[llvm] [SandboxVec][BottomUpVec] Add cost estimation and tr-accept-or-revert pass (PR #124620)

[via llvm-commits]

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@@ -92,11 +92,14 @@ class Region {
   /// All the instructions in the Region. Only new instructions generated during
   /// vectorization are part of the Region.
   SetVector<Instruction *> Insts;
+  /// An auxiliary sequence of Instruction-Index pairs.
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vporpo wrote:

I added a small paragraph at the bottom of the class description.

https://github.com/llvm/llvm-project/pull/124620