[llvm] [SimplifyCFG] Delete the unnecessary range check for small mask operation (PR #65835)

[Nikita Popov via llvm-commits]

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@@ -6552,10 +6552,25 @@ static bool SwitchToLookupTable(SwitchInst *SI, IRBuilder<> &Builder,
     // Note: We call removeProdecessor later since we need to be able to get the
     // PHI value for the default case in case we're using a bit mask.
   } else {
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nikic wrote:

Can we adjust GeneratingCoveredLookupTable before the if instead, and reuse that code path?

https://github.com/llvm/llvm-project/pull/65835