edu.umd.cs.findbugs.ba.vna
Class LoadedFieldSet

java.lang.Object
  edu.umd.cs.findbugs.ba.vna.LoadedFieldSet

public class LoadedFieldSet
extends java.lang.Object

Object which stores which fields are loaded and stored by the instructions in a method (including through inner-class access methods), and also which fields are loaded/stored by the overall method. The main purpose is for doing redundant load elimination and forward substitution more efficiently, but it might be useful in other situations.

Author:

David Hovemeyer

Nested Class Summary

static class

LoadedFieldSet.LoadStoreCount Count number of times a field is loaded and/or stored in the method.

Constructor Summary

LoadedFieldSet(org.apache.bcel.generic.MethodGen methodGen)
Constructor.

Method Summary

void	addLoad(org.apache.bcel.generic.InstructionHandle handle, XField field) Add a load of given field at given instruction.
void	addStore(org.apache.bcel.generic.InstructionHandle handle, XField field) Add a store of given field at given instruction.
XField	getField(org.apache.bcel.generic.InstructionHandle handle) Get the field loaded or stored at given instruction, if any.
LoadedFieldSet.LoadStoreCount	getLoadStoreCount(XField field) Get the number of times given field is loaded and stored within the method.
boolean	instructionIsLoad(org.apache.bcel.generic.InstructionHandle handle) Return whether or not the given instruction is a load.
boolean	isLoaded(XField field) Return whether or not the given field is loaded by any instruction in the method.

Methods inherited from class java.lang.Object

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

Constructor Detail

LoadedFieldSet

public LoadedFieldSet(org.apache.bcel.generic.MethodGen methodGen)

Constructor. Constructs an empty object.

Parameters:

methodGen - the method being analyzed for loads/stores

Method Detail

getLoadStoreCount

public LoadedFieldSet.LoadStoreCount getLoadStoreCount(XField field)

Get the number of times given field is loaded and stored within the method.

Parameters:

field - the field

Returns:

the load/store count object

addLoad

public void addLoad(org.apache.bcel.generic.InstructionHandle handle,
                    XField field)

Add a load of given field at given instruction.

Parameters:

handle - the instruction

field - the field

addStore

public void addStore(org.apache.bcel.generic.InstructionHandle handle,
                     XField field)

Add a store of given field at given instruction.

Parameters:

handle - the instruction

field - the field

getField

public XField getField(org.apache.bcel.generic.InstructionHandle handle)

Get the field loaded or stored at given instruction, if any.

Parameters:

handle - the instruction

Returns:

the field loaded or stored at the instruction, or null if the instruction is not a load or store

isLoaded

public boolean isLoaded(XField field)

Return whether or not the given field is loaded by any instruction in the method.

Parameters:

field - the field

Returns:

true if the field is loaded somewhere in the method, false if it is never loaded

instructionIsLoad

public boolean instructionIsLoad(org.apache.bcel.generic.InstructionHandle handle)

Return whether or not the given instruction is a load.

Parameters:

handle - the instruction

Returns:

true if the instruction is a load, false if not