Re: [PATCH] 2.4.22pre10: {,un}likely_p() macros for pointers

From: Jamie Lokier
Date: Mon Aug 11 2003 - 00:44:32 EST


Willy Tarreau wrote:
> It may well be when you use it in boolean constructs. The following functions
> return exactly the same result with different code :
>
> int test1(int u, int v, int x, int y) {
> return (u > v) || (x > y);
> }
>
> int test2(int u, int v, int x, int y) {
> return !!(u > v) | !!(x > y);
> }

Yes, it sounds familiar. Although my code was not as contrived :) it
was from a real program. Also, try "x != 0" instead of "!!x" and see
if you get different results.

-- Jamie
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