re PR tree-optimization/46969 (-fcompare-debug failure with -O -ftree-vectorize -ftree-parallelize-loops=2)

	PR tree-optimization/46969
	* tree-parloops.c (struct reduction_info): Add reduc_version.
	(reduction_info_hash): Return reduc_version field.
	(reduction_phi): Set reduc_version to gimple_uid (phi).
	(build_new_reduction): Set reduc_version to SSA_NAME_VERSION of
	phi result.
	(set_reduc_phi_uids): New function.
	(gather_scalar_reductions): Call it at the end through htab_traverse.

	* gcc.dg/autopar/pr46969.c: New test.

From-SVN: r168034