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Re: [PR91598] Improve autoprefetcher heuristic in haifa-sched.c
- From: Wilco Dijkstra <Wilco dot Dijkstra at arm dot com>
- To: Maxim Kuvyrkov <maxim dot kuvyrkov at linaro dot org>, Richard Guenther <richard dot guenther at gmail dot com>
- Cc: "gcc-patches at gcc dot gnu dot org" <gcc-patches at gcc dot gnu dot org>, Alexander Monakov <amonakov at ispras dot ru>, nd <nd at arm dot com>
- Date: Tue, 3 Sep 2019 16:55:10 +0000
- Subject: Re: [PR91598] Improve autoprefetcher heuristic in haifa-sched.c
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Hi Maxim,
> > Autoprefetching heuristic is enabled only for cores that support it, and isn't active for by default.
>
> It's enabled on most cores, including the default (generic). So we do have to be
> careful that this doesn't regress any other benchmarks or do worse on modern
> cores.
I benchmarked your scheduler change on a few AArch64 machines, and it either has
no effect or a positive effect on SPECFP with no major outliers (and only minor
codesize differences). So I think your proposed patch is OK as is.
Cheers,
Wilco