Beispiel #1
0
  @Override
  public boolean applyCondition(DfaValue dfaCond) {
    if (dfaCond instanceof DfaUnknownValue) return true;
    if (dfaCond instanceof DfaUnboxedValue) {
      DfaVariableValue dfaVar = ((DfaUnboxedValue) dfaCond).getVariable();
      boolean isNegated = dfaVar.isNegated();
      DfaVariableValue dfaNormalVar = isNegated ? dfaVar.createNegated() : dfaVar;
      final DfaValue boxedTrue =
          myFactory.getBoxedFactory().createBoxed(myFactory.getConstFactory().getTrue());
      return applyRelationCondition(
          myFactory
              .getRelationFactory()
              .createRelation(dfaNormalVar, boxedTrue, JavaTokenType.EQEQ, isNegated));
    }
    if (dfaCond instanceof DfaVariableValue) {
      DfaVariableValue dfaVar = (DfaVariableValue) dfaCond;
      boolean isNegated = dfaVar.isNegated();
      DfaVariableValue dfaNormalVar = isNegated ? dfaVar.createNegated() : dfaVar;
      DfaConstValue dfaTrue = myFactory.getConstFactory().getTrue();
      return applyRelationCondition(
          myFactory
              .getRelationFactory()
              .createRelation(dfaNormalVar, dfaTrue, JavaTokenType.EQEQ, isNegated));
    }

    if (dfaCond instanceof DfaConstValue) {
      return dfaCond == myFactory.getConstFactory().getTrue()
          || dfaCond != myFactory.getConstFactory().getFalse();
    }

    if (!(dfaCond instanceof DfaRelationValue)) return true;

    return applyRelationCondition((DfaRelationValue) dfaCond);
  }
Beispiel #2
0
 @Nullable
 private DfaRelationValue compareToNull(DfaValue dfaVar, boolean negated) {
   DfaConstValue dfaNull = myFactory.getConstFactory().getNull();
   return myFactory
       .getRelationFactory()
       .createRelation(dfaVar, dfaNull, JavaTokenType.EQEQ, negated);
 }
Beispiel #3
0
  @Override
  public boolean isNotNull(DfaValue dfaVar) {
    if (dfaVar instanceof DfaConstValue) return ((DfaConstValue) dfaVar).getValue() != null;
    if (dfaVar instanceof DfaBoxedValue) return true;
    if (dfaVar instanceof DfaTypeValue) return ((DfaTypeValue) dfaVar).isNotNull();
    if (dfaVar instanceof DfaVariableValue) {
      if (getVariableState((DfaVariableValue) dfaVar).isNotNull()) return true;

      DfaConstValue constantValue = getConstantValue((DfaVariableValue) dfaVar);
      if (constantValue != null && constantValue.getValue() != null) return true;
    }

    DfaConstValue dfaNull = myFactory.getConstFactory().getNull();
    int c1Index = getEqClassIndex(dfaVar);
    int c2Index = getEqClassIndex(dfaNull);
    if (c1Index < 0 || c2Index < 0) {
      return false;
    }

    long[] pairs = myDistinctClasses.toArray();
    for (long pair : pairs) {
      if (c1Index == low(pair) && c2Index == high(pair)
          || c1Index == high(pair) && c2Index == low(pair)) {
        return true;
      }
    }

    return false;
  }
 private DfaValue getDfaContractReturnValue(
     MethodContract contract, MethodCallInstruction instruction, DfaValueFactory factory) {
   switch (contract.returnValue) {
     case NULL_VALUE:
       return factory.getConstFactory().getNull();
     case NOT_NULL_VALUE:
       return factory.createTypeValue(instruction.getResultType(), Nullness.NOT_NULL);
     case TRUE_VALUE:
       return factory.getConstFactory().getTrue();
     case FALSE_VALUE:
       return factory.getConstFactory().getFalse();
     case THROW_EXCEPTION:
       return factory.getConstFactory().getContractFail();
     default:
       return getMethodResultValue(instruction, null, factory);
   }
 }
Beispiel #5
0
 private void updateVarStateOnComparison(@NotNull DfaVariableValue dfaVar, DfaValue value) {
   if (!isUnknownState(dfaVar)) {
     if (value instanceof DfaConstValue && ((DfaConstValue) value).getValue() == null) {
       setVariableState(dfaVar, getVariableState(dfaVar).withNullability(Nullness.NULLABLE));
     } else if (isNotNull(value) && !isNotNull(dfaVar)) {
       setVariableState(dfaVar, getVariableState(dfaVar).withNullability(Nullness.UNKNOWN));
       applyRelation(dfaVar, myFactory.getConstFactory().getNull(), true);
     }
   }
 }
Beispiel #6
0
  @Override
  public boolean isNull(DfaValue dfaValue) {
    if (dfaValue instanceof DfaConstValue) return ((DfaConstValue) dfaValue).getValue() == null;

    if (dfaValue instanceof DfaVariableValue) {
      int c1Index = getEqClassIndex(dfaValue);
      return c1Index >= 0 && c1Index == getEqClassIndex(myFactory.getConstFactory().getNull());
    }

    return false;
  }
  @Nullable
  private DfaInstructionState[] handleRelationBinop(
      BinopInstruction instruction,
      DataFlowRunner runner,
      DfaMemoryState memState,
      DfaValue dfaRight,
      DfaValue dfaLeft) {
    DfaValueFactory factory = runner.getFactory();
    final Instruction next = runner.getInstruction(instruction.getIndex() + 1);
    DfaRelationValue dfaRelation =
        factory
            .getRelationFactory()
            .createRelation(dfaLeft, dfaRight, instruction.getOperationSign(), false);
    if (dfaRelation == null) {
      return null;
    }

    myCanBeNullInInstanceof.add(instruction);

    ArrayList<DfaInstructionState> states = new ArrayList<DfaInstructionState>();

    final DfaMemoryState trueCopy = memState.createCopy();
    if (trueCopy.applyCondition(dfaRelation)) {
      trueCopy.push(factory.getConstFactory().getTrue());
      instruction.setTrueReachable();
      states.add(new DfaInstructionState(next, trueCopy));
    }

    //noinspection UnnecessaryLocalVariable
    DfaMemoryState falseCopy = memState;
    if (falseCopy.applyCondition(dfaRelation.createNegated())) {
      falseCopy.push(factory.getConstFactory().getFalse());
      instruction.setFalseReachable();
      states.add(new DfaInstructionState(next, falseCopy));
      if (instruction instanceof InstanceofInstruction && !falseCopy.isNull(dfaLeft)) {
        myUsefulInstanceofs.add((InstanceofInstruction) instruction);
      }
    }

    return states.toArray(new DfaInstructionState[states.size()]);
  }
 protected boolean checkNotNullable(
     DfaMemoryState state, DfaValue value, NullabilityProblem problem, PsiElement anchor) {
   boolean notNullable = state.checkNotNullable(value);
   if (notNullable
       && problem != NullabilityProblem.passingNullableArgumentToNonAnnotatedParameter) {
     DfaValueFactory factory = ((DfaMemoryStateImpl) state).getFactory();
     state.applyCondition(
         factory
             .getRelationFactory()
             .createRelation(value, factory.getConstFactory().getNull(), NE, false));
   }
   return notNullable;
 }
Beispiel #9
0
  @Override
  public boolean checkNotNullable(DfaValue value) {
    if (value == myFactory.getConstFactory().getNull()) return false;
    if (value instanceof DfaTypeValue && ((DfaTypeValue) value).isNullable()) return false;

    if (value instanceof DfaVariableValue) {
      DfaVariableValue varValue = (DfaVariableValue) value;
      if (varValue.getVariableType() instanceof PsiPrimitiveType) return true;
      if (isNotNull(varValue)) return true;
      if (getVariableState(varValue).isNullable()) return false;
    }
    return true;
  }
  @NotNull
  private DfaValue getMethodResultValue(
      MethodCallInstruction instruction,
      @Nullable DfaValue qualifierValue,
      DfaValueFactory factory) {
    DfaValue precalculated = instruction.getPrecalculatedReturnValue();
    if (precalculated != null) {
      return precalculated;
    }

    final PsiType type = instruction.getResultType();
    final MethodCallInstruction.MethodType methodType = instruction.getMethodType();

    if (methodType == MethodCallInstruction.MethodType.UNBOXING) {
      return factory.getBoxedFactory().createUnboxed(qualifierValue);
    }

    if (methodType == MethodCallInstruction.MethodType.BOXING) {
      DfaValue boxed = factory.getBoxedFactory().createBoxed(qualifierValue);
      return boxed == null ? factory.createTypeValue(type, Nullness.NOT_NULL) : boxed;
    }

    if (methodType == MethodCallInstruction.MethodType.CAST) {
      assert qualifierValue != null;
      if (qualifierValue instanceof DfaConstValue) {
        Object casted =
            TypeConversionUtil.computeCastTo(((DfaConstValue) qualifierValue).getValue(), type);
        return factory
            .getConstFactory()
            .createFromValue(casted, type, ((DfaConstValue) qualifierValue).getConstant());
      }
      return qualifierValue;
    }

    if (type != null && (type instanceof PsiClassType || type.getArrayDimensions() > 0)) {
      Nullness nullability = myReturnTypeNullability.get(instruction);
      if (nullability == Nullness.UNKNOWN && factory.isUnknownMembersAreNullable()) {
        nullability = Nullness.NULLABLE;
      }
      return factory.createTypeValue(type, nullability);
    }
    return DfaUnknownValue.getInstance();
  }
Beispiel #11
0
 private boolean checkCompareWithBooleanLiteral(
     DfaValue dfaLeft, DfaValue dfaRight, boolean negated) {
   if (dfaRight instanceof DfaConstValue) {
     Object constVal = ((DfaConstValue) dfaRight).getValue();
     if (constVal instanceof Boolean) {
       DfaConstValue negVal =
           myFactory
               .getConstFactory()
               .createFromValue(!((Boolean) constVal).booleanValue(), PsiType.BOOLEAN, null);
       if (!applyRelation(dfaLeft, negVal, !negated)) {
         return false;
       }
       if (!applyRelation(dfaLeft.createNegated(), negVal, negated)) {
         return false;
       }
     }
   }
   return true;
 }
  private List<DfaMemoryState> addContractResults(
      DfaValue[] argValues,
      MethodContract contract,
      List<DfaMemoryState> states,
      MethodCallInstruction instruction,
      DfaValueFactory factory,
      Set<DfaMemoryState> finalStates) {
    DfaConstValue.Factory constFactory = factory.getConstFactory();
    List<DfaMemoryState> falseStates = ContainerUtil.newArrayList();
    for (int i = 0; i < argValues.length; i++) {
      DfaValue argValue = argValues[i];
      MethodContract.ValueConstraint constraint = contract.arguments[i];
      DfaConstValue expectedValue = constraint.getComparisonValue(factory);
      if (expectedValue == null) continue;

      boolean invertCondition = constraint.shouldUseNonEqComparison();
      DfaValue condition =
          factory
              .getRelationFactory()
              .createRelation(argValue, expectedValue, EQEQ, invertCondition);
      if (condition == null) {
        if (!(argValue instanceof DfaConstValue)) {
          for (DfaMemoryState state : states) {
            falseStates.add(state.createCopy());
          }
          continue;
        }
        condition =
            constFactory.createFromValue(
                (argValue == expectedValue) != invertCondition, PsiType.BOOLEAN, null);
      }

      List<DfaMemoryState> nextStates = ContainerUtil.newArrayList();
      for (DfaMemoryState state : states) {
        boolean unknownVsNull =
            expectedValue == constFactory.getNull()
                && argValue instanceof DfaVariableValue
                && ((DfaMemoryStateImpl) state)
                        .getVariableState((DfaVariableValue) argValue)
                        .getNullability()
                    == Nullness.UNKNOWN;
        DfaMemoryState falseCopy = state.createCopy();
        if (state.applyCondition(condition)) {
          if (unknownVsNull && !invertCondition) {
            state.markEphemeral();
          }
          nextStates.add(state);
        }
        if (falseCopy.applyCondition(condition.createNegated())) {
          if (unknownVsNull && invertCondition) {
            falseCopy.markEphemeral();
          }
          falseStates.add(falseCopy);
        }
      }
      states = nextStates;
    }

    for (DfaMemoryState state : states) {
      state.push(getDfaContractReturnValue(contract, instruction, factory));
      finalStates.add(state);
    }

    return falseStates;
  }
Beispiel #13
0
  private boolean applyRelationCondition(@NotNull DfaRelationValue dfaRelation) {
    DfaValue dfaLeft = dfaRelation.getLeftOperand();
    DfaValue dfaRight = dfaRelation.getRightOperand();
    if (dfaLeft instanceof DfaUnknownValue || dfaRight instanceof DfaUnknownValue) return true;

    boolean isNegated = dfaRelation.isNegated();
    if (dfaLeft instanceof DfaTypeValue
        && ((DfaTypeValue) dfaLeft).isNotNull()
        && dfaRight == myFactory.getConstFactory().getNull()) {
      return isNegated;
    }

    if (dfaRight instanceof DfaTypeValue) {
      if (dfaLeft instanceof DfaVariableValue) {
        DfaVariableValue dfaVar = (DfaVariableValue) dfaLeft;
        if (isUnknownState(dfaVar)) return true;

        if (!dfaRelation.isInstanceOf()) {
          if (((DfaTypeValue) dfaRight).isNotNull() && isNull(dfaVar)) {
            return isNegated;
          }
          return true;
        }

        if (isNegated) {
          DfaVariableState newState =
              getVariableState(dfaVar).withNotInstanceofValue((DfaTypeValue) dfaRight);
          if (newState != null) {
            setVariableState(dfaVar, newState);
            return true;
          }
          return !getVariableState(dfaVar).isNotNull()
              && applyRelation(dfaVar, myFactory.getConstFactory().getNull(), false);
        }
        if (applyRelation(dfaVar, myFactory.getConstFactory().getNull(), true)) {
          DfaVariableState newState =
              getVariableState(dfaVar).withInstanceofValue((DfaTypeValue) dfaRight);
          if (newState != null) {
            setVariableState(dfaVar, newState);
            return true;
          }
        }
        return false;
      }
      return true;
    }

    if (isEffectivelyNaN(dfaLeft) || isEffectivelyNaN(dfaRight)) {
      applyEquivalenceRelation(dfaRelation, dfaLeft, dfaRight);
      return isNegated;
    }
    if (canBeNaN(dfaLeft) && canBeNaN(dfaRight)) {
      if (dfaLeft == dfaRight
          && dfaLeft instanceof DfaVariableValue
          && !(((DfaVariableValue) dfaLeft).getVariableType() instanceof PsiPrimitiveType)) {
        return !isNegated;
      }

      applyEquivalenceRelation(dfaRelation, dfaLeft, dfaRight);
      return true;
    }

    return applyEquivalenceRelation(dfaRelation, dfaLeft, dfaRight);
  }