What instructions 'instCount' Pin tool counts?

Question

I run pintool \'instCount\' on basic C program with empty body within the main function.

int main() {

}

When I run the

Answer 1

What's missing is that behind the scenes, a lot of work is done to get you up to the point where the main() function is executed. There is a lot of work that the runtime needs to perform in order to provide the environment as you expect to get it. For example:

• Libraries must be loaded and initialized.
• Internal data structures (e.g. the dynamic memory allocator) need to be allocated and initialized.
• There are various factors in the environment that may change the way the runtime should be have. This needs to be checked and also acted upon.

The things I listed are just a very partial list of what happens during startup. Similar things occur during shutdown which also add to the instruction count.