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From: "kkojima at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/50749] SH Target: Post-increment addressing used only for first memory access
Date: Sun, 30 Oct 2011 23:37:00 -0000	[thread overview]
Message-ID: <bug-50749-4-m8RYGBuG13@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-50749-4@http.gcc.gnu.org/bugzilla/>

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50749

--- Comment #7 from Kazumoto Kojima <kkojima at gcc dot gnu.org> 2011-10-30 23:36:27 UTC ---
(In reply to comment #6)
> I wonder whether there might be something in the target code that suggests the
> early optimizers to do that?  I've tried playing with the TARGET_ADDRESS_COST
> hook but it didn't have any effect in this case.

-ftree-dump-all shows that forward propagation on ssa trees makes
those memory accesses into simple array accesses.  You can try
-fno-tree-forwprop and see the effect of that option.
It seems that there are no special knobs to control forwprop from
the target side.
The problem is that SH target can't do those simple array accesses
well at QI/HImode because of the lack of displacement addressing
for those modes.


  parent reply	other threads:[~2011-10-30 23:37 UTC|newest]

Thread overview: 23+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-10-16 20:29 [Bug target/50749] New: " oleg.endo@t-online.de
2011-10-16 23:34 ` [Bug target/50749] " kkojima at gcc dot gnu.org
2011-10-17  0:33 ` kkojima at gcc dot gnu.org
2011-10-19  0:00 ` oleg.endo@t-online.de
2011-10-19 21:37 ` kkojima at gcc dot gnu.org
2011-10-30 12:37 ` oleg.endo@t-online.de
2011-10-30 13:54 ` oleg.endo@t-online.de
2011-10-30 23:37 ` kkojima at gcc dot gnu.org [this message]
2011-11-28 22:54 ` oleg.endo@t-online.de
2011-11-29  0:25 ` kkojima at gcc dot gnu.org
2011-12-30  2:14 ` oleg.endo@t-online.de
2011-12-30  3:36 ` kkojima at gcc dot gnu.org
2012-06-12  7:10 ` [Bug middle-end/50749] Auto-inc-dec does not find subsequent contiguous mem accesses olegendo at gcc dot gnu.org
2012-08-23 14:17 ` [Bug rtl-optimization/50749] " olegendo at gcc dot gnu.org
2013-06-22 12:22 ` olegendo at gcc dot gnu.org
2013-09-30  9:06 ` amker.cheng at gmail dot com
2013-10-03 10:47 ` olegendo at gcc dot gnu.org
2013-12-06 20:28 ` olegendo at gcc dot gnu.org
2013-12-24 22:55 ` steven at gcc dot gnu.org
2015-05-22 13:57 ` olegendo at gcc dot gnu.org
2015-09-17  9:00 ` urjaman at gmail dot com
2015-09-17 14:26 ` olegendo at gcc dot gnu.org
2015-09-17 19:45 ` urjaman at gmail dot com

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