Mercurial > hg > graal-jvmci-8
view jvmci/jdk.vm.ci.hotspot/src/jdk/vm/ci/hotspot/HotSpotConstantReflectionProvider.java @ 23357:b05ad394cfd5
Add ResolvedJavaType.isAllocationClonable
author | Tom Rodriguez <tom.rodriguez@oracle.com> |
---|---|
date | Thu, 28 Apr 2016 13:07:46 -0700 |
parents | f895a46e0a45 |
children | f102ee538647 |
line wrap: on
line source
/* * Copyright (c) 2011, 2015, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * 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 * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package jdk.vm.ci.hotspot; import static jdk.vm.ci.hotspot.HotSpotJVMCIRuntimeProvider.getArrayBaseOffset; import static jdk.vm.ci.hotspot.HotSpotJVMCIRuntimeProvider.getArrayIndexScale; import java.lang.reflect.Array; import jdk.vm.ci.common.JVMCIError; import jdk.vm.ci.hotspot.HotSpotJVMCIRuntime.Option; import jdk.vm.ci.meta.Constant; import jdk.vm.ci.meta.ConstantReflectionProvider; import jdk.vm.ci.meta.JavaConstant; import jdk.vm.ci.meta.JavaKind; import jdk.vm.ci.meta.JavaType; import jdk.vm.ci.meta.MemoryAccessProvider; import jdk.vm.ci.meta.MethodHandleAccessProvider; import jdk.vm.ci.meta.ResolvedJavaField; import jdk.vm.ci.meta.ResolvedJavaType; /** * HotSpot implementation of {@link ConstantReflectionProvider}. */ public class HotSpotConstantReflectionProvider implements ConstantReflectionProvider, HotSpotProxified { protected final HotSpotJVMCIRuntimeProvider runtime; protected final HotSpotMethodHandleAccessProvider methodHandleAccess; protected final HotSpotMemoryAccessProviderImpl memoryAccess; public HotSpotConstantReflectionProvider(HotSpotJVMCIRuntimeProvider runtime) { this.runtime = runtime; this.methodHandleAccess = new HotSpotMethodHandleAccessProvider(this); this.memoryAccess = new HotSpotMemoryAccessProviderImpl(runtime); } public MethodHandleAccessProvider getMethodHandleAccess() { return methodHandleAccess; } @Override public MemoryAccessProvider getMemoryAccessProvider() { return memoryAccess; } @Override public Boolean constantEquals(Constant x, Constant y) { if (x == y) { return true; } else if (x instanceof HotSpotObjectConstantImpl) { return y instanceof HotSpotObjectConstantImpl && ((HotSpotObjectConstantImpl) x).object() == ((HotSpotObjectConstantImpl) y).object(); } else { return x.equals(y); } } @Override public Integer readArrayLength(JavaConstant array) { if (array.getJavaKind() != JavaKind.Object || array.isNull()) { return null; } Object arrayObject = ((HotSpotObjectConstantImpl) array).object(); if (!arrayObject.getClass().isArray()) { return null; } return Array.getLength(arrayObject); } public JavaConstant readConstantArrayElement(JavaConstant array, int index) { if (array instanceof HotSpotObjectConstantImpl && ((HotSpotObjectConstantImpl) array).getStableDimension() > 0) { JavaConstant element = readArrayElement(array, index); if (element != null && (((HotSpotObjectConstantImpl) array).isDefaultStable() || !element.isDefaultForKind())) { return element; } } return null; } /** * Try to convert {@code offset} into an an index into {@code array}. * * @return the computed index or -1 if the offset isn't within the array */ private int indexForOffset(JavaConstant array, long offset) { if (array.getJavaKind() != JavaKind.Object || array.isNull()) { return -1; } Class<?> componentType = ((HotSpotObjectConstantImpl) array).object().getClass().getComponentType(); JavaKind kind = runtime.getHostJVMCIBackend().getMetaAccess().lookupJavaType(componentType).getJavaKind(); int arraybase = getArrayBaseOffset(kind); int scale = getArrayIndexScale(kind); if (offset < arraybase) { return -1; } long index = offset - arraybase; if (index % scale != 0) { return -1; } long result = index / scale; if (result >= Integer.MAX_VALUE) { return -1; } return (int) result; } public JavaConstant readConstantArrayElementForOffset(JavaConstant array, long offset) { if (array instanceof HotSpotObjectConstantImpl && ((HotSpotObjectConstantImpl) array).getStableDimension() > 0) { return readConstantArrayElement(array, indexForOffset(array, offset)); } return null; } @Override public JavaConstant readArrayElement(JavaConstant array, int index) { if (array.getJavaKind() != JavaKind.Object || array.isNull()) { return null; } Object a = ((HotSpotObjectConstantImpl) array).object(); if (index < 0 || index >= Array.getLength(a)) { return null; } if (a instanceof Object[]) { Object element = ((Object[]) a)[index]; if (((HotSpotObjectConstantImpl) array).getStableDimension() > 1) { return HotSpotObjectConstantImpl.forStableArray(element, ((HotSpotObjectConstantImpl) array).getStableDimension() - 1, ((HotSpotObjectConstantImpl) array).isDefaultStable()); } else { return HotSpotObjectConstantImpl.forObject(element); } } else { return JavaConstant.forBoxedPrimitive(Array.get(a, index)); } } /** * Check if the constant is a boxed value that is guaranteed to be cached by the platform. * Otherwise the generated code might be the only reference to the boxed value and since object * references from nmethods are weak this can cause GC problems. * * @param source * @return true if the box is cached */ private static boolean isBoxCached(JavaConstant source) { switch (source.getJavaKind()) { case Boolean: return true; case Char: return source.asInt() <= 127; case Byte: case Short: case Int: return source.asInt() >= -128 && source.asInt() <= 127; case Long: return source.asLong() >= -128 && source.asLong() <= 127; case Float: case Double: return false; default: throw new IllegalArgumentException("unexpected kind " + source.getJavaKind()); } } @Override public JavaConstant boxPrimitive(JavaConstant source) { if (!source.getJavaKind().isPrimitive() || !isBoxCached(source)) { return null; } return HotSpotObjectConstantImpl.forObject(source.asBoxedPrimitive()); } @Override public JavaConstant unboxPrimitive(JavaConstant source) { if (!source.getJavaKind().isObject()) { return null; } if (source.isNull()) { return null; } return JavaConstant.forBoxedPrimitive(((HotSpotObjectConstantImpl) source).object()); } public JavaConstant forString(String value) { return HotSpotObjectConstantImpl.forObject(value); } public JavaConstant forObject(Object value) { return HotSpotObjectConstantImpl.forObject(value); } @Override public ResolvedJavaType asJavaType(Constant constant) { if (constant instanceof HotSpotObjectConstant) { Object obj = ((HotSpotObjectConstantImpl) constant).object(); if (obj instanceof Class) { return runtime.getHostJVMCIBackend().getMetaAccess().lookupJavaType((Class<?>) obj); } } if (constant instanceof HotSpotMetaspaceConstant) { MetaspaceWrapperObject obj = HotSpotMetaspaceConstantImpl.getMetaspaceObject(constant); if (obj instanceof HotSpotResolvedObjectTypeImpl) { return (ResolvedJavaType) obj; } } return null; } private static final String SystemClassName = "Ljava/lang/System;"; /** * Determines if a static field is constant for the purpose of * {@link #readConstantFieldValue(ResolvedJavaField, JavaConstant)}. */ protected boolean isStaticFieldConstant(HotSpotResolvedJavaField staticField) { if (staticField.isFinal() || (staticField.isStable() && runtime.getConfig().foldStableValues)) { ResolvedJavaType holder = staticField.getDeclaringClass(); if (holder.isInitialized() && !holder.getName().equals(SystemClassName)) { return true; } } return false; } /** * Determines if a value read from a {@code final} instance field is considered constant. The * implementation in {@link HotSpotConstantReflectionProvider} returns true if {@code value} is * not the {@link JavaConstant#isDefaultForKind default value} for its kind or if * {@link Option#TrustFinalDefaultFields} is true. * * @param value a value read from a {@code final} instance field * @param receiverClass the {@link Object#getClass() class} of object from which the * {@code value} was read */ protected boolean isFinalInstanceFieldValueConstant(JavaConstant value, Class<?> receiverClass) { return !value.isDefaultForKind() || Option.TrustFinalDefaultFields.getBoolean(); } /** * Determines if a value read from a {@link Stable} instance field is considered constant. The * implementation in {@link HotSpotConstantReflectionProvider} returns true if {@code value} is * not the {@link JavaConstant#isDefaultForKind default value} for its kind. * * @param value a value read from a {@link Stable} field * @param receiverClass the {@link Object#getClass() class} of object from which the * {@code value} was read */ protected boolean isStableInstanceFieldValueConstant(JavaConstant value, Class<?> receiverClass) { return !value.isDefaultForKind(); } public JavaConstant readConstantFieldValue(ResolvedJavaField field, JavaConstant receiver) { HotSpotResolvedJavaField hotspotField = (HotSpotResolvedJavaField) field; if (hotspotField.isStatic()) { if (isStaticFieldConstant(hotspotField)) { JavaConstant value = readFieldValue(field, receiver); if (hotspotField.isFinal() || !value.isDefaultForKind()) { return value; } } } else { /* * for non-static final fields, we must assume that they are only initialized if they * have a non-default value. */ Object object = receiver.isNull() ? null : ((HotSpotObjectConstantImpl) receiver).object(); // Canonicalization may attempt to process an unsafe read before // processing a guard (e.g. a null check or a type check) for this read // so we need to check the object being read if (object != null) { if (hotspotField.isFinal()) { if (hotspotField.isInObject(object)) { JavaConstant value = readFieldValue(field, receiver); if (isFinalInstanceFieldValueConstant(value, object.getClass())) { return value; } } } else if (hotspotField.isStable() && runtime.getConfig().foldStableValues) { if (hotspotField.isInObject(object)) { JavaConstant value = readFieldValue(field, receiver); if (isStableInstanceFieldValueConstant(value, object.getClass())) { return value; } } } } } return null; } public JavaConstant readFieldValue(ResolvedJavaField field, JavaConstant receiver) { HotSpotResolvedJavaField hotspotField = (HotSpotResolvedJavaField) field; if (!hotspotField.isStable()) { return readNonStableFieldValue(field, receiver); } else if (runtime.getConfig().foldStableValues) { return readStableFieldValue(field, receiver, hotspotField.isDefaultStable()); } else { return null; } } private JavaConstant readNonStableFieldValue(ResolvedJavaField field, JavaConstant receiver) { HotSpotResolvedJavaField hotspotField = (HotSpotResolvedJavaField) field; if (hotspotField.isStatic()) { HotSpotResolvedJavaType holder = (HotSpotResolvedJavaType) hotspotField.getDeclaringClass(); if (holder.isInitialized()) { return memoryAccess.readUnsafeConstant(hotspotField.getJavaKind(), HotSpotObjectConstantImpl.forObject(holder.mirror()), hotspotField.offset()); } } else { if (receiver.isNonNull() && hotspotField.isInObject(((HotSpotObjectConstantImpl) receiver).object())) { return memoryAccess.readUnsafeConstant(hotspotField.getJavaKind(), receiver, hotspotField.offset()); } } return null; } public JavaConstant readStableFieldValue(ResolvedJavaField field, JavaConstant receiver, boolean isDefaultStable) { JavaConstant fieldValue = readNonStableFieldValue(field, receiver); if (fieldValue != null && fieldValue.isNonNull()) { JavaType declaredType = field.getType(); if (declaredType.getComponentType() != null) { int stableDimension = getArrayDimension(declaredType); return HotSpotObjectConstantImpl.forStableArray(((HotSpotObjectConstantImpl) fieldValue).object(), stableDimension, isDefaultStable); } } return fieldValue; } private static int getArrayDimension(JavaType type) { int dimensions = 0; JavaType componentType = type; while ((componentType = componentType.getComponentType()) != null) { dimensions++; } return dimensions; } @Override public JavaConstant asJavaClass(ResolvedJavaType type) { return HotSpotObjectConstantImpl.forObject(((HotSpotResolvedJavaType) type).mirror()); } @Override public Constant asObjectHub(ResolvedJavaType type) { if (type instanceof HotSpotResolvedObjectType) { return ((HotSpotResolvedObjectType) type).klass(); } else { throw JVMCIError.unimplemented(); } } }