[llvm] [SCEV] Simplify getElementSz using getLoadStore-helpers (NFC) (PR #222908)

[Florian Hahn via llvm-commits]

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@@ -14026,20 +14026,12 @@ bool ScalarEvolution::containsErasedValue(const SCEV *S) const {
 
 /// Return the size of an element read or written by Inst.
 const SCEV *ScalarEvolution::getElementSize(Instruction *Inst) {
-  Type *Ty;
-  Type *PtrTy;
-  if (StoreInst *Store = dyn_cast<StoreInst>(Inst)) {
-    Ty = Store->getValueOperand()->getType();
-    PtrTy = Store->getPointerOperandType();
-  } else if (LoadInst *Load = dyn_cast<LoadInst>(Inst)) {
-    Ty = Load->getType();
-    PtrTy = Load->getPointerOperandType();
-  } else {
+  if (!isa<LoadInst, StoreInst>(Inst))
     return nullptr;
-  }
-
-  Type *ETy = getEffectiveSCEVType(PtrTy);
-  return getSizeOfExpr(ETy, Ty);
+  Type *Ty = getLoadStoreType(Inst);
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fhahn wrote:

nit: perhaps slightly clearer
```suggestion
  Type *AccessTy = getLoadStoreType(Inst);
```

or maybe just inline below?

https://github.com/llvm/llvm-project/pull/222908