Using GMP for an ARM microcontroller project

[Décio Luiz Gazzoni Filho]

Hello,

First of all, I'll readily admit that I did absolutely no research on  
this topic, so it's likely that I'm asking dumb or obvious questions.  
Hence, feel free to ignore this question.

However, I wanted someone with experience running GMP on the ARM  
architecture to answer a couple of questions:

1. Does GMP run well (or at all) if an OS is not present? I'm  
planning to run the application directly on the chip, with no OS  
underneath.
2. What's the minimum footprint of the compiled code, if the code is  
optimized for size, unneeded functions are trimmed, etc.? I don't  
need an exact figure, just an approximation within 30%. Also, I  
realize this is dependent on the functionalities of GMP that are  
used, so I'll point out that it's a cryptographic application, so I  
should only use the arithmetic functions (add, sub, mul, div) of the  
mpz layer, perhaps some of the number theoretic functions as well,  
and I'll certainly disable the FFT code.
3. Does using the C++ class interface add too much to the footprint  
of the code?
4. Is there optimized code for the ARM7TDMI core?

Thanks in advance.

Décio