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Comment by monkeyelite

3 days ago

> Your understanding of how bounds checking works in modern languages and compilers is not up to date.

One I am familiar with is Swift - which does exactly this because it’s a library feature of Array.

Which languages will always be able to determine through function calls, indirect addressing, etc whether it needs to bounds check or not?

And how will I know if it succeeded or whether something silently failed?

> if you have an image processing algorithm that is literally reading every single pixel one-by-one to perform a 2-instruction operation and calculating bounds check on every access in the year 2025, you're doing a lot of things very wrong

I agree. And note this is an example of a scenario you can encounter in other forms.

> Do you have any examples at all? Or is this just speculation?

Yes. Java and python are not competitive for graphics and audio processing.

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monkeyelite

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Aurornis  2 days ago

> Yes. Java and python are not competitive for graphics and audio processing.

Because Python is an interpreted language and Java has garbage collection, not because they have bounds checking.

Using a language like Rust the bounds checking overhead compared to C code is usually minimal, like 0-5%. The compiler can even optimize away many bounds checks (safely) if you structure your code properly, such as with iterators.

Here's an example article : https://shnatsel.medium.com/how-to-avoid-bounds-checks-in-ru...

Make sure you read the note about how the author was mistaken about the 15% speedup from bounds checking. The actual bounds check change was much less, like a couple percent. You can even structure your code so that the bounds check disappears altogether when the compiler can confirm safety at compile time.