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    SubjectRe: Improved Swapping Method In sort.c

    On Wednesday 2008-04-30 19:09, Soumyadip Das Mahapatra wrote:

    >Hello everybody, The swapping method (in function void u32_swap() line no.. 14
    >to 16) in lib/sort.c can be improved by using the following code *(u32 *)b ^=
    >*(u32 *)a ^= *(u32 *)b ^= *(u32 *)a instead of the code given.

    GCC is smart enough to optimize the current instructions into a
    bswap instruction or similar. While with xor, some are said to fail -
    and three xor operations are surely slower than a swap if there is
    a swap instruction.

    Never heard of that?

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      Last update: 2008-04-30 19:33    [W:0.018 / U:3.212 seconds]
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