Commit 90e630a9 authored by Teresa Johnson's avatar Teresa Johnson
Browse files

Revert "[LTO/WPD] Enable aggressive WPD under LTO option" 

This reverts commit 59733525.

There is a windows sanitizer bot failure in one of the cfi tests
that I will need some time to figure out:
http://lab.llvm.org:8011/builders/sanitizer-windows/builds/57155/steps/stage%201%20check/logs/stdio
parent 69bf40c4

clang/lib/CodeGen/BackendUtil.cpp

+0 −32
Original line number Diff line number Diff line
@@ -51,7 +51,6 @@ 
#include "llvm/Transforms/Coroutines.h"

#include "llvm/Transforms/IPO.h"

#include "llvm/Transforms/IPO/AlwaysInliner.h"

#include "llvm/Transforms/IPO/LowerTypeTests.h"

#include "llvm/Transforms/IPO/PassManagerBuilder.h"

#include "llvm/Transforms/IPO/ThinLTOBitcodeWriter.h"

#include "llvm/Transforms/InstCombine/InstCombine.h"
@@ -554,16 +553,6 @@ void EmitAssemblyHelper::CreatePasses(legacy::PassManager &MPM, 
  std::unique_ptr<TargetLibraryInfoImpl> TLII(

      createTLII(TargetTriple, CodeGenOpts));



  // If we reached here with a non-empty index file name, then the index file

  // was empty and we are not performing ThinLTO backend compilation (used in

  // testing in a distributed build environment). Drop any the type test

  // assume sequences inserted for whole program vtables so that codegen doesn't

  // complain.

  if (!CodeGenOpts.ThinLTOIndexFile.empty())

    MPM.add(createLowerTypeTestsPass(/*ExportSummary=*/nullptr,

                                     /*ImportSummary=*/nullptr,

                                     /*DropTypeTests=*/true));



  PassManagerBuilderWrapper PMBuilder(TargetTriple, CodeGenOpts, LangOpts);



  // At O0 and O1 we only run the always inliner which is more efficient. At
@@ -1125,15 +1114,6 @@ void EmitAssemblyHelper::EmitAssemblyWithNewPassManager( 
    bool IsLTO = CodeGenOpts.PrepareForLTO;



    if (CodeGenOpts.OptimizationLevel == 0) {

      // If we reached here with a non-empty index file name, then the index

      // file was empty and we are not performing ThinLTO backend compilation

      // (used in testing in a distributed build environment). Drop any the type

      // test assume sequences inserted for whole program vtables so that

      // codegen doesn't complain.

      if (!CodeGenOpts.ThinLTOIndexFile.empty())

        MPM.addPass(LowerTypeTestsPass(/*ExportSummary=*/nullptr,

                                       /*ImportSummary=*/nullptr,

                                       /*DropTypeTests=*/true));

      if (Optional<GCOVOptions> Options = getGCOVOptions(CodeGenOpts))

        MPM.addPass(GCOVProfilerPass(*Options));

      if (Optional<InstrProfOptions> Options =
@@ -1170,18 +1150,6 @@ void EmitAssemblyHelper::EmitAssemblyWithNewPassManager( 
      // configure the pipeline.

      PassBuilder::OptimizationLevel Level = mapToLevel(CodeGenOpts);



      // If we reached here with a non-empty index file name, then the index

      // file was empty and we are not performing ThinLTO backend compilation

      // (used in testing in a distributed build environment). Drop any the type

      // test assume sequences inserted for whole program vtables so that

      // codegen doesn't complain.

      if (!CodeGenOpts.ThinLTOIndexFile.empty())

        PB.registerPipelineStartEPCallback([](ModulePassManager &MPM) {

          MPM.addPass(LowerTypeTestsPass(/*ExportSummary=*/nullptr,

                                         /*ImportSummary=*/nullptr,

                                         /*DropTypeTests=*/true));

        });



      PB.registerPipelineStartEPCallback([](ModulePassManager &MPM) {

        MPM.addPass(createModuleToFunctionPassAdaptor(

            EntryExitInstrumenterPass(/*PostInlining=*/false)));

clang/lib/CodeGen/CGClass.cpp

+1 −3
Original line number Diff line number Diff line
@@ -2641,9 +2641,7 @@ void CodeGenFunction::EmitTypeMetadataCodeForVCall(const CXXRecordDecl *RD, 
  if (SanOpts.has(SanitizerKind::CFIVCall))

    EmitVTablePtrCheckForCall(RD, VTable, CodeGenFunction::CFITCK_VCall, Loc);

  else if (CGM.getCodeGenOpts().WholeProgramVTables &&

           // Don't insert type test assumes if we are forcing public std

           // visibility.

           !CGM.HasLTOVisibilityPublicStd(RD)) {

           CGM.HasHiddenLTOVisibility(RD)) {

    llvm::Metadata *MD =

        CGM.CreateMetadataIdentifierForType(QualType(RD->getTypeForDecl(), 0));

    llvm::Value *TypeId =

clang/lib/CodeGen/CGVTables.cpp

+16 −21
Original line number Diff line number Diff line
@@ -1011,26 +1011,6 @@ void CodeGenModule::EmitDeferredVTables() { 
  DeferredVTables.clear();

}



bool CodeGenModule::HasLTOVisibilityPublicStd(const CXXRecordDecl *RD) {

  if (!getCodeGenOpts().LTOVisibilityPublicStd)

    return false;



  const DeclContext *DC = RD;

  while (1) {

    auto *D = cast<Decl>(DC);

    DC = DC->getParent();

    if (isa<TranslationUnitDecl>(DC->getRedeclContext())) {

      if (auto *ND = dyn_cast<NamespaceDecl>(D))

        if (const IdentifierInfo *II = ND->getIdentifier())

          if (II->isStr("std") || II->isStr("stdext"))

            return true;

      break;

    }

  }



  return false;

}



bool CodeGenModule::HasHiddenLTOVisibility(const CXXRecordDecl *RD) {

  LinkageInfo LV = RD->getLinkageAndVisibility();

  if (!isExternallyVisible(LV.getLinkage()))
@@ -1047,7 +1027,22 @@ bool CodeGenModule::HasHiddenLTOVisibility(const CXXRecordDecl *RD) { 
      return false;

  }



  return !HasLTOVisibilityPublicStd(RD);

  if (getCodeGenOpts().LTOVisibilityPublicStd) {

    const DeclContext *DC = RD;

    while (1) {

      auto *D = cast<Decl>(DC);

      DC = DC->getParent();

      if (isa<TranslationUnitDecl>(DC->getRedeclContext())) {

        if (auto *ND = dyn_cast<NamespaceDecl>(D))

          if (const IdentifierInfo *II = ND->getIdentifier())

            if (II->isStr("std") || II->isStr("stdext"))

              return false;

        break;

      }

    }

  }



  return true;

}



llvm::GlobalObject::VCallVisibility

clang/lib/CodeGen/CodeGenModule.h

+0 −5
Original line number Diff line number Diff line
@@ -1292,11 +1292,6 @@ public: 
  /// optimization.

  bool HasHiddenLTOVisibility(const CXXRecordDecl *RD);



  /// Returns whether the given record has public std LTO visibility

  /// and therefore may not participate in (single-module) CFI and whole-program

  /// vtable optimization.

  bool HasLTOVisibilityPublicStd(const CXXRecordDecl *RD);



  /// Returns the vcall visibility of the given type. This is the scope in which

  /// a virtual function call could be made which ends up being dispatched to a

  /// member function of this class. This scope can be wider than the visibility

clang/lib/CodeGen/ItaniumCXXABI.cpp

+4 −10
Original line number Diff line number Diff line
@@ -670,10 +670,6 @@ CGCallee ItaniumCXXABI::EmitLoadOfMemberFunctionPointer( 
                            CGM.HasHiddenLTOVisibility(RD);

  bool ShouldEmitVFEInfo = CGM.getCodeGenOpts().VirtualFunctionElimination &&

                           CGM.HasHiddenLTOVisibility(RD);

  bool ShouldEmitWPDInfo =

      CGM.getCodeGenOpts().WholeProgramVTables &&

      // Don't insert type tests if we are forcing public std visibility.

      !CGM.HasLTOVisibilityPublicStd(RD);

  llvm::Value *VirtualFn = nullptr;



  {
@@ -681,9 +677,8 @@ CGCallee ItaniumCXXABI::EmitLoadOfMemberFunctionPointer( 
    llvm::Value *TypeId = nullptr;

    llvm::Value *CheckResult = nullptr;



    if (ShouldEmitCFICheck || ShouldEmitVFEInfo || ShouldEmitWPDInfo) {

      // If doing CFI, VFE or WPD, we will need the metadata node to check

      // against.

    if (ShouldEmitCFICheck || ShouldEmitVFEInfo) {

      // If doing CFI or VFE, we will need the metadata node to check against.

      llvm::Metadata *MD =

          CGM.CreateMetadataIdentifierForVirtualMemPtrType(QualType(MPT, 0));

      TypeId = llvm::MetadataAsValue::get(CGF.getLLVMContext(), MD);
@@ -707,7 +702,7 @@ CGCallee ItaniumCXXABI::EmitLoadOfMemberFunctionPointer( 
    } else {

      // When not doing VFE, emit a normal load, as it allows more

      // optimisations than type.checked.load.

      if (ShouldEmitCFICheck || ShouldEmitWPDInfo) {

      if (ShouldEmitCFICheck) {

        CheckResult = Builder.CreateCall(

            CGM.getIntrinsic(llvm::Intrinsic::type_test),

            {Builder.CreateBitCast(VFPAddr, CGF.Int8PtrTy), TypeId});
@@ -718,8 +713,7 @@ CGCallee ItaniumCXXABI::EmitLoadOfMemberFunctionPointer( 
                                            "memptr.virtualfn");

    }

    assert(VirtualFn && "Virtual fuction pointer not created!");

    assert((!ShouldEmitCFICheck || !ShouldEmitVFEInfo || !ShouldEmitWPDInfo ||

            CheckResult) &&

    assert((!ShouldEmitCFICheck || !ShouldEmitVFEInfo || CheckResult) &&

           "Check result required but not created!");



    if (ShouldEmitCFICheck) {