OpenMP offloading to NVPTX: middle-end changes

OpenMP offloading to NVPTX: middle-end changes

	* internal-fn.c (expand_GOMP_SIMT_LANE): New.
	(expand_GOMP_SIMT_VF): New.
	(expand_GOMP_SIMT_LAST_LANE): New.
	(expand_GOMP_SIMT_ORDERED_PRED): New.
	(expand_GOMP_SIMT_VOTE_ANY): New.
	(expand_GOMP_SIMT_XCHG_BFLY): New.
	(expand_GOMP_SIMT_XCHG_IDX): New.
	* internal-fn.def (GOMP_SIMT_LANE): New.
	(GOMP_SIMT_VF): New.
	(GOMP_SIMT_LAST_LANE): New.
	(GOMP_SIMT_ORDERED_PRED): New.
	(GOMP_SIMT_VOTE_ANY): New.
	(GOMP_SIMT_XCHG_BFLY): New.
	(GOMP_SIMT_XCHG_IDX): New.
	* omp-low.c (omp_maybe_offloaded_ctx): New, outlined from...
	(create_omp_child_function): ...here.  Set "omp target entrypoint"
	or "omp declare target" attribute based on is_gimple_omp_offloaded.
	(omp_max_simt_vf): New.  Use it...
	(omp_max_vf): ...here.
	(lower_rec_input_clauses): Add reduction lowering for SIMT execution.
	(lower_lastprivate_clauses): Likewise, for "lastprivate" lowering.
	(lower_omp_ordered): Likewise, for "ordered" lowering.
	(expand_omp_simd): Add SIMT transforms.
	(pass_data_lower_omp): Add PROP_gimple_lomp_dev.
	(execute_omp_device_lower): New.
	(pass_data_omp_device_lower): New.
	(pass_omp_device_lower): New pass.
	(make_pass_omp_device_lower): New.
	* passes.def (pass_omp_device_lower): Position new pass.
	* tree-pass.h (PROP_gimple_lomp_dev): Define.
	(make_pass_omp_device_lower): Declare.

From-SVN: r242710