Class DynamicObject.SetShapeFlagsNode

java.lang.Object

com.oracle.truffle.api.nodes.Node

com.oracle.truffle.api.object.DynamicObject.SetShapeFlagsNode

All Implemented Interfaces:

NodeInterface, Cloneable

Enclosing class:

DynamicObject

public abstract static class DynamicObject.SetShapeFlagsNode
extends Node

Sets or updates language-specific object shape flags.

Since:

25.1

See Also:

• execute(DynamicObject, int)
• executeAdd(DynamicObject, int)
• executeRemove(DynamicObject, int)
• executeRemoveAndAdd(DynamicObject, int, int)

Nested Class Summary

Nested classes/interfaces inherited from class Node

Node.Child, Node.Children

Method Summary

Modifier and Type	Method	Description
static DynamicObject.SetShapeFlagsNode	create()
final boolean	execute(DynamicObject receiver, int newFlags)	Sets language-specific object shape flags, changing the object's shape if need be.
final boolean	executeAdd(DynamicObject receiver, int addedFlags)	Adds language-specific object shape flags, changing the object's shape if need be.
final boolean	executeRemove(DynamicObject receiver, int removedFlags)	Removes language-specific object shape flags, changing the object's shape if need be.
final boolean	executeRemoveAndAdd(DynamicObject receiver, int removedFlags, int addedFlags)	Removes, then adds language-specific object shape flags, changing the object's shape if need be.
static DynamicObject.SetShapeFlagsNode	getUncached()

Methods inherited from class Node

accept, adoptChildren, atomic, atomic, copy, deepCopy, getChildren, getCost, getDebugProperties, getDescription, getEncapsulatingSourceSection, getLock, getParent, getRootNode, getSourceSection, insert, insert, isAdoptable, isSafelyReplaceableBy, notifyInserted, onReplace, replace, replace, reportPolymorphicSpecialize, reportReplace, toString

Methods inherited from class Object

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

Method Details

execute

public final boolean execute(DynamicObject receiver,
 int newFlags)

Sets language-specific object shape flags, changing the object's shape if need be. These flags may be used to tag objects that possess characteristics that need to be queried efficiently on fast and slow paths. For example, they can be used to mark objects as frozen. Only the lowest 16 bits (i.e. values in the range 0 to 65535) are allowed, the remaining bits are currently reserved.

Usage example:

Implementing a freeze object operation:

abstract static class FreezeObjectNode extends Node {
    static final int FROZEN = 1;

    abstract void execute(DynamicObject receiver);

    @Specialization
    static void freeze(DynamicObject receiver,
                    @Cached DynamicObject.GetShapeFlagsNode getShapeFlagsNode,
                    @Cached DynamicObject.SetShapeFlagsNode setShapeFlagsNode) {
        int oldFlags = getShapeFlagsNode.execute(receiver);
        int newFlags = oldFlags | FROZEN;
        if (newFlags != oldFlags) {
            setShapeFlagsNode.execute(receiver, newFlags);
        }
    }
}

Note that executeAdd(DynamicObject, int) is more efficient and convenient for that particular pattern.

Parameters:

newFlags - the flags to set; must be in the range from 0 to 65535 (inclusive).

Returns:

true if the object's shape changed, false if no change was made.

Throws:

IllegalArgumentException - if the flags are not in the allowed range.

Since:

25.1

See Also:

• DynamicObject.GetShapeFlagsNode
• executeAdd(DynamicObject, int)
• Shape.Builder.shapeFlags(int)

executeAdd

public final boolean executeAdd(DynamicObject receiver,
 int addedFlags)

Adds language-specific object shape flags, changing the object's shape if need be.

Usage example:

Implementing a freeze object operation:

abstract static class FreezeNode extends Node {
    static final int FROZEN = 1;

    abstract void execute(DynamicObject receiver);

    @Specialization
    static void freeze(DynamicObject receiver,
                    @Cached DynamicObject.SetShapeFlagsNode setShapeFlagsNode) {
        setShapeFlagsNode.executeAdd(receiver, FROZEN);
    }
}

Since:

25.1

See Also:

• execute(DynamicObject, int)

executeRemove

public final boolean executeRemove(DynamicObject receiver,
 int removedFlags)

Removes language-specific object shape flags, changing the object's shape if need be.

Since:

25.1

See Also:

• execute(DynamicObject, int)

executeRemoveAndAdd

public final boolean executeRemoveAndAdd(DynamicObject receiver,
 int removedFlags,
 int addedFlags)

Removes, then adds language-specific object shape flags, changing the object's shape if need be.

Since:

25.1

See Also:

• execute(DynamicObject, int)

create

public static DynamicObject.SetShapeFlagsNode create()

Since:

25.1

getUncached

public static DynamicObject.SetShapeFlagsNode getUncached()

Since:

25.1