mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-30 00:31:08 +00:00
98 lines
2.4 KiB
C
98 lines
2.4 KiB
C
/* Compute sine of argument.
|
|
Copyright (C) 2018-2023 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
#include <stdint.h>
|
|
#include <math.h>
|
|
#include <math-barriers.h>
|
|
#include <libm-alias-float.h>
|
|
#include "math_config.h"
|
|
#include "s_sincosf.h"
|
|
|
|
#ifndef SECTION
|
|
# define SECTION
|
|
#endif
|
|
|
|
#ifndef SINF
|
|
# define SINF_FUNC __sinf
|
|
#else
|
|
# define SINF_FUNC SINF
|
|
#endif
|
|
|
|
/* Fast sinf implementation. Worst-case ULP is 0.5607, maximum relative
|
|
error is 0.5303 * 2^-23. A single-step range reduction is used for
|
|
small values. Large inputs have their range reduced using fast integer
|
|
arithmetic.
|
|
*/
|
|
float
|
|
SECTION
|
|
SINF_FUNC (float y)
|
|
{
|
|
double x = y;
|
|
double s;
|
|
int n;
|
|
const sincos_t *p = &__sincosf_table[0];
|
|
|
|
if (abstop12 (y) < abstop12 (pio4))
|
|
{
|
|
s = x * x;
|
|
|
|
if (__glibc_unlikely (abstop12 (y) < abstop12 (0x1p-12f)))
|
|
{
|
|
/* Force underflow for tiny y. */
|
|
if (__glibc_unlikely (abstop12 (y) < abstop12 (0x1p-126f)))
|
|
math_force_eval ((float)s);
|
|
return y;
|
|
}
|
|
|
|
return sinf_poly (x, s, p, 0);
|
|
}
|
|
else if (__glibc_likely (abstop12 (y) < abstop12 (120.0f)))
|
|
{
|
|
x = reduce_fast (x, p, &n);
|
|
|
|
/* Setup the signs for sin and cos. */
|
|
s = p->sign[n & 3];
|
|
|
|
if (n & 2)
|
|
p = &__sincosf_table[1];
|
|
|
|
return sinf_poly (x * s, x * x, p, n);
|
|
}
|
|
else if (abstop12 (y) < abstop12 (INFINITY))
|
|
{
|
|
uint32_t xi = asuint (y);
|
|
int sign = xi >> 31;
|
|
|
|
x = reduce_large (xi, &n);
|
|
|
|
/* Setup signs for sin and cos - include original sign. */
|
|
s = p->sign[(n + sign) & 3];
|
|
|
|
if ((n + sign) & 2)
|
|
p = &__sincosf_table[1];
|
|
|
|
return sinf_poly (x * s, x * x, p, n);
|
|
}
|
|
else
|
|
return __math_invalidf (y);
|
|
}
|
|
|
|
#ifndef SINF
|
|
libm_alias_float (__sin, sin)
|
|
#endif
|