Benchmark: 2's math pow vs shift vs exp

Tests:

pow
var x = Math.pow(2,18);
shift
var y = 1 << 18
Exponentiation
var y = 2 ** 18

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
pow
shift
Exponentiation

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 8 months ago)

User agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/139.0.0.0 Safari/537.36

Browser/OS: Chrome 139 on Linux

View result in a separate tab

Test name	Executions per second
pow	141218080.0 Ops/sec
shift	145692880.0 Ops/sec
Exponentiation	136951808.0 Ops/sec

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):

LLMs can make mistakes. Check important info.

Let's break down the provided benchmark and explain what's being tested, compared, and their pros/cons.

**Benchmark Overview**

The benchmark measures the performance of three different methods to calculate the power of 2:

1. `Math.pow(2,18)`
2. `1 << 18` (shift operation)
3. `2 ** 18` (exponentiation)

These three operations are equivalent and should produce the same result.

**Comparison**

The benchmark compares the performance of these three methods across different browsers on mobile devices.

**Pros/Cons of each approach:**

1. `Math.pow(2,18)`:
	* Pros: Simple and straightforward.
	* Cons: May be slower due to the overhead of function calls and the need for a dedicated math library.
2. `1 << 18` (shift operation):
	* Pros: Fast and efficient, as it's a bitwise shift operation that can be optimized by most CPUs.
	* Cons: May not work correctly if the result overflows the maximum value representable by an integer.
3. `2 ** 18` (exponentiation):
	* Pros: Can be faster than `Math.pow()` due to the use of a specialized exponentiation algorithm in some browsers.
	* Cons: May not be available in all browsers or environments, and may require additional calculations.

**Library/Functionality Used**

The benchmark uses the following libraries/functions:

1. `Math.pow()`: a built-in JavaScript function for calculating powers.
2. Bitwise shift operators (`<<`): native JavaScript operators for shifting bits.
3. Exponentiation operator (`**`): introduced in ECMAScript 2016 (ES6) as a shorthand for exponentiation.

**Special JS Feature/Syntax**

The benchmark uses the exponentiation operator (`**`) which was introduced in ES6. If your browser does not support ES6, this benchmark may not work correctly.

**Other Alternatives**

Some alternative methods to calculate powers could be used, such as:

1. Using a loop: `for (var i = 0; i < 18; i++) { x *= 2; }`
2. Using the `Math.log()` and `Math.exp()` functions: `x = Math.exp(Math.log(2) * 18)`
3. Using a custom implementation of exponentiation, such as using binary exponentiation.

It's worth noting that these alternatives may not be as efficient or accurate as the three methods being compared in this benchmark.

Related benchmarks:

2's math pow vs shift vs exp (version: 0)

Comparing performance of: pow vs shift vs Exponentiation

Created: 5 years ago by: Guest

Jump to the latest result

pow

shift

Exponentiation

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated one year ago):