Re: [PATCH] x86, bitops, variable_test_bit should return 1 not -1 on a match

[Prarit Bhargava]

On 08/21/2015 04:08 AM, H. Peter Anvin wrote:
> Wrong fix, though.  Instead we should change it to use the set instruction, which would also make it easier to use the CC_SET/CC_OUT proposed macros to use assembly out in the future.
> 
> The downside with set is that it only sets a single byte, the upside is that it always outputs 0 or 1, and apparently if the output variable is your bool gcc can use that for optimization.
> 

hpa -- can you send a pointer to that discussion?

Thanks,

P.
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