[gclist] Re: PPC & GC, or GC and threads

Stuart Yeates Stuart.Yeates@trimble.co.nz
Fri, 23 Jan 1998 11:04:48 +1300

John R Levine wrote:
> Correct me if I'm missing something, but it's my impression 
> that you're in trouble on any architecture if you combine GC 
> and preempted threads.  It's not just a problem on PPC and 
> other chips without direct addressing.  

I think the problem is better stated as "much of the compiler
optimization research to-date has made a subtly different set of
assumptions than is made in a conservatively garbage collected system."

There would appear to be no reason why optimizing compilers couldn't be
built to preserve the invariant that there always be a (complete)
pointer to every block of live memory.

Garbage collection is fundamentally about moving work from the
programmer to the computer, and the code generator is going to have
share some of that work. 

Stuart Yeates  --- stuart.yeates@trimble.co.nz
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