[llvm] [SimplifyCFG] Don't use a mask for lookup tables generated from switches with an unreachable default case (PR #94468)

[Nikita Popov via llvm-commits]

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@@ -0,0 +1,534 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt < %s -passes=simplifycfg -switch-to-lookup=true -keep-loops=false -S | FileCheck %s
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nikic wrote:

I don't think `-keep-loops` is relevant here? We also don't need both RUN lines, they do the same thing.

https://github.com/llvm/llvm-project/pull/94468