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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * published by the Free Software Foundation.  Oracle designates this
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * accompanied this code).
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package jdk.internal.invoke;

import java.lang.invoke.MethodType;
import java.util.Objects;

This class describes a native call, including arguments/return shuffle moves, PC entry point and
various other info which are relevant when the call will be intrinsified by C2.
/**
 * This class describes a native call, including arguments/return shuffle moves, PC entry point and
 * various other info which are relevant when the call will be intrinsified by C2.
 */
public class NativeEntryPoint {
    static {
        registerNatives();
    }

    private final long addr;

    private final int shadowSpace;

    // encoded as VMRegImpl*
    private final long[] argMoves;
    private final long[] returnMoves;

    private final boolean needTransition;
    private final MethodType methodType; // C2 sees erased version (byte -> int), so need this explicitly
    private final String name;

    private NativeEntryPoint(long addr, int shadowSpace, long[] argMoves, long[] returnMoves,
                     boolean needTransition, MethodType methodType, String name) {
        this.addr = addr;
        this.shadowSpace = shadowSpace;
        this.argMoves = Objects.requireNonNull(argMoves);
        this.returnMoves = Objects.requireNonNull(returnMoves);
        this.needTransition = needTransition;
        this.methodType = methodType;
        this.name = name;
    }

    public static NativeEntryPoint make(long addr, String name, ABIDescriptorProxy abi, VMStorageProxy[] argMoves, VMStorageProxy[] returnMoves,
                                        boolean needTransition, MethodType methodType) {
        if (returnMoves.length > 1) {
            throw new IllegalArgumentException("Multiple register return not supported");
        }

        return new NativeEntryPoint(
            addr, abi.shadowSpaceBytes(), encodeVMStorages(argMoves), encodeVMStorages(returnMoves), needTransition, methodType, name);
    }

    private static long[] encodeVMStorages(VMStorageProxy[] moves) {
        long[] out = new long[moves.length];
        for (int i = 0; i < moves.length; i++) {
            out[i] = vmStorageToVMReg(moves[i].type(), moves[i].index());
        }
        return out;
    }

    private static native long vmStorageToVMReg(int type, int index);

    public MethodType type() {
        return methodType;
    }

    private static native void registerNatives();
}