com.oracle.graal.compiler.common.type

Class AbstractObjectStamp

java.lang.Object

com.oracle.graal.compiler.common.type.Stamp

com.oracle.graal.compiler.common.type.AbstractPointerStamp

com.oracle.graal.compiler.common.type.AbstractObjectStamp

Direct Known Subclasses:

NarrowOopStamp, ObjectStamp

public abstract class AbstractObjectStamp
extends AbstractPointerStamp

Type describing all pointers to Java objects.

Field Summary

Fields

Modifier and Type	Field and Description
private boolean	exactType
private ResolvedJavaType	type

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractObjectStamp(ResolvedJavaType type, boolean exactType, boolean nonNull, boolean alwaysNull)

Method Summary

Modifier and Type	Method and Description
protected void	appendString(StringBuilder str)
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.
protected AbstractPointerStamp	copyWith(boolean newNonNull, boolean newAlwaysNull)
protected abstract AbstractObjectStamp	copyWith(ResolvedJavaType newType, boolean newExactType, boolean newNonNull, boolean newAlwaysNull)
Stamp	empty() Returns a stamp of the same kind, but with no allowed values.
boolean	equals(Object obj)
Kind	getStackKind() Gets a Java Kind that can be used to store a value of this stamp on the Java bytecode stack.
int	hashCode()
boolean	hasValues() Test whether this stamp has legal values.
Stamp	improveWith(Stamp other) Returns the stamp representing the type of this stamp after a cast to the type represented by the to stamp.
static boolean	isConcreteType(ResolvedJavaType type)
boolean	isExactType()
private static boolean	isInterfaceOrArrayOfInterface(ResolvedJavaType t)
ResolvedJavaType	javaType(MetaAccessProvider metaAccess) Returns the type of the stamp, guaranteed to be non-null.
Stamp	join(Stamp otherStamp) Returns the intersection of this stamp and the given stamp.
private Stamp	join0(Stamp otherStamp, boolean improve)
Stamp	meet(Stamp otherStamp) Returns the union of this stamp and the given stamp.
private static ResolvedJavaType	meetTypes(ResolvedJavaType a, ResolvedJavaType b)
ResolvedJavaType	type()
Stamp	unrestricted() Returns a stamp of the same kind, but allowing the full value range of the kind.

Methods inherited from class com.oracle.graal.compiler.common.type.AbstractPointerStamp

alwaysNull, asConstant, nonNull

Methods inherited from class com.oracle.graal.compiler.common.type.Stamp

alwaysDistinct, getLIRKind, isCompatible, isEmpty, neverDistinct, readConstant, tryImproveWith

Methods inherited from class java.lang.Object

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

Field Detail

type

private final ResolvedJavaType type

exactType

private final boolean exactType

Constructor Detail

AbstractObjectStamp

protected AbstractObjectStamp(ResolvedJavaType type,
                              boolean exactType,
                              boolean nonNull,
                              boolean alwaysNull)

Method Detail

copyWith

protected abstract AbstractObjectStamp copyWith(ResolvedJavaType newType,
                                                boolean newExactType,
                                                boolean newNonNull,
                                                boolean newAlwaysNull)

copyWith

protected final AbstractPointerStamp copyWith(boolean newNonNull,
                                              boolean newAlwaysNull)

Specified by:

copyWith in class AbstractPointerStamp

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.

Overrides:

unrestricted in class AbstractPointerStamp

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

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

hasValues

public boolean hasValues()

Description copied from class: Stamp

Test whether this stamp has legal values.

Specified by:

hasValues in class Stamp

getStackKind

public Kind getStackKind()

Description copied from class: Stamp

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

Overrides:

getStackKind in class AbstractPointerStamp

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

type

public ResolvedJavaType type()

isExactType

public boolean isExactType()

appendString

protected void appendString(StringBuilder str)

meet

public Stamp meet(Stamp otherStamp)

Description copied from class: Stamp

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

Overrides:

meet in class AbstractPointerStamp

Parameters:

otherStamp - The stamp that will enlarge this stamp.

Returns:

The union of this stamp and the given stamp.

join

public Stamp join(Stamp otherStamp)

Description copied from class: Stamp

Returns the intersection of this stamp and the given stamp.

Overrides:

join in class AbstractPointerStamp

Parameters:

otherStamp - The stamp that will tighten this stamp.

Returns:

The intersection of this stamp and the given stamp.

improveWith

public Stamp improveWith(Stamp other)

Returns the stamp representing the type of this stamp after a cast to the type represented by the to stamp. While this is very similar to a join(com.oracle.graal.compiler.common.type.Stamp) operation, in the case where both types are not obviously related, the cast operation will prefer the type of the to stamp. This is necessary as long as ObjectStamps are not able to accurately represent intersection types. For example when joining the RandomAccess type with the AbstractList type, without intersection types, this would result in the most generic type (Object ). For this reason, in some cases a castTo operation is preferable in order to keep at least the AbstractList type.

Overrides:

improveWith in class AbstractPointerStamp

Parameters:

other - the stamp this stamp should be casted to

Returns:

the new improved stamp or null if this stamp cannot be improved

join0

private Stamp join0(Stamp otherStamp,
                    boolean improve)

isInterfaceOrArrayOfInterface

private static boolean isInterfaceOrArrayOfInterface(ResolvedJavaType t)

isConcreteType

public static boolean isConcreteType(ResolvedJavaType type)

meetTypes

private static ResolvedJavaType meetTypes(ResolvedJavaType a,
                                          ResolvedJavaType b)

hashCode

public int hashCode()

Overrides:

hashCode in class AbstractPointerStamp

equals

public boolean equals(Object obj)

Overrides:

equals in class AbstractPointerStamp