Hi, > On 7 Nov 2014, at 07:52, Anand Avati <avati@xxxxxxxxxxx> wrote: > On Thu, Nov 6, 2014 at 8:22 PM, Anton Altaparmakov <aia21@xxxxxxxxx> wrote: > > On 7 Nov 2014, at 01:46, Jeff Moyer <jmoyer@xxxxxxxxxx> wrote: > > Minor nit, but I'd rather read something that looks like this: > > > > if (type == READ && (flags & RWF_NONBLOCK)) > > return -EAGAIN; > > else if (type == WRITE && (flags & RWF_DSYNC)) > > return -EINVAL; > > But your version is less logically efficient for the case where "type == READ" is true and "flags & RWF_NONBLOCK" is false because your version then has to do the "if (type == WRITE" check before discovering it does not need to take that branch either, whilst the original version does not have to do such a test at all. > > Seriously? Of course seriously. > Just focus on the code readability/maintainability which makes the code most easily understood/obvious to a new pair of eyes, and leave such micro-optimizations to the compiler.. The original version is more readable (IMO) and this is not a micro-optimization. It is people like you who are responsible for the fact that we need faster and faster computers to cope with the inefficient/poor code being written more and more... And I really wouldn't hedge my bets on gcc optimizing something like that. The amount of crap assembly produced from gcc that I have seen over the years suggests that it is quite likely it will make a hash of it instead... Best regards, Anton > Thanks -- Anton Altaparmakov <aia21 at cam.ac.uk> (replace at with @) University of Cambridge Information Services, Roger Needham Building 7 JJ Thomson Avenue, Cambridge, CB3 0RB, UK -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
