X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/8a731ca8296e54a6fb31eb42cead791baf6810e7..d0ee410565c9d7bc876af42583ee092568f44fa8:/src/state.c?ds=sidebyside diff --git a/src/state.c b/src/state.c index dd8ec750..aa392aec 100644 --- a/src/state.c +++ b/src/state.c @@ -1,29 +1,32 @@ -/* Type definitions for nondeterministic finite state machine for bison, - Copyright (C) 2001, 2002 Free Software Foundation, Inc. +/* Type definitions for nondeterministic finite state machine for Bison. + + Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007 Free Software + Foundation, Inc. This file is part of Bison, the GNU Compiler Compiler. - Bison 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, or (at your option) - any later version. + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. - Bison is distributed in the hope that it will be useful, + 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 Bison; see the file COPYING. 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 . */ +#include #include "system.h" -#include "hash.h" + +#include + #include "complain.h" #include "gram.h" #include "state.h" +#include "print-xml.h" /*-------------------. @@ -31,24 +34,37 @@ `-------------------*/ -/*---------------------------------------. -| Create a new array of N shifts/gotos. | -`---------------------------------------*/ - -#define SHIFTS_ALLOC(Nshifts) \ - (shifts_t *) xcalloc ((unsigned) (sizeof (shifts_t) \ - + (Nshifts - 1) * sizeof (state_number_t)), 1) +/*-----------------------------------------. +| Create a new array of NUM shifts/gotos. | +`-----------------------------------------*/ -static shifts_t * -shifts_new (int nshifts, state_number_t *shifts) +static transitions * +transitions_new (int num, state **the_states) { - shifts_t *res = SHIFTS_ALLOC (nshifts); - res->nshifts = nshifts; - memcpy (res->shifts, shifts, nshifts * sizeof (shifts[0])); + size_t states_size = num * sizeof *the_states; + transitions *res = xmalloc (offsetof (transitions, states) + states_size); + res->num = num; + memcpy (res->states, the_states, states_size); return res; } +/*-------------------------------------------------------. +| Return the state such that SHIFTS contain a shift/goto | +| to it on SYM. Abort if none found. | +`-------------------------------------------------------*/ + +state * +transitions_to (transitions *shifts, symbol_number sym) +{ + int j; + for (j = 0; ; j++) + { + aver (j < shifts->num); + if (TRANSITION_SYMBOL (shifts, j) == sym) + return shifts->states[j]; + } +} /*--------------------. @@ -56,29 +72,17 @@ shifts_new (int nshifts, state_number_t *shifts) `--------------------*/ -/*-------------------------------. -| Create a new array of N errs. | -`-------------------------------*/ - -#define ERRS_ALLOC(Nerrs) \ - (errs_t *) xcalloc ((unsigned) (sizeof (errs_t) \ - + (Nerrs - 1) * sizeof (short)), 1) - +/*---------------------------------. +| Create a new array of NUM errs. | +`---------------------------------*/ -errs_t * -errs_new (int n) +errs * +errs_new (int num, symbol **tokens) { - errs_t *res = ERRS_ALLOC (n); - res->nerrs = n; - return res; -} - - -errs_t * -errs_dup (errs_t *src) -{ - errs_t *res = errs_new (src->nerrs); - memcpy (res->errs, src->errs, src->nerrs * sizeof (src->errs[0])); + size_t symbols_size = num * sizeof *tokens; + errs *res = xmalloc (offsetof (errs, symbols) + symbols_size); + res->num = num; + memcpy (res->symbols, tokens, symbols_size); return res; } @@ -90,20 +94,18 @@ errs_dup (errs_t *src) `-------------*/ -/*-------------------------------------. -| Create a new array of N reductions. | -`-------------------------------------*/ - -#define REDUCTIONS_ALLOC(Nreductions) \ - (reductions_t *) xcalloc ((unsigned) (sizeof (reductions_t) \ - + (Nreductions - 1) * sizeof (short)), 1) +/*---------------------------------------. +| Create a new array of NUM reductions. | +`---------------------------------------*/ -static reductions_t * -reductions_new (int nreductions, short *reductions) +static reductions * +reductions_new (int num, rule **reds) { - reductions_t *res = REDUCTIONS_ALLOC (nreductions); - res->nreds = nreductions; - memcpy (res->rules, reductions, nreductions * sizeof (reductions[0])); + size_t rules_size = num * sizeof *reds; + reductions *res = xmalloc (offsetof (reductions, rules) + rules_size); + res->num = num; + res->lookahead_tokens = NULL; + memcpy (res->rules, reds, rules_size); return res; } @@ -114,100 +116,164 @@ reductions_new (int nreductions, short *reductions) `---------*/ -state_number_t nstates = 0; +state_number nstates = 0; /* FINAL_STATE is properly set by new_state when it recognizes its - accessing symbol: EOF. */ -state_t *final_state = NULL; + accessing symbol: $end. */ +state *final_state = NULL; -#define STATE_ALLOC(Nitems) \ - (state_t *) xcalloc ((unsigned) (sizeof (state_t) \ - + (Nitems - 1) * sizeof (item_number_t)), 1) -/*------------------------------------------------------------. -| Create a new state with ACCESSING_SYMBOL, for those items. | -`------------------------------------------------------------*/ +/*------------------------------------------------------------------. +| Create a new state with ACCESSING_SYMBOL, for those items. Store | +| it in the state hash table. | +`------------------------------------------------------------------*/ -state_t * -state_new (symbol_number_t accessing_symbol, - size_t core_size, item_number_t *core) +state * +state_new (symbol_number accessing_symbol, + size_t nitems, item_number *core) { - state_t *res; + state *res; + size_t items_size = nitems * sizeof *core; - if (nstates >= STATE_NUMBER_MAX) - fatal (_("too many states (max %d)"), STATE_NUMBER_MAX); + aver (nstates < STATE_NUMBER_MAXIMUM); - res = STATE_ALLOC (core_size); + res = xmalloc (offsetof (state, items) + items_size); + res->number = nstates++; res->accessing_symbol = accessing_symbol; - res->number = nstates; - ++nstates; + res->transitions = NULL; + res->reductions = NULL; + res->errs = NULL; + res->consistent = 0; res->solved_conflicts = NULL; + res->solved_conflicts_xml = NULL; + + res->nitems = nitems; + memcpy (res->items, core, items_size); - res->nitems = core_size; - memcpy (res->items, core, core_size * sizeof (core[0])); + state_hash_insert (res); return res; } +/*---------. +| Free S. | +`---------*/ + +static void +state_free (state *s) +{ + free (s->transitions); + free (s->reductions); + free (s->errs); + free (s); +} + + +/*---------------------------. +| Set the transitions of S. | +`---------------------------*/ + +void +state_transitions_set (state *s, int num, state **trans) +{ + aver (!s->transitions); + s->transitions = transitions_new (num, trans); +} + + /*--------------------------. -| Set the shifts of STATE. | +| Set the reductions of S. | `--------------------------*/ void -state_shifts_set (state_t *state, int nshifts, state_number_t *shifts) +state_reductions_set (state *s, int num, rule **reds) { - state->shifts = shifts_new (nshifts, shifts); + aver (!s->reductions); + s->reductions = reductions_new (num, reds); } -/*------------------------------. -| Set the reductions of STATE. | -`------------------------------*/ +int +state_reduction_find (state *s, rule *r) +{ + int i; + reductions *reds = s->reductions; + for (i = 0; i < reds->num; ++i) + if (reds->rules[i] == r) + return i; + return -1; +} + + +/*--------------------. +| Set the errs of S. | +`--------------------*/ void -state_reductions_set (state_t *state, int nreductions, short *reductions) +state_errs_set (state *s, int num, symbol **tokens) { - state->reductions = reductions_new (nreductions, reductions); + aver (!s->errs); + s->errs = errs_new (num, tokens); } -/*--------------------------------------------------------------. -| Print on OUT all the lookaheads such that this STATE wants to | -| reduce this RULE. | -`--------------------------------------------------------------*/ +/*--------------------------------------------------. +| Print on OUT all the lookahead tokens such that S | +| wants to reduce R. | +`--------------------------------------------------*/ void -state_rule_lookaheads_print (state_t *state, rule_t *rule, FILE *out) +state_rule_lookahead_tokens_print (state *s, rule *r, FILE *out) { - int j, k; - int nlookaheads = 0; - /* Count the number of lookaheads corresponding to this rule. */ - for (j = 0; j < state->nlookaheads; ++j) - for (k = 0; k < ntokens; ++k) - if (bitset_test (state->lookaheads[j], k) - && state->lookaheads_rule[j]->number == rule->number) - nlookaheads++; + /* Find the reduction we are handling. */ + reductions *reds = s->reductions; + int red = state_reduction_find (s, r); /* Print them if there are. */ - if (nlookaheads) + if (reds->lookahead_tokens && red != -1) { + bitset_iterator biter; + int k; + char const *sep = ""; fprintf (out, " ["); - for (j = 0; j < state->nlookaheads; ++j) - for (k = 0; k < ntokens; ++k) - if (bitset_test (state->lookaheads[j], k) - && state->lookaheads_rule[j]->number == rule->number) - fprintf (out, "%s%s", - symbol_tag_get (symbols[k]), - --nlookaheads ? ", " : ""); + BITSET_FOR_EACH (biter, reds->lookahead_tokens[red], k, 0) + { + fprintf (out, "%s%s", sep, symbols[k]->tag); + sep = ", "; + } fprintf (out, "]"); } } +void +state_rule_lookahead_tokens_print_xml (state *s, rule *r, + FILE *out, int level) +{ + /* Find the reduction we are handling. */ + reductions *reds = s->reductions; + int red = state_reduction_find (s, r); -/*----------------------. + /* Print them if there are. */ + if (reds->lookahead_tokens && red != -1) + { + bitset_iterator biter; + int k; + xml_puts (out, level, ""); + BITSET_FOR_EACH (biter, reds->lookahead_tokens[red], k, 0) + { + xml_printf (out, level + 1, "%s", + symbol_class_get_string (symbols[k]), + xml_escape (symbols[k]->tag)); + } + xml_puts (out, level, ""); + } +} + + +/*---------------------. | A state hash table. | -`----------------------*/ +`---------------------*/ /* Initial capacity of states hash table. */ #define HT_INITIAL_CAPACITY 257 @@ -215,32 +281,44 @@ state_rule_lookaheads_print (state_t *state, rule_t *rule, FILE *out) static struct hash_table *state_table = NULL; /* Two states are equal if they have the same core items. */ -static bool -state_compare (const state_t *s1, const state_t *s2) +static inline bool +state_compare (state const *s1, state const *s2) { - int i; + size_t i; if (s1->nitems != s2->nitems) - return FALSE; + return false; for (i = 0; i < s1->nitems; ++i) if (s1->items[i] != s2->items[i]) - return FALSE; + return false; + + return true; +} - return TRUE; +static bool +state_comparator (void const *s1, void const *s2) +{ + return state_compare (s1, s2); } -static unsigned int -state_hash (const state_t *state, unsigned int tablesize) +static inline size_t +state_hash (state const *s, size_t tablesize) { /* Add up the state's item numbers to get a hash key. */ - int key = 0; - int i; - for (i = 0; i < state->nitems; ++i) - key += state->items[i]; + size_t key = 0; + size_t i; + for (i = 0; i < s->nitems; ++i) + key += s->items[i]; return key % tablesize; } +static size_t +state_hasher (void const *s, size_t tablesize) +{ + return state_hash (s, tablesize); +} + /*-------------------------------. | Create the states hash table. | @@ -251,9 +329,9 @@ state_hash_new (void) { state_table = hash_initialize (HT_INITIAL_CAPACITY, NULL, - (Hash_hasher) state_hash, - (Hash_comparator) state_compare, - (Hash_data_freer) NULL); + state_hasher, + state_comparator, + NULL); } @@ -268,14 +346,14 @@ state_hash_free (void) } -/*---------------------------------------. -| Insert STATE in the state hash table. | -`---------------------------------------*/ +/*-----------------------------------. +| Insert S in the state hash table. | +`-----------------------------------*/ void -state_hash_insert (state_t *state) +state_hash_insert (state *s) { - hash_insert (state_table, state); + hash_insert (state_table, s); } @@ -284,21 +362,68 @@ state_hash_insert (state_t *state) | not exist yet, return NULL. | `------------------------------------------------------------------*/ -state_t * -state_hash_lookup (size_t core_size, item_number_t *core) +state * +state_hash_lookup (size_t nitems, item_number *core) { - state_t *probe = STATE_ALLOC (core_size); - state_t *entry; + size_t items_size = nitems * sizeof *core; + state *probe = xmalloc (offsetof (state, items) + items_size); + state *entry; - probe->nitems = core_size; - memcpy (probe->items, core, core_size * sizeof (core[0])); + probe->nitems = nitems; + memcpy (probe->items, core, items_size); entry = hash_lookup (state_table, probe); free (probe); return entry; } + +/*--------------------------------------------------------. +| Record S and all states reachable from S in REACHABLE. | +`--------------------------------------------------------*/ + +static void +state_record_reachable_states (state *s, bitset reachable) +{ + if (bitset_test (reachable, s->number)) + return; + bitset_set (reachable, s->number); + { + int i; + for (i = 0; i < s->transitions->num; ++i) + if (!TRANSITION_IS_DISABLED (s->transitions, i)) + state_record_reachable_states (s->transitions->states[i], reachable); + } +} + +void +state_remove_unreachable_states (state_number old_to_new[]) +{ + state_number nstates_reachable = 0; + bitset reachable = bitset_create (nstates, BITSET_FIXED); + state_record_reachable_states (states[0], reachable); + { + state_number i; + for (i = 0; i < nstates; ++i) + { + if (bitset_test (reachable, states[i]->number)) + { + states[nstates_reachable] = states[i]; + states[nstates_reachable]->number = nstates_reachable; + old_to_new[i] = nstates_reachable++; + } + else + { + state_free (states[i]); + old_to_new[i] = nstates; + } + } + } + nstates = nstates_reachable; + bitset_free (reachable); +} + /* All the decorated states, indexed by the state number. */ -state_t **states = NULL; +state **states = NULL; /*----------------------. @@ -308,14 +433,8 @@ state_t **states = NULL; void states_free (void) { - state_number_t i; - + state_number i; for (i = 0; i < nstates; ++i) - { - free (states[i]->shifts); - XFREE (states[i]->reductions); - free (states[i]->errs); - free (states[i]); - } - XFREE (states); + state_free (states[i]); + free (states); }