compiler/rustc_mir_dataflow/src/un_derefer.rs

   1 use rustc_data_structures::fx::FxHashMap;
   2 use rustc_middle::mir::*;
   3 use rustc_middle::ty::TyCtxt;
   4
   5 /// Used for reverting changes made by `DerefSeparator`
   6 pub struct UnDerefer<'tcx> {
   7     pub tcx: TyCtxt<'tcx>,
   8     pub derefer_sidetable: FxHashMap<Local, Place<'tcx>>,
   9 }
  10
  11 impl<'tcx> UnDerefer<'tcx> {
  12     #[inline]
  13     pub fn derefer(&self, place: PlaceRef<'tcx>, body: &Body<'tcx>) -> Option<Place<'tcx>> {
  14         let reffed = self.derefer_sidetable.get(&place.local)?;
  15
  16         let new_place = reffed.project_deeper(place.projection, self.tcx);
  17         if body.local_decls[new_place.local].is_deref_temp() {
  18             return self.derefer(new_place.as_ref(), body);
  19         }
  20         Some(new_place)
  21     }
  22 }