COMPMID-1088: Use IMemoryRegion in interfaces where possible

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

Change-Id: I5918c855c11f46352058864623336b352162a4b7

13 files changed, 326 insertions, 125 deletions

diff --git a/src/core/CL/OpenCL.cpp b/src/core/CL/OpenCL.cpp
index 486bb6a1bd..6725f36a5d 100644
--- a/src/core/CL/OpenCL.cpp
+++ b/src/core/CL/OpenCL.cpp
@@ -106,6 +106,7 @@ bool CLSymbols::load(const std::string &library)
     LOAD_FUNCTION_PTR(clReleaseMemObject, handle);
     LOAD_FUNCTION_PTR(clGetDeviceInfo, handle);
     LOAD_FUNCTION_PTR(clGetDeviceIDs, handle);
+    LOAD_FUNCTION_PTR(clGetMemObjectInfo, handle);
     LOAD_FUNCTION_PTR(clRetainEvent, handle);
     LOAD_FUNCTION_PTR(clGetPlatformIDs, handle);
     LOAD_FUNCTION_PTR(clGetKernelWorkGroupInfo, handle);
@@ -796,6 +797,24 @@ cl_int clGetDeviceInfo(cl_device_id   device,
     }
 }
 
+cl_int clGetMemObjectInfo(cl_mem      memobj,
+                          cl_mem_info param_name,
+                          size_t      param_value_size,
+                          void       *param_value,
+                          size_t     *param_value_size_ret)
+{
+    arm_compute::CLSymbols::get().load_default();
+    auto func = arm_compute::CLSymbols::get().clGetMemObjectInfo_ptr;
+    if(func != nullptr)
+    {
+        return func(memobj, param_name, param_value_size, param_value, param_value_size_ret);
+    }
+    else
+    {
+        return CL_OUT_OF_RESOURCES;
+    }
+}
+
 cl_int clRetainEvent(cl_event event)
 {
     arm_compute::CLSymbols::get().load_default();
diff --git a/src/runtime/BlobMemoryPool.cpp b/src/runtime/BlobMemoryPool.cpp
index 29505e57fc..e09451cd62 100644
--- a/src/runtime/BlobMemoryPool.cpp
+++ b/src/runtime/BlobMemoryPool.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017 ARM Limited.
+ * Copyright (c) 2017-2018 ARM Limited.
  *
  * SPDX-License-Identifier: MIT
  *
@@ -52,7 +52,7 @@ void BlobMemoryPool::acquire(MemoryMappings &handles)
     for(auto &handle : handles)
     {
         ARM_COMPUTE_ERROR_ON(handle.first == nullptr);
-        *handle.first = _blobs[handle.second];
+        handle.first->set_region(_blobs[handle.second].get());
     }
 }
 
@@ -61,7 +61,7 @@ void BlobMemoryPool::release(MemoryMappings &handles)
     for(auto &handle : handles)
     {
         ARM_COMPUTE_ERROR_ON(handle.first == nullptr);
-        *handle.first = nullptr;
+        handle.first->set_region(nullptr);
     }
 }
 
@@ -82,17 +82,11 @@ void BlobMemoryPool::allocate_blobs(const std::vector<size_t> &sizes)
 
     for(const auto &size : sizes)
     {
-        _blobs.push_back(_allocator->allocate(size, 0));
+        _blobs.push_back(_allocator->make_region(size, 0));
     }
 }
 
 void BlobMemoryPool::free_blobs()
 {
-    ARM_COMPUTE_ERROR_ON(!_allocator);
-
-    for(auto &blob : _blobs)
-    {
-        _allocator->free(blob);
-    }
     _blobs.clear();
 }
\ No newline at end of file
diff --git a/src/runtime/CL/CLMemory.cpp b/src/runtime/CL/CLMemory.cpp
index bbc513d783..5bea85cfae 100644
--- a/src/runtime/CL/CLMemory.cpp
+++ b/src/runtime/CL/CLMemory.cpp
@@ -24,23 +24,20 @@
 #include "arm_compute/runtime/CL/CLMemory.h"
 
 #include "arm_compute/core/Error.h"
+#include "arm_compute/core/utils/misc/Cast.h"
 
 namespace arm_compute
 {
 CLMemory::CLMemory()
     : _region(nullptr), _region_owned(nullptr)
 {
-    create_empty_region();
 }
 
 CLMemory::CLMemory(std::shared_ptr<ICLMemoryRegion> memory)
     : _region(nullptr), _region_owned(std::move(memory))
 {
-    if(_region_owned == nullptr)
-    {
-        create_empty_region();
-    }
-    _region = _region_owned.get();
+    _region_owned = memory;
+    _region       = _region_owned.get();
 }
 
 CLMemory::CLMemory(ICLMemoryRegion *memory)
@@ -49,19 +46,36 @@ CLMemory::CLMemory(ICLMemoryRegion *memory)
     _region = memory;
 }
 
-ICLMemoryRegion *CLMemory::region()
+ICLMemoryRegion *CLMemory::cl_region()
+{
+    return _region;
+}
+
+ICLMemoryRegion *CLMemory::cl_region() const
+{
+    return _region;
+}
+
+IMemoryRegion *CLMemory::region()
 {
     return _region;
 }
 
-ICLMemoryRegion *CLMemory::region() const
+IMemoryRegion *CLMemory::region() const
 {
     return _region;
 }
 
-void CLMemory::create_empty_region()
+void CLMemory::set_region(IMemoryRegion *region)
+{
+    auto cl_region = utils::cast::polymorphic_downcast<ICLMemoryRegion *>(region);
+    _region_owned  = nullptr;
+    _region        = cl_region;
+}
+
+void CLMemory::set_owned_region(std::unique_ptr<IMemoryRegion> region)
 {
-    _region_owned = std::make_shared<CLBufferMemoryRegion>(cl::Context(), CL_MEM_ALLOC_HOST_PTR | CL_MEM_READ_WRITE, 0);
+    _region_owned = utils::cast::polymorphic_downcast_unique_ptr<ICLMemoryRegion>(std::move(region));
     _region       = _region_owned.get();
 }
 } // namespace arm_compute
\ No newline at end of file
diff --git a/src/runtime/CL/CLMemoryRegion.cpp b/src/runtime/CL/CLMemoryRegion.cpp
index 15fd7f333e..9578d73934 100644
--- a/src/runtime/CL/CLMemoryRegion.cpp
+++ b/src/runtime/CL/CLMemoryRegion.cpp
@@ -48,9 +48,10 @@ void *ICLMemoryRegion::buffer() const
     return _mapping;
 }
 
-void **ICLMemoryRegion::handle()
+std::unique_ptr<IMemoryRegion> ICLMemoryRegion::extract_subregion(size_t offset, size_t size)
 {
-    return reinterpret_cast<void **>(&_mem);
+    ARM_COMPUTE_UNUSED(offset, size);
+    return nullptr;
 }
 
 CLBufferMemoryRegion::CLBufferMemoryRegion(cl::Context ctx, cl_mem_flags flags, size_t size)
@@ -62,6 +63,12 @@ CLBufferMemoryRegion::CLBufferMemoryRegion(cl::Context ctx, cl_mem_flags flags,
     }
 }
 
+CLBufferMemoryRegion::CLBufferMemoryRegion(const cl::Buffer &buffer)
+    : ICLMemoryRegion(buffer.getInfo<CL_MEM_CONTEXT>(), buffer.getInfo<CL_MEM_SIZE>())
+{
+    _mem = buffer;
+}
+
 void *CLBufferMemoryRegion::ptr()
 {
     return nullptr;
diff --git a/src/runtime/CL/CLTensorAllocator.cpp b/src/runtime/CL/CLTensorAllocator.cpp
index dd716f77ff..0307498335 100644
--- a/src/runtime/CL/CLTensorAllocator.cpp
+++ b/src/runtime/CL/CLTensorAllocator.cpp
@@ -28,86 +28,87 @@
 #include "arm_compute/runtime/CL/CLMemoryGroup.h"
 #include "arm_compute/runtime/CL/CLScheduler.h"
 
-using namespace arm_compute;
+namespace arm_compute
+{
+const cl::Buffer CLTensorAllocator::_empty_buffer = cl::Buffer();
 
 namespace
 {
-std::shared_ptr<arm_compute::ICLMemoryRegion> allocate_region(cl::Context context, size_t size, cl_uint alignment)
+std::unique_ptr<ICLMemoryRegion> allocate_region(cl::Context context, size_t size, cl_uint alignment)
 {
     // Try fine-grain SVM
-    std::shared_ptr<ICLMemoryRegion> region = std::make_shared<CLFineSVMMemoryRegion>(context, CL_MEM_READ_WRITE | CL_MEM_SVM_FINE_GRAIN_BUFFER, size, alignment);
+    std::unique_ptr<ICLMemoryRegion> region = support::cpp14::make_unique<CLFineSVMMemoryRegion>(context,
+                                                                                                 CL_MEM_READ_WRITE | CL_MEM_SVM_FINE_GRAIN_BUFFER,
+                                                                                                 size,
+                                                                                                 alignment);
 
     // Try coarse-grain SVM in case of failure
     if(region != nullptr && region->ptr() == nullptr)
     {
-        region = std::make_shared<CLCoarseSVMMemoryRegion>(context, CL_MEM_READ_WRITE, size, alignment);
+        region = support::cpp14::make_unique<CLCoarseSVMMemoryRegion>(context, CL_MEM_READ_WRITE, size, alignment);
     }
     // Try legacy buffer memory in case of failure
     if(region != nullptr && region->ptr() == nullptr)
     {
-        region = std::make_shared<CLBufferMemoryRegion>(context, CL_MEM_ALLOC_HOST_PTR | CL_MEM_READ_WRITE, size);
+        region = support::cpp14::make_unique<CLBufferMemoryRegion>(context, CL_MEM_ALLOC_HOST_PTR | CL_MEM_READ_WRITE, size);
     }
     return region;
 }
 } // namespace
 
 CLTensorAllocator::CLTensorAllocator(CLTensor *owner)
-    : _associated_memory_group(nullptr), _memory(), _owner(owner)
+    : _associated_memory_group(nullptr), _memory(), _mapping(nullptr), _owner(owner)
 {
 }
 
 uint8_t *CLTensorAllocator::data()
 {
-    ARM_COMPUTE_ERROR_ON(_memory.region() == nullptr);
-    return reinterpret_cast<uint8_t *>(_memory.region()->buffer());
+    return _mapping;
 }
 
 const cl::Buffer &CLTensorAllocator::cl_data() const
 {
-    ARM_COMPUTE_ERROR_ON(_memory.region() == nullptr);
-    return _memory.region()->cl_data();
+    return _memory.region() == nullptr ? _empty_buffer : _memory.cl_region()->cl_data();
 }
 
 void CLTensorAllocator::allocate()
 {
-    ARM_COMPUTE_ERROR_ON(_memory.region() == nullptr);
-
     if(_associated_memory_group == nullptr)
     {
-        if(_memory.region()->cl_data().get() != nullptr)
+        if(_memory.region() != nullptr && _memory.cl_region()->cl_data().get() != nullptr)
         {
             // Memory is already allocated. Reuse it if big enough, otherwise fire an assertion
-            ARM_COMPUTE_ERROR_ON_MSG(info().total_size() > _memory.region()->size(), "Reallocation of a bigger memory region is not allowed!");
+            ARM_COMPUTE_ERROR_ON_MSG(info().total_size() > _memory.region()->size(),
+                                     "Reallocation of a bigger memory region is not allowed!");
         }
         else
         {
             // Perform memory allocation
-            _memory = CLMemory(allocate_region(CLScheduler::get().context(), info().total_size(), 0));
+            _memory.set_owned_region(allocate_region(CLScheduler::get().context(), info().total_size(), 0));
         }
     }
     else
     {
-        _associated_memory_group->finalize_memory(_owner, _memory.region()->handle(), info().total_size());
-        _memory.region()->set_size(info().total_size());
+        _associated_memory_group->finalize_memory(_owner, _memory, info().total_size());
     }
     info().set_is_resizable(false);
 }
 
 void CLTensorAllocator::free()
 {
-    if(_associated_memory_group == nullptr)
-    {
-        _memory = CLMemory();
-        info().set_is_resizable(true);
-    }
+    _mapping = nullptr;
+    _memory.set_region(nullptr);
+    info().set_is_resizable(true);
 }
 
-arm_compute::Status CLTensorAllocator::import_memory(CLMemory memory)
+arm_compute::Status CLTensorAllocator::import_memory(cl::Buffer buffer)
 {
-    ARM_COMPUTE_ERROR_ON(_memory.region() == nullptr);
-    ARM_COMPUTE_RETURN_ERROR_ON(memory.region()->cl_data().get() == nullptr);
+    ARM_COMPUTE_RETURN_ERROR_ON(buffer.get() == nullptr);
+    ARM_COMPUTE_RETURN_ERROR_ON(buffer.getInfo<CL_MEM_SIZE>() == 0);
+    ARM_COMPUTE_RETURN_ERROR_ON(buffer.getInfo<CL_MEM_CONTEXT>().get() != CLScheduler::get().context().get());
     ARM_COMPUTE_RETURN_ERROR_ON(_associated_memory_group != nullptr);
-    _memory = memory;
+
+    _memory.set_owned_region(support::cpp14::make_unique<CLBufferMemoryRegion>(buffer));
     info().set_is_resizable(false);
 
     return Status{};
@@ -115,11 +116,10 @@ arm_compute::Status CLTensorAllocator::import_memory(CLMemory memory)
 
 void CLTensorAllocator::set_associated_memory_group(CLMemoryGroup *associated_memory_group)
 {
-    ARM_COMPUTE_ERROR_ON(_memory.region() == nullptr);
     ARM_COMPUTE_ERROR_ON(associated_memory_group == nullptr);
     ARM_COMPUTE_ERROR_ON(_associated_memory_group != nullptr);
-    ARM_COMPUTE_ERROR_ON(_memory.region()->cl_data().get() != nullptr);
-    _memory                  = CLMemory(std::make_shared<CLBufferMemoryRegion>(CLScheduler::get().context(), CL_MEM_ALLOC_HOST_PTR | CL_MEM_READ_WRITE, 0));
+    ARM_COMPUTE_ERROR_ON(_memory.region() != nullptr && _memory.cl_region()->cl_data().get() != nullptr);
+
     _associated_memory_group = associated_memory_group;
 }
 
@@ -136,16 +136,23 @@ void CLTensorAllocator::unlock()
 
 uint8_t *CLTensorAllocator::map(cl::CommandQueue &q, bool blocking)
 {
+    ARM_COMPUTE_ERROR_ON(_mapping != nullptr);
     ARM_COMPUTE_ERROR_ON(_memory.region() == nullptr);
     ARM_COMPUTE_ERROR_ON(_memory.region()->buffer() != nullptr);
-    _memory.region()->map(q, blocking);
-    return reinterpret_cast<uint8_t *>(_memory.region()->buffer());
+
+    _mapping = reinterpret_cast<uint8_t *>(_memory.cl_region()->map(q, blocking));
+    return _mapping;
 }
 
 void CLTensorAllocator::unmap(cl::CommandQueue &q, uint8_t *mapping)
 {
-    ARM_COMPUTE_UNUSED(mapping);
+    ARM_COMPUTE_ERROR_ON(_mapping == nullptr);
+    ARM_COMPUTE_ERROR_ON(_mapping != mapping);
     ARM_COMPUTE_ERROR_ON(_memory.region() == nullptr);
     ARM_COMPUTE_ERROR_ON(_memory.region()->buffer() == nullptr);
-    _memory.region()->unmap(q);
+    ARM_COMPUTE_UNUSED(mapping);
+
+    _memory.cl_region()->unmap(q);
+    _mapping = nullptr;
 }
+} // namespace arm_compute
diff --git a/src/runtime/GLES_COMPUTE/GCBufferAllocator.cpp b/src/runtime/GLES_COMPUTE/GCBufferAllocator.cpp
index cdd12c3ad5..70a1f4f8ff 100644
--- a/src/runtime/GLES_COMPUTE/GCBufferAllocator.cpp
+++ b/src/runtime/GLES_COMPUTE/GCBufferAllocator.cpp
@@ -22,10 +22,10 @@
  * SOFTWARE.
  */
 #include "arm_compute/runtime/GLES_COMPUTE/GCBufferAllocator.h"
-#include "arm_compute/runtime/GLES_COMPUTE/GCTensorAllocator.h"
 
 #include "arm_compute/core/Error.h"
 #include "arm_compute/core/GLES_COMPUTE/OpenGLES.h"
+#include "arm_compute/runtime/GLES_COMPUTE/GCMemoryRegion.h"
 
 #include <cstddef>
 
@@ -34,24 +34,26 @@ namespace arm_compute
 void *GCBufferAllocator::allocate(size_t size, size_t alignment)
 {
     ARM_COMPUTE_UNUSED(alignment);
-    auto *gl_buffer = new GLBufferWrapper();
-    ARM_COMPUTE_GL_CHECK(glBindBuffer(GL_SHADER_STORAGE_BUFFER, gl_buffer->_ssbo_name));
+
+    auto *gl_ssbo_name = new GLuint;
+    ARM_COMPUTE_GL_CHECK(glBindBuffer(GL_SHADER_STORAGE_BUFFER, *gl_ssbo_name));
     ARM_COMPUTE_GL_CHECK(glBufferData(GL_SHADER_STORAGE_BUFFER, static_cast<GLsizeiptr>(size), nullptr, GL_STATIC_DRAW));
     ARM_COMPUTE_GL_CHECK(glBindBuffer(GL_SHADER_STORAGE_BUFFER, 0));
 
-    return reinterpret_cast<void *>(gl_buffer);
+    return reinterpret_cast<void *>(gl_ssbo_name);
 }
 
 void GCBufferAllocator::free(void *ptr)
 {
     ARM_COMPUTE_ERROR_ON(ptr == nullptr);
-    auto *gl_buffer = reinterpret_cast<GLBufferWrapper *>(ptr);
-    delete gl_buffer;
+    auto *gl_ssbo_name = reinterpret_cast<GLuint *>(ptr);
+    ARM_COMPUTE_GL_CHECK(glDeleteBuffers(1, gl_ssbo_name));
+    delete gl_ssbo_name;
 }
 
 std::unique_ptr<IMemoryRegion> GCBufferAllocator::make_region(size_t size, size_t alignment)
 {
-    ARM_COMPUTE_UNUSED(size, alignment);
-    return nullptr;
+    ARM_COMPUTE_UNUSED(alignment);
+    return arm_compute::support::cpp14::make_unique<GCBufferMemoryRegion>(size);
 }
 } // namespace arm_compute
diff --git a/src/runtime/GLES_COMPUTE/GCMemory.cpp b/src/runtime/GLES_COMPUTE/GCMemory.cpp
new file mode 100644
index 0000000000..fed4a158a3
--- /dev/null
+++ b/src/runtime/GLES_COMPUTE/GCMemory.cpp
@@ -0,0 +1,81 @@
+/*
+ * 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.
+ */
+#include "arm_compute/runtime/GLES_COMPUTE/GCMemory.h"
+
+#include "arm_compute/core/utils/misc/Cast.h"
+#include "arm_compute/runtime/GLES_COMPUTE/GCMemoryRegion.h"
+
+namespace arm_compute
+{
+GCMemory::GCMemory()
+    : _region(nullptr), _region_owned(nullptr)
+{
+}
+
+GCMemory::GCMemory(std::shared_ptr<IGCMemoryRegion> memory)
+    : _region(nullptr), _region_owned(std::move(memory))
+{
+    _region_owned = memory;
+    _region       = _region_owned.get();
+}
+
+GCMemory::GCMemory(IGCMemoryRegion *memory)
+    : _region(memory), _region_owned(nullptr)
+{
+    _region = memory;
+}
+
+IGCMemoryRegion *GCMemory::gc_region()
+{
+    return _region;
+}
+
+IGCMemoryRegion *GCMemory::gc_region() const
+{
+    return _region;
+}
+
+IMemoryRegion *GCMemory::region()
+{
+    return _region;
+}
+
+IMemoryRegion *GCMemory::region() const
+{
+    return _region;
+}
+
+void GCMemory::set_region(IMemoryRegion *region)
+{
+    auto gc_region = utils::cast::polymorphic_downcast<IGCMemoryRegion *>(region);
+    _region_owned  = nullptr;
+    _region        = gc_region;
+}
+
+void GCMemory::set_owned_region(std::unique_ptr<IMemoryRegion> region)
+{
+    _region_owned = utils::cast::polymorphic_downcast_unique_ptr<IGCMemoryRegion>(std::move(region));
+    _region       = _region_owned.get();
+}
+} // namespace arm_compute
diff --git a/src/runtime/GLES_COMPUTE/GCMemoryRegion.cpp b/src/runtime/GLES_COMPUTE/GCMemoryRegion.cpp
new file mode 100644
index 0000000000..45fd6e8944
--- /dev/null
+++ b/src/runtime/GLES_COMPUTE/GCMemoryRegion.cpp
@@ -0,0 +1,96 @@
+/*
+ * 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.
+ */
+#include "arm_compute/runtime/GLES_COMPUTE/GCMemoryRegion.h"
+
+#include "arm_compute/core/Error.h"
+
+namespace arm_compute
+{
+IGCMemoryRegion::IGCMemoryRegion(size_t size)
+    : IMemoryRegion(size), _mapping(nullptr), _ssbo_name(0)
+{
+}
+
+const GLuint &IGCMemoryRegion::gc_ssbo_name() const
+{
+    return _ssbo_name;
+}
+
+void *IGCMemoryRegion::buffer()
+{
+    return _mapping;
+}
+
+void *IGCMemoryRegion::buffer() const
+{
+    return _mapping;
+}
+
+GCBufferMemoryRegion::GCBufferMemoryRegion(size_t size)
+    : IGCMemoryRegion(size)
+{
+    ARM_COMPUTE_GL_CHECK(glGenBuffers(1, &_ssbo_name));
+    ARM_COMPUTE_GL_CHECK(glBindBuffer(GL_SHADER_STORAGE_BUFFER, _ssbo_name));
+    ARM_COMPUTE_GL_CHECK(glBufferData(GL_SHADER_STORAGE_BUFFER, static_cast<GLsizeiptr>(size), nullptr, GL_STATIC_DRAW));
+    ARM_COMPUTE_GL_CHECK(glBindBuffer(GL_SHADER_STORAGE_BUFFER, 0));
+}
+
+GCBufferMemoryRegion::~GCBufferMemoryRegion()
+{
+    ARM_COMPUTE_GL_CHECK(glDeleteBuffers(1, &_ssbo_name));
+}
+
+void *GCBufferMemoryRegion::ptr()
+{
+    return nullptr;
+}
+
+void *GCBufferMemoryRegion::map(bool blocking)
+{
+    ARM_COMPUTE_ERROR_ON(_mapping != nullptr);
+    ARM_COMPUTE_UNUSED(blocking);
+
+    ARM_COMPUTE_GL_CHECK(glBindBuffer(GL_SHADER_STORAGE_BUFFER, _ssbo_name));
+    void *p  = ARM_COMPUTE_GL_CHECK(glMapBufferRange(GL_SHADER_STORAGE_BUFFER, 0, static_cast<GLsizeiptr>(size()), GL_MAP_READ_BIT | GL_MAP_WRITE_BIT));
+    _mapping = reinterpret_cast<uint8_t *>(p);
+
+    return _mapping;
+}
+
+void GCBufferMemoryRegion::unmap()
+{
+    ARM_COMPUTE_ERROR_ON(_mapping == nullptr);
+
+    ARM_COMPUTE_GL_CHECK(glBindBuffer(GL_SHADER_STORAGE_BUFFER, _ssbo_name));
+    ARM_COMPUTE_GL_CHECK(glUnmapBuffer(GL_SHADER_STORAGE_BUFFER));
+    ARM_COMPUTE_GL_CHECK(glBindBuffer(GL_SHADER_STORAGE_BUFFER, 0));
+    _mapping = nullptr;
+}
+
+std::unique_ptr<IMemoryRegion> GCBufferMemoryRegion::extract_subregion(size_t offset, size_t size)
+{
+    ARM_COMPUTE_UNUSED(offset, size);
+    return nullptr;
+}
+} // namespace arm_compute
\ No newline at end of file
diff --git a/src/runtime/GLES_COMPUTE/GCTensorAllocator.cpp b/src/runtime/GLES_COMPUTE/GCTensorAllocator.cpp
index abd2b483d3..a0dd540a7c 100644
--- a/src/runtime/GLES_COMPUTE/GCTensorAllocator.cpp
+++ b/src/runtime/GLES_COMPUTE/GCTensorAllocator.cpp
@@ -26,21 +26,17 @@
 
 #include "arm_compute/core/Error.h"
 #include "arm_compute/core/TensorInfo.h"
+#include "arm_compute/runtime/GLES_COMPUTE/GCMemoryRegion.h"
 #include "arm_compute/runtime/GLES_COMPUTE/GCScheduler.h"
 #include "support/ToolchainSupport.h"
 
 using namespace arm_compute;
 
 GCTensorAllocator::GCTensorAllocator(GCTensor *owner)
-    : _associated_memory_group(nullptr), _gl_buffer(), _mapping(nullptr), _owner(owner)
+    : _associated_memory_group(nullptr), _memory(), _mapping(nullptr), _owner(owner)
 {
 }
 
-GCTensorAllocator::~GCTensorAllocator()
-{
-    _gl_buffer = support::cpp14::make_unique<GLBufferWrapper>();
-}
-
 uint8_t *GCTensorAllocator::data()
 {
     return _mapping;
@@ -50,32 +46,28 @@ void GCTensorAllocator::allocate()
 {
     if(_associated_memory_group == nullptr)
     {
-        _gl_buffer = support::cpp14::make_unique<GLBufferWrapper>();
-        ARM_COMPUTE_GL_CHECK(glBindBuffer(GL_SHADER_STORAGE_BUFFER, _gl_buffer->_ssbo_name));
-        ARM_COMPUTE_GL_CHECK(glBufferData(GL_SHADER_STORAGE_BUFFER, static_cast<GLsizeiptr>(info().total_size()), nullptr, GL_STATIC_DRAW));
-        ARM_COMPUTE_GL_CHECK(glBindBuffer(GL_SHADER_STORAGE_BUFFER, 0));
+        _memory.set_owned_region(support::cpp14::make_unique<GCBufferMemoryRegion>(info().total_size()));
     }
     else
     {
-        _associated_memory_group->finalize_memory(_owner, reinterpret_cast<void **>(&_gl_buffer), info().total_size());
+        _associated_memory_group->finalize_memory(_owner, _memory, info().total_size());
     }
     info().set_is_resizable(false);
 }
 
 void GCTensorAllocator::free()
 {
-    if(_associated_memory_group == nullptr)
-    {
-        _gl_buffer.reset();
-        info().set_is_resizable(true);
-    }
+    _mapping = nullptr;
+    _memory.set_region(nullptr);
+    info().set_is_resizable(true);
 }
 
 void GCTensorAllocator::set_associated_memory_group(GCMemoryGroup *associated_memory_group)
 {
     ARM_COMPUTE_ERROR_ON(associated_memory_group == nullptr);
     ARM_COMPUTE_ERROR_ON(_associated_memory_group != nullptr);
-    ARM_COMPUTE_ERROR_ON(_gl_buffer.get() != nullptr);
+    ARM_COMPUTE_ERROR_ON(_memory.region() != nullptr && _memory.gc_region()->gc_ssbo_name() != 0);
+
     _associated_memory_group = associated_memory_group;
 }
 
@@ -91,27 +83,23 @@ void GCTensorAllocator::unlock()
 
 GLuint GCTensorAllocator::get_gl_ssbo_name() const
 {
-    return _gl_buffer->_ssbo_name;
+    return (_memory.region() == nullptr) ? static_cast<GLuint>(0) : _memory.gc_region()->gc_ssbo_name();
 }
 
 uint8_t *GCTensorAllocator::map(bool blocking)
 {
     ARM_COMPUTE_ERROR_ON(_mapping != nullptr);
-    ARM_COMPUTE_UNUSED(blocking);
-
-    ARM_COMPUTE_GL_CHECK(glBindBuffer(GL_SHADER_STORAGE_BUFFER, _gl_buffer->_ssbo_name));
-    void *p  = ARM_COMPUTE_GL_CHECK(glMapBufferRange(GL_SHADER_STORAGE_BUFFER, 0, static_cast<GLsizeiptr>(info().total_size()), GL_MAP_READ_BIT | GL_MAP_WRITE_BIT));
-    _mapping = reinterpret_cast<uint8_t *>(p);
+    ARM_COMPUTE_ERROR_ON(_memory.region() == nullptr);
 
+    _mapping = reinterpret_cast<uint8_t *>(_memory.gc_region()->map(blocking));
     return _mapping;
 }
 
 void GCTensorAllocator::unmap()
 {
     ARM_COMPUTE_ERROR_ON(_mapping == nullptr);
+    ARM_COMPUTE_ERROR_ON(_memory.region() == nullptr);
 
-    ARM_COMPUTE_GL_CHECK(glBindBuffer(GL_SHADER_STORAGE_BUFFER, _gl_buffer->_ssbo_name));
-    ARM_COMPUTE_GL_CHECK(glUnmapBuffer(GL_SHADER_STORAGE_BUFFER));
-    ARM_COMPUTE_GL_CHECK(glBindBuffer(GL_SHADER_STORAGE_BUFFER, 0));
+    _memory.gc_region()->unmap();
     _mapping = nullptr;
 }
\ No newline at end of file
diff --git a/src/runtime/ISimpleLifetimeManager.cpp b/src/runtime/ISimpleLifetimeManager.cpp
index faaff8a63e..7d928d6a7a 100644
--- a/src/runtime/ISimpleLifetimeManager.cpp
+++ b/src/runtime/ISimpleLifetimeManager.cpp
@@ -25,6 +25,7 @@
 
 #include "arm_compute/core/Error.h"
 #include "arm_compute/runtime/IAllocator.h"
+#include "arm_compute/runtime/IMemory.h"
 #include "arm_compute/runtime/IMemoryGroup.h"
 #include "arm_compute/runtime/IMemoryPool.h"
 #include "support/ToolchainSupport.h"
@@ -70,7 +71,7 @@ void ISimpleLifetimeManager::start_lifetime(void *obj)
     _active_elements.insert(std::make_pair(obj, obj));
 }
 
-void ISimpleLifetimeManager::end_lifetime(void *obj, void **handle, size_t size)
+void ISimpleLifetimeManager::end_lifetime(void *obj, IMemory &obj_memory, size_t size)
 {
     ARM_COMPUTE_ERROR_ON(obj == nullptr);
 
@@ -80,7 +81,7 @@ void ISimpleLifetimeManager::end_lifetime(void *obj, void **handle, size_t size)
 
     // Update object fields and mark object as complete
     Element &el = active_object_it->second;
-    el.handle   = handle;
+    el.handle   = &obj_memory;
     el.size     = size;
     el.status   = true;
 
diff --git a/src/runtime/Memory.cpp b/src/runtime/Memory.cpp
index 15bbb17675..d116624679 100644
--- a/src/runtime/Memory.cpp
+++ b/src/runtime/Memory.cpp
@@ -30,17 +30,13 @@ namespace arm_compute
 Memory::Memory()
     : _region(nullptr), _region_owned(nullptr)
 {
-    create_empty_region();
 }
 
 Memory::Memory(std::shared_ptr<IMemoryRegion> memory)
     : _region(nullptr), _region_owned(std::move(memory))
 {
-    if(_region_owned == nullptr)
-    {
-        create_empty_region();
-    }
-    _region = _region_owned.get();
+    _region_owned = memory;
+    _region       = _region_owned.get();
 }
 
 Memory::Memory(IMemoryRegion *memory)
@@ -59,9 +55,15 @@ IMemoryRegion *Memory::region() const
     return _region;
 }
 
-void Memory::create_empty_region()
+void Memory::set_region(IMemoryRegion *region)
+{
+    _region_owned = nullptr;
+    _region       = region;
+}
+
+void Memory::set_owned_region(std::unique_ptr<IMemoryRegion> region)
 {
-    _region_owned = std::make_shared<MemoryRegion>(0);
+    _region_owned = std::move(region);
     _region       = _region_owned.get();
 }
 } // namespace arm_compute
diff --git a/src/runtime/OffsetMemoryPool.cpp b/src/runtime/OffsetMemoryPool.cpp
index 96f54f890f..36eaf0ba1a 100644
--- a/src/runtime/OffsetMemoryPool.cpp
+++ b/src/runtime/OffsetMemoryPool.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017 ARM Limited.
+ * Copyright (c) 2017-2018 ARM Limited.
  *
  * SPDX-License-Identifier: MIT
  *
@@ -28,6 +28,7 @@
 #include "arm_compute/core/Error.h"
 #include "arm_compute/runtime/IAllocator.h"
 #include "arm_compute/runtime/IMemoryPool.h"
+#include "arm_compute/runtime/MemoryRegion.h"
 #include "arm_compute/runtime/Types.h"
 #include "support/ToolchainSupport.h"
 
@@ -37,14 +38,7 @@ OffsetMemoryPool::OffsetMemoryPool(IAllocator *allocator, size_t blob_size)
     : _allocator(allocator), _blob(), _blob_size(blob_size)
 {
     ARM_COMPUTE_ERROR_ON(!allocator);
-    _blob = _allocator->allocate(_blob_size, 0);
-}
-
-OffsetMemoryPool::~OffsetMemoryPool()
-{
-    ARM_COMPUTE_ERROR_ON(!_allocator);
-    _allocator->free(_blob);
-    _blob = nullptr;
+    _blob = _allocator->make_region(blob_size, 0);
 }
 
 void OffsetMemoryPool::acquire(MemoryMappings &handles)
@@ -55,7 +49,7 @@ void OffsetMemoryPool::acquire(MemoryMappings &handles)
     for(auto &handle : handles)
     {
         ARM_COMPUTE_ERROR_ON(handle.first == nullptr);
-        *handle.first = reinterpret_cast<uint8_t *>(_blob) + handle.second;
+        handle.first->set_owned_region(_blob->extract_subregion(handle.second, _blob_size - handle.second));
     }
 }
 
@@ -64,7 +58,7 @@ void OffsetMemoryPool::release(MemoryMappings &handles)
     for(auto &handle : handles)
     {
         ARM_COMPUTE_ERROR_ON(handle.first == nullptr);
-        *handle.first = nullptr;
+        handle.first->set_region(nullptr);
     }
 }
 
diff --git a/src/runtime/TensorAllocator.cpp b/src/runtime/TensorAllocator.cpp
index c84a2719d8..5fa51d7140 100644
--- a/src/runtime/TensorAllocator.cpp
+++ b/src/runtime/TensorAllocator.cpp
@@ -127,39 +127,35 @@ void TensorAllocator::init(const TensorAllocator &allocator, const Coordinates &
 
 uint8_t *TensorAllocator::data() const
 {
-    ARM_COMPUTE_ERROR_ON(_memory.region() == nullptr);
-    return reinterpret_cast<uint8_t *>(_memory.region()->buffer());
+    return (_memory.region() == nullptr) ? nullptr : reinterpret_cast<uint8_t *>(_memory.region()->buffer());
 }
 
 void TensorAllocator::allocate()
 {
-    ARM_COMPUTE_ERROR_ON(_memory.region() == nullptr);
-    ARM_COMPUTE_ERROR_ON(_memory.region()->buffer() != nullptr);
-
     if(_associated_memory_group == nullptr)
     {
-        _memory = Memory(std::make_shared<MemoryRegion>(info().total_size(), alignment()));
+        _memory.set_owned_region(support::cpp14::make_unique<MemoryRegion>(info().total_size(), alignment()));
     }
     else
     {
-        _associated_memory_group->finalize_memory(_owner, reinterpret_cast<void **>(_memory.region()->handle()), info().total_size());
-        _memory.region()->set_size(info().total_size());
+        _associated_memory_group->finalize_memory(_owner, _memory, info().total_size());
     }
     info().set_is_resizable(false);
 }
 
 void TensorAllocator::free()
 {
-    _memory = Memory();
+    _memory.set_region(nullptr);
     info().set_is_resizable(true);
 }
 
-arm_compute::Status TensorAllocator::import_memory(Memory memory)
+arm_compute::Status TensorAllocator::import_memory(void *memory, size_t size)
 {
-    ARM_COMPUTE_ERROR_ON(_memory.region() == nullptr);
-    ARM_COMPUTE_RETURN_ERROR_ON(memory.region()->buffer() == nullptr);
+    ARM_COMPUTE_RETURN_ERROR_ON(memory == nullptr);
+    ARM_COMPUTE_RETURN_ERROR_ON(size == 0);
     ARM_COMPUTE_RETURN_ERROR_ON(_associated_memory_group != nullptr);
-    _memory = memory;
+
+    _memory.set_owned_region(support::cpp14::make_unique<MemoryRegion>(memory, info().total_size()));
     info().set_is_resizable(false);
 
     return Status{};
@@ -167,10 +163,10 @@ arm_compute::Status TensorAllocator::import_memory(Memory memory)
 
 void TensorAllocator::set_associated_memory_group(MemoryGroup *associated_memory_group)
 {
-    ARM_COMPUTE_ERROR_ON(_memory.region() == nullptr);
     ARM_COMPUTE_ERROR_ON(associated_memory_group == nullptr);
     ARM_COMPUTE_ERROR_ON(_associated_memory_group != nullptr);
-    ARM_COMPUTE_ERROR_ON(_memory.region()->buffer() != nullptr);
+    ARM_COMPUTE_ERROR_ON(_memory.region() != nullptr && _memory.region()->buffer() != nullptr);
+
     _associated_memory_group = associated_memory_group;
 }