PR tree-optimization/45216
	PR tree-optimization/57157
	* tree-ssa-forwprop.c (simplify_rotate): New function.
	(ssa_forward_propagate_and_combine): Call it.

	* c-c++-common/rotate-1.c: New test.
	* c-c++-common/rotate-1a.c: New test.
	* c-c++-common/rotate-2.c: New test.
	* c-c++-common/rotate-2a.c: New test.
	* c-c++-common/rotate-3.c: New test.
	* c-c++-common/rotate-3a.c: New test.
	* c-c++-common/rotate-4.c: New test.
	* c-c++-common/rotate-4a.c: New test.

From-SVN: r198769