[Python-Dev] Why is Bytecode the way it is?

[Greg Ewing]

Skip Montanaro <skip at pobox.com>:

> When I looked at this a long time ago it I seem to recall that roughly 60%
> of the opcodes executed did nothing more than copy values to or from the
> stack (of course, pushes and pops are some of the more efficient opcodes in
> the instruction set).  A three-address machine model would reduce this data
> movement substantially.

But it would only be worth doing if the cost of these data
movements is a substantial fraction of the whole execution
time. Does anyone have any timings to suggest that they
are?

Greg Ewing, Computer Science Dept, +--------------------------------------+
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