/* 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>

#include "math.h"
#define INLINE_KERNEL_COSDF
#define INLINE_KERNEL_SINDF
#define INLINE_REM_PIO2F
#include "math_private.h"
#include "e_rem_pio2f.c"
#include "k_cosf.c"
#include "k_sinf.c"

/* 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);
        }
    }
}