Fix miscompilation in comballoc for local allocations (#829)

ocaml-flambda · Sep 14, 2022 · 555728f · 555728f
1 parent 9beb63a
commit 555728f
Showing 1 changed file with 9 additions and 0 deletions.
diff --git a/backend/comballoc.ml b/backend/comballoc.ml
@@ -75,6 +75,15 @@ let rec combine i allocstate =
       let newnext = combine_restart i.next in
       (instr_cons_debug i.desc i.arg i.res i.dbg newnext,
        allocstate)
+  | Iop(Ibeginregion|Iendregion) -> begin
+      match allocstate with
+      | Pending_alloc { mode = Alloc_local; _ } ->
+          let newnext = combine_restart i.next in
+          (instr_cons_debug i.desc i.arg i.res i.dbg newnext, allocstate)
+      | No_alloc | Pending_alloc { mode = Alloc_heap; _ } ->
+          let newnext, s' = combine i.next allocstate in
+          (instr_cons_debug i.desc i.arg i.res i.dbg newnext, s')
+    end
   | Iop _ ->
       let (newnext, s') = combine i.next allocstate in
       (instr_cons_debug i.desc i.arg i.res i.dbg newnext, s')