mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-05 11:11:04 +00:00
84 lines
1.9 KiB
C
84 lines
1.9 KiB
C
/* e_remainderl.c -- long double version of e_remainder.c.
|
|
* Conversion to long double by Ulrich Drepper,
|
|
* Cygnus Support, drepper@cygnus.com.
|
|
*/
|
|
|
|
/*
|
|
* ====================================================
|
|
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
|
|
*
|
|
* Developed at SunPro, a Sun Microsystems, Inc. business.
|
|
* Permission to use, copy, modify, and distribute this
|
|
* software is freely granted, provided that this notice
|
|
* is preserved.
|
|
* ====================================================
|
|
*/
|
|
|
|
#if defined(LIBM_SCCS) && !defined(lint)
|
|
static char rcsid[] = "$NetBSD: $";
|
|
#endif
|
|
|
|
/* __ieee754_remainderl(x,p)
|
|
* Return :
|
|
* returns x REM p = x - [x/p]*p as if in infinite
|
|
* precise arithmetic, where [x/p] is the (infinite bit)
|
|
* integer nearest x/p (in half way case choose the even one).
|
|
* Method :
|
|
* Based on fmod() return x-[x/p]chopped*p exactlp.
|
|
*/
|
|
|
|
#include "math.h"
|
|
#include "math_private.h"
|
|
|
|
#ifdef __STDC__
|
|
static const long double zero = 0.0;
|
|
#else
|
|
static long double zero = 0.0;
|
|
#endif
|
|
|
|
|
|
#ifdef __STDC__
|
|
long double __ieee754_remainderl(long double x, long double p)
|
|
#else
|
|
long double __ieee754_remainderl(x,p)
|
|
long double x,p;
|
|
#endif
|
|
{
|
|
u_int32_t sx,sex,sep,x0,x1,p0,p1;
|
|
long double p_half;
|
|
|
|
GET_LDOUBLE_WORDS(sex,x0,x1,x);
|
|
GET_LDOUBLE_WORDS(sep,p0,p1,p);
|
|
sx = sex&0x8000;
|
|
sep &= 0x7fff;
|
|
sex &= 0x7fff;
|
|
|
|
/* purge off exception values */
|
|
if((sep|p0|p1)==0) return (x*p)/(x*p); /* p = 0 */
|
|
if((sex==0x7fff)|| /* x not finite */
|
|
((sep==0x7fff)&& /* p is NaN */
|
|
((p0|p1)!=0)))
|
|
return (x*p)/(x*p);
|
|
|
|
|
|
if (sep<0x7ffe) x = __ieee754_fmodl(x,p+p); /* now x < 2p */
|
|
if (((sex-sep)|(x0-p0)|(x1-p1))==0) return zero*x;
|
|
x = fabsl(x);
|
|
p = fabsl(p);
|
|
if (sep<0x0002) {
|
|
if(x+x>p) {
|
|
x-=p;
|
|
if(x+x>=p) x -= p;
|
|
}
|
|
} else {
|
|
p_half = 0.5*p;
|
|
if(x>p_half) {
|
|
x-=p;
|
|
if(x>=p_half) x -= p;
|
|
}
|
|
}
|
|
GET_LDOUBLE_EXP(sex,x);
|
|
SET_LDOUBLE_EXP(x,sex^sx);
|
|
return x;
|
|
}
|