Lower the assume intrinsic to a MIR statement

compiler/rustc_borrowck/src/lib.rs

@@ -599,14 +599,14 @@ impl<'cx, 'tcx> rustc_mir_dataflow::ResultsVisitor<'cx, 'tcx> for MirBorrowckCtx
                     "Unexpected CopyNonOverlapping, should only appear after lower_intrinsics",
                 )
             }
-            StatementKind::Nop
+            // Only relevant for mir typeck
+            StatementKind::AscribeUserType(..)
+            // Doesn't have any language semantics
             | StatementKind::Coverage(..)
-            | StatementKind::AscribeUserType(..)
-            | StatementKind::Retag { .. }
-            | StatementKind::StorageLive(..) => {
-                // `Nop`, `AscribeUserType`, `Retag`, and `StorageLive` are irrelevant
-                // to borrow check.
-            }
+            // Takes a `bool` argument, and has no return value, thus being irrelevant for borrowck
+            | StatementKind::Assume(..)
+            // Does not actually affect borrowck
+            | StatementKind::StorageLive(..) => {}
             StatementKind::StorageDead(local) => {
                 self.access_place(
                     location,
@@ -616,7 +616,10 @@ impl<'cx, 'tcx> rustc_mir_dataflow::ResultsVisitor<'cx, 'tcx> for MirBorrowckCtx
                     flow_state,
                 );
             }
-            StatementKind::Deinit(..) | StatementKind::SetDiscriminant { .. } => {
+            StatementKind::Nop
+            | StatementKind::Retag { .. }
+            | StatementKind::Deinit(..)
+            | StatementKind::SetDiscriminant { .. } => {
                 bug!("Statement not allowed in this MIR phase")
             }
         }