CLT - An OpenCL Toolkit

CLT is a toolkit that makes managing large-scale OpenCL codebases easier.

Features

• Context creation:
  • Platform and device selection by name
  • GL-CL interop setup
  • CPU debugging setup (Intel processors)
• Custom kernel class with several convenience features
  • Kernels implemented as classes
    • All setup exists in one place
    • No initialization step is accidentally forgotten
    • Kernel source can be inlined in class
  • Kernel arguments set by name (not by idx)
    • Adding new arguments does not invalidate old argument indices
  • Supports conservative recompilation when preprocessor definitions change
    • Can turn off branches with #ifdefs to keep register pressure low
• Kernel binaries cached for a massive speedup
  • Special care is taken to support #includes on all platforms (default NVIDIA kernel cache does not)

Usage

1. Add CLT as a git submodule, include clt.hpp
2. Call clt::initialize() (or initialize OpenCL manually)
3. Create a kernel class that extends clt::Kernel:

   class MyKernel : public clt::Kernel {
   public:
       MyKernel (void) : Kernel("kernel.cl", "mainFunc") {};
       std::string getAdditionalBuildOptions() override {
           return " -DCONFIG_POWER=" + std::to_string(global_variable);
       }
       void setArgs() override {
           setArg("input", inputArr);
           setArg("output", outputArr);
       }
       CLT_KERNEL_IMPL(
       kernel void mainFunc(global int* input, global int* output) {
           // Optional inline source, can also be read from file
           uint gid = get_global_id(0);
           output[gid] = pow(input[gid], CONFIG_POWER);
       })
   };

4. Call mykernel.build()
5. Call mykernel.rebuild() whenever configuration changes (only recompiled if needed)

See example/ for a usage example.
Check out Fluctus to see CLT in use in a large-scale OpenCL codebase.

Configuration

CLT can be configured to use cl.hpp instead of cl2.hpp (for compatibility with older projects). This is done by adding set(CLT_USE_LEGACY_HEADER ON CACHE BOOL " " FORCE) and add_definitions(-DCLT_CL_LEGACY_HEADER) to CMakeLists.txt

License

See the LICENSE file for license rights and limitations (MIT).