Commit f5df3895 authored by Kristian Høgsberg's avatar Kristian Høgsberg

Optimize wl_fixed_t to/from double conversion functions

parent fefa8c0f
......@@ -853,7 +853,7 @@ wl_closure_print(struct wl_closure *closure, struct wl_object *target, int send)
break;
case 'f':
si = (int32_t) value->uint32;
fprintf(stderr, "%f", (double) si / 256.0);
fprintf(stderr, "%f", wl_fixed_to_double(si));
break;
case 's':
fprintf(stderr, "\"%s\"", value->string);
......
......@@ -167,18 +167,32 @@ void *wl_array_add(struct wl_array *array, size_t size);
void wl_array_copy(struct wl_array *array, struct wl_array *source);
typedef int32_t wl_fixed_t;
#define WL_FIXED_INVALID_VALUE ~0L
static inline double wl_fixed_to_double(wl_fixed_t f)
static inline double
wl_fixed_to_double (wl_fixed_t f)
{
return (double) f / 256.0;
};
static inline wl_fixed_t wl_fixed_from_double(double d)
union {
double d;
int64_t i;
} u;
u.i = ((1023LL + 44LL) << 52) + (1LL << 51) + f;
return u.d - (3LL << 43);
}
static inline wl_fixed_t
wl_fixed_from_double(double d)
{
if (d >= (1 << 23))
return WL_FIXED_INVALID_VALUE;
return (wl_fixed_t) round (d * 256.0);
};
union {
double d;
int64_t i;
} u;
u.d = d + (3LL << (51 - 8));
return u.i;
}
static inline int wl_fixed_to_int(wl_fixed_t f)
{
......@@ -186,7 +200,7 @@ static inline int wl_fixed_to_int(wl_fixed_t f)
}
static inline wl_fixed_t wl_fixed_from_int(int i)
{
return wl_fixed_from_double(i);
return i * 256;
}
#ifdef __cplusplus
......
......@@ -6,12 +6,16 @@ TESTS = \
connection-test \
event-loop-test \
client-test \
os-wrappers-test
os-wrappers-test \
fixed-test
check_PROGRAMS = \
$(TESTS) \
exec-fd-leak-checker
noinst_PROGRAMS = \
fixed-benchmark
test_runner_src = test-runner.c test-runner.h test-helpers.c
sanity_test_SOURCES = sanity-test.c $(test_runner_src)
......@@ -21,6 +25,9 @@ list_test_SOURCES = list-test.c $(test_runner_src)
connection_test_SOURCES = connection-test.c $(test_runner_src)
event_loop_test_SOURCES = event-loop-test.c $(test_runner_src)
client_test_SOURCES = client-test.c $(test_runner_src)
fixed_test_SOURCES = fixed-test.c $(test_runner_src)
fixed_benchmark_SOURCES = fixed-benchmark.c
os_wrappers_test_SOURCES = \
os-wrappers-test.c \
......
/*
* 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 "../src/wayland-private.h"
volatile double global_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("magic", magic_conversion);
benchmark("div", div_conversion);
benchmark("mul", mul_conversion);
return 0;
}
/*
* 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 <assert.h>
#include "../src/wayland-private.h"
#include "test-runner.h"
TEST(fixed_double_conversions)
{
wl_fixed_t f;
double d;
d = 62.125;
f = wl_fixed_from_double(d);
fprintf(stderr, "double %lf to fixed %x\n", d, f);
assert(f == 0x3e20);
d = -1200.625;
f = wl_fixed_from_double(d);
fprintf(stderr, "double %lf to fixed %x\n", d, f);
assert(f == -0x4b0a0);
f = random();
d = wl_fixed_to_double(f);
fprintf(stderr, "fixed %x to double %lf\n", f, d);
assert(d == f / 256.0);
f = 0x012030;
d = wl_fixed_to_double(f);
fprintf(stderr, "fixed %x to double %lf\n", f, d);
assert(d == 288.1875);
f = 0x70000000;
d = wl_fixed_to_double(f);
fprintf(stderr, "fixed %x to double %lf\n", f, d);
assert(d == f / 256);
f = -0x012030;
d = wl_fixed_to_double(f);
fprintf(stderr, "fixed %x to double %lf\n", f, d);
assert(d == -288.1875);
f = 0x80000000;
d = wl_fixed_to_double(f);
fprintf(stderr, "fixed %x to double %lf\n", f, d);
assert(d == f / 256);
}
TEST(fixed_int_conversions)
{
wl_fixed_t f;
int i;
i = 62;
f = wl_fixed_from_int(i);
assert(f == 62 * 256);
i = -2080;
f = wl_fixed_from_int(i);
assert(f == -2080 * 256);
f = 0x277013;
i = wl_fixed_to_int(f);
assert(i == 0x2770);
f = -0x5044;
i = wl_fixed_to_int(f);
assert(i == -0x50);
}
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