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 <sys/cdefs.h> 17 #if defined(LIBM_SCCS) && !defined(lint) 18 __RCSID("$NetBSD: e_remainderf.c,v 1.6 1999/07/02 15:37:41 simonb Exp $"); 19 #endif 20 21 #include "math.h" 22 #include "math_private.h" 23 24 #ifdef __STDC__ 25 static const float zero = 0.0; 26 #else 27 static float zero = 0.0; 28 #endif 29 30 31 #ifdef __STDC__ 32 float __ieee754_remainderf(float x, float p) 33 #else 34 float __ieee754_remainderf(x,p) 35 float x,p; 36 #endif 37 { 38 int32_t hx,hp; 39 u_int32_t sx; 40 float p_half; 41 42 GET_FLOAT_WORD(hx,x); 43 GET_FLOAT_WORD(hp,p); 44 sx = hx&0x80000000; 45 hp &= 0x7fffffff; 46 hx &= 0x7fffffff; 47 48 /* purge off exception values */ 49 if(hp==0) return (x*p)/(x*p); /* p = 0 */ 50 if((hx>=0x7f800000)|| /* x not finite */ 51 ((hp>0x7f800000))) /* p is NaN */ 52 return (x*p)/(x*p); 53 54 55 if (hp<=0x7effffff) x = __ieee754_fmodf(x,p+p); /* now x < 2p */ 56 if ((hx-hp)==0) return zero*x; 57 x = fabsf(x); 58 p = fabsf(p); 59 if (hp<0x01000000) { 60 if(x+x>p) { 61 x-=p; 62 if(x+x>=p) x -= p; 63 } 64 } else { 65 p_half = (float)0.5*p; 66 if(x>p_half) { 67 x-=p; 68 if(x>=p_half) x -= p; 69 } 70 } 71 GET_FLOAT_WORD(hx,x); 72 SET_FLOAT_WORD(x,hx^sx); 73 return x; 74 } 75