Roland Schwarz escreveu:
2) atomicity better would be addressed by the compiler, given a suitable memory model, than as a library.
3) Despite 2) it would be possible to write a library, but it will be hard to get processor independent semantics. E.g. there is one concept of read/write/full memory barriers or another of acquire/release semantics for SMP.
5) Is it worth the effort to create a library with processor independent semantics, at the price of not being optimal? E.g. by doing away with the various kinds of barriers, instead simply requiring atomicity and full memory barrier semantics for the operation? Which operations, besides load and store would be essential?
The current working paper for the Standard Library contains chapter 29 "Atomic operations library". This chapter currently contains only a forward declaration (hehe) to the draft proposal by Hans Bohem. http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2006/n2047.html It's sister paper, "Sequencing and the concurrency memory model", is: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2006/n2052.htm -- Pedro Lamarão