diff options
author | Jonathan Gray <jsg@cvs.openbsd.org> | 2015-11-22 02:46:45 +0000 |
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committer | Jonathan Gray <jsg@cvs.openbsd.org> | 2015-11-22 02:46:45 +0000 |
commit | 0784c49c0f8fcc8b3abd4c9286d9fd8bc089dd7d (patch) | |
tree | a6394e3e264a0f80b57f4ce0f5d9526aa543d4b0 /lib/mesa/src/util/bitset.h | |
parent | d91d0007eecf589ea5699e34aa4d748fce2c57b2 (diff) |
import Mesa 11.0.6
Diffstat (limited to 'lib/mesa/src/util/bitset.h')
-rw-r--r-- | lib/mesa/src/util/bitset.h | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/lib/mesa/src/util/bitset.h b/lib/mesa/src/util/bitset.h new file mode 100644 index 000000000..c45281941 --- /dev/null +++ b/lib/mesa/src/util/bitset.h @@ -0,0 +1,135 @@ +/* + * Mesa 3-D graphics library + * + * Copyright (C) 2006 Brian Paul All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included + * in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS + * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR + * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, + * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + */ + +/** + * \file bitset.h + * \brief Bitset of arbitrary size definitions. + * \author Michal Krol + */ + +#ifndef BITSET_H +#define BITSET_H + +#include "util/u_math.h" + +/**************************************************************************** + * generic bitset implementation + */ + +#define BITSET_WORD unsigned int +#define BITSET_WORDBITS (sizeof (BITSET_WORD) * 8) + +/* bitset declarations + */ +#define BITSET_WORDS(bits) (((bits) + BITSET_WORDBITS - 1) / BITSET_WORDBITS) +#define BITSET_DECLARE(name, bits) BITSET_WORD name[BITSET_WORDS(bits)] + +/* bitset operations + */ +#define BITSET_COPY(x, y) memcpy( (x), (y), sizeof (x) ) +#define BITSET_EQUAL(x, y) (memcmp( (x), (y), sizeof (x) ) == 0) +#define BITSET_ZERO(x) memset( (x), 0, sizeof (x) ) +#define BITSET_ONES(x) memset( (x), 0xff, sizeof (x) ) + +#define BITSET_BITWORD(b) ((b) / BITSET_WORDBITS) +#define BITSET_BIT(b) (1 << ((b) % BITSET_WORDBITS)) + +/* single bit operations + */ +#define BITSET_TEST(x, b) ((x)[BITSET_BITWORD(b)] & BITSET_BIT(b)) +#define BITSET_SET(x, b) ((x)[BITSET_BITWORD(b)] |= BITSET_BIT(b)) +#define BITSET_CLEAR(x, b) ((x)[BITSET_BITWORD(b)] &= ~BITSET_BIT(b)) + +#define BITSET_MASK(b) ((b) == BITSET_WORDBITS ? ~0 : BITSET_BIT(b) - 1) +#define BITSET_RANGE(b, e) (BITSET_MASK((e) + 1) & ~BITSET_MASK(b)) + +/* bit range operations + */ +#define BITSET_TEST_RANGE(x, b, e) \ + (BITSET_BITWORD(b) == BITSET_BITWORD(e) ? \ + ((x)[BITSET_BITWORD(b)] & BITSET_RANGE(b, e)) : \ + (assert (!"BITSET_TEST_RANGE: bit range crosses word boundary"), 0)) +#define BITSET_SET_RANGE(x, b, e) \ + (BITSET_BITWORD(b) == BITSET_BITWORD(e) ? \ + ((x)[BITSET_BITWORD(b)] |= BITSET_RANGE(b, e)) : \ + (assert (!"BITSET_SET_RANGE: bit range crosses word boundary"), 0)) +#define BITSET_CLEAR_RANGE(x, b, e) \ + (BITSET_BITWORD(b) == BITSET_BITWORD(e) ? \ + ((x)[BITSET_BITWORD(b)] &= ~BITSET_RANGE(b, e)) : \ + (assert (!"BITSET_CLEAR_RANGE: bit range crosses word boundary"), 0)) + +/* Get first bit set in a bitset. + */ +static inline int +__bitset_ffs(const BITSET_WORD *x, int n) +{ + int i; + + for (i = 0; i < n; i++) { + if (x[i]) + return ffs(x[i]) + BITSET_WORDBITS * i; + } + + return 0; +} + +#define BITSET_FFS(x) __bitset_ffs(x, ARRAY_SIZE(x)) + +static inline unsigned +__bitset_next_set(unsigned i, BITSET_WORD *tmp, + BITSET_WORD *set, unsigned size) +{ + unsigned bit, word; + + /* NOTE: The initial conditions for this function are very specific. At + * the start of the loop, the tmp variable must be set to *set and the + * initial i value set to 0. This way, if there is a bit set in the first + * word, we ignore the i-value and just grab that bit (so 0 is ok, even + * though 0 may be returned). If the first word is 0, then the value of + * `word` will be 0 and we will go on to look at the second word. + */ + word = BITSET_BITWORD(i); + while (*tmp == 0) { + word++; + + if (word >= BITSET_WORDS(size)) + return size; + + *tmp = set[word]; + } + + /* Find the next set bit in the non-zero word */ + bit = ffs(*tmp) - 1; + + /* Unset the bit */ + *tmp &= ~(1ull << bit); + + return word * BITSET_WORDBITS + bit; +} + +#define BITSET_FOREACH_SET(__i, __tmp, __set, __size) \ + for (__tmp = *(__set), __i = 0; \ + (__i = __bitset_next_set(__i, &__tmp, __set, __size)) < __size;) + +#endif |