llvm-project/clang/lib/AST/ExprCXX.cpp
Douglas Gregor 5d3507d39c Improve handling of initialization by constructor, by ensuring that
such initializations properly convert constructor arguments and fill
in default arguments where necessary. This also makes the ownership
model more clear.

llvm-svn: 81394
2009-09-09 23:08:42 +00:00

597 lines
24 KiB
C++

//===--- ExprCXX.cpp - (C++) Expression AST Node Implementation -----------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the subclesses of Expr class declared in ExprCXX.h
//
//===----------------------------------------------------------------------===//
#include "clang/Basic/IdentifierTable.h"
#include "clang/AST/DeclCXX.h"
#include "clang/AST/DeclTemplate.h"
#include "clang/AST/ExprCXX.h"
using namespace clang;
//===----------------------------------------------------------------------===//
// Child Iterators for iterating over subexpressions/substatements
//===----------------------------------------------------------------------===//
// CXXTypeidExpr - has child iterators if the operand is an expression
Stmt::child_iterator CXXTypeidExpr::child_begin() {
return isTypeOperand() ? child_iterator() : &Operand.Ex;
}
Stmt::child_iterator CXXTypeidExpr::child_end() {
return isTypeOperand() ? child_iterator() : &Operand.Ex+1;
}
// CXXBoolLiteralExpr
Stmt::child_iterator CXXBoolLiteralExpr::child_begin() {
return child_iterator();
}
Stmt::child_iterator CXXBoolLiteralExpr::child_end() {
return child_iterator();
}
// CXXNullPtrLiteralExpr
Stmt::child_iterator CXXNullPtrLiteralExpr::child_begin() {
return child_iterator();
}
Stmt::child_iterator CXXNullPtrLiteralExpr::child_end() {
return child_iterator();
}
// CXXThisExpr
Stmt::child_iterator CXXThisExpr::child_begin() { return child_iterator(); }
Stmt::child_iterator CXXThisExpr::child_end() { return child_iterator(); }
// CXXThrowExpr
Stmt::child_iterator CXXThrowExpr::child_begin() { return &Op; }
Stmt::child_iterator CXXThrowExpr::child_end() {
// If Op is 0, we are processing throw; which has no children.
return Op ? &Op+1 : &Op;
}
// CXXDefaultArgExpr
Stmt::child_iterator CXXDefaultArgExpr::child_begin() {
return child_iterator();
}
Stmt::child_iterator CXXDefaultArgExpr::child_end() {
return child_iterator();
}
// CXXZeroInitValueExpr
Stmt::child_iterator CXXZeroInitValueExpr::child_begin() {
return child_iterator();
}
Stmt::child_iterator CXXZeroInitValueExpr::child_end() {
return child_iterator();
}
// CXXConditionDeclExpr
Stmt::child_iterator CXXConditionDeclExpr::child_begin() {
return getVarDecl();
}
Stmt::child_iterator CXXConditionDeclExpr::child_end() {
return child_iterator();
}
// CXXNewExpr
CXXNewExpr::CXXNewExpr(bool globalNew, FunctionDecl *operatorNew,
Expr **placementArgs, unsigned numPlaceArgs,
bool parenTypeId, Expr *arraySize,
CXXConstructorDecl *constructor, bool initializer,
Expr **constructorArgs, unsigned numConsArgs,
FunctionDecl *operatorDelete, QualType ty,
SourceLocation startLoc, SourceLocation endLoc)
: Expr(CXXNewExprClass, ty, ty->isDependentType(), ty->isDependentType()),
GlobalNew(globalNew), ParenTypeId(parenTypeId),
Initializer(initializer), Array(arraySize), NumPlacementArgs(numPlaceArgs),
NumConstructorArgs(numConsArgs), OperatorNew(operatorNew),
OperatorDelete(operatorDelete), Constructor(constructor),
StartLoc(startLoc), EndLoc(endLoc) {
unsigned TotalSize = Array + NumPlacementArgs + NumConstructorArgs;
SubExprs = new Stmt*[TotalSize];
unsigned i = 0;
if (Array)
SubExprs[i++] = arraySize;
for (unsigned j = 0; j < NumPlacementArgs; ++j)
SubExprs[i++] = placementArgs[j];
for (unsigned j = 0; j < NumConstructorArgs; ++j)
SubExprs[i++] = constructorArgs[j];
assert(i == TotalSize);
}
Stmt::child_iterator CXXNewExpr::child_begin() { return &SubExprs[0]; }
Stmt::child_iterator CXXNewExpr::child_end() {
return &SubExprs[0] + Array + getNumPlacementArgs() + getNumConstructorArgs();
}
// CXXDeleteExpr
Stmt::child_iterator CXXDeleteExpr::child_begin() { return &Argument; }
Stmt::child_iterator CXXDeleteExpr::child_end() { return &Argument+1; }
// CXXPseudoDestructorExpr
Stmt::child_iterator CXXPseudoDestructorExpr::child_begin() { return &Base; }
Stmt::child_iterator CXXPseudoDestructorExpr::child_end() {
return &Base + 1;
}
// UnresolvedFunctionNameExpr
Stmt::child_iterator UnresolvedFunctionNameExpr::child_begin() {
return child_iterator();
}
Stmt::child_iterator UnresolvedFunctionNameExpr::child_end() {
return child_iterator();
}
// UnaryTypeTraitExpr
Stmt::child_iterator UnaryTypeTraitExpr::child_begin() {
return child_iterator();
}
Stmt::child_iterator UnaryTypeTraitExpr::child_end() {
return child_iterator();
}
// UnresolvedDeclRefExpr
StmtIterator UnresolvedDeclRefExpr::child_begin() {
return child_iterator();
}
StmtIterator UnresolvedDeclRefExpr::child_end() {
return child_iterator();
}
TemplateIdRefExpr::TemplateIdRefExpr(QualType T,
NestedNameSpecifier *Qualifier,
SourceRange QualifierRange,
TemplateName Template,
SourceLocation TemplateNameLoc,
SourceLocation LAngleLoc,
const TemplateArgument *TemplateArgs,
unsigned NumTemplateArgs,
SourceLocation RAngleLoc)
: Expr(TemplateIdRefExprClass, T,
(Template.isDependent() ||
TemplateSpecializationType::anyDependentTemplateArguments(
TemplateArgs, NumTemplateArgs)),
(Template.isDependent() ||
TemplateSpecializationType::anyDependentTemplateArguments(
TemplateArgs, NumTemplateArgs))),
Qualifier(Qualifier), QualifierRange(QualifierRange), Template(Template),
TemplateNameLoc(TemplateNameLoc), LAngleLoc(LAngleLoc),
RAngleLoc(RAngleLoc), NumTemplateArgs(NumTemplateArgs) {
TemplateArgument *StoredTemplateArgs
= reinterpret_cast<TemplateArgument *> (this+1);
for (unsigned I = 0; I != NumTemplateArgs; ++I)
new (StoredTemplateArgs + I) TemplateArgument(TemplateArgs[I]);
}
TemplateIdRefExpr *
TemplateIdRefExpr::Create(ASTContext &Context, QualType T,
NestedNameSpecifier *Qualifier,
SourceRange QualifierRange,
TemplateName Template, SourceLocation TemplateNameLoc,
SourceLocation LAngleLoc,
const TemplateArgument *TemplateArgs,
unsigned NumTemplateArgs, SourceLocation RAngleLoc) {
void *Mem = Context.Allocate(sizeof(TemplateIdRefExpr) +
sizeof(TemplateArgument) * NumTemplateArgs);
return new (Mem) TemplateIdRefExpr(T, Qualifier, QualifierRange, Template,
TemplateNameLoc, LAngleLoc, TemplateArgs,
NumTemplateArgs, RAngleLoc);
}
void TemplateIdRefExpr::DoDestroy(ASTContext &Context) {
const TemplateArgument *TemplateArgs = getTemplateArgs();
for (unsigned I = 0; I != NumTemplateArgs; ++I)
if (Expr *E = TemplateArgs[I].getAsExpr())
E->Destroy(Context);
this->~TemplateIdRefExpr();
Context.Deallocate(this);
}
Stmt::child_iterator TemplateIdRefExpr::child_begin() {
// FIXME: Walk the expressions in the template arguments (?)
return Stmt::child_iterator();
}
Stmt::child_iterator TemplateIdRefExpr::child_end() {
// FIXME: Walk the expressions in the template arguments (?)
return Stmt::child_iterator();
}
bool UnaryTypeTraitExpr::EvaluateTrait(ASTContext& C) const {
switch(UTT) {
default: assert(false && "Unknown type trait or not implemented");
case UTT_IsPOD: return QueriedType->isPODType();
case UTT_IsClass: // Fallthrough
case UTT_IsUnion:
if (const RecordType *Record = QueriedType->getAs<RecordType>()) {
bool Union = Record->getDecl()->isUnion();
return UTT == UTT_IsUnion ? Union : !Union;
}
return false;
case UTT_IsEnum: return QueriedType->isEnumeralType();
case UTT_IsPolymorphic:
if (const RecordType *Record = QueriedType->getAs<RecordType>()) {
// Type traits are only parsed in C++, so we've got CXXRecords.
return cast<CXXRecordDecl>(Record->getDecl())->isPolymorphic();
}
return false;
case UTT_IsAbstract:
if (const RecordType *RT = QueriedType->getAs<RecordType>())
return cast<CXXRecordDecl>(RT->getDecl())->isAbstract();
return false;
case UTT_IsEmpty:
if (const RecordType *Record = QueriedType->getAs<RecordType>()) {
return !Record->getDecl()->isUnion()
&& cast<CXXRecordDecl>(Record->getDecl())->isEmpty();
}
return false;
case UTT_HasTrivialConstructor:
// http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
// If __is_pod (type) is true then the trait is true, else if type is
// a cv class or union type (or array thereof) with a trivial default
// constructor ([class.ctor]) then the trait is true, else it is false.
if (QueriedType->isPODType())
return true;
if (const RecordType *RT =
C.getBaseElementType(QueriedType)->getAs<RecordType>())
return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialConstructor();
return false;
case UTT_HasTrivialCopy:
// http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
// If __is_pod (type) is true or type is a reference type then
// the trait is true, else if type is a cv class or union type
// with a trivial copy constructor ([class.copy]) then the trait
// is true, else it is false.
if (QueriedType->isPODType() || QueriedType->isReferenceType())
return true;
if (const RecordType *RT = QueriedType->getAs<RecordType>())
return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialCopyConstructor();
return false;
case UTT_HasTrivialAssign:
// http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
// If type is const qualified or is a reference type then the
// trait is false. Otherwise if __is_pod (type) is true then the
// trait is true, else if type is a cv class or union type with
// a trivial copy assignment ([class.copy]) then the trait is
// true, else it is false.
// Note: the const and reference restrictions are interesting,
// given that const and reference members don't prevent a class
// from having a trivial copy assignment operator (but do cause
// errors if the copy assignment operator is actually used, q.v.
// [class.copy]p12).
if (C.getBaseElementType(QueriedType).isConstQualified())
return false;
if (QueriedType->isPODType())
return true;
if (const RecordType *RT = QueriedType->getAs<RecordType>())
return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialCopyAssignment();
return false;
case UTT_HasTrivialDestructor:
// http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
// If __is_pod (type) is true or type is a reference type
// then the trait is true, else if type is a cv class or union
// type (or array thereof) with a trivial destructor
// ([class.dtor]) then the trait is true, else it is
// false.
if (QueriedType->isPODType() || QueriedType->isReferenceType())
return true;
if (const RecordType *RT =
C.getBaseElementType(QueriedType)->getAs<RecordType>())
return cast<CXXRecordDecl>(RT->getDecl())->hasTrivialDestructor();
return false;
}
}
SourceRange CXXOperatorCallExpr::getSourceRange() const {
OverloadedOperatorKind Kind = getOperator();
if (Kind == OO_PlusPlus || Kind == OO_MinusMinus) {
if (getNumArgs() == 1)
// Prefix operator
return SourceRange(getOperatorLoc(),
getArg(0)->getSourceRange().getEnd());
else
// Postfix operator
return SourceRange(getArg(0)->getSourceRange().getEnd(),
getOperatorLoc());
} else if (Kind == OO_Call) {
return SourceRange(getArg(0)->getSourceRange().getBegin(), getRParenLoc());
} else if (Kind == OO_Subscript) {
return SourceRange(getArg(0)->getSourceRange().getBegin(), getRParenLoc());
} else if (getNumArgs() == 1) {
return SourceRange(getOperatorLoc(), getArg(0)->getSourceRange().getEnd());
} else if (getNumArgs() == 2) {
return SourceRange(getArg(0)->getSourceRange().getBegin(),
getArg(1)->getSourceRange().getEnd());
} else {
return SourceRange();
}
}
Expr *CXXMemberCallExpr::getImplicitObjectArgument() {
if (MemberExpr *MemExpr = dyn_cast<MemberExpr>(getCallee()->IgnoreParens()))
return MemExpr->getBase();
// FIXME: Will eventually need to cope with member pointers.
return 0;
}
//===----------------------------------------------------------------------===//
// Named casts
//===----------------------------------------------------------------------===//
/// getCastName - Get the name of the C++ cast being used, e.g.,
/// "static_cast", "dynamic_cast", "reinterpret_cast", or
/// "const_cast". The returned pointer must not be freed.
const char *CXXNamedCastExpr::getCastName() const {
switch (getStmtClass()) {
case CXXStaticCastExprClass: return "static_cast";
case CXXDynamicCastExprClass: return "dynamic_cast";
case CXXReinterpretCastExprClass: return "reinterpret_cast";
case CXXConstCastExprClass: return "const_cast";
default: return "<invalid cast>";
}
}
CXXTemporary *CXXTemporary::Create(ASTContext &C,
const CXXDestructorDecl *Destructor) {
return new (C) CXXTemporary(Destructor);
}
void CXXTemporary::Destroy(ASTContext &Ctx) {
this->~CXXTemporary();
Ctx.Deallocate(this);
}
CXXBindTemporaryExpr *CXXBindTemporaryExpr::Create(ASTContext &C,
CXXTemporary *Temp,
Expr* SubExpr) {
assert(SubExpr->getType()->isRecordType() &&
"Expression bound to a temporary must have record type!");
return new (C) CXXBindTemporaryExpr(Temp, SubExpr);
}
void CXXBindTemporaryExpr::DoDestroy(ASTContext &C) {
Temp->Destroy(C);
this->~CXXBindTemporaryExpr();
C.Deallocate(this);
}
CXXTemporaryObjectExpr::CXXTemporaryObjectExpr(ASTContext &C,
CXXConstructorDecl *Cons,
QualType writtenTy,
SourceLocation tyBeginLoc,
Expr **Args,
unsigned NumArgs,
SourceLocation rParenLoc)
: CXXConstructExpr(C, CXXTemporaryObjectExprClass, writtenTy, Cons,
false, Args, NumArgs),
TyBeginLoc(tyBeginLoc), RParenLoc(rParenLoc) {
}
CXXConstructExpr *CXXConstructExpr::Create(ASTContext &C, QualType T,
CXXConstructorDecl *D, bool Elidable,
Expr **Args, unsigned NumArgs) {
return new (C) CXXConstructExpr(C, CXXConstructExprClass, T, D, Elidable,
Args, NumArgs);
}
CXXConstructExpr::CXXConstructExpr(ASTContext &C, StmtClass SC, QualType T,
CXXConstructorDecl *D, bool elidable,
Expr **args, unsigned numargs)
: Expr(SC, T,
T->isDependentType(),
(T->isDependentType() ||
CallExpr::hasAnyValueDependentArguments(args, numargs))),
Constructor(D), Elidable(elidable), Args(0), NumArgs(numargs) {
if (NumArgs) {
Args = new (C) Stmt*[NumArgs];
for (unsigned i = 0; i != NumArgs; ++i) {
assert(args[i] && "NULL argument in CXXConstructExpr");
Args[i] = args[i];
}
}
}
CXXConstructExpr::CXXConstructExpr(EmptyShell Empty, ASTContext &C,
unsigned numargs)
: Expr(CXXConstructExprClass, Empty), Args(0), NumArgs(numargs)
{
if (NumArgs)
Args = new (C) Stmt*[NumArgs];
}
void CXXConstructExpr::DoDestroy(ASTContext &C) {
DestroyChildren(C);
if (Args)
C.Deallocate(Args);
this->~CXXConstructExpr();
C.Deallocate(this);
}
CXXExprWithTemporaries::CXXExprWithTemporaries(Expr *subexpr,
CXXTemporary **temps,
unsigned numtemps,
bool shoulddestroytemps)
: Expr(CXXExprWithTemporariesClass, subexpr->getType(),
subexpr->isTypeDependent(), subexpr->isValueDependent()),
SubExpr(subexpr), Temps(0), NumTemps(numtemps),
ShouldDestroyTemps(shoulddestroytemps) {
if (NumTemps > 0) {
Temps = new CXXTemporary*[NumTemps];
for (unsigned i = 0; i < NumTemps; ++i)
Temps[i] = temps[i];
}
}
CXXExprWithTemporaries *CXXExprWithTemporaries::Create(ASTContext &C,
Expr *SubExpr,
CXXTemporary **Temps,
unsigned NumTemps,
bool ShouldDestroyTemps){
return new (C) CXXExprWithTemporaries(SubExpr, Temps, NumTemps,
ShouldDestroyTemps);
}
void CXXExprWithTemporaries::DoDestroy(ASTContext &C) {
DestroyChildren(C);
this->~CXXExprWithTemporaries();
C.Deallocate(this);
}
CXXExprWithTemporaries::~CXXExprWithTemporaries() {
delete[] Temps;
}
// CXXBindTemporaryExpr
Stmt::child_iterator CXXBindTemporaryExpr::child_begin() {
return &SubExpr;
}
Stmt::child_iterator CXXBindTemporaryExpr::child_end() {
return &SubExpr + 1;
}
// CXXConstructExpr
Stmt::child_iterator CXXConstructExpr::child_begin() {
return &Args[0];
}
Stmt::child_iterator CXXConstructExpr::child_end() {
return &Args[0]+NumArgs;
}
// CXXExprWithTemporaries
Stmt::child_iterator CXXExprWithTemporaries::child_begin() {
return &SubExpr;
}
Stmt::child_iterator CXXExprWithTemporaries::child_end() {
return &SubExpr + 1;
}
CXXUnresolvedConstructExpr::CXXUnresolvedConstructExpr(
SourceLocation TyBeginLoc,
QualType T,
SourceLocation LParenLoc,
Expr **Args,
unsigned NumArgs,
SourceLocation RParenLoc)
: Expr(CXXUnresolvedConstructExprClass, T.getNonReferenceType(),
T->isDependentType(), true),
TyBeginLoc(TyBeginLoc),
Type(T),
LParenLoc(LParenLoc),
RParenLoc(RParenLoc),
NumArgs(NumArgs) {
Stmt **StoredArgs = reinterpret_cast<Stmt **>(this + 1);
memcpy(StoredArgs, Args, sizeof(Expr *) * NumArgs);
}
CXXUnresolvedConstructExpr *
CXXUnresolvedConstructExpr::Create(ASTContext &C,
SourceLocation TyBegin,
QualType T,
SourceLocation LParenLoc,
Expr **Args,
unsigned NumArgs,
SourceLocation RParenLoc) {
void *Mem = C.Allocate(sizeof(CXXUnresolvedConstructExpr) +
sizeof(Expr *) * NumArgs);
return new (Mem) CXXUnresolvedConstructExpr(TyBegin, T, LParenLoc,
Args, NumArgs, RParenLoc);
}
Stmt::child_iterator CXXUnresolvedConstructExpr::child_begin() {
return child_iterator(reinterpret_cast<Stmt **>(this + 1));
}
Stmt::child_iterator CXXUnresolvedConstructExpr::child_end() {
return child_iterator(reinterpret_cast<Stmt **>(this + 1) + NumArgs);
}
CXXUnresolvedMemberExpr::CXXUnresolvedMemberExpr(ASTContext &C,
Expr *Base, bool IsArrow,
SourceLocation OperatorLoc,
NestedNameSpecifier *Qualifier,
SourceRange QualifierRange,
NamedDecl *FirstQualifierFoundInScope,
DeclarationName Member,
SourceLocation MemberLoc,
bool HasExplicitTemplateArgs,
SourceLocation LAngleLoc,
const TemplateArgument *TemplateArgs,
unsigned NumTemplateArgs,
SourceLocation RAngleLoc)
: Expr(CXXUnresolvedMemberExprClass, C.DependentTy, true, true),
Base(Base), IsArrow(IsArrow),
HasExplicitTemplateArgumentList(HasExplicitTemplateArgs),
OperatorLoc(OperatorLoc),
Qualifier(Qualifier), QualifierRange(QualifierRange),
FirstQualifierFoundInScope(FirstQualifierFoundInScope),
Member(Member), MemberLoc(MemberLoc) {
if (HasExplicitTemplateArgumentList) {
ExplicitTemplateArgumentList *ETemplateArgs
= getExplicitTemplateArgumentList();
ETemplateArgs->LAngleLoc = LAngleLoc;
ETemplateArgs->RAngleLoc = RAngleLoc;
ETemplateArgs->NumTemplateArgs = NumTemplateArgs;
TemplateArgument *SavedTemplateArgs = ETemplateArgs->getTemplateArgs();
for (unsigned I = 0; I < NumTemplateArgs; ++I)
new (SavedTemplateArgs + I) TemplateArgument(TemplateArgs[I]);
}
}
CXXUnresolvedMemberExpr *
CXXUnresolvedMemberExpr::Create(ASTContext &C,
Expr *Base, bool IsArrow,
SourceLocation OperatorLoc,
NestedNameSpecifier *Qualifier,
SourceRange QualifierRange,
NamedDecl *FirstQualifierFoundInScope,
DeclarationName Member,
SourceLocation MemberLoc,
bool HasExplicitTemplateArgs,
SourceLocation LAngleLoc,
const TemplateArgument *TemplateArgs,
unsigned NumTemplateArgs,
SourceLocation RAngleLoc) {
if (!HasExplicitTemplateArgs)
return new (C) CXXUnresolvedMemberExpr(C, Base, IsArrow, OperatorLoc,
Qualifier, QualifierRange,
FirstQualifierFoundInScope,
Member, MemberLoc);
void *Mem = C.Allocate(sizeof(CXXUnresolvedMemberExpr) +
sizeof(ExplicitTemplateArgumentList) +
sizeof(TemplateArgument) * NumTemplateArgs,
llvm::alignof<CXXUnresolvedMemberExpr>());
return new (Mem) CXXUnresolvedMemberExpr(C, Base, IsArrow, OperatorLoc,
Qualifier, QualifierRange,
FirstQualifierFoundInScope,
Member,
MemberLoc,
HasExplicitTemplateArgs,
LAngleLoc,
TemplateArgs,
NumTemplateArgs,
RAngleLoc);
}
Stmt::child_iterator CXXUnresolvedMemberExpr::child_begin() {
return child_iterator(&Base);
}
Stmt::child_iterator CXXUnresolvedMemberExpr::child_end() {
return child_iterator(&Base + 1);
}