re PR middle-end/35897 (DSE doesn't support targets with wide registers)

re PR middle-end/35897 (DSE doesn't support targets with wide registers)

2008-04-11  H.J. Lu  <hongjiu.lu@intel.com>

	PR middle-end/35897
	* dse.c (store_info): Change positions_needed to unsigned
	HOST_WIDE_INT.
	(lowpart_bitmask): New.
	(record_store): Cast to unsigned HOST_WIDE_INT for
	positions_needed.  Assert width <= size of positions_needed *
	CHAR_BIT.  Call lowpart_bitmask to initialize positions_needed.
	(check_mem_read_rtx): Use unsigned HOST_WIDE_INT on mask.  Call
	lowpart_bitmask to set mask.

From-SVN: r134199