From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Tim Prince" <tprince@computer.org>
To: "Matthias Kurz" <mk@baerlap.north.de>, <gcc@gcc.gnu.org>
Subject: Re: best optimization under IRIX ?
Date: Tue, 05 Sep 2000 23:36:00 -0000
Message-id: <002c01c017cd$1cce71c0$8f6a8ad1@timayum4srqln4>
References: <20000906052036.A23559@baerlap.north.de>
X-SW-Source: 2000-09/msg00081.html

You must add -funroll-loops or -funroll-all-loops; I usually got about 70%
of MipsPro 7.3 Fortran speed from g77, and gcc should be closer than that to
the speed of MipsPro C.  -O3 does interprocedural analysis only in a forward
direction within one file, while -Ofast does it it link time.  Also, you
must perform many of the usual optimizations in source code as gcc is much
more faithful to your code.

----- Original Message -----
From: "Matthias Kurz" <mk@baerlap.north.de>
To: <gcc@gcc.gnu.org>
Sent: Tuesday, September 05, 2000 8:20 PM
Subject: best optimization under IRIX ?


>
> Hi.
>
> What are the optimization options that give the maximum speed on
> a O2000/R10000 ?
> Currently the native "cc" with "-32 -Ofast=IP27" generates code that runs
> twice as fast as "gcc -mabi=n32 -O3 -mips3 -r4000". I see neither -mips4
> nor -r10000 in the man page.
>
>
>    (mk)
>
> --
> Matthias Kurz; Fuldastr. 3; D-28199 Bremen; VOICE +49 421 53 600 47