| 1 | /* CGEN generic opcode support. |
| 2 | Copyright (C) 2002-2017 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 * |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 * |
| 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 |
| 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 | } |