Improve metaprogramming codegen

[victor-eds]

Describe the bug

cgeist does not handling metaprogramming correctly, as the functions being passed as arguments to other functions are not defined, only declared, in the output module.

To Reproduce

Run:

cgeist -S -o - -O3 <file>

in both provided tests. You'll see how the functions being passed are not defined.

int square(int x) {
  return x*x;
}

int meta(int (*f)(int), int x) {
  return f(x);
}

int main() {
  meta(square, 3);
}

#include <iostream>

template <typename T, typename F>
T call(F func) {
  return func();
}

void foo() {
  std::cout << "Hello\n";
}

int main() {
  call<void>(foo);
}

Additional context:

We may want to use this operation defined in upstream polygeist as getting the address of a function is a C/C++ construct.

Environment (please complete the following information):

• DPC++ version: f719bf86fb12

[github-actions[bot]]

This issue is stale because it has been open 180 days with no activity. Remove stale label or comment or this will be automatically closed in 30 days.

[github-actions[bot]]

This issue was closed because it has been stalled for 30 days with no activity. Please, re-open if the issue still exists.