diff options
Diffstat (limited to 'REORG.TODO/sysdeps/ieee754/ldbl-128ibm/e_remainderl.c')
| -rw-r--r-- | REORG.TODO/sysdeps/ieee754/ldbl-128ibm/e_remainderl.c | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/ieee754/ldbl-128ibm/e_remainderl.c b/REORG.TODO/sysdeps/ieee754/ldbl-128ibm/e_remainderl.c new file mode 100644 index 0000000000..68b8fb3519 --- /dev/null +++ b/REORG.TODO/sysdeps/ieee754/ldbl-128ibm/e_remainderl.c @@ -0,0 +1,81 @@ +/* e_fmodl.c -- long double version of e_fmod.c. + * Conversion to IEEE quad long double by Jakub Jelinek, jj@ultra.linux.cz. + */ +/* + * ==================================================== + * 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. + * ==================================================== + */ + +/* __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 fmodl() return x-[x/p]chopped*p exactlp. + */ + +#include <math.h> +#include <math_private.h> + +static const long double zero = 0.0L; + + +long double +__ieee754_remainderl(long double x, long double p) +{ + int64_t hx,hp; + u_int64_t sx,lx,lp; + long double p_half; + double xhi, xlo, phi, plo; + + ldbl_unpack (x, &xhi, &xlo); + EXTRACT_WORDS64 (hx, xhi); + EXTRACT_WORDS64 (lx, xlo); + ldbl_unpack (p, &phi, &plo); + EXTRACT_WORDS64 (hp, phi); + EXTRACT_WORDS64 (lp, plo); + sx = hx&0x8000000000000000ULL; + lp ^= hp & 0x8000000000000000ULL; + hp &= 0x7fffffffffffffffLL; + lx ^= sx; + hx &= 0x7fffffffffffffffLL; + if (lp == 0x8000000000000000ULL) + lp = 0; + if (lx == 0x8000000000000000ULL) + lx = 0; + + /* purge off exception values */ + if(hp==0) return (x*p)/(x*p); /* p = 0 */ + if((hx>=0x7ff0000000000000LL)|| /* x not finite */ + (hp>0x7ff0000000000000LL)) /* p is NaN */ + return (x*p)/(x*p); + + + if (hp<=0x7fdfffffffffffffLL) x = __ieee754_fmodl(x,p+p); /* now x < 2p */ + if (((hx-hp)|(lx-lp))==0) return zero*x; + x = fabsl(x); + p = fabsl(p); + if (hp<0x0020000000000000LL) { + if(x+x>p) { + x-=p; + if(x+x>=p) x -= p; + } + } else { + p_half = 0.5L*p; + if(x>p_half) { + x-=p; + if(x>=p_half) x -= p; + } + } + if (sx) + x = -x; + return x; +} +strong_alias (__ieee754_remainderl, __remainderl_finite) |