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/* s_cosf.c -- float version of s_cos.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 <float.h>
#define INLINE_KERNEL_COSDF
#define INLINE_KERNEL_SINDF
#define INLINE_REM_PIO2F
#include "math_private.h"
#include "e_rem_pio2f.cpp"
#include "k_cosf.cpp"
#include "k_sinf.cpp"
/* Small multiples of pi/2 rounded to double precision. */
static const double
c1pio2 = 1*M_PI_2, /* 0x3FF921FB, 0x54442D18 */
c2pio2 = 2*M_PI_2, /* 0x400921FB, 0x54442D18 */
c3pio2 = 3*M_PI_2, /* 0x4012D97C, 0x7F3321D2 */
c4pio2 = 4*M_PI_2; /* 0x401921FB, 0x54442D18 */
float
cosf(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 1.0; /* 1 with inexact if x != 0 */
return __kernel_cosdf(x);
}
if(ix<=0x407b53d1) { /* |x| ~<= 5*pi/4 */
if(ix>0x4016cbe3) /* |x| ~> 3*pi/4 */
return -__kernel_cosdf(x + (hx > 0 ? -c2pio2 : c2pio2));
else {
if(hx>0)
return __kernel_sindf(c1pio2 - x);
else
return __kernel_sindf(x + c1pio2);
}
}
if(ix<=0x40e231d5) { /* |x| ~<= 9*pi/4 */
if(ix>0x40afeddf) /* |x| ~> 7*pi/4 */
return __kernel_cosdf(x + (hx > 0 ? -c4pio2 : c4pio2));
else {
if(hx>0)
return __kernel_sindf(x - c3pio2);
else
return __kernel_sindf(-c3pio2 - x);
}
}
/* cos(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_cosdf(y);
case 1: return __kernel_sindf(-y);
case 2: return -__kernel_cosdf(y);
default:
return __kernel_sindf(y);
}
}
}
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