Hi Stephen, Honestly I didn't think about it too deeply. I simply copied the same pattern that the x86-64 SSE2 code is using. If a second barrier is required, then I think it would be required in that path, too, and would represent a more general problem in the code.
Since this function is called Acquire_Store, I think that the single barrier is sufficient and that it's correctly placed. As an acquire, we want to make sure that no reads or writes from after the store actually happen before the store. There is complementary function called Release_Store which has a barrier before its store. /peter On Thursday, January 23, 2014 11:33:44 AM UTC-5, stephentu wrote: > > I think you might actually want two memory barriers, something like > > MemoryBarrier(); > *ptr = value; > MemoryBarrier(); > > your current solution prevents compiler reordering the store with > statements after, but what about statements before? > > > On Thu, Jan 23, 2014 at 11:20 AM, <[email protected] <javascript:>>wrote: > >> >> Comment #1 on issue 599 by [email protected]: Fails to compile for Intel Phi >> http://code.google.com/p/protobuf/issues/detail?id=599 >> >> Thanks Stephen. ICC supports GCC's inline assembly syntax. I've applied >> your suggestion and tested it. An updated patch is attached. >> >> /peter >> >> >> Attachments: >> atomicops_internals_x86_gcc.h.patch 658 bytes >> >> >> -- >> You received this message because this project is configured to send all >> issue notifications to this address. >> You may adjust your notification preferences at: >> https://code.google.com/hosting/settings >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Protocol Buffers" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected] <javascript:>. >> To post to this group, send email to [email protected]<javascript:> >> . >> Visit this group at http://groups.google.com/group/protobuf. >> For more options, visit https://groups.google.com/groups/opt_out. >> > > -- You received this message because you are subscribed to the Google Groups "Protocol Buffers" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/protobuf. For more options, visit https://groups.google.com/groups/opt_out.
