDtor, 58 DTOR_BEGIN = AutomaticObjectDtor 59 }; 60 61protected: 62 // The int bits are used to mark the main kind. 63 llvm::PointerIntPair<void *, 2> Data1; 64 // The int bits are used to mark the dtor kind. 65 llvm::PointerIntPair<void *, 2> Data2; 66 67 CFGElement(void *Ptr, unsigned Int) : Data1(Ptr, Int) {} 68 CFGElement(void *Ptr1, unsigned Int1, void *Ptr2, unsigned Int2) 69 : Data1(Ptr1, Int1), Data2(Ptr2, Int2) {} 70 71public: 72 CFGElement() {} 73 74 Kind getKind() const { return static_cast<Kind>(Data1.getInt()); } 75 76 Kind getDtorKind() const { 77 assert(getKind() == ImplicitDtor); 78 return static_cast<Kind>(Data2.getInt() + DTOR_BEGIN); 79 } 80 81 bool isValid() const { return Data1.getPointer(); } 82 83 operator bool() const { return isValid(); } 84 85 template<class ElemTy> ElemTy getAs() const { 86 if (llvm::isa<ElemTy>(this)) 87 return *static_cast<const ElemTy*>(this); 88 return ElemTy(); 89 } 90 91 static bool classof(const CFGElement *E) { return true; } 92}; 93 94class CFGStmt : public CFGElement { 95public: 96 CFGStmt() {} 97 CFGStmt(Stmt *S) : CFGElement(S, 0) {} 98 99 Stmt *getStmt() const { return static_cast<Stmt *>(Data1.getPointer()); } 100 101 operator Stmt*() const { return getStmt(); } 102 103 static bool classof(const CFGElement *E) { 104 return E->getKind() == Statement; 105 } 106}; 107 108/// CFGInitializer - Represents C++ base or member initializer from 109/// constructor's initialization list. 110class CFGInitializer : public CFGElement { 111public: 112 CFGInitializer() {} 113 CFGInitializer(CXXCtorInitializer* I) 114 : CFGElement(I, Initializer) {} 115 116 CXXCtorInitializer* getInitializer() const { 117 return static_cast<CXXCtorInitializer*>(Data1.getPointer()); 118 } 119 operator CXXCtorInitializer*() const { return getInitializer(); } 120 121 static bool classof(const CFGElement *E) { 122 return E->getKind() == Initializer; 123 } 124}; 125 126/// CFGImplicitDtor - Represents C++ object destructor implicitly generated 127/// by compiler on various occasions. 128class CFGImplicitDtor : public CFGElement { 129protected: 130 CFGImplicitDtor(unsigned K, void* P, void* S) 131 : CFGElement(P, ImplicitDtor, S, K - DTOR_BEGIN) {} 132 133public: 134 CFGImplicitDtor() {} 135 136 static bool classof(const CFGElement *E) { 137 return E->getKind() == ImplicitDtor; 138 } 139}; 140 141/// CFGAutomaticObjDtor - Represents C++ object destructor implicitly generated 142/// for automatic object or temporary bound to const reference at the point 143/// of leaving its local scope. 144class CFGAutomaticObjDtor: public CFGImplicitDtor { 145public: 146 CFGAutomaticObjDtor() {} 147 CFGAutomaticObjDtor(VarDecl* VD, Stmt* S) 148 : CFGImplicitDtor(AutomaticObjectDtor, VD, S) {} 149 150 VarDecl* getVarDecl() const { 151 return static_cast<VarDecl*>(Data1.getPointer()); 152 } 153 154 // Get statement end of which triggered the destructor call. 155 Stmt* getTriggerStmt() const { 156 return static_cast<Stmt*>(Data2.getPointer()); 157 } 158 159 static bool classof(const CFGElement *E) { 160 return E->getKind() == ImplicitDtor && 161 E->getDtorKind() == AutomaticObjectDtor; 162 } 163}; 164 165/// CFGBaseDtor - Represents C++ object destructor implicitly generated for 166/// base object in destructor. 167class CFGBaseDtor : public CFGImplicitDtor { 168public: 169 CFGBaseDtor() {} 170 CFGBaseDtor(const CXXBaseSpecifier *BS) 171 : CFGImplicitDtor(BaseDtor, const_cast<CXXBaseSpecifier*>(BS), NULL) {} 172 173 const CXXBaseSpecifier *getBaseSpecifier() const { 174 return static_cast<const CXXBaseSpecifier*>(Data1.getPointer()); 175 } 176 177 static bool classof(const CFGElement *E) { 178 return E->getKind() == ImplicitDtor && E->getDtorKind() == BaseDtor; 179 } 180}; 181 182/// CFGMemberDtor - Represents C++ object destructor implicitly generated for 183/// member object in destructor. 184class CFGMemberDtor : public CFGImplicitDtor { 185public: 186 CFGMemberDtor() {} 187 CFGMemberDtor(FieldDecl *FD) 188 : CFGImplicitDtor(MemberDtor, FD, NULL) {} 189 190 FieldDecl *getFieldDecl() const { 191 return static_cast<FieldDecl*>(Data1.getPointer()); 192 } 193 194 static bool classof(const CFGElement *E) { 195 return E->getKind() == ImplicitDtor && E->getDtorKind() == MemberDtor; 196 } 197}; 198 199/// CFGTemporaryDtor - Represents C++ object destructor implicitly generated 200/// at the end of full expression for temporary object. 201class CFGTemporaryDtor : public CFGImplicitDtor { 202public: 203 CFGTemporaryDtor() {} 204 CFGTemporaryDtor(CXXBindTemporaryExpr *E) 205 : CFGImplicitDtor(TemporaryDtor, E, NULL) {} 206 207 CXXBindTemporaryExpr *getBindTemporaryExpr() const { 208 return static_cast<CXXBindTemporaryExpr *>(Data1.getPointer()); 209 } 210 211 static bool classof(const CFGElement *E) { 212 return E->getKind() == ImplicitDtor && E->getDtorKind() == TemporaryDtor; 213 } 214}; 215 216/// CFGTerminator - Represents CFGBlock terminator statement. 217/// 218/// TemporaryDtorsBranch bit is set to true if the terminator marks a branch 219/// in control flow of destructors of temporaries. In this case terminator 220/// statement is the same statement that branches control flow in evaluation 221/// of matching full expression. 222class CFGTerminator { 223 llvm::PointerIntPair<Stmt *, 1> Data; 224public: 225 CFGTerminator() {} 226 CFGTerminator(Stmt *S, bool TemporaryDtorsBranch = false) 227 : Data(S, TemporaryDtorsBranch) {} 228 229 Stmt *getStmt() { return Data.getPointer(); } 230 const Stmt *getStmt() const { return Data.getPointer(); } 231 232 bool isTemporaryDtorsBranch() const { return Data.getInt(); } 233 234 operator Stmt *() { return getStmt(); } 235 operator const Stmt *() const { return getStmt(); } 236 237 Stmt *operator->() { return getStmt(); } 238 const Stmt *operator->() const { return getStmt(); } 239 240 Stmt &operator*() { return *getStmt(); } 241 const Stmt &operator*() const { return *getStmt(); } 242 243 operator bool() const { return getStmt(); } 244}; 245 246/// CFGBlock - Represents a single basic block in a source-level CFG. 247/// It consists of: 248/// 249/// (1) A set of statements/expressions (which may contain subexpressions). 250/// (2) A "terminator" statement (not in the set of statements). 251/// (3) A list of successors and predecessors. 252/// 253/// Terminator: The terminator represents the type of control-flow that occurs 254/// at the end of the basic block. The terminator is a Stmt* referring to an 255/// AST node that has control-flow: if-statements, breaks, loops, etc. 256/// If the control-flow is conditional, the condition expression will appear 257/// within the set of statements in the block (usually the last statement). 258/// 259/// Predecessors: the order in the set of predecessors is arbitrary. 260/// 261/// Successors: the order in the set of successors is NOT arbitrary. We 262/// currently have the following orderings based on the terminator: 263/// 264/// Terminator Successor Ordering 265/// ----------------------------------------------------- 266/// if Then Block; Else Block 267/// ? operator LHS expression; RHS expression 268/// &&, || expression that uses result of && or ||, RHS 269/// 270class CFGBlock { 271 class ElementList { 272 typedef BumpVector<CFGElement> ImplTy; 273 ImplTy Impl; 274 public: 275 ElementList(BumpVectorContext &C) : Impl(C, 4) {} 276 277 typedef std::reverse_iterator<ImplTy::iterator> iterator; 278 typedef std::reverse_iterator<ImplTy::const_iterator> const_iterator; 279 typedef ImplTy::iterator reverse_iterator; 280 typedef ImplTy::const_iterator const_reverse_iterator; 281 282 void push_back(CFGElement e, BumpVectorContext &C) { Impl.push_back(e, C); } 283 reverse_iterator insert(reverse_iterator I, size_t Cnt, CFGElement E, 284 BumpVectorContext& C) { 285 return Impl.insert(I, Cnt, E, C); 286 } 287 288 CFGElement front() const { return Impl.back(); } 289 CFGElement back() const { return Impl.front(); } 290 291 iterator begin() { return Impl.rbegin(); } 292 iterator end() { return Impl.rend(); } 293 const_iterator begin() const { return Impl.rbegin(); } 294 const_iterator end() const { return Impl.rend(); } 295 reverse_iterator rbegin() { return Impl.begin(); } 296 reverse_iterator rend() { return Impl.end(); } 297 const_reverse_iterator rbegin() const { return Impl.begin(); } 298 const_reverse_iterator rend() const { return Impl.end(); } 299 300 CFGElement operator[](size_t i) const { 301 assert(i < Impl.size()); 302 return Impl[Impl.size() - 1 - i]; 303 } 304 305 size_t size() const { return Impl.size(); } 306 bool empty() const { return Impl.empty(); } 307 }; 308 309 /// Stmts - The set of statements in the basic block. 310 ElementList Elements; 311 312 /// Label - An (optional) label that prefixes the executable 313 /// statements in the block. When this variable is non-NULL, it is 314 /// either an instance of LabelStmt, SwitchCase or CXXCatchStmt. 315 Stmt *Label; 316 317 /// Terminator - The terminator for a basic block that 318 /// indicates the type of control-flow that occurs between a block 319 /// and its successors. 320 CFGTerminator Terminator; 321 322 /// LoopTarget - Some blocks are used to represent the "loop edge" to 323 /// the start of a loop from within the loop body. This Stmt* will be 324 /// refer to the loop statement for such blocks (and be null otherwise). 325 const Stmt *LoopTarget; 326 327 /// BlockID - A numerical ID assigned to a CFGBlock during construction 328 /// of the CFG. 329 unsigned BlockID; 330 331 /// Predecessors/Successors - Keep track of the predecessor / successor 332 /// CFG blocks. 333 typedef BumpVector<CFGBlock*> AdjacentBlocks; 334 AdjacentBlocks Preds; 335 AdjacentBlocks Succs; 336 337public: 338 explicit CFGBlock(unsigned blockid, BumpVectorContext &C) 339 : Elements(C), Label(NULL), Terminator(NULL), LoopTarget(NULL), 340 BlockID(blockid), Preds(C, 1), Succs(C, 1) {} 341 ~CFGBlock() {} 342 343 // Statement iterators 344 typedef ElementList::iterator iterator; 345 typedef ElementList::const_iterator const_iterator; 346 typedef ElementList::reverse_iterator reverse_iterator; 347 typedef ElementList::const_reverse_iterator const_reverse_iterator; 348 349 CFGElement front() const { return Elements.front(); } 350 CFGElement back() const { return Elements.back(); } 351 352 iterator begin() { return Elements.begin(); } 353 iterator end() { return Elements.end(); } 354 const_iterator begin() const { return Elements.begin(); } 355 const_iterator end() const { return Elements.end(); } 356 357 reverse_iterator rbegin() { return Elements.rbegin(); } 358 reverse_iterator rend() { return Elements.rend(); } 359 const_reverse_iterator rbegin() const { return Elements.rbegin(); } 360 const_reverse_iterator rend() const { return Elements.rend(); } 361 362 unsigned size() const { return Elements.size(); } 363 bool empty() const { return Elements.empty(); } 364 365 CFGElement operator[](size_t i) const { return Elements[i]; } 366 367 // CFG iterators 368 typedef AdjacentBlocks::iterator pred_iterator; 369 typedef AdjacentBlocks::const_iterator const_pred_iterator; 370 typedef AdjacentBlocks::reverse_iterator pred_reverse_iterator; 371 typedef AdjacentBlocks::const_reverse_iterator const_pred_reverse_iterator; 372 373 typedef AdjacentBlocks::iterator succ_iterator; 374 typedef AdjacentBlocks::const_iterator const_succ_iterator; 375 typedef AdjacentBlocks::reverse_iterator succ_reverse_iterator; 376 typedef AdjacentBlocks::const_reverse_iterator const_succ_reverse_iterator; 377 378 pred_iterator pred_begin() { return Preds.begin(); } 379 pred_iterator pred_end() { return Preds.end(); } 380 const_pred_iterator pred_begin() const { return Preds.begin(); } 381 const_pred_iterator pred_end() const { return Preds.end(); } 382 383 pred_reverse_iterator pred_rbegin() { return Preds.rbegin(); } 384 pred_reverse_iterator pred_rend() { return Preds.rend(); } 385 const_pred_reverse_iterator pred_rbegin() const { return Preds.rbegin(); } 386 const_pred_reverse_iterator pred_rend() const { return Preds.rend(); } 387 388 succ_iterator succ_begin() { return Succs.begin(); } 389 succ_iterator succ_end() { return Succs.end(); } 390 const_succ_iterator succ_begin() const { return Succs.begin(); } 391 const_succ_iterator succ_end() const { return Succs.end(); } 392 393 succ_reverse_iterator succ_rbegin() { return Succs.rbegin(); } 394 succ_reverse_iterator succ_rend() { return Succs.rend(); } 395 const_succ_reverse_iterator succ_rbegin() const { return Succs.rbegin(); } 396 const_succ_reverse_iterator succ_rend() const { return Succs.rend(); } 397 398 unsigned succ_size() const { return Succs.size(); } 399 bool succ_empty() const { return Succs.empty(); } 400 401 unsigned pred_size() const { return Preds.size(); } 402 bool pred_empty() const { return Preds.empty(); } 403 404 405 class FilterOptions { 406 public: 407 FilterOptions() { 408 IgnoreDefaultsWithCoveredEnums = 0; 409 } 410 411 unsigned IgnoreDefaultsWithCoveredEnums : 1; 412 }; 413 414 static bool FilterEdge(const FilterOptions &F, const CFGBlock *Src, 415 const CFGBlock *Dst); 416 417 template <typename IMPL, bool IsPred> 418 class FilteredCFGBlockIterator { 419 private: 420 IMPL I, E; 421 const FilterOptions F; 422 const CFGBlock *From; 423 public: 424 explicit FilteredCFGBlockIterator(const IMPL &i, const IMPL &e, 425 const CFGBlock *from, 426 const FilterOptions &f) 427 : I(i), E(e), F(f), From(from) {} 428 429 bool hasMore() const { return I != E; } 430 431 FilteredCFGBlockIterator &operator++() { 432 do { ++I; } while (hasMore() && Filter(*I)); 433 return *this; 434 } 435 436 const CFGBlock *operator*() const { return *I; } 437 private: 438 bool Filter(const CFGBlock *To) { 439 return IsPred ? FilterEdge(F, To, From) : FilterEdge(F, From, To); 440 } 441 }; 442 443 typedef FilteredCFGBlockIterator<const_pred_iterator, true> 444 filtered_pred_iterator; 445 446 typedef FilteredCFGBlockIterator<const_succ_iterator, false> 447 filtered_succ_iterator; 448 449 filtered_pred_iterator filtered_pred_start_end(const FilterOptions &f) const { 450 return filtered_pred_iterator(pred_begin(), pred_end(), this, f); 451 } 452 453 filtered_succ_iterator filtered_succ_start_end(const FilterOptions &f) const { 454 return filtered_succ_iterator(succ_begin(), succ_end(), this, f); 455 } 456 457 // Manipulation of block contents 458 459 void setTerminator(Stmt* Statement) { Terminator = Statement; } 460 void setLabel(Stmt* Statement) { Label = Statement; } 461 void setLoopTarget(const Stmt *loopTarget) { LoopTarget = loopTarget; } 462 463 CFGTerminator getTerminator() { return Terminator; } 464 const CFGTerminator getTerminator() const { return Terminator; } 465 466 Stmt* getTerminatorCondition(); 467 468 const Stmt* getTerminatorCondition() const { 469 return const_cast<CFGBlock*>(this)->getTerminatorCondition(); 470 } 471 472 const Stmt *getLoopTarget() const { return LoopTarget; } 473 474 bool hasBinaryBranchTerminator() const; 475 476 Stmt* getLabel() { return Label; } 477 const Stmt* getLabel() const { return Label; } 478 479 unsigned getBlockID() const { return BlockID; } 480 481 void dump(const CFG *cfg, const LangOptions &LO) const; 482 void print(llvm::raw_ostream &OS, const CFG* cfg, const LangOptions &LO) const; 483 void printTerminator(llvm::raw_ostream &OS, const LangOptions &LO) const; 484 485 void addSuccessor(CFGBlock* Block, BumpVectorContext &C) { 486 if (Block) 487 Block->Preds.push_back(this, C); 488 Succs.push_back(Block, C); 489 } 490 491 void appendStmt(Stmt* statement, BumpVectorContext &C) { 492 Elements.push_back(CFGStmt(statement), C); 493 } 494 495 void appendInitializer(CXXCtorInitializer *initializer, 496 BumpVectorContext& C) { 497 Elements.push_back(CFGInitializer(initializer), C); 498 } 499 500 void appendBaseDtor(const CXXBaseSpecifier *BS, BumpVectorContext &C) { 501 Elements.push_back(CFGBaseDtor(BS), C); 502 } 503 504 void appendMemberDtor(FieldDecl *FD, BumpVectorContext &C) { 505 Elements.push_back(CFGMemberDtor(FD), C); 506 } 507 508 void appendTemporaryDtor(CXXBindTemporaryExpr *E, BumpVectorContext &C) { 509 Elements.push_back(CFGTemporaryDtor(E), C); 510 } 511 512 // Destructors must be inserted in reversed order. So insertion is in two 513 // steps. First we prepare space for some number of elements, then we insert 514 // the elements beginning at the last position in prepared space. 515 iterator beginAutomaticObjDtorsInsert(iterator I, size_t Cnt, 516 BumpVectorContext& C) { 517 return iterator(Elements.insert(I.base(), Cnt, CFGElement(), C)); 518 } 519 iterator insertAutomaticObjDtor(iterator I, VarDecl* VD, Stmt* S) { 520 *I = CFGAutomaticObjDtor(VD, S); 521 return ++I; 522 } 523}; 524 525/// CFG - Represents a source-level, intra-procedural CFG that represents the 526/// control-flow of a Stmt. The Stmt can represent an entire function body, 527/// or a single expression. A CFG will always contain one empty block that 528/// represents the Exit point of the CFG. A CFG will also contain a designated 529/// Entry block. The CFG solely represents control-flow; it consists of 530/// CFGBlocks which are simply containers of Stmt*'s in the AST the CFG 531/// was constructed from. 532class CFG { 533public: 534 //===--------------------------------------------------------------------===// 535 // CFG Construction & Manipulation. 536 //===--------------------------------------------------------------------===// 537 538 class BuildOptions { 539 public: 540 bool PruneTriviallyFalseEdges:1; 541 bool AddEHEdges:1; 542 bool AddInitializers:1; 543 bool AddImplicitDtors:1; 544 545 BuildOptions() 546 : PruneTriviallyFalseEdges(true) 547 , AddEHEdges(false) 548 , AddInitializers(false) 549 , AddImplicitDtors(false) {} 550 }; 551 552 /// buildCFG - Builds a CFG from an AST. The responsibility to free the 553 /// constructed CFG belongs to the caller. 554 static CFG* buildCFG(const Decl *D, Stmt* AST, ASTContext *C, 555 BuildOptions BO = BuildOptions()); 556 557 /// createBlock - Create a new block in the CFG. The CFG owns the block; 558 /// the caller should not directly free it. 559 CFGBlock* createBlock(); 560 561 /// setEntry - Set the entry block of the CFG. This is typically used 562 /// only during CFG construction. Most CFG clients expect that the 563 /// entry block has no predecessors and contains no statements. 564 void setEntry(CFGBlock *B) { Entry = B; } 565 566 /// setIndirectGotoBlock - Set the block used for indirect goto jumps. 567 /// This is typically used only during CFG construction. 568 void setIndirectGotoBlock(CFGBlock* B) { IndirectGotoBlock = B; } 569 570 //===--------------------------------------------------------------------===// 571 // Block Iterators 572 //===--------------------------------------------------------------------===// 573 574 typedef BumpVector<CFGBlock*> CFGBlockListTy; 575 typedef CFGBlockListTy::iterator iterator; 576 typedef CFGBlockListTy::const_iterator const_iterator; 577 typedef std::reverse_iterator<iterator> reverse_iterator; 578 typedef std::reverse_iterator<const_iterator> const_reverse_iterator; 579 580 CFGBlock& front() { return *Blocks.front(); } 581 CFGBlock& back() { return *Blocks.back(); } 582 583 iterator begin() { return Blocks.begin(); } 584 iterator end() { return Blocks.end(); } 585 const_iterator begin() const { return Blocks.begin(); } 586 const_iterator end() const { return Blocks.end(); } 587 588 reverse_iterator rbegin() { return Blocks.rbegin(); } 589 reverse_iterator rend() { return Blocks.rend(); } 590 const_reverse_iterator rbegin() const { return Blocks.rbegin(); } 591 const_reverse_iterator rend() const { return Blocks.rend(); } 592 593 CFGBlock& getEntry() { return *Entry; } 594 const CFGBlock& getEntry() const { return *Entry; } 595 CFGBlock& getExit() { return *Exit; } 596 const CFGBlock& getExit() const { return *Exit; } 597 598 CFGBlock* getIndirectGotoBlock() { return IndirectGotoBlock; } 599 const CFGBlock* getIndirectGotoBlock() const { return IndirectGotoBlock; } 600 601 //===--------------------------------------------------------------------===// 602 // Member templates useful for various batch operations over CFGs. 603 //===--------------------------------------------------------------------===// 604 605 template <typename CALLBACK> 606 void VisitBlockStmts(CALLBACK& O) const { 607 for (const_iterator I=begin(), E=end(); I != E; ++I) 608 for (CFGBlock::const_iterator BI=(*I)->begin(), BE=(*I)->end(); 609 BI != BE; ++BI) { 610 if (CFGStmt S = BI->getAs<CFGStmt>()) 611 O(S); 612 } 613 } 614 615 //===--------------------------------------------------------------------===// 616 // CFG Introspection. 617 //===--------------------------------------------------------------------===// 618 619 struct BlkExprNumTy { 620 const signed Idx; 621 explicit BlkExprNumTy(signed idx) : Idx(idx) {} 622 explicit BlkExprNumTy() : Idx(-1) {} 623 operator bool() const { return Idx >= 0; } 624 operator unsigned() const { assert(Idx >=0); return (unsigned) Idx; } 625 }; 626 627 bool isBlkExpr(const Stmt* S) { return getBlkExprNum(S); } 628 bool isBlkExpr(const Stmt *S) const { 629 return const_cast<CFG*>(this)->isBlkExpr(S); 630 } 631 BlkExprNumTy getBlkExprNum(const Stmt* S); 632 unsigned getNumBlkExprs(); 633 634 /// getNumBlockIDs - Returns the total number of BlockIDs allocated (which 635 /// start at 0). 636 unsigned getNumBlockIDs() const { return NumBlockIDs; } 637 638 //===--------------------------------------------------------------------===// 639 // CFG Debugging: Pretty-Printing and Visualization. 640 //===--------------------------------------------------------------------===// 641 642 void viewCFG(const LangOptions &LO) const; 643 void print(llvm::raw_ostream& OS, const LangOptions &LO) const; 644 void dump(const LangOptions &LO) const; 645 646 //===--------------------------------------------------------------------===// 647 // Internal: constructors and data. 648 //===--------------------------------------------------------------------===// 649 650 CFG() : Entry(NULL), Exit(NULL), IndirectGotoBlock(NULL), NumBlockIDs(0), 651 BlkExprMap(NULL), Blocks(BlkBVC, 10) {} 652 653 ~CFG(); 654 655 llvm::BumpPtrAllocator& getAllocator() { 656 return BlkBVC.getAllocator(); 657 } 658 659 BumpVectorContext &getBumpVectorContext() { 660 return BlkBVC; 661 } 662 663private: 664 CFGBlock* Entry; 665 CFGBlock* Exit; 666 CFGBlock* IndirectGotoBlock; // Special block to contain collective dispatch 667 // for indirect gotos 668 unsigned NumBlockIDs; 669 670 // BlkExprMap - An opaque pointer to prevent inclusion of DenseMap.h. 671 // It represents a map from Expr* to integers to record the set of 672 // block-level expressions and their "statement number" in the CFG. 673 void* BlkExprMap; 674 675 BumpVectorContext BlkBVC; 676 677 CFGBlockListTy Blocks; 678 679}; 680} // end namespace clang 681 682//===----------------------------------------------------------------------===// 683// GraphTraits specializations for CFG basic block graphs (source-level CFGs) 684//===----------------------------------------------------------------------===// 685 686namespace llvm { 687 688/// Implement simplify_type for CFGTerminator, so that we can dyn_cast from 689/// CFGTerminator to a specific Stmt class. 690template <> struct simplify_type<const ::clang::CFGTerminator> { 691 typedef const ::clang::Stmt *SimpleType; 692 static SimpleType getSimplifiedValue(const ::clang::CFGTerminator &Val) { 693 return Val.getStmt(); 694 } 695}; 696 697template <> struct simplify_type< ::clang::CFGTerminator> { 698 typedef ::clang::Stmt *SimpleType; 699 static SimpleType getSimplifiedValue(const ::clang::CFGTerminator &Val) { 700 return const_cast<SimpleType>(Val.getStmt()); 701 } 702}; 703 704// Traits for: CFGBlock 705 706template <> struct GraphTraits< ::clang::CFGBlock* > { 707 typedef ::clang::CFGBlock NodeType; 708 typedef ::clang::CFGBlock::succ_iterator ChildIteratorType; 709 710 static NodeType* getEntryNode(::clang::CFGBlock* BB) 711 { return BB; } 712 713 static inline ChildIteratorType child_begin(NodeType* N) 714 { return N->succ_begin(); } 715 716 static inline ChildIteratorType child_end(NodeType* N) 717 { return N->succ_end(); } 718}; 719 720template <> struct GraphTraits< const ::clang::CFGBlock* > { 721 typedef const ::clang::CFGBlock NodeType; 722 typedef ::clang::CFGBlock::const_succ_iterator ChildIteratorType; 723 724 static NodeType* getEntryNode(const clang::CFGBlock* BB) 725 { return BB; } 726 727 static inline ChildIteratorType child_begin(NodeType* N) 728 { return N->succ_begin(); } 729 730 static inline ChildIteratorType child_end(NodeType* N) 731 { return N->succ_end(); } 732}; 733 734template <> struct GraphTraits<Inverse<const ::clang::CFGBlock*> > { 735 typedef const ::clang::CFGBlock NodeType; 736 typedef ::clang::CFGBlock::const_pred_iterator ChildIteratorType; 737 738 static NodeType *getEntryNode(Inverse<const ::clang::CFGBlock*> G) 739 { return G.Graph; } 740 741 static inline ChildIteratorType child_begin(NodeType* N) 742 { return N->pred_begin(); } 743 744 static inline ChildIteratorType child_end(NodeType* N) 745 { return N->pred_end(); } 746}; 747 748// Traits for: CFG 749 750template <> struct GraphTraits< ::clang::CFG* > 751 : public GraphTraits< ::clang::CFGBlock* > { 752 753 typedef ::clang::CFG::iterator nodes_iterator; 754 755 static NodeType *getEntryNode(::clang::CFG* F) { return &F->getEntry(); } 756 static nodes_iterator nodes_begin(::clang::CFG* F) { return F->begin(); } 757 static nodes_iterator nodes_end(::clang::CFG* F) { return F->end(); } 758}; 759 760template <> struct GraphTraits<const ::clang::CFG* > 761 : public GraphTraits<const ::clang::CFGBlock* > { 762 763 typedef ::clang::CFG::const_iterator nodes_iterator; 764 765 static NodeType *getEntryNode( const ::clang::CFG* F) { 766 return &F->getEntry(); 767 } 768 static nodes_iterator nodes_begin( const ::clang::CFG* F) { 769 return F->begin(); 770 } 771 static nodes_iterator nodes_end( const ::clang::CFG* F) { 772 return F->end(); 773 } 774}; 775 776template <> struct GraphTraits<Inverse<const ::clang::CFG*> > 777 : public GraphTraits<Inverse<const ::clang::CFGBlock*> > { 778 779 typedef ::clang::CFG::const_iterator nodes_iterator; 780 781 static NodeType *getEntryNode(const ::clang::CFG* F) { return &F->getExit(); } 782 static nodes_iterator nodes_begin(const ::clang::CFG* F) { return F->begin();} 783 static nodes_iterator nodes_end(const ::clang::CFG* F) { return F->end(); } 784}; 785} // end llvm namespace 786#endif 787