org.jikesrvm.compilers.opt.regalloc

Class LinearScanPhase

java.lang.Object

org.jikesrvm.compilers.opt.driver.CompilerPhase

org.jikesrvm.compilers.opt.regalloc.LinearScanPhase

public final class LinearScanPhase
extends CompilerPhase

Field Summary

Fields

Modifier and Type	Field and Description
private static Constructor<CompilerPhase>	constructor
private SpillLocationManager	spillManager An object which manages spill location assignments.

Fields inherited from class org.jikesrvm.compilers.opt.driver.CompilerPhase

container

Constructor Summary

Constructors

Constructor and Description
LinearScanPhase()

Method Summary

Modifier and Type	Method and Description
private ActiveSet	createEmptySetOfActiveIntervals(IR ir)
private SpillCostEstimator	determineSpillCostEstimator(IR ir)
Constructor<CompilerPhase>	getClassConstructor() Get a constructor object for this compiler phase
String	getName()
void	perform(IR ir) Perform the linear scan register allocation algorithm.
boolean	printingEnabled(OptOptions options, boolean before) Returns true if the phase wants the IR dumped before and/or after it runs.
boolean	shouldPerform(OptOptions options) This method determines if the phase should be run, based on the Options object it is passed.

Methods inherited from class org.jikesrvm.compilers.opt.driver.CompilerPhase

dumpIR, dumpIR, getCompilerPhaseConstructor, getCompilerPhaseConstructor, newExecution, performPhase, reportAdditionalStats, setContainer, verify

Methods inherited from class java.lang.Object

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

Field Detail

spillManager

private SpillLocationManager spillManager

An object which manages spill location assignments.

constructor

private static final Constructor<CompilerPhase> constructor

Constructor Detail

LinearScanPhase

public LinearScanPhase()

Method Detail

getClassConstructor

public Constructor<CompilerPhase> getClassConstructor()

Get a constructor object for this compiler phase

Overrides:

getClassConstructor in class CompilerPhase

Returns:

compiler phase constructor

shouldPerform

public boolean shouldPerform(OptOptions options)

Description copied from class: CompilerPhase

This method determines if the phase should be run, based on the Options object it is passed. By default, phases are always performed. Subclasses should override this method if they only want to be performed conditionally.

Overrides:

shouldPerform in class CompilerPhase

Parameters:

options - the compiler options for the compilation

Returns:

true because register allocation is required

getName

public String getName()

Specified by:

getName in class CompilerPhase

Returns:

a String which is the name of the phase.

printingEnabled

public boolean printingEnabled(OptOptions options,
                               boolean before)

Description copied from class: CompilerPhase

Returns true if the phase wants the IR dumped before and/or after it runs. By default, printing is not enabled. Subclasses should override this method if they want to provide IR dumping.

Overrides:

printingEnabled in class CompilerPhase

Parameters:

options - the compiler options for the compilation

before - true when invoked before perform, false otherwise.

Returns:

true if the IR should be printed, false otherwise.

perform

public void perform(IR ir)

Perform the linear scan register allocation algorithm.

See TOPLAS 21(5), Sept 1999, p 895-913

Specified by:

perform in class CompilerPhase

Parameters:

ir - the IR

createEmptySetOfActiveIntervals

private ActiveSet createEmptySetOfActiveIntervals(IR ir)

determineSpillCostEstimator

private SpillCostEstimator determineSpillCostEstimator(IR ir)