layout(local_size_x=LOCALSIZE) in;

layout(local_size_x=LOCALSIZE) in;

const uint groupSize=LOCALSIZE*BLOCKSIZE;

uniform uint elements;

layout(binding=2, std430) buffer countBuffer
{
uint maxSize;
uint count[];
};

layout(binding=3, std430) buffer globalSumBuffer
{
uint globalSum[];
};

shared uint groupSum[LOCALSIZE];

void main()
{
uint id=gl_LocalInvocationID.x;
uint dataOffset=gl_WorkGroupID.x*groupSize+id;
uint stop=dataOffset+groupSize;
uint sum=0u;
for(uint i=dataOffset; i < stop; i += LOCALSIZE)
sum += count[i];

groupSum[id]=sum;
barrier();

for(uint s=LOCALSIZE/2; s > 0u; s >>= 1u) {
if(id < s)
groupSum[id] += groupSum[id+s];
barrier();
}

if(id == 0u)
globalSum[gl_WorkGroupID.x]=groupSum[0u];
}