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From: Willem <willem@toad.stack.nl>
Newsgroups: comp.lang.c
Subject: Re: Short-circuiting in C
Date: Fri, 27 May 2011 16:08:07 +0000 (UTC)
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ImpalerCore wrote:
) On May 26, 1:58?pm, Billy Mays <no...@nohow.com> wrote:
)> I was wondering if there is a way to avoid the C short circuiting for
)> boolean expressions such as the following:
)>
)> if(a && b && c) {
)> ? ? ?/* Do stuff */
)>
)> }
)>
)> I am currently doing GPU programming and it would be better to evaluate
)> the entire condition, even if a is 0, since branches are slow.
)
) Not sure if it would work, but what about evaluating the condition
) outside of the 'if' statement?
)
) bool my_condition_is_true = a && b && c;
) if (my_condition_is_true) {
)   /* Do stuff */
) }

Nope, that would make the exact same branches.
I wouldn't be surprised if it generated exactly the same opcodes, even.


SaSW, Willem
-- 
Disclaimer: I am in no way responsible for any of the statements
            made in the above text. For all I know I might be
            drugged or something..
            No I'm not paranoid. You all think I'm paranoid, don't you !
#EOT