LLVM  3.7.0
Interval.h
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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 (unsigned i = 0; i < Nodes.size(); ++i)
71  if (Nodes[i] == BB) return true;
72  return false;
73  // I don't want the dependency on <algorithm>
74  //return find(Nodes.begin(), Nodes.end(), BB) != Nodes.end();
75  }
76 
77  /// isSuccessor - find out if a basic block is a successor of this Interval
78  inline bool isSuccessor(BasicBlock *BB) const {
79  for (unsigned i = 0; i < Successors.size(); ++i)
80  if (Successors[i] == BB) return true;
81  return false;
82  // I don't want the dependency on <algorithm>
83  //return find(Successors.begin(), Successors.end(), BB) != Successors.end();
84  }
85 
86  /// Equality operator. It is only valid to compare two intervals from the
87  /// same partition, because of this, all we have to check is the header node
88  /// for equality.
89  ///
90  inline bool operator==(const Interval &I) const {
91  return HeaderNode == I.HeaderNode;
92  }
93 
94  /// isLoop - Find out if there is a back edge in this interval...
95  bool isLoop() const;
96 
97  /// print - Show contents in human readable format...
98  void print(raw_ostream &O) const;
99 };
100 
101 /// succ_begin/succ_end - define methods so that Intervals may be used
102 /// just like BasicBlocks can with the succ_* functions, and *::succ_iterator.
103 ///
105  return I->Successors.begin();
106 }
108  return I->Successors.end();
109 }
110 
111 /// pred_begin/pred_end - define methods so that Intervals may be used
112 /// just like BasicBlocks can with the pred_* functions, and *::pred_iterator.
113 ///
115  return I->Predecessors.begin();
116 }
118  return I->Predecessors.end();
119 }
120 
121 template <> struct GraphTraits<Interval*> {
124 
125  static NodeType *getEntryNode(Interval *I) { return I; }
126 
127  /// nodes_iterator/begin/end - Allow iteration over all nodes in the graph
128  static inline ChildIteratorType child_begin(NodeType *N) {
129  return succ_begin(N);
130  }
131  static inline ChildIteratorType child_end(NodeType *N) {
132  return succ_end(N);
133  }
134 };
135 
136 template <> struct GraphTraits<Inverse<Interval*> > {
139  static NodeType *getEntryNode(Inverse<Interval *> G) { return G.Graph; }
140  static inline ChildIteratorType child_begin(NodeType *N) {
141  return pred_begin(N);
142  }
143  static inline ChildIteratorType child_end(NodeType *N) {
144  return pred_end(N);
145  }
146 };
147 
148 } // End llvm namespace
149 
150 #endif
Interval::pred_iterator ChildIteratorType
Definition: Interval.h:138
Various leaf nodes.
Definition: ISDOpcodes.h:60
DominatorTree GraphTraits specialization so the DominatorTree can be iterable by generic graph iterat...
Definition: GraphTraits.h:27
Interval Class - An Interval is a set of nodes defined such that every node in the interval has all o...
Definition: Interval.h:37
Interval::succ_iterator ChildIteratorType
Definition: Interval.h:123
static NodeType * getEntryNode(Inverse< Interval * > G)
Definition: Interval.h:139
std::vector< BasicBlock * >::iterator node_iterator
Definition: Interval.h:45
static ChildIteratorType child_begin(NodeType *N)
Definition: Interval.h:140
#define G(x, y, z)
Definition: MD5.cpp:52
Interval::succ_iterator succ_begin(Interval *I)
succ_begin/succ_end - define methods so that Intervals may be used just like BasicBlocks can with the...
Definition: Interval.h:104
bool contains(BasicBlock *BB) const
contains - Find out if a basic block is in this interval
Definition: Interval.h:69
static ChildIteratorType child_end(NodeType *N)
Definition: Interval.h:143
static ChildIteratorType child_end(NodeType *N)
Definition: Interval.h:131
Interval::succ_iterator succ_end(Interval *I)
Definition: Interval.h:107
LLVM Basic Block Representation.
Definition: BasicBlock.h:65
void print(raw_ostream &O) const
print - Show contents in human readable format...
Definition: Interval.cpp:40
Interval::pred_iterator pred_begin(Interval *I)
pred_begin/pred_end - define methods so that Intervals may be used just like BasicBlocks can with the...
Definition: Interval.h:114
static ChildIteratorType child_begin(NodeType *N)
nodes_iterator/begin/end - Allow iteration over all nodes in the graph
Definition: Interval.h:128
Interval::pred_iterator pred_end(Interval *I)
Definition: Interval.h:117
std::vector< BasicBlock * > Nodes
Nodes - The basic blocks in this interval.
Definition: Interval.h:55
static NodeType * getEntryNode(Interval *I)
Definition: Interval.h:125
const GraphType & Graph
Definition: GraphTraits.h:79
bool isLoop() const
isLoop - Find out if there is a back edge in this interval...
Definition: Interval.cpp:29
std::vector< BasicBlock * > Predecessors
Predecessors - List of BasicBlocks that have this Interval's header block as one of their successors...
Definition: Interval.h:66
bool operator==(const Interval &I) const
Equality operator.
Definition: Interval.h:90
BasicBlock * getHeaderNode() const
Definition: Interval.h:51
std::vector< BasicBlock * > Successors
Successors - List of BasicBlocks that are reachable directly from nodes in this interval, but are not in the interval themselves.
Definition: Interval.h:61
bool isSuccessor(BasicBlock *BB) const
isSuccessor - find out if a basic block is a successor of this Interval
Definition: Interval.h:78
#define I(x, y, z)
Definition: MD5.cpp:54
#define N
std::vector< BasicBlock * >::iterator succ_iterator
Definition: Interval.h:43
This class implements an extremely fast bulk output stream that can only output to a stream...
Definition: raw_ostream.h:38
Interval(BasicBlock *Header)
Definition: Interval.h:47
std::vector< BasicBlock * >::iterator pred_iterator
Definition: Interval.h:44