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From: grover@brahmand.Eng.Sun.COM (Vinod Grover)
Newsgroups: comp.lang.misc
Subject: Re: C vs. FORTRAN (was C official DOD langauge?)
Message-ID: <136827@sun.Eng.Sun.COM>
Date: 7 Jun 90 17:45:39 GMT
References: <1633@dinl.mmc.UUCP> <3169@goanna.cs.rmit.oz.au>
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In article <3169@goanna.cs.rmit.oz.au> ok@goanna.cs.rmit.oz.au (Richard A. O'Keefe) writes:
>:       b.  The C for statement does not have a well defined
>:           "control variable" and thus cannot be automatically
>:           vectorized.
>
>Bogus.  It is true that there is no _syntactically_ distinguished
>variable, but all you have to do is watch out for a variable which
>is incremented by a constant and is tested against an invariant bound.

Also, make sure that the variable is not subject to hidden side-effects, if
you want to vectorize the loop or perform strength reductions on operations
involving that variable.