3 points
Godbolt to the rescue! So gcc 13.2 certainly does produce the same code, though a lot of other versions and compilers do it slightly differently. Surprisingly, clang doesn’t optimise this and uses idiv for the modulo version.
1 point
Awesome, thank you for that link. I should have guessed this was a thing but it hadn’t even occurred to me.
And yeah, it is surprising that clang doesn’t treat mod power of 2 as a special case. It looks like I can’t type in code on mobile, does clang handle divide by power of 2 as a idiv or shift?
