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    SubjectRe: [PATCH 06/14] Pramfs: Include files
    Date
    On Monday 22 June 2009, Jörn Engel wrote:
    > Four loops doing the same increment with different data types: long,
    > u64, we32 (wrong-endian) and we64. Compile with no optimizations.
    >
    > Results on my i386 notebook:
    > long: 453953 us
    > we32: 880273 us
    > u64: 504214 us
    > we64: 2259953 us
    > loops: 100000000

    (couldn't resist)

    The we64 number is artificially high because the glibc bswap_64
    implementation forces the conversion to be done on the stack.
    Using __builtin_bswap64 make this look more logical, and
    makes your point even stronger (on core 2, using -m32):

    long: 236792 us
    we32: 500827 us
    u64: 265990 us
    we64: 757380 us
    loops: 100000000

    Arnd <><
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