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//===--- SemaTemplateInstantiateDecl.cpp - C++ Template Decl Instantiation ===/
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//===----------------------------------------------------------------------===/
//
// This file implements C++ template instantiation for declarations.
//
//===----------------------------------------------------------------------===/
#include "Sema.h"
#include "clang/AST/ASTConsumer.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/DeclTemplate.h"
#include "clang/AST/DeclVisitor.h"
#include "clang/AST/Expr.h"
#include "llvm/Support/Compiler.h"
using namespace clang;
namespace {
class VISIBILITY_HIDDEN TemplateDeclInstantiator
: public DeclVisitor<TemplateDeclInstantiator, Decl *> {
Sema &SemaRef;
DeclContext *Owner;
const TemplateArgumentList &TemplateArgs;
public:
typedef Sema::OwningExprResult OwningExprResult;
TemplateDeclInstantiator(Sema &SemaRef, DeclContext *Owner,
const TemplateArgumentList &TemplateArgs)
: SemaRef(SemaRef), Owner(Owner), TemplateArgs(TemplateArgs) { }
// FIXME: Once we get closer to completion, replace these manually-written
// declarations with automatically-generated ones from
// clang/AST/DeclNodes.def.
Decl *VisitTranslationUnitDecl(TranslationUnitDecl *D);
Decl *VisitNamespaceDecl(NamespaceDecl *D);
Decl *VisitTypedefDecl(TypedefDecl *D);
Decl *VisitVarDecl(VarDecl *D);
Decl *VisitFieldDecl(FieldDecl *D);
Decl *VisitStaticAssertDecl(StaticAssertDecl *D);
Decl *VisitEnumDecl(EnumDecl *D);
Decl *VisitEnumConstantDecl(EnumConstantDecl *D);
Decl *VisitFunctionDecl(FunctionDecl *D);
Decl *VisitCXXRecordDecl(CXXRecordDecl *D);
Decl *VisitCXXMethodDecl(CXXMethodDecl *D);
Decl *VisitCXXConstructorDecl(CXXConstructorDecl *D);
Decl *VisitCXXDestructorDecl(CXXDestructorDecl *D);
Decl *VisitCXXConversionDecl(CXXConversionDecl *D);
ParmVarDecl *VisitParmVarDecl(ParmVarDecl *D);
Decl *VisitOriginalParmVarDecl(OriginalParmVarDecl *D);
// Base case. FIXME: Remove once we can instantiate everything.
Decl *VisitDecl(Decl *) {
assert(false && "Template instantiation of unknown declaration kind!");
return 0;
}
// Helper functions for instantiating methods.
QualType InstantiateFunctionType(FunctionDecl *D,
llvm::SmallVectorImpl<ParmVarDecl *> &Params);
bool InitFunctionInstantiation(FunctionDecl *New, FunctionDecl *Tmpl);
bool InitMethodInstantiation(CXXMethodDecl *New, CXXMethodDecl *Tmpl);
};
}
Decl *
TemplateDeclInstantiator::VisitTranslationUnitDecl(TranslationUnitDecl *D) {
assert(false && "Translation units cannot be instantiated");
return D;
}
Decl *
TemplateDeclInstantiator::VisitNamespaceDecl(NamespaceDecl *D) {
assert(false && "Namespaces cannot be instantiated");
return D;
}
Decl *TemplateDeclInstantiator::VisitTypedefDecl(TypedefDecl *D) {
bool Invalid = false;
QualType T = D->getUnderlyingType();
if (T->isDependentType()) {
T = SemaRef.InstantiateType(T, TemplateArgs,
D->getLocation(), D->getDeclName());
if (T.isNull()) {
Invalid = true;
T = SemaRef.Context.IntTy;
}
}
// Create the new typedef
TypedefDecl *Typedef
= TypedefDecl::Create(SemaRef.Context, Owner, D->getLocation(),
D->getIdentifier(), T);
if (Invalid)
Typedef->setInvalidDecl();
Owner->addDecl(Typedef);
return Typedef;
}
Decl *TemplateDeclInstantiator::VisitVarDecl(VarDecl *D) {
// Instantiate the type of the declaration
QualType T = SemaRef.InstantiateType(D->getType(), TemplateArgs,
D->getTypeSpecStartLoc(),
D->getDeclName());
if (T.isNull())
return 0;
// Build the instantiated declaration
VarDecl *Var = VarDecl::Create(SemaRef.Context, Owner,
D->getLocation(), D->getIdentifier(),
T, D->getStorageClass(),
D->getTypeSpecStartLoc());
Var->setThreadSpecified(D->isThreadSpecified());
Var->setCXXDirectInitializer(D->hasCXXDirectInitializer());
Var->setDeclaredInCondition(D->isDeclaredInCondition());
// If we are instantiating a static data member defined
// out-of-line, the instantiation will have the same lexical
// context (which will be a namespace scope) as the template.
if (D->isOutOfLine())
Var->setLexicalDeclContext(D->getLexicalDeclContext());
// FIXME: In theory, we could have a previous declaration for variables that
// are not static data members.
bool Redeclaration = false;
SemaRef.CheckVariableDeclaration(Var, 0, Redeclaration);
if (D->isOutOfLine()) {
D->getLexicalDeclContext()->addDecl(Var);
Owner->makeDeclVisibleInContext(Var);
} else {
Owner->addDecl(Var);
}
if (D->getInit()) {
OwningExprResult Init
= SemaRef.InstantiateExpr(D->getInit(), TemplateArgs);
if (Init.isInvalid())
Var->setInvalidDecl();
else
SemaRef.AddInitializerToDecl(Sema::DeclPtrTy::make(Var), move(Init),
D->hasCXXDirectInitializer());
} else if (!Var->isStaticDataMember() || Var->isOutOfLine())
SemaRef.ActOnUninitializedDecl(Sema::DeclPtrTy::make(Var), false);
// Link instantiations of static data members back to the template from
// which they were instantiated.
if (Var->isStaticDataMember())
SemaRef.Context.setInstantiatedFromStaticDataMember(Var, D);
return Var;
}
Decl *TemplateDeclInstantiator::VisitFieldDecl(FieldDecl *D) {
bool Invalid = false;
QualType T = D->getType();
if (T->isDependentType()) {
T = SemaRef.InstantiateType(T, TemplateArgs,
D->getLocation(), D->getDeclName());
if (!T.isNull() && T->isFunctionType()) {
// C++ [temp.arg.type]p3:
// If a declaration acquires a function type through a type
// dependent on a template-parameter and this causes a
// declaration that does not use the syntactic form of a
// function declarator to have function type, the program is
// ill-formed.
SemaRef.Diag(D->getLocation(), diag::err_field_instantiates_to_function)
<< T;
T = QualType();
Invalid = true;
}
}
Expr *BitWidth = D->getBitWidth();
if (Invalid)
BitWidth = 0;
else if (BitWidth) {
// The bit-width expression is not potentially evaluated.
EnterExpressionEvaluationContext Unevaluated(SemaRef, Action::Unevaluated);
OwningExprResult InstantiatedBitWidth
= SemaRef.InstantiateExpr(BitWidth, TemplateArgs);
if (InstantiatedBitWidth.isInvalid()) {
Invalid = true;
BitWidth = 0;
} else
BitWidth = InstantiatedBitWidth.takeAs<Expr>();
}
FieldDecl *Field = SemaRef.CheckFieldDecl(D->getDeclName(), T,
cast<RecordDecl>(Owner),
D->getLocation(),
D->isMutable(),
BitWidth,
D->getTypeSpecStartLoc(),
D->getAccess(),
0);
if (Field) {
if (Invalid)
Field->setInvalidDecl();
Owner->addDecl(Field);
}
return Field;
}
Decl *TemplateDeclInstantiator::VisitStaticAssertDecl(StaticAssertDecl *D) {
Expr *AssertExpr = D->getAssertExpr();
// The expression in a static assertion is not potentially evaluated.
EnterExpressionEvaluationContext Unevaluated(SemaRef, Action::Unevaluated);
OwningExprResult InstantiatedAssertExpr
= SemaRef.InstantiateExpr(AssertExpr, TemplateArgs);
if (InstantiatedAssertExpr.isInvalid())
return 0;
OwningExprResult Message = SemaRef.Clone(D->getMessage());
Decl *StaticAssert
= SemaRef.ActOnStaticAssertDeclaration(D->getLocation(),
move(InstantiatedAssertExpr),
move(Message)).getAs<Decl>();
return StaticAssert;
}
Decl *TemplateDeclInstantiator::VisitEnumDecl(EnumDecl *D) {
EnumDecl *Enum = EnumDecl::Create(SemaRef.Context, Owner,
D->getLocation(), D->getIdentifier(),
D->getTagKeywordLoc(),
/*PrevDecl=*/0);
Enum->setInstantiationOfMemberEnum(D);
Enum->setAccess(D->getAccess());
Owner->addDecl(Enum);
Enum->startDefinition();
llvm::SmallVector<Sema::DeclPtrTy, 4> Enumerators;
EnumConstantDecl *LastEnumConst = 0;
for (EnumDecl::enumerator_iterator EC = D->enumerator_begin(),
ECEnd = D->enumerator_end();
EC != ECEnd; ++EC) {
// The specified value for the enumerator.
OwningExprResult Value = SemaRef.Owned((Expr *)0);
if (Expr *UninstValue = EC->getInitExpr()) {
// The enumerator's value expression is not potentially evaluated.
EnterExpressionEvaluationContext Unevaluated(SemaRef,
Action::Unevaluated);
Value = SemaRef.InstantiateExpr(UninstValue, TemplateArgs);
}
// Drop the initial value and continue.
bool isInvalid = false;
if (Value.isInvalid()) {
Value = SemaRef.Owned((Expr *)0);
isInvalid = true;
}
EnumConstantDecl *EnumConst
= SemaRef.CheckEnumConstant(Enum, LastEnumConst,
EC->getLocation(), EC->getIdentifier(),
move(Value));
if (isInvalid) {
if (EnumConst)
EnumConst->setInvalidDecl();
Enum->setInvalidDecl();
}
if (EnumConst) {
Enum->addDecl(EnumConst);
Enumerators.push_back(Sema::DeclPtrTy::make(EnumConst));
LastEnumConst = EnumConst;
}
}
// FIXME: Fixup LBraceLoc and RBraceLoc
SemaRef.ActOnEnumBody(Enum->getLocation(), SourceLocation(), SourceLocation(),
Sema::DeclPtrTy::make(Enum),
&Enumerators[0], Enumerators.size());
return Enum;
}
Decl *TemplateDeclInstantiator::VisitEnumConstantDecl(EnumConstantDecl *D) {
assert(false && "EnumConstantDecls can only occur within EnumDecls.");
return 0;
}
Decl *TemplateDeclInstantiator::VisitCXXRecordDecl(CXXRecordDecl *D) {
CXXRecordDecl *PrevDecl = 0;
if (D->isInjectedClassName())
PrevDecl = cast<CXXRecordDecl>(Owner);
CXXRecordDecl *Record
= CXXRecordDecl::Create(SemaRef.Context, D->getTagKind(), Owner,
D->getLocation(), D->getIdentifier(),
D->getTagKeywordLoc(), PrevDecl);
Record->setImplicit(D->isImplicit());
Record->setAccess(D->getAccess());
if (!D->isInjectedClassName())
Record->setInstantiationOfMemberClass(D);
Owner->addDecl(Record);
return Record;
}
Decl *TemplateDeclInstantiator::VisitFunctionDecl(FunctionDecl *D) {
// Check whether there is already a function template specialization for
// this declaration.
FunctionTemplateDecl *FunctionTemplate = D->getDescribedFunctionTemplate();
void *InsertPos = 0;
if (FunctionTemplate) {
llvm::FoldingSetNodeID ID;
FunctionTemplateSpecializationInfo::Profile(ID,
TemplateArgs.getFlatArgumentList(),
TemplateArgs.flat_size(),
SemaRef.Context);
FunctionTemplateSpecializationInfo *Info
= FunctionTemplate->getSpecializations().FindNodeOrInsertPos(ID,
InsertPos);
// If we already have a function template specialization, return it.
if (Info)
return Info->Function;
}
Sema::LocalInstantiationScope Scope(SemaRef);
llvm::SmallVector<ParmVarDecl *, 4> Params;
QualType T = InstantiateFunctionType(D, Params);
if (T.isNull())
return 0;
// Build the instantiated method declaration.
FunctionDecl *Function
= FunctionDecl::Create(SemaRef.Context, Owner, D->getLocation(),
D->getDeclName(), T, D->getStorageClass(),
D->isInline(), D->hasWrittenPrototype(),
D->getTypeSpecStartLoc());
// FIXME: friend functions
// Attach the parameters
for (unsigned P = 0; P < Params.size(); ++P)
Params[P]->setOwningFunction(Function);
Function->setParams(SemaRef.Context, Params.data(), Params.size());
if (InitFunctionInstantiation(Function, D))
Function->setInvalidDecl();
bool Redeclaration = false;
bool OverloadableAttrRequired = false;
NamedDecl *PrevDecl = 0;
SemaRef.CheckFunctionDeclaration(Function, PrevDecl, Redeclaration,
/*FIXME:*/OverloadableAttrRequired);
if (FunctionTemplate) {
// Record this function template specialization.
Function->setFunctionTemplateSpecialization(SemaRef.Context,
FunctionTemplate,
&TemplateArgs,
InsertPos);
}
return Function;
}
Decl *TemplateDeclInstantiator::VisitCXXMethodDecl(CXXMethodDecl *D) {
// FIXME: Look for existing, explicit specializations.
Sema::LocalInstantiationScope Scope(SemaRef);
llvm::SmallVector<ParmVarDecl *, 4> Params;
QualType T = InstantiateFunctionType(D, Params);
if (T.isNull())
return 0;
// Build the instantiated method declaration.
CXXRecordDecl *Record = cast<CXXRecordDecl>(Owner);
CXXMethodDecl *Method
= CXXMethodDecl::Create(SemaRef.Context, Record, D->getLocation(),
D->getDeclName(), T, D->isStatic(),
D->isInline());
Method->setInstantiationOfMemberFunction(D);
// If we are instantiating a member function defined
// out-of-line, the instantiation will have the same lexical
// context (which will be a namespace scope) as the template.
if (D->isOutOfLine())
Method->setLexicalDeclContext(D->getLexicalDeclContext());
// Attach the parameters
for (unsigned P = 0; P < Params.size(); ++P)
Params[P]->setOwningFunction(Method);
Method->setParams(SemaRef.Context, Params.data(), Params.size());
if (InitMethodInstantiation(Method, D))
Method->setInvalidDecl();
NamedDecl *PrevDecl
= SemaRef.LookupQualifiedName(Owner, Method->getDeclName(),
Sema::LookupOrdinaryName, true);
// In C++, the previous declaration we find might be a tag type
// (class or enum). In this case, the new declaration will hide the
// tag type. Note that this does does not apply if we're declaring a
// typedef (C++ [dcl.typedef]p4).
if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag)
PrevDecl = 0;
bool Redeclaration = false;
bool OverloadableAttrRequired = false;
SemaRef.CheckFunctionDeclaration(Method, PrevDecl, Redeclaration,
/*FIXME:*/OverloadableAttrRequired);
if (!Method->isInvalidDecl() || !PrevDecl)
Owner->addDecl(Method);
return Method;
}
Decl *TemplateDeclInstantiator::VisitCXXConstructorDecl(CXXConstructorDecl *D) {
// FIXME: Look for existing, explicit specializations.
Sema::LocalInstantiationScope Scope(SemaRef);
llvm::SmallVector<ParmVarDecl *, 4> Params;
QualType T = InstantiateFunctionType(D, Params);
if (T.isNull())
return 0;
// Build the instantiated method declaration.
CXXRecordDecl *Record = cast<CXXRecordDecl>(Owner);
QualType ClassTy = SemaRef.Context.getTypeDeclType(Record);
DeclarationName Name
= SemaRef.Context.DeclarationNames.getCXXConstructorName(
SemaRef.Context.getCanonicalType(ClassTy));
CXXConstructorDecl *Constructor
= CXXConstructorDecl::Create(SemaRef.Context, Record, D->getLocation(),
Name, T, D->isExplicit(), D->isInline(),
false);
Constructor->setInstantiationOfMemberFunction(D);
// Attach the parameters
for (unsigned P = 0; P < Params.size(); ++P)
Params[P]->setOwningFunction(Constructor);
Constructor->setParams(SemaRef.Context, Params.data(), Params.size());
if (InitMethodInstantiation(Constructor, D))
Constructor->setInvalidDecl();
NamedDecl *PrevDecl
= SemaRef.LookupQualifiedName(Owner, Name, Sema::LookupOrdinaryName, true);
// In C++, the previous declaration we find might be a tag type
// (class or enum). In this case, the new declaration will hide the
// tag type. Note that this does does not apply if we're declaring a
// typedef (C++ [dcl.typedef]p4).
if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag)
PrevDecl = 0;
bool Redeclaration = false;
bool OverloadableAttrRequired = false;
SemaRef.CheckFunctionDeclaration(Constructor, PrevDecl, Redeclaration,
/*FIXME:*/OverloadableAttrRequired);
Record->addedConstructor(SemaRef.Context, Constructor);
Owner->addDecl(Constructor);
return Constructor;
}
Decl *TemplateDeclInstantiator::VisitCXXDestructorDecl(CXXDestructorDecl *D) {
// FIXME: Look for existing, explicit specializations.
Sema::LocalInstantiationScope Scope(SemaRef);
llvm::SmallVector<ParmVarDecl *, 4> Params;
QualType T = InstantiateFunctionType(D, Params);
if (T.isNull())
return 0;
assert(Params.size() == 0 && "Destructor with parameters?");
// Build the instantiated destructor declaration.
CXXRecordDecl *Record = cast<CXXRecordDecl>(Owner);
QualType ClassTy =
SemaRef.Context.getCanonicalType(SemaRef.Context.getTypeDeclType(Record));
CXXDestructorDecl *Destructor
= CXXDestructorDecl::Create(SemaRef.Context, Record,
D->getLocation(),
SemaRef.Context.DeclarationNames.getCXXDestructorName(ClassTy),
T, D->isInline(), false);
Destructor->setInstantiationOfMemberFunction(D);
if (InitMethodInstantiation(Destructor, D))
Destructor->setInvalidDecl();
bool Redeclaration = false;
bool OverloadableAttrRequired = false;
NamedDecl *PrevDecl = 0;
SemaRef.CheckFunctionDeclaration(Destructor, PrevDecl, Redeclaration,
/*FIXME:*/OverloadableAttrRequired);
Owner->addDecl(Destructor);
return Destructor;
}
Decl *TemplateDeclInstantiator::VisitCXXConversionDecl(CXXConversionDecl *D) {
// FIXME: Look for existing, explicit specializations.
Sema::LocalInstantiationScope Scope(SemaRef);
llvm::SmallVector<ParmVarDecl *, 4> Params;
QualType T = InstantiateFunctionType(D, Params);
if (T.isNull())
return 0;
assert(Params.size() == 0 && "Destructor with parameters?");
// Build the instantiated conversion declaration.
CXXRecordDecl *Record = cast<CXXRecordDecl>(Owner);
QualType ClassTy = SemaRef.Context.getTypeDeclType(Record);
QualType ConvTy
= SemaRef.Context.getCanonicalType(T->getAsFunctionType()->getResultType());
CXXConversionDecl *Conversion
= CXXConversionDecl::Create(SemaRef.Context, Record,
D->getLocation(),
SemaRef.Context.DeclarationNames.getCXXConversionFunctionName(ConvTy),
T, D->isInline(), D->isExplicit());
Conversion->setInstantiationOfMemberFunction(D);
if (InitMethodInstantiation(Conversion, D))
Conversion->setInvalidDecl();
bool Redeclaration = false;
bool OverloadableAttrRequired = false;
NamedDecl *PrevDecl = 0;
SemaRef.CheckFunctionDeclaration(Conversion, PrevDecl, Redeclaration,
/*FIXME:*/OverloadableAttrRequired);
Owner->addDecl(Conversion);
return Conversion;
}
ParmVarDecl *TemplateDeclInstantiator::VisitParmVarDecl(ParmVarDecl *D) {
QualType OrigT = SemaRef.InstantiateType(D->getOriginalType(), TemplateArgs,
D->getLocation(), D->getDeclName());
if (OrigT.isNull())
return 0;
QualType T = SemaRef.adjustParameterType(OrigT);
if (D->getDefaultArg()) {
// FIXME: Leave a marker for "uninstantiated" default
// arguments. They only get instantiated on demand at the call
// site.
unsigned DiagID = SemaRef.Diags.getCustomDiagID(Diagnostic::Warning,
"sorry, dropping default argument during template instantiation");
SemaRef.Diag(D->getDefaultArg()->getSourceRange().getBegin(), DiagID)
<< D->getDefaultArg()->getSourceRange();
}
// Allocate the parameter
ParmVarDecl *Param = 0;
if (T == OrigT)
Param = ParmVarDecl::Create(SemaRef.Context, Owner, D->getLocation(),
D->getIdentifier(), T, D->getStorageClass(),
0);
else
Param = OriginalParmVarDecl::Create(SemaRef.Context, Owner,
D->getLocation(), D->getIdentifier(),
T, OrigT, D->getStorageClass(), 0);
// Note: we don't try to instantiate function parameters until after
// we've instantiated the function's type. Therefore, we don't have
// to check for 'void' parameter types here.
SemaRef.CurrentInstantiationScope->InstantiatedLocal(D, Param);
return Param;
}
Decl *
TemplateDeclInstantiator::VisitOriginalParmVarDecl(OriginalParmVarDecl *D) {
// Since parameter types can decay either before or after
// instantiation, we simply treat OriginalParmVarDecls as
// ParmVarDecls the same way, and create one or the other depending
// on what happens after template instantiation.
return VisitParmVarDecl(D);
}
Decl *Sema::InstantiateDecl(Decl *D, DeclContext *Owner,
const TemplateArgumentList &TemplateArgs) {
TemplateDeclInstantiator Instantiator(*this, Owner, TemplateArgs);
return Instantiator.Visit(D);
}
/// \brief Instantiates the type of the given function, including
/// instantiating all of the function parameters.
///
/// \param D The function that we will be instantiated
///
/// \param Params the instantiated parameter declarations
/// \returns the instantiated function's type if successfull, a NULL
/// type if there was an error.
QualType
TemplateDeclInstantiator::InstantiateFunctionType(FunctionDecl *D,
llvm::SmallVectorImpl<ParmVarDecl *> &Params) {
bool InvalidDecl = false;
// Instantiate the function parameters
TemplateDeclInstantiator ParamInstantiator(SemaRef, 0, TemplateArgs);
llvm::SmallVector<QualType, 4> ParamTys;
for (FunctionDecl::param_iterator P = D->param_begin(),
PEnd = D->param_end();
P != PEnd; ++P) {
if (ParmVarDecl *PInst = ParamInstantiator.VisitParmVarDecl(*P)) {
if (PInst->getType()->isVoidType()) {
SemaRef.Diag(PInst->getLocation(), diag::err_param_with_void_type);
PInst->setInvalidDecl();
}
else if (SemaRef.RequireNonAbstractType(PInst->getLocation(),
PInst->getType(),
diag::err_abstract_type_in_decl,
Sema::AbstractParamType))
PInst->setInvalidDecl();
Params.push_back(PInst);
ParamTys.push_back(PInst->getType());
if (PInst->isInvalidDecl())
InvalidDecl = true;
} else
InvalidDecl = true;
}
// FIXME: Deallocate dead declarations.
if (InvalidDecl)
return QualType();
const FunctionProtoType *Proto = D->getType()->getAsFunctionProtoType();
assert(Proto && "Missing prototype?");
QualType ResultType
= SemaRef.InstantiateType(Proto->getResultType(), TemplateArgs,
D->getLocation(), D->getDeclName());
if (ResultType.isNull())
return QualType();
return SemaRef.BuildFunctionType(ResultType, ParamTys.data(), ParamTys.size(),
Proto->isVariadic(), Proto->getTypeQuals(),
D->getLocation(), D->getDeclName());
}
/// \brief Initializes the common fields of an instantiation function
/// declaration (New) from the corresponding fields of its template (Tmpl).
///
/// \returns true if there was an error
bool
TemplateDeclInstantiator::InitFunctionInstantiation(FunctionDecl *New,
FunctionDecl *Tmpl) {
if (Tmpl->isDeleted())
New->setDeleted();
// If we are performing substituting explicitly-specified template arguments
// or deduced template arguments into a function template and we reach this
// point, we are now past the point where SFINAE applies and have committed
// to keeping the new function template specialization. We therefore
// convert the active template instantiation for the function template
// into a template instantiation for this specific function template
// specialization, which is not a SFINAE context, so that we diagnose any
// further errors in the declaration itself.
typedef Sema::ActiveTemplateInstantiation ActiveInstType;
ActiveInstType &ActiveInst = SemaRef.ActiveTemplateInstantiations.back();
if (ActiveInst.Kind == ActiveInstType::ExplicitTemplateArgumentSubstitution ||
ActiveInst.Kind == ActiveInstType::DeducedTemplateArgumentSubstitution) {
if (FunctionTemplateDecl *FunTmpl
= dyn_cast<FunctionTemplateDecl>((Decl *)ActiveInst.Entity)) {
assert(FunTmpl->getTemplatedDecl() == Tmpl &&
"Deduction from the wrong function template?");
(void) FunTmpl;
ActiveInst.Kind = ActiveInstType::TemplateInstantiation;
ActiveInst.Entity = reinterpret_cast<uintptr_t>(New);
}
}
return false;
}
/// \brief Initializes common fields of an instantiated method
/// declaration (New) from the corresponding fields of its template
/// (Tmpl).
///
/// \returns true if there was an error
bool
TemplateDeclInstantiator::InitMethodInstantiation(CXXMethodDecl *New,
CXXMethodDecl *Tmpl) {
if (InitFunctionInstantiation(New, Tmpl))
return true;
CXXRecordDecl *Record = cast<CXXRecordDecl>(Owner);
New->setAccess(Tmpl->getAccess());
if (Tmpl->isVirtualAsWritten()) {
New->setVirtualAsWritten(true);
Record->setAggregate(false);
Record->setPOD(false);
Record->setPolymorphic(true);
}
if (Tmpl->isPure()) {
New->setPure();
Record->setAbstract(true);
}
// FIXME: attributes
// FIXME: New needs a pointer to Tmpl
return false;
}
/// \brief Instantiate the definition of the given function from its
/// template.
///
/// \param PointOfInstantiation the point at which the instantiation was
/// required. Note that this is not precisely a "point of instantiation"
/// for the function, but it's close.
///
/// \param Function the already-instantiated declaration of a
/// function template specialization or member function of a class template
/// specialization.
///
/// \param Recursive if true, recursively instantiates any functions that
/// are required by this instantiation.
void Sema::InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
FunctionDecl *Function,
bool Recursive) {
if (Function->isInvalidDecl())
return;
assert(!Function->getBody() && "Already instantiated!");
// Find the function body that we'll be substituting.
const FunctionDecl *PatternDecl = 0;
if (FunctionTemplateDecl *Primary = Function->getPrimaryTemplate())
PatternDecl = Primary->getTemplatedDecl();
else
PatternDecl = Function->getInstantiatedFromMemberFunction();
Stmt *Pattern = 0;
if (PatternDecl)
Pattern = PatternDecl->getBody(PatternDecl);
if (!Pattern)
return;
InstantiatingTemplate Inst(*this, PointOfInstantiation, Function);
if (Inst)
return;
// If we're performing recursive template instantiation, create our own
// queue of pending implicit instantiations that we will instantiate later,
// while we're still within our own instantiation context.
std::deque<PendingImplicitInstantiation> SavedPendingImplicitInstantiations;
if (Recursive)
PendingImplicitInstantiations.swap(SavedPendingImplicitInstantiations);
ActOnStartOfFunctionDef(0, DeclPtrTy::make(Function));
// Introduce a new scope where local variable instantiations will be
// recorded.
LocalInstantiationScope Scope(*this);
// Introduce the instantiated function parameters into the local
// instantiation scope.
for (unsigned I = 0, N = PatternDecl->getNumParams(); I != N; ++I)
Scope.InstantiatedLocal(PatternDecl->getParamDecl(I),
Function->getParamDecl(I));
// Enter the scope of this instantiation. We don't use
// PushDeclContext because we don't have a scope.
DeclContext *PreviousContext = CurContext;
CurContext = Function;
// Instantiate the function body.
OwningStmtResult Body
= InstantiateStmt(Pattern, getTemplateInstantiationArgs(Function));
ActOnFinishFunctionBody(DeclPtrTy::make(Function), move(Body),
/*IsInstantiation=*/true);
CurContext = PreviousContext;
DeclGroupRef DG(Function);
Consumer.HandleTopLevelDecl(DG);
if (Recursive) {
// Instantiate any pending implicit instantiations found during the
// instantiation of this template.
PerformPendingImplicitInstantiations();
// Restore the set of pending implicit instantiations.
PendingImplicitInstantiations.swap(SavedPendingImplicitInstantiations);
}
}
/// \brief Instantiate the definition of the given variable from its
/// template.
///
/// \param PointOfInstantiation the point at which the instantiation was
/// required. Note that this is not precisely a "point of instantiation"
/// for the function, but it's close.
///
/// \param Var the already-instantiated declaration of a static member
/// variable of a class template specialization.
///
/// \param Recursive if true, recursively instantiates any functions that
/// are required by this instantiation.
void Sema::InstantiateStaticDataMemberDefinition(
SourceLocation PointOfInstantiation,
VarDecl *Var,
bool Recursive) {
if (Var->isInvalidDecl())
return;
// Find the out-of-line definition of this static data member.
// FIXME: Do we have to look for specializations separately?
VarDecl *Def = Var->getInstantiatedFromStaticDataMember();
bool FoundOutOfLineDef = false;
assert(Def && "This data member was not instantiated from a template?");
assert(Def->isStaticDataMember() && "Not a static data member?");
for (VarDecl::redecl_iterator RD = Def->redecls_begin(),
RDEnd = Def->redecls_end();
RD != RDEnd; ++RD) {
if (RD->getLexicalDeclContext()->isFileContext()) {
Def = *RD;
FoundOutOfLineDef = true;
}
}
if (!FoundOutOfLineDef) {
// We did not find an out-of-line definition of this static data member,
// so we won't perform any instantiation. Rather, we rely on the user to
// instantiate this definition (or provide a specialization for it) in
// another translation unit.
return;
}
InstantiatingTemplate Inst(*this, PointOfInstantiation, Var);
if (Inst)
return;
// If we're performing recursive template instantiation, create our own
// queue of pending implicit instantiations that we will instantiate later,
// while we're still within our own instantiation context.
std::deque<PendingImplicitInstantiation> SavedPendingImplicitInstantiations;
if (Recursive)
PendingImplicitInstantiations.swap(SavedPendingImplicitInstantiations);
// Enter the scope of this instantiation. We don't use
// PushDeclContext because we don't have a scope.
DeclContext *PreviousContext = CurContext;
CurContext = Var->getDeclContext();
#if 0
// Instantiate the initializer of this static data member.
OwningExprResult Init
= InstantiateExpr(Def->getInit(), getTemplateInstantiationArgs(Var));
if (Init.isInvalid()) {
// If instantiation of the initializer failed, mark the declaration invalid
// and don't instantiate anything else that was triggered by this
// instantiation.
Var->setInvalidDecl();
// Restore the set of pending implicit instantiations.
PendingImplicitInstantiations.swap(SavedPendingImplicitInstantiations);
return;
}
// Type-check the initializer.
if (Init.get())
AddInitializerToDecl(DeclPtrTy::make(Var), move(Init),
Def->hasCXXDirectInitializer());
else
ActOnUninitializedDecl(DeclPtrTy::make(Var), false);
#else
Var = cast_or_null<VarDecl>(InstantiateDecl(Def, Var->getDeclContext(),
getTemplateInstantiationArgs(Var)));
#endif
CurContext = PreviousContext;
if (Var) {
DeclGroupRef DG(Var);
Consumer.HandleTopLevelDecl(DG);
}
if (Recursive) {
// Instantiate any pending implicit instantiations found during the
// instantiation of this template.
PerformPendingImplicitInstantiations();
// Restore the set of pending implicit instantiations.
PendingImplicitInstantiations.swap(SavedPendingImplicitInstantiations);
}
}
static bool isInstantiationOf(ASTContext &Ctx, NamedDecl *D, Decl *Other) {
if (D->getKind() != Other->getKind())
return false;
if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Other))
return Record->getInstantiatedFromMemberClass()->getCanonicalDecl()
== D->getCanonicalDecl();
if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Other))
return Function->getInstantiatedFromMemberFunction()->getCanonicalDecl()
== D->getCanonicalDecl();
if (EnumDecl *Enum = dyn_cast<EnumDecl>(Other))
return Enum->getInstantiatedFromMemberEnum()->getCanonicalDecl()
== D->getCanonicalDecl();
if (VarDecl *Var = dyn_cast<VarDecl>(Other))
if (Var->isStaticDataMember())
return Var->getInstantiatedFromStaticDataMember()->getCanonicalDecl()
== D->getCanonicalDecl();
// FIXME: How can we find instantiations of anonymous unions?
return D->getDeclName() && isa<NamedDecl>(Other) &&
D->getDeclName() == cast<NamedDecl>(Other)->getDeclName();
}
template<typename ForwardIterator>
static NamedDecl *findInstantiationOf(ASTContext &Ctx,
NamedDecl *D,
ForwardIterator first,
ForwardIterator last) {
for (; first != last; ++first)
if (isInstantiationOf(Ctx, D, *first))
return cast<NamedDecl>(*first);
return 0;
}
/// \brief Find the instantiation of the given declaration within the
/// current instantiation.
///
/// This routine is intended to be used when \p D is a declaration
/// referenced from within a template, that needs to mapped into the
/// corresponding declaration within an instantiation. For example,
/// given:
///
/// \code
/// template<typename T>
/// struct X {
/// enum Kind {
/// KnownValue = sizeof(T)
/// };
///
/// bool getKind() const { return KnownValue; }
/// };
///
/// template struct X<int>;
/// \endcode
///
/// In the instantiation of X<int>::getKind(), we need to map the
/// EnumConstantDecl for KnownValue (which refers to
/// X<T>::<Kind>::KnownValue) to its instantiation
/// (X<int>::<Kind>::KnownValue). InstantiateCurrentDeclRef() performs
/// this mapping from within the instantiation of X<int>.
NamedDecl * Sema::InstantiateCurrentDeclRef(NamedDecl *D) {
DeclContext *ParentDC = D->getDeclContext();
if (isa<ParmVarDecl>(D) || ParentDC->isFunctionOrMethod()) {
// D is a local of some kind. Look into the map of local
// declarations to their instantiations.
return cast<NamedDecl>(CurrentInstantiationScope->getInstantiationOf(D));
}
if (NamedDecl *ParentDecl = dyn_cast<NamedDecl>(ParentDC)) {
ParentDecl = InstantiateCurrentDeclRef(ParentDecl);
if (!ParentDecl)
return 0;
ParentDC = cast<DeclContext>(ParentDecl);
}
if (ParentDC != D->getDeclContext()) {
// We performed some kind of instantiation in the parent context,
// so now we need to look into the instantiated parent context to
// find the instantiation of the declaration D.
NamedDecl *Result = 0;
if (D->getDeclName()) {
DeclContext::lookup_result Found = ParentDC->lookup(D->getDeclName());
Result = findInstantiationOf(Context, D, Found.first, Found.second);
} else {
// Since we don't have a name for the entity we're looking for,
// our only option is to walk through all of the declarations to
// find that name. This will occur in a few cases:
//
// - anonymous struct/union within a template
// - unnamed class/struct/union/enum within a template
//
// FIXME: Find a better way to find these instantiations!
Result = findInstantiationOf(Context, D,
ParentDC->decls_begin(),
ParentDC->decls_end());
}
assert(Result && "Unable to find instantiation of declaration!");
D = Result;
}
if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(D))
if (ClassTemplateDecl *ClassTemplate
= Record->getDescribedClassTemplate()) {
// When the declaration D was parsed, it referred to the current
// instantiation. Therefore, look through the current context,
// which contains actual instantiations, to find the
// instantiation of the "current instantiation" that D refers
// to. Alternatively, we could just instantiate the
// injected-class-name with the current template arguments, but
// such an instantiation is far more expensive.
for (DeclContext *DC = CurContext; !DC->isFileContext();
DC = DC->getParent()) {
if (ClassTemplateSpecializationDecl *Spec
= dyn_cast<ClassTemplateSpecializationDecl>(DC))
if (Spec->getSpecializedTemplate()->getCanonicalDecl()
== ClassTemplate->getCanonicalDecl())
return Spec;
}
assert(false &&
"Unable to find declaration for the current instantiation");
}
return D;
}
/// \brief Performs template instantiation for all implicit template
/// instantiations we have seen until this point.
void Sema::PerformPendingImplicitInstantiations() {
while (!PendingImplicitInstantiations.empty()) {
PendingImplicitInstantiation Inst = PendingImplicitInstantiations.front();
PendingImplicitInstantiations.pop_front();
// Instantiate function definitions
if (FunctionDecl *Function = dyn_cast<FunctionDecl>(Inst.first)) {
if (!Function->getBody())
InstantiateFunctionDefinition(/*FIXME:*/Inst.second, Function, true);
continue;
}
// Instantiate static data member definitions.
VarDecl *Var = cast<VarDecl>(Inst.first);
assert(Var->isStaticDataMember() && "Not a static data member?");
InstantiateStaticDataMemberDefinition(/*FIXME:*/Inst.second, Var, true);
}
}