Hi Clemens, For making my implementation of shared memory data structure more space efficient, I was trying to implement a stack which stores offsets to unused locations in the shared memory file. But as stack is being shared it also needs to be edited in a lock free way. While editing stack I need to atomically CAS both top of stack and the element on it. For this I found double compare and swap. Also, in my data structure at one point I need DCAS as well to ensure correct editing. To implement DCAS I came across some instruction “cmpxchg16”. But I think its still not as per my need. [1]
Do you know any alternative with which I can DCAS atomically or anything which atomically checks 2 old values before replacing value at an address? [1] https://stackoverflow.com/questions/7646018/sse-instructions-which-cpus-can-do-atomic-16b-memory-operations Regards, Mihir
