[llvm] [SCEVExpander] Clear flags when reusing GEP (PR #109293)

[Nikita Popov via llvm-commits]

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@@ -9,19 +9,21 @@ target triple = "wasm32-unknown-unknown"
 define void @shl_loop(ptr %a, i8 %shift, i32 %count) {
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nikic wrote:

A bit unfortunate that this regresses, but I think we'll recover this in the future (after https://github.com/llvm/llvm-project/pull/102133 + inference for gep nuw in instcombine, at which point we should be able to preserve the nuw flag here, which is all wasm cares about).

https://github.com/llvm/llvm-project/pull/109293