[llvm] [SLPVectorizer][NFC] Refactor `canVectorizeLoads`. (PR #157911)

[Alexey Bataev via llvm-commits]

================
@@ -6830,23 +6861,44 @@ static bool isStridedLoad(ArrayRef<Value *> VL, ArrayRef<Value *> PointerOps,
       if (Ptr == PtrN)
         Dist = Diff;
       else if (Ptr != Ptr0)
-        Dist = *getPointersDiff(ScalarTy, Ptr0, ScalarTy, Ptr, DL, SE);
+        Dist = *getPointersDiff(ElemTy, Ptr0, ElemTy, Ptr, *DL, *SE);
       // If the strides are not the same or repeated, we can't
       // vectorize.
       if (((Dist / Stride) * Stride) != Dist || !Dists.insert(Dist).second)
         break;
     }
-    if (Dists.size() == Sz)
+    if (Dists.size() == Sz) {
+      Type *StrideTy = DL->getIndexType(Ptr0->getType());
+      SPtrInfo.StrideVal = ConstantInt::get(StrideTy, Stride);
+      SPtrInfo.Ty = StridedLoadTy;
       return true;
+    }
   }
   return false;
 }
 
-BoUpSLP::LoadsState
-BoUpSLP::canVectorizeLoads(ArrayRef<Value *> VL, const Value *VL0,
-                           SmallVectorImpl<unsigned> &Order,
-                           SmallVectorImpl<Value *> &PointerOps,
-                           unsigned *BestVF, bool TryRecursiveCheck) const {
+bool BoUpSLP::analyzeRtStrideCandidate(ArrayRef<Value *> PointerOps,
+                                       Type *ElemTy, Align CommonAlignment,
+                                       SmallVectorImpl<unsigned> &SortedIndices,
+                                       StridedPtrInfo &SPtrInfo) const {
+  const size_t Sz = PointerOps.size();
+  FixedVectorType *VecTy = getWidenedType(ElemTy, Sz);
----------------
alexey-bataev wrote:

```suggestion
  auto *VecTy = getWidenedType(ElemTy, Sz);
```

https://github.com/llvm/llvm-project/pull/157911