Benchmark: Math.floor vs |0 vs (int)

Tests:

Math.floor
var a = Math.floor(2+5.5);
|0
var a = (2+5.5)|0;

Rendered benchmark preparation results:

Suite status: <idle, ready to run>

Previous results

Test case name	Result
Math.floor
\|0

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:137.0) Gecko/20100101 Firefox/137.0

Browser/OS: Firefox 137 on Windows

View result in a separate tab

Test name	Executions per second
Math.floor	932726272.0 Ops/sec
\|0	904844224.0 Ops/sec

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

LLMs can make mistakes. Check important info.

I'd be happy to explain the benchmark and its options.

**What is being tested?**

The benchmark measures the performance of two different ways to round down a decimal number: using the `Math.floor()` function, using the bitwise OR operator (`|`) with 0, and casting to an integer (`(int)`).

**Options compared**

There are three options being compared:

1. **`Math.floor()`**: This is a built-in JavaScript function that returns the largest integer less than or equal to the given number.
2. **`|0`**: This is a bitwise OR operator with 0, which performs a binary operation and then casts the result to an integer. In this case, it effectively rounds down the decimal number to the nearest integer.
3. ** `(int)`**: This is not a standard JavaScript syntax for casting to an integer. It's unclear what language or context this might be intended for, but in standard JavaScript, you would use `Math.floor()` or `|0` instead.

**Pros and Cons**

1. **`Math.floor()`**:
	* Pros: Well-known function, widely supported, easy to read and understand.
	* Cons: May incur a small overhead due to the function call.
2. **`|0`**:
	* Pros: Fast and lightweight, doesn't incur the overhead of a function call.
	* Cons: Less readable than `Math.floor()`, may not be immediately clear what it does without context.
3. ** `(int)`**:
	* Pros: None ( unclear syntax).
	* Cons: Not standard JavaScript, likely to cause confusion and errors.

**Library and syntax**

There is no library involved in this benchmark.

**Special JS feature or syntax**

There is a special syntax used in the `|0` option, which is the bitwise OR operator (`|`). While this is a valid operator in JavaScript, it's not commonly used for rounding down decimal numbers. The `(int)` syntax is also non-standard and likely intended to simulate integer casting.

**Other alternatives**

If you wanted to round down a decimal number in JavaScript, other alternatives could include:

* Using the `Math.round()` function with the `-1` option (e.g., `Math.round(x) - 0.5`)
* Using the ternary operator (`x | 0`)
* Implementing your own rounding algorithm using bitwise operations.

Keep in mind that these alternatives may have different performance characteristics and readability compared to the options being benchmarked here.

Related benchmarks:

Math.floor vs |0 vs (int) (version: 0)

Comparing performance of: Math.floor vs |0

Created: 8 years ago by: Guest

Jump to the latest result

Math.floor

|0

Suite status: <idle, ready to run>

Fastest: N/A

Slowest: N/A

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