* tree.def (MULT_HIGHPART_EXPR): New.
        * cfgexpand.c (expand_debug_expr): Ignore it.
        * expr.c (expand_expr_real_2): Handle it.
        * fold-const.c (int_const_binop_1): Likewise.
        * optabs.c (optab_for_tree_code): Likewise.
        * tree-cfg.c (verify_gimple_assign_binary): Likewise.
        * tree-inline.c (estimate_operator_cost): Likewise.
        * tree-pretty-print.c (dump_generic_node): Likewise.
        (op_code_prio, op_symbol_code): Likewise.
        * tree.c (commutative_tree_code): Likewise.  Also handle
        WIDEN_MULT_EXPR, VEC_WIDEN_MULT_HI_EXPR, VEC_WIDEN_MULT_LO_EXPR.

From-SVN: r189027