1 /* mpf_div -- Divide two floats.
3 Copyright (C) 1993, 1994, 1996 Free Software Foundation, Inc.
5 This file is part of the GNU MP Library.
7 The GNU MP Library is free software; you can redistribute it and/or modify
8 it under the terms of the GNU Library General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or (at your
10 option) any later version.
12 The GNU MP Library is distributed in the hope that it will be useful, but
13 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
14 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public
15 License for more details.
17 You should have received a copy of the GNU Library General Public License
18 along with the GNU MP Library; see the file COPYING.LIB. If not, write to
19 the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
20 MA 02111-1307, USA. */
28 mpf_div (mpf_ptr r, mpf_srcptr u, mpf_srcptr v)
38 mp_size_t usize, vsize;
39 mp_size_t rsize, tsize;
40 mp_size_t sign_quotient;
42 unsigned normalization_steps;
49 sign_quotient = usize ^ vsize;
55 vsize = 1 / vsize; /* divide by zero as directed */
64 rexp = u->_mp_exp - v->_mp_exp;
77 tp = (mp_ptr) TMP_ALLOC ((tsize + 1) * BYTES_PER_MP_LIMB);
87 MPN_ZERO (tp, tsize - usize);
88 rtp = tp + (tsize - usize);
91 count_leading_zeros (normalization_steps, vp[vsize - 1]);
93 /* Normalize the divisor and the dividend. */
94 if (normalization_steps != 0)
99 /* Shift up the divisor setting the most significant bit of
100 the most significant limb. Use temporary storage not to clobber
101 the original contents of the divisor. */
102 tmp = (mp_ptr) TMP_ALLOC (vsize * BYTES_PER_MP_LIMB);
103 mpn_lshift (tmp, vp, vsize, normalization_steps);
106 /* Shift up the dividend, possibly introducing a new most
107 significant word. Move the shifted dividend in the remainder
109 nlimb = mpn_lshift (rtp, up, usize, normalization_steps);
119 /* The divisor is already normalized, as required.
120 Copy it to temporary space if it overlaps with the quotient. */
121 if (vp - rp <= tsize - vsize)
123 mp_ptr tmp = (mp_ptr) TMP_ALLOC (vsize * BYTES_PER_MP_LIMB);
124 MPN_COPY (tmp, vp, vsize);
125 vp = (mp_srcptr) tmp;
128 /* Move the dividend to the remainder. */
129 MPN_COPY (rtp, up, usize);
132 q_limb = mpn_divmod (rp, tp, tsize, vp, vsize);
133 rsize = tsize - vsize;
141 r->_mp_size = sign_quotient >= 0 ? rsize : -rsize;