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


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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