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Diffstat (limited to 'include/clang/Analysis/CFG.h')
| -rw-r--r-- | include/clang/Analysis/CFG.h | 1113 |
1 files changed, 0 insertions, 1113 deletions
diff --git a/include/clang/Analysis/CFG.h b/include/clang/Analysis/CFG.h deleted file mode 100644 index 293990c..0000000 --- a/include/clang/Analysis/CFG.h +++ /dev/null @@ -1,1113 +0,0 @@ -//===--- CFG.h - Classes for representing and building CFGs------*- C++ -*-===// -// -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// This file defines the CFG and CFGBuilder classes for representing and -// building Control-Flow Graphs (CFGs) from ASTs. -// -//===----------------------------------------------------------------------===// - -#ifndef LLVM_CLANG_ANALYSIS_CFG_H -#define LLVM_CLANG_ANALYSIS_CFG_H - -#include "clang/AST/Stmt.h" -#include "clang/Analysis/Support/BumpVector.h" -#include "clang/Basic/SourceLocation.h" -#include "llvm/ADT/DenseMap.h" -#include "llvm/ADT/GraphTraits.h" -#include "llvm/ADT/Optional.h" -#include "llvm/ADT/PointerIntPair.h" -#include "llvm/Support/Allocator.h" -#include "llvm/Support/Casting.h" -#include "llvm/Support/raw_ostream.h" -#include <bitset> -#include <cassert> -#include <iterator> -#include <memory> - -namespace clang { - class CXXDestructorDecl; - class Decl; - class Stmt; - class Expr; - class FieldDecl; - class VarDecl; - class CXXCtorInitializer; - class CXXBaseSpecifier; - class CXXBindTemporaryExpr; - class CFG; - class PrinterHelper; - class LangOptions; - class ASTContext; - class CXXRecordDecl; - class CXXDeleteExpr; - class CXXNewExpr; - class BinaryOperator; - -/// CFGElement - Represents a top-level expression in a basic block. -class CFGElement { -public: - enum Kind { - // main kind - Statement, - Initializer, - NewAllocator, - // dtor kind - AutomaticObjectDtor, - DeleteDtor, - BaseDtor, - MemberDtor, - TemporaryDtor, - DTOR_BEGIN = AutomaticObjectDtor, - DTOR_END = TemporaryDtor - }; - -protected: - // The int bits are used to mark the kind. - llvm::PointerIntPair<void *, 2> Data1; - llvm::PointerIntPair<void *, 2> Data2; - - CFGElement(Kind kind, const void *Ptr1, const void *Ptr2 = nullptr) - : Data1(const_cast<void*>(Ptr1), ((unsigned) kind) & 0x3), - Data2(const_cast<void*>(Ptr2), (((unsigned) kind) >> 2) & 0x3) { - assert(getKind() == kind); - } - - CFGElement() {} -public: - - /// \brief Convert to the specified CFGElement type, asserting that this - /// CFGElement is of the desired type. - template<typename T> - T castAs() const { - assert(T::isKind(*this)); - T t; - CFGElement& e = t; - e = *this; - return t; - } - - /// \brief Convert to the specified CFGElement type, returning None if this - /// CFGElement is not of the desired type. - template<typename T> - Optional<T> getAs() const { - if (!T::isKind(*this)) - return None; - T t; - CFGElement& e = t; - e = *this; - return t; - } - - Kind getKind() const { - unsigned x = Data2.getInt(); - x <<= 2; - x |= Data1.getInt(); - return (Kind) x; - } -}; - -class CFGStmt : public CFGElement { -public: - CFGStmt(Stmt *S) : CFGElement(Statement, S) {} - - const Stmt *getStmt() const { - return static_cast<const Stmt *>(Data1.getPointer()); - } - -private: - friend class CFGElement; - CFGStmt() {} - static bool isKind(const CFGElement &E) { - return E.getKind() == Statement; - } -}; - -/// CFGInitializer - Represents C++ base or member initializer from -/// constructor's initialization list. -class CFGInitializer : public CFGElement { -public: - CFGInitializer(CXXCtorInitializer *initializer) - : CFGElement(Initializer, initializer) {} - - CXXCtorInitializer* getInitializer() const { - return static_cast<CXXCtorInitializer*>(Data1.getPointer()); - } - -private: - friend class CFGElement; - CFGInitializer() {} - static bool isKind(const CFGElement &E) { - return E.getKind() == Initializer; - } -}; - -/// CFGNewAllocator - Represents C++ allocator call. -class CFGNewAllocator : public CFGElement { -public: - explicit CFGNewAllocator(const CXXNewExpr *S) - : CFGElement(NewAllocator, S) {} - - // Get the new expression. - const CXXNewExpr *getAllocatorExpr() const { - return static_cast<CXXNewExpr *>(Data1.getPointer()); - } - -private: - friend class CFGElement; - CFGNewAllocator() {} - static bool isKind(const CFGElement &elem) { - return elem.getKind() == NewAllocator; - } -}; - -/// CFGImplicitDtor - Represents C++ object destructor implicitly generated -/// by compiler on various occasions. -class CFGImplicitDtor : public CFGElement { -protected: - CFGImplicitDtor() {} - CFGImplicitDtor(Kind kind, const void *data1, const void *data2 = nullptr) - : CFGElement(kind, data1, data2) { - assert(kind >= DTOR_BEGIN && kind <= DTOR_END); - } - -public: - const CXXDestructorDecl *getDestructorDecl(ASTContext &astContext) const; - bool isNoReturn(ASTContext &astContext) const; - -private: - friend class CFGElement; - static bool isKind(const CFGElement &E) { - Kind kind = E.getKind(); - return kind >= DTOR_BEGIN && kind <= DTOR_END; - } -}; - -/// CFGAutomaticObjDtor - Represents C++ object destructor implicitly generated -/// for automatic object or temporary bound to const reference at the point -/// of leaving its local scope. -class CFGAutomaticObjDtor: public CFGImplicitDtor { -public: - CFGAutomaticObjDtor(const VarDecl *var, const Stmt *stmt) - : CFGImplicitDtor(AutomaticObjectDtor, var, stmt) {} - - const VarDecl *getVarDecl() const { - return static_cast<VarDecl*>(Data1.getPointer()); - } - - // Get statement end of which triggered the destructor call. - const Stmt *getTriggerStmt() const { - return static_cast<Stmt*>(Data2.getPointer()); - } - -private: - friend class CFGElement; - CFGAutomaticObjDtor() {} - static bool isKind(const CFGElement &elem) { - return elem.getKind() == AutomaticObjectDtor; - } -}; - -/// CFGDeleteDtor - Represents C++ object destructor generated -/// from a call to delete. -class CFGDeleteDtor : public CFGImplicitDtor { -public: - CFGDeleteDtor(const CXXRecordDecl *RD, const CXXDeleteExpr *DE) - : CFGImplicitDtor(DeleteDtor, RD, DE) {} - - const CXXRecordDecl *getCXXRecordDecl() const { - return static_cast<CXXRecordDecl*>(Data1.getPointer()); - } - - // Get Delete expression which triggered the destructor call. - const CXXDeleteExpr *getDeleteExpr() const { - return static_cast<CXXDeleteExpr *>(Data2.getPointer()); - } - -private: - friend class CFGElement; - CFGDeleteDtor() {} - static bool isKind(const CFGElement &elem) { - return elem.getKind() == DeleteDtor; - } -}; - -/// CFGBaseDtor - Represents C++ object destructor implicitly generated for -/// base object in destructor. -class CFGBaseDtor : public CFGImplicitDtor { -public: - CFGBaseDtor(const CXXBaseSpecifier *base) - : CFGImplicitDtor(BaseDtor, base) {} - - const CXXBaseSpecifier *getBaseSpecifier() const { - return static_cast<const CXXBaseSpecifier*>(Data1.getPointer()); - } - -private: - friend class CFGElement; - CFGBaseDtor() {} - static bool isKind(const CFGElement &E) { - return E.getKind() == BaseDtor; - } -}; - -/// CFGMemberDtor - Represents C++ object destructor implicitly generated for -/// member object in destructor. -class CFGMemberDtor : public CFGImplicitDtor { -public: - CFGMemberDtor(const FieldDecl *field) - : CFGImplicitDtor(MemberDtor, field, nullptr) {} - - const FieldDecl *getFieldDecl() const { - return static_cast<const FieldDecl*>(Data1.getPointer()); - } - -private: - friend class CFGElement; - CFGMemberDtor() {} - static bool isKind(const CFGElement &E) { - return E.getKind() == MemberDtor; - } -}; - -/// CFGTemporaryDtor - Represents C++ object destructor implicitly generated -/// at the end of full expression for temporary object. -class CFGTemporaryDtor : public CFGImplicitDtor { -public: - CFGTemporaryDtor(CXXBindTemporaryExpr *expr) - : CFGImplicitDtor(TemporaryDtor, expr, nullptr) {} - - const CXXBindTemporaryExpr *getBindTemporaryExpr() const { - return static_cast<const CXXBindTemporaryExpr *>(Data1.getPointer()); - } - -private: - friend class CFGElement; - CFGTemporaryDtor() {} - static bool isKind(const CFGElement &E) { - return E.getKind() == TemporaryDtor; - } -}; - -/// CFGTerminator - Represents CFGBlock terminator statement. -/// -/// TemporaryDtorsBranch bit is set to true if the terminator marks a branch -/// in control flow of destructors of temporaries. In this case terminator -/// statement is the same statement that branches control flow in evaluation -/// of matching full expression. -class CFGTerminator { - llvm::PointerIntPair<Stmt *, 1> Data; -public: - CFGTerminator() {} - CFGTerminator(Stmt *S, bool TemporaryDtorsBranch = false) - : Data(S, TemporaryDtorsBranch) {} - - Stmt *getStmt() { return Data.getPointer(); } - const Stmt *getStmt() const { return Data.getPointer(); } - - bool isTemporaryDtorsBranch() const { return Data.getInt(); } - - operator Stmt *() { return getStmt(); } - operator const Stmt *() const { return getStmt(); } - - Stmt *operator->() { return getStmt(); } - const Stmt *operator->() const { return getStmt(); } - - Stmt &operator*() { return *getStmt(); } - const Stmt &operator*() const { return *getStmt(); } - - explicit operator bool() const { return getStmt(); } -}; - -/// CFGBlock - Represents a single basic block in a source-level CFG. -/// It consists of: -/// -/// (1) A set of statements/expressions (which may contain subexpressions). -/// (2) A "terminator" statement (not in the set of statements). -/// (3) A list of successors and predecessors. -/// -/// Terminator: The terminator represents the type of control-flow that occurs -/// at the end of the basic block. The terminator is a Stmt* referring to an -/// AST node that has control-flow: if-statements, breaks, loops, etc. -/// If the control-flow is conditional, the condition expression will appear -/// within the set of statements in the block (usually the last statement). -/// -/// Predecessors: the order in the set of predecessors is arbitrary. -/// -/// Successors: the order in the set of successors is NOT arbitrary. We -/// currently have the following orderings based on the terminator: -/// -/// Terminator Successor Ordering -/// ----------------------------------------------------- -/// if Then Block; Else Block -/// ? operator LHS expression; RHS expression -/// &&, || expression that uses result of && or ||, RHS -/// -/// But note that any of that may be NULL in case of optimized-out edges. -/// -class CFGBlock { - class ElementList { - typedef BumpVector<CFGElement> ImplTy; - ImplTy Impl; - public: - ElementList(BumpVectorContext &C) : Impl(C, 4) {} - - typedef std::reverse_iterator<ImplTy::iterator> iterator; - typedef std::reverse_iterator<ImplTy::const_iterator> const_iterator; - typedef ImplTy::iterator reverse_iterator; - typedef ImplTy::const_iterator const_reverse_iterator; - typedef ImplTy::const_reference const_reference; - - void push_back(CFGElement e, BumpVectorContext &C) { Impl.push_back(e, C); } - reverse_iterator insert(reverse_iterator I, size_t Cnt, CFGElement E, - BumpVectorContext &C) { - return Impl.insert(I, Cnt, E, C); - } - - const_reference front() const { return Impl.back(); } - const_reference back() const { return Impl.front(); } - - iterator begin() { return Impl.rbegin(); } - iterator end() { return Impl.rend(); } - const_iterator begin() const { return Impl.rbegin(); } - const_iterator end() const { return Impl.rend(); } - reverse_iterator rbegin() { return Impl.begin(); } - reverse_iterator rend() { return Impl.end(); } - const_reverse_iterator rbegin() const { return Impl.begin(); } - const_reverse_iterator rend() const { return Impl.end(); } - - CFGElement operator[](size_t i) const { - assert(i < Impl.size()); - return Impl[Impl.size() - 1 - i]; - } - - size_t size() const { return Impl.size(); } - bool empty() const { return Impl.empty(); } - }; - - /// Stmts - The set of statements in the basic block. - ElementList Elements; - - /// Label - An (optional) label that prefixes the executable - /// statements in the block. When this variable is non-NULL, it is - /// either an instance of LabelStmt, SwitchCase or CXXCatchStmt. - Stmt *Label; - - /// Terminator - The terminator for a basic block that - /// indicates the type of control-flow that occurs between a block - /// and its successors. - CFGTerminator Terminator; - - /// LoopTarget - Some blocks are used to represent the "loop edge" to - /// the start of a loop from within the loop body. This Stmt* will be - /// refer to the loop statement for such blocks (and be null otherwise). - const Stmt *LoopTarget; - - /// BlockID - A numerical ID assigned to a CFGBlock during construction - /// of the CFG. - unsigned BlockID; - -public: - /// This class represents a potential adjacent block in the CFG. It encodes - /// whether or not the block is actually reachable, or can be proved to be - /// trivially unreachable. For some cases it allows one to encode scenarios - /// where a block was substituted because the original (now alternate) block - /// is unreachable. - class AdjacentBlock { - enum Kind { - AB_Normal, - AB_Unreachable, - AB_Alternate - }; - - CFGBlock *ReachableBlock; - llvm::PointerIntPair<CFGBlock*, 2> UnreachableBlock; - - public: - /// Construct an AdjacentBlock with a possibly unreachable block. - AdjacentBlock(CFGBlock *B, bool IsReachable); - - /// Construct an AdjacentBlock with a reachable block and an alternate - /// unreachable block. - AdjacentBlock(CFGBlock *B, CFGBlock *AlternateBlock); - - /// Get the reachable block, if one exists. - CFGBlock *getReachableBlock() const { - return ReachableBlock; - } - - /// Get the potentially unreachable block. - CFGBlock *getPossiblyUnreachableBlock() const { - return UnreachableBlock.getPointer(); - } - - /// Provide an implicit conversion to CFGBlock* so that - /// AdjacentBlock can be substituted for CFGBlock*. - operator CFGBlock*() const { - return getReachableBlock(); - } - - CFGBlock& operator *() const { - return *getReachableBlock(); - } - - CFGBlock* operator ->() const { - return getReachableBlock(); - } - - bool isReachable() const { - Kind K = (Kind) UnreachableBlock.getInt(); - return K == AB_Normal || K == AB_Alternate; - } - }; - -private: - /// Predecessors/Successors - Keep track of the predecessor / successor - /// CFG blocks. - typedef BumpVector<AdjacentBlock> AdjacentBlocks; - AdjacentBlocks Preds; - AdjacentBlocks Succs; - - /// NoReturn - This bit is set when the basic block contains a function call - /// or implicit destructor that is attributed as 'noreturn'. In that case, - /// control cannot technically ever proceed past this block. All such blocks - /// will have a single immediate successor: the exit block. This allows them - /// to be easily reached from the exit block and using this bit quickly - /// recognized without scanning the contents of the block. - /// - /// Optimization Note: This bit could be profitably folded with Terminator's - /// storage if the memory usage of CFGBlock becomes an issue. - unsigned HasNoReturnElement : 1; - - /// Parent - The parent CFG that owns this CFGBlock. - CFG *Parent; - -public: - explicit CFGBlock(unsigned blockid, BumpVectorContext &C, CFG *parent) - : Elements(C), Label(nullptr), Terminator(nullptr), LoopTarget(nullptr), - BlockID(blockid), Preds(C, 1), Succs(C, 1), HasNoReturnElement(false), - Parent(parent) {} - - // Statement iterators - typedef ElementList::iterator iterator; - typedef ElementList::const_iterator const_iterator; - typedef ElementList::reverse_iterator reverse_iterator; - typedef ElementList::const_reverse_iterator const_reverse_iterator; - - CFGElement front() const { return Elements.front(); } - CFGElement back() const { return Elements.back(); } - - iterator begin() { return Elements.begin(); } - iterator end() { return Elements.end(); } - const_iterator begin() const { return Elements.begin(); } - const_iterator end() const { return Elements.end(); } - - reverse_iterator rbegin() { return Elements.rbegin(); } - reverse_iterator rend() { return Elements.rend(); } - const_reverse_iterator rbegin() const { return Elements.rbegin(); } - const_reverse_iterator rend() const { return Elements.rend(); } - - unsigned size() const { return Elements.size(); } - bool empty() const { return Elements.empty(); } - - CFGElement operator[](size_t i) const { return Elements[i]; } - - // CFG iterators - typedef AdjacentBlocks::iterator pred_iterator; - typedef AdjacentBlocks::const_iterator const_pred_iterator; - typedef AdjacentBlocks::reverse_iterator pred_reverse_iterator; - typedef AdjacentBlocks::const_reverse_iterator const_pred_reverse_iterator; - - typedef AdjacentBlocks::iterator succ_iterator; - typedef AdjacentBlocks::const_iterator const_succ_iterator; - typedef AdjacentBlocks::reverse_iterator succ_reverse_iterator; - typedef AdjacentBlocks::const_reverse_iterator const_succ_reverse_iterator; - - pred_iterator pred_begin() { return Preds.begin(); } - pred_iterator pred_end() { return Preds.end(); } - const_pred_iterator pred_begin() const { return Preds.begin(); } - const_pred_iterator pred_end() const { return Preds.end(); } - - pred_reverse_iterator pred_rbegin() { return Preds.rbegin(); } - pred_reverse_iterator pred_rend() { return Preds.rend(); } - const_pred_reverse_iterator pred_rbegin() const { return Preds.rbegin(); } - const_pred_reverse_iterator pred_rend() const { return Preds.rend(); } - - succ_iterator succ_begin() { return Succs.begin(); } - succ_iterator succ_end() { return Succs.end(); } - const_succ_iterator succ_begin() const { return Succs.begin(); } - const_succ_iterator succ_end() const { return Succs.end(); } - - succ_reverse_iterator succ_rbegin() { return Succs.rbegin(); } - succ_reverse_iterator succ_rend() { return Succs.rend(); } - const_succ_reverse_iterator succ_rbegin() const { return Succs.rbegin(); } - const_succ_reverse_iterator succ_rend() const { return Succs.rend(); } - - unsigned succ_size() const { return Succs.size(); } - bool succ_empty() const { return Succs.empty(); } - - unsigned pred_size() const { return Preds.size(); } - bool pred_empty() const { return Preds.empty(); } - - - class FilterOptions { - public: - FilterOptions() { - IgnoreNullPredecessors = 1; - IgnoreDefaultsWithCoveredEnums = 0; - } - - unsigned IgnoreNullPredecessors : 1; - unsigned IgnoreDefaultsWithCoveredEnums : 1; - }; - - static bool FilterEdge(const FilterOptions &F, const CFGBlock *Src, - const CFGBlock *Dst); - - template <typename IMPL, bool IsPred> - class FilteredCFGBlockIterator { - private: - IMPL I, E; - const FilterOptions F; - const CFGBlock *From; - public: - explicit FilteredCFGBlockIterator(const IMPL &i, const IMPL &e, - const CFGBlock *from, - const FilterOptions &f) - : I(i), E(e), F(f), From(from) { - while (hasMore() && Filter(*I)) - ++I; - } - - bool hasMore() const { return I != E; } - - FilteredCFGBlockIterator &operator++() { - do { ++I; } while (hasMore() && Filter(*I)); - return *this; - } - - const CFGBlock *operator*() const { return *I; } - private: - bool Filter(const CFGBlock *To) { - return IsPred ? FilterEdge(F, To, From) : FilterEdge(F, From, To); - } - }; - - typedef FilteredCFGBlockIterator<const_pred_iterator, true> - filtered_pred_iterator; - - typedef FilteredCFGBlockIterator<const_succ_iterator, false> - filtered_succ_iterator; - - filtered_pred_iterator filtered_pred_start_end(const FilterOptions &f) const { - return filtered_pred_iterator(pred_begin(), pred_end(), this, f); - } - - filtered_succ_iterator filtered_succ_start_end(const FilterOptions &f) const { - return filtered_succ_iterator(succ_begin(), succ_end(), this, f); - } - - // Manipulation of block contents - - void setTerminator(CFGTerminator Term) { Terminator = Term; } - void setLabel(Stmt *Statement) { Label = Statement; } - void setLoopTarget(const Stmt *loopTarget) { LoopTarget = loopTarget; } - void setHasNoReturnElement() { HasNoReturnElement = true; } - - CFGTerminator getTerminator() { return Terminator; } - const CFGTerminator getTerminator() const { return Terminator; } - - Stmt *getTerminatorCondition(bool StripParens = true); - - const Stmt *getTerminatorCondition(bool StripParens = true) const { - return const_cast<CFGBlock*>(this)->getTerminatorCondition(StripParens); - } - - const Stmt *getLoopTarget() const { return LoopTarget; } - - Stmt *getLabel() { return Label; } - const Stmt *getLabel() const { return Label; } - - bool hasNoReturnElement() const { return HasNoReturnElement; } - - unsigned getBlockID() const { return BlockID; } - - CFG *getParent() const { return Parent; } - - void dump() const; - - void dump(const CFG *cfg, const LangOptions &LO, bool ShowColors = false) const; - void print(raw_ostream &OS, const CFG* cfg, const LangOptions &LO, - bool ShowColors) const; - void printTerminator(raw_ostream &OS, const LangOptions &LO) const; - void printAsOperand(raw_ostream &OS, bool /*PrintType*/) { - OS << "BB#" << getBlockID(); - } - - /// Adds a (potentially unreachable) successor block to the current block. - void addSuccessor(AdjacentBlock Succ, BumpVectorContext &C); - - void appendStmt(Stmt *statement, BumpVectorContext &C) { - Elements.push_back(CFGStmt(statement), C); - } - - void appendInitializer(CXXCtorInitializer *initializer, - BumpVectorContext &C) { - Elements.push_back(CFGInitializer(initializer), C); - } - - void appendNewAllocator(CXXNewExpr *NE, - BumpVectorContext &C) { - Elements.push_back(CFGNewAllocator(NE), C); - } - - void appendBaseDtor(const CXXBaseSpecifier *BS, BumpVectorContext &C) { - Elements.push_back(CFGBaseDtor(BS), C); - } - - void appendMemberDtor(FieldDecl *FD, BumpVectorContext &C) { - Elements.push_back(CFGMemberDtor(FD), C); - } - - void appendTemporaryDtor(CXXBindTemporaryExpr *E, BumpVectorContext &C) { - Elements.push_back(CFGTemporaryDtor(E), C); - } - - void appendAutomaticObjDtor(VarDecl *VD, Stmt *S, BumpVectorContext &C) { - Elements.push_back(CFGAutomaticObjDtor(VD, S), C); - } - - void appendDeleteDtor(CXXRecordDecl *RD, CXXDeleteExpr *DE, BumpVectorContext &C) { - Elements.push_back(CFGDeleteDtor(RD, DE), C); - } - - // Destructors must be inserted in reversed order. So insertion is in two - // steps. First we prepare space for some number of elements, then we insert - // the elements beginning at the last position in prepared space. - iterator beginAutomaticObjDtorsInsert(iterator I, size_t Cnt, - BumpVectorContext &C) { - return iterator(Elements.insert(I.base(), Cnt, - CFGAutomaticObjDtor(nullptr, nullptr), C)); - } - iterator insertAutomaticObjDtor(iterator I, VarDecl *VD, Stmt *S) { - *I = CFGAutomaticObjDtor(VD, S); - return ++I; - } -}; - -/// \brief CFGCallback defines methods that should be called when a logical -/// operator error is found when building the CFG. -class CFGCallback { -public: - CFGCallback() {} - virtual void compareAlwaysTrue(const BinaryOperator *B, bool isAlwaysTrue) {} - virtual void compareBitwiseEquality(const BinaryOperator *B, - bool isAlwaysTrue) {} - virtual ~CFGCallback() {} -}; - -/// CFG - Represents a source-level, intra-procedural CFG that represents the -/// control-flow of a Stmt. The Stmt can represent an entire function body, -/// or a single expression. A CFG will always contain one empty block that -/// represents the Exit point of the CFG. A CFG will also contain a designated -/// Entry block. The CFG solely represents control-flow; it consists of -/// CFGBlocks which are simply containers of Stmt*'s in the AST the CFG -/// was constructed from. -class CFG { -public: - //===--------------------------------------------------------------------===// - // CFG Construction & Manipulation. - //===--------------------------------------------------------------------===// - - class BuildOptions { - std::bitset<Stmt::lastStmtConstant> alwaysAddMask; - public: - typedef llvm::DenseMap<const Stmt *, const CFGBlock*> ForcedBlkExprs; - ForcedBlkExprs **forcedBlkExprs; - CFGCallback *Observer; - bool PruneTriviallyFalseEdges; - bool AddEHEdges; - bool AddInitializers; - bool AddImplicitDtors; - bool AddTemporaryDtors; - bool AddStaticInitBranches; - bool AddCXXNewAllocator; - bool AddCXXDefaultInitExprInCtors; - - bool alwaysAdd(const Stmt *stmt) const { - return alwaysAddMask[stmt->getStmtClass()]; - } - - BuildOptions &setAlwaysAdd(Stmt::StmtClass stmtClass, bool val = true) { - alwaysAddMask[stmtClass] = val; - return *this; - } - - BuildOptions &setAllAlwaysAdd() { - alwaysAddMask.set(); - return *this; - } - - BuildOptions() - : forcedBlkExprs(nullptr), Observer(nullptr), - PruneTriviallyFalseEdges(true), AddEHEdges(false), - AddInitializers(false), AddImplicitDtors(false), - AddTemporaryDtors(false), AddStaticInitBranches(false), - AddCXXNewAllocator(false), AddCXXDefaultInitExprInCtors(false) {} - }; - - /// \brief Provides a custom implementation of the iterator class to have the - /// same interface as Function::iterator - iterator returns CFGBlock - /// (not a pointer to CFGBlock). - class graph_iterator { - public: - typedef CFGBlock value_type; - typedef value_type& reference; - typedef value_type* pointer; - typedef BumpVector<CFGBlock*>::iterator ImplTy; - - graph_iterator(const ImplTy &i) : I(i) {} - - bool operator==(const graph_iterator &X) const { return I == X.I; } - bool operator!=(const graph_iterator &X) const { return I != X.I; } - - reference operator*() const { return **I; } - pointer operator->() const { return *I; } - operator CFGBlock* () { return *I; } - - graph_iterator &operator++() { ++I; return *this; } - graph_iterator &operator--() { --I; return *this; } - - private: - ImplTy I; - }; - - class const_graph_iterator { - public: - typedef const CFGBlock value_type; - typedef value_type& reference; - typedef value_type* pointer; - typedef BumpVector<CFGBlock*>::const_iterator ImplTy; - - const_graph_iterator(const ImplTy &i) : I(i) {} - - bool operator==(const const_graph_iterator &X) const { return I == X.I; } - bool operator!=(const const_graph_iterator &X) const { return I != X.I; } - - reference operator*() const { return **I; } - pointer operator->() const { return *I; } - operator CFGBlock* () const { return *I; } - - const_graph_iterator &operator++() { ++I; return *this; } - const_graph_iterator &operator--() { --I; return *this; } - - private: - ImplTy I; - }; - - /// buildCFG - Builds a CFG from an AST. - static std::unique_ptr<CFG> buildCFG(const Decl *D, Stmt *AST, ASTContext *C, - const BuildOptions &BO); - - /// createBlock - Create a new block in the CFG. The CFG owns the block; - /// the caller should not directly free it. - CFGBlock *createBlock(); - - /// setEntry - Set the entry block of the CFG. This is typically used - /// only during CFG construction. Most CFG clients expect that the - /// entry block has no predecessors and contains no statements. - void setEntry(CFGBlock *B) { Entry = B; } - - /// setIndirectGotoBlock - Set the block used for indirect goto jumps. - /// This is typically used only during CFG construction. - void setIndirectGotoBlock(CFGBlock *B) { IndirectGotoBlock = B; } - - //===--------------------------------------------------------------------===// - // Block Iterators - //===--------------------------------------------------------------------===// - - typedef BumpVector<CFGBlock*> CFGBlockListTy; - typedef CFGBlockListTy::iterator iterator; - typedef CFGBlockListTy::const_iterator const_iterator; - typedef std::reverse_iterator<iterator> reverse_iterator; - typedef std::reverse_iterator<const_iterator> const_reverse_iterator; - - CFGBlock & front() { return *Blocks.front(); } - CFGBlock & back() { return *Blocks.back(); } - - iterator begin() { return Blocks.begin(); } - iterator end() { return Blocks.end(); } - const_iterator begin() const { return Blocks.begin(); } - const_iterator end() const { return Blocks.end(); } - - graph_iterator nodes_begin() { return graph_iterator(Blocks.begin()); } - graph_iterator nodes_end() { return graph_iterator(Blocks.end()); } - const_graph_iterator nodes_begin() const { - return const_graph_iterator(Blocks.begin()); - } - const_graph_iterator nodes_end() const { - return const_graph_iterator(Blocks.end()); - } - - reverse_iterator rbegin() { return Blocks.rbegin(); } - reverse_iterator rend() { return Blocks.rend(); } - const_reverse_iterator rbegin() const { return Blocks.rbegin(); } - const_reverse_iterator rend() const { return Blocks.rend(); } - - CFGBlock & getEntry() { return *Entry; } - const CFGBlock & getEntry() const { return *Entry; } - CFGBlock & getExit() { return *Exit; } - const CFGBlock & getExit() const { return *Exit; } - - CFGBlock * getIndirectGotoBlock() { return IndirectGotoBlock; } - const CFGBlock * getIndirectGotoBlock() const { return IndirectGotoBlock; } - - typedef std::vector<const CFGBlock*>::const_iterator try_block_iterator; - try_block_iterator try_blocks_begin() const { - return TryDispatchBlocks.begin(); - } - try_block_iterator try_blocks_end() const { - return TryDispatchBlocks.end(); - } - - void addTryDispatchBlock(const CFGBlock *block) { - TryDispatchBlocks.push_back(block); - } - - /// Records a synthetic DeclStmt and the DeclStmt it was constructed from. - /// - /// The CFG uses synthetic DeclStmts when a single AST DeclStmt contains - /// multiple decls. - void addSyntheticDeclStmt(const DeclStmt *Synthetic, - const DeclStmt *Source) { - assert(Synthetic->isSingleDecl() && "Can handle single declarations only"); - assert(Synthetic != Source && "Don't include original DeclStmts in map"); - assert(!SyntheticDeclStmts.count(Synthetic) && "Already in map"); - SyntheticDeclStmts[Synthetic] = Source; - } - - typedef llvm::DenseMap<const DeclStmt *, const DeclStmt *>::const_iterator - synthetic_stmt_iterator; - - /// Iterates over synthetic DeclStmts in the CFG. - /// - /// Each element is a (synthetic statement, source statement) pair. - /// - /// \sa addSyntheticDeclStmt - synthetic_stmt_iterator synthetic_stmt_begin() const { - return SyntheticDeclStmts.begin(); - } - - /// \sa synthetic_stmt_begin - synthetic_stmt_iterator synthetic_stmt_end() const { - return SyntheticDeclStmts.end(); - } - - //===--------------------------------------------------------------------===// - // Member templates useful for various batch operations over CFGs. - //===--------------------------------------------------------------------===// - - template <typename CALLBACK> - void VisitBlockStmts(CALLBACK& O) const { - for (const_iterator I=begin(), E=end(); I != E; ++I) - for (CFGBlock::const_iterator BI=(*I)->begin(), BE=(*I)->end(); - BI != BE; ++BI) { - if (Optional<CFGStmt> stmt = BI->getAs<CFGStmt>()) - O(const_cast<Stmt*>(stmt->getStmt())); - } - } - - //===--------------------------------------------------------------------===// - // CFG Introspection. - //===--------------------------------------------------------------------===// - - /// getNumBlockIDs - Returns the total number of BlockIDs allocated (which - /// start at 0). - unsigned getNumBlockIDs() const { return NumBlockIDs; } - - /// size - Return the total number of CFGBlocks within the CFG - /// This is simply a renaming of the getNumBlockIDs(). This is necessary - /// because the dominator implementation needs such an interface. - unsigned size() const { return NumBlockIDs; } - - //===--------------------------------------------------------------------===// - // CFG Debugging: Pretty-Printing and Visualization. - //===--------------------------------------------------------------------===// - - void viewCFG(const LangOptions &LO) const; - void print(raw_ostream &OS, const LangOptions &LO, bool ShowColors) const; - void dump(const LangOptions &LO, bool ShowColors) const; - - //===--------------------------------------------------------------------===// - // Internal: constructors and data. - //===--------------------------------------------------------------------===// - - CFG() - : Entry(nullptr), Exit(nullptr), IndirectGotoBlock(nullptr), NumBlockIDs(0), - Blocks(BlkBVC, 10) {} - - llvm::BumpPtrAllocator& getAllocator() { - return BlkBVC.getAllocator(); - } - - BumpVectorContext &getBumpVectorContext() { - return BlkBVC; - } - -private: - CFGBlock *Entry; - CFGBlock *Exit; - CFGBlock* IndirectGotoBlock; // Special block to contain collective dispatch - // for indirect gotos - unsigned NumBlockIDs; - - BumpVectorContext BlkBVC; - - CFGBlockListTy Blocks; - - /// C++ 'try' statements are modeled with an indirect dispatch block. - /// This is the collection of such blocks present in the CFG. - std::vector<const CFGBlock *> TryDispatchBlocks; - - /// Collects DeclStmts synthesized for this CFG and maps each one back to its - /// source DeclStmt. - llvm::DenseMap<const DeclStmt *, const DeclStmt *> SyntheticDeclStmts; -}; -} // end namespace clang - -//===----------------------------------------------------------------------===// -// GraphTraits specializations for CFG basic block graphs (source-level CFGs) -//===----------------------------------------------------------------------===// - -namespace llvm { - -/// Implement simplify_type for CFGTerminator, so that we can dyn_cast from -/// CFGTerminator to a specific Stmt class. -template <> struct simplify_type< ::clang::CFGTerminator> { - typedef ::clang::Stmt *SimpleType; - static SimpleType getSimplifiedValue(::clang::CFGTerminator Val) { - return Val.getStmt(); - } -}; - -// Traits for: CFGBlock - -template <> struct GraphTraits< ::clang::CFGBlock *> { - typedef ::clang::CFGBlock NodeType; - typedef ::clang::CFGBlock::succ_iterator ChildIteratorType; - - static NodeType* getEntryNode(::clang::CFGBlock *BB) - { return BB; } - - static inline ChildIteratorType child_begin(NodeType* N) - { return N->succ_begin(); } - - static inline ChildIteratorType child_end(NodeType* N) - { return N->succ_end(); } -}; - -template <> struct GraphTraits< const ::clang::CFGBlock *> { - typedef const ::clang::CFGBlock NodeType; - typedef ::clang::CFGBlock::const_succ_iterator ChildIteratorType; - - static NodeType* getEntryNode(const clang::CFGBlock *BB) - { return BB; } - - static inline ChildIteratorType child_begin(NodeType* N) - { return N->succ_begin(); } - - static inline ChildIteratorType child_end(NodeType* N) - { return N->succ_end(); } -}; - -template <> struct GraphTraits<Inverse< ::clang::CFGBlock*> > { - typedef ::clang::CFGBlock NodeType; - typedef ::clang::CFGBlock::const_pred_iterator ChildIteratorType; - - static NodeType *getEntryNode(Inverse< ::clang::CFGBlock*> G) - { return G.Graph; } - - static inline ChildIteratorType child_begin(NodeType* N) - { return N->pred_begin(); } - - static inline ChildIteratorType child_end(NodeType* N) - { return N->pred_end(); } -}; - -template <> struct GraphTraits<Inverse<const ::clang::CFGBlock*> > { - typedef const ::clang::CFGBlock NodeType; - typedef ::clang::CFGBlock::const_pred_iterator ChildIteratorType; - - static NodeType *getEntryNode(Inverse<const ::clang::CFGBlock*> G) - { return G.Graph; } - - static inline ChildIteratorType child_begin(NodeType* N) - { return N->pred_begin(); } - - static inline ChildIteratorType child_end(NodeType* N) - { return N->pred_end(); } -}; - -// Traits for: CFG - -template <> struct GraphTraits< ::clang::CFG* > - : public GraphTraits< ::clang::CFGBlock *> { - - typedef ::clang::CFG::graph_iterator nodes_iterator; - - static NodeType *getEntryNode(::clang::CFG* F) { return &F->getEntry(); } - static nodes_iterator nodes_begin(::clang::CFG* F) { return F->nodes_begin();} - static nodes_iterator nodes_end(::clang::CFG* F) { return F->nodes_end(); } - static unsigned size(::clang::CFG* F) { return F->size(); } -}; - -template <> struct GraphTraits<const ::clang::CFG* > - : public GraphTraits<const ::clang::CFGBlock *> { - - typedef ::clang::CFG::const_graph_iterator nodes_iterator; - - static NodeType *getEntryNode( const ::clang::CFG* F) { - return &F->getEntry(); - } - static nodes_iterator nodes_begin( const ::clang::CFG* F) { - return F->nodes_begin(); - } - static nodes_iterator nodes_end( const ::clang::CFG* F) { - return F->nodes_end(); - } - static unsigned size(const ::clang::CFG* F) { - return F->size(); - } -}; - -template <> struct GraphTraits<Inverse< ::clang::CFG*> > - : public GraphTraits<Inverse< ::clang::CFGBlock*> > { - - typedef ::clang::CFG::graph_iterator nodes_iterator; - - static NodeType *getEntryNode( ::clang::CFG* F) { return &F->getExit(); } - static nodes_iterator nodes_begin( ::clang::CFG* F) {return F->nodes_begin();} - static nodes_iterator nodes_end( ::clang::CFG* F) { return F->nodes_end(); } -}; - -template <> struct GraphTraits<Inverse<const ::clang::CFG*> > - : public GraphTraits<Inverse<const ::clang::CFGBlock*> > { - - typedef ::clang::CFG::const_graph_iterator nodes_iterator; - - static NodeType *getEntryNode(const ::clang::CFG* F) { return &F->getExit(); } - static nodes_iterator nodes_begin(const ::clang::CFG* F) { - return F->nodes_begin(); - } - static nodes_iterator nodes_end(const ::clang::CFG* F) { - return F->nodes_end(); - } -}; -} // end llvm namespace - -#endif // LLVM_CLANG_ANALYSIS_CFG_H |
