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package jdk.internal.foreign;

import jdk.incubator.foreign.CLinker;
import jdk.incubator.foreign.MemoryLayout;
import jdk.incubator.foreign.ValueLayout;

import java.nio.ByteOrder;

import static java.nio.ByteOrder.LITTLE_ENDIAN;
import static jdk.incubator.foreign.MemoryLayouts.ADDRESS;

public class PlatformLayouts {
    public static <Z extends MemoryLayout> Z pick(Z sysv, Z win64, Z aarch64) {
        return switch (CABI.current()) {
            case SysV -> sysv;
            case Win64 -> win64;
            case AArch64 -> aarch64;
        };
    }

    public static MemoryLayout asVarArg(MemoryLayout ml) {
        if (CABI.current() == CABI.Win64) {
            return Win64.asVarArg(ml);
        }
        return ml;
    }

    private static ValueLayout ofChar(ByteOrder order, long bitSize) {
        return MemoryLayout.ofValueBits(bitSize, order)
                .withAttribute(CLinker.TypeKind.ATTR_NAME, CLinker.TypeKind.CHAR);
    }

    private static ValueLayout ofShort(ByteOrder order, long bitSize) {
        return MemoryLayout.ofValueBits(bitSize, order)
                .withAttribute(CLinker.TypeKind.ATTR_NAME, CLinker.TypeKind.SHORT);
    }

    private static ValueLayout ofInt(ByteOrder order, long bitSize) {
        return MemoryLayout.ofValueBits(bitSize, order)
                .withAttribute(CLinker.TypeKind.ATTR_NAME, CLinker.TypeKind.INT);
    }

    private static ValueLayout ofLong(ByteOrder order, long bitSize) {
        return MemoryLayout.ofValueBits(bitSize, order)
                .withAttribute(CLinker.TypeKind.ATTR_NAME, CLinker.TypeKind.LONG);
    }

    private static ValueLayout ofLongLong(ByteOrder order, long bitSize) {
        return MemoryLayout.ofValueBits(bitSize, order)
                .withAttribute(CLinker.TypeKind.ATTR_NAME, CLinker.TypeKind.LONG_LONG);
    }

    private static ValueLayout ofFloat(ByteOrder order, long bitSize) {
        return MemoryLayout.ofValueBits(bitSize, order)
                .withAttribute(CLinker.TypeKind.ATTR_NAME, CLinker.TypeKind.FLOAT);
    }

    private static ValueLayout ofDouble(ByteOrder order, long bitSize) {
        return MemoryLayout.ofValueBits(bitSize, order)
                .withAttribute(CLinker.TypeKind.ATTR_NAME, CLinker.TypeKind.DOUBLE);
    }

    private static ValueLayout ofPointer(ByteOrder order, long bitSize) {
        return MemoryLayout.ofValueBits(bitSize, order)
                .withAttribute(CLinker.TypeKind.ATTR_NAME, CLinker.TypeKind.POINTER);
    }

    public static CLinker.TypeKind getKind(MemoryLayout layout) {
        return (CLinker.TypeKind)layout.attribute(CLinker.TypeKind.ATTR_NAME).orElseThrow(
            () -> new IllegalStateException("Unexpected value layout: could not determine ABI class"));
    }

    
This class defines layout constants modelling standard primitive types supported by the x64 SystemV ABI.
/**
     * This class defines layout constants modelling standard primitive types supported by the x64 SystemV ABI.
     */
    public static final class SysV {
        private SysV() {
            //just the one
        }

        
The char native type. /**
         * The {@code char} native type.
         */
        public static final ValueLayout C_CHAR = ofChar(LITTLE_ENDIAN, 8);

        
The short native type. /**
         * The {@code short} native type.
         */
        public static final ValueLayout C_SHORT = ofShort(LITTLE_ENDIAN, 16);

        
The int native type. /**
         * The {@code int} native type.
         */
        public static final ValueLayout C_INT = ofInt(LITTLE_ENDIAN, 32);

        
The long native type. /**
         * The {@code long} native type.
         */
        public static final ValueLayout C_LONG = ofLong(LITTLE_ENDIAN, 64);

        
The long long native type. /**
         * The {@code long long} native type.
         */
        public static final ValueLayout C_LONG_LONG = ofLongLong(LITTLE_ENDIAN, 64);

        
The float native type. /**
         * The {@code float} native type.
         */
        public static final ValueLayout C_FLOAT = ofFloat(LITTLE_ENDIAN, 32);

        
The double native type. /**
         * The {@code double} native type.
         */
        public static final ValueLayout C_DOUBLE = ofDouble(LITTLE_ENDIAN, 64);

        
The T* native type. /**
         * The {@code T*} native type.
         */
        public static final ValueLayout C_POINTER = ofPointer(LITTLE_ENDIAN, 64);

        
The va_list native type, as it is passed to a function. /**
         * The {@code va_list} native type, as it is passed to a function.
         */
        public static final MemoryLayout C_VA_LIST = SysV.C_POINTER;
    }

    
This class defines layout constants modelling standard primitive types supported by the x64 Windows ABI.
/**
     * This class defines layout constants modelling standard primitive types supported by the x64 Windows ABI.
     */
    public static final class Win64 {

        private Win64() {
            //just the one
        }

        
The name of the layout attribute (see MemoryLayout.attributes() used to mark variadic parameters. The attribute value must be a boolean. /**
         * The name of the layout attribute (see {@link MemoryLayout#attributes()} used to mark variadic parameters. The
         * attribute value must be a boolean.
         */
        public final static String VARARGS_ATTRIBUTE_NAME = "abi/windows/varargs";

        
The char native type. /**
         * The {@code char} native type.
         */
        public static final ValueLayout C_CHAR = ofChar(LITTLE_ENDIAN, 8);

        
The short native type. /**
         * The {@code short} native type.
         */
        public static final ValueLayout C_SHORT = ofShort(LITTLE_ENDIAN, 16);

        
The int native type. /**
         * The {@code int} native type.
         */
        public static final ValueLayout C_INT = ofInt(LITTLE_ENDIAN, 32);
        
The long native type. /**
         * The {@code long} native type.
         */
        public static final ValueLayout C_LONG = ofLong(LITTLE_ENDIAN, 32);

        
The long long native type. /**
         * The {@code long long} native type.
         */
        public static final ValueLayout C_LONG_LONG = ofLongLong(LITTLE_ENDIAN, 64);

        
The float native type. /**
         * The {@code float} native type.
         */
        public static final ValueLayout C_FLOAT = ofFloat(LITTLE_ENDIAN, 32);

        
The double native type. /**
         * The {@code double} native type.
         */
        public static final ValueLayout C_DOUBLE = ofDouble(LITTLE_ENDIAN, 64);

        
The T* native type. /**
         * The {@code T*} native type.
         */
        public static final ValueLayout C_POINTER = ofPointer(LITTLE_ENDIAN, 64);

        
The va_list native type, as it is passed to a function. /**
         * The {@code va_list} native type, as it is passed to a function.
         */
        public static final MemoryLayout C_VA_LIST = Win64.C_POINTER;

        
Return a new memory layout which describes a variadic parameter to be passed to a function.
Params:
layout – the original parameter layout.
Returns:
a layout which is the same as layout, except for the extra attribute VARARGS_ATTRIBUTE_NAME, which is set to true./**
         * Return a new memory layout which describes a variadic parameter to be passed to a function.
         * @param layout the original parameter layout.
         * @return a layout which is the same as {@code layout}, except for the extra attribute {@link #VARARGS_ATTRIBUTE_NAME},
         * which is set to {@code true}.
         */
        public static MemoryLayout asVarArg(MemoryLayout layout) {
            return layout.withAttribute(VARARGS_ATTRIBUTE_NAME, true);
        }
    }

    
This class defines layout constants modelling standard primitive types supported by the AArch64 ABI.
/**
     * This class defines layout constants modelling standard primitive types supported by the AArch64 ABI.
     */
    public static final class AArch64 {

        private AArch64() {
            //just the one
        }

        
The char native type. /**
         * The {@code char} native type.
         */
        public static final ValueLayout C_CHAR = ofChar(LITTLE_ENDIAN, 8);

        
The short native type. /**
         * The {@code short} native type.
         */
        public static final ValueLayout C_SHORT = ofShort(LITTLE_ENDIAN, 16);

        
The int native type. /**
         * The {@code int} native type.
         */
        public static final ValueLayout C_INT = ofInt(LITTLE_ENDIAN, 32);

        
The long native type. /**
         * The {@code long} native type.
         */
        public static final ValueLayout C_LONG = ofLong(LITTLE_ENDIAN, 64);

        
The long long native type. /**
         * The {@code long long} native type.
         */
        public static final ValueLayout C_LONG_LONG = ofLongLong(LITTLE_ENDIAN, 64);

        
The float native type. /**
         * The {@code float} native type.
         */
        public static final ValueLayout C_FLOAT = ofFloat(LITTLE_ENDIAN, 32);

        
The double native type. /**
         * The {@code double} native type.
         */
        public static final ValueLayout C_DOUBLE = ofDouble(LITTLE_ENDIAN, 64);

        
The T* native type. /**
         * The {@code T*} native type.
         */
        public static final ValueLayout C_POINTER = ofPointer(LITTLE_ENDIAN, 64);

        
The va_list native type, as it is passed to a function. /**
         * The {@code va_list} native type, as it is passed to a function.
         */
        public static final MemoryLayout C_VA_LIST = AArch64.C_POINTER;
    }
}