squiid/rust
1
0
Fork 0
Code Issues Pull requests Projects Activity

Assert that a return place is not used for indexing during integration

Browse source 
The inliner integrates call destination place with callee return place
by remapping the local and adding extra projections as necessary.

If a call destination place contains any projections (which is already
possible) and a return place is used in an indexing projection (most
likely doesn't happen yet) the end result would be incorrect.

Add an assertion to ensure that potential issue won't go unnoticed in
the presence of more sophisticated copy propagation scheme.
This commit is contained in:
Tomasz Miąsko 2020-11-07 00:00:00 +00:00
parent 0256d065d4
commit 89c3582d59
1 changed files with 6 additions and 0 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

6
compiler/rustc_mir/src/transform/inline.rs
View file

@ -742,6 +742,12 @@ impl<'a, 'tcx> MutVisitor<'tcx> for Integrator<'a, 'tcx> {
}
fn visit_place(&mut self, place: &mut Place<'tcx>, context: PlaceContext, location: Location) {
for elem in place.projection {
// FIXME: Make sure that return place is not used in an indexing projection, since it
// won't be rebased as it is supposed to be.
assert_ne!(ProjectionElem::Index(RETURN_PLACE), elem);
}
// If this is the `RETURN_PLACE`, we need to rebase any projections onto it.
let dest_proj_len = self.destination.projection.len();
if place.local == RETURN_PLACE && dest_proj_len > 0 {