Re: [PATCH GIT 0.6] make use of register variables & size_t

[Linus Torvalds <torvalds@osdl.org>]

On Mon, 25 Apr 2005, Matthias-Christian Ott wrote:
>
> But this makes, like "register", direct use of processor registers (it
> stores int arguments in eax, ebx, etc.).

No. It make _unlike_ "register", direct use of processor registers.

The "register" keyword does _not_ use processor registers. It's just 
syntactic fluff, and tells the compiler exactly one thing:

 - that the compiler should warn if you take the address of such a thing.

In addition, the compiler may generate code that takes it into account, 
which most likely means _worse_ code than if it didn't take it into 
account.

In contrast regparm() actually says something very relevant: it says that 
the function uses a totally different calling convention.

		Linus
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