Preliminary support for function overloading

llvm-svn: 57909
This commit is contained in:
Douglas Gregor 2008-10-21 16:13:35 +00:00
parent 0747e7e025
commit 5251f1b283
28 changed files with 1704 additions and 64 deletions

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@ -1178,7 +1178,8 @@ Stmt *RewriteObjC::RewriteObjCForCollectionStmt(ObjCForCollectionStmt *S,
else {
DeclRefExpr *DR = cast<DeclRefExpr>(S->getElement());
elementName = DR->getDecl()->getName();
elementTypeAsString = DR->getDecl()->getType().getAsString();
elementTypeAsString
= cast<ValueDecl>(DR->getDecl())->getType().getAsString();
}
// struct __objcFastEnumerationState enumState = { 0 };

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@ -137,7 +137,8 @@ public:
QualType FloatTy, DoubleTy, LongDoubleTy;
QualType FloatComplexTy, DoubleComplexTy, LongDoubleComplexTy;
QualType VoidPtrTy;
QualType OverloadTy;
ASTContext(const LangOptions& LOpts, SourceManager &SM, TargetInfo &t,
IdentifierTable &idents, SelectorTable &sels,
unsigned size_reserve=0);

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@ -48,6 +48,7 @@ public:
CXXField,
ObjCIvar,
ObjCAtDefsField,
OverloadedFunction,
ObjCCategory,
ObjCCategoryImpl,
ObjCImplementation,
@ -178,6 +179,7 @@ public:
case EnumConstant:
case ObjCInterface:
case ObjCCompatibleAlias:
case OverloadedFunction:
case CXXField:
case CXXMethod:
case CXXClassVar:

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@ -1,4 +1,4 @@
//===-- DeclCXX.h - Classes for representing C++ declarations *- C++ -*-======//
//===-- DeclCXX.h - Classes for representing C++ declarations -*- C++ -*-=====//
//
// The LLVM Compiler Infrastructure
//
@ -15,6 +15,7 @@
#define LLVM_CLANG_AST_DECLCXX_H
#include "clang/AST/Decl.h"
#include "llvm/ADT/SmallVector.h"
namespace clang {
class CXXRecordDecl;
@ -191,6 +192,85 @@ public:
}
};
/// OverloadedFunctionDecl - An instance of this class represents a
/// set of overloaded functions. All of the functions have the same
/// name and occur within the same scope.
///
/// An OverloadedFunctionDecl has no ownership over the FunctionDecl
/// nodes it contains. Rather, the FunctionDecls are owned by the
/// enclosing scope (which also owns the OverloadedFunctionDecl
/// node). OverloadedFunctionDecl is used primarily to store a set of
/// overloaded functions for name lookup.
class OverloadedFunctionDecl : public NamedDecl {
protected:
OverloadedFunctionDecl(DeclContext *DC, IdentifierInfo *Id)
: NamedDecl(OverloadedFunction, SourceLocation(), Id) { }
/// Functions - the set of overloaded functions contained in this
/// overload set.
llvm::SmallVector<FunctionDecl *, 4> Functions;
public:
typedef llvm::SmallVector<FunctionDecl *, 4>::iterator function_iterator;
typedef llvm::SmallVector<FunctionDecl *, 4>::const_iterator
function_const_iterator;
static OverloadedFunctionDecl *Create(ASTContext &C, DeclContext *DC,
IdentifierInfo *Id);
/// addOverload - Add an overloaded function FD to this set of
/// overloaded functions.
void addOverload(FunctionDecl *FD) {
assert((!getNumFunctions() || (FD->getDeclContext() == getDeclContext())) &&
"Overloaded functions must all be in the same context");
assert(FD->getIdentifier() == getIdentifier() &&
"Overloaded functions must have the same name.");
Functions.push_back(FD);
}
function_iterator function_begin() { return Functions.begin(); }
function_iterator function_end() { return Functions.end(); }
function_const_iterator function_begin() const { return Functions.begin(); }
function_const_iterator function_end() const { return Functions.end(); }
/// getNumFunctions - the number of overloaded functions stored in
/// this set.
unsigned getNumFunctions() const { return Functions.size(); }
/// getFunction - retrieve the ith function in the overload set.
const FunctionDecl *getFunction(unsigned i) const {
assert(i < getNumFunctions() && "Illegal function #");
return Functions[i];
}
FunctionDecl *getFunction(unsigned i) {
assert(i < getNumFunctions() && "Illegal function #");
return Functions[i];
}
// getDeclContext - Get the context of these overloaded functions.
DeclContext *getDeclContext() {
assert(getNumFunctions() > 0 && "Context of an empty overload set");
return getFunction(0)->getDeclContext();
}
// Implement isa/cast/dyncast/etc.
static bool classof(const Decl *D) {
return D->getKind() == OverloadedFunction;
}
static bool classof(const OverloadedFunctionDecl *D) { return true; }
protected:
/// EmitImpl - Serialize this FunctionDecl. Called by Decl::Emit.
virtual void EmitImpl(llvm::Serializer& S) const;
/// CreateImpl - Deserialize an OverloadedFunctionDecl. Called by
/// Decl::Create.
static OverloadedFunctionDecl* CreateImpl(llvm::Deserializer& D,
ASTContext& C);
friend Decl* Decl::Create(llvm::Deserializer& D, ASTContext& C);
};
} // end namespace clang
#endif

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@ -27,6 +27,7 @@ namespace clang {
class Decl;
class IdentifierInfo;
class ParmVarDecl;
class NamedDecl;
class ValueDecl;
class BlockDecl;
@ -214,19 +215,19 @@ public:
/// DeclRefExpr - [C99 6.5.1p2] - A reference to a declared variable, function,
/// enum, etc.
class DeclRefExpr : public Expr {
ValueDecl *D;
NamedDecl *D;
SourceLocation Loc;
protected:
DeclRefExpr(StmtClass SC, ValueDecl *d, QualType t, SourceLocation l) :
DeclRefExpr(StmtClass SC, NamedDecl *d, QualType t, SourceLocation l) :
Expr(SC, t), D(d), Loc(l) {}
public:
DeclRefExpr(ValueDecl *d, QualType t, SourceLocation l) :
DeclRefExpr(NamedDecl *d, QualType t, SourceLocation l) :
Expr(DeclRefExprClass, t), D(d), Loc(l) {}
ValueDecl *getDecl() { return D; }
const ValueDecl *getDecl() const { return D; }
NamedDecl *getDecl() { return D; }
const NamedDecl *getDecl() const { return D; }
SourceLocation getLocation() const { return Loc; }
virtual SourceRange getSourceRange() const { return SourceRange(Loc); }

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@ -494,7 +494,9 @@ public:
Long,
LongLong,
Float, Double, LongDouble
Float, Double, LongDouble,
Overload // This represents the type of an overloaded function declaration.
};
private:
Kind TypeKind;

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@ -18,14 +18,14 @@
#define LLVM_CLANG_EXPRDECLBVDVAL_H
#include "clang/AST/CFG.h"
#include "clang/AST/Decl.h" // for ScopedDecl* -> NamedDecl* conversion
#include "llvm/ADT/BitVector.h"
#include "llvm/ADT/DenseMap.h"
namespace clang {
class Expr;
class ScopedDecl;
struct DeclBitVector_Types {
class Idx {
@ -49,7 +49,7 @@ struct DeclBitVector_Types {
class AnalysisDataTy {
public:
typedef llvm::DenseMap<const ScopedDecl*, unsigned > DMapTy;
typedef llvm::DenseMap<const NamedDecl*, unsigned > DMapTy;
typedef DMapTy::const_iterator decl_iterator;
protected:
@ -61,16 +61,16 @@ struct DeclBitVector_Types {
AnalysisDataTy() : NDecls(0) {}
virtual ~AnalysisDataTy() {}
bool isTracked(const ScopedDecl* SD) { return DMap.find(SD) != DMap.end(); }
bool isTracked(const NamedDecl* SD) { return DMap.find(SD) != DMap.end(); }
Idx getIdx(const ScopedDecl* SD) const {
Idx getIdx(const NamedDecl* SD) const {
DMapTy::const_iterator I = DMap.find(SD);
return I == DMap.end() ? Idx() : Idx(I->second);
}
unsigned getNumDecls() const { return NDecls; }
void Register(const ScopedDecl* SD) {
void Register(const NamedDecl* SD) {
if (!isTracked(SD)) DMap[SD] = NDecls++;
}

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@ -37,7 +37,8 @@ class CFGRecStmtDeclVisitor : public CFGRecStmtVisitor<ImplClass> {
public:
void VisitDeclRefExpr(DeclRefExpr* DR) {
for (ScopedDecl* D = DR->getDecl(); D != NULL; D = D->getNextDeclarator())
for (ScopedDecl* D = dyn_cast<ScopedDecl>(DR->getDecl()); D != NULL;
D = D->getNextDeclarator())
static_cast<ImplClass*>(this)->VisitScopedDecl(D);
}

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@ -800,6 +800,20 @@ DIAG(err_previous_use, ERROR,
DIAG(err_first_label, ERROR,
"first label is here")
// C++ Overloading Semantic Analysis.
DIAG(err_ovl_diff_return_type, ERROR,
"functions that differ only in their return type cannot be overloaded")
DIAG(err_ovl_static_nonstatic_member, ERROR,
"static and non-static member functions with the same parameter types cannot be overloaded")
DIAG(err_ovl_no_viable_function_in_call, ERROR,
"no matching function for call to '%0'.")
DIAG(err_ovl_no_viable_function_in_call_with_cands, ERROR,
"no matching function for call to '%0'; candidates are:")
DIAG(err_ovl_ambiguous_call, ERROR,
"call to '%0' is ambiguous; candidates are:")
DIAG(err_ovl_candidate, NOTE,
"candidate function")
DIAG(err_unexpected_typedef, ERROR,
"unexpected type name '%0': expected expression")
DIAG(err_unexpected_namespace, ERROR,

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@ -182,11 +182,14 @@ void ASTContext::InitBuiltinTypes() {
// C++ 3.9.1p5
InitBuiltinType(WCharTy, BuiltinType::WChar);
// Placeholder type for functions.
InitBuiltinType(OverloadTy, BuiltinType::Overload);
// C99 6.2.5p11.
FloatComplexTy = getComplexType(FloatTy);
DoubleComplexTy = getComplexType(DoubleTy);
LongDoubleComplexTy = getComplexType(LongDoubleTy);
BuiltinVaListType = QualType();
ObjCIdType = QualType();
IdStructType = 0;

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@ -31,6 +31,7 @@ static unsigned nCXXSUC = 0;
static unsigned nEnumConst = 0;
static unsigned nEnumDecls = 0;
static unsigned nNamespaces = 0;
static unsigned nOverFuncs = 0;
static unsigned nTypedef = 0;
static unsigned nFieldDecls = 0;
static unsigned nCXXFieldDecls = 0;
@ -63,6 +64,7 @@ const char *Decl::getDeclKindName() const {
switch (DeclKind) {
default: assert(0 && "Unknown decl kind!");
case Namespace: return "Namespace";
case OverloadedFunction: return "OverloadedFunction";
case Typedef: return "Typedef";
case Function: return "Function";
case Var: return "Var";
@ -93,10 +95,13 @@ void Decl::PrintStats() {
int(nFuncs+nVars+nParmVars+nFieldDecls+nSUC+nCXXFieldDecls+nCXXSUC+
nEnumDecls+nEnumConst+nTypedef+nInterfaceDecls+nClassDecls+
nMethodDecls+nProtocolDecls+nCategoryDecls+nIvarDecls+
nAtDefsFieldDecls+nNamespaces));
nAtDefsFieldDecls+nNamespaces+nOverFuncs));
fprintf(stderr, " %d namespace decls, %d each (%d bytes)\n",
nNamespaces, (int)sizeof(NamespaceDecl),
int(nNamespaces*sizeof(NamespaceDecl)));
fprintf(stderr, " %d overloaded function decls, %d each (%d bytes)\n",
nOverFuncs, (int)sizeof(OverloadedFunctionDecl),
int(nOverFuncs*sizeof(OverloadedFunctionDecl)));
fprintf(stderr, " %d function decls, %d each (%d bytes)\n",
nFuncs, (int)sizeof(FunctionDecl), int(nFuncs*sizeof(FunctionDecl)));
fprintf(stderr, " %d variable decls, %d each (%d bytes)\n",
@ -192,13 +197,15 @@ void Decl::PrintStats() {
nObjCPropertyImplDecl*sizeof(ObjCPropertyImplDecl)+
nLinkageSpecDecl*sizeof(LinkageSpecDecl)+
nFileScopeAsmDecl*sizeof(FileScopeAsmDecl)+
nNamespaces*sizeof(NamespaceDecl)));
nNamespaces*sizeof(NamespaceDecl)+
nOverFuncs*sizeof(OverloadedFunctionDecl)));
}
void Decl::addDeclKind(Kind k) {
switch (k) {
case Namespace: nNamespaces++; break;
case OverloadedFunction: nOverFuncs++; break;
case Typedef: nTypedef++; break;
case Function: nFuncs++; break;
case Var: nVars++; break;

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@ -59,3 +59,10 @@ CXXClassVarDecl *CXXClassVarDecl::Create(ASTContext &C, CXXRecordDecl *RD,
void *Mem = C.getAllocator().Allocate<CXXClassVarDecl>();
return new (Mem) CXXClassVarDecl(RD, L, Id, T, PrevDecl);
}
OverloadedFunctionDecl *
OverloadedFunctionDecl::Create(ASTContext &C, DeclContext *DC,
IdentifierInfo *Id) {
void *Mem = C.getAllocator().Allocate<OverloadedFunctionDecl>();
return new (Mem) OverloadedFunctionDecl(DC, Id);
}

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@ -13,6 +13,7 @@
#include "clang/AST/ASTContext.h"
#include "clang/AST/Decl.h"
#include "clang/AST/DeclCXX.h"
#include "clang/AST/Expr.h"
#include "llvm/Bitcode/Serialize.h"
#include "llvm/Bitcode/Deserialize.h"
@ -74,7 +75,11 @@ Decl* Decl::Create(Deserializer& D, ASTContext& C) {
case Function:
Dcl = FunctionDecl::CreateImpl(D, C);
break;
case OverloadedFunction:
Dcl = OverloadedFunctionDecl::CreateImpl(D, C);
break;
case Record:
Dcl = RecordDecl::CreateImpl(D, C);
break;
@ -454,6 +459,34 @@ BlockDecl* BlockDecl::CreateImpl(Deserializer& D, ASTContext& C) {
return 0;
}
//===----------------------------------------------------------------------===//
// OverloadedFunctionDecl Serialization.
//===----------------------------------------------------------------------===//
void OverloadedFunctionDecl::EmitImpl(Serializer& S) const {
NamedDecl::EmitInRec(S);
S.EmitInt(getNumFunctions());
for (unsigned func = 0; func < getNumFunctions(); ++func)
S.EmitPtr(Functions[func]);
}
OverloadedFunctionDecl *
OverloadedFunctionDecl::CreateImpl(Deserializer& D, ASTContext& C) {
void *Mem = C.getAllocator().Allocate<OverloadedFunctionDecl>();
OverloadedFunctionDecl* decl = new (Mem)
OverloadedFunctionDecl(0, NULL);
decl->NamedDecl::ReadInRec(D, C);
unsigned numFunctions = D.ReadInt();
decl->Functions.reserve(numFunctions);
for (unsigned func = 0; func < numFunctions; ++func)
D.ReadPtr(decl->Functions[func]);
return decl;
}
//===----------------------------------------------------------------------===//
// RecordDecl Serialization.
//===----------------------------------------------------------------------===//

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@ -522,12 +522,12 @@ DeclRefExpr* DeclRefExpr::CreateImpl(Deserializer& D, ASTContext& C) {
SourceLocation Loc = SourceLocation::ReadVal(D);
QualType T = QualType::ReadVal(D);
bool OwnsDecl = D.ReadBool();
ValueDecl* decl;
NamedDecl* decl;
if (!OwnsDecl)
D.ReadPtr(decl,false); // No backpatching.
else
decl = cast<ValueDecl>(D.ReadOwnedPtr<Decl>(C));
decl = cast<NamedDecl>(D.ReadOwnedPtr<Decl>(C));
return new DeclRefExpr(decl,T,Loc);
}

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@ -450,6 +450,7 @@ bool Type::isIntegerType() const {
BT->getKind() <= BuiltinType::LongLong;
if (const TagType *TT = dyn_cast<TagType>(CanonicalType))
// Incomplete enum types are not treated as integer types.
// FIXME: In C++, enum types are never integer types.
if (TT->getDecl()->isEnum() && TT->getDecl()->isDefinition())
return true;
if (const VectorType *VT = dyn_cast<VectorType>(CanonicalType))
@ -466,6 +467,7 @@ bool Type::isIntegralType() const {
if (const TagType *TT = dyn_cast<TagType>(CanonicalType))
if (TT->getDecl()->isEnum() && TT->getDecl()->isDefinition())
return true; // Complete enum types are integral.
// FIXME: In C++, enum types are never integral.
if (const ASQualType *ASQT = dyn_cast<ASQualType>(CanonicalType))
return ASQT->getBaseType()->isIntegralType();
return false;
@ -697,6 +699,7 @@ const char *BuiltinType::getName() const {
case Double: return "double";
case LongDouble: return "long double";
case WChar: return "wchar_t";
case Overload: return "<overloaded function type>";
}
}

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@ -299,9 +299,9 @@ Store BasicStoreManager::getInitialStore() {
Store St = VBFactory.GetEmptyMap().getRoot();
for (LVDataTy::decl_iterator I=D.begin_decl(), E=D.end_decl(); I != E; ++I) {
ScopedDecl* SD = const_cast<ScopedDecl*>(I->first);
NamedDecl* ND = const_cast<NamedDecl*>(I->first);
if (VarDecl* VD = dyn_cast<VarDecl>(SD)) {
if (VarDecl* VD = dyn_cast<VarDecl>(ND)) {
// Punt on static variables for now.
if (VD->getStorageClass() == VarDecl::Static)
continue;

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@ -823,7 +823,7 @@ void GRExprEngine::VisitDeclRefExpr(DeclRefExpr* Ex, NodeTy* Pred, NodeSet& Dst,
const GRState* St = GetState(Pred);
const ValueDecl* D = Ex->getDecl();
const NamedDecl* D = Ex->getDecl();
if (const VarDecl* VD = dyn_cast<VarDecl>(D)) {

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@ -118,9 +118,9 @@ Store RegionStoreManager::getInitialStore() {
Store St = RBFactory.GetEmptyMap().getRoot();
for (LVDataTy::decl_iterator I=D.begin_decl(), E=D.end_decl(); I != E; ++I) {
ScopedDecl* SD = const_cast<ScopedDecl*>(I->first);
NamedDecl* ND = const_cast<NamedDecl*>(I->first);
if (VarDecl* VD = dyn_cast<VarDecl>(SD)) {
if (VarDecl* VD = dyn_cast<VarDecl>(ND)) {
// Punt on static variables for now.
if (VD->getStorageClass() == VarDecl::Static)
continue;

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@ -371,7 +371,7 @@ public:
}
llvm::Constant *VisitDeclRefExpr(DeclRefExpr *E) {
const ValueDecl *Decl = E->getDecl();
const NamedDecl *Decl = E->getDecl();
if (const EnumConstantDecl *EC = dyn_cast<EnumConstantDecl>(Decl))
return llvm::ConstantInt::get(EC->getInitVal());
assert(0 && "Unsupported decl ref type!");
@ -769,7 +769,7 @@ public:
return C;
}
case Expr::DeclRefExprClass: {
ValueDecl *Decl = cast<DeclRefExpr>(E)->getDecl();
NamedDecl *Decl = cast<DeclRefExpr>(E)->getDecl();
if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(Decl))
return CGM.GetAddrOfFunction(FD);
if (const VarDecl* VD = dyn_cast<VarDecl>(Decl)) {

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@ -57,7 +57,9 @@ DeclContext *IdentifierResolver::LookupContext::getContext(Decl *D) {
if (EnumConstantDecl *EnumD = dyn_cast<EnumConstantDecl>(D)) {
Ctx = EnumD->getDeclContext()->getParent();
} else if (ScopedDecl *SD = dyn_cast<ScopedDecl>(D))
Ctx = SD->getDeclContext();
Ctx = SD->getDeclContext();
else if (OverloadedFunctionDecl *Ovl = dyn_cast<OverloadedFunctionDecl>(D))
Ctx = Ovl->getDeclContext();
else
return TUCtx();

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@ -17,6 +17,7 @@
#include "IdentifierResolver.h"
#include "CXXFieldCollector.h"
#include "SemaOverload.h"
#include "clang/Parse/Action.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/DenseSet.h"
@ -361,7 +362,46 @@ private:
VarDecl *MergeVarDecl(VarDecl *New, Decl *Old);
FunctionDecl *MergeCXXFunctionDecl(FunctionDecl *New, FunctionDecl *Old);
void CheckForFileScopedRedefinitions(Scope *S, VarDecl *VD);
/// C++ Overloading.
bool IsOverload(FunctionDecl *New, Decl* OldD,
OverloadedFunctionDecl::function_iterator &MatchedDecl);
ImplicitConversionSequence TryCopyInitialization(Expr* From, QualType ToType);
bool IsIntegralPromotion(Expr *From, QualType FromType, QualType ToType);
bool IsFloatingPointPromotion(QualType FromType, QualType ToType);
bool IsPointerConversion(Expr *From, QualType FromType, QualType ToType,
QualType& ConvertedType);
ImplicitConversionSequence::CompareKind
CompareImplicitConversionSequences(const ImplicitConversionSequence& ICS1,
const ImplicitConversionSequence& ICS2);
ImplicitConversionSequence::CompareKind
CompareStandardConversionSequences(const StandardConversionSequence& SCS1,
const StandardConversionSequence& SCS2);
/// OverloadingResult - Capture the result of performing overload
/// resolution.
enum OverloadingResult {
OR_Success, ///< Overload resolution succeeded.
OR_No_Viable_Function, ///< No viable function found.
OR_Ambiguous ///< Ambiguous candidates found.
};
void AddOverloadCandidate(FunctionDecl *Function,
Expr **Args, unsigned NumArgs,
OverloadCandidateSet& CandidateSet);
void AddOverloadCandidates(OverloadedFunctionDecl *Ovl,
Expr **Args, unsigned NumArgs,
OverloadCandidateSet& CandidateSet);
bool isBetterOverloadCandidate(const OverloadCandidate& Cand1,
const OverloadCandidate& Cand2);
OverloadingResult BestViableFunction(OverloadCandidateSet& CandidateSet,
OverloadCandidateSet::iterator& Best);
void PrintOverloadCandidates(OverloadCandidateSet& CandidateSet,
bool OnlyViable);
/// Helpers for dealing with function parameters
bool CheckParmsForFunctionDef(FunctionDecl *FD);
void CheckCXXDefaultArguments(FunctionDecl *FD);

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@ -93,9 +93,43 @@ void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) {
// so swap the order on the shadowed declaration chain.
IdResolver.AddShadowedDecl(TD, *I);
return;
}
} else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
// We are pushing the name of a function, which might be an
// overloaded name.
IdentifierResolver::iterator
I = IdResolver.begin(FD->getIdentifier(),
FD->getDeclContext(), false/*LookInParentCtx*/);
if (I != IdResolver.end() &&
IdResolver.isDeclInScope(*I, FD->getDeclContext(), S) &&
(isa<OverloadedFunctionDecl>(*I) || isa<FunctionDecl>(*I))) {
// There is already a declaration with the same name in the same
// scope. It must be a function or an overloaded function.
OverloadedFunctionDecl* Ovl = dyn_cast<OverloadedFunctionDecl>(*I);
if (!Ovl) {
// We haven't yet overloaded this function. Take the existing
// FunctionDecl and put it into an OverloadedFunctionDecl.
Ovl = OverloadedFunctionDecl::Create(Context,
FD->getDeclContext(),
FD->getIdentifier());
Ovl->addOverload(dyn_cast<FunctionDecl>(*I));
// Remove the name binding to the existing FunctionDecl...
IdResolver.RemoveDecl(*I);
// ... and put the OverloadedFunctionDecl in its place.
IdResolver.AddDecl(Ovl);
}
// We have an OverloadedFunctionDecl. Add the new FunctionDecl
// to its list of overloads.
Ovl->addOverload(FD);
return;
}
}
IdResolver.AddDecl(D);
}
@ -320,9 +354,17 @@ static void MergeAttributes(Decl *New, Decl *Old) {
/// declarator D which has the same name and scope as a previous
/// declaration 'Old'. Figure out how to resolve this situation,
/// merging decls or emitting diagnostics as appropriate.
/// Redeclaration will be set true if thisNew is a redeclaration OldD.
/// Redeclaration will be set true if this New is a redeclaration OldD.
///
/// In C++, New and Old must be declarations that are not
/// overloaded. Use IsOverload to determine whether New and Old are
/// overloaded, and to select the Old declaration that New should be
/// merged with.
FunctionDecl *
Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) {
assert(!isa<OverloadedFunctionDecl>(OldD) &&
"Cannot merge with an overloaded function declaration");
Redeclaration = false;
// Verify the old decl was also a function.
FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD);
@ -332,17 +374,59 @@ Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) {
Diag(OldD->getLocation(), diag::err_previous_definition);
return New;
}
// Determine whether the previous declaration was a definition,
// implicit declaration, or a declaration.
diag::kind PrevDiag;
if (Old->isThisDeclarationADefinition())
PrevDiag = diag::err_previous_definition;
else if (Old->isImplicit())
PrevDiag = diag::err_previous_implicit_declaration;
else
PrevDiag = diag::err_previous_declaration;
QualType OldQType = Context.getCanonicalType(Old->getType());
QualType NewQType = Context.getCanonicalType(New->getType());
// C++ [dcl.fct]p3:
// All declarations for a function shall agree exactly in both the
// return type and the parameter-type-list.
if (getLangOptions().CPlusPlus && OldQType == NewQType) {
MergeAttributes(New, Old);
Redeclaration = true;
return MergeCXXFunctionDecl(New, Old);
if (getLangOptions().CPlusPlus) {
// (C++98 13.1p2):
// Certain function declarations cannot be overloaded:
// -- Function declarations that differ only in the return type
// cannot be overloaded.
QualType OldReturnType
= cast<FunctionType>(OldQType.getTypePtr())->getResultType();
QualType NewReturnType
= cast<FunctionType>(NewQType.getTypePtr())->getResultType();
if (OldReturnType != NewReturnType) {
Diag(New->getLocation(), diag::err_ovl_diff_return_type);
Diag(Old->getLocation(), PrevDiag);
return New;
}
const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old);
const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New);
if (OldMethod && NewMethod) {
// -- Member function declarations with the same name and the
// same parameter types cannot be overloaded if any of them
// is a static member function declaration.
if (OldMethod->isStatic() || NewMethod->isStatic()) {
Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member);
Diag(Old->getLocation(), PrevDiag);
return New;
}
}
// (C++98 8.3.5p3):
// All declarations for a function shall agree exactly in both the
// return type and the parameter-type-list.
if (OldQType == NewQType) {
// We have a redeclaration.
MergeAttributes(New, Old);
Redeclaration = true;
return MergeCXXFunctionDecl(New, Old);
}
// Fall through for conflicting redeclarations and redefinitions.
}
// C: Function types need to be compatible, not identical. This handles
@ -356,13 +440,6 @@ Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD, bool &Redeclaration) {
// A function that has already been declared has been redeclared or defined
// with a different type- show appropriate diagnostic
diag::kind PrevDiag;
if (Old->isThisDeclarationADefinition())
PrevDiag = diag::err_previous_definition;
else if (Old->isImplicit())
PrevDiag = diag::err_previous_implicit_declaration;
else
PrevDiag = diag::err_previous_declaration;
// TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope.
// TODO: This is totally simplistic. It should handle merging functions
@ -717,10 +794,49 @@ Sema::ActOnDeclarator(Scope *S, Declarator &D, DeclTy *lastDecl) {
if (PrevDecl &&
(!getLangOptions().CPlusPlus||isDeclInScope(PrevDecl, CurContext, S))) {
bool Redeclaration = false;
NewFD = MergeFunctionDecl(NewFD, PrevDecl, Redeclaration);
if (NewFD == 0) return 0;
if (Redeclaration) {
NewFD->setPreviousDeclaration(cast<FunctionDecl>(PrevDecl));
// If C++, determine whether NewFD is an overload of PrevDecl or
// a declaration that requires merging. If it's an overload,
// there's no more work to do here; we'll just add the new
// function to the scope.
OverloadedFunctionDecl::function_iterator MatchedDecl;
if (!getLangOptions().CPlusPlus ||
!IsOverload(NewFD, PrevDecl, MatchedDecl)) {
Decl *OldDecl = PrevDecl;
// If PrevDecl was an overloaded function, extract the
// FunctionDecl that matched.
if (isa<OverloadedFunctionDecl>(PrevDecl))
OldDecl = *MatchedDecl;
// NewFD and PrevDecl represent declarations that need to be
// merged.
NewFD = MergeFunctionDecl(NewFD, OldDecl, Redeclaration);
if (NewFD == 0) return 0;
if (Redeclaration) {
NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl));
if (OldDecl == PrevDecl) {
// Remove the name binding for the previous
// declaration. We'll add the binding back later, but then
// it will refer to the new declaration (which will
// contain more information).
IdResolver.RemoveDecl(cast<NamedDecl>(PrevDecl));
} else {
// We need to update the OverloadedFunctionDecl with the
// latest declaration of this function, so that name
// lookup will always refer to the latest declaration of
// this function.
*MatchedDecl = NewFD;
// Add the redeclaration to the current scope, since we'll
// be skipping PushOnScopeChains.
S->AddDecl(NewFD);
return NewFD;
}
}
}
}
New = NewFD;

View File

@ -19,6 +19,7 @@
#include "clang/Basic/Diagnostic.h"
#include "clang/Parse/DeclSpec.h"
#include "llvm/Support/Compiler.h"
#include <algorithm> // for std::equal
using namespace clang;
@ -58,7 +59,7 @@ namespace {
/// determine whether this declaration can be used in the default
/// argument expression.
bool CheckDefaultArgumentVisitor::VisitDeclRefExpr(DeclRefExpr *DRE) {
ValueDecl *Decl = DRE->getDecl();
NamedDecl *Decl = DRE->getDecl();
if (ParmVarDecl *Param = dyn_cast<ParmVarDecl>(Decl)) {
// C++ [dcl.fct.default]p9
// Default arguments are evaluated each time the function is

View File

@ -418,6 +418,9 @@ Sema::ExprResult Sema::ActOnIdentifierExpr(Scope *S, SourceLocation Loc,
return Diag(Loc, diag::err_unexpected_namespace, II.getName());
// Make the DeclRefExpr or BlockDeclRefExpr for the decl.
if (OverloadedFunctionDecl *Ovl = dyn_cast<OverloadedFunctionDecl>(D))
return new DeclRefExpr(Ovl, Context.OverloadTy, Loc);
ValueDecl *VD = cast<ValueDecl>(D);
// check if referencing an identifier with __attribute__((deprecated)).
@ -1036,16 +1039,67 @@ ActOnCallExpr(ExprTy *fn, SourceLocation LParenLoc,
Expr **Args = reinterpret_cast<Expr**>(args);
assert(Fn && "no function call expression");
FunctionDecl *FDecl = NULL;
OverloadedFunctionDecl *Ovl = NULL;
// If we're directly calling a function or a set of overloaded
// functions, get the appropriate declaration.
{
DeclRefExpr *DRExpr = NULL;
if (ImplicitCastExpr *IcExpr = dyn_cast<ImplicitCastExpr>(Fn))
DRExpr = dyn_cast<DeclRefExpr>(IcExpr->getSubExpr());
else
DRExpr = dyn_cast<DeclRefExpr>(Fn);
if (DRExpr) {
FDecl = dyn_cast<FunctionDecl>(DRExpr->getDecl());
Ovl = dyn_cast<OverloadedFunctionDecl>(DRExpr->getDecl());
}
}
// If we have a set of overloaded functions, perform overload
// resolution to pick the function.
if (Ovl) {
OverloadCandidateSet CandidateSet;
OverloadCandidateSet::iterator Best;
AddOverloadCandidates(Ovl, Args, NumArgs, CandidateSet);
switch (BestViableFunction(CandidateSet, Best)) {
case OR_Success:
{
// Success! Let the remainder of this function build a call to
// the function selected by overload resolution.
FDecl = Best->Function;
Expr *NewFn = new DeclRefExpr(FDecl, FDecl->getType(),
Fn->getSourceRange().getBegin());
delete Fn;
Fn = NewFn;
}
break;
case OR_No_Viable_Function:
if (CandidateSet.empty())
Diag(Fn->getSourceRange().getBegin(),
diag::err_ovl_no_viable_function_in_call, Ovl->getName(),
Fn->getSourceRange());
else {
Diag(Fn->getSourceRange().getBegin(),
diag::err_ovl_no_viable_function_in_call_with_cands,
Ovl->getName(), Fn->getSourceRange());
PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/false);
}
return true;
case OR_Ambiguous:
Diag(Fn->getSourceRange().getBegin(),
diag::err_ovl_ambiguous_call, Ovl->getName(),
Fn->getSourceRange());
PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true);
return true;
}
}
// Promote the function operand.
UsualUnaryConversions(Fn);
// If we're directly calling a function, get the declaration for
// that function.
if (ImplicitCastExpr *IcExpr = dyn_cast<ImplicitCastExpr>(Fn))
if (DeclRefExpr *DRExpr = dyn_cast<DeclRefExpr>(IcExpr->getSubExpr()))
FDecl = dyn_cast<FunctionDecl>(DRExpr->getDecl());
// Make the call expr early, before semantic checks. This guarantees cleanup
// of arguments and function on error.
llvm::OwningPtr<CallExpr> TheCall(new CallExpr(Fn, Args, NumArgs,
@ -2338,7 +2392,7 @@ QualType Sema::CheckIncrementDecrementOperand(Expr *op, SourceLocation OpLoc) {
/// - *(x + 1) -> x, if x is an array
/// - &"123"[2] -> 0
/// - & __real__ x -> x
static ValueDecl *getPrimaryDecl(Expr *E) {
static NamedDecl *getPrimaryDecl(Expr *E) {
switch (E->getStmtClass()) {
case Stmt::DeclRefExprClass:
return cast<DeclRefExpr>(E)->getDecl();
@ -2351,7 +2405,8 @@ static ValueDecl *getPrimaryDecl(Expr *E) {
case Stmt::ArraySubscriptExprClass: {
// &X[4] and &4[X] refers to X if X is not a pointer.
ValueDecl *VD = getPrimaryDecl(cast<ArraySubscriptExpr>(E)->getBase());
NamedDecl *D = getPrimaryDecl(cast<ArraySubscriptExpr>(E)->getBase());
ValueDecl *VD = dyn_cast<ValueDecl>(D);
if (!VD || VD->getType()->isPointerType())
return 0;
else
@ -2363,10 +2418,13 @@ static ValueDecl *getPrimaryDecl(Expr *E) {
switch(UO->getOpcode()) {
case UnaryOperator::Deref: {
// *(X + 1) refers to X if X is not a pointer.
ValueDecl *VD = getPrimaryDecl(UO->getSubExpr());
if (!VD || VD->getType()->isPointerType())
return 0;
return VD;
if (NamedDecl *D = getPrimaryDecl(UO->getSubExpr())) {
ValueDecl *VD = dyn_cast<ValueDecl>(D);
if (!VD || VD->getType()->isPointerType())
return 0;
return VD;
}
return 0;
}
case UnaryOperator::Real:
case UnaryOperator::Imag:
@ -2420,7 +2478,7 @@ QualType Sema::CheckAddressOfOperand(Expr *op, SourceLocation OpLoc) {
// Technically, there should be a check for array subscript
// expressions here, but the result of one is always an lvalue anyway.
}
ValueDecl *dcl = getPrimaryDecl(op);
NamedDecl *dcl = getPrimaryDecl(op);
Expr::isLvalueResult lval = op->isLvalue(Context);
if (lval != Expr::LV_Valid) { // C99 6.5.3.2p1

View File

@ -0,0 +1,903 @@
//===--- SemaOverload.cpp - C++ Overloading ---------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file provides Sema routines for C++ overloading.
//
//===----------------------------------------------------------------------===//
#include "Sema.h"
#include "clang/Basic/Diagnostic.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/Expr.h"
#include "llvm/Support/Compiler.h"
#include <algorithm>
namespace clang {
/// GetConversionCategory - Retrieve the implicit conversion
/// category corresponding to the given implicit conversion kind.
ImplicitConversionCategory
GetConversionCategory(ImplicitConversionKind Kind) {
static const ImplicitConversionCategory
Category[(int)ICK_Num_Conversion_Kinds] = {
ICC_Identity,
ICC_Lvalue_Transformation,
ICC_Lvalue_Transformation,
ICC_Lvalue_Transformation,
ICC_Qualification_Adjustment,
ICC_Promotion,
ICC_Promotion,
ICC_Conversion,
ICC_Conversion,
ICC_Conversion,
ICC_Conversion,
ICC_Conversion,
ICC_Conversion
};
return Category[(int)Kind];
}
/// GetConversionRank - Retrieve the implicit conversion rank
/// corresponding to the given implicit conversion kind.
ImplicitConversionRank GetConversionRank(ImplicitConversionKind Kind) {
static const ImplicitConversionRank
Rank[(int)ICK_Num_Conversion_Kinds] = {
ICR_Exact_Match,
ICR_Exact_Match,
ICR_Exact_Match,
ICR_Exact_Match,
ICR_Exact_Match,
ICR_Promotion,
ICR_Promotion,
ICR_Conversion,
ICR_Conversion,
ICR_Conversion,
ICR_Conversion,
ICR_Conversion,
ICR_Conversion
};
return Rank[(int)Kind];
}
/// GetImplicitConversionName - Return the name of this kind of
/// implicit conversion.
const char* GetImplicitConversionName(ImplicitConversionKind Kind) {
static const char* Name[(int)ICK_Num_Conversion_Kinds] = {
"No conversion",
"Lvalue-to-rvalue",
"Array-to-pointer",
"Function-to-pointer",
"Qualification",
"Integral promotion",
"Floating point promotion",
"Integral conversion",
"Floating conversion",
"Floating-integral conversion",
"Pointer conversion",
"Pointer-to-member conversion",
"Boolean conversion"
};
return Name[Kind];
}
/// getRank - Retrieve the rank of this standard conversion sequence
/// (C++ 13.3.3.1.1p3). The rank is the largest rank of each of the
/// implicit conversions.
ImplicitConversionRank StandardConversionSequence::getRank() const {
ImplicitConversionRank Rank = ICR_Exact_Match;
if (GetConversionRank(First) > Rank)
Rank = GetConversionRank(First);
if (GetConversionRank(Second) > Rank)
Rank = GetConversionRank(Second);
if (GetConversionRank(Third) > Rank)
Rank = GetConversionRank(Third);
return Rank;
}
/// isPointerConversionToBool - Determines whether this conversion is
/// a conversion of a pointer or pointer-to-member to bool. This is
/// used as part of the ranking of standard conversion sequences
/// (C++ 13.3.3.2p4).
bool StandardConversionSequence::isPointerConversionToBool() const
{
QualType FromType = QualType::getFromOpaquePtr(FromTypePtr);
QualType ToType = QualType::getFromOpaquePtr(ToTypePtr);
// Note that FromType has not necessarily been transformed by the
// array-to-pointer or function-to-pointer implicit conversions, so
// check for their presence as well as checking whether FromType is
// a pointer.
if (ToType->isBooleanType() &&
(FromType->isPointerType() ||
First == ICK_Array_To_Pointer || First == ICK_Function_To_Pointer))
return true;
return false;
}
/// DebugPrint - Print this standard conversion sequence to standard
/// error. Useful for debugging overloading issues.
void StandardConversionSequence::DebugPrint() const {
bool PrintedSomething = false;
if (First != ICK_Identity) {
fprintf(stderr, "%s", GetImplicitConversionName(First));
PrintedSomething = true;
}
if (Second != ICK_Identity) {
if (PrintedSomething) {
fprintf(stderr, " -> ");
}
fprintf(stderr, "%s", GetImplicitConversionName(Second));
PrintedSomething = true;
}
if (Third != ICK_Identity) {
if (PrintedSomething) {
fprintf(stderr, " -> ");
}
fprintf(stderr, "%s", GetImplicitConversionName(Third));
PrintedSomething = true;
}
if (!PrintedSomething) {
fprintf(stderr, "No conversions required");
}
}
/// DebugPrint - Print this user-defined conversion sequence to standard
/// error. Useful for debugging overloading issues.
void UserDefinedConversionSequence::DebugPrint() const {
if (Before.First || Before.Second || Before.Third) {
Before.DebugPrint();
fprintf(stderr, " -> ");
}
fprintf(stderr, "'%s'", ConversionFunction->getName());
if (After.First || After.Second || After.Third) {
fprintf(stderr, " -> ");
After.DebugPrint();
}
}
/// DebugPrint - Print this implicit conversion sequence to standard
/// error. Useful for debugging overloading issues.
void ImplicitConversionSequence::DebugPrint() const {
switch (ConversionKind) {
case StandardConversion:
fprintf(stderr, "Standard conversion: ");
Standard.DebugPrint();
break;
case UserDefinedConversion:
fprintf(stderr, "User-defined conversion: ");
UserDefined.DebugPrint();
break;
case EllipsisConversion:
fprintf(stderr, "Ellipsis conversion");
break;
case BadConversion:
fprintf(stderr, "Bad conversion");
break;
}
fprintf(stderr, "\n");
}
// IsOverload - Determine whether the given New declaration is an
// overload of the Old declaration. This routine returns false if New
// and Old cannot be overloaded, e.g., if they are functions with the
// same signature (C++ 1.3.10) or if the Old declaration isn't a
// function (or overload set). When it does return false and Old is an
// OverloadedFunctionDecl, MatchedDecl will be set to point to the
// FunctionDecl that New cannot be overloaded with.
//
// Example: Given the following input:
//
// void f(int, float); // #1
// void f(int, int); // #2
// int f(int, int); // #3
//
// When we process #1, there is no previous declaration of "f",
// so IsOverload will not be used.
//
// When we process #2, Old is a FunctionDecl for #1. By comparing the
// parameter types, we see that #1 and #2 are overloaded (since they
// have different signatures), so this routine returns false;
// MatchedDecl is unchanged.
//
// When we process #3, Old is an OverloadedFunctionDecl containing #1
// and #2. We compare the signatures of #3 to #1 (they're overloaded,
// so we do nothing) and then #3 to #2. Since the signatures of #3 and
// #2 are identical (return types of functions are not part of the
// signature), IsOverload returns false and MatchedDecl will be set to
// point to the FunctionDecl for #2.
bool
Sema::IsOverload(FunctionDecl *New, Decl* OldD,
OverloadedFunctionDecl::function_iterator& MatchedDecl)
{
if (OverloadedFunctionDecl* Ovl = dyn_cast<OverloadedFunctionDecl>(OldD)) {
// Is this new function an overload of every function in the
// overload set?
OverloadedFunctionDecl::function_iterator Func = Ovl->function_begin(),
FuncEnd = Ovl->function_end();
for (; Func != FuncEnd; ++Func) {
if (!IsOverload(New, *Func, MatchedDecl)) {
MatchedDecl = Func;
return false;
}
}
// This function overloads every function in the overload set.
return true;
} else if (FunctionDecl* Old = dyn_cast<FunctionDecl>(OldD)) {
// Is the function New an overload of the function Old?
QualType OldQType = Context.getCanonicalType(Old->getType());
QualType NewQType = Context.getCanonicalType(New->getType());
// Compare the signatures (C++ 1.3.10) of the two functions to
// determine whether they are overloads. If we find any mismatch
// in the signature, they are overloads.
// If either of these functions is a K&R-style function (no
// prototype), then we consider them to have matching signatures.
if (isa<FunctionTypeNoProto>(OldQType.getTypePtr()) ||
isa<FunctionTypeNoProto>(NewQType.getTypePtr()))
return false;
FunctionTypeProto* OldType = cast<FunctionTypeProto>(OldQType.getTypePtr());
FunctionTypeProto* NewType = cast<FunctionTypeProto>(NewQType.getTypePtr());
// The signature of a function includes the types of its
// parameters (C++ 1.3.10), which includes the presence or absence
// of the ellipsis; see C++ DR 357).
if (OldQType != NewQType &&
(OldType->getNumArgs() != NewType->getNumArgs() ||
OldType->isVariadic() != NewType->isVariadic() ||
!std::equal(OldType->arg_type_begin(), OldType->arg_type_end(),
NewType->arg_type_begin())))
return true;
// If the function is a class member, its signature includes the
// cv-qualifiers (if any) on the function itself.
//
// As part of this, also check whether one of the member functions
// is static, in which case they are not overloads (C++
// 13.1p2). While not part of the definition of the signature,
// this check is important to determine whether these functions
// can be overloaded.
CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old);
CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New);
if (OldMethod && NewMethod &&
!OldMethod->isStatic() && !NewMethod->isStatic() &&
OldQType.getCVRQualifiers() != NewQType.getCVRQualifiers())
return true;
// The signatures match; this is not an overload.
return false;
} else {
// (C++ 13p1):
// Only function declarations can be overloaded; object and type
// declarations cannot be overloaded.
return false;
}
}
/// TryCopyInitialization - Attempt to copy-initialize a value of the
/// given type (ToType) from the given expression (Expr), as one would
/// do when copy-initializing a function parameter. This function
/// returns an implicit conversion sequence that can be used to
/// perform the initialization. Given
///
/// void f(float f);
/// void g(int i) { f(i); }
///
/// this routine would produce an implicit conversion sequence to
/// describe the initialization of f from i, which will be a standard
/// conversion sequence containing an lvalue-to-rvalue conversion (C++
/// 4.1) followed by a floating-integral conversion (C++ 4.9).
//
/// Note that this routine only determines how the conversion can be
/// performed; it does not actually perform the conversion. As such,
/// it will not produce any diagnostics if no conversion is available,
/// but will instead return an implicit conversion sequence of kind
/// "BadConversion".
ImplicitConversionSequence
Sema::TryCopyInitialization(Expr* From, QualType ToType)
{
ImplicitConversionSequence ICS;
QualType FromType = From->getType();
// Standard conversions (C++ 4)
ICS.ConversionKind = ImplicitConversionSequence::StandardConversion;
ICS.Standard.Deprecated = false;
ICS.Standard.FromTypePtr = FromType.getAsOpaquePtr();
// The first conversion can be an lvalue-to-rvalue conversion,
// array-to-pointer conversion, or function-to-pointer conversion
// (C++ 4p1).
// Lvalue-to-rvalue conversion (C++ 4.1):
// An lvalue (3.10) of a non-function, non-array type T can be
// converted to an rvalue.
Expr::isLvalueResult argIsLvalue = From->isLvalue(Context);
if (argIsLvalue == Expr::LV_Valid &&
!FromType->isFunctionType() && !FromType->isArrayType()) {
ICS.Standard.First = ICK_Lvalue_To_Rvalue;
// If T is a non-class type, the type of the rvalue is the
// cv-unqualified version of T. Otherwise, the type of the rvalue
// is T (C++ 4.1p1).
if (!FromType->isRecordType())
FromType = FromType.getUnqualifiedType();
}
// Array-to-pointer conversion (C++ 4.2)
else if (FromType->isArrayType()) {
ICS.Standard.First = ICK_Array_To_Pointer;
// An lvalue or rvalue of type "array of N T" or "array of unknown
// bound of T" can be converted to an rvalue of type "pointer to
// T" (C++ 4.2p1).
FromType = Context.getArrayDecayedType(FromType);
if (IsStringLiteralToNonConstPointerConversion(From, ToType)) {
// This conversion is deprecated. (C++ D.4).
ICS.Standard.Deprecated = true;
// For the purpose of ranking in overload resolution
// (13.3.3.1.1), this conversion is considered an
// array-to-pointer conversion followed by a qualification
// conversion (4.4). (C++ 4.2p2)
ICS.Standard.Second = ICK_Identity;
ICS.Standard.Third = ICK_Qualification;
ICS.Standard.ToTypePtr = ToType.getAsOpaquePtr();
return ICS;
}
}
// Function-to-pointer conversion (C++ 4.3).
else if (FromType->isFunctionType() && argIsLvalue == Expr::LV_Valid) {
ICS.Standard.First = ICK_Function_To_Pointer;
// An lvalue of function type T can be converted to an rvalue of
// type "pointer to T." The result is a pointer to the
// function. (C++ 4.3p1).
FromType = Context.getPointerType(FromType);
// FIXME: Deal with overloaded functions here (C++ 4.3p2).
}
// We don't require any conversions for the first step.
else {
ICS.Standard.First = ICK_Identity;
}
// The second conversion can be an integral promotion, floating
// point promotion, integral conversion, floating point conversion,
// floating-integral conversion, pointer conversion,
// pointer-to-member conversion, or boolean conversion (C++ 4p1).
if (Context.getCanonicalType(FromType).getUnqualifiedType() ==
Context.getCanonicalType(ToType).getUnqualifiedType()) {
// The unqualified versions of the types are the same: there's no
// conversion to do.
ICS.Standard.Second = ICK_Identity;
}
// Integral promotion (C++ 4.5).
else if (IsIntegralPromotion(From, FromType, ToType)) {
ICS.Standard.Second = ICK_Integral_Promotion;
FromType = ToType.getUnqualifiedType();
}
// Floating point promotion (C++ 4.6).
else if (IsFloatingPointPromotion(FromType, ToType)) {
ICS.Standard.Second = ICK_Floating_Promotion;
FromType = ToType.getUnqualifiedType();
}
// Integral conversions (C++ 4.7).
else if ((FromType->isIntegralType() || FromType->isEnumeralType()) &&
(ToType->isIntegralType() || ToType->isEnumeralType())) {
ICS.Standard.Second = ICK_Integral_Conversion;
FromType = ToType.getUnqualifiedType();
}
// Floating point conversions (C++ 4.8).
else if (FromType->isFloatingType() && ToType->isFloatingType()) {
ICS.Standard.Second = ICK_Floating_Conversion;
FromType = ToType.getUnqualifiedType();
}
// Floating-integral conversions (C++ 4.9).
else if ((FromType->isFloatingType() &&
ToType->isIntegralType() && !ToType->isBooleanType()) ||
((FromType->isIntegralType() || FromType->isEnumeralType()) &&
ToType->isFloatingType())) {
ICS.Standard.Second = ICK_Floating_Integral;
FromType = ToType.getUnqualifiedType();
}
// Pointer conversions (C++ 4.10).
else if (IsPointerConversion(From, FromType, ToType, FromType))
ICS.Standard.Second = ICK_Pointer_Conversion;
// FIXME: Pointer to member conversions (4.11).
// Boolean conversions (C++ 4.12).
// FIXME: pointer-to-member type
else if (ToType->isBooleanType() &&
(FromType->isArithmeticType() ||
FromType->isEnumeralType() ||
FromType->isPointerType())) {
ICS.Standard.Second = ICK_Boolean_Conversion;
FromType = Context.BoolTy;
} else {
// No second conversion required.
ICS.Standard.Second = ICK_Identity;
}
// The third conversion can be a qualification conversion (C++ 4p1).
// FIXME: CheckPointerTypesForAssignment isn't the right way to
// determine whether we have a qualification conversion.
if (Context.getCanonicalType(FromType) != Context.getCanonicalType(ToType)
&& CheckPointerTypesForAssignment(ToType, FromType) == Compatible) {
ICS.Standard.Third = ICK_Qualification;
FromType = ToType;
} else {
// No conversion required
ICS.Standard.Third = ICK_Identity;
}
// If we have not converted the argument type to the parameter type,
// this is a bad conversion sequence.
if (Context.getCanonicalType(FromType) != Context.getCanonicalType(ToType))
ICS.ConversionKind = ImplicitConversionSequence::BadConversion;
ICS.Standard.ToTypePtr = FromType.getAsOpaquePtr();
return ICS;
}
/// IsIntegralPromotion - Determines whether the conversion from the
/// expression From (whose potentially-adjusted type is FromType) to
/// ToType is an integral promotion (C++ 4.5). If so, returns true and
/// sets PromotedType to the promoted type.
bool Sema::IsIntegralPromotion(Expr *From, QualType FromType, QualType ToType)
{
const BuiltinType *To = ToType->getAsBuiltinType();
// An rvalue of type char, signed char, unsigned char, short int, or
// unsigned short int can be converted to an rvalue of type int if
// int can represent all the values of the source type; otherwise,
// the source rvalue can be converted to an rvalue of type unsigned
// int (C++ 4.5p1).
if (FromType->isPromotableIntegerType() && !FromType->isBooleanType() && To) {
if (// We can promote any signed, promotable integer type to an int
(FromType->isSignedIntegerType() ||
// We can promote any unsigned integer type whose size is
// less than int to an int.
(!FromType->isSignedIntegerType() &&
Context.getTypeSize(FromType) < Context.getTypeSize(ToType))))
return To->getKind() == BuiltinType::Int;
return To->getKind() == BuiltinType::UInt;
}
// An rvalue of type wchar_t (3.9.1) or an enumeration type (7.2)
// can be converted to an rvalue of the first of the following types
// that can represent all the values of its underlying type: int,
// unsigned int, long, or unsigned long (C++ 4.5p2).
if ((FromType->isEnumeralType() || FromType->isWideCharType())
&& ToType->isIntegerType()) {
// Determine whether the type we're converting from is signed or
// unsigned.
bool FromIsSigned;
uint64_t FromSize = Context.getTypeSize(FromType);
if (const EnumType *FromEnumType = FromType->getAsEnumType()) {
QualType UnderlyingType = FromEnumType->getDecl()->getIntegerType();
FromIsSigned = UnderlyingType->isSignedIntegerType();
} else {
// FIXME: Is wchar_t signed or unsigned? We assume it's signed for now.
FromIsSigned = true;
}
// The types we'll try to promote to, in the appropriate
// order. Try each of these types.
QualType PromoteTypes[4] = {
Context.IntTy, Context.UnsignedIntTy,
Context.LongTy, Context.UnsignedLongTy
};
for (int Idx = 0; Idx < 0; ++Idx) {
uint64_t ToSize = Context.getTypeSize(PromoteTypes[Idx]);
if (FromSize < ToSize ||
(FromSize == ToSize &&
FromIsSigned == PromoteTypes[Idx]->isSignedIntegerType())) {
// We found the type that we can promote to. If this is the
// type we wanted, we have a promotion. Otherwise, no
// promotion.
return Context.getCanonicalType(FromType).getUnqualifiedType()
== Context.getCanonicalType(PromoteTypes[Idx]).getUnqualifiedType();
}
}
}
// An rvalue for an integral bit-field (9.6) can be converted to an
// rvalue of type int if int can represent all the values of the
// bit-field; otherwise, it can be converted to unsigned int if
// unsigned int can represent all the values of the bit-field. If
// the bit-field is larger yet, no integral promotion applies to
// it. If the bit-field has an enumerated type, it is treated as any
// other value of that type for promotion purposes (C++ 4.5p3).
if (MemberExpr *MemRef = dyn_cast<MemberExpr>(From)) {
using llvm::APSInt;
FieldDecl *MemberDecl = MemRef->getMemberDecl();
APSInt BitWidth;
if (MemberDecl->isBitField() &&
FromType->isIntegralType() && !FromType->isEnumeralType() &&
From->isIntegerConstantExpr(BitWidth, Context)) {
APSInt ToSize(Context.getTypeSize(ToType));
// Are we promoting to an int from a bitfield that fits in an int?
if (BitWidth < ToSize ||
(FromType->isSignedIntegerType() && BitWidth <= ToSize))
return To->getKind() == BuiltinType::Int;
// Are we promoting to an unsigned int from an unsigned bitfield
// that fits into an unsigned int?
if (FromType->isUnsignedIntegerType() && BitWidth <= ToSize)
return To->getKind() == BuiltinType::UInt;
return false;
}
}
// An rvalue of type bool can be converted to an rvalue of type int,
// with false becoming zero and true becoming one (C++ 4.5p4).
if (FromType->isBooleanType() && To && To->getKind() == BuiltinType::Int)
return true;
return false;
}
/// IsFloatingPointPromotion - Determines whether the conversion from
/// FromType to ToType is a floating point promotion (C++ 4.6). If so,
/// returns true and sets PromotedType to the promoted type.
bool Sema::IsFloatingPointPromotion(QualType FromType, QualType ToType)
{
/// An rvalue of type float can be converted to an rvalue of type
/// double. (C++ 4.6p1).
if (const BuiltinType *FromBuiltin = FromType->getAsBuiltinType())
if (const BuiltinType *ToBuiltin = ToType->getAsBuiltinType())
if (FromBuiltin->getKind() == BuiltinType::Float &&
ToBuiltin->getKind() == BuiltinType::Double)
return true;
return false;
}
/// IsPointerConversion - Determines whether the conversion of the
/// expression From, which has the (possibly adjusted) type FromType,
/// can be converted to the type ToType via a pointer conversion (C++
/// 4.10). If so, returns true and places the converted type (that
/// might differ from ToType in its cv-qualifiers at some level) into
/// ConvertedType.
bool Sema::IsPointerConversion(Expr *From, QualType FromType, QualType ToType,
QualType& ConvertedType)
{
const PointerType* ToTypePtr = ToType->getAsPointerType();
if (!ToTypePtr)
return false;
// A null pointer constant can be converted to a pointer type (C++ 4.10p1).
if (From->isNullPointerConstant(Context)) {
ConvertedType = ToType;
return true;
}
// An rvalue of type "pointer to cv T," where T is an object type,
// can be converted to an rvalue of type "pointer to cv void" (C++
// 4.10p2).
if (FromType->isPointerType() &&
FromType->getAsPointerType()->getPointeeType()->isObjectType() &&
ToTypePtr->getPointeeType()->isVoidType()) {
// We need to produce a pointer to cv void, where cv is the same
// set of cv-qualifiers as we had on the incoming pointee type.
QualType toPointee = ToTypePtr->getPointeeType();
unsigned Quals = Context.getCanonicalType(FromType)->getAsPointerType()
->getPointeeType().getCVRQualifiers();
if (Context.getCanonicalType(ToTypePtr->getPointeeType()).getCVRQualifiers()
== Quals) {
// ToType is exactly the type we want. Use it.
ConvertedType = ToType;
} else {
// Build a new type with the right qualifiers.
ConvertedType
= Context.getPointerType(Context.VoidTy.getQualifiedType(Quals));
}
return true;
}
// FIXME: An rvalue of type "pointer to cv D," where D is a class
// type, can be converted to an rvalue of type "pointer to cv B,"
// where B is a base class (clause 10) of D (C++ 4.10p3).
return false;
}
/// CompareImplicitConversionSequences - Compare two implicit
/// conversion sequences to determine whether one is better than the
/// other or if they are indistinguishable (C++ 13.3.3.2).
ImplicitConversionSequence::CompareKind
Sema::CompareImplicitConversionSequences(const ImplicitConversionSequence& ICS1,
const ImplicitConversionSequence& ICS2)
{
// (C++ 13.3.3.2p2): When comparing the basic forms of implicit
// conversion sequences (as defined in 13.3.3.1)
// -- a standard conversion sequence (13.3.3.1.1) is a better
// conversion sequence than a user-defined conversion sequence or
// an ellipsis conversion sequence, and
// -- a user-defined conversion sequence (13.3.3.1.2) is a better
// conversion sequence than an ellipsis conversion sequence
// (13.3.3.1.3).
//
if (ICS1.ConversionKind < ICS2.ConversionKind)
return ImplicitConversionSequence::Better;
else if (ICS2.ConversionKind < ICS1.ConversionKind)
return ImplicitConversionSequence::Worse;
// Two implicit conversion sequences of the same form are
// indistinguishable conversion sequences unless one of the
// following rules apply: (C++ 13.3.3.2p3):
if (ICS1.ConversionKind == ImplicitConversionSequence::StandardConversion)
return CompareStandardConversionSequences(ICS1.Standard, ICS2.Standard);
else if (ICS1.ConversionKind ==
ImplicitConversionSequence::UserDefinedConversion) {
// User-defined conversion sequence U1 is a better conversion
// sequence than another user-defined conversion sequence U2 if
// they contain the same user-defined conversion function or
// constructor and if the second standard conversion sequence of
// U1 is better than the second standard conversion sequence of
// U2 (C++ 13.3.3.2p3).
if (ICS1.UserDefined.ConversionFunction ==
ICS2.UserDefined.ConversionFunction)
return CompareStandardConversionSequences(ICS1.UserDefined.After,
ICS2.UserDefined.After);
}
return ImplicitConversionSequence::Indistinguishable;
}
/// CompareStandardConversionSequences - Compare two standard
/// conversion sequences to determine whether one is better than the
/// other or if they are indistinguishable (C++ 13.3.3.2p3).
ImplicitConversionSequence::CompareKind
Sema::CompareStandardConversionSequences(const StandardConversionSequence& SCS1,
const StandardConversionSequence& SCS2)
{
// Standard conversion sequence S1 is a better conversion sequence
// than standard conversion sequence S2 if (C++ 13.3.3.2p3):
// -- S1 is a proper subsequence of S2 (comparing the conversion
// sequences in the canonical form defined by 13.3.3.1.1,
// excluding any Lvalue Transformation; the identity conversion
// sequence is considered to be a subsequence of any
// non-identity conversion sequence) or, if not that,
if (SCS1.Second == SCS2.Second && SCS1.Third == SCS2.Third)
// Neither is a proper subsequence of the other. Do nothing.
;
else if ((SCS1.Second == ICK_Identity && SCS1.Third == SCS2.Third) ||
(SCS1.Third == ICK_Identity && SCS1.Second == SCS2.Second) ||
(SCS1.Second == ICK_Identity &&
SCS1.Third == ICK_Identity))
// SCS1 is a proper subsequence of SCS2.
return ImplicitConversionSequence::Better;
else if ((SCS2.Second == ICK_Identity && SCS2.Third == SCS1.Third) ||
(SCS2.Third == ICK_Identity && SCS2.Second == SCS1.Second) ||
(SCS2.Second == ICK_Identity &&
SCS2.Third == ICK_Identity))
// SCS2 is a proper subsequence of SCS1.
return ImplicitConversionSequence::Worse;
// -- the rank of S1 is better than the rank of S2 (by the rules
// defined below), or, if not that,
ImplicitConversionRank Rank1 = SCS1.getRank();
ImplicitConversionRank Rank2 = SCS2.getRank();
if (Rank1 < Rank2)
return ImplicitConversionSequence::Better;
else if (Rank2 < Rank1)
return ImplicitConversionSequence::Worse;
else {
// (C++ 13.3.3.2p4): Two conversion sequences with the same rank
// are indistinguishable unless one of the following rules
// applies:
// A conversion that is not a conversion of a pointer, or
// pointer to member, to bool is better than another conversion
// that is such a conversion.
if (SCS1.isPointerConversionToBool() != SCS2.isPointerConversionToBool())
return SCS2.isPointerConversionToBool()
? ImplicitConversionSequence::Better
: ImplicitConversionSequence::Worse;
// FIXME: The other bullets in (C++ 13.3.3.2p4) require support
// for derived classes.
}
// FIXME: Handle comparison by qualifications.
// FIXME: Handle comparison of reference bindings.
return ImplicitConversionSequence::Indistinguishable;
}
/// AddOverloadCandidate - Adds the given function to the set of
/// candidate functions, using the given function call arguments.
void
Sema::AddOverloadCandidate(FunctionDecl *Function,
Expr **Args, unsigned NumArgs,
OverloadCandidateSet& CandidateSet)
{
const FunctionTypeProto* Proto
= dyn_cast<FunctionTypeProto>(Function->getType()->getAsFunctionType());
assert(Proto && "Functions without a prototype cannot be overloaded");
// Add this candidate
CandidateSet.push_back(OverloadCandidate());
OverloadCandidate& Candidate = CandidateSet.back();
Candidate.Function = Function;
unsigned NumArgsInProto = Proto->getNumArgs();
// (C++ 13.3.2p2): A candidate function having fewer than m
// parameters is viable only if it has an ellipsis in its parameter
// list (8.3.5).
if (NumArgs > NumArgsInProto && !Proto->isVariadic()) {
Candidate.Viable = false;
return;
}
// (C++ 13.3.2p2): A candidate function having more than m parameters
// is viable only if the (m+1)st parameter has a default argument
// (8.3.6). For the purposes of overload resolution, the
// parameter list is truncated on the right, so that there are
// exactly m parameters.
unsigned MinRequiredArgs = Function->getMinRequiredArguments();
if (NumArgs < MinRequiredArgs) {
// Not enough arguments.
Candidate.Viable = false;
return;
}
// Determine the implicit conversion sequences for each of the
// arguments.
Candidate.Viable = true;
Candidate.Conversions.resize(NumArgs);
for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) {
if (ArgIdx < NumArgsInProto) {
// (C++ 13.3.2p3): for F to be a viable function, there shall
// exist for each argument an implicit conversion sequence
// (13.3.3.1) that converts that argument to the corresponding
// parameter of F.
QualType ParamType = Proto->getArgType(ArgIdx);
Candidate.Conversions[ArgIdx]
= TryCopyInitialization(Args[ArgIdx], ParamType);
if (Candidate.Conversions[ArgIdx].ConversionKind
== ImplicitConversionSequence::BadConversion)
Candidate.Viable = false;
} else {
// (C++ 13.3.2p2): For the purposes of overload resolution, any
// argument for which there is no corresponding parameter is
// considered to ""match the ellipsis" (C+ 13.3.3.1.3).
Candidate.Conversions[ArgIdx].ConversionKind
= ImplicitConversionSequence::EllipsisConversion;
}
}
}
/// AddOverloadCandidates - Add all of the function overloads in Ovl
/// to the candidate set.
void
Sema::AddOverloadCandidates(OverloadedFunctionDecl *Ovl,
Expr **Args, unsigned NumArgs,
OverloadCandidateSet& CandidateSet)
{
for (OverloadedFunctionDecl::function_iterator Func = Ovl->function_begin();
Func != Ovl->function_end(); ++Func)
AddOverloadCandidate(*Func, Args, NumArgs, CandidateSet);
}
/// isBetterOverloadCandidate - Determines whether the first overload
/// candidate is a better candidate than the second (C++ 13.3.3p1).
bool
Sema::isBetterOverloadCandidate(const OverloadCandidate& Cand1,
const OverloadCandidate& Cand2)
{
// Define viable functions to be better candidates than non-viable
// functions.
if (!Cand2.Viable)
return Cand1.Viable;
else if (!Cand1.Viable)
return false;
// FIXME: Deal with the implicit object parameter for static member
// functions. (C++ 13.3.3p1).
// (C++ 13.3.3p1): a viable function F1 is defined to be a better
// function than another viable function F2 if for all arguments i,
// ICSi(F1) is not a worse conversion sequence than ICSi(F2), and
// then...
unsigned NumArgs = Cand1.Conversions.size();
assert(Cand2.Conversions.size() == NumArgs && "Overload candidate mismatch");
bool HasBetterConversion = false;
for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) {
switch (CompareImplicitConversionSequences(Cand1.Conversions[ArgIdx],
Cand2.Conversions[ArgIdx])) {
case ImplicitConversionSequence::Better:
// Cand1 has a better conversion sequence.
HasBetterConversion = true;
break;
case ImplicitConversionSequence::Worse:
// Cand1 can't be better than Cand2.
return false;
case ImplicitConversionSequence::Indistinguishable:
// Do nothing.
break;
}
}
if (HasBetterConversion)
return true;
// FIXME: Several other bullets in (C++ 13.3.3p1) need to be implemented.
return false;
}
/// BestViableFunction - Computes the best viable function (C++ 13.3.3)
/// within an overload candidate set. If overloading is successful,
/// the result will be OR_Success and Best will be set to point to the
/// best viable function within the candidate set. Otherwise, one of
/// several kinds of errors will be returned; see
/// Sema::OverloadingResult.
Sema::OverloadingResult
Sema::BestViableFunction(OverloadCandidateSet& CandidateSet,
OverloadCandidateSet::iterator& Best)
{
// Find the best viable function.
Best = CandidateSet.end();
for (OverloadCandidateSet::iterator Cand = CandidateSet.begin();
Cand != CandidateSet.end(); ++Cand) {
if (Cand->Viable) {
if (Best == CandidateSet.end() || isBetterOverloadCandidate(*Cand, *Best))
Best = Cand;
}
}
// If we didn't find any viable functions, abort.
if (Best == CandidateSet.end())
return OR_No_Viable_Function;
// Make sure that this function is better than every other viable
// function. If not, we have an ambiguity.
for (OverloadCandidateSet::iterator Cand = CandidateSet.begin();
Cand != CandidateSet.end(); ++Cand) {
if (Cand->Viable &&
Cand != Best &&
!isBetterOverloadCandidate(*Best, *Cand))
return OR_Ambiguous;
}
// Best is the best viable function.
return OR_Success;
}
/// PrintOverloadCandidates - When overload resolution fails, prints
/// diagnostic messages containing the candidates in the candidate
/// set. If OnlyViable is true, only viable candidates will be printed.
void
Sema::PrintOverloadCandidates(OverloadCandidateSet& CandidateSet,
bool OnlyViable)
{
OverloadCandidateSet::iterator Cand = CandidateSet.begin(),
LastCand = CandidateSet.end();
for (; Cand != LastCand; ++Cand) {
if (Cand->Viable ||!OnlyViable)
Diag(Cand->Function->getLocation(), diag::err_ovl_candidate);
}
}
} // end namespace clang

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//===--- Overload.h - C++ Overloading ---------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the data structures and types used in C++
// overload resolution.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CLANG_SEMA_OVERLOAD_H
#define LLVM_CLANG_SEMA_OVERLOAD_H
#include "llvm/ADT/SmallVector.h"
namespace clang {
class FunctionDecl;
/// ImplicitConversionKind - The kind of implicit conversion used to
/// convert an argument to a parameter's type. The enumerator values
/// match with Table 9 of (C++ 13.3.3.1.1) and are listed such that
/// better conversion kinds have smaller values.
enum ImplicitConversionKind {
ICK_Identity = 0, ///< Identity conversion (no conversion)
ICK_Lvalue_To_Rvalue, ///< Lvalue-to-rvalue conversion (C++ 4.1)
ICK_Array_To_Pointer, ///< Array-to-pointer conversion (C++ 4.2)
ICK_Function_To_Pointer, ///< Function-to-pointer (C++ 4.3)
ICK_Qualification, ///< Qualification conversions (C++ 4.4)
ICK_Integral_Promotion, ///< Integral promotions (C++ 4.5)
ICK_Floating_Promotion, ///< Floating point promotions (C++ 4.6)
ICK_Integral_Conversion, ///< Integral conversions (C++ 4.7)
ICK_Floating_Conversion, ///< Floating point conversions (C++ 4.8)
ICK_Floating_Integral, ///< Floating-integral conversions (C++ 4.9)
ICK_Pointer_Conversion, ///< Pointer conversions (C++ 4.10)
ICK_Pointer_Member, ///< Pointer-to-member conversions (C++ 4.11)
ICK_Boolean_Conversion, ///< Boolean conversions (C++ 4.12)
ICK_Num_Conversion_Kinds ///< The number of conversion kinds
};
/// ImplicitConversionCategory - The category of an implicit
/// conversion kind. The enumerator values match with Table 9 of
/// (C++ 13.3.3.1.1) and are listed such that better conversion
/// categories have smaller values.
enum ImplicitConversionCategory {
ICC_Identity = 0, ///< Identity
ICC_Lvalue_Transformation, ///< Lvalue transformation
ICC_Qualification_Adjustment, ///< Qualification adjustment
ICC_Promotion, ///< Promotion
ICC_Conversion ///< Conversion
};
ImplicitConversionCategory
GetConversionCategory(ImplicitConversionKind Kind);
/// ImplicitConversionRank - The rank of an implicit conversion
/// kind. The enumerator values match with Table 9 of (C++
/// 13.3.3.1.1) and are listed such that better conversion ranks
/// have smaller values.
enum ImplicitConversionRank {
ICR_Exact_Match = 0, ///< Exact Match
ICR_Promotion, ///< Promotion
ICR_Conversion ///< Conversion
};
ImplicitConversionRank GetConversionRank(ImplicitConversionKind Kind);
/// StandardConversionSequence - represents a standard conversion
/// sequence (C++ 13.3.3.1.1). A standard conversion sequence
/// contains between zero and three conversions. If a particular
/// conversion is not needed, it will be set to the identity conversion
/// (ICK_Identity). Note that the three conversions are
/// specified as separate members (rather than in an array) so that
/// we can keep the size of a standard conversion sequence to a
/// single word.
struct StandardConversionSequence {
/// First -- The first conversion can be an lvalue-to-rvalue
/// conversion, array-to-pointer conversion, or
/// function-to-pointer conversion.
ImplicitConversionKind First : 8;
/// Second - The second conversion can be an integral promotion,
/// floating point promotion, integral conversion, floating point
/// conversion, floating-integral conversion, pointer conversion,
/// pointer-to-member conversion, or boolean conversion.
ImplicitConversionKind Second : 8;
/// Third - The third conversion can be a qualification conversion.
ImplicitConversionKind Third : 8;
/// Deprecated - Whether this is a deprecated conversion, such as
/// converting a string literal to a pointer to non-const
/// character data (C++ 4.2p2).
bool Deprecated : 1;
/// FromType - The type that this conversion is converting
/// from. This is an opaque pointer for that can be translated
/// into a QualType.
void *FromTypePtr;
/// ToType - The type that this conversion is converting to. This
/// is an opaque pointer for that can be translated into a
/// QualType.
void *ToTypePtr;
ImplicitConversionRank getRank() const;
bool isPointerConversionToBool() const;
void DebugPrint() const;
};
/// UserDefinedConversionSequence - Represents a user-defined
/// conversion sequence (C++ 13.3.3.1.2).
struct UserDefinedConversionSequence {
/// Before - Represents the standard conversion that occurs before
/// the actual user-defined conversion. (C++ 13.3.3.1.2p1):
///
/// If the user-defined conversion is specified by a constructor
/// (12.3.1), the initial standard conversion sequence converts
/// the source type to the type required by the argument of the
/// constructor. If the user-defined conversion is specified by
/// a conversion function (12.3.2), the initial standard
/// conversion sequence converts the source type to the implicit
/// object parameter of the conversion function.
StandardConversionSequence Before;
/// After - Represents the standard conversion that occurs after
/// the actual user-defined conversion.
StandardConversionSequence After;
/// ConversionFunction - The function that will perform the
/// user-defined conversion.
FunctionDecl* ConversionFunction;
void DebugPrint() const;
};
/// ImplicitConversionSequence - Represents an implicit conversion
/// sequence, which may be a standard conversion sequence
// (C++ 13.3.3.1.1), user-defined conversion sequence (C++ 13.3.3.1.2),
/// or an ellipsis conversion sequence (C++ 13.3.3.1.3).
struct ImplicitConversionSequence {
/// Kind - The kind of implicit conversion sequence. BadConversion
/// specifies that there is no conversion from the source type to
/// the target type. The enumerator values are ordered such that
/// better implicit conversions have smaller values.
enum Kind {
StandardConversion = 0,
UserDefinedConversion,
EllipsisConversion,
BadConversion
};
/// ConversionKind - The kind of implicit conversion sequence.
Kind ConversionKind;
union {
/// When ConversionKind == StandardConversion, provides the
/// details of the standard conversion sequence.
StandardConversionSequence Standard;
/// When ConversionKind == UserDefinedConversion, provides the
/// details of the user-defined conversion sequence.
UserDefinedConversionSequence UserDefined;
};
// The result of a comparison between implicit conversion
// sequences. Use Sema::CompareImplicitConversionSequences to
// actually perform the comparison.
enum CompareKind {
Better,
Indistinguishable,
Worse
};
void DebugPrint() const;
};
/// OverloadCandidate - A single candidate in an overload set (C++ 13.3).
struct OverloadCandidate {
/// Function - The actual function that this candidate represents.
FunctionDecl *Function;
/// Conversions - The conversion sequences used to convert the
/// function arguments to the function parameters.
llvm::SmallVector<ImplicitConversionSequence, 4> Conversions;
/// Viable - True to indicate that this overload candidate is viable.
bool Viable;
};
/// OverloadCandidateSet - A set of overload candidates, used in C++
/// overload resolution (C++ 13.3).
typedef llvm::SmallVector<OverloadCandidate, 4> OverloadCandidateSet;
} // end namespace clang
#endif // LLVM_CLANG_SEMA_OVERLOAD_H

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// RUN: clang -fsyntax-only -pedantic -verify %s
int* f(int);
float* f(float);
void f();
void test_f(int iv, float fv) {
float* fp = f(fv);
int* ip = f(iv);
}
int* g(int, float, int); // expected-note {{ candidate function }}
float* g(int, int, int); // expected-note {{ candidate function }}
double* g(int, float, float); // expected-note {{ candidate function }}
char* g(int, float, ...); // expected-note {{ candidate function }}
void g();
void test_g(int iv, float fv) {
int* ip1 = g(iv, fv, 0);
float* fp1 = g(iv, iv, 0);
double* dp1 = g(iv, fv, fv);
char* cp1 = g(0, 0);
char* cp2 = g(0, 0, 0, iv, fv);
double* dp2 = g(0, fv, 1.5); // expected-error {{ call to 'g' is ambiguous; candidates are: }}
}
double* h(double f);
int* h(int);
void test_h(float fv, unsigned char cv) {
double* dp = h(fv);
int* ip = h(cv);
}
int* i(int);
double* i(long);
void test_i(short sv, int iv, long lv, unsigned char ucv) {
int* ip1 = i(sv);
int* ip2 = i(iv);
int* ip3 = i(ucv);
double* dp1 = i(lv);
}
int* j(void*);
double* j(bool);
void test_j(int* ip) {
int* ip1 = j(ip);
}
int* k(char*);
double* k(bool);
void test_k() {
int* ip1 = k("foo");
double* dp1 = k(L"foo");
}
int* l(wchar_t*);
double* l(bool);
void test_l() {
int* ip1 = l(L"foo");
double* dp1 = l("foo");
}
int* m(const char*);
double* m(char*);
void test_m() {
int* ip = m("foo");
}
int* n(char*);
double* n(void*);
void test_n() {
char ca[7];
int* ip1 = n(ca);
int* ip2 = n("foo");
float fa[7];
double* dp1 = n(fa);
}
enum PromotesToInt {
PromotesToIntValue = 1
};
enum PromotesToUnsignedInt {
PromotesToUnsignedIntValue = (unsigned int)-1
};
int* o(int);
double* o(unsigned int);
float* o(long);
void test_o() {
int* ip1 = o(PromotesToIntValue);
double* dp1 = o(PromotesToUnsignedIntValue);
}
int* p(int);
double* p(double);
void test_p() {
int* ip = p((short)1);
double* dp = p(1.0f);
}
struct Bits {
signed short int_bitfield : 5;
unsigned int uint_bitfield : 8;
};
int* bitfields(int, int);
float* bitfields(unsigned int, int);
void test_bitfield(Bits bits, int x) {
int* ip = bitfields(bits.int_bitfield, 0);
float* fp = bitfields(bits.uint_bitfield, 0u);
}
int* multiparm(long, int, long); // expected-note {{ candidate function }}
float* multiparm(int, int, int); // expected-note {{ candidate function }}
double* multiparm(int, int, short); // expected-note {{ candidate function }}
void test_multiparm(long lv, short sv, int iv) {
int* ip1 = multiparm(lv, iv, lv);
int* ip2 = multiparm(lv, sv, lv);
float* fp1 = multiparm(iv, iv, iv);
float* fp2 = multiparm(sv, iv, iv);
double* dp1 = multiparm(sv, sv, sv);
double* dp2 = multiparm(iv, sv, sv);
multiparm(sv, sv, lv); // expected-error {{ call to 'multiparm' is ambiguous; candidates are: }}
}

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// RUN: clang -fsyntax-only -verify %s
void f();
void f(int);
void f(int, float);
void f(int, int);
void f(int, ...);
typedef float Float;
void f(int, Float); // expected-error {{error: previous declaration is here}}
int f(int, Float); // expected-error {{error: functions that differ only in their return type cannot be overloaded}}
void g(void); // expected-error {{error: previous declaration is here}}
int g(); // expected-error {{error: functions that differ only in their return type cannot be overloaded}}
class X {
void f();
void f(int);
// FIXME: can't test this until we can handle const methods.
// void f() const;
void g(int); // expected-error {{error: previous declaration is here}}
void g(int, float); // expected-error {{error: previous declaration is here}}
int g(int, Float); // expected-error {{error: functions that differ only in their return type cannot be overloaded}}
static void g(float);
static void g(int); // expected-error {{error: static and non-static member functions with the same parameter types cannot be overloaded}}
};