[OPENMP50]Add support for 'parallel master taskloop' construct.

Added parsing/sema/codegen support for 'parallel master taskloop'
constructs. Some of the clauses, like 'grainsize', 'num_tasks', 'final'
and 'priority' are not supported in full, only constant expressions can
be used currently in these clauses.

llvm-svn: 374791
diff --git a/clang/lib/Serialization/ASTWriterStmt.cpp b/clang/lib/Serialization/ASTWriterStmt.cpp
index 7cf4ab8..387ed44 100644
--- a/clang/lib/Serialization/ASTWriterStmt.cpp
+++ b/clang/lib/Serialization/ASTWriterStmt.cpp
@@ -2229,6 +2229,12 @@
   Code = serialization::STMT_OMP_MASTER_TASKLOOP_DIRECTIVE;
 }
 
+void ASTStmtWriter::VisitOMPParallelMasterTaskLoopDirective(
+    OMPParallelMasterTaskLoopDirective *D) {
+  VisitOMPLoopDirective(D);
+  Code = serialization::STMT_OMP_PARALLEL_MASTER_TASKLOOP_DIRECTIVE;
+}
+
 void ASTStmtWriter::VisitOMPDistributeDirective(OMPDistributeDirective *D) {
   VisitOMPLoopDirective(D);
   Code = serialization::STMT_OMP_DISTRIBUTE_DIRECTIVE;