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=ham autolearn_force=no version=3.4.4 X-Google-Thread: 103376,9dec3ff1604723d9 X-Google-Attributes: gid103376,public X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news1.google.com!news2.google.com!news.maxwell.syr.edu!border1.nntp.dca.giganews.com!border2.nntp.dca.giganews.com!nntp.giganews.com!cyclone1.gnilink.net!spamkiller2.gnilink.net!gnilink.net!trndny07.POSTED!c2bfcbcf!not-for-mail Newsgroups: comp.lang.ada Subject: Re: Bitmanipulation in Ada References: <87k6vwrwym.fsf@insalien.org> Message-ID: From: "Ed Falis" Content-Type: text/plain; format=flowed; delsp=yes; charset=us-ascii MIME-Version: 1.0 Content-Transfer-Encoding: 8bit User-Agent: Opera M2/7.54 (Linux, build 751) Date: Wed, 18 Aug 2004 21:18:06 GMT NNTP-Posting-Host: 141.154.17.233 X-Complaints-To: abuse@verizon.net X-Trace: trndny07 1092863886 141.154.17.233 (Wed, 18 Aug 2004 17:18:06 EDT) NNTP-Posting-Date: Wed, 18 Aug 2004 17:18:06 EDT Xref: g2news1.google.com comp.lang.ada:2818 Date: 2004-08-18T21:18:06+00:00 List-Id: On 18 Aug 2004 21:10:30 GMT, Bernd Specht wrote: > Ok. Is there a reason why it is not (directly) available in the language > itself like the and/or/xor or the >> and << in C? Doesn't really matter, since most implementations directly generate the code for these (they treat them as "instrinsic"). > > OK, but this would result in an assignment operation (a memory move on > maschine code level). What I want is a real "overlay" (same storage > location > used for both), so reading the value would not need extra instructions. In all implementations of which I'm aware (and I've been in the Ada compiler business for over 20 years) no code would be generated for an unchecked conversion where the source and target have the same size. You sound like you're looking for things to complain about, by the way. - Ed -- "When I was a kid, I wanted to grow up to be a wise man. Somehow, I just turned out to be a wise guy".