1*05a0b428SJohn Marino /* e_remainderf.c -- float version of e_remainder.c.
2*05a0b428SJohn Marino * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
3*05a0b428SJohn Marino */
4*05a0b428SJohn Marino
5*05a0b428SJohn Marino /*
6*05a0b428SJohn Marino * ====================================================
7*05a0b428SJohn Marino * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
8*05a0b428SJohn Marino *
9*05a0b428SJohn Marino * Developed at SunPro, a Sun Microsystems, Inc. business.
10*05a0b428SJohn Marino * Permission to use, copy, modify, and distribute this
11*05a0b428SJohn Marino * software is freely granted, provided that this notice
12*05a0b428SJohn Marino * is preserved.
13*05a0b428SJohn Marino * ====================================================
14*05a0b428SJohn Marino */
15*05a0b428SJohn Marino
16*05a0b428SJohn Marino #include "math.h"
17*05a0b428SJohn Marino #include "math_private.h"
18*05a0b428SJohn Marino
19*05a0b428SJohn Marino static const float zero = 0.0;
20*05a0b428SJohn Marino
21*05a0b428SJohn Marino float
remainderf(float x,float p)22*05a0b428SJohn Marino remainderf(float x, float p)
23*05a0b428SJohn Marino {
24*05a0b428SJohn Marino int32_t hx,hp;
25*05a0b428SJohn Marino u_int32_t sx;
26*05a0b428SJohn Marino float p_half;
27*05a0b428SJohn Marino
28*05a0b428SJohn Marino GET_FLOAT_WORD(hx,x);
29*05a0b428SJohn Marino GET_FLOAT_WORD(hp,p);
30*05a0b428SJohn Marino sx = hx&0x80000000;
31*05a0b428SJohn Marino hp &= 0x7fffffff;
32*05a0b428SJohn Marino hx &= 0x7fffffff;
33*05a0b428SJohn Marino
34*05a0b428SJohn Marino /* purge off exception values */
35*05a0b428SJohn Marino if(hp==0) return (x*p)/(x*p); /* p = 0 */
36*05a0b428SJohn Marino if((hx>=0x7f800000)|| /* x not finite */
37*05a0b428SJohn Marino ((hp>0x7f800000))) /* p is NaN */
38*05a0b428SJohn Marino return (x*p)/(x*p);
39*05a0b428SJohn Marino
40*05a0b428SJohn Marino
41*05a0b428SJohn Marino if (hp<=0x7effffff) x = fmodf(x,p+p); /* now x < 2p */
42*05a0b428SJohn Marino if ((hx-hp)==0) return zero*x;
43*05a0b428SJohn Marino x = fabsf(x);
44*05a0b428SJohn Marino p = fabsf(p);
45*05a0b428SJohn Marino if (hp<0x01000000) {
46*05a0b428SJohn Marino if(x+x>p) {
47*05a0b428SJohn Marino x-=p;
48*05a0b428SJohn Marino if(x+x>=p) x -= p;
49*05a0b428SJohn Marino }
50*05a0b428SJohn Marino } else {
51*05a0b428SJohn Marino p_half = (float)0.5*p;
52*05a0b428SJohn Marino if(x>p_half) {
53*05a0b428SJohn Marino x-=p;
54*05a0b428SJohn Marino if(x>=p_half) x -= p;
55*05a0b428SJohn Marino }
56*05a0b428SJohn Marino }
57*05a0b428SJohn Marino GET_FLOAT_WORD(hx,x);
58*05a0b428SJohn Marino SET_FLOAT_WORD(x,hx^sx);
59*05a0b428SJohn Marino return x;
60*05a0b428SJohn Marino }
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