/*
 * Copyright (c) 2012, 2018, 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 org.graalvm.compiler.hotspot.replacements;

import static org.graalvm.compiler.hotspot.GraalHotSpotVMConfigBase.INJECTED_METAACCESS;
import static org.graalvm.compiler.hotspot.GraalHotSpotVMConfigBase.INJECTED_VMCONFIG;
import static org.graalvm.compiler.hotspot.meta.HotSpotForeignCallsProviderImpl.VERIFY_OOP;

import java.lang.ref.Reference;

import org.graalvm.compiler.api.replacements.Fold;
import org.graalvm.compiler.api.replacements.Fold.InjectedParameter;
import org.graalvm.compiler.core.common.SuppressFBWarnings;
import org.graalvm.compiler.core.common.spi.ForeignCallDescriptor;
import org.graalvm.compiler.core.common.type.ObjectStamp;
import org.graalvm.compiler.core.common.type.TypeReference;
import org.graalvm.compiler.debug.GraalError;
import org.graalvm.compiler.graph.Node.ConstantNodeParameter;
import org.graalvm.compiler.graph.Node.NodeIntrinsic;
import org.graalvm.compiler.graph.spi.CanonicalizerTool;
import org.graalvm.compiler.hotspot.GraalHotSpotVMConfig;
import org.graalvm.compiler.hotspot.word.KlassPointer;
import org.graalvm.compiler.nodes.CanonicalizableLocation;
import org.graalvm.compiler.nodes.CompressionNode;
import org.graalvm.compiler.nodes.ComputeObjectAddressNode;
import org.graalvm.compiler.nodes.ConstantNode;
import org.graalvm.compiler.nodes.NamedLocationIdentity;
import org.graalvm.compiler.nodes.NodeView;
import org.graalvm.compiler.nodes.ValueNode;
import org.graalvm.compiler.nodes.extended.ForeignCallNode;
import org.graalvm.compiler.nodes.extended.LoadHubNode;
import org.graalvm.compiler.nodes.extended.RawLoadNode;
import org.graalvm.compiler.nodes.extended.StoreHubNode;
import org.graalvm.compiler.nodes.graphbuilderconf.IntrinsicContext;
import org.graalvm.compiler.nodes.memory.Access;
import org.graalvm.compiler.nodes.memory.address.AddressNode;
import org.graalvm.compiler.nodes.memory.address.OffsetAddressNode;
import org.graalvm.compiler.nodes.type.StampTool;
import org.graalvm.compiler.replacements.ReplacementsUtil;
import org.graalvm.compiler.replacements.nodes.ReadRegisterNode;
import org.graalvm.compiler.replacements.nodes.WriteRegisterNode;
import org.graalvm.compiler.word.Word;
import jdk.internal.vm.compiler.word.LocationIdentity;
import jdk.internal.vm.compiler.word.WordFactory;

import jdk.vm.ci.code.Register;
import jdk.vm.ci.hotspot.HotSpotJVMCIRuntime;
import jdk.vm.ci.hotspot.HotSpotMetaspaceConstant;
import jdk.vm.ci.hotspot.HotSpotResolvedObjectType;
import jdk.vm.ci.meta.Assumptions;
import jdk.vm.ci.meta.Assumptions.AssumptionResult;
import jdk.vm.ci.meta.JavaKind;
import jdk.vm.ci.meta.MetaAccessProvider;
import jdk.vm.ci.meta.ResolvedJavaField;
import jdk.vm.ci.meta.ResolvedJavaType;
import jdk.vm.ci.meta.UnresolvedJavaType;

//JaCoCo Exclude

A collection of methods used in HotSpot snippets, substitutions and stubs.
/**
 * A collection of methods used in HotSpot snippets, substitutions and stubs.
 */
public class HotSpotReplacementsUtil {

    abstract static class HotSpotOptimizingLocationIdentity extends NamedLocationIdentity implements CanonicalizableLocation {

        HotSpotOptimizingLocationIdentity(String name) {
            super(name, true);
        }

        @Override
        public abstract ValueNode canonicalizeRead(ValueNode read, AddressNode location, ValueNode object, CanonicalizerTool tool);

        protected ValueNode findReadHub(ValueNode object) {
            ValueNode base = object;
            if (base instanceof CompressionNode) {
                base = ((CompressionNode) base).getValue();
            }
            if (base instanceof Access) {
                Access access = (Access) base;
                if (access.getLocationIdentity().equals(HUB_LOCATION) || access.getLocationIdentity().equals(COMPRESSED_HUB_LOCATION)) {
                    AddressNode address = access.getAddress();
                    if (address instanceof OffsetAddressNode) {
                        OffsetAddressNode offset = (OffsetAddressNode) address;
                        return offset.getBase();
                    }
                }
            } else if (base instanceof LoadHubNode) {
                LoadHubNode loadhub = (LoadHubNode) base;
                return loadhub.getValue();
            }
            return null;
        }

        
Fold reads that convert from Class -> Hub -> Class or vice versa.
Params:
read – 
object – 
otherLocation – 
Returns:
an earlier read or the original read/**
         * Fold reads that convert from Class -> Hub -> Class or vice versa.
         *
         * @param read
         * @param object
         * @param otherLocation
         * @return an earlier read or the original {@code read}
         */
        protected static ValueNode foldIndirection(ValueNode read, ValueNode object, LocationIdentity otherLocation) {
            if (object instanceof Access) {
                Access access = (Access) object;
                if (access.getLocationIdentity().equals(otherLocation)) {
                    AddressNode address = access.getAddress();
                    if (address instanceof OffsetAddressNode) {
                        OffsetAddressNode offset = (OffsetAddressNode) address;
                        assert offset.getBase().stamp(NodeView.DEFAULT).isCompatible(read.stamp(NodeView.DEFAULT));
                        return offset.getBase();
                    }
                }
            }
            return read;
        }
    }

    public static ResolvedJavaType methodHolderClass(@Fold.InjectedParameter IntrinsicContext context) {
        return context.getOriginalMethod().getDeclaringClass();
    }

    static ResolvedJavaType getType(@Fold.InjectedParameter IntrinsicContext context, String typeName) {
        try {
            UnresolvedJavaType unresolved = UnresolvedJavaType.create(typeName);
            return unresolved.resolve(methodHolderClass(context));
        } catch (LinkageError e) {
            throw new GraalError(e);
        }
    }

    static int getFieldOffset(ResolvedJavaType type, String fieldName) {
        for (ResolvedJavaField field : type.getInstanceFields(true)) {
            if (field.getName().equals(fieldName)) {
                return field.getOffset();
            }
        }
        throw new GraalError("missing field " + fieldName);
    }

    public static HotSpotJVMCIRuntime runtime() {
        return HotSpotJVMCIRuntime.runtime();
    }

    @Fold
    public static int getHeapWordSize(@InjectedParameter GraalHotSpotVMConfig injectedVMConfig) {
        return injectedVMConfig.heapWordSize;
    }

    @Fold
    public static int klassLayoutHelperNeutralValue(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.klassLayoutHelperNeutralValue;
    }

    @Fold
    public static boolean useTLAB(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.useTLAB;
    }

    @Fold
    public static boolean verifyOops(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.verifyOops;
    }

    public static final LocationIdentity EXCEPTION_OOP_LOCATION = NamedLocationIdentity.mutable("ExceptionOop");

    
See Also:
threadExceptionOopOffset.threadExceptionOopOffset/**
     * @see GraalHotSpotVMConfig#threadExceptionOopOffset
     */
    @Fold
    public static int threadExceptionOopOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.threadExceptionOopOffset;
    }

    public static final LocationIdentity EXCEPTION_PC_LOCATION = NamedLocationIdentity.mutable("ExceptionPc");

    @Fold
    public static int threadExceptionPcOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.threadExceptionPcOffset;
    }

    public static final LocationIdentity TLAB_TOP_LOCATION = NamedLocationIdentity.mutable("TlabTop");

    @Fold
    public static int threadTlabTopOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.threadTlabTopOffset();
    }

    public static final LocationIdentity TLAB_END_LOCATION = NamedLocationIdentity.mutable("TlabEnd");

    @Fold
    static int threadTlabEndOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.threadTlabEndOffset();
    }

    public static final LocationIdentity PENDING_EXCEPTION_LOCATION = NamedLocationIdentity.mutable("PendingException");

    
See Also:
pendingExceptionOffset.pendingExceptionOffset/**
     * @see GraalHotSpotVMConfig#pendingExceptionOffset
     */
    @Fold
    static int threadPendingExceptionOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.pendingExceptionOffset;
    }

    
See Also:
threadExceptionOopOffset.threadExceptionOopOffset/**
     * @see GraalHotSpotVMConfig#threadExceptionOopOffset
     */
    public static Object readExceptionOop(Word thread) {
        return thread.readObject(threadExceptionOopOffset(INJECTED_VMCONFIG), EXCEPTION_OOP_LOCATION);
    }

    public static Word readExceptionPc(Word thread) {
        return thread.readWord(threadExceptionPcOffset(INJECTED_VMCONFIG), EXCEPTION_PC_LOCATION);
    }

    
See Also:
threadExceptionOopOffset.threadExceptionOopOffset/**
     * @see GraalHotSpotVMConfig#threadExceptionOopOffset
     */
    public static void writeExceptionOop(Word thread, Object value) {
        thread.writeObject(threadExceptionOopOffset(INJECTED_VMCONFIG), value, EXCEPTION_OOP_LOCATION);
    }

    public static void writeExceptionPc(Word thread, Word value) {
        thread.writeWord(threadExceptionPcOffset(INJECTED_VMCONFIG), value, EXCEPTION_PC_LOCATION);
    }

    public static Word readTlabTop(Word thread) {
        return thread.readWord(threadTlabTopOffset(INJECTED_VMCONFIG), TLAB_TOP_LOCATION);
    }

    public static Word readTlabEnd(Word thread) {
        return thread.readWord(threadTlabEndOffset(INJECTED_VMCONFIG), TLAB_END_LOCATION);
    }

    public static void writeTlabTop(Word thread, Word top) {
        thread.writeWord(threadTlabTopOffset(INJECTED_VMCONFIG), top, TLAB_TOP_LOCATION);
    }

    
Clears the pending exception for the given thread.
Returns:
the pending exception, or null if there was none/**
     * Clears the pending exception for the given thread.
     *
     * @return the pending exception, or null if there was none
     */
    @SuppressFBWarnings(value = "NP_NULL_PARAM_DEREF_NONVIRTUAL", justification = "foldable method parameters are injected")
    public static Object clearPendingException(Word thread) {
        Object result = thread.readObject(threadPendingExceptionOffset(INJECTED_VMCONFIG), PENDING_EXCEPTION_LOCATION);
        thread.writeObject(threadPendingExceptionOffset(INJECTED_VMCONFIG), null, PENDING_EXCEPTION_LOCATION);
        return result;
    }

    
Gets the pending exception for the given thread.
Returns:
the pending exception, or null if there was none/**
     * Gets the pending exception for the given thread.
     *
     * @return the pending exception, or null if there was none
     */
    @SuppressFBWarnings(value = "NP_NULL_PARAM_DEREF_NONVIRTUAL", justification = "foldable method parameters are injected")
    public static Object getPendingException(Word thread) {
        return thread.readObject(threadPendingExceptionOffset(INJECTED_VMCONFIG), PENDING_EXCEPTION_LOCATION);
    }

    /*
     * As far as Java code is concerned this can be considered immutable: it is set just after the
     * JavaThread is created, before it is published. After that, it is never changed.
     */
    public static final LocationIdentity JAVA_THREAD_THREAD_OBJECT_LOCATION = NamedLocationIdentity.immutable("JavaThread::_threadObj");

    @Fold
    public static int threadObjectOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.threadObjectOffset;
    }

    public static final LocationIdentity JAVA_THREAD_OSTHREAD_LOCATION = NamedLocationIdentity.mutable("JavaThread::_osthread");

    @Fold
    public static int osThreadOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.osThreadOffset;
    }

    @Fold
    public static int osThreadInterruptedOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.osThreadInterruptedOffset;
    }

    @Fold
    public static JavaKind getWordKind() {
        return runtime().getHostJVMCIBackend().getCodeCache().getTarget().wordJavaKind;
    }

    @Fold
    public static int wordSize() {
        return runtime().getHostJVMCIBackend().getCodeCache().getTarget().wordSize;
    }

    @Fold
    public static int pageSize(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.vmPageSize;
    }

    public static final LocationIdentity PROTOTYPE_MARK_WORD_LOCATION = NamedLocationIdentity.mutable("PrototypeMarkWord");

    @Fold
    public static int prototypeMarkWordOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.prototypeMarkWordOffset;
    }

    public static final LocationIdentity KLASS_ACCESS_FLAGS_LOCATION = NamedLocationIdentity.immutable("Klass::_access_flags");

    @Fold
    public static int klassAccessFlagsOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.klassAccessFlagsOffset;
    }

    @Fold
    public static int jvmAccWrittenFlags(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.jvmAccWrittenFlags;
    }

    public static final LocationIdentity KLASS_LAYOUT_HELPER_LOCATION = new HotSpotOptimizingLocationIdentity("Klass::_layout_helper") {
        @Override
        public ValueNode canonicalizeRead(ValueNode read, AddressNode location, ValueNode object, CanonicalizerTool tool) {
            ValueNode javaObject = findReadHub(object);
            if (javaObject != null) {
                if (javaObject.stamp(NodeView.DEFAULT) instanceof ObjectStamp) {
                    ObjectStamp stamp = (ObjectStamp) javaObject.stamp(NodeView.DEFAULT);
                    HotSpotResolvedObjectType type = (HotSpotResolvedObjectType) stamp.javaType(tool.getMetaAccess());
                    if (type.isArray() && !type.getComponentType().isPrimitive()) {
                        int layout = type.layoutHelper();
                        return ConstantNode.forInt(layout);
                    }
                }
            }
            return read;
        }
    };

    @Fold
    public static int allocatePrefetchStyle(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.allocatePrefetchStyle;
    }

    @Fold
    public static int allocatePrefetchLines(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.allocatePrefetchLines;
    }

    @Fold
    public static int allocatePrefetchDistance(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.allocatePrefetchDistance;
    }

    @Fold
    public static int allocateInstancePrefetchLines(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.allocateInstancePrefetchLines;
    }

    @Fold
    public static int allocatePrefetchStepSize(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.allocatePrefetchStepSize;
    }

    @Fold
    public static int invocationCounterIncrement(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.invocationCounterIncrement;
    }

    @Fold
    public static int invocationCounterOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.invocationCounterOffset;
    }

    @Fold
    public static int backedgeCounterOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.backedgeCounterOffset;
    }

    @Fold
    public static int invocationCounterShift(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.invocationCounterShift;
    }

    @Fold
    public static int stackBias(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.stackBias;
    }

    @NodeIntrinsic(value = KlassLayoutHelperNode.class)
    public static native int readLayoutHelper(KlassPointer object);

    
Checks if class klass is an array. See: Klass::layout_helper_is_array 
Params:
klassNonNull – the class to be checked
Returns:
true if klassNonNull is an array, false otherwise/**
     * Checks if class {@code klass} is an array.
     *
     * See: Klass::layout_helper_is_array
     *
     * @param klassNonNull the class to be checked
     * @return true if klassNonNull is an array, false otherwise
     */
    public static boolean klassIsArray(KlassPointer klassNonNull) {
        /*
         * The less-than check only works if both values are ints. We use local variables to make
         * sure these are still ints and haven't changed.
         */
        final int layoutHelper = readLayoutHelper(klassNonNull);
        final int layoutHelperNeutralValue = klassLayoutHelperNeutralValue(INJECTED_VMCONFIG);
        return (layoutHelper < layoutHelperNeutralValue);
    }

    public static final LocationIdentity ARRAY_KLASS_COMPONENT_MIRROR = NamedLocationIdentity.immutable("ArrayKlass::_component_mirror");

    @Fold
    public static int arrayKlassComponentMirrorOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.getFieldOffset("ArrayKlass::_component_mirror", Integer.class, "oop");
    }

    public static final LocationIdentity KLASS_SUPER_KLASS_LOCATION = NamedLocationIdentity.immutable("Klass::_super");

    @Fold
    public static int klassSuperKlassOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.klassSuperKlassOffset;
    }

    public static final LocationIdentity MARK_WORD_LOCATION = NamedLocationIdentity.mutable("MarkWord");

    @Fold
    public static int markOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.markOffset;
    }

    public static final LocationIdentity HUB_WRITE_LOCATION = NamedLocationIdentity.mutable("Hub:write");

    public static final LocationIdentity HUB_LOCATION = new HotSpotOptimizingLocationIdentity("Hub") {
        @Override
        public ValueNode canonicalizeRead(ValueNode read, AddressNode location, ValueNode object, CanonicalizerTool tool) {
            TypeReference constantType = StampTool.typeReferenceOrNull(object);
            if (constantType != null && constantType.isExact()) {
                return ConstantNode.forConstant(read.stamp(NodeView.DEFAULT), tool.getConstantReflection().asObjectHub(constantType.getType()), tool.getMetaAccess());
            }
            return read;
        }
    };

    public static final LocationIdentity COMPRESSED_HUB_LOCATION = new HotSpotOptimizingLocationIdentity("CompressedHub") {
        @Override
        public ValueNode canonicalizeRead(ValueNode read, AddressNode location, ValueNode object, CanonicalizerTool tool) {
            TypeReference constantType = StampTool.typeReferenceOrNull(object);
            if (constantType != null && constantType.isExact()) {
                return ConstantNode.forConstant(read.stamp(NodeView.DEFAULT), ((HotSpotMetaspaceConstant) tool.getConstantReflection().asObjectHub(constantType.getType())).compress(),
                                tool.getMetaAccess());
            }
            return read;
        }
    };

    @Fold
    static int hubOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.hubOffset;
    }

    public static void initializeObjectHeader(Word memory, Word markWord, KlassPointer hub) {
        memory.writeWord(markOffset(INJECTED_VMCONFIG), markWord, MARK_WORD_LOCATION);
        StoreHubNode.write(memory, hub);
    }

    @Fold
    public static int unlockedMask(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.unlockedMask;
    }

    @Fold
    public static int monitorMask(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.monitorMask;
    }

    @Fold
    public static int objectMonitorOwnerOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.objectMonitorOwner;
    }

    @Fold
    public static int objectMonitorRecursionsOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.objectMonitorRecursions;
    }

    @Fold
    public static int objectMonitorCxqOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.objectMonitorCxq;
    }

    @Fold
    public static int objectMonitorEntryListOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.objectMonitorEntryList;
    }

    
Mask for a biasable, locked or unlocked mark word.
+----------------------------------+-+-+
|                                 1|1|1|
+----------------------------------+-+-+

/**
     * Mask for a biasable, locked or unlocked mark word.
     *
     * <pre>
     * +----------------------------------+-+-+
     * |                                 1|1|1|
     * +----------------------------------+-+-+
     * </pre>
     *
     */
    @Fold
    public static int biasedLockMaskInPlace(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.biasedLockMaskInPlace;
    }

    @Fold
    public static int epochMaskInPlace(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.epochMaskInPlace;
    }

    
Pattern for a biasable, unlocked mark word.
+----------------------------------+-+-+
|                                 1|0|1|
+----------------------------------+-+-+

/**
     * Pattern for a biasable, unlocked mark word.
     *
     * <pre>
     * +----------------------------------+-+-+
     * |                                 1|0|1|
     * +----------------------------------+-+-+
     * </pre>
     *
     */
    @Fold
    public static int biasedLockPattern(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.biasedLockPattern;
    }

    @Fold
    public static int ageMaskInPlace(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.ageMaskInPlace;
    }

    @Fold
    public static int metaspaceArrayLengthOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.metaspaceArrayLengthOffset;
    }

    @Fold
    public static int metaspaceArrayBaseOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.metaspaceArrayBaseOffset;
    }

    @Fold
    public static int arrayLengthOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.arrayOopDescLengthOffset();
    }

    public static Word arrayStart(int[] a) {
        return WordFactory.unsigned(ComputeObjectAddressNode.get(a, ReplacementsUtil.getArrayBaseOffset(INJECTED_METAACCESS, JavaKind.Int)));
    }

    
Idiom for making GraalHotSpotVMConfig a constant. /**
     * Idiom for making {@link GraalHotSpotVMConfig} a constant.
     */
    @Fold
    public static int objectAlignment(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.objectAlignment;
    }

    
Calls arrayAllocationSize(int, int, int, int) using an injected VM configuration object. /**
     * Calls {@link #arrayAllocationSize(int, int, int, int)} using an injected VM configuration
     * object.
     */
    public static int arrayAllocationSize(int length, int headerSize, int log2ElementSize) {
        return arrayAllocationSize(length, headerSize, log2ElementSize, objectAlignment(INJECTED_VMCONFIG));
    }

    
Computes the size of the memory chunk allocated for an array. This size accounts for the
array header size, body size and any padding after the last element to satisfy object
alignment requirements.
Params:
length – the number of elements in the array
headerSize – the size of the array header
log2ElementSize – log2 of the size of an element in the array
alignment – the object alignment
           requirement
Returns:
the size of the memory chunk/**
     * Computes the size of the memory chunk allocated for an array. This size accounts for the
     * array header size, body size and any padding after the last element to satisfy object
     * alignment requirements.
     *
     * @param length the number of elements in the array
     * @param headerSize the size of the array header
     * @param log2ElementSize log2 of the size of an element in the array
     * @param alignment the {@linkplain GraalHotSpotVMConfig#objectAlignment object alignment
     *            requirement}
     * @return the size of the memory chunk
     */
    public static int arrayAllocationSize(int length, int headerSize, int log2ElementSize, int alignment) {
        int size = (length << log2ElementSize) + headerSize + (alignment - 1);
        int mask = ~(alignment - 1);
        return size & mask;
    }

    @Fold
    public static int instanceHeaderSize(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.useCompressedClassPointers ? (2 * wordSize()) - 4 : 2 * wordSize();
    }

    @Fold
    public static byte dirtyCardValue(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.dirtyCardValue;
    }

    @Fold
    public static byte g1YoungCardValue(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.g1YoungCardValue;
    }

    @Fold
    public static int cardTableShift(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.cardtableShift;
    }

    @Fold
    public static int g1CardQueueIndexOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.g1CardQueueIndexOffset;
    }

    @Fold
    public static int g1CardQueueBufferOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.g1CardQueueBufferOffset;
    }

    @Fold
    public static int g1SATBQueueMarkingOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.g1SATBQueueMarkingOffset;
    }

    @Fold
    public static int g1SATBQueueIndexOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.g1SATBQueueIndexOffset;
    }

    @Fold
    public static int g1SATBQueueBufferOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.g1SATBQueueBufferOffset;
    }

    public static final LocationIdentity KLASS_SUPER_CHECK_OFFSET_LOCATION = NamedLocationIdentity.immutable("Klass::_super_check_offset");

    @Fold
    public static int superCheckOffsetOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.superCheckOffsetOffset;
    }

    public static final LocationIdentity SECONDARY_SUPER_CACHE_LOCATION = NamedLocationIdentity.mutable("SecondarySuperCache");

    @Fold
    public static int secondarySuperCacheOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.secondarySuperCacheOffset;
    }

    public static final LocationIdentity SECONDARY_SUPERS_LOCATION = NamedLocationIdentity.immutable("SecondarySupers");

    @Fold
    public static int secondarySupersOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.secondarySupersOffset;
    }

    public static final LocationIdentity DISPLACED_MARK_WORD_LOCATION = NamedLocationIdentity.mutable("DisplacedMarkWord");

    public static final LocationIdentity OBJECT_MONITOR_OWNER_LOCATION = NamedLocationIdentity.mutable("ObjectMonitor::_owner");

    public static final LocationIdentity OBJECT_MONITOR_RECURSION_LOCATION = NamedLocationIdentity.mutable("ObjectMonitor::_recursions");

    public static final LocationIdentity OBJECT_MONITOR_CXQ_LOCATION = NamedLocationIdentity.mutable("ObjectMonitor::_cxq");

    public static final LocationIdentity OBJECT_MONITOR_ENTRY_LIST_LOCATION = NamedLocationIdentity.mutable("ObjectMonitor::_EntryList");

    @Fold
    public static int lockDisplacedMarkOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.basicLockDisplacedHeaderOffset;
    }

    @Fold
    public static boolean useBiasedLocking(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.useBiasedLocking;
    }

    @Fold
    static int uninitializedIdentityHashCodeValue(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.uninitializedIdentityHashCodeValue;
    }

    @Fold
    static int identityHashCodeShift(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.identityHashCodeShift;
    }

    
Loads the hub of an object (without null checking it first).
/**
     * Loads the hub of an object (without null checking it first).
     */
    public static KlassPointer loadHub(Object object) {
        return loadHubIntrinsic(object);
    }

    public static Object verifyOop(Object object) {
        if (verifyOops(INJECTED_VMCONFIG)) {
            verifyOopStub(VERIFY_OOP, object);
        }
        return object;
    }

    @NodeIntrinsic(ForeignCallNode.class)
    private static native Object verifyOopStub(@ConstantNodeParameter ForeignCallDescriptor descriptor, Object object);

    public static Word loadWordFromObject(Object object, int offset) {
        ReplacementsUtil.staticAssert(offset != hubOffset(INJECTED_VMCONFIG), "Use loadHubIntrinsic instead of loadWordFromObject");
        return loadWordFromObjectIntrinsic(object, offset, LocationIdentity.any(), getWordKind());
    }

    public static Word loadWordFromObject(Object object, int offset, LocationIdentity identity) {
        ReplacementsUtil.staticAssert(offset != hubOffset(INJECTED_VMCONFIG), "Use loadHubIntrinsic instead of loadWordFromObject");
        return loadWordFromObjectIntrinsic(object, offset, identity, getWordKind());
    }

    public static KlassPointer loadKlassFromObject(Object object, int offset, LocationIdentity identity) {
        ReplacementsUtil.staticAssert(offset != hubOffset(INJECTED_VMCONFIG), "Use loadHubIntrinsic instead of loadWordFromObject");
        return loadKlassFromObjectIntrinsic(object, offset, identity, getWordKind());
    }

    
Reads the value of a given register.
Params:
register – a register which must not be available to the register allocator
Returns:
the value of register as a word/**
     * Reads the value of a given register.
     *
     * @param register a register which must not be available to the register allocator
     * @return the value of {@code register} as a word
     */
    public static Word registerAsWord(@ConstantNodeParameter Register register) {
        return registerAsWord(register, true, false);
    }

    @NodeIntrinsic(value = ReadRegisterNode.class)
    public static native Word registerAsWord(@ConstantNodeParameter Register register, @ConstantNodeParameter boolean directUse, @ConstantNodeParameter boolean incoming);

    @NodeIntrinsic(value = WriteRegisterNode.class)
    public static native void writeRegisterAsWord(@ConstantNodeParameter Register register, Word value);

    @NodeIntrinsic(value = RawLoadNode.class)
    private static native Word loadWordFromObjectIntrinsic(Object object, long offset, @ConstantNodeParameter LocationIdentity locationIdentity, @ConstantNodeParameter JavaKind wordKind);

    @NodeIntrinsic(value = RawLoadNode.class)
    private static native KlassPointer loadKlassFromObjectIntrinsic(Object object, long offset, @ConstantNodeParameter LocationIdentity locationIdentity, @ConstantNodeParameter JavaKind wordKind);

    @NodeIntrinsic(value = LoadHubNode.class)
    public static native KlassPointer loadHubIntrinsic(Object object);

    public static final LocationIdentity CLASS_STATE_LOCATION = NamedLocationIdentity.mutable("ClassState");

    @Fold
    public static int instanceKlassInitStateOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.instanceKlassInitStateOffset;
    }

    @Fold
    public static int instanceKlassStateFullyInitialized(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.instanceKlassStateFullyInitialized;
    }

    
Params:
hub – the hub of an InstanceKlass
Returns:
true is the InstanceKlass represented by hub is fully initialized/**
     *
     * @param hub the hub of an InstanceKlass
     * @return true is the InstanceKlass represented by hub is fully initialized
     */
    public static boolean isInstanceKlassFullyInitialized(KlassPointer hub) {
        return readInstanceKlassState(hub) == instanceKlassStateFullyInitialized(INJECTED_VMCONFIG);
    }

    private static byte readInstanceKlassState(KlassPointer hub) {
        return hub.readByte(instanceKlassInitStateOffset(INJECTED_VMCONFIG), CLASS_STATE_LOCATION);
    }

    public static final LocationIdentity KLASS_MODIFIER_FLAGS_LOCATION = NamedLocationIdentity.immutable("Klass::_modifier_flags");

    @Fold
    public static int klassModifierFlagsOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.klassModifierFlagsOffset;
    }

    public static final LocationIdentity CLASS_KLASS_LOCATION = new HotSpotOptimizingLocationIdentity("Class._klass") {
        @Override
        public ValueNode canonicalizeRead(ValueNode read, AddressNode location, ValueNode object, CanonicalizerTool tool) {
            return foldIndirection(read, object, CLASS_MIRROR_LOCATION);
        }
    };

    public static final LocationIdentity CLASS_ARRAY_KLASS_LOCATION = new HotSpotOptimizingLocationIdentity("Class._array_klass") {
        @Override
        public ValueNode canonicalizeRead(ValueNode read, AddressNode location, ValueNode object, CanonicalizerTool tool) {
            return foldIndirection(read, object, ARRAY_KLASS_COMPONENT_MIRROR);
        }
    };

    @Fold
    public static int arrayKlassOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.arrayKlassOffset;
    }

    public static final LocationIdentity CLASS_MIRROR_LOCATION = NamedLocationIdentity.immutable("Klass::_java_mirror");

    public static final LocationIdentity CLASS_MIRROR_HANDLE_LOCATION = NamedLocationIdentity.immutable("Klass::_java_mirror handle");

    @Fold
    public static int layoutHelperHeaderSizeShift(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.layoutHelperHeaderSizeShift;
    }

    @Fold
    public static int layoutHelperHeaderSizeMask(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.layoutHelperHeaderSizeMask;
    }

    @Fold
    public static int layoutHelperLog2ElementSizeShift(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.layoutHelperLog2ElementSizeShift;
    }

    @Fold
    public static int layoutHelperLog2ElementSizeMask(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.layoutHelperLog2ElementSizeMask;
    }

    @NodeIntrinsic(ForeignCallNode.class)
    public static native int identityHashCode(@ConstantNodeParameter ForeignCallDescriptor descriptor, Object object);

    @Fold
    public static long gcTotalCollectionsAddress(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.gcTotalCollectionsAddress();
    }

    @Fold
    public static long referentOffset(@InjectedParameter MetaAccessProvider metaAccessProvider) {
        return getFieldOffset(metaAccessProvider.lookupJavaType(Reference.class), "referent");
    }

    public static final LocationIdentity OBJ_ARRAY_KLASS_ELEMENT_KLASS_LOCATION = new HotSpotOptimizingLocationIdentity("ObjArrayKlass::_element_klass") {
        @Override
        public ValueNode canonicalizeRead(ValueNode read, AddressNode location, ValueNode object, CanonicalizerTool tool) {
            ValueNode javaObject = findReadHub(object);
            if (javaObject != null) {
                ResolvedJavaType type = StampTool.typeOrNull(javaObject);
                if (type != null && type.isArray()) {
                    ResolvedJavaType element = type.getComponentType();
                    if (element != null && !element.isPrimitive() && !element.getElementalType().isInterface()) {
                        Assumptions assumptions = object.graph().getAssumptions();
                        AssumptionResult<ResolvedJavaType> leafType = element.findLeafConcreteSubtype();
                        if (leafType != null && leafType.canRecordTo(assumptions)) {
                            leafType.recordTo(assumptions);
                            return ConstantNode.forConstant(read.stamp(NodeView.DEFAULT), tool.getConstantReflection().asObjectHub(leafType.getResult()), tool.getMetaAccess());
                        }
                    }
                }
            }
            return read;
        }
    };

    @Fold
    public static int arrayClassElementOffset(@InjectedParameter GraalHotSpotVMConfig config) {
        return config.arrayClassElementOffset;
    }

    public static final LocationIdentity PRIMARY_SUPERS_LOCATION = NamedLocationIdentity.immutable("PrimarySupers");

    public static final LocationIdentity METASPACE_ARRAY_LENGTH_LOCATION = NamedLocationIdentity.immutable("MetaspaceArrayLength");

    public static final LocationIdentity SECONDARY_SUPERS_ELEMENT_LOCATION = NamedLocationIdentity.immutable("SecondarySupersElement");
}