Patchwork Add FRE pass to the early optimization pipeline

March 23, 2011, 2:17 p.m.

For quite some releases we'd wanted some (memory) CSE optimization
during early opts.  Currently we rely heavily on SRA which doesn't
always fulfill the "make code only smaller" promises which is
what early opts should do to improve precision of function size
estimates and to improve abstraction removal by early inlining.

Thus, this patch finally adds an early FRE pass at a suitable place.

The patch was sitting on pretty-ipa branch for some while now
and there were no noticeable issues with it there.

The patch disables FRE for the matrix-reorg testsuite - the
matrix reorg implementation is incredibly fragile with respect
to IL matching.  It also isn't useful anymore as it relies on
-fwhole-program but isn't prepared to work together with LTO,
so it at most works on single translation-unit units.  There is
no sign of anyone maintaining this code, but eventual removal
similar to struct-reorg should be handled separately from this patch.

Bootstrapped and tested on x86_64-unknown-linux-gnu (with the stdarg
patch applied).

Richard.

2011-02-23  Richard Guenther  <rguenther@suse.de>

	* passes.c (init_optimization_passes): Add FRE pass after
	early SRA.

	* gcc.dg/matrix/matrix.exp: Disable FRE.

Index: gcc/passes.c
===================================================================
*** gcc/passes.c.orig	2011-03-23 14:52:09.000000000 +0100
--- gcc/passes.c	2011-03-23 14:55:34.000000000 +0100
*************** init_optimization_passes (void)
*** 762,767 ****
--- 762,768 ----
  	     locals into SSA form if possible.  */
  	  NEXT_PASS (pass_build_ealias);
  	  NEXT_PASS (pass_sra_early);
+ 	  NEXT_PASS (pass_fre);
  	  NEXT_PASS (pass_copy_prop);
  	  NEXT_PASS (pass_merge_phi);
  	  NEXT_PASS (pass_cd_dce);
Index: gcc/testsuite/gcc.dg/matrix/matrix.exp
===================================================================
*** gcc/testsuite/gcc.dg/matrix/matrix.exp.orig	2011-01-10 12:29:56.000000000 +0100
--- gcc/testsuite/gcc.dg/matrix/matrix.exp	2011-03-23 15:08:04.000000000 +0100
***************
*** 20,26 ****
  load_lib gcc-dg.exp
  load_lib target-supports.exp

! set DEFAULT_MATCFLAGS "-O3 -fipa-matrix-reorg -fdump-ipa-matrix-reorg -fwhole-program"

  # Initialize `dg'.
  dg-init
--- 20,26 ----
  load_lib gcc-dg.exp
  load_lib target-supports.exp

! set DEFAULT_MATCFLAGS "-O3 -fipa-matrix-reorg -fdump-ipa-matrix-reorg -fwhole-program -fno-tree-fre"

  # Initialize `dg'.
  dg-init
*************** load_lib profopt.exp
*** 52,59 ****
  # These are globals used by profopt-execute.  The first is options
  # needed to generate profile data, the second is options to use the
  # profile data.
! set profile_option "-fprofile-generate -O3"
! set feedback_option "-fprofile-use -fipa-matrix-reorg -fdump-ipa-matrix-reorg -O3 -fwhole-program"

  foreach src [lsort [glob -nocomplain $srcdir/$subdir/transpose-*.c]] {
      # If we're only testing specific files and this isn't one of them, skip it.
--- 52,59 ----
  # These are globals used by profopt-execute.  The first is options
  # needed to generate profile data, the second is options to use the
  # profile data.
! set profile_option "-fprofile-generate -O3 -fno-tree-fre"
! set feedback_option "-fprofile-use -fipa-matrix-reorg -fdump-ipa-matrix-reorg -O3 -fwhole-program -fno-tree-fre"

  foreach src [lsort [glob -nocomplain $srcdir/$subdir/transpose-*.c]] {
      # If we're only testing specific files and this isn't one of them, skip it.

2011-02-23  Richard Guenther  <rguenther@suse.de>

	* gcc.dg/torture/pta-structcopy-1.c: Scan ealias dump, force
	foo to be inlined even at -O1.
	* gcc.dg/tree-ssa/ssa-dce-4.c: Disable FRE.
	* gcc.dg/ipa/ipa-pta-14.c: Likewise.
	* gcc.dg/tree-ssa/ssa-fre-1.c: Adjust.

Submitter	Richard Guenther
Date	March 23, 2011, 2:17 p.m.
Message ID	<alpine.LNX.2.00.1103231511290.810@zhemvz.fhfr.qr>
Download	mbox \| patch
Permalink	/patch/88084/
State	New
Headers	show Return-Path: <gcc-patches-return-287576-incoming=patchwork.ozlabs.org@gcc.gnu.org> X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from sourceware.org (server1.sourceware.org [209.132.180.131]) by ozlabs.org (Postfix) with SMTP id F1C8CB6F7A for <incoming@patchwork.ozlabs.org>; Thu, 24 Mar 2011 01:19:06 +1100 (EST) Received: (qmail 12907 invoked by alias); 23 Mar 2011 14:18:49 -0000 Received: (qmail 12748 invoked by uid 22791); 23 Mar 2011 14:18:19 -0000 X-SWARE-Spam-Status: No, hits=-4.4 required=5.0 tests=AWL, BAYES_50, RCVD_IN_DNSWL_HI, TW_CV, TW_FW, T_FRT_FREE, T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from cantor.suse.de (HELO mx1.suse.de) (195.135.220.2) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Wed, 23 Mar 2011 14:17:51 +0000 Received: from relay2.suse.de (charybdis-ext.suse.de [195.135.221.2]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.suse.de (Postfix) with ESMTP id 9F3F8945D6 for <gcc-patches@gcc.gnu.org>; Wed, 23 Mar 2011 15:17:47 +0100 (CET) Date: Wed, 23 Mar 2011 15:17:47 +0100 (CET) From: Richard Guenther <rguenther@suse.de> To: gcc-patches@gcc.gnu.org Subject: [PATCH] Add FRE pass to the early optimization pipeline Message-ID: <alpine.LNX.2.00.1103231511290.810@zhemvz.fhfr.qr> User-Agent: Alpine 2.00 (LNX 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: <gcc-patches.gcc.gnu.org> List-Unsubscribe: <mailto:gcc-patches-unsubscribe-incoming=patchwork.ozlabs.org@gcc.gnu.org> List-Archive: <http://gcc.gnu.org/ml/gcc-patches/> List-Post: <mailto:gcc-patches@gcc.gnu.org> List-Help: <mailto:gcc-patches-help@gcc.gnu.org> Sender: gcc-patches-owner@gcc.gnu.org Delivered-To: mailing list gcc-patches@gcc.gnu.org

Patchwork Add FRE pass to the early optimization pipeline

Comments

Patch