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Date: Thu, 8 Feb 2007 23:24:44 +0100
From: Jens Schweikhardt <schweikh@schweikhardt.net>
To: Luigi Rizzo <rizzo@icir.org>
Message-ID: <20070208222444.GA2994@schweikhardt.net>
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Cc: current@freebsd.org
Subject: Re: C macro to find the next power of 2 ?
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Luigi,

...
# 
# But i was wondering if there is some simpler code which
# can still be computed as a compile-time constant?

Is this requirement non-negotiable? Maybe in the days of C99
and run-time sized arrays it's worth thinking about other solutions
than CPP magic.

For this and other bit twiddling hacks in C (mostly functional), see
http://graphics.stanford.edu/~seander/bithacks.html#RoundUpPowerOf2

Regards,

	Jens
-- 
Jens Schweikhardt http://www.schweikhardt.net/
SIGSIG -- signature too long (core dumped)