Re: Bit Swizzling

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From	"John Levine" <johnl@taugh.com>
Newsgroups	comp.arch, comp.compilers
Subject	Re: Bit Swizzling
Date	5 Sep 2020 18:50:16 -0000
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Cross-posted to 2 groups.

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In article <rivvah$1neg$2@gioia.aioe.org>,
>> -----
>> 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

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Bit Swizzling "Rick C. Hodgin" <rick.c.hodgin@nospicedham.gmail.com> - 2020-09-04 20:33 -0400
  Re: Bit Swizzling MitchAlsup <MitchAlsup@aol.com> - 2020-09-04 18:26 -0700
    Re: Bit Swizzling MitchAlsup <MitchAlsup@aol.com> - 2020-09-04 18:27 -0700
  Re: Bit Swizzling Joshua Landau <joshua.landau.ws@gmail.com> - 2020-09-04 20:32 -0700
    Re: Bit Swizzling "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2020-09-05 09:16 -0400
  Re: Bit Swizzling Bart <bc@nospicedham.freeuk.com> - 2020-09-05 12:33 +0100
  Re: Bit Swizzling Chris <xxx.syseng.yyy@gfsys.co.uk> - 2020-09-05 13:12 +0100
    Re: Bit Swizzling "John Levine" <johnl@taugh.com> - 2020-09-05 18:50 +0000
      Re: Bit Swizzling "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2020-09-06 11:01 -0400
      Re: Bit Swizzling Chris <xxx.syseng.yyy@gfsys.co.uk> - 2020-09-06 17:48 +0100
  Re: Bit Swizzling olcott <NoOne@nospicedham.NoWhere.com> - 2020-09-08 11:25 -0500
    Re: Bit Swizzling olcott <NoOne@nospicedham.NoWhere.com> - 2020-09-08 11:50 -0500

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