Add pass_ch_oacc_kernels to pass_oacc_kernels

Add pass_ch_oacc_kernels to pass_oacc_kernels

	gcc/
	* omp-low.c (loop_in_oacc_kernels_region_p): New function.
	* omp-low.h (loop_in_oacc_kernels_region_p): Declare.
	* passes.def: Add pass_ch_oacc_kernels to pass group pass_oacc_kernels.
	* tree-pass.h (make_pass_ch_oacc_kernels): Declare
	* tree-ssa-loop-ch.c: Include omp-low.h.
	(pass_ch_execute): Declare.
	(pass_ch::execute): Factor out ...
	(pass_ch_execute): ... this new function.  If handling oacc kernels,
	skip loops that are not in oacc kernels region.
	(pass_ch_oacc_kernels::execute):
	(pass_data_ch_oacc_kernels): New pass_data.
	(class pass_ch_oacc_kernels): New pass.
	(pass_ch_oacc_kernels::execute, make_pass_ch_oacc_kernels): New
	function.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/gomp-4_0-branch@222281 138bc75d-0d04-0410-961f-82ee72b054a4