From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 31710 invoked by alias); 10 Jan 2008 20:15:25 -0000 Received: (qmail 31381 invoked by uid 48); 10 Jan 2008 20:14:42 -0000 Date: Thu, 10 Jan 2008 22:19:00 -0000 Message-ID: <20080110201442.31380.qmail@sourceware.org> X-Bugzilla-Reason: CC References: Subject: [Bug tree-optimization/34683] SSA rewriting in the loop unroller causes quadratic behavior In-Reply-To: Reply-To: gcc-bugzilla@gcc.gnu.org To: gcc-bugs@gcc.gnu.org From: "jaydub66 at gmail dot com" Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-bugs-owner@gcc.gnu.org X-SW-Source: 2008-01/txt/msg00962.txt.bz2 ------- Comment #45 from jaydub66 at gmail dot com 2008-01-10 20:14 ------- (In reply to comment #42) > This is probably all we can get for now - maybe another few % with minor > tweaks, > but nothing earth-shattering. After all, we _do_ have a much larger IL due > to the number of VOPs not partitioned. Well, it may not be earth-shattering, but it's still a solid improvement - of more than a few %! With rev. 131446 I get the following numbers: -O1 -fstrict-aliasing: 11sec, 201825 kB -O2: 22sec, 392166 kB -O3: 24sec, 388802 kB Compile time is reduced by a factor of 4 for -O2, and memory usage is halved for -O1! Nice job, Richard. So I'd say compile time really isn't an issue any more. But memory consumption is still a factor of 10 above what it was last year. Most of that comes from 'tree FRE' (~140MB), but all the junk in 'tree operand scan' is gone. For -O2 and -O3 another large chunk appears in 'tree PRE' (~160MB). Are you sure you want to close this bug? For me memory consumption is still an issue, and I would really like to see this fixed at some point. And if there is another bug which is a duplicate of this, could you point me to it? -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34683