Benchmark: Increment/decrement operator in condition vs. code block of while loop

Tests:

increment operator in code block
var i, n; i = 0; n = 0; while (i < 1000) { n++; // let the loop do something i++; }
increment operator in condition
var i, n; i = 0; n = 0; while (i++ < 1000){ n++; // let the loop do something }
decrement operator in code block
var i, n; i = 1000; n = 0; while (i > 0) { n++; // let the loop do something i--; }
decrement operator in condition
var i, n; i = 1000; n = 0; while (i-- > 0) { n++; // let the loop do something }

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
increment operator in code block
increment operator in condition
decrement operator in code block
decrement operator in condition

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 break down the benchmark and explain what's being tested.

**Benchmark Overview**

The benchmark tests the performance of JavaScript engines on four different scenarios:

1. Increment operator in code block
2. Increment operator in condition (while loop)
3. Decrement operator in code block
4. Decrement operator in condition (while loop)

These scenarios involve using increment (`i++`) and decrement (`i--`) operators within a `while` loop, which is a fundamental construct in JavaScript.

**Options Being Compared**

There are two main options being compared:

1. **Increment operator in code block**: The increment operator is applied to the variable `i` inside the `while` loop.
2. **Increment operator in condition**: The increment operator is used as part of the condition in the `while` loop, rather than applying it within the loop body.

**Pros and Cons**

Using an increment operator in code block (Option 1) can lead to:

* Faster execution: Since the increment operator is not applied after the loop iteration, it's less expensive from a performance perspective.
* Better cache locality: The incremented value of `i` is more likely to be stored in the cache, reducing memory access times.

However, this approach might also lead to:

* Potential issues with loop control: If the increment operator is used carefully, it can help improve loop control and reduce unnecessary iterations.

On the other hand, using an increment operator in condition (Option 2) can result in:

* Slower execution: The increment operator needs to be evaluated after each iteration, which might lead to additional overhead.
* Reduced cache locality: The incremented value of `i` is less likely to be stored in the cache, increasing memory access times.

However, this approach can also help with loop control and reduce unnecessary iterations if implemented correctly.

**Library Usage**

None of the benchmark test cases use any external libraries or frameworks. The JavaScript code provided only relies on built-in JavaScript features.

**Special JS Features/Syntax**

There are no special JS features or syntax used in these benchmarks, such as async/await, Promises, or generators. However, it's worth noting that some modern JavaScript engines might optimize certain loop constructs using advanced techniques like loop unrolling or cache-aware optimization.

**Other Alternatives**

Some alternative approaches to benchmarking JavaScript performance include:

1. **WebAssembly**: Benchmarking JavaScript engines on WebAssembly-based code can provide more accurate results, as WebAssembly is a low-level, assembly-like language that's closer to the machine.
2. **Native Code**: Compiling JavaScript code to native machine code using tools like V8 or SpiderMonkey can also provide performance insights.
3. **Loop Unrolling**: Some benchmarking frameworks use loop unrolling techniques to reduce the number of iterations and improve performance measurements.

Keep in mind that each approach has its own strengths and limitations, and the choice of benchmarking method depends on the specific use case and requirements.

Latest run results:

Run details: (Test run date: 4 years ago)

User agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/79.0.3945.130 Safari/537.36

Browser/OS: Chrome 79 on Windows

View result in a separate tab

Test name	Executions per second
increment operator in code block	1673636.1 Ops/sec
increment operator in condition	1114508.9 Ops/sec
decrement operator in code block	1696487.2 Ops/sec
decrement operator in condition	1130421.2 Ops/sec

Related benchmarks:

Increment/decrement operator in condition vs. code block of while loop (version: 0)

Comparing performance of: increment operator in code block vs increment operator in condition vs decrement operator in code block vs decrement operator in condition

Created: 4 years ago by: Registered User

Jump to the latest result

increment operator in code block

increment operator in condition

decrement operator in code block

decrement operator in condition

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):