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 #ifndef LLVM_SUPPORT_TIMER_H 11 #define LLVM_SUPPORT_TIMER_H 12 13 #include "llvm/ADT/StringRef.h" 14 #include "llvm/Support/DataTypes.h" 15 #include <cassert> 16 #include <string> 17 #include <utility> 18 #include <vector> 19 20 namespace llvm { 21 22 class Timer; 23 class TimerGroup; 24 class raw_ostream; 25 26 class TimeRecord { 27 double WallTime; // Wall clock time elapsed in seconds 28 double UserTime; // User time elapsed 29 double SystemTime; // System time elapsed 30 ssize_t MemUsed; // Memory allocated (in bytes) 31 public: TimeRecord()32 TimeRecord() : WallTime(0), UserTime(0), SystemTime(0), MemUsed(0) {} 33 34 /// getCurrentTime - Get the current time and memory usage. If Start is true 35 /// we get the memory usage before the time, otherwise we get time before 36 /// memory usage. This matters if the time to get the memory usage is 37 /// significant and shouldn't be counted as part of a duration. 38 static TimeRecord getCurrentTime(bool Start = true); 39 getProcessTime()40 double getProcessTime() const { return UserTime+SystemTime; } getUserTime()41 double getUserTime() const { return UserTime; } getSystemTime()42 double getSystemTime() const { return SystemTime; } getWallTime()43 double getWallTime() const { return WallTime; } getMemUsed()44 ssize_t getMemUsed() const { return MemUsed; } 45 46 47 // operator< - Allow sorting. 48 bool operator<(const TimeRecord &T) const { 49 // Sort by Wall Time elapsed, as it is the only thing really accurate 50 return WallTime < T.WallTime; 51 } 52 53 void operator+=(const TimeRecord &RHS) { 54 WallTime += RHS.WallTime; 55 UserTime += RHS.UserTime; 56 SystemTime += RHS.SystemTime; 57 MemUsed += RHS.MemUsed; 58 } 59 void operator-=(const TimeRecord &RHS) { 60 WallTime -= RHS.WallTime; 61 UserTime -= RHS.UserTime; 62 SystemTime -= RHS.SystemTime; 63 MemUsed -= RHS.MemUsed; 64 } 65 66 /// print - Print the current timer to standard error, and reset the "Started" 67 /// flag. 68 void print(const TimeRecord &Total, raw_ostream &OS) const; 69 }; 70 71 /// Timer - This class is used to track the amount of time spent between 72 /// invocations of its startTimer()/stopTimer() methods. Given appropriate OS 73 /// support it can also keep track of the RSS of the program at various points. 74 /// By default, the Timer will print the amount of time it has captured to 75 /// standard error when the last timer is destroyed, otherwise it is printed 76 /// when its TimerGroup is destroyed. Timers do not print their information 77 /// if they are never started. 78 /// 79 class Timer { 80 TimeRecord Time; 81 std::string Name; // The name of this time variable. 82 bool Started; // Has this time variable ever been started? 83 TimerGroup *TG; // The TimerGroup this Timer is in. 84 85 Timer **Prev, *Next; // Doubly linked list of timers in the group. 86 public: Timer(StringRef N)87 explicit Timer(StringRef N) : TG(nullptr) { init(N); } Timer(StringRef N,TimerGroup & tg)88 Timer(StringRef N, TimerGroup &tg) : TG(nullptr) { init(N, tg); } Timer(const Timer & RHS)89 Timer(const Timer &RHS) : TG(nullptr) { 90 assert(!RHS.TG && "Can only copy uninitialized timers"); 91 } 92 const Timer &operator=(const Timer &T) { 93 assert(!TG && !T.TG && "Can only assign uninit timers"); 94 return *this; 95 } 96 ~Timer(); 97 98 // Create an uninitialized timer, client must use 'init'. Timer()99 explicit Timer() : TG(nullptr) {} 100 void init(StringRef N); 101 void init(StringRef N, TimerGroup &tg); 102 getName()103 const std::string &getName() const { return Name; } isInitialized()104 bool isInitialized() const { return TG != nullptr; } 105 106 /// startTimer - Start the timer running. Time between calls to 107 /// startTimer/stopTimer is counted by the Timer class. Note that these calls 108 /// must be correctly paired. 109 /// 110 void startTimer(); 111 112 /// stopTimer - Stop the timer. 113 /// 114 void stopTimer(); 115 116 private: 117 friend class TimerGroup; 118 }; 119 120 121 /// The TimeRegion class is used as a helper class to call the startTimer() and 122 /// stopTimer() methods of the Timer class. When the object is constructed, it 123 /// starts the timer specified as its argument. When it is destroyed, it stops 124 /// the relevant timer. This makes it easy to time a region of code. 125 /// 126 class TimeRegion { 127 Timer *T; 128 TimeRegion(const TimeRegion &) = delete; 129 public: TimeRegion(Timer & t)130 explicit TimeRegion(Timer &t) : T(&t) { 131 T->startTimer(); 132 } TimeRegion(Timer * t)133 explicit TimeRegion(Timer *t) : T(t) { 134 if (T) T->startTimer(); 135 } ~TimeRegion()136 ~TimeRegion() { 137 if (T) T->stopTimer(); 138 } 139 }; 140 141 142 /// NamedRegionTimer - This class is basically a combination of TimeRegion and 143 /// Timer. It allows you to declare a new timer, AND specify the region to 144 /// time, all in one statement. All timers with the same name are merged. This 145 /// is primarily used for debugging and for hunting performance problems. 146 /// 147 struct NamedRegionTimer : public TimeRegion { 148 explicit NamedRegionTimer(StringRef Name, 149 bool Enabled = true); 150 explicit NamedRegionTimer(StringRef Name, StringRef GroupName, 151 bool Enabled = true); 152 }; 153 154 155 /// The TimerGroup class is used to group together related timers into a single 156 /// report that is printed when the TimerGroup is destroyed. It is illegal to 157 /// destroy a TimerGroup object before all of the Timers in it are gone. A 158 /// TimerGroup can be specified for a newly created timer in its constructor. 159 /// 160 class TimerGroup { 161 std::string Name; 162 Timer *FirstTimer; // First timer in the group. 163 std::vector<std::pair<TimeRecord, std::string> > TimersToPrint; 164 165 TimerGroup **Prev, *Next; // Doubly linked list of TimerGroup's. 166 TimerGroup(const TimerGroup &TG) = delete; 167 void operator=(const TimerGroup &TG) = delete; 168 public: 169 explicit TimerGroup(StringRef name); 170 ~TimerGroup(); 171 setName(StringRef name)172 void setName(StringRef name) { Name.assign(name.begin(), name.end()); } 173 174 /// print - Print any started timers in this group and zero them. 175 void print(raw_ostream &OS); 176 177 /// printAll - This static method prints all timers and clears them all out. 178 static void printAll(raw_ostream &OS); 179 180 private: 181 friend class Timer; 182 void addTimer(Timer &T); 183 void removeTimer(Timer &T); 184 void PrintQueuedTimers(raw_ostream &OS); 185 }; 186 187 } // End llvm namespace 188 189 #endif 190