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    SubjectRe: [PATCH] no need to check for NULL before calling kfree() -fs/ext2/
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    Marcin Dalecki <martin@dalecki.de> said:
    > On 2005-03-27, at 00:21, linux-os wrote:
    > > Always, always, a call will be more expensive than a branch
    > > on condition.

    Wrong.

    > > It's impossible to be otherwise.

    Many, many counterexamples say otherwise...

    > > A call requires
    > > that the return address be written to memory (the stack),

    Not necesarily right now, it can be done at leisure later on while doing
    other stuff.

    > > using register indirection (the stack-pointer).

    So what? The stack pointer is surely special. Modern programming languages
    (and programming styles) encourage many calls, so this is very heavily
    optimized.

    > Needless to say that there are enough architectures out there, which
    > don't even have something like an explicit call as separate assembler
    > instruction...

    The mechanism exists somehow.
    --
    Dr. Horst H. von Brand User #22616 counter.li.org
    Departamento de Informatica Fono: +56 32 654431
    Universidad Tecnica Federico Santa Maria +56 32 654239
    Casilla 110-V, Valparaiso, Chile Fax: +56 32 797513
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