From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED.blaine.gmane.org!not-for-mail From: Alex Gramiak Newsgroups: gmane.emacs.devel Subject: Re: Using __builtin_expect (likely/unlikely macros) Date: Fri, 19 Apr 2019 08:45:27 -0600 Message-ID: <87h8au835k.fsf@gmail.com> References: <87a7gst973.fsf@gmail.com> <875zrgt12q.fsf@gmail.com> <6919a4c8-df76-ea1e-34db-1fa62a360e5a@cs.ucla.edu> <87h8aykdod.fsf@gmail.com> <4fa7885e-8c66-c7c4-ff71-a013505863af@cs.ucla.edu> <2dfb837d-989d-c736-b6e6-b20c0e940596@cs.ucla.edu> <87o956c4n4.fsf@gmail.com> <1fbd2fca-18f0-0a90-7a45-58419a9e11ee@cs.ucla.edu> <1555450070.23658.4@yandex.ru> <66b74701-012a-902e-4a5b-6bc30efa87c0@cs.ucla.edu> <1555682281.12550.3@yandex.ru> Mime-Version: 1.0 Content-Type: text/plain Injection-Info: blaine.gmane.org; posting-host="blaine.gmane.org:195.159.176.226"; logging-data="191926"; mail-complaints-to="usenet@blaine.gmane.org" User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.2 (gnu/linux) Cc: Paul Eggert , Stefan Monnier , emacs-devel@gnu.org To: Konstantin Kharlamov Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Fri Apr 19 16:46:07 2019 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([209.51.188.17]) by blaine.gmane.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:256) (Exim 4.89) (envelope-from ) id 1hHUmF-000noY-1k for ged-emacs-devel@m.gmane.org; Fri, 19 Apr 2019 16:46:07 +0200 Original-Received: from localhost ([127.0.0.1]:57461 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hHUmE-0007tH-3I for ged-emacs-devel@m.gmane.org; Fri, 19 Apr 2019 10:46:06 -0400 Original-Received: from eggs.gnu.org ([209.51.188.92]:34924) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hHUlg-0007t0-Ls for emacs-devel@gnu.org; Fri, 19 Apr 2019 10:45:33 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hHUle-0004jf-Nd for emacs-devel@gnu.org; Fri, 19 Apr 2019 10:45:32 -0400 Original-Received: from mail-pg1-x535.google.com ([2607:f8b0:4864:20::535]:37931) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1hHUle-0004ew-Ey for emacs-devel@gnu.org; Fri, 19 Apr 2019 10:45:30 -0400 Original-Received: by mail-pg1-x535.google.com with SMTP id j26so2764645pgl.5 for ; Fri, 19 Apr 2019 07:45:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:references:date:in-reply-to:message-id :user-agent:mime-version; bh=8Iu+CNJ6dAF+QtLuM6IrcEF8um3h23IykC2BuhsNySY=; b=E46MRABuk/MkaS32ZtgidTeugTfytVvupeXz2T+sR8FxHBH77D6KJFZIaI0TW9joLB jhPq+5rXg/K2OxqEaBBGo6UKkoyT7NkJmKWuevhoe/qgLmYm3iJexU+5uZqAbh7yefg+ UCfNss4hQbp+Zik9pNlnoCQT/FPeWJKM+LeqFKbq2Q0D/JnmmJXL6jbdmYwPDkP3snmW dw+x6awlu1vUIl8Sg+W+i3fOjeBs9LqdS1uRh9gdk4QonrPoMoWZIk1015JXrGJUMOs0 kkKB9f96M7eZEAld1a/3gZRLUurYEvvntOtifuoqBztJdZc8rgTPMo9feOwE+1xv3peQ cmOA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:references:date:in-reply-to :message-id:user-agent:mime-version; bh=8Iu+CNJ6dAF+QtLuM6IrcEF8um3h23IykC2BuhsNySY=; b=gIeIuF26lOSvblapAnas5Flpknpb4SIAHYjl8AUTHwLDNGfefb/VWkD6P7gQcIFozn fyaRdH89IhdaMiLRCKgoqZQy1QYFzWRVq86qFfwAu5HaD3LA52cXZe9ZNots+5CRWWbG f81nfvf/LAiNKOYHKe+NgNE6S4ZCcN/69UvqrvqP3R+8bF5Zjjfmzu27rxx7C44mUb3q hrXci/ppVlV4Xnd/RLCcQrxKfPEOoXoZ4rs/1/h1LJBoSgEbNRw1q1J7WXnO55x3x+yn RiuTxCoCsz47oasYROY8cuGJolvyqkPp6s1o1dU5uxlQG8sfJgLKaZp57wY3oh6L7ln9 p2bw== X-Gm-Message-State: APjAAAV4wHLoVQ//iEimAucg0SHqexzxBY0z6Nee1MjY11qblm+ZBQtP 2j8ZRlz637tGaOy59OeXNA+tlilV X-Google-Smtp-Source: APXvYqwQzDrNgC17AFFOhFfaITynZcNKF/NiH6V3HpIsUNFcvlaEonzx6uNsnNMVvc2DFi3QWrrQ6A== X-Received: by 2002:a63:af45:: with SMTP id s5mr4202567pgo.420.1555685126474; Fri, 19 Apr 2019 07:45:26 -0700 (PDT) Original-Received: from lylat ([2604:3d09:e37f:1500:1a72:4878:e793:7302]) by smtp.gmail.com with ESMTPSA id t12sm8752099pfl.59.2019.04.19.07.45.25 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Fri, 19 Apr 2019 07:45:25 -0700 (PDT) In-Reply-To: <1555682281.12550.3@yandex.ru> (Konstantin Kharlamov's message of "Fri, 19 Apr 2019 16:58:01 +0300") X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2607:f8b0:4864:20::535 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.org gmane.emacs.devel:235660 Archived-At: Konstantin Kharlamov writes: > The slowdown is to be expected, given that GCC devs said that "cold" produces > very inefficient code. I took his statement to mean that the code generated in cold branches are very inefficient. In this case that would refer to the obsolete/unused/error CASEs, which should not be getting called, so I don't believe the slowdown is to be expected.