[llvm] [ctx_prof] Profile flatterner (PR #104539)

[Aiden Grossman via llvm-commits]

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@@ -18,6 +20,9 @@ namespace llvm {
 
 class CtxProfAnalysis;
 
+using CtxProfFlatProfile =
+    DenseMap<GlobalValue::GUID, SmallVector<uint64_t, 16>>;
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boomanaiden154 wrote:

Was the value 16 here chosen arbitrarily or is there some data supporting it?

Probably not necessary to have much more than intuition here, but wouldn't hurt to have a data-backed value.

https://github.com/llvm/llvm-project/pull/104539