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[QUOTE="Keith Thompson, post: 4214685"]
You do?  The point was to avoid differing branches depending on
differing values of a, b, and c.  In the if() form, the branches are,
in some sense, even more explicit than in the && form.

The problem is that the C language defines *behavior*, and you're trying
to control the manner in which that behavior is created, i.e., the
sequence of machine-level operations.  There's no 100% reliable way to
do that.

Of course you're going to have *some* inconsistent branching; depending
on the values of a, b, and c, each thread will or will not execute the
body of the if statement.  So you're trying to minimize the possible
differences in branching.

I think your best bet is probably to try a few possible solutions and
examine the generated assembly or machine language for each one.  If the
compiler knows that branching is expensive, it might optimize
if (a && b && c)
into straight-line code.  That's assuming b and c have no side effects,
which you can guarantee by storing their values in temporary variables.
[/QUOTE]

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