llvm.org GIT mirror llvm / master include / llvm / ADT / Statistic.h
master

Tree @master (Download .tar.gz)

Statistic.h @master

551ccae
9769ab2
6b54768
 
 
9769ab2
b2109ce
fa10fdf
 
ac0b6ae
 
 
fa10fdf
 
 
 
ac0b6ae
fa10fdf
a0031cc
fa10fdf
ac0b6ae
 
fa10fdf
 
551ccae
 
fa10fdf
a3170b6
d0a33c4
703f12b
df71866
a3170b6
92915e3
a86576d
 
 
 
 
 
 
d0fde30
82d16ec
6ce5792
df71866
a3170b6
d0fde30
d02a34d
ecb2768
c882f76
fa10fdf
96ef1b9
fa10fdf
d02a34d
 
 
c882f76
975f058
 
d02a34d
0a36152
d02a34d
 
 
 
 
 
 
 
 
0a36152
975f058
703f12b
fa785cb
d02a34d
703f12b
92915e3
 
b35e4e8
d02a34d
703f12b
92915e3
 
b35e4e8
92915e3
 
703f12b
92915e3
b35e4e8
d02a34d
703f12b
92915e3
 
b35e4e8
92915e3
 
703f12b
92915e3
b35e4e8
d02a34d
703f12b
 
 
92915e3
 
b35e4e8
d02a34d
703f12b
 
 
92915e3
 
b35e4e8
ad0e666
 
 
 
 
 
 
 
 
 
d02a34d
 
 
 
fa785cb
 
 
d02a34d
 
fa785cb
d02a34d
 
 
fa785cb
d02a34d
fa785cb
d02a34d
 
fa785cb
d02a34d
fa785cb
d02a34d
fa785cb
d02a34d
ad0e666
d02a34d
fa785cb
d02a34d
82d16ec
d02a34d
 
 
 
 
fa10fdf
3a54b3d
d02a34d
 
 
 
 
 
ecb2768
 
703f12b
d02a34d
 
 
 
 
 
fa10fdf
26b584c
869a1fc
6ce5792
26b584c
0aa00f9
 
26b584c
df71866
 
26b584c
6ce5792
 
26b584c
6ce5792
 
9df5d1c
 
 
 
c882f76
 
26b584c
a3170b6
 
 
 
 
 
 
 
26b584c
50adb3d
 
 
 
 
 
 
 
 
 
 
 
 
 
82d16ec
d0fde30
d0a33c4
//===-- llvm/ADT/Statistic.h - Easy way to expose stats ---------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file defines the 'Statistic' class, which is designed to be an easy way
// to expose various metrics from passes.  These statistics are printed at the
// end of a run (from llvm_shutdown), when the -stats command line option is
// passed on the command line.
//
// This is useful for reporting information like the number of instructions
// simplified, optimized or removed by various transformations, like this:
//
// static Statistic NumInstsKilled("gcse", "Number of instructions killed");
//
// Later, in the code: ++NumInstsKilled;
//
// NOTE: Statistics *must* be declared as global variables.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_ADT_STATISTIC_H
#define LLVM_ADT_STATISTIC_H

#include "llvm/Config/llvm-config.h"
#include "llvm/Support/Compiler.h"
#include <atomic>
#include <memory>
#include <vector>

// Determine whether statistics should be enabled. We must do it here rather
// than in CMake because multi-config generators cannot determine this at
// configure time.
#if !defined(NDEBUG) || LLVM_FORCE_ENABLE_STATS
#define LLVM_ENABLE_STATS 1
#endif

namespace llvm {

class raw_ostream;
class raw_fd_ostream;
class StringRef;

class StatisticBase {
public:
  const char *DebugType;
  const char *Name;
  const char *Desc;

  StatisticBase(const char *DebugType, const char *Name, const char *Desc)
      : DebugType(DebugType), Name(Name), Desc(Desc) {}

  const char *getDebugType() const { return DebugType; }
  const char *getName() const { return Name; }
  const char *getDesc() const { return Desc; }
};

class TrackingStatistic : public StatisticBase {
public:
  std::atomic<unsigned> Value;
  std::atomic<bool> Initialized;

  TrackingStatistic(const char *DebugType, const char *Name, const char *Desc)
      : StatisticBase(DebugType, Name, Desc), Value(0), Initialized(false) {}

  unsigned getValue() const { return Value.load(std::memory_order_relaxed); }

  // Allow use of this class as the value itself.
  operator unsigned() const { return getValue(); }

  const TrackingStatistic &operator=(unsigned Val) {
    Value.store(Val, std::memory_order_relaxed);
    return init();
  }

  const TrackingStatistic &operator++() {
    Value.fetch_add(1, std::memory_order_relaxed);
    return init();
  }

  unsigned operator++(int) {
    init();
    return Value.fetch_add(1, std::memory_order_relaxed);
  }

  const TrackingStatistic &operator--() {
    Value.fetch_sub(1, std::memory_order_relaxed);
    return init();
  }

  unsigned operator--(int) {
    init();
    return Value.fetch_sub(1, std::memory_order_relaxed);
  }

  const TrackingStatistic &operator+=(unsigned V) {
    if (V == 0)
      return *this;
    Value.fetch_add(V, std::memory_order_relaxed);
    return init();
  }

  const TrackingStatistic &operator-=(unsigned V) {
    if (V == 0)
      return *this;
    Value.fetch_sub(V, std::memory_order_relaxed);
    return init();
  }

  void updateMax(unsigned V) {
    unsigned PrevMax = Value.load(std::memory_order_relaxed);
    // Keep trying to update max until we succeed or another thread produces
    // a bigger max than us.
    while (V > PrevMax && !Value.compare_exchange_weak(
                              PrevMax, V, std::memory_order_relaxed)) {
    }
    init();
  }

protected:
  TrackingStatistic &init() {
    if (!Initialized.load(std::memory_order_acquire))
      RegisterStatistic();
    return *this;
  }

  void RegisterStatistic();
};

class NoopStatistic : public StatisticBase {
public:
  using StatisticBase::StatisticBase;

  unsigned getValue() const { return 0; }

  // Allow use of this class as the value itself.
  operator unsigned() const { return 0; }

  const NoopStatistic &operator=(unsigned Val) { return *this; }

  const NoopStatistic &operator++() { return *this; }

  unsigned operator++(int) { return 0; }

  const NoopStatistic &operator--() { return *this; }

  unsigned operator--(int) { return 0; }

  const NoopStatistic &operator+=(const unsigned &V) { return *this; }

  const NoopStatistic &operator-=(const unsigned &V) { return *this; }

  void updateMax(unsigned V) {}
};

#if LLVM_ENABLE_STATS
using Statistic = TrackingStatistic;
#else
using Statistic = NoopStatistic;
#endif

// STATISTIC - A macro to make definition of statistics really simple.  This
// automatically passes the DEBUG_TYPE of the file into the statistic.
#define STATISTIC(VARNAME, DESC)                                               \
  static llvm::Statistic VARNAME = {DEBUG_TYPE, #VARNAME, DESC}

// ALWAYS_ENABLED_STATISTIC - A macro to define a statistic like STATISTIC but
// it is enabled even if LLVM_ENABLE_STATS is off.
#define ALWAYS_ENABLED_STATISTIC(VARNAME, DESC)                                \
  static llvm::TrackingStatistic VARNAME = {DEBUG_TYPE, #VARNAME, DESC}

/// Enable the collection and printing of statistics.
void EnableStatistics(bool PrintOnExit = true);

/// Check if statistics are enabled.
bool AreStatisticsEnabled();

/// Return a file stream to print our output on.
std::unique_ptr<raw_fd_ostream> CreateInfoOutputFile();

/// Print statistics to the file returned by CreateInfoOutputFile().
void PrintStatistics();

/// Print statistics to the given output stream.
void PrintStatistics(raw_ostream &OS);

/// Print statistics in JSON format. This does include all global timers (\see
/// Timer, TimerGroup). Note that the timers are cleared after printing and will
/// not be printed in human readable form or in a second call of
/// PrintStatisticsJSON().
void PrintStatisticsJSON(raw_ostream &OS);

/// Get the statistics. This can be used to look up the value of
/// statistics without needing to parse JSON.
///
/// This function does not prevent statistics being updated by other threads
/// during it's execution. It will return the value at the point that it is
/// read. However, it will prevent new statistics from registering until it
/// completes.
const std::vector<std::pair<StringRef, unsigned>> GetStatistics();

/// Reset the statistics. This can be used to zero and de-register the
/// statistics in order to measure a compilation.
///
/// When this function begins to call destructors prior to returning, all
/// statistics will be zero and unregistered. However, that might not remain the
/// case by the time this function finishes returning. Whether update from other
/// threads are lost or merely deferred until during the function return is
/// timing sensitive.
///
/// Callers who intend to use this to measure statistics for a single
/// compilation should ensure that no compilations are in progress at the point
/// this function is called and that only one compilation executes until calling
/// GetStatistics().
void ResetStatistics();

} // end namespace llvm

#endif // LLVM_ADT_STATISTIC_H