C++ TemplateArgument类代码示例

bool TemplateArgument::structurallyEquals(const TemplateArgument &Other) const {
  if (getKind() != Other.getKind()) return false;

  switch (getKind()) {
  case Null:
  case Type:
  case Declaration:
  case Template:
  case Expression:
    return TypeOrValue == Other.TypeOrValue;

  case Integral:
    return getIntegralType() == Other.getIntegralType() &&
           *getAsIntegral() == *Other.getAsIntegral();

  case Pack:
    if (Args.NumArgs != Other.Args.NumArgs) return false;
    for (unsigned I = 0, E = Args.NumArgs; I != E; ++I)
      if (!Args.Args[I].structurallyEquals(Other.Args.Args[I]))
        return false;
    return true;
  }

  // Suppress warnings.
  return false;
}

void ReduceClassTemplateParameter::removeOneParameterByArgExpression(
       const ClassTemplatePartialSpecializationDecl *PartialD,
       const TemplateArgument &Arg)
{
  TransAssert((Arg.getKind() == TemplateArgument::Expression) && 
              "Arg is not TemplateArgument::Expression!");

  const Expr *E = Arg.getAsExpr();
  TransAssert(E && "Bad Expression!");
  const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E->IgnoreParenCasts());
  TransAssert(DRE && "Bad DeclRefExpr!");
  const NonTypeTemplateParmDecl *ParmD = 
    dyn_cast<NonTypeTemplateParmDecl>(DRE->getDecl());
  TransAssert(ParmD && "Invalid NonTypeTemplateParmDecl!");
  
  const TemplateParameterList *TPList = PartialD->getTemplateParameters();
  unsigned Idx = 0;
  for (TemplateParameterList::const_iterator I = TPList->begin(),
       E = TPList->end(); I != E; ++I) {
    if ((*I) == ParmD)
      break;
    Idx++;
  }

  unsigned NumParams = TPList->size();
  TransAssert((Idx < NumParams) && "Cannot find valid TemplateParameter!");
  (void)NumParams;
  SourceRange Range = ParmD->getSourceRange();
  removeParameterByRange(Range, TPList, Idx);
}

void ODRHash::AddTemplateArgument(TemplateArgument TA) {
  const auto Kind = TA.getKind();
  ID.AddInteger(Kind);
  switch (Kind) {
  case TemplateArgument::Null:
    llvm_unreachable("Require valid TemplateArgument");
  case TemplateArgument::Type:
    AddQualType(TA.getAsType());
    break;
  case TemplateArgument::Declaration:
    AddDecl(TA.getAsDecl());
    break;
  case TemplateArgument::NullPtr:
    AddQualType(TA.getNullPtrType());
    break;
  case TemplateArgument::Integral:
    TA.getAsIntegral().Profile(ID);
    AddQualType(TA.getIntegralType());
    break;
  case TemplateArgument::Template:
  case TemplateArgument::TemplateExpansion:
    AddTemplateName(TA.getAsTemplateOrTemplatePattern());
    break;
  case TemplateArgument::Expression:
    AddStmt(TA.getAsExpr());
    break;
  case TemplateArgument::Pack:
    ID.AddInteger(TA.pack_size());
    for (auto SubTA : TA.pack_elements())
      AddTemplateArgument(SubTA);
    break;
  }
}

/// \brief Print a template integral argument value.
///
/// \param TemplArg the TemplateArgument instance to print.
///
/// \param Out the raw_ostream instance to use for printing.
///
/// \param Policy the printing policy for EnumConstantDecl printing.
static void printIntegral(const TemplateArgument &TemplArg,
                          raw_ostream &Out, const PrintingPolicy& Policy) {
  const ::clang::Type *T = TemplArg.getIntegralType().getTypePtr();
  const llvm::APSInt &Val = TemplArg.getAsIntegral();

  if (const EnumType *ET = T->getAs<EnumType>()) {
    for (const EnumConstantDecl* ECD : ET->getDecl()->enumerators()) {
      // In Sema::CheckTemplateArugment, enum template arguments value are
      // extended to the size of the integer underlying the enum type.  This
      // may create a size difference between the enum value and template
      // argument value, requiring isSameValue here instead of operator==.
      if (llvm::APSInt::isSameValue(ECD->getInitVal(), Val)) {
        ECD->printQualifiedName(Out, Policy);
        return;
      }
    }
  }

  if (T->isBooleanType() && !Policy.MSVCFormatting) {
    Out << (Val.getBoolValue() ? "true" : "false");
  } else if (T->isCharType()) {
    const char Ch = Val.getZExtValue();
    Out << ((Ch == '\'') ? "'\\" : "'");
    Out.write_escaped(StringRef(&Ch, 1), /*UseHexEscapes=*/ true);
    Out << "'";
  } else {
    Out << Val;
  }
}

bool TemplateArgument::structurallyEquals(const TemplateArgument &Other) const {
  if (getKind() != Other.getKind()) return false;

  switch (getKind()) {
  case Null:
  case Type:
  case Expression:      
  case Template:
  case TemplateExpansion:
  case NullPtr:
    return TypeOrValue.V == Other.TypeOrValue.V;

  case Declaration:
    return getAsDecl() == Other.getAsDecl() && 
           isDeclForReferenceParam() && Other.isDeclForReferenceParam();

  case Integral:
    return getIntegralType() == Other.getIntegralType() &&
           getAsIntegral() == Other.getAsIntegral();

  case Pack:
    if (Args.NumArgs != Other.Args.NumArgs) return false;
    for (unsigned I = 0, E = Args.NumArgs; I != E; ++I)
      if (!Args.Args[I].structurallyEquals(Other.Args.Args[I]))
        return false;
    return true;
  }

  llvm_unreachable("Invalid TemplateArgument Kind!");
}

bool TemplateNonTypeArgToInt::isValidTemplateArgument(
       const TemplateArgument &Arg)
{
  TemplateArgument::ArgKind K = Arg.getKind();
  switch (K) {
  case TemplateArgument::Declaration: {
    return true;
  }

  case TemplateArgument::Expression: {
    const Expr *E = Arg.getAsExpr()->IgnoreParenCasts();
    if (dyn_cast<IntegerLiteral>(E) || dyn_cast<CXXBoolLiteralExpr>(E))
      return false;
    if (const UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
      UnaryOperator::Opcode Op = UO->getOpcode();
      if((Op == UO_Minus) || (Op == UO_Plus))
        return false;
    }

    return true;
  }

  default:
    TransAssert(0 && "Unreachable code!");
    return false;
  }
  TransAssert(0 && "Unreachable code!");
  return false;
}

void ReduceClassTemplateParameter::removeOneParameterFromPartialDecl(
       const ClassTemplatePartialSpecializationDecl *PartialD,
       const TemplateArgument &Arg)
{
  if (!Arg.isInstantiationDependent())
    return;

  TemplateArgument::ArgKind K = Arg.getKind();
  switch (K) {
  case TemplateArgument::Expression:
    removeOneParameterByArgExpression(PartialD, Arg);
    return;

  case TemplateArgument::Template:
    removeOneParameterByArgTemplate(PartialD, Arg);
    return;

  case TemplateArgument::Type:
    removeOneParameterByArgType(PartialD, Arg);
    return;
  
  default:
    TransAssert(0 && "Uncatched ArgKind!");
  }
  TransAssert(0 && "Unreachable code!");
}

void StmtProfiler::VisitTemplateArgument(const TemplateArgument &Arg) {
    // Mostly repetitive with TemplateArgument::Profile!
    ID.AddInteger(Arg.getKind());
    switch (Arg.getKind()) {
        case TemplateArgument::Null:
            break;

        case TemplateArgument::Type:
            VisitType(Arg.getAsType());
            break;

        case TemplateArgument::Template:
            VisitTemplateName(Arg.getAsTemplate());
            break;

        case TemplateArgument::Declaration:
            VisitDecl(Arg.getAsDecl());
            break;

        case TemplateArgument::Integral:
            Arg.getAsIntegral()->Profile(ID);
            VisitType(Arg.getIntegralType());
            break;

        case TemplateArgument::Expression:
            Visit(Arg.getAsExpr());
            break;

        case TemplateArgument::Pack:
            const TemplateArgument *Pack = Arg.pack_begin();
            for (unsigned i = 0, e = Arg.pack_size(); i != e; ++i)
                VisitTemplateArgument(Pack[i]);
            break;
    }
}

SubstNonTypeTemplateParmPackExpr::
SubstNonTypeTemplateParmPackExpr(QualType T, 
                                 NonTypeTemplateParmDecl *Param,
                                 SourceLocation NameLoc,
                                 const TemplateArgument &ArgPack)
  : Expr(SubstNonTypeTemplateParmPackExprClass, T, VK_RValue, OK_Ordinary, 
         true, true, true, true),
    Param(Param), Arguments(ArgPack.pack_begin()), 
    NumArguments(ArgPack.pack_size()), NameLoc(NameLoc) { }

static void describeTemplateParameter(raw_ostream &Out,
                                      const TemplateArgument &TArg,
                                      const LangOptions &LO) {

  if (TArg.getKind() == TemplateArgument::ArgKind::Pack) {
    describeTemplateParameters(Out, TArg.getPackAsArray(), LO);
  } else {
    TArg.print(PrintingPolicy(LO), Out);
  }
}

Type *
TypeCheck::visit(TemplateArgumentList *ast)
{
	FUNCLOG;
	List<TemplateArgument*>::iterator it = ast->args.begin();
	while (it != ast->args.end()) {
		TemplateArgument *arg = *it;
		arg->accept(this);
		++it;
	}
	return NULL;
}

bool 
InstantiateTemplateParam::getTemplateArgumentString(const TemplateArgument &Arg,
                                                    std::string &ArgStr, 
                                                    std::string &ForwardStr)
{
  ArgStr = "";
  ForwardStr = "";
  if (Arg.getKind() != TemplateArgument::Type)
    return false;
  QualType QT = Arg.getAsType();
  return getTypeString(QT, ArgStr, ForwardStr);
}

CXType clang_Cursor_getTemplateArgumentType(CXCursor C, unsigned I) {
  TemplateArgument TA;
  if (clang_Cursor_getTemplateArgument(C, I, &TA) !=
      CXGetTemplateArgumentStatus_Success) {
    return cxtype::MakeCXType(QualType(), getCursorTU(C));
  }

  if (TA.getKind() != TemplateArgument::Type) {
    return cxtype::MakeCXType(QualType(), getCursorTU(C));
  }

  return cxtype::MakeCXType(TA.getAsType(), getCursorTU(C));
}

Optional<unsigned> Sema::getFullyPackExpandedSize(TemplateArgument Arg) {
  assert(Arg.containsUnexpandedParameterPack());

  // If this is a substituted pack, grab that pack. If not, we don't know
  // the size yet.
  // FIXME: We could find a size in more cases by looking for a substituted
  // pack anywhere within this argument, but that's not necessary in the common
  // case for 'sizeof...(A)' handling.
  TemplateArgument Pack;
  switch (Arg.getKind()) {
  case TemplateArgument::Type:
    if (auto *Subst = Arg.getAsType()->getAs<SubstTemplateTypeParmPackType>())
      Pack = Subst->getArgumentPack();
    else
      return None;
    break;

  case TemplateArgument::Expression:
    if (auto *Subst =
            dyn_cast<SubstNonTypeTemplateParmPackExpr>(Arg.getAsExpr()))
      Pack = Subst->getArgumentPack();
    else if (auto *Subst = dyn_cast<FunctionParmPackExpr>(Arg.getAsExpr()))  {
      for (ParmVarDecl *PD : *Subst)
        if (PD->isParameterPack())
          return None;
      return Subst->getNumExpansions();
    } else
      return None;
    break;

  case TemplateArgument::Template:
    if (SubstTemplateTemplateParmPackStorage *Subst =
            Arg.getAsTemplate().getAsSubstTemplateTemplateParmPack())
      Pack = Subst->getArgumentPack();
    else
      return None;
    break;

  case TemplateArgument::Declaration:
  case TemplateArgument::NullPtr:
  case TemplateArgument::TemplateExpansion:
  case TemplateArgument::Integral:
  case TemplateArgument::Pack:
  case TemplateArgument::Null:
    return None;
  }

  // Check that no argument in the pack is itself a pack expansion.
  for (TemplateArgument Elem : Pack.pack_elements()) {
    // There's no point recursing in this case; we would have already
    // expanded this pack expansion into the enclosing pack if we could.
    if (Elem.isPackExpansion())
      return None;
  }
  return Pack.pack_size();
}

long long clang_Cursor_getTemplateArgumentValue(CXCursor C, unsigned I) {
  TemplateArgument TA;
  if (clang_Cursor_getTemplateArgument(C, I, &TA) !=
      CXGetTemplateArgumentStatus_Success) {
    assert(0 && "Unable to retrieve TemplateArgument");
    return 0;
  }

  if (TA.getKind() != TemplateArgument::Integral) {
    assert(0 && "Passed template argument is not Integral");
    return 0;
  }

  return TA.getAsIntegral().getSExtValue();
}