From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=unavailable autolearn_force=no version=3.4.4 X-Received: by 2002:a05:620a:131b:: with SMTP id o27mr373857qkj.423.1570044315079; Wed, 02 Oct 2019 12:25:15 -0700 (PDT) X-Received: by 2002:aca:ec06:: with SMTP id k6mr4032205oih.78.1570044314784; Wed, 02 Oct 2019 12:25:14 -0700 (PDT) Path: eternal-september.org!reader01.eternal-september.org!feeder.eternal-september.org!news.dns-netz.com!news.freedyn.net!newsreader4.netcologne.de!news.netcologne.de!peer01.ams1!peer.ams1.xlned.com!news.xlned.com!peer01.am4!peer.am4.highwinds-media.com!peer01.iad!feed-me.highwinds-media.com!news.highwinds-media.com!o24no7674qtl.0!news-out.google.com!x7ni570qtf.0!nntp.google.com!o24no7672qtl.0!postnews.google.com!glegroupsg2000goo.googlegroups.com!not-for-mail Newsgroups: comp.lang.ada Date: Wed, 2 Oct 2019 12:25:14 -0700 (PDT) In-Reply-To: Complaints-To: groups-abuse@google.com Injection-Info: glegroupsg2000goo.googlegroups.com; posting-host=47.185.223.245; posting-account=zwxLlwoAAAChLBU7oraRzNDnqQYkYbpo NNTP-Posting-Host: 47.185.223.245 References: <869af4e9-08df-486d-8c87-9040c39a151f@googlegroups.com> <0407f247-46a2-4649-8974-c11d539c399e@googlegroups.com> <55a93d93-67a5-4cdb-a7e0-4c8117dc1278@googlegroups.com> <3facd621-48a1-4ffa-8af4-c1893dcebb42@googlegroups.com> User-Agent: G2/1.0 MIME-Version: 1.0 Message-ID: <547965ff-1dc4-4102-aa03-4abb93d523b9@googlegroups.com> Subject: Re: Well, they kept that quiet! From: Optikos Injection-Date: Wed, 02 Oct 2019 19:25:15 +0000 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Received-Bytes: 4392 X-Received-Body-CRC: 2176001376 Xref: reader01.eternal-september.org comp.lang.ada:57233 Date: 2019-10-02T12:25:14-07:00 List-Id: On Wednesday, October 2, 2019 at 11:37:23 AM UTC-5, Simon Wright wrote: > Optikos writes: >=20 > > which is then passed =E2=80=A2IN MEMORY WITHIN THE SAME PROCESS=E2=80= =A2 onto the LLVM > > tools as/ld/polly =E2=80=A2THAT ARE LINKED INTO THE COMPILER AS THE SAM= E > > PROCESS AS THE COMPILER=E2=80=A2 >=20 > No idea what polly is Polly is the quite admirable polyhedral optimizer phases, and is the most-f= amous archetype representative of other IR-to-IR transforms in the LLVM eco= system. The LLVM ecosystem is well-known for having many more (and more so= phisticated) IR-processing/reprocessing stages via plug-ins immediately ahe= ad of the final as & ld step than GCC has or is capable of. Because of the= failure of GCC-XML vis a vis the contract-law IR complications of Eligible= Compilation Process in GPLv3 RLE, GCC-world has had drastically fewer of t= hese IR-to-IR value-added transforms. > but you are wrong about as & ld Obviously I am not talking about bland mundane =E2=80=A2=E2=80=A2unoptimize= d na=C3=AFve=E2=80=A2=E2=80=A2 Target Code being fed into as and ld with al= l value-adds turned off or inhibited in LLVM. I am clearly referring to al= l the commonly-utilized actually-extant value-adds in the LLVM ecosystem th= at produce any kind of optimization or correctness-improving rewrite or any= other value-add transform of the IR or of the IR-to-Target-Code generated = that is then fed into as and ld, where as and ld are none the wiser that a = prior stage improved the IR or the Target Code by rewriting it a little or = a lot when compared to its bland/unoptimized/na=C3=AFve/mundane starting po= int at an even earlier phase. Your criticism is focusing (ridiculously) on= the none-the-wiser part there at the input orifice of as and ld; I am focu= sing on the rewriting-it part there in that prior sentence immediately prio= r to feeding it into that orifice. It is the rewriting-it part commonplace= in the LLVM ecosystem that can very easily run afoul of the Eligible Compi= lation Process criteria in the RLE of GPLv3 (unless one assures a single co= mpilation process without IPCing IR and without file-writing of IR or unles= s one is fine with strict GPLv3-without-RLE licensing for the generated obj= ect code and executable or DLL). Because the phasing of LLVM-world's IR-transformation ecosystem is more com= plex than GCC's, the thinking and critical analysis also needs to be equall= y more complex to still meet the criteria of Eligible Compilation Process i= n GPLv3's RLE for linking to the FSF-sourced standard library. Ignoring th= e =E2=80=A2=E2=80=A2intersection=E2=80=A2=E2=80=A2 of 1) the technical deta= ils with 2) the contract-law details is not really an option (unless one ac= tually wants strict GPLv3-without-RLE licensing for the generated object co= de and executable or DLL).