#include <iostream>

#include <s390intrin.h>

# include <htmxlintrin.h>

int do_transactional_operation(int* data, int value, bool go_deeper) {

    int depth = 0;

    //start transaction!

    if (__TM_simple_begin() ==  _HTM_TBEGIN_STARTED) {

        //do operation in TM!

        *data = value;

        //read the nestig depth

        depth = __builtin_tx_nesting_depth();

        if (go_deeper)

        {

            depth = do_transactional_operation(data, 888, false);

        }

        //commit!

        __TM_end(); 

    }

    return depth;

}

int do_non_transactional_operation()

{

        return __builtin_tx_nesting_depth();

}

int main() {

    int shared_data = 0;

    int transaction_depth_0 = do_non_transactional_operation();

    std::cout << "Transaction 0: " << transaction_depth_0  << "   Shared data: " << shared_data << std::endl;

    int transaction_depth_1 = do_transactional_operation(&shared_data, 777, false);

    std::cout << "Transaction 1: " << transaction_depth_1  << "   Shared data: " << shared_data << std::endl;

    int transaction_depth_2 = do_transactional_operation(&shared_data, 777, true);

    std::cout << "Transaction 2: " << transaction_depth_2  << "   Shared data: " << shared_data << std::endl;

    return 0;

}

Transaction 0: 0   Shared data: 0

Transaction 1: 1   Shared data: 777

Transaction 2: 2   Shared data: 888

cmake -DWITH_UNIT_TESTS=ON .

cmake --build .

storage/innobase/unittest/innodb_sync-t

cd mysql-test

./mtr --parallel=auto --suite=unit