From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-il1-x129.google.com (mail-il1-x129.google.com [IPv6:2607:f8b0:4864:20::129]) by sourceware.org (Postfix) with ESMTPS id A0C4B385F033 for ; Fri, 6 Aug 2021 07:53:00 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org A0C4B385F033 Received: by mail-il1-x129.google.com with SMTP id i9so7927717ilk.9 for ; Fri, 06 Aug 2021 00:53:00 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=rwMLkzNe6aF8LrKdh9OsuMmNBrrzkdhe3QaL0xImwvU=; b=fut/gp1cxiOg1euPMxRb/G3VTJdFCnq1wXUr7CNZxvNw/EvmfryT1JYd+yngU31oMk JPShnbexHNW76F1yvy3zXMrXw7ZYu3cIe2WZ7CDcNN7J41GWVs+6/0uvfAG/1+mJksGk QqKS2v7DbOXbfX5eCQjiSe6Dpu1woEJ4tna+9G95gL6eMpQ3azLlI7wWrI8rnUv+0qBM 8Ll8HIPzYcSy71I5ajzCqJV0lVY2aAueeUmW5tYxotBRwigufsQdeo8Y29oWZVZhUZuO gcNQ4PDL7G6hhQ5vHcp6Yv2TSDEaN1EfT5J64aSIy1Jal9FneoCZE1Q2VcziyCT5zJwe NqbA== X-Gm-Message-State: AOAM5329QGXwgAQyyDe+fTS8p42FspGJNHPMZYyza27jB/D+2xgbSR+8 PQk403i+kCvL4H95U9bh1d1TGQPzirliy3IwfbA= X-Google-Smtp-Source: ABdhPJw5LsPN7P+6MUCNvyJkK5+RugzikfH3chRMMBPrIy0v+YkQtyIADdH/Nif7c7OHd+uQDsFVDzQT/+Qz1Cyt/nQ= X-Received: by 2002:a05:6e02:1543:: with SMTP id j3mr769678ilu.308.1628236380128; Fri, 06 Aug 2021 00:53:00 -0700 (PDT) MIME-Version: 1.0 References: <390c6652-0a1f-e8c4-d70d-56ced2f7b0fb@gmail.com> <0ee2488c-04a1-df3b-dd4f-92eec51a4ab2@redhat.com> <7ebb37f3-76c3-8e00-7852-c93bf142043a@gmail.com> <2c60a7d0-3f60-b72f-c0f2-6fc7a4900740@redhat.com> <072a4715-2248-d836-948d-50426160de47@gmail.com> <6ed67ff9-12d3-516a-f7ec-13dd913ed54b@gmail.com> <0bdbdf77-e887-f15a-4b32-0eee6bcf30a9@gmail.com> <3c6631e9-d95c-dbf6-e50e-cee99f8652d7@redhat.com> In-Reply-To: From: Christophe Lyon Date: Fri, 6 Aug 2021 09:52:48 +0200 Message-ID: Subject: Re: [PING][PATCH] define auto_vec copy ctor and assignment (PR 90904) To: Martin Sebor Cc: Jason Merrill , Jonathan Wakely , Richard Biener , gcc-patches X-Spam-Status: No, score=-2.9 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, FREEMAIL_FROM, HTML_MESSAGE, KAM_SHORT, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.29 X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 06 Aug 2021 07:53:03 -0000 On Fri, Aug 6, 2021 at 4:07 AM Martin Sebor via Gcc-patches < gcc-patches@gcc.gnu.org> wrote: > On 7/30/21 9:06 AM, Jason Merrill wrote: > > On 7/27/21 2:56 PM, Martin Sebor wrote: > >> Ping: https://gcc.gnu.org/pipermail/gcc-patches/2021-July/575690.html > >> > >> Are there any other suggestions or comments or is the latest revision > >> okay to commit? > > > > OK. > > I had to make a few more adjustments to fix up code that's snuck > in since I last tested the patch. I committed r12-2776 after > retesting on x86_64-linux. > > With the cleanup out of the way I'll resubmit the copy ctor patch > next. > > Hi Martin, Your patch breaks the aarch64 build: /tmp/1784440_6.tmpdir/aci-gcc-fsf/sources/gcc-fsf/gccsrc/gcc/config/aarch64/aarch64-sve-builtins.cc: In function 'void aarch64_sve::register_svpattern()': /tmp/1784440_6.tmpdir/aci-gcc-fsf/sources/gcc-fsf/gccsrc/gcc/config/aarch64/aarch64-sve-builtins.cc:3502:27: error: use of deleted function 'vec::vec(auto_vec&) [with long unsigned int N = 32ul; T = std::pair]' "svpattern", values); ^ In file included from /tmp/1784440_6.tmpdir/aci-gcc-fsf/sources/gcc-fsf/gccsrc/gcc/hash-table.h:248:0, from /tmp/1784440_6.tmpdir/aci-gcc-fsf/sources/gcc-fsf/gccsrc/gcc/coretypes.h:480, from /tmp/1784440_6.tmpdir/aci-gcc-fsf/sources/gcc-fsf/gccsrc/gcc/config/aarch64/aarch64-sve-builtins.cc:24: /tmp/1784440_6.tmpdir/aci-gcc-fsf/sources/gcc-fsf/gccsrc/gcc/vec.h:1455:3: error: declared here vec (auto_vec &) = delete; ^ /tmp/1784440_6.tmpdir/aci-gcc-fsf/sources/gcc-fsf/gccsrc/gcc/config/aarch64/aarch64-sve-builtins.cc: In function 'void aarch64_sve::register_svprfop()': /tmp/1784440_6.tmpdir/aci-gcc-fsf/sources/gcc-fsf/gccsrc/gcc/config/aarch64/aarch64-sve-builtins.cc:3516:30: error: use of deleted function 'vec::vec(auto_vec&) [with long unsigned int N = 16ul; T = std::pair]' "svprfop", values); ^ In file included from /tmp/1784440_6.tmpdir/aci-gcc-fsf/sources/gcc-fsf/gccsrc/gcc/hash-table.h:248:0, from /tmp/1784440_6.tmpdir/aci-gcc-fsf/sources/gcc-fsf/gccsrc/gcc/coretypes.h:480, from /tmp/1784440_6.tmpdir/aci-gcc-fsf/sources/gcc-fsf/gccsrc/gcc/config/aarch64/aarch64-sve-builtins.cc:24: /tmp/1784440_6.tmpdir/aci-gcc-fsf/sources/gcc-fsf/gccsrc/gcc/vec.h:1455:3: error: declared here vec (auto_vec &) = delete; ^ Can you check? Thanks, Christophe > > Martin > > > > >> On 7/20/21 12:34 PM, Martin Sebor wrote: > >>> On 7/14/21 10:23 AM, Jason Merrill wrote: > >>>> On 7/14/21 10:46 AM, Martin Sebor wrote: > >>>>> On 7/13/21 9:39 PM, Jason Merrill wrote: > >>>>>> On 7/13/21 4:02 PM, Martin Sebor wrote: > >>>>>>> On 7/13/21 12:37 PM, Jason Merrill wrote: > >>>>>>>> On 7/13/21 10:08 AM, Jonathan Wakely wrote: > >>>>>>>>> On Mon, 12 Jul 2021 at 12:02, Richard Biener wrote: > >>>>>>>>>> Somebody with more C++ knowledge than me needs to approve the > >>>>>>>>>> vec.h changes - I don't feel competent to assess all effects > >>>>>>>>>> of the change. > >>>>>>>>> > >>>>>>>>> They look OK to me except for: > >>>>>>>>> > >>>>>>>>> -extern vnull vNULL; > >>>>>>>>> +static constexpr vnull vNULL{ }; > >>>>>>>>> > >>>>>>>>> Making vNULL have static linkage can make it an ODR violation > >>>>>>>>> to use > >>>>>>>>> vNULL in templates and inline functions, because different > >>>>>>>>> instantiations will refer to a different "vNULL" in each > >>>>>>>>> translation > >>>>>>>>> unit. > >>>>>>>> > >>>>>>>> The ODR says this is OK because it's a literal constant with the > >>>>>>>> same value (6.2/12.2.1). > >>>>>>>> > >>>>>>>> But it would be better without the explicit 'static'; then in > >>>>>>>> C++17 it's implicitly inline instead of static. > >>>>>>> > >>>>>>> I'll remove the static. > >>>>>>> > >>>>>>>> > >>>>>>>> But then, do we really want to keep vNULL at all? It's a weird > >>>>>>>> blurring of the object/pointer boundary that is also dependent > >>>>>>>> on vec being a thin wrapper around a pointer. In almost all > >>>>>>>> cases it can be replaced with {}; one exception is == > >>>>>>>> comparison, where it seems to be testing that the embedded > >>>>>>>> pointer is null, which is a weird thing to want to test. > >>>>>>> > >>>>>>> The one use case I know of for vNULL where I can't think of > >>>>>>> an equally good substitute is in passing a vec as an argument by > >>>>>>> value. The only way to do that that I can think of is to name > >>>>>>> the full vec type (i.e., the specialization) which is more typing > >>>>>>> and less generic than vNULL. I don't use vNULL myself so I > wouldn't > >>>>>>> miss this trick if it were to be removed but others might feel > >>>>>>> differently. > >>>>>> > >>>>>> In C++11, it can be replaced by {} in that context as well. > >>>>> > >>>>> Cool. I thought I'd tried { } here but I guess not. > >>>>> > >>>>>> > >>>>>>> If not, I'm all for getting rid of vNULL but with over 350 uses > >>>>>>> of it left, unless there's some clever trick to make the removal > >>>>>>> (mostly) effortless and seamless, I'd much rather do it > >>>>>>> independently > >>>>>>> of this initial change. I also don't know if I can commit to making > >>>>>>> all this cleanup. > >>>>>> > >>>>>> I already have a patch to replace all but one use of vNULL, but > >>>>>> I'll hold off with it until after your patch. > >>>>> > >>>>> So what's the next step? The patch only removes a few uses of vNULL > >>>>> but doesn't add any. Is it good to go as is (without the static and > >>>>> with the additional const changes Richard suggested)? This patch is > >>>>> attached to my reply to Richard: > >>>>> https://gcc.gnu.org/pipermail/gcc-patches/2021-July/575199.html > >>>> > >>>> As Richard wrote: > >>>> > >>>>> The pieces where you change vec<> passing to const vec<>& and the few > >>>>> where you change vec<> * to const vec<> * are OK - this should make > >>>>> the > >>>>> rest a smaller piece to review. > >>>> > >>>> Please go ahead and apply those changes and send a new patch with > >>>> the remainder of the changes. > >>> > >>> I have just pushed r12-2418: > >>> https://gcc.gnu.org/pipermail/gcc-cvs/2021-July/350886.html > >>> > >>>> > >>>> A few other comments: > >>>> > >>>>> - omp_declare_simd_clauses); > >>>>> + *omp_declare_simd_clauses); > >>>> > >>>> Instead of doing this indirection in all of the callers, let's > >>>> change c_finish_omp_declare_simd to take a pointer as well, and do > >>>> the indirection in initializing a reference variable at the top of > >>>> the function. > >>> > >>> Okay. > >>> > >>>> > >>>>> + sched_init_luids (bbs.to_vec ()); > >>>>> + haifa_init_h_i_d (bbs.to_vec ()); > >>>> > >>>> Why are these to_vec changes needed when you are also changing the > >>>> functions to take const&? > >>> > >>> Calling to_vec() here isn't necessary so I've removed it. > >>> > >>>> > >>>>> - vec checks = LOOP_VINFO_CHECK_NONZERO (loop_vinfo); > >>>>> + vec checks = LOOP_VINFO_CHECK_NONZERO (loop_vinfo).to_vec > (); > >>>> > >>>> Why not use a reference here and in other similar spots? > >>> > >>> Sure, that works too. > >>> > >>> Attached is what's left of the original changes now that r12-2418 > >>> has been applied. > >>> > >>> Martin > >> > > > >