Lowering of nested break/continue in loops

[yugr]

Looks like currently CIRLoopOpLowering does not lower the nested break/continue statements within the lowered loop. For example this program

#include <stdio.h>

int foo(int n) {
  int s = 0, i;
  for (i = 1; i < n; ++i) {
    if (i == 1)
      break;
    ++s;
  }
  return s;
}

int main() {
  int s = foo(10);
  printf("%d\n", s);
  return 0;
}

prints 9 instead of expected 0.

Probably the best way to fix this is to scan body region inside CIRLoopLowering, replacing break/continue yields with BrOps?

[bcardosolopes]

Thanks for catching this. @sitio-couto seems like you are going to hit this sooner or later!

[yugr]

Probably the best way to fix this is to scan body region inside CIRLoopLowering, replacing break/continue yields with BrOps?

We did this and it seems to work fine. I think we should be able to send PR in few days if you are ok with this approach.

[bcardosolopes]

We did this and it seems to work fine. I think we should be able to send PR in few days if you are ok with this approach.

PRs are great :)

For full context, ideally we should lower those to a more simple form of CIR before LLVM lowering happens, so we can keep LLVM lowering a bit more simple. However, there are other changes we'd need before that in general and looks like your approach would work for now, so I'm ok with it. Let's just make sure you and @sitio-couto coordinate a bit to prevent dup work (we're also on discord if you'd like to discuss any other aspect).

[sitio-couto]

Let's just make sure you and @sitio-couto coordinate a bit to prevent dup work

@yugr I haven't reached unstructured loops yet. Feel free to work on this!