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//===--- SemaExprObjC.cpp - Semantic Analysis for ObjC Expressions --------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements semantic analysis for Objective-C expressions.
//
//===----------------------------------------------------------------------===//
#include "Sema.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/DeclObjC.h"
#include "clang/AST/ExprObjC.h"
#include "llvm/ADT/SmallString.h"
#include "clang/Lex/Preprocessor.h"
using namespace clang;
Sema::ExprResult Sema::ParseObjCStringLiteral(SourceLocation *AtLocs,
ExprTy **strings,
unsigned NumStrings) {
StringLiteral **Strings = reinterpret_cast<StringLiteral**>(strings);
// Most ObjC strings are formed out of a single piece. However, we *can*
// have strings formed out of multiple @ strings with multiple pptokens in
// each one, e.g. @"foo" "bar" @"baz" "qux" which need to be turned into one
// StringLiteral for ObjCStringLiteral to hold onto.
StringLiteral *S = Strings[0];
// If we have a multi-part string, merge it all together.
if (NumStrings != 1) {
// Concatenate objc strings.
llvm::SmallString<128> StrBuf;
llvm::SmallVector<SourceLocation, 8> StrLocs;
for (unsigned i = 0; i != NumStrings; ++i) {
S = Strings[i];
// ObjC strings can't be wide.
if (S->isWide()) {
Diag(S->getLocStart(), diag::err_cfstring_literal_not_string_constant)
<< S->getSourceRange();
return true;
}
// Get the string data.
StrBuf.append(S->getStrData(), S->getStrData()+S->getByteLength());
// Get the locations of the string tokens.
StrLocs.append(S->tokloc_begin(), S->tokloc_end());
// Free the temporary string.
S->Destroy(Context);
}
// Create the aggregate string with the appropriate content and location
// information.
S = StringLiteral::Create(Context, &StrBuf[0], StrBuf.size(), false,
Context.getPointerType(Context.CharTy),
&StrLocs[0], StrLocs.size());
}
// Verify that this composite string is acceptable for ObjC strings.
if (CheckObjCString(S))
return true;
// Initialize the constant string interface lazily. This assumes
// the NSConstantString interface is seen in this translation unit.
QualType Ty = Context.getObjCConstantStringInterface();
if (!Ty.isNull()) {
Ty = Context.getPointerType(Ty);
} else {
IdentifierInfo *NSIdent = &Context.Idents.get("NSConstantString");
NamedDecl *IF = LookupName(TUScope, NSIdent, LookupOrdinaryName);
if (ObjCInterfaceDecl *StrIF = dyn_cast_or_null<ObjCInterfaceDecl>(IF)) {
Context.setObjCConstantStringInterface(StrIF);
Ty = Context.getObjCConstantStringInterface();
Ty = Context.getPointerType(Ty);
} else {
// If there is no NSConstantString interface defined then treat constant
// strings as untyped objects and let the runtime figure it out later.
Ty = Context.getObjCIdType();
}
}
return new (Context) ObjCStringLiteral(S, Ty, AtLocs[0]);
}
Sema::ExprResult Sema::ParseObjCEncodeExpression(SourceLocation AtLoc,
SourceLocation EncodeLoc,
SourceLocation LParenLoc,
TypeTy *ty,
SourceLocation RParenLoc) {
QualType EncodedType = QualType::getFromOpaquePtr(ty);
std::string Str;
Context.getObjCEncodingForType(EncodedType, Str);
// The type of @encode is the same as the type of the corresponding string,
// which is an array type.
QualType StrTy = Context.CharTy;
// A C++ string literal has a const-qualified element type (C++ 2.13.4p1).
if (getLangOptions().CPlusPlus)
StrTy.addConst();
StrTy = Context.getConstantArrayType(StrTy, llvm::APInt(32, Str.size()+1),
ArrayType::Normal, 0);
return new (Context) ObjCEncodeExpr(StrTy, EncodedType, AtLoc, RParenLoc);
}
Sema::ExprResult Sema::ParseObjCSelectorExpression(Selector Sel,
SourceLocation AtLoc,
SourceLocation SelLoc,
SourceLocation LParenLoc,
SourceLocation RParenLoc) {
QualType Ty = Context.getObjCSelType();
return new (Context) ObjCSelectorExpr(Ty, Sel, AtLoc, RParenLoc);
}
Sema::ExprResult Sema::ParseObjCProtocolExpression(IdentifierInfo *ProtocolId,
SourceLocation AtLoc,
SourceLocation ProtoLoc,
SourceLocation LParenLoc,
SourceLocation RParenLoc) {
ObjCProtocolDecl* PDecl = ObjCProtocols[ProtocolId];
if (!PDecl) {
Diag(ProtoLoc, diag::err_undeclared_protocol) << ProtocolId;
return true;
}
QualType Ty = Context.getObjCProtoType();
if (Ty.isNull())
return true;
Ty = Context.getPointerType(Ty);
return new (Context) ObjCProtocolExpr(Ty, PDecl, AtLoc, RParenLoc);
}
bool Sema::CheckMessageArgumentTypes(Expr **Args, unsigned NumArgs,
Selector Sel, ObjCMethodDecl *Method,
bool isClassMessage,
SourceLocation lbrac, SourceLocation rbrac,
QualType &ReturnType) {
if (!Method) {
// Apply default argument promotion as for (C99 6.5.2.2p6).
for (unsigned i = 0; i != NumArgs; i++)
DefaultArgumentPromotion(Args[i]);
unsigned DiagID = isClassMessage ? diag::warn_class_method_not_found :
diag::warn_inst_method_not_found;
Diag(lbrac, DiagID)
<< Sel << isClassMessage << SourceRange(lbrac, rbrac);
ReturnType = Context.getObjCIdType();
return false;
}
ReturnType = Method->getResultType();
unsigned NumNamedArgs = Sel.getNumArgs();
assert(NumArgs >= NumNamedArgs && "Too few arguments for selector!");
bool anyIncompatibleArgs = false;
for (unsigned i = 0; i < NumNamedArgs; i++) {
Expr *argExpr = Args[i];
assert(argExpr && "CheckMessageArgumentTypes(): missing expression");
QualType lhsType = Method->param_begin()[i]->getType();
QualType rhsType = argExpr->getType();
// If necessary, apply function/array conversion. C99 6.7.5.3p[7,8].
if (lhsType->isArrayType())
lhsType = Context.getArrayDecayedType(lhsType);
else if (lhsType->isFunctionType())
lhsType = Context.getPointerType(lhsType);
AssignConvertType Result =
CheckSingleAssignmentConstraints(lhsType, argExpr);
if (Args[i] != argExpr) // The expression was converted.
Args[i] = argExpr; // Make sure we store the converted expression.
anyIncompatibleArgs |=
DiagnoseAssignmentResult(Result, argExpr->getLocStart(), lhsType, rhsType,
argExpr, "sending");
}
// Promote additional arguments to variadic methods.
if (Method->isVariadic()) {
for (unsigned i = NumNamedArgs; i < NumArgs; ++i)
DefaultVariadicArgumentPromotion(Args[i], VariadicMethod);
} else {
// Check for extra arguments to non-variadic methods.
if (NumArgs != NumNamedArgs) {
Diag(Args[NumNamedArgs]->getLocStart(),
diag::err_typecheck_call_too_many_args)
<< 2 /*method*/ << Method->getSourceRange()
<< SourceRange(Args[NumNamedArgs]->getLocStart(),
Args[NumArgs-1]->getLocEnd());
}
}
return anyIncompatibleArgs;
}
bool Sema::isSelfExpr(Expr *RExpr) {
if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(RExpr))
if (DRE->getDecl()->getIdentifier() == &Context.Idents.get("self"))
return true;
return false;
}
// Helper method for ActOnClassMethod/ActOnInstanceMethod.
// Will search "local" class/category implementations for a method decl.
// If failed, then we search in class's root for an instance method.
// Returns 0 if no method is found.
ObjCMethodDecl *Sema::LookupPrivateClassMethod(Selector Sel,
ObjCInterfaceDecl *ClassDecl) {
ObjCMethodDecl *Method = 0;
// lookup in class and all superclasses
while (ClassDecl && !Method) {
if (ObjCImplementationDecl *ImpDecl =
ObjCImplementations[ClassDecl->getIdentifier()])
Method = ImpDecl->getClassMethod(Sel);
// Look through local category implementations associated with the class.
if (!Method) {
for (unsigned i = 0; i < ObjCCategoryImpls.size() && !Method; i++) {
if (ObjCCategoryImpls[i]->getClassInterface() == ClassDecl)
Method = ObjCCategoryImpls[i]->getClassMethod(Sel);
}
}
// Before we give up, check if the selector is an instance method.
// But only in the root. This matches gcc's behaviour and what the
// runtime expects.
if (!Method && !ClassDecl->getSuperClass()) {
Method = ClassDecl->lookupInstanceMethod(Sel);
// Look through local category implementations associated
// with the root class.
if (!Method)
Method = LookupPrivateInstanceMethod(Sel, ClassDecl);
}
ClassDecl = ClassDecl->getSuperClass();
}
return Method;
}
ObjCMethodDecl *Sema::LookupPrivateInstanceMethod(Selector Sel,
ObjCInterfaceDecl *ClassDecl) {
ObjCMethodDecl *Method = 0;
while (ClassDecl && !Method) {
// If we have implementations in scope, check "private" methods.
if (ObjCImplementationDecl *ImpDecl =
ObjCImplementations[ClassDecl->getIdentifier()])
Method = ImpDecl->getInstanceMethod(Sel);
// Look through local category implementations associated with the class.
if (!Method) {
for (unsigned i = 0; i < ObjCCategoryImpls.size() && !Method; i++) {
if (ObjCCategoryImpls[i]->getClassInterface() == ClassDecl)
Method = ObjCCategoryImpls[i]->getInstanceMethod(Sel);
}
}
ClassDecl = ClassDecl->getSuperClass();
}
return Method;
}
Action::OwningExprResult Sema::ActOnClassPropertyRefExpr(
IdentifierInfo &receiverName,
IdentifierInfo &propertyName,
SourceLocation &receiverNameLoc,
SourceLocation &propertyNameLoc) {
ObjCInterfaceDecl *IFace = getObjCInterfaceDecl(&receiverName);
// Search for a declared property first.
Selector Sel = PP.getSelectorTable().getNullarySelector(&propertyName);
ObjCMethodDecl *Getter = IFace->lookupClassMethod(Sel);
// If this reference is in an @implementation, check for 'private' methods.
if (!Getter)
if (ObjCMethodDecl *CurMeth = getCurMethodDecl())
if (ObjCInterfaceDecl *ClassDecl = CurMeth->getClassInterface())
if (ObjCImplementationDecl *ImpDecl =
ObjCImplementations[ClassDecl->getIdentifier()])
Getter = ImpDecl->getClassMethod(Sel);
if (Getter) {
// FIXME: refactor/share with ActOnMemberReference().
// Check if we can reference this property.
if (DiagnoseUseOfDecl(Getter, propertyNameLoc))
return ExprError();
}
// Look for the matching setter, in case it is needed.
Selector SetterSel =
SelectorTable::constructSetterName(PP.getIdentifierTable(),
PP.getSelectorTable(), &propertyName);
ObjCMethodDecl *Setter = IFace->lookupClassMethod(SetterSel);
if (!Setter) {
// If this reference is in an @implementation, also check for 'private'
// methods.
if (ObjCMethodDecl *CurMeth = getCurMethodDecl())
if (ObjCInterfaceDecl *ClassDecl = CurMeth->getClassInterface())
if (ObjCImplementationDecl *ImpDecl =
ObjCImplementations[ClassDecl->getIdentifier()])
Setter = ImpDecl->getClassMethod(SetterSel);
}
// Look through local category implementations associated with the class.
if (!Setter) {
for (unsigned i = 0; i < ObjCCategoryImpls.size() && !Setter; i++) {
if (ObjCCategoryImpls[i]->getClassInterface() == IFace)
Setter = ObjCCategoryImpls[i]->getClassMethod(SetterSel);
}
}
if (Setter && DiagnoseUseOfDecl(Setter, propertyNameLoc))
return ExprError();
if (Getter || Setter) {
QualType PType;
if (Getter)
PType = Getter->getResultType();
else {
for (ObjCMethodDecl::param_iterator PI = Setter->param_begin(),
E = Setter->param_end(); PI != E; ++PI)
PType = (*PI)->getType();
}
return Owned(new (Context) ObjCKVCRefExpr(Getter, PType, Setter,
propertyNameLoc, IFace, receiverNameLoc));
}
return ExprError(Diag(propertyNameLoc, diag::err_property_not_found)
<< &propertyName << Context.getObjCInterfaceType(IFace));
}
// ActOnClassMessage - used for both unary and keyword messages.
// ArgExprs is optional - if it is present, the number of expressions
// is obtained from Sel.getNumArgs().
Sema::ExprResult Sema::ActOnClassMessage(
Scope *S,
IdentifierInfo *receiverName, Selector Sel,
SourceLocation lbrac, SourceLocation receiverLoc,
SourceLocation selectorLoc, SourceLocation rbrac,
ExprTy **Args, unsigned NumArgs)
{
assert(receiverName && "missing receiver class name");
Expr **ArgExprs = reinterpret_cast<Expr **>(Args);
ObjCInterfaceDecl* ClassDecl = 0;
bool isSuper = false;
if (receiverName->isStr("super")) {
if (getCurMethodDecl()) {
isSuper = true;
ObjCInterfaceDecl *OID = getCurMethodDecl()->getClassInterface();
if (!OID)
return Diag(lbrac, diag::error_no_super_class_message)
<< getCurMethodDecl()->getDeclName();
ClassDecl = OID->getSuperClass();
if (!ClassDecl)
return Diag(lbrac, diag::error_no_super_class) << OID->getDeclName();
if (getCurMethodDecl()->isInstanceMethod()) {
QualType superTy = Context.getObjCInterfaceType(ClassDecl);
superTy = Context.getPointerType(superTy);
ExprResult ReceiverExpr = new (Context) ObjCSuperExpr(SourceLocation(),
superTy);
// We are really in an instance method, redirect.
return ActOnInstanceMessage(ReceiverExpr.get(), Sel, lbrac,
selectorLoc, rbrac, Args, NumArgs);
}
// We are sending a message to 'super' within a class method. Do nothing,
// the receiver will pass through as 'super' (how convenient:-).
} else {
// 'super' has been used outside a method context. If a variable named
// 'super' has been declared, redirect. If not, produce a diagnostic.
NamedDecl *SuperDecl = LookupName(S, receiverName, LookupOrdinaryName);
ValueDecl *VD = dyn_cast_or_null<ValueDecl>(SuperDecl);
if (VD) {
ExprResult ReceiverExpr = new (Context) DeclRefExpr(VD, VD->getType(),
receiverLoc);
// We are really in an instance method, redirect.
return ActOnInstanceMessage(ReceiverExpr.get(), Sel, lbrac,
selectorLoc, rbrac, Args, NumArgs);
}
return Diag(receiverLoc, diag::err_undeclared_var_use) << receiverName;
}
} else
ClassDecl = getObjCInterfaceDecl(receiverName);
// The following code allows for the following GCC-ism:
//
// typedef XCElementDisplayRect XCElementGraphicsRect;
//
// @implementation XCRASlice
// - whatever { // Note that XCElementGraphicsRect is a typedef name.
// _sGraphicsDelegate =[[XCElementGraphicsRect alloc] init];
// }
//
// If necessary, the following lookup could move to getObjCInterfaceDecl().
if (!ClassDecl) {
NamedDecl *IDecl = LookupName(TUScope, receiverName, LookupOrdinaryName);
if (TypedefDecl *OCTD = dyn_cast_or_null<TypedefDecl>(IDecl)) {
const ObjCInterfaceType *OCIT;
OCIT = OCTD->getUnderlyingType()->getAsObjCInterfaceType();
if (!OCIT) {
Diag(receiverLoc, diag::err_invalid_receiver_to_message);
return true;
}
ClassDecl = OCIT->getDecl();
}
}
assert(ClassDecl && "missing interface declaration");
ObjCMethodDecl *Method = 0;
QualType returnType;
Method = ClassDecl->lookupClassMethod(Sel);
// If we have an implementation in scope, check "private" methods.
if (!Method)
Method = LookupPrivateClassMethod(Sel, ClassDecl);
if (Method && DiagnoseUseOfDecl(Method, receiverLoc))
return true;
if (CheckMessageArgumentTypes(ArgExprs, NumArgs, Sel, Method, true,
lbrac, rbrac, returnType))
return true;
// If we have the ObjCInterfaceDecl* for the class that is receiving
// the message, use that to construct the ObjCMessageExpr. Otherwise
// pass on the IdentifierInfo* for the class.
// FIXME: need to do a better job handling 'super' usage within a class
// For now, we simply pass the "super" identifier through (which isn't
// consistent with instance methods.
if (isSuper)
return new (Context) ObjCMessageExpr(receiverName, Sel, returnType, Method,
lbrac, rbrac, ArgExprs, NumArgs);
else
return new (Context) ObjCMessageExpr(ClassDecl, Sel, returnType, Method,
lbrac, rbrac, ArgExprs, NumArgs);
}
// ActOnInstanceMessage - used for both unary and keyword messages.
// ArgExprs is optional - if it is present, the number of expressions
// is obtained from Sel.getNumArgs().
Sema::ExprResult Sema::ActOnInstanceMessage(ExprTy *receiver, Selector Sel,
SourceLocation lbrac,
SourceLocation receiverLoc,
SourceLocation rbrac,
ExprTy **Args, unsigned NumArgs) {
assert(receiver && "missing receiver expression");
Expr **ArgExprs = reinterpret_cast<Expr **>(Args);
Expr *RExpr = static_cast<Expr *>(receiver);
QualType returnType;
QualType ReceiverCType =
Context.getCanonicalType(RExpr->getType()).getUnqualifiedType();
// Handle messages to 'super'.
if (isa<ObjCSuperExpr>(RExpr)) {
ObjCMethodDecl *Method = 0;
if (ObjCMethodDecl *CurMeth = getCurMethodDecl()) {
// If we have an interface in scope, check 'super' methods.
if (ObjCInterfaceDecl *ClassDecl = CurMeth->getClassInterface())
if (ObjCInterfaceDecl *SuperDecl = ClassDecl->getSuperClass()) {
Method = SuperDecl->lookupInstanceMethod(Sel);
if (!Method)
// If we have implementations in scope, check "private" methods.
Method = LookupPrivateInstanceMethod(Sel, SuperDecl);
}
}
if (Method && DiagnoseUseOfDecl(Method, receiverLoc))
return true;
if (CheckMessageArgumentTypes(ArgExprs, NumArgs, Sel, Method, false,
lbrac, rbrac, returnType))
return true;
return new (Context) ObjCMessageExpr(RExpr, Sel, returnType, Method, lbrac,
rbrac, ArgExprs, NumArgs);
}
// Handle messages to id.
if (ReceiverCType == Context.getCanonicalType(Context.getObjCIdType()) ||
ReceiverCType->isBlockPointerType()) {
ObjCMethodDecl *Method = LookupInstanceMethodInGlobalPool(
Sel, SourceRange(lbrac,rbrac));
if (!Method)
Method = FactoryMethodPool[Sel].Method;
if (CheckMessageArgumentTypes(ArgExprs, NumArgs, Sel, Method, false,
lbrac, rbrac, returnType))
return true;
return new (Context) ObjCMessageExpr(RExpr, Sel, returnType, Method, lbrac,
rbrac, ArgExprs, NumArgs);
}
// Handle messages to Class.
if (ReceiverCType == Context.getCanonicalType(Context.getObjCClassType())) {
ObjCMethodDecl *Method = 0;
if (ObjCMethodDecl *CurMeth = getCurMethodDecl()) {
if (ObjCInterfaceDecl *ClassDecl = CurMeth->getClassInterface()) {
// First check the public methods in the class interface.
Method = ClassDecl->lookupClassMethod(Sel);
if (!Method)
Method = LookupPrivateClassMethod(Sel, ClassDecl);
}
if (Method && DiagnoseUseOfDecl(Method, receiverLoc))
return true;
}
if (!Method) {
// If not messaging 'self', look for any factory method named 'Sel'.
if (!isSelfExpr(RExpr)) {
Method = FactoryMethodPool[Sel].Method;
if (!Method) {
Method = LookupInstanceMethodInGlobalPool(
Sel, SourceRange(lbrac,rbrac));
}
}
}
if (CheckMessageArgumentTypes(ArgExprs, NumArgs, Sel, Method, false,
lbrac, rbrac, returnType))
return true;
return new (Context) ObjCMessageExpr(RExpr, Sel, returnType, Method, lbrac,
rbrac, ArgExprs, NumArgs);
}
ObjCMethodDecl *Method = 0;
ObjCInterfaceDecl* ClassDecl = 0;
// We allow sending a message to a qualified ID ("id<foo>"), which is ok as
// long as one of the protocols implements the selector (if not, warn).
if (ObjCQualifiedIdType *QIT = dyn_cast<ObjCQualifiedIdType>(ReceiverCType)) {
// Search protocols for instance methods.
for (unsigned i = 0; i < QIT->getNumProtocols(); i++) {
ObjCProtocolDecl *PDecl = QIT->getProtocols(i);
if (PDecl && (Method = PDecl->lookupInstanceMethod(Sel)))
break;
}
} else if (const ObjCInterfaceType *OCIType =
ReceiverCType->getAsPointerToObjCInterfaceType()) {
// We allow sending a message to a pointer to an interface (an object).
ClassDecl = OCIType->getDecl();
// FIXME: consider using LookupInstanceMethodInGlobalPool, since it will be
// faster than the following method (which can do *many* linear searches).
// The idea is to add class info to InstanceMethodPool.
Method = ClassDecl->lookupInstanceMethod(Sel);
if (!Method) {
// Search protocol qualifiers.
for (ObjCQualifiedInterfaceType::qual_iterator QI = OCIType->qual_begin(),
E = OCIType->qual_end(); QI != E; ++QI) {
if ((Method = (*QI)->lookupInstanceMethod(Sel)))
break;
}
}
if (!Method) {
// If we have implementations in scope, check "private" methods.
Method = LookupPrivateInstanceMethod(Sel, ClassDecl);
if (!Method && !isSelfExpr(RExpr)) {
// If we still haven't found a method, look in the global pool. This
// behavior isn't very desirable, however we need it for GCC
// compatibility. FIXME: should we deviate??
if (OCIType->qual_empty()) {
Method = LookupInstanceMethodInGlobalPool(
Sel, SourceRange(lbrac,rbrac));
if (Method && !OCIType->getDecl()->isForwardDecl())
Diag(lbrac, diag::warn_maynot_respond)
<< OCIType->getDecl()->getIdentifier()->getName() << Sel;
}
}
}
if (Method && DiagnoseUseOfDecl(Method, receiverLoc))
return true;
} else if (!Context.getObjCIdType().isNull() &&
(ReceiverCType->isPointerType() ||
(ReceiverCType->isIntegerType() &&
ReceiverCType->isScalarType()))) {
// Implicitly convert integers and pointers to 'id' but emit a warning.
Diag(lbrac, diag::warn_bad_receiver_type)
<< RExpr->getType() << RExpr->getSourceRange();
ImpCastExprToType(RExpr, Context.getObjCIdType());
} else {
// Reject other random receiver types (e.g. structs).
Diag(lbrac, diag::err_bad_receiver_type)
<< RExpr->getType() << RExpr->getSourceRange();
return true;
}
if (CheckMessageArgumentTypes(ArgExprs, NumArgs, Sel, Method, false,
lbrac, rbrac, returnType))
return true;
return new (Context) ObjCMessageExpr(RExpr, Sel, returnType, Method, lbrac,
rbrac, ArgExprs, NumArgs);
}
//===----------------------------------------------------------------------===//
// ObjCQualifiedIdTypesAreCompatible - Compatibility testing for qualified id's.
//===----------------------------------------------------------------------===//
/// ProtocolCompatibleWithProtocol - return 'true' if 'lProto' is in the
/// inheritance hierarchy of 'rProto'.
static bool ProtocolCompatibleWithProtocol(ObjCProtocolDecl *lProto,
ObjCProtocolDecl *rProto) {
if (lProto == rProto)
return true;
for (ObjCProtocolDecl::protocol_iterator PI = rProto->protocol_begin(),
E = rProto->protocol_end(); PI != E; ++PI)
if (ProtocolCompatibleWithProtocol(lProto, *PI))
return true;
return false;
}
/// ClassImplementsProtocol - Checks that 'lProto' protocol
/// has been implemented in IDecl class, its super class or categories (if
/// lookupCategory is true).
static bool ClassImplementsProtocol(ObjCProtocolDecl *lProto,
ObjCInterfaceDecl *IDecl,
bool lookupCategory,
bool RHSIsQualifiedID = false) {
// 1st, look up the class.
const ObjCList<ObjCProtocolDecl> &Protocols =
IDecl->getReferencedProtocols();
for (ObjCList<ObjCProtocolDecl>::iterator PI = Protocols.begin(),
E = Protocols.end(); PI != E; ++PI) {
if (ProtocolCompatibleWithProtocol(lProto, *PI))
return true;
// This is dubious and is added to be compatible with gcc.
// In gcc, it is also allowed assigning a protocol-qualified 'id'
// type to a LHS object when protocol in qualified LHS is in list
// of protocols in the rhs 'id' object. This IMO, should be a bug.
// FIXME: Treat this as an extension, and flag this as an error when
// GCC extensions are not enabled.
if (RHSIsQualifiedID && ProtocolCompatibleWithProtocol(*PI, lProto))
return true;
}
// 2nd, look up the category.
if (lookupCategory)
for (ObjCCategoryDecl *CDecl = IDecl->getCategoryList(); CDecl;
CDecl = CDecl->getNextClassCategory()) {
for (ObjCCategoryDecl::protocol_iterator PI = CDecl->protocol_begin(),
E = CDecl->protocol_end(); PI != E; ++PI)
if (ProtocolCompatibleWithProtocol(lProto, *PI))
return true;
}
// 3rd, look up the super class(s)
if (IDecl->getSuperClass())
return
ClassImplementsProtocol(lProto, IDecl->getSuperClass(), lookupCategory,
RHSIsQualifiedID);
return false;
}
/// ObjCQualifiedIdTypesAreCompatible - We know that one of lhs/rhs is an
/// ObjCQualifiedIDType.
/// FIXME: Move to ASTContext::typesAreCompatible() and friends.
bool Sema::ObjCQualifiedIdTypesAreCompatible(QualType lhs, QualType rhs,
bool compare) {
// Allow id<P..> and an 'id' or void* type in all cases.
if (const PointerType *PT = lhs->getAsPointerType()) {
QualType PointeeTy = PT->getPointeeType();
if (Context.isObjCIdStructType(PointeeTy) || PointeeTy->isVoidType())
return true;
} else if (const PointerType *PT = rhs->getAsPointerType()) {
QualType PointeeTy = PT->getPointeeType();
if (Context.isObjCIdStructType(PointeeTy) || PointeeTy->isVoidType())
return true;
}
if (const ObjCQualifiedIdType *lhsQID = lhs->getAsObjCQualifiedIdType()) {
const ObjCQualifiedIdType *rhsQID = rhs->getAsObjCQualifiedIdType();
const ObjCQualifiedInterfaceType *rhsQI = 0;
QualType rtype;
if (!rhsQID) {
// Not comparing two ObjCQualifiedIdType's?
if (!rhs->isPointerType()) return false;
rtype = rhs->getAsPointerType()->getPointeeType();
rhsQI = rtype->getAsObjCQualifiedInterfaceType();
if (rhsQI == 0) {
// If the RHS is a unqualified interface pointer "NSString*",
// make sure we check the class hierarchy.
if (const ObjCInterfaceType *IT = rtype->getAsObjCInterfaceType()) {
ObjCInterfaceDecl *rhsID = IT->getDecl();
for (unsigned i = 0; i != lhsQID->getNumProtocols(); ++i) {
// when comparing an id<P> on lhs with a static type on rhs,
// see if static class implements all of id's protocols, directly or
// through its super class and categories.
if (!ClassImplementsProtocol(lhsQID->getProtocols(i), rhsID, true))
return false;
}
return true;
}
}
}
ObjCQualifiedIdType::qual_iterator RHSProtoI, RHSProtoE;
if (rhsQI) { // We have a qualified interface (e.g. "NSObject<Proto> *").
RHSProtoI = rhsQI->qual_begin();
RHSProtoE = rhsQI->qual_end();
} else if (rhsQID) { // We have a qualified id (e.g. "id<Proto> *").
RHSProtoI = rhsQID->qual_begin();
RHSProtoE = rhsQID->qual_end();
} else {
return false;
}
for (unsigned i =0; i < lhsQID->getNumProtocols(); i++) {
ObjCProtocolDecl *lhsProto = lhsQID->getProtocols(i);
bool match = false;
// when comparing an id<P> on lhs with a static type on rhs,
// see if static class implements all of id's protocols, directly or
// through its super class and categories.
for (; RHSProtoI != RHSProtoE; ++RHSProtoI) {
ObjCProtocolDecl *rhsProto = *RHSProtoI;
if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
(compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
match = true;
break;
}
}
if (rhsQI) {
// If the RHS is a qualified interface pointer "NSString<P>*",
// make sure we check the class hierarchy.
if (const ObjCInterfaceType *IT = rtype->getAsObjCInterfaceType()) {
ObjCInterfaceDecl *rhsID = IT->getDecl();
for (unsigned i = 0; i != lhsQID->getNumProtocols(); ++i) {
// when comparing an id<P> on lhs with a static type on rhs,
// see if static class implements all of id's protocols, directly or
// through its super class and categories.
if (ClassImplementsProtocol(lhsQID->getProtocols(i), rhsID, true)) {
match = true;
break;
}
}
}
}
if (!match)
return false;
}
return true;
}
const ObjCQualifiedIdType *rhsQID = rhs->getAsObjCQualifiedIdType();
assert(rhsQID && "One of the LHS/RHS should be id<x>");
if (!lhs->isPointerType())
return false;
QualType ltype = lhs->getAsPointerType()->getPointeeType();
if (const ObjCQualifiedInterfaceType *lhsQI =
ltype->getAsObjCQualifiedInterfaceType()) {
ObjCQualifiedIdType::qual_iterator LHSProtoI = lhsQI->qual_begin();
ObjCQualifiedIdType::qual_iterator LHSProtoE = lhsQI->qual_end();
for (; LHSProtoI != LHSProtoE; ++LHSProtoI) {
bool match = false;
ObjCProtocolDecl *lhsProto = *LHSProtoI;
for (unsigned j = 0; j < rhsQID->getNumProtocols(); j++) {
ObjCProtocolDecl *rhsProto = rhsQID->getProtocols(j);
if (ProtocolCompatibleWithProtocol(lhsProto, rhsProto) ||
(compare && ProtocolCompatibleWithProtocol(rhsProto, lhsProto))) {
match = true;
break;
}
}
if (!match)
return false;
}
return true;
}
if (const ObjCInterfaceType *IT = ltype->getAsObjCInterfaceType()) {
// for static type vs. qualified 'id' type, check that class implements
// all of 'id's protocols.
ObjCInterfaceDecl *lhsID = IT->getDecl();
for (unsigned j = 0; j < rhsQID->getNumProtocols(); j++) {
ObjCProtocolDecl *rhsProto = rhsQID->getProtocols(j);
if (!ClassImplementsProtocol(rhsProto, lhsID, compare, true))
return false;
}
return true;
}
return false;
}