1/** @file kmp_stats_timing.cpp
2 * Timing functions
3 */
4
5//===----------------------------------------------------------------------===//
6//
7// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
8// See https://llvm.org/LICENSE.txt for license information.
9// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
10//
11//===----------------------------------------------------------------------===//
12
13#include <stdlib.h>
14#include <unistd.h>
15
16#include <iomanip>
17#include <iostream>
18#include <sstream>
19
20#include "kmp.h"
21#include "kmp_stats_timing.h"
22
23using namespace std;
24
25#if KMP_HAVE_TICK_TIME
26#if KMP_MIC
27double tsc_tick_count::tick_time() {
28 // pretty bad assumption of 1GHz clock for MIC
29 return 1 / ((double)1000 * 1.e6);
30}
31#elif KMP_ARCH_X86 || KMP_ARCH_X86_64
32#include <string.h>
33// Extract the value from the CPUID information
34double tsc_tick_count::tick_time() {
35 static double result = 0.0;
36
37 if (result == 0.0) {
38 kmp_cpuid_t cpuinfo;
39 char brand[256];
40
41 __kmp_x86_cpuid(0x80000000, 0, &cpuinfo);
42 memset(brand, 0, sizeof(brand));
43 int ids = cpuinfo.eax;
44
45 for (unsigned int i = 2; i < (ids ^ 0x80000000) + 2; i++)
46 __kmp_x86_cpuid(i | 0x80000000, 0,
47 (kmp_cpuid_t *)(brand + (i - 2) * sizeof(kmp_cpuid_t)));
48
49 char *start = &brand[0];
50 for (; *start == ' '; start++)
51 ;
52
53 char *end = brand + KMP_STRLEN(brand) - 3;
54 uint64_t multiplier;
55
56 if (*end == 'M')
57 multiplier = 1000LL * 1000LL;
58 else if (*end == 'G')
59 multiplier = 1000LL * 1000LL * 1000LL;
60 else if (*end == 'T')
61 multiplier = 1000LL * 1000LL * 1000LL * 1000LL;
62 else {
63 cout << "Error determining multiplier '" << *end << "'\n";
64 exit(-1);
65 }
66 *end = 0;
67 while (*end != ' ')
68 end--;
69 end++;
70
71 double freq = strtod(end, &start);
72 if (freq == 0.0) {
73 cout << "Error calculating frequency " << end << "\n";
74 exit(-1);
75 }
76
77 result = ((double)1.0) / (freq * multiplier);
78 }
79 return result;
80}
81#endif
82#endif
83
84static bool useSI = true;
85
86// Return a formatted string after normalising the value into
87// engineering style and using a suitable unit prefix (e.g. ms, us, ns).
88std::string formatSI(double interval, int width, char unit) {
89 std::stringstream os;
90
91 if (useSI) {
92 // Preserve accuracy for small numbers, since we only multiply and the
93 // positive powers of ten are precisely representable.
94 static struct {
95 double scale;
96 char prefix;
97 } ranges[] = {{.scale: 1.e21, .prefix: 'y'}, {.scale: 1.e18, .prefix: 'z'}, {.scale: 1.e15, .prefix: 'a'}, {.scale: 1.e12, .prefix: 'f'},
98 {.scale: 1.e9, .prefix: 'p'}, {.scale: 1.e6, .prefix: 'n'}, {.scale: 1.e3, .prefix: 'u'}, {.scale: 1.0, .prefix: 'm'},
99 {.scale: 1.e-3, .prefix: ' '}, {.scale: 1.e-6, .prefix: 'k'}, {.scale: 1.e-9, .prefix: 'M'}, {.scale: 1.e-12, .prefix: 'G'},
100 {.scale: 1.e-15, .prefix: 'T'}, {.scale: 1.e-18, .prefix: 'P'}, {.scale: 1.e-21, .prefix: 'E'}, {.scale: 1.e-24, .prefix: 'Z'},
101 {.scale: 1.e-27, .prefix: 'Y'}};
102
103 if (interval == 0.0) {
104 os << std::setw(width - 3) << std::right << "0.00" << std::setw(3)
105 << unit;
106 return os.str();
107 }
108
109 bool negative = false;
110 if (interval < 0.0) {
111 negative = true;
112 interval = -interval;
113 }
114
115 for (int i = 0; i < (int)(sizeof(ranges) / sizeof(ranges[0])); i++) {
116 if (interval * ranges[i].scale < 1.e0) {
117 interval = interval * 1000.e0 * ranges[i].scale;
118 os << std::fixed << std::setprecision(2) << std::setw(width - 3)
119 << std::right << (negative ? -interval : interval) << std::setw(2)
120 << ranges[i].prefix << std::setw(1) << unit;
121
122 return os.str();
123 }
124 }
125 }
126 os << std::setprecision(2) << std::fixed << std::right << std::setw(width - 3)
127 << interval << std::setw(3) << unit;
128
129 return os.str();
130}
131

source code of openmp/runtime/src/kmp_stats_timing.cpp