[llvm] [VPlan] Introduce generic variable-length step support (PR #177114)

[Luke Lau via llvm-commits]

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@@ -4606,9 +4607,9 @@ void VPActiveLaneMaskPHIRecipe::printRecipe(raw_ostream &O, const Twine &Indent,
 #endif
 
 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
-void VPEVLBasedIVPHIRecipe::printRecipe(raw_ostream &O, const Twine &Indent,
-                                        VPSlotTracker &SlotTracker) const {
-  O << Indent << "EXPLICIT-VECTOR-LENGTH-BASED-IV-PHI ";
+void VPCurrentIterationRecipe::printRecipe(raw_ostream &O, const Twine &Indent,
+                                           VPSlotTracker &SlotTracker) const {
+  O << Indent << "Current-Iteration-PHI ";
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lukel97 wrote:

Nit, use capitals to match the other recipes?
```suggestion
  O << Indent << "CURRENT-ITERATION-PHI ";
```

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