Hopefully a proper fix to code motion below side exits + NO register renaming

1 files changed, 23 insertions, 0 deletions

diff --git a/scheduling/MyRTLpathScheduleraux.ml b/scheduling/MyRTLpathScheduleraux.ml
index 2cf58d2e..7afaeaa9 100644
--- a/scheduling/MyRTLpathScheduleraux.ml
+++ b/scheduling/MyRTLpathScheduleraux.ml
@@ -1525,6 +1525,29 @@ let scheduler f =
       (List.init (Array.length sb.instructions) (fun i -> i))
       PTree.empty
     in
+    let (sb, code, pm, next_free_pc, live_renames) =
+      if !Clflags.option_fpoormansssa then
+        (* Final restoration code was already inserted. *)
+        (sb, code, pm, next_free_pc, live_renames)
+      else
+        (* Ther combination of code motion below side exits WITHOUT register renaming may
+         * cause some restoration code to be necessary. Otherwise it is not safe to
+         * duplicate instructions.
+         * The final restoration code is special since it may insert below. *)
+        let final_restoration = final_restoration_code sb code live_renames in
+        let (sb, code, pm, next_free_pc, fwmap) = insert_code sb code pm final_restoration ~next_free_pc in
+        let live_renames =
+          PTree.fold
+            (fun acc pc insts ->
+              let pc' = apply_map' fwmap pc in
+              (* Remove final renames, which were just inserted *)
+              let insts = if Camlcoq.P.eq pc sb.instructions.(Array.length sb.instructions - 1) then [] else insts in
+              PTree.set pc' insts acc)
+            live_renames
+            PTree.empty
+        in
+        (sb, code, pm, next_free_pc, live_renames)
+    in
     let (to_insert_restoration, to_rename, next_free_reg) = restoration_instructions' sb code live_renames ~next_free_reg in
     let side_exit_pcs = side_exit_pcs sb code in
     let code = ListLabels.fold_left side_exit_pcs