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    SubjectRe: [RHEL5 PATCH 1/4] Provide fallback full 64-bit divide/modulus ops for gcc
    On Tue 15-08-06 09:29:57, David Howells wrote:
    > Andi Kleen <ak@suse.de> wrote:
    >
    > > At least Linus' traditional argument against this is that it's better
    > > to open code these (do_div) so that it's clear to the coder that they
    > > are really costly.
    >
    > do_div() is not a full replacement for __udivdi3(), __umoddi3() or
    > __udivmoddi4(), though I suspect we don't need divisor >= 2^32 anywhere atm.
    >
    > There are places where the compiler emits these that aren't entirely obvious,
    > one of which IIRC is in ext2 inode allocation.

    Well -- but that is good reason to keep that open-coded, right?

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