From: fanqifei <fanqifei@gmail.com>
To: Jim Wilson <wilson@codesourcery.com>
Cc: gcc@gcc.gnu.org
Subject: Re: constant hoisting out of loops
Date: Thu, 18 Mar 2010 17:10:00 -0000 [thread overview]
Message-ID: <f94afa701003181006r761ca89r547e0ad4338f78c@mail.gmail.com> (raw)
In-Reply-To: <1268850652.2587.9.camel@localhost>
On Thu, Mar 18, 2010 at 2:30 AM, Jim Wilson <wilson@codesourcery.com> wrote:
> On Wed, 2010-03-17 at 11:27 +0800, fanqifei wrote:
>> You are correct. The reload pass emitted the clr.w insn.
>> However, I can see loop opt passes after reload:
>> problem1.c.174r.loop2_invariant1
>
> Not unless you have a modified toolchain. We don't run loop opt after
> register allocation. See the list of optimization passes in the FSF GCC
> passes.c file. loop2 occurs before ira/postreload. If you do have a
> modified toolchain, then I doubt that the current loop passes would work
> right, since they were designed to handle pseudo-regs not hard-regs.
>
> Jim
>
>
>
That passes were added by me more than two months ago. I thought these
passes could perform the optimization of hoisting constant out of
loop.
I just removed them. Thanks very much for your help!
Now I am working on the movsi expander.
--
-Qifei Fan
http://freshtime.org
next prev parent reply other threads:[~2010-03-18 17:06 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-03-11 6:48 fanqifei
2010-03-14 21:39 ` Jim Wilson
2010-03-17 12:55 ` fanqifei
2010-03-17 19:16 ` Jim Wilson
2010-03-18 17:10 ` fanqifei [this message]
[not found] ` <f94afa701003190704l6a8a97bfs66817322dc1eb8f7@mail.gmail.com>
2010-03-19 14:51 ` Fwd: " fanqifei
2010-03-19 22:30 ` Jim Wilson
2010-03-20 16:40 ` fanqifei
2010-03-20 19:40 ` Jim Wilson
2010-03-20 19:44 ` fanqifei
2010-03-21 10:42 ` Jim Wilson
2010-03-21 22:46 ` fanqifei
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