The Math.imul()
static method returns the result of the C-like 32-bit multiplication of the two parameters.
The Math.imul()
static method returns the result of the C-like 32-bit multiplication of the two parameters.
Math.imul(a, b)
The result of the C-like 32-bit multiplication of the given arguments.
Math.imul()
allows for 32-bit integer multiplication with C-like semantics. This feature is useful for projects like Emscripten.
Because imul()
is a static method of Math
, you always use it as Math.imul()
, rather than as a method of a Math
object you created (Math
is not a constructor).
If you use normal JavaScript floating point numbers in imul()
, you will experience a degrade in performance. This is because of the costly conversion from a floating point to an integer for multiplication, and then converting the multiplied integer back into a floating point. However, with asm.js, which allows JIT-optimizers to more confidently use integers in JavaScript, multiplying two numbers stored internally as integers (which is only possible with asm.js) with imul()
could be potentially more performant.
Math.imul(2, 4); // 8 Math.imul(-1, 8); // -8 Math.imul(-2, -2); // 4 Math.imul(0xffffffff, 5); // -5 Math.imul(0xfffffffe, 5); // -10
Specification |
---|
ECMAScript Language Specification # sec-math.imul |
Desktop | Mobile | Server | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | Deno | Node.js | ||
imul |
28 | 12 | 20 | 16 | 7 | 28 | 20 | 15 | 7 | 1.5 | 4.4 | 1.0 | 0.12.0 |
Math.imul
in core-js
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https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/imul