[llvm] [NFC][VPlan] Rename VPEVLBasedIVPHIRecipe to VPCurrentIterationPHIRecipe (PR #177114)

[Florian Hahn via llvm-commits]

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@@ -3264,9 +3264,10 @@ void VPlanTransforms::addExplicitVectorLength(
   auto *CanIVTy = LoopRegion->getCanonicalIVType();
   VPValue *StartV = CanonicalIVPHI->getStartValue();
 
-  // Create the ExplicitVectorLengthPhi recipe in the main loop.
-  auto *EVLPhi = new VPEVLBasedIVPHIRecipe(StartV, DebugLoc::getUnknown());
-  EVLPhi->insertAfter(CanonicalIVPHI);
+  // Create the CurrentIteration recipe in the main loop.
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fhahn wrote:

nit: while you are here, would be good to clarify main -> vector loop

```suggestion
  // Create the CurrentIteration recipe in the vector loop.
```



https://github.com/llvm/llvm-project/pull/177114