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/*
* Single-precision sin/cos function.
*
* Copyright (c) 2018-2019, Arm Limited.
* SPDX-License-Identifier: MIT
*/
#include <stdint.h>
#include <math.h>
#include "math_config.h"
#include "sincosf.h"
/* Fast sincosf 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. */
void
sincosf (float y, float *sinp, float *cosp)
{
double x = y;
double s;
int n;
const sincos_t *p = &__sincosf_table[0];
if (abstop12 (y) < abstop12 (pio4))
{
double x2 = x * x;
if (unlikely (abstop12 (y) < abstop12 (0x1p-12f)))
{
if (unlikely (abstop12 (y) < abstop12 (0x1p-126f)))
/* Force underflow for tiny y. */
force_eval_float (x2);
*sinp = y;
*cosp = 1.0f;
return;
}
sincosf_poly (x, x2, p, 0, sinp, cosp);
}
else if (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];
sincosf_poly (x * s, x * x, p, n, sinp, cosp);
}
else if (likely (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];
sincosf_poly (x * s, x * x, p, n, sinp, cosp);
}
else
{
/* Return NaN if Inf or NaN for both sin and cos. */
*sinp = *cosp = y - y;
#if WANT_ERRNO
/* Needed to set errno for +-Inf, the add is a hack to work
around a gcc register allocation issue: just passing y
affects code generation in the fast path. */
__math_invalidf (y + y);
#endif
}
}
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