Benchmark: math pow vs bit shifting

Tests:

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

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
pow
bit shifting

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:147.0) Gecko/20100101 Firefox/147.0

Browser/OS: Firefox 147 on Windows

View result in a separate tab

Test name	Executions per second
pow	1645249280.0 Ops/sec
bit shifting	1464240256.0 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 JSON and explain what's being tested, compared, and evaluated in this JavaScript microbenchmark.

**Benchmark Definition**

The provided `Benchmark Definition` json is empty, which means that the benchmark script needs to be defined manually. Typically, it would contain a JavaScript function or expression that performs some mathematical operation, such as calculating powers or performing bitwise shifts.

**Individual Test Cases**

There are two test cases:

1. **"pow"**: This test case uses the `Math.pow()` function to calculate 2 raised to the power of 15.
2. **"bit shifting"**: This test case uses bitwise shift (<<) operation to achieve the same result as in the "pow" case, but using bit manipulation instead of exponentiation.

**Options Compared**

The two options being compared are:

* `Math.pow(2, 15)` (exponentiation)
* `2 << 15` (bitwise shift)

Both methods produce the same result, which is a large integer value. However, they differ in their approach and performance characteristics.

**Pros and Cons of Each Approach**

**Exponentiation (`Math.pow()`)**

Pros:

* More intuitive and readable for developers familiar with exponentiation.
* Often used in mathematical formulas and equations.

Cons:

* Generally slower than bitwise shift due to the overhead of function calls and intermediate results.

**Bitwise Shift**

Pros:

* Faster and more efficient, as it only requires a single operation.
* Can be optimized by the compiler or interpreter for specific CPU architectures.

Cons:

* May require additional understanding of binary arithmetic and bit manipulation.
* Less intuitive for developers without experience in this area.

**Other Considerations**

* **Library Usage**: None of these test cases use any external libraries. However, if a library were used to simplify the exponentiation operation (e.g., using `Math.exp()` or a third-party library), it could affect the benchmark results.
* **Special JS Features or Syntax**: There are no special JavaScript features or syntax involved in this benchmark.

**Alternatives**

If you want to explore other options, here are some alternative approaches:

* Using `Math.pow()` with a higher exponent value (e.g., 2^32) might provide more insight into the performance differences between exponentiation and bitwise shift.
* Implementing custom exponentiation algorithms using bitwise operations or other mathematical techniques could provide further benchmarking insights.

Keep in mind that these alternatives would require significant modifications to the benchmark script, but they could offer additional insights into the performance characteristics of different mathematical operations.

Related benchmarks:

math pow vs bit shifting (version: 0)

Comparing performance of: pow vs bit shifting

Created: 5 years ago by: Guest

Jump to the latest result

pow

bit shifting

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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