[llvm] SimplifyCFG: Enable switch replacements in more cases (PR #156477)

[Jessica Del via llvm-commits]

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@@ -89,7 +89,7 @@ bb3:                                              ; preds = %bb1, %bb2
 
 define i1 @test2(i32 %c) {
 ; CHECK-LABEL: @test2(
-; CHECK-NEXT:    [[TMP2:%.*]] = tail call noundef i1 @test1(i32 [[TMP0:%.*]]) #[[ATTR0:[0-9]+]]
+; CHECK-NEXT:    [[TMP2:%.*]] = tail call i1 @test1(i32 [[TMP0:%.*]]) #[[ATTR0:[0-9]+]]
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OutOfCache wrote:

This change happens because we optimize the switch away much sooner and apparently it becomes more difficult to apply the `noundef` attribute to the function then.

https://github.com/llvm/llvm-project/pull/156477