X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/829f74d29330aba341c679b697b511c8a18c172c..6082531abb3dca4b2fc213844200ce7b13fc05c5:/lib/lbitset.c diff --git a/lib/lbitset.c b/lib/lbitset.c index d279c5ec..9a6fc0ae 100644 --- a/lib/lbitset.c +++ b/lib/lbitset.c @@ -1,10 +1,10 @@ /* Functions to support link list bitsets. - Copyright (C) 2002 Free Software Foundation, Inc. + Copyright (C) 2002, 2003, 2004, 2006 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 + 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 + 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, @@ -13,19 +13,17 @@ 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. -*/ + along with this program. If not, see . */ -#ifdef HAVE_CONFIG_H -#include "config.h" -#endif +#include #include "lbitset.h" + #include "obstack.h" #include #include #include +#include /* This file implements linked-list bitsets. These bitsets can be of arbitrary length and are more efficient than arrays of bits for @@ -40,7 +38,10 @@ /* Number of words to use for each element. The larger the value the greater the size of the cache and the shorter the time to find a given bit but the more memory wasted for sparse bitsets and the longer the time - to search for set bits. */ + to search for set bits. + + The routines that dominate timing profiles are lbitset_elt_find + and lbitset_elt_link, especially when accessing the bits randomly. */ #define LBITSET_ELT_WORDS 2 @@ -50,7 +51,7 @@ typedef bitset_word lbitset_word; /* Number of bits stored in each element. */ #define LBITSET_ELT_BITS \ - ((unsigned) (LBITSET_ELT_WORDS * LBITSET_WORD_BITS)) + ((unsigned int) (LBITSET_ELT_WORDS * LBITSET_WORD_BITS)) /* Lbitset element. We use an array of bits for each element. These are linked together in a doubly-linked list. */ @@ -71,10 +72,10 @@ static lbitset_elt lbitset_zero_elts[3]; /* Elements of all zero bits. */ /* Obstack to allocate bitset elements from. */ static struct obstack lbitset_obstack; -static int lbitset_obstack_init = 0; +static bool lbitset_obstack_init = false; static lbitset_elt *lbitset_free_list; /* Free list of bitset elements. */ -extern void debug_lbitset PARAMS ((bitset)); +extern void debug_lbitset (bitset); #define LBITSET_CURRENT1(X) \ ((lbitset_elt *) (void *) ((char *) (X) - offsetof (lbitset_elt, words))) @@ -99,7 +100,7 @@ lbitset_elt_alloc (void) { if (!lbitset_obstack_init) { - lbitset_obstack_init = 1; + lbitset_obstack_init = true; /* Let particular systems override the size of a chunk. */ @@ -117,15 +118,13 @@ lbitset_elt_alloc (void) #define OBSTACK_CHUNK_FREE free #endif -#if !defined(__GNUC__) || (__GNUC__ < 2) +#if ! defined __GNUC__ || __GNUC__ < 2 #define __alignof__(type) 0 #endif obstack_specify_allocation (&lbitset_obstack, OBSTACK_CHUNK_SIZE, __alignof__ (lbitset_elt), - (void *(*)PARAMS ((long))) OBSTACK_CHUNK_ALLOC, - (void (*)PARAMS ((void *))) OBSTACK_CHUNK_FREE); } @@ -236,17 +235,17 @@ lbitset_prune (bitset bset, lbitset_elt *elt) } -/* Return nonzero if all bits in an element are zero. */ -static inline int +/* Are all bits in an element zero? */ +static inline bool lbitset_elt_zero_p (lbitset_elt *elt) { int i; for (i = 0; i < LBITSET_ELT_WORDS; i++) if (elt->words[i]) - return 0; + return false; - return 1; + return true; } @@ -361,6 +360,9 @@ lbitset_elt_find (bitset bset, bitset_windex windex, switch (mode) { + default: + abort (); + case LBITSET_FIND: return 0; @@ -374,9 +376,6 @@ lbitset_elt_find (bitset bset, bitset_windex windex, case LBITSET_SUBST: return &lbitset_zero_elts[0]; - - default: - abort (); } } @@ -412,8 +411,8 @@ lbitset_zero (bitset bset) } -/* Return 1 if DST == SRC. */ -static inline int +/* Is DST == SRC? */ +static inline bool lbitset_equal_p (bitset dst, bitset src) { lbitset_elt *selt; @@ -421,7 +420,7 @@ lbitset_equal_p (bitset dst, bitset src) int j; if (src == dst) - return 1; + return true; lbitset_weed (src); lbitset_weed (dst); @@ -429,11 +428,11 @@ lbitset_equal_p (bitset dst, bitset src) selt && delt; selt = selt->next, delt = delt->next) { if (selt->index != delt->index) - return 0; + return false; for (j = 0; j < LBITSET_ELT_WORDS; j++) if (delt->words[j] != selt->words[j]) - return 0; + return false; } return !selt && !delt; } @@ -480,13 +479,13 @@ lbitset_copy (bitset dst, bitset src) } -/* Copy bits from bitset SRC to bitset DST. Return non-zero if +/* Copy bits from bitset SRC to bitset DST. Return true if bitsets different. */ -static inline int +static inline bool lbitset_copy_cmp (bitset dst, bitset src) { if (src == dst) - return 0; + return false; if (!LBITSET_HEAD (dst)) { @@ -495,28 +494,22 @@ lbitset_copy_cmp (bitset dst, bitset src) } if (lbitset_equal_p (dst, src)) - return 0; + return false; lbitset_copy (dst, src); - return 1; + return true; } -/* Return size in bits of bitset SRC. */ static bitset_bindex -lbitset_size (bitset src) +lbitset_resize (bitset src, bitset_bindex size) { - lbitset_elt *elt; + BITSET_NBITS_ (src) = size; - elt = LBITSET_TAIL (src); - if (!elt) - return 0; - - /* Return current size of bitset in bits. */ - return (elt->index + LBITSET_ELT_WORDS) * BITSET_WORD_BITS; + /* Need to prune any excess bits. FIXME. */ + return size; } - /* Set bit BITNO in bitset DST. */ static void lbitset_set (bitset dst, bitset_bindex bitno) @@ -547,16 +540,15 @@ lbitset_reset (bitset dst, bitset_bindex bitno) /* Test bit BITNO in bitset SRC. */ -static int +static bool lbitset_test (bitset src, bitset_bindex bitno) { bitset_windex windex = bitno / BITSET_WORD_BITS; - if (!lbitset_elt_find (src, windex, LBITSET_FIND)) - return 0; - - return (src->b.cdata[windex - src->b.cindex] - >> (bitno % BITSET_WORD_BITS)) & 1; + return (lbitset_elt_find (src, windex, LBITSET_FIND) + && ((src->b.cdata[windex - src->b.cindex] + >> (bitno % BITSET_WORD_BITS)) + & 1)); } @@ -865,16 +857,54 @@ lbitset_list (bitset bset, bitset_bindex *list, } -static int +static bool lbitset_empty_p (bitset dst) { - lbitset_weed (dst); - if (LBITSET_HEAD (dst)) - return 0; + lbitset_elt *elt; + lbitset_elt *next; + + for (elt = LBITSET_HEAD (dst); elt; elt = next) + { + next = elt->next; + if (!lbitset_elt_zero_p (elt)) + return 0; + /* Weed as we go. */ + lbitset_elt_unlink (dst, elt); + } + return 1; } +/* Ensure that any unused bits within the last element are clear. */ +static inline void +lbitset_unused_clear (bitset dst) +{ + unsigned int last_bit; + bitset_bindex n_bits; + + n_bits = BITSET_SIZE_ (dst); + last_bit = n_bits % LBITSET_ELT_BITS; + + if (last_bit) + { + lbitset_elt *elt; + bitset_windex windex; + bitset_word *srcp; + + elt = LBITSET_TAIL (dst); + srcp = elt->words; + windex = n_bits / BITSET_WORD_BITS; + + srcp[windex - elt->index] &= ((bitset_word) 1 << last_bit) - 1; + windex++; + + for (; (windex - elt->index) < LBITSET_ELT_WORDS; windex++) + srcp[windex - elt->index] = 0; + } +} + + static void lbitset_ones (bitset dst) { @@ -886,18 +916,17 @@ lbitset_ones (bitset dst) bitset! It makes a sparse bitset become dense. An alternative is to have a flag that indicates that the bitset stores the complement of what it indicates. */ - elt = LBITSET_TAIL (dst); - /* Ignore empty set. */ - if (!elt) - return; - windex = elt->index; + windex = (BITSET_SIZE_ (dst) + BITSET_WORD_BITS - 1) / BITSET_WORD_BITS; + for (i = 0; i < windex; i += LBITSET_ELT_WORDS) { /* Create new elements if they cannot be found. */ elt = lbitset_elt_find (dst, i, LBITSET_CREATE); memset (elt->words, -1, sizeof (elt->words)); } + + lbitset_unused_clear (dst); } @@ -914,11 +943,9 @@ lbitset_not (bitset dst, bitset src) /* This is another unfriendly operation for a linked list bitset! */ elt = LBITSET_TAIL (dst); - /* Ignore empty set. */ - if (!elt) - return; - windex = elt->index; + windex = (BITSET_SIZE_ (dst) + BITSET_WORD_BITS - 1) / BITSET_WORD_BITS; + for (i = 0; i < windex; i += LBITSET_ELT_WORDS) { /* Create new elements for dst if they cannot be found @@ -929,13 +956,14 @@ lbitset_not (bitset dst, bitset src) for (j = 0; j < LBITSET_ELT_WORDS; j++) delt->words[j] = ~selt->words[j]; } + lbitset_unused_clear (dst); lbitset_weed (dst); return; } -/* Return 1 if DST == DST | SRC. */ -static int +/* Is DST == DST | SRC? */ +static bool lbitset_subset_p (bitset dst, bitset src) { lbitset_elt *selt; @@ -965,14 +993,14 @@ lbitset_subset_p (bitset dst, bitset src) for (j = 0; j < LBITSET_ELT_WORDS; j++) if (delt->words[j] != (selt->words[j] | delt->words[j])) - return 0; + return false; } - return 1; + return true; } -/* Return 1 if DST & SRC == 0. */ -static int +/* Is DST & SRC == 0? */ +static bool lbitset_disjoint_p (bitset dst, bitset src) { lbitset_elt *selt; @@ -1001,13 +1029,13 @@ lbitset_disjoint_p (bitset dst, bitset src) for (j = 0; j < LBITSET_ELT_WORDS; j++) if (selt->words[j] & delt->words[j]) - return 0; + return false; } - return 1; + return true; } -static int +static bool lbitset_op3_cmp (bitset dst, bitset src1, bitset src2, enum bitset_ops op) { lbitset_elt *selt1 = LBITSET_HEAD (src1); @@ -1022,7 +1050,7 @@ lbitset_op3_cmp (bitset dst, bitset src1, bitset src2, enum bitset_ops op) bitset_word *srcp1; bitset_word *srcp2; bitset_word *dstp; - int changed = 0; + bool changed = false; unsigned int i; LBITSET_HEAD (dst) = 0; @@ -1066,7 +1094,7 @@ lbitset_op3_cmp (bitset dst, bitset src1, bitset src2, enum bitset_ops op) elements that we've skipped. */ while (delt && delt->index < windex) { - changed = 1; + changed = true; dtmp = delt; delt = delt->next; lbitset_elt_free (dtmp); @@ -1086,6 +1114,9 @@ lbitset_op3_cmp (bitset dst, bitset src1, bitset src2, enum bitset_ops op) dstp = dtmp->words; switch (op) { + default: + abort (); + case BITSET_OP_OR: for (i = 0; i < LBITSET_ELT_WORDS; i++, dstp++) { @@ -1093,7 +1124,7 @@ lbitset_op3_cmp (bitset dst, bitset src1, bitset src2, enum bitset_ops op) if (*dstp != tmp) { - changed = 1; + changed = true; *dstp = tmp; } } @@ -1106,7 +1137,7 @@ lbitset_op3_cmp (bitset dst, bitset src1, bitset src2, enum bitset_ops op) if (*dstp != tmp) { - changed = 1; + changed = true; *dstp = tmp; } } @@ -1119,7 +1150,7 @@ lbitset_op3_cmp (bitset dst, bitset src1, bitset src2, enum bitset_ops op) if (*dstp != tmp) { - changed = 1; + changed = true; *dstp = tmp; } } @@ -1132,14 +1163,11 @@ lbitset_op3_cmp (bitset dst, bitset src1, bitset src2, enum bitset_ops op) if (*dstp != tmp) { - changed = 1; + changed = true; *dstp = tmp; } } break; - - default: - abort (); } if (!lbitset_elt_zero_p (dtmp)) @@ -1157,7 +1185,7 @@ lbitset_op3_cmp (bitset dst, bitset src1, bitset src2, enum bitset_ops op) /* If we have elements of DST left over, free them all. */ if (delt) { - changed = 1; + changed = true; lbitset_prune (dst, delt); } @@ -1165,12 +1193,12 @@ lbitset_op3_cmp (bitset dst, bitset src1, bitset src2, enum bitset_ops op) } -static int +static bool lbitset_and_cmp (bitset dst, bitset src1, bitset src2) { lbitset_elt *selt1 = LBITSET_HEAD (src1); lbitset_elt *selt2 = LBITSET_HEAD (src2); - int changed; + bool changed; if (!selt2) { @@ -1197,12 +1225,12 @@ lbitset_and (bitset dst, bitset src1, bitset src2) } -static int +static bool lbitset_andn_cmp (bitset dst, bitset src1, bitset src2) { lbitset_elt *selt1 = LBITSET_HEAD (src1); lbitset_elt *selt2 = LBITSET_HEAD (src2); - int changed; + bool changed; if (!selt2) { @@ -1226,7 +1254,7 @@ lbitset_andn (bitset dst, bitset src1, bitset src2) } -static int +static bool lbitset_or_cmp (bitset dst, bitset src1, bitset src2) { lbitset_elt *selt1 = LBITSET_HEAD (src1); @@ -1251,7 +1279,7 @@ lbitset_or (bitset dst, bitset src1, bitset src2) } -static int +static bool lbitset_xor_cmp (bitset dst, bitset src1, bitset src2) { lbitset_elt *selt1 = LBITSET_HEAD (src1); @@ -1283,7 +1311,8 @@ struct bitset_vtable lbitset_vtable = { lbitset_reset, bitset_toggle_, lbitset_test, - lbitset_size, + lbitset_resize, + bitset_size_, bitset_count_, lbitset_empty_p, lbitset_ones, @@ -1326,6 +1355,7 @@ lbitset_bytes (bitset_bindex n_bits ATTRIBUTE_UNUSED) bitset lbitset_init (bitset bset, bitset_bindex n_bits ATTRIBUTE_UNUSED) { + BITSET_NBITS_ (bset) = n_bits; bset->b.vtable = &lbitset_vtable; return bset; } @@ -1337,7 +1367,7 @@ lbitset_release_memory (void) lbitset_free_list = 0; if (lbitset_obstack_init) { - lbitset_obstack_init = 0; + lbitset_obstack_init = false; obstack_free (&lbitset_obstack, NULL); } } @@ -1355,7 +1385,7 @@ debug_lbitset (bitset bset) for (elt = LBITSET_HEAD (bset); elt; elt = elt->next) { - fprintf (stderr, "Elt %lu\n", (unsigned long) elt->index); + fprintf (stderr, "Elt %lu\n", (unsigned long int) elt->index); for (i = 0; i < LBITSET_ELT_WORDS; i++) { unsigned int j;