Timer.h revision 14112e51697e56788fcb32f4255833499c2738b5
1//===-- llvm/Support/Timer.h - Interval Timing Support ----------*- 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 three classes: Timer, TimeRegion, and TimerGroup, 11// documented below. 12// 13//===----------------------------------------------------------------------===// 14 15#ifndef LLVM_SUPPORT_TIMER_H 16#define LLVM_SUPPORT_TIMER_H 17 18#include "llvm/Support/DataTypes.h" 19#include <string> 20#include <vector> 21#include <iosfwd> 22#include <cassert> 23 24namespace llvm { 25 26class TimerGroup; 27 28/// Timer - This class is used to track the amount of time spent between 29/// invocations of it's startTimer()/stopTimer() methods. Given appropriate OS 30/// support it can also keep track of the RSS of the program at various points. 31/// By default, the Timer will print the amount of time it has captured to 32/// standard error when the laster timer is destroyed, otherwise it is printed 33/// when its TimerGroup is destroyed. Timers do not print their information 34/// if they are never started. 35/// 36class Timer { 37 int64_t Elapsed; // Wall clock time elapsed in seconds 38 int64_t UserTime; // User time elapsed 39 int64_t SystemTime; // System time elapsed 40 int64_t MemUsed; // Memory allocated (in bytes) 41 int64_t PeakMem; // Peak memory used 42 int64_t PeakMemBase; // Temporary for peak calculation... 43 std::string Name; // The name of this time variable 44 bool Started; // Has this time variable ever been started? 45 TimerGroup *TG; // The TimerGroup this Timer is in. 46public: 47 explicit Timer(const std::string &N); 48 Timer(const std::string &N, TimerGroup &tg); 49 Timer(const Timer &T); 50 ~Timer(); 51 52 int64_t getProcessTime() const { return UserTime+SystemTime; } 53 int64_t getWallTime() const { return Elapsed; } 54 int64_t getMemUsed() const { return MemUsed; } 55 int64_t getPeakMem() const { return PeakMem; } 56 std::string getName() const { return Name; } 57 58 const Timer &operator=(const Timer &T) { 59 Elapsed = T.Elapsed; 60 UserTime = T.UserTime; 61 SystemTime = T.SystemTime; 62 MemUsed = T.MemUsed; 63 PeakMem = T.PeakMem; 64 PeakMemBase = T.PeakMemBase; 65 Name = T.Name; 66 Started = T.Started; 67 assert(TG == T.TG && "Can only assign timers in the same TimerGroup!"); 68 return *this; 69 } 70 71 // operator< - Allow sorting... 72 bool operator<(const Timer &T) const { 73 // Sort by Wall Time elapsed, as it is the only thing really accurate 74 return Elapsed < T.Elapsed; 75 } 76 bool operator>(const Timer &T) const { return T.operator<(*this); } 77 78 /// startTimer - Start the timer running. Time between calls to 79 /// startTimer/stopTimer is counted by the Timer class. Note that these calls 80 /// must be correctly paired. 81 /// 82 void startTimer(); 83 84 /// stopTimer - Stop the timer. 85 /// 86 void stopTimer(); 87 88 /// addPeakMemoryMeasurement - This method should be called whenever memory 89 /// usage needs to be checked. It adds a peak memory measurement to the 90 /// currently active timers, which will be printed when the timer group prints 91 /// 92 static void addPeakMemoryMeasurement(); 93 94 /// print - Print the current timer to standard error, and reset the "Started" 95 /// flag. 96 void print(const Timer &Total, std::ostream &OS); 97 98private: 99 friend class TimerGroup; 100 101 // Copy ctor, initialize with no TG member. 102 Timer(bool, const Timer &T); 103 104 /// sum - Add the time accumulated in the specified timer into this timer. 105 /// 106 void sum(const Timer &T); 107}; 108 109 110/// The TimeRegion class is used as a helper class to call the startTimer() and 111/// stopTimer() methods of the Timer class. When the object is constructed, it 112/// starts the timer specified as it's argument. When it is destroyed, it stops 113/// the relevant timer. This makes it easy to time a region of code. 114/// 115class TimeRegion { 116 Timer *T; 117 TimeRegion(const TimeRegion &); // DO NOT IMPLEMENT 118public: 119 explicit TimeRegion(Timer &t) : T(&t) { 120 T->startTimer(); 121 } 122 explicit TimeRegion(Timer *t) : T(t) { 123 if (T) 124 T->startTimer(); 125 } 126 ~TimeRegion() { 127 if (T) 128 T->stopTimer(); 129 } 130}; 131 132 133/// NamedRegionTimer - This class is basically a combination of TimeRegion and 134/// Timer. It allows you to declare a new timer, AND specify the region to 135/// time, all in one statement. All timers with the same name are merged. This 136/// is primarily used for debugging and for hunting performance problems. 137/// 138struct NamedRegionTimer : public TimeRegion { 139 explicit NamedRegionTimer(const std::string &Name); 140 explicit NamedRegionTimer(const std::string &Name, 141 const std::string &GroupName); 142}; 143 144 145/// The TimerGroup class is used to group together related timers into a single 146/// report that is printed when the TimerGroup is destroyed. It is illegal to 147/// destroy a TimerGroup object before all of the Timers in it are gone. A 148/// TimerGroup can be specified for a newly created timer in its constructor. 149/// 150class TimerGroup { 151 std::string Name; 152 unsigned NumTimers; 153 std::vector<Timer> TimersToPrint; 154public: 155 explicit TimerGroup(const std::string &name) : Name(name), NumTimers(0) {} 156 ~TimerGroup() { 157 assert(NumTimers == 0 && 158 "TimerGroup destroyed before all contained timers!"); 159 } 160 161private: 162 friend class Timer; 163 void addTimer() { ++NumTimers; } 164 void removeTimer(); 165 void addTimerToPrint(const Timer &T) { 166 TimersToPrint.push_back(Timer(true, T)); 167 } 168}; 169 170} // End llvm namespace 171 172#endif 173