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   pinskia (pinskia@hachyderm.io)'s status on Tuesday, 17-Dec-2024 07:09:47 JST pinskia

   in reply to

   • Paul Khuong

   @pkhuong GCC even has an IR for this specific thing, called exact divide. It is used for pointer subtraction.

   • Embed this notice
     Paul Khuong (pkhuong@discuss.systems)'s status on Tuesday, 17-Dec-2024 07:09:50 JST Paul Khuong

     Let's say you know the input is an exact multiple of your integer divisor. Does that let you come up with a smaller div-by-mul constant?

     EDIT: I don't mean a reciprocal inverse mod 2^w, but literally a fixed point div by mul (which also avoids the need to ensure the divisor is odd).

     https://discuss.systems/@pkhuong/113663255154088174