org.graalvm.compiler.core.common.type

Class VoidStamp

java.lang.Object

org.graalvm.compiler.core.common.type.Stamp

org.graalvm.compiler.core.common.type.VoidStamp

All Implemented Interfaces:

SpeculationReasonGroup.SpeculationContextObject

public final class VoidStamp
extends Stamp

Singleton stamp representing the value of type void.

Nested Class Summary

Nested classes/interfaces inherited from interface org.graalvm.compiler.serviceprovider.SpeculationReasonGroup.SpeculationContextObject

SpeculationReasonGroup.SpeculationContextObject.Visitor

Method Summary

Modifier and Type	Method and Description
void	accept(SpeculationReasonGroup.SpeculationContextObject.Visitor v)
boolean	alwaysDistinct(Stamp other)
Stamp	constant(Constant c, MetaAccessProvider meta) If it is possible to represent single value stamps of this kind, this method returns the stamp representing the single value c.
Stamp	empty() Returns a stamp of the same kind, but with no allowed values.
LIRKind	getLIRKind(LIRKindTool tool) Gets a platform dependent LIRKind that can be used to store a value of this stamp.
JavaKind	getStackKind() Gets a Java JavaKind that can be used to store a value of this stamp on the Java bytecode stack.
boolean	hasValues() Test whether this stamp has legal values.
Stamp	improveWith(Stamp other) Tries to improve this stamp with the stamp given as parameter.
boolean	isCompatible(Constant constant) Check that the constant other is compatible with this stamp.
boolean	isCompatible(Stamp stamp) Check that the constant other is compatible with this stamp.
boolean	isUnrestricted() Tests whether this stamp represents all values of this kind.
ResolvedJavaType	javaType(MetaAccessProvider metaAccess) Returns the type of the stamp, guaranteed to be non-null.
Stamp	join(Stamp other) Returns the intersection of this stamp and the given stamp.
Stamp	meet(Stamp other) Returns the union of this stamp and the given stamp.
Constant	readConstant(MemoryAccessProvider provider, Constant base, long displacement) Read a value of this stamp from memory.
String	toString()
Stamp	unrestricted() Returns a stamp of the same kind, but allowing the full value range of the kind.

Methods inherited from class org.graalvm.compiler.core.common.type.Stamp

asConstant, isEmpty, isPointerStamp, makeSymbolic, neverDistinct, readConstant, tryImproveWith

Methods inherited from class java.lang.Object

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

Method Detail

accept

public void accept(SpeculationReasonGroup.SpeculationContextObject.Visitor v)

unrestricted

public Stamp unrestricted()

Description copied from class: Stamp

Returns a stamp of the same kind, but allowing the full value range of the kind. Stamp.unrestricted() is the neutral element of the Stamp.join(Stamp) operation.

Specified by:

unrestricted in class Stamp

isUnrestricted

public boolean isUnrestricted()

Description copied from class: Stamp

Tests whether this stamp represents all values of this kind.

Overrides:

isUnrestricted in class Stamp

getStackKind

public JavaKind getStackKind()

Description copied from class: Stamp

Gets a Java JavaKind that can be used to store a value of this stamp on the Java bytecode stack. Returns JavaKind.Illegal if a value of this stamp can not be stored on the bytecode stack.

Specified by:

getStackKind in class Stamp

improveWith

public Stamp improveWith(Stamp other)

Description copied from class: Stamp

Tries to improve this stamp with the stamp given as parameter. If successful, returns the new improved stamp. Otherwise, returns a stamp equal to this.

Specified by:

improveWith in class Stamp

Parameters:

other - the stamp that should be used to improve this stamp

Returns:

the newly improved stamp or a stamp equal to this if an improvement was not possible

getLIRKind

public LIRKind getLIRKind(LIRKindTool tool)

Description copied from class: Stamp

Gets a platform dependent LIRKind that can be used to store a value of this stamp.

Specified by:

getLIRKind in class Stamp

javaType

public ResolvedJavaType javaType(MetaAccessProvider metaAccess)

Description copied from class: Stamp

Returns the type of the stamp, guaranteed to be non-null. In some cases, this requires the lookup of class meta data, therefore the MetaAccessProvider is mandatory.

Specified by:

javaType in class Stamp

toString

public String toString()

Specified by:

toString in class Stamp

alwaysDistinct

public boolean alwaysDistinct(Stamp other)

Overrides:

alwaysDistinct in class Stamp

meet

public Stamp meet(Stamp other)

Description copied from class: Stamp

Returns the union of this stamp and the given stamp. Typically used to create stamps for phi nodes.

Specified by:

meet in class Stamp

Parameters:

other - The stamp that will enlarge this stamp.

Returns:

The union of this stamp and the given stamp.

join

public Stamp join(Stamp other)

Description copied from class: Stamp

Returns the intersection of this stamp and the given stamp.

Specified by:

join in class Stamp

Parameters:

other - The stamp that will tighten this stamp.

Returns:

The intersection of this stamp and the given stamp.

isCompatible

public boolean isCompatible(Stamp stamp)

Description copied from class: Stamp

Check that the constant other is compatible with this stamp.

Specified by:

isCompatible in class Stamp

isCompatible

public boolean isCompatible(Constant constant)

Description copied from class: Stamp

Check that the constant other is compatible with this stamp.

Specified by:

isCompatible in class Stamp

empty

public Stamp empty()

Description copied from class: Stamp

Returns a stamp of the same kind, but with no allowed values. Stamp.empty() is the neutral element of the Stamp.meet(Stamp) operation.

Specified by:

empty in class Stamp

hasValues

public boolean hasValues()

Description copied from class: Stamp

Test whether this stamp has legal values.

Specified by:

hasValues in class Stamp

readConstant

public Constant readConstant(MemoryAccessProvider provider,
                             Constant base,
                             long displacement)

Description copied from class: Stamp

Read a value of this stamp from memory.

Specified by:

readConstant in class Stamp

Returns:

the value read or null if the value can't be read for some reason.

constant

public Stamp constant(Constant c,
                      MetaAccessProvider meta)

Description copied from class: Stamp

If it is possible to represent single value stamps of this kind, this method returns the stamp representing the single value c. stamp.constant(c).asConstant() should be equal to c.

If it is not possible to represent single value stamps, this method returns a stamp that includes c, and is otherwise as narrow as possible.

Specified by:

constant in class Stamp