Function get_splits

src/simplify_algebra.cpp:1119–1157

Search for multiple "slice" instructions in an instruction's outputs * which are contiguous slices of the same tensor. */

 *  which are contiguous slices of the same tensor.
 */
static std::vector<instruction_ref> get_splits(instruction_ref ins)
{
    std::vector<instruction_ref> result;
    std::copy_if(ins->outputs().begin(),
                 ins->outputs().end(),
                 std::back_inserter(result),
                 [&](auto i) { return i->name() == "slice"; });
    if(result.size() < 2)
        return {};
    auto get_slice = [](auto& i) -> auto& { return any_cast<op::slice>(i->get_operator()); };
    auto&& axes    = get_slice(result.front()).axes;

    // "slice" instructions must all have the same axes
    if(std::any_of(result.begin(), result.end(), [&](auto i) { return get_slice(i).axes != axes; }))
        return {};
    auto get_start = [&](auto& i) -> auto& { return get_slice(i).starts; };
    auto get_end   = [&](auto& i) -> auto& { return get_slice(i).ends; };

    // Sort the "slice" instructions in order of starts
    std::sort(
        result.begin(), result.end(), [&](auto x, auto y) { return get_start(x) < get_start(y); });
    if(std::any_of(get_start(result.front()).begin(), get_start(result.front()).end(), [&](auto i) {
           return i != 0;
       }))
        return {};

    // one slice must "start" where the last slice "end"
    auto it = std::adjacent_find(
        result.begin(), result.end(), [&](auto x, auto y) { return get_end(x) != get_start(y); });
    if(it != result.end())
        return {};
    for(std::size_t i = 0; i < axes.size(); i++)
    {
        auto axis = axes[i];
        if(ins->get_shape().lens()[axis] != get_slice(result.back()).ends[i])
            return {};
    }
    return result;
}

struct find_splits
{