[llvm] [IPO] NFC: avoid recalculating FunctionId hashes during ProfiledCallGraph construction (PR #109014)

[Nikita Popov via llvm-commits]

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@@ -58,6 +58,19 @@ struct ProfiledCallGraphNode {
   edges Edges;
 };
 
+struct PrehashedFunctionId {
+
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nikic wrote:

nit: Drop empty line.

https://github.com/llvm/llvm-project/pull/109014