Check in LLVM r95781.
diff --git a/lib/Sema/SemaTemplateDeduction.cpp b/lib/Sema/SemaTemplateDeduction.cpp
new file mode 100644
index 0000000..df4d4a8
--- /dev/null
+++ b/lib/Sema/SemaTemplateDeduction.cpp
@@ -0,0 +1,2509 @@
+//===------- SemaTemplateDeduction.cpp - Template Argument Deduction ------===/
+//
+// 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 argument deduction.
+//
+//===----------------------------------------------------------------------===/
+
+#include "Sema.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/DeclTemplate.h"
+#include "clang/AST/StmtVisitor.h"
+#include "clang/AST/Expr.h"
+#include "clang/AST/ExprCXX.h"
+#include "clang/Parse/DeclSpec.h"
+#include <algorithm>
+
+namespace clang {
+ /// \brief Various flags that control template argument deduction.
+ ///
+ /// These flags can be bitwise-OR'd together.
+ enum TemplateDeductionFlags {
+ /// \brief No template argument deduction flags, which indicates the
+ /// strictest results for template argument deduction (as used for, e.g.,
+ /// matching class template partial specializations).
+ TDF_None = 0,
+ /// \brief Within template argument deduction from a function call, we are
+ /// matching with a parameter type for which the original parameter was
+ /// a reference.
+ TDF_ParamWithReferenceType = 0x1,
+ /// \brief Within template argument deduction from a function call, we
+ /// are matching in a case where we ignore cv-qualifiers.
+ TDF_IgnoreQualifiers = 0x02,
+ /// \brief Within template argument deduction from a function call,
+ /// we are matching in a case where we can perform template argument
+ /// deduction from a template-id of a derived class of the argument type.
+ TDF_DerivedClass = 0x04,
+ /// \brief Allow non-dependent types to differ, e.g., when performing
+ /// template argument deduction from a function call where conversions
+ /// may apply.
+ TDF_SkipNonDependent = 0x08
+ };
+}
+
+using namespace clang;
+
+static Sema::TemplateDeductionResult
+DeduceTemplateArguments(Sema &S,
+ TemplateParameterList *TemplateParams,
+ const TemplateArgument &Param,
+ const TemplateArgument &Arg,
+ Sema::TemplateDeductionInfo &Info,
+ llvm::SmallVectorImpl<TemplateArgument> &Deduced);
+
+/// \brief If the given expression is of a form that permits the deduction
+/// of a non-type template parameter, return the declaration of that
+/// non-type template parameter.
+static NonTypeTemplateParmDecl *getDeducedParameterFromExpr(Expr *E) {
+ if (ImplicitCastExpr *IC = dyn_cast<ImplicitCastExpr>(E))
+ E = IC->getSubExpr();
+
+ if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E))
+ return dyn_cast<NonTypeTemplateParmDecl>(DRE->getDecl());
+
+ return 0;
+}
+
+/// \brief Deduce the value of the given non-type template parameter
+/// from the given constant.
+static Sema::TemplateDeductionResult
+DeduceNonTypeTemplateArgument(Sema &S,
+ NonTypeTemplateParmDecl *NTTP,
+ llvm::APSInt Value,
+ Sema::TemplateDeductionInfo &Info,
+ llvm::SmallVectorImpl<TemplateArgument> &Deduced) {
+ assert(NTTP->getDepth() == 0 &&
+ "Cannot deduce non-type template argument with depth > 0");
+
+ if (Deduced[NTTP->getIndex()].isNull()) {
+ QualType T = NTTP->getType();
+
+ // FIXME: Make sure we didn't overflow our data type!
+ unsigned AllowedBits = S.Context.getTypeSize(T);
+ if (Value.getBitWidth() != AllowedBits)
+ Value.extOrTrunc(AllowedBits);
+ Value.setIsSigned(T->isSignedIntegerType());
+
+ Deduced[NTTP->getIndex()] = TemplateArgument(Value, T);
+ return Sema::TDK_Success;
+ }
+
+ assert(Deduced[NTTP->getIndex()].getKind() == TemplateArgument::Integral);
+
+ // If the template argument was previously deduced to a negative value,
+ // then our deduction fails.
+ const llvm::APSInt *PrevValuePtr = Deduced[NTTP->getIndex()].getAsIntegral();
+ if (PrevValuePtr->isNegative()) {
+ Info.Param = NTTP;
+ Info.FirstArg = Deduced[NTTP->getIndex()];
+ Info.SecondArg = TemplateArgument(Value, NTTP->getType());
+ return Sema::TDK_Inconsistent;
+ }
+
+ llvm::APSInt PrevValue = *PrevValuePtr;
+ if (Value.getBitWidth() > PrevValue.getBitWidth())
+ PrevValue.zext(Value.getBitWidth());
+ else if (Value.getBitWidth() < PrevValue.getBitWidth())
+ Value.zext(PrevValue.getBitWidth());
+
+ if (Value != PrevValue) {
+ Info.Param = NTTP;
+ Info.FirstArg = Deduced[NTTP->getIndex()];
+ Info.SecondArg = TemplateArgument(Value, NTTP->getType());
+ return Sema::TDK_Inconsistent;
+ }
+
+ return Sema::TDK_Success;
+}
+
+/// \brief Deduce the value of the given non-type template parameter
+/// from the given type- or value-dependent expression.
+///
+/// \returns true if deduction succeeded, false otherwise.
+static Sema::TemplateDeductionResult
+DeduceNonTypeTemplateArgument(Sema &S,
+ NonTypeTemplateParmDecl *NTTP,
+ Expr *Value,
+ Sema::TemplateDeductionInfo &Info,
+ llvm::SmallVectorImpl<TemplateArgument> &Deduced) {
+ assert(NTTP->getDepth() == 0 &&
+ "Cannot deduce non-type template argument with depth > 0");
+ assert((Value->isTypeDependent() || Value->isValueDependent()) &&
+ "Expression template argument must be type- or value-dependent.");
+
+ if (Deduced[NTTP->getIndex()].isNull()) {
+ // FIXME: Clone the Value?
+ Deduced[NTTP->getIndex()] = TemplateArgument(Value);
+ return Sema::TDK_Success;
+ }
+
+ if (Deduced[NTTP->getIndex()].getKind() == TemplateArgument::Integral) {
+ // Okay, we deduced a constant in one case and a dependent expression
+ // in another case. FIXME: Later, we will check that instantiating the
+ // dependent expression gives us the constant value.
+ return Sema::TDK_Success;
+ }
+
+ if (Deduced[NTTP->getIndex()].getKind() == TemplateArgument::Expression) {
+ // Compare the expressions for equality
+ llvm::FoldingSetNodeID ID1, ID2;
+ Deduced[NTTP->getIndex()].getAsExpr()->Profile(ID1, S.Context, true);
+ Value->Profile(ID2, S.Context, true);
+ if (ID1 == ID2)
+ return Sema::TDK_Success;
+
+ // FIXME: Fill in argument mismatch information
+ return Sema::TDK_NonDeducedMismatch;
+ }
+
+ return Sema::TDK_Success;
+}
+
+/// \brief Deduce the value of the given non-type template parameter
+/// from the given declaration.
+///
+/// \returns true if deduction succeeded, false otherwise.
+static Sema::TemplateDeductionResult
+DeduceNonTypeTemplateArgument(Sema &S,
+ NonTypeTemplateParmDecl *NTTP,
+ Decl *D,
+ Sema::TemplateDeductionInfo &Info,
+ llvm::SmallVectorImpl<TemplateArgument> &Deduced) {
+ assert(NTTP->getDepth() == 0 &&
+ "Cannot deduce non-type template argument with depth > 0");
+
+ if (Deduced[NTTP->getIndex()].isNull()) {
+ Deduced[NTTP->getIndex()] = TemplateArgument(D->getCanonicalDecl());
+ return Sema::TDK_Success;
+ }
+
+ if (Deduced[NTTP->getIndex()].getKind() == TemplateArgument::Expression) {
+ // Okay, we deduced a declaration in one case and a dependent expression
+ // in another case.
+ return Sema::TDK_Success;
+ }
+
+ if (Deduced[NTTP->getIndex()].getKind() == TemplateArgument::Declaration) {
+ // Compare the declarations for equality
+ if (Deduced[NTTP->getIndex()].getAsDecl()->getCanonicalDecl() ==
+ D->getCanonicalDecl())
+ return Sema::TDK_Success;
+
+ // FIXME: Fill in argument mismatch information
+ return Sema::TDK_NonDeducedMismatch;
+ }
+
+ return Sema::TDK_Success;
+}
+
+static Sema::TemplateDeductionResult
+DeduceTemplateArguments(Sema &S,
+ TemplateParameterList *TemplateParams,
+ TemplateName Param,
+ TemplateName Arg,
+ Sema::TemplateDeductionInfo &Info,
+ llvm::SmallVectorImpl<TemplateArgument> &Deduced) {
+ TemplateDecl *ParamDecl = Param.getAsTemplateDecl();
+ if (!ParamDecl) {
+ // The parameter type is dependent and is not a template template parameter,
+ // so there is nothing that we can deduce.
+ return Sema::TDK_Success;
+ }
+
+ if (TemplateTemplateParmDecl *TempParam
+ = dyn_cast<TemplateTemplateParmDecl>(ParamDecl)) {
+ // Bind the template template parameter to the given template name.
+ TemplateArgument &ExistingArg = Deduced[TempParam->getIndex()];
+ if (ExistingArg.isNull()) {
+ // This is the first deduction for this template template parameter.
+ ExistingArg = TemplateArgument(S.Context.getCanonicalTemplateName(Arg));
+ return Sema::TDK_Success;
+ }
+
+ // Verify that the previous binding matches this deduction.
+ assert(ExistingArg.getKind() == TemplateArgument::Template);
+ if (S.Context.hasSameTemplateName(ExistingArg.getAsTemplate(), Arg))
+ return Sema::TDK_Success;
+
+ // Inconsistent deduction.
+ Info.Param = TempParam;
+ Info.FirstArg = ExistingArg;
+ Info.SecondArg = TemplateArgument(Arg);
+ return Sema::TDK_Inconsistent;
+ }
+
+ // Verify that the two template names are equivalent.
+ if (S.Context.hasSameTemplateName(Param, Arg))
+ return Sema::TDK_Success;
+
+ // Mismatch of non-dependent template parameter to argument.
+ Info.FirstArg = TemplateArgument(Param);
+ Info.SecondArg = TemplateArgument(Arg);
+ return Sema::TDK_NonDeducedMismatch;
+}
+
+/// \brief Deduce the template arguments by comparing the template parameter
+/// type (which is a template-id) with the template argument type.
+///
+/// \param S the Sema
+///
+/// \param TemplateParams the template parameters that we are deducing
+///
+/// \param Param the parameter type
+///
+/// \param Arg the argument type
+///
+/// \param Info information about the template argument deduction itself
+///
+/// \param Deduced the deduced template arguments
+///
+/// \returns the result of template argument deduction so far. Note that a
+/// "success" result means that template argument deduction has not yet failed,
+/// but it may still fail, later, for other reasons.
+static Sema::TemplateDeductionResult
+DeduceTemplateArguments(Sema &S,
+ TemplateParameterList *TemplateParams,
+ const TemplateSpecializationType *Param,
+ QualType Arg,
+ Sema::TemplateDeductionInfo &Info,
+ llvm::SmallVectorImpl<TemplateArgument> &Deduced) {
+ assert(Arg.isCanonical() && "Argument type must be canonical");
+
+ // Check whether the template argument is a dependent template-id.
+ if (const TemplateSpecializationType *SpecArg
+ = dyn_cast<TemplateSpecializationType>(Arg)) {
+ // Perform template argument deduction for the template name.
+ if (Sema::TemplateDeductionResult Result
+ = DeduceTemplateArguments(S, TemplateParams,
+ Param->getTemplateName(),
+ SpecArg->getTemplateName(),
+ Info, Deduced))
+ return Result;
+
+
+ // Perform template argument deduction on each template
+ // argument.
+ unsigned NumArgs = std::min(SpecArg->getNumArgs(), Param->getNumArgs());
+ for (unsigned I = 0; I != NumArgs; ++I)
+ if (Sema::TemplateDeductionResult Result
+ = DeduceTemplateArguments(S, TemplateParams,
+ Param->getArg(I),
+ SpecArg->getArg(I),
+ Info, Deduced))
+ return Result;
+
+ return Sema::TDK_Success;
+ }
+
+ // If the argument type is a class template specialization, we
+ // perform template argument deduction using its template
+ // arguments.
+ const RecordType *RecordArg = dyn_cast<RecordType>(Arg);
+ if (!RecordArg)
+ return Sema::TDK_NonDeducedMismatch;
+
+ ClassTemplateSpecializationDecl *SpecArg
+ = dyn_cast<ClassTemplateSpecializationDecl>(RecordArg->getDecl());
+ if (!SpecArg)
+ return Sema::TDK_NonDeducedMismatch;
+
+ // Perform template argument deduction for the template name.
+ if (Sema::TemplateDeductionResult Result
+ = DeduceTemplateArguments(S,
+ TemplateParams,
+ Param->getTemplateName(),
+ TemplateName(SpecArg->getSpecializedTemplate()),
+ Info, Deduced))
+ return Result;
+
+ unsigned NumArgs = Param->getNumArgs();
+ const TemplateArgumentList &ArgArgs = SpecArg->getTemplateArgs();
+ if (NumArgs != ArgArgs.size())
+ return Sema::TDK_NonDeducedMismatch;
+
+ for (unsigned I = 0; I != NumArgs; ++I)
+ if (Sema::TemplateDeductionResult Result
+ = DeduceTemplateArguments(S, TemplateParams,
+ Param->getArg(I),
+ ArgArgs.get(I),
+ Info, Deduced))
+ return Result;
+
+ return Sema::TDK_Success;
+}
+
+/// \brief Deduce the template arguments by comparing the parameter type and
+/// the argument type (C++ [temp.deduct.type]).
+///
+/// \param S the semantic analysis object within which we are deducing
+///
+/// \param TemplateParams the template parameters that we are deducing
+///
+/// \param ParamIn the parameter type
+///
+/// \param ArgIn the argument type
+///
+/// \param Info information about the template argument deduction itself
+///
+/// \param Deduced the deduced template arguments
+///
+/// \param TDF bitwise OR of the TemplateDeductionFlags bits that describe
+/// how template argument deduction is performed.
+///
+/// \returns the result of template argument deduction so far. Note that a
+/// "success" result means that template argument deduction has not yet failed,
+/// but it may still fail, later, for other reasons.
+static Sema::TemplateDeductionResult
+DeduceTemplateArguments(Sema &S,
+ TemplateParameterList *TemplateParams,
+ QualType ParamIn, QualType ArgIn,
+ Sema::TemplateDeductionInfo &Info,
+ llvm::SmallVectorImpl<TemplateArgument> &Deduced,
+ unsigned TDF) {
+ // We only want to look at the canonical types, since typedefs and
+ // sugar are not part of template argument deduction.
+ QualType Param = S.Context.getCanonicalType(ParamIn);
+ QualType Arg = S.Context.getCanonicalType(ArgIn);
+
+ // C++0x [temp.deduct.call]p4 bullet 1:
+ // - If the original P is a reference type, the deduced A (i.e., the type
+ // referred to by the reference) can be more cv-qualified than the
+ // transformed A.
+ if (TDF & TDF_ParamWithReferenceType) {
+ Qualifiers Quals;
+ QualType UnqualParam = S.Context.getUnqualifiedArrayType(Param, Quals);
+ Quals.setCVRQualifiers(Quals.getCVRQualifiers() &
+ Arg.getCVRQualifiersThroughArrayTypes());
+ Param = S.Context.getQualifiedType(UnqualParam, Quals);
+ }
+
+ // If the parameter type is not dependent, there is nothing to deduce.
+ if (!Param->isDependentType()) {
+ if (!(TDF & TDF_SkipNonDependent) && Param != Arg) {
+
+ return Sema::TDK_NonDeducedMismatch;
+ }
+
+ return Sema::TDK_Success;
+ }
+
+ // C++ [temp.deduct.type]p9:
+ // A template type argument T, a template template argument TT or a
+ // template non-type argument i can be deduced if P and A have one of
+ // the following forms:
+ //
+ // T
+ // cv-list T
+ if (const TemplateTypeParmType *TemplateTypeParm
+ = Param->getAs<TemplateTypeParmType>()) {
+ unsigned Index = TemplateTypeParm->getIndex();
+ bool RecanonicalizeArg = false;
+
+ // If the argument type is an array type, move the qualifiers up to the
+ // top level, so they can be matched with the qualifiers on the parameter.
+ // FIXME: address spaces, ObjC GC qualifiers
+ if (isa<ArrayType>(Arg)) {
+ Qualifiers Quals;
+ Arg = S.Context.getUnqualifiedArrayType(Arg, Quals);
+ if (Quals) {
+ Arg = S.Context.getQualifiedType(Arg, Quals);
+ RecanonicalizeArg = true;
+ }
+ }
+
+ // The argument type can not be less qualified than the parameter
+ // type.
+ if (Param.isMoreQualifiedThan(Arg) && !(TDF & TDF_IgnoreQualifiers)) {
+ Info.Param = cast<TemplateTypeParmDecl>(TemplateParams->getParam(Index));
+ Info.FirstArg = Deduced[Index];
+ Info.SecondArg = TemplateArgument(Arg);
+ return Sema::TDK_InconsistentQuals;
+ }
+
+ assert(TemplateTypeParm->getDepth() == 0 && "Can't deduce with depth > 0");
+ assert(Arg != S.Context.OverloadTy && "Unresolved overloaded function");
+ QualType DeducedType = Arg;
+ DeducedType.removeCVRQualifiers(Param.getCVRQualifiers());
+ if (RecanonicalizeArg)
+ DeducedType = S.Context.getCanonicalType(DeducedType);
+
+ if (Deduced[Index].isNull())
+ Deduced[Index] = TemplateArgument(DeducedType);
+ else {
+ // C++ [temp.deduct.type]p2:
+ // [...] If type deduction cannot be done for any P/A pair, or if for
+ // any pair the deduction leads to more than one possible set of
+ // deduced values, or if different pairs yield different deduced
+ // values, or if any template argument remains neither deduced nor
+ // explicitly specified, template argument deduction fails.
+ if (Deduced[Index].getAsType() != DeducedType) {
+ Info.Param
+ = cast<TemplateTypeParmDecl>(TemplateParams->getParam(Index));
+ Info.FirstArg = Deduced[Index];
+ Info.SecondArg = TemplateArgument(Arg);
+ return Sema::TDK_Inconsistent;
+ }
+ }
+ return Sema::TDK_Success;
+ }
+
+ // Set up the template argument deduction information for a failure.
+ Info.FirstArg = TemplateArgument(ParamIn);
+ Info.SecondArg = TemplateArgument(ArgIn);
+
+ // Check the cv-qualifiers on the parameter and argument types.
+ if (!(TDF & TDF_IgnoreQualifiers)) {
+ if (TDF & TDF_ParamWithReferenceType) {
+ if (Param.isMoreQualifiedThan(Arg))
+ return Sema::TDK_NonDeducedMismatch;
+ } else {
+ if (Param.getCVRQualifiers() != Arg.getCVRQualifiers())
+ return Sema::TDK_NonDeducedMismatch;
+ }
+ }
+
+ switch (Param->getTypeClass()) {
+ // No deduction possible for these types
+ case Type::Builtin:
+ return Sema::TDK_NonDeducedMismatch;
+
+ // T *
+ case Type::Pointer: {
+ const PointerType *PointerArg = Arg->getAs<PointerType>();
+ if (!PointerArg)
+ return Sema::TDK_NonDeducedMismatch;
+
+ unsigned SubTDF = TDF & (TDF_IgnoreQualifiers | TDF_DerivedClass);
+ return DeduceTemplateArguments(S, TemplateParams,
+ cast<PointerType>(Param)->getPointeeType(),
+ PointerArg->getPointeeType(),
+ Info, Deduced, SubTDF);
+ }
+
+ // T &
+ case Type::LValueReference: {
+ const LValueReferenceType *ReferenceArg = Arg->getAs<LValueReferenceType>();
+ if (!ReferenceArg)
+ return Sema::TDK_NonDeducedMismatch;
+
+ return DeduceTemplateArguments(S, TemplateParams,
+ cast<LValueReferenceType>(Param)->getPointeeType(),
+ ReferenceArg->getPointeeType(),
+ Info, Deduced, 0);
+ }
+
+ // T && [C++0x]
+ case Type::RValueReference: {
+ const RValueReferenceType *ReferenceArg = Arg->getAs<RValueReferenceType>();
+ if (!ReferenceArg)
+ return Sema::TDK_NonDeducedMismatch;
+
+ return DeduceTemplateArguments(S, TemplateParams,
+ cast<RValueReferenceType>(Param)->getPointeeType(),
+ ReferenceArg->getPointeeType(),
+ Info, Deduced, 0);
+ }
+
+ // T [] (implied, but not stated explicitly)
+ case Type::IncompleteArray: {
+ const IncompleteArrayType *IncompleteArrayArg =
+ S.Context.getAsIncompleteArrayType(Arg);
+ if (!IncompleteArrayArg)
+ return Sema::TDK_NonDeducedMismatch;
+
+ return DeduceTemplateArguments(S, TemplateParams,
+ S.Context.getAsIncompleteArrayType(Param)->getElementType(),
+ IncompleteArrayArg->getElementType(),
+ Info, Deduced, 0);
+ }
+
+ // T [integer-constant]
+ case Type::ConstantArray: {
+ const ConstantArrayType *ConstantArrayArg =
+ S.Context.getAsConstantArrayType(Arg);
+ if (!ConstantArrayArg)
+ return Sema::TDK_NonDeducedMismatch;
+
+ const ConstantArrayType *ConstantArrayParm =
+ S.Context.getAsConstantArrayType(Param);
+ if (ConstantArrayArg->getSize() != ConstantArrayParm->getSize())
+ return Sema::TDK_NonDeducedMismatch;
+
+ return DeduceTemplateArguments(S, TemplateParams,
+ ConstantArrayParm->getElementType(),
+ ConstantArrayArg->getElementType(),
+ Info, Deduced, 0);
+ }
+
+ // type [i]
+ case Type::DependentSizedArray: {
+ const ArrayType *ArrayArg = S.Context.getAsArrayType(Arg);
+ if (!ArrayArg)
+ return Sema::TDK_NonDeducedMismatch;
+
+ // Check the element type of the arrays
+ const DependentSizedArrayType *DependentArrayParm
+ = S.Context.getAsDependentSizedArrayType(Param);
+ if (Sema::TemplateDeductionResult Result
+ = DeduceTemplateArguments(S, TemplateParams,
+ DependentArrayParm->getElementType(),
+ ArrayArg->getElementType(),
+ Info, Deduced, 0))
+ return Result;
+
+ // Determine the array bound is something we can deduce.
+ NonTypeTemplateParmDecl *NTTP
+ = getDeducedParameterFromExpr(DependentArrayParm->getSizeExpr());
+ if (!NTTP)
+ return Sema::TDK_Success;
+
+ // We can perform template argument deduction for the given non-type
+ // template parameter.
+ assert(NTTP->getDepth() == 0 &&
+ "Cannot deduce non-type template argument at depth > 0");
+ if (const ConstantArrayType *ConstantArrayArg
+ = dyn_cast<ConstantArrayType>(ArrayArg)) {
+ llvm::APSInt Size(ConstantArrayArg->getSize());
+ return DeduceNonTypeTemplateArgument(S, NTTP, Size,
+ Info, Deduced);
+ }
+ if (const DependentSizedArrayType *DependentArrayArg
+ = dyn_cast<DependentSizedArrayType>(ArrayArg))
+ return DeduceNonTypeTemplateArgument(S, NTTP,
+ DependentArrayArg->getSizeExpr(),
+ Info, Deduced);
+
+ // Incomplete type does not match a dependently-sized array type
+ return Sema::TDK_NonDeducedMismatch;
+ }
+
+ // type(*)(T)
+ // T(*)()
+ // T(*)(T)
+ case Type::FunctionProto: {
+ const FunctionProtoType *FunctionProtoArg =
+ dyn_cast<FunctionProtoType>(Arg);
+ if (!FunctionProtoArg)
+ return Sema::TDK_NonDeducedMismatch;
+
+ const FunctionProtoType *FunctionProtoParam =
+ cast<FunctionProtoType>(Param);
+
+ if (FunctionProtoParam->getTypeQuals() !=
+ FunctionProtoArg->getTypeQuals())
+ return Sema::TDK_NonDeducedMismatch;
+
+ if (FunctionProtoParam->getNumArgs() != FunctionProtoArg->getNumArgs())
+ return Sema::TDK_NonDeducedMismatch;
+
+ if (FunctionProtoParam->isVariadic() != FunctionProtoArg->isVariadic())
+ return Sema::TDK_NonDeducedMismatch;
+
+ // Check return types.
+ if (Sema::TemplateDeductionResult Result
+ = DeduceTemplateArguments(S, TemplateParams,
+ FunctionProtoParam->getResultType(),
+ FunctionProtoArg->getResultType(),
+ Info, Deduced, 0))
+ return Result;
+
+ for (unsigned I = 0, N = FunctionProtoParam->getNumArgs(); I != N; ++I) {
+ // Check argument types.
+ if (Sema::TemplateDeductionResult Result
+ = DeduceTemplateArguments(S, TemplateParams,
+ FunctionProtoParam->getArgType(I),
+ FunctionProtoArg->getArgType(I),
+ Info, Deduced, 0))
+ return Result;
+ }
+
+ return Sema::TDK_Success;
+ }
+
+ // template-name<T> (where template-name refers to a class template)
+ // template-name<i>
+ // TT<T>
+ // TT<i>
+ // TT<>
+ case Type::TemplateSpecialization: {
+ const TemplateSpecializationType *SpecParam
+ = cast<TemplateSpecializationType>(Param);
+
+ // Try to deduce template arguments from the template-id.
+ Sema::TemplateDeductionResult Result
+ = DeduceTemplateArguments(S, TemplateParams, SpecParam, Arg,
+ Info, Deduced);
+
+ if (Result && (TDF & TDF_DerivedClass)) {
+ // C++ [temp.deduct.call]p3b3:
+ // If P is a class, and P has the form template-id, then A can be a
+ // derived class of the deduced A. Likewise, if P is a pointer to a
+ // class of the form template-id, A can be a pointer to a derived
+ // class pointed to by the deduced A.
+ //
+ // More importantly:
+ // These alternatives are considered only if type deduction would
+ // otherwise fail.
+ if (const RecordType *RecordT = Arg->getAs<RecordType>()) {
+ // We cannot inspect base classes as part of deduction when the type
+ // is incomplete, so either instantiate any templates necessary to
+ // complete the type, or skip over it if it cannot be completed.
+ if (S.RequireCompleteType(Info.getLocation(), Arg, 0))
+ return Result;
+
+ // Use data recursion to crawl through the list of base classes.
+ // Visited contains the set of nodes we have already visited, while
+ // ToVisit is our stack of records that we still need to visit.
+ llvm::SmallPtrSet<const RecordType *, 8> Visited;
+ llvm::SmallVector<const RecordType *, 8> ToVisit;
+ ToVisit.push_back(RecordT);
+ bool Successful = false;
+ while (!ToVisit.empty()) {
+ // Retrieve the next class in the inheritance hierarchy.
+ const RecordType *NextT = ToVisit.back();
+ ToVisit.pop_back();
+
+ // If we have already seen this type, skip it.
+ if (!Visited.insert(NextT))
+ continue;
+
+ // If this is a base class, try to perform template argument
+ // deduction from it.
+ if (NextT != RecordT) {
+ Sema::TemplateDeductionResult BaseResult
+ = DeduceTemplateArguments(S, TemplateParams, SpecParam,
+ QualType(NextT, 0), Info, Deduced);
+
+ // If template argument deduction for this base was successful,
+ // note that we had some success.
+ if (BaseResult == Sema::TDK_Success)
+ Successful = true;
+ }
+
+ // Visit base classes
+ CXXRecordDecl *Next = cast<CXXRecordDecl>(NextT->getDecl());
+ for (CXXRecordDecl::base_class_iterator Base = Next->bases_begin(),
+ BaseEnd = Next->bases_end();
+ Base != BaseEnd; ++Base) {
+ assert(Base->getType()->isRecordType() &&
+ "Base class that isn't a record?");
+ ToVisit.push_back(Base->getType()->getAs<RecordType>());
+ }
+ }
+
+ if (Successful)
+ return Sema::TDK_Success;
+ }
+
+ }
+
+ return Result;
+ }
+
+ // T type::*
+ // T T::*
+ // T (type::*)()
+ // type (T::*)()
+ // type (type::*)(T)
+ // type (T::*)(T)
+ // T (type::*)(T)
+ // T (T::*)()
+ // T (T::*)(T)
+ case Type::MemberPointer: {
+ const MemberPointerType *MemPtrParam = cast<MemberPointerType>(Param);
+ const MemberPointerType *MemPtrArg = dyn_cast<MemberPointerType>(Arg);
+ if (!MemPtrArg)
+ return Sema::TDK_NonDeducedMismatch;
+
+ if (Sema::TemplateDeductionResult Result
+ = DeduceTemplateArguments(S, TemplateParams,
+ MemPtrParam->getPointeeType(),
+ MemPtrArg->getPointeeType(),
+ Info, Deduced,
+ TDF & TDF_IgnoreQualifiers))
+ return Result;
+
+ return DeduceTemplateArguments(S, TemplateParams,
+ QualType(MemPtrParam->getClass(), 0),
+ QualType(MemPtrArg->getClass(), 0),
+ Info, Deduced, 0);
+ }
+
+ // (clang extension)
+ //
+ // type(^)(T)
+ // T(^)()
+ // T(^)(T)
+ case Type::BlockPointer: {
+ const BlockPointerType *BlockPtrParam = cast<BlockPointerType>(Param);
+ const BlockPointerType *BlockPtrArg = dyn_cast<BlockPointerType>(Arg);
+
+ if (!BlockPtrArg)
+ return Sema::TDK_NonDeducedMismatch;
+
+ return DeduceTemplateArguments(S, TemplateParams,
+ BlockPtrParam->getPointeeType(),
+ BlockPtrArg->getPointeeType(), Info,
+ Deduced, 0);
+ }
+
+ case Type::TypeOfExpr:
+ case Type::TypeOf:
+ case Type::Typename:
+ // No template argument deduction for these types
+ return Sema::TDK_Success;
+
+ default:
+ break;
+ }
+
+ // FIXME: Many more cases to go (to go).
+ return Sema::TDK_Success;
+}
+
+static Sema::TemplateDeductionResult
+DeduceTemplateArguments(Sema &S,
+ TemplateParameterList *TemplateParams,
+ const TemplateArgument &Param,
+ const TemplateArgument &Arg,
+ Sema::TemplateDeductionInfo &Info,
+ llvm::SmallVectorImpl<TemplateArgument> &Deduced) {
+ switch (Param.getKind()) {
+ case TemplateArgument::Null:
+ assert(false && "Null template argument in parameter list");
+ break;
+
+ case TemplateArgument::Type:
+ if (Arg.getKind() == TemplateArgument::Type)
+ return DeduceTemplateArguments(S, TemplateParams, Param.getAsType(),
+ Arg.getAsType(), Info, Deduced, 0);
+ Info.FirstArg = Param;
+ Info.SecondArg = Arg;
+ return Sema::TDK_NonDeducedMismatch;
+
+ case TemplateArgument::Template:
+ if (Arg.getKind() == TemplateArgument::Template)
+ return DeduceTemplateArguments(S, TemplateParams,
+ Param.getAsTemplate(),
+ Arg.getAsTemplate(), Info, Deduced);
+ Info.FirstArg = Param;
+ Info.SecondArg = Arg;
+ return Sema::TDK_NonDeducedMismatch;
+
+ case TemplateArgument::Declaration:
+ if (Arg.getKind() == TemplateArgument::Declaration &&
+ Param.getAsDecl()->getCanonicalDecl() ==
+ Arg.getAsDecl()->getCanonicalDecl())
+ return Sema::TDK_Success;
+
+ Info.FirstArg = Param;
+ Info.SecondArg = Arg;
+ return Sema::TDK_NonDeducedMismatch;
+
+ case TemplateArgument::Integral:
+ if (Arg.getKind() == TemplateArgument::Integral) {
+ // FIXME: Zero extension + sign checking here?
+ if (*Param.getAsIntegral() == *Arg.getAsIntegral())
+ return Sema::TDK_Success;
+
+ Info.FirstArg = Param;
+ Info.SecondArg = Arg;
+ return Sema::TDK_NonDeducedMismatch;
+ }
+
+ if (Arg.getKind() == TemplateArgument::Expression) {
+ Info.FirstArg = Param;
+ Info.SecondArg = Arg;
+ return Sema::TDK_NonDeducedMismatch;
+ }
+
+ assert(false && "Type/value mismatch");
+ Info.FirstArg = Param;
+ Info.SecondArg = Arg;
+ return Sema::TDK_NonDeducedMismatch;
+
+ case TemplateArgument::Expression: {
+ if (NonTypeTemplateParmDecl *NTTP
+ = getDeducedParameterFromExpr(Param.getAsExpr())) {
+ if (Arg.getKind() == TemplateArgument::Integral)
+ // FIXME: Sign problems here
+ return DeduceNonTypeTemplateArgument(S, NTTP,
+ *Arg.getAsIntegral(),
+ Info, Deduced);
+ if (Arg.getKind() == TemplateArgument::Expression)
+ return DeduceNonTypeTemplateArgument(S, NTTP, Arg.getAsExpr(),
+ Info, Deduced);
+ if (Arg.getKind() == TemplateArgument::Declaration)
+ return DeduceNonTypeTemplateArgument(S, NTTP, Arg.getAsDecl(),
+ Info, Deduced);
+
+ assert(false && "Type/value mismatch");
+ Info.FirstArg = Param;
+ Info.SecondArg = Arg;
+ return Sema::TDK_NonDeducedMismatch;
+ }
+
+ // Can't deduce anything, but that's okay.
+ return Sema::TDK_Success;
+ }
+ case TemplateArgument::Pack:
+ assert(0 && "FIXME: Implement!");
+ break;
+ }
+
+ return Sema::TDK_Success;
+}
+
+static Sema::TemplateDeductionResult
+DeduceTemplateArguments(Sema &S,
+ TemplateParameterList *TemplateParams,
+ const TemplateArgumentList &ParamList,
+ const TemplateArgumentList &ArgList,
+ Sema::TemplateDeductionInfo &Info,
+ llvm::SmallVectorImpl<TemplateArgument> &Deduced) {
+ assert(ParamList.size() == ArgList.size());
+ for (unsigned I = 0, N = ParamList.size(); I != N; ++I) {
+ if (Sema::TemplateDeductionResult Result
+ = DeduceTemplateArguments(S, TemplateParams,
+ ParamList[I], ArgList[I],
+ Info, Deduced))
+ return Result;
+ }
+ return Sema::TDK_Success;
+}
+
+/// \brief Determine whether two template arguments are the same.
+static bool isSameTemplateArg(ASTContext &Context,
+ const TemplateArgument &X,
+ const TemplateArgument &Y) {
+ if (X.getKind() != Y.getKind())
+ return false;
+
+ switch (X.getKind()) {
+ case TemplateArgument::Null:
+ assert(false && "Comparing NULL template argument");
+ break;
+
+ case TemplateArgument::Type:
+ return Context.getCanonicalType(X.getAsType()) ==
+ Context.getCanonicalType(Y.getAsType());
+
+ case TemplateArgument::Declaration:
+ return X.getAsDecl()->getCanonicalDecl() ==
+ Y.getAsDecl()->getCanonicalDecl();
+
+ case TemplateArgument::Template:
+ return Context.getCanonicalTemplateName(X.getAsTemplate())
+ .getAsVoidPointer() ==
+ Context.getCanonicalTemplateName(Y.getAsTemplate())
+ .getAsVoidPointer();
+
+ case TemplateArgument::Integral:
+ return *X.getAsIntegral() == *Y.getAsIntegral();
+
+ case TemplateArgument::Expression: {
+ llvm::FoldingSetNodeID XID, YID;
+ X.getAsExpr()->Profile(XID, Context, true);
+ Y.getAsExpr()->Profile(YID, Context, true);
+ return XID == YID;
+ }
+
+ case TemplateArgument::Pack:
+ if (X.pack_size() != Y.pack_size())
+ return false;
+
+ for (TemplateArgument::pack_iterator XP = X.pack_begin(),
+ XPEnd = X.pack_end(),
+ YP = Y.pack_begin();
+ XP != XPEnd; ++XP, ++YP)
+ if (!isSameTemplateArg(Context, *XP, *YP))
+ return false;
+
+ return true;
+ }
+
+ return false;
+}
+
+/// \brief Helper function to build a TemplateParameter when we don't
+/// know its type statically.
+static TemplateParameter makeTemplateParameter(Decl *D) {
+ if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(D))
+ return TemplateParameter(TTP);
+ else if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(D))
+ return TemplateParameter(NTTP);
+
+ return TemplateParameter(cast<TemplateTemplateParmDecl>(D));
+}
+
+/// \brief Perform template argument deduction to determine whether
+/// the given template arguments match the given class template
+/// partial specialization per C++ [temp.class.spec.match].
+Sema::TemplateDeductionResult
+Sema::DeduceTemplateArguments(ClassTemplatePartialSpecializationDecl *Partial,
+ const TemplateArgumentList &TemplateArgs,
+ TemplateDeductionInfo &Info) {
+ // C++ [temp.class.spec.match]p2:
+ // A partial specialization matches a given actual template
+ // argument list if the template arguments of the partial
+ // specialization can be deduced from the actual template argument
+ // list (14.8.2).
+ SFINAETrap Trap(*this);
+ llvm::SmallVector<TemplateArgument, 4> Deduced;
+ Deduced.resize(Partial->getTemplateParameters()->size());
+ if (TemplateDeductionResult Result
+ = ::DeduceTemplateArguments(*this,
+ Partial->getTemplateParameters(),
+ Partial->getTemplateArgs(),
+ TemplateArgs, Info, Deduced))
+ return Result;
+
+ InstantiatingTemplate Inst(*this, Partial->getLocation(), Partial,
+ Deduced.data(), Deduced.size());
+ if (Inst)
+ return TDK_InstantiationDepth;
+
+ // C++ [temp.deduct.type]p2:
+ // [...] or if any template argument remains neither deduced nor
+ // explicitly specified, template argument deduction fails.
+ TemplateArgumentListBuilder Builder(Partial->getTemplateParameters(),
+ Deduced.size());
+ for (unsigned I = 0, N = Deduced.size(); I != N; ++I) {
+ if (Deduced[I].isNull()) {
+ Decl *Param
+ = const_cast<NamedDecl *>(
+ Partial->getTemplateParameters()->getParam(I));
+ if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(Param))
+ Info.Param = TTP;
+ else if (NonTypeTemplateParmDecl *NTTP
+ = dyn_cast<NonTypeTemplateParmDecl>(Param))
+ Info.Param = NTTP;
+ else
+ Info.Param = cast<TemplateTemplateParmDecl>(Param);
+ return TDK_Incomplete;
+ }
+
+ Builder.Append(Deduced[I]);
+ }
+
+ // Form the template argument list from the deduced template arguments.
+ TemplateArgumentList *DeducedArgumentList
+ = new (Context) TemplateArgumentList(Context, Builder, /*TakeArgs=*/true);
+ Info.reset(DeducedArgumentList);
+
+ // Substitute the deduced template arguments into the template
+ // arguments of the class template partial specialization, and
+ // verify that the instantiated template arguments are both valid
+ // and are equivalent to the template arguments originally provided
+ // to the class template.
+ ClassTemplateDecl *ClassTemplate = Partial->getSpecializedTemplate();
+ const TemplateArgumentLoc *PartialTemplateArgs
+ = Partial->getTemplateArgsAsWritten();
+ unsigned N = Partial->getNumTemplateArgsAsWritten();
+
+ // Note that we don't provide the langle and rangle locations.
+ TemplateArgumentListInfo InstArgs;
+
+ for (unsigned I = 0; I != N; ++I) {
+ Decl *Param = const_cast<NamedDecl *>(
+ ClassTemplate->getTemplateParameters()->getParam(I));
+ TemplateArgumentLoc InstArg;
+ if (Subst(PartialTemplateArgs[I], InstArg,
+ MultiLevelTemplateArgumentList(*DeducedArgumentList))) {
+ Info.Param = makeTemplateParameter(Param);
+ Info.FirstArg = PartialTemplateArgs[I].getArgument();
+ return TDK_SubstitutionFailure;
+ }
+ InstArgs.addArgument(InstArg);
+ }
+
+ TemplateArgumentListBuilder ConvertedInstArgs(
+ ClassTemplate->getTemplateParameters(), N);
+
+ if (CheckTemplateArgumentList(ClassTemplate, Partial->getLocation(),
+ InstArgs, false, ConvertedInstArgs)) {
+ // FIXME: fail with more useful information?
+ return TDK_SubstitutionFailure;
+ }
+
+ for (unsigned I = 0, E = ConvertedInstArgs.flatSize(); I != E; ++I) {
+ TemplateArgument InstArg = ConvertedInstArgs.getFlatArguments()[I];
+
+ Decl *Param = const_cast<NamedDecl *>(
+ ClassTemplate->getTemplateParameters()->getParam(I));
+
+ if (InstArg.getKind() == TemplateArgument::Expression) {
+ // When the argument is an expression, check the expression result
+ // against the actual template parameter to get down to the canonical
+ // template argument.
+ Expr *InstExpr = InstArg.getAsExpr();
+ if (NonTypeTemplateParmDecl *NTTP
+ = dyn_cast<NonTypeTemplateParmDecl>(Param)) {
+ if (CheckTemplateArgument(NTTP, NTTP->getType(), InstExpr, InstArg)) {
+ Info.Param = makeTemplateParameter(Param);
+ Info.FirstArg = Partial->getTemplateArgs()[I];
+ return TDK_SubstitutionFailure;
+ }
+ }
+ }
+
+ if (!isSameTemplateArg(Context, TemplateArgs[I], InstArg)) {
+ Info.Param = makeTemplateParameter(Param);
+ Info.FirstArg = TemplateArgs[I];
+ Info.SecondArg = InstArg;
+ return TDK_NonDeducedMismatch;
+ }
+ }
+
+ if (Trap.hasErrorOccurred())
+ return TDK_SubstitutionFailure;
+
+ return TDK_Success;
+}
+
+/// \brief Determine whether the given type T is a simple-template-id type.
+static bool isSimpleTemplateIdType(QualType T) {
+ if (const TemplateSpecializationType *Spec
+ = T->getAs<TemplateSpecializationType>())
+ return Spec->getTemplateName().getAsTemplateDecl() != 0;
+
+ return false;
+}
+
+/// \brief Substitute the explicitly-provided template arguments into the
+/// given function template according to C++ [temp.arg.explicit].
+///
+/// \param FunctionTemplate the function template into which the explicit
+/// template arguments will be substituted.
+///
+/// \param ExplicitTemplateArguments the explicitly-specified template
+/// arguments.
+///
+/// \param Deduced the deduced template arguments, which will be populated
+/// with the converted and checked explicit template arguments.
+///
+/// \param ParamTypes will be populated with the instantiated function
+/// parameters.
+///
+/// \param FunctionType if non-NULL, the result type of the function template
+/// will also be instantiated and the pointed-to value will be updated with
+/// the instantiated function type.
+///
+/// \param Info if substitution fails for any reason, this object will be
+/// populated with more information about the failure.
+///
+/// \returns TDK_Success if substitution was successful, or some failure
+/// condition.
+Sema::TemplateDeductionResult
+Sema::SubstituteExplicitTemplateArguments(
+ FunctionTemplateDecl *FunctionTemplate,
+ const TemplateArgumentListInfo &ExplicitTemplateArgs,
+ llvm::SmallVectorImpl<TemplateArgument> &Deduced,
+ llvm::SmallVectorImpl<QualType> &ParamTypes,
+ QualType *FunctionType,
+ TemplateDeductionInfo &Info) {
+ FunctionDecl *Function = FunctionTemplate->getTemplatedDecl();
+ TemplateParameterList *TemplateParams
+ = FunctionTemplate->getTemplateParameters();
+
+ if (ExplicitTemplateArgs.size() == 0) {
+ // No arguments to substitute; just copy over the parameter types and
+ // fill in the function type.
+ for (FunctionDecl::param_iterator P = Function->param_begin(),
+ PEnd = Function->param_end();
+ P != PEnd;
+ ++P)
+ ParamTypes.push_back((*P)->getType());
+
+ if (FunctionType)
+ *FunctionType = Function->getType();
+ return TDK_Success;
+ }
+
+ // Substitution of the explicit template arguments into a function template
+ /// is a SFINAE context. Trap any errors that might occur.
+ SFINAETrap Trap(*this);
+
+ // C++ [temp.arg.explicit]p3:
+ // Template arguments that are present shall be specified in the
+ // declaration order of their corresponding template-parameters. The
+ // template argument list shall not specify more template-arguments than
+ // there are corresponding template-parameters.
+ TemplateArgumentListBuilder Builder(TemplateParams,
+ ExplicitTemplateArgs.size());
+
+ // Enter a new template instantiation context where we check the
+ // explicitly-specified template arguments against this function template,
+ // and then substitute them into the function parameter types.
+ InstantiatingTemplate Inst(*this, FunctionTemplate->getLocation(),
+ FunctionTemplate, Deduced.data(), Deduced.size(),
+ ActiveTemplateInstantiation::ExplicitTemplateArgumentSubstitution);
+ if (Inst)
+ return TDK_InstantiationDepth;
+
+ if (CheckTemplateArgumentList(FunctionTemplate,
+ SourceLocation(),
+ ExplicitTemplateArgs,
+ true,
+ Builder) || Trap.hasErrorOccurred())
+ return TDK_InvalidExplicitArguments;
+
+ // Form the template argument list from the explicitly-specified
+ // template arguments.
+ TemplateArgumentList *ExplicitArgumentList
+ = new (Context) TemplateArgumentList(Context, Builder, /*TakeArgs=*/true);
+ Info.reset(ExplicitArgumentList);
+
+ // Instantiate the types of each of the function parameters given the
+ // explicitly-specified template arguments.
+ for (FunctionDecl::param_iterator P = Function->param_begin(),
+ PEnd = Function->param_end();
+ P != PEnd;
+ ++P) {
+ QualType ParamType
+ = SubstType((*P)->getType(),
+ MultiLevelTemplateArgumentList(*ExplicitArgumentList),
+ (*P)->getLocation(), (*P)->getDeclName());
+ if (ParamType.isNull() || Trap.hasErrorOccurred())
+ return TDK_SubstitutionFailure;
+
+ ParamTypes.push_back(ParamType);
+ }
+
+ // If the caller wants a full function type back, instantiate the return
+ // type and form that function type.
+ if (FunctionType) {
+ // FIXME: exception-specifications?
+ const FunctionProtoType *Proto
+ = Function->getType()->getAs<FunctionProtoType>();
+ assert(Proto && "Function template does not have a prototype?");
+
+ QualType ResultType
+ = SubstType(Proto->getResultType(),
+ MultiLevelTemplateArgumentList(*ExplicitArgumentList),
+ Function->getTypeSpecStartLoc(),
+ Function->getDeclName());
+ if (ResultType.isNull() || Trap.hasErrorOccurred())
+ return TDK_SubstitutionFailure;
+
+ *FunctionType = BuildFunctionType(ResultType,
+ ParamTypes.data(), ParamTypes.size(),
+ Proto->isVariadic(),
+ Proto->getTypeQuals(),
+ Function->getLocation(),
+ Function->getDeclName());
+ if (FunctionType->isNull() || Trap.hasErrorOccurred())
+ return TDK_SubstitutionFailure;
+ }
+
+ // C++ [temp.arg.explicit]p2:
+ // Trailing template arguments that can be deduced (14.8.2) may be
+ // omitted from the list of explicit template-arguments. If all of the
+ // template arguments can be deduced, they may all be omitted; in this
+ // case, the empty template argument list <> itself may also be omitted.
+ //
+ // Take all of the explicitly-specified arguments and put them into the
+ // set of deduced template arguments.
+ Deduced.reserve(TemplateParams->size());
+ for (unsigned I = 0, N = ExplicitArgumentList->size(); I != N; ++I)
+ Deduced.push_back(ExplicitArgumentList->get(I));
+
+ return TDK_Success;
+}
+
+/// \brief Finish template argument deduction for a function template,
+/// checking the deduced template arguments for completeness and forming
+/// the function template specialization.
+Sema::TemplateDeductionResult
+Sema::FinishTemplateArgumentDeduction(FunctionTemplateDecl *FunctionTemplate,
+ llvm::SmallVectorImpl<TemplateArgument> &Deduced,
+ FunctionDecl *&Specialization,
+ TemplateDeductionInfo &Info) {
+ TemplateParameterList *TemplateParams
+ = FunctionTemplate->getTemplateParameters();
+
+ // Template argument deduction for function templates in a SFINAE context.
+ // Trap any errors that might occur.
+ SFINAETrap Trap(*this);
+
+ // Enter a new template instantiation context while we instantiate the
+ // actual function declaration.
+ InstantiatingTemplate Inst(*this, FunctionTemplate->getLocation(),
+ FunctionTemplate, Deduced.data(), Deduced.size(),
+ ActiveTemplateInstantiation::DeducedTemplateArgumentSubstitution);
+ if (Inst)
+ return TDK_InstantiationDepth;
+
+ // C++ [temp.deduct.type]p2:
+ // [...] or if any template argument remains neither deduced nor
+ // explicitly specified, template argument deduction fails.
+ TemplateArgumentListBuilder Builder(TemplateParams, Deduced.size());
+ for (unsigned I = 0, N = Deduced.size(); I != N; ++I) {
+ if (!Deduced[I].isNull()) {
+ Builder.Append(Deduced[I]);
+ continue;
+ }
+
+ // Substitute into the default template argument, if available.
+ NamedDecl *Param = FunctionTemplate->getTemplateParameters()->getParam(I);
+ TemplateArgumentLoc DefArg
+ = SubstDefaultTemplateArgumentIfAvailable(FunctionTemplate,
+ FunctionTemplate->getLocation(),
+ FunctionTemplate->getSourceRange().getEnd(),
+ Param,
+ Builder);
+
+ // If there was no default argument, deduction is incomplete.
+ if (DefArg.getArgument().isNull()) {
+ Info.Param = makeTemplateParameter(
+ const_cast<NamedDecl *>(TemplateParams->getParam(I)));
+ return TDK_Incomplete;
+ }
+
+ // Check whether we can actually use the default argument.
+ if (CheckTemplateArgument(Param, DefArg,
+ FunctionTemplate,
+ FunctionTemplate->getLocation(),
+ FunctionTemplate->getSourceRange().getEnd(),
+ Builder)) {
+ Info.Param = makeTemplateParameter(
+ const_cast<NamedDecl *>(TemplateParams->getParam(I)));
+ return TDK_SubstitutionFailure;
+ }
+
+ // If we get here, we successfully used the default template argument.
+ }
+
+ // Form the template argument list from the deduced template arguments.
+ TemplateArgumentList *DeducedArgumentList
+ = new (Context) TemplateArgumentList(Context, Builder, /*TakeArgs=*/true);
+ Info.reset(DeducedArgumentList);
+
+ // Substitute the deduced template arguments into the function template
+ // declaration to produce the function template specialization.
+ Specialization = cast_or_null<FunctionDecl>(
+ SubstDecl(FunctionTemplate->getTemplatedDecl(),
+ FunctionTemplate->getDeclContext(),
+ MultiLevelTemplateArgumentList(*DeducedArgumentList)));
+ if (!Specialization)
+ return TDK_SubstitutionFailure;
+
+ assert(Specialization->getPrimaryTemplate()->getCanonicalDecl() ==
+ FunctionTemplate->getCanonicalDecl());
+
+ // If the template argument list is owned by the function template
+ // specialization, release it.
+ if (Specialization->getTemplateSpecializationArgs() == DeducedArgumentList)
+ Info.take();
+
+ // There may have been an error that did not prevent us from constructing a
+ // declaration. Mark the declaration invalid and return with a substitution
+ // failure.
+ if (Trap.hasErrorOccurred()) {
+ Specialization->setInvalidDecl(true);
+ return TDK_SubstitutionFailure;
+ }
+
+ return TDK_Success;
+}
+
+static QualType GetTypeOfFunction(ASTContext &Context,
+ bool isAddressOfOperand,
+ FunctionDecl *Fn) {
+ if (!isAddressOfOperand) return Fn->getType();
+ if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn))
+ if (Method->isInstance())
+ return Context.getMemberPointerType(Fn->getType(),
+ Context.getTypeDeclType(Method->getParent()).getTypePtr());
+ return Context.getPointerType(Fn->getType());
+}
+
+/// Apply the deduction rules for overload sets.
+///
+/// \return the null type if this argument should be treated as an
+/// undeduced context
+static QualType
+ResolveOverloadForDeduction(Sema &S, TemplateParameterList *TemplateParams,
+ Expr *Arg, QualType ParamType) {
+ llvm::PointerIntPair<OverloadExpr*,1> R = OverloadExpr::find(Arg);
+
+ bool isAddressOfOperand = bool(R.getInt());
+ OverloadExpr *Ovl = R.getPointer();
+
+ // If there were explicit template arguments, we can only find
+ // something via C++ [temp.arg.explicit]p3, i.e. if the arguments
+ // unambiguously name a full specialization.
+ if (Ovl->hasExplicitTemplateArgs()) {
+ // But we can still look for an explicit specialization.
+ if (FunctionDecl *ExplicitSpec
+ = S.ResolveSingleFunctionTemplateSpecialization(Ovl))
+ return GetTypeOfFunction(S.Context, isAddressOfOperand, ExplicitSpec);
+ return QualType();
+ }
+
+ // C++0x [temp.deduct.call]p6:
+ // When P is a function type, pointer to function type, or pointer
+ // to member function type:
+
+ if (!ParamType->isFunctionType() &&
+ !ParamType->isFunctionPointerType() &&
+ !ParamType->isMemberFunctionPointerType())
+ return QualType();
+
+ QualType Match;
+ for (UnresolvedSetIterator I = Ovl->decls_begin(),
+ E = Ovl->decls_end(); I != E; ++I) {
+ NamedDecl *D = (*I)->getUnderlyingDecl();
+
+ // - If the argument is an overload set containing one or more
+ // function templates, the parameter is treated as a
+ // non-deduced context.
+ if (isa<FunctionTemplateDecl>(D))
+ return QualType();
+
+ FunctionDecl *Fn = cast<FunctionDecl>(D);
+ QualType ArgType = GetTypeOfFunction(S.Context, isAddressOfOperand, Fn);
+
+ // - If the argument is an overload set (not containing function
+ // templates), trial argument deduction is attempted using each
+ // of the members of the set. If deduction succeeds for only one
+ // of the overload set members, that member is used as the
+ // argument value for the deduction. If deduction succeeds for
+ // more than one member of the overload set the parameter is
+ // treated as a non-deduced context.
+
+ // We do all of this in a fresh context per C++0x [temp.deduct.type]p2:
+ // Type deduction is done independently for each P/A pair, and
+ // the deduced template argument values are then combined.
+ // So we do not reject deductions which were made elsewhere.
+ llvm::SmallVector<TemplateArgument, 8> Deduced(TemplateParams->size());
+ Sema::TemplateDeductionInfo Info(S.Context, Ovl->getNameLoc());
+ unsigned TDF = 0;
+
+ Sema::TemplateDeductionResult Result
+ = DeduceTemplateArguments(S, TemplateParams,
+ ParamType, ArgType,
+ Info, Deduced, TDF);
+ if (Result) continue;
+ if (!Match.isNull()) return QualType();
+ Match = ArgType;
+ }
+
+ return Match;
+}
+
+/// \brief Perform template argument deduction from a function call
+/// (C++ [temp.deduct.call]).
+///
+/// \param FunctionTemplate the function template for which we are performing
+/// template argument deduction.
+///
+/// \param ExplicitTemplateArguments the explicit template arguments provided
+/// for this call.
+///
+/// \param Args the function call arguments
+///
+/// \param NumArgs the number of arguments in Args
+///
+/// \param Name the name of the function being called. This is only significant
+/// when the function template is a conversion function template, in which
+/// case this routine will also perform template argument deduction based on
+/// the function to which
+///
+/// \param Specialization if template argument deduction was successful,
+/// this will be set to the function template specialization produced by
+/// template argument deduction.
+///
+/// \param Info the argument will be updated to provide additional information
+/// about template argument deduction.
+///
+/// \returns the result of template argument deduction.
+Sema::TemplateDeductionResult
+Sema::DeduceTemplateArguments(FunctionTemplateDecl *FunctionTemplate,
+ const TemplateArgumentListInfo *ExplicitTemplateArgs,
+ Expr **Args, unsigned NumArgs,
+ FunctionDecl *&Specialization,
+ TemplateDeductionInfo &Info) {
+ FunctionDecl *Function = FunctionTemplate->getTemplatedDecl();
+
+ // C++ [temp.deduct.call]p1:
+ // Template argument deduction is done by comparing each function template
+ // parameter type (call it P) with the type of the corresponding argument
+ // of the call (call it A) as described below.
+ unsigned CheckArgs = NumArgs;
+ if (NumArgs < Function->getMinRequiredArguments())
+ return TDK_TooFewArguments;
+ else if (NumArgs > Function->getNumParams()) {
+ const FunctionProtoType *Proto
+ = Function->getType()->getAs<FunctionProtoType>();
+ if (!Proto->isVariadic())
+ return TDK_TooManyArguments;
+
+ CheckArgs = Function->getNumParams();
+ }
+
+ // The types of the parameters from which we will perform template argument
+ // deduction.
+ TemplateParameterList *TemplateParams
+ = FunctionTemplate->getTemplateParameters();
+ llvm::SmallVector<TemplateArgument, 4> Deduced;
+ llvm::SmallVector<QualType, 4> ParamTypes;
+ if (ExplicitTemplateArgs) {
+ TemplateDeductionResult Result =
+ SubstituteExplicitTemplateArguments(FunctionTemplate,
+ *ExplicitTemplateArgs,
+ Deduced,
+ ParamTypes,
+ 0,
+ Info);
+ if (Result)
+ return Result;
+ } else {
+ // Just fill in the parameter types from the function declaration.
+ for (unsigned I = 0; I != CheckArgs; ++I)
+ ParamTypes.push_back(Function->getParamDecl(I)->getType());
+ }
+
+ // Deduce template arguments from the function parameters.
+ Deduced.resize(TemplateParams->size());
+ for (unsigned I = 0; I != CheckArgs; ++I) {
+ QualType ParamType = ParamTypes[I];
+ QualType ArgType = Args[I]->getType();
+
+ // Overload sets usually make this parameter an undeduced
+ // context, but there are sometimes special circumstances.
+ if (ArgType == Context.OverloadTy) {
+ ArgType = ResolveOverloadForDeduction(*this, TemplateParams,
+ Args[I], ParamType);
+ if (ArgType.isNull())
+ continue;
+ }
+
+ // C++ [temp.deduct.call]p2:
+ // If P is not a reference type:
+ QualType CanonParamType = Context.getCanonicalType(ParamType);
+ bool ParamWasReference = isa<ReferenceType>(CanonParamType);
+ if (!ParamWasReference) {
+ // - If A is an array type, the pointer type produced by the
+ // array-to-pointer standard conversion (4.2) is used in place of
+ // A for type deduction; otherwise,
+ if (ArgType->isArrayType())
+ ArgType = Context.getArrayDecayedType(ArgType);
+ // - If A is a function type, the pointer type produced by the
+ // function-to-pointer standard conversion (4.3) is used in place
+ // of A for type deduction; otherwise,
+ else if (ArgType->isFunctionType())
+ ArgType = Context.getPointerType(ArgType);
+ else {
+ // - If A is a cv-qualified type, the top level cv-qualifiers of A’s
+ // type are ignored for type deduction.
+ QualType CanonArgType = Context.getCanonicalType(ArgType);
+ if (CanonArgType.getLocalCVRQualifiers())
+ ArgType = CanonArgType.getLocalUnqualifiedType();
+ }
+ }
+
+ // C++0x [temp.deduct.call]p3:
+ // If P is a cv-qualified type, the top level cv-qualifiers of P’s type
+ // are ignored for type deduction.
+ if (CanonParamType.getLocalCVRQualifiers())
+ ParamType = CanonParamType.getLocalUnqualifiedType();
+ if (const ReferenceType *ParamRefType = ParamType->getAs<ReferenceType>()) {
+ // [...] If P is a reference type, the type referred to by P is used
+ // for type deduction.
+ ParamType = ParamRefType->getPointeeType();
+
+ // [...] If P is of the form T&&, where T is a template parameter, and
+ // the argument is an lvalue, the type A& is used in place of A for
+ // type deduction.
+ if (isa<RValueReferenceType>(ParamRefType) &&
+ ParamRefType->getAs<TemplateTypeParmType>() &&
+ Args[I]->isLvalue(Context) == Expr::LV_Valid)
+ ArgType = Context.getLValueReferenceType(ArgType);
+ }
+
+ // C++0x [temp.deduct.call]p4:
+ // In general, the deduction process attempts to find template argument
+ // values that will make the deduced A identical to A (after the type A
+ // is transformed as described above). [...]
+ unsigned TDF = TDF_SkipNonDependent;
+
+ // - If the original P is a reference type, the deduced A (i.e., the
+ // type referred to by the reference) can be more cv-qualified than
+ // the transformed A.
+ if (ParamWasReference)
+ TDF |= TDF_ParamWithReferenceType;
+ // - The transformed A can be another pointer or pointer to member
+ // type that can be converted to the deduced A via a qualification
+ // conversion (4.4).
+ if (ArgType->isPointerType() || ArgType->isMemberPointerType())
+ TDF |= TDF_IgnoreQualifiers;
+ // - If P is a class and P has the form simple-template-id, then the
+ // transformed A can be a derived class of the deduced A. Likewise,
+ // if P is a pointer to a class of the form simple-template-id, the
+ // transformed A can be a pointer to a derived class pointed to by
+ // the deduced A.
+ if (isSimpleTemplateIdType(ParamType) ||
+ (isa<PointerType>(ParamType) &&
+ isSimpleTemplateIdType(
+ ParamType->getAs<PointerType>()->getPointeeType())))
+ TDF |= TDF_DerivedClass;
+
+ if (TemplateDeductionResult Result
+ = ::DeduceTemplateArguments(*this, TemplateParams,
+ ParamType, ArgType, Info, Deduced,
+ TDF))
+ return Result;
+
+ // FIXME: we need to check that the deduced A is the same as A,
+ // modulo the various allowed differences.
+ }
+
+ return FinishTemplateArgumentDeduction(FunctionTemplate, Deduced,
+ Specialization, Info);
+}
+
+/// \brief Deduce template arguments when taking the address of a function
+/// template (C++ [temp.deduct.funcaddr]) or matching a specialization to
+/// a template.
+///
+/// \param FunctionTemplate the function template for which we are performing
+/// template argument deduction.
+///
+/// \param ExplicitTemplateArguments the explicitly-specified template
+/// arguments.
+///
+/// \param ArgFunctionType the function type that will be used as the
+/// "argument" type (A) when performing template argument deduction from the
+/// function template's function type. This type may be NULL, if there is no
+/// argument type to compare against, in C++0x [temp.arg.explicit]p3.
+///
+/// \param Specialization if template argument deduction was successful,
+/// this will be set to the function template specialization produced by
+/// template argument deduction.
+///
+/// \param Info the argument will be updated to provide additional information
+/// about template argument deduction.
+///
+/// \returns the result of template argument deduction.
+Sema::TemplateDeductionResult
+Sema::DeduceTemplateArguments(FunctionTemplateDecl *FunctionTemplate,
+ const TemplateArgumentListInfo *ExplicitTemplateArgs,
+ QualType ArgFunctionType,
+ FunctionDecl *&Specialization,
+ TemplateDeductionInfo &Info) {
+ FunctionDecl *Function = FunctionTemplate->getTemplatedDecl();
+ TemplateParameterList *TemplateParams
+ = FunctionTemplate->getTemplateParameters();
+ QualType FunctionType = Function->getType();
+
+ // Substitute any explicit template arguments.
+ llvm::SmallVector<TemplateArgument, 4> Deduced;
+ llvm::SmallVector<QualType, 4> ParamTypes;
+ if (ExplicitTemplateArgs) {
+ if (TemplateDeductionResult Result
+ = SubstituteExplicitTemplateArguments(FunctionTemplate,
+ *ExplicitTemplateArgs,
+ Deduced, ParamTypes,
+ &FunctionType, Info))
+ return Result;
+ }
+
+ // Template argument deduction for function templates in a SFINAE context.
+ // Trap any errors that might occur.
+ SFINAETrap Trap(*this);
+
+ Deduced.resize(TemplateParams->size());
+
+ if (!ArgFunctionType.isNull()) {
+ // Deduce template arguments from the function type.
+ if (TemplateDeductionResult Result
+ = ::DeduceTemplateArguments(*this, TemplateParams,
+ FunctionType, ArgFunctionType, Info,
+ Deduced, 0))
+ return Result;
+ }
+
+ return FinishTemplateArgumentDeduction(FunctionTemplate, Deduced,
+ Specialization, Info);
+}
+
+/// \brief Deduce template arguments for a templated conversion
+/// function (C++ [temp.deduct.conv]) and, if successful, produce a
+/// conversion function template specialization.
+Sema::TemplateDeductionResult
+Sema::DeduceTemplateArguments(FunctionTemplateDecl *FunctionTemplate,
+ QualType ToType,
+ CXXConversionDecl *&Specialization,
+ TemplateDeductionInfo &Info) {
+ CXXConversionDecl *Conv
+ = cast<CXXConversionDecl>(FunctionTemplate->getTemplatedDecl());
+ QualType FromType = Conv->getConversionType();
+
+ // Canonicalize the types for deduction.
+ QualType P = Context.getCanonicalType(FromType);
+ QualType A = Context.getCanonicalType(ToType);
+
+ // C++0x [temp.deduct.conv]p3:
+ // If P is a reference type, the type referred to by P is used for
+ // type deduction.
+ if (const ReferenceType *PRef = P->getAs<ReferenceType>())
+ P = PRef->getPointeeType();
+
+ // C++0x [temp.deduct.conv]p3:
+ // If A is a reference type, the type referred to by A is used
+ // for type deduction.
+ if (const ReferenceType *ARef = A->getAs<ReferenceType>())
+ A = ARef->getPointeeType();
+ // C++ [temp.deduct.conv]p2:
+ //
+ // If A is not a reference type:
+ else {
+ assert(!A->isReferenceType() && "Reference types were handled above");
+
+ // - If P is an array type, the pointer type produced by the
+ // array-to-pointer standard conversion (4.2) is used in place
+ // of P for type deduction; otherwise,
+ if (P->isArrayType())
+ P = Context.getArrayDecayedType(P);
+ // - If P is a function type, the pointer type produced by the
+ // function-to-pointer standard conversion (4.3) is used in
+ // place of P for type deduction; otherwise,
+ else if (P->isFunctionType())
+ P = Context.getPointerType(P);
+ // - If P is a cv-qualified type, the top level cv-qualifiers of
+ // P’s type are ignored for type deduction.
+ else
+ P = P.getUnqualifiedType();
+
+ // C++0x [temp.deduct.conv]p3:
+ // If A is a cv-qualified type, the top level cv-qualifiers of A’s
+ // type are ignored for type deduction.
+ A = A.getUnqualifiedType();
+ }
+
+ // Template argument deduction for function templates in a SFINAE context.
+ // Trap any errors that might occur.
+ SFINAETrap Trap(*this);
+
+ // C++ [temp.deduct.conv]p1:
+ // Template argument deduction is done by comparing the return
+ // type of the template conversion function (call it P) with the
+ // type that is required as the result of the conversion (call it
+ // A) as described in 14.8.2.4.
+ TemplateParameterList *TemplateParams
+ = FunctionTemplate->getTemplateParameters();
+ llvm::SmallVector<TemplateArgument, 4> Deduced;
+ Deduced.resize(TemplateParams->size());
+
+ // C++0x [temp.deduct.conv]p4:
+ // In general, the deduction process attempts to find template
+ // argument values that will make the deduced A identical to
+ // A. However, there are two cases that allow a difference:
+ unsigned TDF = 0;
+ // - If the original A is a reference type, A can be more
+ // cv-qualified than the deduced A (i.e., the type referred to
+ // by the reference)
+ if (ToType->isReferenceType())
+ TDF |= TDF_ParamWithReferenceType;
+ // - The deduced A can be another pointer or pointer to member
+ // type that can be converted to A via a qualification
+ // conversion.
+ //
+ // (C++0x [temp.deduct.conv]p6 clarifies that this only happens when
+ // both P and A are pointers or member pointers. In this case, we
+ // just ignore cv-qualifiers completely).
+ if ((P->isPointerType() && A->isPointerType()) ||
+ (P->isMemberPointerType() && P->isMemberPointerType()))
+ TDF |= TDF_IgnoreQualifiers;
+ if (TemplateDeductionResult Result
+ = ::DeduceTemplateArguments(*this, TemplateParams,
+ P, A, Info, Deduced, TDF))
+ return Result;
+
+ // FIXME: we need to check that the deduced A is the same as A,
+ // modulo the various allowed differences.
+
+ // Finish template argument deduction.
+ FunctionDecl *Spec = 0;
+ TemplateDeductionResult Result
+ = FinishTemplateArgumentDeduction(FunctionTemplate, Deduced, Spec, Info);
+ Specialization = cast_or_null<CXXConversionDecl>(Spec);
+ return Result;
+}
+
+/// \brief Deduce template arguments for a function template when there is
+/// nothing to deduce against (C++0x [temp.arg.explicit]p3).
+///
+/// \param FunctionTemplate the function template for which we are performing
+/// template argument deduction.
+///
+/// \param ExplicitTemplateArguments the explicitly-specified template
+/// arguments.
+///
+/// \param Specialization if template argument deduction was successful,
+/// this will be set to the function template specialization produced by
+/// template argument deduction.
+///
+/// \param Info the argument will be updated to provide additional information
+/// about template argument deduction.
+///
+/// \returns the result of template argument deduction.
+Sema::TemplateDeductionResult
+Sema::DeduceTemplateArguments(FunctionTemplateDecl *FunctionTemplate,
+ const TemplateArgumentListInfo *ExplicitTemplateArgs,
+ FunctionDecl *&Specialization,
+ TemplateDeductionInfo &Info) {
+ return DeduceTemplateArguments(FunctionTemplate, ExplicitTemplateArgs,
+ QualType(), Specialization, Info);
+}
+
+/// \brief Stores the result of comparing the qualifiers of two types.
+enum DeductionQualifierComparison {
+ NeitherMoreQualified = 0,
+ ParamMoreQualified,
+ ArgMoreQualified
+};
+
+/// \brief Deduce the template arguments during partial ordering by comparing
+/// the parameter type and the argument type (C++0x [temp.deduct.partial]).
+///
+/// \param S the semantic analysis object within which we are deducing
+///
+/// \param TemplateParams the template parameters that we are deducing
+///
+/// \param ParamIn the parameter type
+///
+/// \param ArgIn the argument type
+///
+/// \param Info information about the template argument deduction itself
+///
+/// \param Deduced the deduced template arguments
+///
+/// \returns the result of template argument deduction so far. Note that a
+/// "success" result means that template argument deduction has not yet failed,
+/// but it may still fail, later, for other reasons.
+static Sema::TemplateDeductionResult
+DeduceTemplateArgumentsDuringPartialOrdering(Sema &S,
+ TemplateParameterList *TemplateParams,
+ QualType ParamIn, QualType ArgIn,
+ Sema::TemplateDeductionInfo &Info,
+ llvm::SmallVectorImpl<TemplateArgument> &Deduced,
+ llvm::SmallVectorImpl<DeductionQualifierComparison> *QualifierComparisons) {
+ CanQualType Param = S.Context.getCanonicalType(ParamIn);
+ CanQualType Arg = S.Context.getCanonicalType(ArgIn);
+
+ // C++0x [temp.deduct.partial]p5:
+ // Before the partial ordering is done, certain transformations are
+ // performed on the types used for partial ordering:
+ // - If P is a reference type, P is replaced by the type referred to.
+ CanQual<ReferenceType> ParamRef = Param->getAs<ReferenceType>();
+ if (!ParamRef.isNull())
+ Param = ParamRef->getPointeeType();
+
+ // - If A is a reference type, A is replaced by the type referred to.
+ CanQual<ReferenceType> ArgRef = Arg->getAs<ReferenceType>();
+ if (!ArgRef.isNull())
+ Arg = ArgRef->getPointeeType();
+
+ if (QualifierComparisons && !ParamRef.isNull() && !ArgRef.isNull()) {
+ // C++0x [temp.deduct.partial]p6:
+ // If both P and A were reference types (before being replaced with the
+ // type referred to above), determine which of the two types (if any) is
+ // more cv-qualified than the other; otherwise the types are considered to
+ // be equally cv-qualified for partial ordering purposes. The result of this
+ // determination will be used below.
+ //
+ // We save this information for later, using it only when deduction
+ // succeeds in both directions.
+ DeductionQualifierComparison QualifierResult = NeitherMoreQualified;
+ if (Param.isMoreQualifiedThan(Arg))
+ QualifierResult = ParamMoreQualified;
+ else if (Arg.isMoreQualifiedThan(Param))
+ QualifierResult = ArgMoreQualified;
+ QualifierComparisons->push_back(QualifierResult);
+ }
+
+ // C++0x [temp.deduct.partial]p7:
+ // Remove any top-level cv-qualifiers:
+ // - If P is a cv-qualified type, P is replaced by the cv-unqualified
+ // version of P.
+ Param = Param.getUnqualifiedType();
+ // - If A is a cv-qualified type, A is replaced by the cv-unqualified
+ // version of A.
+ Arg = Arg.getUnqualifiedType();
+
+ // C++0x [temp.deduct.partial]p8:
+ // Using the resulting types P and A the deduction is then done as
+ // described in 14.9.2.5. If deduction succeeds for a given type, the type
+ // from the argument template is considered to be at least as specialized
+ // as the type from the parameter template.
+ return DeduceTemplateArguments(S, TemplateParams, Param, Arg, Info,
+ Deduced, TDF_None);
+}
+
+static void
+MarkUsedTemplateParameters(Sema &SemaRef, QualType T,
+ bool OnlyDeduced,
+ unsigned Level,
+ llvm::SmallVectorImpl<bool> &Deduced);
+
+/// \brief Determine whether the function template \p FT1 is at least as
+/// specialized as \p FT2.
+static bool isAtLeastAsSpecializedAs(Sema &S,
+ SourceLocation Loc,
+ FunctionTemplateDecl *FT1,
+ FunctionTemplateDecl *FT2,
+ TemplatePartialOrderingContext TPOC,
+ llvm::SmallVectorImpl<DeductionQualifierComparison> *QualifierComparisons) {
+ FunctionDecl *FD1 = FT1->getTemplatedDecl();
+ FunctionDecl *FD2 = FT2->getTemplatedDecl();
+ const FunctionProtoType *Proto1 = FD1->getType()->getAs<FunctionProtoType>();
+ const FunctionProtoType *Proto2 = FD2->getType()->getAs<FunctionProtoType>();
+
+ assert(Proto1 && Proto2 && "Function templates must have prototypes");
+ TemplateParameterList *TemplateParams = FT2->getTemplateParameters();
+ llvm::SmallVector<TemplateArgument, 4> Deduced;
+ Deduced.resize(TemplateParams->size());
+
+ // C++0x [temp.deduct.partial]p3:
+ // The types used to determine the ordering depend on the context in which
+ // the partial ordering is done:
+ Sema::TemplateDeductionInfo Info(S.Context, Loc);
+ switch (TPOC) {
+ case TPOC_Call: {
+ // - In the context of a function call, the function parameter types are
+ // used.
+ unsigned NumParams = std::min(Proto1->getNumArgs(), Proto2->getNumArgs());
+ for (unsigned I = 0; I != NumParams; ++I)
+ if (DeduceTemplateArgumentsDuringPartialOrdering(S,
+ TemplateParams,
+ Proto2->getArgType(I),
+ Proto1->getArgType(I),
+ Info,
+ Deduced,
+ QualifierComparisons))
+ return false;
+
+ break;
+ }
+
+ case TPOC_Conversion:
+ // - In the context of a call to a conversion operator, the return types
+ // of the conversion function templates are used.
+ if (DeduceTemplateArgumentsDuringPartialOrdering(S,
+ TemplateParams,
+ Proto2->getResultType(),
+ Proto1->getResultType(),
+ Info,
+ Deduced,
+ QualifierComparisons))
+ return false;
+ break;
+
+ case TPOC_Other:
+ // - In other contexts (14.6.6.2) the function template’s function type
+ // is used.
+ if (DeduceTemplateArgumentsDuringPartialOrdering(S,
+ TemplateParams,
+ FD2->getType(),
+ FD1->getType(),
+ Info,
+ Deduced,
+ QualifierComparisons))
+ return false;
+ break;
+ }
+
+ // C++0x [temp.deduct.partial]p11:
+ // In most cases, all template parameters must have values in order for
+ // deduction to succeed, but for partial ordering purposes a template
+ // parameter may remain without a value provided it is not used in the
+ // types being used for partial ordering. [ Note: a template parameter used
+ // in a non-deduced context is considered used. -end note]
+ unsigned ArgIdx = 0, NumArgs = Deduced.size();
+ for (; ArgIdx != NumArgs; ++ArgIdx)
+ if (Deduced[ArgIdx].isNull())
+ break;
+
+ if (ArgIdx == NumArgs) {
+ // All template arguments were deduced. FT1 is at least as specialized
+ // as FT2.
+ return true;
+ }
+
+ // Figure out which template parameters were used.
+ llvm::SmallVector<bool, 4> UsedParameters;
+ UsedParameters.resize(TemplateParams->size());
+ switch (TPOC) {
+ case TPOC_Call: {
+ unsigned NumParams = std::min(Proto1->getNumArgs(), Proto2->getNumArgs());
+ for (unsigned I = 0; I != NumParams; ++I)
+ ::MarkUsedTemplateParameters(S, Proto2->getArgType(I), false,
+ TemplateParams->getDepth(),
+ UsedParameters);
+ break;
+ }
+
+ case TPOC_Conversion:
+ ::MarkUsedTemplateParameters(S, Proto2->getResultType(), false,
+ TemplateParams->getDepth(),
+ UsedParameters);
+ break;
+
+ case TPOC_Other:
+ ::MarkUsedTemplateParameters(S, FD2->getType(), false,
+ TemplateParams->getDepth(),
+ UsedParameters);
+ break;
+ }
+
+ for (; ArgIdx != NumArgs; ++ArgIdx)
+ // If this argument had no value deduced but was used in one of the types
+ // used for partial ordering, then deduction fails.
+ if (Deduced[ArgIdx].isNull() && UsedParameters[ArgIdx])
+ return false;
+
+ return true;
+}
+
+
+/// \brief Returns the more specialized function template according
+/// to the rules of function template partial ordering (C++ [temp.func.order]).
+///
+/// \param FT1 the first function template
+///
+/// \param FT2 the second function template
+///
+/// \param TPOC the context in which we are performing partial ordering of
+/// function templates.
+///
+/// \returns the more specialized function template. If neither
+/// template is more specialized, returns NULL.
+FunctionTemplateDecl *
+Sema::getMoreSpecializedTemplate(FunctionTemplateDecl *FT1,
+ FunctionTemplateDecl *FT2,
+ SourceLocation Loc,
+ TemplatePartialOrderingContext TPOC) {
+ llvm::SmallVector<DeductionQualifierComparison, 4> QualifierComparisons;
+ bool Better1 = isAtLeastAsSpecializedAs(*this, Loc, FT1, FT2, TPOC, 0);
+ bool Better2 = isAtLeastAsSpecializedAs(*this, Loc, FT2, FT1, TPOC,
+ &QualifierComparisons);
+
+ if (Better1 != Better2) // We have a clear winner
+ return Better1? FT1 : FT2;
+
+ if (!Better1 && !Better2) // Neither is better than the other
+ return 0;
+
+
+ // C++0x [temp.deduct.partial]p10:
+ // If for each type being considered a given template is at least as
+ // specialized for all types and more specialized for some set of types and
+ // the other template is not more specialized for any types or is not at
+ // least as specialized for any types, then the given template is more
+ // specialized than the other template. Otherwise, neither template is more
+ // specialized than the other.
+ Better1 = false;
+ Better2 = false;
+ for (unsigned I = 0, N = QualifierComparisons.size(); I != N; ++I) {
+ // C++0x [temp.deduct.partial]p9:
+ // If, for a given type, deduction succeeds in both directions (i.e., the
+ // types are identical after the transformations above) and if the type
+ // from the argument template is more cv-qualified than the type from the
+ // parameter template (as described above) that type is considered to be
+ // more specialized than the other. If neither type is more cv-qualified
+ // than the other then neither type is more specialized than the other.
+ switch (QualifierComparisons[I]) {
+ case NeitherMoreQualified:
+ break;
+
+ case ParamMoreQualified:
+ Better1 = true;
+ if (Better2)
+ return 0;
+ break;
+
+ case ArgMoreQualified:
+ Better2 = true;
+ if (Better1)
+ return 0;
+ break;
+ }
+ }
+
+ assert(!(Better1 && Better2) && "Should have broken out in the loop above");
+ if (Better1)
+ return FT1;
+ else if (Better2)
+ return FT2;
+ else
+ return 0;
+}
+
+/// \brief Determine if the two templates are equivalent.
+static bool isSameTemplate(TemplateDecl *T1, TemplateDecl *T2) {
+ if (T1 == T2)
+ return true;
+
+ if (!T1 || !T2)
+ return false;
+
+ return T1->getCanonicalDecl() == T2->getCanonicalDecl();
+}
+
+/// \brief Retrieve the most specialized of the given function template
+/// specializations.
+///
+/// \param SpecBegin the start iterator of the function template
+/// specializations that we will be comparing.
+///
+/// \param SpecEnd the end iterator of the function template
+/// specializations, paired with \p SpecBegin.
+///
+/// \param TPOC the partial ordering context to use to compare the function
+/// template specializations.
+///
+/// \param Loc the location where the ambiguity or no-specializations
+/// diagnostic should occur.
+///
+/// \param NoneDiag partial diagnostic used to diagnose cases where there are
+/// no matching candidates.
+///
+/// \param AmbigDiag partial diagnostic used to diagnose an ambiguity, if one
+/// occurs.
+///
+/// \param CandidateDiag partial diagnostic used for each function template
+/// specialization that is a candidate in the ambiguous ordering. One parameter
+/// in this diagnostic should be unbound, which will correspond to the string
+/// describing the template arguments for the function template specialization.
+///
+/// \param Index if non-NULL and the result of this function is non-nULL,
+/// receives the index corresponding to the resulting function template
+/// specialization.
+///
+/// \returns the most specialized function template specialization, if
+/// found. Otherwise, returns SpecEnd.
+///
+/// \todo FIXME: Consider passing in the "also-ran" candidates that failed
+/// template argument deduction.
+UnresolvedSetIterator
+Sema::getMostSpecialized(UnresolvedSetIterator SpecBegin,
+ UnresolvedSetIterator SpecEnd,
+ TemplatePartialOrderingContext TPOC,
+ SourceLocation Loc,
+ const PartialDiagnostic &NoneDiag,
+ const PartialDiagnostic &AmbigDiag,
+ const PartialDiagnostic &CandidateDiag) {
+ if (SpecBegin == SpecEnd) {
+ Diag(Loc, NoneDiag);
+ return SpecEnd;
+ }
+
+ if (SpecBegin + 1 == SpecEnd)
+ return SpecBegin;
+
+ // Find the function template that is better than all of the templates it
+ // has been compared to.
+ UnresolvedSetIterator Best = SpecBegin;
+ FunctionTemplateDecl *BestTemplate
+ = cast<FunctionDecl>(*Best)->getPrimaryTemplate();
+ assert(BestTemplate && "Not a function template specialization?");
+ for (UnresolvedSetIterator I = SpecBegin + 1; I != SpecEnd; ++I) {
+ FunctionTemplateDecl *Challenger
+ = cast<FunctionDecl>(*I)->getPrimaryTemplate();
+ assert(Challenger && "Not a function template specialization?");
+ if (isSameTemplate(getMoreSpecializedTemplate(BestTemplate, Challenger,
+ Loc, TPOC),
+ Challenger)) {
+ Best = I;
+ BestTemplate = Challenger;
+ }
+ }
+
+ // Make sure that the "best" function template is more specialized than all
+ // of the others.
+ bool Ambiguous = false;
+ for (UnresolvedSetIterator I = SpecBegin; I != SpecEnd; ++I) {
+ FunctionTemplateDecl *Challenger
+ = cast<FunctionDecl>(*I)->getPrimaryTemplate();
+ if (I != Best &&
+ !isSameTemplate(getMoreSpecializedTemplate(BestTemplate, Challenger,
+ Loc, TPOC),
+ BestTemplate)) {
+ Ambiguous = true;
+ break;
+ }
+ }
+
+ if (!Ambiguous) {
+ // We found an answer. Return it.
+ return Best;
+ }
+
+ // Diagnose the ambiguity.
+ Diag(Loc, AmbigDiag);
+
+ // FIXME: Can we order the candidates in some sane way?
+ for (UnresolvedSetIterator I = SpecBegin; I != SpecEnd; ++I)
+ Diag((*I)->getLocation(), CandidateDiag)
+ << getTemplateArgumentBindingsText(
+ cast<FunctionDecl>(*I)->getPrimaryTemplate()->getTemplateParameters(),
+ *cast<FunctionDecl>(*I)->getTemplateSpecializationArgs());
+
+ return SpecEnd;
+}
+
+/// \brief Returns the more specialized class template partial specialization
+/// according to the rules of partial ordering of class template partial
+/// specializations (C++ [temp.class.order]).
+///
+/// \param PS1 the first class template partial specialization
+///
+/// \param PS2 the second class template partial specialization
+///
+/// \returns the more specialized class template partial specialization. If
+/// neither partial specialization is more specialized, returns NULL.
+ClassTemplatePartialSpecializationDecl *
+Sema::getMoreSpecializedPartialSpecialization(
+ ClassTemplatePartialSpecializationDecl *PS1,
+ ClassTemplatePartialSpecializationDecl *PS2,
+ SourceLocation Loc) {
+ // C++ [temp.class.order]p1:
+ // For two class template partial specializations, the first is at least as
+ // specialized as the second if, given the following rewrite to two
+ // function templates, the first function template is at least as
+ // specialized as the second according to the ordering rules for function
+ // templates (14.6.6.2):
+ // - the first function template has the same template parameters as the
+ // first partial specialization and has a single function parameter
+ // whose type is a class template specialization with the template
+ // arguments of the first partial specialization, and
+ // - the second function template has the same template parameters as the
+ // second partial specialization and has a single function parameter
+ // whose type is a class template specialization with the template
+ // arguments of the second partial specialization.
+ //
+ // Rather than synthesize function templates, we merely perform the
+ // equivalent partial ordering by performing deduction directly on the
+ // template arguments of the class template partial specializations. This
+ // computation is slightly simpler than the general problem of function
+ // template partial ordering, because class template partial specializations
+ // are more constrained. We know that every template parameter is deduc
+ llvm::SmallVector<TemplateArgument, 4> Deduced;
+ Sema::TemplateDeductionInfo Info(Context, Loc);
+
+ // Determine whether PS1 is at least as specialized as PS2
+ Deduced.resize(PS2->getTemplateParameters()->size());
+ bool Better1 = !DeduceTemplateArgumentsDuringPartialOrdering(*this,
+ PS2->getTemplateParameters(),
+ Context.getTypeDeclType(PS2),
+ Context.getTypeDeclType(PS1),
+ Info,
+ Deduced,
+ 0);
+
+ // Determine whether PS2 is at least as specialized as PS1
+ Deduced.clear();
+ Deduced.resize(PS1->getTemplateParameters()->size());
+ bool Better2 = !DeduceTemplateArgumentsDuringPartialOrdering(*this,
+ PS1->getTemplateParameters(),
+ Context.getTypeDeclType(PS1),
+ Context.getTypeDeclType(PS2),
+ Info,
+ Deduced,
+ 0);
+
+ if (Better1 == Better2)
+ return 0;
+
+ return Better1? PS1 : PS2;
+}
+
+static void
+MarkUsedTemplateParameters(Sema &SemaRef,
+ const TemplateArgument &TemplateArg,
+ bool OnlyDeduced,
+ unsigned Depth,
+ llvm::SmallVectorImpl<bool> &Used);
+
+/// \brief Mark the template parameters that are used by the given
+/// expression.
+static void
+MarkUsedTemplateParameters(Sema &SemaRef,
+ const Expr *E,
+ bool OnlyDeduced,
+ unsigned Depth,
+ llvm::SmallVectorImpl<bool> &Used) {
+ // FIXME: if !OnlyDeduced, we have to walk the whole subexpression to
+ // find other occurrences of template parameters.
+ const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E);
+ if (!DRE)
+ return;
+
+ const NonTypeTemplateParmDecl *NTTP
+ = dyn_cast<NonTypeTemplateParmDecl>(DRE->getDecl());
+ if (!NTTP)
+ return;
+
+ if (NTTP->getDepth() == Depth)
+ Used[NTTP->getIndex()] = true;
+}
+
+/// \brief Mark the template parameters that are used by the given
+/// nested name specifier.
+static void
+MarkUsedTemplateParameters(Sema &SemaRef,
+ NestedNameSpecifier *NNS,
+ bool OnlyDeduced,
+ unsigned Depth,
+ llvm::SmallVectorImpl<bool> &Used) {
+ if (!NNS)
+ return;
+
+ MarkUsedTemplateParameters(SemaRef, NNS->getPrefix(), OnlyDeduced, Depth,
+ Used);
+ MarkUsedTemplateParameters(SemaRef, QualType(NNS->getAsType(), 0),
+ OnlyDeduced, Depth, Used);
+}
+
+/// \brief Mark the template parameters that are used by the given
+/// template name.
+static void
+MarkUsedTemplateParameters(Sema &SemaRef,
+ TemplateName Name,
+ bool OnlyDeduced,
+ unsigned Depth,
+ llvm::SmallVectorImpl<bool> &Used) {
+ if (TemplateDecl *Template = Name.getAsTemplateDecl()) {
+ if (TemplateTemplateParmDecl *TTP
+ = dyn_cast<TemplateTemplateParmDecl>(Template)) {
+ if (TTP->getDepth() == Depth)
+ Used[TTP->getIndex()] = true;
+ }
+ return;
+ }
+
+ if (QualifiedTemplateName *QTN = Name.getAsQualifiedTemplateName())
+ MarkUsedTemplateParameters(SemaRef, QTN->getQualifier(), OnlyDeduced,
+ Depth, Used);
+ if (DependentTemplateName *DTN = Name.getAsDependentTemplateName())
+ MarkUsedTemplateParameters(SemaRef, DTN->getQualifier(), OnlyDeduced,
+ Depth, Used);
+}
+
+/// \brief Mark the template parameters that are used by the given
+/// type.
+static void
+MarkUsedTemplateParameters(Sema &SemaRef, QualType T,
+ bool OnlyDeduced,
+ unsigned Depth,
+ llvm::SmallVectorImpl<bool> &Used) {
+ if (T.isNull())
+ return;
+
+ // Non-dependent types have nothing deducible
+ if (!T->isDependentType())
+ return;
+
+ T = SemaRef.Context.getCanonicalType(T);
+ switch (T->getTypeClass()) {
+ case Type::Pointer:
+ MarkUsedTemplateParameters(SemaRef,
+ cast<PointerType>(T)->getPointeeType(),
+ OnlyDeduced,
+ Depth,
+ Used);
+ break;
+
+ case Type::BlockPointer:
+ MarkUsedTemplateParameters(SemaRef,
+ cast<BlockPointerType>(T)->getPointeeType(),
+ OnlyDeduced,
+ Depth,
+ Used);
+ break;
+
+ case Type::LValueReference:
+ case Type::RValueReference:
+ MarkUsedTemplateParameters(SemaRef,
+ cast<ReferenceType>(T)->getPointeeType(),
+ OnlyDeduced,
+ Depth,
+ Used);
+ break;
+
+ case Type::MemberPointer: {
+ const MemberPointerType *MemPtr = cast<MemberPointerType>(T.getTypePtr());
+ MarkUsedTemplateParameters(SemaRef, MemPtr->getPointeeType(), OnlyDeduced,
+ Depth, Used);
+ MarkUsedTemplateParameters(SemaRef, QualType(MemPtr->getClass(), 0),
+ OnlyDeduced, Depth, Used);
+ break;
+ }
+
+ case Type::DependentSizedArray:
+ MarkUsedTemplateParameters(SemaRef,
+ cast<DependentSizedArrayType>(T)->getSizeExpr(),
+ OnlyDeduced, Depth, Used);
+ // Fall through to check the element type
+
+ case Type::ConstantArray:
+ case Type::IncompleteArray:
+ MarkUsedTemplateParameters(SemaRef,
+ cast<ArrayType>(T)->getElementType(),
+ OnlyDeduced, Depth, Used);
+ break;
+
+ case Type::Vector:
+ case Type::ExtVector:
+ MarkUsedTemplateParameters(SemaRef,
+ cast<VectorType>(T)->getElementType(),
+ OnlyDeduced, Depth, Used);
+ break;
+
+ case Type::DependentSizedExtVector: {
+ const DependentSizedExtVectorType *VecType
+ = cast<DependentSizedExtVectorType>(T);
+ MarkUsedTemplateParameters(SemaRef, VecType->getElementType(), OnlyDeduced,
+ Depth, Used);
+ MarkUsedTemplateParameters(SemaRef, VecType->getSizeExpr(), OnlyDeduced,
+ Depth, Used);
+ break;
+ }
+
+ case Type::FunctionProto: {
+ const FunctionProtoType *Proto = cast<FunctionProtoType>(T);
+ MarkUsedTemplateParameters(SemaRef, Proto->getResultType(), OnlyDeduced,
+ Depth, Used);
+ for (unsigned I = 0, N = Proto->getNumArgs(); I != N; ++I)
+ MarkUsedTemplateParameters(SemaRef, Proto->getArgType(I), OnlyDeduced,
+ Depth, Used);
+ break;
+ }
+
+ case Type::TemplateTypeParm: {
+ const TemplateTypeParmType *TTP = cast<TemplateTypeParmType>(T);
+ if (TTP->getDepth() == Depth)
+ Used[TTP->getIndex()] = true;
+ break;
+ }
+
+ case Type::TemplateSpecialization: {
+ const TemplateSpecializationType *Spec
+ = cast<TemplateSpecializationType>(T);
+ MarkUsedTemplateParameters(SemaRef, Spec->getTemplateName(), OnlyDeduced,
+ Depth, Used);
+ for (unsigned I = 0, N = Spec->getNumArgs(); I != N; ++I)
+ MarkUsedTemplateParameters(SemaRef, Spec->getArg(I), OnlyDeduced, Depth,
+ Used);
+ break;
+ }
+
+ case Type::Complex:
+ if (!OnlyDeduced)
+ MarkUsedTemplateParameters(SemaRef,
+ cast<ComplexType>(T)->getElementType(),
+ OnlyDeduced, Depth, Used);
+ break;
+
+ case Type::Typename:
+ if (!OnlyDeduced)
+ MarkUsedTemplateParameters(SemaRef,
+ cast<TypenameType>(T)->getQualifier(),
+ OnlyDeduced, Depth, Used);
+ break;
+
+ // None of these types have any template parameters in them.
+ case Type::Builtin:
+ case Type::VariableArray:
+ case Type::FunctionNoProto:
+ case Type::Record:
+ case Type::Enum:
+ case Type::ObjCInterface:
+ case Type::ObjCObjectPointer:
+ case Type::UnresolvedUsing:
+#define TYPE(Class, Base)
+#define ABSTRACT_TYPE(Class, Base)
+#define DEPENDENT_TYPE(Class, Base)
+#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
+#include "clang/AST/TypeNodes.def"
+ break;
+ }
+}
+
+/// \brief Mark the template parameters that are used by this
+/// template argument.
+static void
+MarkUsedTemplateParameters(Sema &SemaRef,
+ const TemplateArgument &TemplateArg,
+ bool OnlyDeduced,
+ unsigned Depth,
+ llvm::SmallVectorImpl<bool> &Used) {
+ switch (TemplateArg.getKind()) {
+ case TemplateArgument::Null:
+ case TemplateArgument::Integral:
+ case TemplateArgument::Declaration:
+ break;
+
+ case TemplateArgument::Type:
+ MarkUsedTemplateParameters(SemaRef, TemplateArg.getAsType(), OnlyDeduced,
+ Depth, Used);
+ break;
+
+ case TemplateArgument::Template:
+ MarkUsedTemplateParameters(SemaRef, TemplateArg.getAsTemplate(),
+ OnlyDeduced, Depth, Used);
+ break;
+
+ case TemplateArgument::Expression:
+ MarkUsedTemplateParameters(SemaRef, TemplateArg.getAsExpr(), OnlyDeduced,
+ Depth, Used);
+ break;
+
+ case TemplateArgument::Pack:
+ for (TemplateArgument::pack_iterator P = TemplateArg.pack_begin(),
+ PEnd = TemplateArg.pack_end();
+ P != PEnd; ++P)
+ MarkUsedTemplateParameters(SemaRef, *P, OnlyDeduced, Depth, Used);
+ break;
+ }
+}
+
+/// \brief Mark the template parameters can be deduced by the given
+/// template argument list.
+///
+/// \param TemplateArgs the template argument list from which template
+/// parameters will be deduced.
+///
+/// \param Deduced a bit vector whose elements will be set to \c true
+/// to indicate when the corresponding template parameter will be
+/// deduced.
+void
+Sema::MarkUsedTemplateParameters(const TemplateArgumentList &TemplateArgs,
+ bool OnlyDeduced, unsigned Depth,
+ llvm::SmallVectorImpl<bool> &Used) {
+ for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I)
+ ::MarkUsedTemplateParameters(*this, TemplateArgs[I], OnlyDeduced,
+ Depth, Used);
+}
+
+/// \brief Marks all of the template parameters that will be deduced by a
+/// call to the given function template.
+void Sema::MarkDeducedTemplateParameters(FunctionTemplateDecl *FunctionTemplate,
+ llvm::SmallVectorImpl<bool> &Deduced) {
+ TemplateParameterList *TemplateParams
+ = FunctionTemplate->getTemplateParameters();
+ Deduced.clear();
+ Deduced.resize(TemplateParams->size());
+
+ FunctionDecl *Function = FunctionTemplate->getTemplatedDecl();
+ for (unsigned I = 0, N = Function->getNumParams(); I != N; ++I)
+ ::MarkUsedTemplateParameters(*this, Function->getParamDecl(I)->getType(),
+ true, TemplateParams->getDepth(), Deduced);
+}