* tree-nested.c (convert_nonlocal_omp_clauses,
	convert_local_omp_clauses): Handle OMP_CLAUSE_IN_REDUCTION,
	OMP_CLAUSE_TASK_REDUCTION and OMP_CLAUSE__SIMT_ clauses.
	(convert_nonlocal_reference_stmt, convert_local_reference_stmt):
	Convert clauses for GIMPLE_OMP_TASKGROUP.

	* testsuite/libgomp.c/task-reduction-3.c: New test.

From-SVN: r266723