PR tree-optimization/31739
* tree-vrp.c (vrp_val_is_max): New static function.
(vrp_val_is_min): New static function.
(set_value_range_to_value): Use TYPE_{MAX,MIN}_VALUE rather than
copying the node.
(set_value_range): Use vrp_val_is_{max,min}.
(extract_range_from_assert): Likewise.
(extract_range_from_binary_expr): Likewise.
(extract_range_from_unary_expr): Likewise.
(dump_value_range, vrp_meet): Likewise.
(vrp_visit_phi_node): Likewise.
* tree.c (build_distinct_type_copy): Revert change of 2007-04-27.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@124334 138bc75d-0d04-0410-961f-82ee72b054a4