[llvm] X86: Add prefetch insertion based on Propeller profile (PR #166324)

[Simon Pilgrim via llvm-commits]

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@@ -50,21 +61,44 @@ struct FunctionPathAndClusterInfo {
   // the edge a -> b (a is not cloned). The index of the path in this vector
   // determines the `UniqueBBID::CloneID` of the cloned blocks in that path.
   SmallVector<SmallVector<unsigned>> ClonePaths;
+  SmallVector<PrefetchHint> PrefetchHints;
+  DenseSet<BBPosition> PrefetchTargets;
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RKSimon wrote:

Missing descriptions

https://github.com/llvm/llvm-project/pull/166324