[NewPM] Remove Legacy RedudantDbgInstEliminationPass (llvm#73405)

This pass isn't used by anywhere upstream and thus has no test coverage.
For these reasons, remove it.

Author: boomanaiden154

llvm/include/llvm/InitializePasses.h

@@ -250,7 +250,6 @@ void initializePseudoProbeInserterPass(PassRegistry &);
 void initializeRAGreedyPass(PassRegistry&);
 void initializeReachingDefAnalysisPass(PassRegistry&);
 void initializeReassociateLegacyPassPass(PassRegistry&);
-void initializeRedundantDbgInstEliminationPass(PassRegistry&);
 void initializeRegAllocEvictionAdvisorAnalysisPass(PassRegistry &);
 void initializeRegAllocFastPass(PassRegistry&);
 void initializeRegAllocPriorityAdvisorAnalysisPass(PassRegistry &);

llvm/include/llvm/LinkAllPasses.h

@@ -102,7 +102,6 @@ namespace {
       (void)llvm::createPostDomOnlyViewerWrapperPassPass();
       (void)llvm::createPostDomViewerWrapperPassPass();
       (void) llvm::createReassociatePass();
-      (void) llvm::createRedundantDbgInstEliminationPass();
       (void) llvm::createRegionInfoPass();
       (void) llvm::createRegionOnlyPrinterPass();
       (void) llvm::createRegionOnlyViewerPass();

llvm/include/llvm/Transforms/Scalar.h

@@ -23,13 +23,6 @@ class Function;
 class FunctionPass;
 class Pass;
 
-//===----------------------------------------------------------------------===//
-//
-// RedundantDbgInstElimination - This pass removes redundant dbg intrinsics
-// without modifying the CFG of the function.  It is a FunctionPass.
-//
-Pass *createRedundantDbgInstEliminationPass();
-
 //===----------------------------------------------------------------------===//
 //
 // DeadCodeElimination - This pass is more powerful than DeadInstElimination,

llvm/lib/Transforms/Scalar/DCE.cpp

@@ -36,39 +36,6 @@ STATISTIC(DCEEliminated, "Number of insts removed");
 DEBUG_COUNTER(DCECounter, "dce-transform",
               "Controls which instructions are eliminated");
 
-//===--------------------------------------------------------------------===//
-// RedundantDbgInstElimination pass implementation
-//
-
-namespace {
-struct RedundantDbgInstElimination : public FunctionPass {
-  static char ID; // Pass identification, replacement for typeid
-  RedundantDbgInstElimination() : FunctionPass(ID) {
-    initializeRedundantDbgInstEliminationPass(*PassRegistry::getPassRegistry());
-  }
-  bool runOnFunction(Function &F) override {
-    if (skipFunction(F))
-      return false;
-    bool Changed = false;
-    for (auto &BB : F)
-      Changed |= RemoveRedundantDbgInstrs(&BB);
-    return Changed;
-  }
-
-  void getAnalysisUsage(AnalysisUsage &AU) const override {
-    AU.setPreservesCFG();
-  }
-};
-}
-
-char RedundantDbgInstElimination::ID = 0;
-INITIALIZE_PASS(RedundantDbgInstElimination, "redundant-dbg-inst-elim",
-                "Redundant Dbg Instruction Elimination", false, false)
-
-Pass *llvm::createRedundantDbgInstEliminationPass() {
-  return new RedundantDbgInstElimination();
-}
-
 PreservedAnalyses
 RedundantDbgInstEliminationPass::run(Function &F, FunctionAnalysisManager &AM) {
   bool Changed = false;

llvm/lib/Transforms/Scalar/Scalar.cpp

@@ -38,7 +38,6 @@ void llvm::initializeScalarOpts(PassRegistry &Registry) {
   initializeNaryReassociateLegacyPassPass(Registry);
   initializePartiallyInlineLibCallsLegacyPassPass(Registry);
   initializeReassociateLegacyPassPass(Registry);
-  initializeRedundantDbgInstEliminationPass(Registry);
   initializeScalarizeMaskedMemIntrinLegacyPassPass(Registry);
   initializeSROALegacyPassPass(Registry);
   initializeCFGSimplifyPassPass(Registry);