Dataflow SubFunction OpenCL (OpenCL Kernel)

This is simple example of vector addition to demonstrate how OpenCL Dataflow allows user to run multiple sub functions together to achieve higher throughput.

KEY CONCEPTS: SubFunction Level Parallelism

KEYWORDS: xcl_dataflow, xclDataflowFifoDepth

This example demonstrates how xcl_dataflow attribute can be used to implement task level parallelism for subfunctions inside a function.

adder kernel uses a function run_subfunc which has 3 subfunctions read_input, compute_add and write_result. xcl_dataflow is used here to parallelize these subfunctions inside run_subfunc.

__attribute__ ((xcl_dataflow))
void run_subfunc(__global int *in, __global int *out, int inc, int size)
{
    int buffer_in[BUFFER_SIZE];
    int buffer_out[BUFFER_SIZE];

    read_input(in,buffer_in,size);
    compute_add(buffer_in,buffer_out,inc,size);
    write_result(out,buffer_out,size);
}

EXCLUDED PLATFORMS

Platforms containing following strings in their names are not supported for this example :

nodma

DESIGN FILES

Application code is located in the src directory. Accelerator binary files will be compiled to the xclbin directory. The xclbin directory is required by the Makefile and its contents will be filled during compilation. A listing of all the files in this example is shown below

src/adder.cl
src/host.cpp

Access these files in the github repo by clicking here.

COMMAND LINE ARGUMENTS

Once the environment has been configured, the application can be executed by

./cl_dataflow_subfunc <adder XCLBIN>