This is the followup as mentioned in
https://gcc.gnu.org/pipermail/gcc-patches/2024-November/667987.html .
We need to canonicalize the compares using tree_swap_operands_p instead
of checking CONSTANT_CLASS_P.
Bootstrapped and tested on x86_64-linux-gnu.
gcc/ChangeLog:
* tree-ssa-sccvn.cc (visit_phi): Swap the operands
before calling vn_nary_op_lookup_pieces if
tree_swap_operands_p returns true.
(insert_predicates_for_cond): Use tree_swap_operands_p
instead of checking for CONSTANT_CLASS_P.
(process_bb): Swap the comparison and operands
if tree_swap_operands_p returns true.
Signed-off-by: Andrew Pinski <quic_apin...@quicinc.com>
---
gcc/tree-ssa-sccvn.cc | 23 +++++++++++++++++------
1 file changed, 17 insertions(+), 6 deletions(-)
diff --git a/gcc/tree-ssa-sccvn.cc b/gcc/tree-ssa-sccvn.cc
index 1967bbdca84..16299662b95 100644
--- a/gcc/tree-ssa-sccvn.cc
+++ b/gcc/tree-ssa-sccvn.cc
@@ -6067,6 +6067,9 @@ visit_phi (gimple *phi, bool *inserted, bool
backedges_varying_p)
tree ops[2];
ops[0] = def;
ops[1] = sameval;
+ /* Canonicalize the operands order for eq below. */
+ if (tree_swap_operands_p (ops[0], ops[1]))
+ std::swap (ops[0], ops[1]);
tree val = vn_nary_op_lookup_pieces (2, EQ_EXPR,
boolean_type_node,
ops, &vnresult);
@@ -7905,8 +7908,9 @@ insert_predicates_for_cond (tree_code code, tree lhs,
tree rhs,
if (!true_e && !false_e)
return;
- /* Canonicalize the comparison so the rhs are constants. */
- if (CONSTANT_CLASS_P (lhs))
+ /* Canonicalize the comparison if needed, putting
+ the constant in the rhs. */
+ if (tree_swap_operands_p (lhs, rhs))
{
std::swap (lhs, rhs);
code = swap_tree_comparison (code);
@@ -8145,7 +8149,15 @@ process_bb (rpo_elim &avail, basic_block bb,
{
tree lhs = vn_valueize (gimple_cond_lhs (last));
tree rhs = vn_valueize (gimple_cond_rhs (last));
- tree val = gimple_simplify (gimple_cond_code (last),
+ tree_code cmpcode = gimple_cond_code (last);
+ /* Canonicalize the comparison if needed, putting
+ the constant in the rhs. */
+ if (tree_swap_operands_p (lhs, rhs))
+ {
+ std::swap (lhs, rhs);
+ cmpcode = swap_tree_comparison (cmpcode);
+ }
+ tree val = gimple_simplify (cmpcode,
boolean_type_node, lhs, rhs,
NULL, vn_valueize);
/* If the condition didn't simplfy see if we have recorded
@@ -8156,7 +8168,7 @@ process_bb (rpo_elim &avail, basic_block bb,
tree ops[2];
ops[0] = lhs;
ops[1] = rhs;
- val = vn_nary_op_lookup_pieces (2, gimple_cond_code (last),
+ val = vn_nary_op_lookup_pieces (2, cmpcode,
boolean_type_node, ops,
&vnresult);
/* Got back a ssa name, then try looking up `val != 0`
@@ -8193,14 +8205,13 @@ process_bb (rpo_elim &avail, basic_block bb,
important as early cleanup. */
edge true_e, false_e;
extract_true_false_edges_from_block (bb, &true_e, &false_e);
- enum tree_code code = gimple_cond_code (last);
if ((do_region && bitmap_bit_p (exit_bbs, true_e->dest->index))
|| !can_track_predicate_on_edge (true_e))
true_e = NULL;
if ((do_region && bitmap_bit_p (exit_bbs, false_e->dest->index))
|| !can_track_predicate_on_edge (false_e))
false_e = NULL;
- insert_predicates_for_cond (code, lhs, rhs, true_e, false_e);
+ insert_predicates_for_cond (cmpcode, lhs, rhs, true_e, false_e);
}
break;
}
--
2.43.0
