e_remainderf.c revision 97409 
1/* e_remainderf.c -- float version of e_remainder.c.
2 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
3 */
4
5/*
6 * ====================================================
7 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
8 *
9 * Developed at SunPro, a Sun Microsystems, Inc. business.
10 * Permission to use, copy, modify, and distribute this
11 * software is freely granted, provided that this notice
12 * is preserved.
13 * ====================================================
14 */
15
16#ifndef lint
17static char rcsid[] = "$FreeBSD: head/lib/msun/src/e_remainderf.c 97409 2002-05-28 17:51:46Z alfred $";
18#endif
19
20#include "math.h"
21#include "math_private.h"
22
23static const float zero = 0.0;
24
25
26	float __ieee754_remainderf(float x, float p)
27{
28	int32_t hx,hp;
29	u_int32_t sx;
30	float p_half;
31
32	GET_FLOAT_WORD(hx,x);
33	GET_FLOAT_WORD(hp,p);
34	sx = hx&0x80000000;
35	hp &= 0x7fffffff;
36	hx &= 0x7fffffff;
37
38    /* purge off exception values */
39	if(hp==0) return (x*p)/(x*p);	 	/* p = 0 */
40	if((hx>=0x7f800000)||			/* x not finite */
41	  ((hp>0x7f800000)))			/* p is NaN */
42	    return (x*p)/(x*p);
43
44
45	if (hp<=0x7effffff) x = __ieee754_fmodf(x,p+p);	/* now x < 2p */
46	if ((hx-hp)==0) return zero*x;
47	x  = fabsf(x);
48	p  = fabsf(p);
49	if (hp<0x01000000) {
50	    if(x+x>p) {
51		x-=p;
52		if(x+x>=p) x -= p;
53	    }
54	} else {
55	    p_half = (float)0.5*p;
56	    if(x>p_half) {
57		x-=p;
58		if(x>=p_half) x -= p;
59	    }
60	}
61	GET_FLOAT_WORD(hx,x);
62	SET_FLOAT_WORD(x,hx^sx);
63	return x;
64}
65