This is the mail archive of the
gcc-bugs@gcc.gnu.org
mailing list for the GCC project.
[Bug tree-optimization/18595] [4.0 Regression] IV-OPTS is O(N^3)
- From: "dberlin at dberlin dot org" <gcc-bugzilla at gcc dot gnu dot org>
- To: gcc-bugs at gcc dot gnu dot org
- Date: 24 Jan 2005 22:25:05 -0000
- Subject: [Bug tree-optimization/18595] [4.0 Regression] IV-OPTS is O(N^3)
- References: <20041121145949.18595.pinskia@gcc.gnu.org>
- Reply-to: gcc-bugzilla at gcc dot gnu dot org
------- Additional Comments From dberlin at gcc dot gnu dot org 2005-01-24 22:25 -------
Subject: Re: [4.0 Regression] IV-OPTS is O(N^3)
>
> Other part is that scev tries to be too clever. Without need to
> represent nonaffine induction variables (that we do not use anywhere)
> we could use more memory efficient representation of ivs.
> Without need to handle symbolic references (that we also do not use
> anywhere, we could store evolutions in a fully instantiated form, and
> we would not need instantiate_parameters/resolve_mixers functions atall.
Uh, symbolic references are or will be used to do data dependence when
MEM_REF and ARRAY_REF couldn't be generated from the pointers.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18595