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* src/print.c (lookahead_set, state_default_rule): Remove.

Browse Source 
(print_reductions): Replace state_default_rule invocation with
equivalent use of yydefact, which was computed in token_actions in
tables.c.
(print_results): Don't allocate lookahead_set.
This commit is contained in:
Joel E. Denny
2007-03-01 03:40:18 +00:00
parent d3b129885f
commit 0bf9249152
4 changed files with 138 additions and 196 deletions
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72
src/print.c
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@@ -38,9 +38,9 @@
#include "reduce.h"
#include "state.h"
#include "symtab.h"
#include "tables.h"
static bitset shift_set;
static bitset lookahead_set;
#if 0
static void
@@ -206,71 +206,6 @@ print_errs (FILE *out, state *s)
}
/*-------------------------------------------------------------.
| Return the default rule of S if it has one, NULL otherwise. |
`-------------------------------------------------------------*/
static rule *
state_default_rule (state *s)
{
reductions *reds = s->reductions;
rule *default_rule = NULL;
int cmax = 0;
int i;
/* No need for a lookahead. */
if (s->consistent)
return reds->rules[0];
/* 1. Each reduction is possibly masked by the lookahead tokens on which
we shift (S/R conflicts)... */
bitset_zero (shift_set);
{
transitions *trans = s->transitions;
FOR_EACH_SHIFT (trans, i)
{
/* If this state has a shift for the error token, don't use a
default rule. */
if (TRANSITION_IS_ERROR (trans, i))
return NULL;
bitset_set (shift_set, TRANSITION_SYMBOL (trans, i));
}
}
/* 2. Each reduction is possibly masked by the lookahead tokens on which
we raise an error (due to %nonassoc). */
{
errs *errp = s->errs;
for (i = 0; i < errp->num; i++)
if (errp->symbols[i])
bitset_set (shift_set, errp->symbols[i]->number);
}
for (i = 0; i < reds->num; ++i)
{
int count = 0;
/* How many non-masked lookahead tokens are there for this
reduction? */
bitset_andn (lookahead_set, reds->lookahead_tokens[i], shift_set);
count = bitset_count (lookahead_set);
if (count > cmax)
{
cmax = count;
default_rule = reds->rules[i];
}
/* 3. And finally, each reduction is possibly masked by previous
reductions (in R/R conflicts, we keep the first reductions).
*/
bitset_or (shift_set, shift_set, reds->lookahead_tokens[i]);
}
return default_rule;
}
/*-------------------------------------------------------------------------.
| Report a reduction of RULE on LOOKAHEAD_TOKEN (which can be `default'). |
| If not ENABLED, the rule is masked by a shift or a reduce (S/R and |
@@ -314,7 +249,8 @@ print_reductions (FILE *out, state *s)
if (reds->num == 0)
return;
default_rule = state_default_rule (s);
if (yydefact[s->number] != 0)
default_rule = &rules[yydefact[s->number] - 1];
bitset_zero (shift_set);
FOR_EACH_SHIFT (trans, i)
@@ -563,11 +499,9 @@ print_results (void)
new_closure (nritems);
/* Storage for print_reductions. */
shift_set = bitset_create (ntokens, BITSET_FIXED);
lookahead_set = bitset_create (ntokens, BITSET_FIXED);
for (i = 0; i < nstates; i++)
print_state (out, states[i]);
bitset_free (shift_set);
bitset_free (lookahead_set);
if (report_flag & report_itemsets)
free_closure ();