[llvm] [InstCombine] Handle more scalable geps in EmitGEPOffset (PR #71699)

[David Green via llvm-commits]

davemgreen wrote:

It appears that the `& PtrSizeMask` can be removed without altering any of the lit tests or any of the programs I tried across AArch64/Arm. Let me know if you think I should re-add it.


https://github.com/llvm/llvm-project/pull/71699