COMPMID-1595  Add UpsampleLayer to graph API

Change-Id: I7427b0fbb222ff9760d47b01a59aee654f2f860f
Reviewed-on: https://eu-gerrit-1.euhpc.arm.com/149587
Tested-by: bsgcomp <bsgcomp@arm.com>
Reviewed-by: Georgios Pinitas <georgios.pinitas@arm.com>
diff --git a/arm_compute/graph/backends/FunctionHelpers.h b/arm_compute/graph/backends/FunctionHelpers.h
index 7f5093a..32ef0aa 100644
--- a/arm_compute/graph/backends/FunctionHelpers.h
+++ b/arm_compute/graph/backends/FunctionHelpers.h
@@ -911,6 +911,47 @@
 
     return std::move(func);
 }
+/** Create a backend Upsample layer function
+ *
+ * @tparam UpsampleLayerFunction Backend Upsample function
+ * @tparam TargetInfo            Target-specific information
+ *
+ * @param[in] node Node to create the backend function for
+ * @param[in] ctx  Graph context
+ *
+ * @return Backend Upsample layer function
+ */
+template <typename UpsampleLayerFunction, typename TargetInfo>
+std::unique_ptr<IFunction> create_upsample_layer(UpsampleLayerNode &node, GraphContext &ctx)
+{
+    validate_node<TargetInfo>(node, 1 /* expected inputs */, 1 /* expected outputs */);
+
+    // Extract IO and info
+    typename TargetInfo::TensorType *input             = get_backing_tensor<TargetInfo>(node.input(0));
+    typename TargetInfo::TensorType *output            = get_backing_tensor<TargetInfo>(node.output(0));
+    const Size2D                     info              = node.info();
+    const InterpolationPolicy        upsampling_policy = node.upsampling_policy();
+    ARM_COMPUTE_ERROR_ON(upsampling_policy != InterpolationPolicy::NEAREST_NEIGHBOR);
+    ARM_COMPUTE_ERROR_ON(info.x() != 2 || info.y() != 2);
+    ARM_COMPUTE_ERROR_ON(input == nullptr);
+    ARM_COMPUTE_ERROR_ON(output == nullptr);
+
+    // Create and configure function
+    auto func = support::cpp14::make_unique<UpsampleLayerFunction>();
+    func->configure(input, output, info, upsampling_policy);
+
+    // Log info
+    ARM_COMPUTE_LOG_GRAPH_INFO("Instantiated " << node.type()
+                               << " Target " << TargetInfo::TargetType
+                               << " Data Type: " << input->info()->data_type()
+                               << " Input shape: " << input->info()->tensor_shape()
+                               << " Output shape: " << output->info()->tensor_shape()
+                               << " Strides: " << info
+                               << " Upsampling policy: " << upsampling_policy
+                               << std::endl);
+
+    return std::move(func);
+}
 /** Create a backend YOLO layer function
  *
  * @tparam YoloLayerFunction Backend YOLO function
diff --git a/arm_compute/graph/backends/ValidateHelpers.h b/arm_compute/graph/backends/ValidateHelpers.h
index 2dc3491..ff644c4 100644
--- a/arm_compute/graph/backends/ValidateHelpers.h
+++ b/arm_compute/graph/backends/ValidateHelpers.h
@@ -273,6 +273,28 @@
     return SliceLayer::validate(input, output, starts, ends);
 }
 
+/** Validates a Upsample layer node
+ *
+ * @tparam UpsampleLayer Upsample layer type
+ *
+ * @param[in] node Node to validate
+ *
+ * @return Status
+ */
+template <typename UpsampleLayer>
+Status validate_upsample_layer(UpsampleLayerNode &node)
+{
+    ARM_COMPUTE_LOG_GRAPH_VERBOSE("Validating UpsampleLayer node with ID : " << node.id() << " and Name: " << node.name() << std::endl);
+    ARM_COMPUTE_RETURN_ERROR_ON(node.num_inputs() != 1);
+    ARM_COMPUTE_RETURN_ERROR_ON(node.num_outputs() != 1);
+
+    // Extract input and output
+    arm_compute::ITensorInfo *input  = detail::get_backing_tensor_info(node.input(0));
+    arm_compute::ITensorInfo *output = get_backing_tensor_info(node.output(0));
+
+    // Validate function
+    return UpsampleLayer::validate(input, output, node.info(), node.upsampling_policy());
+}
 /** Validates a YOLO layer node
  *
  * @tparam YOLOLayer YOLO layer type