From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-40131.protonmail.ch (mail-40131.protonmail.ch [185.70.40.131]) by sourceware.org (Postfix) with ESMTPS id 9AAFE3858D20; Sun, 22 Sep 2024 19:08:28 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 9AAFE3858D20 Authentication-Results: sourceware.org; dmarc=pass (p=quarantine dis=none) header.from=protonmail.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=protonmail.com ARC-Filter: OpenARC Filter v1.0.0 sourceware.org 9AAFE3858D20 Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=185.70.40.131 ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1727032110; cv=none; b=hI5sXpTU5ZIScRHNhsXhEvCdox8XlGUTtuj+5qjqVqITP5LVMNBMPgl2ucSwdg3XMS23Gr1YgplE1AqGcsaK7aG14JB2pw0DrfijKcXEPE7RAOi8D2XZzc/X7PKuUOf5LOW+Qa18/AvGJwlD8egPYQ5BzvGhbKP5zi08ebgGdAA= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1727032110; c=relaxed/simple; bh=D86vA/4RD4S+7fY5EdN1tFPGlDPytIOlnDHAXkj1lUw=; h=DKIM-Signature:Date:To:From:Subject:Message-ID:MIME-Version; b=FOWORIvGhcD8ppXfIHii1Ry2ZtZ0CRHh+xhFQvS4Jug4hwLRvx9RXD9EW9ecBgjChHSuZy5ynJOkTL6ptsX4t5H3R6Ee4Ln/Q0ZiEIktCVbW330UiH18HgrRRX5HkleHGzB/yi8MpupIKNEN6aQKWddCACljkKOtfEtmemem43s= ARC-Authentication-Results: i=1; server2.sourceware.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=protonmail.com; s=protonmail3; t=1727032106; x=1727291306; bh=2G+EPbhS62n4weaHjUOaKfiblFXPrxFgjEU2xMZAScU=; h=Date:To:From:Cc:Subject:Message-ID:In-Reply-To:References: Feedback-ID:From:To:Cc:Date:Subject:Reply-To:Feedback-ID: Message-ID:BIMI-Selector; b=LEafrpiJBQ9Riy9BtesEnWLbg6iW8H2iJVI5IZOReg2dqE2hDixsQKFGwrKX6k8Ej nzsIUX1uEHh8CESKF7+hDg9WvRTxNRkf1HWz+4hvOnvTtbM53erVseoqXJ0SUUnaEK 6CsnAahPFhn+Pq0RbNK7bvBzL+7/PGqVTKvq0LJkpoaqUj/ygtC+ZgsCIDL/k/oGoa 2tS+ilmavkIJEbxB8mXXZKoB1qxudHx3uAw0dgwNA7HH5lKgLsyrDD+rk/gIdd3TQ4 rjoUsF41cJmOCKqzVgvGepLV3LFYVvjV11gfe2sGzjqu68Imn42uT0x3zcIOs06VgB ILC0NvhBQ/oog== Date: Sun, 22 Sep 2024 19:08:22 +0000 To: Jonathan Wakely From: =?utf-8?Q?Barnab=C3=A1s_P=C5=91cze?= Cc: libstdc++@gcc.gnu.org, gcc-patches@gcc.gnu.org Subject: Re: [PATCH v1] libstdc++: Optimize removal from unique assoc containers [PR112934] Message-ID: In-Reply-To: References: <20240311233548.3705328-1-pobrn@protonmail.com> Feedback-ID: 20568564:user:proton X-Pm-Message-ID: 31f852d47e772fe03667f1f13591447bb2b7f748 MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-11.2 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM,GIT_PATCH_0,RCVD_IN_MSPIKE_H3,RCVD_IN_MSPIKE_WL,SPF_HELO_PASS,SPF_PASS,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: Hi Jonathan It seems this patch got stuck, is there any chance it could be ultimately a= ccepted or rejected some time in the future? Regards, Barnab=C3=A1s P=C5=91cze 2024. m=C3=A1rcius 13., szerda 12:43 keltez=C3=A9ssel, Jonathan Wakely =C3=ADrta: > On Mon, 11 Mar 2024 at 23:36, Barnab=C3=A1s P=C5=91cze wrote: > > > > Previously, calling erase(key) on both std::map and std::set > > would execute that same code that std::multi{map,set} would. > > However, doing that is unnecessary because std::{map,set} > > guarantee that all elements are unique. > > > > It is reasonable to expect that erase(key) is equivalent > > or better than: > > > > auto it =3D m.find(key); > > if (it !=3D m.end()) > > m.erase(it); > > > > However, this was not the case. Fix that by adding a new > > function _Rb_tree<>::_M_erase_unique() that is essentially > > equivalent to the above snippet, and use this from both > > std::map and std::set. >=20 > Hi, this change looks reasonable, thanks for the patch. Please note > that GCC is currently in "stage 3" of its dev process so this change > would have to wait until after GCC 14 branches from trunk, due in a > few weeks. >=20 > I assume you ran the testsuite with no regressions. Do you have > benchmarks to show this making a difference? >=20 >=20 > > > > libstdc++-v3/ChangeLog: > > > > PR libstdc++/112934 > > * include/bits/stl_tree.h (_Rb_tree<>::_M_erase_unique): Add. > > * include/bits/stl_map.h (map<>::erase): Use _M_erase_unique. > > * include/bits/stl_set.h (set<>::erase): Likewise. > > --- > > libstdc++-v3/include/bits/stl_map.h | 2 +- > > libstdc++-v3/include/bits/stl_set.h | 2 +- > > libstdc++-v3/include/bits/stl_tree.h | 17 +++++++++++++++++ > > 3 files changed, 19 insertions(+), 2 deletions(-) > > > > diff --git a/libstdc++-v3/include/bits/stl_map.h b/libstdc++-v3/include= /bits/stl_map.h > > index ad58a631af5..229643b77fd 100644 > > --- a/libstdc++-v3/include/bits/stl_map.h > > +++ b/libstdc++-v3/include/bits/stl_map.h > > @@ -1115,7 +1115,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER > > */ > > size_type > > erase(const key_type& __x) > > - { return _M_t.erase(__x); } > > + { return _M_t._M_erase_unique(__x); } > > > > #if __cplusplus >=3D 201103L > > // _GLIBCXX_RESOLVE_LIB_DEFECTS > > diff --git a/libstdc++-v3/include/bits/stl_set.h b/libstdc++-v3/include= /bits/stl_set.h > > index c0eb4dbf65f..51a1717ec62 100644 > > --- a/libstdc++-v3/include/bits/stl_set.h > > +++ b/libstdc++-v3/include/bits/stl_set.h > > @@ -684,7 +684,7 @@ _GLIBCXX_BEGIN_NAMESPACE_CONTAINER > > */ > > size_type > > erase(const key_type& __x) > > - { return _M_t.erase(__x); } > > + { return _M_t._M_erase_unique(__x); } > > > > #if __cplusplus >=3D 201103L > > // _GLIBCXX_RESOLVE_LIB_DEFECTS > > diff --git a/libstdc++-v3/include/bits/stl_tree.h b/libstdc++-v3/includ= e/bits/stl_tree.h > > index 6f470f04f6a..9e80d449c7e 100644 > > --- a/libstdc++-v3/include/bits/stl_tree.h > > +++ b/libstdc++-v3/include/bits/stl_tree.h > > @@ -1225,6 +1225,9 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION > > size_type > > erase(const key_type& __x); > > > > + size_type > > + _M_erase_unique(const key_type& __x); > > + > > #if __cplusplus >=3D 201103L > > // _GLIBCXX_RESOLVE_LIB_DEFECTS > > // DR 130. Associative erase should return an iterator. > > @@ -2518,6 +2521,20 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION > > return __old_size - size(); > > } > > > > + template > + typename _Compare, typename _Alloc> > > + typename _Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>::size= _type > > + _Rb_tree<_Key, _Val, _KeyOfValue, _Compare, _Alloc>:: > > + _M_erase_unique(const _Key& __x) > > + { > > + iterator __it =3D find(__x); > > + if (__it =3D=3D end()) > > + return 0; > > + > > + _M_erase_aux(__it); > > + return 1; > > + } > > + > > template > typename _Compare, typename _Alloc> > > typename _Rb_tree<_Key, _Val, _KeyOfValue, > > -- > > 2.44.0 > > > > >