/* * Copyright (c) 2020-2021, Andreas Kling * Copyright (c) 2020-2021, Linus Groh * Copyright (c) 2020-2022, Idan Horowitz * * SPDX-License-Identifier: BSD-2-Clause */ #pragma once #include #include #include namespace JS { struct ValueTraits : public Traits { static unsigned hash(Value value) { VERIFY(!value.is_empty()); if (value.is_string()) { // FIXME: Propagate this error. return value.as_string().deprecated_string().release_value().hash(); } if (value.is_bigint()) return value.as_bigint().big_integer().hash(); if (value.is_negative_zero()) value = Value(0); // In the IEEE 754 standard a NaN value is encoded as any value from 0x7ff0000000000001 to 0x7fffffffffffffff, // with the least significant bits (referred to as the 'payload') carrying some kind of diagnostic information // indicating the source of the NaN. Since ECMA262 does not differentiate between different kinds of NaN values, // Sets and Maps must not differentiate between them either. // This is achieved by replacing any NaN value by a canonical qNaN. else if (value.is_nan()) value = js_nan(); return u64_hash(value.encoded()); // FIXME: Is this the best way to hash pointers, doubles & ints? } static bool equals(const Value a, const Value b) { return same_value_zero(a, b); } }; }