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author | Ulrich Drepper <drepper@redhat.com> | 2005-12-14 15:06:39 +0000 |
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committer | Ulrich Drepper <drepper@redhat.com> | 2005-12-14 15:06:39 +0000 |
commit | 9d13fb2413921c713f83efe331e8e4d219c62c6b (patch) | |
tree | 2d44d7ac45ab2d147eb8361bbff880c365aa8ad5 /stdlib/sub_n.c | |
parent | 2005-12-13 Ulrich Drepper <drepper@redhat.com> (diff) | |
download | glibc-9d13fb2413921c713f83efe331e8e4d219c62c6b.tar.gz glibc-9d13fb2413921c713f83efe331e8e4d219c62c6b.tar.bz2 glibc-9d13fb2413921c713f83efe331e8e4d219c62c6b.zip |
Moved to csu/errno-loc.c.
Diffstat (limited to 'stdlib/sub_n.c')
-rw-r--r-- | stdlib/sub_n.c | 62 |
1 files changed, 62 insertions, 0 deletions
diff --git a/stdlib/sub_n.c b/stdlib/sub_n.c new file mode 100644 index 0000000000..987ad91eb1 --- /dev/null +++ b/stdlib/sub_n.c @@ -0,0 +1,62 @@ +/* mpn_sub_n -- Subtract two limb vectors of equal, non-zero length. + +Copyright (C) 1992, 1993, 1994, 1996 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 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 Lesser General Public +License for more details. + +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. */ + +#include <gmp.h> +#include "gmp-impl.h" + +mp_limb_t +#if __STDC__ +mpn_sub_n (mp_ptr res_ptr, mp_srcptr s1_ptr, mp_srcptr s2_ptr, mp_size_t size) +#else +mpn_sub_n (res_ptr, s1_ptr, s2_ptr, size) + register mp_ptr res_ptr; + register mp_srcptr s1_ptr; + register mp_srcptr s2_ptr; + mp_size_t size; +#endif +{ + register mp_limb_t x, y, cy; + register mp_size_t j; + + /* The loop counter and index J goes from -SIZE to -1. This way + the loop becomes faster. */ + j = -size; + + /* Offset the base pointers to compensate for the negative indices. */ + s1_ptr -= j; + s2_ptr -= j; + res_ptr -= j; + + cy = 0; + do + { + y = s2_ptr[j]; + x = s1_ptr[j]; + y += cy; /* add previous carry to subtrahend */ + cy = (y < cy); /* get out carry from that addition */ + y = x - y; /* main subtract */ + cy = (y > x) + cy; /* get out carry from the subtract, combine */ + res_ptr[j] = y; + } + while (++j != 0); + + return cy; +} |