1 //===-- llvm/ADT/Statistic.h - Easy way to expose stats ---------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines the 'Statistic' class, which is designed to be an easy way
11 // to expose various metrics from passes. These statistics are printed at the
12 // end of a run (from llvm_shutdown), when the -stats command line option is
13 // passed on the command line.
15 // This is useful for reporting information like the number of instructions
16 // simplified, optimized or removed by various transformations, like this:
18 // static Statistic NumInstsKilled("gcse", "Number of instructions killed");
20 // Later, in the code: ++NumInstsKilled;
22 // NOTE: Statistics *must* be declared as global variables.
24 //===----------------------------------------------------------------------===//
26 #ifndef LLVM_ADT_STATISTIC_H
27 #define LLVM_ADT_STATISTIC_H
29 #include "llvm/System/Atomic.h"
37 volatile llvm::sys::cas_flag Value;
40 llvm::sys::cas_flag getValue() const { return Value; }
41 const char *getName() const { return Name; }
42 const char *getDesc() const { return Desc; }
44 /// construct - This should only be called for non-global statistics.
45 void construct(const char *name, const char *desc) {
46 Name = name; Desc = desc;
47 Value = 0; Initialized = 0;
50 // Allow use of this class as the value itself.
51 operator unsigned() const { return Value; }
52 const Statistic &operator=(unsigned Val) {
57 const Statistic &operator++() {
58 sys::AtomicIncrement(&Value);
62 unsigned operator++(int) {
64 unsigned OldValue = Value;
65 sys::AtomicIncrement(&Value);
69 const Statistic &operator--() {
70 sys::AtomicDecrement(&Value);
74 unsigned operator--(int) {
76 unsigned OldValue = Value;
77 sys::AtomicDecrement(&Value);
81 const Statistic &operator+=(const unsigned &V) {
82 sys::AtomicAdd(&Value, V);
86 const Statistic &operator-=(const unsigned &V) {
87 sys::AtomicAdd(&Value, -V);
91 const Statistic &operator*=(const unsigned &V) {
92 sys::AtomicMul(&Value, V);
96 const Statistic &operator/=(const unsigned &V) {
97 sys::AtomicDiv(&Value, V);
103 bool tmp = Initialized;
105 if (!tmp) RegisterStatistic();
108 void RegisterStatistic();
111 // STATISTIC - A macro to make definition of statistics really simple. This
112 // automatically passes the DEBUG_TYPE of the file into the statistic.
113 #define STATISTIC(VARNAME, DESC) \
114 static llvm::Statistic VARNAME = { DEBUG_TYPE, DESC, 0, 0 }
116 } // End llvm namespace