Oded Gabbay at Red Hat has provided a set of five patches for optimizing the Gallium3D-based LLVM-using LLVMpipe driver for POWER8 architecture. These POWER8 tweaks for PPC/PPC64LE implement VMX/VSX instruction support, similar to LLVMpipe's optimizations for Intel/AMD CPUs with SSE.
With the 600+ lines of new code for the LLVMpipe driver, games like Xonotic and OpenArena are running three to nearly seven percent faster on POWER8. More details via this patch series. It would be nice to see more performance optimizations for LLVMpipe and for this software-based implementation to have OpenGL 4 support in 2016.