Re: Pros and cons of high-level intermediate languages

>[Somebody suggested that it might be possible to define some extensions to
>C that would make it easier to garbage collect. Any thoughts? -John]


In the interests of getting the obvious out of the way, the easiest
optimization is to allocate global and static local variables that point
to GC'able objects in a special data area that the GC system knows about.
Auto local can be dealt with by maintaining two stacks: non-pointer and
pointer, at a relatively minor cost.


This leaves, of course the minor problem of finding pointers inside of the
pointed-to structs. The much nastier problem of finding them inside of
unions is probably avoidable in the current case, as we're talking about
'C-as-intermediate-code', and the parent code-generator can presumably be
coded not to use unions.


Adding a '#pragma flush-registers' to deal with the optimizer seems to be
the only actual extension to the language that I can see. One would put
this just before a call to any function that could perform memory
allocation. Absent some kind of global optimizer, this would, of course,
be all of them, with a possibly non-trivial loss of performance.


Is there some simpler and cheaper technique I'm unaware of?
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