[llvm] [VPlan] Simplify branch on False in VPlan transform (NFC). (PR #140409)

[via llvm-commits]

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@@ -3737,6 +3738,15 @@ VPPhiAccessors::getIncomingBlock(unsigned Idx) const {
   return getAsRecipe()->getParent()->getCFGPredecessor(Idx);
 }
 
+inline void VPPhiAccessors::removeIncomingValue(VPBlockBase *VPB) const {
+  VPRecipeBase *R = const_cast<VPRecipeBase *>(getAsRecipe());
+  const VPBasicBlock *Parent = R->getParent();
+  assert(R->getNumOperands() == Parent->getNumPredecessors());
+  auto I = find(Parent->getPredecessors(), VPB);
----------------
ayalz wrote:

nit: may be clearer to use distance as in
```suggestion
  auto &Preds = R->getParent()->getPredecessors();
  assert(R->getNumOperands() == Preds.size() && "Number of phi operands must match number of predecessors");
  unsigned Position = std::distance(Preds.begin(), find(Preds, IncomingBlock));
```

https://github.com/llvm/llvm-project/pull/140409