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

[via llvm-commits]

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@@ -10203,8 +10092,9 @@ bool LoopVectorizePass::processLoop(Loop *L) {
           Value *ResumeV = nullptr;
           // TODO: Move setting of resume values to prepareToExecute.
           if (auto *ReductionPhi = dyn_cast<VPReductionPHIRecipe>(&R)) {
-            ResumeV = MainILV.getReductionResumeValue(
-                ReductionPhi->getRecurrenceDescriptor());
+            ResumeV = ReductionResumeValues
+                          .find(&ReductionPhi->getRecurrenceDescriptor())
+                          ->second;
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ayalz wrote:

```suggestion
            ResumeV = ReductionResumeValues[&ReductionPhi->getRecurrenceDescriptor()];
```
?

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