X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/742e4900c8b05c8c1f56985288141c890f1e9c73..09ccae9b18a7c09ebf7bb8df2a18c8c4a6def248:/src/conflicts.c diff --git a/src/conflicts.c b/src/conflicts.c index 7bb3e08e..05545b20 100644 --- a/src/conflicts.c +++ b/src/conflicts.c @@ -1,24 +1,22 @@ /* Find and resolve or report lookahead conflicts for bison, - Copyright (C) 1984, 1989, 1992, 2000, 2001, 2002, 2003, 2004, 2005, 2006 - Free Software Foundation, Inc. + Copyright (C) 1984, 1989, 1992, 2000, 2001, 2002, 2003, 2004, 2005, 2006, + 2007, 2008 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 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. + 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 3 of the License, or + (at your option) any later version. - Bison 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. + 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., 51 Franklin Street, Fifth Floor, Boston, MA - 02110-1301, USA. */ + along with this program. If not, see . */ #include #include "system.h" @@ -32,6 +30,7 @@ #include "getargs.h" #include "gram.h" #include "lalr.h" +#include "print-xml.h" #include "reader.h" #include "state.h" #include "symtab.h" @@ -41,6 +40,7 @@ int expected_sr_conflicts = -1; int expected_rr_conflicts = -1; static char *conflicts; static struct obstack solved_conflicts_obstack; +static struct obstack solved_conflicts_xml_obstack; static bitset shift_set; static bitset lookahead_set; @@ -74,23 +74,25 @@ log_resolution (rule *r, symbol_number token, case shift_resolution: case right_resolution: obstack_fgrow2 (&solved_conflicts_obstack, - _("\ - Conflict between rule %d and token %s resolved as shift"), + _(" 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"), + _(" 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"), + _(" Conflict between rule %d and token %s" + " resolved as an error"), r->number, symbols[token]->tag); break; @@ -124,21 +126,95 @@ log_resolution (rule *r, symbol_number token, " (%%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"); } + + /* XML report */ + if (xml_flag) + { + /* The description of the resolution. */ + switch (resolution) + { + case shift_resolution: + case right_resolution: + obstack_fgrow2 (&solved_conflicts_xml_obstack, + " ", + r->number, + xml_escape (symbols[token]->tag)); + break; + + case reduce_resolution: + case left_resolution: + obstack_fgrow2 (&solved_conflicts_xml_obstack, + " ", + r->number, + xml_escape (symbols[token]->tag)); + break; + + case nonassoc_resolution: + obstack_fgrow2 (&solved_conflicts_xml_obstack, + " ", + r->number, + xml_escape (symbols[token]->tag)); + break; + } + + /* The reason. */ + switch (resolution) + { + case shift_resolution: + obstack_fgrow2 (&solved_conflicts_xml_obstack, + "%s < %s", + xml_escape_n (0, r->prec->tag), + xml_escape_n (1, symbols[token]->tag)); + break; + + case reduce_resolution: + obstack_fgrow2 (&solved_conflicts_xml_obstack, + "%s < %s", + xml_escape_n (0, symbols[token]->tag), + xml_escape_n (1, r->prec->tag)); + break; + + case left_resolution: + obstack_fgrow1 (&solved_conflicts_xml_obstack, + "%%left %s", + xml_escape (symbols[token]->tag)); + break; + + case right_resolution: + obstack_fgrow1 (&solved_conflicts_xml_obstack, + "%%right %s", + xml_escape (symbols[token]->tag)); + break; + + case nonassoc_resolution: + obstack_fgrow1 (&solved_conflicts_xml_obstack, + "%%nonassoc %s", + xml_escape (symbols[token]->tag)); + break; + } + + obstack_sgrow (&solved_conflicts_xml_obstack, "\n"); + } } /*------------------------------------------------------------------. | 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. | +| favor of the reduction or as an error (%nonassoc). | `------------------------------------------------------------------*/ static void @@ -156,9 +232,9 @@ flush_shift (state *s, int token) /*--------------------------------------------------------------------. -| 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. | +| Turn off the reduce recorded for the specified token in the | +| specified lookahead set. Used when we resolve a shift-reduce | +| conflict in favor of the shift or as an error (%nonassoc). | `--------------------------------------------------------------------*/ static void @@ -176,11 +252,12 @@ flush_reduce (bitset lookahead_tokens, int token) | | | RULENO is the number of the lookahead bitset to consider. | | | -| ERRORS can be used to store discovered explicit errors. | +| ERRORS and NERRS can be used to store discovered explicit | +| errors. | `------------------------------------------------------------------*/ static void -resolve_sr_conflict (state *s, int ruleno, symbol **errors) +resolve_sr_conflict (state *s, int ruleno, symbol **errors, int *nerrs) { symbol_number i; reductions *reds = s->reductions; @@ -188,7 +265,6 @@ resolve_sr_conflict (state *s, int ruleno, symbol **errors) rule *redrule = reds->rules[ruleno]; int redprec = redrule->prec->prec; bitset lookahead_tokens = reds->lookahead_tokens[ruleno]; - int nerrs = 0; for (i = 0; i < ntokens; i++) if (bitset_test (lookahead_tokens, i) @@ -209,16 +285,21 @@ resolve_sr_conflict (state *s, int ruleno, symbol **errors) flush_reduce (lookahead_tokens, i); } else - /* Matching precedence levels. - For left association, keep only the reduction. - For right association, keep only the shift. - For nonassociation, keep neither. */ + /* Matching precedence levels. + For non-defined associativity, keep both: unexpected + associativity conflict. + For left associativity, keep only the reduction. + For right associativity, keep only the shift. + For nonassociativity, keep neither. */ switch (symbols[i]->assoc) { - default: + case undef_assoc: abort (); + case precedence_assoc: + break; + case right_assoc: log_resolution (redrule, i, right_resolution); flush_reduce (lookahead_tokens, i); @@ -234,23 +315,10 @@ resolve_sr_conflict (state *s, int ruleno, symbol **errors) flush_shift (s, i); flush_reduce (lookahead_tokens, i); /* Record an explicit error for this token. */ - errors[nerrs++] = symbols[i]; + errors[(*nerrs)++] = symbols[i]; break; } } - - if (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)) - { - obstack_1grow (&solved_conflicts_obstack, '\0'); - s->solved_conflicts = obstack_finish (&solved_conflicts_obstack); - } } @@ -267,6 +335,7 @@ set_conflicts (state *s, symbol **errors) int i; transitions *trans = s->transitions; reductions *reds = s->reductions; + int nerrs = 0; if (s->consistent) return; @@ -282,7 +351,24 @@ set_conflicts (state *s, symbol **errors) for (i = 0; i < reds->num; ++i) if (reds->rules[i]->prec && reds->rules[i]->prec->prec && !bitset_disjoint_p (reds->lookahead_tokens[i], lookahead_set)) - resolve_sr_conflict (s, i, errors); + resolve_sr_conflict (s, i, errors, &nerrs); + + if (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)) + { + obstack_1grow (&solved_conflicts_obstack, '\0'); + s->solved_conflicts = obstack_finish (&solved_conflicts_obstack); + } + if (obstack_object_size (&solved_conflicts_xml_obstack)) + { + obstack_1grow (&solved_conflicts_xml_obstack, '\0'); + s->solved_conflicts_xml = obstack_finish (&solved_conflicts_xml_obstack); + } /* Loop over all rules which require lookahead in this state. Check for conflicts not resolved above. */ @@ -290,7 +376,6 @@ set_conflicts (state *s, symbol **errors) { if (!bitset_disjoint_p (reds->lookahead_tokens[i], lookahead_set)) conflicts[s->number] = 1; - bitset_or (lookahead_set, lookahead_set, reds->lookahead_tokens[i]); } } @@ -312,6 +397,7 @@ conflicts_solve (void) shift_set = bitset_create (ntokens, BITSET_FIXED); lookahead_set = bitset_create (ntokens, BITSET_FIXED); obstack_init (&solved_conflicts_obstack); + obstack_init (&solved_conflicts_xml_obstack); for (i = 0; i < nstates; i++) { @@ -327,6 +413,17 @@ conflicts_solve (void) } +void +conflicts_update_state_numbers (state_number old_to_new[], + state_number nstates_old) +{ + state_number i; + for (i = 0; i < nstates_old; ++i) + if (old_to_new[i] != nstates_old) + conflicts[old_to_new[i]] = conflicts[i]; +} + + /*---------------------------------------------. | Count the number of shift/reduce conflicts. | `---------------------------------------------*/ @@ -532,4 +629,5 @@ conflicts_free (void) bitset_free (shift_set); bitset_free (lookahead_set); obstack_free (&solved_conflicts_obstack, NULL); + obstack_free (&solved_conflicts_xml_obstack, NULL); }