org.jikesrvm.ia32

Class Registers

java.lang.Object

org.jikesrvm.architecture.AbstractRegisters

org.jikesrvm.ia32.Registers

public final class Registers
extends AbstractRegisters

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
Address	fp Frame pointer

Fields inherited from class org.jikesrvm.architecture.AbstractRegisters

ip

Constructor Summary

Constructors

Constructor and Description
Registers()

Method Summary

Modifier and Type	Method and Description
void	adjustESP(Offset delta, boolean traceAdjustments) A thread's stack has been moved or resized.
void	clear() Zeroes all registers
void	dump()
Address	getInnermostFramePointer()
Address	getInnermostInstructionAddress()
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
void	setInnermost() set ip and fp values to those of the caller. used just prior to entering sigwait to set fp & ip so that GC will scan the threads stack starting at the frame of the method that called sigwait.
void	setInnermost(Address newip, Address newfp) Sets 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	unwindStackFrame() Updates the machine state as if the stackframe were unwound.

Methods inherited from class org.jikesrvm.architecture.AbstractRegisters

getFPRs, getGPRs, getInUse, getIP, getIPLocation, setInUse, setIP

Methods inherited from class java.lang.Object

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

Field Detail

fp

public Address fp

Frame pointer

Constructor Detail

Registers

public Registers()

Method Detail

clear

public void clear()

Description copied from class: AbstractRegisters

Zeroes all registers

Overrides:

clear in class AbstractRegisters

getInnermostFramePointer

public Address getInnermostFramePointer()

Specified by:

getInnermostFramePointer in class AbstractRegisters

Returns:

framepointer for the deepest stackframe

getInnermostInstructionAddress

public Address getInnermostInstructionAddress()

Specified by:

getInnermostInstructionAddress in class AbstractRegisters

Returns:

next instruction address for the deepest stackframe

unwindStackFrame

public void unwindStackFrame()

Updates the machine state as if the stackframe were unwound.

Specified by:

unwindStackFrame in class AbstractRegisters

setInnermost

public void setInnermost(Address newip,
                         Address newfp)

Sets 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.

Specified by:

setInnermost in class AbstractRegisters

Parameters:

newip - the new instruction pointer

newfp - the new frame pointer

setInnermost

public void setInnermost()

set ip and fp values to those of the caller. used just prior to entering sigwait to set fp & ip so that GC will scan the threads stack starting at the frame of the method that called sigwait.

initializeStack

public 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

Specified by:

initializeStack in class AbstractRegisters

Parameters:

ip - The instruction pointer for the "startoff" method

sp - The base of the stack

adjustESP

public void adjustESP(Offset delta,
                      boolean traceAdjustments)

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

Specified by:

adjustESP in class AbstractRegisters

Parameters:

delta - The displacement to be applied

traceAdjustments - Log all adjustments to stderr if true

dump

public void dump()

Overrides:

dump in class AbstractRegisters