[OPENMP] Codegen for 'ordered' directive.

Add codegen for 'ordered' directive:

__kmpc_ordered(ident_t *, gtid);
<associated statement>;
__kmpc_end_ordered(ident_t *, gtid);
Also for 'for' directives with the dynamic scheduling and an 'ordered' clause added a call to '__kmpc_dispatch_fini_(4|8)[u]()' function after increment expression for loop control variable:

while(__kmpc_dispatch_next(&LB, &UB)) {
  idx = LB;
  while (idx <= UB) { BODY; ++idx;
    __kmpc_dispatch_fini_(4|8)[u](); // For ordered loops only.
  } // inner loop
}
Differential Revision: http://reviews.llvm.org/D9070

llvm-svn: 235496

clang/lib/CodeGen/CodeGenFunction.h

@@ -2139,10 +2139,21 @@ public:
   void EmitOMPTargetDirective(const OMPTargetDirective &S);
   void EmitOMPTeamsDirective(const OMPTeamsDirective &S);
 
-  void
-  EmitOMPInnerLoop(const Stmt &S, bool RequiresCleanup, const Expr *LoopCond,
-                   const Expr *IncExpr,
-                   const llvm::function_ref<void(CodeGenFunction &)> &BodyGen);
+  /// \brief Emit inner loop of the worksharing/simd construct.
+  ///
+  /// \param S Directive, for which the inner loop must be emitted.
+  /// \param RequiresCleanup true, if directive has some associated private
+  /// variables.
+  /// \param LoopCond Bollean condition for loop continuation.
+  /// \param IncExpr Increment expression for loop control variable.
+  /// \param BodyGen Generator for the inner body of the inner loop.
+  /// \param PostIncGen Genrator for post-increment code (required for ordered
+  /// loop directvies).
+  void EmitOMPInnerLoop(
+      const Stmt &S, bool RequiresCleanup, const Expr *LoopCond,
+      const Expr *IncExpr,
+      const llvm::function_ref<void(CodeGenFunction &)> &BodyGen,
+      const llvm::function_ref<void(CodeGenFunction &)> &PostIncGen);
 
 private: