re PR tree-optimization/46939 (http://blog.regehr.org/archives/320 example 6)

	PR middle-end/46939
	* predic.c (predict_paths_leading_to_edge): New function.
	(apply_return_prediction): Use it.
	(predict_paths_for_bb): Do not special case abnormals.
	* gcc.target/i386/pr46939.c: New testcase.

From-SVN: r167893