Have you ever encountered code that behaves in a counterintuitive way?

General
1

I ran into a case where adding an extra line of code to a loop caused the performance to improve despite the fact that it was now having to do more work through each iteration than before. I just wrote a blog post about it.

Have you ever encountered counterintuitive behavior in your code?

1 Like
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Not in my code but almost everywhere in Windows and Microsoft apps :nauseated_face: .

4

@Geoff_Perlman - if you haven’t seen it, you might enjoy this short YouTube series:

It’s a really interesting and informative series, showing how different compilers (GCC and Clang) and different targets (x86, ARM) can end up creating significantly different sets of instructions based on:

  • Optimization level
  • Targeted CPU’s “generation”
  • How the actual code is structured

I really enjoyed the whole series. It’s fascinating to see how clever (and occasionally not so clever) compilers can be in trying to optimize code.

Anthony

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Maybe not encountered, but I sure have created a lot.

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Your blog suggested that the ARM was involved but wondering if it’s a compiler artifact? Going to check some of my encryption methods and see if variations make a difference.