/*

 * Copyright (c) 2014, 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.

 */

//JaCoCo Exclude

package org.graalvm.compiler.replacements.arraycopy;

import static org.graalvm.compiler.nodeinfo.InputType.Memory;

import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_UNKNOWN;

import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_UNKNOWN;

import org.graalvm.compiler.core.common.spi.ForeignCallDescriptor;

import org.graalvm.compiler.core.common.type.Stamp;

import org.graalvm.compiler.core.common.type.StampFactory;

import org.graalvm.compiler.graph.Node;

import org.graalvm.compiler.graph.NodeClass;

import org.graalvm.compiler.graph.spi.Canonicalizable;

import org.graalvm.compiler.graph.spi.CanonicalizerTool;

import org.graalvm.compiler.nodeinfo.InputType;

import org.graalvm.compiler.nodeinfo.NodeInfo;

import org.graalvm.compiler.nodes.ConstantNode;

import org.graalvm.compiler.nodes.FixedWithNextNode;

import org.graalvm.compiler.nodes.GetObjectAddressNode;

import org.graalvm.compiler.nodes.NamedLocationIdentity;

import org.graalvm.compiler.nodes.NodeView;

import org.graalvm.compiler.nodes.StructuredGraph;

import org.graalvm.compiler.nodes.ValueNode;

import org.graalvm.compiler.nodes.calc.AddNode;

import org.graalvm.compiler.nodes.calc.IntegerConvertNode;

import org.graalvm.compiler.nodes.calc.LeftShiftNode;

import org.graalvm.compiler.nodes.extended.ForeignCallNode;

import org.graalvm.compiler.nodes.memory.AbstractMemoryCheckpoint;

import org.graalvm.compiler.nodes.memory.MemoryAccess;

import org.graalvm.compiler.nodes.memory.MemoryCheckpoint;

import org.graalvm.compiler.nodes.memory.MemoryNode;

import org.graalvm.compiler.nodes.memory.address.OffsetAddressNode;

import org.graalvm.compiler.nodes.spi.Lowerable;

import org.graalvm.compiler.nodes.spi.LoweringTool;

import org.graalvm.compiler.word.WordTypes;

import jdk.internal.vm.compiler.word.LocationIdentity;

import jdk.vm.ci.code.CodeUtil;

import jdk.vm.ci.meta.JavaConstant;

import jdk.vm.ci.meta.JavaKind;

import jdk.vm.ci.meta.MetaAccessProvider;

import jdk.vm.ci.meta.PrimitiveConstant;

@NodeInfo(allowedUsageTypes = {Memory}, cycles = CYCLES_UNKNOWN, size = SIZE_UNKNOWN)

public final class ArrayCopyCallNode extends AbstractMemoryCheckpoint implements Lowerable, MemoryCheckpoint.Single, MemoryAccess, Canonicalizable {

    public static final NodeClass<ArrayCopyCallNode> TYPE = NodeClass.create(ArrayCopyCallNode.class);

    @Input protected ValueNode src;

    @Input protected ValueNode srcPos;

    @Input protected ValueNode dest;

    @Input protected ValueNode destPos;

    @Input protected ValueNode length;

    @OptionalInput(Memory) MemoryNode lastLocationAccess;

    private final JavaKind elementKind;

    private final LocationIdentity locationIdentity;

    private final ArrayCopyForeignCalls foreignCalls;

    private final JavaKind wordJavaKind;

    private final int heapWordSize;

    /**

     * Aligned means that the offset of the copy is heap word aligned.

     */

    private boolean aligned;

    private boolean disjoint;

    private boolean uninitialized;

    public ArrayCopyCallNode(@InjectedNodeParameter ArrayCopyForeignCalls foreignCalls, @InjectedNodeParameter WordTypes wordTypes,

                    ValueNode src, ValueNode srcPos, ValueNode dest, ValueNode destPos,

                    ValueNode length, JavaKind elementKind, boolean aligned, boolean disjoint, boolean uninitialized, int heapWordSize) {

        this(foreignCalls, wordTypes, src, srcPos, dest, destPos, length, elementKind, null, aligned, disjoint, uninitialized, heapWordSize);

    }

    protected ArrayCopyCallNode(@InjectedNodeParameter ArrayCopyForeignCalls foreignCalls, @InjectedNodeParameter WordTypes wordTypes,

                    ValueNode src, ValueNode srcPos, ValueNode dest,

                    ValueNode destPos, ValueNode length, JavaKind elementKind,

                    LocationIdentity locationIdentity, boolean aligned, boolean disjoint, boolean uninitialized, int heapWordSize) {

        super(TYPE, StampFactory.forVoid());

        assert elementKind != null;

        this.src = src;

        this.srcPos = srcPos;

        this.dest = dest;

        this.destPos = destPos;

        this.length = length;

        this.elementKind = elementKind;

        this.locationIdentity = (locationIdentity != null ? locationIdentity : NamedLocationIdentity.getArrayLocation(elementKind));

        this.aligned = aligned;

        this.disjoint = disjoint;

        this.uninitialized = uninitialized;

        this.foreignCalls = foreignCalls;

        this.wordJavaKind = wordTypes.getWordKind();

        this.heapWordSize = heapWordSize;

    }

    public ValueNode getSource() {

        return src;

    }

    public ValueNode getSourcePosition() {

        return srcPos;

    }

    public ValueNode getDestination() {

        return dest;

    }

    public ValueNode getDestinationPosition() {

        return destPos;

    }

    public ValueNode getLength() {

        return length;

    }

    public JavaKind getElementKind() {

        return elementKind;

    }

    private ValueNode computeBase(LoweringTool tool, ValueNode base, ValueNode pos) {

        FixedWithNextNode basePtr = graph().add(new GetObjectAddressNode(base));

        graph().addBeforeFixed(this, basePtr);

        Stamp wordStamp = StampFactory.forKind(wordJavaKind);

        ValueNode wordPos = IntegerConvertNode.convert(pos, wordStamp, graph(), NodeView.DEFAULT);

        int shift = CodeUtil.log2(tool.getMetaAccess().getArrayIndexScale(elementKind));

        ValueNode scaledIndex = graph().unique(new LeftShiftNode(wordPos, ConstantNode.forInt(shift, graph())));

        ValueNode offset = graph().unique(new AddNode(scaledIndex, ConstantNode.forIntegerStamp(wordStamp, tool.getMetaAccess().getArrayBaseOffset(elementKind), graph())));

        return graph().unique(new OffsetAddressNode(basePtr, offset));

    }

    @Override

    public void lower(LoweringTool tool) {

        if (graph().getGuardsStage().areFrameStatesAtDeopts()) {

            updateAlignedDisjoint(tool.getMetaAccess());

            ForeignCallDescriptor desc = foreignCalls.lookupArraycopyDescriptor(elementKind, isAligned(), isDisjoint(), isUninitialized(),

                            locationIdentity.equals(LocationIdentity.any()));

            StructuredGraph graph = graph();

            ValueNode srcAddr = computeBase(tool, getSource(), getSourcePosition());

            ValueNode destAddr = computeBase(tool, getDestination(), getDestinationPosition());

            ValueNode len = getLength();

            if (len.stamp(NodeView.DEFAULT).getStackKind() != JavaKind.Long) {

                len = IntegerConvertNode.convert(len, StampFactory.forKind(JavaKind.Long), graph(), NodeView.DEFAULT);

            }

            ForeignCallNode call = graph.add(new ForeignCallNode(foreignCalls, desc, srcAddr, destAddr, len));

            call.setStateAfter(stateAfter());

            graph.replaceFixedWithFixed(this, call);

        }

    }

    @Override

    public MemoryNode getLastLocationAccess() {

        return lastLocationAccess;

    }

    @Override

    public void setLastLocationAccess(MemoryNode lla) {

        updateUsagesInterface(lastLocationAccess, lla);

        lastLocationAccess = lla;

    }

    @Override

    public LocationIdentity getLocationIdentity() {

        return locationIdentity;

    }

    @NodeIntrinsic(hasSideEffect = true)

    private static native void arraycopy(Object src, int srcPos, Object dest, int destPos, int length, @ConstantNodeParameter JavaKind elementKind, @ConstantNodeParameter boolean aligned,

                    @ConstantNodeParameter boolean disjoint, @ConstantNodeParameter boolean uninitialized, @ConstantNodeParameter int heapWordSize);

    @NodeIntrinsic(hasSideEffect = true)

    private static native void arraycopy(Object src, int srcPos, Object dest, int destPos, int length, @ConstantNodeParameter JavaKind elementKind,

                    @ConstantNodeParameter LocationIdentity locationIdentity, @ConstantNodeParameter boolean aligned, @ConstantNodeParameter boolean disjoint,

                    @ConstantNodeParameter boolean uninitialized, @ConstantNodeParameter int heapWordSize);

    public static void arraycopyObjectKillsAny(Object src, int srcPos, Object dest, int destPos, int length, @ConstantNodeParameter int heapWordSize) {

        arraycopy(src, srcPos, dest, destPos, length, JavaKind.Object, LocationIdentity.any(), false, false, false, heapWordSize);

    }

    public static void arraycopy(Object src, int srcPos, Object dest, int destPos, int length, @ConstantNodeParameter JavaKind elementKind, @ConstantNodeParameter LocationIdentity locationIdentity,

                    @ConstantNodeParameter int heapWordSize) {

        arraycopy(src, srcPos, dest, destPos, length, elementKind, locationIdentity, false, false, false, heapWordSize);

    }

    public static void disjointArraycopy(Object src, int srcPos, Object dest, int destPos, int length, @ConstantNodeParameter JavaKind elementKind, @ConstantNodeParameter int heapWordSize) {

        arraycopy(src, srcPos, dest, destPos, length, elementKind, false, true, false, heapWordSize);

    }

    public static void disjointArraycopyKillsAny(Object src, int srcPos, Object dest, int destPos, int length, @ConstantNodeParameter JavaKind elementKind, @ConstantNodeParameter int heapWordSize) {

        arraycopy(src, srcPos, dest, destPos, length, elementKind, LocationIdentity.any(), false, true, false, heapWordSize);

    }

    public static void disjointUninitializedArraycopy(Object src, int srcPos, Object dest, int destPos, int length, @ConstantNodeParameter JavaKind elementKind,

                    @ConstantNodeParameter int heapWordSize) {

        arraycopy(src, srcPos, dest, destPos, length, elementKind, false, true, true, heapWordSize);

    }

    public boolean isAligned() {

        return aligned;

    }

    public boolean isDisjoint() {

        return disjoint;

    }

    public boolean isUninitialized() {

        return uninitialized;

    }

    boolean isHeapWordAligned(MetaAccessProvider metaAccess, JavaConstant value, JavaKind kind) {

        return (metaAccess.getArrayBaseOffset(kind) + (long) value.asInt() * metaAccess.getArrayIndexScale(kind)) % heapWordSize == 0;

    }

    public void updateAlignedDisjoint(MetaAccessProvider metaAccess) {

        JavaKind componentKind = elementKind;

        if (srcPos == destPos) {

            // Can treat as disjoint

            disjoint = true;

        }

        PrimitiveConstant constantSrc = (PrimitiveConstant) srcPos.stamp(NodeView.DEFAULT).asConstant();

        PrimitiveConstant constantDst = (PrimitiveConstant) destPos.stamp(NodeView.DEFAULT).asConstant();

        if (constantSrc != null && constantDst != null) {

            if (!aligned) {

                aligned = isHeapWordAligned(metaAccess, constantSrc, componentKind) && isHeapWordAligned(metaAccess, constantDst, componentKind);

            }

            if (constantSrc.asInt() >= constantDst.asInt()) {

                // low to high copy so treat as disjoint

                disjoint = true;

            }

        }

    }

    @Override

    public Node canonical(CanonicalizerTool tool) {

        if (getLength().isConstant() && getLength().asConstant().isDefaultForKind()) {

            if (lastLocationAccess != null) {

                replaceAtUsages(InputType.Memory, lastLocationAccess.asNode());

            }

            return null;

        }

        return this;

    }

}