COMPMID-992 Implement CL RNN function

Change-Id: I8dbada5fabedbb8523e433ba73d504bd15b81466
Reviewed-on: https://eu-gerrit-1.euhpc.arm.com/125787
Reviewed-by: Georgios Pinitas <georgios.pinitas@arm.com>
Tested-by: Jenkins <bsgcomp@arm.com>
diff --git a/arm_compute/runtime/CL/functions/CLRNNLayer.h b/arm_compute/runtime/CL/functions/CLRNNLayer.h
new file mode 100644
index 0000000..9f239a9
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+++ b/arm_compute/runtime/CL/functions/CLRNNLayer.h
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+/*
+ * Copyright (c) 2018 ARM Limited.
+ *
+ * SPDX-License-Identifier: MIT
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+#ifndef __ARM_COMPUTE_CLRNN_LAYER_H__
+#define __ARM_COMPUTE_CLRNN_LAYER_H__
+
+#include "arm_compute/core/CL/kernels/CLActivationLayerKernel.h"
+#include "arm_compute/core/CL/kernels/CLArithmeticAdditionKernel.h"
+#include "arm_compute/core/CL/kernels/CLCopyKernel.h"
+#include "arm_compute/runtime/CL/ICLSimpleFunction.h"
+#include "arm_compute/runtime/CL/functions/CLFullyConnectedLayer.h"
+#include "arm_compute/runtime/CL/functions/CLGEMM.h"
+
+namespace arm_compute
+{
+class ICLTensor;
+
+/** Basic function to run @ref CLRNNLayer */
+class CLRNNLayer : public IFunction
+{
+public:
+    /** Default constructor */
+    CLRNNLayer(std::shared_ptr<IMemoryManager> memory_manager = nullptr);
+    /** Initialize the function
+     *
+     * @param[in]     input             Input is a 2-D tensor of shape [input_size, batch_size]. Data types supported: F16/F32
+     * @param[in]     weights           Weights tensor of shape [input_size, num_units] that multiplies the input. Data types supported: Same as @p input
+     * @param[in]     recurrent_weights Weights tensor of shape [num_units, num_units] that multiplies the current 'state'. Data types supported: Same as @p input
+     * @param[in]     bias              Bias vector of shape [num_units]. Data types supported: Same as @p input
+     * @param[out]    output            Output tensor of shape [num_units, batch_size]. Data types supported: Same as @p input
+     * @param[in,out] hidden_state      Output tensor of shape [num_units, batch_size]. Data types supported: Same as @p input
+     * @param[in]     info              Activation layer parameter.
+     */
+    void configure(const ICLTensor *input, const ICLTensor *weights, const ICLTensor *recurrent_weights, const ICLTensor *bias, ICLTensor *hidden_state, ICLTensor *output, ActivationLayerInfo &info);
+    /** Initialize the function
+     *
+     * @param[in] input             Input is a 2-D tensor of shape [input_size, batch_size]. Data types supported: F16/F32
+     * @param[in] weights           Weights tensor of shape [input_size, num_units] that multiplies the input. Data types supported: Same as @p input
+     * @param[in] recurrent_weights Weights tensor of shape [num_units, num_units] that multiplies the current 'state'. Data types supported: Same as @p input
+     * @param[in] bias              Bias vector of shape [num_units]. Data types supported: Same as @p input
+     * @param[in] output            Output tensor of shape [num_units, batch_size]. Data types supported: Same as @p input
+     * @param[in] hidden_state      Output tensor of shape [num_units, batch_size]. Data types supported: Same as @p input
+     * @param[in] info              Activation layer parameter.
+     *
+     * @return a status
+     */
+    static Status validate(const ITensorInfo *input, const ITensorInfo *weights, const ITensorInfo *recurrent_weights, const ITensorInfo *bias, const ITensorInfo *hidden_state, const ITensorInfo *output,
+                           const ActivationLayerInfo &info);
+
+    // Inherited methods overridden:
+    void run() override;
+
+private:
+    CLMemoryGroup              _memory_group;
+    CLGEMM                     _gemm_state_f;
+    CLArithmeticAdditionKernel _add_kernel;
+    CLActivationLayerKernel    _activation_kernel;
+    CLFullyConnectedLayer      _fully_connected_kernel;
+    CLCopyKernel               _copy_kernel;
+    CLTensor                   _fully_connected_out;
+    CLTensor                   _gemm_output;
+    CLTensor                   _add_output;
+};
+}
+#endif /* __ARM_COMPUTE_CLRNN_LAYER_H__ */