warp.tile_stack_count

warp.tile_stack_count(s: Any) → int

Kernel

Return the current number of elements in a tile stack.

Unlike the other tile stack operations this function is not cooperative — it does not contain a synchronization barrier and may be called by a single thread or from within a divergent branch. It is safe to call after any tile_stack_push(), tile_stack_pop(), or tile_stack_clear() provided the preceding cooperative call has completed on all threads in the block. Those calls end with a barrier that makes count stable and visible. Calling this after a divergent push/pop/clear is undefined.

Parameters:

s – The tile stack

Returns:

The current number of elements in the stack.

Example

CAP = wp.constant(8)

@wp.kernel
def count_kernel(out_count: wp.array[int]):
    _i, j = wp.tid()
    s = wp.tile_stack(capacity=CAP, dtype=int)
    wp.tile_stack_push(s, j, j % 2 == 0)
    if j == 0:
        out_count[0] = wp.tile_stack_count(s)

out_count = wp.zeros(1, dtype=int)
wp.launch_tiled(count_kernel, dim=[1], inputs=[out_count], block_dim=8)

print(out_count.numpy()[0])

4