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    SubjectRe: [patch 02/12] Immediate Values - Architecture Independent Code
    On Mon, 28 Sep 2009 21:54:45 +0200
    Andi Kleen <andi@firstfloor.org> wrote:

    > > btw just to add to this:
    > > caches are unified code/data after L1 in general... it then does not
    > > matter much if you encode the "almost constant" in the codestream or
    > > slightly farther away, in both cases it takes up cache space.
    >
    > It does take up cache space, but when it's embedded in the instruction
    > stream the CPU has it usually already prefetched (CPUs are very good
    > at prefetching instructions). That's often not the case
    > with arbitary data accesses like this.

    this makes me wonder what happens when a variable is used in multiple
    places... that makes the icache overhead multiply right?


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    Arjan van de Ven Intel Open Source Technology Centre
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