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/* origin: FreeBSD /usr/src/lib/msun/src/e_remainderf.c */
/*
* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
*/
/*
* ====================================================
* 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 "libm.h"
static const float zero = 0.0;
float remainderf(float x, float p)
{
int32_t hx,hp;
uint32_t sx;
float p_half;
GET_FLOAT_WORD(hx, x);
GET_FLOAT_WORD(hp, p);
sx = hx & 0x80000000;
hp &= 0x7fffffff;
hx &= 0x7fffffff;
/* purge off exception values */
if (hp == 0) /* p = 0 */
return (x*p)/(x*p);
if (hx >= 0x7f800000 || hp > 0x7f800000) /* x not finite, p is NaN */
// FIXME: why long double?
return ((long double)x*p)/((long double)x*p);
if (hp <= 0x7effffff)
x = fmodf(x, p + p); /* now x < 2p */
if (hx - hp == 0)
return zero*x;
x = fabsf(x);
p = fabsf(p);
if (hp < 0x01000000) {
if (x + x > p) {
x -= p;
if (x + x >= p)
x -= p;
}
} else {
p_half = 0.5f*p;
if (x > p_half) {
x -= p;
if (x >= p_half)
x -= p;
}
}
GET_FLOAT_WORD(hx, x);
if ((hx & 0x7fffffff) == 0)
hx = 0;
SET_FLOAT_WORD(x, hx ^ sx);
return x;
}
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