From 9d8a0be512031cc1e444c593641e4b54ff411dee Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?L=C3=A9onard=20G=C3=A9rard?= <leonard.gerard@ens.fr>
Date: Fri, 18 Nov 2011 11:56:02 +0100
Subject: [PATCH] Improve scalarize

---
 compiler/obc/transformations/scalarize.ml | 65 ++++++++++++-----------
 1 file changed, 35 insertions(+), 30 deletions(-)

diff --git a/compiler/obc/transformations/scalarize.ml b/compiler/obc/transformations/scalarize.ml
index a7a0812..07ccfc7 100644
--- a/compiler/obc/transformations/scalarize.ml
+++ b/compiler/obc/transformations/scalarize.ml
@@ -8,8 +8,8 @@
 (**************************************************************************)
 
 (** Remove implicit array's deep copy. If ever some p = e with p of type array still exist,
-  they are only used as reference to the array, no copy is implied :
-  array assignation after [scalarize] is pointer wise assignation *)
+    they are only used as reference to the array, no copy is implied :
+    array assignation after [scalarize] is pointer wise assignation *)
 
 
 open Misc
@@ -22,39 +22,44 @@ open Obc_mapfold
     This pass assumes that the backend when encountering t_ref = (e : int^n) will NOT COPY the array
     but set a reference to it. That's why it is declared as an alias.
     No t_ref is created if e was an extended value, no calculation is done, so it can be duplicated.
-    *)
+*)
 
 let fresh_for = fresh_for "scalarize"
 
 let act funs () a = match a with
-  | Aassgn (p,e) ->
+  | Aassgn (p, e) ->
       (match Modules.unalias_type e.e_ty with
-       | Types.Tarray (t, size) ->
-           let new_vd, new_eq, w_from_e = match e.e_desc with
-             | Eextvalue w -> [], [], w
-             | _ ->
-                 (* a reference (alias) to the array, since we have a full expression *)
-                 let array_ref = Idents.gen_var "scalarize" "a_ref" in
-                 let vd_array_ref = mk_var_dec ~alias:true array_ref p.pat_ty in
-                 (* reference initialization *)
-                 let pat_array_ref = mk_pattern ~loc:e.e_loc p.pat_ty (Lvar array_ref) in
-                 let init_array_ref = Aassgn (pat_array_ref, e) in
-                 [vd_array_ref], [init_array_ref], ext_value_of_pattern pat_array_ref
-           in
-           (* the copy loop with index [i] *)
-           let array_ref_i i = mk_ext_value_exp t (Warray (w_from_e, i)) in
-           let p_i i = mk_pattern t (Larray (p, i)) in
-           let copy_i i =
-             (* recursive call to deal with multidimensional arrays (go deeper) *)
-             let a = Aassgn (p_i i, array_ref_i i) in
-             let a, _ = act_it funs () a in
-             [a]
-           in
-           let copy_array = fresh_for (mk_exp_const_int 0) (mk_exp_static_int size) copy_i in
-           (* resulting block *)
-           let block = mk_block ~locals:new_vd (new_eq @ [copy_array]) in
-           Ablock block, ()
-       | _ -> raise Errors.Fallback
+        | Types.Tarray (t, size) ->
+            let new_vd, new_eq, w_from_e = match e.e_desc with
+              | Eextvalue w -> [], [], w
+              | _ ->
+              (* a reference (alias) to the array, since we have a full expression *)
+                  let array_ref = Idents.gen_var "scalarize" "a_ref" in
+                  let vd_array_ref = mk_var_dec ~alias: true array_ref p.pat_ty in
+                  (* reference initialization *)
+                  let pat_array_ref = mk_pattern ~loc: e.e_loc p.pat_ty (Lvar array_ref) in
+                  let init_array_ref = Aassgn (pat_array_ref, e) in
+                  [vd_array_ref], [init_array_ref], ext_value_of_pattern pat_array_ref
+            in
+            (* the copy loop with index [i] *)
+            let array_ref_i i = mk_ext_value_exp t (Warray (w_from_e, i)) in
+            let p_i i = mk_pattern t (Larray (p, i)) in
+            let copy_i i =
+              (* recursive call to deal with multidimensional arrays (go deeper) *)
+              let a = Aassgn (p_i i, array_ref_i i) in
+              let a, _ = act_it funs () a in
+              [a]
+            in
+            let copy_array = fresh_for (mk_exp_const_int 0) (mk_exp_static_int size) copy_i in
+            (* resulting block *)
+            (match new_vd, new_eq with
+              | [],[] ->
+                  copy_array
+              | _ ->
+                  let block = mk_block ~locals: new_vd (new_eq @ [copy_array]) in
+                  Ablock block, ()
+            )
+        | _ -> raise Errors.Fallback
       )
   | _ -> raise Errors.Fallback