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/*
* Copyright © 2012 Intel Corporation
*
* Permission to use, copy, modify, distribute, and sell this software and its
* documentation for any purpose is hereby granted without fee, provided that
* the above copyright notice appear in all copies and that both that copyright
* notice and this permission notice appear in supporting documentation, and
* that the name of the copyright holders not be used in advertising or
* publicity pertaining to distribution of the software without specific,
* written prior permission. The copyright holders make no representations
* about the suitability of this software for any purpose. It is provided "as
* is" without express or implied warranty.
*
* THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
* INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
* EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
* CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
* DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
* TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
* OF THIS SOFTWARE.
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <time.h>
#include <assert.h>
#include "wayland-private.h"
volatile double global_d;
static void
noop_conversion(void)
{
wl_fixed_t f;
union {
int64_t i;
double d;
} u;
for (f = 0; f < INT32_MAX; f++) {
u.i = f;
global_d = u.d;
}
}
static void
magic_conversion(void)
{
wl_fixed_t f;
for (f = 0; f < INT32_MAX; f++)
global_d = wl_fixed_to_double(f);
}
static void
mul_conversion(void)
{
wl_fixed_t f;
/* This will get optimized into multiplication by 1/256 */
for (f = 0; f < INT32_MAX; f++)
global_d = f / 256.0;
}
double factor = 256.0;
static void
div_conversion(void)
{
wl_fixed_t f;
for (f = 0; f < INT32_MAX; f++)
global_d = f / factor;
}
static void
benchmark(const char *s, void (*f)(void))
{
struct timespec start, stop, elapsed;
clock_gettime(CLOCK_MONOTONIC, &start);
f();
clock_gettime(CLOCK_MONOTONIC, &stop);
elapsed.tv_sec = stop.tv_sec - start.tv_sec;
elapsed.tv_nsec = stop.tv_nsec - start.tv_nsec;
if (elapsed.tv_nsec < 0) {
elapsed.tv_nsec += 1000000000;
elapsed.tv_sec--;
}
printf("benchmarked %s:\t%ld.%09lds\n",
s, elapsed.tv_sec, elapsed.tv_nsec);
}
int main(int argc, char *argv[])
{
benchmark("noop", noop_conversion);
benchmark("magic", magic_conversion);
benchmark("div", div_conversion);
benchmark("mul", mul_conversion);
return 0;
}
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