X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/9222837b2743308e4971fc0ad299ca2f73fb20ae..f377f69fec28013c79db4efe12bbb9d48987fb2c:/src/reduce.c?ds=inline diff --git a/src/reduce.c b/src/reduce.c index 7c3ed15d..7bbd8954 100644 --- a/src/reduce.c +++ b/src/reduce.c @@ -111,7 +111,7 @@ useless_nonterminals (void) while (1) { bitset_copy (Np, N); - for (r = 1; r < nrules + 1; r++) + for (r = 0; r < nrules; r++) if (!bitset_test (P, r) && useful_production (r, N)) { @@ -158,18 +158,18 @@ inaccessable_symbols (void) user can know. */ Vp = bitset_create (nsyms, BITSET_FIXED); - Pp = bitset_create (nrules + 1, BITSET_FIXED); + Pp = bitset_create (nrules, BITSET_FIXED); /* If the start symbol isn't useful, then nothing will be useful. */ - if (bitset_test (N, axiom->number - ntokens)) + if (bitset_test (N, accept->number - ntokens)) { - bitset_set (V, axiom->number); + bitset_set (V, accept->number); while (1) { rule_number_t r; bitset_copy (Vp, V); - for (r = 1; r < nrules + 1; r++) + for (r = 0; r < nrules; r++) { if (!bitset_test (Pp, r) && bitset_test (P, r) @@ -194,7 +194,7 @@ inaccessable_symbols (void) V = Vp; /* Tokens 0, 1, and 2 are internal to Bison. Consider them useful. */ - bitset_set (V, eoftoken->number); /* end-of-input token */ + bitset_set (V, endtoken->number); /* end-of-input token */ bitset_set (V, errtoken->number); /* error token */ bitset_set (V, undeftoken->number); /* some undefined token */ @@ -215,10 +215,10 @@ inaccessable_symbols (void) /* A token that was used in %prec should not be warned about. */ { - rule_number_t i; - for (i = 1; i < nrules + 1; i++) - if (rules[i].precsym != 0) - bitset_set (V1, rules[i].precsym->number); + rule_number_t r; + for (r = 0; r < nrules; ++r) + if (rules[r].precsym != 0) + bitset_set (V1, rules[r].precsym->number); } } @@ -234,37 +234,30 @@ reduce_grammar_tables (void) /* Report and flag useless productions. */ { rule_number_t r; - for (r = 1; r < nrules + 1; r++) - { - rules[r].useful = bitset_test (P, r); - if (!rules[r].useful) - { - LOCATION_PRINT (stderr, rules[r].location); - fprintf (stderr, ": %s: %s: ", _("warning"), _("useless rule")); - rule_print (&rules[r], stderr); - } - } + for (r = 0; r < nrules; r++) + rules[r].useful = bitset_test (P, r); + grammar_rules_never_reduced_report (_("useless rule")); } /* Map the nonterminals to their new index: useful first, useless afterwards. Kept for later report. */ { - int useful = 1; - int useless = nrules + 1 - nuseless_productions; - rule_t *rules_sorted = XMALLOC (rule_t, nrules + 1) - 1; + int useful = 0; + int useless = nrules - nuseless_productions; + rule_t *rules_sorted = XMALLOC (rule_t, nrules); rule_number_t r; - for (r = 1; r < nrules + 1; ++r) + for (r = 0; r < nrules; ++r) rules_sorted[rules[r].useful ? useful++ : useless++] = rules[r]; - free (rules + 1); + free (rules); rules = rules_sorted; /* Renumber the rules markers in RITEMS. */ - for (r = 1; r < nrules + 1; ++r) + for (r = 0; r < nrules; ++r) { item_number_t *rhsp = rules[r].rhs; for (/* Nothing. */; *rhsp >= 0; ++rhsp) /* Nothing. */; - *rhsp = item_number_of_rule_number (r); + *rhsp = rule_number_as_item_number (r); rules[r].number = r; } nrules -= nuseless_productions; @@ -274,7 +267,7 @@ reduce_grammar_tables (void) { int r; int length; - for (r = nrules + 1; r < nrules + 1 + nuseless_productions; ++r) + for (r = nrules; r < nrules + nuseless_productions; ++r) { length = rule_rhs_length (&rules[r]); nritems -= length + 1; @@ -307,7 +300,7 @@ nonterminals_reduce (void) LOCATION_PRINT (stderr, symbols[i]->location); fprintf (stderr, ": %s: %s: %s\n", _("warning"), _("useless nonterminal"), - symbol_tag_get (symbols[i])); + symbols[i]->tag); } @@ -326,14 +319,14 @@ nonterminals_reduce (void) { rule_number_t r; - for (r = 1; r < nrules + 1; ++r) + for (r = 0; r < nrules; ++r) { item_number_t *rhsp; for (rhsp = rules[r].rhs; *rhsp >= 0; ++rhsp) if (ISVAR (*rhsp)) *rhsp = symbol_number_as_item_number (nontermmap[*rhsp]); } - axiom->number = nontermmap[axiom->number]; + accept->number = nontermmap[accept->number]; } nsyms -= nuseless_nonterminals; @@ -353,9 +346,9 @@ reduce_output (FILE *out) if (nuseless_nonterminals > 0) { int i; - fprintf (out, "%s\n\n", _("Useless nonterminals:")); + fprintf (out, "%s\n\n", _("Useless nonterminals")); for (i = 0; i < nuseless_nonterminals; ++i) - fprintf (out, " %s\n", symbol_tag_get (symbols[nsyms + i])); + fprintf (out, " %s\n", symbols[nsyms + i]->tag); fputs ("\n\n", out); } @@ -366,9 +359,9 @@ reduce_output (FILE *out) if (!bitset_test (V, i) && !bitset_test (V1, i)) { if (!b) - fprintf (out, "%s\n\n", _("Terminals which are not used:")); + fprintf (out, "%s\n\n", _("Terminals which are not used")); b = TRUE; - fprintf (out, " %s\n", symbol_tag_get (symbols[i])); + fprintf (out, " %s\n", symbols[i]->tag); } if (b) fputs ("\n\n", out); @@ -376,8 +369,7 @@ reduce_output (FILE *out) if (nuseless_productions > 0) grammar_rules_partial_print (out, _("Useless rules"), - nrules + 1, - nuseless_productions + nrules + 1); + rule_useless_p); } @@ -425,7 +417,7 @@ reduce_grammar (void) /* Allocate the global sets used to compute the reduced grammar */ N = bitset_create (nvars, BITSET_FIXED); - P = bitset_create (nrules + 1, BITSET_FIXED); + P = bitset_create (nrules, BITSET_FIXED); V = bitset_create (nsyms, BITSET_FIXED); V1 = bitset_create (nsyms, BITSET_FIXED); @@ -438,9 +430,10 @@ reduce_grammar (void) reduce_print (); - if (!bitset_test (N, axiom->number - ntokens)) - fatal (_("Start symbol %s does not derive any sentence"), - symbol_tag_get (symbols[axiom->number])); + if (!bitset_test (N, accept->number - ntokens)) + fatal_at (startsymbol_location, + _("start symbol %s does not derive any sentence"), + startsymbol->tag); /* First reduce the nonterminals, as they renumber themselves in the whole grammar. If you change the order, nonterms would be @@ -450,7 +443,7 @@ reduce_grammar (void) if (nuseless_productions > 0) reduce_grammar_tables (); - if (trace_flag) + if (trace_flag & trace_grammar) { grammar_dump (stderr, "Reduced Grammar");