Prominent Mesa developer Jason Ekstrand who formerly led Intel’s “ANV” Vulkan driver effort and being one of their open-source driver developers originally involved with the NIR intermediate representation work wrote a detailed and excellent blog post outlining its successes eight years running. While it still gets brought up into discussions from time to time (including quite recently stemming from a RISC-V graphics thread) why Mesa doesn’t use LLVM IR or SPIR-V directly as its intermediate representation, NIR continues as a striking success and used by all major Mesa drivers…
Source: Phoronix – NIR Continues Successfully Serving The Needs Of Mesa, Better Suited Than LLVM