Hi Michael, On Fri, 20 Jan 2023 16:40:10 +0100 Michael Grunditz <[email protected]> wrote:
> Hello, > > Is there any particular reason why it is empty? > My rect copy to fb in riscos uses neon. It is > a speed gain of about 40% compared to word/long word > copy from c. But I don't know how much it affects Genode. > > It seems like it ends up in /* eight bytes chunks */ but isn't that a > byte copy? > There is no particular reason why the implementation is (i.e. "was") empty. You can find a recent commit on the staging branch that applies a few obvious optimisations to all architectures, though: https://github.com/genodelabs/genode/commit/4d06661d7c3f7b798ec8228f04983bd4ae7cddcf For 32bit arm, I optimised the memcpy_cpu implementation a while ago (see Issue #4456). Interestingly, I could not see any improvements when using neon, at least on arm v7. I got the impression that the instruction density is not an issue when using the multi-word load/store (ldm/stm). Johannes _______________________________________________ Genode users mailing list [email protected] https://lists.genode.org/listinfo/users
