COMPMID-1381: Cleaned up the AssemblyHelper interface

Introduced a new IFunction for when we'll fork the arm_gemm functions
Increased encapsulation and abstraction of which method is used

Change-Id: I5fd8b14b5c77e7f8ecb09029b5e2eccd10dbdcf4
Reviewed-on: https://eu-gerrit-1.euhpc.arm.com/139108
Tested-by: Jenkins <bsgcomp@arm.com>
Reviewed-by: Georgios Pinitas <georgios.pinitas@arm.com>
Reviewed-by: Pablo Tello <pablo.tello@arm.com>
diff --git a/arm_compute/core/NEON/kernels/assembly/NEGEMMAssemblyWrapperKernel.h b/arm_compute/core/NEON/kernels/assembly/NEGEMMAssemblyWrapperKernel.h
new file mode 100644
index 0000000..9eaf606
--- /dev/null
+++ b/arm_compute/core/NEON/kernels/assembly/NEGEMMAssemblyWrapperKernel.h
@@ -0,0 +1,93 @@
+/*
+ * 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_ASSEMBLY_GEMM_KERNEL_WRAPPER_KERNEL_H__
+#define __ARM_COMPUTE_ASSEMBLY_GEMM_KERNEL_WRAPPER_KERNEL_H__
+
+#include "arm_compute/core/NEON/INEKernel.h"
+#include "arm_compute/core/Validate.h"
+#include "arm_compute/core/Utils.h"
+
+#include "gemm_common.hpp"
+
+namespace arm_compute
+{
+class ITensor;
+
+/** This class is a wrapper for the assembly kernels.
+  *
+  * Some kernels were written in assembly and highly optimised for specific CPUs like A53 or A55.
+  * This class works as a wrapper for these assembly kernels. The arm compute library creates an instance
+  * of NEGEMMAssemblyWrapperKernel and other auxiliary data structures to execute a single assembly kernel
+  * in the context of an NEFunctions.
+  *
+  * The type T is the type of the actual kernel implemented in assembly which is of type
+  *         template<typename To, typename Tr> class GemmCommon
+  *
+  *
+  */
+template <typename TypeInput, typename TypeOutput>
+class NEGEMMAssemblyWrapperKernel final : public INEKernel
+{
+public:
+    /** Constructor
+     */
+    NEGEMMAssemblyWrapperKernel() : _kernel(nullptr) {}
+
+    NEGEMMAssemblyWrapperKernel(NEGEMMAssemblyWrapperKernel &) = delete;
+    NEGEMMAssemblyWrapperKernel(NEGEMMAssemblyWrapperKernel &&) = default;
+    NEGEMMAssemblyWrapperKernel & operator=(NEGEMMAssemblyWrapperKernel &) = delete;
+
+    const char *name() const override
+    {
+        return "NEGEMMAssemblyWrapperKernel";
+    }
+    // Inherited methods overridden:
+    void run(const Window &window, const ThreadInfo &info) override
+    {
+        ARM_COMPUTE_ERROR_ON_NULLPTR((reinterpret_cast<void*>(_kernel)));
+        ARM_COMPUTE_ERROR_ON_UNCONFIGURED_KERNEL(this);
+        auto first = window.x().start();
+        auto last  = window.x().end();
+        _kernel->execute(first, last, info.thread_id);
+    }
+    /** Initialise the kernel's input and output.
+     *
+     * @param[in] kernel      Pointer to an assembly kernel implementation.
+     * @param[in] num_threads Number of concurrent threads which will execute the kernel.
+     */
+    void configure(arm_gemm::GemmCommon<TypeInput, TypeOutput> *kernel)
+    {
+        ARM_COMPUTE_ERROR_ON_NULLPTR((reinterpret_cast<void*>(kernel)));
+        _kernel = kernel;
+        auto   win_last = _kernel->get_window_size();
+        Window win;
+        win.set(Window::DimX, Window::Dimension(0, win_last, 1));
+        INEKernel::configure(win);
+    }
+private:
+    arm_gemm::GemmCommon<TypeInput, TypeOutput>* _kernel;
+};
+
+} // namespace arm_compute
+#endif /* __ARM_COMPUTE_ASSEMBLY_GEMM_KERNEL_WRAPPER_KERNEL_H__ */