[Gcl-devel] counting allocated bytes

[Stephen Wilson]

Hello,

I have been working on evaluating/integrating a Lisp based testing
framework into Axiom (based on Lift).  One of the features is the
ability to benchmark the running of tests.  

To accommodate the benchmark code, I needed a function which returns
the total number of bytes allocated since the image was started.  

I could not find such a function.  Perhaps I missed it? There is
SI:ALLOCATED, but it reports information for a specific type only.

I considered writing a function using SI:ALLOCATED and SI:SIZE-OF for
personal use.  However, when I considered if such a function would be
of use to GCL, I realized it may be better to attempt it in C.

Of course, if the facility already exists, then this is just a
learning experience for me.  Attached is a patch against alloc.c.

I have two issues with this code:

  * Is it correct to assume that all entries in tm_table with the
    tm_size field equal share the same allocation space?  I assumed
    this from the documentation for SI:ALLOCATED.

  * Im slightly concerned about overflow of the `bytes' variable.  Is
    this likely?  Should bignum arith be used?

Hopefully this might be of some use to GCL, however I completely
understand if it is deemed unnecessary, badly implemented, etc.

Sincerely,
Steve

alloc.c.patch
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