Elena Demikhovsky of Intel landed this weekend the Skylake x86 target in LLVM that exposes all of the various CPU instruction set extensions supported by these latest-generation processors. There is also the Skylake server processor class for those with AVX-512 support.
Some new features like SMAP, IFMA, and PREFETCHWT1 are also now being exposed properly for the correct generations of Intel hardware. The code today also adjusts for next year's Cannonlake processors.
More details via this commit.