OpenACC 'nohost' clause

OpenACC 'nohost' clause

Do not "compile a version of this procedure for the host".

	gcc/
	* tree-core.h (omp_clause_code): Add 'OMP_CLAUSE_NOHOST'.
	* tree.c (omp_clause_num_ops, omp_clause_code_name, walk_tree_1):
	Handle it.
	* tree-pretty-print.c (dump_omp_clause): Likewise.
	* omp-general.c (oacc_verify_routine_clauses): Likewise.
	* gimplify.c (gimplify_scan_omp_clauses)
	(gimplify_adjust_omp_clauses): Likewise.
	* tree-nested.c (convert_nonlocal_omp_clauses)
	(convert_local_omp_clauses): Likewise.
	* omp-low.c (scan_sharing_clauses): Likewise.
	* omp-offload.c (execute_oacc_device_lower): Update.
	gcc/c-family/
	* c-pragma.h (pragma_omp_clause): Add 'PRAGMA_OACC_CLAUSE_NOHOST'.
	gcc/c/
	* c-parser.c (c_parser_omp_clause_name): Handle 'nohost'.
	(c_parser_oacc_all_clauses): Handle 'PRAGMA_OACC_CLAUSE_NOHOST'.
	(OACC_ROUTINE_CLAUSE_MASK): Add 'PRAGMA_OACC_CLAUSE_NOHOST'.
	* c-typeck.c (c_finish_omp_clauses): Handle 'OMP_CLAUSE_NOHOST'.
	gcc/cp/
	* parser.c (cp_parser_omp_clause_name): Handle 'nohost'.
	(cp_parser_oacc_all_clauses): Handle 'PRAGMA_OACC_CLAUSE_NOHOST'.
	(OACC_ROUTINE_CLAUSE_MASK): Add 'PRAGMA_OACC_CLAUSE_NOHOST'.
	* pt.c (tsubst_omp_clauses): Handle 'OMP_CLAUSE_NOHOST'.
	* semantics.c (finish_omp_clauses): Likewise.
	gcc/fortran/
	* dump-parse-tree.c (show_attr): Update.
	* gfortran.h (symbol_attribute): Add 'oacc_routine_nohost' member.
	(gfc_omp_clauses): Add 'nohost' member.
	* module.c (ab_attribute): Add 'AB_OACC_ROUTINE_NOHOST'.
	(attr_bits, mio_symbol_attribute): Update.
	* openmp.c (omp_mask2): Add 'OMP_CLAUSE_NOHOST'.
	(gfc_match_omp_clauses): Handle 'OMP_CLAUSE_NOHOST'.
	(OACC_ROUTINE_CLAUSES): Add 'OMP_CLAUSE_NOHOST'.
	(gfc_match_oacc_routine): Update.
	* trans-decl.c (add_attributes_to_decl): Update.
	* trans-openmp.c (gfc_trans_omp_clauses): Likewise.
	gcc/testsuite/
	* c-c++-common/goacc/classify-routine-nohost.c: New file.
	* c-c++-common/goacc/classify-routine.c: Update.
	* c-c++-common/goacc/routine-2.c: Likewise.
	* c-c++-common/goacc/routine-nohost-1.c: New file.
	* c-c++-common/goacc/routine-nohost-2.c: Likewise.
	* g++.dg/goacc/template.C: Update.
	* gfortran.dg/goacc/classify-routine-nohost.f95: New file.
	* gfortran.dg/goacc/classify-routine.f95: Update.
	* gfortran.dg/goacc/pure-elemental-procedures-2.f90: Likewise.
	* gfortran.dg/goacc/routine-6.f90: Likewise.
	* gfortran.dg/goacc/routine-intrinsic-2.f: Likewise.
	* gfortran.dg/goacc/routine-module-1.f90: Likewise.
	* gfortran.dg/goacc/routine-module-2.f90: Likewise.
	* gfortran.dg/goacc/routine-module-3.f90: Likewise.
	* gfortran.dg/goacc/routine-module-mod-1.f90: Likewise.
	* gfortran.dg/goacc/routine-multiple-directives-1.f90: Likewise.
	* gfortran.dg/goacc/routine-multiple-directives-2.f90: Likewise.
	libgomp/
	* testsuite/libgomp.oacc-c-c++-common/routine-nohost-1.c: New
	file.
	* testsuite/libgomp.oacc-c-c++-common/routine-nohost-2.c:
	Likewise.
	* testsuite/libgomp.oacc-c-c++-common/routine-nohost-2_2.c:
	Likewise.
	* testsuite/libgomp.oacc-fortran/routine-nohost-1.f90: Likewise.

Co-Authored-By: Joseph Myers <joseph@codesourcery.com>
Co-Authored-By: Cesar Philippidis <cesar@codesourcery.com>