Re: [PATCH 11/23] make atomic_read() and atomic_set() behaviorconsistent on m32r

From: Linus Torvalds
Date: Thu Aug 23 2007 - 16:13:29 EST




On Thu, 23 Aug 2007, Segher Boessenkool wrote:
>
> This simply isn't true. The compiler *can* combine asm stuff:

Please Segher, just shut up.

The combining, which I've mentioned *multiple*times* is

if (atomic_read(&x) <= 1)

and dammit, if that doesn't result in a *single* instruction, the code
generation is pure and utter crap.

It should result in

cmpl $1,offset(reg)

and nothing else. And there is no way in hell you are doing that with
"atomic_read()" being inline asm.

So can you now just go away?

Linus
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