From 0d6b287955630df34c81fe94ab92dcfa81192373 Mon Sep 17 00:00:00 2001
From: Oceania2018 <haiping008@gmail.com>
Date: Thu, 8 Aug 2019 07:32:21 -0500
Subject: [PATCH] Allocate tensor without memory copy

---
 .../Tensors/Tensor.Creation.cs                | 144 ++++++++++++++++--
 1 file changed, 135 insertions(+), 9 deletions(-)

diff --git a/src/TensorFlowNET.Core/Tensors/Tensor.Creation.cs b/src/TensorFlowNET.Core/Tensors/Tensor.Creation.cs
index a104f066..896d6d4d 100644
--- a/src/TensorFlowNET.Core/Tensors/Tensor.Creation.cs
+++ b/src/TensorFlowNET.Core/Tensors/Tensor.Creation.cs
@@ -506,7 +506,7 @@ namespace Tensorflow
             IsMemoryOwner = true;
         }
 
-        private unsafe IntPtr Allocate(NDArray nd, TF_DataType? tensorDType = null)
+        private unsafe IntPtr AllocateWithMemoryCopy(NDArray nd, TF_DataType? tensorDType = null)
         {
             IntPtr dotHandle = IntPtr.Zero;
             int buffersize = 0;
@@ -520,30 +520,30 @@ namespace Tensorflow
             var dataType = ToTFDataType(nd.dtype);
             // shape
             var dims = nd.shape.Select(x => (long)x).ToArray();
-            var nd1 = nd.ravel();
+            // var nd1 = nd.ravel();
             switch (nd.dtype.Name)
             {
                 case "Boolean":
-                    var boolVals = Array.ConvertAll(nd1.Data<bool>(), x => Convert.ToByte(x));
+                    var boolVals = Array.ConvertAll(nd.Data<bool>(), x => Convert.ToByte(x));
                     Marshal.Copy(boolVals, 0, dotHandle, nd.size);
                     break;
                 case "Int16":
-                    Marshal.Copy(nd1.Data<short>(), 0, dotHandle, nd.size);
+                    Marshal.Copy(nd.Data<short>(), 0, dotHandle, nd.size);
                     break;
                 case "Int32":
-                    Marshal.Copy(nd1.Data<int>(), 0, dotHandle, nd.size);
+                    Marshal.Copy(nd.Data<int>(), 0, dotHandle, nd.size);
                     break;
                 case "Int64":
-                    Marshal.Copy(nd1.Data<long>(), 0, dotHandle, nd.size);
+                    Marshal.Copy(nd.Data<long>(), 0, dotHandle, nd.size);
                     break;
                 case "Single":
-                    Marshal.Copy(nd1.Data<float>(), 0, dotHandle, nd.size);
+                    Marshal.Copy(nd.Data<float>(), 0, dotHandle, nd.size);
                     break;
                 case "Double":
-                    Marshal.Copy(nd1.Data<double>(), 0, dotHandle, nd.size);
+                    Marshal.Copy(nd.Data<double>(), 0, dotHandle, nd.size);
                     break;
                 case "Byte":
-                    Marshal.Copy(nd1.Data<byte>(), 0, dotHandle, nd.size);
+                    Marshal.Copy(nd.Data<byte>(), 0, dotHandle, nd.size);
                     break;
                 case "String":
                     return new Tensor(UTF8Encoding.UTF8.GetBytes(nd.Data<string>(0)), TF_DataType.TF_STRING);
@@ -559,6 +559,132 @@ namespace Tensorflow
                 ref _deallocatorArgs);
 
             return tfHandle;
+        }
+
+        private unsafe IntPtr Allocate(NDArray nd, TF_DataType? tensorDType = null)
+        {
+            IntPtr dotHandle = IntPtr.Zero;
+            IntPtr tfHandle = IntPtr.Zero;
+            int buffersize = nd.size * nd.dtypesize;
+
+            var dataType = ToTFDataType(nd.dtype);
+            // shape
+            var dims = nd.shape.Select(x => (long)x).ToArray();
+            switch (nd.dtype.Name)
+            {
+                case "Boolean":
+                    {
+                        var boolVals = Array.ConvertAll(nd.Data<bool>(), x => Convert.ToByte(x));
+                        var array = nd.Data<byte>();
+                        fixed (byte* h = &array[0])
+                        {
+                            tfHandle = c_api.TF_NewTensor(dataType,
+                                dims,
+                                dims.Length,
+                                new IntPtr(h),
+                                (UIntPtr)buffersize,
+                                _nothingDeallocator,
+                                ref _deallocatorArgs);
+                        }
+                    }
+                    break;
+                case "Int16":
+                    {
+                        var array = nd.Data<short>();
+                        fixed (short* h = &array[0])
+                        {
+                            tfHandle = c_api.TF_NewTensor(dataType,
+                                dims,
+                                dims.Length,
+                                new IntPtr(h),
+                                (UIntPtr)buffersize,
+                                _nothingDeallocator,
+                                ref _deallocatorArgs);
+                        }
+                    }
+                    break;
+                case "Int32":
+                    {
+                        var array = nd.Data<int>();
+                        fixed (int* h = &array[0])
+                        {
+                            tfHandle = c_api.TF_NewTensor(dataType,
+                                dims,
+                                dims.Length,
+                                new IntPtr(h),
+                                (UIntPtr)buffersize,
+                                _nothingDeallocator,
+                                ref _deallocatorArgs);
+                        }
+                    }
+                    break;
+                case "Int64":
+                    {
+                        var array = nd.Data<long>();
+                        fixed (long* h = &array[0])
+                        {
+                            tfHandle = c_api.TF_NewTensor(dataType,
+                                dims,
+                                dims.Length,
+                                new IntPtr(h),
+                                (UIntPtr)buffersize,
+                                _nothingDeallocator,
+                                ref _deallocatorArgs);
+                        }
+                    }
+                    break;
+                case "Single":
+                    {
+                        var array = nd.Data<float>();
+                        fixed (float* h = &array[0])
+                        {
+                            tfHandle = c_api.TF_NewTensor(dataType,
+                                dims,
+                                dims.Length,
+                                new IntPtr(h),
+                                (UIntPtr)buffersize,
+                                _nothingDeallocator,
+                                ref _deallocatorArgs);
+                        }
+                    }
+                    break;
+                case "Double":
+                    {
+                        var array = nd.Data<double>();
+                        fixed (double* h = &array[0])
+                        {
+                            tfHandle = c_api.TF_NewTensor(dataType,
+                                dims,
+                                dims.Length,
+                                new IntPtr(h),
+                                (UIntPtr)buffersize,
+                                _nothingDeallocator,
+                                ref _deallocatorArgs);
+                        }
+                    }
+                    break;
+                case "Byte":
+                    {
+                        var array = nd.Data<byte>();
+                        fixed (byte* h = &array[0])
+                        {
+                            tfHandle = c_api.TF_NewTensor(dataType,
+                                dims,
+                                dims.Length,
+                                new IntPtr(h),
+                                (UIntPtr)buffersize,
+                                _nothingDeallocator,
+                                ref _deallocatorArgs);
+                        }
+                    }
+                    break;
+                case "String":
+                    return new Tensor(UTF8Encoding.UTF8.GetBytes(nd.Data<string>(0)), TF_DataType.TF_STRING);
+                default:
+                    throw new NotImplementedException($"Marshal.Copy failed for {nd.dtype.Name}.");
+            }
+
+            return tfHandle;
         }
 
         public unsafe Tensor(byte[][] buffer, long[] shape)