[llvm] [SimplifyCFG][PGO] Add missing overflow check to ConstantFoldTerminator (PR #178964)

[Mitchel Dickerson via llvm-commits]

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@@ -0,0 +1,23 @@
+; RUN: opt < %s -passes=simplifycfg -S | FileCheck %s
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mauve-stinger wrote:

I will try different weights that still trigger the same behavior and see if I can get a case that avoids the optimizer. If that doesn't work, then I will change the `switch` case like you suggested.

https://github.com/llvm/llvm-project/pull/178964