Re: [PATCH] document optimizing macro for translating PROT_ to VM_ bits

[Jamie Lokier]

Valdis.Kletnieks@xxxxxx wrote:
> Is this supposed to return the bitmask bit2, or (x & bit2)?  If the former,
> then your code is right.  If the latter,  (x & bit1) ? (x & bit2) : 0

The former.

> I'm totally failing to see why the original did the bit1 == bit2 compare,
> so maybe mhyself and Jamie are both missing some subtlety?

"bit1 == bit2" was an optimisation.  It made the machine code smaller,
without changing the result.

-- Jamie
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