ProfileInfo.h revision 4bac4b9899ea4e56f4b5dd99887d4e460e0f13ad 
1//===- llvm/Analysis/ProfileInfo.h - Profile Info Interface -----*- 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 generic ProfileInfo interface, which is used as the
11// common interface used by all clients of profiling information, and
12// implemented either by making static guestimations, or by actually reading in
13// profiling information gathered by running the program.
14//
15// Note that to be useful, all profile-based optimizations should preserve
16// ProfileInfo, which requires that they notify it when changes to the CFG are
17// made. (This is not implemented yet.)
18//
19//===----------------------------------------------------------------------===//
20
21#ifndef LLVM_ANALYSIS_PROFILEINFO_H
22#define LLVM_ANALYSIS_PROFILEINFO_H
23
24#include "llvm/BasicBlock.h"
25#include <cassert>
26#include <string>
27#include <map>
28
29namespace llvm {
30  class Function;
31  class Pass;
32  class raw_ostream;
33
34  /// ProfileInfo Class - This class holds and maintains profiling
35  /// information for some unit of code.
36  class ProfileInfo {
37  public:
38    // Types for handling profiling information.
39    typedef std::pair<const BasicBlock*, const BasicBlock*> Edge;
40    typedef std::pair<Edge, double> EdgeWeight;
41    typedef std::map<Edge, double> EdgeWeights;
42    typedef std::map<const BasicBlock*, double> BlockCounts;
43
44  protected:
45    // EdgeInformation - Count the number of times a transition between two
46    // blocks is executed. As a special case, we also hold an edge from the
47    // null BasicBlock to the entry block to indicate how many times the
48    // function was entered.
49    std::map<const Function*, EdgeWeights> EdgeInformation;
50
51    // BlockInformation - Count the number of times a block is executed.
52    std::map<const Function*, BlockCounts> BlockInformation;
53
54    // FunctionInformation - Count the number of times a function is executed.
55    std::map<const Function*, double> FunctionInformation;
56  public:
57    static char ID; // Class identification, replacement for typeinfo
58    virtual ~ProfileInfo();  // We want to be subclassed
59
60    // MissingValue - The value that is returned for execution counts in case
61    // no value is available.
62    static const double MissingValue;
63
64    // getFunction() - Returns the Function for an Edge, checking for validity.
65    static const Function* getFunction(Edge e) {
66      assert(e.second && "Invalid ProfileInfo::Edge");
67      return e.second->getParent();
68    }
69
70    // getEdge() - Creates an Edge from two BasicBlocks.
71    static Edge getEdge(const BasicBlock *Src, const BasicBlock *Dest) {
72      return std::make_pair(Src, Dest);
73    }
74
75    //===------------------------------------------------------------------===//
76    /// Profile Information Queries
77    ///
78    double getExecutionCount(const Function *F);
79
80    double getExecutionCount(const BasicBlock *BB);
81
82    double getEdgeWeight(Edge e) const {
83      std::map<const Function*, EdgeWeights>::const_iterator J =
84        EdgeInformation.find(getFunction(e));
85      if (J == EdgeInformation.end()) return MissingValue;
86
87      EdgeWeights::const_iterator I = J->second.find(e);
88      if (I == J->second.end()) return MissingValue;
89
90      return I->second;
91    }
92
93    EdgeWeights &getEdgeWeights (const Function *F) {
94      return EdgeInformation[F];
95    }
96
97    //===------------------------------------------------------------------===//
98    /// Analysis Update Methods
99    ///
100
101  };
102
103  /// createProfileLoaderPass - This function returns a Pass that loads the
104  /// profiling information for the module from the specified filename, making
105  /// it available to the optimizers.
106  Pass *createProfileLoaderPass(const std::string &Filename);
107
108  raw_ostream& operator<<(raw_ostream &O, ProfileInfo::Edge E);
109
110} // End llvm namespace
111
112#endif
113