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8173227: [JVMCI] HotSpotJVMCIMetaAccessContext.fromClass is inefficient

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Reviewed-by: dnsimon
This commit is contained in:
Tom Rodriguez 2017-01-30 17:29:48 -08:00
parent 710612ff65
commit 48341996cf
1 changed files with 21 additions and 10 deletions
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31
hotspot/src/jdk.vm.ci/share/classes/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/HotSpotJVMCIMetaAccessContext.java
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@ -27,8 +27,6 @@ import java.lang.ref.ReferenceQueue;
import java.lang.ref.WeakReference;
import java.util.Arrays;
import java.util.Iterator;
import java.util.Map;
import java.util.WeakHashMap;
import jdk.vm.ci.meta.JavaKind;
import jdk.vm.ci.meta.ResolvedJavaType;
@ -147,21 +145,34 @@ public class HotSpotJVMCIMetaAccessContext {
}
}
private final Map<Class<?>, WeakReference<ResolvedJavaType>> typeMap = new WeakHashMap<>();
private final ClassValue<WeakReference<ResolvedJavaType>> resolvedJavaType = new ClassValue<WeakReference<ResolvedJavaType>>() {
@Override
protected WeakReference<ResolvedJavaType> computeValue(Class<?> type) {
return new WeakReference<>(createClass(type));
}
};
/**
* Gets the JVMCI mirror for a {@link Class} object.
*
* @return the {@link ResolvedJavaType} corresponding to {@code javaClass}
*/
public synchronized ResolvedJavaType fromClass(Class<?> javaClass) {
WeakReference<ResolvedJavaType> typeRef = typeMap.get(javaClass);
ResolvedJavaType type = typeRef != null ? typeRef.get() : null;
if (type == null) {
type = createClass(javaClass);
typeMap.put(javaClass, new WeakReference<>(type));
public ResolvedJavaType fromClass(Class<?> javaClass) {
ResolvedJavaType javaType = null;
while (javaType == null) {
WeakReference<ResolvedJavaType> type = resolvedJavaType.get(javaClass);
javaType = type.get();
if (javaType == null) {
/*
* If the referent has become null, clear out the current value
* and let computeValue above create a new value. Reload the
* value in a loop because in theory the WeakReference referent
* can be reclaimed at any point.
*/
resolvedJavaType.remove(javaClass);
}
return type;
}
return javaType;
}
/**