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From: "Thierry Lelegard" <lelegard@club-internet.fr>
Subject: Re: Why parameter passing by copy?
Date: 2000/05/27
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> Ada requires that scalars be passed by copy. I was under the impression
> that this was chosen because it was faster, but i've never seen a 
> rational argument for this from the Ada83 perspective of computer
> hardware, nor whether such arguments still hold true for modern 
> processors.

On the contrary, it is even more true for modern processors
than for old ones.

For fast RISC processors, memory is a "slow device". Accessing
a datum in memory (passing the address) is much slower than
passing it in a register (by copy). Most calling standards for
RISC processors pass the arguments (or the first N arguments)
in registers.

________________________________________________________
Thierry Lelegard, Paris, France
E-mail: lelegard@club-internet.fr