[llvm] [VPlan] Peek through nested phi incoming values in computeBlendMasks (PR #203164)

[Luke Lau via llvm-commits]

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@@ -293,6 +297,17 @@ VPPredicator::computeBlendEdges(VPPhi *Phi) {
     for (EdgeTy Edge : OutEdges)
       Edges.erase(Edge);
 
+    // If the value is a phi postdominated by VPBB, then look through the inner
+    // incoming values instead of propagating the phi.
+    if (auto *Phi = dyn_cast<VPPhi>(Common))
+      if (Phi->hasOneUse() && VPPDT.dominates(VPBB, Phi->getParent())) {
+        for (auto [InV, InVPBB] : Phi->incoming_values_and_blocks()) {
+          AddEdge(InVPBB, Phi->getParent(), InV);
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lukel97 wrote:

Fixed in f391e26ecec4c638dc8b46938ce1811c490fb1fc, thanks

https://github.com/llvm/llvm-project/pull/203164