Re: [PATCH for-8.2 0/7] tcg/ppc: Support power10 prefixed instructions

[Richard Henderson]

On 8/6/23 04:55, Nicholas Piggin wrote:
> On Sat Aug 5, 2023 at 7:33 AM AEST, Richard Henderson wrote:
> > Emit one 64-bit instruction for large constants and pc-relatives.
> > With pc-relative addressing, we don't need REG_TB, which means we
> > can re-enable direct branching for goto_tb.
>
> Very cool. I tested this on a POWER10 and it has been stable so
> far. Using mttcg with SMP 8 machine, with this patch, a parallel
> gcc compile job in a Linux distro is 11.5% faster. Is such a big
> improvment expected?

Possibly, given that we had to disable direct branch patching for USE_REG_TB.


r~