Benchmark: switch vs if (3)

HTML Preparation code:

<script>
    var arr = [];
    var res = [0, 0];
    var generateRandomInteger = function(min, max) {
        return Math.floor(min + Math.random() * (max - min + 1))
    }
    var test01 = function() {
        let k = 0;
        for (const v of arr) {
            switch (v) {
                case 1:
                    k += 1;
                    break;
                case 2:
                    k += 2;
                    break;
                case 3:
                    k += 3;
                    break;
                case 4:
                    k += 5;
                    break;
                case 5:

                    k += 7;
                    break;
                case 6:
                    k += 11;
                    break;
                case 7:

                    k += 13;
                    break;
                case 8:

                    k += 17;
                    break;
                default:
                    k += 19;;
            }
        }
        res[0] = k;
    }
    var test02 = function() {

        let k = 0;
        for (const v of arr) {
            if (v === 1) {

                k += 1;
            } else if (v === 2) {

                k += 2;
            } else if (v === 3) {

                k += 3;
            } else if (v === 4) {

                k += 5;
            } else if (v === 5) {

                k += 7;
            } else if (v === 6) {

                k += 11;
            } else if (v === 7) {

                k += 13;
            } else if (v === 8) {

                k += 17;
            } else {

                k += 19;
            }
        }
        res[1] = k;

    }
</script>

Script Preparation code:

Benchmark.prototype.setup = function() {
    arr = new Array(256).fill(0).map(e => generateRandomInteger(1, 16));
    if (test01() !== test02()) throw new Error('test error');
};
Benchmark.prototype.teardown = function() {
    arr.length = 0;
    res = [0, 0];
}

Tests:

switch
test01();
if
test02();

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
switch
if

Fastest: N/A

Slowest: N/A

Latest run results:

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

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/123.0.0.0 Safari/537.36 Zaap3.6.8

Browser/OS: Chrome 123 on Windows

View result in a separate tab

Test name	Executions per second
switch	1248273.2 Ops/sec
if	2987279.5 Ops/sec

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

LLMs can make mistakes. Check important info.

Let's dive into the provided benchmark definition and explore what's being tested.

**Benchmark Definition**

The benchmark is designed to compare the performance of two approaches: using a `switch` statement versus an `if-else` chain. The test data is generated by creating an array of 256 random integers between 1 and 16, which are then used as input values for both tests.

**Script Preparation Code**

The script preparation code sets up the benchmark environment. It defines two functions, `test01()` and `test02()`, which will be executed in the benchmark. These functions are responsible for calculating a value `k` based on the input array `arr`. The difference between these functions is that `test01()` uses a `switch` statement, while `test02()` uses an `if-else` chain.

**Html Preparation Code**

The HTML preparation code defines a script that generates a random integer function `generateRandomInteger()`, which will be used to populate the input array `arr`. It also initializes variables `arr`, `res`, and defines the two test functions `test01()` and `test02()`.

**Individual Test Cases**

There are two individual test cases:

1. `switch`: This test case executes the `test01()` function, which uses a `switch` statement to calculate the value `k`.
2. `if`: This test case executes the `test02()` function, which uses an `if-else` chain to calculate the value `k`.

**Library and Purpose**

There is no explicit library mentioned in the benchmark definition. However, it's possible that some internal libraries or frameworks are being used under the hood.

**Special JS Feature/Syntax**

The benchmark does not explicitly use any special JavaScript features or syntax. However, it does rely on ES6+ features like `const`, `let`, and template literals.

**Performance Comparison**

The benchmark is designed to compare the performance of two approaches:

1. **Switch Statement**: The `switch` statement is a built-in control structure in JavaScript that allows for efficient comparison and branch execution.
2. **If-Else Chain**: An `if-else` chain is a more general-purpose control structure that can be used for conditional execution, but may incur additional overhead due to repeated comparisons.

**Pros and Cons**

Here are some pros and cons of each approach:

* **Switch Statement**:
	+ Pros:
		- Fast branch prediction
		- Low overhead for comparison operations
	+ Cons:
		- Limited flexibility in handling unknown cases
		- May require more code to handle multiple branches
* **If-Else Chain**:
	+ Pros:
		- Highly flexible and adaptable to new cases
		- Can be used for non-boolean comparisons (e.g., string matching)
	+ Cons:
		- Higher overhead due to repeated comparison operations
		- May have slower branch prediction

**Other Alternatives**

Some other alternatives that could be considered for this benchmark include:

1. **Object-based approach**: Instead of using a `switch` statement or an `if-else` chain, the code could use object-based methods (e.g., `switch` on an object property) to compare values.
2. **Regex-based approach**: The code could use regular expressions (regex) to match and compare values.
3. **Native array method**: JavaScript arrays have native methods like `indexOf()` or `findIndex()` that can be used for searching and comparison.

These alternatives may offer different performance characteristics, trade-offs in flexibility and readability, and require different optimizations or considerations.

Related benchmarks:

switch vs if (3) (version: 1)

Comparing performance of: switch vs if

Created: 2 years ago by: Registered User

Jump to the latest result

switch

if

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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