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