Re: [PATCH 2/7] PowerPC: add unlikely() to BUG_ON()

From: Andreas Schwab
Date: Fri Jan 28 2011 - 05:14:49 EST


"David Laight" <David.Laight@xxxxxxxxxx> writes:

> Also, as (I think) in some of the generated code quoted,
> use of __builtin_expect() with a boolean expression can
> force some versions of gcc to generate the integer
> value of the expression

That's more likely a side effect of the definition of likely/unlikely:
they expand to !!(x).

Andreas.

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