re PR tree-optimization/71488 (Wrong code for vector comparisons with ivybridge and westmere targets)

gcc/

	PR middle-end/71488
	* tree-vect-patterns.c (vect_recog_mask_conversion_pattern): Support
	comparison of boolean vectors.
	* tree-vect-stmts.c (vectorizable_comparison): Vectorize comparison
	of boolean vectors using bitwise operations.

gcc/testsuite/

	PR middle-end/71488
	* g++.dg/pr71488.C: New test.
	* gcc.dg/vect/vect-bool-cmp.c: New test.

From-SVN: r237706