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    SubjectRe: [PATCH 1/2] x86: eliminate TS_XSAVE
    On 05/04/2010 09:24 PM, H. Peter Anvin wrote:
    > I would like to request one change, however. I would like to see the
    > alternatives code to be:
    > movb $0,reg
    > movb $1,reg
    > ... instead of using xor (which has to be padded with NOPs, which is of
    > course pointless since the slot is a fixed size.)


    > I would suggest using
    > a byte-sized variable instead of a dword-size variable to save a few
    > bytes, too.

    I used a bool, and the code already compiles to a byte mov. Though it
    could be argued that a word instruction is better since it avoids a
    false dependency, and allows a preceding instruction that modifies %reg
    to be executed after the mov instruction.

    > Once the jump label framework is integrated and has matured, I think we
    > should consider using it to save the mov/test/jump.

    IIRC that has an implied unlikely() which isn't suitable here?

    Perhaps the immediate values patches.

    error compiling committee.c: too many arguments to function

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      Last update: 2010-05-05 09:33    [W:0.026 / U:6.484 seconds]
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