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

1.1     ! ohara       1: /* mpz_cmpabs_d -- compare absolute values of mpz and double.
        !             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:
        !            23: #include "gmp.h"
        !            24: #include "gmp-impl.h"
        !            25:
        !            26:
        !            27: #define RETURN_CMP(zl, dl)                      \
        !            28:   do {                                          \
        !            29:     zlimb = (zl);                               \
        !            30:     dlimb = (dl);                               \
        !            31:     if (zlimb != dlimb)                         \
        !            32:       return (zlimb >= dlimb ? ret : -ret);     \
        !            33:   } while (0)
        !            34:
        !            35: #define RETURN_NONZERO(ptr, size, val)          \
        !            36:   do {                                          \
        !            37:     mp_size_t __i;                              \
        !            38:     for (__i = (size)-1; __i >= 0; __i--)       \
        !            39:       if ((ptr)[__i] != 0)                      \
        !            40:         return val;                             \
        !            41:     return 0;                                   \
        !            42:   } while (0)
        !            43:
        !            44:
        !            45: int
        !            46: mpz_cmp_d (mpz_srcptr z, double d)
        !            47: {
        !            48:   mp_limb_t  darray[LIMBS_PER_DOUBLE], zlimb, dlimb;
        !            49:   mp_srcptr  zp;
        !            50:   mp_size_t  zsize;
        !            51:   int        dexp, ret;
        !            52:
        !            53:   /* 1. Either operand zero. */
        !            54:   zsize = SIZ(z);
        !            55:   if (d == 0.0)
        !            56:     return zsize;
        !            57:   if (zsize == 0)
        !            58:     return (d < 0.0 ? 1 : -1);
        !            59:
        !            60:   /* 2. Opposite signs. */
        !            61:   if (zsize >= 0)
        !            62:     {
        !            63:       if (d < 0.0)
        !            64:         return 1;    /* >=0 cmp <0 */
        !            65:       ret = 1;
        !            66:     }
        !            67:   else
        !            68:     {
        !            69:       if (d >= 0.0)
        !            70:         return -1;   /* <0 cmp >=0 */
        !            71:       ret = -1;
        !            72:       d = -d;
        !            73:       zsize = -zsize;
        !            74:     }
        !            75:
        !            76:   /* 3. Small d, knowing abs(z) >= 1. */
        !            77:   if (d < 1.0)
        !            78:     return ret;
        !            79:
        !            80:   dexp = __gmp_extract_double (darray, d);
        !            81:   ASSERT (dexp >= 1);
        !            82:
        !            83:   /* 4. Different high limb positions. */
        !            84:   if (zsize != dexp)
        !            85:     return (zsize >= dexp ? ret : -ret);
        !            86:
        !            87:   /* 5. Limb data. */
        !            88:   zp = PTR(z);
        !            89:
        !            90: #if LIMBS_PER_DOUBLE == 2
        !            91:   RETURN_CMP (zp[zsize-1], darray[1]);
        !            92:   if (zsize == 1)
        !            93:     return (darray[0] != 0 ? -ret : 0);
        !            94:
        !            95:   RETURN_CMP (zp[zsize-2], darray[0]);
        !            96:   RETURN_NONZERO (zp, zsize-2, ret);
        !            97:
        !            98: #else
        !            99: #if LIMBS_PER_DOUBLE == 3
        !           100:   RETURN_CMP (zp[zsize-1], darray[2]);
        !           101:   if (zsize == 1)
        !           102:     return ((darray[0] | darray[1]) != 0 ? -ret : 0);
        !           103:
        !           104:   RETURN_CMP (zp[zsize-2], darray[1]);
        !           105:   if (zsize == 2)
        !           106:     return (darray[0] != 0 ? -ret : 0);
        !           107:
        !           108:   RETURN_CMP (zp[zsize-3], darray[0]);
        !           109:   RETURN_NONZERO (zp, zsize-3, ret);
        !           110:
        !           111: #else
        !           112:   for (i = 1; i <= LIMBS_PER_DOUBLE; i++)
        !           113:     {
        !           114:       RETURN_CMP (zp[zsize-i], darray[LIMBS_PER_DOUBLE-i]);
        !           115:       if (i >= zsize)
        !           116:         RETURN_NONZERO (darray, LIMBS_PER_DOUBLE-i, -ret);
        !           117:     }
        !           118:   RETURN_NONZERO (zp, zsize-LIMBS_PER_DOUBLE, ret);
        !           119: #endif
        !           120: #endif
        !           121: }