* sbitmap.c (bitmap_bit_in_range_p): New function.
	* sbitmap.h (bitmap_bit_in_range_p): Prototype.
	* tree-ssa-dse.c (live_bytes_read): New function.
	(dse_classify_store): Ignore reads of dead bytes.

	* testsuite/gcc.dg/tree-ssa/ssa-dse-26.c: New test.

From-SVN: r253305