[llvm] [SLP] More accurately cost RISCV scalar splats (PR #213104)

[Luke Lau via llvm-commits]

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@@ -1046,14 +1050,15 @@ InstructionCost TargetTransformInfo::getAltInstrCost(
 InstructionCost TargetTransformInfo::getShuffleCost(
     ShuffleKind Kind, VectorType *DstTy, VectorType *SrcTy, ArrayRef<int> Mask,
     TTI::TargetCostKind CostKind, int Index, VectorType *SubTp,
-    ArrayRef<const Value *> Args, const Instruction *CxtI) const {
+    ArrayRef<const Value *> Args, const Instruction *CxtI,
+    TTI::VectorInstrContext VIC) const {
   assert((Mask.empty() || DstTy->isScalableTy() ||
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lukel97 wrote:

Can we add an assert that `VIC == SplatOpFolded` only for the broadcast ShuffleKind?

https://github.com/llvm/llvm-project/pull/213104