1 /* mpf_ui_div -- Divide an unsigned integer with a float.
3 Copyright (C) 1993, 1994, 1995, 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_ui_div (mpf_ptr r, unsigned long int u, mpf_srcptr v)
39 mp_size_t rsize, tsize;
40 mp_size_t sign_quotient;
42 unsigned normalization_steps;
48 sign_quotient = vsize;
53 vsize = 1 / vsize; /* divide by zero as directed */
62 rexp = 1 - v->_mp_exp;
74 tp = (mp_ptr) TMP_ALLOC ((tsize + 1) * BYTES_PER_MP_LIMB);
77 count_leading_zeros (normalization_steps, vp[vsize - 1]);
79 /* Normalize the divisor and the dividend. */
80 if (normalization_steps != 0)
83 mp_limb_t dividend_high, dividend_low;
85 /* Shift up the divisor setting the most significant bit of
86 the most significant limb. Use temporary storage not to clobber
87 the original contents of the divisor. */
88 tmp = (mp_ptr) TMP_ALLOC (vsize * BYTES_PER_MP_LIMB);
89 mpn_lshift (tmp, vp, vsize, normalization_steps);
92 /* Shift up the dividend, possibly introducing a new most
94 dividend_high = (mp_limb_t) u >> (BITS_PER_MP_LIMB - normalization_steps);
95 dividend_low = (mp_limb_t) u << normalization_steps;
97 tp[tsize - 1] = dividend_low;
98 if (dividend_high != 0)
100 tp[tsize] = dividend_high;
107 /* The divisor is already normalized, as required.
108 Copy it to temporary space if it overlaps with the quotient. */
109 if (vp - rp <= tsize - vsize)
111 mp_ptr tmp = (mp_ptr) TMP_ALLOC (vsize * BYTES_PER_MP_LIMB);
112 MPN_COPY (tmp, vp, vsize);
113 vp = (mp_srcptr) tmp;
119 q_limb = mpn_divmod (rp, tp, tsize, vp, vsize);
120 rsize = tsize - vsize;
128 r->_mp_size = sign_quotient >= 0 ? rsize : -rsize;