[llvm] [RISCV][TTI] Recognize CONCAT_VECTORS if a shufflevector mask is multiple insert subvector. (PR #111459)

[Luke Lau via llvm-commits]

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@@ -343,6 +343,28 @@ RISCVTTIImpl::getConstantPoolLoadCost(Type *Ty,  TTI::TargetCostKind CostKind) {
                              /*AddressSpace=*/0, CostKind);
 }
 
+static bool isRepeatedConcatMaskImpl(ArrayRef<int> Mask, int &SubVectorSize) {
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lukel97 wrote:

Nit, you can drop the Impl if there's no other wrapper function
```suggestion
static bool isRepeatedConcatMask(ArrayRef<int> Mask, int &SubVectorSize) {
```

https://github.com/llvm/llvm-project/pull/111459