[llvm] [SandboxVec] Add BottomUpVec test flag to build regions from metadata. (PR #111904)

[Arthur Eubanks via llvm-commits]

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@@ -29,10 +29,11 @@ class BottomUpVec final : public FunctionPass {
   void tryVectorize(ArrayRef<Value *> Seeds);
 
   // The PM containing the pipeline of region passes.
-  RegionPassManager RPM;
+  // TODO: Remove maybe_unused once we build regions to run passes on.
+  [[maybe_unused]] RegionPassManager *RPM;
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aeubanks wrote:

can this be a reference?

https://github.com/llvm/llvm-project/pull/111904