summaryrefslogtreecommitdiff
path: root/include/llvm/Support/Timer.h
blob: d009d7fae5130f1af78e0e363cd92f31245eea36 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
//===-- llvm/Support/Timer.h - Interval Timing Support ----------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_SUPPORT_TIMER_H
#define LLVM_SUPPORT_TIMER_H

#include "llvm/ADT/StringRef.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/DataTypes.h"
#include <cassert>
#include <string>
#include <utility>
#include <vector>

namespace llvm {

class Timer;
class TimerGroup;
class raw_ostream;

class TimeRecord {
  double WallTime;       // Wall clock time elapsed in seconds
  double UserTime;       // User time elapsed
  double SystemTime;     // System time elapsed
  ssize_t MemUsed;       // Memory allocated (in bytes)
public:
  TimeRecord() : WallTime(0), UserTime(0), SystemTime(0), MemUsed(0) {}
  
  /// getCurrentTime - Get the current time and memory usage.  If Start is true
  /// we get the memory usage before the time, otherwise we get time before
  /// memory usage.  This matters if the time to get the memory usage is
  /// significant and shouldn't be counted as part of a duration.
  static TimeRecord getCurrentTime(bool Start = true);
  
  double getProcessTime() const { return UserTime+SystemTime; }
  double getUserTime() const { return UserTime; }
  double getSystemTime() const { return SystemTime; }
  double getWallTime() const { return WallTime; }
  ssize_t getMemUsed() const { return MemUsed; }
  
  
  // operator< - Allow sorting.
  bool operator<(const TimeRecord &T) const {
    // Sort by Wall Time elapsed, as it is the only thing really accurate
    return WallTime < T.WallTime;
  }
  
  void operator+=(const TimeRecord &RHS) {
    WallTime   += RHS.WallTime;
    UserTime   += RHS.UserTime;
    SystemTime += RHS.SystemTime;
    MemUsed    += RHS.MemUsed;
  }
  void operator-=(const TimeRecord &RHS) {
    WallTime   -= RHS.WallTime;
    UserTime   -= RHS.UserTime;
    SystemTime -= RHS.SystemTime;
    MemUsed    -= RHS.MemUsed;
  }
  
  /// print - Print the current timer to standard error, and reset the "Started"
  /// flag.
  void print(const TimeRecord &Total, raw_ostream &OS) const;
};
  
/// Timer - This class is used to track the amount of time spent between
/// invocations of its startTimer()/stopTimer() methods.  Given appropriate OS
/// support it can also keep track of the RSS of the program at various points.
/// By default, the Timer will print the amount of time it has captured to
/// standard error when the last timer is destroyed, otherwise it is printed
/// when its TimerGroup is destroyed.  Timers do not print their information
/// if they are never started.
///
class Timer {
  TimeRecord Time;
  std::string Name;      // The name of this time variable.
  bool Started;          // Has this time variable ever been started?
  TimerGroup *TG;        // The TimerGroup this Timer is in.
  
  Timer **Prev, *Next;   // Doubly linked list of timers in the group.
public:
  explicit Timer(StringRef N) : TG(0) { init(N); }
  Timer(StringRef N, TimerGroup &tg) : TG(0) { init(N, tg); }
  Timer(const Timer &RHS) : TG(0) {
    assert(RHS.TG == 0 && "Can only copy uninitialized timers");
  }
  const Timer &operator=(const Timer &T) {
    assert(TG == 0 && T.TG == 0 && "Can only assign uninit timers");
    return *this;
  }
  ~Timer();

  // Create an uninitialized timer, client must use 'init'.
  explicit Timer() : TG(0) {}
  void init(StringRef N);
  void init(StringRef N, TimerGroup &tg);
  
  const std::string &getName() const { return Name; }
  bool isInitialized() const { return TG != 0; }
  
  /// startTimer - Start the timer running.  Time between calls to
  /// startTimer/stopTimer is counted by the Timer class.  Note that these calls
  /// must be correctly paired.
  ///
  void startTimer();

  /// stopTimer - Stop the timer.
  ///
  void stopTimer();

private:
  friend class TimerGroup;
};


/// The TimeRegion class is used as a helper class to call the startTimer() and
/// stopTimer() methods of the Timer class.  When the object is constructed, it
/// starts the timer specified as its argument.  When it is destroyed, it stops
/// the relevant timer.  This makes it easy to time a region of code.
///
class TimeRegion {
  Timer *T;
  TimeRegion(const TimeRegion &) LLVM_DELETED_FUNCTION;
public:
  explicit TimeRegion(Timer &t) : T(&t) {
    T->startTimer();
  }
  explicit TimeRegion(Timer *t) : T(t) {
    if (T) T->startTimer();
  }
  ~TimeRegion() {
    if (T) T->stopTimer();
  }
};


/// NamedRegionTimer - This class is basically a combination of TimeRegion and
/// Timer.  It allows you to declare a new timer, AND specify the region to
/// time, all in one statement.  All timers with the same name are merged.  This
/// is primarily used for debugging and for hunting performance problems.
///
struct NamedRegionTimer : public TimeRegion {
  explicit NamedRegionTimer(StringRef Name,
                            bool Enabled = true);
  explicit NamedRegionTimer(StringRef Name, StringRef GroupName,
                            bool Enabled = true);
};


/// The TimerGroup class is used to group together related timers into a single
/// report that is printed when the TimerGroup is destroyed.  It is illegal to
/// destroy a TimerGroup object before all of the Timers in it are gone.  A
/// TimerGroup can be specified for a newly created timer in its constructor.
///
class TimerGroup {
  std::string Name;
  Timer *FirstTimer;   // First timer in the group.
  std::vector<std::pair<TimeRecord, std::string> > TimersToPrint;
  
  TimerGroup **Prev, *Next; // Doubly linked list of TimerGroup's.
  TimerGroup(const TimerGroup &TG) LLVM_DELETED_FUNCTION;
  void operator=(const TimerGroup &TG) LLVM_DELETED_FUNCTION;
public:
  explicit TimerGroup(StringRef name);
  ~TimerGroup();

  void setName(StringRef name) { Name.assign(name.begin(), name.end()); }

  /// print - Print any started timers in this group and zero them.
  void print(raw_ostream &OS);
  
  /// printAll - This static method prints all timers and clears them all out.
  static void printAll(raw_ostream &OS);
  
private:
  friend class Timer;
  void addTimer(Timer &T);
  void removeTimer(Timer &T);
  void PrintQueuedTimers(raw_ostream &OS);
};

} // End llvm namespace

#endif