COMPMID-1958: Implements 1D FFT in OpenCL.

Forward complex FFT implementation.

Change-Id: Ia0ba8740072e5adb06f8ead462a47abc8b5dd125
Signed-off-by: Georgios Pinitas <georgios.pinitas@arm.com>
Reviewed-on: https://review.mlplatform.org/c/904
Reviewed-by: Gian Marco Iodice <gianmarco.iodice@arm.com>
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
diff --git a/arm_compute/runtime/CL/functions/CLFFT1D.h b/arm_compute/runtime/CL/functions/CLFFT1D.h
new file mode 100644
index 0000000..1612cf7
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+++ b/arm_compute/runtime/CL/functions/CLFFT1D.h
@@ -0,0 +1,79 @@
+/*
+ * Copyright (c) 2019 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_CLFFT1D_H__
+#define __ARM_COMPUTE_CLFFT1D_H__
+
+#include "arm_compute/runtime/IFunction.h"
+
+#include "arm_compute/core/CL/kernels/CLFFTDigitReverseKernel.h"
+#include "arm_compute/core/CL/kernels/CLFFTRadixStageKernel.h"
+#include "arm_compute/runtime/CL/CLMemoryGroup.h"
+#include "arm_compute/runtime/CL/CLTensor.h"
+#include "arm_compute/runtime/FunctionDescriptors.h"
+
+namespace arm_compute
+{
+// Forward declaration
+class ICLTensor;
+
+/** Basic function to execute one dimensional FFT. This function calls the following OpenCL kernels:
+ *
+ * -# @ref CLFFTDigitReverseKernel Performs digit reverse
+ * -# @ref CLFFTRadixStageKernel   A list of FFT kernels depending on the radix decomposition
+ */
+class CLFFT1D : public IFunction
+{
+public:
+    /** Default Constructor */
+    CLFFT1D(std::shared_ptr<IMemoryManager> memory_manager = nullptr);
+    /** Initialise the function's source, destinations and border mode.
+     *
+     * @param[in]  input  Source tensor. Data types supported: F32.
+     * @param[out] output Destination tensor. Data types and data layouts supported: Same as @p input.
+     * @param[in]  config FFT related configuration
+     */
+    void configure(const ICLTensor *input, ICLTensor *output, const FFT1DInfo &config);
+    /** Static function to check if given info will lead to a valid configuration of @ref CLFFT1D.
+     *
+     * @param[in] input  Source tensor info. Data types supported: F32.
+     * @param[in] output Destination tensor info. Data types and data layouts supported: Same as @p input.
+     * @param[in] config FFT related configuration
+     *
+     * @return a status
+     */
+    static Status validate(const ITensorInfo *input, const ITensorInfo *output, const FFT1DInfo &config);
+
+    // Inherited methods overridden:
+    void run() override;
+
+protected:
+    CLMemoryGroup                            _memory_group;
+    CLTensor                                 _digit_reversed_input;
+    CLTensor                                 _digit_reverse_indices;
+    CLFFTDigitReverseKernel                  _digit_reverse_kernel;
+    std::unique_ptr<CLFFTRadixStageKernel[]> _fft_kernels;
+    unsigned int                             _num_ffts;
+};
+} // namespace arm_compute
+#endif /*__ARM_COMPUTE_CLFFT1D_H__ */