use of soot.dava.internal.AST.ASTOrCondition in project soot by Sable.
the class SimplifyConditions method applyDeMorgans.
/*
* !z0 && !z1 ----> !(z0 || z1)
* !z0 || !z1 ----> !(z0 && z1)
*
* Send null if no change else send new condition CONDITION
*/
public ASTCondition applyDeMorgans(ASTAggregatedCondition aggCond) {
ASTCondition left = aggCond.getLeftOp();
ASTCondition right = aggCond.getRightOp();
if (aggCond.isNotted() && left instanceof ASTBinaryCondition && right instanceof ASTBinaryCondition) {
// we can remove the not sign by simply flipping the two conditions
// ! ( x==y && a<b )
left.flip();
right.flip();
if (aggCond instanceof ASTAndCondition)
aggCond = new ASTOrCondition(left, right);
else
aggCond = new ASTAndCondition(left, right);
return aggCond;
}
if ((left.isNotted() && right.isNotted() && (!(left instanceof ASTBinaryCondition) && !(right instanceof ASTBinaryCondition))) || (left.isNotted() && aggCond.isNotted() && !(left instanceof ASTBinaryCondition)) || (right.isNotted() && aggCond.isNotted() && !(right instanceof ASTBinaryCondition))) {
// both are notted and atleast one is not a binaryCondition
left.flip();
right.flip();
ASTAggregatedCondition newCond;
if (aggCond instanceof ASTAndCondition)
newCond = new ASTOrCondition(left, right);
else
newCond = new ASTAndCondition(left, right);
if (aggCond.isNotted())
return newCond;
else {
newCond.flip();
return newCond;
}
}
return null;
}
use of soot.dava.internal.AST.ASTOrCondition in project soot by Sable.
the class SimplifyConditions method simplifyIfAtleastOneConstant.
/*
* When this method is invoked we are sure that there are no occurences of !true or !false since
* this is AFTER doing depth first of the children so the unaryCondition must have simplified the above
*
* Return Null if no change else return changed condition
*/
public ASTCondition simplifyIfAtleastOneConstant(ASTAggregatedCondition aggCond) {
ASTCondition left = aggCond.getLeftOp();
ASTCondition right = aggCond.getRightOp();
Boolean leftBool = null;
Boolean rightBool = null;
if (left instanceof ASTUnaryCondition)
leftBool = isBooleanConstant(((ASTUnaryCondition) left).getValue());
if (right instanceof ASTUnaryCondition)
rightBool = isBooleanConstant(((ASTUnaryCondition) right).getValue());
/*
* a && b NOCHANGE DONE
* b && a NOCHANGE DONE
*
* a || b NOCHANGE DONE
* b || a NOCHANGE DONE
*
*/
if (leftBool == null && rightBool == null) {
// meaning both are not constants
return null;
}
if (aggCond instanceof ASTAndCondition) {
if (leftBool != null && rightBool != null) {
// meaning both are constants
if (leftBool.booleanValue() && rightBool.booleanValue()) {
// both are true
return new ASTUnaryCondition(DIntConstant.v(1, BooleanType.v()));
} else {
// atleast one of the two is false
return new ASTUnaryCondition(DIntConstant.v(0, BooleanType.v()));
}
}
if (leftBool != null) {
// condition passed
if (leftBool.booleanValue()) {
// condition.......just return the right condition
return right;
} else {
// return a unary false
return new ASTUnaryCondition(DIntConstant.v(0, BooleanType.v()));
}
}
if (rightBool != null) {
// implicityly means that the leftBool is null
if (rightBool.booleanValue()) {
// rightBool is true so it all depends on left
return left;
} else {
// remove the leftBool since there might be side effects
return aggCond;
}
}
} else if (aggCond instanceof ASTOrCondition) {
/*
*
* true || false ---> true DONE
* true || true --> true DONE
* false || true --> true DONE
* false || false ---> false DONE
*
*
* true || b ----> true DONE
* false || b -----> b DONE
*
* b || true ---> b || true .... although we know the condition is true we have to evaluate b because of possible side effects DONE
* b || false ---> b DONE
*
*/
if (leftBool != null && rightBool != null) {
// meaning both are constants
if (!leftBool.booleanValue() && !rightBool.booleanValue()) {
// both are false
return new ASTUnaryCondition(DIntConstant.v(0, BooleanType.v()));
} else {
// atleast one of the two is true
return new ASTUnaryCondition(DIntConstant.v(1, BooleanType.v()));
}
}
if (leftBool != null) {
// condition passed
if (leftBool.booleanValue()) {
// left bool is true that means we will stop evaluation of condition, just return true
return new ASTUnaryCondition(DIntConstant.v(1, BooleanType.v()));
} else {
// left bool is false so we have to continue evaluating right
return right;
}
}
if (rightBool != null) {
// implicityly means that the leftBool is null
if (rightBool.booleanValue()) {
// rightBool is true but leftBool must be evaluated beforehand
return aggCond;
} else {
// rightBool is false so everything depends on left
return left;
}
}
} else
throw new RuntimeException("Found unknown aggregated condition");
return null;
}
Aggregations