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