Benchmark: math pow vs bit shifting vs exponentiation operator

Tests:

pow
var x = Math.pow(2,15);
bit shifting
var y = 2 << 15;
exponentiation operator
var z = 2 ** 15

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
pow
bit shifting
exponentiation operator

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: 2 months ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/145.0.0.0 Safari/537.36

Browser/OS: Chrome 145 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
pow	115990616.0 Ops/sec
bit shifting	124541840.0 Ops/sec
exponentiation operator	120065824.0 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 its test cases.

**Benchmark Overview**

The provided benchmark measures the performance of three different ways to calculate `2^15`:

1. Using the `Math.pow()` function
2. Using left bit shifting (`<<`)
3. Using the exponentiation operator (`**`)

**Options Compared**

The benchmark compares the execution speed of these three approaches on various browsers, devices, and operating systems.

Pros and Cons:

* **Math.pow()**: This is a built-in JavaScript function that can be slow due to its implementation in C++ for performance reasons. However, it's also widely supported and provides a clear understanding of exponentiation.
* **Left Bit Shifting (`<<`)**: This approach is generally faster because it only requires shifting the bits of the number 2 and then adding 15, which is a simple operation. However, it may not be as intuitive or readable as other approaches.
* **Exponentiation Operator (`**`)**: This is a modern JavaScript feature introduced in ES6. It's also generally faster than `Math.pow()` because it can take advantage of the CPU's exponentiation instructions.

Other Considerations:

* The benchmark results are influenced by the device, browser, and operating system being used.
* Left bit shifting (`<<`) is more portable across different platforms compared to the other two approaches.
* Using the exponentiation operator (`**`)) might not be supported in older JavaScript engines or environments.

**Library Used**

In this benchmark, no specific libraries are mentioned. However, some browsers may have built-in optimizations that could affect the results.

**Special JS Features/Syntax**

The exponentiation operator (`**`) is a modern JavaScript feature introduced in ES6. It's widely supported in modern browsers and engines but might not be available or optimized in older environments.

**Alternative Approaches**

If you need to calculate `2^15` for other purposes, here are some alternative approaches:

* Using bit manipulation: `result = (1 << 30) - 1;`
* Using bitwise division: `result = Math.floor((1 << 15));`

Keep in mind that the choice of approach depends on your specific use case and performance requirements.

Related benchmarks:

math pow vs bit shifting vs exponentiation operator (version: 0)

Comparing performance of: pow vs bit shifting vs exponentiation operator

Created: 3 years ago by: Guest

Jump to the latest result

pow

bit shifting

exponentiation operator

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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