IVGCVSW-7342 Add Slice support to TOSA Reference Backend

Signed-off-by: Cathal Corbett <cathal.corbett@arm.com>
Change-Id: I8be286b69bebd4cd36033e3145632bb043938d16

4 files changed, 81 insertions, 1 deletions

diff --git a/src/backends/tosaCommon/operatorMappings/CMakeLists.txt b/src/backends/tosaCommon/operatorMappings/CMakeLists.txt
index 7733d01abb..cb1d68e625 100644
--- a/src/backends/tosaCommon/operatorMappings/CMakeLists.txt
+++ b/src/backends/tosaCommon/operatorMappings/CMakeLists.txt
@@ -16,6 +16,8 @@ list(APPEND armnnTosaBackendOperators_sources
         Pooling2DOperator.cpp
         ReshapeOperator.hpp
         ReshapeOperator.cpp
+        SliceOperator.hpp
+        SliceOperator.cpp
         TosaOperatorUtils.hpp
     )
 
diff --git a/src/backends/tosaCommon/operatorMappings/SliceOperator.cpp b/src/backends/tosaCommon/operatorMappings/SliceOperator.cpp
new file mode 100644
index 0000000000..fc2e40a95c
--- /dev/null
+++ b/src/backends/tosaCommon/operatorMappings/SliceOperator.cpp
@@ -0,0 +1,57 @@
+//
+// Copyright © 2022 Arm Ltd and Contributors. All rights reserved.
+// SPDX-License-Identifier: MIT
+//
+
+#include "SliceOperator.hpp"
+
+TosaSerializationBasicBlock* ConvertSliceToTosaOperator(const Layer* layer,
+                                                        const std::vector<const TensorInfo*>& inputs,
+                                                        const std::vector<const TensorInfo*>& outputs,
+                                                        const SliceDescriptor* sliceDescriptor)
+{
+    std::string inputName = std::string("input0_");
+    std::string outputName = std::string("output0_");
+    std::string blockName  = std::string("Op_SLICE_block_") + GetUniqueTosaMappingID();
+
+    // If a layer is present then the block will be used for execution, so input and output names need to be determined
+    // using the previous and following layers so the graph is connected correctly. For validation this doesn't matter.
+    if(layer != nullptr)
+    {
+        // Get the layers connected to the input slots and determine unique layer names.
+        Layer& connectedLayer = layer->GetInputSlot(0).GetConnectedOutputSlot()->GetOwningLayer();
+        inputName = GenerateUniqueName(connectedLayer, 0);
+
+        // Get the layer connected to the output slot and determine unique layer name.
+        Layer& connectedOutputLayer = layer->GetOutputSlot().GetConnection(0)->GetOwningLayer();
+        outputName = GenerateUniqueName(connectedOutputLayer, 0);
+    }
+
+    std::vector<int32_t> begin(sliceDescriptor->m_Begin.begin(), sliceDescriptor->m_Begin.end());
+    std::vector<int32_t> size(sliceDescriptor->m_Size.begin(), sliceDescriptor->m_Size.end());
+
+    TosaSliceAttribute attribute(begin, size);
+
+    auto* op = new TosaSerializationOperator(Op_SLICE,
+                                             Attribute_SliceAttribute,
+                                             &attribute,
+                                             {inputName},
+                                             {outputName});
+
+    std::vector<int32_t> inputShape = GetTosaTensorShape(inputs[0]->GetShape());
+    DType inputDType = ArmNNToDType(inputs[0]->GetDataType());
+
+    std::vector<int32_t> outputShape = GetTosaTensorShape(outputs[0]->GetShape());
+    DType outputDType = ArmNNToDType(outputs[0]->GetDataType());
+
+    auto* inputTensor  = new TosaSerializationTensor(inputName, inputShape, inputDType, {});
+    auto* outputTensor = new TosaSerializationTensor(outputName, outputShape, outputDType, {});
+
+    // operatorInputNames/operatorOutputNames ends up being the same as
+    // blockInputNames/blockOutputNames for one-to-one ArmNN to TOSA mappings
+    return new TosaSerializationBasicBlock(blockName, // name
+                                           {op}, // operators
+                                           {inputTensor, outputTensor}, // tensors
+                                           {inputName}, // inputs
+                                           {outputName}); // outputs
+}
\ No newline at end of file
diff --git a/src/backends/tosaCommon/operatorMappings/SliceOperator.hpp b/src/backends/tosaCommon/operatorMappings/SliceOperator.hpp
new file mode 100644
index 0000000000..127cc81255
--- /dev/null
+++ b/src/backends/tosaCommon/operatorMappings/SliceOperator.hpp
@@ -0,0 +1,20 @@
+//
+// Copyright © 2022 Arm Ltd and Contributors. All rights reserved.
+// SPDX-License-Identifier: MIT
+//
+
+#pragma once
+
+#include "TosaOperatorUtils.hpp"
+
+#include <Layer.hpp>
+
+#include <tosa_serialization_handler.h>
+
+using namespace armnn;
+using namespace tosa;
+
+TosaSerializationBasicBlock* ConvertSliceToTosaOperator(const Layer* layer,
+                                                        const std::vector<const TensorInfo*>& inputs,
+                                                        const std::vector<const TensorInfo*>& outputs,
+                                                        const SliceDescriptor* sliceDescriptor);
\ No newline at end of file
diff --git a/src/backends/tosaCommon/operatorMappings/TosaCommonOperators.hpp b/src/backends/tosaCommon/operatorMappings/TosaCommonOperators.hpp
index 0711095a25..a3597f0461 100644
--- a/src/backends/tosaCommon/operatorMappings/TosaCommonOperators.hpp
+++ b/src/backends/tosaCommon/operatorMappings/TosaCommonOperators.hpp
@@ -10,4 +10,5 @@
 #include "Conv2dOperator.hpp"
 #include "AvgPool2DIgnoreValueOperator.hpp"
 #include "Pooling2DOperator.hpp"
-#include "ReshapeOperator.hpp"
\ No newline at end of file
+#include "ReshapeOperator.hpp"
+#include "SliceOperator.hpp"
\ No newline at end of file