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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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package org.graalvm.compiler.truffle.test.jdk11;

import java.lang.invoke.MethodHandles;
import java.lang.invoke.VarHandle;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;

import org.graalvm.compiler.truffle.test.PartialEvaluationTest;
import org.graalvm.compiler.truffle.test.nodes.AbstractTestNode;
import org.graalvm.compiler.truffle.test.nodes.RootTestNode;
import org.junit.Assert;
import org.junit.Test;

import com.oracle.truffle.api.RootCallTarget;
import com.oracle.truffle.api.Truffle;
import com.oracle.truffle.api.frame.FrameDescriptor;
import com.oracle.truffle.api.frame.VirtualFrame;
import com.oracle.truffle.api.nodes.RootNode;

public class VarHandlePartialEvaluationTest extends PartialEvaluationTest {

    static final VarHandle byteArrayHandle = MethodHandles.byteArrayViewVarHandle(int[].class, ByteOrder.nativeOrder());
    static final VarHandle byteBufferHandle = MethodHandles.byteBufferViewVarHandle(int[].class, ByteOrder.nativeOrder());

    
Tests partial evaluation of a byte array view VarHandle.get. /**
     * Tests partial evaluation of a byte array view {@link VarHandle#get}.
     */
    @Test
    public void byteArrayHandleGet() {
        byte[] array = ByteBuffer.allocate(42).order(ByteOrder.nativeOrder()).putInt(0, 42).array();
        testCommon(new VarHandleTestNode(true, false), "byteArrayHandleGetInt", array, 0);
    }

    
Tests partial evaluation of a byte array view VarHandle.set. /**
     * Tests partial evaluation of a byte array view {@link VarHandle#set}.
     */
    @Test
    public void byteArrayHandleSet() {
        byte[] array = ByteBuffer.allocate(42).order(ByteOrder.nativeOrder()).putInt(0, 42).array();
        testCommon(new VarHandleTestNode(true, true), "byteArrayHandleSetInt", array, 0, 42);
    }

    
Tests partial evaluation of a byte buffer view VarHandle.get. /**
     * Tests partial evaluation of a byte buffer view {@link VarHandle#get}.
     */
    @Test
    public void byteBufferHandleGet() {
        ByteBuffer byteBuffer = ByteBuffer.allocate(42).order(ByteOrder.nativeOrder()).putInt(0, 42);
        testCommon(new VarHandleTestNode(false, false), "byteBufferHandleGetInt", byteBuffer, 0);
    }

    
Tests partial evaluation of a byte buffer view VarHandle.set. /**
     * Tests partial evaluation of a byte buffer view {@link VarHandle#set}.
     */
    @Test
    public void byteBufferHandleSet() {
        ByteBuffer byteBuffer = ByteBuffer.allocate(42).order(ByteOrder.nativeOrder()).putInt(0, 42);
        testCommon(new VarHandleTestNode(false, true), "byteArrayHandleSetInt", byteBuffer, 0, 42);
    }

    private void testCommon(AbstractTestNode testNode, String testName, Object... args) {
        FrameDescriptor fd = new FrameDescriptor();
        RootNode rootNode = new RootTestNode(fd, testName, testNode);
        RootCallTarget callTarget = Truffle.getRuntime().createCallTarget(rootNode);
        Assert.assertEquals(42, callTarget.call(args));
        assertPartialEvalNoInvokes(callTarget, args);
    }

    static final class VarHandleTestNode extends AbstractTestNode {
        private final boolean isArray;
        private final boolean set;

        VarHandleTestNode(boolean isArray, boolean set) {
            this.isArray = isArray;
            this.set = set;
        }

        @Override
        public int execute(VirtualFrame frame) {
            Object buf = frame.getArguments()[0];
            int idx = (int) frame.getArguments()[1];
            if (set) {
                int val = (int) frame.getArguments()[2];
                if (isArray) {
                    byteArrayHandle.set((byte[]) buf, idx, val);
                } else {
                    byteBufferHandle.set((ByteBuffer) buf, idx, val);
                }
                return val;
            } else {
                if (isArray) {
                    return (int) byteArrayHandle.get((byte[]) buf, idx);
                } else {
                    return (int) byteBufferHandle.get((ByteBuffer) buf, idx);
                }
            }
        }
    }
}