Path: csiph.com!xmission!news.snarked.org!border2.nntp.dca1.giganews.com!nntp.giganews.com!news.iecc.com!.POSTED.news.iecc.com!nerds-end From: "John Levine" Newsgroups: comp.arch,comp.compilers Subject: Re: Bit Swizzling Date: 5 Sep 2020 18:50:16 -0000 Organization: Taughannock Networks Lines: 16 Sender: news@iecc.com Approved: comp.compilers@iecc.com Message-ID: <20-09-016@comp.compilers> References: <20-09-014@comp.compilers> Injection-Info: gal.iecc.com; posting-host="news.iecc.com:2001:470:1f07:1126:0:676f:7373:6970"; logging-data="1888"; mail-complaints-to="abuse@iecc.com" Keywords: optimize Posted-Date: 05 Sep 2020 14:52:13 EDT X-submission-address: compilers@iecc.com X-moderator-address: compilers-request@iecc.com X-FAQ-and-archives: http://compilers.iecc.com Cleverness: some Xref: csiph.com comp.arch:61312 comp.compilers:2587 In article , >> ----- >> Are there any algorithms which take a known-at-compile-time sequence >> of bitwise operations on an 8-bit to 64-bit quantity, and optimize >> them down to their minimal set of operations? >Why not just use a lookup table ?. Minimum ops and fast... Assuming you're looking for something you can implement in logic rather than by table lookup, it sounds like a set of Karnaugh maps. -- Regards, John Levine, johnl@taugh.com, Primary Perpetrator of "The Internet for Dummies", Please consider the environment before reading this e-mail. https://jl.ly