PR tree-optimization/70754
	* tree-predcom.c (stmt_combining_refs): New parameter INSERT_BEFORE.
	(reassociate_to_the_same_stmt): New parameter INSERT_BEFORE.  Insert
	combined stmt before it if not NULL.
	(combine_chains): Process refs reversely and compute dominance point
	for root ref.

	gcc/testsuite
	PR tree-optimization/70754
	* gfortran.dg/pr70754.f90: New test.

From-SVN: r244815