gas/flonum-copy.c

   1 /* flonum_copy.c - copy a flonum
   2    Copyright (C) 1987, 1990, 1991 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, 675 Mass Ave, Cambridge, MA 02139, USA.  */
  19
  20 #include "as.h"
  21
  22 #ifdef USG
  23 #define bzero(s,n) memset(s,0,n)
  24 #define bcopy(from,to,n) memcpy(to,from,n)
  25 #endif
  26
  27 void
  28     flonum_copy (in, out)
  29 FLONUM_TYPE *   in;
  30 FLONUM_TYPE *   out;
  31 {
  32         int                     in_length;      /* 0 origin */
  33         int                     out_length;     /* 0 origin */
  34
  35         out -> sign = in -> sign;
  36         in_length = in  -> leader - in -> low;
  37         if (in_length < 0)
  38             {
  39                     out -> leader = out -> low - 1; /* 0.0 case */
  40             }
  41         else
  42             {
  43                     out_length = out -> high - out -> low;
  44                     /*
  45                      * Assume no GAPS in packing of littlenums.
  46                      * I.e. sizeof(array) == sizeof(element) * number_of_elements.
  47                      */
  48                     if (in_length <= out_length)
  49                         {
  50                                 {
  51                                         /*
  52                                          * For defensive programming, zero any high-order littlenums we don't need.
  53                                          * This is destroying evidence and wasting time, so why bother???
  54                                          */
  55                                         if (in_length < out_length)
  56                                             {
  57                                                     bzero ((char *)(out->low + in_length + 1), out_length - in_length);
  58                                             }
  59                                 }
  60                                 bcopy ((char *)(in->low), (char *)(out->low), (int)((in_length + 1) * sizeof(LITTLENUM_TYPE)));
  61                                 out -> exponent = in -> exponent;
  62                                 out -> leader   = in -> leader - in -> low + out -> low;
  63                         }
  64                     else
  65                         {
  66                                 int     shorten;                /* 1-origin. Number of littlenums we drop. */
  67
  68                                 shorten = in_length - out_length;
  69                                 /* Assume out_length >= 0 ! */
  70                                 bcopy ((char *)(in->low + shorten),(char *)( out->low), (int)((out_length + 1) * sizeof(LITTLENUM_TYPE)));
  71                                 out -> leader = out -> high;
  72                                 out -> exponent = in -> exponent + shorten;
  73                         }
  74             }                           /* if any significant bits */
  75 }
  76
  77 /* end of flonum_copy.c */