1 /* CGEN generic opcode support. 2 3 Copyright 2002, 2005 4 Free Software Foundation, Inc. 5 6 This file is part of the GNU Binutils and GDB, the GNU debugger. 7 8 This program is free software; you can redistribute it and/or modify 9 it under the terms of the GNU General Public License as published by 10 the Free Software Foundation; either version 2, or (at your option) 11 any later version. 12 13 This program is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 You should have received a copy of the GNU General Public License along 19 with this program; if not, write to the Free Software Foundation, Inc., 20 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */ 21 22 /* Functions for manipulating CGEN_BITSET. */ 23 24 #include "libiberty.h" 25 #include "opcode/cgen-bitset.h" 26 #include <string.h> 27 28 /* Create a bit mask. */ 29 CGEN_BITSET * 30 cgen_bitset_create (unsigned bit_count) 31 { 32 CGEN_BITSET * mask = xmalloc (sizeof (* mask)); 33 cgen_bitset_init (mask, bit_count); 34 return mask; 35 } 36 37 /* Initialize an existing bit mask. */ 38 39 void 40 cgen_bitset_init (CGEN_BITSET * mask, unsigned bit_count) 41 { 42 if (! mask) 43 return; 44 mask->length = (bit_count / 8) + 1; 45 mask->bits = xmalloc (mask->length); 46 cgen_bitset_clear (mask); 47 } 48 49 /* Clear the bits of a bit mask. */ 50 51 void 52 cgen_bitset_clear (CGEN_BITSET * mask) 53 { 54 unsigned i; 55 56 if (! mask) 57 return; 58 59 for (i = 0; i < mask->length; ++i) 60 mask->bits[i] = 0; 61 } 62 63 /* Add a bit to a bit mask. */ 64 65 void 66 cgen_bitset_add (CGEN_BITSET * mask, unsigned bit_num) 67 { 68 int byte_ix, bit_ix; 69 int bit_mask; 70 71 if (! mask) 72 return; 73 byte_ix = bit_num / 8; 74 bit_ix = bit_num % 8; 75 bit_mask = 1 << (7 - bit_ix); 76 mask->bits[byte_ix] |= bit_mask; 77 } 78 79 /* Set a bit mask. */ 80 81 void 82 cgen_bitset_set (CGEN_BITSET * mask, unsigned bit_num) 83 { 84 if (! mask) 85 return; 86 cgen_bitset_clear (mask); 87 cgen_bitset_add (mask, bit_num); 88 } 89 90 /* Test for a bit in a bit mask. 91 Returns 1 if the bit is found */ 92 93 int 94 cgen_bitset_contains (CGEN_BITSET * mask, unsigned bit_num) 95 { 96 int byte_ix, bit_ix; 97 int bit_mask; 98 99 if (! mask) 100 return 1; /* No bit restrictions. */ 101 102 byte_ix = bit_num / 8; 103 bit_ix = 7 - (bit_num % 8); 104 bit_mask = 1 << bit_ix; 105 return (mask->bits[byte_ix] & bit_mask) >> bit_ix; 106 } 107 108 /* Compare two bit masks for equality. 109 Returns 0 if they are equal. */ 110 111 int 112 cgen_bitset_compare (CGEN_BITSET * mask1, CGEN_BITSET * mask2) 113 { 114 if (mask1 == mask2) 115 return 0; 116 if (! mask1 || ! mask2) 117 return 1; 118 if (mask1->length != mask2->length) 119 return 1; 120 return memcmp (mask1->bits, mask2->bits, mask1->length); 121 } 122 123 /* Test two bit masks for common bits. 124 Returns 1 if a common bit is found. */ 125 126 int 127 cgen_bitset_intersect_p (CGEN_BITSET * mask1, CGEN_BITSET * mask2) 128 { 129 unsigned i, limit; 130 131 if (mask1 == mask2) 132 return 1; 133 if (! mask1 || ! mask2) 134 return 0; 135 limit = mask1->length < mask2->length ? mask1->length : mask2->length; 136 137 for (i = 0; i < limit; ++i) 138 if ((mask1->bits[i] & mask2->bits[i])) 139 return 1; 140 141 return 0; 142 } 143 144 /* Make a copy of a bit mask. */ 145 146 CGEN_BITSET * 147 cgen_bitset_copy (CGEN_BITSET * mask) 148 { 149 CGEN_BITSET* newmask; 150 151 if (! mask) 152 return NULL; 153 newmask = cgen_bitset_create ((mask->length * 8) - 1); 154 memcpy (newmask->bits, mask->bits, mask->length); 155 return newmask; 156 } 157 158 /* Combine two bit masks. */ 159 160 void 161 cgen_bitset_union (CGEN_BITSET * mask1, CGEN_BITSET * mask2, 162 CGEN_BITSET * result) 163 { 164 unsigned i; 165 166 if (! mask1 || ! mask2 || ! result 167 || mask1->length != mask2->length 168 || mask1->length != result->length) 169 return; 170 171 for (i = 0; i < result->length; ++i) 172 result->bits[i] = mask1->bits[i] | mask2->bits[i]; 173 } 174