[PATCH] Implement aarch64 neon instruction class SIMD Perm - Clang

[Tim Northover]

> Are you talking about the intrinsics without digit suffix like vuzp_s8? They
> looks like legacy for me. If yes, I think this is already covered. I have
> test like the followings,

Ah, I see what's happening. A dummy ARM intrinsic that gets expanded
to a proper shufflevector in CGBuiltins.cpp. That's fairly disgusting,
but obviously has precedent.

I may take a poke at it tomorrow if I get the chance. In the meantime,
I think this patch is OK for now.

Cheers.

Tim.