com.ibm.wala.ssa

Class SymbolTable

java.lang.Object

com.ibm.wala.ssa.SymbolTable

All Implemented Interfaces:

java.lang.Cloneable

public class SymbolTable
extends java.lang.Object
implements java.lang.Cloneable

A symbol table which associates information with each variable (value number) in an SSA IR.

By convention, symbol numbers start at 1 ... the "this" parameter will be symbol number 1 in a virtual method.

This class is used heavily during SSA construction by SSABuilder.

Constructor Summary

Constructors

Constructor and Description
SymbolTable(int numberOfParameters)

Method Summary

Modifier and Type	Method and Description
SymbolTable	copy()
void	ensureSymbol(int i) ensure that the symbol table has allocated space for the particular value number
int	getConstant(boolean b)
int	getConstant(double d)
int	getConstant(float f)
int	getConstant(int i)
int	getConstant(long l)
int	getConstant(java.lang.String s)
java.lang.Object	getConstantValue(int v)
int	getDefaultValue(int vn)
double	getDoubleValue(int v)
float	getFloatValue(int v)
int	getIntValue(int v)
long	getLongValue(int v)
int	getMaxValueNumber()
int	getNullConstant()
int	getNumberOfParameters()
int	getOtherConstant(java.lang.Object v)
int	getParameter(int i) Return the value number of the ith parameter
int[]	getParameterValueNumbers()
PhiValue	getPhiValue(int valueNumber) Return the PhiValue that is associated with a given value number
java.lang.String	getStringValue(int v)
Value	getValue(int valueNumber)
java.lang.String	getValueString(int valueNumber)
boolean	isBooleanConstant(int v)
boolean	isBooleanOrZeroOneConstant(int v)
boolean	isConstant(int v)
boolean	isDoubleConstant(int v)
boolean	isFalse(int v)
boolean	isFloatConstant(int v)
boolean	isIntegerConstant(int v)
boolean	isLongConstant(int v)
boolean	isNullConstant(int v)
boolean	isNumberConstant(int v)
boolean	isOne(int v)
boolean	isOneOrTrue(int v)
boolean	isParameter(int valueNumber)
boolean	isStringConstant(int v)
boolean	isTrue(int v)
boolean	isZero(int v)
boolean	isZeroOrFalse(int v)
int	newPhi(int[] rhs)
int	newSymbol() Method newSymbol.
void	setConstantValue(int vn, ConstantValue val)
void	setDefaultValue(int vn, java.lang.Object defaultValue) Set the default value for a value number.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SymbolTable

public SymbolTable(int numberOfParameters)

Parameters:

numberOfParameters - in the IR .. should be ir.getNumberOfParameters()

Method Detail

newSymbol

public int newSymbol()

Method newSymbol.

Returns:

int

setConstantValue

public void setConstantValue(int vn,
                             ConstantValue val)

setDefaultValue

public void setDefaultValue(int vn,
                            java.lang.Object defaultValue)

Set the default value for a value number. The notion of a default value is for use by languages that do not require variables to be defined before they are used. In this situation, SSA conversion can fail since it depends on the assumption that values are always defined when used. The default value is the constant to be used in cases when a given value is used without having been defined. Currently, this is used only by CAst front ends for languages with this "feature".

getDefaultValue

public int getDefaultValue(int vn)

getNullConstant

public int getNullConstant()

getConstant

public int getConstant(boolean b)

getConstant

public int getConstant(int i)

getConstant

public int getConstant(long l)

getConstant

public int getConstant(float f)

getConstant

public int getConstant(double d)

getOtherConstant

public int getOtherConstant(java.lang.Object v)

getConstant

public int getConstant(java.lang.String s)

getParameter

public int getParameter(int i)
                 throws java.lang.IllegalArgumentException

Return the value number of the ith parameter

By convention, for a non-static method, the 0th parameter is 'this'

Throws:

java.lang.IllegalArgumentException

ensureSymbol

public void ensureSymbol(int i)

ensure that the symbol table has allocated space for the particular value number

Parameters:

i - a value number

getValueString

public java.lang.String getValueString(int valueNumber)

isConstant

public boolean isConstant(int v)

isZero

public boolean isZero(int v)

isOne

public boolean isOne(int v)

isTrue

public boolean isTrue(int v)

isZeroOrFalse

public boolean isZeroOrFalse(int v)

isOneOrTrue

public boolean isOneOrTrue(int v)

isFalse

public boolean isFalse(int v)

isBooleanOrZeroOneConstant

public boolean isBooleanOrZeroOneConstant(int v)

isBooleanConstant

public boolean isBooleanConstant(int v)

isIntegerConstant

public boolean isIntegerConstant(int v)

isLongConstant

public boolean isLongConstant(int v)

isFloatConstant

public boolean isFloatConstant(int v)

isDoubleConstant

public boolean isDoubleConstant(int v)

isNumberConstant

public boolean isNumberConstant(int v)

isStringConstant

public boolean isStringConstant(int v)

isNullConstant

public boolean isNullConstant(int v)

newPhi

public int newPhi(int[] rhs)
           throws java.lang.IllegalArgumentException

Throws:

java.lang.IllegalArgumentException - if rhs is null

getPhiValue

public PhiValue getPhiValue(int valueNumber)

Return the PhiValue that is associated with a given value number

getMaxValueNumber

public int getMaxValueNumber()

getParameterValueNumbers

public int[] getParameterValueNumbers()

getNumberOfParameters

public int getNumberOfParameters()

getStringValue

public java.lang.String getStringValue(int v)
                                throws java.lang.IllegalArgumentException

Throws:

java.lang.IllegalArgumentException

getFloatValue

public float getFloatValue(int v)
                    throws java.lang.IllegalArgumentException

Throws:

java.lang.IllegalArgumentException

getDoubleValue

public double getDoubleValue(int v)
                      throws java.lang.IllegalArgumentException

Throws:

java.lang.IllegalArgumentException

getIntValue

public int getIntValue(int v)
                throws java.lang.IllegalArgumentException

Throws:

java.lang.IllegalArgumentException

getLongValue

public long getLongValue(int v)
                  throws java.lang.IllegalArgumentException

Throws:

java.lang.IllegalArgumentException

getConstantValue

public java.lang.Object getConstantValue(int v)
                                  throws java.lang.IllegalArgumentException

Throws:

java.lang.IllegalArgumentException

getValue

public Value getValue(int valueNumber)

Returns:

the Value object for given value number or null if we have no special information about the value

isParameter

public boolean isParameter(int valueNumber)

Returns:

true iff this valueNumber is a parameter

copy

public SymbolTable copy()