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Annotation of OpenXM_contrib/gmp/mpz/lcm_ui.c, Revision 1.1

1.1     ! ohara       1: /* mpz_lcm_ui -- least common multiple of mpz and ulong.
        !             2:
        !             3: Copyright 2001, 2002 Free Software Foundation, Inc.
        !             4:
        !             5: This file is part of the GNU MP Library.
        !             6:
        !             7: The GNU MP Library is free software; you can redistribute it and/or modify
        !             8: it under the terms of the GNU Lesser General Public License as published by
        !             9: the Free Software Foundation; either version 2.1 of the License, or (at your
        !            10: option) any later version.
        !            11:
        !            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 Lesser General Public
        !            15: License for more details.
        !            16:
        !            17: You should have received a copy of the GNU Lesser 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. */
        !            21:
        !            22: #include "gmp.h"
        !            23: #include "gmp-impl.h"
        !            24: #include "longlong.h"
        !            25:
        !            26:
        !            27: void
        !            28: mpz_lcm_ui (mpz_ptr r, mpz_srcptr u, unsigned long v)
        !            29: {
        !            30:   mp_size_t      usize;
        !            31:   mp_srcptr      up;
        !            32:   mp_ptr         rp;
        !            33:   unsigned long  g;
        !            34:   mp_limb_t      c;
        !            35:
        !            36: #if GMP_NAIL_BITS != 0
        !            37:   if (v > GMP_NUMB_MAX)
        !            38:     {
        !            39:       mpz_t vz;
        !            40:       mp_limb_t vlimbs[2];
        !            41:       vlimbs[0] = v & GMP_NUMB_MASK;
        !            42:       vlimbs[1] = v >> GMP_NUMB_BITS;
        !            43:       PTR(vz) = vlimbs;
        !            44:       SIZ(vz) = 2;
        !            45:       mpz_lcm (r, u, vz);
        !            46:       return;
        !            47:     }
        !            48: #endif
        !            49:
        !            50:   /* result zero if either operand zero */
        !            51:   usize = SIZ(u);
        !            52:   if (usize == 0 || v == 0)
        !            53:     {
        !            54:       SIZ(r) = 0;
        !            55:       return;
        !            56:     }
        !            57:   usize = ABS(usize);
        !            58:
        !            59:   MPZ_REALLOC (r, usize+1);
        !            60:
        !            61:   up = PTR(u);
        !            62:   g = (unsigned long) mpn_gcd_1 (up, usize, (mp_limb_t) v);
        !            63:   v /= g;
        !            64:
        !            65:   rp = PTR(r);
        !            66:   c = mpn_mul_1 (rp, up, usize, (mp_limb_t) v);
        !            67:   rp[usize] = c;
        !            68:   usize += (c != 0);
        !            69:   SIZ(r) = usize;
        !            70: }