This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: fix opt/2960
- From: David Edelsohn <dje at watson dot ibm dot com>
- To: "Ulrich Weigand" <Ulrich dot Weigand at de dot ibm dot com>, Richard Henderson <rth at redhat dot com>
- Cc: gcc-patches at gcc dot gnu dot org
- Date: Tue, 08 Oct 2002 16:13:16 -0400
- Subject: Re: fix opt/2960
Before the "don't copy loop headers" change, doloop worked.
Richard's recent comment suggests that the change does not necessarily
promote better, smaller code, which I agree. Richard tried to fix doloop
by removing the "execute half of the loop one more time" trick, which
seems to be causing more breakage.
May I suggest that we simply revert the loop headers change, which
Richard wants to do in any case, and add a comment about the fragile
doloop code without trying to fix anything? Nothing was broken before we
started changing things. Let's not try to fix something which isn't
broken and leave that effort to masochists.
Hopefully 3.4 will have a cfg-based loop optimizer and we can toss
all of this code instead of pulling on this string when there are more
important things to be working on.
Thanks, David