From patchwork Tue Dec 15 21:45:19 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: =?utf-8?q?Matthias_M=C3=A4nnich?= X-Patchwork-Id: 41428 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 063443858D29; Tue, 15 Dec 2020 21:45:28 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 063443858D29 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1608068728; bh=5Ogtb786wOtL0gK44FRimG0Lncxm6Zcs2vfSV+f6IGI=; h=Date:Subject:To:List-Id:List-Unsubscribe:List-Archive:List-Help: List-Subscribe:From:Reply-To:Cc:From; b=Zo0pxP0Mne1Sg5UnUMV98pAyoZOSBnjs91wNLWzyj+qWbtcddiXGAdaoCnNIU5WDp 8gsu+x0AU+IrKXOaqfgPaHjf13Aj6LI3SPYKVULxPzcz3DVU3clk1OoZjEPPnH2+u2 mX2nNmzyHCkDtNNWbMirZs6QdEn9ZQU/YmTz21lY= X-Original-To: libabigail@sourceware.org Delivered-To: libabigail@sourceware.org Received: from mail-qt1-x84a.google.com (mail-qt1-x84a.google.com [IPv6:2607:f8b0:4864:20::84a]) by sourceware.org (Postfix) with ESMTPS id 113CA3858D29 for ; Tue, 15 Dec 2020 21:45:25 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 113CA3858D29 Received: by mail-qt1-x84a.google.com with SMTP id v9so15289427qtw.12 for ; Tue, 15 Dec 2020 13:45:25 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:message-id:mime-version:subject:from :to:cc; bh=5Ogtb786wOtL0gK44FRimG0Lncxm6Zcs2vfSV+f6IGI=; b=lZMyl2svJ5UnqtpsV9t6LPmeJdyWWO4xBcwM9Xfq/efRFn8pVMe9TmMCiIAwlHnT0d yyrIzy+kBdYEaYIeFX9any9RwPjey6KMOoNPLCyEy+KSA5FpaFLgptzBBkKWp7Q1rF5a cOG6ShWr85/mx5qR67Aggl5RQ2vrvtdfEgUE0D+DHt4yprIyw4Zsl6b3DRsGvMUM7KsW TeNyV/07dPNrIz12wYQgNx9vUzX4JiVqmWifiFXe1OWFdIqOBpnnE/85i16coTOlphpB VceVxhV2fFZrsBpuDP7WU167PASRmTeSFbkW8RjJ7de4ejQyby6khQk+HtOf3YHCPt3S XaXw== X-Gm-Message-State: AOAM531MFT532D4oelMy+PaEHSzeTuEsl2EbAfPOHQh3EcAqtHn3BmW6 UDQQKymiAhAKARS5kKESem6pPITM5pH36cCz9OHXa0VGs1HeFqYYB2elt5XZm4mpm6QW7rhglwv 0fyy3hHkLFyh3SVwY1nCr3cgpvUtayAAnEY0RKpsj6cd/FUW18EIwA8qrYFNgjzEjhm03/K0= X-Google-Smtp-Source: ABdhPJxtkd2If0bIWRgKszM/SW4SOl4cSGE5SZiLL3/QZGKTDLwgRRZ/yeOz5A3/9RmLdIRjw6qqnyu+A+G5DQ== X-Received: from lux.lon.corp.google.com ([2a00:79e0:d:210:7220:84ff:fe09:a3aa]) (user=maennich job=sendgmr) by 2002:ad4:5be1:: with SMTP id k1mr34259778qvc.48.1608068724411; Tue, 15 Dec 2020 13:45:24 -0800 (PST) Date: Tue, 15 Dec 2020 21:45:19 +0000 Message-Id: <20201215214519.2992965-1-maennich@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.29.2.684.gfbc64c5ab5-goog Subject: [PATCH] abg-ir: Optimize calls to std::string::find() for a single char. To: libabigail@sourceware.org X-Spam-Status: No, score=-22.6 required=5.0 tests=BAYES_00, DKIMWL_WL_MED, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP, USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libabigail@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Mailing list of the Libabigail project List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-Patchwork-Original-From: Matthias Maennich via Libabigail From: =?utf-8?q?Matthias_M=C3=A4nnich?= Reply-To: Matthias Maennich Cc: maennich@google.com, kernel-team@android.com, Chris Kennelly Errors-To: libabigail-bounces@sourceware.org Sender: "Libabigail" This is a common micro optimization suggested by clang-tidy to improve string::find performance. I have not done any measurements as to how it impacts performance for that particular piece of code, but generally this overload is to prefer here. * src/abg-ir.cc (elf_symbol::get_name_and_version_from_id): use character literal overload for single character string::find. (parse_integral_type): Likewise. Suggested-by: Chris Kennelly Signed-off-by: Matthias Maennich --- src/abg-ir.cc | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/src/abg-ir.cc b/src/abg-ir.cc index 1a4091b9370c..e11af0fd5fee 100644 --- a/src/abg-ir.cc +++ b/src/abg-ir.cc @@ -2031,7 +2031,7 @@ elf_symbol::get_name_and_version_from_id(const string& id, { name.clear(), ver.clear(); - string::size_type i = id.find("@"); + string::size_type i = id.find('@'); if (i == string::npos) { name = id; @@ -2044,7 +2044,7 @@ elf_symbol::get_name_and_version_from_id(const string& id, if (i >= id.size()) return true; - string::size_type j = id.find("@", i); + string::size_type j = id.find('@', i); if (j == string::npos) j = i; else @@ -12926,7 +12926,7 @@ parse_integral_type(const string& type_name, while (cur_pos < len) { prev_pos = cur_pos; - cur_pos = input.find(" ", prev_pos); + cur_pos = input.find(' ', prev_pos); prev_word = cur_word; cur_word = input.substr(prev_pos, cur_pos - prev_pos); @@ -12940,7 +12940,7 @@ parse_integral_type(const string& type_name, && prev_word != "long") { prev_pos = cur_pos; - cur_pos = input.find(" ", prev_pos); + cur_pos = input.find(' ', prev_pos); string saved_prev_word = prev_word; prev_word = cur_word; cur_word = input.substr(prev_pos, cur_pos - prev_pos);