Benchmark: Bool generation from uint32

Script Preparation code:

function getRandomUint32(min, max) {
    return Math.floor(Math.random() * (max - min) + min);
}

Tests:

Compare to half of max int
for(let i = 0; i < 100; i++) { const z = getRandomUint32(0, 2 ** 32) < 2_147_483_648; }
Mod even/odd
for(let i = 0; i < 100; i++) { const z = getRandomUint32(0, 2 ** 32) % 2 === 0; }
Bitwise even/odd
for(let i = 0; i < 100; i++) { const z = getRandomUint32(0, 2 ** 32) & 1 === 1; }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Compare to half of max int
Mod even/odd
Bitwise even/odd

Fastest: N/A

Slowest: N/A

Latest run results:

Run details: (Test run date: one year ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:128.0) Gecko/20100101 Firefox/128.0

Browser/OS: Firefox 128 on Windows

View result in a separate tab

Test name	Executions per second
Compare to half of max int	21006774.0 Ops/sec
Mod even/odd	20871864.0 Ops/sec
Bitwise even/odd	20994424.0 Ops/sec

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

LLMs can make mistakes. Check important info.

**Overview of the Benchmark**

The provided JSON represents a JavaScript microbenchmark that tests the performance of different approaches for generating boolean values from 32-bit unsigned integers. The benchmark consists of three test cases:

1. Comparing a generated value to half of the maximum integer.
2. Checking if a generated value is even (remainder when divided by 2 is 0).
3. Using bitwise operations to check if a generated value is odd (least significant bit is 1).

**Benchmark Preparation Code**

The `getRandomUint32` function is used to generate random 32-bit unsigned integers. This function uses the `Math.random()` method to generate a random number, multiplies it by `(max - min) + 1`, and then adds `min` to shift the range.

**Options Compared**

In each test case, the options being compared are:

* A direct comparison using `<`
* A modulo operation with `%`
* A bitwise AND operation with `&`

These options differ in their implementation and potential performance implications.

**Pros and Cons of Each Approach**

1. **Direct Comparison (`<`)**
	* Pros: Simple and straightforward, easy to understand.
	* Cons: May result in floating-point arithmetic or integer overflows for very large values.
2. **Modulo Operation (`%` )**
	* Pros: Efficient for even/odd checks, reduces potential for overflows.
	* Cons: Requires modulo operation, which may be slower than direct comparison.
3. **Bitwise AND (`&`)**
	* Pros: Fast and efficient, minimizes the number of operations required to check if a value is odd.
	* Cons: May require additional instructions (e.g., bitwise shift) to convert to an even/odd flag.

**Library and Special JS Features**

There are no libraries or special JavaScript features used in this benchmark. The `getRandomUint32` function is a simple utility function that can be easily implemented by any JavaScript engine.

**Device and Browser Considerations**

The benchmark results show that Firefox 128 on Windows Desktop outperforms the other options. This may be due to optimizations or features specific to Firefox, such as Just-In-Time (JIT) compilation or hardware acceleration.

**Other Alternatives**

For generating boolean values from integers, you can also consider using:

* Bitwise shift operators (`>>` for right shift and `<<` for left shift) in combination with the least significant bit.
* Modular arithmetic operations other than `%`, such as using the exponentiation operator (`**`) or the modulo operator (`%`).
* Using a library like NumJS or Bigint.js to handle large integers.

Keep in mind that these alternatives may have different performance characteristics and trade-offs, depending on the specific use case and requirements.

Related benchmarks:

Bool generation from uint32 (version: 1)

Comparing performance of: Compare to half of max int vs Mod even/odd vs Bitwise even/odd

Created: one year ago by: Registered User

Jump to the latest result

Compare to half of max int

Mod even/odd

Bitwise even/odd

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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