- Copyright (C) 1984, 1986, 1989, 2000, 2001, 2002, 2003, 2004, 2005,
- 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
+ Copyright (C) 1984, 1986, 1989, 2000-2015 Free Software Foundation,
+ Inc.
-/* Compute how to make the finite state machine deterministic; find
- which rules need lookahead in each state, and which lookahead
+/* Find which rules need lookahead in each state, and which lookahead
ngotos = 0;
for (s = 0; s < nstates; ++s)
{
transitions *sp = states[s]->transitions;
int i;
for (i = sp->num - 1; i >= 0 && TRANSITION_IS_GOTO (sp, i); --i)
ngotos = 0;
for (s = 0; s < nstates; ++s)
{
transitions *sp = states[s]->transitions;
int i;
for (i = sp->num - 1; i >= 0 && TRANSITION_IS_GOTO (sp, i); --i)
transitions *sp = states[s]->transitions;
int i;
for (i = sp->num - 1; i >= 0 && TRANSITION_IS_GOTO (sp, i); --i)
transitions *sp = states[s]->transitions;
int i;
for (i = sp->num - 1; i >= 0 && TRANSITION_IS_GOTO (sp, i); --i)
- {
- goto_number k = temp_map[TRANSITION_SYMBOL (sp, i) - ntokens]++;
- from_state[k] = s;
- to_state[k] = sp->states[i]->number;
- }
+ {
+ goto_number k = temp_map[TRANSITION_SYMBOL (sp, i) - ntokens]++;
+ from_state[k] = s;
+ to_state[k] = sp->states[i]->number;
+ }
- {
- symbol_number sym = TRANSITION_SYMBOL (sp, j);
- if (nullable[sym - ntokens])
- edge[nedges++] = map_goto (stateno, sym);
- }
+ {
+ symbol_number sym = TRANSITION_SYMBOL (sp, j);
+ if (nullable[sym - ntokens])
+ edge[nedges++] = map_goto (stateno, sym);
+ }
- {
- reads[i] = xnmalloc (nedges + 1, sizeof reads[i][0]);
- memcpy (reads[i], edge, nedges * sizeof edge[0]);
- reads[i][nedges] = END_NODE;
- nedges = 0;
- }
+ {
+ reads[i] = xnmalloc (nedges + 1, sizeof reads[i][0]);
+ memcpy (reads[i], edge, nedges * sizeof edge[0]);
+ reads[i][nedges] = END_NODE;
+ nedges = 0;
+ }
- {
- bool done;
- int length = 1;
- item_number const *rp;
- state *s = states[from_state[i]];
- states1[0] = s->number;
-
- for (rp = (*rulep)->rhs; ! item_number_is_rule_number (*rp); rp++)
- {
- s = transitions_to (s->transitions,
- item_number_as_symbol_number (*rp));
- states1[length++] = s->number;
- }
-
- if (!s->consistent)
- add_lookback_edge (s, *rulep, i);
-
- length--;
- done = false;
- while (!done)
- {
- done = true;
- /* Each rhs ends in a rule number, and there is a
- sentinel (ritem[-1]=0) before the first rhs, so it is safe to
- decrement RP here. */
- rp--;
- if (ISVAR (*rp))
- {
- /* Downcasting from item_number to symbol_number. */
- edge[nedges++] = map_goto (states1[--length],
- item_number_as_symbol_number (*rp));
- if (nullable[*rp - ntokens])
- done = false;
- }
- }
- }
+ {
+ bool done;
+ int length = 1;
+ item_number const *rp;
+ state *s = states[from_state[i]];
+ states1[0] = s->number;
+
+ for (rp = (*rulep)->rhs; ! item_number_is_rule_number (*rp); rp++)
+ {
+ s = transitions_to (s->transitions,
+ item_number_as_symbol_number (*rp));
+ states1[length++] = s->number;
+ }
+
+ if (!s->consistent)
+ add_lookback_edge (s, *rulep, i);
+
+ length--;
+ done = false;
+ while (!done)
+ {
+ done = true;
+ /* Each rhs ends in a rule number, and there is a
+ sentinel (ritem[-1]=0) before the first rhs, so it is safe to
+ decrement RP here. */
+ rp--;
+ if (ISVAR (*rp))
+ {
+ /* Downcasting from item_number to symbol_number. */
+ edge[nedges++] = map_goto (states1[--length],
+ item_number_as_symbol_number (*rp));
+ if (nullable[*rp - ntokens])
+ done = false;
+ }
+ }
+ }
- {
- int j;
- includes[i] = xnmalloc (nedges + 1, sizeof includes[i][0]);
- for (j = 0; j < nedges; j++)
- includes[i][j] = edge[j];
- includes[i][nedges] = END_NODE;
- }
+ {
+ int j;
+ includes[i] = xnmalloc (nedges + 1, sizeof includes[i][0]);
+ for (j = 0; j < nedges; j++)
+ includes[i][j] = edge[j];
+ includes[i][nedges] = END_NODE;
+ }
/* We need a lookahead either to distinguish different reductions
(i.e., there are two or more), or to distinguish a reduction from a
shift. Otherwise, it is straightforward, and the state is
/* We need a lookahead either to distinguish different reductions
(i.e., there are two or more), or to distinguish a reduction from a
shift. Otherwise, it is straightforward, and the state is
- `consistent'. However, for states that have any rules, treat only
- the accepting state as consistent (since there is never a lookahead
- token that makes sense there, and so no lookahead token should be
- read) if the user has otherwise disabled default rules. */
+ 'consistent'. However, do not treat a state with any reductions as
+ consistent unless it is the accepting state (because there is never
+ a lookahead token that makes sense there, and so no lookahead token
+ should be read) if the user has otherwise disabled default
+ reductions. */
if (rp->num > 1
|| (rp->num == 1 && sp->num && TRANSITION_IS_SHIFT (sp, 0))
|| (rp->num == 1 && rp->rules[0]->number != 0
if (rp->num > 1
|| (rp->num == 1 && sp->num && TRANSITION_IS_SHIFT (sp, 0))
|| (rp->num == 1 && rp->rules[0]->number != 0
- char *default_rules = muscle_percent_define_get ("lr.default_rules");
- default_rule_only_for_accept = 0 == strcmp (default_rules, "accepting");
- free (default_rules);
+ char *default_reductions =
+ muscle_percent_define_get ("lr.default-reduction");
+ default_reduction_only_for_accept = STREQ (default_reductions, "accepting");
+ free (default_reductions);
fprintf (out, "Lookahead tokens: BEGIN\n");
for (i = 0; i < nstates; ++i)
{
fprintf (out, "Lookahead tokens: BEGIN\n");
for (i = 0; i < nstates; ++i)
{
- for (j = 0; j < reds->num; ++j)
- BITSET_FOR_EACH (iter, reds->lookahead_tokens[j], k, 0)
- {
- fprintf (out, " on %d (%s) -> rule %d\n",
- k, symbols[k]->tag,
- reds->rules[j]->number);
- };
+ {
+ int j, k;
+ for (j = 0; j < reds->num; ++j)
+ BITSET_FOR_EACH (iter, reds->lookahead_tokens[j], k, 0)
+ fprintf (out, " on %d (%s) -> rule %d\n",
+ k, symbols[k]->tag,
+ reds->rules[j]->number);
+ }
projects / bison.git / blobdiff