LLVM OpenMP* Runtime Library
kmp_stats_timing.h
1 #ifndef KMP_STATS_TIMING_H
2 #define KMP_STATS_TIMING_H
3 
8 //===----------------------------------------------------------------------===//
9 //
10 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
11 // See https://llvm.org/LICENSE.txt for license information.
12 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
13 //
14 //===----------------------------------------------------------------------===//
15 
16 #include "kmp_os.h"
17 #include <limits>
18 #include <stdint.h>
19 #include <string>
20 #if KMP_HAVE_X86INTRIN_H
21 #include <x86intrin.h>
22 #endif
23 
24 class tsc_tick_count {
25 private:
26  int64_t my_count;
27 
28 public:
29  class tsc_interval_t {
30  int64_t value;
31  explicit tsc_interval_t(int64_t _value) : value(_value) {}
32 
33  public:
34  tsc_interval_t() : value(0) {} // Construct 0 time duration
35 #if KMP_HAVE_TICK_TIME
36  double seconds() const; // Return the length of a time interval in seconds
37 #endif
38  double ticks() const { return double(value); }
39  int64_t getValue() const { return value; }
40  tsc_interval_t &operator=(int64_t nvalue) {
41  value = nvalue;
42  return *this;
43  }
44 
45  friend class tsc_tick_count;
46 
47  friend tsc_interval_t operator-(const tsc_tick_count &t1,
48  const tsc_tick_count &t0);
49  friend tsc_interval_t operator-(const tsc_tick_count::tsc_interval_t &i1,
50  const tsc_tick_count::tsc_interval_t &i0);
51  friend tsc_interval_t &operator+=(tsc_tick_count::tsc_interval_t &i1,
52  const tsc_tick_count::tsc_interval_t &i0);
53  };
54 
55 #if KMP_HAVE___BUILTIN_READCYCLECOUNTER
56  tsc_tick_count()
57  : my_count(static_cast<int64_t>(__builtin_readcyclecounter())) {}
58 #elif KMP_HAVE___RDTSC
59  tsc_tick_count() : my_count(static_cast<int64_t>(__rdtsc())) {}
60 #else
61 #error Must have high resolution timer defined
62 #endif
63  tsc_tick_count(int64_t value) : my_count(value) {}
64  int64_t getValue() const { return my_count; }
65  tsc_tick_count later(tsc_tick_count const other) const {
66  return my_count > other.my_count ? (*this) : other;
67  }
68  tsc_tick_count earlier(tsc_tick_count const other) const {
69  return my_count < other.my_count ? (*this) : other;
70  }
71 #if KMP_HAVE_TICK_TIME
72  static double tick_time(); // returns seconds per cycle (period) of clock
73 #endif
74  static tsc_tick_count now() {
75  return tsc_tick_count();
76  } // returns the rdtsc register value
77  friend tsc_tick_count::tsc_interval_t operator-(const tsc_tick_count &t1,
78  const tsc_tick_count &t0);
79 };
80 
81 inline tsc_tick_count::tsc_interval_t operator-(const tsc_tick_count &t1,
82  const tsc_tick_count &t0) {
83  return tsc_tick_count::tsc_interval_t(t1.my_count - t0.my_count);
84 }
85 
86 inline tsc_tick_count::tsc_interval_t
87 operator-(const tsc_tick_count::tsc_interval_t &i1,
88  const tsc_tick_count::tsc_interval_t &i0) {
89  return tsc_tick_count::tsc_interval_t(i1.value - i0.value);
90 }
91 
92 inline tsc_tick_count::tsc_interval_t &
93 operator+=(tsc_tick_count::tsc_interval_t &i1,
94  const tsc_tick_count::tsc_interval_t &i0) {
95  i1.value += i0.value;
96  return i1;
97 }
98 
99 #if KMP_HAVE_TICK_TIME
100 inline double tsc_tick_count::tsc_interval_t::seconds() const {
101  return value * tick_time();
102 }
103 #endif
104 
105 extern std::string formatSI(double interval, int width, char unit);
106 
107 inline std::string formatSeconds(double interval, int width) {
108  return formatSI(interval, width, 'S');
109 }
110 
111 inline std::string formatTicks(double interval, int width) {
112  return formatSI(interval, width, 'T');
113 }
114 
115 #endif // KMP_STATS_TIMING_H