Removed all use-cases of Marshal.PtrToStructure in favor of unsafe ptrs.

src/TensorFlowNET.Core/DisposableObject.cs

@@ -54,7 +54,6 @@ namespace Tensorflow
             if (_handle != IntPtr.Zero)
             {
                 DisposeUnmanagedResources(_handle);
-
                 _handle = IntPtr.Zero;
             }
         }

src/TensorFlowNET.Core/Graphs/Graph.Import.cs

@@ -30,11 +30,10 @@ namespace Tensorflow
             var return_output_handle = Marshal.AllocHGlobal(size * num_return_outputs);
 
             c_api.TF_GraphImportGraphDefWithReturnOutputs(_handle, graph_def, opts, return_output_handle, num_return_outputs, s);
-            for (int i = 0; i < num_return_outputs; i++)
-            {
-                var handle = return_output_handle + i * size;
-                return_outputs[i] = Marshal.PtrToStructure<TF_Output>(handle);
-            }
+
+            var tf_output_ptr = (TF_Output*) return_output_handle;
+            for (int i = 0; i < num_return_outputs; i++) 
+                return_outputs[i] = *(tf_output_ptr + i);
 
             Marshal.FreeHGlobal(return_output_handle);
 

src/TensorFlowNET.Core/Graphs/Graph.Operation.cs

@@ -39,16 +39,20 @@ namespace Tensorflow
             return c_api.TF_NewOperation(_handle, opType, opName);
         }
 
-        public unsafe Operation[] ReturnOperations(IntPtr results)
+        public Operation[] ReturnOperations(IntPtr results)
         {
             TF_Operation return_oper_handle = new TF_Operation();
             int num_return_opers = 0;
             c_api.TF_ImportGraphDefResultsReturnOperations(results, ref num_return_opers, ref return_oper_handle);
             Operation[] return_opers = new Operation[num_return_opers];
+            var tf_op_size = Marshal.SizeOf<TF_Operation>();
             for (int i = 0; i < num_return_opers; i++)
             {
-                var handle = return_oper_handle.node + Marshal.SizeOf<TF_Operation>() * i;
-                return_opers[i] = new Operation(*(IntPtr*)handle);
+                unsafe
+                {
+                    var handle = return_oper_handle.node + tf_op_size * i;
+                    return_opers[i] = new Operation(*(IntPtr*)handle);
+                }
             }
 
             return return_opers;

src/TensorFlowNET.Core/Graphs/Graph.cs

@@ -369,7 +369,7 @@ namespace Tensorflow
             var name_key = name.ToLower();
             int i = 0;
             if (_names_in_use.ContainsKey(name_key))
-                i = _names_in_use[name_key];
+                i = _names_in_use[name_key];
             // Increment the number for "name_key".
             if (mark_as_used)
                 _names_in_use[name_key] = i + 1;
@@ -399,13 +399,13 @@ namespace Tensorflow
             int num_return_outputs = 0;
             c_api.TF_ImportGraphDefResultsReturnOutputs(results, ref num_return_outputs, ref return_output_handle);
             TF_Output[] return_outputs = new TF_Output[num_return_outputs];
-            for (int i = 0; i < num_return_outputs; i++)
+            unsafe
             {
-                var handle = return_output_handle + (Marshal.SizeOf<TF_Output>() * i);
-                return_outputs[i] = Marshal.PtrToStructure<TF_Output>(handle);
+                var tf_output_ptr = (TF_Output*) return_output_handle;
+                for (int i = 0; i < num_return_outputs; i++) 
+                    return_outputs[i] = *(tf_output_ptr + i);
+                return return_outputs;
             }
-
-            return return_outputs;
         }
 
         public string[] get_all_collection_keys()

src/TensorFlowNET.Core/Operations/Operation.Output.cs

@@ -50,14 +50,12 @@ namespace Tensorflow
 
         public unsafe TF_Input[] OutputConsumers(int index, int max_consumers)
         {
-            int size = Marshal.SizeOf<TF_Input>();
-            var handle = Marshal.AllocHGlobal(size);
+            var handle = Marshal.AllocHGlobal(Marshal.SizeOf<TF_Input>());
             int num = c_api.TF_OperationOutputConsumers(new TF_Output(_handle, index), handle, max_consumers);
             var consumers = new TF_Input[num];
+            var inputptr = (TF_Input*) handle;
             for (int i = 0; i < num; i++)
-            {
-                consumers[i] = Marshal.PtrToStructure<TF_Input>(handle + i * size);
-            }
+                consumers[i] = *(inputptr + i);
 
             return consumers;
         }

src/TensorFlowNET.Core/Sessions/c_api.tf_session_helper.cs

@@ -27,13 +27,17 @@ namespace Tensorflow
             var handle = Marshal.AllocHGlobal(size * num_consumers);
             int num = TF_OperationOutputConsumers(oper_out, handle, num_consumers);
             var consumers = new string[num_consumers];
-            for (int i = 0; i < num; i++)
+            unsafe
             {
-                TF_Input input = Marshal.PtrToStructure<TF_Input>(handle + i * size);
-                consumers[i] = Marshal.PtrToStringAnsi(TF_OperationName(input.oper));
+                var inputptr = (TF_Input*) handle;
+                for (int i = 0; i < num; i++)
+                {
+                    var oper = (inputptr + i)->oper;
+                    consumers[i] = Marshal.PtrToStringAnsi(TF_OperationName(oper));
+                }
             }
 
             return consumers;
         }
     }
-}
+}