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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
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package org.graalvm.compiler.virtual.phases.ea;

import java.util.Iterator;

import jdk.internal.vm.compiler.collections.EconomicMap;
import jdk.internal.vm.compiler.collections.Equivalence;
import org.graalvm.compiler.nodes.ValueNode;
import jdk.internal.vm.compiler.word.LocationIdentity;

This class maintains a set of known values, identified by base object, locations and offset.
/** * This class maintains a set of known values, identified by base object, locations and offset. */
public final class ReadEliminationBlockState extends EffectsBlockState<ReadEliminationBlockState> { final EconomicMap<CacheEntry<?>, ValueNode> readCache; abstract static class CacheEntry<T> { public final ValueNode object; public final T identity; CacheEntry(ValueNode object, T identity) { this.object = object; this.identity = identity; } public abstract CacheEntry<T> duplicateWithObject(ValueNode newObject); @Override public int hashCode() { int result = 31 + ((identity == null) ? 0 : identity.hashCode()); return 31 * result + ((object == null) ? 0 : object.hashCode()); } @Override public boolean equals(Object obj) { if (!(obj instanceof CacheEntry<?>)) { return false; } CacheEntry<?> other = (CacheEntry<?>) obj; return identity.equals(other.identity) && object == other.object; } @Override public String toString() { return object + ":" + identity; } public abstract boolean conflicts(LocationIdentity other); public abstract LocationIdentity getIdentity(); } static final class LoadCacheEntry extends CacheEntry<LocationIdentity> { LoadCacheEntry(ValueNode object, LocationIdentity identity) { super(object, identity); } @Override public CacheEntry<LocationIdentity> duplicateWithObject(ValueNode newObject) { return new LoadCacheEntry(newObject, identity); } @Override public boolean conflicts(LocationIdentity other) { return identity.equals(other); } @Override public LocationIdentity getIdentity() { return identity; } }
CacheEntry describing an Unsafe memory reference. The memory location and the location identity are separate so both must be considered when looking for optimizable memory accesses.
/** * CacheEntry describing an Unsafe memory reference. The memory location and the location * identity are separate so both must be considered when looking for optimizable memory * accesses. */
static final class UnsafeLoadCacheEntry extends CacheEntry<ValueNode> { private final LocationIdentity locationIdentity; UnsafeLoadCacheEntry(ValueNode object, ValueNode location, LocationIdentity locationIdentity) { super(object, location); assert locationIdentity != null; this.locationIdentity = locationIdentity; } @Override public CacheEntry<ValueNode> duplicateWithObject(ValueNode newObject) { return new UnsafeLoadCacheEntry(newObject, identity, locationIdentity); } @Override public boolean conflicts(LocationIdentity other) { return locationIdentity.equals(other); } @Override public int hashCode() { return 31 * super.hashCode() + locationIdentity.hashCode(); } @Override public boolean equals(Object obj) { if (obj instanceof UnsafeLoadCacheEntry) { UnsafeLoadCacheEntry other = (UnsafeLoadCacheEntry) obj; return super.equals(other) && locationIdentity.equals(other.locationIdentity); } return false; } @Override public LocationIdentity getIdentity() { return locationIdentity; } @Override public String toString() { return "UNSAFE:" + super.toString() + " location:" + locationIdentity; } } public ReadEliminationBlockState() { readCache = EconomicMap.create(Equivalence.DEFAULT); } public ReadEliminationBlockState(ReadEliminationBlockState other) { readCache = EconomicMap.create(Equivalence.DEFAULT, other.readCache); } @Override public String toString() { return super.toString() + " " + readCache; } @Override public boolean equivalentTo(ReadEliminationBlockState other) { return isSubMapOf(readCache, other.readCache); } public void addCacheEntry(CacheEntry<?> identifier, ValueNode value) { readCache.put(identifier, value); } public ValueNode getCacheEntry(CacheEntry<?> identifier) { return readCache.get(identifier); } public void killReadCache() { readCache.clear(); } public void killReadCache(LocationIdentity identity) { Iterator<CacheEntry<?>> iterator = readCache.getKeys().iterator(); while (iterator.hasNext()) { CacheEntry<?> entry = iterator.next(); if (entry.conflicts(identity)) { iterator.remove(); } } } public EconomicMap<CacheEntry<?>, ValueNode> getReadCache() { return readCache; } }