Function js_sys::Atomics::xor

pub fn xor(
    typed_array: &JsValue,
    index: u32,
    value: i32
) -> Result<i32, JsValue>

The static Atomics.xor() method computes a bitwise XOR with a given value at a given position in the array, and returns the old value at that position. This atomic operation guarantees that no other write happens until the modified value is written back.

You should use xor_bigint to operate on a BigInt64Array or a BigUint64Array.

MDN documentation