IVGCVSW-7342 Add Slice support to TOSA Reference Backend

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

7 files changed, 170 insertions, 1 deletions

diff --git a/src/backends/tosaCommon/TosaMappings.cpp b/src/backends/tosaCommon/TosaMappings.cpp
index 318735db77..15629ffab0 100644
--- a/src/backends/tosaCommon/TosaMappings.cpp
+++ b/src/backends/tosaCommon/TosaMappings.cpp
@@ -62,6 +62,11 @@ TosaSerializationBasicBlock* GetTosaMapping(const Layer* layer,
             auto reshapeDesc = PolymorphicDowncast<const ReshapeDescriptor*>(&descriptor);
             return ConvertReshapeToTosaOperator(layer, inputs, outputs, reshapeDesc);
         }
+        case LayerType::Slice:
+        {
+            auto sliceDesc = PolymorphicDowncast<const SliceDescriptor*>(&descriptor);
+            return ConvertSliceToTosaOperator(layer, inputs, outputs, sliceDesc);
+        }
         default:
         {
             return CreateEmptyTosaSerializationBasicBlock();
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
diff --git a/src/backends/tosaCommon/test/OneToOneMappingTests.cpp b/src/backends/tosaCommon/test/OneToOneMappingTests.cpp
index b1fa6847bc..07ffae41d1 100644
--- a/src/backends/tosaCommon/test/OneToOneMappingTests.cpp
+++ b/src/backends/tosaCommon/test/OneToOneMappingTests.cpp
@@ -375,6 +375,69 @@ TEST_CASE("GetTosaMappingFromLayer_ReshapeLayer")
                                         LayerType::Reshape);
 }
 
+TEST_CASE("GetTosaMapping_SliceLayer")
+{
+    TensorInfo inputInfo = TensorInfo({ 3, 2, 3 }, DataType::Float32);
+    TensorInfo outputInfo = TensorInfo({ 2, 1, 3 }, DataType::Float32);
+
+    std::vector<std::vector<int32_t>> inputShape  = {{ 3, 2, 3 }};
+    std::vector<std::vector<int32_t>> outputShape = {{ 2, 1, 3 }};
+
+    SliceDescriptor descriptor;
+    descriptor.m_Begin = { 3 };
+    descriptor.m_Size  = { 3 };
+
+    TosaSerializationBasicBlock* basicBlock =
+        GetTosaMapping(nullptr, LayerType::Slice, {&inputInfo}, {&outputInfo}, descriptor);
+    AssertTosaOneToOneMappingBasicBlock(basicBlock,
+                                        inputShape,
+                                        outputShape,
+                                        Op_SLICE,
+                                        Attribute_SliceAttribute,
+                                        descriptor,
+                                        LayerType::Slice);
+}
+
+TEST_CASE("GetTosaMappingFromLayer_SliceLayer")
+{
+    IRuntime::CreationOptions options;
+    IRuntimePtr runtime(IRuntime::Create(options));
+
+    // Builds up the structure of the network.
+    INetworkPtr net(INetwork::Create());
+
+    TensorInfo inputInfo = TensorInfo({ 3, 2, 3 }, DataType::Float32);
+    TensorInfo outputInfo = TensorInfo({ 2, 1, 3 }, DataType::Float32);
+
+    std::vector<std::vector<int32_t>> inputShape  = {{ 3, 2, 3 }};
+    std::vector<std::vector<int32_t>> outputShape = {{ 2, 1, 3 }};
+
+    SliceDescriptor descriptor;
+    descriptor.m_Begin = { 1, 0, 0 };
+    descriptor.m_Size  = { 2, 1, 3 };
+
+    IConnectableLayer* input  = net->AddInputLayer(0, "input");
+    IConnectableLayer* slice  = net->AddSliceLayer(descriptor, "slice");
+    IConnectableLayer* output = net->AddOutputLayer(0, "output");
+
+    input->GetOutputSlot(0).Connect(slice->GetInputSlot(0));
+    slice->GetOutputSlot(0).Connect(output->GetInputSlot(0));
+
+    input->GetOutputSlot(0).SetTensorInfo(inputInfo);
+    slice->GetOutputSlot(0).SetTensorInfo(outputInfo);
+
+    TosaSerializationBasicBlock* basicBlock =
+        GetTosaMappingFromLayer(PolymorphicDowncast<Layer*>(slice));
+    AssertTosaOneToOneMappingBasicBlock(basicBlock,
+                                        inputShape,
+                                        outputShape,
+                                        Op_SLICE,
+                                        Attribute_SliceAttribute,
+                                        descriptor,
+                                        LayerType::Slice);
+}
+
+
 TEST_CASE("GetTosaMapping_Unimplemented")
 {
     TosaSerializationBasicBlock* basicBlock =
diff --git a/src/backends/tosaCommon/test/TosaTestUtils.hpp b/src/backends/tosaCommon/test/TosaTestUtils.hpp
index 5c10a6d638..93b9e7d36f 100644
--- a/src/backends/tosaCommon/test/TosaTestUtils.hpp
+++ b/src/backends/tosaCommon/test/TosaTestUtils.hpp
@@ -122,6 +122,27 @@ inline void VerifyTosaAttribute(const BaseDescriptor& descriptor,
                                                              1,
                                                              std::multiplies<int32_t>());
             CHECK(numInputElements == numAttributeShapeElements);
+
+            break;
+        }
+        case LayerType::Slice:
+        {
+            auto sliceDesc = PolymorphicDowncast<const SliceDescriptor*>(&descriptor);
+            TosaSliceAttribute reshapeAttribute(attribute);
+
+            std::vector<int32_t> begin(sliceDesc->m_Begin.begin(), sliceDesc->m_Begin.end());
+            std::vector<int32_t> size(sliceDesc->m_Size.begin(), sliceDesc->m_Size.end());
+
+            CHECK(begin == reshapeAttribute.start());
+            CHECK(size == reshapeAttribute.size());
+
+            CHECK(begin.size() == inputShape.size());
+            CHECK(size.size() == inputShape.size());
+
+            CHECK(begin.size() == outputShape.size());
+            CHECK(size.size() == outputShape.size());
+
+            break;
         }
         default:
             break;