com.oracle.truffle.api.frame

Class FrameDescriptor

java.lang.Object

com.oracle.truffle.api.frame.FrameDescriptor

All Implemented Interfaces:

Cloneable

public final class FrameDescriptor
extends Object
implements Cloneable

Descriptor of the slots of frame objects. Multiple frame instances are associated with one such descriptor.

Since:

0.8 or earlier

Constructor Summary

Constructors

Constructor and Description
FrameDescriptor() Constructs empty descriptor.
FrameDescriptor(Object defaultValue) Constructs new descriptor with specified FrameDescriptor.getDefaultValue().

Method Summary

Modifier and Type	Method and Description
FrameSlot	addFrameSlot(Object identifier) Adds frame slot.
FrameSlot	addFrameSlot(Object identifier, FrameSlotKind kind) Adds frame slot.
FrameSlot	addFrameSlot(Object identifier, Object info, FrameSlotKind kind) Adds new frame slot to FrameDescriptor.getSlots() list.
FrameDescriptor	copy() Deeper copy of the descriptor.
FrameSlot	findFrameSlot(Object identifier) Finds an existing slot.
FrameSlot	findOrAddFrameSlot(Object identifier) Finds an existing slot or creates new one.
FrameSlot	findOrAddFrameSlot(Object identifier, FrameSlotKind kind) Finds an existing slot or creates new one.
FrameSlot	findOrAddFrameSlot(Object identifier, Object info, FrameSlotKind kind) Finds an existing slot or creates new one.
Object	getDefaultValue() Default value for the created slots.
Set<Object>	getIdentifiers() Retrieve the list of all the identifiers associated with this frame descriptor.
Assumption	getNotInFrameAssumption(Object identifier) Make an assumption that no slot with the specified identifier is present in this frame descriptor.
int	getSize() Returns number of slots in the descriptor.
List<? extends FrameSlot>	getSlots() Current set of slots in the descriptor.
Assumption	getVersion() Returns an assumption reflecting the frame's current version, which is updated every time a slot is added or removed, or an existing slot's kind is changed.
void	removeFrameSlot(Object identifier) Removes a slot.
FrameDescriptor	shallowCopy() Shallow copy of the descriptor.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

FrameDescriptor

public FrameDescriptor()

Constructs empty descriptor. The FrameDescriptor.getDefaultValue() is null.

Since:

0.8 or earlier

FrameDescriptor

public FrameDescriptor(Object defaultValue)

Constructs new descriptor with specified FrameDescriptor.getDefaultValue().

Parameters:

defaultValue - to be returned from FrameDescriptor.getDefaultValue()

Since:

0.8 or earlier

Method Detail

addFrameSlot

public FrameSlot addFrameSlot(Object identifier)

Adds frame slot. Delegates to addFrameSlot(identifier, null, FrameSlotKind.Illegal). This is a slow operation that switches to interpreter mode.

Parameters:

identifier - key for the slot

Returns:

the newly created slot

Since:

0.8 or earlier

addFrameSlot

public FrameSlot addFrameSlot(Object identifier,
                              FrameSlotKind kind)

Adds frame slot. Delegates to addFrameSlot(identifier, null, kind). This is a slow operation that switches to interpreter mode.

Parameters:

identifier - key for the slot

kind - the kind of the new slot

Returns:

the newly created slot

Since:

0.8 or earlier

addFrameSlot

public FrameSlot addFrameSlot(Object identifier,
                              Object info,
                              FrameSlotKind kind)

Adds new frame slot to FrameDescriptor.getSlots() list. This is a slow operation that switches to interpreter mode.

Parameters:

identifier - key for the slot - it needs proper Object.equals(java.lang.Object) and Object.hashCode() implementations

info - additional information for the slot

kind - the kind of the new slot

Returns:

the newly created slot

Throws:

IllegalArgumentException - if a frame slot with the same identifier exists

Since:

0.8 or earlier

findFrameSlot

public FrameSlot findFrameSlot(Object identifier)

Finds an existing slot. This is a slow operation.

Parameters:

identifier - the key of the slot to search for

Returns:

the slot or null

Since:

0.8 or earlier

findOrAddFrameSlot

public FrameSlot findOrAddFrameSlot(Object identifier)

Finds an existing slot or creates new one. This is a slow operation.

Parameters:

identifier - the key of the slot to search for

Returns:

the slot

Since:

0.8 or earlier

findOrAddFrameSlot

public FrameSlot findOrAddFrameSlot(Object identifier,
                                    FrameSlotKind kind)

Finds an existing slot or creates new one. This is a slow operation.

Parameters:

identifier - the key of the slot to search for

kind - the kind for the newly created slot

Returns:

the found or newly created slot

Since:

0.8 or earlier

findOrAddFrameSlot

public FrameSlot findOrAddFrameSlot(Object identifier,
                                    Object info,
                                    FrameSlotKind kind)

Finds an existing slot or creates new one. This is a slow operation.

Parameters:

identifier - the key of the slot to search for

info - info for the newly created slot

kind - the kind for the newly created slot

Returns:

the found or newly created slot

Since:

0.8 or earlier

removeFrameSlot

public void removeFrameSlot(Object identifier)

Removes a slot. If the identifier is found, its slot is removed from this descriptor. This is a slow operation.

Parameters:

identifier - identifies the slot to remove

Throws:

IllegalArgumentException - if no such frame slot exists

Since:

0.8 or earlier

getSize

public int getSize()

Returns number of slots in the descriptor.

Returns:

the same value as FrameDescriptor.getSlots().List.size() would return

Since:

0.8 or earlier

getSlots

public List<? extends FrameSlot> getSlots()

Current set of slots in the descriptor.

Returns:

unmodifiable list of FrameSlot

Since:

0.8 or earlier

getIdentifiers

public Set<Object> getIdentifiers()

Retrieve the list of all the identifiers associated with this frame descriptor.

Returns:

the list of all the identifiers in this frame descriptor

Since:

0.8 or earlier

copy

public FrameDescriptor copy()

Deeper copy of the descriptor. Copies all slots in the descriptor, but only their identifier and info but not their kind!

Returns:

new instance of a descriptor with copies of values from this one

Since:

0.8 or earlier

shallowCopy

public FrameDescriptor shallowCopy()

Shallow copy of the descriptor. Re-uses the existing slots in new descriptor. As a result, if you change kind of one of the slots it is changed in the original as well as in the shallow copy.

Returns:

new instance of a descriptor with copies of values from this one

Since:

0.8 or earlier

getVersion

public Assumption getVersion()

Returns an assumption reflecting the frame's current version, which is updated every time a slot is added or removed, or an existing slot's kind is changed. This assumption is associated with compiled code that depends on the internal frame layout.

Returns:

an assumption invalidated when a slot is added or removed, or a slot kind changed.

Since:

0.8 or earlier

getDefaultValue

public Object getDefaultValue()

Default value for the created slots.

Returns:

value provided to FrameDescriptor.FrameDescriptor(java.lang.Object)

Since:

0.8 or earlier

getNotInFrameAssumption

public Assumption getNotInFrameAssumption(Object identifier)

Make an assumption that no slot with the specified identifier is present in this frame descriptor. Invalidated when a frame slot with the identifier is added.

Parameters:

identifier - frame slot identifier

Returns:

an assumption that this frame descriptor does not contain a slot with the identifier

Throws:

IllegalArgumentException - if the frame descriptor contains a slot with the identifier

Since:

0.8 or earlier

toString

public String toString()

Overrides:

toString in class Object

Since:

0.8 or earlier