org.jikesrvm.architecture

Class AbstractRegisters

java.lang.Object

org.jikesrvm.architecture.AbstractRegisters

Direct Known Subclasses:

Registers

public abstract class AbstractRegisters
extends Object

The machine state comprising a thread's execution context, used both for thread context switching and for software/hardware exception reporting/delivery.

Field Summary

Fields

Modifier and Type	Field and Description
private double[]	fprs Floating point registers
private double[]	fprsShadow
private WordArray	gprs General purpose registers
private WordArray	gprsShadow
private boolean	inuse Do exception registers currently contain live values?
protected Address	ip Instruction address register

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractRegisters()

Method Summary

Modifier and Type	Method and Description
abstract void	adjustESP(Offset delta, boolean traceAdjustments) A thread's stack has been moved or resized.
void	clear() Zeroes all registers
protected void	dump()
double[]	getFPRs()
WordArray	getGPRs()
abstract Address	getInnermostFramePointer()
abstract Address	getInnermostInstructionAddress()
boolean	getInUse()
Address	getIP()
Address	getIPLocation()
abstract void	initializeStack(Address ip, Address sp) The following method initializes a thread stack as if "startoff" method had been called by an empty baseline-compiled "sentinel" frame with one local variable
abstract void	setInnermost(Address returnAddress, Address callerFramePointer) Set ip & fp. used to control the stack frame at which a scan of the stack during GC will start, for ex., the top java frame for a thread that is blocked in native code during GC.
void	setInUse(boolean b)
void	setIP(Address ip) Sets instruction address register.
abstract void	unwindStackFrame()

Methods inherited from class java.lang.Object

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

Field Detail

gprs

private final WordArray gprs

General purpose registers

gprsShadow

private final WordArray gprsShadow

fprs

private final double[] fprs

Floating point registers

fprsShadow

private final double[] fprsShadow

ip

protected Address ip

Instruction address register

inuse

private boolean inuse

Do exception registers currently contain live values? Set by C hardware exception handler and RuntimeEntrypoints.athrow and reset by each implementation of ExceptionDeliverer.deliverException

Constructor Detail

AbstractRegisters

protected AbstractRegisters()

Method Detail

getInUse

public final boolean getInUse()

setInUse

public final void setInUse(boolean b)

getGPRs

public final WordArray getGPRs()

getFPRs

public final double[] getFPRs()

getIP

public final Address getIP()

Returns:

Instruction address register

setIP

public final void setIP(Address ip)

Sets instruction address register.

Parameters:

ip - the new value for the instruction address register

getIPLocation

public final Address getIPLocation()

Returns:

memory location of IP register in this data structure

clear

public void clear()

Zeroes all registers

dump

protected void dump()

initializeStack

public abstract void initializeStack(Address ip,
                                     Address sp)

The following method initializes a thread stack as if "startoff" method had been called by an empty baseline-compiled "sentinel" frame with one local variable

Parameters:

ip - The instruction pointer for the "startoff" method

sp - The base of the stack

adjustESP

public abstract void adjustESP(Offset delta,
                               boolean traceAdjustments)

A thread's stack has been moved or resized. Adjust the ESP register to reflect new position.

Parameters:

delta - The displacement to be applied

traceAdjustments - Log all adjustments to stderr if true

setInnermost

public abstract void setInnermost(Address returnAddress,
                                  Address callerFramePointer)

Set ip & fp. used to control the stack frame at which a scan of the stack during GC will start, for ex., the top java frame for a thread that is blocked in native code during GC.

Parameters:

returnAddress - the new return address (i.e. ip)

callerFramePointer - the new frame pointer (i.e. fp)

getInnermostFramePointer

public abstract Address getInnermostFramePointer()

unwindStackFrame

public abstract void unwindStackFrame()

getInnermostInstructionAddress

public abstract Address getInnermostInstructionAddress()