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>

8 files changed, 375 insertions, 0 deletions

diff --git a/arm_compute/core/CL/CLKernels.h b/arm_compute/core/CL/CLKernels.h
index 2fd2341e48..b767812fc8 100644
--- a/arm_compute/core/CL/CLKernels.h
+++ b/arm_compute/core/CL/CLKernels.h
@@ -64,6 +64,8 @@
 #include "arm_compute/core/CL/kernels/CLElementWiseUnaryLayerKernel.h"
 #include "arm_compute/core/CL/kernels/CLElementwiseOperationKernel.h"
 #include "arm_compute/core/CL/kernels/CLErodeKernel.h"
+#include "arm_compute/core/CL/kernels/CLFFTDigitReverseKernel.h"
+#include "arm_compute/core/CL/kernels/CLFFTRadixStageKernel.h"
 #include "arm_compute/core/CL/kernels/CLFastCornersKernel.h"
 #include "arm_compute/core/CL/kernels/CLFillBorderKernel.h"
 #include "arm_compute/core/CL/kernels/CLFlattenLayerKernel.h"
diff --git a/arm_compute/core/CL/kernels/CLFFTDigitReverseKernel.h b/arm_compute/core/CL/kernels/CLFFTDigitReverseKernel.h
new file mode 100644
index 0000000000..10652cdb4d
--- /dev/null
+++ b/arm_compute/core/CL/kernels/CLFFTDigitReverseKernel.h
@@ -0,0 +1,78 @@
+/*
+ * 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_CLFFTDIGITREVERSEKERNEL_H__
+#define __ARM_COMPUTE_CLFFTDIGITREVERSEKERNEL_H__
+
+#include "arm_compute/core/CL/ICLKernel.h"
+
+namespace arm_compute
+{
+// Forward declarations
+class ICLTensor;
+
+/** Interface for the digit reverse operation kernel. */
+class CLFFTDigitReverseKernel : public ICLKernel
+{
+public:
+    /** Constructor */
+    CLFFTDigitReverseKernel();
+    /** Prevent instances of this class from being copied (As this class contains pointers) */
+    CLFFTDigitReverseKernel(const CLFFTDigitReverseKernel &) = delete;
+    /** Prevent instances of this class from being copied (As this class contains pointers) */
+    CLFFTDigitReverseKernel &operator=(const CLFFTDigitReverseKernel &) = delete;
+    /** Default Move Constructor. */
+    CLFFTDigitReverseKernel(CLFFTDigitReverseKernel &&) = default;
+    /** Default move assignment operator */
+    CLFFTDigitReverseKernel &operator=(CLFFTDigitReverseKernel &&) = default;
+    /** Default destructor */
+    ~CLFFTDigitReverseKernel() = default;
+    /** Set the input and output tensors.
+     *
+     * @param[in]  input  Source tensor. Data types supported: F32.
+     * @param[out] output Destination tensor. Data type supported: same as @p input
+     * @param[in]  idx    Digit reverse index tensor. Data type supported: U32
+     * @param[in]  axis   Axis to perform digit reverse on.
+     */
+    void configure(const ICLTensor *input, ICLTensor *output, const ICLTensor *idx, unsigned int axis);
+    /** Static function to check if given info will lead to a valid configuration of @ref CLFFTDigitReverseKernel
+     *
+     * @param[in] input  Source tensor info. Data types supported: F32.
+     * @param[in] output Destination tensor info. Data type supported: same as @p input
+     * @param[in] idx    Digit reverse index tensor info. Data type supported: U32
+     * @param[in] axis   Axis to perform digit reverse on.
+     *
+     * @return a status
+     */
+    static Status validate(const ITensorInfo *input, const ITensorInfo *output, const ITensorInfo *idx, unsigned int axis);
+
+    // Inherited methods overridden:
+    void run(const Window &window, cl::CommandQueue &queue) override;
+
+private:
+    const ICLTensor *_input;
+    ICLTensor       *_output;
+    const ICLTensor *_idx;
+};
+} // namespace arm_compute
+#endif /*__ARM_COMPUTE_CLFFTDIGITREVERSEKERNEL_H__ */
diff --git a/arm_compute/core/CL/kernels/CLFFTRadixStageKernel.h b/arm_compute/core/CL/kernels/CLFFTRadixStageKernel.h
new file mode 100644
index 0000000000..9de775eafa
--- /dev/null
+++ b/arm_compute/core/CL/kernels/CLFFTRadixStageKernel.h
@@ -0,0 +1,87 @@
+/*
+ * 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_CLFFTRADIXSTAGEKERNEL_H__
+#define __ARM_COMPUTE_CLFFTRADIXSTAGEKERNEL_H__
+
+#include "arm_compute/core/CL/ICLKernel.h"
+
+#include "arm_compute/core/KernelDescriptors.h"
+
+#include <set>
+
+namespace arm_compute
+{
+// Forward declarations
+class ICLTensor;
+
+/** Interface for the FFT radix stage kernel. */
+class CLFFTRadixStageKernel : public ICLKernel
+{
+public:
+    /** Constructor */
+    CLFFTRadixStageKernel();
+    /** Prevent instances of this class from being copied (As this class contains pointers) */
+    CLFFTRadixStageKernel(const CLFFTRadixStageKernel &) = delete;
+    /** Prevent instances of this class from being copied (As this class contains pointers) */
+    CLFFTRadixStageKernel &operator=(const CLFFTRadixStageKernel &) = delete;
+    /** Default Move Constructor. */
+    CLFFTRadixStageKernel(CLFFTRadixStageKernel &&) = default;
+    /** Default move assignment operator */
+    CLFFTRadixStageKernel &operator=(CLFFTRadixStageKernel &&) = default;
+    /** Default destructor */
+    ~CLFFTRadixStageKernel() = default;
+    /** Set the input and output tensors.
+     *
+     * @note If the output tensor is nullptr, the FFT will be performed in-place
+     *
+     * @param[in,out] input  Source tensor. Data types supported: F32.
+     * @param[out]    output Destination tensor. Can be nullptr. Data type supported: same as @p input
+     * @param[in]     config FFT descriptor metadata.
+     */
+    void configure(ICLTensor *input, ICLTensor *output, const FFTRadixStageKernelDescriptor &config);
+    /** Static function to check if given info will lead to a valid configuration of @ref CLFFTRadixStageKernel
+     *
+     * @param[in] input  Source tensor info. Data types supported: F32.
+     * @param[in] output Destination tensor info. Can be nullptr. Data type supported: same as @p input
+     * @param[in] config FFT descriptor metadata.
+     *
+     * @return a status
+     */
+    static Status validate(const ITensorInfo *input, const ITensorInfo *output, const FFTRadixStageKernelDescriptor &config);
+    /** Returns the radix that are support by the FFT kernel
+     *
+     * @return A set of supported radix
+     */
+    static std::set<unsigned int> supported_radix();
+
+    // Inherited methods overridden:
+    void run(const Window &window, cl::CommandQueue &queue) override;
+
+private:
+    ICLTensor *_input;
+    ICLTensor *_output;
+    bool       _run_in_place;
+};
+} // namespace arm_compute
+#endif /*__ARM_COMPUTE_CLFFTRADIXSTAGEKERNEL_H__ */
diff --git a/arm_compute/core/KernelDescriptors.h b/arm_compute/core/KernelDescriptors.h
new file mode 100644
index 0000000000..186dbfb6d8
--- /dev/null
+++ b/arm_compute/core/KernelDescriptors.h
@@ -0,0 +1,38 @@
+/*
+ * 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_CORE_KERNEL_DESCRIPTORS_H__
+#define __ARM_COMPUTE_CORE_KERNEL_DESCRIPTORS_H__
+
+namespace arm_compute
+{
+/** Descriptor used by the FFT core kernels */
+struct FFTRadixStageKernelDescriptor
+{
+    unsigned int axis{ 0 };               /**< Axis to run the FFT on. */
+    unsigned int radix{ 0 };              /**< Radix to use. */
+    unsigned int Nx{ 0 };                 /**< Nx coefficient. */
+    bool         is_first_stage{ false }; /**< Flags if the FFT kernels is the first stage of a decomposed FFT. */
+};
+} // namespace arm_compute
+#endif /* __ARM_COMPUTE_CORE_KERNEL_DESCRIPTORS_H__ */
diff --git a/arm_compute/core/utils/helpers/fft.h b/arm_compute/core/utils/helpers/fft.h
new file mode 100644
index 0000000000..bd84a5c63d
--- /dev/null
+++ b/arm_compute/core/utils/helpers/fft.h
@@ -0,0 +1,55 @@
+/*
+ * 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_UTILS_HELPERS_FFT_H__
+#define __ARM_COMPUTE_UTILS_HELPERS_FFT_H__
+
+#include <set>
+#include <vector>
+
+namespace arm_compute
+{
+namespace helpers
+{
+namespace fft
+{
+/** Decompose a given 1D input size using the provided supported factors.
+ *
+ * @param[in] N                 Input size to be decomposed.
+ * @param[in] supported_factors Supported factors that can be used for decomposition.
+ *
+ * @return A vector with the stages of the decomposition. Will be empty if decomposition failed.
+ */
+std::vector<unsigned int> decompose_stages(unsigned int N, const std::set<unsigned int> &supported_factors);
+/** Calculate digit reverse index vector given fft size and the decomposed stages
+ *
+ * @param N          Input size to calculate digit reverse for
+ * @param fft_stages A vector with the FFT decomposed stages
+ *
+ * @return A vector with the digit reverse indices. Will be empty if it failed.
+ */
+std::vector<unsigned int> digit_reverse_indices(unsigned int N, const std::vector<unsigned int> &fft_stages);
+} // namespace fft
+} // namespace helpers
+} // namespace arm_compute
+#endif /* __ARM_COMPUTE_UTILS_HELPERS_FFT_H__ */
diff --git a/arm_compute/runtime/CL/CLFunctions.h b/arm_compute/runtime/CL/CLFunctions.h
index 42897a6e23..46e43dc0a9 100644
--- a/arm_compute/runtime/CL/CLFunctions.h
+++ b/arm_compute/runtime/CL/CLFunctions.h
@@ -65,6 +65,7 @@
 #include "arm_compute/runtime/CL/functions/CLElementwiseOperations.h"
 #include "arm_compute/runtime/CL/functions/CLEqualizeHistogram.h"
 #include "arm_compute/runtime/CL/functions/CLErode.h"
+#include "arm_compute/runtime/CL/functions/CLFFT1D.h"
 #include "arm_compute/runtime/CL/functions/CLFastCorners.h"
 #include "arm_compute/runtime/CL/functions/CLFillBorder.h"
 #include "arm_compute/runtime/CL/functions/CLFlattenLayer.h"
diff --git a/arm_compute/runtime/CL/functions/CLFFT1D.h b/arm_compute/runtime/CL/functions/CLFFT1D.h
new file mode 100644
index 0000000000..1612cf7f50
--- /dev/null
+++ 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__ */
diff --git a/arm_compute/runtime/FunctionDescriptors.h b/arm_compute/runtime/FunctionDescriptors.h
new file mode 100644
index 0000000000..7ff25019e6
--- /dev/null
+++ b/arm_compute/runtime/FunctionDescriptors.h
@@ -0,0 +1,35 @@
+/*
+ * 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_RUNTIME_FUNCTION_DESCRIPTORS_H__
+#define __ARM_COMPUTE_RUNTIME_FUNCTION_DESCRIPTORS_H__
+
+namespace arm_compute
+{
+/** Descriptor used by the FFT1d function */
+struct FFT1DInfo
+{
+    unsigned int axis{ 0 }; /**< Axis to run the FFT on. */
+};
+} // namespace arm_compute
+#endif /* __ARM_COMPUTE_RUNTIME_FUNCTION_DESCRIPTORS_H__ */