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

[via llvm-commits]

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

Update test checks is a very neat tool I was not familiar with, so thank you for the pointer on that!

One issue I am seeing with combining the two tests into a single file is that it merges the final profile metadata (as they match). Is there a flag to prevent metadata merging? If not, is it an acceptable side effect that changes in folding behavior for the first test may cause the test to fail (because it would at least indicate an item that requires attention)?

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