| /* |
| * 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/bitscan.h" |
| #include "util/macros.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_SIZE(x) (8 * sizeof(x)) // bitset size in bits |
| |
| #define BITSET_BITWORD(b) ((b) / BITSET_WORDBITS) |
| #define BITSET_BIT(b) (1u << ((b) % BITSET_WORDBITS)) |
| |
| /* single bit operations |
| */ |
| #define BITSET_TEST(x, b) (((x)[BITSET_BITWORD(b)] & BITSET_BIT(b)) != 0) |
| #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) ? ~0 : BITSET_BIT(b) - 1) |
| #define BITSET_RANGE(b, e) ((BITSET_MASK((e) + 1)) & ~(BITSET_BIT(b) - 1)) |
| |
| /* logic bit operations |
| */ |
| static inline void |
| __bitset_and(BITSET_WORD *r, const BITSET_WORD *x, const BITSET_WORD *y, unsigned n) |
| { |
| for (unsigned i = 0; i < n; i++) |
| r[i] = x[i] & y[i]; |
| } |
| |
| static inline void |
| __bitset_or(BITSET_WORD *r, const BITSET_WORD *x, const BITSET_WORD *y, unsigned n) |
| { |
| for (unsigned i = 0; i < n; i++) |
| r[i] = x[i] | y[i]; |
| } |
| |
| static inline void |
| __bitset_not(BITSET_WORD *x, unsigned n) |
| { |
| for (unsigned i = 0; i < n; i++) |
| x[i] = ~x[i]; |
| } |
| |
| static inline void |
| __bitset_andnot(BITSET_WORD *r, const BITSET_WORD *x, const BITSET_WORD *y, unsigned n) |
| { |
| for (unsigned i = 0; i < n; i++) |
| r[i] = x[i] & ~y[i]; |
| } |
| |
| #define BITSET_AND(r, x, y) \ |
| do { \ |
| STATIC_ASSERT(ARRAY_SIZE(r) == ARRAY_SIZE(x)); \ |
| STATIC_ASSERT(ARRAY_SIZE(r) == ARRAY_SIZE(y)); \ |
| __bitset_and(r, x, y, ARRAY_SIZE(r)); \ |
| } while (0) |
| |
| #define BITSET_OR(r, x, y) \ |
| do { \ |
| STATIC_ASSERT(ARRAY_SIZE(r) == ARRAY_SIZE(x)); \ |
| STATIC_ASSERT(ARRAY_SIZE(r) == ARRAY_SIZE(y)); \ |
| __bitset_or(r, x, y, ARRAY_SIZE(r)); \ |
| } while (0) |
| |
| #define BITSET_NOT(x) \ |
| __bitset_not(x, ARRAY_SIZE(x)) |
| |
| #define BITSET_ANDNOT(r, x, y) \ |
| do { \ |
| assert(ARRAY_SIZE(r) == ARRAY_SIZE(x)); \ |
| assert(ARRAY_SIZE(r) == ARRAY_SIZE(y)); \ |
| __bitset_andnot(r, x, y, ARRAY_SIZE(r)); \ |
| } while (0) |
| |
| static inline void |
| __bitset_rotate_right(BITSET_WORD *x, unsigned amount, unsigned n) |
| { |
| assert(amount < BITSET_WORDBITS); |
| |
| if (amount == 0) |
| return; |
| |
| for (unsigned i = 0; i < n - 1; i++) { |
| x[i] = (x[i] >> amount) | (x[i + 1] << (BITSET_WORDBITS - amount)); |
| } |
| |
| x[n - 1] = x[n - 1] >> amount; |
| } |
| |
| static inline void |
| __bitset_rotate_left(BITSET_WORD *x, unsigned amount, unsigned n) |
| { |
| assert(amount < BITSET_WORDBITS); |
| |
| if (amount == 0) |
| return; |
| |
| for (int i = n - 1; i > 0; i--) { |
| x[i] = (x[i] << amount) | (x[i - 1] >> (BITSET_WORDBITS - amount)); |
| } |
| |
| x[0] = x[0] << amount; |
| } |
| |
| static inline void |
| __bitset_shr(BITSET_WORD *x, unsigned amount, unsigned n) |
| { |
| const unsigned int words = amount / BITSET_WORDBITS; |
| |
| if (amount == 0) |
| return; |
| |
| if (words) { |
| unsigned i; |
| |
| for (i = 0; i < n - words; i++) |
| x[i] = x[i + words]; |
| |
| while (i < n) |
| x[i++] = 0; |
| |
| amount %= BITSET_WORDBITS; |
| } |
| |
| __bitset_rotate_right(x, amount, n); |
| } |
| |
| |
| static inline void |
| __bitset_shl(BITSET_WORD *x, unsigned amount, unsigned n) |
| { |
| const int words = amount / BITSET_WORDBITS; |
| |
| if (amount == 0) |
| return; |
| |
| if (words) { |
| int i; |
| |
| for (i = n - 1; i >= words; i--) { |
| x[i] = x[i - words]; |
| } |
| |
| while (i >= 0) { |
| x[i--] = 0; |
| } |
| |
| amount %= BITSET_WORDBITS; |
| } |
| |
| __bitset_rotate_left(x, amount, n); |
| } |
| |
| #define BITSET_SHR(x, n) \ |
| __bitset_shr(x, n, ARRAY_SIZE(x)); |
| |
| #define BITSET_SHL(x, n) \ |
| __bitset_shl(x, n, ARRAY_SIZE(x)); |
| |
| /* bit range operations |
| */ |
| #define BITSET_TEST_RANGE_INSIDE_WORD(x, b, e) \ |
| (BITSET_BITWORD(b) == BITSET_BITWORD(e) ? \ |
| (((x)[BITSET_BITWORD(b)] & BITSET_RANGE(b, e)) != 0) : \ |
| (assert (!"BITSET_TEST_RANGE: bit range crosses word boundary"), 0)) |
| #define BITSET_SET_RANGE_INSIDE_WORD(x, b, e) \ |
| (BITSET_BITWORD(b) == BITSET_BITWORD(e) ? \ |
| ((x)[BITSET_BITWORD(b)] |= BITSET_RANGE(b, e)) : \ |
| (assert (!"BITSET_SET_RANGE_INSIDE_WORD: bit range crosses word boundary"), 0)) |
| #define BITSET_CLEAR_RANGE_INSIDE_WORD(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)) |
| |
| static inline bool |
| __bitset_test_range(const BITSET_WORD *r, unsigned start, unsigned end) |
| { |
| const unsigned size = end - start + 1; |
| const unsigned start_mod = start % BITSET_WORDBITS; |
| |
| if (start_mod + size <= BITSET_WORDBITS) { |
| return BITSET_TEST_RANGE_INSIDE_WORD(r, start, end); |
| } else { |
| const unsigned first_size = BITSET_WORDBITS - start_mod; |
| |
| return __bitset_test_range(r, start, start + first_size - 1) || |
| __bitset_test_range(r, start + first_size, end); |
| } |
| } |
| |
| #define BITSET_TEST_RANGE(x, b, e) \ |
| __bitset_test_range(x, b, e) |
| |
| static inline void |
| __bitset_set_range(BITSET_WORD *r, unsigned start, unsigned end) |
| { |
| const unsigned size = end - start + 1; |
| const unsigned start_mod = start % BITSET_WORDBITS; |
| |
| if (start_mod + size <= BITSET_WORDBITS) { |
| BITSET_SET_RANGE_INSIDE_WORD(r, start, end); |
| } else { |
| const unsigned first_size = BITSET_WORDBITS - start_mod; |
| |
| __bitset_set_range(r, start, start + first_size - 1); |
| __bitset_set_range(r, start + first_size, end); |
| } |
| } |
| |
| #define BITSET_SET_RANGE(x, b, e) \ |
| __bitset_set_range(x, b, e) |
| |
| static inline void |
| __bitclear_clear_range(BITSET_WORD *r, unsigned start, unsigned end) |
| { |
| const unsigned size = end - start + 1; |
| const unsigned start_mod = start % BITSET_WORDBITS; |
| |
| if (start_mod + size <= BITSET_WORDBITS) { |
| BITSET_CLEAR_RANGE_INSIDE_WORD(r, start, end); |
| } else { |
| const unsigned first_size = BITSET_WORDBITS - start_mod; |
| |
| __bitclear_clear_range(r, start, start + first_size - 1); |
| __bitclear_clear_range(r, start + first_size, end); |
| } |
| } |
| |
| #define BITSET_CLEAR_RANGE(x, b, e) \ |
| __bitclear_clear_range(x, b, e) |
| |
| static inline unsigned |
| __bitset_prefix_sum(const BITSET_WORD *x, unsigned b, unsigned n) |
| { |
| unsigned prefix = 0; |
| |
| for (unsigned i = 0; i < n; i++) { |
| if ((i + 1) * BITSET_WORDBITS <= b) { |
| prefix += util_bitcount(x[i]); |
| } else { |
| prefix += util_bitcount(x[i] & BITFIELD_MASK(b - i * BITSET_WORDBITS)); |
| break; |
| } |
| } |
| return prefix; |
| } |
| |
| /* Count set bits in the bitset (compute the size/cardinality of the bitset). |
| * This is a special case of prefix sum, but this convenience method is more |
| * natural when applicable. |
| */ |
| |
| static inline unsigned |
| __bitset_count(const BITSET_WORD *x, unsigned n) |
| { |
| return __bitset_prefix_sum(x, ~0, n); |
| } |
| |
| #define BITSET_PREFIX_SUM(x, b) \ |
| __bitset_prefix_sum(x, b, ARRAY_SIZE(x)) |
| |
| #define BITSET_COUNT(x) \ |
| __bitset_count(x, ARRAY_SIZE(x)) |
| |
| /* Return true if the bitset has no bits set. |
| */ |
| static inline bool |
| __bitset_is_empty(const BITSET_WORD *x, int n) |
| { |
| for (int i = 0; i < n; i++) { |
| if (x[i]) |
| return false; |
| } |
| |
| return true; |
| } |
| |
| /* Get first bit set in a bitset. |
| */ |
| static inline int |
| __bitset_ffs(const BITSET_WORD *x, int n) |
| { |
| for (int i = 0; i < n; i++) { |
| if (x[i]) |
| return ffs(x[i]) + BITSET_WORDBITS * i; |
| } |
| |
| return 0; |
| } |
| |
| /* Get the last bit set in a bitset. |
| */ |
| static inline int |
| __bitset_last_bit(const BITSET_WORD *x, int n) |
| { |
| for (int i = n - 1; i >= 0; i--) { |
| if (x[i]) |
| return util_last_bit(x[i]) + BITSET_WORDBITS * i; |
| } |
| |
| return 0; |
| } |
| |
| #define BITSET_FFS(x) __bitset_ffs(x, ARRAY_SIZE(x)) |
| #define BITSET_LAST_BIT(x) __bitset_last_bit(x, ARRAY_SIZE(x)) |
| #define BITSET_LAST_BIT_SIZED(x, size) __bitset_last_bit(x, size) |
| #define BITSET_IS_EMPTY(x) __bitset_is_empty(x, ARRAY_SIZE(x)) |
| |
| static inline unsigned |
| __bitset_next_set(unsigned i, BITSET_WORD *tmp, |
| const 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; |
| } |
| |
| /** |
| * Iterates over each set bit in a set |
| * |
| * @param __i iteration variable, bit number |
| * @param __set the bitset to iterate (will not be modified) |
| * @param __size number of bits in the set to consider |
| */ |
| #define BITSET_FOREACH_SET(__i, __set, __size) \ |
| for (BITSET_WORD __tmp = (__size) == 0 ? 0 : *(__set), *__foo = &__tmp; __foo != NULL; __foo = NULL) \ |
| for (__i = 0; \ |
| (__i = __bitset_next_set(__i, &__tmp, __set, __size)) < __size;) |
| |
| static inline void |
| __bitset_next_range(unsigned *start, unsigned *end, const BITSET_WORD *set, |
| unsigned size) |
| { |
| /* To find the next start, start searching from end. In the first iteration |
| * it will be at 0, in every subsequent iteration it will be at the first |
| * 0-bit after the range. |
| */ |
| unsigned word = BITSET_BITWORD(*end); |
| if (word >= BITSET_WORDS(size)) { |
| *start = *end = size; |
| return; |
| } |
| BITSET_WORD tmp = set[word] & ~(BITSET_BIT(*end) - 1); |
| while (!tmp) { |
| word++; |
| if (word >= BITSET_WORDS(size)) { |
| *start = *end = size; |
| return; |
| } |
| tmp = set[word]; |
| } |
| |
| *start = word * BITSET_WORDBITS + ffs(tmp) - 1; |
| |
| /* Now do the opposite to find end. Here we can start at start + 1, because |
| * we know that the bit at start is 1 and we're searching for the first |
| * 0-bit. |
| */ |
| word = BITSET_BITWORD(*start + 1); |
| if (word >= BITSET_WORDS(size)) { |
| *end = size; |
| return; |
| } |
| tmp = set[word] | (BITSET_BIT(*start + 1) - 1); |
| while (~tmp == 0) { |
| word++; |
| if (word >= BITSET_WORDS(size)) { |
| *end = size; |
| return; |
| } |
| tmp = set[word]; |
| } |
| |
| /* Cap "end" at "size" in case there are extra bits past "size" set in the |
| * word. This is only necessary for "end" because we terminate the loop if |
| * "start" goes past "size". |
| */ |
| *end = MIN2(word * BITSET_WORDBITS + ffs(~tmp) - 1, size); |
| } |
| |
| /** |
| * Iterates over each contiguous range of set bits in a set |
| * |
| * @param __start the first 1 bit of the current range |
| * @param __end the bit after the last 1 bit of the current range |
| * @param __set the bitset to iterate (will not be modified) |
| * @param __size number of bits in the set to consider |
| */ |
| #define BITSET_FOREACH_RANGE(__start, __end, __set, __size) \ |
| for (__start = 0, __end = 0, \ |
| __bitset_next_range(&__start, &__end, __set, __size); \ |
| __start < __size; \ |
| __bitset_next_range(&__start, &__end, __set, __size)) |
| |
| |
| #ifdef __cplusplus |
| |
| /** |
| * Simple C++ wrapper of a bitset type of static size, with value semantics |
| * and basic bitwise arithmetic operators. The operators defined below are |
| * expected to have the same semantics as the same operator applied to other |
| * fundamental integer types. T is the name of the struct to instantiate |
| * it as, and N is the number of bits in the bitset. |
| */ |
| #define DECLARE_BITSET_T(T, N) struct T { \ |
| explicit \ |
| operator bool() const \ |
| { \ |
| for (unsigned i = 0; i < BITSET_WORDS(N); i++) \ |
| if (words[i]) \ |
| return true; \ |
| return false; \ |
| } \ |
| \ |
| T & \ |
| operator=(int x) \ |
| { \ |
| const T c = {{ (BITSET_WORD)x }}; \ |
| return *this = c; \ |
| } \ |
| \ |
| friend bool \ |
| operator==(const T &b, const T &c) \ |
| { \ |
| return BITSET_EQUAL(b.words, c.words); \ |
| } \ |
| \ |
| friend bool \ |
| operator!=(const T &b, const T &c) \ |
| { \ |
| return !(b == c); \ |
| } \ |
| \ |
| friend bool \ |
| operator==(const T &b, int x) \ |
| { \ |
| const T c = {{ (BITSET_WORD)x }}; \ |
| return b == c; \ |
| } \ |
| \ |
| friend bool \ |
| operator!=(const T &b, int x) \ |
| { \ |
| return !(b == x); \ |
| } \ |
| \ |
| friend T \ |
| operator~(const T &b) \ |
| { \ |
| T c; \ |
| for (unsigned i = 0; i < BITSET_WORDS(N); i++) \ |
| c.words[i] = ~b.words[i]; \ |
| return c; \ |
| } \ |
| \ |
| T & \ |
| operator|=(const T &b) \ |
| { \ |
| for (unsigned i = 0; i < BITSET_WORDS(N); i++) \ |
| words[i] |= b.words[i]; \ |
| return *this; \ |
| } \ |
| \ |
| friend T \ |
| operator|(const T &b, const T &c) \ |
| { \ |
| T d = b; \ |
| d |= c; \ |
| return d; \ |
| } \ |
| \ |
| T & \ |
| operator&=(const T &b) \ |
| { \ |
| for (unsigned i = 0; i < BITSET_WORDS(N); i++) \ |
| words[i] &= b.words[i]; \ |
| return *this; \ |
| } \ |
| \ |
| friend T \ |
| operator&(const T &b, const T &c) \ |
| { \ |
| T d = b; \ |
| d &= c; \ |
| return d; \ |
| } \ |
| \ |
| bool \ |
| test(unsigned i) const \ |
| { \ |
| return BITSET_TEST(words, i); \ |
| } \ |
| \ |
| T & \ |
| set(unsigned i) \ |
| { \ |
| BITSET_SET(words, i); \ |
| return *this; \ |
| } \ |
| \ |
| T & \ |
| clear(unsigned i) \ |
| { \ |
| BITSET_CLEAR(words, i); \ |
| return *this; \ |
| } \ |
| \ |
| BITSET_WORD words[BITSET_WORDS(N)]; \ |
| } |
| |
| #endif |
| |
| #endif |
