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

[Jorge Gorbe Moya 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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slackito wrote:

Now that we have, in the aux vector, an extra way in which information can flow from one pass to the next, we should document very carefully what each pass expects to get there. This class should have a documentation comment anyway, so please add that and describe what needs to be passed in the aux vector.

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