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Re: [v3 RFC] PATCH to memory asm ops in atomicity.h
On Tue, Dec 16, 2003 at 09:00:01PM -0500, Jason Merrill wrote:
> They're used for atomic access to a particular memory location. Why isn't
> it enough to specify that location directly?
If that is *all* they are used for, then fine. But if an
atomic increment is used to implement a mutex, then it is
not fine.
> Note also that the asms are marked volatile, which should prevent
> scheduling across them.
That only applies to scheduling. Not to cse or load-store motion or
any other optimization that shouldn't cross a thread synchronization
point.
r~