[llvm] [LV] Reduce register usage for scaled reductions (PR #133090)

[Sander de Smalen via llvm-commits]

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@@ -71,6 +71,11 @@ raw_ostream &llvm::operator<<(raw_ostream &OS, const VPValue &V) {
   V.print(OS, SlotTracker);
   return OS;
 }
+raw_ostream &llvm::operator<<(raw_ostream &OS, const VPRecipeBase &R) {
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sdesmalen-arm wrote:

Instead of adding this operator, you can instead replace the one above `operator<<(raw_ostem &OS, const VPValue &V)`. If this operator supports `VPRecipeBase` then that also removes the need for a cast in SLPVectorizer.cpp and the one you added in VPlanTest.cpp.

https://github.com/llvm/llvm-project/pull/133090