This work is based in part on code from NetBSD libm, libc and kernel. The library is partly public domain and partly BSD-style licensed.
67 lines
1.5 KiB
C
67 lines
1.5 KiB
C
/* e_remainderf.c -- float version of e_remainder.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 <sys/cdefs.h>
|
|
#if defined(LIBM_SCCS) && !defined(lint)
|
|
__RCSID("$NetBSD: e_remainderf.c,v 1.7 2002/05/26 22:01:52 wiz Exp $");
|
|
#endif
|
|
|
|
#include "math.h"
|
|
#include "math_private.h"
|
|
|
|
static const float zero = 0.0;
|
|
|
|
|
|
float
|
|
__ieee754_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) return (x*p)/(x*p); /* p = 0 */
|
|
if((hx>=0x7f800000)|| /* x not finite */
|
|
((hp>0x7f800000))) /* p is NaN */
|
|
return (x*p)/(x*p);
|
|
|
|
|
|
if (hp<=0x7effffff) x = __ieee754_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 = (float)0.5*p;
|
|
if(x>p_half) {
|
|
x-=p;
|
|
if(x>=p_half) x -= p;
|
|
}
|
|
}
|
|
GET_FLOAT_WORD(hx,x);
|
|
SET_FLOAT_WORD(x,hx^sx);
|
|
return x;
|
|
}
|