/*

 * Copyright (c) 2012, 2019, 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.LoadHubOrNullNode;

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.

 */

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.

         *

         * @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;

        }

    }

    @Fold

    public static ResolvedJavaType methodHolderClass(@InjectedParameter IntrinsicContext context) {

        return context.getOriginalMethod().getDeclaringClass();

    }

    @Fold

    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);

        }

    }

    @Fold

    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 + " in type " + type);

    }

    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;

    }

    /**

     * @see GraalHotSpotVMConfig#doingUnsafeAccessOffset

     */

    @Fold

    public static int doingUnsafeAccessOffset(@InjectedParameter GraalHotSpotVMConfig config) {

        return config.doingUnsafeAccessOffset;

    }

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

    /**

     * @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 GraalHotSpotVMConfig#pendingExceptionOffset

     */

    @Fold

    static int threadPendingExceptionOffset(@InjectedParameter GraalHotSpotVMConfig config) {

        return config.pendingExceptionOffset;

    }

    /**

     * @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 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.

     *

     * @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.

     *

     * @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 {@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) {