Disable caching when node has state. (#3043)

* Disable caching when node has state.

* Address PR feedback: move has_state to Node.

* Address PR feedback.

* Fix style error.

src/ngraph/node.hpp

@@ -216,6 +216,7 @@ namespace ngraph
         virtual bool is_op() const { return false; }
         virtual bool is_commutative() { return false; }
         virtual bool is_dynamic() const;
+        virtual bool has_state() const { return false; }
         size_t get_instance_id() const { return m_instance_id; }
         friend std::ostream& operator<<(std::ostream&, const Node&);
         virtual std::ostream& write_short_description(std::ostream&) const;

src/ngraph/op/experimental/generate_mask.hpp

@@ -72,6 +72,8 @@ namespace ngraph
             /// \brief Returns the seed value supplied to a random generator
             uint64_t get_seed() const { return m_seed; }
             bool get_use_seed() const { return m_use_seed; }
+            /// GenerateMask has state.
+            bool has_state() const override { return true; }
         protected:
             virtual void generate_adjoints(autodiff::Adjoints& adjoints,
                                            const NodeVector& deltas) override

src/ngraph/runtime/cpu/cpu_external_function.cpp

@@ -924,7 +924,8 @@ using namespace ngraph::runtime;
             // Always enable nodes computing output tensors or nodes whose outputs might get
             // overwritten due to inplace kernels
             // TODO (jbobba) - Do we need to handle cacheability
-            if (computes_result(node.get()) || possibly_overwritten(node.get()))
+            if (computes_result(node.get()) || possibly_overwritten(node.get()) ||
+                node->has_state())
             {
                 writer << " || 1";
             }
@@ -1423,7 +1424,7 @@ void runtime::cpu::CPU_ExternalFunction::build(ngraph::pass::PassConfig& pass_co
         bool disable_caching =
             (reuse_memory &&
              !cacheable) // Check cacheability only if we are reusing intermediate tensors
-            || computes_result(node.get()) || possibly_overwritten(node.get());
+            || computes_result(node.get()) || possibly_overwritten(node.get()) || node->has_state();
 
         vector<reference_wrapper<bool>> in_stale, out_stale;
         for (const auto& name : in_names)