How to get real code coverage with vsinstr / vsperfmon

my Microsoft based IDE looks like this: - huge native C ++ code split into 10 projects - each project has a dependent test project (GoogleTest unit tests), the sources for testing are just referenced.

I generated a coverage report using vsinstr and vsperfmon (visual studio tools for tooling / monitoring executables and DLLs), but that was not as satisfying as I expected because the report only shows unit-test line coverage, not from tested sources (I measured testuite-executable Sample_Project_Test.exe).

For example, if I have a method like this:

(Sample_Project/add_ints.cpp)

int add(int a, int b){
  return a+b;
}

int add2(int a, int b){
  if (a == b)
    return a * 2;
  else
    return a+b;
}

      

        
        
        
      

    

and the unit test looks like this:

(Sample_Project_Test/int_adds_tests.cpp)    

TEST(AddTest, ReturnsCorrectSum) 
{
  EXPECT_EQ(4, add(2,2));
}

      

        
        
        
      

    

I am getting 100% line coverage because only the added part in add_ints.cpp is measured, add 2 seems to be completely removed because it is not touched. As far as I misunderstood the whole coverage problem, does it seem wrong?