[llvm] [SandboxVec] Move seed collection into its own separate pass (PR #127132)

[via llvm-commits]

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@@ -16,14 +16,13 @@
 #include "llvm/ADT/StringRef.h"
 #include "llvm/SandboxIR/Constant.h"
 #include "llvm/SandboxIR/Pass.h"
-#include "llvm/SandboxIR/PassManager.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Transforms/Vectorize/SandboxVectorizer/InstrMaps.h"
 #include "llvm/Transforms/Vectorize/SandboxVectorizer/Legality.h"
 
 namespace llvm::sandboxir {
 
-class BottomUpVec final : public FunctionPass {
+class BottomUpVec final : public RegionPass {
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vporpo wrote:

Yes, that's a great point. Even though it is safe to run the pass without having set the Aux vector, it really expects it to be populated. I am wondering if there is a more structured way of expressing this, perhaps using a different subclass of the RegionPass?

https://github.com/llvm/llvm-project/pull/127132