llvm: improve emitted debug info

* ensure parameter debug info is in the subroutine di scope
* slit sub file path into basename and dirname

Closes #12257
Closes #12665
3357425b87Veikka Tuominen committed on 1/9/2023, 9:44:53 PM· committed by Andrew Kelleyparent5404d06
1 file changedLine totals unavailable