arch/mips/math-emu/dp_frexp.c

   1 /* IEEE754 floating point arithmetic
   2  * double precision: common utilities
   3  */
   4 /*
   5  * MIPS floating point support
   6  * Copyright (C) 1994-2000 Algorithmics Ltd.  All rights reserved.
   7  * http://www.algor.co.uk
   8  *
   9  * ########################################################################
  10  *
  11  *  This program is free software; you can distribute it and/or modify it
  12  *  under the terms of the GNU General Public License (Version 2) as
  13  *  published by the Free Software Foundation.
  14  *
  15  *  This program is distributed in the hope it will be useful, but WITHOUT
  16  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  17  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  18  *  for more details.
  19  *
  20  *  You should have received a copy of the GNU General Public License along
  21  *  with this program; if not, write to the Free Software Foundation, Inc.,
  22  *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
  23  *
  24  * ########################################################################
  25  */
  26
  27
  28 #include "ieee754dp.h"
  29
  30 /* close to ieeep754dp_logb
  31 */
  32 ieee754dp ieee754dp_frexp(ieee754dp x, int *eptr)
  33 {
  34         COMPXDP;
  35         CLEARCX;
  36         EXPLODEXDP;
  37
  38         switch (xc) {
  39         case IEEE754_CLASS_SNAN:
  40         case IEEE754_CLASS_QNAN:
  41         case IEEE754_CLASS_INF:
  42         case IEEE754_CLASS_ZERO:
  43                 *eptr = 0;
  44                 return x;
  45         case IEEE754_CLASS_DNORM:
  46                 DPDNORMX;
  47                 break;
  48         case IEEE754_CLASS_NORM:
  49                 break;
  50         }
  51         *eptr = xe + 1;
  52         return builddp(xs, -1 + DP_EBIAS, xm & ~DP_HIDDEN_BIT);
  53 }