gas/flonum-copy.c

   1 /* flonum_copy.c - copy a flonum
   2    Copyright (C) 1987, 1990, 1991, 1992 Free Software Foundation, Inc.
   3
   4    This file is part of GAS, the GNU Assembler.
   5
   6    GAS is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2, or (at your option)
   9    any later version.
  10
  11    GAS is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with GAS; see the file COPYING.  If not, write to
  18    the Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  19
  20 #include "as.h"
  21
  22 void
  23 flonum_copy (in, out)
  24      FLONUM_TYPE *in;
  25      FLONUM_TYPE *out;
  26 {
  27   unsigned int in_length;               /* 0 origin */
  28   unsigned int out_length;              /* 0 origin */
  29
  30   out->sign = in->sign;
  31   in_length = in->leader - in->low;
  32
  33   if (in->leader < in->low)
  34     {
  35       out->leader = out->low - 1;       /* 0.0 case */
  36     }
  37   else
  38     {
  39       out_length = out->high - out->low;
  40       /*
  41        * Assume no GAPS in packing of littlenums.
  42        * I.e. sizeof(array) == sizeof(element) * number_of_elements.
  43        */
  44       if (in_length <= out_length)
  45         {
  46           {
  47             /*
  48              * For defensive programming, zero any high-order littlenums we don't need.
  49              * This is destroying evidence and wasting time, so why bother???
  50              */
  51             if (in_length < out_length)
  52               {
  53                 memset ((char *) (out->low + in_length + 1), '\0', out_length - in_length);
  54               }
  55           }
  56           memcpy ((void *) (out->low), (void *) (in->low), ((in_length + 1) * sizeof (LITTLENUM_TYPE)));
  57           out->exponent = in->exponent;
  58           out->leader = in->leader - in->low + out->low;
  59         }
  60       else
  61         {
  62           int shorten;          /* 1-origin. Number of littlenums we drop. */
  63
  64           shorten = in_length - out_length;
  65           /* Assume out_length >= 0 ! */
  66           memcpy ((void *) (out->low), (void *) (in->low + shorten), ((out_length + 1) * sizeof (LITTLENUM_TYPE)));
  67           out->leader = out->high;
  68           out->exponent = in->exponent + shorten;
  69         }
  70     }                           /* if any significant bits */
  71 }                               /* flonum_copy() */
  72
  73 /* end of flonum_copy.c */