Re: Executing machine code?

[Samuel Mize <smize@imagin.net>]

Ikram <ikram@cs.und.ac.za> wrote:
> I occasionally need to write programs that generate and execute
> machine code (as in e.g. genetic programming systems).  in C, the
> method I've been using is to store the machine instructions in an
> array of bytes, and then cast the array into a function, e.g.:

My word.  I doubt you'll find a large body of people with experience
in this area.  :-)

> I'm trying to find out whether it is similarly possible to switch
> between array and function representations in Ada (not necessarily in
> a platform- or compiler-independent way).

I think you can accomplish what you want, at least with some compilers.
You'll need a compiler that supports the syntax for machine-language
instructions.  Write a routine that determines the address of the
first byte in your array of bytes, and then does a machine-language
subroutine jump to that address.

I specify "first byte in the array" because some compilers, at least
some older Ada 83 compilers, may return the address of a dope vector
if you just use 'address.

You may need to decide where to put the array in memory, and use a
representation clause to put it there.

Best of luck, and let us know how it works out!

Sam Mize

-- 
Samuel Mize -- smize@imagin.net (home email) -- Team Ada
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