Benchmark: Coordinate test 6

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 );
Other test 4
var xPos = Math.random() * width; var xQuad = ~~( xPos * invertedHalfWidth );
If test
var xPos = Math.random() * width; var xQuadLeft = 0; if( xPos >= halfWidth ) xQuadLeft = 1;
If test 2
var xPos = Math.random() * width; if( xPos < halfWidth ) var xQuadLeft = 0; else var xQuadLeft = 1;

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
Other test 4
If test
If test 2

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 benchmark and analyze what's being tested.

**Benchmark Overview**

The benchmark is designed to measure the performance of different JavaScript comparisons, specifically:

* Conditional comparison
* Bitwise comparison
* Other test 1: `xPos ^ halfWidth && (` (using logical AND)
* Other test 2: `xPos == width ? 1 : (` (using equality operator with integer context)
* Other test 3: `~~( xPos * invertedHalfWidth )` (using the bitwise NOT operator on an integer result)
* Other test 4: `~~( xPos * invertedHalfWidth )` (same as above, but without specifying a variable name)

**What's being tested**

Each test case is designed to measure the performance of a specific comparison operation. The tests are comparing different approaches to achieve the same result.

Here's a breakdown of each test case:

1. **Conditional comparison**: Tests the `xPos < halfWidth ? 0 : 1` syntax.
2. **Bitwise comparison**: Tests the `diff |= diff >> 1 | 0x80000000;` syntax, which performs a bitwise OR operation with a shifted value and a mask.
3. **Other test 1**: Tests the `xPos ^ halfWidth && (` syntax, which uses logical AND with an expression that returns either 0 or 1.
4. **Other test 2**: Tests the `xPos == width ? 1 : ( ... )` syntax, which uses equality operator with integer context.
5. **Other test 3**: Tests the `~~( xPos * invertedHalfWidth )` syntax, which performs a bitwise NOT operation on an integer result.
6. **Other test 4**: Same as above, but without specifying a variable name.

**Variables and constants**

* `xPos`: A variable representing a value to be compared.
* `halfWidth`: A constant representing half of the maximum possible value for `xPos`.
* `invertedHalfWidth`: The bitwise NOT of `halfWidth`.

**Performance implications**

The performance differences between these tests are likely due to:

* Branch prediction and misprediction penalties in the CPU.
* Cache misses and hits, as some operations may require access to different cache lines.
* Instruction-level parallelism (ILP) and pipelining effects.

**Interpretation of results**

The benchmark results show that the optimal approach depends on the specific test case. However, generally speaking:

* Conditional comparisons tend to be faster due to better branch prediction and fewer mispredictions.
* Bitwise comparisons can be faster if the CPU has a wide set of instructions for bitwise operations and can execute them in parallel.

**Conclusion**

This benchmark highlights the importance of considering different performance characteristics when choosing an approach to comparison operations. By understanding the nuances of each test case, developers can optimize their code for better performance and make informed decisions about the best way to compare values in their specific use cases.

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	3529160.0 Ops/sec
Bitwise comparison	2889343.2 Ops/sec
Other test	2480713.0 Ops/sec
Other test 2	2941605.2 Ops/sec
Other test 3	2926175.0 Ops/sec
Other test 4	3594254.8 Ops/sec
If test	3533187.2 Ops/sec
If test 2	3457704.8 Ops/sec

Related benchmarks:

Coordinate test 6 (version: 0)

Comparing performance of: Conditional comparison vs Bitwise comparison vs Other test vs Other test 2 vs Other test 3 vs Other test 4 vs If test vs If test 2

Created: 5 years ago by: Guest

Jump to the latest result

Conditional comparison

Bitwise comparison

Other test

Other test 2

Other test 3

Other test 4

If test

If test 2

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):