[llvm] [VPlan] Introduce ComputeReductionResult VPInstruction opcode. (PR #70253)

[Florian Hahn via llvm-commits]

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@@ -3434,8 +3419,15 @@ void InnerLoopVectorizer::fixVectorizedLoop(VPTransformState &State,
   // At this point every instruction in the original loop is widened to a
   // vector form. Now we need to fix the recurrences in the loop. These PHI
   // nodes are currently empty because we did not want to introduce cycles.
-  // This is the second stage of vectorizing recurrences.
-  fixCrossIterationPHIs(State);
+  // This is the second stage of vectorizing recurrences. Note that fixing
+  // reduction phis are already modeled in VPlan.
+  // TODO: Also model fixing fixed-order recurrence phis in VPlan.
+  VPRegionBlock *VectorRegion = State.Plan->getVectorLoopRegion();
+  VPBasicBlock *Header = VectorRegion->getEntryBasicBlock();
+  for (VPRecipeBase &R : Header->phis()) {
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fhahn wrote:

Done, thanks!

https://github.com/llvm/llvm-project/pull/70253