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

[Gaëtan Bossu via llvm-commits]

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@@ -884,6 +884,42 @@ class InstructionsState {
   static InstructionsState invalid() { return {nullptr, nullptr}; }
 };
 
+/// A reference to a ld/st instruction and the distance of its address to a base
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gbossu wrote:

Would you be opposed to leaving the code this way? I'm not familiar with the code yet, but it seems that loads also get sorted by distance, at least in some code paths. So I don't think it would hurt to leave the door open to more code sharing.

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