1 //===- llvm/Analysis/Interval.h - Interval Class Declaration ----*- 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 contains the declaration of the Interval class, which 11 // represents a set of CFG nodes and is a portion of an interval partition. 12 // 13 // Intervals have some interesting and useful properties, including the 14 // following: 15 // 1. The header node of an interval dominates all of the elements of the 16 // interval 17 // 18 //===----------------------------------------------------------------------===// 19 20 #ifndef LLVM_ANALYSIS_INTERVAL_H 21 #define LLVM_ANALYSIS_INTERVAL_H 22 23 #include "llvm/ADT/GraphTraits.h" 24 #include <vector> 25 26 namespace llvm { 27 28 class BasicBlock; 29 class raw_ostream; 30 31 //===----------------------------------------------------------------------===// 32 // 33 /// Interval Class - An Interval is a set of nodes defined such that every node 34 /// in the interval has all of its predecessors in the interval (except for the 35 /// header) 36 /// 37 class Interval { 38 /// HeaderNode - The header BasicBlock, which dominates all BasicBlocks in this 39 /// interval. Also, any loops in this interval must go through the HeaderNode. 40 /// 41 BasicBlock *HeaderNode; 42 public: 43 typedef std::vector<BasicBlock*>::iterator succ_iterator; 44 typedef std::vector<BasicBlock*>::iterator pred_iterator; 45 typedef std::vector<BasicBlock*>::iterator node_iterator; 46 47 inline Interval(BasicBlock *Header) : HeaderNode(Header) { 48 Nodes.push_back(Header); 49 } 50 51 inline BasicBlock *getHeaderNode() const { return HeaderNode; } 52 53 /// Nodes - The basic blocks in this interval. 54 /// 55 std::vector<BasicBlock*> Nodes; 56 57 /// Successors - List of BasicBlocks that are reachable directly from nodes in 58 /// this interval, but are not in the interval themselves. 59 /// These nodes necessarily must be header nodes for other intervals. 60 /// 61 std::vector<BasicBlock*> Successors; 62 63 /// Predecessors - List of BasicBlocks that have this Interval's header block 64 /// as one of their successors. 65 /// 66 std::vector<BasicBlock*> Predecessors; 67 68 /// contains - Find out if a basic block is in this interval 69 inline bool contains(BasicBlock *BB) const { 70 for (BasicBlock *Node : Nodes) 71 if (Node == BB) 72 return true; 73 return false; 74 // I don't want the dependency on <algorithm> 75 //return find(Nodes.begin(), Nodes.end(), BB) != Nodes.end(); 76 } 77 78 /// isSuccessor - find out if a basic block is a successor of this Interval 79 inline bool isSuccessor(BasicBlock *BB) const { 80 for (BasicBlock *Successor : Successors) 81 if (Successor == BB) 82 return true; 83 return false; 84 // I don't want the dependency on <algorithm> 85 //return find(Successors.begin(), Successors.end(), BB) != Successors.end(); 86 } 87 88 /// Equality operator. It is only valid to compare two intervals from the 89 /// same partition, because of this, all we have to check is the header node 90 /// for equality. 91 /// 92 inline bool operator==(const Interval &I) const { 93 return HeaderNode == I.HeaderNode; 94 } 95 96 /// isLoop - Find out if there is a back edge in this interval... 97 bool isLoop() const; 98 99 /// print - Show contents in human readable format... 100 void print(raw_ostream &O) const; 101 }; 102 103 /// succ_begin/succ_end - define methods so that Intervals may be used 104 /// just like BasicBlocks can with the succ_* functions, and *::succ_iterator. 105 /// 106 inline Interval::succ_iterator succ_begin(Interval *I) { 107 return I->Successors.begin(); 108 } 109 inline Interval::succ_iterator succ_end(Interval *I) { 110 return I->Successors.end(); 111 } 112 113 /// pred_begin/pred_end - define methods so that Intervals may be used 114 /// just like BasicBlocks can with the pred_* functions, and *::pred_iterator. 115 /// 116 inline Interval::pred_iterator pred_begin(Interval *I) { 117 return I->Predecessors.begin(); 118 } 119 inline Interval::pred_iterator pred_end(Interval *I) { 120 return I->Predecessors.end(); 121 } 122 123 template <> struct GraphTraits<Interval*> { 124 typedef Interval NodeType; 125 typedef Interval::succ_iterator ChildIteratorType; 126 127 static NodeType *getEntryNode(Interval *I) { return I; } 128 129 /// nodes_iterator/begin/end - Allow iteration over all nodes in the graph 130 static inline ChildIteratorType child_begin(NodeType *N) { 131 return succ_begin(N); 132 } 133 static inline ChildIteratorType child_end(NodeType *N) { 134 return succ_end(N); 135 } 136 }; 137 138 template <> struct GraphTraits<Inverse<Interval*> > { 139 typedef Interval NodeType; 140 typedef Interval::pred_iterator ChildIteratorType; 141 static NodeType *getEntryNode(Inverse<Interval *> G) { return G.Graph; } 142 static inline ChildIteratorType child_begin(NodeType *N) { 143 return pred_begin(N); 144 } 145 static inline ChildIteratorType child_end(NodeType *N) { 146 return pred_end(N); 147 } 148 }; 149 150 } // End llvm namespace 151 152 #endif 153
