[llvm] [CGP] Fix missing sign extension for base offset in optimizeMemoryInst (PR #161377)

[Yingwei Zheng via llvm-commits]

https://github.com/dtcxzyw approved this pull request.

Nice catch!
Should we also use sign extend here?
https://github.com/llvm/llvm-project/blob/4c2b1d495aa26fa80833fa1508736df984b6f55e/llvm/lib/CodeGen/CodeGenPrepare.cpp#L3197


https://github.com/llvm/llvm-project/pull/161377