IVGCVSW-7833 Add ReverseV2 support to TFLite Parser

 * Added ReverseV2 support to TFLite Parser
 * Added ReverseV2 TFLite Parser unit tests
 * Updated Parser Docs

Signed-off-by: Tianle Cheng <tianle.cheng@arm.com>
Change-Id: Idb9a9213f75cd6cf01509a5d06ea5772cf56ac5b

5 files changed, 165 insertions, 0 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 148e77254d..537455d3b3 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -708,6 +708,7 @@ if(BUILD_UNIT_TESTS)
              src/armnnTfLiteParser/test/ReshapeDynamic.cpp
              src/armnnTfLiteParser/test/ResizeBilinear.cpp
              src/armnnTfLiteParser/test/ResizeNearestNeighbor.cpp
+             src/armnnTfLiteParser/test/ReverseV2.cpp
              src/armnnTfLiteParser/test/Quantize.cpp
              src/armnnTfLiteParser/test/Softmax.cpp
              src/armnnTfLiteParser/test/SpaceToBatchND.cpp
diff --git a/docs/05_01_parsers.dox b/docs/05_01_parsers.dox
index 08d569d065..cfce7ec580 100644
--- a/docs/05_01_parsers.dox
+++ b/docs/05_01_parsers.dox
@@ -173,6 +173,7 @@ The Arm NN SDK TensorFlow Lite parser currently supports the following operators
 - RESHAPE
 - RESIZE_BILINEAR
 - RESIZE_NEAREST_NEIGHBOR
+- REVERSE_V2
 - RSQRT
 - SHAPE
 - SIN
diff --git a/src/armnnTfLiteParser/TfLiteParser.cpp b/src/armnnTfLiteParser/TfLiteParser.cpp
index 1c5b4fc9f0..f44a747815 100644
--- a/src/armnnTfLiteParser/TfLiteParser.cpp
+++ b/src/armnnTfLiteParser/TfLiteParser.cpp
@@ -808,6 +808,7 @@ TfLiteParserImpl::TfLiteParserImpl(const Optional<ITfLiteParser::TfLiteParserOpt
     m_ParserFunctions[tflite::BuiltinOperator_RESHAPE]                 = &TfLiteParserImpl::ParseReshape;
     m_ParserFunctions[tflite::BuiltinOperator_RESIZE_BILINEAR]         = &TfLiteParserImpl::ParseResizeBilinear;
     m_ParserFunctions[tflite::BuiltinOperator_RESIZE_NEAREST_NEIGHBOR] = &TfLiteParserImpl::ParseResizeNearestNeighbor;
+    m_ParserFunctions[tflite::BuiltinOperator_REVERSE_V2]              = &TfLiteParserImpl::ParseReverseV2;
     m_ParserFunctions[tflite::BuiltinOperator_RSQRT]                   = &TfLiteParserImpl::ParseRsqrt;
     m_ParserFunctions[tflite::BuiltinOperator_SQRT]                    = &TfLiteParserImpl::ParseSqrt;
     m_ParserFunctions[tflite::BuiltinOperator_SHAPE]                   = &TfLiteParserImpl::ParseShape;
@@ -3276,6 +3277,67 @@ void TfLiteParserImpl::ParseResize(size_t subgraphIndex, size_t operatorIndex, R
     RegisterOutputSlots(subgraphIndex, operatorIndex, layer, outputTensorIndexes);
 }
 
+void TfLiteParserImpl::ParseReverseV2(size_t subgraphIndex, size_t operatorIndex)
+{
+    CHECK_MODEL(m_Model, subgraphIndex, operatorIndex);
+
+    auto inputs = GetInputs(m_Model, subgraphIndex, operatorIndex);
+    CHECK_VALID_SIZE(inputs.size(), 2);
+
+    auto outputs = GetOutputs(m_Model, subgraphIndex, operatorIndex);
+    CHECK_VALID_SIZE(outputs.size(), 1);
+
+    auto layerName = fmt::format("ReverseV2:{}:{}", subgraphIndex, operatorIndex);
+
+    TensorInfo inputTensorInfo = ToTensorInfo(inputs[0]);
+    TensorInfo axisTensorInfo = ToTensorInfo(inputs[1]);
+    TensorInfo outputTensorInfo = ToTensorInfo(outputs[0]);
+
+    std::vector<int32_t> axisTensorData(axisTensorInfo.GetNumElements());
+
+    BufferRawPtr axisBufferPtr = GetBuffer(m_Model, inputs[1]->buffer);
+    ::memcpy(axisTensorData.data(), axisBufferPtr->data.data(), axisTensorInfo.GetNumBytes());
+
+    ReverseV2Descriptor descriptor(axisTensorData);
+
+    auto inputRank = static_cast<int32_t>(inputTensorInfo.GetNumDimensions());
+    std::vector<bool> dimFlag(inputRank, false);
+
+    for (auto axis : axisTensorData)
+    {
+        if (axis < -inputRank || axis >= inputRank)
+        {
+            throw ParseException(
+                fmt::format("Operation has invalid axis: {} It is out of bounds [ -{}, {} ) {}",
+                            axis,
+                            inputRank, inputRank,
+                            CHECK_LOCATION().AsString()));
+        }
+
+        auto posAxis = axis < 0 ? axis + inputRank : axis;
+
+        if (dimFlag[posAxis])
+        {
+            throw ParseException(
+                fmt::format("Operation has repeated axis: {} {}",
+                            axis,
+                            CHECK_LOCATION().AsString()));
+        }
+        dimFlag[posAxis] = true;
+    }
+
+    IConnectableLayer* layer = m_Network->AddReverseV2Layer(descriptor, layerName.c_str());
+    ARMNN_ASSERT(layer != nullptr);
+
+    layer->GetOutputSlot(0).SetTensorInfo(outputTensorInfo);
+
+    auto inputTensorIndexes = AsUnsignedVector(GetInputTensorIds(m_Model, subgraphIndex, operatorIndex));
+    RegisterInputSlots(subgraphIndex, operatorIndex, layer, {inputTensorIndexes[0]});
+
+    auto outputTensorIndexes = AsUnsignedVector(GetOutputTensorIds(m_Model, subgraphIndex, operatorIndex));
+    RegisterOutputSlots(subgraphIndex, operatorIndex, layer, {outputTensorIndexes[0]});
+}
+
 void TfLiteParserImpl::ParseConcatenation(size_t subgraphIndex, size_t operatorIndex)
 {
     CHECK_MODEL(m_Model, subgraphIndex, operatorIndex);
diff --git a/src/armnnTfLiteParser/TfLiteParser.hpp b/src/armnnTfLiteParser/TfLiteParser.hpp
index 774d054572..dad2d67f3c 100644
--- a/src/armnnTfLiteParser/TfLiteParser.hpp
+++ b/src/armnnTfLiteParser/TfLiteParser.hpp
@@ -176,6 +176,7 @@ private:
     void ParseResize(size_t subgraphIndex, size_t operatorIndex, armnn::ResizeMethod resizeMethod);
     void ParseResizeBilinear(size_t subgraphIndex, size_t operatorIndex);
     void ParseResizeNearestNeighbor(size_t subgraphIndex, size_t operatorIndex);
+    void ParseReverseV2(size_t subgraphIndex, size_t operatorIndex);
     void ParseRsqrt(size_t subgraphIndex, size_t operatorIndex);
     void ParseShape(size_t subgraphIndex, size_t operatorIndex);
     void ParseSin(size_t subgraphIndex, size_t operatorIndex);
diff --git a/src/armnnTfLiteParser/test/ReverseV2.cpp b/src/armnnTfLiteParser/test/ReverseV2.cpp
new file mode 100644
index 0000000000..9604a3a1de
--- /dev/null
+++ b/src/armnnTfLiteParser/test/ReverseV2.cpp
@@ -0,0 +1,100 @@
+//
+// Copyright © 2023 Arm Ltd and Contributors. All rights reserved.
+// SPDX-License-Identifier: MIT
+//
+
+#include "ParserFlatbuffersFixture.hpp"
+
+TEST_SUITE("TensorflowLiteParser_ReverseV2")
+{
+struct ReverseV2Fixture : public ParserFlatbuffersFixture
+{
+    explicit ReverseV2Fixture(const std::string& inputShape,
+                              const std::string& outputShape,
+                              const std::string& axisShape,
+                              const std::string& axisData,
+                              const std::string& dataType = "FLOAT32",
+                              const std::string& scale = "1.0",
+                              const std::string& offset = "0")
+    {
+        m_JsonString = R"(
+            {
+                "version": 3,
+                "operator_codes": [ { "builtin_code": "REVERSE_V2" } ],
+                "subgraphs": [ {
+                    "tensors": [
+                        {
+                            "shape": )" + inputShape + R"(,
+                            "type": )" + dataType + R"(,
+                            "buffer": 0,
+                            "name": "inputTensor",
+                            "quantization": {
+                                "min": [ 0.0 ],
+                                "max": [ 255.0 ],
+                                "scale": [ )" + scale + R"( ],
+                                "zero_point": [ )" + offset + R"( ],
+                            }
+                        },
+                        {
+                             "shape": )" + axisShape + R"( ,
+                             "type": "INT32",
+                             "buffer": 1,
+                             "name": "axis",
+                             "quantization": {
+                                "min": [ 0.0 ],
+                                "max": [ 255.0 ],
+                                "scale": [ 1.0 ],
+                                "zero_point": [ 0 ],
+                             }
+                        },
+                        {
+                             "shape": )" + outputShape + R"(,
+                             "type": )" + dataType + R"(,
+                             "buffer": 2,
+                             "name": "outputTensor",
+                             "quantization": {
+                                "min": [ 0.0 ],
+                                "max": [ 255.0 ],
+                                "scale": [ )" + scale + R"( ],
+                                "zero_point": [ )" + offset + R"( ],
+                            }
+                        }
+                    ],
+                    "inputs": [ 0, 1 ],
+                    "outputs": [ 2 ],
+                    "operators": [
+                        {
+                            "opcode_index": 0,
+                            "inputs": [ 0, 1 ],
+                            "outputs": [ 2 ],
+                            "builtin_options_type": "ReverseV2Options",
+                            "builtin_options": {},
+                            "custom_options_format": "FLEXBUFFERS"
+                        }
+                    ],
+                } ],
+                "buffers" : [
+                    { },
+                    { "data": )" + axisData + R"(, },
+                    { },
+                ]
+            }
+        )";
+        Setup();
+    }
+};
+
+struct SimpleReverseV2Fixture : public ReverseV2Fixture
+{
+    SimpleReverseV2Fixture() : ReverseV2Fixture("[ 2, 2, 2 ]", "[ 2, 2, 2 ]", "[ 2 ]", "[ 0,0,0,0, 1,0,0,0 ]") {}
+};
+
+TEST_CASE_FIXTURE(SimpleReverseV2Fixture, "ParseReverseV2")
+{
+    RunTest<3, armnn::DataType::Float32>
+        (0,
+        {{ "inputTensor",  { 1, 2, 3, 4, 5, 6, 7, 8 }}},
+        {{ "outputTensor", { 7, 8, 5, 6, 3, 4, 1, 2 }}});
+}
+
+}
\ No newline at end of file