131 lines · cpp
1/** @file kmp_stats_timing.cpp2 * Timing functions3 */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-exception10//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_TIME26#if KMP_MIC27double tsc_tick_count::tick_time() {28 // pretty bad assumption of 1GHz clock for MIC29 return 1 / ((double)1000 * 1.e6);30}31#elif KMP_ARCH_X86 || KMP_ARCH_X86_6432#include <string.h>33// Extract the value from the CPUID information34double 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#endif82#endif83 84static bool useSI = true;85 86// Return a formatted string after normalising the value into87// 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 the93 // positive powers of ten are precisely representable.94 static struct {95 double scale;96 char prefix;97 } ranges[] = {{1.e21, 'y'}, {1.e18, 'z'}, {1.e15, 'a'}, {1.e12, 'f'},98 {1.e9, 'p'}, {1.e6, 'n'}, {1.e3, 'u'}, {1.0, 'm'},99 {1.e-3, ' '}, {1.e-6, 'k'}, {1.e-9, 'M'}, {1.e-12, 'G'},100 {1.e-15, 'T'}, {1.e-18, 'P'}, {1.e-21, 'E'}, {1.e-24, 'Z'},101 {1.e-27, '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