Intel Open-Sources Its OpenCL CPU-Based Runtime

As 718,996 lines of newly open-sourced code, Intel recently began opening up their previously proprietary CPU-based OpenCL run-time.

Pending for landing into Intel's LLVM repository downstream is this big merge request that amounts to 718,996 lines of new code spread across 2,750 files! This newly opened code is a CPU-based OpenCL implementation developed by the company.

The merge request was opened two weeks ago and contains their OpenCL CPU run-time, transform passes to support SYCL and OpenCL as well as related test cases.

This stems from a years-old request hoping for Intel to open-source their OpenCL CPU runtime. Back in 2020 there was indications from Intel engineers they wanted to open-source it and now indeed they have finally managed to do so.

For OpenCL CPU-based implementations there is most notably POCL as the "Portable Computing Language" implementation as well as the likes of Rusticl/Clover running atop LLVMpipe within Mesa. There has also been other OpenCL CPU-based execution efforts over the years while Intel's OpenCL CPU run-time will likely prove to be the most featureful as well as performant.

It's fantastic seeing Intel finally open-source their OpenCL CPU code and it will be interesting to see its adoption and open usage moving forward.