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Subject: [Bug rtl-optimization/46556] Code size regression in struct access
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46556

--- Comment #5 from rguenther at suse dot de <rguenther at suse dot de> 2010-11-22 11:15:01 UTC ---
On Mon, 22 Nov 2010, amodra at gmail dot com wrote:

> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=46556
> 
> --- Comment #4 from Alan Modra <amodra at gmail dot com> 2010-11-22 10:47:24 UTC ---
> But within a loop gcc-4.2 looked quite reasonable too..

Of course.

> Don't we have a pass ordering problem if fwprop is to rewrite addresses?  We
> currently have cse1, fwprop1, loop passes, cse2, fwprop2.

Well, fwprop was only a suggestion (I can't think of something better
right now, maybe apart from expand (ugh), or better a pattern recognizer
before expand).

We really can't rely on expression canonicalization fold does for
addressing mode selection.  We have to do this somewhere else
(and IVOPTs does it for code inside loops).