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 Path: eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!news.eternal-september.org!news.eternal-september.org!feeder.eternal-september.org!news.swapon.de!fu-berlin.de!uni-berlin.de!individual.net!not-for-mail From: Niklas Holsti Newsgroups: comp.lang.ada Subject: Re: Ada 2012 Constraints (WRT an Ada IR) Date: Tue, 13 Dec 2016 22:45:54 +0200 Organization: Tidorum Ltd Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit X-Trace: individual.net a3OfwJ9QO5MUHqKcEyFsKgtUvHC12e1+LuFSq2r9Xys+5R3bcQ Cancel-Lock: sha1:fLZBRWCIlIQ+HIn50Q+kjXxJyJU= User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:45.0) Gecko/20100101 Thunderbird/45.5.1 In-Reply-To: Xref: news.eternal-september.org comp.lang.ada:32784 Date: 2016-12-13T22:45:54+02:00 List-Id: On 16-12-13 02:41 , Randy Brukardt wrote: > "Niklas Holsti" wrote in message > news:eb0po8Fgob2U1@mid.individual.net... >> On 16-12-09 23:41 , Randy Brukardt wrote: > ... >>> Trying to put a predicate logic prover into a compiler optimizer sounds >>> challenging at best. >> >> I'm a little surprised: I seem to remember that you have, earlier, said >> that you would like future compilers to prove all sorts of things about >> the program. But you were not thinking of predicate logic proofs? > > Potentially different parts of the compiler. And, no, I wasn't thinking of > predicate logic proofs so much as simple common subexpression elimination, > algebraic reductions, flow analysis, and other existing, common optimization > techniques. I see -- something like what CodePeer does, but integrated with the compiler. > The problem with these is more in usefully reporting the results > to the user than with actually doing them (as they likely already exist in > compilers, but tend to be used on lower-level code formats). In particular, > one would want to report to the user when a precondition or postcondition > cannot be optimized to "True", but how to do that usefully (in the back-end > of a compiler where little source information remains), and especially > avoiding too much nattering, isn't obvious to me. > > Randy. Yes. Also the output from CodePeer can be rather voluminous and hard to understand, or so I have been told by my colleagues who are actively using it. I aim to start using it, as soon as other tasks permit :-) -- Niklas Holsti Tidorum Ltd niklas holsti tidorum fi . @ .