JS Atomics.xor()
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.
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Syntax
Atomics.xor(typedArray, index, value)
Parameters
typedArray
A shared integer typed array. One of Int8Array, Uint8Array, Int16Array, Uint16Array, Int32Array, or Uint32Array.
index
The position in the typedArray to compute the bitwise XOR.
value
The number to compute the bitwise XOR with.
Return value
The old value at the given position (typedArray[index]).
Exceptions
- Throws a
TypeError, iftypedArrayis not one of the allowed integer types. - Throws a
TypeError, iftypedArrayis not a shared typed array type. - Throws a
RangeError, ifindexis out of bounds in thetypedArray.
Description
The bitwise XOR operation yields 1, if a and b are different. The truth table for the XOR operation is:
a |
b |
a ^ b |
|---|---|---|
| 0 | 0 | 0 |
| 0 | 1 | 1 |
| 1 | 0 | 1 |
| 1 | 1 | 0 |
For example, a bitwise XOR of 5 & 1 results in 0100 which is 4 in decimal.
5 0101
1 0001
----
4 0100
Examples
var sab = new SharedArrayBuffer(1024);
var ta = new Uint8Array(sab);
ta[0] = 5;
Atomics.xor(ta, 0, 1); // returns 5, the old value
Atomics.load(ta, 0); // 4
Specifications
| Specification | Status | Comment |
|---|---|---|
| ECMAScript Latest Draft (ECMA-262)The definition of ‘Atomics.xor’ in that specification. | Draft | Initial definition in ES2017. |
