[llvm] 439c7ca - [VPlan] Simplify&clarify skipping VPValues in calculateRegisterUse (NFC)

[Florian Hahn via llvm-commits]

Author: Florian Hahn
Date: 2026-03-16T15:24:21Z
New Revision: 439c7ca9ad01d7bf3858f79b4c4b553faa998879

URL: https://github.com/llvm/llvm-project/commit/439c7ca9ad01d7bf3858f79b4c4b553faa998879
DIFF: https://github.com/llvm/llvm-project/commit/439c7ca9ad01d7bf3858f79b4c4b553faa998879.diff

LOG: [VPlan] Simplify&clarify skipping VPValues in calculateRegisterUse (NFC)

Split off as suggested in https://github.com/llvm/llvm-project/pull/156262/.

This refactors the code to clarify comments and code, in preparation for #156262.

Added: 
    

Modified: 
    llvm/lib/Transforms/Vectorize/VPlanAnalysis.cpp

Removed: 
    


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diff  --git a/llvm/lib/Transforms/Vectorize/VPlanAnalysis.cpp b/llvm/lib/Transforms/Vectorize/VPlanAnalysis.cpp
index 55f2a626c293a..5adb786475176 100644
--- a/llvm/lib/Transforms/Vectorize/VPlanAnalysis.cpp
+++ b/llvm/lib/Transforms/Vectorize/VPlanAnalysis.cpp
@@ -455,25 +455,21 @@ SmallVector<VPRegisterUsage, 8> llvm::calculateRegisterUsageForPlan(
 
       // Save the end location of each USE.
       for (VPValue *U : R.operands()) {
-        auto *DefR = U->getDefiningRecipe();
-
-        // Ignore non-recipe values such as arguments, constants, etc.
-        // FIXME: Might need some motivation why these values are ignored. If
-        // for example an argument is used inside the loop it will increase the
-        // register pressure (so shouldn't we add it to LoopInvariants).
-        auto *IRV = dyn_cast<VPIRValue>(U);
-        if (!DefR && (!IRV || !isa<Instruction>(IRV->getValue())))
-          continue;
-
-        // If this recipe is outside the loop then record it and continue.
-        if (!DefR) {
+        if (auto *DefR = U->getDefiningRecipe()) {
+          // Overwrite previous end points.
+          EndPoint[U] = Idx2Recipe.size();
+          Ends.insert(U);
+        } else if (auto *IRV = dyn_cast<VPIRValue>(U)) {
+          // Ignore non-recipe values such as arguments, constants, etc.
+          // FIXME: Might need some motivation why these values are ignored. If
+          // for example an argument is used inside the loop it will increase
+          // the register pressure (so shouldn't we add it to LoopInvariants).
+          if (!isa<Instruction>(IRV->getValue()))
+            continue;
+          // This recipe is outside the loop, record it and continue.
           LoopInvariants.insert(U);
-          continue;
         }
-
-        // Overwrite previous end points.
-        EndPoint[U] = Idx2Recipe.size();
-        Ends.insert(U);
+        // Other types of VPValue are currently not tracked.
       }
     }
     if (VPBB == LoopRegion->getExiting()) {