lower-subreg.c (enum classify_move_insn): Rename SIMPLE_PSEUDO_REG_MOVE to DECOMPOSABLE_SIMPLE_MOVE.

ChangeLog:

	* lower-subreg.c (enum classify_move_insn): Rename
	SIMPLE_PSEUDO_REG_MOVE to DECOMPOSABLE_SIMPLE_MOVE.
	(find_decomposable_subregs): Update.
	(decompose_multiword_subregs): Add DECOMPOSE_COPIES parameter.
	Only mark pseudo-to-pseudo copies as DECOMPOSABLE_SIMPLE_MOVE
	if that parameter is true.
	(rest_of_handle_lower_subreg): Call decompose_multiword_subregs
	with DECOMPOSE_COPIES false.
	(rest_of_handle_lower_subreg2): Call decompose_multiword_subregs
	with DECOMPOSE_COPIES true.

testsuite/ChangeLog:

	* gcc.dg/lower-subreg-1.c: Disable on arm-*-* targets.

From-SVN: r191805