[llvm] [SLP] Use named structs in vectorizeStores() (NFC) (PR #132781)

[Alexey Bataev via llvm-commits]

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@@ -19923,31 +19923,51 @@ bool SLPVectorizerPass::vectorizeStores(
   BoUpSLP::ValueSet VectorizedStores;
   bool Changed = false;
 
+  /// A store instruction and the distance of its address to a base pointer.
+  struct CandidateInstr {
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alexey-bataev wrote:

`StoreInstIndexAndDistance`?

https://github.com/llvm/llvm-project/pull/132781