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From: doug@cs.dartmouth.edu (Doug McIlroy)
Subject: [TUHS] arithmetic IF (was origin of string.h and ctype.h)
Date: Thu, 17 Aug 2017 09:38:56 -0400	[thread overview]
Message-ID: <201708171338.v7HDcu2s006401@coolidge.cs.Dartmouth.EDU> (raw)

> According to the Wikipedia article on FORTRAN, CAS was usually not the
> most efficient way to implement arithmetic IF anyway.  CAS takes up
> four words of memory and takes three cycles to execute, whereas you
> can do it in two words and two cycles with the transfer instructions.

Though the article's conclusion was right, its numbers were wrong. 
As a correct discussion of possible implementations of arithmetic-IF
would be long and essentially off topic, I have chopped most of it
out of the article.

doug


             reply	other threads:[~2017-08-17 13:38 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-08-17 13:38 Doug McIlroy [this message]
     [not found] <mailman.921.1502995544.3779.tuhs@minnie.tuhs.org>
2017-08-17 22:19 ` Paul McJones
2017-08-18 10:49   ` arnold
  -- strict thread matches above, loose matches on Subject: below --
2017-08-17 15:14 Doug McIlroy
2017-08-16 18:04 Paul Winalski
2017-08-16 23:54 ` Greg 'groggy' Lehey
2017-08-17 14:04   ` arnold

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