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/* s_sinf.c -- float version of s_sin.c.
* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
* Optimized by Bruce D. Evans.
*/
/*
* ====================================================
* 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.
* ====================================================
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "math.h"
#define INLINE_KERNEL_COSDF
#define INLINE_KERNEL_SINDF
#include "math_private.h"
#include "k_cosf.c"
#include "k_sinf.c"
/* Small multiples of pi/2 rounded to double precision. */
static const double
s1pio2 = 1*M_PI_2, /* 0x3FF921FB, 0x54442D18 */
s2pio2 = 2*M_PI_2, /* 0x400921FB, 0x54442D18 */
s3pio2 = 3*M_PI_2, /* 0x4012D97C, 0x7F3321D2 */
s4pio2 = 4*M_PI_2; /* 0x401921FB, 0x54442D18 */
float
sinf(float x)
{
double y;
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) return x; /* x with inexact if x != 0 */
return __kernel_sindf(x);
}
if(ix<=0x407b53d1) { /* |x| ~<= 5*pi/4 */
if(ix<=0x4016cbe3) { /* |x| ~<= 3pi/4 */
if(hx>0)
return __kernel_cosdf(x - s1pio2);
else
return -__kernel_cosdf(x + s1pio2);
} else
return __kernel_sindf((hx > 0 ? s2pio2 : -s2pio2) - x);
}
if(ix<=0x40e231d5) { /* |x| ~<= 9*pi/4 */
if(ix<=0x40afeddf) { /* |x| ~<= 7*pi/4 */
if(hx>0)
return -__kernel_cosdf(x - s3pio2);
else
return __kernel_cosdf(x + s3pio2);
} else
return __kernel_sindf(x + (hx > 0 ? -s4pio2 : s4pio2));
}
/* sin(Inf or NaN) is NaN */
else if (ix>=0x7f800000) return x-x;
/* general argument reduction needed */
else {
n = __ieee754_rem_pio2f(x,&y);
switch(n&3) {
case 0: return __kernel_sindf(y);
case 1: return __kernel_cosdf(y);
case 2: return __kernel_sindf(-y);
default:
return -__kernel_cosdf(y);
}
}
}
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