Messages in this thread | | | Date | Fri, 10 Aug 2012 14:51:49 +0200 (CEST) | From | Jan Engelhardt <> | Subject | Re: [PATCH] MPILIB: Provide count_leading/trailing_zeros() based on arch functions |
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On Saturday 2012-07-21 02:46, David Miller wrote: >> Arnd Bergmann <arnd@arndb.de> wrote: >> >>> I don't generally like to put stuff into asm-generic when it's unlikely >>> to be overridden by architectures. It would really belong into >>> include/linux, but then again we have all the other bitops in asm-generic >>> as well, so whatever... >> >> Some arches (such as Sparc, I think) have count-leading-zero instructions. > >Yes, newer sparc64 chips have leading-zero-detect, and I was pretty >sure that powerpc had something similar. It's called count-leading- >zeros or something like that.
And gcc has a __builtin_clz.
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