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    SubjectRe: [patch/rfc 2/4] pcf875x I2C GPIO expander driver
    Jean Delvare wrote:
    > !!(value & (1 << offset))
    > is more efficiently written
    > (value >> offset) & 1
    >

    ... but not more efficiently implemented.

    Your version requires code to do the shift on live data at runtime.
    David's version lets the compiler create the mask once, at compile-time.



    b.g.

    --
    Bill Gatliff
    bgat@billgatliff.com

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