COMPMID-1088: Use IMemoryRegion in interfaces where possible

-Simplifies import memory interface
-Changes the used of void** handles with appropriate interfaces.

Change-Id: I5918c855c11f46352058864623336b352162a4b7
diff --git a/arm_compute/runtime/GLES_COMPUTE/GCMemory.h b/arm_compute/runtime/GLES_COMPUTE/GCMemory.h
new file mode 100644
index 0000000..bf0428a
--- /dev/null
+++ b/arm_compute/runtime/GLES_COMPUTE/GCMemory.h
@@ -0,0 +1,85 @@
+/*
+ * 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_GLES_COMPUTE_GCMEMORY_H__
+#define __ARM_COMPUTE_RUNTIME_GLES_COMPUTE_GCMEMORY_H__
+
+#include "arm_compute/runtime/IMemory.h"
+
+#include "arm_compute/runtime/GLES_COMPUTE/GCMemoryRegion.h"
+
+#include <cstddef>
+#include <memory>
+
+namespace arm_compute
+{
+/** GLES implementation of memory object */
+class GCMemory : public IMemory
+{
+public:
+    /** Default Constructor */
+    GCMemory();
+    /** Default Constructor
+     *
+     * @param[in] memory Memory to be imported
+     */
+    GCMemory(std::shared_ptr<IGCMemoryRegion> memory);
+    /** Default Constructor
+     *
+     * @note Ownership of the memory is not transferred to this object.
+     *       Thus management (allocate/free) should be done by the client.
+     *
+     * @param[in] memory Memory to be imported
+     */
+    GCMemory(IGCMemoryRegion *memory);
+    /** Allow instances of this class to be copied */
+    GCMemory(const GCMemory &) = default;
+    /** Allow instances of this class to be copy assigned */
+    GCMemory &operator=(const GCMemory &) = default;
+    /** Allow instances of this class to be moved */
+    GCMemory(GCMemory &&) noexcept = default;
+    /** Allow instances of this class to be move assigned */
+    GCMemory &operator=(GCMemory &&) noexcept = default;
+    /** GLES Region accessor
+     *
+     * @return Memory region
+     */
+    IGCMemoryRegion *gc_region();
+    /** GLES Region accessor
+     *
+     * @return Memory region
+     */
+    IGCMemoryRegion *gc_region() const;
+
+    // Inherited methods overridden:
+    IMemoryRegion *region() final;
+    IMemoryRegion *region() const final;
+    void set_region(IMemoryRegion *region) final;
+    void set_owned_region(std::unique_ptr<IMemoryRegion> region) final;
+
+private:
+    IGCMemoryRegion                 *_region;
+    std::shared_ptr<IGCMemoryRegion> _region_owned;
+};
+} // namespace arm_compute
+#endif /* __ARM_COMPUTE_RUNTIME_GLES_COMPUTE_GCMEMORY_H__ */
diff --git a/arm_compute/runtime/GLES_COMPUTE/GCMemoryRegion.h b/arm_compute/runtime/GLES_COMPUTE/GCMemoryRegion.h
new file mode 100644
index 0000000..23e3ceb
--- /dev/null
+++ b/arm_compute/runtime/GLES_COMPUTE/GCMemoryRegion.h
@@ -0,0 +1,108 @@
+/*
+ * 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_GLES_COMPUTE_GC_MEMORY_REGION_H__
+#define __ARM_COMPUTE_RUNTIME_GLES_COMPUTE_GC_MEMORY_REGION_H__
+
+#include "arm_compute/core/GLES_COMPUTE/OpenGLES.h"
+#include "arm_compute/runtime/IMemoryRegion.h"
+
+#include <cstddef>
+
+namespace arm_compute
+{
+/** GLES memory region interface */
+class IGCMemoryRegion : public IMemoryRegion
+{
+public:
+    /** Constructor
+     *
+     * @param[in] size Region size
+     */
+    IGCMemoryRegion(size_t size);
+    /** Default Destructor */
+    virtual ~IGCMemoryRegion() = default;
+    /** Prevent instances of this class from being copied (As this class contains pointers) */
+    IGCMemoryRegion(const IGCMemoryRegion &) = delete;
+    /** Default move constructor */
+    IGCMemoryRegion(IGCMemoryRegion &&) = default;
+    /** Prevent instances of this class from being copied (As this class contains pointers) */
+    IGCMemoryRegion &operator=(const IGCMemoryRegion &) = delete;
+    /** Default move assignment operator */
+    IGCMemoryRegion &operator=(IGCMemoryRegion &&) = default;
+    /** Returns the underlying CL buffer
+     *
+     * @return CL memory buffer object
+     */
+    const GLuint &gc_ssbo_name() 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] 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(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.
+     *
+     */
+    virtual void unmap() = 0;
+
+    // Inherited methods overridden :
+    void *buffer() override;
+    void *buffer() const override;
+
+protected:
+    void *_mapping;
+    GLuint _ssbo_name;
+};
+
+/** GLES buffer memory region implementation */
+class GCBufferMemoryRegion final : public IGCMemoryRegion
+{
+public:
+    /** Constructor
+     *
+     * @param[in] size Region size
+     */
+    GCBufferMemoryRegion(size_t size);
+    /** Destructor */
+    ~GCBufferMemoryRegion();
+
+    // Inherited methods overridden :
+    void *ptr() final;
+    void *map(bool blocking) final;
+    void                           unmap() final;
+    std::unique_ptr<IMemoryRegion> extract_subregion(size_t offset, size_t size) final;
+};
+} // namespace arm_compute
+#endif /* __ARM_COMPUTE_RUNTIME_GLES_COMPUTE_GC_MEMORY_REGION_H__ */
diff --git a/arm_compute/runtime/GLES_COMPUTE/GCTensorAllocator.h b/arm_compute/runtime/GLES_COMPUTE/GCTensorAllocator.h
index 1bd3582..b706766 100644
--- a/arm_compute/runtime/GLES_COMPUTE/GCTensorAllocator.h
+++ b/arm_compute/runtime/GLES_COMPUTE/GCTensorAllocator.h
@@ -26,6 +26,7 @@
 #define __ARM_COMPUTE_GCTENSORALLOCATOR_H__
 
 #include "arm_compute/core/GLES_COMPUTE/OpenGLES.h"
+#include "arm_compute/runtime/GLES_COMPUTE/GCMemory.h"
 #include "arm_compute/runtime/ITensorAllocator.h"
 #include "arm_compute/runtime/MemoryGroupBase.h"
 
@@ -38,20 +39,6 @@
 class MemoryGroupBase;
 using GCMemoryGroup = MemoryGroupBase<GCTensor>;
 
-class GLBufferWrapper
-{
-public:
-    GLBufferWrapper()
-        : _ssbo_name(0)
-    {
-        ARM_COMPUTE_GL_CHECK(glGenBuffers(1, &_ssbo_name));
-    }
-    ~GLBufferWrapper()
-    {
-        ARM_COMPUTE_GL_CHECK(glDeleteBuffers(1, &_ssbo_name));
-    }
-    GLuint _ssbo_name;
-};
 /** Basic implementation of a GLES memory tensor allocator. */
 class GCTensorAllocator : public ITensorAllocator
 {
@@ -72,7 +59,7 @@
     GCTensorAllocator &operator=(GCTensorAllocator &&) = default;
 
     /** Default destructor */
-    ~GCTensorAllocator();
+    ~GCTensorAllocator() = default;
 
     /** Interface to be implemented by the child class to return the pointer to the mapped data.
      *
@@ -135,11 +122,10 @@
     void unlock() override;
 
 private:
-    GCMemoryGroup                   *_associated_memory_group; /**< Registered memory group */
-    std::unique_ptr<GLBufferWrapper> _gl_buffer;               /**< OpenGL ES object containing the tensor data. */
-    uint8_t                         *_mapping;                 /**< Pointer to the CPU mapping of the OpenGL ES buffer. */
-    GCTensor                        *_owner;                   /**< Owner of the allocator */
+    GCMemoryGroup *_associated_memory_group; /**< Registered memory group */
+    GCMemory       _memory;                  /**< OpenGL ES memory */
+    uint8_t       *_mapping;                 /**< Pointer to the CPU mapping of the OpenGL ES buffer. */
+    GCTensor      *_owner;                   /**< Owner of the allocator */
 };
-}
-
+} // namespace arm_compute
 #endif /* __ARM_COMPUTE_GCTENSORALLOCATOR_H__ */