* gimple-pretty-print.c (dump_ssaname_info): Print newline also
	in case of VR_VARYING.  Print get_nonzero_bits if not all ones.
	* tree-ssanames.h (struct range_info_def): Add nonzero_bits field.
	(set_nonzero_bits, get_nonzero_bits): New prototypes.
	* tree-ssa-ccp.c (get_default_value): Use get_range_info to see if
	a default def isn't partially constant.
	(ccp_finalize): If after IPA, set_range_info if integral SSA_NAME
	is known to be partially zero.
	(evaluate_stmt): If we'd return otherwise VARYING, use get_range_info
	to see if a default def isn't partially constant.
	* tree-ssanames.c (set_range_info): Initialize nonzero_bits upon
	creation of a range, if VR_RANGE, try to improve nonzero_bits from
	the range.
	(set_nonzero_bits, get_nonzero_bits): New functions.

	* g++.dg/warn/pr33738.C (main): Initialize a2 again to make sure
	we warn about it already during VRP1 pass.

From-SVN: r204256