X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/640748eecf67130c80b5fd5f5cca19630eddf2b3..75ae8299840bbd854fa2474d38402bbb933c6511:/src/state.c diff --git a/src/state.c b/src/state.c index 77307126..c11b10f7 100644 --- a/src/state.c +++ b/src/state.c @@ -1,249 +1,304 @@ -/* Type definitions for nondeterministic finite state machine for bison, - Copyright (C) 2001, 2002 Free Software Foundation, Inc. +/* Type definitions for the finite state machine for Bison. + + Copyright (C) 2001-2007, 2009-2013 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 <http://www.gnu.org/licenses/>. */ +#include <config.h> #include "system.h" -#include "hash.h" + +#include <hash.h> + #include "complain.h" #include "gram.h" #include "state.h" +#include "print-xml.h" - /*-------------------. - | Shifts and Gotos. | - `-------------------*/ + /*-------------------. + | Shifts and Gotos. | + `-------------------*/ -/*---------------------------------------. -| Create a new array of N shifts/gotos. | -`---------------------------------------*/ +/*-----------------------------------------. +| Create a new array of NUM shifts/gotos. | +`-----------------------------------------*/ -#define TRANSITIONS_ALLOC(Num) \ - (transitions_t *) xcalloc ((sizeof (transitions_t) \ - + (Num - 1) * sizeof (state_t *)), 1) - -static transitions_t * -transitions_new (int num, state_t **the_states) +static transitions * +transitions_new (int num, state **the_states) { - transitions_t *res = TRANSITIONS_ALLOC (num); + size_t states_size = num * sizeof *the_states; + transitions *res = xmalloc (offsetof (transitions, states) + states_size); res->num = num; - memcpy (res->states, the_states, num * sizeof (the_states[0])); + memcpy (res->states, the_states, states_size); return res; } -/*-------------------------------------------------------------------. -| Return the state such these TRANSITIONS contain a shift/goto to it | -| on SYMBOL. Aborts if none found. | -`-------------------------------------------------------------------*/ +/*-------------------------------------------------------. +| Return the state such that SHIFTS contain a shift/goto | +| to it on SYM. Abort if none found. | +`-------------------------------------------------------*/ -state_t * -transitions_to (transitions_t *shifts, symbol_number_t s) +state * +transitions_to (transitions *shifts, symbol_number sym) { int j; - for (j = 0; j < shifts->num; j++) - if (TRANSITION_SYMBOL (shifts, j) == s) - return shifts->states[j]; - abort (); + for (j = 0; ; j++) + { + aver (j < shifts->num); + if (TRANSITION_SYMBOL (shifts, j) == sym) + return shifts->states[j]; + } } - /*--------------------. - | Error transitions. | - `--------------------*/ - - -/*-------------------------------. -| Create a new array of N errs. | -`-------------------------------*/ + /*--------------------. + | Error transitions. | + `--------------------*/ -#define ERRS_ALLOC(Nerrs) \ - (errs_t *) xcalloc ((sizeof (errs_t) \ - + (Nerrs - 1) * sizeof (symbol_t *)), 1) +/*---------------------------------. +| Create a new array of NUM errs. | +`---------------------------------*/ -errs_t * -errs_new (int num, symbol_t **tokens) +errs * +errs_new (int num, symbol **tokens) { - errs_t *res = ERRS_ALLOC (num); + size_t symbols_size = num * sizeof *tokens; + errs *res = xmalloc (offsetof (errs, symbols) + symbols_size); res->num = num; - memcpy (res->symbols, tokens, num * sizeof (tokens[0])); + memcpy (res->symbols, tokens, symbols_size); return res; } - /*-------------. - | Reductions. | - `-------------*/ - + /*-------------. + | Reductions. | + `-------------*/ -/*-------------------------------------. -| Create a new array of N reductions. | -`-------------------------------------*/ -#define REDUCTIONS_ALLOC(Nreductions) \ - (reductions_t *) xcalloc ((sizeof (reductions_t) \ - + (Nreductions - 1) * sizeof (rule_t *)), 1) +/*---------------------------------------. +| Create a new array of NUM reductions. | +`---------------------------------------*/ -static reductions_t * -reductions_new (int num, rule_t **reductions) +static reductions * +reductions_new (int num, rule **reds) { - reductions_t *res = REDUCTIONS_ALLOC (num); + size_t rules_size = num * sizeof *reds; + reductions *res = xmalloc (offsetof (reductions, rules) + rules_size); res->num = num; - memcpy (res->rules, reductions, num * sizeof (reductions[0])); + res->lookahead_tokens = NULL; + memcpy (res->rules, reds, rules_size); return res; } - /*---------. - | States. | - `---------*/ + /*---------. + | States. | + `---------*/ -state_number_t nstates = 0; +state_number nstates = 0; /* FINAL_STATE is properly set by new_state when it recognizes its accessing symbol: $end. */ -state_t *final_state = NULL; +state *final_state = NULL; -#define STATE_ALLOC(Nitems) \ - (state_t *) xcalloc ((sizeof (state_t) \ - + (Nitems - 1) * sizeof (item_number_t)), 1) /*------------------------------------------------------------------. | 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->state_list = NULL; + res->consistent = 0; res->solved_conflicts = NULL; + res->solved_conflicts_xml = NULL; - res->nitems = core_size; - memcpy (res->items, core, core_size * sizeof (core[0])); + res->nitems = nitems; + memcpy (res->items, core, items_size); state_hash_insert (res); return res; } +state * +state_new_isocore (state const *s) +{ + state *res; + size_t items_size = s->nitems * sizeof *s->items; + + aver (nstates < STATE_NUMBER_MAXIMUM); + + res = xmalloc (offsetof (state, items) + items_size); + res->number = nstates++; + res->accessing_symbol = s->accessing_symbol; + res->transitions = + transitions_new (s->transitions->num, s->transitions->states); + res->reductions = reductions_new (s->reductions->num, s->reductions->rules); + res->errs = NULL; + res->state_list = NULL; + res->consistent = s->consistent; + res->solved_conflicts = NULL; + res->solved_conflicts_xml = NULL; + + res->nitems = s->nitems; + memcpy (res->items, s->items, items_size); + + return res; +} -/*-------------. -| Free STATE. | -`-------------*/ + +/*---------. +| Free S. | +`---------*/ static void -state_free (state_t *state) +state_free (state *s) { - free (state->transitions); - free (state->reductions); - free (state->errs); - free (state); + free (s->transitions); + free (s->reductions); + free (s->errs); + free (s); } -/*-------------------------------. -| Set the transitions of STATE. | -`-------------------------------*/ +/*---------------------------. +| Set the transitions of S. | +`---------------------------*/ void -state_transitions_set (state_t *state, int num, state_t **transitions) +state_transitions_set (state *s, int num, state **trans) { - assert (!state->transitions); - state->transitions = transitions_new (num, transitions); + aver (!s->transitions); + s->transitions = transitions_new (num, trans); } -/*------------------------------. -| Set the reductions of STATE. | -`------------------------------*/ +/*--------------------------. +| Set the reductions of S. | +`--------------------------*/ void -state_reductions_set (state_t *state, int num, rule_t **reductions) +state_reductions_set (state *s, int num, rule **reds) { - assert (!state->reductions); - state->reductions = reductions_new (num, reductions); + aver (!s->reductions); + s->reductions = reductions_new (num, reds); } -/*------------------------. -| Set the errs 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_errs_set (state_t *state, int num, symbol_t **tokens) +state_errs_set (state *s, int num, symbol **tokens) { - assert (!state->errs); - state->errs = errs_new (num, tokens); + 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; - bitset_iterator biter; - int nlookaheads = 0; - /* Count the number of lookaheads corresponding to this rule. */ - for (j = 0; j < state->nlookaheads; ++j) - BITSET_FOR_EACH (biter, state->lookaheads[j], k, 0) - if (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) - BITSET_FOR_EACH (biter, state->lookaheads[j], k, 0) - if (state->lookaheads_rule[j]->number == rule->number) - fprintf (out, "%s%s", - symbols[k]->tag, - --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, "<lookaheads>"); + BITSET_FOR_EACH (biter, reds->lookahead_tokens[red], k, 0) + { + xml_printf (out, level + 1, "<symbol>%s</symbol>", + xml_escape (symbols[k]->tag)); + } + xml_puts (out, level, "</lookaheads>"); + } +} + -/*----------------------. +/*---------------------. | A state hash table. | -`----------------------*/ +`---------------------*/ /* Initial capacity of states hash table. */ #define HT_INITIAL_CAPACITY 257 @@ -251,32 +306,44 @@ 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. | @@ -286,10 +353,10 @@ void state_hash_new (void) { state_table = hash_initialize (HT_INITIAL_CAPACITY, - NULL, - (Hash_hasher) state_hash, - (Hash_comparator) state_compare, - (Hash_data_freer) NULL); + NULL, + state_hasher, + state_comparator, + NULL); } @@ -304,14 +371,15 @@ 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); + if (!hash_insert (state_table, s)) + xalloc_die (); } @@ -320,21 +388,68 @@ 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; /*----------------------. @@ -344,7 +459,7 @@ state_t **states = NULL; void states_free (void) { - state_number_t i; + state_number i; for (i = 0; i < nstates; ++i) state_free (states[i]); free (states);