From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugs-return-415396-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org>
Received: (qmail 30945 invoked by alias); 15 Feb 2013 10:21:31 -0000
Received: (qmail 30544 invoked by uid 48); 15 Feb 2013 10:20:54 -0000
From: "steven at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug rtl-optimization/56339] [4.8 Regression]: Suboptimal register allocation
Date: Fri, 15 Feb 2013 10:21:00 -0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: rtl-optimization
X-Bugzilla-Keywords: missed-optimization, ra
X-Bugzilla-Severity: normal
X-Bugzilla-Who: steven at gcc dot gnu.org
X-Bugzilla-Status: NEW
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: 4.8.0
X-Bugzilla-Changed-Fields:
Message-ID: <bug-56339-4-gbACmvKr17@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-56339-4@http.gcc.gnu.org/bugzilla/>
References: <bug-56339-4@http.gcc.gnu.org/bugzilla/>
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
Content-Type: text/plain; charset="UTF-8"
MIME-Version: 1.0
Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm
Precedence: bulk
List-Id: <gcc-bugs.gcc.gnu.org>
List-Archive: <http://gcc.gnu.org/ml/gcc-bugs/>
List-Post: <mailto:gcc-bugs@gcc.gnu.org>
List-Help: <mailto:gcc-bugs-help@gcc.gnu.org>
Sender: gcc-bugs-owner@gcc.gnu.org
X-SW-Source: 2013-02/txt/msg01561.txt.bz2


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56339

--- Comment #4 from Steven Bosscher <steven at gcc dot gnu.org> 2013-02-15 10:20:52 UTC ---
Perhaps for regmove IRA classes should be set up unconditionally:

Index: regmove.c
===================================================================
--- regmove.c   (revision 196074)
+++ regmove.c   (working copy)
@@ -1234,8 +1234,9 @@ regmove_optimize (void)
   regstat_init_n_sets_and_refs ();
   regstat_compute_ri ();

-  if (flag_ira_loop_pressure)
-    ira_set_pseudo_classes (true, dump_file);
+  /* Set up register classes for pseudos, so that reg_preferred_class
+     returns a more useful result.  */
+  ira_set_pseudo_classes (true, dump_file);

   regno_src_regno = XNEWVEC (int, nregs);
   for (i = nregs; --i >= 0; )
@@ -1256,8 +1257,7 @@ regmove_optimize (void)
     }
   regstat_free_n_sets_and_refs ();
   regstat_free_ri ();
-  if (flag_ira_loop_pressure)
-    free_reg_info ();
+  free_reg_info ();
   return 0;
 }