/*
* Copyright © 2015 Kazunobu Kuriyama <kazunobu.kuriyama@nifty.com>
* Copyright © 2015 Ran Benita <ran234@gmail.com>
* SPDX-License-Identifier: MIT
*/
#include "config.h"
#include <assert.h>
#include <stdio.h>
#include <math.h>
#include "bench.h"
#include "../src/utils.h"
#ifndef _WIN32
#include <time.h>
#include <sys/time.h>
#else
#include <windows.h>
#include <stdint.h>
struct timeval {
long tv_sec, tv_usec;
};
static int
gettimeofday(struct timeval *tv, void *unused)
{
static const uint64_t EPOCH = ((uint64_t) 116444736000000000ULL);
SYSTEMTIME system_time;
FILETIME file_time;
uint64_t t;
GetSystemTime(&system_time);
SystemTimeToFileTime(&system_time, &file_time);
t = (uint64_t) file_time.dwLowDateTime;
t += ((uint64_t) file_time.dwHighDateTime) << 32;
tv->tv_sec = (long) ((t - EPOCH) / 10000000L);
tv->tv_usec = (long) (system_time.wMilliseconds * 1000);
return 0;
}
#endif
void
bench_start(struct bench *bench)
{
struct timeval val;
(void) gettimeofday(&val, NULL);
bench->start = (struct bench_time) {
.seconds = val.tv_sec,
.nanoseconds = val.tv_usec * 1000,
};
}
void
bench_stop(struct bench *bench)
{
struct timeval val;
(void) gettimeofday(&val, NULL);
bench->stop = (struct bench_time) {
.seconds = val.tv_sec,
.nanoseconds = val.tv_usec * 1000,
};
}
#ifndef _WIN32
void
bench_start2(struct bench *bench)
{
struct timespec t;
(void) clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &t);
// (void) clock_gettime(CLOCK_MONOTONIC, &t);
bench->start = (struct bench_time) {
.seconds = t.tv_sec,
.nanoseconds = t.tv_nsec,
};
}
void
bench_stop2(struct bench *bench)
{
struct timespec t;
(void) clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &t);
// (void) clock_gettime(CLOCK_MONOTONIC, &t);
bench->stop = (struct bench_time) {
.seconds = t.tv_sec,
.nanoseconds = t.tv_nsec,
};
}
#endif
void
bench_elapsed(const struct bench *bench, struct bench_time *result)
{
result->seconds = bench->stop.seconds - bench->start.seconds;
result->nanoseconds = bench->stop.nanoseconds - bench->start.nanoseconds;
if (result->nanoseconds < 0) {
result->nanoseconds += 1000000000;
result->seconds--;
}
}
char *
bench_elapsed_str(const struct bench *bench)
{
struct bench_time elapsed;
char *buf;
int ret;
bench_elapsed(bench, &elapsed);
ret = asprintf(&buf, "%ld.%06ld", elapsed.seconds, elapsed.nanoseconds / 1000);
assert(ret >= 0);
return buf;
}
/* Utils for bench method adapted from: https://hackage.haskell.org/package/tasty-bench */
#define fit(x1, x2) ((x1) / 5 + 2 * ((x2) / 5))
#define sqr(x) ((x) * (x))
static void
predict(long long t1, long long t2, struct estimate *est)
{
const long long t = fit(t1, t2);
est->elapsed = t;
est->stdev =
llroundl(sqrtl((long double)sqr(t1 - t) + (long double)sqr(t2 - 2 * t)));
}
#define high(t, prec) ((t) + (prec))
#define low(t, prec) ((t) - (prec))
#define MIN_PRECISION 1000000 /* 1ms */
void
predictPerturbed(const struct bench_time *b1, const struct bench_time *b2,
struct estimate *est)
{
const long long t1 = bench_time_elapsed_nanoseconds(b1);
const long long t2 = bench_time_elapsed_nanoseconds(b2);
#ifndef _WIN32
struct timespec ts;
(void) clock_getres(CLOCK_PROCESS_CPUTIME_ID, &ts);
long long precision = MAX(ts.tv_sec * 1000000000 + ts.tv_nsec, MIN_PRECISION);
#else
long long precision = MIN_PRECISION;
#endif
struct estimate est1;
struct estimate est2;
predict(t1, t2, est);
predict(low(t1, precision), high(t2, precision), &est1);
predict(high(t1, precision), low(t2, precision), &est2);
est->stdev = MAX(est1.stdev, est2.stdev);
}