Messages in this thread |  | | Subject | Re: Linux 2.4.10-pre11 -- __builtin_expect | From | James Antill <> | Date | 27 Sep 2001 11:41:22 -0400 |
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Andreas Schwab <schwab@suse.de> writes:
> James Antill <james@and.org> writes: > > |> unlikely() also needs to be... > |> > |> #define unlikely(x) __builtin_expect(!(x), 1) > |> > |> ...or... > |> > |> #define unlikely(x) __builtin_expect(!!(x), 0) > > This is not needed, since only 0 is the likely value and !! does not > change that.
Yes it is, given the code...
struct blah *ptr = NULL;
if (unlikely(ptr))
...you'll get a warning from gcc because you are implicitly converting from a pointer to a long.
-- # James Antill -- james@and.org :0: * ^From: .*james@and\.org /dev/null - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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