diff options
Diffstat (limited to 'sysdeps/libm-ieee754/e_remainderl.c')
-rw-r--r-- | sysdeps/libm-ieee754/e_remainderl.c | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/sysdeps/libm-ieee754/e_remainderl.c b/sysdeps/libm-ieee754/e_remainderl.c new file mode 100644 index 0000000..3b2cd7c --- /dev/null +++ b/sysdeps/libm-ieee754/e_remainderl.c @@ -0,0 +1,83 @@ +/* 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; + + EXTRACT_LDOUBLE_WORDS(sex,x0,x1,x); + EXTRACT_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; +} |