e_remainderf.c (1479B)
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 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 }