On Tue, 2011-12-20 at 01:13 +0100, Torvald Riegel wrote: > On Mon, 2011-12-19 at 15:17 -0800, Richard Henderson wrote: > > On 12/19/2011 02:58 PM, Torvald Riegel wrote: > > > In the particular case (the validated loads technique used in > > > method-gl.cc, load(), store(), and validate()), we actually do not need > > > to have loads or stores to be really atomic, but need the compiler to > > > treat them as if they were atomics wrt. to reordering etc. (e.g., wrt. > > > adjacent fences). Right now, I'm relying on the fact that GCC doesn't > > > optimize atomics yet and am just using nonatomic loads/stores. > > > > For 4.7, these accesses need to be volatile if they're to interact > > with the adjacent atomic ops. > > What do you mean by "interact"? AFAIU Andrew, currently atomics act as > full optimization barriers, leaving nonatomic memory accesses in place > somewhere between the surrounding atomic accesses.
Andrew, can you please comment on this? Full context: http://gcc.gnu.org/ml/gcc-patches/2011-12/msg01427.html
