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Re: volatile qualifier hurts single-threaded optimized case
Benjamin Kosnik wrote:
static inline _Atomic_word
__attribute__ ((__unused__))
- __exchange_and_add_dispatch(volatile _Atomic_word* __mem, int __val)
+ __exchange_and_add_dispatch(_Atomic_word* __mem, int __val)
Agreed, but doing this means that in the improvements to rope that
Richard (and Hans) also want we have to call __exchange_and_add and
__atomic_add directly, because in that case the involved memory
locations are volatile and have to remain like that per Hans desiderata,
I gather. More generally, the original __exchange_and_add and
__atomic_add could be used also together with volatile memory and now
calling the "old" functions becomes necessary, we should document that
somewhere (if it weren't for this reason, everyone should always go
through the dispatchers).
Paolo.