[llvm] [FuncSpec] Update function specialization to handle phi-chains (PR #72903)

[Alexandros Lamprineas via llvm-commits]

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@@ -0,0 +1,54 @@
+; RUN: opt -passes="ipsccp<func-spec>" -funcspec-min-function-size=20 -funcspec-for-literal-constant -S < %s
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labrinea wrote:

Have you checked `-funcspec-min-function-size=20` is the "size" of bar? The function seems smaller than the previous example just above. I would expect a lower value would allow specialization. If you have checked that the test is passing disregard this comment.

https://github.com/llvm/llvm-project/pull/72903