Annotation of OpenXM_contrib/gmp/mpz/cdiv_r_ui.c, Revision 1.1.1.3
1.1 maekawa 1: /* mpz_cdiv_r_ui -- Division rounding the quotient towards +infinity. The
2: remainder gets the opposite sign as the denominator. In order to make it
3: always fit into the return type, the negative of the true remainder is
4: returned.
5:
1.1.1.3 ! ohara 6: Copyright 1994, 1995, 1996, 2001, 2002 Free Software Foundation, Inc.
1.1 maekawa 7:
8: This file is part of the GNU MP Library.
9:
10: The GNU MP Library is free software; you can redistribute it and/or modify
1.1.1.2 maekawa 11: it under the terms of the GNU Lesser General Public License as published by
12: the Free Software Foundation; either version 2.1 of the License, or (at your
1.1 maekawa 13: option) any later version.
14:
15: The GNU MP Library is distributed in the hope that it will be useful, but
16: WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
1.1.1.2 maekawa 17: or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
1.1 maekawa 18: License for more details.
19:
1.1.1.2 maekawa 20: You should have received a copy of the GNU Lesser General Public License
1.1 maekawa 21: along with the GNU MP Library; see the file COPYING.LIB. If not, write to
22: the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
23: MA 02111-1307, USA. */
24:
25: #include "gmp.h"
26: #include "gmp-impl.h"
27:
28: unsigned long int
29: mpz_cdiv_r_ui (mpz_ptr rem, mpz_srcptr dividend, unsigned long int divisor)
30: {
1.1.1.3 ! ohara 31: mp_size_t ns, nn;
! 32: mp_ptr np;
! 33: mp_limb_t rl;
1.1.1.2 maekawa 34:
35: if (divisor == 0)
36: DIVIDE_BY_ZERO;
1.1 maekawa 37:
1.1.1.3 ! ohara 38: ns = SIZ(dividend);
! 39: if (ns == 0)
! 40: {
! 41: SIZ(rem) = 0;
! 42: return 0;
! 43: }
! 44:
! 45: nn = ABS(ns);
! 46: np = PTR(dividend);
! 47: #if GMP_NAIL_BITS != 0
! 48: if (divisor > GMP_NUMB_MAX)
! 49: {
! 50: mp_limb_t dp[2];
! 51: mp_ptr rp, qp;
! 52: mp_size_t rn;
! 53: TMP_DECL (mark);
! 54:
! 55: MPZ_REALLOC (rem, 2);
! 56: rp = PTR(rem);
! 57:
! 58: if (nn == 1) /* tdiv_qr requirements; tested above for 0 */
! 59: {
! 60: rl = np[0];
! 61: rp[0] = rl;
! 62: }
! 63: else
! 64: {
! 65: TMP_MARK (mark);
! 66: dp[0] = divisor & GMP_NUMB_MASK;
! 67: dp[1] = divisor >> GMP_NUMB_BITS;
! 68: qp = TMP_ALLOC_LIMBS (nn - 2 + 1);
! 69: mpn_tdiv_qr (qp, rp, (mp_size_t) 0, np, nn, dp, (mp_size_t) 2);
! 70: TMP_FREE (mark);
! 71: rl = rp[0] + (rp[1] << GMP_NUMB_BITS);
! 72: }
! 73:
! 74: if (rl != 0 && ns >= 0)
! 75: {
! 76: rl = divisor - rl;
! 77: rp[0] = rl & GMP_NUMB_MASK;
! 78: rp[1] = rl >> GMP_NUMB_BITS;
! 79: }
! 80:
! 81: rn = 1 + (rl > GMP_NUMB_MAX); rn -= (rp[rn - 1] == 0);
! 82: SIZ(rem) = -rn;
! 83: }
! 84: else
! 85: #endif
! 86: {
! 87: rl = mpn_mod_1 (np, nn, (mp_limb_t) divisor);
! 88: if (rl == 0)
! 89: SIZ(rem) = 0;
! 90: else
! 91: {
! 92: if (ns >= 0)
! 93: rl = divisor - rl;
! 94:
! 95: PTR(rem)[0] = rl;
! 96: SIZ(rem) = -1;
! 97: }
! 98: }
1.1 maekawa 99:
1.1.1.3 ! ohara 100: return rl;
1.1 maekawa 101: }
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