[llvm] ae0c203 - [LoopLoadElimination] Remove legacy pass

[Fangrui Song via llvm-commits]

Author: Fangrui Song
Date: 2023-02-14T16:00:49-08:00
New Revision: ae0c203e676ef0b3550cb367ad9a42ce442d332e

URL: https://github.com/llvm/llvm-project/commit/ae0c203e676ef0b3550cb367ad9a42ce442d332e
DIFF: https://github.com/llvm/llvm-project/commit/ae0c203e676ef0b3550cb367ad9a42ce442d332e.diff

LOG: [LoopLoadElimination] Remove legacy pass

Following recent changes to remove non-core features of the legacy PM/optimization pipeline.

Added: 
    

Modified: 
    llvm/include/llvm/InitializePasses.h
    llvm/include/llvm/Transforms/Scalar.h
    llvm/lib/Transforms/IPO/PassManagerBuilder.cpp
    llvm/lib/Transforms/Scalar/LoopLoadElimination.cpp
    llvm/lib/Transforms/Scalar/Scalar.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/include/llvm/InitializePasses.h b/llvm/include/llvm/InitializePasses.h
index e0c1f49893e4..39a5da542737 100644
--- a/llvm/include/llvm/InitializePasses.h
+++ b/llvm/include/llvm/InitializePasses.h
@@ -215,7 +215,6 @@ void initializeLoopInfoWrapperPassPass(PassRegistry&);
 void initializeLoopInstSimplifyLegacyPassPass(PassRegistry&);
 void initializeLoopInterchangeLegacyPassPass(PassRegistry &);
 void initializeLoopFlattenLegacyPassPass(PassRegistry&);
-void initializeLoopLoadEliminationPass(PassRegistry&);
 void initializeLoopPassPass(PassRegistry&);
 void initializeLoopPredicationLegacyPassPass(PassRegistry&);
 void initializeLoopRerollLegacyPassPass(PassRegistry &);

diff  --git a/llvm/include/llvm/Transforms/Scalar.h b/llvm/include/llvm/Transforms/Scalar.h
index 7bac07f2f1ba..1821fa683d96 100644
--- a/llvm/include/llvm/Transforms/Scalar.h
+++ b/llvm/include/llvm/Transforms/Scalar.h
@@ -484,12 +484,6 @@ FunctionPass *createNaryReassociatePass();
 //
 FunctionPass *createLoopFusePass();
 
-//===----------------------------------------------------------------------===//
-//
-// LoopLoadElimination - Perform loop-aware load elimination.
-//
-FunctionPass *createLoopLoadEliminationPass();
-
 //===----------------------------------------------------------------------===//
 //
 // LoopVersioning - Perform loop multi-versioning.

diff  --git a/llvm/lib/Transforms/IPO/PassManagerBuilder.cpp b/llvm/lib/Transforms/IPO/PassManagerBuilder.cpp
index 42849e940409..a8c4eb2ee36b 100644
--- a/llvm/lib/Transforms/IPO/PassManagerBuilder.cpp
+++ b/llvm/lib/Transforms/IPO/PassManagerBuilder.cpp
@@ -216,11 +216,6 @@ void PassManagerBuilder::addVectorPasses(legacy::PassManagerBase &PM,
                                 ForgetAllSCEVInLoopUnroll));
   }
 
-  if (!IsFullLTO) {
-    // Eliminate loads by forwarding stores from the previous iteration to loads
-    // of the current iteration.
-    PM.add(createLoopLoadEliminationPass());
-  }
   // Cleanup after the loop optimization passes.
   PM.add(createInstructionCombiningPass());
 

diff  --git a/llvm/lib/Transforms/Scalar/LoopLoadElimination.cpp b/llvm/lib/Transforms/Scalar/LoopLoadElimination.cpp
index b615a0a0a9c0..5f80f382c68b 100644
--- a/llvm/lib/Transforms/Scalar/LoopLoadElimination.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopLoadElimination.cpp
@@ -658,70 +658,6 @@ static bool eliminateLoadsAcrossLoops(Function &F, LoopInfo &LI,
   return Changed;
 }
 
-namespace {
-
-/// The pass.  Most of the work is delegated to the per-loop
-/// LoadEliminationForLoop class.
-class LoopLoadElimination : public FunctionPass {
-public:
-  static char ID;
-
-  LoopLoadElimination() : FunctionPass(ID) {
-    initializeLoopLoadEliminationPass(*PassRegistry::getPassRegistry());
-  }
-
-  bool runOnFunction(Function &F) override {
-    if (skipFunction(F))
-      return false;
-
-    auto &LI = getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
-    auto &LAIs = getAnalysis<LoopAccessLegacyAnalysis>().getLAIs();
-    auto &DT = getAnalysis<DominatorTreeWrapperPass>().getDomTree();
-    auto *PSI = &getAnalysis<ProfileSummaryInfoWrapperPass>().getPSI();
-    auto *BFI = (PSI && PSI->hasProfileSummary()) ?
-                &getAnalysis<LazyBlockFrequencyInfoPass>().getBFI() :
-                nullptr;
-    auto *SE = &getAnalysis<ScalarEvolutionWrapperPass>().getSE();
-
-    // Process each loop nest in the function.
-    return eliminateLoadsAcrossLoops(F, LI, DT, BFI, PSI, SE, /*AC*/ nullptr,
-                                     LAIs);
-  }
-
-  void getAnalysisUsage(AnalysisUsage &AU) const override {
-    AU.addRequiredID(LoopSimplifyID);
-    AU.addRequired<LoopInfoWrapperPass>();
-    AU.addPreserved<LoopInfoWrapperPass>();
-    AU.addRequired<LoopAccessLegacyAnalysis>();
-    AU.addRequired<ScalarEvolutionWrapperPass>();
-    AU.addRequired<DominatorTreeWrapperPass>();
-    AU.addPreserved<DominatorTreeWrapperPass>();
-    AU.addPreserved<GlobalsAAWrapperPass>();
-    AU.addRequired<ProfileSummaryInfoWrapperPass>();
-    LazyBlockFrequencyInfoPass::getLazyBFIAnalysisUsage(AU);
-  }
-};
-
-} // end anonymous namespace
-
-char LoopLoadElimination::ID;
-
-static const char LLE_name[] = "Loop Load Elimination";
-
-INITIALIZE_PASS_BEGIN(LoopLoadElimination, LLE_OPTION, LLE_name, false, false)
-INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass)
-INITIALIZE_PASS_DEPENDENCY(LoopAccessLegacyAnalysis)
-INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
-INITIALIZE_PASS_DEPENDENCY(ScalarEvolutionWrapperPass)
-INITIALIZE_PASS_DEPENDENCY(LoopSimplify)
-INITIALIZE_PASS_DEPENDENCY(ProfileSummaryInfoWrapperPass)
-INITIALIZE_PASS_DEPENDENCY(LazyBlockFrequencyInfoPass)
-INITIALIZE_PASS_END(LoopLoadElimination, LLE_OPTION, LLE_name, false, false)
-
-FunctionPass *llvm::createLoopLoadEliminationPass() {
-  return new LoopLoadElimination();
-}
-
 PreservedAnalyses LoopLoadEliminationPass::run(Function &F,
                                                FunctionAnalysisManager &AM) {
   auto &LI = AM.getResult<LoopAnalysis>(F);

diff  --git a/llvm/lib/Transforms/Scalar/Scalar.cpp b/llvm/lib/Transforms/Scalar/Scalar.cpp
index 11f819eb4b6e..dd1343389d55 100644
--- a/llvm/lib/Transforms/Scalar/Scalar.cpp
+++ b/llvm/lib/Transforms/Scalar/Scalar.cpp
@@ -104,7 +104,6 @@ void llvm::initializeScalarOpts(PassRegistry &Registry) {
   initializePlaceBackedgeSafepointsImplPass(Registry);
   initializePlaceSafepointsPass(Registry);
   initializeFloat2IntLegacyPassPass(Registry);
-  initializeLoopLoadEliminationPass(Registry);
   initializeLoopSimplifyCFGLegacyPassPass(Registry);
   initializeLoopVersioningLegacyPassPass(Registry);
 }