From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm1-x32e.google.com (mail-wm1-x32e.google.com [IPv6:2a00:1450:4864:20::32e]) by sourceware.org (Postfix) with ESMTPS id 30111385840F for ; Thu, 5 Jan 2023 14:49:55 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 30111385840F Authentication-Results: sourceware.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=google.com Received: by mail-wm1-x32e.google.com with SMTP id ay40so28227053wmb.2 for ; Thu, 05 Jan 2023 06:49:55 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=TDh4iEeOaQsM6l5XMk05N983EHVLh+cLKdnfV26xO6Q=; b=Xk4npFTa2vOVH/Y6Aw9lyxT9ZY2fGcr1+U0Ye+s9ztG4OzM9au75bd0r5Pq4cRaJuL 8vf01vh22895FqooYUmIHAhMIMSUq4bg/PBrGHcvu+TD45CM1rD29BsnaRixQ0fAmCd4 yNgDmt6q7Maz2BovZbjmsHlV9oZYptnOKvrasqctrQzv7RHhS/9tgCmXp198arxizEcM G+6P4rcX4w6n20oe8wEawMxxI8NKPUyQQnE8vSp5ajS/XXJ2WbvcPoRJc/e7O81E+VYT we4UDxfToxd9QXT5VwKhHgv8mL26VoP/gN7HtTTzrXhu+vtFnt0OrOomTQ680pX5EhCV KFNA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=TDh4iEeOaQsM6l5XMk05N983EHVLh+cLKdnfV26xO6Q=; b=BimbVkp6nqdAMyn+UeEuFeiSN7oKrVpr6fCsyUyhyeDwMqyvy5UC8s8GMo0133oT1O 2f5jLERFpN00K+6TO1WlLukRTr1/jtq3aCZvVwUWzSL2jO8FIw9fNKayqrROI9T5rXne ERf9Obkpr5wSxbLQ6spAtKPI8TAJ2RLobxNSusG/SAu3G9IH1Etm4HY/kAcXkyWMNo8t NtgoWE4Zn4bxaRAtla669pVmkCfLSmYtV3QXfkSEbpDk+VLIoWRCiCyw6enWk9orF7Ue c5RzLBgwYpcvSH8DwYmI6SG5kXLpmB0dHaDgqkNLq1Jc5B1dmy2wBLq0JYG3ErxVHktr tkiQ== X-Gm-Message-State: AFqh2kqRXpzGFLN9aN0LmlFx7WFyAG1TrawywZ28EeOXHvkTdNnrebvs +enlM/GuTWfMoXlYpLAaAXjk4dloEcgNry+vetzWaA== X-Google-Smtp-Source: AMrXdXtWCh3/Yg59oalMIBQtJSeANSV7x5yiyPa4GMCd/ZRAMbXqMhKgUM+0VyD+DBzVf8C6QnFNFLPRHIaUV89lvx8= X-Received: by 2002:a05:600c:1c92:b0:3d9:6c7d:ca0e with SMTP id k18-20020a05600c1c9200b003d96c7dca0emr2521285wms.200.1672930193931; Thu, 05 Jan 2023 06:49:53 -0800 (PST) MIME-Version: 1.0 References: <83h6xugc5v.fsf@gnu.org> <835ye7e9jw.fsf@gnu.org> <87h6xrks77.fsf@tromey.com> <83mt7idacj.fsf@gnu.org> <87fsd4elb2.fsf@tromey.com> <83o7rs4qmg.fsf@gnu.org> <87cz84dasj.fsf@tromey.com> <835ydw20bw.fsf@gnu.org> <87wn6bbi5m.fsf@tromey.com> <83sfgz8m9i.fsf@gnu.org> <87o7rnb0ya.fsf@tromey.com> <83a6368chf.fsf@gnu.org> <87k02aaxc8.fsf@tromey.com> <83wn6a6n21.fsf@gnu.org> <587b899f-0f93-530a-7313-d4e1f9e501b9@simark.ca> <835ydt6jzw.fsf@gnu.org> <83wn63z81w.fsf@gnu.org> <46d7fd4b-d5f0-0007-3e88-20345e0e0584@simark.ca> <831qoayxuu.fsf@gnu.org> <878rii9bg3.fsf@tromey.com> <83fscpxxom.fsf@gnu.org> In-Reply-To: <83fscpxxom.fsf@gnu.org> From: Christian Biesinger Date: Thu, 5 Jan 2023 09:49:14 -0500 Message-ID: Subject: Re: Two observations using GDB 13 snapshot To: Eli Zaretskii Cc: Tom Tromey , simark@simark.ca, gdb-patches@sourceware.org, luis.machado@arm.com Content-Type: text/plain; charset="UTF-8" X-Spam-Status: No, score=-18.0 required=5.0 tests=BAYES_00,DKIMWL_WL_MED,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,ENV_AND_HDR_SPF_MATCH,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS,TXREP,USER_IN_DEF_DKIM_WL,USER_IN_DEF_SPF_WL autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: On Thu, Jan 5, 2023 at 2:11 AM Eli Zaretskii wrote: > > > From: Tom Tromey > > Cc: Simon Marchi , cbiesinger@google.com, > > tom@tromey.com, gdb-patches@sourceware.org, luis.machado@arm.com > > Date: Wed, 04 Jan 2023 15:33:48 -0700 > > > > >>>>> "Eli" == Eli Zaretskii writes: > > > > Eli> Looks like indeed strcasecmp is the culprit. With the patch below, > > Eli> which replaces strcasecmp with a simple case-insensitive comparison > > Eli> that only works with ASCII, the phase of reading symbols from gdb.exe > > Eli> goes down to just 6 seconds, which is basically the same time as with > > Eli> GDB 12. > > > > Thank you. Hopefully the other patch I have pending, which does > > something similar, should have the same effect. > > Thanks, I applied that patch (modulo the testsuite parts), and I can > confirm that it is almost as fast as the simple one I posted before: > 7.5 sec vs 6.2 sec to read the symbols from gdb.exe. > > However, what does this change mean in terms of GDB's support for > symbols with non-ASCII names? AFAIU, libiberty's TOLOWER only handles > ASCII characters. > > If it's okay for GDB to compare case-insensitively only ASCII > characters, then is the above patch mature enough to go to the gdb-13 > branch? If https://itanium-cxx-abi.github.io/cxx-abi/abi.html#mangle.name is up-to-date (?), then "This ABI does not yet specify a mangling for identifiers containing characters outside of _A-Za-z0-9." On the other hand, if https://rust-lang.github.io/rfcs/2603-rust-symbol-name-mangling-v0.html#punycode-vs-utf-8 is to be believed, GCC/Clang/MSVC do use UTF-8 for symbol names. But I don't think strcasecmp on Windows uses UTF-8? Christian