C++ ObjCMethodCall::isReceiverSelfOrSuper方法代码示例

static Nullability getReceiverNullability(const ObjCMethodCall &M,
                                          ProgramStateRef State) {
  if (M.isReceiverSelfOrSuper()) {
    // For super and super class receivers we assume that the receiver is
    // nonnull.
    return Nullability::Nonnull;
  }
  // Otherwise look up nullability in the state.
  SVal Receiver = M.getReceiverSVal();
  if (auto DefOrUnknown = Receiver.getAs<DefinedOrUnknownSVal>()) {
    // If the receiver is constrained to be nonnull, assume that it is nonnull
    // regardless of its type.
    NullConstraint Nullness = getNullConstraint(*DefOrUnknown, State);
    if (Nullness == NullConstraint::IsNotNull)
      return Nullability::Nonnull;
  }
  auto ValueRegionSVal = Receiver.getAs<loc::MemRegionVal>();
  if (ValueRegionSVal) {
    const MemRegion *SelfRegion = ValueRegionSVal->getRegion();
    assert(SelfRegion);

    const NullabilityState *TrackedSelfNullability =
        State->get<NullabilityMap>(SelfRegion);
    if (TrackedSelfNullability)
      return TrackedSelfNullability->getValue();
  }
  return Nullability::Unspecified;
}

/// If we are in -dealloc or -dealloc is on the stack, handle the call if it is
/// a release or a nilling-out property setter.
void ObjCDeallocChecker::checkPreObjCMessage(
    const ObjCMethodCall &M, CheckerContext &C) const {
  // Only run if -dealloc is on the stack.
  SVal DeallocedInstance;
  if (!instanceDeallocIsOnStack(C, DeallocedInstance))
    return;

  SymbolRef ReleasedValue = nullptr;

  if (M.getSelector() == ReleaseSel) {
    ReleasedValue = M.getReceiverSVal().getAsSymbol();
  } else if (M.getSelector() == DeallocSel && !M.isReceiverSelfOrSuper()) {
    if (diagnoseMistakenDealloc(M.getReceiverSVal().getAsSymbol(), M, C))
      return;
  }

  if (ReleasedValue) {
    // An instance variable symbol was released with -release:
    //    [_property release];
    if (diagnoseExtraRelease(ReleasedValue,M, C))
      return;
  } else {
    // An instance variable symbol was released nilling out its property:
    //    self.property = nil;
    ReleasedValue = getValueReleasedByNillingOut(M, C);
  }

  if (!ReleasedValue)
    return;

  transitionToReleaseValue(C, ReleasedValue);
}

void ObjCNonNilReturnValueChecker::checkPostObjCMessage(const ObjCMethodCall &M,
                                                        CheckerContext &C)
                                                        const {
  ProgramStateRef State = C.getState();

  if (!Initialized) {
    ASTContext &Ctx = C.getASTContext();
    ObjectAtIndex = GetUnarySelector("objectAtIndex", Ctx);
    ObjectAtIndexedSubscript = GetUnarySelector("objectAtIndexedSubscript", Ctx);
    NullSelector = GetNullarySelector("null", Ctx);
  }

  // Check the receiver type.
  if (const ObjCInterfaceDecl *Interface = M.getReceiverInterface()) {

    // Assume that object returned from '[self init]' or '[super init]' is not
    // 'nil' if we are processing an inlined function/method.
    //
    // A defensive callee will (and should) check if the object returned by
    // '[super init]' is 'nil' before doing it's own initialization. However,
    // since 'nil' is rarely returned in practice, we should not warn when the
    // caller to the defensive constructor uses the object in contexts where
    // 'nil' is not accepted.
    if (!C.inTopFrame() && M.getDecl() &&
        M.getDecl()->getMethodFamily() == OMF_init &&
        M.isReceiverSelfOrSuper()) {
      State = assumeExprIsNonNull(M.getOriginExpr(), State, C);
    }

    FoundationClass Cl = findKnownClass(Interface);

    // Objects returned from
    // [NSArray|NSOrderedSet]::[ObjectAtIndex|ObjectAtIndexedSubscript]
    // are never 'nil'.
    if (Cl == FC_NSArray || Cl == FC_NSOrderedSet) {
      Selector Sel = M.getSelector();
      if (Sel == ObjectAtIndex || Sel == ObjectAtIndexedSubscript) {
        // Go ahead and assume the value is non-nil.
        State = assumeExprIsNonNull(M.getOriginExpr(), State, C);
      }
    }

    // Objects returned from [NSNull null] are not nil.
    if (Cl == FC_NSNull) {
      if (M.getSelector() == NullSelector) {
        // Go ahead and assume the value is non-nil.
        State = assumeExprIsNonNull(M.getOriginExpr(), State, C);
      }
    }
  }
  C.addTransition(State);
}