[Blackthorn]

We find constexpr (and associated templates) essential for when we need to avoid branch penalties. It makes the code so much simpler and cleaner than the alternative. I'm glad the language caters to the needs of everyone, even if any individual person (self included) only uses a little bit of it.

[PaulDavisThe1st]

Yeah, I had an opportunity to use it for more or less precisely this case (avoiding a branch) a couple of years ago, and it was a delight to find.

  template<bool condition>
  void method () { .... if (condition) /* constexpr */ { extra_code; } .... }

Which then allows method<true> and method<false> without a runtime branch.

[anematode]

The cardinal question: is the benefit of removing that branch worth the increase in i-cache footprint? I think it depends quite a bit... but also, the speed increases IME from doing this kind of thing can result not merely from the branch removal, but from the code duplication itself. Even if the contents of the branch doesn't directly mention the condition, duplication allows the surrounding code to be separated in the branch predictor, and it's quite common that these conditions will correlate with different branch frequencies in the surrounding. code.