This is the mail archive of the
gcc-bugs@gcc.gnu.org
mailing list for the GCC project.
[Bug optimization/11710] loop optimizer cannot figure out # iterations for shift and / * "increments"
- From: "rakdver at atrey dot karlin dot mff dot cuni dot cz" <gcc-bugzilla at gcc dot gnu dot org>
- To: gcc-bugs at gcc dot gnu dot org
- Date: 29 Jul 2003 19:27:35 -0000
- Subject: [Bug optimization/11710] loop optimizer cannot figure out # iterations for shift and / * "increments"
- References: <20030729181502.11710.rguenth@tat.physik.uni-tuebingen.de>
- Reply-to: gcc-bugzilla at gcc dot gnu dot org
PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=11710
------- Additional Comments From rakdver at atrey dot karlin dot mff dot cuni dot cz 2003-07-29 19:27 -------
Subject: Re: loop optimizer cannot figure out # iterations for shift and / * "increments"
Hello,
> I can confirm this on the mainline (20030729) on powerpc-apple-darwin6.6 but it is not fixed on
> the rtlopt branch sorry.
yes, this feature is not supported neither by old nor by new loop
optimizer just now. It might be with the new iv analysis that is being
written for tree-ssa (although this is only my guess). Handling
non-linear induction variables brings very little gain in practice,
as they are rare, and it has very small priority for me now.
Zdenek