Re: [PATCH] lib: Make _find_next_bit helper function inline
From: Rasmus Villemoes
Date: Sun Aug 30 2015 - 17:47:38 EST
I've lost track of what's up and down in this, but now that I look at
this again let me throw in my two observations of stupid gcc behaviour:
For the current code, both debian's gcc (4.7) and 5.1 partially inlines
_find_next_bit, namely the "if (!nbits || start >= nbits)" test. I know it
does it to avoid a function call, but in this case the early return
condition is unlikely, so there's not much to gain. Moreover, it fails
to optimize the test to simply "if (start >= nbits)" - everything being
unsigned, these are obviously equivalent.
Rasmus
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