Messages in this thread | | | Date | Thu, 03 Apr 2008 20:19:59 +0300 | From | Benny Halevy <> | Subject | Re: [0/3] Improve generic fls64 for 64-bit machines |
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On Mar. 15, 2008, 19:29 +0200, Alexander van Heukelum <heukelum@mailshack.com> wrote: > This series of patches: > > [1/3] adds __fls.h to asm-generic > [2/3] modifies asm-*/bitops.h for 64-bit archs to implement __fls > [3/3] modifies asm-generic/fls64.h to make use of __fls
I strongly support this.
I wish we'd also have a consistent naming convention for all the bitops functions so it will be clearer what data type the function is working on and is the result 0 or 1 based.
It seems like what we currently have is:
name type first bit# ---- ---- ---------- ffs int 1 fls int 1 __ffs ulong 0 __fls ulong 0 # in your proposal ffz ulong 0 fls64 __u64 1
so it seems like - ffz is misnamed and is rather confusing. Apprently is should be renamed to __ffz.
- (new) ffz(x) can be defined to ffs(~(x))
- It'd be nice to have ffs64, and maybe ffz64.
Benny
> > I have compiled i386 and x86_64, and they generate the same code as > before the change. The changes to the other archs are a best effort. > Please comment. > > If this patch series is accepted, it will make one tiny bit of > the x86-unification a tiny bit cleaner. The patches are against > Linus' current tree. > > Andrew, if no concensus can be reached that this is a bad patch > series, would you be willing to add this to your tree? > > Greetings, > Alexander > -- > 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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