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 * (a) the Software, and
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 * (b) any piece of software and/or hardware listed in the lrgrwrks.txt file if
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 * Software and the Larger Work(s), and to sublicense the foregoing rights on
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package com.oracle.truffle.js.nodes.cast;

import com.oracle.truffle.api.dsl.Cached;
import com.oracle.truffle.api.dsl.Specialization;
import com.oracle.truffle.api.nodes.UnexpectedResultException;
import com.oracle.truffle.api.object.HiddenKey;
import com.oracle.truffle.api.profiles.BranchProfile;
import com.oracle.truffle.js.nodes.JSGuards;
import com.oracle.truffle.js.nodes.JavaScriptBaseNode;
import com.oracle.truffle.js.runtime.JSRuntime;
import com.oracle.truffle.js.runtime.Symbol;

Converts value to array index according to ES5 15.4 Array Objects.
/**
 * Converts value to array index according to ES5 15.4 Array Objects.
 */
public abstract class ToArrayIndexNode extends JavaScriptBaseNode {
    protected final boolean convertToPropertyKey;

    public abstract Object execute(Object operand);

    public abstract long executeLong(Object operand) throws UnexpectedResultException;

    @SuppressWarnings("static-method")
    public final boolean isResultArrayIndex(Object result) {
        return result instanceof Long;
    }

    protected ToArrayIndexNode(boolean convertToPropertyKey) {
        this.convertToPropertyKey = convertToPropertyKey;
    }

    public static ToArrayIndexNode create() {
        return ToArrayIndexNodeGen.create(true);
    }

    public static ToArrayIndexNode createNoToPropertyKey() {
        return ToArrayIndexNodeGen.create(false);
    }

    @Specialization(guards = "isIntArrayIndex(value)")
    protected static long doInteger(int value) {
        return value;
    }

    @Specialization(guards = "isLongArrayIndex(value)")
    protected static long doLong(long value) {
        return JSRuntime.castArrayIndex(value);
    }

    protected static boolean doubleIsIntIndex(double d) {
        return JSRuntime.doubleIsRepresentableAsInt(d) && d >= 0;
    }

    @Specialization(guards = "doubleIsIntIndex(value)")
    protected static long doDoubleAsIntIndex(double value) {
        return (long) value;
    }

    protected static boolean doubleIsUintIndex(double d) {
        return JSRuntime.doubleIsRepresentableAsUnsignedInt(d, true) && d >= 0 && d < 0xffff_ffffL;
    }

    @Specialization(guards = "doubleIsUintIndex(value)")
    protected static long doDoubleAsUintIndex(double value) {
        return JSRuntime.castArrayIndex(value);
    }

    @Specialization
    protected static Symbol doSymbol(Symbol value) {
        return value;
    }

    @Specialization
    protected static HiddenKey doHiddenKey(HiddenKey value) {
        assert false : value;
        return value;
    }

    @Specialization(guards = "isArrayIndexLengthInRange(index)")
    protected static Object convertFromString(String index,
                    @Cached("create()") BranchProfile startsWithDigitBranch,
                    @Cached("create()") BranchProfile isArrayIndexBranch,
                    @Cached("create()") BranchProfile needPassStringBranch) {
        if (JSRuntime.isAsciiDigit(index.charAt(0))) {
            startsWithDigitBranch.enter();
            long longValue = JSRuntime.parseArrayIndexRaw(index);
            if (JSRuntime.isArrayIndex(longValue)) {
                isArrayIndexBranch.enter();
                return JSRuntime.castArrayIndex(longValue);
            }
        }
        needPassStringBranch.enter();
        return index;
    }

    @Specialization(guards = "!isArrayIndexLengthInRange(index)")
    protected static Object convertFromStringNotInRange(String index) {
        return index;
    }

    protected static boolean notArrayIndex(Object o) {
        assert !(o instanceof HiddenKey);
        return (!(o instanceof Integer) || !JSGuards.isIntArrayIndex((int) o)) && (!(o instanceof Double) || !doubleIsUintIndex((double) o)) &&
                        (!(o instanceof Long) || !JSGuards.isLongArrayIndex((long) o)) && !(o instanceof String) && !(o instanceof Symbol);
    }

    @Specialization(guards = {"!convertToPropertyKey", "notArrayIndex(value)"})
    protected static Object doNonArrayIndex(Object value) {
        return value;
    }

    @Specialization(guards = {"convertToPropertyKey", "notArrayIndex(value)"})
    protected static Object doNonArrayIndex(Object value,
                    @Cached("create()") JSToPropertyKeyNode toPropertyKey) {
        return toPropertyKey.execute(value);
    }
}