Added check on last instruction

1 files changed, 19 insertions, 1 deletions

diff --git a/kvx/lib/RTLpathScheduleraux.ml b/kvx/lib/RTLpathScheduleraux.ml
index 5e9111d2..11539994 100644
--- a/kvx/lib/RTLpathScheduleraux.ml
+++ b/kvx/lib/RTLpathScheduleraux.ml
@@ -194,13 +194,31 @@ let change_predicted_successor i s = match i with
       | None -> failwith "Predicted a successor for an Icond with p=None - unpredicted CB should not be moved in the middle of the superblock"
       )
 
+(**
+ * Perform basic checks on the new order :
+ * - must have the same length as the old order
+ * - non basic instructions (call, tailcall, return, jumptable, non predicted CB) must not move
+ *)
+let check_order code old_order new_order = begin
+  assert ((Array.length old_order) == (Array.length new_order));
+  let length = Array.length new_order in
+  if length > 0 then
+    let last_inst = Array.get old_order (length - 1) in
+    let instr = get_some @@ PTree.get last_inst code in
+    match predicted_successor instr with
+    | None ->
+        if (last_inst != Array.get new_order (length - 1)) then
+          failwith "The last instruction of the superblock is not basic, but was moved"
+    | _ -> ()
+end
+
 let apply_schedule code sb new_order =
   let tc = ref code in
   let old_order = sb.instructions in
   let last_node = Array.get old_order (Array.length old_order - 1) in
   let last_successors = successors_inst @@ get_some @@ PTree.get last_node code in
   begin
-    assert ((Array.length old_order) == (Array.length new_order));
+    check_order code old_order new_order;
     Array.iteri (fun i n' ->
       let inst' = get_some @@ PTree.get n' code in
       let new_inst =