Benchmark: Test power of 2 - MeasureThat.net

Tests:

var x = 2**21
var x = 2**21
var y = Math.pow(2, 21)
var y = Math.pow(2, 21)
var z = 1 << 21
var z = 1 << 21

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
var x = 2**21
var y = Math.pow(2, 21)
var z = 1 << 21

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):

LLMs can make mistakes. Check important info.

**Overview of the Benchmark**

The provided JSON represents a JavaScript microbenchmarking test case. The goal is to measure the performance of different approaches for exponentiation operations.

**Exponentiation Operations: What's being tested?**

There are three main exponentiation operations being compared:

1. `2**21` (shorthand exponentiation)
2. `Math.pow(2, 21)` (standardized power function from JavaScript's Math library)
3. `1 << 21` (bitwise left shift)

These operations are essentially equivalent, but they have different performance characteristics.

**Approach Comparison**

Here's a brief overview of each approach and their pros/cons:

1. **Shorthand Exponentiation (`2**21`)**
	* Pros: Simple and concise syntax.
	* Cons: May not be optimized for performance by modern JavaScript engines.
	* Notes: This is the most straightforward way to write exponentiation, but it's also likely to be slower than other methods due to its simplicity.
2. **Standardized Power Function (`Math.pow(2, 21)`)**
	* Pros: Part of the standard library, so optimized by JavaScript engines.
	* Cons: May have a slight overhead due to function call and lookup.
	* Notes: This approach uses the `Math.pow()` function, which is likely to be optimized for performance. However, it requires a function call, which might add some overhead compared to the other methods.
3. **Bitwise Left Shift (`1 << 21`)**
	* Pros: Fastest method in terms of CPU cycles, since it only involves bit manipulation.
	* Cons: Requires knowledge of bitwise operations and may be less readable.
	* Notes: This approach uses the bitwise left shift operator to calculate the exponentiation. It's a common technique for fast exponentiation and is likely to be the fastest method.

**Library Usage**

The `Math.pow()` function from JavaScript's Math library is used in one of the benchmark test cases (`var y = Math.pow(2, 21)`). The Math library provides various mathematical functions, including power calculation. This approach leverages the optimized implementation within the library.

**Special JS Features**

There are no special JavaScript features or syntaxes being tested in this benchmark (e.g., async/await, arrow functions, etc.).

**Other Alternatives**

For fast exponentiation, other approaches exist besides the ones mentioned above:

* **Muller's Algorithm**: A fast and efficient algorithm for exponentiation by squaring.
* **Exponentiation by Squaring**: An optimization technique that reduces the number of multiplications required to calculate `x^n` by using repeated squaring.

Keep in mind that these alternative approaches are more complex and might require additional setup or modifications to work with your specific use case.

Latest run results:

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

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/105.0.0.0 Safari/537.36

Browser/OS: Chrome 105 on Mac OS X 10.15.7

View result in a separate tab

Test name	Executions per second
var x = 2**21	683558656.0 Ops/sec
var y = Math.pow(2, 21)	5481911.0 Ops/sec
var z = 1 << 21	741881856.0 Ops/sec

Related benchmarks:

Test power of 2 (version: 0)

Comparing performance of: var x = 2**21 vs var y = Math.pow(2, 21) vs var z = 1 << 21

Created: 2 years ago by: Guest

Jump to the latest result

var x = 2**21

var y = Math.pow(2, 21)

var z = 1 << 21

Suite status: <idle, ready to run>

Experimental features:

Fastest: N/A

Slowest: N/A

Autogenerated LLM Summary (model llama3.2:3b, generated 26 days ago):