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From: muller@src.dec.com (Eric Muller)
Newsgroups: comp.lang.modula3
Subject: Re: garbage collection and fast allocation/deallocation
Message-ID: <1991Jun5.104518.8547@src.dec.com>
Date: 5 Jun 91 17:45:18 GMT
References: <9106051432.AA22607@riposte>
Sender: news@src.dec.com (News)
Reply-To: muller@src.dec.com (Eric Muller)
Organization: DEC Systems Research Center
Lines: 21

In article <9106051432.AA22607@riposte>, wyant@saber.com ask about
specialized allocators and deallocators.

The Modula-3 language does not offer direct support for that. However,
in SRC Modula-3, the runtime is written in Modula-3 and we give the
source. In particular, the interfaces RTHeap and RTHeapRep, and the
module RTHeap that implements them, are concerned with traced heap
management. 

There is nothing that prevents a program from using an alternative
implementation of RTHeap. This implementation could treat the
allocation requests differently based on the typecode of the referent
to allocate. It could also receive hints from the program, also based
on typecodes. It is also conceivable to use the current system for
some typecodes, and another one for other typecodes.

The current collector would not support very well 'free' methods, as
detecting the deallocated objects would imply a sweep of the heap.

-- 
Eric.