/* Find and resolve or report look-ahead conflicts for bison,
- Copyright (C) 1984, 1989, 1992, 2000 Free Software Foundation, Inc.
+
+ Copyright (C) 1984, 1989, 1992, 2000, 2001, 2002, 2003
+ Free Software Foundation, Inc.
This file is part of Bison, the GNU Compiler Compiler.
02111-1307, USA. */
#include "system.h"
-#include "getargs.h"
-#include "alloc.h"
+
+#include <bitset.h>
+
+#include "LR0.h"
+#include "complain.h"
+#include "conflicts.h"
#include "files.h"
+#include "getargs.h"
#include "gram.h"
+#include "lalr.h"
+#include "reader.h"
#include "state.h"
+#include "symtab.h"
+/* -1 stands for not specified. */
+int expected_conflicts = -1;
+static char *conflicts = NULL;
+struct obstack solved_conflicts_obstack;
-extern char **tags;
-extern int tokensetsize;
-extern char *consistent;
-extern short *accessing_symbol;
-extern shifts **shift_table;
-extern unsigned *LA;
-extern short *LAruleno;
-extern short *lookaheads;
-extern int fixed_outfiles;
-
-extern void initialize_conflicts PARAMS((void));
-extern void conflict_log PARAMS((void));
-extern void verbose_conflict_log PARAMS((void));
-extern void print_reductions PARAMS((int));
-extern void finalize_conflicts PARAMS((void));
-
-static void set_conflicts PARAMS((int));
-static void resolve_sr_conflict PARAMS((int, int));
-static void flush_shift PARAMS((int, int));
-static void log_resolution PARAMS((int, int, int, char *));
-static void total_conflicts PARAMS((void));
-static void count_sr_conflicts PARAMS((int));
-static void count_rr_conflicts PARAMS((int));
-
-char any_conflicts;
-errs **err_table;
-int expected_conflicts;
-static char *conflicts;
-
-
-static unsigned *shiftset;
-static unsigned *lookaheadset;
-static int src_total;
-static int rrc_total;
-static int src_count;
-static int rrc_count;
+static bitset shiftset;
+static bitset lookaheadset;
+\f
-void
-initialize_conflicts (void)
-{
- register int i;
-/* register errs *sp; JF unused */
-
- conflicts = NEW2(nstates, char);
- shiftset = NEW2(tokensetsize, unsigned);
- lookaheadset = NEW2(tokensetsize, unsigned);
-
- err_table = NEW2(nstates, errs *);
+enum conflict_resolution
+ {
+ shift_resolution,
+ reduce_resolution,
+ left_resolution,
+ right_resolution,
+ nonassoc_resolution
+ };
- any_conflicts = 0;
-
- for (i = 0; i < nstates; i++)
- set_conflicts(i);
-}
+/*----------------------------------------------------------------.
+| Explain how an SR conflict between TOKEN and RULE was resolved: |
+| RESOLUTION. |
+`----------------------------------------------------------------*/
-static void
-set_conflicts (int state)
+static inline void
+log_resolution (rule *r, symbol_number token,
+ enum conflict_resolution resolution)
{
- register int i;
- register int k;
- register shifts *shiftp;
- register unsigned *fp2;
- register unsigned *fp3;
- register unsigned *fp4;
- register unsigned *fp1;
- register int symbol;
-
- if (consistent[state]) return;
-
- for (i = 0; i < tokensetsize; i++)
- lookaheadset[i] = 0;
-
- shiftp = shift_table[state];
- if (shiftp)
+ if (report_flag & report_solved_conflicts)
{
- k = shiftp->nshifts;
- for (i = 0; i < k; i++)
+ /* The description of the resolution. */
+ switch (resolution)
{
- symbol = accessing_symbol[shiftp->shifts[i]];
- if (ISVAR(symbol)) break;
- SETBIT(lookaheadset, symbol);
+ case shift_resolution:
+ case right_resolution:
+ obstack_fgrow2 (&solved_conflicts_obstack,
+ _("\
+ Conflict between rule %d and token %s resolved as shift"),
+ r->number,
+ symbols[token]->tag);
+ break;
+ case reduce_resolution:
+ case left_resolution:
+ obstack_fgrow2 (&solved_conflicts_obstack,
+ _("\
+ Conflict between rule %d and token %s resolved as reduce"),
+ 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"),
+ r->number,
+ symbols[token]->tag);
+ break;
}
- }
- k = lookaheads[state + 1];
- fp4 = lookaheadset + tokensetsize;
+ /* The reason. */
+ switch (resolution)
+ {
+ case shift_resolution:
+ obstack_fgrow2 (&solved_conflicts_obstack,
+ " (%s < %s)",
+ r->prec->tag,
+ symbols[token]->tag);
+ break;
+
+ case reduce_resolution:
+ obstack_fgrow2 (&solved_conflicts_obstack,
+ " (%s < %s)",
+ symbols[token]->tag,
+ r->prec->tag);
+ break;
+
+ case left_resolution:
+ obstack_fgrow1 (&solved_conflicts_obstack,
+ " (%%left %s)",
+ symbols[token]->tag);
+ break;
+
+ case right_resolution:
+ obstack_fgrow1 (&solved_conflicts_obstack,
+ " (%%right %s)",
+ symbols[token]->tag);
+ break;
+ case nonassoc_resolution:
+ obstack_fgrow1 (&solved_conflicts_obstack,
+ " (%%nonassoc %s)",
+ symbols[token]->tag);
+ break;
+ }
+ obstack_sgrow (&solved_conflicts_obstack, ".\n");
+ }
+}
- /* loop over all rules which require lookahead in this state */
- /* first check for shift-reduce conflict, and try to resolve using precedence */
- for (i = lookaheads[state]; i < k; i++)
- if (rprec[LAruleno[i]])
- {
- fp1 = LA + i * tokensetsize;
- fp2 = fp1;
- fp3 = lookaheadset;
+/*------------------------------------------------------------------.
+| Turn off the shift recorded for the specified token in the |
+| specified state. Used when we resolve a shift-reduce conflict in |
+| favor of the reduction. |
+`------------------------------------------------------------------*/
- while (fp3 < fp4)
- {
- if (*fp2++ & *fp3++)
- {
- resolve_sr_conflict(state, i);
- break;
- }
- }
- }
+static void
+flush_shift (state *s, int token)
+{
+ transitions *trans = s->transitions;
+ int i;
+
+ bitset_reset (lookaheadset, token);
+ for (i = 0; i < trans->num; i++)
+ if (!TRANSITION_IS_DISABLED (trans, i)
+ && TRANSITION_SYMBOL (trans, i) == token)
+ TRANSITION_DISABLE (trans, i);
+}
- /* loop over all rules which require lookahead in this state */
- /* Check for conflicts not resolved above. */
- for (i = lookaheads[state]; i < k; i++)
- {
- fp1 = LA + i * tokensetsize;
- fp2 = fp1;
- fp3 = lookaheadset;
+/*-------------------------------------------------------------------.
+| Turn off the reduce recorded for the specified token for the |
+| specified lookahead. Used when we resolve a shift-reduce conflict |
+| in favor of the shift. |
+`-------------------------------------------------------------------*/
- while (fp3 < fp4)
- {
- if (*fp2++ & *fp3++)
- {
- conflicts[state] = 1;
- any_conflicts = 1;
- }
- }
-
- fp2 = fp1;
- fp3 = lookaheadset;
-
- while (fp3 < fp4)
- *fp3++ |= *fp2++;
- }
+static void
+flush_reduce (bitset lookaheads, int token)
+{
+ bitset_reset (lookaheads, token);
}
-
-/* Attempt to resolve shift-reduce conflict for one rule
-by means of precedence declarations.
-It has already been checked that the rule has a precedence.
-A conflict is resolved by modifying the shift or reduce tables
-so that there is no longer a conflict. */
+/*------------------------------------------------------------------.
+| Attempt to resolve shift-reduce conflict for one rule by means of |
+| precedence declarations. It has already been checked that the |
+| rule has a precedence. A conflict is resolved by modifying the |
+| shift or reduce tables so that there is no longer a conflict. |
+| |
+| LOOKAHEAD is the number of the lookahead bitset to consider. |
+| |
+| ERRORS can be used to store discovered explicit errors. |
+`------------------------------------------------------------------*/
static void
-resolve_sr_conflict (int state, int lookaheadnum)
+resolve_sr_conflict (state *s, int ruleno, symbol **errors)
{
- register int i;
- register int mask;
- register unsigned *fp1;
- register unsigned *fp2;
- register int redprec;
- errs *errp = (errs *) xmalloc (sizeof(errs) + ntokens * sizeof(short));
- short *errtokens = errp->errs;
-
- /* find the rule to reduce by to get precedence of reduction */
- redprec = rprec[LAruleno[lookaheadnum]];
-
- mask = 1;
- fp1 = LA + lookaheadnum * tokensetsize;
- fp2 = lookaheadset;
+ symbol_number i;
+ reductions *reds = s->reductions;
+ /* Find the rule to reduce by to get precedence of reduction. */
+ rule *redrule = reds->rules[ruleno];
+ int redprec = redrule->prec->prec;
+ bitset lookaheads = reds->lookaheads[ruleno];
+ int nerrs = 0;
+
for (i = 0; i < ntokens; i++)
- {
- if ((mask & *fp2 & *fp1) && sprec[i])
+ if (bitset_test (lookaheads, i)
+ && bitset_test (lookaheadset, i)
+ && symbols[i]->prec)
+ {
/* Shift-reduce conflict occurs for token number i
and it has a precedence.
The precedence of shifting is that of token i. */
- {
- if (sprec[i] < redprec)
- {
- if (verboseflag) log_resolution(state, lookaheadnum, i, _("reduce"));
- *fp2 &= ~mask; /* flush the shift for this token */
- flush_shift(state, i);
- }
- else if (sprec[i] > redprec)
- {
- if (verboseflag) log_resolution(state, lookaheadnum, i, _("shift"));
- *fp1 &= ~mask; /* flush the reduce for this token */
- }
- else
+ if (symbols[i]->prec < redprec)
+ {
+ log_resolution (redrule, i, reduce_resolution);
+ flush_shift (s, i);
+ }
+ else if (symbols[i]->prec > redprec)
+ {
+ log_resolution (redrule, i, shift_resolution);
+ flush_reduce (lookaheads, i);
+ }
+ else
+ /* Matching precedence levels.
+ For left association, keep only the reduction.
+ For right association, keep only the shift.
+ For nonassociation, keep neither. */
+
+ switch (symbols[i]->assoc)
{
- /* Matching precedence levels.
- For left association, keep only the reduction.
- For right association, keep only the shift.
- For nonassociation, keep neither. */
-
- switch (sassoc[i])
- {
-
- case RIGHT_ASSOC:
- if (verboseflag) log_resolution(state, lookaheadnum, i, _("shift"));
- break;
-
- case LEFT_ASSOC:
- if (verboseflag) log_resolution(state, lookaheadnum, i, _("reduce"));
- break;
-
- case NON_ASSOC:
- if (verboseflag) log_resolution(state, lookaheadnum, i, _("an error"));
- break;
- }
-
- if (sassoc[i] != RIGHT_ASSOC)
- {
- *fp2 &= ~mask; /* flush the shift for this token */
- flush_shift(state, i);
- }
- if (sassoc[i] != LEFT_ASSOC)
- {
- *fp1 &= ~mask; /* flush the reduce for this token */
- }
- if (sassoc[i] == NON_ASSOC)
- {
- /* Record an explicit error for this token. */
- *errtokens++ = i;
- }
+ case right_assoc:
+ log_resolution (redrule, i, right_resolution);
+ flush_reduce (lookaheads, i);
+ break;
+
+ case left_assoc:
+ log_resolution (redrule, i, left_resolution);
+ flush_shift (s, i);
+ break;
+
+ case non_assoc:
+ log_resolution (redrule, i, nonassoc_resolution);
+ flush_shift (s, i);
+ flush_reduce (lookaheads, i);
+ /* Record an explicit error for this token. */
+ errors[nerrs++] = symbols[i];
+ break;
+
+ case undef_assoc:
+ abort ();
}
- }
+ }
- mask <<= 1;
- if (mask == 0)
- {
- mask = 1;
- fp2++; fp1++;
- }
- }
- errp->nerrs = errtokens - errp->errs;
- if (errp->nerrs)
+ /* Some tokens have been explicitly made errors. Allocate a
+ permanent errs structure for this state, to record them. */
+ state_errs_set (s, nerrs, errors);
+
+ if (obstack_object_size (&solved_conflicts_obstack))
{
- /* Some tokens have been explicitly made errors. Allocate
- a permanent errs structure for this state, to record them. */
- i = (char *) errtokens - (char *) errp;
- err_table[state] = (errs *) xmalloc ((unsigned int)i);
- bcopy (errp, err_table[state], i);
+ obstack_1grow (&solved_conflicts_obstack, '\0');
+ s->solved_conflicts = obstack_finish (&solved_conflicts_obstack);
}
- else
- err_table[state] = 0;
- free(errp);
}
-
-/* turn off the shift recorded for the specified token in the specified state.
-Used when we resolve a shift-reduce conflict in favor of the reduction. */
+/*-------------------------------------------------------------------.
+| Solve the S/R conflicts of state S using the |
+| precedence/associativity, and flag it inconsistent if it still has |
+| conflicts. ERRORS can be used as storage to compute the list of |
+| lookaheads on which S raises a syntax error (%nonassoc). |
+`-------------------------------------------------------------------*/
static void
-flush_shift (int state, int token)
+set_conflicts (state *s, symbol **errors)
{
- register shifts *shiftp;
- register int k, i;
-/* register unsigned symbol; JF unused */
-
- shiftp = shift_table[state];
-
- if (shiftp)
- {
- k = shiftp->nshifts;
- for (i = 0; i < k; i++)
- {
- if (shiftp->shifts[i] && token == accessing_symbol[shiftp->shifts[i]])
- (shiftp->shifts[i]) = 0;
- }
- }
-}
-
+ int i;
+ transitions *trans = s->transitions;
+ reductions *reds = s->reductions;
-static void
-log_resolution (int state, int LAno, int token, char *resolution)
-{
- fprintf(foutput,
- _("Conflict in state %d between rule %d and token %s resolved as %s.\n"),
- state, LAruleno[LAno], tags[token], resolution);
-}
+ if (s->consistent)
+ return;
+ bitset_zero (lookaheadset);
-void
-conflict_log (void)
-{
- register int i;
+ FOR_EACH_SHIFT (trans, i)
+ bitset_set (lookaheadset, TRANSITION_SYMBOL (trans, i));
- src_total = 0;
- rrc_total = 0;
+ /* 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 < reds->num; ++i)
+ if (reds->rules[i]->prec && reds->rules[i]->prec->prec
+ && !bitset_disjoint_p (reds->lookaheads[i], lookaheadset))
+ {
+ resolve_sr_conflict (s, i, errors);
+ break;
+ }
- for (i = 0; i < nstates; i++)
+ /* Loop over all rules which require lookahead in this state. Check
+ for conflicts not resolved above. */
+ for (i = 0; i < reds->num; ++i)
{
- if (conflicts[i])
- {
- count_sr_conflicts(i);
- count_rr_conflicts(i);
- src_total += src_count;
- rrc_total += rrc_count;
- }
- }
+ if (!bitset_disjoint_p (reds->lookaheads[i], lookaheadset))
+ conflicts[s->number] = 1;
- total_conflicts();
+ bitset_or (lookaheadset, lookaheadset, reds->lookaheads[i]);
+ }
}
+/*----------------------------------------------------------------.
+| Solve all the S/R conflicts using the precedence/associativity, |
+| and flag as inconsistent the states that still have conflicts. |
+`----------------------------------------------------------------*/
+
void
-verbose_conflict_log (void)
+conflicts_solve (void)
{
- register int i;
+ state_number i;
+ /* List of lookaheads on which we explicitly raise a syntax error. */
+ symbol **errors = MALLOC (errors, ntokens + 1);
- src_total = 0;
- rrc_total = 0;
+ 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++)
{
- if (conflicts[i])
- {
- count_sr_conflicts(i);
- count_rr_conflicts(i);
- src_total += src_count;
- rrc_total += rrc_count;
-
- fprintf(foutput, _("State %d contains"), i);
-
- if (src_count == 1)
- fprintf(foutput, _(" 1 shift/reduce conflict"));
- else if (src_count > 1)
- fprintf(foutput, _(" %d shift/reduce conflicts"), src_count);
-
- if (src_count > 0 && rrc_count > 0)
- fprintf(foutput, _(" and"));
-
- if (rrc_count == 1)
- fprintf(foutput, _(" 1 reduce/reduce conflict"));
- else if (rrc_count > 1)
- fprintf(foutput, _(" %d reduce/reduce conflicts"), rrc_count);
+ set_conflicts (states[i], errors);
- putc('.', foutput);
- putc('\n', foutput);
- }
+ /* For uniformity of the code, make sure all the states have a valid
+ `errs' member. */
+ if (!states[i]->errs)
+ states[i]->errs = errs_new (0, 0);
}
- total_conflicts();
+ free (errors);
}
-static void
-total_conflicts (void)
-{
- if (src_total == expected_conflicts && rrc_total == 0)
- return;
-
- if (fixed_outfiles)
- {
- /* If invoked under the name `yacc', use the output format
- specified by POSIX. */
- fprintf(stderr, _("conflicts: "));
- if (src_total > 0)
- fprintf(stderr, _(" %d shift/reduce"), src_total);
- if (src_total > 0 && rrc_total > 0)
- fprintf(stderr, ",");
- if (rrc_total > 0)
- fprintf(stderr, _(" %d reduce/reduce"), rrc_total);
- putc('\n', stderr);
- }
- else
- {
- fprintf(stderr, _("%s contains"), infile);
-
- if (src_total == 1)
- fprintf(stderr, _(" 1 shift/reduce conflict"));
- else if (src_total > 1)
- fprintf(stderr, _(" %d shift/reduce conflicts"), src_total);
-
- if (src_total > 0 && rrc_total > 0)
- fprintf(stderr, _(" and"));
-
- if (rrc_total == 1)
- fprintf(stderr, _(" 1 reduce/reduce conflict"));
- else if (rrc_total > 1)
- fprintf(stderr, _(" %d reduce/reduce conflicts"), rrc_total);
+/*---------------------------------------------.
+| Count the number of shift/reduce conflicts. |
+`---------------------------------------------*/
- putc('.', stderr);
- putc('\n', stderr);
- }
-}
-
-
-static void
-count_sr_conflicts (int state)
+static int
+count_sr_conflicts (state *s)
{
- register int i;
- register int k;
- register int mask;
- register shifts *shiftp;
- register unsigned *fp1;
- register unsigned *fp2;
- register unsigned *fp3;
- register int symbol;
+ int i;
+ int src_count = 0;
+ transitions *trans = s->transitions;
+ reductions *reds = s->reductions;
- src_count = 0;
+ if (!trans)
+ return 0;
- shiftp = shift_table[state];
- if (!shiftp) return;
+ bitset_zero (lookaheadset);
+ bitset_zero (shiftset);
- for (i = 0; i < tokensetsize; i++)
- {
- shiftset[i] = 0;
- lookaheadset[i] = 0;
- }
+ FOR_EACH_SHIFT (trans, i)
+ bitset_set (shiftset, TRANSITION_SYMBOL (trans, i));
- k = shiftp->nshifts;
- for (i = 0; i < k; i++)
- {
- if (! shiftp->shifts[i]) continue;
- symbol = accessing_symbol[shiftp->shifts[i]];
- if (ISVAR(symbol)) break;
- SETBIT(shiftset, symbol);
- }
+ for (i = 0; i < reds->num; ++i)
+ bitset_or (lookaheadset, lookaheadset, reds->lookaheads[i]);
- k = lookaheads[state + 1];
- fp3 = lookaheadset + tokensetsize;
+ bitset_and (lookaheadset, lookaheadset, shiftset);
- for (i = lookaheads[state]; i < k; i++)
- {
- fp1 = LA + i * tokensetsize;
- fp2 = lookaheadset;
+ src_count = bitset_count (lookaheadset);
+
+ return src_count;
+}
- while (fp2 < fp3)
- *fp2++ |= *fp1++;
- }
- fp1 = shiftset;
- fp2 = lookaheadset;
+/*----------------------------------------------------------------.
+| Count the number of reduce/reduce conflicts. If ONE_PER_TOKEN, |
+| count one conflict for each token that has any reduce/reduce |
+| conflicts. Otherwise, count one conflict for each pair of |
+| conflicting reductions. |
++`----------------------------------------------------------------*/
- while (fp2 < fp3)
- *fp2++ &= *fp1++;
+static int
+count_rr_conflicts (state *s, int one_per_token)
+{
+ int i;
+ reductions *reds = s->reductions;
+ int rrc_count = 0;
- mask = 1;
- fp2 = lookaheadset;
for (i = 0; i < ntokens; i++)
{
- if (mask & *fp2)
- src_count++;
-
- mask <<= 1;
- if (mask == 0)
- {
- mask = 1;
- fp2++;
- }
+ int count = 0;
+ int j;
+ for (j = 0; j < reds->num; ++j)
+ if (bitset_test (reds->lookaheads[j], i))
+ count++;
+
+ if (count >= 2)
+ rrc_count += one_per_token ? 1 : count-1;
}
+
+ return rrc_count;
}
+/*--------------------------------------------------------.
+| Report the number of conflicts, using the Yacc format. |
+`--------------------------------------------------------*/
+
static void
-count_rr_conflicts (int state)
+conflict_report (FILE *out, int src_num, int rrc_num)
{
- register int i;
- register int j;
- register int count;
- register unsigned mask;
- register unsigned *baseword;
- register unsigned *wordp;
- register int m;
- register int n;
-
- rrc_count = 0;
+ 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);
+}
- m = lookaheads[state];
- n = lookaheads[state + 1];
- if (n - m < 2) return;
+/*-----------------------------------------------------------.
+| Output the detailed description of states with conflicts. |
+`-----------------------------------------------------------*/
- mask = 1;
- baseword = LA + m * tokensetsize;
- for (i = 0; i < ntokens; i++)
+void
+conflicts_output (FILE *out)
+{
+ bool printed_sth = false;
+ state_number i;
+ for (i = 0; i < nstates; i++)
{
- wordp = baseword;
-
- count = 0;
- for (j = m; j < n; j++)
- {
- if (mask & *wordp)
- count++;
-
- wordp += tokensetsize;
- }
-
- if (count >= 2) rrc_count++;
-
- mask <<= 1;
- if (mask == 0)
+ state *s = states[i];
+ if (conflicts[i])
{
- mask = 1;
- baseword++;
+ 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);
}
+/*--------------------------------------------------------.
+| Total the number of S/R and R/R conflicts. Unlike the |
+| code in conflicts_output, however, count EACH pair of |
+| reductions for the same state and lookahead as one |
+| conflict. |
+`--------------------------------------------------------*/
-void
-print_reductions (int state)
+int
+conflicts_total_count (void)
{
- register int i;
- register int j;
- register int k;
- register unsigned *fp1;
- register unsigned *fp2;
- register unsigned *fp3;
- register unsigned *fp4;
- register int rule;
- register int symbol;
- register unsigned mask;
- register int m;
- register int n;
- register int default_LA;
- register int default_rule = 0;
- register int cmax;
- register int count;
- register shifts *shiftp;
- register errs *errp;
- int nodefault = 0;
-
- for (i = 0; i < tokensetsize; i++)
- shiftset[i] = 0;
-
- shiftp = shift_table[state];
- if (shiftp)
- {
- k = shiftp->nshifts;
- for (i = 0; i < k; i++)
- {
- if (! shiftp->shifts[i]) continue;
- symbol = accessing_symbol[shiftp->shifts[i]];
- if (ISVAR(symbol)) break;
- /* if this state has a shift for the error token,
- don't use a default rule. */
- if (symbol == error_token_number) nodefault = 1;
- SETBIT(shiftset, symbol);
- }
- }
+ state_number i;
+ int count;
- errp = err_table[state];
- if (errp)
- {
- k = errp->nerrs;
- for (i = 0; i < k; i++)
- {
- if (! errp->errs[i]) continue;
- symbol = errp->errs[i];
- SETBIT(shiftset, symbol);
- }
- }
+ /* Conflicts by state. */
+ count = 0;
+ for (i = 0; i < nstates; i++)
+ if (conflicts[i])
+ {
+ count += count_sr_conflicts (states[i]);
+ count += count_rr_conflicts (states[i], false);
+ }
+ return count;
+}
- m = lookaheads[state];
- n = lookaheads[state + 1];
- if (n - m == 1 && ! nodefault)
- {
- default_rule = LAruleno[m];
+/*------------------------------------------.
+| Reporting the total number of conflicts. |
+`------------------------------------------*/
- fp1 = LA + m * tokensetsize;
- fp2 = shiftset;
- fp3 = lookaheadset;
- fp4 = lookaheadset + tokensetsize;
+void
+conflicts_print (void)
+{
+ /* Is the number of SR conflicts OK? Either EXPECTED_CONFLICTS is
+ not set, and then we want 0 SR, or else it is specified, in which
+ case we want equality. */
+ int src_ok = 0;
- while (fp3 < fp4)
- *fp3++ = *fp1++ & *fp2++;
+ int src_total = 0;
+ int rrc_total = 0;
- mask = 1;
- fp3 = lookaheadset;
+ /* Conflicts by state. */
+ {
+ state_number i;
- for (i = 0; i < ntokens; i++)
+ for (i = 0; i < nstates; i++)
+ if (conflicts[i])
{
- if (mask & *fp3)
- fprintf(foutput, _(" %-4s\t[reduce using rule %d (%s)]\n"),
- tags[i], default_rule, tags[rlhs[default_rule]]);
-
- mask <<= 1;
- if (mask == 0)
- {
- mask = 1;
- fp3++;
- }
+ src_total += count_sr_conflicts (states[i]);
+ rrc_total += count_rr_conflicts (states[i], true);
}
+ }
- fprintf(foutput, _(" $default\treduce using rule %d (%s)\n\n"),
- default_rule, tags[rlhs[default_rule]]);
- }
- else if (n - m >= 1)
- {
- cmax = 0;
- default_LA = -1;
- fp4 = lookaheadset + tokensetsize;
-
- if (! nodefault)
- for (i = m; i < n; i++)
- {
- fp1 = LA + i * tokensetsize;
- fp2 = shiftset;
- fp3 = lookaheadset;
-
- while (fp3 < fp4)
- *fp3++ = *fp1++ & (~(*fp2++));
-
- count = 0;
- mask = 1;
- fp3 = lookaheadset;
- for (j = 0; j < ntokens; j++)
- {
- if (mask & *fp3)
- count++;
-
- mask <<= 1;
- if (mask == 0)
- {
- mask = 1;
- fp3++;
- }
- }
-
- if (count > cmax)
- {
- cmax = count;
- default_LA = i;
- default_rule = LAruleno[i];
- }
-
- fp2 = shiftset;
- fp3 = lookaheadset;
-
- while (fp3 < fp4)
- *fp2++ |= *fp3++;
- }
-
- for (i = 0; i < tokensetsize; i++)
- shiftset[i] = 0;
-
- if (shiftp)
- {
- k = shiftp->nshifts;
- for (i = 0; i < k; i++)
- {
- if (! shiftp->shifts[i]) continue;
- symbol = accessing_symbol[shiftp->shifts[i]];
- if (ISVAR(symbol)) break;
- SETBIT(shiftset, symbol);
- }
- }
-
- mask = 1;
- fp1 = LA + m * tokensetsize;
- fp2 = shiftset;
- for (i = 0; i < ntokens; i++)
- {
- int defaulted = 0;
-
- if (mask & *fp2)
- count = 1;
- else
- count = 0;
+ src_ok = src_total == (expected_conflicts == -1 ? 0 : expected_conflicts);
- fp3 = fp1;
- for (j = m; j < n; j++)
- {
- if (mask & *fp3)
- {
- if (count == 0)
- {
- if (j != default_LA)
- {
- rule = LAruleno[j];
- fprintf(foutput, _(" %-4s\treduce using rule %d (%s)\n"),
- tags[i], rule, tags[rlhs[rule]]);
- }
- else defaulted = 1;
-
- count++;
- }
- else
- {
- if (defaulted)
- {
- rule = LAruleno[default_LA];
- fprintf(foutput, _(" %-4s\treduce using rule %d (%s)\n"),
- tags[i], rule, tags[rlhs[rule]]);
- defaulted = 0;
- }
- rule = LAruleno[j];
- fprintf(foutput, _(" %-4s\t[reduce using rule %d (%s)]\n"),
- tags[i], rule, tags[rlhs[rule]]);
- }
- }
-
- fp3 += tokensetsize;
- }
-
- mask <<= 1;
- if (mask == 0)
- {
- mask = 1;
- /* We tried incrementing just fp1, and just fp2; both seem wrong.
- It seems necessary to increment both in sync. */
- fp1++;
- fp2++;
- }
- }
+ /* If there are no RR conflicts, and as many SR conflicts as
+ expected, then there is nothing to report. */
+ if (!rrc_total && src_ok)
+ return;
- if (default_LA >= 0)
- {
- fprintf(foutput, _(" $default\treduce using rule %d (%s)\n"),
- default_rule, tags[rlhs[default_rule]]);
- }
+ /* Report the total number of conflicts on STDERR. */
+ if (! yacc_flag)
+ fprintf (stderr, "%s: ", current_file);
+ conflict_report (stderr, src_total, rrc_total);
- putc('\n', foutput);
+ if (expected_conflicts != -1)
+ {
+ if (! src_ok)
+ warn (ngettext ("expected %d shift/reduce conflict",
+ "expected %d shift/reduce conflicts",
+ expected_conflicts),
+ expected_conflicts);
+ if (rrc_total)
+ warn (_("expected 0 reduce/reduce conflicts"));
}
}
void
-finalize_conflicts (void)
+conflicts_free (void)
{
- FREE(conflicts);
- FREE(shiftset);
- FREE(lookaheadset);
+ XFREE (conflicts);
+ bitset_free (shiftset);
+ bitset_free (lookaheadset);
+ obstack_free (&solved_conflicts_obstack, NULL);
}
projects / bison.git / blobdiff