[llvm] [SLP] Use costing to decide between Strided Loads and Compressed Loads (PR #226540)

[Alexey Bataev via llvm-commits]

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@@ -61,6 +73,55 @@ InstructionCost getShuffleCost(const TargetTransformInfo &TTI,
                             /*CtxI=*/nullptr, VIC);
 }
 
+InstructionCost getStridedLoadCost(const TargetTransformInfo &TTI,
+                                   const DataLayout &DL, Value *StrideVal,
+                                   Type *StridedLoadTy, Type *VecTy, Value *Ptr,
+                                   Align CommonAlignment,
+                                   TargetTransformInfo::CastContextHint Ctx,
+                                   TargetTransformInfo::TargetCostKind CostKind,
+                                   bool IsReverse) {
+  Value *Stride = getStrideBytesIfConstant(StrideVal, VecTy->getScalarType(),
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alexey-bataev wrote:

```suggestion
  Value *Stride = getStrideBytesIfConstant(StrideVal, ScalarTy,
```
To handle revec

https://github.com/llvm/llvm-project/pull/226540