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kotlinlang

Hello, I have a math equation `val result = value * 100.0 / 255 `   Given that 100.0/255=0.392, is `val result = value * 0.392` better than the equation one in the performance of view.

I like the equation one because it keeps our math equation and is easier to read and understand. But still want to know whether these two have any performance different

I'm always hoping the compiler optimizes that for me but I never really confirmed

CLang O3 doesn't optimize it, so it's probably not allowed.

Specifically for floating point you can't really do a lot of optimizations while _exactly_ following IEEE floating point rules.

Turns out if you put parentheses, the generated bytecode shows the compiler precomputes (100.0/255) and uses 0.39215686274509803 instead

So the multiplication takes precedence over the division up there ?

Not real precedence, they just work left to right. But basically yes, it's equivalent to `(value * 100.0) / 255`

Ah, thanks, I always wondered how this works