diff --git a/clang-tools-extra/clang-tidy/fuchsia/MultipleInheritanceCheck.cpp b/clang-tools-extra/clang-tidy/fuchsia/MultipleInheritanceCheck.cpp
index 8aecd3ba27b2e..b5ce23ae8feda 100644
--- a/clang-tools-extra/clang-tidy/fuchsia/MultipleInheritanceCheck.cpp
+++ b/clang-tools-extra/clang-tidy/fuchsia/MultipleInheritanceCheck.cpp
@@ -53,7 +53,7 @@ bool MultipleInheritanceCheck::isCurrentClassInterface(
 
   // Interfaces should have exclusively pure methods.
   return llvm::none_of(Node->methods(), [](const CXXMethodDecl *M) {
-    return M->isUserProvided() && !M->isPure() && !M->isStatic();
+    return M->isUserProvided() && !M->isPureVirtual() && !M->isStatic();
   });
 }
 
@@ -103,8 +103,8 @@ void MultipleInheritanceCheck::check(const MatchFinder::MatchResult &Result) {
       const auto *Base = cast<CXXRecordDecl>(Ty->getDecl()->getDefinition());
       if (!isInterface(Base)) NumConcrete++;
     }
-    
-    // Check virtual bases to see if there is more than one concrete 
+
+    // Check virtual bases to see if there is more than one concrete
     // non-virtual base.
     for (const auto &V : D->vbases()) {
       const auto *Ty = V.getType()->getAs<RecordType>();
diff --git a/clang-tools-extra/clang-tidy/modernize/UseEqualsDeleteCheck.cpp b/clang-tools-extra/clang-tidy/modernize/UseEqualsDeleteCheck.cpp
index 059a0af60d3ee..9561cc71183d9 100644
--- a/clang-tools-extra/clang-tidy/modernize/UseEqualsDeleteCheck.cpp
+++ b/clang-tools-extra/clang-tidy/modernize/UseEqualsDeleteCheck.cpp
@@ -17,11 +17,12 @@ namespace clang::tidy::modernize {
 
 namespace {
 AST_MATCHER(FunctionDecl, hasAnyDefinition) {
-  if (Node.hasBody() || Node.isPure() || Node.isDefaulted() || Node.isDeleted())
+  if (Node.hasBody() || Node.isPureVirtual() || Node.isDefaulted() ||
+      Node.isDeleted())
     return true;
 
   if (const FunctionDecl *Definition = Node.getDefinition())
-    if (Definition->hasBody() || Definition->isPure() ||
+    if (Definition->hasBody() || Definition->isPureVirtual() ||
         Definition->isDefaulted() || Definition->isDeleted())
       return true;
 
diff --git a/clang-tools-extra/clangd/SemanticHighlighting.cpp b/clang-tools-extra/clangd/SemanticHighlighting.cpp
index 37939d36425a9..ee3772e3d380c 100644
--- a/clang-tools-extra/clangd/SemanticHighlighting.cpp
+++ b/clang-tools-extra/clangd/SemanticHighlighting.cpp
@@ -265,7 +265,7 @@ bool isStatic(const Decl *D) {
 
 bool isAbstract(const Decl *D) {
   if (const auto *CMD = llvm::dyn_cast<CXXMethodDecl>(D))
-    return CMD->isPure();
+    return CMD->isPureVirtual();
   if (const auto *CRD = llvm::dyn_cast<CXXRecordDecl>(D))
     return CRD->hasDefinition() && CRD->isAbstract();
   return false;
diff --git a/clang-tools-extra/clangd/XRefs.cpp b/clang-tools-extra/clangd/XRefs.cpp
index 5f41f788a6939..250d571eea191 100644
--- a/clang-tools-extra/clangd/XRefs.cpp
+++ b/clang-tools-extra/clangd/XRefs.cpp
@@ -427,7 +427,7 @@ locateASTReferent(SourceLocation CurLoc, const syntax::Token *TouchedIdentifier,
       // Special case: virtual void ^method() = 0: jump to all overrides.
       // FIXME: extend it to ^virtual, unfortunately, virtual location is not
       // saved in the AST.
-      if (CMD->isPure()) {
+      if (CMD->isPureVirtual()) {
         if (TouchedIdentifier && SM.getSpellingLoc(CMD->getLocation()) ==
                                      TouchedIdentifier->location()) {
           VirtualMethods.insert(getSymbolID(CMD));
diff --git a/clang/include/clang/AST/Decl.h b/clang/include/clang/AST/Decl.h
index 98af552d400f3..f26fb5ad5f133 100644
--- a/clang/include/clang/AST/Decl.h
+++ b/clang/include/clang/AST/Decl.h
@@ -2294,8 +2294,8 @@ class FunctionDecl : public DeclaratorDecl,
 
   /// Whether this virtual function is pure, i.e. makes the containing class
   /// abstract.
-  bool isPure() const { return FunctionDeclBits.IsPure; }
-  void setPure(bool P = true);
+  bool isPureVirtual() const { return FunctionDeclBits.IsPureVirtual; }
+  void setIsPureVirtual(bool P = true);
 
   /// Whether this templated function will be late parsed.
   bool isLateTemplateParsed() const {
diff --git a/clang/include/clang/AST/DeclBase.h b/clang/include/clang/AST/DeclBase.h
index d957ea24f6394..9a4736019d1b1 100644
--- a/clang/include/clang/AST/DeclBase.h
+++ b/clang/include/clang/AST/DeclBase.h
@@ -1708,7 +1708,7 @@ class DeclContext {
     LLVM_PREFERRED_TYPE(bool)
     uint64_t IsVirtualAsWritten : 1;
     LLVM_PREFERRED_TYPE(bool)
-    uint64_t IsPure : 1;
+    uint64_t IsPureVirtual : 1;
     LLVM_PREFERRED_TYPE(bool)
     uint64_t HasInheritedPrototype : 1;
     LLVM_PREFERRED_TYPE(bool)
diff --git a/clang/include/clang/AST/DeclCXX.h b/clang/include/clang/AST/DeclCXX.h
index 75b73700c44d6..9cebaff63bb0d 100644
--- a/clang/include/clang/AST/DeclCXX.h
+++ b/clang/include/clang/AST/DeclCXX.h
@@ -266,7 +266,7 @@ class CXXRecordDecl : public RecordDecl {
   friend class LambdaExpr;
   friend class ODRDiagsEmitter;
 
-  friend void FunctionDecl::setPure(bool);
+  friend void FunctionDecl::setIsPureVirtual(bool);
   friend void TagDecl::startDefinition();
 
   /// Values used in DefinitionData fields to represent special members.
@@ -2110,7 +2110,7 @@ class CXXMethodDecl : public FunctionDecl {
 
     // Member function is virtual if it is marked explicitly so, or if it is
     // declared in __interface -- then it is automatically pure virtual.
-    if (CD->isVirtualAsWritten() || CD->isPure())
+    if (CD->isVirtualAsWritten() || CD->isPureVirtual())
       return true;
 
     return CD->size_overridden_methods() != 0;
diff --git a/clang/include/clang/ASTMatchers/ASTMatchers.h b/clang/include/clang/ASTMatchers/ASTMatchers.h
index 65196c52a3e29..dc1f49525a004 100644
--- a/clang/include/clang/ASTMatchers/ASTMatchers.h
+++ b/clang/include/clang/ASTMatchers/ASTMatchers.h
@@ -6351,9 +6351,7 @@ AST_POLYMORPHIC_MATCHER(isFinal,
 ///   };
 /// \endcode
 ///   matches A::x
-AST_MATCHER(CXXMethodDecl, isPure) {
-  return Node.isPure();
-}
+AST_MATCHER(CXXMethodDecl, isPure) { return Node.isPureVirtual(); }
 
 /// Matches if the given method declaration is const.
 ///
diff --git a/clang/lib/AST/ASTImporter.cpp b/clang/lib/AST/ASTImporter.cpp
index aa23c99b59901..b364796073022 100644
--- a/clang/lib/AST/ASTImporter.cpp
+++ b/clang/lib/AST/ASTImporter.cpp
@@ -3896,7 +3896,7 @@ ExpectedDecl ASTNodeImporter::VisitFunctionDecl(FunctionDecl *D) {
   ToFunction->setLexicalDeclContext(LexicalDC);
   ToFunction->setVirtualAsWritten(D->isVirtualAsWritten());
   ToFunction->setTrivial(D->isTrivial());
-  ToFunction->setPure(D->isPure());
+  ToFunction->setIsPureVirtual(D->isPureVirtual());
   ToFunction->setDefaulted(D->isDefaulted());
   ToFunction->setExplicitlyDefaulted(D->isExplicitlyDefaulted());
   ToFunction->setDeletedAsWritten(D->isDeletedAsWritten());
diff --git a/clang/lib/AST/ASTStructuralEquivalence.cpp b/clang/lib/AST/ASTStructuralEquivalence.cpp
index 5ec4a66879c02..5103fc86a8005 100644
--- a/clang/lib/AST/ASTStructuralEquivalence.cpp
+++ b/clang/lib/AST/ASTStructuralEquivalence.cpp
@@ -1467,7 +1467,7 @@ static bool IsStructurallyEquivalent(StructuralEquivalenceContext &Context,
       Method1->isConst() == Method2->isConst() &&
       Method1->isVolatile() == Method2->isVolatile() &&
       Method1->isVirtual() == Method2->isVirtual() &&
-      Method1->isPure() == Method2->isPure() &&
+      Method1->isPureVirtual() == Method2->isPureVirtual() &&
       Method1->isDefaulted() == Method2->isDefaulted() &&
       Method1->isDeleted() == Method2->isDeleted();
   if (!PropertiesEqual)
diff --git a/clang/lib/AST/Decl.cpp b/clang/lib/AST/Decl.cpp
index d373329d7272a..2c3a0afee8cef 100644
--- a/clang/lib/AST/Decl.cpp
+++ b/clang/lib/AST/Decl.cpp
@@ -3036,7 +3036,7 @@ FunctionDecl::FunctionDecl(Kind DK, ASTContext &C, DeclContext *DC,
   FunctionDeclBits.IsInline = isInlineSpecified;
   FunctionDeclBits.IsInlineSpecified = isInlineSpecified;
   FunctionDeclBits.IsVirtualAsWritten = false;
-  FunctionDeclBits.IsPure = false;
+  FunctionDeclBits.IsPureVirtual = false;
   FunctionDeclBits.HasInheritedPrototype = false;
   FunctionDeclBits.HasWrittenPrototype = true;
   FunctionDeclBits.IsDeleted = false;
@@ -3203,8 +3203,8 @@ void FunctionDecl::setBody(Stmt *B) {
     EndRangeLoc = B->getEndLoc();
 }
 
-void FunctionDecl::setPure(bool P) {
-  FunctionDeclBits.IsPure = P;
+void FunctionDecl::setIsPureVirtual(bool P) {
+  FunctionDeclBits.IsPureVirtual = P;
   if (P)
     if (auto *Parent = dyn_cast<CXXRecordDecl>(getDeclContext()))
       Parent->markedVirtualFunctionPure();
diff --git a/clang/lib/AST/DeclCXX.cpp b/clang/lib/AST/DeclCXX.cpp
index c11f6458c07dd..117e802dae2d9 100644
--- a/clang/lib/AST/DeclCXX.cpp
+++ b/clang/lib/AST/DeclCXX.cpp
@@ -2079,7 +2079,7 @@ void CXXRecordDecl::completeDefinition(CXXFinalOverriderMap *FinalOverriders) {
         //   A class is abstract if it contains or inherits at least one
         //   pure virtual function for which the final overrider is pure
         //   virtual.
-        if (SO->second.front().Method->isPure()) {
+        if (SO->second.front().Method->isPureVirtual()) {
           data().Abstract = true;
           Done = true;
           break;
@@ -2298,7 +2298,7 @@ CXXMethodDecl *CXXMethodDecl::getDevirtualizedMethod(const Expr *Base,
   // If the member function is marked 'final', we know that it can't be
   // overridden and can therefore devirtualize it unless it's pure virtual.
   if (hasAttr<FinalAttr>())
-    return isPure() ? nullptr : this;
+    return isPureVirtual() ? nullptr : this;
 
   // If Base is unknown, we cannot devirtualize.
   if (!Base)
@@ -2327,7 +2327,7 @@ CXXMethodDecl *CXXMethodDecl::getDevirtualizedMethod(const Expr *Base,
   // If that method is pure virtual, we can't devirtualize. If this code is
   // reached, the result would be UB, not a direct call to the derived class
   // function, and we can't assume the derived class function is defined.
-  if (DevirtualizedMethod->isPure())
+  if (DevirtualizedMethod->isPureVirtual())
     return nullptr;
 
   // If that method is marked final, we can devirtualize it.
diff --git a/clang/lib/AST/DeclPrinter.cpp b/clang/lib/AST/DeclPrinter.cpp
index 24da6f2ef32b4..822ac12c4c7dd 100644
--- a/clang/lib/AST/DeclPrinter.cpp
+++ b/clang/lib/AST/DeclPrinter.cpp
@@ -871,7 +871,7 @@ void DeclPrinter::VisitFunctionDecl(FunctionDecl *D) {
 
   prettyPrintAttributes(D, Out, AttrPrintLoc::Right);
 
-  if (D->isPure())
+  if (D->isPureVirtual())
     Out << " = 0";
   else if (D->isDeletedAsWritten())
     Out << " = delete";
diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index f20850d14c0c8..0884988c48b4e 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -5839,7 +5839,7 @@ static const CXXMethodDecl *HandleVirtualDispatch(
   // C++2a [class.abstract]p6:
   //   the effect of making a virtual call to a pure virtual function [...] is
   //   undefined
-  if (Callee->isPure()) {
+  if (Callee->isPureVirtual()) {
     Info.FFDiag(E, diag::note_constexpr_pure_virtual_call, 1) << Callee;
     Info.Note(Callee->getLocation(), diag::note_declared_at);
     return nullptr;
diff --git a/clang/lib/AST/Interp/Interp.cpp b/clang/lib/AST/Interp/Interp.cpp
index bdb86322df663..ac03837408a4d 100644
--- a/clang/lib/AST/Interp/Interp.cpp
+++ b/clang/lib/AST/Interp/Interp.cpp
@@ -490,7 +490,7 @@ bool CheckThis(InterpState &S, CodePtr OpPC, const Pointer &This) {
 }
 
 bool CheckPure(InterpState &S, CodePtr OpPC, const CXXMethodDecl *MD) {
-  if (!MD->isPure())
+  if (!MD->isPureVirtual())
     return true;
   const SourceInfo &E = S.Current->getSource(OpPC);
   S.FFDiag(E, diag::note_constexpr_pure_virtual_call, 1) << MD;
diff --git a/clang/lib/AST/JSONNodeDumper.cpp b/clang/lib/AST/JSONNodeDumper.cpp
index 637d06cee78c8..cb3d3b0df1ee3 100644
--- a/clang/lib/AST/JSONNodeDumper.cpp
+++ b/clang/lib/AST/JSONNodeDumper.cpp
@@ -930,7 +930,7 @@ void JSONNodeDumper::VisitFunctionDecl(const FunctionDecl *FD) {
     JOS.attribute("storageClass", VarDecl::getStorageClassSpecifierString(SC));
   attributeOnlyIfTrue("inline", FD->isInlineSpecified());
   attributeOnlyIfTrue("virtual", FD->isVirtualAsWritten());
-  attributeOnlyIfTrue("pure", FD->isPure());
+  attributeOnlyIfTrue("pure", FD->isPureVirtual());
   attributeOnlyIfTrue("explicitlyDeleted", FD->isDeletedAsWritten());
   attributeOnlyIfTrue("constexpr", FD->isConstexpr());
   attributeOnlyIfTrue("variadic", FD->isVariadic());
diff --git a/clang/lib/AST/ODRDiagsEmitter.cpp b/clang/lib/AST/ODRDiagsEmitter.cpp
index 9dcd2ed04f6f7..5b1cdc16e2ea2 100644
--- a/clang/lib/AST/ODRDiagsEmitter.cpp
+++ b/clang/lib/AST/ODRDiagsEmitter.cpp
@@ -1102,8 +1102,8 @@ bool ODRDiagsEmitter::diagnoseMismatch(
 
     const bool FirstVirtual = FirstMethod->isVirtualAsWritten();
     const bool SecondVirtual = SecondMethod->isVirtualAsWritten();
-    const bool FirstPure = FirstMethod->isPure();
-    const bool SecondPure = SecondMethod->isPure();
+    const bool FirstPure = FirstMethod->isPureVirtual();
+    const bool SecondPure = SecondMethod->isPureVirtual();
     if ((FirstVirtual || SecondVirtual) &&
         (FirstVirtual != SecondVirtual || FirstPure != SecondPure)) {
       DiagMethodError(MethodVirtual) << FirstPure << FirstVirtual;
diff --git a/clang/lib/AST/ODRHash.cpp b/clang/lib/AST/ODRHash.cpp
index 07677d655c5af..c5aa91a81da05 100644
--- a/clang/lib/AST/ODRHash.cpp
+++ b/clang/lib/AST/ODRHash.cpp
@@ -688,7 +688,7 @@ void ODRHash::AddFunctionDecl(const FunctionDecl *Function,
   ID.AddInteger(Function->getStorageClass());
   AddBoolean(Function->isInlineSpecified());
   AddBoolean(Function->isVirtualAsWritten());
-  AddBoolean(Function->isPure());
+  AddBoolean(Function->isPureVirtual());
   AddBoolean(Function->isDeletedAsWritten());
   AddBoolean(Function->isExplicitlyDefaulted());
 
diff --git a/clang/lib/AST/RecordLayoutBuilder.cpp b/clang/lib/AST/RecordLayoutBuilder.cpp
index 706991f4fb501..6dfaadd92e797 100644
--- a/clang/lib/AST/RecordLayoutBuilder.cpp
+++ b/clang/lib/AST/RecordLayoutBuilder.cpp
@@ -2349,7 +2349,7 @@ static const CXXMethodDecl *computeKeyFunction(ASTContext &Context,
     if (!MD->isVirtual())
       continue;
 
-    if (MD->isPure())
+    if (MD->isPureVirtual())
       continue;
 
     // Ignore implicit member functions, they are always marked as inline, but
@@ -3293,7 +3293,7 @@ void MicrosoftRecordLayoutBuilder::computeVtorDispSet(
   // Seed the working set with our non-destructor, non-pure virtual methods.
   for (const CXXMethodDecl *MD : RD->methods())
     if (MicrosoftVTableContext::hasVtableSlot(MD) &&
-        !isa<CXXDestructorDecl>(MD) && !MD->isPure())
+        !isa<CXXDestructorDecl>(MD) && !MD->isPureVirtual())
       Work.insert(MD);
   while (!Work.empty()) {
     const CXXMethodDecl *MD = *Work.begin();
diff --git a/clang/lib/AST/TextNodeDumper.cpp b/clang/lib/AST/TextNodeDumper.cpp
index 369ff66ac4dbc..48c6729a67381 100644
--- a/clang/lib/AST/TextNodeDumper.cpp
+++ b/clang/lib/AST/TextNodeDumper.cpp
@@ -1875,7 +1875,7 @@ void TextNodeDumper::VisitFunctionDecl(const FunctionDecl *D) {
   if (D->isModulePrivate())
     OS << " __module_private__";
 
-  if (D->isPure())
+  if (D->isPureVirtual())
     OS << " pure";
   if (D->isDefaulted()) {
     OS << " default";
diff --git a/clang/lib/AST/VTableBuilder.cpp b/clang/lib/AST/VTableBuilder.cpp
index 69861c65f6e3a..a956ca5b37acf 100644
--- a/clang/lib/AST/VTableBuilder.cpp
+++ b/clang/lib/AST/VTableBuilder.cpp
@@ -422,7 +422,7 @@ void FinalOverriders::dump(raw_ostream &Out, BaseSubobject Base,
     Out << ", " << Overrider.Offset.getQuantity() << ')';
 
     BaseOffset Offset;
-    if (!Overrider.Method->isPure())
+    if (!Overrider.Method->isPureVirtual())
       Offset = ComputeReturnAdjustmentBaseOffset(Context, Overrider.Method, MD);
 
     if (!Offset.isEmpty()) {
@@ -1261,7 +1261,7 @@ ThisAdjustment ItaniumVTableBuilder::ComputeThisAdjustment(
     const CXXMethodDecl *MD, CharUnits BaseOffsetInLayoutClass,
     FinalOverriders::OverriderInfo Overrider) {
   // Ignore adjustments for pure virtual member functions.
-  if (Overrider.Method->isPure())
+  if (Overrider.Method->isPureVirtual())
     return ThisAdjustment();
 
   BaseSubobject OverriddenBaseSubobject(MD->getParent(),
@@ -1607,7 +1607,7 @@ void ItaniumVTableBuilder::AddMethods(
     // Check if this overrider needs a return adjustment.
     // We don't want to do this for pure virtual member functions.
     BaseOffset ReturnAdjustmentOffset;
-    if (!OverriderMD->isPure()) {
+    if (!OverriderMD->isPureVirtual()) {
       ReturnAdjustmentOffset =
         ComputeReturnAdjustmentBaseOffset(Context, OverriderMD, MD);
     }
@@ -1959,7 +1959,7 @@ void ItaniumVTableBuilder::dumpLayout(raw_ostream &Out) {
       std::string Str = PredefinedExpr::ComputeName(
           PredefinedIdentKind::PrettyFunctionNoVirtual, MD);
       Out << Str;
-      if (MD->isPure())
+      if (MD->isPureVirtual())
         Out << " [pure]";
 
       if (MD->isDeleted())
@@ -2010,7 +2010,7 @@ void ItaniumVTableBuilder::dumpLayout(raw_ostream &Out) {
       else
         Out << "() [deleting]";
 
-      if (DD->isPure())
+      if (DD->isPureVirtual())
         Out << " [pure]";
 
       ThunkInfo Thunk = VTableThunks.lookup(I);
@@ -2038,7 +2038,7 @@ void ItaniumVTableBuilder::dumpLayout(raw_ostream &Out) {
       std::string Str = PredefinedExpr::ComputeName(
           PredefinedIdentKind::PrettyFunctionNoVirtual, MD);
       Out << "[unused] " << Str;
-      if (MD->isPure())
+      if (MD->isPureVirtual())
         Out << " [pure]";
     }
 
@@ -3076,7 +3076,7 @@ void VFTableBuilder::AddMethods(BaseSubobject Base, unsigned BaseDepth,
     // We don't want to do this for pure virtual member functions.
     BaseOffset ReturnAdjustmentOffset;
     ReturnAdjustment ReturnAdjustment;
-    if (!FinalOverriderMD->isPure()) {
+    if (!FinalOverriderMD->isPureVirtual()) {
       ReturnAdjustmentOffset =
           ComputeReturnAdjustmentBaseOffset(Context, FinalOverriderMD, MD);
     }
@@ -3175,7 +3175,7 @@ void VFTableBuilder::dumpLayout(raw_ostream &Out) {
       std::string Str = PredefinedExpr::ComputeName(
           PredefinedIdentKind::PrettyFunctionNoVirtual, MD);
       Out << Str;
-      if (MD->isPure())
+      if (MD->isPureVirtual())
         Out << " [pure]";
 
       if (MD->isDeleted())
@@ -3194,7 +3194,7 @@ void VFTableBuilder::dumpLayout(raw_ostream &Out) {
       DD->printQualifiedName(Out);
       Out << "() [scalar deleting]";
 
-      if (DD->isPure())
+      if (DD->isPureVirtual())
         Out << " [pure]";
 
       ThunkInfo Thunk = VTableThunks.lookup(I);
diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index 236d53bee4e8f..c5b96f93b42c3 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -1926,7 +1926,7 @@ llvm::DISubprogram *CGDebugInfo::CreateCXXMemberFunction(
   int ThisAdjustment = 0;
 
   if (VTableContextBase::hasVtableSlot(Method)) {
-    if (Method->isPure())
+    if (Method->isPureVirtual())
       SPFlags |= llvm::DISubprogram::SPFlagPureVirtual;
     else
       SPFlags |= llvm::DISubprogram::SPFlagVirtual;
diff --git a/clang/lib/CodeGen/CGVTables.cpp b/clang/lib/CodeGen/CGVTables.cpp
index 27a2cab4f7531..8dee3f74b44b4 100644
--- a/clang/lib/CodeGen/CGVTables.cpp
+++ b/clang/lib/CodeGen/CGVTables.cpp
@@ -793,7 +793,7 @@ void CodeGenVTables::addVTableComponent(ConstantArrayBuilder &builder,
     llvm::Constant *fnPtr;
 
     // Pure virtual member functions.
-    if (cast<CXXMethodDecl>(GD.getDecl())->isPure()) {
+    if (cast<CXXMethodDecl>(GD.getDecl())->isPureVirtual()) {
       if (!PureVirtualFn)
         PureVirtualFn =
             getSpecialVirtualFn(CGM.getCXXABI().GetPureVirtualCallName());
diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp
index cafbecebc8a11..70832d1a14552 100644
--- a/clang/lib/Sema/Sema.cpp
+++ b/clang/lib/Sema/Sema.cpp
@@ -957,7 +957,7 @@ static bool MethodsAndNestedClassesComplete(const CXXRecordDecl *RD,
        I != E && Complete; ++I) {
     if (const CXXMethodDecl *M = dyn_cast<CXXMethodDecl>(*I))
       Complete = M->isDefined() || M->isDefaulted() ||
-                 (M->isPure() && !isa<CXXDestructorDecl>(M));
+                 (M->isPureVirtual() && !isa<CXXDestructorDecl>(M));
     else if (const FunctionTemplateDecl *F = dyn_cast<FunctionTemplateDecl>(*I))
       // If the template function is marked as late template parsed at this
       // point, it has not been instantiated and therefore we have not
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index eb28631ee6939..cbb8ed8ce34d1 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -4390,8 +4390,8 @@ bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old,
   mergeDeclAttributes(New, Old);
 
   // Merge "pure" flag.
-  if (Old->isPure())
-    New->setPure();
+  if (Old->isPureVirtual())
+    New->setIsPureVirtual();
 
   // Merge "used" flag.
   if (Old->getMostRecentDecl()->isUsed(false))
@@ -9878,7 +9878,7 @@ Sema::ActOnFunctionDeclarator(Scope *S, Declarator &D, DeclContext *DC,
     if (const CXXRecordDecl *Parent =
           dyn_cast<CXXRecordDecl>(NewFD->getDeclContext())) {
       if (Parent->isInterface() && cast<CXXMethodDecl>(NewFD)->isUserProvided())
-        NewFD->setPure(true);
+        NewFD->setIsPureVirtual(true);
 
       // C++ [class.union]p2
       //   A union can have member functions, but not virtual functions.
@@ -16012,7 +16012,8 @@ Decl *Sema::ActOnFinishFunctionBody(Decl *dcl, Stmt *Body,
 
       // MSVC permits the use of pure specifier (=0) on function definition,
       // defined at class scope, warn about this non-standard construct.
-      if (getLangOpts().MicrosoftExt && FD->isPure() && !FD->isOutOfLine())
+      if (getLangOpts().MicrosoftExt && FD->isPureVirtual() &&
+          !FD->isOutOfLine())
         Diag(FD->getLocation(), diag::ext_pure_function_definition);
 
       if (!FD->isInvalidDecl()) {
diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index 62dc623d5af37..828a0ec3dd042 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -6062,7 +6062,7 @@ void Sema::DiagnoseAbstractType(const CXXRecordDecl *RD) {
       if (SO->second.size() != 1)
         continue;
 
-      if (!SO->second.front().Method->isPure())
+      if (!SO->second.front().Method->isPureVirtual())
         continue;
 
       if (!SeenPureMethods.insert(SO->second.front().Method).second)
@@ -18495,7 +18495,7 @@ bool Sema::CheckPureMethod(CXXMethodDecl *Method, SourceRange InitRange) {
     Method->setRangeEnd(EndLoc);
 
   if (Method->isVirtual() || Method->getParent()->isDependentContext()) {
-    Method->setPure();
+    Method->setIsPureVirtual();
     return false;
   }
 
@@ -18766,7 +18766,7 @@ bool Sema::DefineUsedVTables() {
 void Sema::MarkVirtualMemberExceptionSpecsNeeded(SourceLocation Loc,
                                                  const CXXRecordDecl *RD) {
   for (const auto *I : RD->methods())
-    if (I->isVirtual() && !I->isPure())
+    if (I->isVirtual() && !I->isPureVirtual())
       ResolveExceptionSpec(Loc, I->getType()->castAs<FunctionProtoType>());
 }
 
@@ -18787,7 +18787,8 @@ void Sema::MarkVirtualMembersReferenced(SourceLocation Loc,
 
       // C++ [basic.def.odr]p2:
       //   [...] A virtual member function is used if it is not pure. [...]
-      if (!Overrider->isPure() && (!ConstexprOnly || Overrider->isConstexpr()))
+      if (!Overrider->isPureVirtual() &&
+          (!ConstexprOnly || Overrider->isConstexpr()))
         MarkFunctionReferenced(Loc, Overrider);
     }
   }
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index 3df0ec5176743..6413a48f809ac 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -20769,7 +20769,7 @@ void Sema::MarkMemberReferenced(MemberExpr *E) {
   bool MightBeOdrUse = true;
   if (E->performsVirtualDispatch(getLangOpts())) {
     if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(E->getMemberDecl()))
-      if (Method->isPure())
+      if (Method->isPureVirtual())
         MightBeOdrUse = false;
   }
   SourceLocation Loc =
diff --git a/clang/lib/Sema/SemaOverload.cpp b/clang/lib/Sema/SemaOverload.cpp
index 37c62b306b3cd..bbbd0abc82d74 100644
--- a/clang/lib/Sema/SemaOverload.cpp
+++ b/clang/lib/Sema/SemaOverload.cpp
@@ -15472,7 +15472,7 @@ ExprResult Sema::BuildCallToMemberFunction(Scope *S, Expr *MemExprE,
   }
 
   if (isa<CXXConstructorDecl, CXXDestructorDecl>(CurContext) &&
-      TheCall->getDirectCallee()->isPure()) {
+      TheCall->getDirectCallee()->isPureVirtual()) {
     const FunctionDecl *MD = TheCall->getDirectCallee();
 
     if (isa<CXXThisExpr>(MemExpr->getBase()->IgnoreParenCasts()) &&
diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
index 208a7b120c419..fbc8572ea0e0f 100644
--- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -2755,7 +2755,7 @@ Decl *TemplateDeclInstantiator::VisitCXXMethodDecl(
                                    IsExplicitSpecialization,
                                    Method->isThisDeclarationADefinition());
 
-  if (D->isPure())
+  if (D->isPureVirtual())
     SemaRef.CheckPureMethod(Method, SourceRange());
 
   // Propagate access.  For a non-friend declaration, the access is
diff --git a/clang/lib/Serialization/ASTReaderDecl.cpp b/clang/lib/Serialization/ASTReaderDecl.cpp
index 596cd891772f1..a149d82153037 100644
--- a/clang/lib/Serialization/ASTReaderDecl.cpp
+++ b/clang/lib/Serialization/ASTReaderDecl.cpp
@@ -1135,7 +1135,7 @@ void ASTDeclReader::VisitFunctionDecl(FunctionDecl *FD) {
 
   // Defer calling `setPure` until merging above has guaranteed we've set
   // `DefinitionData` (as this will need to access it).
-  FD->setPure(Pure);
+  FD->setIsPureVirtual(Pure);
 
   // Read in the parameters.
   unsigned NumParams = Record.readInt();
diff --git a/clang/lib/Serialization/ASTWriterDecl.cpp b/clang/lib/Serialization/ASTWriterDecl.cpp
index 9e3299f049184..bb1f51786d281 100644
--- a/clang/lib/Serialization/ASTWriterDecl.cpp
+++ b/clang/lib/Serialization/ASTWriterDecl.cpp
@@ -680,7 +680,7 @@ void ASTDeclWriter::VisitFunctionDecl(FunctionDecl *D) {
   FunctionDeclBits.addBit(D->isInlined());
   FunctionDeclBits.addBit(D->hasSkippedBody());
   FunctionDeclBits.addBit(D->isVirtualAsWritten());
-  FunctionDeclBits.addBit(D->isPure());
+  FunctionDeclBits.addBit(D->isPureVirtual());
   FunctionDeclBits.addBit(D->hasInheritedPrototype());
   FunctionDeclBits.addBit(D->hasWrittenPrototype());
   FunctionDeclBits.addBit(D->isDeletedBit());
diff --git a/clang/lib/StaticAnalyzer/Checkers/VirtualCallChecker.cpp b/clang/lib/StaticAnalyzer/Checkers/VirtualCallChecker.cpp
index 1c589e3468c2d..33a9a07f9d32d 100644
--- a/clang/lib/StaticAnalyzer/Checkers/VirtualCallChecker.cpp
+++ b/clang/lib/StaticAnalyzer/Checkers/VirtualCallChecker.cpp
@@ -116,7 +116,7 @@ void VirtualCallChecker::checkPreCall(const CallEvent &Call,
   if (!ObState)
     return;
 
-  bool IsPure = MD->isPure();
+  bool IsPure = MD->isPureVirtual();
 
   // At this point we're sure that we're calling a virtual method
   // during construction or destruction, so we'll emit a report.
diff --git a/clang/tools/libclang/CIndex.cpp b/clang/tools/libclang/CIndex.cpp
index 841522a0f4788..00c0dff9cce4c 100644
--- a/clang/tools/libclang/CIndex.cpp
+++ b/clang/tools/libclang/CIndex.cpp
@@ -9007,7 +9007,7 @@ unsigned clang_CXXMethod_isPureVirtual(CXCursor C) {
   const Decl *D = cxcursor::getCursorDecl(C);
   const CXXMethodDecl *Method =
       D ? dyn_cast_or_null<CXXMethodDecl>(D->getAsFunction()) : nullptr;
-  return (Method && Method->isVirtual() && Method->isPure()) ? 1 : 0;
+  return (Method && Method->isPureVirtual()) ? 1 : 0;
 }
 
 unsigned clang_CXXMethod_isConst(CXCursor C) {