ProfileInfo.h revision 794fd75c67a2cdc128d67342c6d88a504d186896 
1//===- llvm/Analysis/ProfileInfo.h - Profile Info Interface -----*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file was developed by the LLVM research group and is distributed under
6// the University of Illinois Open Source 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.
18//
19//===----------------------------------------------------------------------===//
20
21#ifndef LLVM_ANALYSIS_PROFILEINFO_H
22#define LLVM_ANALYSIS_PROFILEINFO_H
23
24#include <string>
25#include <map>
26
27namespace llvm {
28  class BasicBlock;
29  class Pass;
30
31  /// ProfileInfo Class - This class holds and maintains edge profiling
32  /// information for some unit of code.
33  class ProfileInfo {
34  protected:
35    // EdgeCounts - Count the number of times a transition between two blocks is
36    // executed.  As a special case, we also hold an edge from the null
37    // BasicBlock to the entry block to indicate how many times the function was
38    // entered.
39    std::map<std::pair<BasicBlock*, BasicBlock*>, unsigned> EdgeCounts;
40  public:
41    static const int ID; // Class identification, replacement for typeinfo
42    virtual ~ProfileInfo();  // We want to be subclassed
43
44    //===------------------------------------------------------------------===//
45    /// Profile Information Queries
46    ///
47    unsigned getExecutionCount(BasicBlock *BB) const;
48
49    unsigned getEdgeWeight(BasicBlock *Src, BasicBlock *Dest) const {
50      std::map<std::pair<BasicBlock*, BasicBlock*>, unsigned>::const_iterator I=
51        EdgeCounts.find(std::make_pair(Src, Dest));
52      return I != EdgeCounts.end() ? I->second : 0;
53    }
54
55    //===------------------------------------------------------------------===//
56    /// Analysis Update Methods
57    ///
58
59  };
60
61  /// createProfileLoaderPass - This function returns a Pass that loads the
62  /// profiling information for the module from the specified filename, making
63  /// it available to the optimizers.
64  Pass *createProfileLoaderPass(const std::string &Filename);
65} // End llvm namespace
66
67#endif
68