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author | Kevin Ryde <user42@zip.com.au> | 2001-10-02 01:08:46 +0200 |
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committer | Kevin Ryde <user42@zip.com.au> | 2001-10-02 01:08:46 +0200 |
commit | 07cf896c2f829c1dd6a5456aa7e710044a6e594a (patch) | |
tree | 51a4079cd2a37c6d276e444f50cddd9aaf2c6540 /mpz/aors_ui.h | |
parent | 9edc48e967f743b5438c9c47a481ded5f8c50069 (diff) | |
download | gmp-07cf896c2f829c1dd6a5456aa7e710044a6e594a.tar.gz |
* mpz/aors_ui.h: Renamed from mpz/aors_ui.c.
Diffstat (limited to 'mpz/aors_ui.h')
-rw-r--r-- | mpz/aors_ui.h | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/mpz/aors_ui.h b/mpz/aors_ui.h new file mode 100644 index 000000000..c4ed1bd00 --- /dev/null +++ b/mpz/aors_ui.h @@ -0,0 +1,99 @@ +/* mpz_add_ui, mpz_sub_ui -- Add or subtract an mpz_t and an unsigned + one-word integer. + +Copyright 1991, 1993, 1994, 1996, 1999, 2000, 2001 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" + + +#ifdef OPERATION_add_ui +#define FUNCTION mpz_add_ui +#define VARIATION_CMP >= +#define VARIATION_NEG +#define VARIATION_UNNEG - +#endif + +#ifdef OPERATION_sub_ui +#define FUNCTION mpz_sub_ui +#define VARIATION_CMP < +#define VARIATION_NEG - +#define VARIATION_UNNEG +#endif + +#ifndef FUNCTION +Error, need OPERATION_add_ui or OPERATION_sub_ui +#endif + + +void +FUNCTION (mpz_ptr w, mpz_srcptr u, unsigned long int v) +{ + mp_srcptr up; + mp_ptr wp; + mp_size_t usize, wsize; + mp_size_t abs_usize; + + usize = u->_mp_size; + abs_usize = ABS (usize); + + /* If not space for W (and possible carry), increase space. */ + wsize = abs_usize + 1; + if (w->_mp_alloc < wsize) + _mpz_realloc (w, wsize); + + /* These must be after realloc (U may be the same as W). */ + up = u->_mp_d; + wp = w->_mp_d; + + if (abs_usize == 0) + { + wp[0] = v; + w->_mp_size = VARIATION_NEG (v != 0); + return; + } + + if (usize VARIATION_CMP 0) + { + mp_limb_t cy; + cy = mpn_add_1 (wp, up, abs_usize, (mp_limb_t) v); + wp[abs_usize] = cy; + wsize = VARIATION_NEG (abs_usize + cy); + } + else + { + /* The signs are different. Need exact comparison to determine + which operand to subtract from which. */ + if (abs_usize == 1 && up[0] < v) + { + wp[0] = v - up[0]; + wsize = VARIATION_NEG 1; + } + else + { + mpn_sub_1 (wp, up, abs_usize, (mp_limb_t) v); + /* Size can decrease with at most one limb. */ + wsize = VARIATION_UNNEG (abs_usize - (wp[abs_usize - 1] == 0)); + } + } + + w->_mp_size = wsize; +} |