OpenACC cache directive maintenance.

OpenACC cache directive maintenance.

	gcc/c/
	* c-parser.c (c_parser_oacc_cache): Generate OACC_CACHE.
	* c-typeck.c (c_finish_omp_clauses): Handle OMP_CLAUSE__CACHE_.
	gcc/cp/
	* parser.c (cp_parser_oacc_cache): Generate OACC_CACHE.
	* semantics.c (finish_omp_clauses): Handle OMP_CLAUSE__CACHE_.
	gcc/
	* gimplify.c (gimplify_oacc_cache): New function.
	(gimplify_expr): Use it for OACC_CACHE.
	(gimplify_scan_omp_clauses, gimplify_adjust_omp_clauses): Handle
	OMP_CLAUSE__CACHE_.

	gcc/c/
	* c-parser.c (c_parser_omp_variable_list) <OMP_CLAUSE__CACHE_>:
	Remove explicit mark_exp_read invocations.
	gcc/cp/
	* parser.c (cp_parser_omp_var_list_no_open) <OMP_CLAUSE__CACHE_>:
	Remove explicit mark_exp_read invocations.

	gcc/
	* tree-core.h (enum omp_clause_code): Move OMP_NO_CLAUSE_CACHE
	next to, and handle it like a data clause.  Rename it to
	OMP_CLAUSE__CACHE_.  Update all users.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/branches/gomp-4_0-branch@217146 138bc75d-0d04-0410-961f-82ee72b054a4