addressed review comments.

Author: Mikhail Gudim

llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp

@@ -2245,6 +2245,21 @@ class BoUpSLP {
                      Align Alignment, const int64_t Diff, Value *Ptr0,
                      Value *PtrN, StridedPtrInfo &SPtrInfo) const;
 
+  /// Return true if an array of scalar loads can be replaced with a strided
+  /// load (with run-time stride).
+  /// \param PointerOps list of pointer arguments of loads.
+  /// \param ScalarTy type of loads.
+  /// \param CommonAlignment common alignement of loads as computed by
+  /// `computeCommonAlignment<LoadInst>`.
+  /// \param SortedIndicies is a list of indicies computed by this function such
+  /// that the sequence `PointerOps[SortedIndices[0]],
+  /// PointerOps[SortedIndicies[1]], ..., PointerOps[SortedIndices[n]]` is
+  /// ordered by the coefficient of the stride. For example, if PointerOps is
+  /// `%base + %stride, %base, %base + 2 * stride` the `SortedIndices` will be
+  /// `[1, 0, 2]`. We follow the convention that if `SortedIndices` has to be
+  /// `0, 1, 2, 3, ...` we return empty vector for `SortedIndicies`.
+  /// \param SPtrInfo If the function return `true`, it also sets all the fields
+  /// of `SPtrInfo` necessary to generate the strided load later.
   bool analyzeRtStrideCandidate(ArrayRef<Value *> PointerOps, Type *ScalarTy,
                                 Align CommonAlignment,
                                 SmallVectorImpl<unsigned> &SortedIndices,
@@ -6888,8 +6903,8 @@ bool BoUpSLP::analyzeRtStrideCandidate(ArrayRef<Value *> PointerOps,
   // TODO: VecSz may change if we widen the strided load.
   unsigned VecSz = Sz;
   FixedVectorType *StridedLoadTy = getWidenedType(ScalarTy, VecSz);
-  if (!(Sz > MinProfitableStridedLoads && TTI->isTypeLegal(StridedLoadTy) &&
-        TTI->isLegalStridedLoadStore(StridedLoadTy, CommonAlignment)))
+  if (Sz <= MinProfitableStridedLoads || !TTI->isTypeLegal(StridedLoadTy) ||
+      !TTI->isLegalStridedLoadStore(StridedLoadTy, CommonAlignment))
     return false;
   if (const SCEV *Stride =
           calculateRtStride(PointerOps, ScalarTy, *DL, *SE, SortedIndices)) {