Register Addresses
Root Boy Jim
rbj at icst-cmr
Fri Jul 11 00:54:00 AEST 1986
RBJ-> >But Wait! That's a Mimic! Register variables are really fast auto
>variables, so after `f' returns, your static_p is worthless anyhow.
Gwyn-> But the objection is still valid. If the compiler were to fake up
some addressable storage for a copy of a register variable, then
afterward it would need to ensure that the contents of that location
track the contents of the register, since the pointer could then be
legitimately used to refer to the data in the register. This would
negate the whole point of "register".
Would it? Okay, so we have to pushmi-pullyu the register anytime we
call any function, or reference any global variable starwise, or
perhaps reference either the result of the function or even any
arguments originally passed by reference.
This is starting to get compilicated! Anyone for a 500k C Compiler?
It would probably still be smaller and faster than ADA :-)
Dennis knew what he was doing. The restriction of & applied to a
register variable is deliberate and sensible.
I agree. I was merely speculating on the tradeoff's involved.
So when are they going to start making droids with addressable registers again?
(Root Boy) Jim Cottrell <rbj at icst-cmr.arpa>
He is the MELBA-BEING...the ANGEL CAKE...XEROX him...XEROX him --
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