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cudagpu-shared-memory

Is there a way of setting default value for shared memory array?

Consider the following code:

__global__ void kernel(int *something) {
    extern __shared__ int shared_array[];     

    // Some operations on shared_array here.
}

Is it possible to initialize the whole shared_array to some value - e.g. 0 - without explicitly addressing each cell in some thread?

Solution

  • No. Shared memory is uninitialised. You have to somehow initialise it yourself, one way or another...

    From CUDA C Programming Guide 3.2, Section B.2.4.2, paragraph 2:

    __shared__ variables cannot have an initialization as part of their declaration.

    This also discards nontrivial default constructors for shared variables.