//
// This confidential and proprietary software may be used only as
// authorised by a licensing agreement from ARM Limited
// (C) COPYRIGHT 2020-2024 ARM Limited
// ALL RIGHTS RESERVED
// The entire notice above must be reproduced on all authorised
// copies and copies may only be made to the extent permitted
// by a licensing agreement from ARM Limited.


// The following array is used to check compliance that an output position
// is modified at most once.
bool_t output_modified[N,K,C];

// Copy the values_in tensor to the values_out tensor.
// Values not written by the scatter operation are unchanged in the output.
for_each(0 <= n < N, 0 <= k < K, 0 <= c < C) {
    in_out_t value = tensor_read<in_out_t>(values_in, [N,K,C], [n,k,c]);
    tensor_write<in_out_t>(values_out, [N,K,C], [n, k, c], value);
    output_modified[n,k,c]=false;
}

// Now perform the SCATTER operation, modifying the positions from the indices tensor
for_each(0 <= n < N, 0 <= w < W, 0 <= c < C) {
    index_t k = tensor_read<index_t>(indices, [N,W], [n,w]);
    REQUIRE(0 <= k && k < K);
    REQUIRE(output_modified[n,k,c] == false);
    in_out_t value = tensor_read<in_out_t>(input, [N,W,C], [n,w,c]);
    tensor_write<in_out_t>(values_out, [N,K,C], [n, k, c], value);
    output_modified[n,k,c] = true;
}