Since afterstart = 0, there should be no loop to optimize out except ONE value test
One hundred cycles for that would seem excessive for me TWENTY THOUSAND CYCLES for a _zero_ loop?!? Maybe in Java El mié, 24 mar 2021 a las 14:30, Gregory Nutt (<spudan...@gmail.com>) escribió: > > > Weird behavior: > > > > Simply changing loop counter variable from uint16_t to volatile uint16_t > > causes initial delay (with variable delay = 0) going from ~500 ns to > ~120 us > > > > The code is > > > > uint16_t delay; > > > > select_function(); > > for(delay = 0; delay < transfer->dev->afterstart; delay++); > > > > Any ideas? > > > I imagine that the delay loop is no longer being optimized out. That is > what volatile is supposed to do (people often don't understand that, it > is a great interview question). >
