re PR rtl-optimization/82044 (runtime signed integer overflow in check_mem_read_rtx() and all_positions_needed_p() in dse.c)

	PR rtl-optimization/82044
	PR tree-optimization/82042
	* dse.c (record_store): Check for overflow.
	(check_mem_read_rtx): Properly check for overflow if width == -1, call
	add_wild_read instead of clear_rhs_from_active_local_stores on
	overflow and log it into dump_file.

From-SVN: r255048