[llvm] [InstCombine] Canonicalize gep scaling factor (PR #180216)

[Nikita Popov via llvm-commits]

nikic wrote:

Compile-time: https://llvm-compile-time-tracker.com/compare.php?from=edebc7544ee17e0f6ee56077307029fd92d460f2&to=d6e8e9aa33ce3d41aa5e6bcb09038e54c8733ad4&stat=instructions:u
Text size: https://llvm-compile-time-tracker.com/compare.php?from=edebc7544ee17e0f6ee56077307029fd92d460f2&to=d6e8e9aa33ce3d41aa5e6bcb09038e54c8733ad4&stat=size-text

https://github.com/llvm/llvm-project/pull/180216