2018-02-12  Richard Sandiford  <richard.sandiford@linaro.org>

gcc/
	PR tree-optimization/84321
	* tree-vrp.c (intersect_range_with_nonzero_bits): Fix VR_ANTI_RANGE
	handling.  Also check whether the anti-range contains any values
	that satisfy the mask; switch to a VR_RANGE if not.

gcc/testsuite/
	PR tree-optimization/84321
	* gcc.dg/pr84321.c: New test.

From-SVN: r257629