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//===-- 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.
#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)
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.
explicit Timer(StringRef N) : TG(nullptr) { init(N); }
Timer(StringRef N, TimerGroup &tg) : TG(nullptr) { init(N, tg); }
Timer(const Timer &RHS) : TG(nullptr) {
assert(!RHS.TG && "Can only copy uninitialized timers");
const Timer &operator=(const Timer &T) {
assert(!TG && !T.TG && "Can only assign uninit timers");
return *this;
// Create an uninitialized timer, client must use 'init'.
explicit Timer() : TG(nullptr) {}
void init(StringRef N);
void init(StringRef N, TimerGroup &tg);
const std::string &getName() const { return Name; }
bool isInitialized() const { return TG != nullptr; }
/// 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();
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;
explicit TimeRegion(Timer &t) : T(&t) {
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;
explicit TimerGroup(StringRef name);
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);
friend class Timer;
void addTimer(Timer &T);
void removeTimer(Timer &T);
void PrintQueuedTimers(raw_ostream &OS);
} // End llvm namespace