From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-3.3 required=5.0 tests=MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED,RCVD_IN_MSPIKE_H3,RCVD_IN_MSPIKE_WL autolearn=ham autolearn_force=no version=3.4.4 Received: (qmail 19764 invoked from network); 7 Sep 2020 18:09:17 -0000 Received: from mother.openwall.net (195.42.179.200) by inbox.vuxu.org with ESMTPUTF8; 7 Sep 2020 18:09:17 -0000 Received: (qmail 27675 invoked by uid 550); 7 Sep 2020 18:09:15 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Reply-To: musl@lists.openwall.com Received: (qmail 27654 invoked from network); 7 Sep 2020 18:09:14 -0000 Date: Mon, 7 Sep 2020 14:09:02 -0400 From: Rich Felker To: musl@lists.openwall.com Message-ID: <20200907180902.GN3265@brightrain.aerifal.cx> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Subject: Re: [musl] riscv32 v2 On Mon, Sep 07, 2020 at 07:27:37AM -0400, Stefan O'Rear wrote: > On Fri, Sep 4, 2020, at 1:48 AM, Stefan O'Rear wrote: > > Rich Felker's suggestion (on IRC) to use a 0-instruction __get_tp was > > NOT implemented after discovering that it generates dramatically worse > > code on clang and cannot easily be conditionalized. Bug reports to come. > > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96952 > https://bugs.llvm.org/show_bug.cgi?id=47447 Thanks! I think the GCC issue & response to it supports my preference not to use GCC __builtin_*, but I would like to see them fix it. The form with __asm__("" : ...) is semantically correct and has always worked, but I don't see enough benefit over the current non-empty asm to justify accepting the worse codegen from llvm getting it wrong. Maybe we can change it at some point in the future after llvm is fixed, but it's really no big deal. Rich