1 files changed, 45 insertions, 1 deletions
diff --git a/caml/RTLgenaux.ml b/caml/RTLgenaux.ml
index 336346a..61abecf 100644
--- a/caml/RTLgenaux.ml
+++ b/caml/RTLgenaux.ml
@@ -1,3 +1,47 @@
-open Cminor
+open Switch
+open CminorSel
 
 let more_likely (c: condexpr) (ifso: stmt) (ifnot: stmt) = false
+
+module IntOrd =
+  struct
+    type t = Integers.int
+    let compare x y =
+      if Integers.Int.eq x y then 0 else
+      if Integers.Int.ltu x y then -1 else 1
+  end
+
+module IntSet = Set.Make(IntOrd)
+
+let normalize_table tbl =
+  let rec norm seen = function
+  | CList.Coq_nil -> []
+  | CList.Coq_cons(Datatypes.Coq_pair(key, act), rem) ->
+      if IntSet.mem key seen
+      then norm seen rem
+      else (key, act) :: norm (IntSet.add key seen) rem
+  in norm IntSet.empty tbl
+
+let compile_switch default table =
+  let sw = Array.of_list (normalize_table table) in
+  Array.stable_sort (fun (n1, _) (n2, _) -> IntOrd.compare n1 n2) sw;
+  let rec build lo hi =
+    match hi - lo with
+    | 0 ->
+       CTaction default
+    | 1 ->
+       CTifeq(fst sw.(lo), snd sw.(lo), CTaction default)
+    | 2 ->
+       CTifeq(fst sw.(lo), snd sw.(lo),
+       CTifeq(fst sw.(lo+1), snd sw.(lo+1),
+       CTaction default))
+    | 3 ->
+       CTifeq(fst sw.(lo), snd sw.(lo),
+       CTifeq(fst sw.(lo+1), snd sw.(lo+1),
+       CTifeq(fst sw.(lo+2), snd sw.(lo+2),
+       CTaction default)))
+    | _ ->
+       let mid = (lo + hi) / 2 in
+       CTiflt(fst sw.(mid), build lo mid, build mid hi)
+  in build 0 (Array.length sw)
+