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[Bug tree-optimization/32921] [4.3/4.4 Regression] Revision 126326 causes 12% slowdown
- From: "mmitchel at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>
- To: gcc-bugs at gcc dot gnu dot org
- Date: 2 May 2008 14:16:03 -0000
- Subject: [Bug tree-optimization/32921] [4.3/4.4 Regression] Revision 126326 causes 12% slowdown
- References: <bug-32921-682@http.gcc.gnu.org/bugzilla/>
- Reply-to: gcc-bugzilla at gcc dot gnu dot org
------- Comment #52 from mmitchel at gcc dot gnu dot org 2008-05-02 14:16 -------
Yes, the "perfect pass" problem is what concerns me too. For example, if we
try to do dynamic reordering of passes, or allow users to specify that, we have
to worry that, in practice, the compiler will crash or generate wrong code.
We'll have no good way of ever validating even a small set of the possible
combinations.
Perhaps we need to make the passes fast, so we can run them more often? Or
weave some of them together, even though of course it's nice if each pass is
logically separate and does a single thing?
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32921