diff options
author | Torbjorn Granlund <tg@gmplib.org> | 2019-12-23 21:26:40 +0100 |
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committer | Torbjorn Granlund <tg@gmplib.org> | 2019-12-23 21:26:40 +0100 |
commit | afd0b9db45561b8cbfca78a20a98e182db2554b4 (patch) | |
tree | c51766f47b90956b1f4f326a847ad4c1da6ec18b /mpf | |
parent | c967393f31b0f912043dd89261e655a470b1ce31 (diff) | |
download | gmp-afd0b9db45561b8cbfca78a20a98e182db2554b4.tar.gz |
Rewrite to invoke mpn_sqr when appropriate.
Diffstat (limited to 'mpf')
-rw-r--r-- | mpf/mul.c | 134 |
1 files changed, 86 insertions, 48 deletions
@@ -1,6 +1,6 @@ /* mpf_mul -- Multiply two floats. -Copyright 1993, 1994, 1996, 2001, 2005 Free Software Foundation, Inc. +Copyright 1993, 1994, 1996, 2001, 2005, 2019 Free Software Foundation, Inc. This file is part of the GNU MP Library. @@ -33,64 +33,102 @@ see https://www.gnu.org/licenses/. */ 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; + mp_size_t rsize; + mp_limb_t cy_limb; + mp_ptr rp, tp; + mp_size_t adj; + TMP_DECL; - usize = u->_mp_size; - vsize = v->_mp_size; - sign_product = usize ^ vsize; + if (u == v) + { + mp_srcptr up; + mp_size_t usize; - usize = ABS (usize); - vsize = ABS (vsize); + usize = u->_mp_size; + sign_product = usize; - up = u->_mp_d; - vp = v->_mp_d; - if (usize > prec) - { - up += usize - prec; - usize = prec; - } - if (vsize > prec) - { - vp += vsize - prec; - vsize = prec; - } + usize = ABS (usize); - if (usize == 0 || vsize == 0) - { - r->_mp_size = 0; - r->_mp_exp = 0; /* ??? */ + up = u->_mp_d; + if (usize > prec) + { + up += usize - prec; + usize = prec; + } + + if (usize == 0) + { + r->_mp_size = 0; + r->_mp_exp = 0; /* ??? */ + return; + } + else + { + TMP_MARK; + rsize = 2 * usize; + tp = TMP_ALLOC_LIMBS (rsize); + + mpn_sqr (tp, up, usize); + cy_limb = tp[rsize - 1]; + } } else { - mp_size_t rsize; - mp_limb_t cy_limb; - mp_ptr rp, tp; - mp_size_t adj; - TMP_DECL; - - TMP_MARK; - 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) + mp_srcptr up, vp; + mp_size_t usize, vsize; + + 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) { - tp += rsize - prec; - rsize = prec; + r->_mp_size = 0; + r->_mp_exp = 0; + return; } - 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; + else + { + TMP_MARK; + 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)); - TMP_FREE; + } } + + 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; } |