PR ipa/79764
(chkp_narrow_size_and_offset): New function.
(chkp_parse_array_and_component_ref): Support BIT_FIELD_REF.
(void chkp_parse_bit_field_ref): New function.
(chkp_make_addressed_object_bounds): Add case for BIT_FIELD_REF.
(chkp_process_stmt): Use chkp_parse_bit_field_ref.
2017-03-09 Martin Liska <mliska@suse.cz>