#113

src/TensorFlowNET.Core/APIs/c_api.cs

@@ -27,7 +27,7 @@ namespace Tensorflow
     /// string => IntPtr c_api.StringPiece(IntPtr)
     /// unsigned char => byte
     /// </summary>
-    public static partial class c_api
+    public partial class c_api
     {
         public const string TensorFlowLibName = "tensorflow";
 

src/TensorFlowNET.Core/Attributes/c_api.ops.cs

@@ -5,7 +5,7 @@ using System.Text;
 
 namespace Tensorflow
 {
-    public static partial class c_api
+    public partial class c_api
     {
         /// <summary>
         /// Fills in `value` with the value of the attribute `attr_name`.  `value` must

src/TensorFlowNET.Core/Buffers/c_api.buffer.cs

@@ -5,7 +5,7 @@ using System.Text;
 
 namespace Tensorflow
 {
-    public static partial class c_api
+    public partial class c_api
     {
         [DllImport(TensorFlowLibName)]
         public static extern void TF_DeleteBuffer(IntPtr buffer);

src/TensorFlowNET.Core/Functions/c_api.function.cs

@@ -5,7 +5,7 @@ using System.Text;
 
 namespace Tensorflow
 {
-    public static partial class c_api
+    public partial class c_api
     {
         /// <summary>
         /// Write out a serialized representation of `func` (as a FunctionDef protocol

src/TensorFlowNET.Core/Gradients/c_api.gradient.cs

@@ -5,7 +5,7 @@ using System.Text;
 
 namespace Tensorflow
 {
-    public static partial class c_api
+    public partial class c_api
     {
         /// <summary>
         /// Adds operations to compute the partial derivatives of sum of `y`s w.r.t `x`s,

src/TensorFlowNET.Core/Gradients/gradients_impl.py.cs

@@ -53,10 +53,76 @@ namespace Tensorflow
             using (var namescope = new ops.name_scope<Tensor>(name, "gradients", values: all))
             {
                 grad_scope = namescope;
+                // Get a uid for this call to gradients that can be used to help
+                // cluster ops for compilation.
+                var gradient_uid = ops.get_default_graph().unique_name("uid");
 
+                var to_ops = ys1.Select(x => x.op).ToList();
+                var from_ops = xs1.Select(x => x.op).ToList();
+                var stop_gradient_ops = stop_gradients1.Select(x => x.op).ToList();
+                _PendingCount(to_ops, from_ops, colocate_gradients_with_ops, new List<object>(), xs1);
             }
         }
 
+        /// <summary>
+        /// 
+        /// </summary>
+        /// <param name="grad_ys"></param>
+        /// <param name="ys"></param>
+        /// <param name="colocate_gradients_with_ops"></param>
+        /// <param name="gradient_uid"></param>
+        private void _DefaultGradYs(List<Tensor> grad_ys, List<Tensor> ys, bool colocate_gradients_with_ops, string gradient_uid = "__unsupported__")
+        {
+
+        }
+
+        /// <summary>
+        /// Initialize the pending count for ops between two lists of Operations.
+        /// 'pending_count[op]' indicates the number of backprop inputs
+        /// to this operation.
+        /// </summary>
+        /// <param name="to_ops"></param>
+        /// <param name="from_ops"></param>
+        /// <param name="colocate_gradients_with_ops"></param>
+        /// <param name="func_graphs"></param>
+        /// <param name="xs"></param>
+        private static void _PendingCount(List<Operation> to_ops, List<Operation> from_ops, bool colocate_gradients_with_ops, List<object> func_graphs, List<Tensor> xs)
+        {
+            List<Operation> reached_ops = new List<Operation>();
+            _MarkReachedOps(from_ops, reached_ops, func_graphs);
+        }
+
+        /// <summary>
+        /// Mark all ops reached from "from_ops"
+        /// </summary>
+        /// <param name="from_ops"></param>
+        /// <param name="reached_ops"></param>
+        /// <param name="func_graphs"></param>
+        private static void _MarkReachedOps(List<Operation> from_ops, List<Operation> reached_ops, List<object> func_graphs)
+        {
+            foreach(var op in from_ops)
+            {
+                reached_ops.Add(op);
+                foreach(var output in op.outputs)
+                {
+                    reached_ops.AddRange(_Consumers(output, func_graphs));
+                }
+            }
+
+            reached_ops.Reverse();
+        }
+
+        /// <summary>
+        /// Returns the consumers of t, crossing closure boundaries where necessary.
+        /// </summary>
+        /// <param name="t"></param>
+        /// <param name="func_graphs"></param>
+        private static List<Operation> _Consumers(Tensor t, List<object> func_graphs)
+        {
+            var consumers = t.consumers();
+            return consumers;
+        }
+
         private static List<Tensor> _AsList(object ys)
         {
             List<Tensor> ret = null;

src/TensorFlowNET.Core/Graphs/c_api.graph.cs

@@ -5,7 +5,7 @@ using System.Text;
 
 namespace Tensorflow
 {
-    public static partial class c_api
+    public partial class c_api
     {
         /// <summary>
         /// Destroy an options object.  Graph will be deleted once no more

src/TensorFlowNET.Core/Operations/Operation.cs

@@ -32,12 +32,12 @@ namespace Tensorflow
         public unsafe TF_Input[] OutputConsumers(int index, int max_consumers)
         {
             int size = Marshal.SizeOf<TF_Input>();
-            var handle = (TF_Input*)Marshal.AllocHGlobal(size);
+            var handle = Marshal.AllocHGlobal(size);
             int num = c_api.TF_OperationOutputConsumers(new TF_Output(_handle, index), handle, max_consumers);
             var consumers = new TF_Input[num];
             for(int i = 0; i < num; i++)
             {
-                consumers[i] = new TF_Input((*handle).oper + i * size, (*handle).index);
+                consumers[i] = Marshal.PtrToStructure<TF_Input>(handle + i * size);
             }
 
             return consumers;
@@ -161,6 +161,11 @@ namespace Tensorflow
             }
         }
 
+        public override string ToString()
+        {
+            return $"'{Name}' type={OpType}";
+        }
+
         public static implicit operator Operation(IntPtr handle) => new Operation(handle);
         public static implicit operator IntPtr(Operation op) => op._handle;
 

src/TensorFlowNET.Core/Operations/c_api.ops.cs

@@ -5,7 +5,7 @@ using System.Text;
 
 namespace Tensorflow
 {
-    public static partial class c_api
+    public partial class c_api
     {
         /// <summary>
         /// Request that `desc` be co-located on the device where `op`
@@ -154,12 +154,15 @@ namespace Tensorflow
         /// an operation.  Returns the number of output consumers (should match
         /// TF_OperationOutputNumConsumers(oper_out)).
         /// </summary>
-        /// <param name="oper_out"></param>
-        /// <param name="consumers"></param>
-        /// <param name="max_consumers"></param>
+        /// <param name="oper_out">TF_Output</param>
+        /// <param name="consumers">TF_Input*</param>
+        /// <param name="max_consumers">int</param>
         /// <returns></returns>
         [DllImport(TensorFlowLibName)]
-        public static extern unsafe int TF_OperationOutputConsumers(TF_Output oper_out, TF_Input* consumers, int max_consumers);
+        public static extern unsafe int TF_OperationOutputConsumers(TF_Output oper_out, IntPtr consumers, int max_consumers);
+
+        [DllImport(TensorFlowLibName)]
+        public static extern int TF_OperationOutputConsumers(TF_Output oper_out);
 
         [DllImport(TensorFlowLibName)]
         public static extern TF_DataType TF_OperationOutputType(TF_Output oper_out);

src/TensorFlowNET.Core/Operations/gen_array_ops.cs

@@ -26,5 +26,20 @@ namespace Tensorflow
 
             return new Tensor(_op, 0, dtype);
         }
+
+        /// <summary>
+        /// Return a tensor with the same shape and contents as the input tensor or value.
+        /// </summary>
+        /// <param name="input"></param>
+        /// <param name="name"></param>
+        public static Tensor identity(Tensor input, string name = "")
+        {
+            var keywords = new Dictionary<string, object>();
+            keywords.Add("input", input);
+
+            var _op = _op_def_lib._apply_op_helper("Identity", name, keywords);
+
+            return _op.outputs[0];
+        }
     }
 }

src/TensorFlowNET.Core/Operations/gen_math_ops.cs

@@ -16,7 +16,7 @@ namespace Tensorflow
             keywords.Add("x", x);
             keywords.Add("y", y);
 
-            var _op = _op_def_lib._apply_op_helper("Add", name: "add", keywords: keywords);
+            var _op = _op_def_lib._apply_op_helper("Add", keywords: keywords);
 
             return new Tensor(_op, 0, _op.OutputType(0));
         }
@@ -38,7 +38,7 @@ namespace Tensorflow
             keywords.Add("x", x);
             keywords.Add("y", y);
 
-            var _op = _op_def_lib._apply_op_helper("Mul", name: "mul", keywords: keywords);
+            var _op = _op_def_lib._apply_op_helper("Mul", keywords: keywords);
 
             return new Tensor(_op, 0, _op.OutputType(0));
         }
@@ -62,7 +62,7 @@ namespace Tensorflow
             keywords.Add("transpose_a", transpose_a);
             keywords.Add("transpose_b", transpose_b);
 
-            var _op = _op_def_lib._apply_op_helper("MatMul", name: "MatMul", keywords: keywords);
+            var _op = _op_def_lib._apply_op_helper("MatMul", keywords: keywords);
 
             return new Tensor(_op, 0, _op.OutputType(0));
         }
@@ -73,7 +73,7 @@ namespace Tensorflow
             keywords.Add("x", x);
             keywords.Add("y", y);
 
-            var _op = _op_def_lib._apply_op_helper("Pow", name: "Pow", keywords: keywords);
+            var _op = _op_def_lib._apply_op_helper("Pow", keywords: keywords);
 
             return new Tensor(_op, 0, _op.OutputType(0));
         }

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

@@ -5,7 +5,7 @@ using System.Text;
 
 namespace Tensorflow
 {
-    public static partial class c_api
+    public partial class c_api
     {
         /// <summary>
         /// Destroy a session object.

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

@@ -0,0 +1,26 @@
+using System;
+using System.Collections.Generic;
+using System.Runtime.InteropServices;
+using System.Text;
+
+namespace Tensorflow
+{
+    public partial class c_api
+    {
+        public static string[] TF_OperationOutputConsumers_wrapper(TF_Output oper_out)
+        {
+            int num_consumers = TF_OperationOutputConsumers(oper_out);
+            int size = Marshal.SizeOf<TF_Input>();
+            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++)
+            {
+                TF_Input input = Marshal.PtrToStructure<TF_Input>(handle + i * size);
+                consumers[i] = Marshal.PtrToStringAnsi(TF_OperationName(input.oper));
+            }
+
+            return consumers;
+        }
+    }
+}

src/TensorFlowNET.Core/Status/c_api.status.cs

@@ -5,7 +5,7 @@ using System.Text;
 
 namespace Tensorflow
 {
-    public static partial class c_api
+    public partial class c_api
     {
         /// <summary>
         /// Delete a previously created status object.

src/TensorFlowNET.Core/Tensors/Tensor.cs

@@ -34,6 +34,7 @@ namespace Tensorflow
         public ulong dataTypeSize => _handle == IntPtr.Zero ? 0 : c_api.TF_DataTypeSize(dtype);
         public ulong size => _handle == IntPtr.Zero ? 0 : bytesize / dataTypeSize;
         public IntPtr buffer => _handle == IntPtr.Zero ? IntPtr.Zero : c_api.TF_TensorData(_handle);
+        public int num_consumers(TF_Output oper_out) => _handle == IntPtr.Zero ? 0 : c_api.TF_OperationOutputNumConsumers(oper_out);
         public long[] shape
         {
             get
@@ -160,6 +161,13 @@ namespace Tensorflow
             this._dtype = dtype;
         }
 
+        public List<Operation> consumers()
+        {
+            var output = _as_tf_output();
+            var consumer_names = c_api.TF_OperationOutputConsumers_wrapper(output);
+            return consumer_names.Select(x => Graph.OperationByName(x)).ToList();
+        }
+
         public TF_Output _as_tf_output()
         {
             return new TF_Output(op, value_index);
@@ -225,7 +233,7 @@ namespace Tensorflow
                 }
             }
 
-            return $"{name} {dtype.ToString()} {rank} {string.Join(",", shape)}";
+            return $"{name} shape=({string.Join(",", shape)}) dtype={dtype.ToString()}";
         }
 
         public void Dispose()

src/TensorFlowNET.Core/Tensors/c_api.tensor.cs

@@ -5,7 +5,7 @@ using System.Text;
 
 namespace Tensorflow
 {
-    public static partial class c_api
+    public partial class c_api
     {
         /// <summary>
         /// Allocate and return a new Tensor.

src/TensorFlowNET.Core/Variables/RefVariable.cs

@@ -11,6 +11,7 @@ namespace Tensorflow
         public string _graph_key;
         public bool _trainable;
         public Tensor _variable;
+        public Tensor _snapshot;
 
         public RefVariable(object initial_value,
             bool trainable = true,
@@ -87,9 +88,12 @@ namespace Tensorflow
                 }
                 else
                 {
-
+                    _snapshot = gen_array_ops.identity(_variable, name = "read");
                 }
 
+                // clear g._name_stack
+                ops.get_default_graph().old_stack = "";
+
                 ops.add_to_collections(collections, this);
             }
         }