Benchmark: Coordinate test 4

Script Preparation code:

var width = 480;
var halfWidth = width >> 1;
var invertedHalfWidth = 1 / halfWidth;

Tests:

Conditional comparison
var xPos = Math.random() * width; var xQuadLeft = xPos < halfWidth ? 0 : 1;
Bitwise comparison
var xPos = Math.random() * width; var diff = xPos ^ halfWidth; diff |= diff >> 1; diff |= diff >> 2; diff |= diff >> 4; diff |= diff >> 8; diff |= diff >> 16; diff &= ~(diff >> 1) | 0x80000000; diff &= (xPos ^ 0x80000000) & (halfWidth ^ 0x7fffffff); var xQuad = !!diff;
Other test
var xPos = Math.random() * width; var xQuad = xPos ^ halfWidth && ( !(halfWidth ^ 0) || ( (xPos / halfWidth) | 0 ) );
Other test 2
var xPos = Math.random() * width; var xQuad = xPos == width ? 1 : ( ( xPos * invertedHalfWidth ) | 0 );
Other test 3
var xPos = Math.random() * width; var xQuad = xPos == width ? 1 : ~~( xPos * invertedHalfWidth );

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Conditional comparison
Bitwise comparison
Other test
Other test 2
Other test 3

Fastest: N/A

Slowest: N/A

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

LLMs can make mistakes. Check important info.

Let's dive into the world of JavaScript microbenchmarks.

**What is tested?**

The provided JSON represents a set of benchmark tests for a specific piece of code that calculates a "coordinate" based on the `width` variable. The tests vary in how they compare this calculated value with the `halfWidth` and/or `invertedHalfWidth`.

**Options compared:**

1. **Conditional comparison**: This option uses a simple if-else statement to determine whether the calculated coordinate is less than or greater than the `halfWidth`. The pros of this approach are simplicity and ease of understanding. However, it may be slower due to the branching.
2. **Bitwise comparison**: This option uses bitwise operators (`^`, `&`, `|`) to compare the calculated coordinate with `halfWidth` and/or `invertedHalfWidth`. The pros of this approach are potentially faster execution speeds, as bitwise operations can be more efficient than arithmetic operations. However, the code may be less readable due to the use of bitwise operators.
3. **Other test 1**: This option uses a ternary operator to compare the calculated coordinate with `width`. The pros of this approach are concise and easy to read. However, it may be slower due to the unnecessary arithmetic operations.
4. **Other test 2**: Similar to Other test 1, but uses the bitwise OR operator (`|`) to combine two comparisons. This approach is likely faster than the previous one but might not be as readable.
5. **Other test 3**: Similar to Other test 2, but uses a cast operator (`~~`) to perform a bitwise operation. The pros of this approach are potentially faster execution speeds and concise code.

**Library used:**

None mentioned in the provided JSON.

**Special JS features or syntax:**

There is no explicit mention of special JavaScript features or syntax being used beyond standard arithmetic operations.

**Considerations:**

When writing benchmarks, it's essential to consider factors like:

* **Branch prediction**: The CPU can predict which branch (if-else statement) will be taken more often. In this case, the Conditional comparison might benefit from branch prediction.
* **Cache locality**: Accessing adjacent variables in memory can improve cache performance.
* **Code readability**: While benchmarks aim for speed, code readability is still essential for maintainability and understanding.

**Alternatives:**

If you wanted to write similar benchmarks using different approaches or languages, some alternatives could be:

* **Language-specific benchmarks:** Consider writing benchmarks in a language like C++ or Rust, which can offer more direct access to hardware performance characteristics.
* **Hardware-centric benchmarks:** Measure the performance of specific hardware components, such as GPU or CPU instructions, to compare their efficiency.
* **Higher-level abstractions:** Use frameworks or libraries that provide higher-level abstractions for performance benchmarking, like Google's Benchmark library.

Keep in mind that each approach has its strengths and weaknesses, and choosing the right one depends on your specific goals, resources, and expertise.

Latest run results:

Run details: (Test run date: 5 years ago)

User agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/75.0.3770.100 Safari/537.36

Browser/OS: Chrome 75 on Mac OS X 10.14.5

View result in a separate tab

Test name	Executions per second
Conditional comparison	3384954.8 Ops/sec
Bitwise comparison	2342102.8 Ops/sec
Other test	2052380.4 Ops/sec
Other test 2	2482553.0 Ops/sec
Other test 3	2414226.5 Ops/sec

Related benchmarks:

Coordinate test 4 (version: 0)

Comparing performance of: Conditional comparison vs Bitwise comparison vs Other test vs Other test 2 vs Other test 3

Created: 5 years ago by: Guest

Jump to the latest result

Conditional comparison

Bitwise comparison

Other test

Other test 2

Other test 3

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):