From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.org/gmane.linux.lib.musl.general/11338 Path: news.gmane.org!.POSTED!not-for-mail From: Rich Felker Newsgroups: gmane.linux.lib.musl.general Subject: Re: Musl libm optimizations for Power and Z Date: Wed, 17 May 2017 12:33:42 -0400 Message-ID: <20170517163342.GI17319@brightrain.aerifal.cx> References: <20170517142616.GG9350@port70.net> Reply-To: musl@lists.openwall.com NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: blaine.gmane.org 1495038835 13084 195.159.176.226 (17 May 2017 16:33:55 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Wed, 17 May 2017 16:33:55 +0000 (UTC) User-Agent: Mutt/1.5.21 (2010-09-15) To: musl@lists.openwall.com Original-X-From: musl-return-11353-gllmg-musl=m.gmane.org@lists.openwall.com Wed May 17 18:33:51 2017 Return-path: Envelope-to: gllmg-musl@m.gmane.org Original-Received: from mother.openwall.net ([195.42.179.200]) by blaine.gmane.org with smtp (Exim 4.84_2) (envelope-from ) id 1dB1tW-0003Ik-RN for gllmg-musl@m.gmane.org; Wed, 17 May 2017 18:33:50 +0200 Original-Received: (qmail 17413 invoked by uid 550); 17 May 2017 16:33:54 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Original-Received: (qmail 16371 invoked from network); 17 May 2017 16:33:54 -0000 Content-Disposition: inline In-Reply-To: Original-Sender: Rich Felker Xref: news.gmane.org gmane.linux.lib.musl.general:11338 Archived-At: On Wed, May 17, 2017 at 10:52:05AM -0400, David Edelsohn wrote: > On Wed, May 17, 2017 at 10:26 AM, Szabolcs Nagy wrote: > > * David Edelsohn [2017-05-17 09:49:22 -0400]: > >> Are there any musl developers who would be interested to work on musl > >> libm optimizations for Power and Z as financial bounties? > > > > i hope it is something upstreamable > > (i'm interested in libm optimizations, but cant work for bounties) > > I'm not certain what you mean. We want musl libm to include > optimizations for Power and Z in the musl repository and releases. Upstreamability could include 2 things: both your/contributor's willingness to submit the code upstream, and appropriateness of it for inclusion. In general we avoid having per-arch math code that's more than simple fpu instruction wrappers -- math/i386/*.s is about the upper bound on what I have in mind, as opposed to something like using an entirely different C algorithm that just happens to be faster on the arch or that only tangentially uses arch-specific insns. And more importantly, arch-specific math asm should not be sacrificing correctness/quality of results for performance or other considerations. We're also aiming to use inline asm in C files, rather than .s/.S source files, for new math asm. This allows inlining with LTO, avoids putting as many calling convention/ABI assumptions in the asm, and makes it easier to switch off conditionally for soft-float builds (see src/math/arm/*.c for examples). Rich