C++ QualType::isFunctionType方法代码示例

/// CheckAllocatedType - Checks that a type is suitable as the allocated type
/// in a new-expression.
/// dimension off and stores the size expression in ArraySize.
bool Sema::CheckAllocatedType(QualType AllocType, const Declarator &D)
{
  // C++ 5.3.4p1: "[The] type shall be a complete object type, but not an
  //   abstract class type or array thereof.
  if (AllocType->isFunctionType())
    return Diag(D.getSourceRange().getBegin(), diag::err_bad_new_type)
      << AllocType << 0 << D.getSourceRange();
  else if (AllocType->isReferenceType())
    return Diag(D.getSourceRange().getBegin(), diag::err_bad_new_type)
      << AllocType << 1 << D.getSourceRange();
  else if (!AllocType->isDependentType() &&
           RequireCompleteType(D.getSourceRange().getBegin(), AllocType,
                               diag::err_new_incomplete_type,
                               D.getSourceRange()))
    return true;
  else if (RequireNonAbstractType(D.getSourceRange().getBegin(), AllocType,
                                  diag::err_allocation_of_abstract_type))
    return true;

  // Every dimension shall be of constant size.
  unsigned i = 1;
  while (const ArrayType *Array = Context.getAsArrayType(AllocType)) {
    if (!Array->isConstantArrayType()) {
      Diag(D.getTypeObject(i).Loc, diag::err_new_array_nonconst)
        << static_cast<Expr*>(D.getTypeObject(i).Arr.NumElts)->getSourceRange();
      return true;
    }
    AllocType = Array->getElementType();
    ++i;
  }

  return false;
}

long long clang_Type_getSizeOf(CXType T) {
  if (T.kind == CXType_Invalid)
    return CXTypeLayoutError_Invalid;
  ASTContext &Ctx = cxtu::getASTUnit(GetTU(T))->getASTContext();
  QualType QT = GetQualType(T);
  // [expr.sizeof] p2: if reference type, return size of referenced type
  if (QT->isReferenceType())
    QT = QT.getNonReferenceType();
  // [expr.sizeof] p1: return -1 on: func, incomplete, bitfield, incomplete
  //                   enumeration
  // Note: We get the cxtype, not the cxcursor, so we can't call
  //       FieldDecl->isBitField()
  // [expr.sizeof] p3: pointer ok, function not ok.
  // [gcc extension] lib/AST/ExprConstant.cpp:1372 HandleSizeof : vla == error
  if (QT->isIncompleteType())
    return CXTypeLayoutError_Incomplete;
  if (QT->isDependentType())
    return CXTypeLayoutError_Dependent;
  if (!QT->isConstantSizeType())
    return CXTypeLayoutError_NotConstantSize;
  // [gcc extension] lib/AST/ExprConstant.cpp:1372
  //                 HandleSizeof : {voidtype,functype} == 1
  // not handled by ASTContext.cpp:1313 getTypeInfoImpl
  if (QT->isVoidType() || QT->isFunctionType())
    return 1;
  return Ctx.getTypeSizeInChars(QT).getQuantity();
}

ExprResult Sema::LookupInlineAsmIdentifier(CXXScopeSpec &SS,
                                           SourceLocation TemplateKWLoc,
                                           UnqualifiedId &Id,
                                           llvm::InlineAsmIdentifierInfo &Info,
                                           bool IsUnevaluatedContext) {
  Info.clear();

  if (IsUnevaluatedContext)
    PushExpressionEvaluationContext(UnevaluatedAbstract,
                                    ReuseLambdaContextDecl);

  ExprResult Result = ActOnIdExpression(getCurScope(), SS, TemplateKWLoc, Id,
                                        /*trailing lparen*/ false,
                                        /*is & operand*/ false,
                                        /*CorrectionCandidateCallback=*/nullptr,
                                        /*IsInlineAsmIdentifier=*/ true);

  if (IsUnevaluatedContext)
    PopExpressionEvaluationContext();

  if (!Result.isUsable()) return Result;

  Result = CheckPlaceholderExpr(Result.get());
  if (!Result.isUsable()) return Result;

  QualType T = Result.get()->getType();

  // For now, reject dependent types.
  if (T->isDependentType()) {
    Diag(Id.getLocStart(), diag::err_asm_incomplete_type) << T;
    return ExprError();
  }

  // Any sort of function type is fine.
  if (T->isFunctionType()) {
    return Result;
  }

  // Otherwise, it needs to be a complete type.
  if (RequireCompleteExprType(Result.get(), diag::err_asm_incomplete_type)) {
    return ExprError();
  }

  // Compute the type size (and array length if applicable?).
  Info.Type = Info.Size = Context.getTypeSizeInChars(T).getQuantity();
  if (T->isArrayType()) {
    const ArrayType *ATy = Context.getAsArrayType(T);
    Info.Type = Context.getTypeSizeInChars(ATy->getElementType()).getQuantity();
    Info.Length = Info.Size / Info.Type;
  }

  // We can work with the expression as long as it's not an r-value.
  if (!Result.get()->isRValue())
    Info.IsVarDecl = true;

  return Result;
}

ExprResult Sema::LookupInlineAsmIdentifier(CXXScopeSpec &SS,
                                           SourceLocation TemplateKWLoc,
                                           UnqualifiedId &Id,
                                           llvm::InlineAsmIdentifierInfo &Info,
                                           bool IsUnevaluatedContext) {
  Info.clear();

  if (IsUnevaluatedContext)
    PushExpressionEvaluationContext(UnevaluatedAbstract,
                                    ReuseLambdaContextDecl);

  ExprResult Result = ActOnIdExpression(getCurScope(), SS, TemplateKWLoc, Id,
                                        /*trailing lparen*/ false,
                                        /*is & operand*/ false,
                                        /*CorrectionCandidateCallback=*/nullptr,
                                        /*IsInlineAsmIdentifier=*/ true);

  if (IsUnevaluatedContext)
    PopExpressionEvaluationContext();

  if (!Result.isUsable()) return Result;

  Result = CheckPlaceholderExpr(Result.get());
  if (!Result.isUsable()) return Result;

  // Referring to parameters is not allowed in naked functions.
  if (CheckNakedParmReference(Result.get(), *this))
    return ExprError();

  QualType T = Result.get()->getType();

  // For now, reject dependent types.
  if (T->isDependentType()) {
    Diag(Id.getLocStart(), diag::err_asm_incomplete_type) << T;
    return ExprError();
  }

  // Any sort of function type is fine.
  if (T->isFunctionType()) {
    return Result;
  }

  // Otherwise, it needs to be a complete type.
  if (RequireCompleteExprType(Result.get(), diag::err_asm_incomplete_type)) {
    return ExprError();
  }

  fillInlineAsmTypeInfo(Context, T, Info);

  // We can work with the expression as long as it's not an r-value.
  if (!Result.get()->isRValue())
    Info.IsVarDecl = true;

  return Result;
}

/// ActOnCXXConditionDeclarationExpr - Parsed a condition declaration of a
/// C++ if/switch/while/for statement.
/// e.g: "if (int x = f()) {...}"
Action::OwningExprResult
Sema::ActOnCXXConditionDeclarationExpr(Scope *S, SourceLocation StartLoc,
                                       Declarator &D,
                                       SourceLocation EqualLoc,
                                       ExprArg AssignExprVal) {
  assert(AssignExprVal.get() && "Null assignment expression");

  // C++ 6.4p2:
  // The declarator shall not specify a function or an array.
  // The type-specifier-seq shall not contain typedef and shall not declare a
  // new class or enumeration.

  assert(D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef &&
         "Parser allowed 'typedef' as storage class of condition decl.");

  QualType Ty = GetTypeForDeclarator(D, S);
  
  if (Ty->isFunctionType()) { // The declarator shall not specify a function...
    // We exit without creating a CXXConditionDeclExpr because a FunctionDecl
    // would be created and CXXConditionDeclExpr wants a VarDecl.
    return ExprError(Diag(StartLoc, diag::err_invalid_use_of_function_type)
      << SourceRange(StartLoc, EqualLoc));
  } else if (Ty->isArrayType()) { // ...or an array.
    Diag(StartLoc, diag::err_invalid_use_of_array_type)
      << SourceRange(StartLoc, EqualLoc);
  } else if (const RecordType *RT = Ty->getAsRecordType()) {
    RecordDecl *RD = RT->getDecl();
    // The type-specifier-seq shall not declare a new class...
    if (RD->isDefinition() &&
        (RD->getIdentifier() == 0 || S->isDeclScope(DeclPtrTy::make(RD))))
      Diag(RD->getLocation(), diag::err_type_defined_in_condition);
  } else if (const EnumType *ET = Ty->getAsEnumType()) {
    EnumDecl *ED = ET->getDecl();
    // ...or enumeration.
    if (ED->isDefinition() &&
        (ED->getIdentifier() == 0 || S->isDeclScope(DeclPtrTy::make(ED))))
      Diag(ED->getLocation(), diag::err_type_defined_in_condition);
  }

  DeclPtrTy Dcl = ActOnDeclarator(S, D, DeclPtrTy());
  if (!Dcl)
    return ExprError();
  AddInitializerToDecl(Dcl, move(AssignExprVal));

  // Mark this variable as one that is declared within a conditional.
  // We know that the decl had to be a VarDecl because that is the only type of
  // decl that can be assigned and the grammar requires an '='.
  VarDecl *VD = cast<VarDecl>(Dcl.getAs<Decl>());
  VD->setDeclaredInCondition(true);
  return Owned(new (Context) CXXConditionDeclExpr(StartLoc, EqualLoc, VD));
}

// <type> ::= <pointer-type>
// <pointer-type> ::= <pointer-cvr-qualifiers> <cvr-qualifiers> <type>
void MicrosoftCXXNameMangler::mangleType(const PointerType *T) {
  QualType PointeeTy = T->getPointeeType();
  if (PointeeTy->isArrayType()) {
    // Pointers to arrays are mangled like arrays.
    mangleExtraDimensions(T->getPointeeType());
  } else if (PointeeTy->isFunctionType()) {
    // Function pointers are special.
    Out << '6';
    mangleType(static_cast<const FunctionType *>(PointeeTy.getTypePtr()),
               NULL, false, false);
  } else {
    if (!PointeeTy.hasQualifiers())
      // Lack of qualifiers is mangled as 'A'.
      Out << 'A';
    mangleType(PointeeTy);
  }
}

  // We need to artificially create:
  // cling_PrintValue(void* (ASTContext)C, void* (Expr)E, const void* (&i)
  Expr* ValuePrinterSynthesizer::SynthesizeVP(Expr* E) {
    QualType QT = E->getType();
    // For now we skip void and function pointer types.
    if (!QT.isNull() && (QT->isVoidType() || QT->isFunctionType()))
      return 0;

    // Find cling_PrintValue
    SourceLocation NoSLoc = SourceLocation();
    DeclarationName PVName = &m_Context->Idents.get("cling_PrintValue");
    LookupResult R(*m_Sema, PVName, NoSLoc, Sema::LookupOrdinaryName,
                   Sema::ForRedeclaration);

    Scope* S = m_Sema->getScopeForContext(m_Sema->CurContext);
    m_Sema->LookupName(R, S);
    assert(!R.empty() && "Cannot find cling_PrintValue(...)");

    CXXScopeSpec CSS;
    Expr* UnresolvedLookup
      = m_Sema->BuildDeclarationNameExpr(CSS, R, /*ADL*/ false).take();


    Expr* VoidEArg = utils::Synthesize::CStyleCastPtrExpr(m_Sema, 
                                                          m_Context->VoidPtrTy,
                                                          (uint64_t)E);
    Expr* VoidCArg = utils::Synthesize::CStyleCastPtrExpr(m_Sema, 
                                                          m_Context->VoidPtrTy,
                                                          (uint64_t)m_Context);

    if (!QT->isPointerType()) {
      while(ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(E))
        E = ICE->getSubExpr();
      E = m_Sema->BuildUnaryOp(S, NoSLoc, UO_AddrOf, E).take();
    }

    llvm::SmallVector<Expr*, 4> CallArgs;
    CallArgs.push_back(VoidEArg);
    CallArgs.push_back(VoidCArg);
    CallArgs.push_back(E);

    Expr* Result = m_Sema->ActOnCallExpr(S, UnresolvedLookup, NoSLoc,
                                         CallArgs, NoSLoc).take();
    assert(Result && "Cannot create value printer!");

    return Result;
  }

  // We need to artificially create:
  // cling_PrintValue(void* (ASTContext)C, void* (Expr)E, const void* (&i)
  Expr* ValuePrinterSynthesizer::SynthesizeVP(Expr* E) {
    QualType QT = E->getType();
    // For now we skip void and function pointer types.
    if (!QT.isNull() && (QT->isVoidType() || QT->isFunctionType()))
      return 0;

    // Find cling_PrintValue
    if (!m_LookupResult)
      FindAndCacheRuntimeLookupResult(E->getLocStart());


    Expr* VoidEArg = utils::Synthesize::CStyleCastPtrExpr(m_Sema,
                                                          m_Context->VoidPtrTy,
                                                          (uint64_t)E);
    Expr* VoidCArg = utils::Synthesize::CStyleCastPtrExpr(m_Sema,
                                                          m_Context->VoidPtrTy,
                                                          (uint64_t)m_Context);

    SourceLocation NoSLoc = SourceLocation();
    Scope* S = m_Sema->getScopeForContext(m_Sema->CurContext);
    if (!QT->isPointerType()) {
      while(ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(E))
        E = ICE->getSubExpr();
      E = m_Sema->BuildUnaryOp(S, NoSLoc, UO_AddrOf, E).get();
    }

    llvm::SmallVector<Expr*, 4> CallArgs;
    CallArgs.push_back(VoidEArg);
    CallArgs.push_back(VoidCArg);
    CallArgs.push_back(E);

    CXXScopeSpec CSS;
    Expr* unresolvedLookup
      = m_Sema->BuildDeclarationNameExpr(CSS, *m_LookupResult,
                                         /*ADL*/ false).get();

    Expr* Result = m_Sema->ActOnCallExpr(S, unresolvedLookup, E->getLocStart(),
                                         CallArgs, E->getLocEnd()).get();
    assert(Result && "Cannot create value printer!");

    return Result;
  }

bool Declarator::isDeclarationOfFunction() const {
  for (unsigned i = 0, i_end = DeclTypeInfo.size(); i < i_end; ++i) {
    switch (DeclTypeInfo[i].Kind) {
    case DeclaratorChunk::Function:
      return true;
    case DeclaratorChunk::Paren:
      continue;
    case DeclaratorChunk::Pointer:
    case DeclaratorChunk::Reference:
    case DeclaratorChunk::Array:
    case DeclaratorChunk::BlockPointer:
    case DeclaratorChunk::MemberPointer:
      return false;
    }
    llvm_unreachable("Invalid type chunk");
  }
  
  switch (DS.getTypeSpecType()) {
    case TST_atomic:
    case TST_auto:
    case TST_bool:
    case TST_char:
    case TST_char16:
    case TST_char32:
    case TST_class:
    case TST_decimal128:
    case TST_decimal32:
    case TST_decimal64:
    case TST_double:
    case TST_enum:
    case TST_error:
    case TST_float:
    case TST_half:
    case TST_int:
    case TST_int128:
    case TST_struct:
    case TST_interface:
    case TST_union:
    case TST_unknown_anytype:
    case TST_unspecified:
    case TST_void:
    case TST_wchar:
      return false;

    case TST_decltype_auto:
      // This must have an initializer, so can't be a function declaration,
      // even if the initializer has function type.
      return false;

    case TST_decltype:
    case TST_typeofExpr:
      if (Expr *E = DS.getRepAsExpr())
        return E->getType()->isFunctionType();
      return false;
     
    case TST_underlyingType:
    case TST_typename:
    case TST_typeofType: {
      QualType QT = DS.getRepAsType().get();
      if (QT.isNull())
        return false;
      
      if (const LocInfoType *LIT = dyn_cast<LocInfoType>(QT))
        QT = LIT->getType();

      if (QT.isNull())
        return false;
        
      return QT->isFunctionType();
    }
  }

  llvm_unreachable("Invalid TypeSpecType!");
}

//.........这里部分代码省略.........
  if (!castTy->isVariableArrayType() && !originalTy->isVariableArrayType())
    if (shouldBeModeledWithNoOp(Context, Context.getPointerType(castTy),
                                         Context.getPointerType(originalTy)))
      return val;
  
  // Check for casts from pointers to integers.
  if (castTy->isIntegralOrEnumerationType() && Loc::isLocType(originalTy))
    return evalCastFromLoc(val.castAs<Loc>(), castTy);

  // Check for casts from integers to pointers.
  if (Loc::isLocType(castTy) && originalTy->isIntegralOrEnumerationType()) {
    if (Optional<nonloc::LocAsInteger> LV = val.getAs<nonloc::LocAsInteger>()) {
      if (const MemRegion *R = LV->getLoc().getAsRegion()) {
        StoreManager &storeMgr = StateMgr.getStoreManager();
        R = storeMgr.castRegion(R, castTy);
        return R ? SVal(loc::MemRegionVal(R)) : UnknownVal();
      }
      return LV->getLoc();
    }
    return dispatchCast(val, castTy);
  }

  // Just pass through function and block pointers.
  if (originalTy->isBlockPointerType() || originalTy->isFunctionPointerType()) {
    assert(Loc::isLocType(castTy));
    return val;
  }

  // Check for casts from array type to another type.
  if (const ArrayType *arrayT =
                      dyn_cast<ArrayType>(originalTy.getCanonicalType())) {
    // We will always decay to a pointer.
    QualType elemTy = arrayT->getElementType();
    val = StateMgr.ArrayToPointer(val.castAs<Loc>(), elemTy);

    // Are we casting from an array to a pointer?  If so just pass on
    // the decayed value.
    if (castTy->isPointerType() || castTy->isReferenceType())
      return val;

    // Are we casting from an array to an integer?  If so, cast the decayed
    // pointer value to an integer.
    assert(castTy->isIntegralOrEnumerationType());

    // FIXME: Keep these here for now in case we decide soon that we
    // need the original decayed type.
    //    QualType elemTy = cast<ArrayType>(originalTy)->getElementType();
    //    QualType pointerTy = C.getPointerType(elemTy);
    return evalCastFromLoc(val.castAs<Loc>(), castTy);
  }

  // Check for casts from a region to a specific type.
  if (const MemRegion *R = val.getAsRegion()) {
    // Handle other casts of locations to integers.
    if (castTy->isIntegralOrEnumerationType())
      return evalCastFromLoc(loc::MemRegionVal(R), castTy);

    // FIXME: We should handle the case where we strip off view layers to get
    //  to a desugared type.
    if (!Loc::isLocType(castTy)) {
      // FIXME: There can be gross cases where one casts the result of a function
      // (that returns a pointer) to some other value that happens to fit
      // within that pointer value.  We currently have no good way to
      // model such operations.  When this happens, the underlying operation
      // is that the caller is reasoning about bits.  Conceptually we are
      // layering a "view" of a location on top of those bits.  Perhaps
      // we need to be more lazy about mutual possible views, even on an
      // SVal?  This may be necessary for bit-level reasoning as well.
      return UnknownVal();
    }

    // We get a symbolic function pointer for a dereference of a function
    // pointer, but it is of function type. Example:

    //  struct FPRec {
    //    void (*my_func)(int * x);
    //  };
    //
    //  int bar(int x);
    //
    //  int f1_a(struct FPRec* foo) {
    //    int x;
    //    (*foo->my_func)(&x);
    //    return bar(x)+1; // no-warning
    //  }

    assert(Loc::isLocType(originalTy) || originalTy->isFunctionType() ||
           originalTy->isBlockPointerType() || castTy->isReferenceType());

    StoreManager &storeMgr = StateMgr.getStoreManager();

    // Delegate to store manager to get the result of casting a region to a
    // different type.  If the MemRegion* returned is NULL, this expression
    // Evaluates to UnknownVal.
    R = storeMgr.castRegion(R, castTy);
    return R ? SVal(loc::MemRegionVal(R)) : UnknownVal();
  }

  return dispatchCast(val, castTy);
}

void TypePrinter::printAttributedAfter(const AttributedType *T,
                                       raw_ostream &OS) {
  // Prefer the macro forms of the GC and ownership qualifiers.
  if (T->getAttrKind() == AttributedType::attr_objc_gc ||
      T->getAttrKind() == AttributedType::attr_objc_ownership)
    return printAfter(T->getEquivalentType(), OS);

  // TODO: not all attributes are GCC-style attributes.
  OS << " __attribute__((";
  switch (T->getAttrKind()) {
  case AttributedType::attr_address_space:
    OS << "address_space(";
    OS << T->getEquivalentType().getAddressSpace();
    OS << ')';
    break;

  case AttributedType::attr_vector_size: {
    OS << "__vector_size__(";
    if (const VectorType *vector =T->getEquivalentType()->getAs<VectorType>()) {
      OS << vector->getNumElements();
      OS << " * sizeof(";
      print(vector->getElementType(), OS, StringRef());
      OS << ')';
    }
    OS << ')';
    break;
  }

  case AttributedType::attr_neon_vector_type:
  case AttributedType::attr_neon_polyvector_type: {
    if (T->getAttrKind() == AttributedType::attr_neon_vector_type)
      OS << "neon_vector_type(";
    else
      OS << "neon_polyvector_type(";
    const VectorType *vector = T->getEquivalentType()->getAs<VectorType>();
    OS << vector->getNumElements();
    OS << ')';
    break;
  }

  case AttributedType::attr_regparm: {
    OS << "regparm(";
    QualType t = T->getEquivalentType();
    while (!t->isFunctionType())
      t = t->getPointeeType();
    OS << t->getAs<FunctionType>()->getRegParmType();
    OS << ')';
    break;
  }

  case AttributedType::attr_objc_gc: {
    OS << "objc_gc(";

    QualType tmp = T->getEquivalentType();
    while (tmp.getObjCGCAttr() == Qualifiers::GCNone) {
      QualType next = tmp->getPointeeType();
      if (next == tmp) break;
      tmp = next;
    }

    if (tmp.isObjCGCWeak())
      OS << "weak";
    else
      OS << "strong";
    OS << ')';
    break;
  }

  case AttributedType::attr_objc_ownership:
    OS << "objc_ownership(";
    switch (T->getEquivalentType().getObjCLifetime()) {
    case Qualifiers::OCL_None: llvm_unreachable("no ownership!");
    case Qualifiers::OCL_ExplicitNone: OS << "none"; break;
    case Qualifiers::OCL_Strong: OS << "strong"; break;
    case Qualifiers::OCL_Weak: OS << "weak"; break;
    case Qualifiers::OCL_Autoreleasing: OS << "autoreleasing"; break;
    }
    OS << ')';
    break;

  case AttributedType::attr_noreturn: OS << "noreturn"; break;
  case AttributedType::attr_cdecl: OS << "cdecl"; break;
  case AttributedType::attr_fastcall: OS << "fastcall"; break;
  case AttributedType::attr_stdcall: OS << "stdcall"; break;
  case AttributedType::attr_thiscall: OS << "thiscall"; break;
  case AttributedType::attr_pascal: OS << "pascal"; break;
  case AttributedType::attr_pcs: {
    OS << "pcs(";
   QualType t = T->getEquivalentType();
   while (!t->isFunctionType())
     t = t->getPointeeType();
   OS << (t->getAs<FunctionType>()->getCallConv() == CC_AAPCS ?
         "\"aapcs\"" : "\"aapcs-vfp\"");
   OS << ')';
   break;
  }
  case AttributedType::attr_pnaclcall: OS << "pnaclcall"; break;
  case AttributedType::attr_inteloclbicc: OS << "inteloclbicc"; break;
  }
  OS << "))";
//.........这里部分代码省略.........

// FIXME: should rewrite according to the cast kind.
SVal SValBuilder::evalCast(SVal val, QualType castTy, QualType originalTy) {
  castTy = Context.getCanonicalType(castTy);
  originalTy = Context.getCanonicalType(originalTy);
  if (val.isUnknownOrUndef() || castTy == originalTy)
    return val;

  // For const casts, just propagate the value.
  if (!castTy->isVariableArrayType() && !originalTy->isVariableArrayType())
    if (haveSimilarTypes(Context, Context.getPointerType(castTy),
                                  Context.getPointerType(originalTy)))
      return val;
  
  // Check for casts from pointers to integers.
  if (castTy->isIntegerType() && Loc::isLocType(originalTy))
    return evalCastFromLoc(cast<Loc>(val), castTy);

  // Check for casts from integers to pointers.
  if (Loc::isLocType(castTy) && originalTy->isIntegerType()) {
    if (nonloc::LocAsInteger *LV = dyn_cast<nonloc::LocAsInteger>(&val)) {
      if (const MemRegion *R = LV->getLoc().getAsRegion()) {
        StoreManager &storeMgr = StateMgr.getStoreManager();
        R = storeMgr.castRegion(R, castTy);
        return R ? SVal(loc::MemRegionVal(R)) : UnknownVal();
      }
      return LV->getLoc();
    }
    return dispatchCast(val, castTy);
  }

  // Just pass through function and block pointers.
  if (originalTy->isBlockPointerType() || originalTy->isFunctionPointerType()) {
    assert(Loc::isLocType(castTy));
    return val;
  }

  // Check for casts from array type to another type.
  if (originalTy->isArrayType()) {
    // We will always decay to a pointer.
    val = StateMgr.ArrayToPointer(cast<Loc>(val));

    // Are we casting from an array to a pointer?  If so just pass on
    // the decayed value.
    if (castTy->isPointerType())
      return val;

    // Are we casting from an array to an integer?  If so, cast the decayed
    // pointer value to an integer.
    assert(castTy->isIntegerType());

    // FIXME: Keep these here for now in case we decide soon that we
    // need the original decayed type.
    //    QualType elemTy = cast<ArrayType>(originalTy)->getElementType();
    //    QualType pointerTy = C.getPointerType(elemTy);
    return evalCastFromLoc(cast<Loc>(val), castTy);
  }

  // Check for casts from a region to a specific type.
  if (const MemRegion *R = val.getAsRegion()) {
    // Handle other casts of locations to integers.
    if (castTy->isIntegerType())
      return evalCastFromLoc(loc::MemRegionVal(R), castTy);

    // FIXME: We should handle the case where we strip off view layers to get
    //  to a desugared type.
    if (!Loc::isLocType(castTy)) {
      // FIXME: There can be gross cases where one casts the result of a function
      // (that returns a pointer) to some other value that happens to fit
      // within that pointer value.  We currently have no good way to
      // model such operations.  When this happens, the underlying operation
      // is that the caller is reasoning about bits.  Conceptually we are
      // layering a "view" of a location on top of those bits.  Perhaps
      // we need to be more lazy about mutual possible views, even on an
      // SVal?  This may be necessary for bit-level reasoning as well.
      return UnknownVal();
    }

    // We get a symbolic function pointer for a dereference of a function
    // pointer, but it is of function type. Example:

    //  struct FPRec {
    //    void (*my_func)(int * x);
    //  };
    //
    //  int bar(int x);
    //
    //  int f1_a(struct FPRec* foo) {
    //    int x;
    //    (*foo->my_func)(&x);
    //    return bar(x)+1; // no-warning
    //  }

    assert(Loc::isLocType(originalTy) || originalTy->isFunctionType() ||
           originalTy->isBlockPointerType() || castTy->isReferenceType());

    StoreManager &storeMgr = StateMgr.getStoreManager();

    // Delegate to store manager to get the result of casting a region to a
    // different type.  If the MemRegion* returned is NULL, this expression
    // Evaluates to UnknownVal.
//.........这里部分代码省略.........

  void ValueExtractionSynthesizer::Transform() {
    const CompilationOptions& CO = getTransaction()->getCompilationOpts();
    // If we do not evaluate the result, or printing out the result return.
    if (!(CO.ResultEvaluation || CO.ValuePrinting))
      return;

    FunctionDecl* FD = getTransaction()->getWrapperFD();

    int foundAtPos = -1;
    Expr* lastExpr = utils::Analyze::GetOrCreateLastExpr(FD, &foundAtPos,
                                                         /*omitDS*/false,
                                                         m_Sema);
    if (foundAtPos < 0)
      return;

    typedef llvm::SmallVector<Stmt**, 4> StmtIters;
    StmtIters returnStmts;
    ReturnStmtCollector collector(returnStmts);
    CompoundStmt* CS = cast<CompoundStmt>(FD->getBody());
    collector.VisitStmt(CS);

    if (isa<Expr>(*(CS->body_begin() + foundAtPos)))
      returnStmts.push_back(CS->body_begin() + foundAtPos);

    // We want to support cases such as:
    // gCling->evaluate("if() return 'A' else return 12", V), that puts in V,
    // either A or 12.
    // In this case the void wrapper is compiled with the stmts returning
    // values. Sema would cast them to void, but the code will still be
    // executed. For example:
    // int g(); void f () { return g(); } will still call g().
    //
    for (StmtIters::iterator I = returnStmts.begin(), E = returnStmts.end();
         I != E; ++I) {
      ReturnStmt* RS = dyn_cast<ReturnStmt>(**I);
      if (RS) {
        // When we are handling a return stmt, the last expression must be the
        // return stmt value. Ignore the calculation of the lastStmt because it
        // might be wrong, in cases where the return is not in the end of the 
        // function.
        lastExpr = RS->getRetValue();
        if (lastExpr) {
          assert (lastExpr->getType()->isVoidType() && "Must be void type.");
          // Any return statement will have been "healed" by Sema
          // to correspond to the original void return type of the
          // wrapper, using a ImplicitCastExpr 'void' <ToVoid>.
          // Remove that.
          if (ImplicitCastExpr* VoidCast
              = dyn_cast<ImplicitCastExpr>(lastExpr)) {
            lastExpr = VoidCast->getSubExpr();
          }
        }
        // if no value assume void
        else {
          // We can't PushDeclContext, because we don't have scope.
          Sema::ContextRAII pushedDC(*m_Sema, FD);
          RS->setRetValue(SynthesizeSVRInit(0));
        }

      }
      else
        lastExpr = cast<Expr>(**I);

      if (lastExpr) {
        QualType lastExprTy = lastExpr->getType();
        // May happen on auto types which resolve to dependent.
        if (lastExprTy->isDependentType())
          continue;
        // Set up lastExpr properly.
        // Change the void function's return type
        // We can't PushDeclContext, because we don't have scope.
        Sema::ContextRAII pushedDC(*m_Sema, FD);

        if (lastExprTy->isFunctionType()) {
          // A return type of function needs to be converted to
          // pointer to function.
          lastExprTy = m_Context->getPointerType(lastExprTy);
          lastExpr = m_Sema->ImpCastExprToType(lastExpr, lastExprTy,
                                               CK_FunctionToPointerDecay,
                                               VK_RValue).take();
        }

        //
        // Here we don't want to depend on the JIT runFunction, because of its
        // limitations, when it comes to return value handling. There it is
        // not clear who provides the storage and who cleans it up in a
        // platform independent way.
        //
        // Depending on the type we need to synthesize a call to cling:
        // 0) void : set the value's type to void;
        // 1) enum, integral, float, double, referece, pointer types :
        //      call to cling::internal::setValueNoAlloc(...);
        // 2) object type (alloc on the stack) :
        //      cling::internal::setValueWithAlloc
        //   2.1) constant arrays:
        //          call to cling::runtime::internal::copyArray(...)
        //
        // We need to synthesize later:
        // Wrapper has signature: void w(cling::Value SVR)
        // case 1):
//.........这里部分代码省略.........

void TypePrinter::printAttributed(const AttributedType *T,
                                  std::string &S) {
  // Prefer the macro forms of the GC and ownership qualifiers.
  if (T->getAttrKind() == AttributedType::attr_objc_gc ||
      T->getAttrKind() == AttributedType::attr_objc_ownership)
    return print(T->getEquivalentType(), S);

  print(T->getModifiedType(), S);

  // TODO: not all attributes are GCC-style attributes.
  S += " __attribute__((";
  switch (T->getAttrKind()) {
  case AttributedType::attr_address_space:
    S += "address_space(";
    S += T->getEquivalentType().getAddressSpace();
    S += ")";
    break;

  case AttributedType::attr_vector_size: {
    S += "__vector_size__(";
    if (const VectorType *vector =T->getEquivalentType()->getAs<VectorType>()) {
      S += vector->getNumElements();
      S += " * sizeof(";

      std::string tmp;
      print(vector->getElementType(), tmp);
      S += tmp;
      S += ")";
    }
    S += ")";
    break;
  }

  case AttributedType::attr_neon_vector_type:
  case AttributedType::attr_neon_polyvector_type: {
    if (T->getAttrKind() == AttributedType::attr_neon_vector_type)
      S += "neon_vector_type(";
    else
      S += "neon_polyvector_type(";
    const VectorType *vector = T->getEquivalentType()->getAs<VectorType>();
    S += llvm::utostr_32(vector->getNumElements());
    S += ")";
    break;
  }

  case AttributedType::attr_regparm: {
    S += "regparm(";
    QualType t = T->getEquivalentType();
    while (!t->isFunctionType())
      t = t->getPointeeType();
    S += t->getAs<FunctionType>()->getRegParmType();
    S += ")";
    break;
  }

  case AttributedType::attr_objc_gc: {
    S += "objc_gc(";

    QualType tmp = T->getEquivalentType();
    while (tmp.getObjCGCAttr() == Qualifiers::GCNone) {
      QualType next = tmp->getPointeeType();
      if (next == tmp) break;
      tmp = next;
    }

    if (tmp.isObjCGCWeak())
      S += "weak";
    else
      S += "strong";
    S += ")";
    break;
  }

  case AttributedType::attr_objc_ownership:
    S += "objc_ownership(";
    switch (T->getEquivalentType().getObjCLifetime()) {
    case Qualifiers::OCL_None: llvm_unreachable("no ownership!"); break;
    case Qualifiers::OCL_ExplicitNone: S += "none"; break;
    case Qualifiers::OCL_Strong: S += "strong"; break;
    case Qualifiers::OCL_Weak: S += "weak"; break;
    case Qualifiers::OCL_Autoreleasing: S += "autoreleasing"; break;
    }
    S += ")";
    break;

  case AttributedType::attr_noreturn: S += "noreturn"; break;
  case AttributedType::attr_cdecl: S += "cdecl"; break;
  case AttributedType::attr_fastcall: S += "fastcall"; break;
  case AttributedType::attr_stdcall: S += "stdcall"; break;
  case AttributedType::attr_thiscall: S += "thiscall"; break;
  case AttributedType::attr_pascal: S += "pascal"; break;
  case AttributedType::attr_pcs: {
   S += "pcs(";
   QualType t = T->getEquivalentType();
   while (!t->isFunctionType())
     t = t->getPointeeType();
   S += (t->getAs<FunctionType>()->getCallConv() == CC_AAPCS ?
         "\"aapcs\"" : "\"aapcs-vfp\"");
   S += ")";
   break;
//.........这里部分代码省略.........

//.........这里部分代码省略.........
    return llvm::VectorType::get(ConvertTypeRecursive(VT.getElementType()),
                                 VT.getNumElements());
  }
  case Type::FunctionNoProto:
  case Type::FunctionProto: {
    // First, check whether we can build the full function type.
    if (const TagType* TT = VerifyFuncTypeComplete(&Ty)) {
      // This function's type depends on an incomplete tag type; make sure
      // we have an opaque type corresponding to the tag type.
      ConvertTagDeclType(TT->getDecl());
      // Create an opaque type for this function type, save it, and return it.
      llvm::Type *ResultType = llvm::OpaqueType::get(getLLVMContext());
      FunctionTypes.insert(std::make_pair(&Ty, ResultType));
      return ResultType;
    }
    // The function type can be built; call the appropriate routines to
    // build it.
    if (const FunctionProtoType *FPT = dyn_cast<FunctionProtoType>(&Ty))
      return GetFunctionType(getFunctionInfo(FPT), FPT->isVariadic());

    const FunctionNoProtoType *FNPT = cast<FunctionNoProtoType>(&Ty);
    return GetFunctionType(getFunctionInfo(FNPT), true);
  }

  case Type::ObjCInterface: {
    // Objective-C interfaces are always opaque (outside of the
    // runtime, which can do whatever it likes); we never refine
    // these.
    const llvm::Type *&T = InterfaceTypes[cast<ObjCInterfaceType>(&Ty)];
    if (!T)
        T = llvm::OpaqueType::get(getLLVMContext());
    return T;
  }

  case Type::ObjCObjectPointer: {
    // Protocol qualifications do not influence the LLVM type, we just return a
    // pointer to the underlying interface type. We don't need to worry about
    // recursive conversion.
    const llvm::Type *T =
      ConvertTypeRecursive(cast<ObjCObjectPointerType>(Ty).getPointeeType());
    return llvm::PointerType::getUnqual(T);
  }

  case Type::Record:
  case Type::Enum: {
    const TagDecl *TD = cast<TagType>(Ty).getDecl();
    const llvm::Type *Res = ConvertTagDeclType(TD);

    std::string TypeName(TD->getKindName());
    TypeName += '.';

    // Name the codegen type after the typedef name
    // if there is no tag type name available
    if (TD->getIdentifier())
      // FIXME: We should not have to check for a null decl context here.
      // Right now we do it because the implicit Obj-C decls don't have one.
      TypeName += TD->getDeclContext() ? TD->getQualifiedNameAsString() :
        TD->getNameAsString();
    else if (const TypedefType *TdT = dyn_cast<TypedefType>(T))
      // FIXME: We should not have to check for a null decl context here.
      // Right now we do it because the implicit Obj-C decls don't have one.
      TypeName += TdT->getDecl()->getDeclContext() ? 
        TdT->getDecl()->getQualifiedNameAsString() :
        TdT->getDecl()->getNameAsString();
    else
      TypeName += "anon";

    TheModule.addTypeName(TypeName, Res);
    return Res;
  }

  case Type::BlockPointer: {
    const QualType FTy = cast<BlockPointerType>(Ty).getPointeeType();
    llvm::OpaqueType *PointeeType = llvm::OpaqueType::get(getLLVMContext());
    PointersToResolve.push_back(std::make_pair(FTy, PointeeType));
    return llvm::PointerType::get(PointeeType, FTy.getAddressSpace());
  }

  case Type::MemberPointer: {
    // FIXME: This is ABI dependent. We use the Itanium C++ ABI.
    // http://www.codesourcery.com/public/cxx-abi/abi.html#member-pointers
    // If we ever want to support other ABIs this needs to be abstracted.

    QualType ETy = cast<MemberPointerType>(Ty).getPointeeType();
    const llvm::Type *PtrDiffTy =
        ConvertTypeRecursive(Context.getPointerDiffType());
    if (ETy->isFunctionType()) {
      return llvm::StructType::get(TheModule.getContext(), PtrDiffTy, PtrDiffTy,
                                   NULL);
    } else
      return PtrDiffTy;
  }

  case Type::TemplateSpecialization:
    assert(false && "Dependent types can't get here");
  }

  // FIXME: implement.
  return llvm::OpaqueType::get(getLLVMContext());
}