if (is_op_commutative(get_irn_op(n))) {
ir_node *l = get_binop_left(n);
ir_node *r = get_binop_right(n);
-
- /* for commutative operators perform a OP b == b OP a */
- if (l > r) {
+ int l_idx = get_irn_idx(l);
+ int r_idx = get_irn_idx(r);
+
+ /* For commutative operators perform a OP b == b OP a but keep
+ constants on the RIGHT side. This helps greatly in some optimizations.
+ Moreover we use the idx number to make the form deterministic. */
+ if (is_irn_constlike(l))
+ l_idx = -l_idx;
+ if (is_irn_constlike(r))
+ r_idx = -r_idx;
+ if (l_idx < r_idx) {
set_binop_left(n, r);
set_binop_right(n, l);
}
}
/* lookup or insert in hash table with given hash key. */
- o = pset_insert (value_table, n, ir_node_hash (n));
+ o = pset_insert(value_table, n, ir_node_hash(n));
if (o != n) {
DBG_OPT_CSE(n, o);