2 /* @(#)e_remainder.c 1.3 95/01/18 */
4 * ====================================================
5 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
7 * Developed at SunSoft, a Sun Microsystems, Inc. business.
8 * Permission to use, copy, modify, and distribute this
9 * software is freely granted, provided that this notice
11 * ====================================================
16 * returns x REM p = x - [x/p]*p as if in infinite
17 * precise arithmetic, where [x/p] is the (infinite bit)
18 * integer nearest x/p (in half way case choose the even one).
20 * Based on fmod() return x-[x/p]chopped*p exactlp.
24 #include "math_private.h"
26 static const double zero = 0.0;
30 remainder(double x, double p)
36 EXTRACT_WORDS(hx,lx,x);
37 EXTRACT_WORDS(hp,lp,p);
42 /* purge off exception values */
43 if((hp|lp)==0) return (x*p)/(x*p); /* p = 0 */
44 if((hx>=0x7ff00000)|| /* x not finite */
45 ((hp>=0x7ff00000)&& /* p is NaN */
46 (((hp-0x7ff00000)|lp)!=0)))
50 if (hp<=0x7fdfffff) x = fmod(x,p+p); /* now x < 2p */
51 if (((hx-hp)|(lx-lp))==0) return zero*x;
67 SET_HIGH_WORD(x,hx^sx);