org.jikesrvm.compilers.opt

Class FieldAnalysis

java.lang.Object

org.jikesrvm.compilers.opt.driver.CompilerPhase

org.jikesrvm.compilers.opt.FieldAnalysis

public final class FieldAnalysis
extends CompilerPhase

Flow-insensitive, context-insensitive, interprocedural analysis of fields.

• TODO: handle more than just private fields
• TODO: make this re-entrant
• TODO: better class hierarchy analysis
• TODO: context-sensitive or flow-sensitive summaries.
• TODO: force eager analysis of methods

Field Summary

Fields

Modifier and Type	Field and Description
private static FieldDatabase	db The backing store
private static boolean	DEBUG

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

container

Constructor Summary

Constructors

Constructor and Description
FieldAnalysis()

Method Summary

Modifier and Type	Method and Description
static TypeReference	getConcreteType(RVMField f) Gets the a single concrete type for a field, if there is one.
String	getName()
private static boolean	isCandidate(TypeReference tref) Is a type a candidate for type analysis?
private static boolean	isTrouble(RVMField f) For some special classes, the flow-insensitive summaries are INCORRECT due to using the wrong implementation during boot image writing.
CompilerPhase	newExecution(IR ir) Return this instance of this phase.
void	perform(IR ir) Record field analysis information for an IR.
private static void	recordBottom(RVMMethod m, RVMField f) Records that a method writes an unknown concrete type to a field.
private static void	recordConcreteType(RVMMethod m, RVMField f, TypeReference t) Record that a method stores an object of a particular concrete type to a field.
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, getClassConstructor, getCompilerPhaseConstructor, getCompilerPhaseConstructor, performPhase, printingEnabled, reportAdditionalStats, setContainer, verify

Methods inherited from class java.lang.Object

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

Field Detail

DEBUG

private static final boolean DEBUG

See Also:

Constant Field Values

db

private static final FieldDatabase db

The backing store

Constructor Detail

FieldAnalysis

public FieldAnalysis()

Method Detail

newExecution

public CompilerPhase newExecution(IR ir)

Return this instance of this phase. This phase contains no per-compilation instance fields.

Overrides:

newExecution in class CompilerPhase

Parameters:

ir - not used

Returns:

this

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 if the phase should be performed

getName

public String getName()

Specified by:

getName in class CompilerPhase

Returns:

a String which is the name of the phase.

isCandidate

private static boolean isCandidate(TypeReference tref)

Is a type a candidate for type analysis?

NO iff:

• it's a primitive
• it's final
• it's an array of primitive
• it's an array of final

Parameters:

tref - the type

Returns:

true if the type is a candidate for type analysis, i.e. if it's a non-final reference type

getConcreteType

public static TypeReference getConcreteType(RVMField f)

Gets the a single concrete type for a field, if there is one.

Parameters:

f - the field that's of interest

Returns:

the concrete type of a field if available, null otherwise

perform

public void perform(IR ir)

Record field analysis information for an IR.

Specified by:

perform in class CompilerPhase

Parameters:

ir - the governing IR

recordBottom

private static void recordBottom(RVMMethod m,
                                 RVMField f)

Records that a method writes an unknown concrete type to a field.

Parameters:

m - the writing method

f - the written field

recordConcreteType

private static void recordConcreteType(RVMMethod m,
                                       RVMField f,
                                       TypeReference t)

Record that a method stores an object of a particular concrete type to a field.

Parameters:

m - the writing method

f - the written field

t - the concrete type

isTrouble

private static boolean isTrouble(RVMField f)

For some special classes, the flow-insensitive summaries are INCORRECT due to using the wrong implementation during boot image writing. For these special cases, give up. TODO: work around this by recomputing the summary at runtime?

Parameters:

f - the field to check

Returns:

true if the field information may be incorrect