From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-00641c01.pphosted.com (mx0a-00641c01.pphosted.com [205.220.165.146]) by sourceware.org (Postfix) with ESMTPS id 42BAF385CCB0; Wed, 11 Oct 2023 21:53:37 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 42BAF385CCB0 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=gcc.gnu.org Authentication-Results: sourceware.org; spf=fail smtp.mailfrom=gcc.gnu.org Received: from pps.filterd (m0247472.ppops.net [127.0.0.1]) by mx0a-00641c01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 39BLhmDd016078; Wed, 11 Oct 2023 21:53:36 GMT Received: from mxout25.s.uw.edu (mxout25.s.uw.edu [140.142.234.175]) by mx0a-00641c01.pphosted.com (PPS) with ESMTPS id 3tp3388p6t-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 11 Oct 2023 21:53:35 +0000 Received: from smtp.washington.edu (smtp.washington.edu [128.208.60.132]) by mxout25.s.uw.edu (8.14.4+UW20.07/8.14.4+UW22.04) with ESMTP id 39BLr4kR025320 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 11 Oct 2023 14:53:04 -0700 X-Auth-Received: from kmatsui-ThinkPad-X1-Carbon-Gen-9.dhcp4.washington.edu ([10.19.18.191]) (authenticated authid=kmatsui) by smtp.washington.edu (8.16.1+UW21.10/8.14.4+UW19.10) with ESMTPSA id 39BLoq56021017 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 11 Oct 2023 14:53:04 -0700 X-UW-Orig-Sender: kmatsui@smtp.washington.edu From: Ken Matsui To: gcc-patches@gcc.gnu.org Cc: libstdc++@gcc.gnu.org, Ken Matsui Subject: [PATCH v17 04/39] libstdc++: Optimize is_const trait performance Date: Wed, 11 Oct 2023 14:45:40 -0700 Message-ID: <20231011215049.1052142-5-kmatsui@gcc.gnu.org> X-Mailer: git-send-email 2.42.0 In-Reply-To: <20231011215049.1052142-1-kmatsui@gcc.gnu.org> References: <20231010221520.3680267-1-kmatsui@gcc.gnu.org> <20231011215049.1052142-1-kmatsui@gcc.gnu.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Proofpoint-GUID: AE26oUhrRCObwvKhfZHRPvnN1pyJx1-o X-Proofpoint-ORIG-GUID: AE26oUhrRCObwvKhfZHRPvnN1pyJx1-o X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.267,Aquarius:18.0.980,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-10-11_17,2023-10-11_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=0 mlxscore=0 spamscore=0 adultscore=0 bulkscore=0 priorityscore=1501 impostorscore=0 phishscore=0 lowpriorityscore=0 malwarescore=0 clxscore=1034 mlxlogscore=837 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2309180000 definitions=main-2310110193 X-Spam-Status: No, score=-13.0 required=5.0 tests=BAYES_00,GIT_PATCH_0,JMQ_SPF_NEUTRAL,KAM_DMARC_STATUS,RCVD_IN_DNSWL_LOW,SPF_HELO_NONE,SPF_NEUTRAL,TXREP 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: This patch optimizes the performance of the is_const trait by dispatching to the new __is_const built-in trait. libstdc++-v3/ChangeLog: * include/std/type_traits (is_const): Use __is_const built-in trait. (is_const_v): Likewise. Signed-off-by: Ken Matsui --- libstdc++-v3/include/std/type_traits | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/libstdc++-v3/include/std/type_traits b/libstdc++-v3/include/std/type_traits index 677cd934b94..686e38e47c3 100644 --- a/libstdc++-v3/include/std/type_traits +++ b/libstdc++-v3/include/std/type_traits @@ -784,6 +784,12 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION // Type properties. /// is_const +#if _GLIBCXX_USE_BUILTIN_TRAIT(__is_const) + template + struct is_const + : public __bool_constant<__is_const(_Tp)> + { }; +#else template struct is_const : public false_type { }; @@ -791,6 +797,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION template struct is_const<_Tp const> : public true_type { }; +#endif /// is_volatile template @@ -3218,10 +3225,17 @@ template inline constexpr bool is_compound_v = is_compound<_Tp>::value; template inline constexpr bool is_member_pointer_v = is_member_pointer<_Tp>::value; + +#if _GLIBCXX_USE_BUILTIN_TRAIT(__is_const) +template + inline constexpr bool is_const_v = __is_const(_Tp); +#else template inline constexpr bool is_const_v = false; template inline constexpr bool is_const_v = true; +#endif + template inline constexpr bool is_volatile_v = false; template -- 2.42.0