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Annotation of OpenXM_contrib/gmp/mpz/cmpabs_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 ? 1 : -1); \
        !            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_cmpabs_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;
        !            52:
        !            53:   /* 1. Check for either operand zero. */
        !            54:   zsize = SIZ(z);
        !            55:   if (d == 0.0)
        !            56:     return (zsize != 0);
        !            57:   if (zsize == 0)
        !            58:     return (d != 0 ? -1 : 0);
        !            59:
        !            60:   /* 2. Ignore signs. */
        !            61:   zsize = ABS(zsize);
        !            62:   d = ABS(d);
        !            63:
        !            64:   /* 3. Small d, knowing abs(z) >= 1. */
        !            65:   if (d < 1.0)
        !            66:     return 1;
        !            67:
        !            68:   dexp = __gmp_extract_double (darray, d);
        !            69:   ASSERT (dexp >= 1);
        !            70:
        !            71:   /* 4. Check for different high limb positions. */
        !            72:   if (zsize != dexp)
        !            73:     return (zsize >= dexp ? 1 : -1);
        !            74:
        !            75:   /* 5. Limb data. */
        !            76:   zp = PTR(z);
        !            77:
        !            78: #if LIMBS_PER_DOUBLE == 2
        !            79:   RETURN_CMP (zp[zsize-1], darray[1]);
        !            80:   if (zsize == 1)
        !            81:     return (darray[0] != 0 ? -1 : 0);
        !            82:
        !            83:   RETURN_CMP (zp[zsize-2], darray[0]);
        !            84:   RETURN_NONZERO (zp, zsize-2, 1);
        !            85:
        !            86: #else
        !            87: #if LIMBS_PER_DOUBLE == 3
        !            88:   RETURN_CMP (zp[zsize-1], darray[2]);
        !            89:   if (zsize == 1)
        !            90:     return ((darray[0] | darray[1]) != 0 ? -1 : 0);
        !            91:
        !            92:   RETURN_CMP (zp[zsize-2], darray[1]);
        !            93:   if (zsize == 2)
        !            94:     return (darray[0] != 0 ? -1 : 0);
        !            95:
        !            96:   RETURN_CMP (zp[zsize-3], darray[0]);
        !            97:   RETURN_NONZERO (zp, zsize-3, 1);
        !            98:
        !            99: #else
        !           100:   for (i = 1; i <= LIMBS_PER_DOUBLE; i++)
        !           101:     {
        !           102:       RETURN_CMP (zp[zsize-i], darray[LIMBS_PER_DOUBLE-i]);
        !           103:       if (i >= zsize)
        !           104:         RETURN_NONZERO (darray, LIMBS_PER_DOUBLE-i, -1);
        !           105:     }
        !           106:   RETURN_NONZERO (zp, zsize-LIMBS_PER_DOUBLE, 1);
        !           107: #endif
        !           108: #endif
        !           109: }