X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/52489d44456f33e4543cee350cc3eaea5a4426fe..464c692789eba089bb21ebd3983ebeaa4a8d3312:/src/conflicts.c?ds=inline diff --git a/src/conflicts.c b/src/conflicts.c index cbf385ac..721627f2 100644 --- a/src/conflicts.c +++ b/src/conflicts.c @@ -1,4 +1,5 @@ /* Find and resolve or report look-ahead conflicts for bison, + Copyright (C) 1984, 1989, 1992, 2000, 2001, 2002 Free Software Foundation, Inc. @@ -20,17 +21,19 @@ 02111-1307, USA. */ #include "system.h" -#include "bitset.h" + +#include + +#include "LR0.h" #include "complain.h" -#include "getargs.h" -#include "symtab.h" +#include "conflicts.h" #include "files.h" +#include "getargs.h" #include "gram.h" -#include "state.h" #include "lalr.h" -#include "conflicts.h" #include "reader.h" -#include "LR0.h" +#include "state.h" +#include "symtab.h" /* -1 stands for not specified. */ int expected_conflicts = -1; @@ -42,7 +45,7 @@ static bitset lookaheadset; -enum conflict_resolution_e +enum conflict_resolution { shift_resolution, reduce_resolution, @@ -58,8 +61,8 @@ enum conflict_resolution_e `----------------------------------------------------------------*/ static inline void -log_resolution (rule_t *rule, symbol_number_t token, - enum conflict_resolution_e resolution) +log_resolution (rule *r, symbol_number token, + enum conflict_resolution resolution) { if (report_flag & report_solved_conflicts) { @@ -71,7 +74,7 @@ log_resolution (rule_t *rule, symbol_number_t token, obstack_fgrow2 (&solved_conflicts_obstack, _("\ Conflict between rule %d and token %s resolved as shift"), - rule->number, + r->number, symbols[token]->tag); break; case reduce_resolution: @@ -79,14 +82,14 @@ log_resolution (rule_t *rule, symbol_number_t token, obstack_fgrow2 (&solved_conflicts_obstack, _("\ Conflict between rule %d and token %s resolved as reduce"), - rule->number, + r->number, symbols[token]->tag); break; case nonassoc_resolution: obstack_fgrow2 (&solved_conflicts_obstack, _("\ Conflict between rule %d and token %s resolved as an error"), - rule->number, + r->number, symbols[token]->tag); break; } @@ -97,7 +100,7 @@ log_resolution (rule_t *rule, symbol_number_t token, case shift_resolution: obstack_fgrow2 (&solved_conflicts_obstack, " (%s < %s)", - rule->prec->tag, + r->prec->tag, symbols[token]->tag); break; @@ -105,7 +108,7 @@ log_resolution (rule_t *rule, symbol_number_t token, obstack_fgrow2 (&solved_conflicts_obstack, " (%s < %s)", symbols[token]->tag, - rule->prec->tag); + r->prec->tag); break; case left_resolution: @@ -137,16 +140,16 @@ log_resolution (rule_t *rule, symbol_number_t token, `------------------------------------------------------------------*/ static void -flush_shift (state_t *state, int token) +flush_shift (state *s, int token) { - transitions_t *transitions = state->transitions; + transitions *trans = s->transitions; int i; bitset_reset (lookaheadset, token); - for (i = 0; i < transitions->num; i++) - if (!TRANSITION_IS_DISABLED (transitions, i) - && TRANSITION_SYMBOL (transitions, i) == token) - TRANSITION_DISABLE (transitions, i); + for (i = 0; i < trans->num; i++) + if (!TRANSITION_IS_DISABLED (trans, i) + && TRANSITION_SYMBOL (trans, i) == token) + TRANSITION_DISABLE (trans, i); } @@ -171,18 +174,18 @@ flush_reduce (bitset lookaheads, int token) | | | LOOKAHEAD is the number of the lookahead bitset to consider. | | | -| ERRS can be used to store discovered explicit errors. | +| ERRORS can be used to store discovered explicit errors. | `------------------------------------------------------------------*/ static void -resolve_sr_conflict (state_t *state, int lookahead, - symbol_t **errs) +resolve_sr_conflict (state *s, int ruleno, symbol **errors) { - symbol_number_t i; + symbol_number i; + reductions *reds = s->reductions; /* Find the rule to reduce by to get precedence of reduction. */ - rule_t *redrule = state->lookaheads_rule[lookahead]; + rule *redrule = reds->rules[ruleno]; int redprec = redrule->prec->prec; - bitset lookaheads = state->lookaheads[lookahead]; + bitset lookaheads = reds->lookaheads[ruleno]; int nerrs = 0; for (i = 0; i < ntokens; i++) @@ -196,7 +199,7 @@ resolve_sr_conflict (state_t *state, int lookahead, if (symbols[i]->prec < redprec) { log_resolution (redrule, i, reduce_resolution); - flush_shift (state, i); + flush_shift (s, i); } else if (symbols[i]->prec > redprec) { @@ -218,76 +221,75 @@ resolve_sr_conflict (state_t *state, int lookahead, case left_assoc: log_resolution (redrule, i, left_resolution); - flush_shift (state, i); + flush_shift (s, i); break; case non_assoc: log_resolution (redrule, i, nonassoc_resolution); - flush_shift (state, i); + flush_shift (s, i); flush_reduce (lookaheads, i); /* Record an explicit error for this token. */ - errs[nerrs++] = symbols[i]; + errors[nerrs++] = symbols[i]; break; case undef_assoc: - assert (symbols[i]->assoc != undef_assoc); - break; + abort (); } } /* Some tokens have been explicitly made errors. Allocate a permanent errs structure for this state, to record them. */ - state_errs_set (state, nerrs, errs); + state_errs_set (s, nerrs, errors); if (obstack_object_size (&solved_conflicts_obstack)) { obstack_1grow (&solved_conflicts_obstack, '\0'); - state->solved_conflicts = obstack_finish (&solved_conflicts_obstack); + s->solved_conflicts = obstack_finish (&solved_conflicts_obstack); } } /*-------------------------------------------------------------------. -| Solve the S/R conflicts of STATE using the | +| Solve the S/R conflicts of state S using the | | precedence/associativity, and flag it inconsistent if it still has | -| conflicts. ERRS can be used as storage to compute the list of | -| lookaheads on which this STATE raises a parse error (%nonassoc). | +| conflicts. ERRORS can be used as storage to compute the list of | +| lookaheads on which S raises a syntax error (%nonassoc). | `-------------------------------------------------------------------*/ static void -set_conflicts (state_t *state, symbol_t **errs) +set_conflicts (state *s, symbol **errors) { int i; - transitions_t *transitions = state->transitions; + transitions *trans = s->transitions; + reductions *reds = s->reductions; - if (state->consistent) + if (s->consistent) return; bitset_zero (lookaheadset); - FOR_EACH_SHIFT (transitions, i) - bitset_set (lookaheadset, TRANSITION_SYMBOL (transitions, i)); + FOR_EACH_SHIFT (trans, i) + bitset_set (lookaheadset, TRANSITION_SYMBOL (trans, i)); /* Loop over all rules which require lookahead in this state. First check for shift-reduce conflict, and try to resolve using precedence. */ - for (i = 0; i < state->nlookaheads; ++i) - if (state->lookaheads_rule[i]->prec - && state->lookaheads_rule[i]->prec->prec - && !bitset_disjoint_p (state->lookaheads[i], lookaheadset)) + for (i = 0; i < reds->num; ++i) + if (reds->rules[i]->prec && reds->rules[i]->prec->prec + && !bitset_disjoint_p (reds->lookaheads[i], lookaheadset)) { - resolve_sr_conflict (state, i, errs); + resolve_sr_conflict (s, i, errors); break; } /* Loop over all rules which require lookahead in this state. Check for conflicts not resolved above. */ - for (i = 0; i < state->nlookaheads; ++i) + for (i = 0; i < reds->num; ++i) { - if (!bitset_disjoint_p (state->lookaheads[i], lookaheadset)) - conflicts[state->number] = 1; + if (!bitset_disjoint_p (reds->lookaheads[i], lookaheadset)) + conflicts[s->number] = 1; - bitset_or (lookaheadset, lookaheadset, state->lookaheads[i]); + bitset_or (lookaheadset, lookaheadset, reds->lookaheads[i]); } } @@ -300,18 +302,18 @@ set_conflicts (state_t *state, symbol_t **errs) void conflicts_solve (void) { - state_number_t i; - /* List of lookaheads on which we explicitly raise a parse error. */ - symbol_t **errs = XMALLOC (symbol_t *, ntokens + 1); + state_number i; + /* List of lookaheads on which we explicitly raise a syntax error. */ + symbol **errors = MALLOC (errors, ntokens + 1); - conflicts = XCALLOC (char, nstates); + CALLOC (conflicts, nstates); shiftset = bitset_create (ntokens, BITSET_FIXED); lookaheadset = bitset_create (ntokens, BITSET_FIXED); obstack_init (&solved_conflicts_obstack); for (i = 0; i < nstates; i++) { - set_conflicts (states[i], errs); + set_conflicts (states[i], errors); /* For uniformity of the code, make sure all the states have a valid `errs' member. */ @@ -319,7 +321,7 @@ conflicts_solve (void) states[i]->errs = errs_new (0, 0); } - free (errs); + free (errors); } @@ -328,23 +330,24 @@ conflicts_solve (void) `---------------------------------------------*/ static int -count_sr_conflicts (state_t *state) +count_sr_conflicts (state *s) { int i; int src_count = 0; - transitions_t *transitions = state->transitions; + transitions *trans = s->transitions; + reductions *reds = s->reductions; - if (!transitions) + if (!trans) return 0; bitset_zero (lookaheadset); bitset_zero (shiftset); - FOR_EACH_SHIFT (transitions, i) - bitset_set (shiftset, TRANSITION_SYMBOL (transitions, i)); + FOR_EACH_SHIFT (trans, i) + bitset_set (shiftset, TRANSITION_SYMBOL (trans, i)); - for (i = 0; i < state->nlookaheads; ++i) - bitset_or (lookaheadset, lookaheadset, state->lookaheads[i]); + for (i = 0; i < reds->num; ++i) + bitset_or (lookaheadset, lookaheadset, reds->lookaheads[i]); bitset_and (lookaheadset, lookaheadset, shiftset); @@ -362,20 +365,18 @@ count_sr_conflicts (state_t *state) +`----------------------------------------------------------------*/ static int -count_rr_conflicts (state_t *state, int one_per_token) +count_rr_conflicts (state *s, int one_per_token) { int i; + reductions *reds = s->reductions; int rrc_count = 0; - if (state->nlookaheads < 2) - return 0; - for (i = 0; i < ntokens; i++) { int count = 0; int j; - for (j = 0; j < state->nlookaheads; ++j) - if (bitset_test (state->lookaheads[j], i)) + for (j = 0; j < reds->num; ++j) + if (bitset_test (reds->lookaheads[j], i)) count++; if (count >= 2) @@ -386,60 +387,20 @@ count_rr_conflicts (state_t *state, int one_per_token) } -/*--------------------------------------------------------------. -| Return a human readable string which reports shift/reduce and | -| reduce/reduce conflict numbers (SRC_NUM, RRC_NUM). | -`--------------------------------------------------------------*/ - -static const char * -conflict_report (int src_num, int rrc_num) -{ - static char res[4096]; - char *cp = res; - - if (src_num >= 1) - { - sprintf (cp, ngettext ("%d shift/reduce conflict", - "%d shift/reduce conflicts", src_num), src_num); - cp += strlen (cp); - } - - if (src_num > 0 && rrc_num > 0) - { - sprintf (cp, " %s ", _("and")); - cp += strlen (cp); - } - - if (rrc_num >= 1) - { - sprintf (cp, ngettext ("%d reduce/reduce conflict", - "%d reduce/reduce conflicts", rrc_num), rrc_num); - cp += strlen (cp); - } - - *cp++ = '\0'; - - return res; -} - - -/*----------------------------------------------------------------. -| Same as above, but report the number of conflicts a` la POSIX. | -`----------------------------------------------------------------*/ +/*--------------------------------------------------------. +| Report the number of conflicts, using the Yacc format. | +`--------------------------------------------------------*/ static void -conflict_report_yacc (int src_num, int rrc_num) +conflict_report (FILE *out, int src_num, int rrc_num) { - /* If invoked with `--yacc', use the output format specified by - POSIX. */ - fprintf (stderr, _("conflicts: ")); - if (src_num > 0) - fprintf (stderr, _(" %d shift/reduce"), src_num); - if (src_num > 0 && rrc_num > 0) - fprintf (stderr, ","); - if (rrc_num > 0) - fprintf (stderr, _(" %d reduce/reduce"), rrc_num); - putc ('\n', stderr); + if (src_num && rrc_num) + fprintf (out, _("conflicts: %d shift/reduce, %d reduce/reduce\n"), + src_num, rrc_num); + else if (src_num) + fprintf (out, _("conflicts: %d shift/reduce\n"), src_num); + else if (rrc_num) + fprintf (out, _("conflicts: %d reduce/reduce\n"), rrc_num); } @@ -450,43 +411,21 @@ conflict_report_yacc (int src_num, int rrc_num) void conflicts_output (FILE *out) { - bool printed_sth = FALSE; - bool *used_rules = XCALLOC (bool, nrules); - state_number_t i; + bool printed_sth = false; + state_number i; for (i = 0; i < nstates; i++) { - state_t *s = states[i]; - int j; - for (j = 0; j < s->reductions->num; ++j) - used_rules[s->reductions->rules[j]->number] = TRUE; + state *s = states[i]; if (conflicts[i]) { - fprintf (out, _("State %d contains "), i); - fprintf (out, "%s.\n", - conflict_report (count_sr_conflicts (s), - count_rr_conflicts (s, TRUE))); - printed_sth = TRUE; + fprintf (out, _("State %d "), i); + conflict_report (out, count_sr_conflicts (s), + count_rr_conflicts (s, true)); + printed_sth = true; } } if (printed_sth) fputs ("\n\n", out); - - for (i = 0; i < nstates; i++) - { - state_t *s = states[i]; - reductions_t *r = s->reductions; - int j; - for (j = 0; j < r->num; ++j) - if (!used_rules[r->rules[j]->number]) - { - LOCATION_PRINT (stderr, r->rules[j]->location); - fprintf (stderr, ": %s: %s: ", - _("warning"), - _("rule never reduced because of conflicts")); - rule_print (r->rules[j], stderr); - } - } - free (used_rules); } /*--------------------------------------------------------. @@ -499,7 +438,7 @@ conflicts_output (FILE *out) int conflicts_total_count (void) { - state_number_t i; + state_number i; int count; /* Conflicts by state. */ @@ -508,7 +447,7 @@ conflicts_total_count (void) if (conflicts[i]) { count += count_sr_conflicts (states[i]); - count += count_rr_conflicts (states[i], FALSE); + count += count_rr_conflicts (states[i], false); } return count; } @@ -531,13 +470,13 @@ conflicts_print (void) /* Conflicts by state. */ { - state_number_t i; + state_number i; for (i = 0; i < nstates; i++) if (conflicts[i]) { src_total += count_sr_conflicts (states[i]); - rrc_total += count_rr_conflicts (states[i], TRUE); + rrc_total += count_rr_conflicts (states[i], true); } } @@ -549,16 +488,20 @@ conflicts_print (void) return; /* Report the total number of conflicts on STDERR. */ - if (yacc_flag) - conflict_report_yacc (src_total, rrc_total); - else - warn ("%s", conflict_report (src_total, rrc_total)); - - if (expected_conflicts != -1 && !src_ok) - complain (ngettext ("expected %d shift/reduce conflict", - "expected %d shift/reduce conflicts", - expected_conflicts), - expected_conflicts); + if (! yacc_flag) + fprintf (stderr, "%s: ", current_file); + conflict_report (stderr, src_total, rrc_total); + + if (expected_conflicts != -1) + { + if (! src_ok) + complain (ngettext ("expected %d shift/reduce conflict", + "expected %d shift/reduce conflicts", + expected_conflicts), + expected_conflicts); + if (rrc_total) + complain (_("expected 0 reduce/reduce conflicts")); + } }