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graphs: address an issue with R/R conflicts

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All disabled reductions should now be shown as such.

* src/graphviz.c (output_red): Here.
(conclude_red): New.

Signed-off-by: Akim Demaille <akim@lrde.epita.fr>
This commit is contained in:
Theophile Ranquet
2012-10-18 15:38:29 +00:00
committed by Akim Demaille
parent 715978d726
commit 85935600ad
1 changed files with 58 additions and 30 deletions
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88
src/graphviz.c
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@@ -93,6 +93,40 @@ no_reduce_bitset_init (state const *s, bitset *no_reduce_set)
bitset_set (*no_reduce_set, s->errs->symbols[n]->number);
}
static void
conclude_red (struct obstack *out, int source, int ruleno, bool enabled,
bool first, FILE *fout)
{
/* If no lookahead tokens were valid transitions, this reduction is
actually hidden, so cancel everything. */
if (first)
return (void) obstack_finish0 (out);
else
{
char const *ed = enabled ? "e" : "d";
/* First, build the edge's head. */
if (! first)
fprintf (fout, " %1$d -> \"%1$dR%2$d%3$s\" [label = \"",
source, ruleno, ed);
/* (The lookahead tokens have been added to the beginning of the
obstack, in the caller function.) */
/* Then, the edge's tail. */
obstack_sgrow (out, "\" style = solid]\n");
/* Build the associated diamond representation or the target rule. */
obstack_printf (out, " \"%dR%d%s\" "
"[style = filled shape = diamond fillcolor = %s "
"label = \"R%d\"]\n",
source, ruleno, ed,
enabled ? "yellowgreen" : "firebrick1",
ruleno);
fprintf (fout, obstack_finish0 (out));
}
}
static bool
print_token (struct obstack *out, bool first, char const *tok)
{
@@ -110,58 +144,52 @@ output_red (state const *s, reductions const *reds, FILE *fout)
bitset no_reduce_set;
int j;
int source = s->number;
struct obstack oout;
struct obstack dout, eout;
no_reduce_bitset_init (s, &no_reduce_set);
obstack_init (&oout);
obstack_init (&dout);
obstack_init (&eout);
for (j = 0; j < reds->num; ++j)
{
bool disabled = false;
bool first = true;
bool defaulted = false;
bool firstd = true, firste = true; // first{en,dis}abled
int ruleno = reds->rules[j]->user_number;
rule *default_reduction = NULL;
if (yydefact[s->number] != 0)
default_reduction = &rules[yydefact[s->number] - 1];
/* First, print the edges that represent each possible reduction for
the given state. */
obstack_printf (&oout, " %1$d -> \"%1$dR%2$d\" [label=\"",
source, ruleno);
/* Build the lookahead tokens lists, one for enabled transitions and one
for disabled transistions. */
if (default_reduction && default_reduction == reds->rules[j])
first = print_token (&oout, true, "$default");
else
{
firste = print_token (&eout, true, "$default");
defaulted = true;
}
if (reds->lookahead_tokens)
{
int i;
for (i = 0; i < ntokens; i++)
if (bitset_test (reds->lookahead_tokens[j], i))
{
first = print_token (&oout, first, symbols[i]->tag);
if (bitset_test (no_reduce_set, i))
disabled = true;
firstd = print_token (&dout, firstd, symbols[i]->tag);
else
{
if (! defaulted)
firste = print_token (&eout, firste, symbols[i]->tag);
bitset_set (no_reduce_set, i);
}
}
}
obstack_sgrow (&oout, "\" style=solid]\n");
/* Then, print the reduction's representation. Done later since
we need to know whether this reduction is disabled. */
obstack_printf (&oout,
" \"%dR%d\" "
"[style=filled shape=diamond fillcolor=%s "
"label=\"R%d\"]\n",
source, ruleno,
disabled ? "firebrick1" : "yellowgreen",
ruleno);
/* If no lookahead tokens were valid transitions, this reduction is
actually disabled, so don't print it. */
if (first)
(void) obstack_finish0 (&oout);
else
fprintf (fout, obstack_finish0 (&oout));
/* Do the actual output. */
conclude_red (&eout, source, ruleno, true, firste, fout);
conclude_red (&dout, source, ruleno, false, firstd, fout);
}
obstack_free (&oout, 0);
obstack_free (&eout, 0);
obstack_free (&dout, 0);
}
void