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Diffstat (limited to 'gmp/mpf/mul.c')
-rw-r--r-- | gmp/mpf/mul.c | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/gmp/mpf/mul.c b/gmp/mpf/mul.c new file mode 100644 index 0000000000..41d1db7c14 --- /dev/null +++ b/gmp/mpf/mul.c @@ -0,0 +1,96 @@ +/* mpf_mul -- Multiply two floats. + +Copyright 1993, 1994, 1996, 2001, 2005 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 "gmp.h" +#include "gmp-impl.h" + +void +mpf_mul (mpf_ptr r, mpf_srcptr u, mpf_srcptr v) +{ + mp_srcptr up, vp; + mp_size_t usize, vsize; + mp_size_t sign_product; + mp_size_t prec = r->_mp_prec; + TMP_DECL; + + TMP_MARK; + usize = u->_mp_size; + vsize = v->_mp_size; + sign_product = usize ^ vsize; + + usize = ABS (usize); + vsize = ABS (vsize); + + up = u->_mp_d; + vp = v->_mp_d; + if (usize > prec) + { + up += usize - prec; + usize = prec; + } + if (vsize > prec) + { + vp += vsize - prec; + vsize = prec; + } + + if (usize == 0 || vsize == 0) + { + r->_mp_size = 0; + r->_mp_exp = 0; /* ??? */ + } + else + { + mp_size_t rsize; + mp_limb_t cy_limb; + mp_ptr rp, tp; + mp_size_t adj; + + rsize = usize + vsize; + tp = TMP_ALLOC_LIMBS (rsize); + cy_limb = (usize >= vsize + ? mpn_mul (tp, up, usize, vp, vsize) + : mpn_mul (tp, vp, vsize, up, usize)); + + adj = cy_limb == 0; + rsize -= adj; + prec++; + if (rsize > prec) + { + tp += rsize - prec; + rsize = prec; + } + rp = r->_mp_d; + MPN_COPY (rp, tp, rsize); + r->_mp_exp = u->_mp_exp + v->_mp_exp - adj; + r->_mp_size = sign_product >= 0 ? rsize : -rsize; + } + TMP_FREE; +} |