2018-06-20  Martin Liska  <mliska@suse.cz>

	* tree-switch-conversion.c (jump_table_cluster::find_jump_tables):
        New.
	(bit_test_cluster::find_bit_tests): Likewise.
	(switch_decision_tree::analyze_switch_statement): Find clusters.
	* tree-switch-conversion.h (struct jump_table_cluster): Document
        hierarchy.

From-SVN: r261794