Memory Models

[Clyde Smith-Stubbs]

>From article <10744 at smoke.BRL.MIL>, by gwyn at smoke.BRL.MIL (Doug Gwyn):
> People who aren't "wedded" to the *86 architecture generally don't
> seem to think it was necessary to cause memory models to be visible
> in higher-level programming languages.

There are probably more 80x86 processors out there than any other,
and the 80x86 architecture has brought C and Unix within reach of  people
who would not have access to it otherwise. That doesn't alter the fact that
its memory organization is horrible, but it should be some incentive to
devise rational, portable  techniques of managing address spaces that are
not linear.

> The Apple IIGS architecture
> (65816) has a similar trade-off, and the available C compilers for
> it do not have "near" and "far" foolishness.  And yes, it is
> possible for am Apple IIGS C programmer to select which model is to
> be used for his application, at least with Orca/C.


Actually, the 65816 is a prime example of a processor that cries out
for far and near pointers. The lack of them in the very few compilers
available for the IIgs is just that, a lack, not a feature. 

Hopefully there won't be too many more processors designed that have
architectures like the 80x86 and 65xxx, but I wouldn't like to put
money on it.
-- 
Clyde Smith-Stubbs
HI-TECH Software, P.O. Box 103, ALDERLEY, QLD, 4051, AUSTRALIA.
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