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Bjorn Gustavsson
bjorn@REDACTED
Mon Mar 14 08:45:44 CET 2005
"Richard A. O'Keefe" <ok@REDACTED> writes:
[...]
>
> (2) Making a cons cell would no longer be a simple matter of bumping a
> register (the required check for overflow can be amortised over
> several allocations; I don't know whether it is or not) and filling
> in a couple of words. The length field has to be computed and stored
> as well. So the time to make *every* list goes up by 33% as well,
> maybe more.
The overflow test IS amortised over several allocations in Beam.
And as Richard C already noted in another mail, cons cell take up two words,
so the extra cost would be 50%.
/Bjorn
--
Björn Gustavsson, Erlang/OTP, Ericsson AB
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