gov.nasa.jpf.jvm.bytecode

Class JVMReturnInstruction

java.lang.Object

gov.nasa.jpf.vm.Instruction

gov.nasa.jpf.vm.bytecode.ReturnInstruction

gov.nasa.jpf.jvm.bytecode.JVMReturnInstruction

All Implemented Interfaces:

JVMInstruction, Attributable, InstructionInterface, java.lang.Cloneable

Direct Known Subclasses:

ARETURN, FRETURN, IRETURN, LongReturn, NATIVERETURN, RETURN

public abstract class JVMReturnInstruction
extends ReturnInstruction
implements JVMInstruction

abstraction for the various return instructions

Field Summary

Fields

Modifier and Type	Field and Description
protected StackFrame	returnFrame

Fields inherited from class gov.nasa.jpf.vm.Instruction

attr, insnIndex, mi, position

Constructor Summary

Constructors

Constructor and Description
JVMReturnInstruction()

Method Summary

Modifier and Type	Method and Description
void	accept(JVMInstructionVisitor insVisitor)
void	addReturnAttr(ThreadInfo ti, java.lang.Object attr)
void	cleanupTransients() this is important since keeping the StackFrame alive would be a major memory leak
Instruction	execute(ThreadInfo ti) this is the real workhorse returns next instruction to enter in this thread <2do> it's unfortunate we roll every side effect into this method, because it diminishes the value of the 'executeInstruction' notification: all insns that require some sort of late binding (InvokeVirtual, GetField, ..) are not yet fully analyzable (e.g.
protected abstract void	getAndSaveReturnValue(StackFrame frame)
<T> T	getNextReturnAttr(ThreadInfo ti, java.lang.Class<T> type, java.lang.Object prev)
java.lang.Object	getReturnAttr(ThreadInfo ti) this returns all of them - use either if you know there will be only one attribute at a time, or check/process result with ObjectList obviously, this only makes sense from an instructionExecuted(), since the value is pushed during the enter().
<T> T	getReturnAttr(ThreadInfo ti, java.lang.Class<T> type) this only returns the first attr of this type, there can be more if you don't use client private types or the provided type is too general
protected abstract java.lang.Object	getReturnedOperandAttr(StackFrame frame)
StackFrame	getReturnFrame()
abstract int	getReturnTypeSize()
abstract java.lang.Object	getReturnValue(ThreadInfo ti)
boolean	hasReturnAttr(ThreadInfo ti)
boolean	hasReturnAttr(ThreadInfo ti, java.lang.Class<?> type)
protected abstract void	pushReturnValue(StackFrame frame)
java.util.Iterator<?>	returnAttrIterator(ThreadInfo ti)
<T> java.util.Iterator<T>	returnAttrIterator(ThreadInfo ti, java.lang.Class<T> type)
void	setReturnAttr(ThreadInfo ti, java.lang.Object a) this replaces all of them - use only if you know - there will be only one attribute at a time - you obtained the value you set by a previous getXAttr() - you constructed a multi value list with ObjectList.createList() we don't clone since pushing a return value already changed the caller frame
void	setReturnFrame(StackFrame frame)
java.lang.String	toPostExecString() this can contain additional info that was gathered/cached during execution

Methods inherited from class gov.nasa.jpf.vm.Instruction

addAttr, asInstruction, attrIterator, attrIterator, getAttr, getAttr, getFileLocation, getFilePos, getInstructionIndex, getLength, getLineNumber, getMethodInfo, getMnemonic, getNext, getNext, getNextAttr, getPosition, getPrev, getSourceLine, getSourceLocation, getSourceOrLocation, hasAttr, hasAttr, init, isBackJump, isCompleted, isExtendedInstruction, isFirstInstruction, isMonitorEnterPrologue, isSchedulingRelevant, removeAttr, replaceAttr, requiresClinitExecution, setAttr, setContext, setLocation, setMethodInfo, toString, typeSafeClone

Methods inherited from class java.lang.Object

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

Methods inherited from interface gov.nasa.jpf.vm.bytecode.InstructionInterface

asInstruction, getByteCode, getFileLocation, getFilePos, getInstructionIndex, getLength, getLineNumber, getMethodInfo, getMnemonic, getNext, getNext, getPosition, getPrev, getSourceLine, getSourceLocation, isBackJump, isCompleted, isExtendedInstruction, isFirstInstruction

Methods inherited from interface gov.nasa.jpf.util.Attributable

addAttr, attrIterator, attrIterator, getAttr, getAttr, getNextAttr, hasAttr, hasAttr, removeAttr, replaceAttr, setAttr

Field Detail

returnFrame

protected StackFrame returnFrame

Constructor Detail

JVMReturnInstruction

public JVMReturnInstruction()

Method Detail

getReturnTypeSize

public abstract int getReturnTypeSize()

getReturnedOperandAttr

protected abstract java.lang.Object getReturnedOperandAttr(StackFrame frame)

getAndSaveReturnValue

protected abstract void getAndSaveReturnValue(StackFrame frame)

pushReturnValue

protected abstract void pushReturnValue(StackFrame frame)

getReturnValue

public abstract java.lang.Object getReturnValue(ThreadInfo ti)

getReturnFrame

public StackFrame getReturnFrame()

setReturnFrame

public void setReturnFrame(StackFrame frame)

cleanupTransients

public void cleanupTransients()

this is important since keeping the StackFrame alive would be a major memory leak

Overrides:

cleanupTransients in class Instruction

hasReturnAttr

public boolean hasReturnAttr(ThreadInfo ti)

hasReturnAttr

public boolean hasReturnAttr(ThreadInfo ti,
                             java.lang.Class<?> type)

getReturnAttr

public java.lang.Object getReturnAttr(ThreadInfo ti)

this returns all of them - use either if you know there will be only one attribute at a time, or check/process result with ObjectList obviously, this only makes sense from an instructionExecuted(), since the value is pushed during the enter(). Use ObjectList to access values

setReturnAttr

public void setReturnAttr(ThreadInfo ti,
                          java.lang.Object a)

this replaces all of them - use only if you know - there will be only one attribute at a time - you obtained the value you set by a previous getXAttr() - you constructed a multi value list with ObjectList.createList() we don't clone since pushing a return value already changed the caller frame

addReturnAttr

public void addReturnAttr(ThreadInfo ti,
                          java.lang.Object attr)

getReturnAttr

public <T> T getReturnAttr(ThreadInfo ti,
                           java.lang.Class<T> type)

this only returns the first attr of this type, there can be more if you don't use client private types or the provided type is too general

getNextReturnAttr

public <T> T getNextReturnAttr(ThreadInfo ti,
                               java.lang.Class<T> type,
                               java.lang.Object prev)

returnAttrIterator

public java.util.Iterator<?> returnAttrIterator(ThreadInfo ti)

returnAttrIterator

public <T> java.util.Iterator<T> returnAttrIterator(ThreadInfo ti,
                                                    java.lang.Class<T> type)

execute

public Instruction execute(ThreadInfo ti)

Description copied from class: Instruction

this is the real workhorse returns next instruction to enter in this thread <2do> it's unfortunate we roll every side effect into this method, because it diminishes the value of the 'executeInstruction' notification: all insns that require some sort of late binding (InvokeVirtual, GetField, ..) are not yet fully analyzable (e.g. the callee of InvokeVirtuals is not known yet), putting the burden of duplicating the related code of enter() in the listener. It would be better if we factor this 'prepareExecution' out of enter()

Specified by:

execute in interface InstructionInterface

Specified by:

execute in class Instruction

accept

public void accept(JVMInstructionVisitor insVisitor)

Specified by:

accept in interface JVMInstruction

toPostExecString

public java.lang.String toPostExecString()

Description copied from class: Instruction

this can contain additional info that was gathered/cached during execution

Specified by:

toPostExecString in interface InstructionInterface

Overrides:

toPostExecString in class Instruction