From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 115200 invoked by alias); 23 Mar 2015 17:47:58 -0000 Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Received: (qmail 115190 invoked by uid 89); 23 Mar 2015 17:47:58 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.1 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_LOW,SPF_PASS autolearn=ham version=3.3.2 X-HELO: mail-ob0-f178.google.com Received: from mail-ob0-f178.google.com (HELO mail-ob0-f178.google.com) (209.85.214.178) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES128-GCM-SHA256 encrypted) ESMTPS; Mon, 23 Mar 2015 17:47:57 +0000 Received: by obcjt1 with SMTP id jt1so108630366obc.2 for ; Mon, 23 Mar 2015 10:47:55 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=UrZZAuh+0rfwxLm8yezsWB81Dir3TjgCWsnBseNeI50=; b=hKywhExTP4kwSt4+xQjypzJ33p5NnYzgtpS+v4WDO510awqGDDa4WJtW+KdbS5JW3X 5E3MtCWTNNDpsVtvhv0VXesDgxd7hppbnztlh+iTLEatyiyGzyO8+1dLFoAt8jZpBXzl rihwtXz3I1H7cYhq4LZsjdR93rD8PpLRWH7DAKVQOFfC5Pa0gWd6kjEmRn81GRyhJe6L QTfXbL5Lw34msYRxK1BycWgB6AxXzimAkCHPIH5aVgz1SELz7B0FIlrb/1lP4f819QGP jp2w43dnAE1OJLOyLtG6g3hTLfw//OPWiQPogXKrgVzzzSBLcLCSHYRbEVk0js+ZtWbc SRkw== X-Gm-Message-State: ALoCoQnOZmUn7H7Myw7293HH/xlKcFbtK+1KiGCZAi+L8/+qx0/YsV4rlYoV0F40RJlqJ9eXuOq6 MIME-Version: 1.0 X-Received: by 10.182.255.195 with SMTP id as3mr265919obd.56.1427132875248; Mon, 23 Mar 2015 10:47:55 -0700 (PDT) Received: by 10.202.54.66 with HTTP; Mon, 23 Mar 2015 10:47:55 -0700 (PDT) In-Reply-To: References: Date: Mon, 23 Mar 2015 17:47:00 -0000 Message-ID: Subject: Re: [PATCH, ARM, PR64208] LRA ICE Fix From: Yvan Roux To: Ramana Radhakrishnan Cc: "gcc-patches@gcc.gnu.org" , Ramana Radhakrishnan , Richard Earnshaw , Vladimir Makarov Content-Type: text/plain; charset=UTF-8 X-IsSubscribed: yes X-SW-Source: 2015-03/txt/msg01208.txt.bz2 Hi, On 23 March 2015 at 17:08, Ramana Radhakrishnan wrote: > On Wed, Mar 18, 2015 at 10:19 AM, Yvan Roux wrote: >> Hi, >> >> This is a fix for PR64208 where LRA loops when dealing with >> iwmmxt_arm_movdi insn. As explain in the PR, the issue was introduced >> on trunk and 4.9 branch by fix of PR rtl-optimization/60969 and then >> workaround by r211798 (-fuse-caller-save enable for ARM). >> >> The changes in IRA cost made by PR60969, changed the register class of >> this insn output from GENERAL_REGS to IWMMXT_REGS, and the >> redundancies in the insn pattern alternatives description force LRA to >> reload the pseudo, which generates the same iwmmxt_arm_movdi insn, >> which can't be resolved, and so on ... >> >> Removing the redundancies fixes the issue, as LRA find that >> alternative 8 (Uy => y) matches. >> >> This issue is present in 4.9 branch, but latent on trunk (the >> clobbering of IP and CC information added during -fuse-caller-save >> patch changed the register allocation). >> >> Cross compiled and regression tested on ARM targets (but not on an >> IWMMXT one), is it ok for trunk and 4.9 branch ? > > > This looks sane. It doesn't look reasonable for alternatives to be > duplicating each other. > > Given I have neither the time nor the hardware to test this patch on, > I'd rather someone with an interest in iwMMX possibly folks from > Marvell can pick up testing for this patch. Ok, Thanks Ramana, I'll wait for somebody able to test it. Notice, that without this patch on the 4.9 branch, building a cross compiler which default to iWMMXT architectures ICE on that during LRA while building of libgcc. Cheers, Yvan > regards > Ramana > >> >> Rq: I think that adding IP and CC clobbers to >> CALL_INSN_FUNCTION_USAGE, as specified by AAPCS, in 4.9 branch is >> something we need too, I've a patch for that if you agree on that. >> >> Thanks, >> Yvan >> >> 2105-03-17 Yvan Roux >> >> PR target/64208 >> * config/arm/iwmmxt.md ("*iwmmxt_arm_movdi"): Cleanup redundant >> alternatives.