COMPMID-1023: Import memory for OpenCL

Change-Id: I201bc00a1261814737e6b6878ecfe9904bae0cc1
Reviewed-on: https://eu-gerrit-1.euhpc.arm.com/128212
Tested-by: Jenkins <bsgcomp@arm.com>
Reviewed-by: Anthony Barbier <anthony.barbier@arm.com>
diff --git a/arm_compute/runtime/CL/CLMemoryRegion.h b/arm_compute/runtime/CL/CLMemoryRegion.h
new file mode 100644
index 0000000..01dd54e
--- /dev/null
+++ b/arm_compute/runtime/CL/CLMemoryRegion.h
@@ -0,0 +1,178 @@
+/*
+ * 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_RUNTIME_CL_CL_MEMORY_REGION_H__
+#define __ARM_COMPUTE_RUNTIME_CL_CL_MEMORY_REGION_H__
+
+#include "arm_compute/core/CL/OpenCL.h"
+#include "arm_compute/runtime/IMemoryRegion.h"
+
+#include <cstddef>
+
+namespace arm_compute
+{
+/** OpenCL memory region interface */
+class ICLMemoryRegion : public IMemoryRegion
+{
+public:
+    /** Constructor
+     *
+     * @param[in] ctx  OpenCL context
+     * @param[in] size Region size
+     */
+    ICLMemoryRegion(cl::Context ctx, size_t size);
+    /** Default Destructor */
+    virtual ~ICLMemoryRegion() = default;
+    /** Prevent instances of this class from being copied (As this class contains pointers) */
+    ICLMemoryRegion(const ICLMemoryRegion &) = delete;
+    /** Default move constructor */
+    ICLMemoryRegion(ICLMemoryRegion &&) = default;
+    /** Prevent instances of this class from being copied (As this class contains pointers) */
+    ICLMemoryRegion &operator=(const ICLMemoryRegion &) = delete;
+    /** Default move assignment operator */
+    ICLMemoryRegion &operator=(ICLMemoryRegion &&) = default;
+    /** Returns the underlying CL buffer
+     *
+     * @return CL memory buffer object
+     */
+    const cl::Buffer &cl_data() const;
+    /** Host/SVM pointer accessor
+     *
+     * @return Host/SVM pointer base
+     */
+    virtual void *ptr() = 0;
+    /** Enqueue a map operation of the allocated buffer on the given queue.
+     *
+     * @param[in,out] q        The CL command queue to use for the mapping operation.
+     * @param[in]     blocking If true, then the mapping will be ready to use by the time
+     *                         this method returns, else it is the caller's responsibility
+     *                         to flush the queue and wait for the mapping operation to have completed before using the returned mapping pointer.
+     *
+     * @return The mapping address.
+     */
+    virtual void *map(cl::CommandQueue &q, bool blocking) = 0;
+    /** Enqueue an unmap operation of the allocated buffer on the given queue.
+     *
+     * @note This method simply enqueue the unmap operation, it is the caller's responsibility to flush the queue and make sure the unmap is finished before
+     *       the memory is accessed by the device.
+     *
+     * @param[in,out] q The CL command queue to use for the mapping operation.
+     */
+    virtual void unmap(cl::CommandQueue &q) = 0;
+
+    // Inherited methods overridden :
+    void *buffer() override;
+    void *buffer() const override;
+    void **handle() override;
+
+protected:
+    cl::Context _ctx;
+    void       *_mapping;
+    cl::Buffer  _mem;
+};
+
+/** OpenCL buffer memory region implementation */
+class CLBufferMemoryRegion final : public ICLMemoryRegion
+{
+public:
+    /** Constructor
+     *
+     * @param[in] ctx   OpenCL context
+     * @param[in] flags Memory flags
+     * @param[in] size  Region size
+     */
+    CLBufferMemoryRegion(cl::Context ctx, cl_mem_flags flags, size_t size);
+
+    // Inherited methods overridden :
+    void *ptr() override;
+    void *map(cl::CommandQueue &q, bool blocking) override;
+    void unmap(cl::CommandQueue &q) override;
+};
+
+/** OpenCL SVM memory region interface */
+class ICLSVMMemoryRegion : public ICLMemoryRegion
+{
+protected:
+    /** Constructor
+     *
+     * @param[in] ctx       OpenCL context
+     * @param[in] flags     Memory flags
+     * @param[in] size      Region size
+     * @param[in] alignment Alignment
+     */
+    ICLSVMMemoryRegion(cl::Context ctx, cl_mem_flags flags, size_t size, size_t alignment);
+    /** Destructor */
+    virtual ~ICLSVMMemoryRegion();
+    /** Prevent instances of this class from being copied (As this class contains pointers) */
+    ICLSVMMemoryRegion(const ICLSVMMemoryRegion &) = delete;
+    /** Default move constructor */
+    ICLSVMMemoryRegion(ICLSVMMemoryRegion &&) = default;
+    /** Prevent instances of this class from being copied (As this class contains pointers) */
+    ICLSVMMemoryRegion &operator=(const ICLSVMMemoryRegion &) = delete;
+    /** Default move assignment operator */
+    ICLSVMMemoryRegion &operator=(ICLSVMMemoryRegion &&) = default;
+
+    // Inherited methods overridden :
+    void *ptr() override;
+
+protected:
+    void *_ptr;
+};
+
+/** OpenCL coarse-grain SVM memory region implementation */
+class CLCoarseSVMMemoryRegion final : public ICLSVMMemoryRegion
+{
+public:
+    /** Constructor
+     *
+     * @param[in] ctx       OpenCL context
+     * @param[in] flags     Memory flags
+     * @param[in] size      Region size
+     * @param[in] alignment Alignment
+     */
+    CLCoarseSVMMemoryRegion(cl::Context ctx, cl_mem_flags flags, size_t size, size_t alignment);
+
+    // Inherited methods overridden :
+    void *map(cl::CommandQueue &q, bool blocking) override;
+    void unmap(cl::CommandQueue &q) override;
+};
+
+/** OpenCL fine-grain SVM memory region implementation */
+class CLFineSVMMemoryRegion final : public ICLSVMMemoryRegion
+{
+public:
+    /** Constructor
+     *
+     * @param[in] ctx       OpenCL context
+     * @param[in] flags     Memory flags
+     * @param[in] size      Region size
+     * @param[in] alignment Alignment
+     */
+    CLFineSVMMemoryRegion(cl::Context ctx, cl_mem_flags flags, size_t size, size_t alignment);
+
+    // Inherited methods overridden :
+    void *map(cl::CommandQueue &q, bool blocking) override;
+    void unmap(cl::CommandQueue &q) override;
+};
+} // namespace arm_compute
+#endif /* __ARM_COMPUTE_RUNTIME_CL_CL_MEMORY_REGION_H__ */