| //===- CFG.h - Process LLVM structures as graphs ----------------*- 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 specializations of GraphTraits that allow Function and |
| // BasicBlock graphs to be treated as proper graphs for generic algorithms. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_IR_CFG_H |
| #define LLVM_IR_CFG_H |
| |
| #include "llvm/ADT/GraphTraits.h" |
| #include "llvm/IR/Function.h" |
| #include "llvm/IR/InstrTypes.h" |
| |
| namespace llvm { |
| |
| //===----------------------------------------------------------------------===// |
| // BasicBlock pred_iterator definition |
| //===----------------------------------------------------------------------===// |
| |
| template <class Ptr, class USE_iterator> // Predecessor Iterator |
| class PredIterator : public std::iterator<std::forward_iterator_tag, |
| Ptr, ptrdiff_t, Ptr*, Ptr*> { |
| typedef std::iterator<std::forward_iterator_tag, Ptr, ptrdiff_t, Ptr*, |
| Ptr*> super; |
| typedef PredIterator<Ptr, USE_iterator> Self; |
| USE_iterator It; |
| |
| inline void advancePastNonTerminators() { |
| // Loop to ignore non-terminator uses (for example BlockAddresses). |
| while (!It.atEnd() && !isa<TerminatorInst>(*It)) |
| ++It; |
| } |
| |
| public: |
| typedef typename super::pointer pointer; |
| typedef typename super::reference reference; |
| |
| PredIterator() {} |
| explicit inline PredIterator(Ptr *bb) : It(bb->user_begin()) { |
| advancePastNonTerminators(); |
| } |
| inline PredIterator(Ptr *bb, bool) : It(bb->user_end()) {} |
| |
| inline bool operator==(const Self& x) const { return It == x.It; } |
| inline bool operator!=(const Self& x) const { return !operator==(x); } |
| |
| inline reference operator*() const { |
| assert(!It.atEnd() && "pred_iterator out of range!"); |
| return cast<TerminatorInst>(*It)->getParent(); |
| } |
| inline pointer *operator->() const { return &operator*(); } |
| |
| inline Self& operator++() { // Preincrement |
| assert(!It.atEnd() && "pred_iterator out of range!"); |
| ++It; advancePastNonTerminators(); |
| return *this; |
| } |
| |
| inline Self operator++(int) { // Postincrement |
| Self tmp = *this; ++*this; return tmp; |
| } |
| |
| /// getOperandNo - Return the operand number in the predecessor's |
| /// terminator of the successor. |
| unsigned getOperandNo() const { |
| return It.getOperandNo(); |
| } |
| |
| /// getUse - Return the operand Use in the predecessor's terminator |
| /// of the successor. |
| Use &getUse() const { |
| return It.getUse(); |
| } |
| }; |
| |
| typedef PredIterator<BasicBlock, Value::user_iterator> pred_iterator; |
| typedef PredIterator<const BasicBlock, |
| Value::const_user_iterator> const_pred_iterator; |
| |
| inline pred_iterator pred_begin(BasicBlock *BB) { return pred_iterator(BB); } |
| inline const_pred_iterator pred_begin(const BasicBlock *BB) { |
| return const_pred_iterator(BB); |
| } |
| inline pred_iterator pred_end(BasicBlock *BB) { return pred_iterator(BB, true);} |
| inline const_pred_iterator pred_end(const BasicBlock *BB) { |
| return const_pred_iterator(BB, true); |
| } |
| |
| |
| |
| //===----------------------------------------------------------------------===// |
| // BasicBlock succ_iterator definition |
| //===----------------------------------------------------------------------===// |
| |
| template <class Term_, class BB_> // Successor Iterator |
| class SuccIterator : public std::iterator<std::random_access_iterator_tag, BB_, |
| int, BB_ *, BB_ *> { |
| typedef std::iterator<std::random_access_iterator_tag, BB_, int, BB_ *, BB_ *> |
| super; |
| |
| public: |
| typedef typename super::pointer pointer; |
| typedef typename super::reference reference; |
| |
| private: |
| const Term_ Term; |
| unsigned idx; |
| typedef SuccIterator<Term_, BB_> Self; |
| |
| inline bool index_is_valid(int idx) { |
| return idx >= 0 && (unsigned) idx < Term->getNumSuccessors(); |
| } |
| |
| /// \brief Proxy object to allow write access in operator[] |
| class SuccessorProxy { |
| Self it; |
| |
| public: |
| explicit SuccessorProxy(const Self &it) : it(it) {} |
| |
| SuccessorProxy &operator=(SuccessorProxy r) { |
| *this = reference(r); |
| return *this; |
| } |
| |
| SuccessorProxy &operator=(reference r) { |
| it.Term->setSuccessor(it.idx, r); |
| return *this; |
| } |
| |
| operator reference() const { return *it; } |
| }; |
| |
| public: |
| explicit inline SuccIterator(Term_ T) : Term(T), idx(0) {// begin iterator |
| } |
| inline SuccIterator(Term_ T, bool) // end iterator |
| : Term(T) { |
| if (Term) |
| idx = Term->getNumSuccessors(); |
| else |
| // Term == NULL happens, if a basic block is not fully constructed and |
| // consequently getTerminator() returns NULL. In this case we construct a |
| // SuccIterator which describes a basic block that has zero successors. |
| // Defining SuccIterator for incomplete and malformed CFGs is especially |
| // useful for debugging. |
| idx = 0; |
| } |
| |
| inline const Self &operator=(const Self &I) { |
| assert(Term == I.Term &&"Cannot assign iterators to two different blocks!"); |
| idx = I.idx; |
| return *this; |
| } |
| |
| /// getSuccessorIndex - This is used to interface between code that wants to |
| /// operate on terminator instructions directly. |
| unsigned getSuccessorIndex() const { return idx; } |
| |
| inline bool operator==(const Self& x) const { return idx == x.idx; } |
| inline bool operator!=(const Self& x) const { return !operator==(x); } |
| |
| inline reference operator*() const { return Term->getSuccessor(idx); } |
| inline pointer operator->() const { return operator*(); } |
| |
| inline Self& operator++() { ++idx; return *this; } // Preincrement |
| |
| inline Self operator++(int) { // Postincrement |
| Self tmp = *this; ++*this; return tmp; |
| } |
| |
| inline Self& operator--() { --idx; return *this; } // Predecrement |
| inline Self operator--(int) { // Postdecrement |
| Self tmp = *this; --*this; return tmp; |
| } |
| |
| inline bool operator<(const Self& x) const { |
| assert(Term == x.Term && "Cannot compare iterators of different blocks!"); |
| return idx < x.idx; |
| } |
| |
| inline bool operator<=(const Self& x) const { |
| assert(Term == x.Term && "Cannot compare iterators of different blocks!"); |
| return idx <= x.idx; |
| } |
| inline bool operator>=(const Self& x) const { |
| assert(Term == x.Term && "Cannot compare iterators of different blocks!"); |
| return idx >= x.idx; |
| } |
| |
| inline bool operator>(const Self& x) const { |
| assert(Term == x.Term && "Cannot compare iterators of different blocks!"); |
| return idx > x.idx; |
| } |
| |
| inline Self& operator+=(int Right) { |
| unsigned new_idx = idx + Right; |
| assert(index_is_valid(new_idx) && "Iterator index out of bound"); |
| idx = new_idx; |
| return *this; |
| } |
| |
| inline Self operator+(int Right) const { |
| Self tmp = *this; |
| tmp += Right; |
| return tmp; |
| } |
| |
| inline Self& operator-=(int Right) { |
| return operator+=(-Right); |
| } |
| |
| inline Self operator-(int Right) const { |
| return operator+(-Right); |
| } |
| |
| inline int operator-(const Self& x) const { |
| assert(Term == x.Term && "Cannot work on iterators of different blocks!"); |
| int distance = idx - x.idx; |
| return distance; |
| } |
| |
| inline SuccessorProxy operator[](int offset) { |
| Self tmp = *this; |
| tmp += offset; |
| return SuccessorProxy(tmp); |
| } |
| |
| /// Get the source BB of this iterator. |
| inline BB_ *getSource() { |
| assert(Term && "Source not available, if basic block was malformed"); |
| return Term->getParent(); |
| } |
| }; |
| |
| typedef SuccIterator<TerminatorInst*, BasicBlock> succ_iterator; |
| typedef SuccIterator<const TerminatorInst*, |
| const BasicBlock> succ_const_iterator; |
| |
| inline succ_iterator succ_begin(BasicBlock *BB) { |
| return succ_iterator(BB->getTerminator()); |
| } |
| inline succ_const_iterator succ_begin(const BasicBlock *BB) { |
| return succ_const_iterator(BB->getTerminator()); |
| } |
| inline succ_iterator succ_end(BasicBlock *BB) { |
| return succ_iterator(BB->getTerminator(), true); |
| } |
| inline succ_const_iterator succ_end(const BasicBlock *BB) { |
| return succ_const_iterator(BB->getTerminator(), true); |
| } |
| |
| template <typename T, typename U> struct isPodLike<SuccIterator<T, U> > { |
| static const bool value = isPodLike<T>::value; |
| }; |
| |
| |
| |
| //===--------------------------------------------------------------------===// |
| // GraphTraits specializations for basic block graphs (CFGs) |
| //===--------------------------------------------------------------------===// |
| |
| // Provide specializations of GraphTraits to be able to treat a function as a |
| // graph of basic blocks... |
| |
| template <> struct GraphTraits<BasicBlock*> { |
| typedef BasicBlock NodeType; |
| typedef succ_iterator ChildIteratorType; |
| |
| static NodeType *getEntryNode(BasicBlock *BB) { return BB; } |
| static inline ChildIteratorType child_begin(NodeType *N) { |
| return succ_begin(N); |
| } |
| static inline ChildIteratorType child_end(NodeType *N) { |
| return succ_end(N); |
| } |
| }; |
| |
| template <> struct GraphTraits<const BasicBlock*> { |
| typedef const BasicBlock NodeType; |
| typedef succ_const_iterator ChildIteratorType; |
| |
| static NodeType *getEntryNode(const BasicBlock *BB) { return BB; } |
| |
| static inline ChildIteratorType child_begin(NodeType *N) { |
| return succ_begin(N); |
| } |
| static inline ChildIteratorType child_end(NodeType *N) { |
| return succ_end(N); |
| } |
| }; |
| |
| // Provide specializations of GraphTraits to be able to treat a function as a |
| // graph of basic blocks... and to walk it in inverse order. Inverse order for |
| // a function is considered to be when traversing the predecessor edges of a BB |
| // instead of the successor edges. |
| // |
| template <> struct GraphTraits<Inverse<BasicBlock*> > { |
| typedef BasicBlock NodeType; |
| typedef pred_iterator ChildIteratorType; |
| static NodeType *getEntryNode(Inverse<BasicBlock *> G) { return G.Graph; } |
| static inline ChildIteratorType child_begin(NodeType *N) { |
| return pred_begin(N); |
| } |
| static inline ChildIteratorType child_end(NodeType *N) { |
| return pred_end(N); |
| } |
| }; |
| |
| template <> struct GraphTraits<Inverse<const BasicBlock*> > { |
| typedef const BasicBlock NodeType; |
| typedef const_pred_iterator ChildIteratorType; |
| static NodeType *getEntryNode(Inverse<const BasicBlock*> G) { |
| return G.Graph; |
| } |
| static inline ChildIteratorType child_begin(NodeType *N) { |
| return pred_begin(N); |
| } |
| static inline ChildIteratorType child_end(NodeType *N) { |
| return pred_end(N); |
| } |
| }; |
| |
| |
| |
| //===--------------------------------------------------------------------===// |
| // GraphTraits specializations for function basic block graphs (CFGs) |
| //===--------------------------------------------------------------------===// |
| |
| // Provide specializations of GraphTraits to be able to treat a function as a |
| // graph of basic blocks... these are the same as the basic block iterators, |
| // except that the root node is implicitly the first node of the function. |
| // |
| template <> struct GraphTraits<Function*> : public GraphTraits<BasicBlock*> { |
| static NodeType *getEntryNode(Function *F) { return &F->getEntryBlock(); } |
| |
| // nodes_iterator/begin/end - Allow iteration over all nodes in the graph |
| typedef Function::iterator nodes_iterator; |
| static nodes_iterator nodes_begin(Function *F) { return F->begin(); } |
| static nodes_iterator nodes_end (Function *F) { return F->end(); } |
| static size_t size (Function *F) { return F->size(); } |
| }; |
| template <> struct GraphTraits<const Function*> : |
| public GraphTraits<const BasicBlock*> { |
| static NodeType *getEntryNode(const Function *F) {return &F->getEntryBlock();} |
| |
| // nodes_iterator/begin/end - Allow iteration over all nodes in the graph |
| typedef Function::const_iterator nodes_iterator; |
| static nodes_iterator nodes_begin(const Function *F) { return F->begin(); } |
| static nodes_iterator nodes_end (const Function *F) { return F->end(); } |
| static size_t size (const Function *F) { return F->size(); } |
| }; |
| |
| |
| // Provide specializations of GraphTraits to be able to treat a function as a |
| // graph of basic blocks... and to walk it in inverse order. Inverse order for |
| // a function is considered to be when traversing the predecessor edges of a BB |
| // instead of the successor edges. |
| // |
| template <> struct GraphTraits<Inverse<Function*> > : |
| public GraphTraits<Inverse<BasicBlock*> > { |
| static NodeType *getEntryNode(Inverse<Function*> G) { |
| return &G.Graph->getEntryBlock(); |
| } |
| }; |
| template <> struct GraphTraits<Inverse<const Function*> > : |
| public GraphTraits<Inverse<const BasicBlock*> > { |
| static NodeType *getEntryNode(Inverse<const Function *> G) { |
| return &G.Graph->getEntryBlock(); |
| } |
| }; |
| |
| } // End llvm namespace |
| |
| #endif |