From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 42756 invoked by alias); 12 Aug 2019 13:35:47 -0000 Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-owner@gcc.gnu.org Received: (qmail 42748 invoked by uid 89); 12 Aug 2019 13:35:46 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-4.6 required=5.0 tests=AWL,BAYES_00,SPF_HELO_PASS autolearn=ham version=3.3.1 spammy=sk:micro-c, 24bit, fira-verbose, firaverbose X-HELO: mx1.redhat.com Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Mon, 12 Aug 2019 13:35:45 +0000 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 30223981B1; Mon, 12 Aug 2019 13:35:44 +0000 (UTC) Received: from [10.10.120.77] (ovpn-120-77.rdu2.redhat.com [10.10.120.77]) by smtp.corp.redhat.com (Postfix) with ESMTP id DB3A76F98E; Mon, 12 Aug 2019 13:35:42 +0000 (UTC) Subject: Re: Indirect memory addresses vs. lra To: John Darrington Cc: Jeff Law , Segher Boessenkool , Paul Koning , gcc@gcc.gnu.org References: <20190804191822.x4hwnfcyplnto3xc@jocasta.intra> <2B3A4EAB-D69E-4714-8FC4-C25E36B07BFF@comcast.net> <20190808172102.GH31406@gate.crashing.org> <2EEBCFAE-FF25-4664-AA5F-B3299CEA3CB1@comcast.net> <20190808191914.GK31406@gate.crashing.org> <20190809081439.baoyu3ii5i2qfbzt@jocasta.intra> <70b9bcc9-e12a-78b4-b8cc-a67b7ca3d38d@redhat.com> <20190810060553.m6e42sovw7s4xqoa@jocasta.intra> From: Vladimir Makarov Message-ID: <2bc558f1-9388-ec8e-b308-75f0f4041709@redhat.com> Date: Mon, 12 Aug 2019 13:35:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.7.0 MIME-Version: 1.0 In-Reply-To: <20190810060553.m6e42sovw7s4xqoa@jocasta.intra> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit X-IsSubscribed: yes X-SW-Source: 2019-08/txt/msg00094.txt.bz2 On 2019-08-10 2:05 a.m., John Darrington wrote: > On Fri, Aug 09, 2019 at 01:34:36PM -0400, Vladimir Makarov wrote: > > If you provide LRA dump for such test (it is better to use > -fira-verbose=15 to output full RA info into stderr), I probably could > say more. > > I've attached such a dump (generated from gcc/testsuite/gcc.c-torture/compile/pr53410-2.c). Unfortunately, this info is not enough for me to say what is the problem.  I only found suspicious that LRA is trying to assign a few registers to a pseudo register and fails even though these registers are not assigned to anything.  Probably HARD_REGNO_MODE_OK prevents this.  So it would be interesting to know how many registers of Pmode are actually available. In any case I'll try to look at this problem more on this week using your built gcc on gcc135. > > The less regs the architecture has, thoke easier to run into such error > message if something described wrong in the back-end.?? I see your > architecture is 16-bit micro-controller with only 8 regs, some of them is > specialized.?? So your architecture is really register constrained. > > That's not quite correct. It is a 24-bit micro-controller (the address > space is 24 bits wide). There are 2 address registers (plus stack > pointer and program counter) and there are 8 general purpose data > registers (of differing sizes). > >