From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E8BAAC76188 for ; Fri, 19 Jul 2019 03:25:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B3E9B21849 for ; Fri, 19 Jul 2019 03:25:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="uAzd3DTO" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726642AbfGSDZB (ORCPT ); Thu, 18 Jul 2019 23:25:01 -0400 Received: from mail-wr1-f66.google.com ([209.85.221.66]:40120 "EHLO mail-wr1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726055AbfGSDZB (ORCPT ); Thu, 18 Jul 2019 23:25:01 -0400 Received: by mail-wr1-f66.google.com with SMTP id r1so30709377wrl.7 for ; Thu, 18 Jul 2019 20:24:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=jIYPnkgBs5i86rbWUSwNdiw65NtG6kE0hp4IepPNimw=; b=uAzd3DTOad8sm8SbAbgLpLuIhEdXSKzEZq0uAVNPjjgfCGSTsFIK7uIaPbM+AILI1T JAvFnrZaC3ngiU7GDa/hEQeMeNf62aTdCJ+/2tou3cwabyOoq/c3eQ/8GQtN2xa9r/QT sO3MrrlkW6O4cJY1gi4NgKsLjlmNRdsQSf2bXYAtuZHNIYXLvrR+NuTJ6DebYT4mdRKZ AVujvuw0kIDZdVfrjhrlx0cnJs8IlapWBSMutWKM5GwfeHuzZ/hI//2duR/hsTNY7WcM zvbcqleNRVXUwGRmxYi6jv7nrMFYn3OF2YwOBRjzz6xER/YP8caUuLYdu5MwbHFCaXMg FwxA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=jIYPnkgBs5i86rbWUSwNdiw65NtG6kE0hp4IepPNimw=; b=uhxuBl6ypxGPmUJbEcBwNcXqS7T1rEdCQnjCwRAwxIMf/JuqslZygmGEgvfhggIwM8 RN7y1xWlkhwbJ7MSC/X26OwidSAf/zmlzV2C/ZJINzozmJLDNhRiiBWMVUWOT4UrMfBL XCV1GRbKaaonqdls2Uc+MfWjckUeBMbMjnt0ExeabNV4ikTXvCPnRLrakYo/reln+3Ad IphX95pKVxwKPG5TSiXTeOaz6enSKt5fARNJZlRyF8anj6UA8NUXr+dq5n1xkHe3p6+j 6x9fa3+//NqsqodhsCiMD3exy4aoPXHnwIShgGxHfVBMErCy+lbNijdM+/qC9oZOqkmb yYAA== X-Gm-Message-State: APjAAAW7yMVSWvs121++UTffTFjtN7xwnJ1M7yKWzF6eGtgZ/CtXRRkr Wle3P13mdZrCACn9z6jB1m8P5wd0+N8= X-Google-Smtp-Source: APXvYqyT8jgZuM/70vXITnsp6orU2Gbote6On0qrgGrBbjMKFgK5AbQwBSEInRvsJG2tx8AWq8pyaQ== X-Received: by 2002:adf:f883:: with SMTP id u3mr52455389wrp.0.1563506698857; Thu, 18 Jul 2019 20:24:58 -0700 (PDT) Received: from archlinux-threadripper ([2a01:4f8:222:2f1b::2]) by smtp.gmail.com with ESMTPSA id r14sm27007800wrx.57.2019.07.18.20.24.57 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Thu, 18 Jul 2019 20:24:58 -0700 (PDT) Date: Thu, 18 Jul 2019 20:24:56 -0700 From: Nathan Chancellor To: Christophe Leroy Cc: Michael Ellerman , Segher Boessenkool , Benjamin Herrenschmidt , Paul Mackerras , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com Subject: Re: [PATCH v2] powerpc: slightly improve cache helpers Message-ID: <20190719032456.GA14108@archlinux-threadripper> References: <45hnfp6SlLz9sP0@ozlabs.org> <20190708191416.GA21442@archlinux-threadripper> <20190709064952.GA40851@archlinux-threadripper> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190709064952.GA40851@archlinux-threadripper> User-Agent: Mutt/1.12.1 (2019-06-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 08, 2019 at 11:49:52PM -0700, Nathan Chancellor wrote: > On Tue, Jul 09, 2019 at 07:04:43AM +0200, Christophe Leroy wrote: > > Is that a Clang bug ? > > No idea, it happens with clang-8 and clang-9 though (pretty sure there > were fixes for PowerPC in clang-8 so something before it probably won't > work but I haven't tried). > > > > > Do you have a disassembly of the code both with and without this patch in > > order to compare ? > > I can give you whatever disassembly you want (or I can upload the raw > files if that is easier). > > Cheers, > Nathan Hi Christophe and Segher, What disassembly/files did you need to start taking a look at this? I can upload/send whatever you need. If it is easier, we have a self contained clang build script available to make it easier to reproduce this on your side (does assume an x86_64 host): https://github.com/ClangBuiltLinux/tc-build Cheers, Nathan