What is the NVIDIA Runtime Compiler?

The NVIDIA Runtime Compiler (nvrtc) is a runtime compilation library for CUDA C. It compiles CUDA C++ to PTX without requiring a separate launch of the NVIDIA CUDA Compiler Driver (nvcc) in another process. It is used by some libraries or frameworks to, for example, map generated C/C++ code to PTX code that can run on a GPU.

Note that this PTX is then further JIT-compiled from the PTX IR to the SASS assembly . This is done by the NVIDIA GPU drivers and is distinct from the compilation done by NVRTC. CUDA binaries that contain PTX , as required for forward compatibility, also pass through this compilation step.

NVRTC is closed source. You can find its documentation here .