Revert 289252 (and follow-up 289285), it caused PR31374

llvm-svn: 289713

14 files changed, 61 insertions, 212 deletions

diff --git a/clang/lib/AST/APValue.cpp b/clang/lib/AST/APValue.cpp
index 488ad3373ca..89231599727 100644
--- a/clang/lib/AST/APValue.cpp
+++ b/clang/lib/AST/APValue.cpp
@@ -27,7 +27,6 @@ namespace {
     CharUnits Offset;
     unsigned PathLength;
     unsigned CallIndex;
-    bool IsNullPtr;
   };
 }
 
@@ -150,11 +149,10 @@ APValue::APValue(const APValue &RHS) : Kind(Uninitialized) {
     MakeLValue();
     if (RHS.hasLValuePath())
       setLValue(RHS.getLValueBase(), RHS.getLValueOffset(), RHS.getLValuePath(),
-                RHS.isLValueOnePastTheEnd(), RHS.getLValueCallIndex(),
-                RHS.isNullPointer());
+                RHS.isLValueOnePastTheEnd(), RHS.getLValueCallIndex());
     else
       setLValue(RHS.getLValueBase(), RHS.getLValueOffset(), NoLValuePath(),
-                RHS.getLValueCallIndex(), RHS.isNullPointer());
+                RHS.getLValueCallIndex());
     break;
   case Array:
     MakeArray(RHS.getArrayInitializedElts(), RHS.getArraySize());
@@ -581,13 +579,8 @@ unsigned APValue::getLValueCallIndex() const {
   return ((const LV*)(const char*)Data.buffer)->CallIndex;
 }
 
-bool APValue::isNullPointer() const {
-  assert(isLValue() && "Invalid usage");
-  return ((const LV*)(const char*)Data.buffer)->IsNullPtr;
-}
-
 void APValue::setLValue(LValueBase B, const CharUnits &O, NoLValuePath,
-                        unsigned CallIndex, bool IsNullPtr) {
+                        unsigned CallIndex) {
   assert(isLValue() && "Invalid accessor");
   LV &LVal = *((LV*)(char*)Data.buffer);
   LVal.BaseAndIsOnePastTheEnd.setPointer(B);
@@ -595,12 +588,11 @@ void APValue::setLValue(LValueBase B, const CharUnits &O, NoLValuePath,
   LVal.Offset = O;
   LVal.CallIndex = CallIndex;
   LVal.resizePath((unsigned)-1);
-  LVal.IsNullPtr = IsNullPtr;
 }
 
 void APValue::setLValue(LValueBase B, const CharUnits &O,
                         ArrayRef<LValuePathEntry> Path, bool IsOnePastTheEnd,
-                        unsigned CallIndex, bool IsNullPtr) {
+                        unsigned CallIndex) {
   assert(isLValue() && "Invalid accessor");
   LV &LVal = *((LV*)(char*)Data.buffer);
   LVal.BaseAndIsOnePastTheEnd.setPointer(B);
@@ -609,7 +601,6 @@ void APValue::setLValue(LValueBase B, const CharUnits &O,
   LVal.CallIndex = CallIndex;
   LVal.resizePath(Path.size());
   memcpy(LVal.getPath(), Path.data(), Path.size() * sizeof(LValuePathEntry));
-  LVal.IsNullPtr = IsNullPtr;
 }
 
 const ValueDecl *APValue::getMemberPointerDecl() const {
diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index a4861d982e3..22be71a7272 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -9426,16 +9426,6 @@ ASTContext::ObjCMethodsAreEqual(const ObjCMethodDecl *MethodDecl,
   
 }
 
-uint64_t ASTContext::getTargetNullPointerValue(QualType QT) const {
-  unsigned AS;
-  if (QT->getUnqualifiedDesugaredType()->isNullPtrType())
-    AS = 0;
-  else
-    AS = QT->getPointeeType().getAddressSpace();
-
-  return getTargetInfo().getNullPointerValue(AS);
-}
-
 // Explicitly instantiate this in case a Redeclarable<T> is used from a TU that
 // doesn't include ASTContext.h
 template
diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index c57b7826320..5dd493cfff5 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -1088,7 +1088,6 @@ namespace {
     unsigned InvalidBase : 1;
     unsigned CallIndex : 31;
     SubobjectDesignator Designator;
-    bool IsNullPtr;
 
     const APValue::LValueBase getLValueBase() const { return Base; }
     CharUnits &getLValueOffset() { return Offset; }
@@ -1096,15 +1095,13 @@ namespace {
     unsigned getLValueCallIndex() const { return CallIndex; }
     SubobjectDesignator &getLValueDesignator() { return Designator; }
     const SubobjectDesignator &getLValueDesignator() const { return Designator;}
-    bool isNullPointer() const { return IsNullPtr;}
 
     void moveInto(APValue &V) const {
       if (Designator.Invalid)
-        V = APValue(Base, Offset, APValue::NoLValuePath(), CallIndex,
-                    IsNullPtr);
+        V = APValue(Base, Offset, APValue::NoLValuePath(), CallIndex);
       else
         V = APValue(Base, Offset, Designator.Entries,
-                    Designator.IsOnePastTheEnd, CallIndex, IsNullPtr);
+                    Designator.IsOnePastTheEnd, CallIndex);
     }
     void setFrom(ASTContext &Ctx, const APValue &V) {
       assert(V.isLValue());
@@ -1113,17 +1110,14 @@ namespace {
       InvalidBase = false;
       CallIndex = V.getLValueCallIndex();
       Designator = SubobjectDesignator(Ctx, V);
-      IsNullPtr = V.isNullPointer();
     }
 
-    void set(APValue::LValueBase B, unsigned I = 0, bool BInvalid = false,
-             bool IsNullPtr_ = false, uint64_t Offset_ = 0) {
+    void set(APValue::LValueBase B, unsigned I = 0, bool BInvalid = false) {
       Base = B;
-      Offset = CharUnits::fromQuantity(Offset_);
+      Offset = CharUnits::Zero();
       InvalidBase = BInvalid;
       CallIndex = I;
       Designator = SubobjectDesignator(getType(B));
-      IsNullPtr = IsNullPtr_;
     }
 
     void setInvalid(APValue::LValueBase B, unsigned I = 0) {
@@ -1136,7 +1130,7 @@ namespace {
                           CheckSubobjectKind CSK) {
       if (Designator.Invalid)
         return false;
-      if (IsNullPtr) {
+      if (!Base) {
         Info.CCEDiag(E, diag::note_constexpr_null_subobject)
           << CSK;
         Designator.setInvalid();
@@ -1165,22 +1159,9 @@ namespace {
       if (checkSubobject(Info, E, Imag ? CSK_Imag : CSK_Real))
         Designator.addComplexUnchecked(EltTy, Imag);
     }
-    void clearIsNullPointer() {
-      IsNullPtr = false;
-    }
-    void adjustOffsetAndIndex(EvalInfo &Info, const Expr *E, uint64_t Index,
-                              CharUnits ElementSize) {
-      // Compute the new offset in the appropriate width.
-      Offset += Index * ElementSize;
-      if (Index && checkNullPointer(Info, E, CSK_ArrayIndex))
-        Designator.adjustIndex(Info, E, Index);
-      if (Index)
-        clearIsNullPointer();
-    }
-    void adjustOffset(CharUnits N) {
-      Offset += N;
-      if (N.getQuantity())
-        clearIsNullPointer();
+    void adjustIndex(EvalInfo &Info, const Expr *E, uint64_t N) {
+      if (N && checkNullPointer(Info, E, CSK_ArrayIndex))
+        Designator.adjustIndex(Info, E, N);
     }
   };
 
@@ -2055,7 +2036,7 @@ static bool HandleLValueMember(EvalInfo &Info, const Expr *E, LValue &LVal,
   }
 
   unsigned I = FD->getFieldIndex();
-  LVal.adjustOffset(Info.Ctx.toCharUnitsFromBits(RL->getFieldOffset(I)));
+  LVal.Offset += Info.Ctx.toCharUnitsFromBits(RL->getFieldOffset(I));
   LVal.addDecl(Info, E, FD);
   return true;
 }
@@ -2109,7 +2090,9 @@ static bool HandleLValueArrayAdjustment(EvalInfo &Info, const Expr *E,
   if (!HandleSizeof(Info, E->getExprLoc(), EltTy, SizeOfPointee))
     return false;
 
-  LVal.adjustOffsetAndIndex(Info, E, Adjustment, SizeOfPointee);
+  // Compute the new offset in the appropriate width.
+  LVal.Offset += Adjustment * SizeOfPointee;
+  LVal.adjustIndex(Info, E, Adjustment);
   return true;
 }
 
@@ -5095,9 +5078,7 @@ public:
     return true;
   }
   bool ZeroInitialization(const Expr *E) {
-    auto Offset = Info.Ctx.getTargetNullPointerValue(E->getType());
-    Result.set((Expr*)nullptr, 0, false, true, Offset);
-    return true;
+    return Success((Expr*)nullptr);
   }
 
   bool VisitBinaryOperator(const BinaryOperator *E);
@@ -5196,8 +5177,6 @@ bool PointerExprEvaluator::VisitCastExpr(const CastExpr* E) {
       else
         CCEDiag(E, diag::note_constexpr_invalid_cast) << 2;
     }
-    if (E->getCastKind() == CK_AddressSpaceConversion && Result.IsNullPtr)
-      ZeroInitialization(E);
     return true;
 
   case CK_DerivedToBase:
@@ -5239,7 +5218,6 @@ bool PointerExprEvaluator::VisitCastExpr(const CastExpr* E) {
       Result.Offset = CharUnits::fromQuantity(N);
       Result.CallIndex = 0;
       Result.Designator.setInvalid();
-      Result.IsNullPtr = false;
       return true;
     } else {
       // Cast is of an lvalue, no need to change value.
@@ -8414,13 +8392,8 @@ bool IntExprEvaluator::VisitCastExpr(const CastExpr *E) {
       return true;
     }
 
-    uint64_t V;
-    if (LV.isNullPointer())
-      V = Info.Ctx.getTargetNullPointerValue(SrcType);
-    else
-      V = LV.getLValueOffset().getQuantity();
-
-    APSInt AsInt = Info.Ctx.MakeIntValue(V, SrcType);
+    APSInt AsInt = Info.Ctx.MakeIntValue(LV.getLValueOffset().getQuantity(), 
+                                         SrcType);
     return Success(HandleIntToIntCast(Info, E, DestType, SrcType, AsInt), E);
   }
 
diff --git a/clang/lib/Basic/Targets.cpp b/clang/lib/Basic/Targets.cpp
index ee84089835b..91eabb36bd3 100644
--- a/clang/lib/Basic/Targets.cpp
+++ b/clang/lib/Basic/Targets.cpp
@@ -2245,13 +2245,6 @@ public:
         return CCCR_OK;
     }
   }
-
-  // In amdgcn target the null pointer in global, constant, and generic
-  // address space has value 0 but in private and local address space has
-  // value ~0.
-  uint64_t getNullPointerValue(unsigned AS) const override {
-    return AS != LangAS::opencl_local && AS != 0 ? 0 : ~0;
-  }
 };
 
 const Builtin::Info AMDGPUTargetInfo::BuiltinInfo[] = {
diff --git a/clang/lib/CodeGen/CGDecl.cpp b/clang/lib/CodeGen/CGDecl.cpp
index 46573477580..695e92ea1d0 100644
--- a/clang/lib/CodeGen/CGDecl.cpp
+++ b/clang/lib/CodeGen/CGDecl.cpp
@@ -708,7 +708,7 @@ void CodeGenFunction::EmitScalarInit(const Expr *init, const ValueDecl *D,
     }
 
     auto ty = cast<llvm::PointerType>(tempLV.getAddress().getElementType());
-    llvm::Value *zero = CGM.getNullPointer(ty, tempLV.getType());
+    llvm::Value *zero = llvm::ConstantPointerNull::get(ty);
 
     // If __weak, we want to use a barrier under certain conditions.
     if (lifetime == Qualifiers::OCL_Weak)
diff --git a/clang/lib/CodeGen/CGExprAgg.cpp b/clang/lib/CodeGen/CGExprAgg.cpp
index 35148bea001..e24a0853c80 100644
--- a/clang/lib/CodeGen/CGExprAgg.cpp
+++ b/clang/lib/CodeGen/CGExprAgg.cpp
@@ -1052,8 +1052,7 @@ static bool isSimpleZero(const Expr *E, CodeGenFunction &CGF) {
     return true;
   // (int*)0 - Null pointer expressions.
   if (const CastExpr *ICE = dyn_cast<CastExpr>(E))
-    return ICE->getCastKind() == CK_NullToPointer &&
-        CGF.getTypes().isPointerZeroInitializable(E->getType());
+    return ICE->getCastKind() == CK_NullToPointer;
   // '\0'
   if (const CharacterLiteral *CL = dyn_cast<CharacterLiteral>(E))
     return CL->getValue() == 0;
diff --git a/clang/lib/CodeGen/CGExprConstant.cpp b/clang/lib/CodeGen/CGExprConstant.cpp
index 752f419f64e..345e0a9216a 100644
--- a/clang/lib/CodeGen/CGExprConstant.cpp
+++ b/clang/lib/CodeGen/CGExprConstant.cpp
@@ -16,7 +16,6 @@
 #include "CGObjCRuntime.h"
 #include "CGRecordLayout.h"
 #include "CodeGenModule.h"
-#include "TargetInfo.h"
 #include "clang/AST/APValue.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/RecordLayout.h"
@@ -1263,10 +1262,6 @@ llvm::Constant *CodeGenModule::EmitConstantExpr(const Expr *E,
   return C;
 }
 
-llvm::Constant *CodeGenModule::getNullPointer(llvm::PointerType *T, QualType QT) {
-  return getTargetCodeGenInfo().getNullPointer(*this, T, QT);
-}
-
 llvm::Constant *CodeGenModule::EmitConstantValue(const APValue &Value,
                                                  QualType DestType,
                                                  CodeGenFunction *CGF) {
@@ -1298,7 +1293,6 @@ llvm::Constant *CodeGenModule::EmitConstantValue(const APValue &Value,
       llvm::ConstantInt::get(Int64Ty, Value.getLValueOffset().getQuantity());
 
     llvm::Constant *C = nullptr;
-
     if (APValue::LValueBase LVBase = Value.getLValueBase()) {
       // An array can be represented as an lvalue referring to the base.
       if (isa<llvm::ArrayType>(DestTy)) {
@@ -1329,9 +1323,7 @@ llvm::Constant *CodeGenModule::EmitConstantValue(const APValue &Value,
 
       // Convert to the appropriate type; this could be an lvalue for
       // an integer.
-      if (auto PT = dyn_cast<llvm::PointerType>(DestTy)) {
-        if (Value.isNullPointer())
-          return getNullPointer(PT, DestType);
+      if (isa<llvm::PointerType>(DestTy)) {
         // Convert the integer to a pointer-sized integer before converting it
         // to a pointer.
         C = llvm::ConstantExpr::getIntegerCast(
@@ -1518,7 +1510,7 @@ static llvm::Constant *EmitNullConstantForBase(CodeGenModule &CGM,
                                                const CXXRecordDecl *base);
 
 static llvm::Constant *EmitNullConstant(CodeGenModule &CGM,
-                                        const RecordDecl *record,
+                                        const CXXRecordDecl *record,
                                         bool asCompleteObject) {
   const CGRecordLayout &layout = CGM.getTypes().getCGRecordLayout(record);
   llvm::StructType *structure =
@@ -1528,29 +1520,25 @@ static llvm::Constant *EmitNullConstant(CodeGenModule &CGM,
   unsigned numElements = structure->getNumElements();
   std::vector<llvm::Constant *> elements(numElements);
 
-  auto CXXR = dyn_cast<CXXRecordDecl>(record);
   // Fill in all the bases.
-  if (CXXR) {
-    for (const auto &I : CXXR->bases()) {
-      if (I.isVirtual()) {
-        // Ignore virtual bases; if we're laying out for a complete
-        // object, we'll lay these out later.
-        continue;
-      }
+  for (const auto &I : record->bases()) {
+    if (I.isVirtual()) {
+      // Ignore virtual bases; if we're laying out for a complete
+      // object, we'll lay these out later.
+      continue;
+    }
 
-      const CXXRecordDecl *base =
-        cast<CXXRecordDecl>(I.getType()->castAs<RecordType>()->getDecl());
+    const CXXRecordDecl *base = 
+      cast<CXXRecordDecl>(I.getType()->castAs<RecordType>()->getDecl());
 
-      // Ignore empty bases.
-      if (base->isEmpty() ||
-          CGM.getContext().getASTRecordLayout(base).getNonVirtualSize()
-              .isZero())
-        continue;
-
-      unsigned fieldIndex = layout.getNonVirtualBaseLLVMFieldNo(base);
-      llvm::Type *baseType = structure->getElementType(fieldIndex);
-      elements[fieldIndex] = EmitNullConstantForBase(CGM, baseType, base);
-    }
+    // Ignore empty bases.
+    if (base->isEmpty() ||
+        CGM.getContext().getASTRecordLayout(base).getNonVirtualSize().isZero())
+      continue;
+    
+    unsigned fieldIndex = layout.getNonVirtualBaseLLVMFieldNo(base);
+    llvm::Type *baseType = structure->getElementType(fieldIndex);
+    elements[fieldIndex] = EmitNullConstantForBase(CGM, baseType, base);
   }
 
   // Fill in all the fields.
@@ -1574,8 +1562,8 @@ static llvm::Constant *EmitNullConstant(CodeGenModule &CGM,
   }
 
   // Fill in the virtual bases, if we're working with the complete object.
-  if (CXXR && asCompleteObject) {
-    for (const auto &I : CXXR->vbases()) {
+  if (asCompleteObject) {
+    for (const auto &I : record->vbases()) {
       const CXXRecordDecl *base = 
         cast<CXXRecordDecl>(I.getType()->castAs<RecordType>()->getDecl());
 
@@ -1617,10 +1605,6 @@ static llvm::Constant *EmitNullConstantForBase(CodeGenModule &CGM,
 }
 
 llvm::Constant *CodeGenModule::EmitNullConstant(QualType T) {
-  if (T->getAs<PointerType>())
-    return getNullPointer(
-        cast<llvm::PointerType>(getTypes().ConvertTypeForMem(T)), T);
-
   if (getTypes().isZeroInitializable(T))
     return llvm::Constant::getNullValue(getTypes().ConvertTypeForMem(T));
     
@@ -1636,8 +1620,10 @@ llvm::Constant *CodeGenModule::EmitNullConstant(QualType T) {
     return llvm::ConstantArray::get(ATy, Array);
   }
 
-  if (const RecordType *RT = T->getAs<RecordType>())
-    return ::EmitNullConstant(*this, RT->getDecl(), /*complete object*/ true);
+  if (const RecordType *RT = T->getAs<RecordType>()) {
+    const CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
+    return ::EmitNullConstant(*this, RD, /*complete object*/ true);
+  }
 
   assert(T->isMemberDataPointerType() &&
          "Should only see pointers to data members here!");
diff --git a/clang/lib/CodeGen/CGExprScalar.cpp b/clang/lib/CodeGen/CGExprScalar.cpp
index e9bdbda34aa..e763e6ab020 100644
--- a/clang/lib/CodeGen/CGExprScalar.cpp
+++ b/clang/lib/CodeGen/CGExprScalar.cpp
@@ -19,7 +19,6 @@
 #include "TargetInfo.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/DeclObjC.h"
-#include "clang/AST/Expr.h"
 #include "clang/AST/RecordLayout.h"
 #include "clang/AST/StmtVisitor.h"
 #include "clang/Basic/TargetInfo.h"
@@ -172,9 +171,9 @@ public:
   }
 
   /// EmitPointerToBoolConversion - Perform a pointer to boolean conversion.
-  Value *EmitPointerToBoolConversion(Value *V, QualType QT) {
-    Value *Zero = CGF.CGM.getNullPointer(cast<llvm::PointerType>(V->getType()), QT);
-
+  Value *EmitPointerToBoolConversion(Value *V) {
+    Value *Zero = llvm::ConstantPointerNull::get(
+                                      cast<llvm::PointerType>(V->getType()));
     return Builder.CreateICmpNE(V, Zero, "tobool");
   }
 
@@ -598,7 +597,7 @@ Value *ScalarExprEmitter::EmitConversionToBool(Value *Src, QualType SrcType) {
     return EmitIntToBoolConversion(Src);
 
   assert(isa<llvm::PointerType>(Src->getType()));
-  return EmitPointerToBoolConversion(Src, SrcType);
+  return EmitPointerToBoolConversion(Src);
 }
 
 void ScalarExprEmitter::EmitFloatConversionCheck(
@@ -1401,23 +1400,11 @@ Value *ScalarExprEmitter::VisitCastExpr(CastExpr *CE) {
     return Builder.CreateBitCast(Src, DstTy);
   }
   case CK_AddressSpaceConversion: {
-    Expr::EvalResult Result;
-    if (E->EvaluateAsRValue(Result, CGF.getContext()) &&
-        Result.Val.isNullPointer()) {
-      // If E has side effect, it is emitted even if its final result is a
-      // null pointer. In that case, a DCE pass should be able to
-      // eliminate the useless instructions emitted during translating E.
-      if (Result.HasSideEffects)
-        Visit(E);
-      return CGF.CGM.getNullPointer(cast<llvm::PointerType>(
-          ConvertType(DestTy)), DestTy);
-    }
+    Value *Src = Visit(const_cast<Expr*>(E));
     // Since target may map different address spaces in AST to the same address
     // space, an address space conversion may end up as a bitcast.
-    auto *Src = Visit(E);
-    return CGF.CGM.getTargetCodeGenInfo().performAddrSpaceCast(CGF, Src,
-                                                               E->getType(),
-                                                               DestTy);
+    return Builder.CreatePointerBitCastOrAddrSpaceCast(Src,
+                                                       ConvertType(DestTy));
   }
   case CK_AtomicToNonAtomic:
   case CK_NonAtomicToAtomic:
@@ -1472,8 +1459,8 @@ Value *ScalarExprEmitter::VisitCastExpr(CastExpr *CE) {
     if (MustVisitNullValue(E))
       (void) Visit(E);
 
-    return CGF.CGM.getNullPointer(cast<llvm::PointerType>(ConvertType(DestTy)),
-                              DestTy);
+    return llvm::ConstantPointerNull::get(
+                               cast<llvm::PointerType>(ConvertType(DestTy)));
 
   case CK_NullToMemberPointer: {
     if (MustVisitNullValue(E))
@@ -1566,7 +1553,7 @@ Value *ScalarExprEmitter::VisitCastExpr(CastExpr *CE) {
   case CK_IntegralToBoolean:
     return EmitIntToBoolConversion(Visit(E));
   case CK_PointerToBoolean:
-    return EmitPointerToBoolConversion(Visit(E), E->getType());
+    return EmitPointerToBoolConversion(Visit(E));
   case CK_FloatingToBoolean:
     return EmitFloatToBoolConversion(Visit(E));
   case CK_MemberPointerToBoolean: {
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 98b6215d0b4..78f43bdef99 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -2611,16 +2611,9 @@ void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D,
   else
     GV->setDLLStorageClass(llvm::GlobalVariable::DefaultStorageClass);
 
-  if (Linkage == llvm::GlobalVariable::CommonLinkage) {
+  if (Linkage == llvm::GlobalVariable::CommonLinkage)
     // common vars aren't constant even if declared const.
     GV->setConstant(false);
-    // Tentative definition of global variables may be initialized with
-    // non-zero null pointers. In this case they should have weak linkage
-    // since common linkage must have zero initializer and must not have
-    // explicit section therefore cannot have non-zero initial value.
-    if (!GV->getInitializer()->isNullValue())
-      GV->setLinkage(llvm::GlobalVariable::WeakAnyLinkage);
-  }
 
   setNonAliasAttributes(D, GV);
 
diff --git a/clang/lib/CodeGen/CodeGenModule.h b/clang/lib/CodeGen/CodeGenModule.h
index f014be95570..be45bb8ea44 100644
--- a/clang/lib/CodeGen/CodeGenModule.h
+++ b/clang/lib/CodeGen/CodeGenModule.h
@@ -1155,11 +1155,6 @@ public:
   llvm::Value *
   createOpenCLIntToSamplerConversion(const Expr *E, CodeGenFunction &CGF);
 
-  /// Get target specific null pointer.
-  /// \param T is the LLVM type of the null pointer.
-  /// \param QT is the clang QualType of the null pointer.
-  llvm::Constant *getNullPointer(llvm::PointerType *T, QualType QT);
-
 private:
   llvm::Constant *
   GetOrCreateLLVMFunction(StringRef MangledName, llvm::Type *Ty, GlobalDecl D,
diff --git a/clang/lib/CodeGen/CodeGenTypes.cpp b/clang/lib/CodeGen/CodeGenTypes.cpp
index 357bff27a31..c92095bbbe6 100644
--- a/clang/lib/CodeGen/CodeGenTypes.cpp
+++ b/clang/lib/CodeGen/CodeGenTypes.cpp
@@ -736,14 +736,10 @@ CodeGenTypes::getCGRecordLayout(const RecordDecl *RD) {
   return *Layout;
 }
 
-bool CodeGenTypes::isPointerZeroInitializable(QualType T) {
-  assert (T->getAs<PointerType>() && "Invalid type");
-  return isZeroInitializable(T);
-}
-
 bool CodeGenTypes::isZeroInitializable(QualType T) {
-  if (T->getAs<PointerType>())
-    return Context.getTargetNullPointerValue(T) == 0;
+  // No need to check for member pointers when not compiling C++.
+  if (!Context.getLangOpts().CPlusPlus)
+    return true;
 
   if (const auto *AT = Context.getAsArrayType(T)) {
     if (isa<IncompleteArrayType>(AT))
@@ -757,7 +753,7 @@ bool CodeGenTypes::isZeroInitializable(QualType T) {
   // Records are non-zero-initializable if they contain any
   // non-zero-initializable subobjects.
   if (const RecordType *RT = T->getAs<RecordType>()) {
-    auto RD = cast<RecordDecl>(RT->getDecl());
+    const CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
     return isZeroInitializable(RD);
   }
 
diff --git a/clang/lib/CodeGen/CodeGenTypes.h b/clang/lib/CodeGen/CodeGenTypes.h
index 2ce6591e4eb..00df10dd138 100644
--- a/clang/lib/CodeGen/CodeGenTypes.h
+++ b/clang/lib/CodeGen/CodeGenTypes.h
@@ -352,10 +352,6 @@ public:  // These are internal details of CGT that shouldn't be used externally.
   /// zero-initialized (in the C++ sense) with an LLVM zeroinitializer.
   bool isZeroInitializable(QualType T);
 
-  /// Check if the pointer type can be zero-initialized (in the C++ sense)
-  /// with an LLVM zeroinitializer.
-  bool isPointerZeroInitializable(QualType T);
-
   /// IsZeroInitializable - Return whether a record type can be
   /// zero-initialized (in the C++ sense) with an LLVM zeroinitializer.
   bool isZeroInitializable(const RecordDecl *RD);
diff --git a/clang/lib/CodeGen/TargetInfo.cpp b/clang/lib/CodeGen/TargetInfo.cpp
index 391eb53d250..38b164b113a 100644
--- a/clang/lib/CodeGen/TargetInfo.cpp
+++ b/clang/lib/CodeGen/TargetInfo.cpp
@@ -401,20 +401,6 @@ unsigned TargetCodeGenInfo::getOpenCLKernelCallingConv() const {
   return llvm::CallingConv::C;
 }
 
-llvm::Constant *TargetCodeGenInfo::getNullPointer(const CodeGen::CodeGenModule &CGM,
-    llvm::PointerType *T, QualType QT) const {
-  return llvm::ConstantPointerNull::get(T);
-}
-
-llvm::Value *TargetCodeGenInfo::performAddrSpaceCast(
-    CodeGen::CodeGenFunction &CGF, llvm::Value *Src, QualType SrcTy,
-    QualType DestTy) const {
-  // Since target may map different address spaces in AST to the same address
-  // space, an address space conversion may end up as a bitcast.
-  return CGF.Builder.CreatePointerBitCastOrAddrSpaceCast(Src,
-             CGF.ConvertType(DestTy));
-}
-
 static bool isEmptyRecord(ASTContext &Context, QualType T, bool AllowArrays);
 
 /// isEmptyField - Return true iff a the field is "empty", that is it
@@ -7089,10 +7075,8 @@ public:
   void setTargetAttributes(const Decl *D, llvm::GlobalValue *GV,
                            CodeGen::CodeGenModule &M) const override;
   unsigned getOpenCLKernelCallingConv() const override;
-
-  llvm::Constant *getNullPointer(const CodeGen::CodeGenModule &CGM,
-      llvm::PointerType *T, QualType QT) const override;
 };
+
 }
 
 static void appendOpenCLVersionMD (CodeGen::CodeGenModule &CGM);
@@ -7156,24 +7140,6 @@ unsigned AMDGPUTargetCodeGenInfo::getOpenCLKernelCallingConv() const {
   return llvm::CallingConv::AMDGPU_KERNEL;
 }
 
-// Currently LLVM assumes null pointers always have value 0,
-// which results in incorrectly transformed IR. Therefore, instead of
-// emitting null pointers in private and local address spaces, a null
-// pointer in generic address space is emitted which is casted to a
-// pointer in local or private address space.
-llvm::Constant *AMDGPUTargetCodeGenInfo::getNullPointer(
-    const CodeGen::CodeGenModule &CGM, llvm::PointerType *PT,
-    QualType QT) const {
-  if (CGM.getContext().getTargetNullPointerValue(QT) == 0)
-    return llvm::ConstantPointerNull::get(PT);
-
-  auto &Ctx = CGM.getContext();
-  auto NPT = llvm::PointerType::get(PT->getElementType(),
-      Ctx.getTargetAddressSpace(LangAS::opencl_generic));
-  return llvm::ConstantExpr::getAddrSpaceCast(
-      llvm::ConstantPointerNull::get(NPT), PT);
-}
-
 //===----------------------------------------------------------------------===//
 // SPARC v8 ABI Implementation.
 // Based on the SPARC Compliance Definition version 2.4.1.
diff --git a/clang/lib/CodeGen/TargetInfo.h b/clang/lib/CodeGen/TargetInfo.h
index 223d6d047af..e46382596af 100644
--- a/clang/lib/CodeGen/TargetInfo.h
+++ b/clang/lib/CodeGen/TargetInfo.h
@@ -220,22 +220,6 @@ public:
 
   /// Get LLVM calling convention for OpenCL kernel.
   virtual unsigned getOpenCLKernelCallingConv() const;
-
-  /// Get target specific null pointer.
-  /// \param T is the LLVM type of the null pointer.
-  /// \param QT is the clang QualType of the null pointer.
-  /// \return ConstantPointerNull with the given type \p T.
-  /// Each target can override it to return its own desired constant value.
-  virtual llvm::Constant *getNullPointer(const CodeGen::CodeGenModule &CGM,
-      llvm::PointerType *T, QualType QT) const;
-
-  /// Perform address space cast of an expression of pointer type.
-  /// \param V is the LLVM value to be casted to another address space.
-  /// \param SrcTy is the QualType of \p V.
-  /// \param DestTy is the destination QualType.
-  virtual llvm::Value *performAddrSpaceCast(CodeGen::CodeGenFunction &CGF,
-      llvm::Value *V, QualType SrcTy, QualType DestTy) const;
-
 };
 
 } // namespace CodeGen