* lib/target-supports.exp
	(check_effective_target_logical_op_short_circuit): New procedure.
	* gcc.dg/binop-xor1.c: XFAIL for logical_op_short_circuit.
	* gcc.dg/tree-ssa/forwprop-28.c: Use logical_op_short_circuit
	instead of mips*-*-*, arc*-*-*, avr*-*-* and arm_cortex_m tests.
	* gcc.dg/tree-ssa/vrp47.c: Likewise.
	* gcc.dg/tree-ssa/vrp87.c: Likewise.
	* gcc.dg/tree-ssa/ssa-dom-thread-4.c: Likewise.  Also use
	logical_op_short_circuit for the alternative test, extending
	it to arm_cortex_m.

From-SVN: r207810