[Concept] Associated Constraints Infrastructure
Add code to correctly calculate the associated constraints of a template (no enforcement yet).
D41284 on Phabricator.
llvm-svn: 374938
diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index cd6ea7f..1a3bde0 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -738,7 +738,7 @@
cast<TemplateTemplateParmDecl>(*P)));
}
- assert(!TTP->getRequiresClause() &&
+ assert(!TTP->getTemplateParameters()->getRequiresClause() &&
"Unexpected requires-clause on template template-parameter");
Expr *const CanonRequiresClause = nullptr;
diff --git a/clang/lib/AST/DeclTemplate.cpp b/clang/lib/AST/DeclTemplate.cpp
index ccfc292..7e013c6 100644
--- a/clang/lib/AST/DeclTemplate.cpp
+++ b/clang/lib/AST/DeclTemplate.cpp
@@ -70,6 +70,8 @@
}
if (RequiresClause) {
*getTrailingObjects<Expr *>() = RequiresClause;
+ if (RequiresClause->containsUnexpandedParameterPack())
+ ContainsUnexpandedParameterPack = true;
}
}
@@ -136,6 +138,18 @@
}
}
+void TemplateParameterList::
+getAssociatedConstraints(llvm::SmallVectorImpl<const Expr *> &AC) const {
+ // TODO: Concepts: Collect immediately-introduced constraints.
+ if (HasRequiresClause)
+ AC.push_back(getRequiresClause());
+}
+
+bool TemplateParameterList::hasAssociatedConstraints() const {
+ // TODO: Concepts: Regard immediately-introduced constraints.
+ return HasRequiresClause;
+}
+
namespace clang {
void *allocateDefaultArgStorageChain(const ASTContext &C) {
@@ -145,6 +159,28 @@
} // namespace clang
//===----------------------------------------------------------------------===//
+// TemplateDecl Implementation
+//===----------------------------------------------------------------------===//
+
+TemplateDecl::TemplateDecl(Kind DK, DeclContext *DC, SourceLocation L,
+ DeclarationName Name, TemplateParameterList *Params,
+ NamedDecl *Decl)
+ : NamedDecl(DK, DC, L, Name), TemplatedDecl(Decl), TemplateParams(Params) {}
+
+void TemplateDecl::anchor() {}
+
+void TemplateDecl::
+getAssociatedConstraints(llvm::SmallVectorImpl<const Expr *> &AC) const {
+ // TODO: Concepts: Append function trailing requires clause.
+ TemplateParams->getAssociatedConstraints(AC);
+}
+
+bool TemplateDecl::hasAssociatedConstraints() const {
+ // TODO: Concepts: Regard function trailing requires clause.
+ return TemplateParams->hasAssociatedConstraints();
+}
+
+//===----------------------------------------------------------------------===//
// RedeclarableTemplateDecl Implementation
//===----------------------------------------------------------------------===//
@@ -344,19 +380,10 @@
SourceLocation L,
DeclarationName Name,
TemplateParameterList *Params,
- NamedDecl *Decl,
- Expr *AssociatedConstraints) {
+ NamedDecl *Decl) {
AdoptTemplateParameterList(Params, cast<DeclContext>(Decl));
- if (!AssociatedConstraints) {
- return new (C, DC) ClassTemplateDecl(C, DC, L, Name, Params, Decl);
- }
-
- auto *const CTDI = new (C) ConstrainedTemplateDeclInfo;
- auto *const New =
- new (C, DC) ClassTemplateDecl(CTDI, C, DC, L, Name, Params, Decl);
- New->setAssociatedConstraints(AssociatedConstraints);
- return New;
+ return new (C, DC) ClassTemplateDecl(C, DC, L, Name, Params, Decl);
}
ClassTemplateDecl *ClassTemplateDecl::CreateDeserialized(ASTContext &C,
@@ -708,12 +735,6 @@
}
//===----------------------------------------------------------------------===//
-// TemplateDecl Implementation
-//===----------------------------------------------------------------------===//
-
-void TemplateDecl::anchor() {}
-
-//===----------------------------------------------------------------------===//
// ClassTemplateSpecializationDecl Implementation
//===----------------------------------------------------------------------===//
diff --git a/clang/lib/Sema/SemaConcept.cpp b/clang/lib/Sema/SemaConcept.cpp
index 3131609..848ccf5 100644
--- a/clang/lib/Sema/SemaConcept.cpp
+++ b/clang/lib/Sema/SemaConcept.cpp
@@ -122,4 +122,4 @@
IsSatisfied = EvalResult.Val.getInt().getBoolValue();
return false;
-}
+}
\ No newline at end of file
diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index cb756eb..2871511 100644
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -45,27 +45,7 @@
return SourceRange(Ps[0]->getTemplateLoc(), Ps[N-1]->getRAngleLoc());
}
-namespace clang {
-/// [temp.constr.decl]p2: A template's associated constraints are
-/// defined as a single constraint-expression derived from the introduced
-/// constraint-expressions [ ... ].
-///
-/// \param Params The template parameter list and optional requires-clause.
-///
-/// \param FD The underlying templated function declaration for a function
-/// template.
-static Expr *formAssociatedConstraints(TemplateParameterList *Params,
- FunctionDecl *FD);
-}
-
-static Expr *clang::formAssociatedConstraints(TemplateParameterList *Params,
- FunctionDecl *FD) {
- // FIXME: Concepts: collect additional introduced constraint-expressions
- assert(!FD && "Cannot collect constraints from function declaration yet.");
- return Params->getRequiresClause();
-}
-
-/// Determine whether the declaration found is acceptable as the name
+/// \brief Determine whether the declaration found is acceptable as the name
/// of a template and, if so, return that template declaration. Otherwise,
/// returns null.
///
@@ -1533,9 +1513,6 @@
}
}
- // TODO Memory management; associated constraints are not always stored.
- Expr *const CurAC = formAssociatedConstraints(TemplateParams, nullptr);
-
if (PrevClassTemplate) {
// Ensure that the template parameter lists are compatible. Skip this check
// for a friend in a dependent context: the template parameter list itself
@@ -1547,30 +1524,6 @@
TPL_TemplateMatch))
return true;
- // Check for matching associated constraints on redeclarations.
- const Expr *const PrevAC = PrevClassTemplate->getAssociatedConstraints();
- const bool RedeclACMismatch = [&] {
- if (!(CurAC || PrevAC))
- return false; // Nothing to check; no mismatch.
- if (CurAC && PrevAC) {
- llvm::FoldingSetNodeID CurACInfo, PrevACInfo;
- CurAC->Profile(CurACInfo, Context, /*Canonical=*/true);
- PrevAC->Profile(PrevACInfo, Context, /*Canonical=*/true);
- if (CurACInfo == PrevACInfo)
- return false; // All good; no mismatch.
- }
- return true;
- }();
-
- if (RedeclACMismatch) {
- Diag(CurAC ? CurAC->getBeginLoc() : NameLoc,
- diag::err_template_different_associated_constraints);
- Diag(PrevAC ? PrevAC->getBeginLoc() : PrevClassTemplate->getLocation(),
- diag::note_template_prev_declaration)
- << /*declaration*/ 0;
- return true;
- }
-
// C++ [temp.class]p4:
// In a redeclaration, partial specialization, explicit
// specialization or explicit instantiation of a class template,
@@ -1674,15 +1627,10 @@
AddMsStructLayoutForRecord(NewClass);
}
- // Attach the associated constraints when the declaration will not be part of
- // a decl chain.
- Expr *const ACtoAttach =
- PrevClassTemplate && ShouldAddRedecl ? nullptr : CurAC;
-
ClassTemplateDecl *NewTemplate
= ClassTemplateDecl::Create(Context, SemanticContext, NameLoc,
DeclarationName(Name), TemplateParams,
- NewClass, ACtoAttach);
+ NewClass);
if (ShouldAddRedecl)
NewTemplate->setPreviousDecl(PrevClassTemplate);
@@ -7266,6 +7214,9 @@
TemplateArgLoc);
}
+ // TODO: Concepts: Match immediately-introduced-constraint for type
+ // constraints
+
return true;
}
@@ -7291,6 +7242,15 @@
<< SourceRange(Old->getTemplateLoc(), Old->getRAngleLoc());
}
+static void
+DiagnoseTemplateParameterListRequiresClauseMismatch(Sema &S,
+ TemplateParameterList *New,
+ TemplateParameterList *Old){
+ S.Diag(New->getTemplateLoc(), diag::err_template_different_requires_clause);
+ S.Diag(Old->getTemplateLoc(), diag::note_template_prev_declaration)
+ << /*declaration*/0;
+}
+
/// Determine whether the given template parameter lists are
/// equivalent.
///
@@ -7380,6 +7340,27 @@
return false;
}
+ if (Kind != TPL_TemplateTemplateArgumentMatch) {
+ const Expr *NewRC = New->getRequiresClause();
+ const Expr *OldRC = Old->getRequiresClause();
+ if (!NewRC != !OldRC) {
+ if (Complain)
+ DiagnoseTemplateParameterListRequiresClauseMismatch(*this, New, Old);
+ return false;
+ }
+
+ if (NewRC) {
+ llvm::FoldingSetNodeID OldRCID, NewRCID;
+ OldRC->Profile(OldRCID, Context, /*Canonical=*/true);
+ NewRC->Profile(NewRCID, Context, /*Canonical=*/true);
+ if (OldRCID != NewRCID) {
+ if (Complain)
+ DiagnoseTemplateParameterListRequiresClauseMismatch(*this, New, Old);
+ return false;
+ }
+ }
+ }
+
return true;
}
@@ -8089,10 +8070,9 @@
TemplateParameterLists.front(),
ConstraintExpr);
- if (NewDecl->getAssociatedConstraints()) {
+ if (NewDecl->hasAssociatedConstraints()) {
// C++2a [temp.concept]p4:
// A concept shall not have associated constraints.
- // TODO: Make a test once we have actual associated constraints.
Diag(NameLoc, diag::err_concept_no_associated_constraints);
NewDecl->setInvalidDecl();
}
diff --git a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
index 818548c..d1ad304 100644
--- a/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
+++ b/clang/lib/Sema/SemaTemplateInstantiateDecl.cpp
@@ -3515,14 +3515,21 @@
if (Invalid)
return nullptr;
- // Note: we substitute into associated constraints later
- Expr *const UninstantiatedRequiresClause = L->getRequiresClause();
+ // FIXME: Concepts: Substitution into requires clause should only happen when
+ // checking satisfaction.
+ Expr *InstRequiresClause = nullptr;
+ if (Expr *E = L->getRequiresClause()) {
+ ExprResult Res = SemaRef.SubstExpr(E, TemplateArgs);
+ if (Res.isInvalid() || !Res.isUsable()) {
+ return nullptr;
+ }
+ InstRequiresClause = Res.get();
+ }
TemplateParameterList *InstL
= TemplateParameterList::Create(SemaRef.Context, L->getTemplateLoc(),
L->getLAngleLoc(), Params,
- L->getRAngleLoc(),
- UninstantiatedRequiresClause);
+ L->getRAngleLoc(), InstRequiresClause);
return InstL;
}
diff --git a/clang/lib/Serialization/ASTReader.cpp b/clang/lib/Serialization/ASTReader.cpp
index 20c6cbe..d879076 100644
--- a/clang/lib/Serialization/ASTReader.cpp
+++ b/clang/lib/Serialization/ASTReader.cpp
@@ -9345,9 +9345,11 @@
while (NumParams--)
Params.push_back(ReadDeclAs<NamedDecl>(F, Record, Idx));
- // TODO: Concepts
+ bool HasRequiresClause = Record[Idx++];
+ Expr *RequiresClause = HasRequiresClause ? ReadExpr(F) : nullptr;
+
TemplateParameterList *TemplateParams = TemplateParameterList::Create(
- getContext(), TemplateLoc, LAngleLoc, Params, RAngleLoc, nullptr);
+ getContext(), TemplateLoc, LAngleLoc, Params, RAngleLoc, RequiresClause);
return TemplateParams;
}
diff --git a/clang/lib/Serialization/ASTReaderDecl.cpp b/clang/lib/Serialization/ASTReaderDecl.cpp
index d906286..65d6252 100644
--- a/clang/lib/Serialization/ASTReaderDecl.cpp
+++ b/clang/lib/Serialization/ASTReaderDecl.cpp
@@ -2000,7 +2000,6 @@
DeclID PatternID = ReadDeclID();
auto *TemplatedDecl = cast_or_null<NamedDecl>(Reader.GetDecl(PatternID));
TemplateParameterList *TemplateParams = Record.readTemplateParameterList();
- // FIXME handle associated constraints
D->init(TemplatedDecl, TemplateParams);
return PatternID;
@@ -2166,7 +2165,8 @@
ClassTemplatePartialSpecializationDecl *D) {
RedeclarableResult Redecl = VisitClassTemplateSpecializationDeclImpl(D);
- D->TemplateParams = Record.readTemplateParameterList();
+ TemplateParameterList *Params = Record.readTemplateParameterList();
+ D->TemplateParams = Params;
D->ArgsAsWritten = Record.readASTTemplateArgumentListInfo();
// These are read/set from/to the first declaration.
@@ -2268,7 +2268,8 @@
VarTemplatePartialSpecializationDecl *D) {
RedeclarableResult Redecl = VisitVarTemplateSpecializationDeclImpl(D);
- D->TemplateParams = Record.readTemplateParameterList();
+ TemplateParameterList *Params = Record.readTemplateParameterList();
+ D->TemplateParams = Params;
D->ArgsAsWritten = Record.readASTTemplateArgumentListInfo();
// These are read/set from/to the first declaration.
@@ -2284,6 +2285,7 @@
D->setDeclaredWithTypename(Record.readInt());
+ // TODO: Concepts: Immediately introduced constraint
if (Record.readInt())
D->setDefaultArgument(GetTypeSourceInfo());
}
diff --git a/clang/lib/Serialization/ASTWriter.cpp b/clang/lib/Serialization/ASTWriter.cpp
index 5e9e650..aef3523 100644
--- a/clang/lib/Serialization/ASTWriter.cpp
+++ b/clang/lib/Serialization/ASTWriter.cpp
@@ -6070,10 +6070,16 @@
AddSourceLocation(TemplateParams->getTemplateLoc());
AddSourceLocation(TemplateParams->getLAngleLoc());
AddSourceLocation(TemplateParams->getRAngleLoc());
- // TODO: Concepts
+
Record->push_back(TemplateParams->size());
for (const auto &P : *TemplateParams)
AddDeclRef(P);
+ if (const Expr *RequiresClause = TemplateParams->getRequiresClause()) {
+ Record->push_back(true);
+ AddStmt(const_cast<Expr*>(RequiresClause));
+ } else {
+ Record->push_back(false);
+ }
}
/// Emit a template argument list.
diff --git a/clang/lib/Serialization/ASTWriterDecl.cpp b/clang/lib/Serialization/ASTWriterDecl.cpp
index 2c22587..039b57f 100644
--- a/clang/lib/Serialization/ASTWriterDecl.cpp
+++ b/clang/lib/Serialization/ASTWriterDecl.cpp
@@ -1608,7 +1608,7 @@
VisitTypeDecl(D);
Record.push_back(D->wasDeclaredWithTypename());
-
+ // TODO: Concepts - constrained parameters.
bool OwnsDefaultArg = D->hasDefaultArgument() &&
!D->defaultArgumentWasInherited();
Record.push_back(OwnsDefaultArg);
@@ -1638,6 +1638,7 @@
Code = serialization::DECL_EXPANDED_NON_TYPE_TEMPLATE_PARM_PACK;
} else {
+ // TODO: Concepts - constrained parameters.
// Rest of NonTypeTemplateParmDecl.
Record.push_back(D->isParameterPack());
bool OwnsDefaultArg = D->hasDefaultArgument() &&
@@ -1667,6 +1668,7 @@
Record.AddTemplateParameterList(D->getExpansionTemplateParameters(I));
Code = serialization::DECL_EXPANDED_TEMPLATE_TEMPLATE_PARM_PACK;
} else {
+ // TODO: Concepts - constrained parameters.
// Rest of TemplateTemplateParmDecl.
Record.push_back(D->isParameterPack());
bool OwnsDefaultArg = D->hasDefaultArgument() &&