/* Base bitset stuff. Copyright (C) 2002-2004, 2006, 2009-2015, 2018-2021 Free Software Foundation, Inc. Contributed by Michael Hayes (m.hayes@elec.canterbury.ac.nz). 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 3 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, see . */ #ifndef _BITSET_BASE_H #define _BITSET_BASE_H #include #include #include #include /* because Gnulib's may '#define free ...' */ #ifndef _MSC_VER #include /* ffsl */ #else #include #endif #include "attribute.h" #include "integer_length.h" #include "xalloc.h" /* Currently we support five flavours of bitsets: BITSET_ARRAY: Array of bits (fixed size, fast for dense bitsets). Memory for bit array and bitset structure allocated contiguously. BITSET_LIST: Linked list of arrays of bits (variable size, least storage for large very sparse sets). BITSET_TABLE: Expandable table of pointers to arrays of bits (variable size, less storage for large sparse sets). Faster than BITSET_LIST for random access. BITSET_VECTOR: Variable array of bits (variable size, fast for dense bitsets). BITSET_STATS: Wrapper bitset for internal use only. Used for gathering statistics and/or better run-time checking. */ enum bitset_type {BITSET_ARRAY, BITSET_LIST, BITSET_TABLE, BITSET_VECTOR, BITSET_TYPE_NUM, BITSET_STATS}; #define BITSET_TYPE_NAMES {"abitset", "lbitset", "tbitset", "vbitset"} extern const char * const bitset_type_names[]; /* Data type used to store a word of bits. */ typedef unsigned long bitset_word; #define BITSET_WORD_BITS ((unsigned) (CHAR_BIT * sizeof (bitset_word))) /* Bit index. In theory we might need a type wider than size_t, but in practice we lose at most a factor of CHAR_BIT by going with size_t, and that is good enough. If this type is changed to be wider than size_t, the code needs to be modified to check for overflow when converting bit counts to byte or word counts. The bit and word index types must be unsigned. */ typedef size_t bitset_bindex; /* Word index. */ typedef size_t bitset_windex; /* Maximum values for commonly-used unsigned types. BITSET_SIZE_MAX always equals SIZE_MAX, but some older systems lack SIZE_MAX. */ #define BITSET_BINDEX_MAX ((bitset_bindex) -1) /* Limit max word index to the maximum value of a signed integer to simplify cache disabling. */ #define BITSET_WINDEX_MAX (((bitset_windex) -1) >> 1) #define BITSET_SIZE_MAX ((size_t) -1) #define BITSET_MSB ((bitset_word) 1 << (BITSET_WORD_BITS - 1)) #define BITSET_LIST_SIZE 1024 enum bitset_ops {BITSET_OP_ZERO, BITSET_OP_ONES, BITSET_OP_COPY, BITSET_OP_NOT, BITSET_OP_EMPTY_P, BITSET_OP_EQUAL_P, BITSET_OP_SUBSET_P, BITSET_OP_DISJOINT_P, BITSET_OP_AND, BITSET_OP_OR, BITSET_OP_XOR, BITSET_OP_ANDN, BITSET_OP_OR_AND, BITSET_OP_AND_OR, BITSET_OP_ANDN_OR}; struct bbitset_struct { const struct bitset_vtable *vtable; bitset_windex cindex; /* Cache word index. */ bitset_windex csize; /* Cache size in words. */ bitset_word *cdata; /* Cache data pointer. */ bitset_bindex n_bits; /* Number of bits. */ /* Perhaps we could sacrifice another word to indicate that the bitset is known to be zero, that a bit has been set in the cache, and that a bit has been cleared in the cache. This would speed up some of the searches but slightly slow down bit set/reset operations of cached bits. */ }; typedef union bitset_union *bitset; /* Private accessor macros to bitset structure. */ #define BITSET_VTABLE_(SRC) (SRC)->b.vtable #define BITSET_CINDEX_(SRC) (SRC)->b.cindex #define BITSET_CDATA_(SRC) (SRC)->b.cdata #define BITSET_CSIZE_(SRC) (SRC)->b.csize #define BITSET_NBITS_(SRC) (SRC)->b.n_bits /* The contents of this structure should be considered private. */ struct bitset_vtable { void (*set) (bitset, bitset_bindex); void (*reset) (bitset, bitset_bindex); bool (*toggle) (bitset, bitset_bindex); bool (*test) (bitset, bitset_bindex); bitset_bindex (*resize) (bitset, bitset_bindex); bitset_bindex (*size) (bitset); bitset_bindex (*count) (bitset); bool (*empty_p) (bitset); void (*ones) (bitset); void (*zero) (bitset); void (*copy) (bitset, bitset); bool (*disjoint_p) (bitset, bitset); bool (*equal_p) (bitset, bitset); void (*not_) (bitset, bitset); bool (*subset_p) (bitset, bitset); void (*and_) (bitset, bitset, bitset); bool (*and_cmp) (bitset, bitset, bitset); void (*andn) (bitset, bitset, bitset); bool (*andn_cmp) (bitset, bitset, bitset); void (*or_) (bitset, bitset, bitset); bool (*or_cmp) (bitset, bitset, bitset); void (*xor_) (bitset, bitset, bitset); bool (*xor_cmp) (bitset, bitset, bitset); void (*and_or) (bitset, bitset, bitset, bitset); bool (*and_or_cmp) (bitset, bitset, bitset, bitset); void (*andn_or) (bitset, bitset, bitset, bitset); bool (*andn_or_cmp) (bitset, bitset, bitset, bitset); void (*or_and) (bitset, bitset, bitset, bitset); bool (*or_and_cmp) (bitset, bitset, bitset, bitset); bitset_bindex (*list) (bitset, bitset_bindex *, bitset_bindex, bitset_bindex *); bitset_bindex (*list_reverse) (bitset, bitset_bindex *, bitset_bindex, bitset_bindex *); void (*free) (bitset); enum bitset_type type; }; #define BITSET_COMPATIBLE_(BSET1, BSET2) \ ((BSET1)->b.vtable == (BSET2)->b.vtable) #define BITSET_CHECK2_(DST, SRC) \ if (!BITSET_COMPATIBLE_ (DST, SRC)) abort (); #define BITSET_CHECK3_(DST, SRC1, SRC2) \ if (!BITSET_COMPATIBLE_ (DST, SRC1) \ || !BITSET_COMPATIBLE_ (DST, SRC2)) abort (); #define BITSET_CHECK4_(DST, SRC1, SRC2, SRC3) \ if (!BITSET_COMPATIBLE_ (DST, SRC1) || !BITSET_COMPATIBLE_ (DST, SRC2) \ || !BITSET_COMPATIBLE_ (DST, SRC3)) abort (); /* Redefine number of bits in bitset DST. */ #define BITSET_RESIZE_(DST, SIZE) (DST)->b.vtable->resize (DST, SIZE) /* Return size in bits of bitset SRC. */ #define BITSET_SIZE_(SRC) (SRC)->b.vtable->size (SRC) /* Return number of bits set in bitset SRC. */ #define BITSET_COUNT_(SRC) (SRC)->b.vtable->count (SRC) /* Return type of bitset SRC. */ #define BITSET_TYPE_(DST) (DST)->b.vtable->type /* Set bit BITNO in bitset DST. */ #define BITSET_SET_(DST, BITNO) (DST)->b.vtable->set (DST, BITNO) /* Reset bit BITNO in bitset DST. */ #define BITSET_RESET_(DST, BITNO) (DST)->b.vtable->reset (DST, BITNO) /* Toggle bit BITNO in bitset DST. */ #define BITSET_TOGGLE_(DST, BITNO) (DST)->b.vtable->toggle (DST, BITNO) /* Return non-zero if bit BITNO in bitset SRC is set. */ #define BITSET_TEST_(SRC, BITNO) (SRC)->b.vtable->test (SRC, BITNO) /* Free bitset SRC. */ #define BITSET_FREE_(SRC)\ ((SRC)->b.vtable->free ? (SRC)->b.vtable->free (SRC) :(void)0) /* Return SRC == 0. */ #define BITSET_EMPTY_P_(SRC) (SRC)->b.vtable->empty_p (SRC) /* DST = ~0. */ #define BITSET_ONES_(DST) (DST)->b.vtable->ones (DST) /* DST = 0. */ #define BITSET_ZERO_(DST) (DST)->b.vtable->zero (DST) /* DST = SRC. */ #define BITSET_COPY_(DST, SRC) (SRC)->b.vtable->copy (DST, SRC) /* Return DST & SRC == 0. */ #define BITSET_DISJOINT_P_(DST, SRC) (SRC)->b.vtable->disjoint_p (DST, SRC) /* Return DST == SRC. */ #define BITSET_EQUAL_P_(DST, SRC) (SRC)->b.vtable->equal_p (DST, SRC) /* DST = ~SRC. */ #define BITSET_NOT_(DST, SRC) (SRC)->b.vtable->not_ (DST, SRC) /* Return DST == DST | SRC. */ #define BITSET_SUBSET_P_(DST, SRC) (SRC)->b.vtable->subset_p (DST, SRC) /* DST = SRC1 & SRC2. */ #define BITSET_AND_(DST, SRC1, SRC2) (SRC1)->b.vtable->and_ (DST, SRC1, SRC2) #define BITSET_AND_CMP_(DST, SRC1, SRC2) (SRC1)->b.vtable->and_cmp (DST, SRC1, SRC2) /* DST = SRC1 & ~SRC2. */ #define BITSET_ANDN_(DST, SRC1, SRC2) (SRC1)->b.vtable->andn (DST, SRC1, SRC2) #define BITSET_ANDN_CMP_(DST, SRC1, SRC2) (SRC1)->b.vtable->andn_cmp (DST, SRC1, SRC2) /* DST = SRC1 | SRC2. */ #define BITSET_OR_(DST, SRC1, SRC2) (SRC1)->b.vtable->or_ (DST, SRC1, SRC2) #define BITSET_OR_CMP_(DST, SRC1, SRC2) (SRC1)->b.vtable->or_cmp (DST, SRC1, SRC2) /* DST = SRC1 ^ SRC2. */ #define BITSET_XOR_(DST, SRC1, SRC2) (SRC1)->b.vtable->xor_ (DST, SRC1, SRC2) #define BITSET_XOR_CMP_(DST, SRC1, SRC2) (SRC1)->b.vtable->xor_cmp (DST, SRC1, SRC2) /* DST = (SRC1 & SRC2) | SRC3. Return non-zero if DST != (SRC1 & SRC2) | SRC3. */ #define BITSET_AND_OR_(DST, SRC1, SRC2, SRC3) \ (SRC1)->b.vtable->and_or (DST, SRC1, SRC2, SRC3) #define BITSET_AND_OR_CMP_(DST, SRC1, SRC2, SRC3) \ (SRC1)->b.vtable->and_or_cmp (DST, SRC1, SRC2, SRC3) /* DST = (SRC1 & ~SRC2) | SRC3. Return non-zero if DST != (SRC1 & ~SRC2) | SRC3. */ #define BITSET_ANDN_OR_(DST, SRC1, SRC2, SRC3) \ (SRC1)->b.vtable->andn_or (DST, SRC1, SRC2, SRC3) #define BITSET_ANDN_OR_CMP_(DST, SRC1, SRC2, SRC3) \ (SRC1)->b.vtable->andn_or_cmp (DST, SRC1, SRC2, SRC3) /* DST = (SRC1 | SRC2) & SRC3. Return non-zero if DST != (SRC1 | SRC2) & SRC3. */ #define BITSET_OR_AND_(DST, SRC1, SRC2, SRC3) \ (SRC1)->b.vtable->or_and (DST, SRC1, SRC2, SRC3) #define BITSET_OR_AND_CMP_(DST, SRC1, SRC2, SRC3) \ (SRC1)->b.vtable->or_and_cmp (DST, SRC1, SRC2, SRC3) /* Find list of up to NUM bits set in BSET starting from and including *NEXT. Return with actual number of bits found and with *NEXT indicating where search stopped. */ #define BITSET_LIST_(BSET, LIST, NUM, NEXT) \ (BSET)->b.vtable->list (BSET, LIST, NUM, NEXT) /* Find reverse list of up to NUM bits set in BSET starting from and including NEXT. Return with actual number of bits found and with *NEXT indicating where search stopped. */ #define BITSET_LIST_REVERSE_(BSET, LIST, NUM, NEXT) \ (BSET)->b.vtable->list_reverse (BSET, LIST, NUM, NEXT) /* Iterate left to right over each set bit of WORD. Each iteration sets POS to the 0-based index of the next set bit in WORD. Repeatedly resets bits in WORD in place until it's null. */ #define BITSET_FOR_EACH_BIT(Pos, Word) \ for (int Pos = bitset_ffs_ (Word); \ 0 <= Pos; \ Word ^= 1UL << Pos, Pos = bitset_ffs_ (Word)) /* Iterate right to left over each set bit of WORD. Each iteration sets POS to the 0-based index of the next set bit in WORD. Repeatedly resets bits in WORD in place until it's null. */ #define BITSET_FOR_EACH_BIT_REVERSE(Pos, Word) \ for (int Pos = bitset_fls_ (Word); \ 0 <= Pos; \ Word ^= 1UL << Pos, Pos = bitset_fls_ (Word)) /* Private functions for bitset implementations. */ bool bitset_toggle_ (bitset, bitset_bindex); bitset_bindex bitset_count_ (bitset); bitset_bindex bitset_size_ (bitset); bool bitset_copy_ (bitset, bitset); void bitset_and_or_ (bitset, bitset, bitset, bitset); bool bitset_and_or_cmp_ (bitset, bitset, bitset, bitset); void bitset_andn_or_ (bitset, bitset, bitset, bitset); bool bitset_andn_or_cmp_ (bitset, bitset, bitset, bitset); void bitset_or_and_ (bitset, bitset, bitset, bitset); bool bitset_or_and_cmp_ (bitset, bitset, bitset, bitset); /* First set bit in WORD. Indexes start at 0, return -1 if WORD is null. */ static inline int bitset_ffs_ (bitset_word word) { #ifndef _MSC_VER return ffsl ((long) word) - 1; #else unsigned long bit, val = word; if (_BitScanForward (&bit, val)) return bit; else return -1; #endif } /* Last set bit in WORD. Indexes start at 0, return -1 if WORD is null. */ static inline int bitset_fls_ (bitset_word word) { return integer_length_l (word) - 1; } #endif /* _BBITSET_H */