Re: (64bit) push-pop puzzles

Dear all,

From the beginning of the 8086 until nowaday's still is using
as a NOP the following machine code:

xchg (r)(e)ax,(r)(e)ax

the problem with this kind of nop's is that the processor
can't optimize the NOP used (is used as a advanged too).

So when the processor load one NOP in the first pipeline
a next NOP in the second pipeline and so on all
the pipelines have to wait for the result of that xchg.
If you would put afther a nop something usefull the delay
would be less since the pipeline dos not have to wait for
the prefius one.

Succes, Tessa

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