[clang] [clang] Emit nuw GEPs for array subscript expressions (PR #103088)

[Eli Friedman via cfe-commits]

efriedma-quic wrote:

> adding nuw is also valid for signed indices here

I don't understand how you think this would work; a-1 and a+-1 are required to produce the same result.

https://github.com/llvm/llvm-project/pull/103088