Opencl datahandling

Since the target_dh_refactoring was never merged, we decided to do the refactoring at smaller steps and recover the original OpenCL datahandling PR.

Refactoring to merge target and backend can be done later.

pystencils/boundaries/boundaryhandling.py

@@ -87,8 +87,26 @@ class BoundaryHandling:
         fi = flag_interface
         self.flag_interface = fi if fi is not None else FlagInterface(data_handling, name + "Flags")
 
-        gpu = self._target == 'gpu'
-        data_handling.add_custom_class(self._index_array_name, self.IndexFieldBlockData, cpu=True, gpu=gpu)
+        gpu = self._target in self._data_handling._GPU_LIKE_TARGETS
+        class_ = self.IndexFieldBlockData
+        if self._target == 'opencl':
+            def opencl_to_device(gpu_version, cpu_version):
+                from pyopencl import array
+                gpu_version = gpu_version.boundary_object_to_index_list
+                cpu_version = cpu_version.boundary_object_to_index_list
+                for obj, cpu_arr in cpu_version.items():
+                    if obj not in gpu_version or gpu_version[obj].shape != cpu_arr.shape:
+                        from pystencils.opencl.opencljit import get_global_cl_queue
+
+                        queue = self._data_handling._opencl_queue or get_global_cl_queue()
+                        gpu_version[obj] = array.to_device(queue, cpu_arr)
+                    else:
+                        gpu_version[obj].set(cpu_arr)
+
+            class_ = type('opencl_class', (self.IndexFieldBlockData,), {
+                'to_gpu': opencl_to_device
+            })
+        data_handling.add_custom_class(self._index_array_name, class_, cpu=True, gpu=gpu)
 
     @property
     def data_handling(self):
@@ -204,7 +222,7 @@ class BoundaryHandling:
         if self._dirty:
             self.prepare()
 
-        for b in self._data_handling.iterate(gpu=self._target == 'gpu'):
+        for b in self._data_handling.iterate(gpu=self._target in self._data_handling._GPU_LIKE_TARGETS):
             for b_obj, idx_arr in b[self._index_array_name].boundary_object_to_index_list.items():
                 kwargs[self._field_name] = b[self._field_name]
                 kwargs['indexField'] = idx_arr
@@ -219,7 +237,7 @@ class BoundaryHandling:
         if self._dirty:
             self.prepare()
 
-        for b in self._data_handling.iterate(gpu=self._target == 'gpu'):
+        for b in self._data_handling.iterate(gpu=self._target in self._data_handling._GPU_LIKE_TARGETS):
             for b_obj, idx_arr in b[self._index_array_name].boundary_object_to_index_list.items():
                 arguments = kwargs.copy()
                 arguments[self._field_name] = b[self._field_name]
@@ -302,7 +320,7 @@ class BoundaryHandling:
     def _boundary_data_initialization(self, boundary_obj, boundary_data_setter, **kwargs):
         if boundary_obj.additional_data_init_callback:
             boundary_obj.additional_data_init_callback(boundary_data_setter, **kwargs)
-        if self._target == 'gpu':
+        if self._target in self._data_handling._GPU_LIKE_TARGETS:
             self._data_handling.to_gpu(self._index_array_name)
 
     class BoundaryInfo(object):