Using existing unit test frameworks with SystemC

Question

I am working on a project in SystemC and want to incorporate unit testing. Is it possible to use existing unit test frameworks with SystemC?

I ask this because it seems

Answer 1

Very often SystemC Device-under-test (DUT) can be resetted to initial state by asserting some signal. You can utilize this fact and enable any C++ unit testing framework you want. Just reset you DUT before running each test, so you don't need to elaborate it twice.

Here is an example with Google Test, and a simple "Accumulator" DUT

1. Initialize GTest (::testing::InitGoogleTest(&argc, argv);) from sc_main
2. Elaborate your model
3. Run tests from some thread inside sc_module by calling RUN_ALL_TESTS()
4. You will need somehow to pass pointer to SystemC DUT interface to your tests. I've used global variable for that purpose

Source:

#include 
#include "gtest/gtest.h"

struct test_driver;

test_driver *test_driver_p = nullptr;

void register_test_driver(test_driver *td) {
    test_driver_p = td;
}

test_driver* get_test_driver() {
    assert(test_driver_p);
    return test_driver_p;
}


SC_MODULE(dut_accum) {
    sc_in_clk   clk{"clk"};
    sc_in reset{"reset"};

    sc_in en{"en"};
    sc_in  din{"din"};
    sc_out dout{"dout"};

    SC_CTOR(dut_accum) {
        SC_METHOD(accum_method);
        sensitive << clk.pos();
    };

    void accum_method() {
        if (reset)
            dout = 0;
        else if (en)
            dout = dout + din;
    }
};

SC_MODULE(test_driver) {

    sc_signal reset{"reset",1};
    sc_signal en{"en",0};
    sc_signal din{"din",0};
    sc_signal dout{"dout"};

    SC_CTOR(test_driver) {
        dut_inst.clk(clk);
        dut_inst.reset(reset);
        dut_inst.en(en);
        dut_inst.din(din);
        dut_inst.dout(dout);
        SC_THREAD(test_thread);
        sensitive << clk.posedge_event();
        register_test_driver(this);
    }

private:
    void test_thread() {
        if (RUN_ALL_TESTS())
            SC_REPORT_ERROR("Gtest", "Some test FAILED");
        sc_stop();
    }

    dut_accum dut_inst{"dut_inst"};
    sc_clock clk{"clk", 10, SC_NS};
};



namespace {
    // The fixture for testing dut_accum
    class accum_test: public ::testing::Test {
    protected:

        test_driver & td;

        accum_test(): td(*get_test_driver()){
            reset_dut();
        }

        virtual ~accum_test() {}

        void reset_dut(){
            td.reset = 1;
            wait();
            td.reset = 0;
        }
    };

    TEST_F(accum_test, test0) {
        td.din = 10;
        td.en = 1;
        wait();
        wait();
        EXPECT_EQ(td.dout.read(), 10);
    }

    TEST_F(accum_test, test1_no_en) {
        td.din = 10;
        td.en = 0;
        wait();
        wait();
        EXPECT_EQ(td.dout.read(), 10); // this test will fail, since en is 0
    }

    TEST_F(accum_test, test2_reset_asserted) {
        td.din = 10;
        td.en = 1;
        td.reset = 1;
        wait();
        wait();
        EXPECT_EQ(td.dout.read(), 0);
    }
}

int sc_main(int argc, char **argv) {
    ::testing::InitGoogleTest(&argc, argv);
    test_driver td{"td"};
    sc_start();
}

CMakeLists.txt (requires installed SystemC 2.3.2 )

cmake_minimum_required(VERSION 3.8)
project(systemc_gtest)

find_package(SystemCLanguage CONFIG REQUIRED)

set (CMAKE_CXX_STANDARD ${SystemC_CXX_STANDARD})

find_package(GTest REQUIRED)

enable_testing()

add_executable(systemc_gtest main.cpp)
target_link_libraries(systemc_gtest ${GTEST_LIBRARIES} SystemC::systemc )
target_include_directories(systemc_gtest PRIVATE ${GTEST_INCLUDE_DIRS})
add_test(AllTestsInSystemCGtest systemc_gtest)