Path: utzoo!attcan!uunet!ncrlnk!ncrcae!hubcap!gatech!uflorida!haven!uvaarpa!babbage!mac3n
From: mac3n@babbage.acc.virginia.edu (Alex Colvin)
Newsgroups: comp.arch
Subject: Re: RISC v. CISC --more misconceptions
Summary: Gray to Binary
Message-ID: <398@babbage.acc.virginia.edu>
Date: 8 Nov 88 18:59:20 GMT
References: <156@gloom.UUCP> <18931@apple.Apple.COM> <40@sopwith.UUCP> <475@oracle.UUCP>
Organization: University of Virginia
Lines: 14

In article <475@oracle.UUCP>, csimmons@hqpyr1.oracle.UUCP (Charles Simmons) writes:
> In article <998@l.cc.purdue.edu> cik@l.cc.purdue.edu (Herman Rubin) writes:
> >     Find the distance to the next one in a bit stream FAST.

> ended up using a floating point normalize, which was still fairly slow).

In 1972 in "Structured Programming", C.A.R.  Hoare suggests using
(floating) standardisation to locate elements in a powerset representation.
This operation seems to have been lost in Pascal.

Charles Simmons may remember the GE635's GTB (Gray to Binary) instruction,
which executes a long chain of XORs, used to convert radar data to binary.
We had real trouble coming up with another use for this.  Maybe Hypercube
routing?