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From: anton@mips.complang.tuwien.ac.at (Anton Ertl)
Newsgroups: comp.compilers
Subject: Re: how to find gc roots in stack machine?
Date: Mon, 01 Jul 2013 15:54:01 GMT
Organization: Institut fuer Computersprachen, Technische Universitaet Wien
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n.oje.bar@gmail.com writes:
>I am writing a simple compiler for a simple stack machine. Now I want
>to add a garbage collector. To do this I need a way to be able to find
>all roots in the stack at any given time (or at least at some special
>points in time).

Since you want it simple, my recommendation is one of:

A) Use a conservative GC (e.g., Boehm's).

B) Use a separate stack for pointers.  Then you know that everything
on that stack is a root (or null), and everything on the other stack
is not.  You still have complexity to identify roots in memory; so my
overall recommendation is A.

- anton
--
M. Anton Ertl
anton@mips.complang.tuwien.ac.at
http://www.complang.tuwien.ac.at/anton/