Community
cancel
Showing results for 
Search instead for 
Did you mean: 
jseigh
Beginner
281 Views

cmpxchg16b

Rumor has it that Intel might drop cmpxchg16b. Is this true? It's still in the documentation the last time I checked.

Normally, you shouldn't really concern yourself with individual instructions as most programming is done with a compiled language. But if you're trying to implement various kinds of lock-free algorithms then individual instructions become important. Right now, Intel ia86-64 processors have a distinct advantage over AMD's processors.

Message Edited by hagabb on 10-04-2004 11:35 AM

0 Kudos
5 Replies
Chris_M__Thomasson
New Contributor I
281 Views



jseigh wrote:
Rumor has it that Intel might drop cmpxchg16b. Is this true? It's still in the documentation the last time I checked.

Normally, you shouldn't really concern yourself with individual instructions as most programming is done with a compiled language. But if you're trying to implement various kinds of lock-free algorithms then individual instructions become important. Right now, Intel ia86-64 processors have a distinct advantage over AMD's processors.

Oh, so very true!

Please, hardware folk... Don't cut off dwcas!?!?!?

:O

ClayB
Black Belt
281 Views



lockfree wrote:


jseigh wrote:
Rumor has it that Intel might drop cmpxchg16b. Is this true? It's still in the documentation the last time I checked.

Normally, you shouldn't really concern yourself with individual instructions as most programming is done with a compiled language. But if you're trying to implement various kinds of lock-free algorithms then individual instructions become important. Right now, Intel ia86-64 processors have a distinct advantage over AMD's processors.

Oh, so very true!


Has anyone got a published confirmation for this? Is this something that is available in Itanium, but not in the newer EM64T processors? Any pointers or other details would be most helpful.

--clay

jseigh
Beginner
281 Views


ClayB wrote:


Has anyone got a published confirmation for this? Is this something that is available in Itanium, but not in the newer EM64T processors? Any pointers or other details would be most helpful.


--clay







cmpxchg16b exists on Intel's IA32-64 processors not AMD's. The question is who blinks first, Intel or AMD? I suppose it's moot since I'm not upgrading to 64 bits until processor power requirements go back below 100 watts. By the time that happens I imagine the question will have been resolved and I'll just deal with whatever the outcome is. That that it matters.
Ichlasul_Affan
Beginner
281 Views

Is CMPXCHG16b available in Ivy Bridge? I need your help, because I'll install Windows 8.1 Preview in my Ivy Bridge Core i7-3537U Ultrabook. Thanks.

jimdempseyatthecove
Black Belt
281 Views

The 64-bit processor would be unable to perform a DCAS operation (pointer and ABA code). While you could use TSX or RTM without using DCAS, this would be short sighted of Intel to remove an instruction to force code change. This would break a lot of code.

Jim Dempsey