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Likely unlikely()s

Likely unlikely()s

Posted Dec 16, 2010 4:53 UTC (Thu) by JoeBuck (subscriber, #2330)
Parent article: Likely unlikely()s

I recall that there was once a compiler that implemented the user-specified branch likelihood hint backwards and it was at least a year before anyone noticed, but this may be an apocryphal story. Does anyone remember?


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Likely unlikely()s

Posted Dec 16, 2010 14:45 UTC (Thu) by Yorick (subscriber, #19241) [Link]

I have heard that story been told in conjunction with the FORTRAN's original FREQUENCY statement, which allegely was dropped because of this (and because humans turned out to be bad at estimating branch frequencies in general). Anyway, I cannot seem to find a source for this either.

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