The following plugs one hole where we require a VEC_PERM node representative unnecessarily. This is for vect_check_store_rhs which looks at the RHS and checks whether a constant can be native encoded. The fix is to guard that with vect_constant_def additionally and making vect_is_simple_use forgiving for a missing SLP_TREE_REPRESENTATIVE when the child is a VEC_PERM node, initializing the scalar def to error_mark_node.
* tree-vect-stmts.cc (vect_check_store_rhs): Look at *rhs only when it's a vec_constant_def. (vect_is_simple_use): When we have no representative for an internal node, fill in *op with error_mark_node. --- gcc/tree-vect-stmts.cc | 25 ++++++++++++++++++++++--- 1 file changed, 22 insertions(+), 3 deletions(-) diff --git a/gcc/tree-vect-stmts.cc b/gcc/tree-vect-stmts.cc index 672959501bb..4219ad832db 100644 --- a/gcc/tree-vect-stmts.cc +++ b/gcc/tree-vect-stmts.cc @@ -2553,7 +2553,8 @@ vect_check_store_rhs (vec_info *vinfo, stmt_vec_info stmt_info, /* In the case this is a store from a constant make sure native_encode_expr can handle it. */ - if (CONSTANT_CLASS_P (*rhs) && native_encode_expr (*rhs, NULL, 64) == 0) + if (rhs_dt == vect_constant_def + && CONSTANT_CLASS_P (*rhs) && native_encode_expr (*rhs, NULL, 64) == 0) { if (dump_enabled_p ()) dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location, @@ -14002,8 +14003,26 @@ vect_is_simple_use (vec_info *vinfo, stmt_vec_info stmt, slp_tree slp_node, *vectype = SLP_TREE_VECTYPE (child); if (SLP_TREE_DEF_TYPE (child) == vect_internal_def) { - *op = gimple_get_lhs (SLP_TREE_REPRESENTATIVE (child)->stmt); - return vect_is_simple_use (*op, vinfo, dt, def_stmt_info_out); + /* ??? VEC_PERM nodes might be intermediate and their lane value + have no representative (nor do we build a VEC_PERM stmt for + the actual operation). Note for two-operator nodes we set + a representative but leave scalar stmts empty as we'd only + have one for a subset of lanes. Ideally no caller would + require *op for internal defs. */ + if (SLP_TREE_REPRESENTATIVE (child)) + { + *op = gimple_get_lhs (SLP_TREE_REPRESENTATIVE (child)->stmt); + return vect_is_simple_use (*op, vinfo, dt, def_stmt_info_out); + } + else + { + gcc_assert (SLP_TREE_CODE (child) == VEC_PERM_EXPR); + *op = error_mark_node; + *dt = vect_internal_def; + if (def_stmt_info_out) + *def_stmt_info_out = NULL; + return true; + } } else { -- 2.35.3