[llvm] [ctx_prof] Handle case when no root is in this Module. (PR #107463)

[Teresa Johnson via llvm-commits]

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@@ -0,0 +1,60 @@
+; REQUIRES: x86_64-linux
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teresajohnson wrote:

Add a comment about what case the test is checking

https://github.com/llvm/llvm-project/pull/107463