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author | Javier Jardón <jjardon@gnome.org> | 2015-04-27 11:43:02 +0100 |
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committer | Pedro Alvarez <pedro.alvarez@codethink.co.uk> | 2016-05-27 16:24:35 +0100 |
commit | 3c6e2acb7a85497467c87410220ec34e275b44ed (patch) | |
tree | 9071b814720e96d21a3fed8221b2284d8b3debf3 /gmp/mpz/mul.c | |
parent | 7b48bf2011b4020c4a5a2d5d4149b03983f72cc2 (diff) | |
download | gcc-tarball-3c6e2acb7a85497467c87410220ec34e275b44ed.tar.gz |
Add GMP 6.0.0a tarball
Diffstat (limited to 'gmp/mpz/mul.c')
-rw-r--r-- | gmp/mpz/mul.c | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/gmp/mpz/mul.c b/gmp/mpz/mul.c new file mode 100644 index 0000000000..59a279eca6 --- /dev/null +++ b/gmp/mpz/mul.c @@ -0,0 +1,157 @@ +/* mpz_mul -- Multiply two integers. + +Copyright 1991, 1993, 1994, 1996, 2000, 2001, 2005, 2009, 2011, 2012 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 either: + + * the GNU Lesser General Public License as published by the Free + Software Foundation; either version 3 of the License, or (at your + option) any later version. + +or + + * the GNU General Public License as published by the Free Software + Foundation; either version 2 of the License, or (at your option) any + later version. + +or both in parallel, as here. + +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 General Public License +for more details. + +You should have received copies of the GNU General Public License and the +GNU Lesser General Public License along with the GNU MP Library. If not, +see https://www.gnu.org/licenses/. */ + +#include <stdio.h> /* for NULL */ +#include "gmp.h" +#include "gmp-impl.h" + + +void +mpz_mul (mpz_ptr w, mpz_srcptr u, mpz_srcptr v) +{ + mp_size_t usize; + mp_size_t vsize; + mp_size_t wsize; + mp_size_t sign_product; + mp_ptr up, vp; + mp_ptr wp; + mp_ptr free_me; + size_t free_me_size; + mp_limb_t cy_limb; + TMP_DECL; + + usize = SIZ (u); + vsize = SIZ (v); + sign_product = usize ^ vsize; + usize = ABS (usize); + vsize = ABS (vsize); + + if (usize < vsize) + { + MPZ_SRCPTR_SWAP (u, v); + MP_SIZE_T_SWAP (usize, vsize); + } + + if (vsize == 0) + { + SIZ (w) = 0; + return; + } + +#if HAVE_NATIVE_mpn_mul_2 + if (vsize <= 2) + { + wp = MPZ_REALLOC (w, usize+vsize); + if (vsize == 1) + cy_limb = mpn_mul_1 (wp, PTR (u), usize, PTR (v)[0]); + else + { + cy_limb = mpn_mul_2 (wp, PTR (u), usize, PTR (v)); + usize++; + } + wp[usize] = cy_limb; + usize += (cy_limb != 0); + SIZ (w) = (sign_product >= 0 ? usize : -usize); + return; + } +#else + if (vsize == 1) + { + wp = MPZ_REALLOC (w, usize+1); + cy_limb = mpn_mul_1 (wp, PTR (u), usize, PTR (v)[0]); + wp[usize] = cy_limb; + usize += (cy_limb != 0); + SIZ (w) = (sign_product >= 0 ? usize : -usize); + return; + } +#endif + + TMP_MARK; + free_me = NULL; + up = PTR (u); + vp = PTR (v); + wp = PTR (w); + + /* Ensure W has space enough to store the result. */ + wsize = usize + vsize; + if (ALLOC (w) < wsize) + { + if (wp == up || wp == vp) + { + free_me = wp; + free_me_size = ALLOC (w); + } + else + (*__gmp_free_func) (wp, (size_t) ALLOC (w) * GMP_LIMB_BYTES); + + ALLOC (w) = wsize; + wp = (mp_ptr) (*__gmp_allocate_func) ((size_t) wsize * GMP_LIMB_BYTES); + PTR (w) = wp; + } + else + { + /* Make U and V not overlap with W. */ + if (wp == up) + { + /* W and U are identical. Allocate temporary space for U. */ + up = TMP_ALLOC_LIMBS (usize); + /* Is V identical too? Keep it identical with U. */ + if (wp == vp) + vp = up; + /* Copy to the temporary space. */ + MPN_COPY (up, wp, usize); + } + else if (wp == vp) + { + /* W and V are identical. Allocate temporary space for V. */ + vp = TMP_ALLOC_LIMBS (vsize); + /* Copy to the temporary space. */ + MPN_COPY (vp, wp, vsize); + } + } + + if (up == vp) + { + mpn_sqr (wp, up, usize); + cy_limb = wp[wsize - 1]; + } + else + { + cy_limb = mpn_mul (wp, up, usize, vp, vsize); + } + + wsize -= cy_limb == 0; + + SIZ (w) = sign_product < 0 ? -wsize : wsize; + if (free_me != NULL) + (*__gmp_free_func) (free_me, free_me_size * GMP_LIMB_BYTES); + TMP_FREE; +} |