Java Code Examples for jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor#isOptimistic()
The following examples show how to use
jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor#isOptimistic() .
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Example 1
| Source File: ContinuousArrayData.java From TencentKona-8 with GNU General Public License v2.0 | 6 votes |
|
/**
* Return a fast linked array getter, or null if we have to dispatch to super class
* @param desc descriptor
* @param request link request
* @return invocation or null if needs to be sent to slow relink
*/
@Override
public GuardedInvocation findFastGetIndexMethod(final Class<? extends ArrayData> clazz, final CallSiteDescriptor desc, final LinkRequest request) {
final MethodType callType = desc.getMethodType();
final Class<?> indexType = callType.parameterType(1);
final Class<?> returnType = callType.returnType();
if (ContinuousArrayData.class.isAssignableFrom(clazz) && indexType == int.class) {
final Object[] args = request.getArguments();
final int index = (int)args[args.length - 1];
if (has(index)) {
final MethodHandle getArray = ScriptObject.GET_ARRAY.methodHandle();
final int programPoint = NashornCallSiteDescriptor.isOptimistic(desc) ? NashornCallSiteDescriptor.getProgramPoint(desc) : INVALID_PROGRAM_POINT;
MethodHandle getElement = getElementGetter(returnType, programPoint);
if (getElement != null) {
getElement = MH.filterArguments(getElement, 0, MH.asType(getArray, getArray.type().changeReturnType(clazz)));
final MethodHandle guard = MH.insertArguments(FAST_ACCESS_GUARD, 0, clazz);
return new GuardedInvocation(getElement, guard, (SwitchPoint)null, ClassCastException.class);
}
}
}
return null;
}
Example 2
| Source File: ContinuousArrayData.java From openjdk-jdk9 with GNU General Public License v2.0 | 6 votes |
|
/**
* Return a fast linked array getter, or null if we have to dispatch to super class
* @param desc descriptor
* @param request link request
* @return invocation or null if needs to be sent to slow relink
*/
@Override
public GuardedInvocation findFastGetIndexMethod(final Class<? extends ArrayData> clazz, final CallSiteDescriptor desc, final LinkRequest request) {
final MethodType callType = desc.getMethodType();
final Class<?> indexType = callType.parameterType(1);
final Class<?> returnType = callType.returnType();
if (ContinuousArrayData.class.isAssignableFrom(clazz) && indexType == int.class) {
final Object[] args = request.getArguments();
final int index = (int)args[args.length - 1];
if (has(index)) {
final MethodHandle getArray = ScriptObject.GET_ARRAY.methodHandle();
final int programPoint = NashornCallSiteDescriptor.isOptimistic(desc) ? NashornCallSiteDescriptor.getProgramPoint(desc) : INVALID_PROGRAM_POINT;
MethodHandle getElement = getElementGetter(returnType, programPoint);
if (getElement != null) {
getElement = MH.filterArguments(getElement, 0, MH.asType(getArray, getArray.type().changeReturnType(clazz)));
final MethodHandle guard = MH.insertArguments(FAST_ACCESS_GUARD, 0, clazz);
return new GuardedInvocation(getElement, guard, (SwitchPoint)null, ClassCastException.class);
}
}
}
return null;
}
Example 3
| Source File: ContinuousArrayData.java From hottub with GNU General Public License v2.0 | 6 votes |
|
/**
* Return a fast linked array getter, or null if we have to dispatch to super class
* @param desc descriptor
* @param request link request
* @return invocation or null if needs to be sent to slow relink
*/
@Override
public GuardedInvocation findFastGetIndexMethod(final Class<? extends ArrayData> clazz, final CallSiteDescriptor desc, final LinkRequest request) {
final MethodType callType = desc.getMethodType();
final Class<?> indexType = callType.parameterType(1);
final Class<?> returnType = callType.returnType();
if (ContinuousArrayData.class.isAssignableFrom(clazz) && indexType == int.class) {
final Object[] args = request.getArguments();
final int index = (int)args[args.length - 1];
if (has(index)) {
final MethodHandle getArray = ScriptObject.GET_ARRAY.methodHandle();
final int programPoint = NashornCallSiteDescriptor.isOptimistic(desc) ? NashornCallSiteDescriptor.getProgramPoint(desc) : INVALID_PROGRAM_POINT;
MethodHandle getElement = getElementGetter(returnType, programPoint);
if (getElement != null) {
getElement = MH.filterArguments(getElement, 0, MH.asType(getArray, getArray.type().changeReturnType(clazz)));
final MethodHandle guard = MH.insertArguments(FAST_ACCESS_GUARD, 0, clazz);
return new GuardedInvocation(getElement, guard, (SwitchPoint)null, ClassCastException.class);
}
}
}
return null;
}
Example 4
| Source File: ScriptObject.java From openjdk-jdk8u with GNU General Public License v2.0 | 5 votes |
|
private GuardedInvocation createEmptyGetter(final CallSiteDescriptor desc, final boolean explicitInstanceOfCheck, final String name) {
if (NashornCallSiteDescriptor.isOptimistic(desc)) {
throw new UnwarrantedOptimismException(UNDEFINED, NashornCallSiteDescriptor.getProgramPoint(desc), Type.OBJECT);
}
return new GuardedInvocation(Lookup.emptyGetter(desc.getMethodType().returnType()),
NashornGuards.getMapGuard(getMap(), explicitInstanceOfCheck), getProtoSwitchPoints(name, null),
explicitInstanceOfCheck ? null : ClassCastException.class);
}
Example 5
| Source File: ScriptObject.java From openjdk-jdk9 with GNU General Public License v2.0 | 5 votes |
|
private GuardedInvocation createEmptyGetter(final CallSiteDescriptor desc, final boolean explicitInstanceOfCheck, final String name) {
if (NashornCallSiteDescriptor.isOptimistic(desc)) {
throw new UnwarrantedOptimismException(UNDEFINED, NashornCallSiteDescriptor.getProgramPoint(desc), Type.OBJECT);
}
return new GuardedInvocation(Lookup.emptyGetter(desc.getMethodType().returnType()),
NashornGuards.getMapGuard(getMap(), explicitInstanceOfCheck), getProtoSwitchPoints(name, null),
explicitInstanceOfCheck ? null : ClassCastException.class);
}
Example 6
| Source File: OptimisticReturnFilters.java From TencentKona-8 with GNU General Public License v2.0 | 5 votes |
|
/**
* Given a guarded invocation and a callsite descriptor, perform return value filtering
* according to the optimistic type coercion rules, using the return value from the descriptor
* @param inv the invocation
* @param desc the descriptor
* @return filtered invocation
*/
public static GuardedInvocation filterOptimisticReturnValue(final GuardedInvocation inv, final CallSiteDescriptor desc) {
if(!NashornCallSiteDescriptor.isOptimistic(desc)) {
return inv;
}
return inv.replaceMethods(filterOptimisticReturnValue(inv.getInvocation(), desc.getMethodType().returnType(),
NashornCallSiteDescriptor.getProgramPoint(desc)), inv.getGuard());
}
Example 7
| Source File: OptimisticReturnFilters.java From openjdk-jdk9 with GNU General Public License v2.0 | 5 votes |
|
/**
* Given a guarded invocation and a callsite descriptor, perform return value filtering
* according to the optimistic type coercion rules, using the return value from the descriptor
* @param inv the invocation
* @param desc the descriptor
* @return filtered invocation
*/
public static GuardedInvocation filterOptimisticReturnValue(final GuardedInvocation inv, final CallSiteDescriptor desc) {
if(!NashornCallSiteDescriptor.isOptimistic(desc)) {
return inv;
}
return inv.replaceMethods(filterOptimisticReturnValue(inv.getInvocation(), desc.getMethodType().returnType(),
NashornCallSiteDescriptor.getProgramPoint(desc)), inv.getGuard());
}
Example 8
| Source File: ScriptObject.java From openjdk-jdk8u-backup with GNU General Public License v2.0 | 5 votes |
|
private GuardedInvocation createEmptyGetter(final CallSiteDescriptor desc, final boolean explicitInstanceOfCheck, final String name) {
if (NashornCallSiteDescriptor.isOptimistic(desc)) {
throw new UnwarrantedOptimismException(UNDEFINED, NashornCallSiteDescriptor.getProgramPoint(desc), Type.OBJECT);
}
return new GuardedInvocation(Lookup.emptyGetter(desc.getMethodType().returnType()),
NashornGuards.getMapGuard(getMap(), explicitInstanceOfCheck), getProtoSwitchPoints(name, null),
explicitInstanceOfCheck ? null : ClassCastException.class);
}
Example 9
| Source File: OptimisticReturnFilters.java From jdk8u_nashorn with GNU General Public License v2.0 | 5 votes |
|
/**
* Given a guarded invocation and a callsite descriptor, perform return value filtering
* according to the optimistic type coercion rules, using the return value from the descriptor
* @param inv the invocation
* @param desc the descriptor
* @return filtered invocation
*/
public static GuardedInvocation filterOptimisticReturnValue(final GuardedInvocation inv, final CallSiteDescriptor desc) {
if(!NashornCallSiteDescriptor.isOptimistic(desc)) {
return inv;
}
return inv.replaceMethods(filterOptimisticReturnValue(inv.getInvocation(), desc.getMethodType().returnType(),
NashornCallSiteDescriptor.getProgramPoint(desc)), inv.getGuard());
}
Example 10
| Source File: OptimisticReturnFilters.java From openjdk-jdk8u-backup with GNU General Public License v2.0 | 5 votes |
|
/**
* Given a guarded invocation and a callsite descriptor, perform return value filtering
* according to the optimistic type coercion rules, using the return value from the descriptor
* @param inv the invocation
* @param desc the descriptor
* @return filtered invocation
*/
public static GuardedInvocation filterOptimisticReturnValue(final GuardedInvocation inv, final CallSiteDescriptor desc) {
if(!NashornCallSiteDescriptor.isOptimistic(desc)) {
return inv;
}
return inv.replaceMethods(filterOptimisticReturnValue(inv.getInvocation(), desc.getMethodType().returnType(),
NashornCallSiteDescriptor.getProgramPoint(desc)), inv.getGuard());
}
Example 11
| Source File: ScriptObject.java From TencentKona-8 with GNU General Public License v2.0 | 5 votes |
|
private GuardedInvocation createEmptyGetter(final CallSiteDescriptor desc, final boolean explicitInstanceOfCheck, final String name) {
if (NashornCallSiteDescriptor.isOptimistic(desc)) {
throw new UnwarrantedOptimismException(UNDEFINED, NashornCallSiteDescriptor.getProgramPoint(desc), Type.OBJECT);
}
return new GuardedInvocation(Lookup.emptyGetter(desc.getMethodType().returnType()),
NashornGuards.getMapGuard(getMap(), explicitInstanceOfCheck), getProtoSwitchPoints(name, null),
explicitInstanceOfCheck ? null : ClassCastException.class);
}
Example 12
| Source File: OptimisticReturnFilters.java From openjdk-jdk8u with GNU General Public License v2.0 | 5 votes |
|
/**
* Given a guarded invocation and a callsite descriptor, perform return value filtering
* according to the optimistic type coercion rules, using the return value from the descriptor
* @param inv the invocation
* @param desc the descriptor
* @return filtered invocation
*/
public static GuardedInvocation filterOptimisticReturnValue(final GuardedInvocation inv, final CallSiteDescriptor desc) {
if(!NashornCallSiteDescriptor.isOptimistic(desc)) {
return inv;
}
return inv.replaceMethods(filterOptimisticReturnValue(inv.getInvocation(), desc.getMethodType().returnType(),
NashornCallSiteDescriptor.getProgramPoint(desc)), inv.getGuard());
}
Example 13
| Source File: ScriptObject.java From jdk8u60 with GNU General Public License v2.0 | 5 votes |
|
private GuardedInvocation createEmptyGetter(final CallSiteDescriptor desc, final boolean explicitInstanceOfCheck, final String name) {
if (NashornCallSiteDescriptor.isOptimistic(desc)) {
throw new UnwarrantedOptimismException(UNDEFINED, NashornCallSiteDescriptor.getProgramPoint(desc), Type.OBJECT);
}
return new GuardedInvocation(Lookup.emptyGetter(desc.getMethodType().returnType()),
NashornGuards.getMapGuard(getMap(), explicitInstanceOfCheck), getProtoSwitchPoint(name, null),
explicitInstanceOfCheck ? null : ClassCastException.class);
}
Example 14
| Source File: ScriptObject.java From hottub with GNU General Public License v2.0 | 5 votes |
|
private GuardedInvocation createEmptyGetter(final CallSiteDescriptor desc, final boolean explicitInstanceOfCheck, final String name) {
if (NashornCallSiteDescriptor.isOptimistic(desc)) {
throw new UnwarrantedOptimismException(UNDEFINED, NashornCallSiteDescriptor.getProgramPoint(desc), Type.OBJECT);
}
return new GuardedInvocation(Lookup.emptyGetter(desc.getMethodType().returnType()),
NashornGuards.getMapGuard(getMap(), explicitInstanceOfCheck), getProtoSwitchPoints(name, null),
explicitInstanceOfCheck ? null : ClassCastException.class);
}
Example 15
| Source File: ScriptObject.java From jdk8u_nashorn with GNU General Public License v2.0 | 5 votes |
|
private GuardedInvocation createEmptyGetter(final CallSiteDescriptor desc, final boolean explicitInstanceOfCheck, final String name) {
if (NashornCallSiteDescriptor.isOptimistic(desc)) {
throw new UnwarrantedOptimismException(UNDEFINED, NashornCallSiteDescriptor.getProgramPoint(desc), Type.OBJECT);
}
return new GuardedInvocation(Lookup.emptyGetter(desc.getMethodType().returnType()),
NashornGuards.getMapGuard(getMap(), explicitInstanceOfCheck), getProtoSwitchPoints(name, null),
explicitInstanceOfCheck ? null : ClassCastException.class);
}
Example 16
| Source File: GlobalConstants.java From TencentKona-8 with GNU General Public License v2.0 | 4 votes |
|
/**
* Try to turn a getter into a MethodHandle.constant, if possible
*
* @param find property lookup
* @param receiver receiver
* @param desc callsite descriptor
*
* @return resulting getter, or null if failed to create constant
*/
GuardedInvocation findGetMethod(final FindProperty find, final ScriptObject receiver, final CallSiteDescriptor desc) {
// Only use constant getter for fast scope access, because the receiver may change between invocations
// for slow-scope and non-scope callsites.
// Also return null for user accessor properties as they may have side effects.
if (invalidatedForever.get() || !NashornCallSiteDescriptor.isFastScope(desc)
|| (GLOBAL_ONLY && !find.getOwner().isGlobal())
|| find.getProperty() instanceof UserAccessorProperty) {
return null;
}
final boolean isOptimistic = NashornCallSiteDescriptor.isOptimistic(desc);
final int programPoint = isOptimistic ? getProgramPoint(desc) : INVALID_PROGRAM_POINT;
final Class<?> retType = desc.getMethodType().returnType();
final String name = desc.getNameToken(CallSiteDescriptor.NAME_OPERAND);
synchronized (this) {
final Access acc = getOrCreateSwitchPoint(name);
log.fine("Starting to look up object value " + name);
final Object c = find.getObjectValue();
if (log.isEnabled()) {
log.fine("Trying to link constant GETTER " + acc + " value = " + c);
}
if (acc.hasBeenInvalidated() || acc.guardFailed() || invalidatedForever.get()) {
if (log.isEnabled()) {
log.info("*** GET: Giving up on " + quote(name) + " - retry count has exceeded " + DynamicLinker.getLinkedCallSiteLocation());
}
return null;
}
final MethodHandle cmh = constantGetter(c);
MethodHandle mh;
MethodHandle guard;
if (isOptimistic) {
if (JSType.getAccessorTypeIndex(cmh.type().returnType()) <= JSType.getAccessorTypeIndex(retType)) {
//widen return type - this is pessimistic, so it will always work
mh = MH.asType(cmh, cmh.type().changeReturnType(retType));
} else {
//immediately invalidate - we asked for a too wide constant as a narrower one
mh = MH.dropArguments(MH.insertArguments(JSType.THROW_UNWARRANTED.methodHandle(), 0, c, programPoint), 0, Object.class);
}
} else {
//pessimistic return type filter
mh = Lookup.filterReturnType(cmh, retType);
}
if (find.getOwner().isGlobal()) {
guard = null;
} else {
guard = MH.insertArguments(RECEIVER_GUARD, 0, acc, receiver);
}
if (log.isEnabled()) {
log.info("Linked getter " + quote(name) + " as MethodHandle.constant() -> " + c + " " + acc.getSwitchPoint());
mh = MethodHandleFactory.addDebugPrintout(log, Level.FINE, mh, "get const " + acc);
}
return new GuardedInvocation(mh, guard, acc.getSwitchPoint(), null);
}
}
Example 17
| Source File: GlobalConstants.java From hottub with GNU General Public License v2.0 | 4 votes |
|
/**
* Try to turn a getter into a MethodHandle.constant, if possible
*
* @param find property lookup
* @param receiver receiver
* @param desc callsite descriptor
*
* @return resulting getter, or null if failed to create constant
*/
GuardedInvocation findGetMethod(final FindProperty find, final ScriptObject receiver, final CallSiteDescriptor desc) {
// Only use constant getter for fast scope access, because the receiver may change between invocations
// for slow-scope and non-scope callsites.
// Also return null for user accessor properties as they may have side effects.
if (invalidatedForever.get() || !NashornCallSiteDescriptor.isFastScope(desc)
|| (GLOBAL_ONLY && !find.getOwner().isGlobal())
|| find.getProperty() instanceof UserAccessorProperty) {
return null;
}
final boolean isOptimistic = NashornCallSiteDescriptor.isOptimistic(desc);
final int programPoint = isOptimistic ? getProgramPoint(desc) : INVALID_PROGRAM_POINT;
final Class<?> retType = desc.getMethodType().returnType();
final String name = desc.getNameToken(CallSiteDescriptor.NAME_OPERAND);
synchronized (this) {
final Access acc = getOrCreateSwitchPoint(name);
log.fine("Starting to look up object value " + name);
final Object c = find.getObjectValue();
if (log.isEnabled()) {
log.fine("Trying to link constant GETTER " + acc + " value = " + c);
}
if (acc.hasBeenInvalidated() || acc.guardFailed() || invalidatedForever.get()) {
if (log.isEnabled()) {
log.info("*** GET: Giving up on " + quote(name) + " - retry count has exceeded " + DynamicLinker.getLinkedCallSiteLocation());
}
return null;
}
final MethodHandle cmh = constantGetter(c);
MethodHandle mh;
MethodHandle guard;
if (isOptimistic) {
if (JSType.getAccessorTypeIndex(cmh.type().returnType()) <= JSType.getAccessorTypeIndex(retType)) {
//widen return type - this is pessimistic, so it will always work
mh = MH.asType(cmh, cmh.type().changeReturnType(retType));
} else {
//immediately invalidate - we asked for a too wide constant as a narrower one
mh = MH.dropArguments(MH.insertArguments(JSType.THROW_UNWARRANTED.methodHandle(), 0, c, programPoint), 0, Object.class);
}
} else {
//pessimistic return type filter
mh = Lookup.filterReturnType(cmh, retType);
}
if (find.getOwner().isGlobal()) {
guard = null;
} else {
guard = MH.insertArguments(RECEIVER_GUARD, 0, acc, receiver);
}
if (log.isEnabled()) {
log.info("Linked getter " + quote(name) + " as MethodHandle.constant() -> " + c + " " + acc.getSwitchPoint());
mh = MethodHandleFactory.addDebugPrintout(log, Level.FINE, mh, "get const " + acc);
}
return new GuardedInvocation(mh, guard, acc.getSwitchPoint(), null);
}
}
Example 18
| Source File: GlobalConstants.java From jdk8u_nashorn with GNU General Public License v2.0 | 4 votes |
|
/**
* Try to turn a getter into a MethodHandle.constant, if possible
*
* @param find property lookup
* @param receiver receiver
* @param desc callsite descriptor
*
* @return resulting getter, or null if failed to create constant
*/
GuardedInvocation findGetMethod(final FindProperty find, final ScriptObject receiver, final CallSiteDescriptor desc) {
// Only use constant getter for fast scope access, because the receiver may change between invocations
// for slow-scope and non-scope callsites.
// Also return null for user accessor properties as they may have side effects.
if (invalidatedForever.get() || !NashornCallSiteDescriptor.isFastScope(desc)
|| (GLOBAL_ONLY && !find.getOwner().isGlobal())
|| find.getProperty() instanceof UserAccessorProperty) {
return null;
}
final boolean isOptimistic = NashornCallSiteDescriptor.isOptimistic(desc);
final int programPoint = isOptimistic ? getProgramPoint(desc) : INVALID_PROGRAM_POINT;
final Class<?> retType = desc.getMethodType().returnType();
final String name = desc.getNameToken(CallSiteDescriptor.NAME_OPERAND);
synchronized (this) {
final Access acc = getOrCreateSwitchPoint(name);
log.fine("Starting to look up object value " + name);
final Object c = find.getObjectValue();
if (log.isEnabled()) {
log.fine("Trying to link constant GETTER " + acc + " value = " + c);
}
if (acc.hasBeenInvalidated() || acc.guardFailed() || invalidatedForever.get()) {
if (log.isEnabled()) {
log.info("*** GET: Giving up on " + quote(name) + " - retry count has exceeded " + DynamicLinker.getLinkedCallSiteLocation());
}
return null;
}
final MethodHandle cmh = constantGetter(c);
MethodHandle mh;
MethodHandle guard;
if (isOptimistic) {
if (JSType.getAccessorTypeIndex(cmh.type().returnType()) <= JSType.getAccessorTypeIndex(retType)) {
//widen return type - this is pessimistic, so it will always work
mh = MH.asType(cmh, cmh.type().changeReturnType(retType));
} else {
//immediately invalidate - we asked for a too wide constant as a narrower one
mh = MH.dropArguments(MH.insertArguments(JSType.THROW_UNWARRANTED.methodHandle(), 0, c, programPoint), 0, Object.class);
}
} else {
//pessimistic return type filter
mh = Lookup.filterReturnType(cmh, retType);
}
if (find.getOwner().isGlobal()) {
guard = null;
} else {
guard = MH.insertArguments(RECEIVER_GUARD, 0, acc, receiver);
}
if (log.isEnabled()) {
log.info("Linked getter " + quote(name) + " as MethodHandle.constant() -> " + c + " " + acc.getSwitchPoint());
mh = MethodHandleFactory.addDebugPrintout(log, Level.FINE, mh, "get const " + acc);
}
return new GuardedInvocation(mh, guard, acc.getSwitchPoint(), null);
}
}
Example 19
| Source File: GlobalConstants.java From jdk8u60 with GNU General Public License v2.0 | 4 votes |
|
/**
* Try to turn a getter into a MethodHandle.constant, if possible
*
* @param find property lookup
* @param receiver receiver
* @param desc callsite descriptor
*
* @return resulting getter, or null if failed to create constant
*/
GuardedInvocation findGetMethod(final FindProperty find, final ScriptObject receiver, final CallSiteDescriptor desc) {
// Only use constant getter for fast scope access, because the receiver may change between invocations
// for slow-scope and non-scope callsites.
// Also return null for user accessor properties as they may have side effects.
if (invalidatedForever.get() || !NashornCallSiteDescriptor.isFastScope(desc)
|| (GLOBAL_ONLY && !find.getOwner().isGlobal())
|| find.getProperty() instanceof UserAccessorProperty) {
return null;
}
final boolean isOptimistic = NashornCallSiteDescriptor.isOptimistic(desc);
final int programPoint = isOptimistic ? getProgramPoint(desc) : INVALID_PROGRAM_POINT;
final Class<?> retType = desc.getMethodType().returnType();
final String name = desc.getNameToken(CallSiteDescriptor.NAME_OPERAND);
synchronized (this) {
final Access acc = getOrCreateSwitchPoint(name);
log.fine("Starting to look up object value " + name);
final Object c = find.getObjectValue();
if (log.isEnabled()) {
log.fine("Trying to link constant GETTER " + acc + " value = " + c);
}
if (acc.hasBeenInvalidated() || acc.guardFailed() || invalidatedForever.get()) {
if (log.isEnabled()) {
log.info("*** GET: Giving up on " + quote(name) + " - retry count has exceeded " + DynamicLinker.getLinkedCallSiteLocation());
}
return null;
}
final MethodHandle cmh = constantGetter(c);
MethodHandle mh;
MethodHandle guard;
if (isOptimistic) {
if (JSType.getAccessorTypeIndex(cmh.type().returnType()) <= JSType.getAccessorTypeIndex(retType)) {
//widen return type - this is pessimistic, so it will always work
mh = MH.asType(cmh, cmh.type().changeReturnType(retType));
} else {
//immediately invalidate - we asked for a too wide constant as a narrower one
mh = MH.dropArguments(MH.insertArguments(JSType.THROW_UNWARRANTED.methodHandle(), 0, c, programPoint), 0, Object.class);
}
} else {
//pessimistic return type filter
mh = Lookup.filterReturnType(cmh, retType);
}
if (find.getOwner().isGlobal()) {
guard = null;
} else {
guard = MH.insertArguments(RECEIVER_GUARD, 0, acc, receiver);
}
if (log.isEnabled()) {
log.info("Linked getter " + quote(name) + " as MethodHandle.constant() -> " + c + " " + acc.getSwitchPoint());
mh = MethodHandleFactory.addDebugPrintout(log, Level.FINE, mh, "get const " + acc);
}
return new GuardedInvocation(mh, guard, acc.getSwitchPoint(), null);
}
}
Example 20
| Source File: GlobalConstants.java From openjdk-jdk9 with GNU General Public License v2.0 | 4 votes |
|
/**
* Try to turn a getter into a MethodHandle.constant, if possible
*
* @param find property lookup
* @param receiver receiver
* @param desc callsite descriptor
*
* @return resulting getter, or null if failed to create constant
*/
GuardedInvocation findGetMethod(final FindProperty find, final ScriptObject receiver, final CallSiteDescriptor desc) {
// Only use constant getter for fast scope access, because the receiver may change between invocations
// for slow-scope and non-scope callsites.
// Also return null for user accessor properties as they may have side effects.
if (invalidatedForever.get() || !NashornCallSiteDescriptor.isFastScope(desc)
|| (GLOBAL_ONLY && !find.getOwner().isGlobal())
|| find.getProperty() instanceof UserAccessorProperty) {
return null;
}
final boolean isOptimistic = NashornCallSiteDescriptor.isOptimistic(desc);
final int programPoint = isOptimistic ? getProgramPoint(desc) : INVALID_PROGRAM_POINT;
final Class<?> retType = desc.getMethodType().returnType();
final String name = NashornCallSiteDescriptor.getOperand(desc);
synchronized (this) {
final Access acc = getOrCreateSwitchPoint(name);
log.fine("Starting to look up object value " + name);
final Object c = find.getObjectValue();
if (log.isEnabled()) {
log.fine("Trying to link constant GETTER " + acc + " value = " + c);
}
if (acc.hasBeenInvalidated() || acc.guardFailed() || invalidatedForever.get()) {
if (log.isEnabled()) {
log.info("*** GET: Giving up on " + quote(name) + " - retry count has exceeded " + DynamicLinker.getLinkedCallSiteLocation());
}
return null;
}
final MethodHandle cmh = constantGetter(c);
MethodHandle mh;
MethodHandle guard;
if (isOptimistic) {
if (JSType.getAccessorTypeIndex(cmh.type().returnType()) <= JSType.getAccessorTypeIndex(retType)) {
//widen return type - this is pessimistic, so it will always work
mh = MH.asType(cmh, cmh.type().changeReturnType(retType));
} else {
//immediately invalidate - we asked for a too wide constant as a narrower one
mh = MH.dropArguments(MH.insertArguments(JSType.THROW_UNWARRANTED.methodHandle(), 0, c, programPoint), 0, Object.class);
}
} else {
//pessimistic return type filter
mh = Lookup.filterReturnType(cmh, retType);
}
if (find.getOwner().isGlobal()) {
guard = null;
} else {
guard = MH.insertArguments(RECEIVER_GUARD, 0, acc, receiver);
}
if (log.isEnabled()) {
log.info("Linked getter " + quote(name) + " as MethodHandle.constant() -> " + c + " " + acc.getSwitchPoint());
mh = MethodHandleFactory.addDebugPrintout(log, Level.FINE, mh, "get const " + acc);
}
return new GuardedInvocation(mh, guard, acc.getSwitchPoint(), null);
}
}
