construct/include/ircd/simt/broadcast.h

// Matrix Construct
//
// Copyright (C) Matrix Construct Developers, Authors & Contributors
// Copyright (C) 2016-2021 Jason Volk <jason@zemos.net>
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice is present in all copies. The
// full license for this software is available in the LICENSE file.

/// Broadcast originating from the local leader (index [0]). All threads in the
/// group participate.
inline void
ircd_simt_broadcast_f4lldr(__local float4 *const buf)
{
	const uint
	li = get_local_id(0),
	ln = get_local_size(0);

	for(uint stride = 1; stride < ln; stride <<= 1)
	{
		if(li < stride)
			buf[li + stride] = buf[li];

		barrier(CLK_LOCAL_MEM_FENCE);
	}
}