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/*
* Fused Multiply Add (Single)
*
* Copyright (c) 2019 Linaro
*
* SPDX-License-Identifier: GPL-3.0-or-later
*/
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <float.h>
#include <fenv.h>
#include "float_helpers.h"
#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
typedef struct {
int flag;
char *desc;
} float_mapping;
float_mapping round_flags[] = {
{ FE_TONEAREST, "to nearest" },
#ifdef FE_UPWARD
{ FE_UPWARD, "upwards" },
#endif
#ifdef FE_DOWNWARD
{ FE_DOWNWARD, "downwards" },
#endif
{ FE_TOWARDZERO, "to zero" }
};
static void print_inputs(float a, float b, float c)
{
char *a_fmt, *b_fmt, *c_fmt;
a_fmt = fmt_f32(a);
b_fmt = fmt_f32(b);
c_fmt = fmt_f32(c);
printf("op : %s * %s + %s\n", a_fmt, b_fmt, c_fmt);
free(a_fmt);
free(b_fmt);
free(c_fmt);
}
static void print_result(float r, int j, int k)
{
char *r_fmt, *flag_fmt;
r_fmt = fmt_f32(r);
flag_fmt = fmt_flags();
printf("res: %s flags=%s (%d/%d)\n", r_fmt, flag_fmt, j, k);
free(r_fmt);
free(flag_fmt);
}
static void do_madds(float a, float b, float c, int j, int k)
{
float r;
print_inputs(a, b, c);
feclearexcept(FE_ALL_EXCEPT);
r = __builtin_fmaf(a, b, c);
print_result(r, j, k);
}
int main(int argc, char *argv[argc])
{
int i, j, k, nums = get_num_f32();
float a, b, c;
for (i = 0; i < ARRAY_SIZE(round_flags); ++i) {
if (fesetround(round_flags[i].flag) != 0) {
printf("### Rounding %s skipped\n", round_flags[i].desc);
continue;
}
printf("### Rounding %s\n", round_flags[i].desc);
for (j = 0; j < nums; j++) {
for (k = 0; k < 3; k++) {
a = get_f32(j + ((k)%3));
b = get_f32(j + ((k+1)%3));
c = get_f32(j + ((k+2)%3));
do_madds(a, b, c, j, k);
}
}
/* From https://bugs.launchpad.net/qemu/+bug/1841491 */
printf("# LP184149\n");
do_madds(0x1.ffffffffffffcp-1022, 0x1.0000000000001p-1, 0x0.0000000000001p-1022, j, 0);
do_madds(0x8p-152, 0x8p-152, 0x8p-152, j+1, 0);
}
return 0;
}
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