e_remainderf.c revision 256281
153537Sbrian/* e_remainderf.c -- float version of e_remainder.c. 280728Sbrian * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. 353537Sbrian */ 453537Sbrian 553537Sbrian/* 653537Sbrian * ==================================================== 753537Sbrian * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 853537Sbrian * 953537Sbrian * Developed at SunPro, a Sun Microsystems, Inc. business. 1053537Sbrian * Permission to use, copy, modify, and distribute this 1153537Sbrian * software is freely granted, provided that this notice 1253537Sbrian * is preserved. 1353537Sbrian * ==================================================== 1453537Sbrian */ 1553537Sbrian 1653537Sbrian#include <sys/cdefs.h> 1753537Sbrian__FBSDID("$FreeBSD: stable/10/lib/msun/src/e_remainderf.c 176207 2008-02-12 17:11:36Z bde $"); 1853537Sbrian 1953537Sbrian#include "math.h" 2053537Sbrian#include "math_private.h" 2153537Sbrian 2253537Sbrianstatic const float zero = 0.0; 2353537Sbrian 2453537Sbrian 2553537Sbrianfloat 2653537Sbrian__ieee754_remainderf(float x, float p) 2753537Sbrian{ 2853537Sbrian int32_t hx,hp; 2953537Sbrian u_int32_t sx; 3053537Sbrian float p_half; 3153537Sbrian 3253537Sbrian GET_FLOAT_WORD(hx,x); 3353537Sbrian GET_FLOAT_WORD(hp,p); 3453537Sbrian sx = hx&0x80000000; 3553537Sbrian hp &= 0x7fffffff; 3653537Sbrian hx &= 0x7fffffff; 3753537Sbrian 3853537Sbrian /* purge off exception values */ 3953537Sbrian if(hp==0) return (x*p)/(x*p); /* p = 0 */ 4053537Sbrian if((hx>=0x7f800000)|| /* x not finite */ 4153537Sbrian ((hp>0x7f800000))) /* p is NaN */ 4253537Sbrian return ((long double)x*p)/((long double)x*p); 4353537Sbrian 4453537Sbrian 4553537Sbrian if (hp<=0x7effffff) x = __ieee754_fmodf(x,p+p); /* now x < 2p */ 4653537Sbrian if ((hx-hp)==0) return zero*x; 4753537Sbrian x = fabsf(x); 4866602Sbrian p = fabsf(p); 4953537Sbrian if (hp<0x01000000) { 5053537Sbrian if(x+x>p) { 5153537Sbrian x-=p; 5253537Sbrian if(x+x>=p) x -= p; 5353537Sbrian } 5453537Sbrian } else { 5553537Sbrian p_half = (float)0.5*p; 5653537Sbrian if(x>p_half) { 5753537Sbrian x-=p; 5853537Sbrian if(x>=p_half) x -= p; 5953537Sbrian } 6053537Sbrian } 6153537Sbrian GET_FLOAT_WORD(hx,x); 6253537Sbrian if ((hx&0x7fffffff)==0) hx = 0; 6353537Sbrian SET_FLOAT_WORD(x,hx^sx); 6486705Sbrian return x; 6586705Sbrian} 6653537Sbrian