[llvm] [VPlan] Track VPValues instead of VPRecipes in calculateRegisterUsage. (PR #155301)

[Florian Hahn via llvm-commits]

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@@ -470,32 +471,32 @@ SmallVector<VPRegisterUsage, 8> llvm::calculateRegisterUsageForPlan(
         }
 
         // Overwrite previous end points.
-        EndPoint[DefR] = Idx2Recipe.size();
-        Ends.insert(DefR);
+        EndPoint[U] = Idx2Recipe.size();
+        Ends.insert(U);
       }
     }
     if (VPBB == LoopRegion->getExiting()) {
       // VPWidenIntOrFpInductionRecipes are used implicitly at the end of the
       // exiting block, where their increment will get materialized eventually.
       for (auto &R : LoopRegion->getEntryBasicBlock()->phis()) {
-        if (isa<VPWidenIntOrFpInductionRecipe>(&R)) {
-          EndPoint[&R] = Idx2Recipe.size();
-          Ends.insert(&R);
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fhahn wrote:

In some cases it will help, but in some cases it will make our live more difficult (e.g. VPExpressionRecipe).

https://github.com/llvm/llvm-project/pull/155301