Re: [OpenBIOS] [PATCH] Add tbu@ and tbl@ words

[Segher Boessenkool]

On Sat, Dec 30, 2017 at 02:01:41AM +0100, BALATON Zoltan wrote:
> I've tried to implement it the way I've suggested and came up with the 
> patch below, but it does not seem to work. I think this is because the 
> arithmetic in get-msec overflows and does not get the right values. Could 
> it be it works in SLOF because that runs on 64bit? Or is something needed 
> to tell Forth to use 64bit values on PPC32? Any ideas?
> +static void tb_fetch(void)
> +{
> unsigned long tbl, tbu;
> do {
>  tbu = mftbu();
>  tbl = mftb();
> } while (tbu != mftbu());
> DPUSH(((uint64_t)tbu << 32) | tbl);
>
> +}

Whether the code here is correct or not, it is simpler to just write it as

PUSH(tbl);
    PUSH(tbu);

Segher