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

[via llvm-commits]

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@@ -0,0 +1,1506 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals
+; RUN: opt < %s -passes=simplifycfg -switch-to-lookup=true -keep-loops=false -S -mtriple=x86_64-unknown-linux-gnu | FileCheck %s
+; RUN: opt < %s -passes='simplifycfg<no-keep-loops;switch-to-lookup>' -S -mtriple=x86_64-unknown-linux-gnu | FileCheck %s
+target datalayout = "e-p:64:64:64-i1:8:8-i32:8:8-i16:16:16-i32:32:32-i32:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
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DaMatrix wrote:

Very good point, I didn't even think of that! I've done that in the latest revision.

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