Annotation of OpenXM_contrib/gmp/mpz/tdiv_qr_ui.c, Revision 1.1.1.3
1.1 maekawa 1: /* mpz_tdiv_qr_ui(quot,rem,dividend,short_divisor) --
2: Set QUOT to DIVIDEND / SHORT_DIVISOR
3: and REM to DIVIDEND mod SHORT_DIVISOR.
4:
1.1.1.3 ! ohara 5: Copyright 1991, 1993, 1994, 1996, 1998, 2001, 2002 Free Software Foundation,
! 6: 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:
1.1.1.2 maekawa 28: unsigned long int
1.1 maekawa 29: mpz_tdiv_qr_ui (mpz_ptr quot, mpz_ptr rem, mpz_srcptr dividend, unsigned long int divisor)
30: {
1.1.1.3 ! ohara 31: mp_size_t ns, nn, qn;
! 32: mp_ptr np, qp;
! 33: mp_limb_t rl;
1.1 maekawa 34:
1.1.1.2 maekawa 35: if (divisor == 0)
36: DIVIDE_BY_ZERO;
37:
1.1.1.3 ! ohara 38: ns = SIZ(dividend);
! 39: if (ns == 0)
! 40: {
! 41: SIZ(quot) = 0;
! 42: SIZ(rem) = 0;
! 43: return 0;
! 44: }
1.1 maekawa 45:
1.1.1.3 ! ohara 46: nn = ABS(ns);
! 47: MPZ_REALLOC (quot, nn);
! 48: qp = PTR(quot);
! 49: np = PTR(dividend);
1.1 maekawa 50:
1.1.1.3 ! ohara 51: #if GMP_NAIL_BITS != 0
! 52: if (divisor > GMP_NUMB_MAX)
! 53: {
! 54: mp_limb_t dp[2];
! 55: mp_ptr rp;
! 56: mp_size_t rn;
! 57:
! 58: if (nn == 1) /* tdiv_qr requirements; tested above for 0 */
! 59: {
! 60: SIZ(quot) = 0;
! 61: rl = np[0];
! 62: SIZ(rem) = ns >= 0 ? 1 : -1;
! 63: PTR(rem)[0] = rl;
! 64: return rl;
! 65: }
! 66:
! 67: MPZ_REALLOC (rem, 2);
! 68: rp = PTR(rem);
! 69:
! 70: dp[0] = divisor & GMP_NUMB_MASK;
! 71: dp[1] = divisor >> GMP_NUMB_BITS;
! 72: mpn_tdiv_qr (qp, rp, (mp_size_t) 0, np, nn, dp, (mp_size_t) 2);
! 73: rl = rp[0] + (rp[1] << GMP_NUMB_BITS);
! 74: qn = nn - 2 + 1; qn -= qp[qn - 1] == 0; qn -= qn != 0 && qp[qn - 1] == 0;
! 75: rn = 2 - (rp[1] == 0); rn -= (rp[rn - 1] == 0);
! 76: SIZ(rem) = ns >= 0 ? rn : -rn;
! 77: }
1.1 maekawa 78: else
1.1.1.3 ! ohara 79: #endif
1.1 maekawa 80: {
1.1.1.3 ! ohara 81: rl = mpn_divrem_1 (qp, (mp_size_t) 0, np, nn, (mp_limb_t) divisor);
! 82: if (rl == 0)
! 83: SIZ(rem) = 0;
! 84: else
! 85: {
! 86: /* Store the single-limb remainder. We don't check if there's space
! 87: for just one limb, since no function ever makes zero space. */
! 88: SIZ(rem) = ns >= 0 ? 1 : -1;
! 89: PTR(rem)[0] = rl;
! 90: }
! 91: qn = nn - (qp[nn - 1] == 0);
1.1 maekawa 92: }
93:
1.1.1.3 ! ohara 94: SIZ(quot) = ns >= 0 ? qn : -qn;
! 95: return rl;
1.1 maekawa 96: }
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