cetus.hir
Class RangeExpression

java.lang.Object
  cetus.hir.Expression
      cetus.hir.RangeExpression

All Implemented Interfaces:

Printable, Traversable, java.lang.Cloneable, java.lang.Comparable<Expression>

public class RangeExpression
extends Expression

RangeExpression represents a symbolic range with a lower bound expression and an upper bound expression. RangeAnalysis uses RangeExpression to compute a valid value ranges of variables at program points.

Field Summary

Fields inherited from class cetus.hir.Expression

children, needs_parens, object_print_method, parent

Constructor Summary

RangeExpression(Expression lb, Expression ub)
Constructs a range expression with the given lower and upper bounds.

Method Summary

int	compareTo(Expression e) Compares the given expression with this range expression.
static void	defaultPrint(RangeExpression range, java.io.OutputStream stream) Default print method
boolean	equals(java.lang.Object o) Checks if the given object is equal to this range expression.
Expression	getLB() Returns the lower bound of this range expression.
static Expression	getOmega() Returns a new instanceof omega expression which is [-inf:inf].
Expression	getUB() Returns the upper bound of this range expression.
boolean	isBounded() Returns true if neither lb nor ub is infinity.
boolean	isEmpty() Checks if this range expression has a lower bound greater than the upper bound.
boolean	isOmega() Checks if this range expression does not have any closed bounds.
void	setLB(Expression lb) Sets the lower bound with the given expression.
void	setUB(Expression ub) Sets the upper bound with the given expression.
Expression	toExpression() Converts this range expression to a non-range expression if the lower bound is equal to the upper bound.
static RangeExpression	toRange(Expression e) Converts an arbitrary expression to a range expression by setting the same lower bound and upper bound.
java.lang.String	toString() Returns the string representation of the range expression.

Methods inherited from class cetus.hir.Expression

clone, equals2, findExpression, getChildren, getParent, getStatement, needsParens, print, printSelf, removeChild, setChild, setParens, setParent, setPrintMethod, swapWith, verify

Methods inherited from class java.lang.Object

finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

RangeExpression

public RangeExpression(Expression lb,
                       Expression ub)

Constructs a range expression with the given lower and upper bounds.

Parameters:

lb - the lower bound expression.

ub - the upper bound expression.

Method Detail

defaultPrint

public static void defaultPrint(RangeExpression range,
                                java.io.OutputStream stream)

Default print method

toString

public java.lang.String toString()

Returns the string representation of the range expression.

Overrides:

toString in class Expression

equals

public boolean equals(java.lang.Object o)

Checks if the given object is equal to this range expression.

Overrides:

equals in class Expression

Parameters:

o - the object to be compared.

compareTo

public int compareTo(Expression e)

Compares the given expression with this range expression.

Specified by:

compareTo in interface java.lang.Comparable<Expression>

Overrides:

compareTo in class Expression

Returns:

0 if they are equal, -1 otherwise.

setLB

public void setLB(Expression lb)

Sets the lower bound with the given expression.

Parameters:

lb - the new lower bound.

setUB

public void setUB(Expression ub)

Sets the upper bound with the given expression.

Parameters:

ub - the new upper bound

getLB

public Expression getLB()

Returns the lower bound of this range expression.

getUB

public Expression getUB()

Returns the upper bound of this range expression.

isEmpty

public boolean isEmpty()

Checks if this range expression has a lower bound greater than the upper bound. The comparison is possible only for literals and infinity expression.

isOmega

public boolean isOmega()

Checks if this range expression does not have any closed bounds.

isBounded

public boolean isBounded()

Returns true if neither lb nor ub is infinity.

toRange

public static RangeExpression toRange(Expression e)

Converts an arbitrary expression to a range expression by setting the same lower bound and upper bound.

toExpression

public Expression toExpression()

Converts this range expression to a non-range expression if the lower bound is equal to the upper bound.

getOmega

public static Expression getOmega()

Returns a new instanceof omega expression which is [-inf:inf].

Returns:

a new omega expression.