[llvm] [AArch64] Fold tbl1 intrinsic into dup when broadcasting (PR #170872)

[via llvm-commits]

valadaptive wrote:

I added an InstCombine transform that converts tbl calls with static masks into shufflevector operations in https://github.com/llvm/llvm-project/pull/169748. Will this be necessary if that lands?

https://github.com/llvm/llvm-project/pull/170872