1 /* flonum_copy.c - copy a flonum
2    Copyright (C) 1987-2016 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 3, 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 the Free
18    Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
19    02110-1301, USA.  */
20 
21 #include "as.h"
22 
23 void
flonum_copy(FLONUM_TYPE * in,FLONUM_TYPE * out)24 flonum_copy (FLONUM_TYPE *in, FLONUM_TYPE *out)
25 {
26   unsigned int in_length;	/* 0 origin */
27   unsigned int out_length;	/* 0 origin */
28 
29   out->sign = in->sign;
30   in_length = in->leader - in->low;
31 
32   if (in->leader < in->low)
33     {
34       out->leader = out->low - 1;	/* 0.0 case */
35     }
36   else
37     {
38       out_length = out->high - out->low;
39       /* Assume no GAPS in packing of littlenums.
40 	 I.e. sizeof(array) == sizeof(element) * number_of_elements.  */
41       if (in_length <= out_length)
42 	{
43 	  {
44 	    /* For defensive programming, zero any high-order
45 	       littlenums we don't need.  This is destroying evidence
46 	       and wasting time, so why bother???  */
47 	    if (in_length < out_length)
48 	      {
49 		memset ((char *) (out->low + in_length + 1), '\0',
50 			out_length - in_length);
51 	      }
52 	  }
53 	  memcpy ((void *) (out->low), (void *) (in->low),
54 		  ((in_length + 1) * sizeof (LITTLENUM_TYPE)));
55 	  out->exponent = in->exponent;
56 	  out->leader = in->leader - in->low + out->low;
57 	}
58       else
59 	{
60 	  int shorten;		/* 1-origin. Number of littlenums we drop.  */
61 
62 	  shorten = in_length - out_length;
63 	  /* Assume out_length >= 0 ! */
64 	  memcpy ((void *) (out->low), (void *) (in->low + shorten),
65 		  ((out_length + 1) * sizeof (LITTLENUM_TYPE)));
66 	  out->leader = out->high;
67 	  out->exponent = in->exponent + shorten;
68 	}
69     }				/* if any significant bits */
70 }
71