On Thu, Dec 11, 2014 at 1:08 AM, Andrew Haley <a...@redhat.com> wrote: > On 11/12/14 00:53, David Holmes wrote: >> There are many good uses of storestore in the various lock-free >> algorithms inside hotspot. > > There may be many uses, but I am extremely suspicious of how good > they are. I wonder if we went through all the uses of storestore in > hotspot how many bugs we'd find. As far as I can see (in the absence > of other barriers) the only things you can write before a storestore > are constants.
Hans has provided us with the canonical writeup opposing store-store and load-load barriers, here: http://www.hboehm.info/c++mm/no_write_fences.html Few programmers will be able to deal confidently with causality defying time paradoxes, especially loads from "the future".
