* gimple.h (gimple_build_switch): Remove.
	(gimple_build_switch_vec): Promote to the new gimple_build_switch.
	(gimple_switch_default_label): Assert the default case label is
	really a default case label.
	(gimple_switch_set_default_label): Likewise.
	* gimple.c (gimple_build_switch_nlabels): Make sure a default label
	is passed in, and simplify accordingly.
	(gimple_build_switch): Removed.
	(gimple_build_switch_vec): Rename to gimple_build_switch.
	* gimplify.c (gimplify_switch_expr): Update gimple_build_switch use.
	* gimple-pretty-print.c (dump_gimple_switch): Do not accept a NULL
	case label.
	* stmt.c (expand_case): Simplify using the fact that every GIMPLE
	switch must have a default case.
	* tree-cfg.c (group_case_labels_stmt): Likewise.
	(verify_gimple_switch): Use gimple_switch_label in verifier to get
	the label at index 0, and verify that it is a valid default case.
	* except.c (sjlj_emit_dispatch_table): Rewrite construction of the
	switch for dispatching.
	* tree-eh.c (lower_try_finally_switch): Update gimple_build_switch use.
	(lower_eh_dispatch): Likewise.
	* tree-vrp.c (execute_vrp): Use gimple_switch_label to get the case
	label at index 0 before turning it into a default case label.
	* omp-low.c (expand_omp_sections): Update gimple_build_switch use.
	* tree-switch-conversion.c (emit_case_bit_tests): Get the default case
	label using gimple_switch_default_label.
	(collect_switch_conv_info): Likewise.
	(process_switch): Likewise.
	* doc/gimple.texi: Update documentation of gimple_build_switch.

From-SVN: r190925