Date: Thu, 24 Jun 2004 02:31:09 -0700
From: Paul Jackson <pj@sgi.com>
To: Arjan van de Ven <arjanv@redhat.com>
Cc: linux-kernel@vger.kernel.org, torvalds@osdl.org, akpm@osdl.org
Subject: Re: using gcc built-ins for bitops?
Message-Id: <20040624023109.6213c1ce.pj@sgi.com>
In-Reply-To: <20040624070936.GB30057@devserv.devel.redhat.com>
References: <20040624070936.GB30057@devserv.devel.redhat.com>
Organization: SGI
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I see a list of these gcc bitop builtins at the bottom of the page:

  http://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html

Looks like you can find the position of the first 1 bit, the length of
the leading or trailing seq of 0 bits, the hamming weight (popcount) and
the parity, each for int, long and long long.

I just add this for the benefit of others.

As to your primary question - is this worth doing - I don't have
an answer.

-- 
                          I won't rest till it's the best ...
                          Programmer, Linux Scalability
                          Paul Jackson <pj@sgi.com> 1.650.933.1373
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