auto_reduce.hpp

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// Copyright (c) 2021 - 2023 SparseLinearAlgebra
// Autogenerated file, do not modify
 
#pragma once
 
static const char source_reduce[] = R"(
 
 
// wave-wide reduction in local memory
void reduction_group(uint                   block_size,
                     uint                   lid,
                     volatile __local TYPE* s_sum) {
    if (BLOCK_SIZE >= block_size) {
        if (lid < (block_size / 2)) {
            s_sum[lid] = OP_BINARY(s_sum[lid], s_sum[lid + (block_size / 2)]);
        }
        if (block_size > WARP_SIZE) {
            barrier(CLK_LOCAL_MEM_FENCE);
        }
    }
}
 
__kernel void reduce(__global const TYPE* g_vec,
                     __global TYPE*       g_sum,
                     const TYPE           init,
                     const uint           n) {
    const uint gid   = get_group_id(0);
    const uint gsize = get_global_size(0);
    const uint lsize = get_local_size(0);
    const uint lid   = get_local_id(0);
 
    __local TYPE s_sum[BLOCK_SIZE];
    TYPE         sum = init;
 
    const uint gstart = gid * lsize;
 
    for (uint i = gstart + lid; i < n; i += gsize) {
        sum = OP_BINARY(sum, g_vec[i]);
    }
 
    s_sum[lid] = sum;
    barrier(CLK_LOCAL_MEM_FENCE);
 
    reduction_group(1024, lid, s_sum);
    reduction_group(512, lid, s_sum);
    reduction_group(256, lid, s_sum);
    reduction_group(128, lid, s_sum);
    reduction_group(64, lid, s_sum);
    reduction_group(32, lid, s_sum);
    reduction_group(16, lid, s_sum);
    reduction_group(8, lid, s_sum);
    reduction_group(4, lid, s_sum);
    reduction_group(2, lid, s_sum);
 
    if (lid == 0) {
        g_sum[gid] = s_sum[0];
    }
}
)";