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/StringMap.h" 14 #include "llvm/ADT/StringRef.h" 15 #include "llvm/Support/DataTypes.h" 16 #include <cassert> 17 #include <string> 18 #include <utility> 19 #include <vector> 20 21 namespace llvm { 22 23 class Timer; 24 class TimerGroup; 25 class raw_ostream; 26 27 class TimeRecord { 28 double WallTime; ///< Wall clock time elapsed in seconds. 29 double UserTime; ///< User time elapsed. 30 double SystemTime; ///< System time elapsed. 31 ssize_t MemUsed; ///< Memory allocated (in bytes). 32 public: TimeRecord()33 TimeRecord() : WallTime(0), UserTime(0), SystemTime(0), MemUsed(0) {} 34 35 /// Get the current time and memory usage. If Start is true we get the memory 36 /// usage before the time, otherwise we get time before memory usage. This 37 /// matters if the time to get the memory usage is significant and shouldn't 38 /// be counted as part of a duration. 39 static TimeRecord getCurrentTime(bool Start = true); 40 getProcessTime()41 double getProcessTime() const { return UserTime + SystemTime; } getUserTime()42 double getUserTime() const { return UserTime; } getSystemTime()43 double getSystemTime() const { return SystemTime; } getWallTime()44 double getWallTime() const { return WallTime; } getMemUsed()45 ssize_t getMemUsed() const { return MemUsed; } 46 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 the current time record to \p OS, with a breakdown showing 66 /// contributions to the \p Total time record. 67 void print(const TimeRecord &Total, raw_ostream &OS) const; 68 }; 69 70 /// This class is used to track the amount of time spent between invocations of 71 /// its startTimer()/stopTimer() methods. Given appropriate OS support it can 72 /// also keep track of the RSS of the program at various points. By default, 73 /// the Timer will print the amount of time it has captured to standard error 74 /// when the last timer is destroyed, otherwise it is printed when its 75 /// TimerGroup is destroyed. Timers do not print their information if they are 76 /// never started. 77 class Timer { 78 TimeRecord Time; ///< The total time captured. 79 TimeRecord StartTime; ///< The time startTimer() was last called. 80 std::string Name; ///< The name of this time variable. 81 std::string Description; ///< Description of this time variable. 82 bool Running; ///< Is the timer currently running? 83 bool Triggered; ///< Has the timer ever been triggered? 84 TimerGroup *TG = nullptr; ///< The TimerGroup this Timer is in. 85 86 Timer **Prev; ///< Pointer to \p Next of previous timer in group. 87 Timer *Next; ///< Next timer in the group. 88 public: Timer(StringRef Name,StringRef Description)89 explicit Timer(StringRef Name, StringRef Description) { 90 init(Name, Description); 91 } Timer(StringRef Name,StringRef Description,TimerGroup & tg)92 Timer(StringRef Name, StringRef Description, TimerGroup &tg) { 93 init(Name, Description, tg); 94 } Timer(const Timer & RHS)95 Timer(const Timer &RHS) { 96 assert(!RHS.TG && "Can only copy uninitialized timers"); 97 } 98 const Timer &operator=(const Timer &T) { 99 assert(!TG && !T.TG && "Can only assign uninit timers"); 100 return *this; 101 } 102 ~Timer(); 103 104 /// Create an uninitialized timer, client must use 'init'. Timer()105 explicit Timer() {} 106 void init(StringRef Name, StringRef Description); 107 void init(StringRef Name, StringRef Description, TimerGroup &tg); 108 getName()109 const std::string &getName() const { return Name; } getDescription()110 const std::string &getDescription() const { return Description; } isInitialized()111 bool isInitialized() const { return TG != nullptr; } 112 113 /// Check if the timer is currently running. isRunning()114 bool isRunning() const { return Running; } 115 116 /// Check if startTimer() has ever been called on this timer. hasTriggered()117 bool hasTriggered() const { return Triggered; } 118 119 /// Start the timer running. Time between calls to startTimer/stopTimer is 120 /// counted by the Timer class. Note that these calls must be correctly 121 /// paired. 122 void startTimer(); 123 124 /// Stop the timer. 125 void stopTimer(); 126 127 /// Clear the timer state. 128 void clear(); 129 130 /// Return the duration for which this timer has been running. getTotalTime()131 TimeRecord getTotalTime() const { return Time; } 132 133 private: 134 friend class TimerGroup; 135 }; 136 137 /// The TimeRegion class is used as a helper class to call the startTimer() and 138 /// stopTimer() methods of the Timer class. When the object is constructed, it 139 /// starts the timer specified as its argument. When it is destroyed, it stops 140 /// the relevant timer. This makes it easy to time a region of code. 141 class TimeRegion { 142 Timer *T; 143 TimeRegion(const TimeRegion &) = delete; 144 145 public: TimeRegion(Timer & t)146 explicit TimeRegion(Timer &t) : T(&t) { 147 T->startTimer(); 148 } TimeRegion(Timer * t)149 explicit TimeRegion(Timer *t) : T(t) { 150 if (T) T->startTimer(); 151 } ~TimeRegion()152 ~TimeRegion() { 153 if (T) T->stopTimer(); 154 } 155 }; 156 157 /// This class is basically a combination of TimeRegion and Timer. It allows 158 /// you to declare a new timer, AND specify the region to time, all in one 159 /// statement. All timers with the same name are merged. This is primarily 160 /// used for debugging and for hunting performance problems. 161 struct NamedRegionTimer : public TimeRegion { 162 explicit NamedRegionTimer(StringRef Name, StringRef Description, 163 StringRef GroupName, 164 StringRef GroupDescription, bool Enabled = true); 165 }; 166 167 /// The TimerGroup class is used to group together related timers into a single 168 /// report that is printed when the TimerGroup is destroyed. It is illegal to 169 /// destroy a TimerGroup object before all of the Timers in it are gone. A 170 /// TimerGroup can be specified for a newly created timer in its constructor. 171 class TimerGroup { 172 struct PrintRecord { 173 TimeRecord Time; 174 std::string Name; 175 std::string Description; 176 177 PrintRecord(const PrintRecord &Other) = default; PrintRecordPrintRecord178 PrintRecord(const TimeRecord &Time, const std::string &Name, 179 const std::string &Description) 180 : Time(Time), Name(Name), Description(Description) {} 181 182 bool operator <(const PrintRecord &Other) const { 183 return Time < Other.Time; 184 } 185 }; 186 std::string Name; 187 std::string Description; 188 Timer *FirstTimer = nullptr; ///< First timer in the group. 189 std::vector<PrintRecord> TimersToPrint; 190 191 TimerGroup **Prev; ///< Pointer to Next field of previous timergroup in list. 192 TimerGroup *Next; ///< Pointer to next timergroup in list. 193 TimerGroup(const TimerGroup &TG) = delete; 194 void operator=(const TimerGroup &TG) = delete; 195 196 public: 197 explicit TimerGroup(StringRef Name, StringRef Description); 198 199 explicit TimerGroup(StringRef Name, StringRef Description, 200 const StringMap<TimeRecord> &Records); 201 202 ~TimerGroup(); 203 setName(StringRef NewName,StringRef NewDescription)204 void setName(StringRef NewName, StringRef NewDescription) { 205 Name.assign(NewName.begin(), NewName.end()); 206 Description.assign(NewDescription.begin(), NewDescription.end()); 207 } 208 209 /// Print any started timers in this group and zero them. 210 void print(raw_ostream &OS); 211 212 /// This static method prints all timers and clears them all out. 213 static void printAll(raw_ostream &OS); 214 215 const char *printJSONValues(raw_ostream &OS, const char *delim); 216 217 /// Prints all timers as JSON key/value pairs, and clears them all out. 218 static const char *printAllJSONValues(raw_ostream &OS, const char *delim); 219 220 /// Ensure global timer group lists are initialized. This function is mostly 221 /// used by the Statistic code to influence the construction and destruction 222 /// order of the global timer lists. 223 static void ConstructTimerLists(); 224 private: 225 friend class Timer; 226 friend void PrintStatisticsJSON(raw_ostream &OS); 227 void addTimer(Timer &T); 228 void removeTimer(Timer &T); 229 void prepareToPrintList(); 230 void PrintQueuedTimers(raw_ostream &OS); 231 void printJSONValue(raw_ostream &OS, const PrintRecord &R, 232 const char *suffix, double Value); 233 }; 234 235 } // end namespace llvm 236 237 #endif 238