Skip site navigation (1)Skip section navigation (2)
Date:      Fri, 4 Jan 2019 11:02:18 +0000
From:      Alejandro Martinez <unledev@gmail.com>
To:        Brian Neal <brian@aceshardware.com>
Cc:        Garance A Drosehn <drosih@rpi.edu>, freebsd-hackers@freebsd.org
Subject:   Re: Speculative: Rust for base system components
Message-ID:  <CAFwFPkziF%2BEvZ2fEv1fErfmDujPm9UhxvoYUBoCo-%2BtjXtBWmw@mail.gmail.com>
In-Reply-To: <92bd5362-d898-aa12-8f3d-9fbe23f38e0c@aceshardware.com>
References:  <ca76e5f7-6e59-bd67-144a-90ad66f0252e@metricspace.net> <7d7bc47d-04cf-2f9b-00a3-e3d9d92b3623@aceshardware.com> <72922F2C-9D27-47AA-BB1C-2DA8589CF008@rpi.edu> <92bd5362-d898-aa12-8f3d-9fbe23f38e0c@aceshardware.com>

next in thread | previous in thread | raw e-mail | index | archive | help
Hi Brian,

On Tue, Jan 1, 2019 at 7:02 AM Brian Neal <brian@aceshardware.com> wrote:
>
> It was a debug build with no optimization for either compiler. But we
> can easily run a variety of settings for comparison:
>
> Compiler              Flags                 Inst. Count Build Time
> ======================================================================
> clang 7.0.0           none                           33 296ms
>                        -O3                            23 341ms
> rustc 1.31.0          none                          110 606ms
>                        -C opt-level=3                 67 643ms
> gcc 8.2               none                           37 211ms
>                        -O2                            24 249ms
>                        -O3                          119* 206ms
>
> * With -O3, gcc unrolled and vectorized the loop. The other compilers
> did not emit vectorized code at any of the standard optimization levels.
>
> So, essentially, double the build time and ~3 times the code for the
> same logic.

Can you share your exact tests so others can replicate?

Thanks,
  Alex



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CAFwFPkziF%2BEvZ2fEv1fErfmDujPm9UhxvoYUBoCo-%2BtjXtBWmw>