func (this *buffer) CreateSubBuffer(flags cl.CL_mem_flags,
buffer_create_type cl.CL_buffer_create_type,
buffer_create_info unsafe.Pointer) (Buffer, error) {
var errCode cl.CL_int
if memory_id := cl.CLCreateSubBuffer(this.memory_id,
flags,
buffer_create_type,
buffer_create_info,
&errCode); errCode != cl.CL_SUCCESS {
return nil, fmt.Errorf("CreateSubBuffer failure with errcode_ret %d: %s", errCode, cl.ERROR_CODES_STRINGS[-errCode])
} else {
return &buffer{memory{memory_id}}, nil
}
}
func main() {
/* Host/device data structures */
var device []cl.CL_device_id
var context cl.CL_context
var err cl.CL_int
/* Data and buffers */
var main_data [100]float32
var main_buffer, sub_buffer cl.CL_mem
var main_buffer_mem, sub_buffer_mem interface{}
var main_buffer_size, sub_buffer_size interface{}
var buffer_size cl.CL_size_t
var buffer_mem cl.CL_ulong
var region cl.CL_buffer_region
/* Create device and context */
device = utils.Create_device()
context = cl.CLCreateContext(nil, 1, device[:], nil, nil, &err)
if err < 0 {
println("Couldn't create a context")
return
}
/* Create a buffer to hold 100 floating-point values */
main_buffer = cl.CLCreateBuffer(context, cl.CL_MEM_READ_ONLY|
cl.CL_MEM_COPY_HOST_PTR, cl.CL_size_t(unsafe.Sizeof(main_data)), unsafe.Pointer(&main_data[0]), &err)
if err < 0 {
println("Couldn't create a buffer")
return
}
/* Create a sub-buffer containing values 30-49 */
region.Origin = 30 * cl.CL_size_t(unsafe.Sizeof(main_data[0]))
region.Size = 20 * cl.CL_size_t(unsafe.Sizeof(main_data[0]))
fmt.Printf("origin=%d, size=%d\n", region.Origin, region.Size)
sub_buffer = cl.CLCreateSubBuffer(main_buffer, cl.CL_MEM_READ_ONLY|
cl.CL_MEM_COPY_HOST_PTR, cl.CL_BUFFER_CREATE_TYPE_REGION, unsafe.Pointer(®ion), &err)
if err < 0 {
fmt.Printf("Couldn't create a sub-buffer, errcode=%d\n", err)
return
}
/* Obtain size information about the buffers */
cl.CLGetMemObjectInfo(main_buffer, cl.CL_MEM_SIZE,
cl.CL_size_t(unsafe.Sizeof(buffer_size)), &main_buffer_size, nil)
cl.CLGetMemObjectInfo(sub_buffer, cl.CL_MEM_SIZE,
cl.CL_size_t(unsafe.Sizeof(buffer_size)), &sub_buffer_size, nil)
fmt.Printf("Main buffer size: %v\n", main_buffer_size.(cl.CL_size_t))
fmt.Printf("Sub-buffer size: %v\n", sub_buffer_size.(cl.CL_size_t))
/* Obtain the host pointers */
cl.CLGetMemObjectInfo(main_buffer, cl.CL_MEM_HOST_PTR, cl.CL_size_t(unsafe.Sizeof(buffer_mem)),
&main_buffer_mem, nil)
cl.CLGetMemObjectInfo(sub_buffer, cl.CL_MEM_HOST_PTR, cl.CL_size_t(unsafe.Sizeof(buffer_mem)),
&sub_buffer_mem, nil)
fmt.Printf("Main buffer memory address: %v\n", main_buffer_mem.(cl.CL_ulong))
fmt.Printf("Sub-buffer memory address: %v\n", sub_buffer_mem.(cl.CL_ulong))
/* Print the address of the main data */
fmt.Printf("Main array address: %v\n", main_data)
/* Deallocate resources */
cl.CLReleaseMemObject(main_buffer)
cl.CLReleaseMemObject(sub_buffer)
cl.CLReleaseContext(context)
}