[llvm] [SandboxVectorizer] Add container class to track and manage SeedBundles (PR #112048)

[via llvm-commits]

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@@ -162,5 +169,107 @@ template <typename LoadOrStoreT> class MemSeedBundle : public SeedBundle {
 using StoreSeedBundle = MemSeedBundle<sandboxir::StoreInst>;
 using LoadSeedBundle = MemSeedBundle<sandboxir::LoadInst>;
 
+/// Class to conveniently track Seeds within Seedbundles. Saves newly collected
+/// seeds in the proper bundle. Supports constant-time removal, as seeds and
+/// entire bundles are vectorized and marked used to signify removal. Iterators
+/// skip bundles that are completely used.
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vporpo wrote:

Ah yes you are referring to the `used` flag. I was thinking of something tagged with the `used` flag as unused.

https://github.com/llvm/llvm-project/pull/112048