e_remainderf.c revision 97413 
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 97413 2002-05-28 18:15:04Z alfred $";
18#endif
19
20#include "math.h"
21#include "math_private.h"
22
23static const float zero = 0.0;
24
25
26float
27__ieee754_remainderf(float x, float p)
28{
29	int32_t hx,hp;
30	u_int32_t sx;
31	float p_half;
32
33	GET_FLOAT_WORD(hx,x);
34	GET_FLOAT_WORD(hp,p);
35	sx = hx&0x80000000;
36	hp &= 0x7fffffff;
37	hx &= 0x7fffffff;
38
39    /* purge off exception values */
40	if(hp==0) return (x*p)/(x*p);	 	/* p = 0 */
41	if((hx>=0x7f800000)||			/* x not finite */
42	  ((hp>0x7f800000)))			/* p is NaN */
43	    return (x*p)/(x*p);
44
45
46	if (hp<=0x7effffff) x = __ieee754_fmodf(x,p+p);	/* now x < 2p */
47	if ((hx-hp)==0) return zero*x;
48	x  = fabsf(x);
49	p  = fabsf(p);
50	if (hp<0x01000000) {
51	    if(x+x>p) {
52		x-=p;
53		if(x+x>=p) x -= p;
54	    }
55	} else {
56	    p_half = (float)0.5*p;
57	    if(x>p_half) {
58		x-=p;
59		if(x>=p_half) x -= p;
60	    }
61	}
62	GET_FLOAT_WORD(hx,x);
63	SET_FLOAT_WORD(x,hx^sx);
64	return x;
65}
66