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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * The Universal Permissive License (UPL), Version 1.0
 *
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 * person obtaining a copy of this software, associated documentation and/or
 * data (collectively the "Software"), free of charge and under any and all
 * copyright rights in the Software, and any and all patent rights owned or
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 * unmodified Software as contributed to or provided by such licensor, or (ii)
 * the Larger Works (as defined below), to deal in both
 *
 * (a) the Software, and
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 * (b) any piece of software and/or hardware listed in the lrgrwrks.txt file if
 * one is included with the Software each a "Larger Work" to which the Software
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 * without restriction, including without limitation the rights to copy, create
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 * Software and the Larger Work(s), and to sublicense the foregoing rights on
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 * This license is subject to the following condition:
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 * The above copyright notice and either this complete permission notice or at a
 * minimum a reference to the UPL must be included in all copies or substantial
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package com.oracle.truffle.js.nodes.cast;

import com.oracle.truffle.api.dsl.Cached;
import com.oracle.truffle.api.dsl.Cached.Shared;
import com.oracle.truffle.api.dsl.Specialization;
import com.oracle.truffle.api.profiles.BranchProfile;
import com.oracle.truffle.js.nodes.JavaScriptBaseNode;
import com.oracle.truffle.js.runtime.Errors;
import com.oracle.truffle.js.runtime.JSRuntime;
import com.oracle.truffle.js.runtime.SafeInteger;

Implementation of the abstract operation ToIndex(value) (ES7 7.1.17).
/**
 * Implementation of the abstract operation ToIndex(value) (ES7 7.1.17).
 */
public abstract class JSToIndexNode extends JavaScriptBaseNode {

    public static JSToIndexNode create() {
        return JSToIndexNodeGen.create();
    }

    public abstract long executeLong(Object value);

    @Specialization
    protected long doInt(int value,
                    @Cached @Shared("negativeIndexBranch") BranchProfile negativeIndexBranch) {
        if (value < 0) {
            negativeIndexBranch.enter();
            throw Errors.createRangeErrorIndexNegative(this);
        }
        return value;
    }

    @Specialization
    protected long doSafeInteger(SafeInteger value,
                    @Cached @Shared("negativeIndexBranch") BranchProfile negativeIndexBranch) {
        long longValue = value.longValue();
        if (longValue < 0) {
            negativeIndexBranch.enter();
            throw Errors.createRangeErrorIndexNegative(this);
        }
        return longValue;
    }

    @Specialization
    protected long doDouble(double value,
                    @Cached @Shared("negativeIndexBranch") BranchProfile negativeIndexBranch,
                    @Cached BranchProfile tooLargeIndexBranch) {
        long integerIndex = (long) value;
        if (integerIndex < 0) {
            negativeIndexBranch.enter();
            throw Errors.createRangeErrorIndexNegative(this);
        } else if (integerIndex > JSRuntime.MAX_SAFE_INTEGER_LONG) {
            tooLargeIndexBranch.enter();
            throw Errors.createRangeErrorIndexTooLarge(this);
        } else {
            return integerIndex;
        }
    }

    @Specialization(guards = "isUndefined(value)")
    protected static long doUndefined(@SuppressWarnings("unused") Object value) {
        return 0;
    }

    @Specialization
    protected static long doObject(Object value,
                    @Cached("create()") JSToNumberNode toNumberNode,
                    @Cached("create()") JSToIndexNode recursiveToIndexNode) {
        Number number = (Number) toNumberNode.execute(value);
        assert number instanceof Integer || number instanceof Double;
        return recursiveToIndexNode.executeLong(number);
    }
}