[llvm] [LoopVectorizer] Prune VFs based on plan register pressure (PR #132190)

[Sam Tebbs via llvm-commits]

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@@ -4532,7 +4515,16 @@ static bool hasReplicatorRegion(VPlan &Plan) {
                 [](auto *VPRB) { return VPRB->isReplicator(); });
 }
 
+/// Estimate the register usage for \p Plan and vectorization factors in \p VFs
+/// by calculating the highest number of values that are live at a single
+/// location as a rough estimate. Returns the register usage for each VF in \p
+/// VFs.
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SamTebbs33 wrote:

Done.

https://github.com/llvm/llvm-project/pull/132190