skaller <[EMAIL PROTECTED]> writes: > On Mon, 2007-11-05 at 09:56 -0800, Ian Lance Taylor wrote: > > skaller <[EMAIL PROTECTED]> writes: > > > > > Can someone tell me what optimisations might be enabled/disabled > > > by strict aliasing rules? > > > Strict aliasing only refers to loads and stores using pointers. > > Ah, I see. So turning it off isn't really all that bad > for optimisation.
It depends on the processor. For an in-order processor with a deep pipeline (e.g., Itanium, but there are others), the ability to reorder loads and stores is very important to permit scheduling flexibility. Strict aliasing reportedly makes a difference for x86, but I don't think it makes a huge difference. Ian
