1 /* CGEN generic opcode support.
2 Copyright (C) 2002-2016 Free Software Foundation, Inc.
3
4 This file is part of libopcodes.
5
6 This library 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 It is distributed in the hope that it will be useful, but WITHOUT
12 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
13 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
14 License for more details.
15
16 You should have received a copy of the GNU General Public License along
17 with this program; if not, write to the Free Software Foundation, Inc.,
18 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
19
20 /* Functions for manipulating CGEN_BITSET. */
21
22 #include "libiberty.h"
23 #include "cgen/bitset.h"
24 #include <string.h>
25
26 /* Create a bit mask. */
27
28 CGEN_BITSET *
cgen_bitset_create(unsigned bit_count)29 cgen_bitset_create (unsigned bit_count)
30 {
31 CGEN_BITSET * mask = xmalloc (sizeof (* mask));
32 cgen_bitset_init (mask, bit_count);
33 return mask;
34 }
35
36 /* Initialize an existing bit mask. */
37
38 void
cgen_bitset_init(CGEN_BITSET * mask,unsigned bit_count)39 cgen_bitset_init (CGEN_BITSET * mask, unsigned bit_count)
40 {
41 if (! mask)
42 return;
43 mask->length = (bit_count / 8) + 1;
44 mask->bits = xmalloc (mask->length);
45 cgen_bitset_clear (mask);
46 }
47
48 /* Clear the bits of a bit mask. */
49
50 void
cgen_bitset_clear(CGEN_BITSET * mask)51 cgen_bitset_clear (CGEN_BITSET * mask)
52 {
53 unsigned i;
54
55 if (! mask)
56 return;
57
58 for (i = 0; i < mask->length; ++i)
59 mask->bits[i] = 0;
60 }
61
62 /* Add a bit to a bit mask. */
63
64 void
cgen_bitset_add(CGEN_BITSET * mask,unsigned bit_num)65 cgen_bitset_add (CGEN_BITSET * mask, unsigned bit_num)
66 {
67 int byte_ix, bit_ix;
68 int bit_mask;
69
70 if (! mask)
71 return;
72 byte_ix = bit_num / 8;
73 bit_ix = bit_num % 8;
74 bit_mask = 1 << (7 - bit_ix);
75 mask->bits[byte_ix] |= bit_mask;
76 }
77
78 /* Set a bit mask. */
79
80 void
cgen_bitset_set(CGEN_BITSET * mask,unsigned bit_num)81 cgen_bitset_set (CGEN_BITSET * mask, unsigned bit_num)
82 {
83 if (! mask)
84 return;
85 cgen_bitset_clear (mask);
86 cgen_bitset_add (mask, bit_num);
87 }
88
89 /* Test for a bit in a bit mask.
90 Returns 1 if the bit is found */
91
92 int
cgen_bitset_contains(CGEN_BITSET * mask,unsigned bit_num)93 cgen_bitset_contains (CGEN_BITSET * mask, unsigned bit_num)
94 {
95 int byte_ix, bit_ix;
96 int bit_mask;
97
98 if (! mask)
99 return 1; /* No bit restrictions. */
100
101 byte_ix = bit_num / 8;
102 bit_ix = 7 - (bit_num % 8);
103 bit_mask = 1 << bit_ix;
104 return (mask->bits[byte_ix] & bit_mask) >> bit_ix;
105 }
106
107 /* Compare two bit masks for equality.
108 Returns 0 if they are equal. */
109
110 int
cgen_bitset_compare(CGEN_BITSET * mask1,CGEN_BITSET * mask2)111 cgen_bitset_compare (CGEN_BITSET * mask1, CGEN_BITSET * mask2)
112 {
113 if (mask1 == mask2)
114 return 0;
115 if (! mask1 || ! mask2)
116 return 1;
117 if (mask1->length != mask2->length)
118 return 1;
119 return memcmp (mask1->bits, mask2->bits, mask1->length);
120 }
121
122 /* Test two bit masks for common bits.
123 Returns 1 if a common bit is found. */
124
125 int
cgen_bitset_intersect_p(CGEN_BITSET * mask1,CGEN_BITSET * mask2)126 cgen_bitset_intersect_p (CGEN_BITSET * mask1, CGEN_BITSET * mask2)
127 {
128 unsigned i, limit;
129
130 if (mask1 == mask2)
131 return 1;
132 if (! mask1 || ! mask2)
133 return 0;
134 limit = mask1->length < mask2->length ? mask1->length : mask2->length;
135
136 for (i = 0; i < limit; ++i)
137 if ((mask1->bits[i] & mask2->bits[i]))
138 return 1;
139
140 return 0;
141 }
142
143 /* Make a copy of a bit mask. */
144
145 CGEN_BITSET *
cgen_bitset_copy(CGEN_BITSET * mask)146 cgen_bitset_copy (CGEN_BITSET * mask)
147 {
148 CGEN_BITSET* newmask;
149
150 if (! mask)
151 return NULL;
152 newmask = cgen_bitset_create ((mask->length * 8) - 1);
153 memcpy (newmask->bits, mask->bits, mask->length);
154 return newmask;
155 }
156
157 /* Combine two bit masks. */
158
159 void
cgen_bitset_union(CGEN_BITSET * mask1,CGEN_BITSET * mask2,CGEN_BITSET * result)160 cgen_bitset_union (CGEN_BITSET * mask1, CGEN_BITSET * mask2,
161 CGEN_BITSET * result)
162 {
163 unsigned i;
164
165 if (! mask1 || ! mask2 || ! result
166 || mask1->length != mask2->length
167 || mask1->length != result->length)
168 return;
169
170 for (i = 0; i < result->length; ++i)
171 result->bits[i] = mask1->bits[i] | mask2->bits[i];
172 }
173