1/* Implement POWERSET runtime actions for CHILL.
2   Copyright (C) 1992,1993 Free Software Foundation, Inc.
3   Author: Wilfried Moser, et al
4
5This file is part of GNU CC.
6
7GNU CC is free software; you can redistribute it and/or modify
8it under the terms of the GNU General Public License as published by
9the Free Software Foundation; either version 2, or (at your option)
10any later version.
11
12GNU CC is distributed in the hope that it will be useful,
13but WITHOUT ANY WARRANTY; without even the implied warranty of
14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15GNU General Public License for more details.
16
17You should have received a copy of the GNU General Public License
18along with GNU CC; see the file COPYING.  If not, write to
19the Free Software Foundation, 59 Temple Place - Suite 330,
20Boston, MA 02111-1307, USA.  */
21
22/* As a special exception, if you link this library with other files,
23   some of which are compiled with GCC, to produce an executable,
24   this library does not by itself cause the resulting executable
25   to be covered by the GNU General Public License.
26   This exception does not however invalidate any other reasons why
27   the executable file might be covered by the GNU General Public License.  */
28
29#define __CHILL_LIB__
30
31#include <stdio.h>
32#include "powerset.h"
33
34/*
35 * function __xorpowerset
36 *
37 * parameters:
38 *	out		return from __xorpowerset
39 *	left		left powerset
40 *	right		right powerset
41 *	bitlength	length of powerset in bits
42 *
43 * returns:
44 *	void
45 *
46 * exceptions:
47 *  none
48 *
49 * abstract:
50 *  xor's 2 powersets
51 *
52 */
53
54void
55__xorpowerset (out, left, right, bitlength)
56     SET_WORD      *out;
57     SET_WORD      *left;
58     SET_WORD      *right;
59     unsigned long  bitlength;
60{
61  if (bitlength <= SET_CHAR_SIZE)
62    {
63      *((SET_CHAR *)out) = *((SET_CHAR *)left) ^
64                           *((SET_CHAR *)right);
65      MASK_UNUSED_CHAR_BITS((SET_CHAR *)out, bitlength);
66    }
67  else if (bitlength <= SET_SHORT_SIZE)
68    {
69      *((SET_SHORT *)out) = *((SET_SHORT *)left) ^
70                            *((SET_SHORT *)right);
71      MASK_UNUSED_SHORT_BITS((SET_SHORT *)out, bitlength);
72    }
73  else
74    {
75      unsigned long len = BITS_TO_WORDS(bitlength);
76      register unsigned long i;
77
78      for (i = 0; i < len; i++)
79	out[i] = left[i] ^ right[i];
80      MASK_UNUSED_WORD_BITS ((out + len - 1),
81			     bitlength % SET_WORD_SIZE);
82    }
83}
84