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
17 static char rcsid[] = "$FreeBSD: src/lib/msun/src/e_remainderf.c,v 1.7 2002/05/28 18:15:04 alfred Exp $";
18 #endif
19
20 #include "math.h"
21 #include "math_private.h"
22
23 static const float zero = 0.0;
24
25
26 float
__ieee754_remainderf(float x,float p)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