Add a const overload for ObjCInterfaceDecl::all_declared_ivar_begin.

This was previously not-const only because it has to lazily construct a chain
of ivars the first time it is called (and after the chain is invalidated).
In practice, all the clients were just const_casting their const Decls;
all those now-unnecessary const_casts have been removed.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@135741 91177308-0d34-0410-b5e6-96231b3b80d8

Author: belkadan

include/clang/AST/ASTContext.h

@@ -1163,13 +1163,9 @@ class ASTContext : public llvm::RefCountedBase<ASTContext> {
   bool isNearlyEmpty(const CXXRecordDecl *RD) const;
 
   MangleContext *createMangleContext();
-
-  void ShallowCollectObjCIvars(const ObjCInterfaceDecl *OI,
-                               SmallVectorImpl<ObjCIvarDecl*> &Ivars)
-    const;
 
   void DeepCollectObjCIvars(const ObjCInterfaceDecl *OI, bool leafClass,
-                            SmallVectorImpl<ObjCIvarDecl*> &Ivars) const;
+                            SmallVectorImpl<const ObjCIvarDecl*> &Ivars) const;
 
   unsigned CountNonClassIvars(const ObjCInterfaceDecl *OI) const;
   void CollectInheritedProtocols(const Decl *CDecl,

include/clang/AST/DeclObjC.h

@@ -576,7 +576,7 @@ class ObjCInterfaceDecl : public ObjCContainerDecl {
 
   typedef specific_decl_iterator<ObjCIvarDecl> ivar_iterator;
 
-  ivar_iterator ivar_begin() const { return  ivar_iterator(decls_begin()); }
+  ivar_iterator ivar_begin() const { return ivar_iterator(decls_begin()); }
   ivar_iterator ivar_end() const { return ivar_iterator(decls_end()); }
 
   unsigned ivar_size() const {
@@ -585,7 +585,12 @@ class ObjCInterfaceDecl : public ObjCContainerDecl {
 
   bool ivar_empty() const { return ivar_begin() == ivar_end(); }
 
-  ObjCIvarDecl  *all_declared_ivar_begin();
+  ObjCIvarDecl *all_declared_ivar_begin();
+  const ObjCIvarDecl *all_declared_ivar_begin() const {
+    // Even though this modifies IvarList, it's conceptually const:
+    // the ivar chain is essentially a cached property of ObjCInterfaceDecl.
+    return const_cast<ObjCInterfaceDecl *>(this)->all_declared_ivar_begin();
+  }
   void setIvarList(ObjCIvarDecl *ivar) { IvarList = ivar; }
 
   /// setProtocolList - Set the list of protocols that this interface
@@ -754,6 +759,7 @@ class ObjCIvarDecl : public FieldDecl {
   const ObjCInterfaceDecl *getContainingInterface() const;
 
   ObjCIvarDecl *getNextIvar() { return NextIvar; }
+  const ObjCIvarDecl *getNextIvar() const { return NextIvar; }
   void setNextIvar(ObjCIvarDecl *ivar) { NextIvar = ivar; }
 
   void setAccessControl(AccessControl ac) { DeclAccess = ac; }

lib/AST/ASTContext.cpp

@@ -1063,19 +1063,6 @@ unsigned ASTContext::getPreferredTypeAlign(const Type *T) const {
   return ABIAlign;
 }
 
-/// ShallowCollectObjCIvars -
-/// Collect all ivars, including those synthesized, in the current class.
-///
-void ASTContext::ShallowCollectObjCIvars(const ObjCInterfaceDecl *OI,
-                            llvm::SmallVectorImpl<ObjCIvarDecl*> &Ivars) const {
-  // FIXME. This need be removed but there are two many places which
-  // assume const-ness of ObjCInterfaceDecl
-  ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl *>(OI);
-  for (ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv; 
-        Iv= Iv->getNextIvar())
-    Ivars.push_back(Iv);
-}
-
 /// DeepCollectObjCIvars -
 /// This routine first collects all declared, but not synthesized, ivars in
 /// super class and then collects all ivars, including those synthesized for
@@ -1084,7 +1071,7 @@ void ASTContext::ShallowCollectObjCIvars(const ObjCInterfaceDecl *OI,
 ///
 void ASTContext::DeepCollectObjCIvars(const ObjCInterfaceDecl *OI,
                                       bool leafClass,
-                            llvm::SmallVectorImpl<ObjCIvarDecl*> &Ivars) const {
+                            SmallVectorImpl<const ObjCIvarDecl*> &Ivars) const {
   if (const ObjCInterfaceDecl *SuperClass = OI->getSuperClass())
     DeepCollectObjCIvars(SuperClass, false, Ivars);
   if (!leafClass) {
@@ -1094,7 +1081,7 @@ void ASTContext::DeepCollectObjCIvars(const ObjCInterfaceDecl *OI,
   }
   else {
     ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl *>(OI);
-    for (ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv; 
+    for (const ObjCIvarDecl *Iv = IDecl->all_declared_ivar_begin(); Iv; 
          Iv= Iv->getNextIvar())
       Ivars.push_back(Iv);
   }
@@ -4487,10 +4474,10 @@ void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
     const IdentifierInfo *II = OI->getIdentifier();
     S += II->getName();
     S += '=';
-    llvm::SmallVector<ObjCIvarDecl*, 32> Ivars;
+    SmallVector<const ObjCIvarDecl*, 32> Ivars;
     DeepCollectObjCIvars(OI, true, Ivars);
     for (unsigned i = 0, e = Ivars.size(); i != e; ++i) {
-      FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
+      const FieldDecl *Field = cast<FieldDecl>(Ivars[i]);
       if (Field->isBitField())
         getObjCEncodingForTypeImpl(Field->getType(), S, false, true, Field);
       else

lib/AST/RecordLayoutBuilder.cpp

@@ -1242,10 +1242,9 @@ void RecordLayoutBuilder::Layout(const ObjCInterfaceDecl *D) {
   }
 
   InitializeLayout(D);
-  ObjCInterfaceDecl *OI = const_cast<ObjCInterfaceDecl*>(D);
   // Layout each ivar sequentially.
-  for (ObjCIvarDecl *IVD = OI->all_declared_ivar_begin(); 
-       IVD; IVD = IVD->getNextIvar())
+  for (const ObjCIvarDecl *IVD = D->all_declared_ivar_begin(); IVD;
+       IVD = IVD->getNextIvar())
     LayoutField(IVD);
 
   // Finally, round the size of the total struct up to the alignment of the

lib/CodeGen/CGObjC.cpp

@@ -716,9 +716,8 @@ static void emitCXXDestructMethod(CodeGenFunction &CGF,
 
   llvm::Value *self = CGF.LoadObjCSelf();
 
-  ObjCInterfaceDecl *iface
-    = const_cast<ObjCInterfaceDecl*>(impl->getClassInterface());
-  for (ObjCIvarDecl *ivar = iface->all_declared_ivar_begin();
+  const ObjCInterfaceDecl *iface = impl->getClassInterface();
+  for (const ObjCIvarDecl *ivar = iface->all_declared_ivar_begin();
        ivar; ivar = ivar->getNextIvar()) {
     QualType type = ivar->getType();
 

lib/CodeGen/CGObjCGNU.cpp

@@ -1859,12 +1859,8 @@ void CGObjCGNU::GenerateClass(const ObjCImplementationDecl *OID) {
     instanceSize = 0 - (instanceSize - superInstanceSize);
   }
 
-  // Collect declared and synthesized ivars.
-  llvm::SmallVector<ObjCIvarDecl*, 16> OIvars;
-  CGM.getContext().ShallowCollectObjCIvars(ClassDecl, OIvars);
-
-  for (unsigned i = 0, e = OIvars.size(); i != e; ++i) {
-      ObjCIvarDecl *IVD = OIvars[i];
+  for (const ObjCIvarDecl *IVD = ClassDecl->all_declared_ivar_begin(); IVD;
+       IVD = IVD->getNextIvar()) {
       // Store the name
       IvarNames.push_back(MakeConstantString(IVD->getNameAsString()));
       // Get the type encoding for this ivar
@@ -1968,12 +1964,12 @@ void CGObjCGNU::GenerateClass(const ObjCImplementationDecl *OID) {
       llvm::ConstantInt::get(IndexTy, 1), 0,
       llvm::ConstantInt::get(IndexTy, 2) };
 
-
-  for (unsigned i = 0, e = OIvars.size(); i != e; ++i) {
-      ObjCIvarDecl *IVD = OIvars[i];
+  unsigned ivarIndex = 0;
+  for (const ObjCIvarDecl *IVD = ClassDecl->all_declared_ivar_begin(); IVD;
+       IVD = IVD->getNextIvar()) {
       const std::string Name = "__objc_ivar_offset_" + ClassName + '.'
           + IVD->getNameAsString();
-      offsetPointerIndexes[2] = llvm::ConstantInt::get(IndexTy, i);
+      offsetPointerIndexes[2] = llvm::ConstantInt::get(IndexTy, ivarIndex);
       // Get the correct ivar field
       llvm::Constant *offsetValue = llvm::ConstantExpr::getGetElementPtr(
               IvarList, offsetPointerIndexes);
@@ -1990,6 +1986,7 @@ void CGObjCGNU::GenerateClass(const ObjCImplementationDecl *OID) {
           offset = new llvm::GlobalVariable(TheModule, offsetValue->getType(),
                   false, llvm::GlobalValue::ExternalLinkage, offsetValue, Name);
       }
+      ++ivarIndex;
   }
   //Generate metaclass for class methods
   llvm::Constant *MetaClassStruct = GenerateClassStructure(NULLPtr,
@@ -2432,10 +2429,9 @@ LValue CGObjCGNU::EmitObjCValueForIvar(CodeGenFunction &CGF,
 static const ObjCInterfaceDecl *FindIvarInterface(ASTContext &Context,
                                                   const ObjCInterfaceDecl *OID,
                                                   const ObjCIvarDecl *OIVD) {
-  llvm::SmallVector<ObjCIvarDecl*, 16> Ivars;
-  Context.ShallowCollectObjCIvars(OID, Ivars);
-  for (unsigned k = 0, e = Ivars.size(); k != e; ++k) {
-    if (OIVD == Ivars[k])
+  for (const ObjCIvarDecl *next = OID->all_declared_ivar_begin(); next;
+       next = next->getNextIvar()) {
+    if (OIVD == next)
       return OID;
   }
 

lib/CodeGen/CGObjCMac.cpp

@@ -775,7 +775,7 @@ class CGObjCCommonMac : public CodeGen::CGObjCRuntime {
   void BuildAggrIvarLayout(const ObjCImplementationDecl *OI,
                            const llvm::StructLayout *Layout,
                            const RecordDecl *RD,
-                           const llvm::SmallVectorImpl<FieldDecl*> &RecFields,
+                           const SmallVectorImpl<const FieldDecl*> &RecFields,
                            unsigned int BytePos, bool ForStrongLayout,
                            bool &HasUnion);
 
@@ -2407,10 +2407,9 @@ llvm::Constant *CGObjCMac::EmitIvarList(const ObjCImplementationDecl *ID,
   if (ForClass)
     return llvm::Constant::getNullValue(ObjCTypes.IvarListPtrTy);
 
-  ObjCInterfaceDecl *OID =
-    const_cast<ObjCInterfaceDecl*>(ID->getClassInterface());
+  const ObjCInterfaceDecl *OID = ID->getClassInterface();
 
-  for (ObjCIvarDecl *IVD = OID->all_declared_ivar_begin(); 
+  for (const ObjCIvarDecl *IVD = OID->all_declared_ivar_begin(); 
        IVD; IVD = IVD->getNextIvar()) {
     // Ignore unnamed bit-fields.
     if (!IVD->getDeclName())
@@ -3574,7 +3573,7 @@ void CGObjCCommonMac::BuildAggrIvarRecordLayout(const RecordType *RT,
                                                 bool &HasUnion) {
   const RecordDecl *RD = RT->getDecl();
   // FIXME - Use iterator.
-  llvm::SmallVector<FieldDecl*, 16> Fields(RD->field_begin(), RD->field_end());
+  SmallVector<const FieldDecl*, 16> Fields(RD->field_begin(), RD->field_end());
   llvm::Type *Ty = CGM.getTypes().ConvertType(QualType(RT, 0));
   const llvm::StructLayout *RecLayout =
     CGM.getTargetData().getStructLayout(cast<llvm::StructType>(Ty));
@@ -3586,15 +3585,15 @@ void CGObjCCommonMac::BuildAggrIvarRecordLayout(const RecordType *RT,
 void CGObjCCommonMac::BuildAggrIvarLayout(const ObjCImplementationDecl *OI,
                              const llvm::StructLayout *Layout,
                              const RecordDecl *RD,
-                             const llvm::SmallVectorImpl<FieldDecl*> &RecFields,
+                             const SmallVectorImpl<const FieldDecl*> &RecFields,
                              unsigned int BytePos, bool ForStrongLayout,
                              bool &HasUnion) {
   bool IsUnion = (RD && RD->isUnion());
   uint64_t MaxUnionIvarSize = 0;
   uint64_t MaxSkippedUnionIvarSize = 0;
-  FieldDecl *MaxField = 0;
-  FieldDecl *MaxSkippedField = 0;
-  FieldDecl *LastFieldBitfieldOrUnnamed = 0;
+  const FieldDecl *MaxField = 0;
+  const FieldDecl *MaxSkippedField = 0;
+  const FieldDecl *LastFieldBitfieldOrUnnamed = 0;
   uint64_t MaxFieldOffset = 0;
   uint64_t MaxSkippedFieldOffset = 0;
   uint64_t LastBitfieldOrUnnamedOffset = 0;
@@ -3605,13 +3604,13 @@ void CGObjCCommonMac::BuildAggrIvarLayout(const ObjCImplementationDecl *OI,
   unsigned WordSizeInBits = CGM.getContext().Target.getPointerWidth(0);
   unsigned ByteSizeInBits = CGM.getContext().Target.getCharWidth();
   if (!RD && CGM.getLangOptions().ObjCAutoRefCount) {
-    FieldDecl *FirstField = RecFields[0];
+    const FieldDecl *FirstField = RecFields[0];
     FirstFieldDelta = 
       ComputeIvarBaseOffset(CGM, OI, cast<ObjCIvarDecl>(FirstField));
   }
 
   for (unsigned i = 0, e = RecFields.size(); i != e; ++i) {
-    FieldDecl *Field = RecFields[i];
+    const FieldDecl *Field = RecFields[i];
     uint64_t FieldOffset;
     if (RD) {
       // Note that 'i' here is actually the field index inside RD of Field,
@@ -3903,20 +3902,19 @@ llvm::Constant *CGObjCCommonMac::BuildIvarLayout(
       !CGM.getLangOptions().ObjCAutoRefCount)
     return llvm::Constant::getNullValue(PtrTy);
 
-  ObjCInterfaceDecl *OI = 
-    const_cast<ObjCInterfaceDecl*>(OMD->getClassInterface());
-  llvm::SmallVector<FieldDecl*, 32> RecFields;
+  const ObjCInterfaceDecl *OI = OMD->getClassInterface();
+  SmallVector<const FieldDecl*, 32> RecFields;
   if (CGM.getLangOptions().ObjCAutoRefCount) {
-    for (ObjCIvarDecl *IVD = OI->all_declared_ivar_begin(); 
+    for (const ObjCIvarDecl *IVD = OI->all_declared_ivar_begin(); 
          IVD; IVD = IVD->getNextIvar())
       RecFields.push_back(cast<FieldDecl>(IVD));
   }
   else {
-    llvm::SmallVector<ObjCIvarDecl*, 32> Ivars;
+    SmallVector<const ObjCIvarDecl*, 32> Ivars;
     CGM.getContext().DeepCollectObjCIvars(OI, true, Ivars);
 
-    for (unsigned k = 0, e = Ivars.size(); k != e; ++k)
-      RecFields.push_back(cast<FieldDecl>(Ivars[k]));
+    // FIXME: This is not ideal; we shouldn't have to do this copy.
+    RecFields.append(Ivars.begin(), Ivars.end());
   }
 
   if (RecFields.empty())
@@ -5258,13 +5256,12 @@ llvm::Constant *CGObjCNonFragileABIMac::EmitIvarList(
 
   std::vector<llvm::Constant*> Ivars, Ivar(5);
 
-  ObjCInterfaceDecl *OID = 
-    const_cast<ObjCInterfaceDecl*>(ID->getClassInterface());
+  const ObjCInterfaceDecl *OID = ID->getClassInterface();
   assert(OID && "CGObjCNonFragileABIMac::EmitIvarList - null interface");
 
   // FIXME. Consolidate this with similar code in GenerateClass.
 
-  for (ObjCIvarDecl *IVD = OID->all_declared_ivar_begin(); 
+  for (const ObjCIvarDecl *IVD = OID->all_declared_ivar_begin(); 
        IVD; IVD = IVD->getNextIvar()) {
     // Ignore unnamed bit-fields.
     if (!IVD->getDeclName())

lib/CodeGen/CGObjCRuntime.cpp

@@ -52,9 +52,8 @@ static uint64_t LookupFieldBitOffset(CodeGen::CodeGenModule &CGM,
   // implemented. This should be fixed to get the information from the layout
   // directly.
   unsigned Index = 0;
-  ObjCInterfaceDecl *IDecl = const_cast<ObjCInterfaceDecl*>(Container);
 
-  for (ObjCIvarDecl *IVD = IDecl->all_declared_ivar_begin(); 
+  for (const ObjCIvarDecl *IVD = Container->all_declared_ivar_begin(); 
        IVD; IVD = IVD->getNextIvar()) {
     if (Ivar == IVD)
       break;

lib/CodeGen/CodeGenModule.cpp

@@ -2001,9 +2001,8 @@ void CodeGenModule::EmitObjCPropertyImplementations(const
 }
 
 static bool needsDestructMethod(ObjCImplementationDecl *impl) {
-  ObjCInterfaceDecl *iface
-    = const_cast<ObjCInterfaceDecl*>(impl->getClassInterface());
-  for (ObjCIvarDecl *ivar = iface->all_declared_ivar_begin();
+  const ObjCInterfaceDecl *iface = impl->getClassInterface();
+  for (const ObjCIvarDecl *ivar = iface->all_declared_ivar_begin();
        ivar; ivar = ivar->getNextIvar())
     if (ivar->getType().isDestructedType())
       return true;

lib/Sema/SemaDeclObjC.cpp

@@ -2533,11 +2533,11 @@ void Sema::ActOnDefs(Scope *S, Decl *TagD, SourceLocation DeclStart,
   }
 
   // Collect the instance variables
-  llvm::SmallVector<ObjCIvarDecl*, 32> Ivars;
+  SmallVector<const ObjCIvarDecl*, 32> Ivars;
   Context.DeepCollectObjCIvars(Class, true, Ivars);
   // For each ivar, create a fresh ObjCAtDefsFieldDecl.
   for (unsigned i = 0; i < Ivars.size(); i++) {
-    FieldDecl* ID = cast<FieldDecl>(Ivars[i]);
+    const FieldDecl* ID = cast<FieldDecl>(Ivars[i]);
     RecordDecl *Record = dyn_cast<RecordDecl>(TagD);
     Decl *FD = ObjCAtDefsFieldDecl::Create(Context, Record,
                                            /*FIXME: StartL=*/ID->getLocation(),