Implement the sizeof...(pack) expression to compute the length of a
parameter pack.
Note that we're missing proper libclang support for the new
SizeOfPackExpr expression node.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@122813 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/ExprCXX.cpp b/lib/AST/ExprCXX.cpp
index 4592e5f..fcedb8e 100644
--- a/lib/AST/ExprCXX.cpp
+++ b/lib/AST/ExprCXX.cpp
@@ -1037,3 +1037,15 @@
Stmt::child_iterator PackExpansionExpr::child_end() {
return child_iterator(&Pattern + 1);
}
+
+SourceRange SizeOfPackExpr::getSourceRange() const {
+ return SourceRange(OperatorLoc, RParenLoc);
+}
+
+Stmt::child_iterator SizeOfPackExpr::child_begin() {
+ return child_iterator();
+}
+
+Stmt::child_iterator SizeOfPackExpr::child_end() {
+ return child_iterator();
+}
diff --git a/lib/AST/ExprClassification.cpp b/lib/AST/ExprClassification.cpp
index f437804..a9ebe6f 100644
--- a/lib/AST/ExprClassification.cpp
+++ b/lib/AST/ExprClassification.cpp
@@ -151,6 +151,7 @@
case Expr::ObjCStringLiteralClass:
case Expr::ParenListExprClass:
case Expr::InitListExprClass:
+ case Expr::SizeOfPackExprClass:
return Cl::CL_PRValue;
// Next come the complicated cases.
diff --git a/lib/AST/ExprConstant.cpp b/lib/AST/ExprConstant.cpp
index c39b398..23a4b09 100644
--- a/lib/AST/ExprConstant.cpp
+++ b/lib/AST/ExprConstant.cpp
@@ -291,6 +291,8 @@
if (Visit(E->getInit(i))) return true;
return false;
}
+
+ bool VisitSizeOfPackExpr(SizeOfPackExpr *) { return false; }
};
} // end anonymous namespace
@@ -965,7 +967,8 @@
bool VisitUnaryImag(const UnaryOperator *E);
bool VisitCXXNoexceptExpr(const CXXNoexceptExpr *E);
-
+ bool VisitSizeOfPackExpr(const SizeOfPackExpr *E);
+
private:
CharUnits GetAlignOfExpr(const Expr *E);
CharUnits GetAlignOfType(QualType T);
@@ -1761,6 +1764,10 @@
return Success(0, E);
}
+bool IntExprEvaluator::VisitSizeOfPackExpr(const SizeOfPackExpr *E) {
+ return Success(E->getPackLength(), E);
+}
+
bool IntExprEvaluator::VisitCXXNoexceptExpr(const CXXNoexceptExpr *E) {
return Success(E->getValue(), E);
}
@@ -2637,6 +2644,7 @@
case Expr::PackExpansionExprClass:
return ICEDiag(2, E->getLocStart());
+ case Expr::SizeOfPackExprClass:
case Expr::GNUNullExprClass:
// GCC considers the GNU __null value to be an integral constant expression.
return NoDiag();
diff --git a/lib/AST/StmtPrinter.cpp b/lib/AST/StmtPrinter.cpp
index cc90526..2c85043 100644
--- a/lib/AST/StmtPrinter.cpp
+++ b/lib/AST/StmtPrinter.cpp
@@ -1246,11 +1246,15 @@
OS << ")";
}
-void StmtPrinter::VisitPackExpansionExpr(clang::PackExpansionExpr *E) {
+void StmtPrinter::VisitPackExpansionExpr(PackExpansionExpr *E) {
PrintExpr(E->getPattern());
OS << "...";
}
+void StmtPrinter::VisitSizeOfPackExpr(SizeOfPackExpr *E) {
+ OS << "sizeof...(" << E->getPack()->getNameAsString() << ")";
+}
+
// Obj-C
void StmtPrinter::VisitObjCStringLiteral(ObjCStringLiteral *Node) {
diff --git a/lib/AST/StmtProfile.cpp b/lib/AST/StmtProfile.cpp
index 820eb06..ab24a69 100644
--- a/lib/AST/StmtProfile.cpp
+++ b/lib/AST/StmtProfile.cpp
@@ -836,6 +836,11 @@
VisitExpr(S);
}
+void StmtProfiler::VisitSizeOfPackExpr(SizeOfPackExpr *S) {
+ VisitExpr(S);
+ VisitDecl(S->getPack());
+}
+
void StmtProfiler::VisitOpaqueValueExpr(OpaqueValueExpr *E) {
VisitExpr(E);
}
diff --git a/lib/Parse/ParseExpr.cpp b/lib/Parse/ParseExpr.cpp
index be5c7d7..7133b61 100644
--- a/lib/Parse/ParseExpr.cpp
+++ b/lib/Parse/ParseExpr.cpp
@@ -444,6 +444,7 @@
/// unary-operator cast-expression
/// 'sizeof' unary-expression
/// 'sizeof' '(' type-name ')'
+/// [C++0x] 'sizeof' '...' '(' identifier ')'
/// [GNU] '__alignof' unary-expression
/// [GNU] '__alignof' '(' type-name ')'
/// [C++0x] 'alignof' '(' type-id ')'
@@ -1291,6 +1292,7 @@
/// unary-expression: [C99 6.5.3]
/// 'sizeof' unary-expression
/// 'sizeof' '(' type-name ')'
+/// [C++0x] 'sizeof' '...' '(' identifier ')'
/// [GNU] '__alignof' unary-expression
/// [GNU] '__alignof' '(' type-name ')'
/// [C++0x] 'alignof' '(' type-id ')'
@@ -1301,6 +1303,46 @@
Token OpTok = Tok;
ConsumeToken();
+ // [C++0x] 'sizeof' '...' '(' identifier ')'
+ if (Tok.is(tok::ellipsis) && OpTok.is(tok::kw_sizeof)) {
+ SourceLocation EllipsisLoc = ConsumeToken();
+ SourceLocation LParenLoc, RParenLoc;
+ IdentifierInfo *Name = 0;
+ SourceLocation NameLoc;
+ if (Tok.is(tok::l_paren)) {
+ LParenLoc = ConsumeParen();
+ if (Tok.is(tok::identifier)) {
+ Name = Tok.getIdentifierInfo();
+ NameLoc = ConsumeToken();
+ RParenLoc = MatchRHSPunctuation(tok::r_paren, LParenLoc);
+ if (RParenLoc.isInvalid())
+ RParenLoc = PP.getLocForEndOfToken(NameLoc);
+ } else {
+ Diag(Tok, diag::err_expected_parameter_pack);
+ SkipUntil(tok::r_paren);
+ }
+ } else if (Tok.is(tok::identifier)) {
+ Name = Tok.getIdentifierInfo();
+ NameLoc = ConsumeToken();
+ LParenLoc = PP.getLocForEndOfToken(EllipsisLoc);
+ RParenLoc = PP.getLocForEndOfToken(NameLoc);
+ Diag(LParenLoc, diag::err_paren_sizeof_parameter_pack)
+ << Name
+ << FixItHint::CreateInsertion(LParenLoc, "(")
+ << FixItHint::CreateInsertion(RParenLoc, ")");
+ } else {
+ Diag(Tok, diag::err_sizeof_parameter_pack);
+ }
+
+ if (!Name)
+ return ExprError();
+
+ return Actions.ActOnSizeofParameterPackExpr(getCurScope(),
+ OpTok.getLocation(),
+ *Name, NameLoc,
+ RParenLoc);
+ }
+
bool isCastExpr;
ParsedType CastTy;
SourceRange CastRange;
diff --git a/lib/Sema/SemaTemplateVariadic.cpp b/lib/Sema/SemaTemplateVariadic.cpp
index 92df1fd..4e01ec2 100644
--- a/lib/Sema/SemaTemplateVariadic.cpp
+++ b/lib/Sema/SemaTemplateVariadic.cpp
@@ -10,6 +10,7 @@
//===----------------------------------------------------------------------===/
#include "clang/Sema/Sema.h"
+#include "clang/Sema/Lookup.h"
#include "clang/Sema/ParsedTemplate.h"
#include "clang/Sema/SemaInternal.h"
#include "clang/Sema/Template.h"
@@ -533,3 +534,71 @@
return false;
}
+
+/// \brief Called when an expression computing the size of a parameter pack
+/// is parsed.
+///
+/// \code
+/// template<typename ...Types> struct count {
+/// static const unsigned value = sizeof...(Types);
+/// };
+/// \endcode
+///
+//
+/// \param OpLoc The location of the "sizeof" keyword.
+/// \param Name The name of the parameter pack whose size will be determined.
+/// \param NameLoc The source location of the name of the parameter pack.
+/// \param RParenLoc The location of the closing parentheses.
+ExprResult Sema::ActOnSizeofParameterPackExpr(Scope *S,
+ SourceLocation OpLoc,
+ IdentifierInfo &Name,
+ SourceLocation NameLoc,
+ SourceLocation RParenLoc) {
+ // C++0x [expr.sizeof]p5:
+ // The identifier in a sizeof... expression shall name a parameter pack.
+
+ LookupResult R(*this, &Name, NameLoc, LookupOrdinaryName);
+ LookupName(R, S);
+
+ NamedDecl *ParameterPack = 0;
+ switch (R.getResultKind()) {
+ case LookupResult::Found:
+ ParameterPack = R.getFoundDecl();
+ break;
+
+ case LookupResult::NotFound:
+ case LookupResult::NotFoundInCurrentInstantiation:
+ if (DeclarationName CorrectedName = CorrectTypo(R, S, 0, 0, false,
+ CTC_NoKeywords)) {
+ // FIXME: Variadic templates function parameter packs.
+ if (NamedDecl *CorrectedResult = R.getAsSingle<NamedDecl>())
+ if (CorrectedResult->isTemplateParameterPack()) {
+ ParameterPack = CorrectedResult;
+ Diag(NameLoc, diag::err_sizeof_pack_no_pack_name_suggest)
+ << &Name << CorrectedName
+ << FixItHint::CreateReplacement(NameLoc,
+ CorrectedName.getAsString());
+ Diag(ParameterPack->getLocation(), diag::note_parameter_pack_here)
+ << CorrectedName;
+ }
+ }
+
+ case LookupResult::FoundOverloaded:
+ case LookupResult::FoundUnresolvedValue:
+ break;
+
+ case LookupResult::Ambiguous:
+ DiagnoseAmbiguousLookup(R);
+ return ExprError();
+ }
+
+ // FIXME: Variadic templates function parameter packs.
+ if (!ParameterPack || !ParameterPack->isTemplateParameterPack()) {
+ Diag(NameLoc, diag::err_sizeof_pack_no_pack_name)
+ << &Name;
+ return ExprError();
+ }
+
+ return new (Context) SizeOfPackExpr(Context.getSizeType(), OpLoc,
+ ParameterPack, NameLoc, RParenLoc);
+}
diff --git a/lib/Sema/TreeTransform.h b/lib/Sema/TreeTransform.h
index c38902a..27fbf93 100644
--- a/lib/Sema/TreeTransform.h
+++ b/lib/Sema/TreeTransform.h
@@ -1913,6 +1913,16 @@
return SemaRef.BuildCXXNoexceptExpr(Range.getBegin(), Arg, Range.getEnd());
}
+ /// \brief Build a new expression to compute the length of a parameter pack.
+ ExprResult RebuildSizeOfPackExpr(SourceLocation OperatorLoc, NamedDecl *Pack,
+ SourceLocation PackLoc,
+ SourceLocation RParenLoc,
+ unsigned Length) {
+ return new (SemaRef.Context) SizeOfPackExpr(SemaRef.Context.getSizeType(),
+ OperatorLoc, Pack, PackLoc,
+ RParenLoc, Length);
+ }
+
/// \brief Build a new Objective-C @encode expression.
///
/// By default, performs semantic analysis to build the new expression.
@@ -6499,7 +6509,36 @@
llvm_unreachable("pack expansion expression in unhandled context");
return ExprError();
}
+
+template<typename Derived>
+ExprResult
+TreeTransform<Derived>::TransformSizeOfPackExpr(SizeOfPackExpr *E) {
+ // If E is not value-dependent, then nothing will change when we transform it.
+ // Note: This is an instantiation-centric view.
+ if (!E->isValueDependent())
+ return SemaRef.Owned(E);
+
+ // Note: None of the implementations of TryExpandParameterPacks can ever
+ // produce a diagnostic when given only a single unexpanded parameter pack,
+ // so
+ UnexpandedParameterPack Unexpanded(E->getPack(), E->getPackLoc());
+ bool ShouldExpand = false;
+ unsigned NumExpansions = 0;
+ if (getDerived().TryExpandParameterPacks(E->getOperatorLoc(), E->getPackLoc(),
+ &Unexpanded, 1,
+ ShouldExpand, NumExpansions))
+ return ExprError();
+ if (!ShouldExpand)
+ return SemaRef.Owned(E);
+
+ // We now know the length of the parameter pack, so build a new expression
+ // that stores that length.
+ return getDerived().RebuildSizeOfPackExpr(E->getOperatorLoc(), E->getPack(),
+ E->getPackLoc(), E->getRParenLoc(),
+ NumExpansions);
+}
+
template<typename Derived>
ExprResult
TreeTransform<Derived>::TransformObjCStringLiteral(ObjCStringLiteral *E) {
diff --git a/lib/Serialization/ASTReaderStmt.cpp b/lib/Serialization/ASTReaderStmt.cpp
index 4703c63..5ed6f8e 100644
--- a/lib/Serialization/ASTReaderStmt.cpp
+++ b/lib/Serialization/ASTReaderStmt.cpp
@@ -177,6 +177,7 @@
void VisitBinaryTypeTraitExpr(BinaryTypeTraitExpr *E);
void VisitCXXNoexceptExpr(CXXNoexceptExpr *E);
void VisitPackExpansionExpr(PackExpansionExpr *E);
+ void VisitSizeOfPackExpr(SizeOfPackExpr *E);
void VisitOpaqueValueExpr(OpaqueValueExpr *E);
};
@@ -1294,6 +1295,15 @@
E->Pattern = Reader.ReadSubExpr();
}
+void ASTStmtReader::VisitSizeOfPackExpr(SizeOfPackExpr *E) {
+ VisitExpr(E);
+ E->OperatorLoc = ReadSourceLocation(Record, Idx);
+ E->PackLoc = ReadSourceLocation(Record, Idx);
+ E->RParenLoc = ReadSourceLocation(Record, Idx);
+ E->Length = Record[Idx++];
+ E->Pack = cast_or_null<NamedDecl>(Reader.GetDecl(Record[Idx++]));
+}
+
void ASTStmtReader::VisitOpaqueValueExpr(OpaqueValueExpr *E) {
VisitExpr(E);
}
@@ -1820,6 +1830,10 @@
S = new (Context) PackExpansionExpr(Empty);
break;
+ case EXPR_SIZEOF_PACK:
+ S = new (Context) SizeOfPackExpr(Empty);
+ break;
+
case EXPR_OPAQUE_VALUE:
S = new (Context) OpaqueValueExpr(Empty);
break;
diff --git a/lib/Serialization/ASTWriterStmt.cpp b/lib/Serialization/ASTWriterStmt.cpp
index 27261db..af066bb 100644
--- a/lib/Serialization/ASTWriterStmt.cpp
+++ b/lib/Serialization/ASTWriterStmt.cpp
@@ -151,6 +151,7 @@
void VisitBinaryTypeTraitExpr(BinaryTypeTraitExpr *E);
void VisitCXXNoexceptExpr(CXXNoexceptExpr *E);
void VisitPackExpansionExpr(PackExpansionExpr *E);
+ void VisitSizeOfPackExpr(SizeOfPackExpr *E);
void VisitOpaqueValueExpr(OpaqueValueExpr *E);
};
}
@@ -1303,6 +1304,16 @@
Code = serialization::EXPR_PACK_EXPANSION;
}
+void ASTStmtWriter::VisitSizeOfPackExpr(SizeOfPackExpr *E) {
+ VisitExpr(E);
+ Writer.AddSourceLocation(E->OperatorLoc, Record);
+ Writer.AddSourceLocation(E->PackLoc, Record);
+ Writer.AddSourceLocation(E->RParenLoc, Record);
+ Record.push_back(E->Length);
+ Writer.AddDeclRef(E->Pack, Record);
+ Code = serialization::EXPR_SIZEOF_PACK;
+}
+
void ASTStmtWriter::VisitOpaqueValueExpr(OpaqueValueExpr *E) {
VisitExpr(E);
Code = serialization::EXPR_OPAQUE_VALUE;