[llvm] [VPlan] Improve cast code in VPlanRecipes (NFC) (PR #141240)

[Ramkumar Ramachandra via llvm-commits]

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@@ -85,8 +85,8 @@ bool VPRecipeBase::mayWriteToMemory() const {
   case VPWidenPHISC:
   case VPWidenSC:
   case VPWidenSelectSC: {
-    const Instruction *I =
-        dyn_cast_or_null<Instruction>(getVPSingleValue()->getUnderlyingValue());
+    const Instruction *I = dyn_cast_if_present<Instruction>(
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artagnon wrote:

Yes, they're equivalent, but there's a comment in the file saying that the latter has been deprecated, but I'm not sure if we're making an effort to get rid of it.

https://github.com/llvm/llvm-project/pull/141240