[llvm] [VPlan] Support VPWidenCastRecipe in isSingleScalar. (PR #143552)

[Alexey Bataev via llvm-commits]

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@@ -1194,13 +1195,19 @@ static void narrowToSingleScalarRecipes(VPlan &Plan) {
         continue;
 
       auto *RepOrWidenR = cast<VPSingleDefRecipe>(&R);
+      Instruction *UI = RepOrWidenR->getUnderlyingInstr();
+      if (!UI)
+        continue;
+
       // Skip recipes that aren't single scalars or don't have only their
       // scalar results used. In the latter case, we would introduce extra
       // broadcasts.
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alexey-bataev wrote:

Update comment?

https://github.com/llvm/llvm-project/pull/143552