[NewPM] Remove GuardWideningLegacyPass (#72810)

This legacy pass isn't used anywhere and there is no test coverage, so
at this point it should be removed.

Author: boomanaiden154

llvm/include/llvm/InitializePasses.h

@@ -129,8 +129,7 @@ void initializeGCMachineCodeAnalysisPass(PassRegistry&);
 void initializeGCModuleInfoPass(PassRegistry&);
 void initializeGVNLegacyPassPass(PassRegistry&);
 void initializeGlobalMergePass(PassRegistry&);
-void initializeGlobalsAAWrapperPassPass(PassRegistry&);
-void initializeGuardWideningLegacyPassPass(PassRegistry&);
+void initializeGlobalsAAWrapperPassPass(PassRegistry &);
 void initializeHardwareLoopsLegacyPass(PassRegistry&);
 void initializeMIRProfileLoaderPassPass(PassRegistry &);
 void initializeIRSimilarityIdentifierWrapperPassPass(PassRegistry&);

llvm/include/llvm/LinkAllPasses.h

@@ -80,7 +80,6 @@ namespace {
       (void) llvm::createDomViewerWrapperPassPass();
       (void) llvm::createAlwaysInlinerLegacyPass();
       (void) llvm::createGlobalsAAWrapperPass();
-      (void) llvm::createGuardWideningPass();
       (void) llvm::createLoopGuardWideningPass();
       (void) llvm::createInstSimplifyLegacyPass();
       (void) llvm::createInstructionCombiningPass();

llvm/include/llvm/Transforms/Scalar.h

@@ -39,16 +39,6 @@ Pass *createRedundantDbgInstEliminationPass();
 //
 FunctionPass *createDeadCodeEliminationPass();
 
-
-//===----------------------------------------------------------------------===//
-//
-// GuardWidening - An optimization over the @llvm.experimental.guard intrinsic
-// that (optimistically) combines multiple guards into one to have fewer checks
-// at runtime.
-//
-FunctionPass *createGuardWideningPass();
-
-
 //===----------------------------------------------------------------------===//
 //
 // LoopGuardWidening - Analogous to the GuardWidening pass, but restricted to a

llvm/lib/Transforms/Scalar/GuardWidening.cpp

@@ -1015,40 +1015,7 @@ PreservedAnalyses GuardWideningPass::run(Loop &L, LoopAnalysisManager &AM,
 }
 
 namespace {
-struct GuardWideningLegacyPass : public FunctionPass {
-  static char ID;
-
-  GuardWideningLegacyPass() : FunctionPass(ID) {
-    initializeGuardWideningLegacyPassPass(*PassRegistry::getPassRegistry());
-  }
-
-  bool runOnFunction(Function &F) override {
-    if (skipFunction(F))
-      return false;
-    auto &DT = getAnalysis<DominatorTreeWrapperPass>().getDomTree();
-    auto &LI = getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
-    auto &AC = getAnalysis<AssumptionCacheTracker>().getAssumptionCache(F);
-    auto &PDT = getAnalysis<PostDominatorTreeWrapperPass>().getPostDomTree();
-    auto *MSSAWP = getAnalysisIfAvailable<MemorySSAWrapperPass>();
-    std::unique_ptr<MemorySSAUpdater> MSSAU;
-    if (MSSAWP)
-      MSSAU = std::make_unique<MemorySSAUpdater>(&MSSAWP->getMSSA());
-    return GuardWideningImpl(DT, &PDT, LI, AC, MSSAU ? MSSAU.get() : nullptr,
-                             DT.getRootNode(),
-                             [](BasicBlock *) { return true; })
-        .run();
-  }
-
-  void getAnalysisUsage(AnalysisUsage &AU) const override {
-    AU.setPreservesCFG();
-    AU.addRequired<DominatorTreeWrapperPass>();
-    AU.addRequired<PostDominatorTreeWrapperPass>();
-    AU.addRequired<LoopInfoWrapperPass>();
-    AU.addPreserved<MemorySSAWrapperPass>();
-  }
-};
-
-/// Same as above, but restricted to a single loop at a time.  Can be
+/// Restricted to a single loop at a time.  Can be
 /// scheduled with other loop passes w/o breaking out of LPM
 struct LoopGuardWideningLegacyPass : public LoopPass {
   static char ID;
@@ -1091,17 +1058,8 @@ struct LoopGuardWideningLegacyPass : public LoopPass {
 };
 }
 
-char GuardWideningLegacyPass::ID = 0;
 char LoopGuardWideningLegacyPass::ID = 0;
 
-INITIALIZE_PASS_BEGIN(GuardWideningLegacyPass, "guard-widening", "Widen guards",
-                      false, false)
-INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
-INITIALIZE_PASS_DEPENDENCY(PostDominatorTreeWrapperPass)
-INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass)
-INITIALIZE_PASS_END(GuardWideningLegacyPass, "guard-widening", "Widen guards",
-                    false, false)
-
 INITIALIZE_PASS_BEGIN(LoopGuardWideningLegacyPass, "loop-guard-widening",
                       "Widen guards (within a single loop, as a loop pass)",
                       false, false)
@@ -1112,10 +1070,6 @@ INITIALIZE_PASS_END(LoopGuardWideningLegacyPass, "loop-guard-widening",
                     "Widen guards (within a single loop, as a loop pass)",
                     false, false)
 
-FunctionPass *llvm::createGuardWideningPass() {
-  return new GuardWideningLegacyPass();
-}
-
 Pass *llvm::createLoopGuardWideningPass() {
   return new LoopGuardWideningLegacyPass();
 }

llvm/lib/Transforms/Scalar/Scalar.cpp

@@ -22,7 +22,6 @@ void llvm::initializeScalarOpts(PassRegistry &Registry) {
   initializeConstantHoistingLegacyPassPass(Registry);
   initializeDCELegacyPassPass(Registry);
   initializeScalarizerLegacyPassPass(Registry);
-  initializeGuardWideningLegacyPassPass(Registry);
   initializeLoopGuardWideningLegacyPassPass(Registry);
   initializeGVNLegacyPassPass(Registry);
   initializeEarlyCSELegacyPassPass(Registry);