[clang] [llvm] [InstCombine] Strip leading zero indices from GEP (PR #155415)

[Nikita Popov via llvm-commits]

nikic wrote:

@ritter-x2a Nice find! I guess this code is the culprit: https://github.com/llvm/llvm-project/blob/db8cad0c8d00a691d1365e9b2962a7f2f4ff0890/llvm/lib/Target/AMDGPU/AMDGPUPromoteAlloca.cpp#L404 It seems to treat ConstOffset as an unsigned number, while it is actually signed.

https://github.com/llvm/llvm-project/pull/155415