com.oracle.graal.pointsto.flow

Class SourceTypeFlow

java.lang.Object

com.oracle.graal.pointsto.flow.TypeFlow<BytecodePosition>

com.oracle.graal.pointsto.flow.SourceTypeFlow

public final class SourceTypeFlow
extends TypeFlow<BytecodePosition>

Models a flow that *conditionally* introduces a type in the type flow graph only if it is marked as instantiated, e.g., by scanning a constant of that type or parsing an allocation bytecode. This flow is used for nodes that produce an object but don't register its type as instantiated themselves, e.g., like JavaReadNode or BytecodeExceptionNode. Also LoadHubNode, GetClassNode, LoadVMThreadLocalNode. The type state of this source is "empty" or "null" until the declared type is marked as instantiated, depending on the null state of the node stamp. When this flow is initialized it registers a callback with its declared type such that when the type is marked as instantiated it propagates the source state. If the declared type is already instantiated when the source flow is initialized then the callback is immediately triggered. If the type is really never instantiated, i.e., AnalysisType.isInstantiated() is still false at the end of the static analysis, then the callback is never triggered. That is correct, because in this case that type can never be produced by this flow (and the only possible value is null, if the stamp can be null, or empty).

Field Summary

Fields inherited from class com.oracle.graal.pointsto.flow.TypeFlow

declaredType, graphRef, id, inQueue, nextId, source, state

Constructor Summary

Constructors

Constructor and Description
SourceTypeFlow(BytecodePosition position, AnalysisType type, boolean canBeNull)
SourceTypeFlow(SourceTypeFlow original, MethodFlowsGraph methodFlows)

Method Summary

Modifier and Type	Method and Description
boolean	canSaturate() Can this type flow saturate? By default all type flows can saturate, with the exception of a few ones that need to track all their types, e.g., AllInstantiated, AllSynchronized, etc.
TypeFlow<BytecodePosition>	copy(PointsToAnalysis bb, MethodFlowsGraph methodFlows) By default a type flow is not cloneable.
void	initFlow(PointsToAnalysis bb) Initialization code for some type flow corner cases.
boolean	needsInitialization() Type flows that require initialization after the graph is created need to override this method and return true.
protected void	onInputSaturated(PointsToAnalysis bb, TypeFlow<?> input) Notified by an input that it is saturated and it will stop sending updates.
void	onObservedSaturated(PointsToAnalysis bb, TypeFlow<?> observed) Notified by an observed flow that it is saturated.
protected void	onSaturated(PointsToAnalysis bb) Called when this type flow becomes saturated.
String	toString()

Methods inherited from class com.oracle.graal.pointsto.flow.TypeFlow

addInput, addObservee, addObserver, addObserver, addState, addState, addUse, addUse, clearInputs, clearObservees, clearObservers, clearUses, declaredTypeFilter, declaredTypeFilter, doAddUse, equals, filter, filterUncheckedInterface, format, formatSource, getDeclaredType, getInputs, getObservees, getObservers, getSlot, getSource, getState, getUses, graphRef, hashCode, id, invalidate, isAllInstantiated, isClone, isContextInsensitive, isSaturated, isValid, method, notifyObserverOfSaturation, notifyUseOfSaturation, onObservedUpdate, onSaturated, receiver, removeObserver, removeUse, replacedObservedWith, replaceObservedWith, setObserved, setSaturated, setSlot, setState, swapAtObserver, swapAtUse, swapOut, update

Methods inherited from class java.lang.Object

clone, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

SourceTypeFlow

public SourceTypeFlow(BytecodePosition position,
                      AnalysisType type,
                      boolean canBeNull)

SourceTypeFlow

public SourceTypeFlow(SourceTypeFlow original,
                      MethodFlowsGraph methodFlows)

Method Detail

copy

public TypeFlow<BytecodePosition> copy(PointsToAnalysis bb,
                                       MethodFlowsGraph methodFlows)

Description copied from class: TypeFlow

By default a type flow is not cloneable.

Overrides:

copy in class TypeFlow<BytecodePosition>

initFlow

public void initFlow(PointsToAnalysis bb)

Description copied from class: TypeFlow

Initialization code for some type flow corner cases. TypeFlow.needsInitialization() also needs to be overridden to enable type flow initialization.

Overrides:

initFlow in class TypeFlow<BytecodePosition>

needsInitialization

public boolean needsInitialization()

Description copied from class: TypeFlow

Type flows that require initialization after the graph is created need to override this method and return true.

Overrides:

needsInitialization in class TypeFlow<BytecodePosition>

onObservedSaturated

public void onObservedSaturated(PointsToAnalysis bb,
                                TypeFlow<?> observed)

Description copied from class: TypeFlow

Notified by an observed flow that it is saturated.

Overrides:

onObservedSaturated in class TypeFlow<BytecodePosition>

onInputSaturated

protected void onInputSaturated(PointsToAnalysis bb,
                                TypeFlow<?> input)

Description copied from class: TypeFlow

Notified by an input that it is saturated and it will stop sending updates.

Overrides:

onInputSaturated in class TypeFlow<BytecodePosition>

onSaturated

protected void onSaturated(PointsToAnalysis bb)

Description copied from class: TypeFlow

Called when this type flow becomes saturated.

Overrides:

onSaturated in class TypeFlow<BytecodePosition>

canSaturate

public boolean canSaturate()

Description copied from class: TypeFlow

Can this type flow saturate? By default all type flows can saturate, with the exception of a few ones that need to track all their types, e.g., AllInstantiated, AllSynchronized, etc.

Overrides:

canSaturate in class TypeFlow<BytecodePosition>

toString

public String toString()

Overrides:

toString in class TypeFlow<BytecodePosition>