Memory

[Gusvinhal]

Hi everyone!

I have one question about the memory hierarchy. When I use the shared memory, the cores make a copy of data to local memory, work on them, and transfer back the result to shared memory or them work directly on data in shared memory?

Thank you very much!
Gustavo.

[sebraa]

As far as I am aware, the core never automatically copies data from shared memory to local memory or back. You need to handle that yourself.

Data can be located in shared memory, local memory or CPU registers.
The CPU can only work (add, subtract, multiply...) with values in the registers,
but in C code, you don't use them directly. The compiler will take care of it.

So when you add two variables in shared memory, they will be copied to the CPU registers,
added, then written back to shared memory. Local memory is not involved in this case.

[Gusvinhal]