register variable declaration question

[Dier Retlaw Semaj]

A question:

When should one declare a parameter to be a register variable?

For example:

int
wally(the_beav)
char 
	*the_beav;
{
	{ Lots of stuff using the_beav }
}

Am I missing the boat entirely on this matter?

Is there a cutoff point
where declaring the parameter to be a register variable is no longer efficient?

Should I immediately assign
the value of the parameter to a local register variable?

I have wondered this off & on for quite some time.
Thanks for your time.

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Dier R. Semaj	{ames,cmcl2,rutgers}!rochester!kodak!fedsys!wally!jwr

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