On Fri. 15 janv. 2021 at 22:51, Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx> wrote:
> On 1/15/21 2:20 PM, Vincent MAILHOL wrote:
> > /* map the data length to an appropriate data length code */
> > u8 can_fd_len2dlc(u8 len)
> > {
> > switch(len) {
> > case 0 ... 8:
> > return len;
> > case 9 ... 12:
> > return 9;
> > case 13 ... 16:
> > return 10;
> > case 17 ... 20:
> > return 11;
> > case 21 ... 24:
> > return 12;
> > case 25 ... 32:
> > return 13;
> > case 33 ... 48:
> > return 14;
> > case 49 ... 64:
> > default:
> > return CANFD_MAX_DLC;
> > }
> > }
> >
> > And we will just leave the optimizations in the hand of the compiler.
>
> I've already tried this. It results in a longer object file on ARM, even if you
> remove the array....
You are right. I just checked the assembly code: it does a
dichotomy which means that in addition to being bigger, it is
also slower.
Please forget my previous message, it wasn't really smart.
Yours sincerely,
Vincent
> Marc
>
> --
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