This is the mail archive of the
gcc@gcc.gnu.org
mailing list for the GCC project.
Re: Loop unroll fixes
- To: Zoltan Hidvegi <hzoli at hzoli dot 2y dot net>
- Subject: Re: Loop unroll fixes
- From: Franz Sirl <Franz dot Sirl-kernel at lauterbach dot com>
- Date: Thu, 04 Oct 2001 15:39:47 +0200
- Cc: gcc at gcc dot gnu dot org,Mark Mitchell <mark at codesourcery dot com>,Bernd Schmidt <bernds at redhat dot com>
At 01:35 14.09.2001, Zoltan Hidvegi wrote:
>Sorry to bug you all with that again, but I wonder if the fix for PR
>3384 could be applied to the 3.0 branch and the mainline (on the
>mainline the doloop.c patch conflicts with Bernd Smith's change to fix
>a subset of the bugs fixed by my patches that also generates a slighly
>less efficient code). See PR 3384, and threads
>http://gcc.gnu.org/ml/gcc-patches/2001-07/msg01080.html
>http://gcc.gnu.org/ml/gcc-bugs/2001-07/msg00750.html
>
>I think this is a bad regression from 2.95.2. -funroll-loops is a
>powerful and widely used optimization. GNATS already have a high
>priority assigned to this bug, please, someone look at it and either
>check it in or do some alrernative fix. Bootstrapped and passed the
>regressions on powerpc-ibm-aix4.3.3 and on i686-pc-linux-gnu, at least
>it did some time back just before 3.0.1 was released, but there has
>been no change in the files involved since than.
Mark, Bernd, what about this for mainline and 3.0.2? Somehow the patch
never made it past an half-approved state. I stumbled over this while
tracking another (unfortunately unrelated, more info later today) loop bug.
OK to commit Zoltans patch to mainline (after he sends me an updated
mainline version) and branch after bootstrap/regtest on x86/ppc?
Franz.