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Diffstat (limited to 'ewah/ewok_rlw.h')
| -rw-r--r-- | ewah/ewok_rlw.h | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/ewah/ewok_rlw.h b/ewah/ewok_rlw.h new file mode 100644 index 0000000..63efdf9 --- /dev/null +++ b/ewah/ewok_rlw.h @@ -0,0 +1,114 @@ +/** + * Copyright 2013, GitHub, Inc + * Copyright 2009-2013, Daniel Lemire, Cliff Moon, + * David McIntosh, Robert Becho, Google Inc. and Veronika Zenz + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + */ +#ifndef __EWOK_RLW_H__ +#define __EWOK_RLW_H__ + +#define RLW_RUNNING_BITS (sizeof(eword_t) * 4) +#define RLW_LITERAL_BITS (sizeof(eword_t) * 8 - 1 - RLW_RUNNING_BITS) + +#define RLW_LARGEST_RUNNING_COUNT (((eword_t)1 << RLW_RUNNING_BITS) - 1) +#define RLW_LARGEST_LITERAL_COUNT (((eword_t)1 << RLW_LITERAL_BITS) - 1) + +#define RLW_LARGEST_RUNNING_COUNT_SHIFT (RLW_LARGEST_RUNNING_COUNT << 1) + +#define RLW_RUNNING_LEN_PLUS_BIT (((eword_t)1 << (RLW_RUNNING_BITS + 1)) - 1) + +static int rlw_get_run_bit(const eword_t *word) +{ + return *word & (eword_t)1; +} + +static inline void rlw_set_run_bit(eword_t *word, int b) +{ + if (b) { + *word |= (eword_t)1; + } else { + *word &= (eword_t)(~1); + } +} + +static inline void rlw_xor_run_bit(eword_t *word) +{ + if (*word & 1) { + *word &= (eword_t)(~1); + } else { + *word |= (eword_t)1; + } +} + +static inline void rlw_set_running_len(eword_t *word, eword_t l) +{ + *word |= RLW_LARGEST_RUNNING_COUNT_SHIFT; + *word &= (l << 1) | (~RLW_LARGEST_RUNNING_COUNT_SHIFT); +} + +static inline eword_t rlw_get_running_len(const eword_t *word) +{ + return (*word >> 1) & RLW_LARGEST_RUNNING_COUNT; +} + +static inline eword_t rlw_get_literal_words(const eword_t *word) +{ + return *word >> (1 + RLW_RUNNING_BITS); +} + +static inline void rlw_set_literal_words(eword_t *word, eword_t l) +{ + *word |= ~RLW_RUNNING_LEN_PLUS_BIT; + *word &= (l << (RLW_RUNNING_BITS + 1)) | RLW_RUNNING_LEN_PLUS_BIT; +} + +static inline eword_t rlw_size(const eword_t *self) +{ + return rlw_get_running_len(self) + rlw_get_literal_words(self); +} + +struct rlw_iterator { + const eword_t *buffer; + size_t size; + size_t pointer; + size_t literal_word_start; + + struct { + const eword_t *word; + int literal_words; + int running_len; + int literal_word_offset; + int running_bit; + } rlw; +}; + +void rlwit_init(struct rlw_iterator *it, struct ewah_bitmap *bitmap); +void rlwit_discard_first_words(struct rlw_iterator *it, size_t x); +size_t rlwit_discharge( + struct rlw_iterator *it, struct ewah_bitmap *out, size_t max, int negate); +void rlwit_discharge_empty(struct rlw_iterator *it, struct ewah_bitmap *out); + +static inline size_t rlwit_word_size(struct rlw_iterator *it) +{ + return it->rlw.running_len + it->rlw.literal_words; +} + +static inline size_t rlwit_literal_words(struct rlw_iterator *it) +{ + return it->pointer - it->rlw.literal_words; +} + +#endif |