tree-optimization/73550 - more switch handling improvements for uninit
Commit Message
The following makes predicate analysis handle case labels with
a non-singleton contiguous range.
Bootstrapped and tested on x86_64-unknown-linux-gnu, pushed.
PR tree-optimization/73550
* gimple-predicate-analysis.cc (predicate::init_from_control_deps):
Sanitize debug dumping. Handle case labels with a CASE_HIGH.
(predicate::dump): Adjust for better readability.
---
gcc/gimple-predicate-analysis.cc | 77 +++++++++++++++++++++-----------
1 file changed, 50 insertions(+), 27 deletions(-)
@@ -1674,6 +1674,10 @@ predicate::init_from_control_deps (const vec<edge> *dep_chains,
if (num_chains == 0)
return;
+ if (DEBUG_PREDICATE_ANALYZER && dump_file)
+ fprintf (dump_file, "init_from_control_deps {%s}:\n",
+ format_edge_vecs (dep_chains, num_chains).c_str ());
+
/* Convert the control dependency chain into a set of predicates. */
m_preds.reserve (num_chains);
@@ -1740,7 +1744,8 @@ predicate::init_from_control_deps (const vec<edge> *dep_chains,
if (DEBUG_PREDICATE_ANALYZER && dump_file)
{
- fprintf (dump_file, "one_pred = ");
+ fprintf (dump_file, "%d -> %d: one_pred = ",
+ e->src->index, e->dest->index);
dump_pred_info (one_pred);
fputc ('\n', dump_file);
}
@@ -1773,24 +1778,41 @@ predicate::init_from_control_deps (const vec<edge> *dep_chains,
}
}
/* If more than one label reaches this block or the case
- label doesn't have a single value (like the default one)
- fail. */
- if (!l
- || !CASE_LOW (l)
- || (CASE_HIGH (l)
- && !operand_equal_p (CASE_LOW (l), CASE_HIGH (l), 0)))
+ label doesn't have a contiguous range of values (like the
+ default one) fail. */
+ if (!l || !CASE_LOW (l))
{
has_valid_pred = false;
break;
}
-
- pred_info one_pred;
- one_pred.pred_lhs = gimple_switch_index (gs);
- one_pred.pred_rhs = CASE_LOW (l);
- one_pred.cond_code = EQ_EXPR;
- one_pred.invert = false;
- t_chain.safe_push (one_pred);
- has_valid_pred = true;
+ else if (!CASE_HIGH (l)
+ || operand_equal_p (CASE_LOW (l), CASE_HIGH (l)))
+ {
+ pred_info one_pred;
+ one_pred.pred_lhs = gimple_switch_index (gs);
+ one_pred.pred_rhs = CASE_LOW (l);
+ one_pred.cond_code = EQ_EXPR;
+ one_pred.invert = false;
+ t_chain.safe_push (one_pred);
+ has_valid_pred = true;
+ }
+ else
+ {
+ /* Support a case label with a range with
+ two predicates. We're overcommitting on
+ the MAX_CHAIN_LEN budget by at most a factor
+ of two here. */
+ pred_info one_pred;
+ one_pred.pred_lhs = gimple_switch_index (gs);
+ one_pred.pred_rhs = CASE_LOW (l);
+ one_pred.cond_code = GE_EXPR;
+ one_pred.invert = false;
+ t_chain.safe_push (one_pred);
+ one_pred.pred_rhs = CASE_HIGH (l);
+ one_pred.cond_code = LE_EXPR;
+ t_chain.safe_push (one_pred);
+ has_valid_pred = true;
+ }
}
else
{
@@ -1803,22 +1825,24 @@ predicate::init_from_control_deps (const vec<edge> *dep_chains,
if (!has_valid_pred)
break;
else
- m_preds.safe_push (t_chain);
+ m_preds.quick_push (t_chain);
}
- if (DEBUG_PREDICATE_ANALYZER && dump_file)
+ if (has_valid_pred)
{
- fprintf (dump_file, "init_from_control_deps {%s}:\n",
- format_edge_vecs (dep_chains, num_chains).c_str ());
- dump (NULL, "");
+ gcc_assert (m_preds.length () != 0);
+ if (DEBUG_PREDICATE_ANALYZER && dump_file)
+ dump (NULL, "");
}
-
- if (has_valid_pred)
- gcc_assert (m_preds.length () != 0);
else
- /* Clear M_PREDS to indicate failure. */
- m_preds.release ();
+ {
+ if (DEBUG_PREDICATE_ANALYZER && dump_file)
+ fprintf (dump_file, "\tFAILED\n");
+ /* Clear M_PREDS to indicate failure. */
+ m_preds.release ();
+ }
}
+
/* Store a PRED in *THIS. */
void
@@ -1856,9 +1880,8 @@ predicate::dump (gimple *stmt, const char *msg) const
else
fprintf (dump_file, "\t(");
dump_pred_chain (m_preds[i]);
- fputc (')', dump_file);
+ fprintf (dump_file, ")\n");
}
- fputc ('\n', dump_file);
}
/* Initialize USE_PREDS with the predicates of the control dependence chains