#version 310 es
layout(local_size_x = 4, local_size_y = 4) in;

shared float foo[4][4];

layout(binding = 0, std430) buffer SSBO
{
	float out_data[];
};

void work()
{
	foo[gl_LocalInvocationID.x][gl_LocalInvocationID.y] = float(gl_LocalInvocationIndex);
	memoryBarrierShared();
	barrier();

	float x = 0.0;
	x += foo[gl_LocalInvocationID.x][0];
	x += foo[gl_LocalInvocationID.x][1];
	x += foo[gl_LocalInvocationID.x][2];
	x += foo[gl_LocalInvocationID.x][3];
	out_data[gl_GlobalInvocationID.x] = x;
}

void main()
{
	work();
}