Return to fits_u.h CVS log

Up to [local] / OpenXM_contrib / gmp / mpf

Annotation of OpenXM_contrib/gmp/mpf/fits_u.h, Revision 1.1.1.1

1.1       ohara       1: /* mpf_fits_u*_p -- test whether an mpf fits a C unsigned type.
                      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:
                     25:
                     26: /* Notice this is equivalent to mpz_set_f + mpz_fits_u*_p.  */
                     27:
                     28: int
                     29: FUNCTION (mpf_srcptr f)
                     30: {
                     31:   mp_size_t  fn;
                     32:   mp_srcptr  fp;
                     33:   mp_exp_t   exp;
                     34:   mp_limb_t  fl;
                     35:
                     36:   fn = SIZ(f);
                     37:   if (fn <= 0)
                     38:     return fn == 0;  /* zero fits, negatives don't */
                     39:
                     40:   exp = EXP(f);
                     41:   if (exp < 1)
                     42:     return 1;  /* 0 < f < 1 truncates to zero, so fits */
                     43:
                     44:   fp = PTR(f);
                     45:
                     46:   if (exp == 1)
                     47:     {
                     48:       fl = fp[fn-1];
                     49:     }
                     50: #if GMP_NAIL_BITS != 0
                     51:   else if (exp == 2 && MAXIMUM > GMP_NUMB_MAX)
                     52:     {
                     53:       fl = fp[fn-1];
                     54:       if ((fl >> GMP_NAIL_BITS) != 0)
                     55:        return 0;
                     56:       fl = (fl << GMP_NUMB_BITS);
                     57:       if (fn >= 2)
                     58:         fl |= fp[fn-2];
                     59:     }
                     60: #endif
                     61:   else
                     62:     return 0;
                     63:
                     64:   return fl <= MAXIMUM;
                     65: }