ProfileInfo.h revision c43782cf7163805fb6d727382b5f807ea035b2b0 
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
33  /// ProfileInfo Class - This class holds and maintains profiling
34  /// information for some unit of code.
35  class ProfileInfo {
36  public:
37    // Types for handling profiling information.
38    typedef std::pair<const BasicBlock*, const BasicBlock*> Edge;
39    typedef std::map<Edge, double> EdgeCounts;
40    typedef std::map<const BasicBlock*, double> BlockCounts;
41
42  protected:
43    // EdgeCounts - Count the number of times a transition between two blocks is
44    // executed.  As a special case, we also hold an edge from the null
45    // BasicBlock to the entry block to indicate how many times the function was
46    // entered.
47    std::map<const Function*, EdgeCounts> EdgeInformation;
48
49    // BlockCounts - Count the number of times a block is executed.
50    std::map<const Function*, BlockCounts> BlockInformation;
51
52    // FunctionCounts - Count the number of times a function is executed.
53    std::map<const Function*, double> FunctionInformation;
54  public:
55    static char ID; // Class identification, replacement for typeinfo
56    virtual ~ProfileInfo();  // We want to be subclassed
57
58    // MissingValue - The value that is returned for execution counts in case
59    // no value is available.
60    static const int MissingValue = -1;
61
62    // getFunction() - Returns the Function for an Edge, checking for validity.
63    static const Function* getFunction(Edge e) {
64      assert(e.second && "Invalid ProfileInfo::Edge");
65      return e.second->getParent();
66    }
67
68    // getEdge() - Creates an Edge from two BasicBlocks.
69    static Edge getEdge(const BasicBlock* Src, const BasicBlock* Dest) {
70      return std::make_pair(Src, Dest);
71    }
72
73    //===------------------------------------------------------------------===//
74    /// Profile Information Queries
75    ///
76    double getExecutionCount(const Function *F);
77
78    double getExecutionCount(const BasicBlock *BB);
79
80    double getEdgeWeight(Edge e) const {
81      std::map<const Function*, EdgeCounts>::const_iterator J =
82        EdgeInformation.find(getFunction(e));
83      if (J == EdgeInformation.end()) return MissingValue;
84
85      EdgeCounts::const_iterator I = J->second.find(e);
86      if (I == J->second.end()) return MissingValue;
87
88      return I->second;
89    }
90
91    //===------------------------------------------------------------------===//
92    /// Analysis Update Methods
93    ///
94
95  };
96
97  /// createProfileLoaderPass - This function returns a Pass that loads the
98  /// profiling information for the module from the specified filename, making
99  /// it available to the optimizers.
100  Pass *createProfileLoaderPass(const std::string &Filename);
101} // End llvm namespace
102
103#endif
104