flonum-copy.c revision 33965 
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
22void
23flonum_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 */
74