LunarGLASS Adds Experimental SPIR-V Front-End

LunarG, the consulting company around open-source Linux graphics drivers, is one of the organizations involved heavily with the new Vulkan graphics API and SPIR-V intermediate representation. Thanks to their involvement, they already have out an initial SPIR-V front-end to their open-source LunarGLASS Mesa project.

LunarGLASS is "LunarG's LLVM adaptation to shader compiler stacks" and with this new SPIR-V front-end they can convert Vulkan's new IR into their LLVM-based Top IR. This new front-end is considered very experimental and provides approximately GLSL 3.xx functionality. The Top IR is platform-independent which is then translated to LunarGLASS' bottom-level IR that is dynamically changed for the particular graphics architecture.

The LunarGLASS commit adding their initial SPIR-V front-end was made to their Google Code repository.

This front-end is one step towards converting SPIR-V into LLVM IR as LunarG's IR is based upon it, but the Khronos Group is said to also be coming out with their own SPIR-V to LLVM IR converter for use by others. For most open-source Linux graphics users this LunarGLASS addition won't mean much since you won't already have any SPIR-V IR at this time for the front-end to consume and this forked version of Mesa isn't widely used besides LunarG's demo purposes. LunarGLASS remains focused on reducing the development burden for advanced compiler stacks and increasing the level opf optimizations for real-world workloads.