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