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-rw-r--r--contrib/libgmp/mpz/mul.c127
1 files changed, 127 insertions, 0 deletions
diff --git a/contrib/libgmp/mpz/mul.c b/contrib/libgmp/mpz/mul.c
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+++ b/contrib/libgmp/mpz/mul.c
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+/* mpz_mul -- Multiply two integers.
+
+Copyright (C) 1991, 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 Library General Public License as published by
+the Free Software Foundation; either version 2 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
+License for more details.
+
+You should have received a copy of the GNU Library 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"
+
+#ifndef BERKELEY_MP
+void
+#if __STDC__
+mpz_mul (mpz_ptr w, mpz_srcptr u, mpz_srcptr v)
+#else
+mpz_mul (w, u, v)
+ mpz_ptr w;
+ mpz_srcptr u;
+ mpz_srcptr v;
+#endif
+#else /* BERKELEY_MP */
+void
+#if __STDC__
+mult (mpz_srcptr u, mpz_srcptr v, mpz_ptr w)
+#else
+mult (u, v, w)
+ mpz_srcptr u;
+ mpz_srcptr v;
+ mpz_ptr w;
+#endif
+#endif /* BERKELEY_MP */
+{
+ mp_size_t usize = u->_mp_size;
+ mp_size_t vsize = v->_mp_size;
+ mp_size_t wsize;
+ mp_size_t sign_product;
+ mp_ptr up, vp;
+ mp_ptr wp;
+ mp_ptr free_me = NULL;
+ size_t free_me_size;
+ mp_limb_t cy_limb;
+ TMP_DECL (marker);
+
+ TMP_MARK (marker);
+ sign_product = usize ^ vsize;
+ usize = ABS (usize);
+ vsize = ABS (vsize);
+
+ if (usize < vsize)
+ {
+ /* Swap U and V. */
+ {const __mpz_struct *t = u; u = v; v = t;}
+ {mp_size_t t = usize; usize = vsize; vsize = t;}
+ }
+
+ up = u->_mp_d;
+ vp = v->_mp_d;
+ wp = w->_mp_d;
+
+ /* Ensure W has space enough to store the result. */
+ wsize = usize + vsize;
+ if (w->_mp_alloc < wsize)
+ {
+ if (wp == up || wp == vp)
+ {
+ free_me = wp;
+ free_me_size = w->_mp_alloc;
+ }
+ else
+ (*_mp_free_func) (wp, w->_mp_alloc * BYTES_PER_MP_LIMB);
+
+ w->_mp_alloc = wsize;
+ wp = (mp_ptr) (*_mp_allocate_func) (wsize * BYTES_PER_MP_LIMB);
+ w->_mp_d = wp;
+ }
+ else
+ {
+ /* Make U and V not overlap with W. */
+ if (wp == up)
+ {
+ /* W and U are identical. Allocate temporary space for U. */
+ up = (mp_ptr) TMP_ALLOC (usize * BYTES_PER_MP_LIMB);
+ /* 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 = (mp_ptr) TMP_ALLOC (vsize * BYTES_PER_MP_LIMB);
+ /* Copy to the temporary space. */
+ MPN_COPY (vp, wp, vsize);
+ }
+ }
+
+ if (vsize == 0)
+ {
+ wsize = 0;
+ }
+ else
+ {
+ cy_limb = mpn_mul (wp, up, usize, vp, vsize);
+ wsize = usize + vsize;
+ wsize -= cy_limb == 0;
+ }
+
+ w->_mp_size = sign_product < 0 ? -wsize : wsize;
+ if (free_me != NULL)
+ (*_mp_free_func) (free_me, free_me_size * BYTES_PER_MP_LIMB);
+ TMP_FREE (marker);
+}
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