IVGCVSW-2030 and IVGCVSW-2031 Add MaxPooling support and unit test to TfLite Parser

Change-Id: I3aea8ea6d018900682d278f28a50e40cf2f963fe
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8182c22..e312b36 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -413,6 +413,7 @@
              src/armnnTfLiteParser/test/Concatenation.cpp
              src/armnnTfLiteParser/test/Conv2D.cpp
              src/armnnTfLiteParser/test/DepthwiseConvolution2D.cpp
+             src/armnnTfLiteParser/test/MaxPool2D.cpp
              src/armnnTfLiteParser/test/Reshape.cpp
              src/armnnTfLiteParser/test/Softmax.cpp
              src/armnnTfLiteParser/test/Squeeze.cpp
diff --git a/src/armnnTfLiteParser/TfLiteParser.cpp b/src/armnnTfLiteParser/TfLiteParser.cpp
index 66746e4..216c090 100644
--- a/src/armnnTfLiteParser/TfLiteParser.cpp
+++ b/src/armnnTfLiteParser/TfLiteParser.cpp
@@ -456,6 +456,7 @@
     m_ParserFunctions[tflite::BuiltinOperator_CONCATENATION]     =  &TfLiteParser::ParseConcatenation;
     m_ParserFunctions[tflite::BuiltinOperator_CONV_2D]           =  &TfLiteParser::ParseConv2D;
     m_ParserFunctions[tflite::BuiltinOperator_DEPTHWISE_CONV_2D] =  &TfLiteParser::ParseDepthwiseConv2D;
+    m_ParserFunctions[tflite::BuiltinOperator_MAX_POOL_2D]       =  &TfLiteParser::ParseMaxPool2D;
     m_ParserFunctions[tflite::BuiltinOperator_RELU]              =  &TfLiteParser::ParseRelu;
     m_ParserFunctions[tflite::BuiltinOperator_RELU6]             =  &TfLiteParser::ParseRelu6;
     m_ParserFunctions[tflite::BuiltinOperator_RESHAPE]           =  &TfLiteParser::ParseReshape;
@@ -647,63 +648,6 @@
                           CHECK_LOCATION().AsString()));
 }
 
-void TfLiteParser::ParseAveragePool2D(size_t subgraphIndex, size_t operatorIndex)
-{
-    CHECK_MODEL(m_Model, subgraphIndex, operatorIndex);
-
-    const auto & operatorPtr = m_Model->subgraphs[subgraphIndex]->operators[operatorIndex];
-    const auto * options = operatorPtr->builtin_options.AsPool2DOptions();
-
-    CHECK_SUPPORTED_FUSED_ACTIVATION(options, subgraphIndex, operatorIndex);
-
-    Pooling2dDescriptor desc;
-
-    desc.m_PoolType = PoolingAlgorithm::Average;
-    desc.m_StrideX = CHECKED_NON_NEGATIVE(options->stride_w);
-    desc.m_StrideY = CHECKED_NON_NEGATIVE(options->stride_h);
-    desc.m_PoolWidth = CHECKED_NON_NEGATIVE(options->filter_width);
-    desc.m_PoolHeight = CHECKED_NON_NEGATIVE(options->filter_height);
-    desc.m_PaddingMethod = PaddingMethod::Exclude;
-    desc.m_OutputShapeRounding = OutputShapeRounding::Floor;
-
-    auto inputs = GetInputs(m_Model, subgraphIndex, operatorIndex);
-    CHECK_VALID_SIZE(inputs.size(), 1);
-    armnn::TensorInfo inputTensorInfo  = ToTensorInfo(inputs[0]);
-
-    // assuming input is NHWC
-    unsigned int inputHeight = inputTensorInfo.GetShape()[1];
-    unsigned int inputWidth  = inputTensorInfo.GetShape()[2];
-
-    CalcPadding(inputHeight, desc.m_PoolHeight, desc.m_StrideY, desc.m_PadTop, desc.m_PadBottom, options->padding);
-    CalcPadding(inputWidth, desc.m_PoolWidth, desc.m_StrideX, desc.m_PadLeft, desc.m_PadRight, options->padding);
-
-    auto outputs = GetOutputs(m_Model, subgraphIndex, operatorIndex);
-    CHECK_VALID_SIZE(outputs.size(), 1);
-    armnn::TensorInfo outputTensorInfo  = ToTensorInfo(outputs[0]);
-
-    auto layerName = boost::str(boost::format("AveragePool2D:%1%:%2%") % subgraphIndex % operatorIndex);
-    IConnectableLayer* layer = m_Network->AddPooling2dLayer(desc, layerName.c_str());
-
-    BOOST_ASSERT(layer != nullptr);
-
-    // add permute layers to swizzle the input and deswizzle the output
-    std::pair<IConnectableLayer*, IConnectableLayer*> permuteLayers =
-            SwizzleInDeswizzleOut(*m_Network, layer, 0, inputTensorInfo, 0, outputTensorInfo);
-
-    // register the input connection slots for the layer, connections are made after all layers have been created
-    // only the tensors for the inputs are relevant, exclude the const tensors
-    auto inputTensorIndexes = AsUnsignedVector(GetInputTensorIds(m_Model, subgraphIndex, operatorIndex));
-    RegisterInputSlots(subgraphIndex, operatorIndex, permuteLayers.first, {inputTensorIndexes[0]});
-
-    // we need to add the activation layer and fortunately we don't need to care about the data layout
-    // beause the activation function is element-wise, so it is OK to have the activation after the trailing
-    // swizzle layer
-    layer = AddFusedActivationLayer(permuteLayers.second, 0, options->fused_activation_function);
-    // register the output connection slots for the layer, connections are made after all layers have been created
-    auto outputTensorIndexes = AsUnsignedVector(GetOutputTensorIds(m_Model, subgraphIndex, operatorIndex));
-    RegisterOutputSlots(subgraphIndex, operatorIndex, layer, {outputTensorIndexes[0]});
-}
-
 void TfLiteParser::ParseConv2D(size_t subgraphIndex, size_t operatorIndex)
 {
     CHECK_MODEL(m_Model, subgraphIndex, operatorIndex);
@@ -857,6 +801,90 @@
     RegisterOutputSlots(subgraphIndex, operatorIndex, layer, {outputTensorIndexes[0]});
 }
 
+void TfLiteParser::ParseAveragePool2D(size_t subgraphIndex, size_t operatorIndex)
+{
+    ParsePool(subgraphIndex, operatorIndex, PoolingAlgorithm::Average);
+}
+
+void TfLiteParser::ParseMaxPool2D(size_t subgraphIndex, size_t operatorIndex)
+{
+    ParsePool(subgraphIndex, operatorIndex, PoolingAlgorithm::Max);
+}
+
+void TfLiteParser::ParsePool(size_t subgraphIndex,
+                             size_t operatorIndex,
+                             PoolingAlgorithm algorithm)
+{
+    CHECK_MODEL(m_Model, subgraphIndex, operatorIndex);
+
+    const auto & operatorPtr = m_Model->subgraphs[subgraphIndex]->operators[operatorIndex];
+    const auto * options = operatorPtr->builtin_options.AsPool2DOptions();
+
+    CHECK_SUPPORTED_FUSED_ACTIVATION(options, subgraphIndex, operatorIndex);
+
+    std::string layerName;
+
+    switch (algorithm)
+    {
+        case PoolingAlgorithm::Average:
+            layerName =
+                boost::str(boost::format("AveragePool2D:%1%:%2%") % subgraphIndex % operatorIndex);
+            break;
+        case PoolingAlgorithm::Max:
+            layerName =
+                boost::str(boost::format("MaxPool2D:%1%:%2%") % subgraphIndex % operatorIndex);
+            break;
+        default:
+            BOOST_ASSERT_MSG(false, "Unsupported Pooling Algorithm");
+    }
+
+    Pooling2dDescriptor desc;
+
+    desc.m_PoolType = algorithm;
+    desc.m_StrideX = CHECKED_NON_NEGATIVE(options->stride_w);
+    desc.m_StrideY = CHECKED_NON_NEGATIVE(options->stride_h);
+    desc.m_PoolWidth = CHECKED_NON_NEGATIVE(options->filter_width);
+    desc.m_PoolHeight = CHECKED_NON_NEGATIVE(options->filter_height);
+    desc.m_PaddingMethod = PaddingMethod::Exclude;
+    desc.m_OutputShapeRounding = OutputShapeRounding::Floor;
+
+    auto inputs = GetInputs(m_Model, subgraphIndex, operatorIndex);
+    CHECK_VALID_SIZE(inputs.size(), 1);
+    armnn::TensorInfo inputTensorInfo  = ToTensorInfo(inputs[0]);
+
+    // assuming input is NHWC
+    unsigned int inputHeight = inputTensorInfo.GetShape()[1];
+    unsigned int inputWidth  = inputTensorInfo.GetShape()[2];
+
+    CalcPadding(inputHeight, desc.m_PoolHeight, desc.m_StrideY, desc.m_PadTop, desc.m_PadBottom, options->padding);
+    CalcPadding(inputWidth, desc.m_PoolWidth, desc.m_StrideX, desc.m_PadLeft, desc.m_PadRight, options->padding);
+
+    auto outputs = GetOutputs(m_Model, subgraphIndex, operatorIndex);
+    CHECK_VALID_SIZE(outputs.size(), 1);
+    armnn::TensorInfo outputTensorInfo  = ToTensorInfo(outputs[0]);
+
+    IConnectableLayer* layer = m_Network->AddPooling2dLayer(desc, layerName.c_str());
+
+    BOOST_ASSERT(layer != nullptr);
+
+    // add permute layers to swizzle the input and deswizzle the output
+    std::pair<IConnectableLayer*, IConnectableLayer*> permuteLayers =
+            SwizzleInDeswizzleOut(*m_Network, layer, 0, inputTensorInfo, 0, outputTensorInfo);
+
+    // register the input connection slots for the layer, connections are made after all layers have been created
+    // only the tensors for the inputs are relevant, exclude the const tensors
+    auto inputTensorIndexes = AsUnsignedVector(GetInputTensorIds(m_Model, subgraphIndex, operatorIndex));
+    RegisterInputSlots(subgraphIndex, operatorIndex, permuteLayers.first, {inputTensorIndexes[0]});
+
+    // we need to add the activation layer and fortunately we don't need to care about the data layout
+    // beause the activation function is element-wise, so it is OK to have the activation after the trailing
+    // swizzle layer
+    layer = AddFusedActivationLayer(permuteLayers.second, 0, options->fused_activation_function);
+    // register the output connection slots for the layer, connections are made after all layers have been created
+    auto outputTensorIndexes = AsUnsignedVector(GetOutputTensorIds(m_Model, subgraphIndex, operatorIndex));
+    RegisterOutputSlots(subgraphIndex, operatorIndex, layer, {outputTensorIndexes[0]});
+}
+
 void TfLiteParser::ParseSoftmax(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 620648a..35f0b64 100644
--- a/src/armnnTfLiteParser/TfLiteParser.hpp
+++ b/src/armnnTfLiteParser/TfLiteParser.hpp
@@ -6,6 +6,7 @@
 
 #include "armnn/INetwork.hpp"
 #include "armnnTfLiteParser/ITfLiteParser.hpp"
+#include "armnn/Types.hpp"
 
 #include <schema_generated.h>
 #include <functional>
@@ -93,12 +94,15 @@
     void ParseConcatenation(size_t subgraphIndex, size_t operatorIndex);
     void ParseConv2D(size_t subgraphIndex, size_t operatorIndex);
     void ParseDepthwiseConv2D(size_t subgraphIndex, size_t operatorIndex);
+    void ParseMaxPool2D(size_t subgraphIndex, size_t operatorIndex);
     void ParseRelu(size_t subgraphIndex, size_t operatorIndex);
     void ParseRelu6(size_t subgraphIndex, size_t operatorIndex);
     void ParseReshape(size_t subgraphIndex, size_t operatorIndex);
     void ParseSoftmax(size_t subgraphIndex, size_t operatorIndex);
     void ParseSqueeze(size_t subgraphIndex, size_t operatorIndex);
 
+    void ParsePool(size_t subgraphIndex, size_t operatorIndex, armnn::PoolingAlgorithm algorithm);
+
     void RegisterProducerOfTensor(size_t subgraphIndex, size_t tensorIndex, armnn::IOutputSlot* slot);
     void RegisterConsumerOfTensor(size_t subgraphIndex, size_t tensorIndex, armnn::IInputSlot* slot);
     void RegisterInputSlots(size_t subgraphIndex,
diff --git a/src/armnnTfLiteParser/test/MaxPool2D.cpp b/src/armnnTfLiteParser/test/MaxPool2D.cpp
new file mode 100644
index 0000000..06bf780
--- /dev/null
+++ b/src/armnnTfLiteParser/test/MaxPool2D.cpp
@@ -0,0 +1,119 @@
+//
+// Copyright © 2017 Arm Ltd. All rights reserved.
+// SPDX-License-Identifier: MIT
+//
+#include <boost/test/unit_test.hpp>
+#include "armnnTfLiteParser/ITfLiteParser.hpp"
+#include "ParserFlatbuffersFixture.hpp"
+
+BOOST_AUTO_TEST_SUITE(TensorflowLiteParser)
+
+struct MaxPool2DFixture : public ParserFlatbuffersFixture
+{
+    explicit MaxPool2DFixture(std::string inputdim, std::string outputdim, std::string dataType)
+    {
+        m_JsonString = R"(
+        {
+            "version": 3,
+            "operator_codes": [ { "builtin_code": "MAX_POOL_2D" } ],
+            "subgraphs": [
+            {
+                "tensors": [
+                {
+                    "shape": )"
+                    + outputdim
+                    + R"(,
+                    "type": )"
+                      + dataType
+                      + R"(,
+                            "buffer": 0,
+                            "name": "OutputTensor",
+                            "quantization": {
+                                "min": [ 0.0 ],
+                                "max": [ 255.0 ],
+                                "scale": [ 1.0 ],
+                                "zero_point": [ 0 ]
+                            }
+                },
+                {
+                    "shape": )"
+                    + inputdim
+                    + R"(,
+                    "type": )"
+                      + dataType
+                      + R"(,
+                            "buffer": 1,
+                            "name": "InputTensor",
+                            "quantization": {
+                                "min": [ 0.0 ],
+                                "max": [ 255.0 ],
+                                "scale": [ 1.0 ],
+                                "zero_point": [ 0 ]
+                            }
+                }
+                ],
+                "inputs": [ 1 ],
+                "outputs": [ 0 ],
+                "operators": [ {
+                        "opcode_index": 0,
+                        "inputs": [ 1 ],
+                        "outputs": [ 0 ],
+                        "builtin_options_type": "Pool2DOptions",
+                        "builtin_options":
+                        {
+                            "padding": "VALID",
+                            "stride_w": 2,
+                            "stride_h": 2,
+                            "filter_width": 2,
+                            "filter_height": 2,
+                            "fused_activation_function": "NONE"
+                        },
+                        "custom_options_format": "FLEXBUFFERS"
+                    } ]
+                }
+            ],
+            "description": "MaxPool2D test.",
+            "buffers" : [ {}, {} ]
+        })";
+
+        SetupSingleInputSingleOutput("InputTensor", "OutputTensor");
+    }
+};
+
+
+struct MaxPoolLiteFixtureUint1DOutput : MaxPool2DFixture
+{
+    MaxPoolLiteFixtureUint1DOutput() : MaxPool2DFixture("[ 1, 2, 2, 1 ]", "[ 1, 1, 1, 1 ]", "UINT8") {}
+};
+
+struct MaxPoolLiteFixtureFloat1DOutput : MaxPool2DFixture
+{
+    MaxPoolLiteFixtureFloat1DOutput() : MaxPool2DFixture("[ 1, 2, 2, 1 ]", "[ 1, 1, 1, 1 ]", "FLOAT32") {}
+};
+
+struct MaxPoolLiteFixtureUint2DOutput : MaxPool2DFixture
+{
+    MaxPoolLiteFixtureUint2DOutput() : MaxPool2DFixture("[ 1, 4, 4, 1 ]", "[ 1, 2, 2, 1 ]", "UINT8") {}
+};
+
+BOOST_FIXTURE_TEST_CASE(MaxPoolLiteUint1DOutput, MaxPoolLiteFixtureUint1DOutput)
+{
+    RunTest<4, uint8_t>(0, { 2, 3, 5, 2 }, { 5 });
+}
+
+BOOST_FIXTURE_TEST_CASE(MaxPoolLiteFloat1DOutput, MaxPoolLiteFixtureFloat1DOutput)
+{
+    RunTest<4, float>(0, { 2.0f, 3.0f, 5.0f, 2.0f },  { 5.0f });
+}
+
+BOOST_FIXTURE_TEST_CASE(MaxPoolLiteUint2DOutput, MaxPoolLiteFixtureUint2DOutput)
+{
+    RunTest<4, uint8_t>(0, { 1, 2, 2, 3, 5, 6, 7, 8, 3, 2, 1, 0, 1, 2, 3, 4 }, { 6, 8, 3, 4 });
+}
+
+BOOST_FIXTURE_TEST_CASE(MaxPoolIncorrectDataTypeError, MaxPoolLiteFixtureFloat1DOutput)
+{
+    BOOST_CHECK_THROW((RunTest<4, uint8_t>(0, { 2, 3, 5, 2 }, { 5 })), armnn::Exception);
+}
+
+BOOST_AUTO_TEST_SUITE_END()