=================================================================== RCS file: /home/cvs/OpenXM_contrib/gmp/mpn/generic/Attic/rshift.c,v retrieving revision 1.1 retrieving revision 1.1.1.3 diff -u -p -r1.1 -r1.1.1.3 --- OpenXM_contrib/gmp/mpn/generic/Attic/rshift.c 2000/01/10 15:35:23 1.1 +++ OpenXM_contrib/gmp/mpn/generic/Attic/rshift.c 2003/08/25 16:06:20 1.1.1.3 @@ -1,20 +1,21 @@ -/* mpn_rshift -- Shift right a low-level natural-number integer. +/* mpn_rshift -- Shift right low level. -Copyright (C) 1991, 1993, 1994, 1996 Free Software Foundation, Inc. +Copyright 1991, 1993, 1994, 1996, 2000, 2001, 2002 Free Software Foundation, +Inc. This file is part of the GNU MP Library. The GNU MP Library is free software; you can redistribute it and/or modify -it under the terms of the GNU Library General Public License as published by -the Free Software Foundation; either version 2 of the License, or (at your +it under the terms of the GNU Lesser General Public License as published by +the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU MP Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public +or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. -You should have received a copy of the GNU Library General Public License +You should have received a copy of the GNU Lesser General Public License along with the GNU MP Library; see the file COPYING.LIB. If not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ @@ -22,67 +23,40 @@ MA 02111-1307, USA. */ #include "gmp.h" #include "gmp-impl.h" -/* Shift U (pointed to by UP and USIZE limbs long) CNT bits to the right - and store the USIZE least significant limbs of the result at WP. +/* Shift U (pointed to by up and N limbs long) cnt bits to the right + and store the n least significant limbs of the result at rp. The bits shifted out to the right are returned. Argument constraints: - 1. 0 < CNT < BITS_PER_MP_LIMB - 2. If the result is to be written over the input, WP must be <= UP. + 1. 0 < cnt < GMP_NUMB_BITS. + 2. If the result is to be written over the input, rp must be <= up. */ mp_limb_t -#if __STDC__ -mpn_rshift (register mp_ptr wp, - register mp_srcptr up, mp_size_t usize, - register unsigned int cnt) -#else -mpn_rshift (wp, up, usize, cnt) - register mp_ptr wp; - register mp_srcptr up; - mp_size_t usize; - register unsigned int cnt; -#endif +mpn_rshift (mp_ptr rp, mp_srcptr up, mp_size_t n, unsigned int cnt) { - register mp_limb_t high_limb, low_limb; - register unsigned sh_1, sh_2; - register mp_size_t i; + mp_limb_t high_limb, low_limb; + unsigned int tnc; + mp_size_t i; mp_limb_t retval; -#ifdef DEBUG - if (usize == 0 || cnt == 0) - abort (); -#endif + ASSERT (n >= 1); + ASSERT (cnt >= 1); + ASSERT (cnt < GMP_NUMB_BITS); + ASSERT (MPN_SAME_OR_INCR_P (rp, up, n)); - sh_1 = cnt; + tnc = GMP_NUMB_BITS - cnt; + high_limb = *up++; + retval = (high_limb << tnc) & GMP_NUMB_MASK; + low_limb = high_limb >> cnt; -#if 0 - if (sh_1 == 0) + for (i = n - 1; i != 0; i--) { - if (wp != up) - { - /* Copy from low end to high end, to allow specified input/output - overlapping. */ - for (i = 0; i < usize; i++) - wp[i] = up[i]; - } - return usize; + high_limb = *up++; + *rp++ = low_limb | ((high_limb << tnc) & GMP_NUMB_MASK); + low_limb = high_limb >> cnt; } -#endif - - wp -= 1; - sh_2 = BITS_PER_MP_LIMB - sh_1; - high_limb = up[0]; - retval = high_limb << sh_2; - low_limb = high_limb; - - for (i = 1; i < usize; i++) - { - high_limb = up[i]; - wp[i] = (low_limb >> sh_1) | (high_limb << sh_2); - low_limb = high_limb; - } - wp[i] = low_limb >> sh_1; + *rp = low_limb; return retval; }