From patchwork Sun Feb 5 15:27:25 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Uros Bizjak X-Patchwork-Id: 139651 Return-Path: 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 8F7B21007D2 for ; Mon, 6 Feb 2012 02:27:45 +1100 (EST) Comment: DKIM? See http://www.dkim.org DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d=gcc.gnu.org; s=default; x=1329060466; h=Comment: DomainKey-Signature:Received:Received:Received:Received: MIME-Version:Received:Received:Date:Message-ID:Subject:From:To: Cc:Content-Type:Mailing-List:Precedence:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:Sender:Delivered-To; bh=LhQ9nE2 ZrXIScGtqhlV1kiT1oX4=; b=xXnoyM02s0KPBzFQH531U3LKhJePAW+PJeLNTp8 1B4z4K48TBZxZ3bTwCUJLEMLsMkvOTCSk6Am1rqyAtvIxqgJAwHyaHX2W6TGYW9K Vn+JwtU/0E0rE++oNk1ynxThigzz5Sjmcd2DySYkKfdoj0mUl4Lk0nWxx8xhTXfU dvZk= Comment: DomainKeys? See http://antispam.yahoo.com/domainkeys DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=default; d=gcc.gnu.org; h=Received:Received:X-SWARE-Spam-Status:X-Spam-Check-By:Received:Received:MIME-Version:Received:Received:Date:Message-ID:Subject:From:To:Cc:Content-Type:Mailing-List:Precedence:List-Id:List-Unsubscribe:List-Archive:List-Post:List-Help:Sender:Delivered-To; b=nixmM2zajIgsPaVeDjj1vWwFW0KkYTcbnnz2eAjwoHihO0YjeeydbY8HNjg0zt zbNeeEo2pzg4uCP8w8vYd+E0fSFgUHwSDnqsApu8cEzl0/GCCloVHAUAMQgvD+sF z8665nNkoAiQuHoZax65z1dThqRWCln9LhOAJ2mOBL7LI=; Received: (qmail 17682 invoked by alias); 5 Feb 2012 15:27:42 -0000 Received: (qmail 17664 invoked by uid 22791); 5 Feb 2012 15:27:41 -0000 X-SWARE-Spam-Status: No, hits=-2.3 required=5.0 tests=AWL, BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, FREEMAIL_FROM, RCVD_IN_DNSWL_LOW, TW_ZJ X-Spam-Check-By: sourceware.org Received: from mail-gx0-f175.google.com (HELO mail-gx0-f175.google.com) (209.85.161.175) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Sun, 05 Feb 2012 15:27:26 +0000 Received: by ggeq1 with SMTP id q1so2659700gge.20 for ; Sun, 05 Feb 2012 07:27:25 -0800 (PST) MIME-Version: 1.0 Received: by 10.101.185.1 with SMTP id m1mr6080609anp.21.1328455645434; Sun, 05 Feb 2012 07:27:25 -0800 (PST) Received: by 10.146.124.2 with HTTP; Sun, 5 Feb 2012 07:27:25 -0800 (PST) Date: Sun, 5 Feb 2012 16:27:25 +0100 Message-ID: Subject: [PATCH 4.8, i386]: Enable post-reload compare optimization pass (PR28685) From: Uros Bizjak To: gcc-patches@gcc.gnu.org Cc: Richard Henderson Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Delivered-To: mailing list gcc-patches@gcc.gnu.org Hello! Attached patch enables post-reload compare optimization pass for x86 targets. As shown in following test, patch removes redundant compare: --cut here-- int test(int a, int b) { int lt = a < b; int eq = a == b; if (lt) return 1; return eq; } --cut here-- gcc -O2 on x86_64, a cmove target: test: xorl %edx, %edx cmpl %esi, %edi movl $1, %eax sete %dl cmovge %edx, %eax ret gcc-O2 -fno-compare-elim: test: xorl %edx, %edx cmpl %esi, %edi movl $1, %eax sete %dl cmpl %esi, %edi cmovge %edx, %eax ret 2012-02-05 Uros Bizjak PR target/28685 * config/i386/i386.c (TARGET_FLAGS_REGNUM): New. testsuite/ChangeLog: PR target/28685 * gcc.target/i386/pr28685.c: New test. The patch was tested on x86_64-pc-linux-gnu {,-m32}. The patch will be committed to 4.8 once stage 1 opens. Uros. Index: config/i386/i386.c =================================================================== --- config/i386/i386.c (revision 183904) +++ config/i386/i386.c (working copy) @@ -38685,6 +38685,9 @@ #undef TARGET_EXPAND_TO_RTL_HOOK #define TARGET_EXPAND_TO_RTL_HOOK ix86_maybe_switch_abi +#undef TARGET_FLAGS_REGNUM +#define TARGET_FLAGS_REGNUM FLAGS_REG + #undef TARGET_LEGITIMATE_ADDRESS_P #define TARGET_LEGITIMATE_ADDRESS_P ix86_legitimate_address_p Index: testsuite/gcc.target/i386/pr28685.c =================================================================== --- testsuite/gcc.target/i386/pr28685.c (revision 0) +++ testsuite/gcc.target/i386/pr28685.c (revision 0) @@ -0,0 +1,12 @@ +/* { dg-options "-O2" } */ + +int test(int a, int b) +{ + int lt = a < b; + int eq = a == b; + if (lt) + return 1; + return eq; +} + +/* { dg-final { scan-assembler-times "cmp" 1 } } */