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/*-
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
/* s_sincosf.c -- float version of s_sincos.c.
* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
* Optimized by Bruce D. Evans.
* Merged s_sinf.c and s_cosf.c by Steven G. Kargl.
*/
#include <float.h>
#include "math.h"
#include "math_private.h"
#include "k_sincosf.h"
/* Small multiples of pi/2 rounded to double precision. */
static const double
p1pio2 = 1*M_PI_2, /* 0x3FF921FB, 0x54442D18 */
p2pio2 = 2*M_PI_2, /* 0x400921FB, 0x54442D18 */
p3pio2 = 3*M_PI_2, /* 0x4012D97C, 0x7F3321D2 */
p4pio2 = 4*M_PI_2; /* 0x401921FB, 0x54442D18 */
void
sincosf(float x, float *sn, float *cs)
{
float c, s;
float y[2];
int32_t n, hx, ix;
GET_FLOAT_WORD(hx, x);
ix = hx & 0x7fffffff;
if (ix <= 0x3f490fda) { /* |x| ~<= pi/4 */
if (ix < 0x39800000) { /* |x| < 2**-12 */
if ((int)x == 0) {
*sn = x; /* x with inexact if x != 0 */
*cs = 1;
return;
}
}
__kernel_sincosdf(x, sn, cs);
return;
}
if (ix <= 0x407b53d1) { /* |x| ~<= 5*pi/4 */
if (ix <= 0x4016cbe3) { /* |x| ~<= 3pi/4 */
if (hx > 0) {
__kernel_sincosdf(x - p1pio2, cs, sn);
*cs = -*cs;
} else {
__kernel_sincosdf(x + p1pio2, cs, sn);
*sn = -*sn;
}
} else {
if (hx > 0)
__kernel_sincosdf(x - p2pio2, sn, cs);
else
__kernel_sincosdf(x + p2pio2, sn, cs);
*sn = -*sn;
*cs = -*cs;
}
return;
}
if (ix <= 0x40e231d5) { /* |x| ~<= 9*pi/4 */
if (ix <= 0x40afeddf) { /* |x| ~<= 7*pi/4 */
if (hx > 0) {
__kernel_sincosdf(x - p3pio2, cs, sn);
*sn = -*sn;
} else {
__kernel_sincosdf(x + p3pio2, cs, sn);
*cs = -*cs;
}
} else {
if (hx > 0)
__kernel_sincosdf(x - p4pio2, sn, cs);
else
__kernel_sincosdf(x + p4pio2, sn, cs);
}
return;
}
/* If x = Inf or NaN, then sin(x) = NaN and cos(x) = NaN. */
if (ix >= 0x7f800000) {
*sn = x - x;
*cs = x - x;
return;
}
/* Argument reduction. */
n = __ieee754_rem_pio2f(x, y);
s = __kernel_sinf(y[0], y[1], 1);
c = __kernel_cosf(y[0], y[1]);
switch(n & 3) {
case 0:
*sn = s;
*cs = c;
break;
case 1:
*sn = c;
*cs = -s;
break;
case 2:
*sn = -s;
*cs = -c;
break;
default:
*sn = -c;
*cs = s;
}
}
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