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

[Thorsten Schütt via llvm-commits]

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@@ -54,6 +54,10 @@ class SeedBundle {
     NumUnusedBits += Utils::getNumBits(I);
   }
 
+  virtual void insert(Instruction *I, ScalarEvolution &SE) {
+    assert("Subclasses must override this function.");
+  }
+
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tschuett wrote:

If you debate about `=0`, assert, and `llvm_unreachable`, how about introducing `SeedBundleBase` and `SeedBundle`? Then you can have the `=0`.

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