* genrecog.c (decision_test.u.insn): Add `lineno'.
(pattern_lineno, error_count): New variables.
(message_with_line): New.
(add_to_sequence): Break out checking code to ...
(validate_pattern): ... here. Detect SET_DEST matching CONST_INT.
(merge_insn): Use message_with_line.
(make_insn_sequence): Use validate_pattern. Record insn lineno.
(main): Set read_rtx_filename, pattern_lineno. Exit early on error.