COMPMID-1726: Implement CLUnstack.

Change-Id: I94b0707d19757c5f5d7ca66d9c47e378867126a3
Reviewed-on: https://review.mlplatform.org/325
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: Georgios Pinitas <georgios.pinitas@arm.com>

3 files changed, 84 insertions, 0 deletions

diff --git a/arm_compute/core/utils/misc/ShapeCalculator.h b/arm_compute/core/utils/misc/ShapeCalculator.h
index adf5309ea5..4756ff4f97 100644
--- a/arm_compute/core/utils/misc/ShapeCalculator.h
+++ b/arm_compute/core/utils/misc/ShapeCalculator.h
@@ -803,6 +803,13 @@ inline TensorShape extract_shape(const TensorShape *data)
     return *data;
 }
 
+inline TensorShape calculate_unstack_shape(TensorShape input_shape, unsigned int axis)
+{
+    ARM_COMPUTE_ERROR_ON(axis > input_shape.num_dimensions());
+    input_shape.remove_dimension(axis);
+    return input_shape;
+}
+
 template <typename T>
 inline TensorShape calculate_depth_concatenate_shape(const std::vector<T *> &inputs_vector)
 {
diff --git a/arm_compute/runtime/CL/CLFunctions.h b/arm_compute/runtime/CL/CLFunctions.h
index 303a8989a9..e0cf65b923 100644
--- a/arm_compute/runtime/CL/CLFunctions.h
+++ b/arm_compute/runtime/CL/CLFunctions.h
@@ -134,6 +134,7 @@
 #include "arm_compute/runtime/CL/functions/CLThreshold.h"
 #include "arm_compute/runtime/CL/functions/CLTile.h"
 #include "arm_compute/runtime/CL/functions/CLTranspose.h"
+#include "arm_compute/runtime/CL/functions/CLUnstack.h"
 #include "arm_compute/runtime/CL/functions/CLUpsampleLayer.h"
 #include "arm_compute/runtime/CL/functions/CLWarpAffine.h"
 #include "arm_compute/runtime/CL/functions/CLWarpPerspective.h"
diff --git a/arm_compute/runtime/CL/functions/CLUnstack.h b/arm_compute/runtime/CL/functions/CLUnstack.h
new file mode 100644
index 0000000000..feed430c58
--- /dev/null
+++ b/arm_compute/runtime/CL/functions/CLUnstack.h
@@ -0,0 +1,76 @@
+/*
+ * 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_CLUNSTACK_H__
+#define __ARM_COMPUTE_CLUNSTACK_H__
+
+#include "arm_compute/core/CL/OpenCL.h"
+#include "arm_compute/core/Types.h"
+#include "arm_compute/runtime/IFunction.h"
+
+#include "arm_compute/runtime/CL/functions/CLStridedSlice.h"
+
+#include <memory>
+
+namespace arm_compute
+{
+class ICLTensor;
+
+/** Basic function to unpack a rank-R tensor into rank-(R-1) tensors. This function calls the following functions:
+ *
+ * -# @ref CLStridedSlice
+ *
+ */
+class CLUnstack : public IFunction
+{
+public:
+    /** Default constructor */
+    CLUnstack();
+    /** Set the input, output and unstacking axis.
+     *
+     * @param[in]     input         A tensor to be unstacked. Data type supported: U8/S8/QASYMM8/U16/S16/U32/S32/F16/F32.
+     * @param[in,out] output_vector A vector of tensors. Data types supported: Same as @p input.
+     *                              Note: The number of elements of the vector will be used as the number of slices to be taken from the axis.
+     * @param[in]     axis          The axis to unstack along. Valid values are [-R,R) where R is the input's rank. Negative values wrap around.
+     *
+     */
+    void configure(const ICLTensor *input, const std::vector<ICLTensor *> &output_vector, int axis);
+    /** Static function to check if given info will lead to a valid configuration of @ref CLUnstack
+     *
+     * @param[in] input         Input tensor info. Data type supported: U8/S8/QASYMM8/U16/S16/U32/S32/F16/F32
+     * @param[in] output_vector Vector of output tensors' info. Data types supported: Same as @p input.
+     * @param[in] axis          The axis to unstack along. Valid values are [-R,R) where R is the input's rank. Negative values wrap around.
+     *
+     * @return a status
+     */
+    static Status validate(const ITensorInfo *input, const std::vector<ITensorInfo *> &output_vector, int axis);
+
+    // Inherited methods overridden:
+    void run() override;
+
+private:
+    unsigned int                      _num_slices;
+    std::unique_ptr<CLStridedSlice[]> _strided_slice_vector;
+};
+} // namespace arm_compute
+#endif /* __ARM_COMPUTE_CLUNSTACK_H__ */