org.jikesrvm.adaptive.measurements.instrumentation

Class CounterArrayManager

java.lang.Object

org.jikesrvm.compilers.opt.InstrumentedEventCounterManager

org.jikesrvm.adaptive.measurements.instrumentation.CounterArrayManager

public final class CounterArrayManager
extends InstrumentedEventCounterManager

An implementation of a InstrumentedEventCounterManager . It uses an unsynchronized two dimensional array of doubles to allocate its counters. (see InstrumentedEventCounterManager.java for a description of a counter manager)

NOTE: Much of this class was stolen from CounterArray.java, which is now gone.

Field Summary

Fields

Modifier and Type	Field and Description
(package private) static double[][]	counterArrays
(package private) static boolean	DEBUG
(package private) static int	INCREMENT
(package private) static int	INITIAL_COUNT Implementation
(package private) static int	numCounterArrays

Constructor Summary

Constructors

Constructor and Description
CounterArrayManager()

Method Summary

Modifier and Type	Method and Description
Instruction	createEventCounterInstruction(int handle, int index, double incrementValue) Create a place holder instruction to represent the counted event.
(package private) static void	decay(int handle, double rate) decay counters
private static void	expandCounterArrays() increment the number of counter arrays
double	getCounter(int handle, int index)
(package private) static RegisterOperand	InsertALoadOffset(Instruction s, IR ir, Operator operator, TypeReference type, Operand reg2, int offset) Insert array load off before s in the instruction stream.
void	insertBaselineCounter() Still under construction.
void	mutateOptEventCounterInstruction(Instruction counterInst, IR ir) Take an event counter instruction and mutate it into IR instructions that will do the actual counting.
int	registerCounterSpace(int countersNeeded) This method is called by a ManagedCounterData object to obtain space in the counter manager.
void	resizeCounterSpace(int handle, int countersNeeded) This method is called to change the number of counters needed.
void	setCounter(int handle, int index, double value) Sets the value of a counter.

Methods inherited from class java.lang.Object

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

Field Detail

DEBUG

static final boolean DEBUG

See Also:

Constant Field Values

INITIAL_COUNT

static final int INITIAL_COUNT

Implementation

See Also:

Constant Field Values

INCREMENT

static final int INCREMENT

See Also:

Constant Field Values

numCounterArrays

static int numCounterArrays

counterArrays

static double[][] counterArrays

Constructor Detail

CounterArrayManager

public CounterArrayManager()

Method Detail

registerCounterSpace

public int registerCounterSpace(int countersNeeded)

This method is called by a ManagedCounterData object to obtain space in the counter manager. A handle or "ID" is returned for the data to identify its counter space.

Specified by:

registerCounterSpace in class InstrumentedEventCounterManager

Parameters:

countersNeeded - The number of counters being requested

Returns:

The handle for this data's counter space.

resizeCounterSpace

public void resizeCounterSpace(int handle,
                               int countersNeeded)

Description copied from class: InstrumentedEventCounterManager

This method is called to change the number of counters needed.

Specified by:

resizeCounterSpace in class InstrumentedEventCounterManager

Parameters:

handle - The handle describing which the data to be resized

countersNeeded - The number of counters needed

getCounter

public double getCounter(int handle,
                         int index)

Specified by:

getCounter in class InstrumentedEventCounterManager

Parameters:

handle - The counter space to look in

index - The counter whose value to return

Returns:

the value of a counter.

setCounter

public void setCounter(int handle,
                       int index,
                       double value)

Description copied from class: InstrumentedEventCounterManager

Sets the value of a counter.

Specified by:

setCounter in class InstrumentedEventCounterManager

Parameters:

handle - The counter space to look in

index - The counter whose value to return

value - The new value of the counter

createEventCounterInstruction

public Instruction createEventCounterInstruction(int handle,
                                                 int index,
                                                 double incrementValue)

Create a place holder instruction to represent the counted event.

Specified by:

createEventCounterInstruction in class InstrumentedEventCounterManager

Parameters:

handle - The handle of the array for the method

index - Index within that array

incrementValue - The value to add to the counter

Returns:

The counter instruction

mutateOptEventCounterInstruction

public void mutateOptEventCounterInstruction(Instruction counterInst,
                                             IR ir)

Take an event counter instruction and mutate it into IR instructions that will do the actual counting. Precondition: IR is in LIR

Specified by:

mutateOptEventCounterInstruction in class InstrumentedEventCounterManager

Parameters:

counterInst - The counter instruction to mutate

ir - The governing IR

InsertALoadOffset

static RegisterOperand InsertALoadOffset(Instruction s,
                                         IR ir,
                                         Operator operator,
                                         TypeReference type,
                                         Operand reg2,
                                         int offset)

Insert array load off before s in the instruction stream.

Parameters:

s - the instruction to insert before

ir - the containing IR

operator - the operator to insert

type - the type of the result

reg2 - the base to load from

offset - the offset to load at

Returns:

the result operand of the inserted instruction

insertBaselineCounter

public void insertBaselineCounter()

Still under construction.

Specified by:

insertBaselineCounter in class InstrumentedEventCounterManager

decay

static void decay(int handle,
                  double rate)

decay counters

Parameters:

handle - The identifier of the counter array to decay

rate - The rate at which to decay, i.e. a value of 2 will divide all values in half

expandCounterArrays

private static void expandCounterArrays()

increment the number of counter arrays