gov.nasa.jpf.jvm.bytecode

Class INVOKECLINIT

java.lang.Object

gov.nasa.jpf.vm.Instruction

gov.nasa.jpf.vm.bytecode.InvokeInstruction

gov.nasa.jpf.jvm.bytecode.JVMInvokeInstruction

gov.nasa.jpf.jvm.bytecode.INVOKESTATIC

gov.nasa.jpf.jvm.bytecode.INVOKECLINIT

All Implemented Interfaces:

JVMInstruction, Attributable, InstructionInterface, java.lang.Cloneable

public class INVOKECLINIT
extends INVOKESTATIC

this is an artificial bytecode that we use to deal with the particularities of calls, which are never in the loaded bytecode but always directly called by the VM. The most obvious difference is that execution does not trigger class initialization. A more subtle difference is that we save a wait() - if a class is concurrently initialized, both enter INVOKECLINIT (i.e. compete and sync for/on the class object lock), but once the second thread gets resumed and detects that the class is now initialized (by the first thread), it skips the method execution and returns right away (after deregistering as a lock contender). That's kind of hackish, but we have no method to do the wait in, unless we significantly complicate the direct call stubs, which would obfuscate observability (debugging dynamically generated code isn't very appealing).

Field Summary

Fields

Modifier and Type	Field and Description
static int	OPCODE

Fields inherited from class gov.nasa.jpf.jvm.bytecode.JVMInvokeInstruction

argSize, arguments, cname, invokedMethod, lastObj, mname, signature

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

attr, insnIndex, mi, position

Constructor Summary

Constructors

Constructor and Description
INVOKECLINIT(ClassInfo ci)

Method Summary

Modifier and Type	Method and Description
void	accept(JVMInstructionVisitor insVisitor)
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.
int	getByteCode()
boolean	isExtendedInstruction() is this one of our own, artificial insns?

Methods inherited from class gov.nasa.jpf.jvm.bytecode.INVOKESTATIC

getArgSize, getClassInfo, getClassObjectRef, getFieldValue, getInvokedClassInfo, getInvokedClassName, getInvokedMethod, getInvokedMethod, getStaticElementInfo, toPostExecString, toString, typeSafeClone

Methods inherited from class gov.nasa.jpf.jvm.bytecode.JVMInvokeInstruction

getArgumentAttrs, getArgumentValue, getArgumentValues, getFieldOrArgumentValue, getInvokedMethodClassName, getInvokedMethodName, getInvokedMethodSignature, getLastObjRef, getLength, getReturnType, getReturnTypeName, hasArgumentAttr, hasArgumentObjectAttr, isCompleted, isReferenceReturnType, setInvokedMethod, setupCallee

Methods inherited from class gov.nasa.jpf.vm.bytecode.InvokeInstruction

reschedulesLockAcquisition

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

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

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, getFileLocation, getFilePos, getInstructionIndex, getLineNumber, getMethodInfo, getMnemonic, getNext, getNext, getPosition, getPrev, getSourceLine, getSourceLocation, isBackJump, isFirstInstruction

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

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

Field Detail

OPCODE

public static final int OPCODE

See Also:

Constant Field Values

Constructor Detail

INVOKECLINIT

public INVOKECLINIT(ClassInfo ci)

Method Detail

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

Overrides:

execute in class INVOKESTATIC

isExtendedInstruction

public boolean isExtendedInstruction()

Description copied from class: Instruction

is this one of our own, artificial insns?

Specified by:

isExtendedInstruction in interface InstructionInterface

Overrides:

isExtendedInstruction in class Instruction

getByteCode

public int getByteCode()

Specified by:

getByteCode in interface InstructionInterface

Overrides:

getByteCode in class INVOKESTATIC

accept

public void accept(JVMInstructionVisitor insVisitor)

Specified by:

accept in interface JVMInstruction

Overrides:

accept in class INVOKESTATIC