1 files changed, 76 insertions, 59 deletions

diff --git a/src/codegen.ml b/src/codegen.ml
index 316caa6..b1501fd 100644
--- a/src/codegen.ml
+++ b/src/codegen.ml
@@ -12,7 +12,6 @@ type whereis_var =
 type cg_env = {
   c_penv : env;
   c_names : whereis_var Smap.t;
-  c_ret_lbl : string;
   c_ret_ref : bool;
   c_fp_used : int;
 }
@@ -36,7 +35,7 @@ let rec gen_expr env e = match e.te_desc with
   | TEInt(k) -> li a0 k, false
   | TENull -> move a0 zero, false
   | TEThis -> (* convention : this is always the last-pushed argument *)
-    la a0 areg (8, fp), false
+    lw a0 areg (8, fp), false
   | TEIdent(i) ->
     begin match Smap.find i env.c_names with
     | VGlobal -> la a0 alab i, true
@@ -55,7 +54,7 @@ let rec gen_expr env e = match e.te_desc with
         assert (r || not byref);
         c ++ cr (r && not byref) ++ push a0 ++ code) nop args in
     code ++ jal id ++ popn (4 * (List.length args)), b
-  | TECallVirtual(obj, ti, fi, args, b) ->
+  | TECallVirtual(obj, fi, args, b) ->
     let code = List.fold_left
       (fun code (arg, byref) ->
         let c, r = gen_expr env arg in
@@ -63,15 +62,15 @@ let rec gen_expr env e = match e.te_desc with
         c ++ cr (r && not byref) ++ push a0 ++ code) nop args in
     let code2, a = gen_expr env obj in
     assert a;
-    code ++ code2 ++ push a0 ++ lw a0 areg (ti, a0) ++ lw a0 areg (fi, a0)
+    code ++ code2 ++ push a0 ++ lw a0 areg (0, a0) ++ lw a0 areg (fi, a0)
       ++ jalr a0 ++ popn (4 * (1 + List.length args)), b
   | TEUnary (x, e) ->
     let t, a = gen_expr env e in
     begin match x with
     | Ast.Deref -> t ++ cr a, true
     | Ast.Ref -> assert a; t, false
-    | Ast.Plus -> t, a
-    | Ast.Minus -> t ++ cr a ++ sub a0 zero oreg a0, false
+    | Ast.Plus -> t ++ cr a, false
+    | Ast.Minus -> t ++ cr a ++ neg a0 a0, false
     | Ast.Not -> t ++ cr a ++ not_ a0 a0, false
     | Ast.PreIncr -> assert a; t ++ lw a1 areg (0, a0) ++ add a1 a1 oi 1 ++ sw a1 areg (0, a0), true
     | Ast.PreDecr -> assert a; t ++ lw a1 areg (0, a0) ++ sub a1 a1 oi 1 ++ sw a1 areg (0, a0), true
@@ -100,10 +99,10 @@ let rec gen_expr env e = match e.te_desc with
       | Ast.Ge -> t1 ++ push a0 ++ t2 ++ pop a1 ++ sge a0 a1 a0
       | Ast.Land -> 
         let lazy_lbl = id "_lazy" in
-        t1 ++ beqz a0 lazy_lbl ++ t2 ++ label lazy_lbl 
+        t1 ++ beqz a0 lazy_lbl ++ t2 ++ label lazy_lbl ++ sne a0 a0 zero
       | Ast.Lor -> 
         let lazy_lbl = id "_lazy" in
-        t1 ++ bnez a0 lazy_lbl ++ t2 ++ label lazy_lbl
+        t1 ++ bnez a0 lazy_lbl ++ t2 ++ label lazy_lbl ++ sne a0 a0 zero
     ), false
   | TEMember(e, i) ->
     let c, a = gen_expr env e in
@@ -112,20 +111,18 @@ let rec gen_expr env e = match e.te_desc with
       c ++ la a0 areg (i, a0), true
     end else
       c, a
+  | TEPointerCast(e, i) ->
+    let c, a = gen_expr env e in
+    c ++ cr a ++ (if i = 0 then nop else la a0 areg (i, a0)), false
   | TENew(cls, constr, args) ->
-    let alloc = 
-      li v0 9 ++ li a0 cls.tc_size ++ syscall in
-    begin match constr with
-    | None -> alloc ++ (jal ("_c_" ^ cls.tc_name)), false
-    | Some x ->
-      let args_code = List.fold_left
-        (fun code (arg, byref) ->
-          let c, r = gen_expr env arg in
-          assert (r || not byref);
-          c ++ cr (r && not byref) ++ push a0 ++ code) nop args in
-      let c = args_code ++ alloc ++ push v0 ++ jal x in
-      c ++ pop a0 ++ popn (4 * List.length args), false
-    end
+    let args_code = List.fold_left
+      (fun code (arg, byref) ->
+        let c, r = gen_expr env arg in
+        assert (r || not byref);
+        c ++ cr (r && not byref) ++ push a0 ++ code) nop args in
+    let alloc = li v0 9 ++ li a0 cls.tc_size ++ syscall in
+    args_code ++ alloc ++ push v0 ++ jal constr  
+      ++ pop a0 ++ popn (4 * List.length args), false
     
 
 let rec gen_stmt env = function
@@ -134,8 +131,8 @@ let rec gen_stmt env = function
     comment "expr" ++ (fst (gen_expr env e)), nop, env
   | TSIf(cond, s1, s2) ->
     let c, a = gen_expr env cond in
-    let l_else = id "_cond" in
-    let l_end = id "_cond" in
+    let l_else = id "_cond_then" in
+    let l_end = id "_cond_end" in
     let c_then, d_then, _ = gen_stmt env s1 in
     let c_else, d_else, _ = gen_stmt env s2 in
     comment "if" ++ c ++ cr a ++ beqz a0 l_else ++ c_then ++ b l_end ++
@@ -165,46 +162,45 @@ let rec gen_stmt env = function
     let c, d = gen_block env b in
     comment "block" ++ c, d, env
   | TSReturn (None) ->
-    comment "return" ++ b env.c_ret_lbl, nop, env
+    comment "return" ++ b "_return", nop, env
   | TSReturn (Some e) ->
     let c, a = gen_expr env e in
     assert (a || not env.c_ret_ref);
-    comment "return" ++ c ++ cr (not env.c_ret_ref && a) ++ b env.c_ret_lbl, nop, env
+    comment "return" ++ c ++ cr (not env.c_ret_ref && a) ++ b "_return", nop, env
   | TSDeclare (ty, id) ->
     let s = type_size env.c_penv ty in
     let new_fp_used = env.c_fp_used + s in
     let pos = - new_fp_used in
     let code = match ty with
     | TClass(i) ->
+      let c = get_c env.c_penv i in
+      let cproto = List.find (fun p -> p.tp_ret_type = None && p.tp_name =  i && p.tp_args = []) c.tc_methods in
       sub sp sp oi s ++
-      la v0 areg (pos, fp) ++
-      jal ("_c_" ^ i)
+      la a0 areg (pos, fp) ++
+      push a0 ++
+      jal cproto.tp_unique_ident
     | _ -> push zero
     in
     comment ("declare " ^ id) ++ code, nop, {
       c_penv = env.c_penv;
       c_names = Smap.add id (VStack pos) env.c_names;
-      c_ret_lbl = env.c_ret_lbl;
       c_ret_ref = env.c_ret_ref;
       c_fp_used = new_fp_used }
   | TSDeclareAssignConstructor(cls, id, constr, args) ->
     let new_fp_used = env.c_fp_used + cls.tc_size in
     let pos = - new_fp_used in
-    let code = match constr with
-    | None -> sub sp sp oi cls.tc_size ++ move v0 sp ++ (jal ("_c_" ^ cls.tc_name))
-    | Some x ->
+    let code =
       let args_code = List.fold_left
         (fun code (arg, byref) ->
           let c, r = gen_expr env arg in
           assert (r || not byref);
           c ++ cr (r && not byref) ++ push a0 ++ code) nop args in
-      sub sp sp oi cls.tc_size ++ args_code ++ la a0 areg(pos, fp) ++ push a0 ++ jal x ++
+      sub sp sp oi cls.tc_size ++ args_code ++ la a0 areg(pos, fp) ++ push a0 ++ jal constr ++
           popn (4 * (List.length args + 1))
     in
     comment ("declare " ^ id) ++ code, nop, {
       c_penv = env.c_penv;
       c_names = Smap.add id (VStack pos) env.c_names;
-      c_ret_lbl = env.c_ret_lbl;
       c_ret_ref = env.c_ret_ref;
       c_fp_used = new_fp_used; }
   | TSDeclareAssignExpr ((ty, r), id, e) ->
@@ -214,10 +210,9 @@ let rec gen_stmt env = function
     let pos = - new_fp_used in
     let code, a = gen_expr env e in
     assert (a || not r);
-    comment ("declare " ^ id) ++ code ++ cr (a && not r) ++ push a0, nop, {
+    comment ("declare " ^ id) ++ sub sp sp oi 4 ++ code ++ cr (a && not r) ++ sw a0 areg (pos, fp), nop, {
       c_penv = env.c_penv;
       c_names = Smap.add id (if r then VStackByRef pos else VStack pos) env.c_names;
-      c_ret_lbl = env.c_ret_lbl;
       c_ret_ref = env.c_ret_ref;
       c_fp_used = new_fp_used }
   | TSWriteCout(sl) ->
@@ -260,50 +255,71 @@ let gen_decl tenv decl = match decl with
     let env = {
       c_penv = tenv;
       c_names = names;
-      c_ret_lbl = id "_ret";
       c_ret_ref = (match proto.tp_ret_type with | None -> false | Some(_, r) -> r);
       c_fp_used = 0;
       } in
     let code_for_constructor = match proto.tp_ret_type with
       | Some _ -> nop
       | None -> let cls_name = (match proto.tp_class with | Some k -> k | None -> assert false) in
-        la v0 areg (8, fp) ++ jal ("_c_" ^ cls_name)
+        lw v0 areg (8, fp) ++ jal ("_c_" ^ cls_name) in
+    let code_for_virtual = match proto.tp_virtual with
+      | Some (c, _) when c.h_pos <> 0 ->
+        lw a0 areg (8, fp) ++ la a0 areg (-c.h_pos, a0) ++ sw a0 areg (8, fp)
+      | _ -> nop
     in
     let text, data = gen_block env block in 
     label proto.tp_unique_ident ++
-    push fp ++ push ra ++ move fp sp ++ code_for_constructor ++
-    text ++ label env.c_ret_lbl ++
-    move sp fp ++ pop ra ++ pop fp ++ jr ra,
-    data
+    push fp ++ push ra ++ move fp sp ++ code_for_constructor ++ code_for_virtual ++
+    text ++ b "_return", data
   | TDClass(c) ->
+    (* Call default constructor of parent classes *)
+    let code_parents = List.fold_left
+      (fun code parent ->
+          let cn = parent.h_class in
+          let c = get_c tenv cn in
+          let proto = List.find (fun p -> p.tp_ret_type = None && p.tp_args = [] && p.tp_name = cn) c.tc_methods in
+          code ++ lw v0 areg(0, sp) ++ la v0 areg(parent.h_pos, v0) ++push v0 ++ jal proto.tp_unique_ident ++ popn 4)
+      nop c.tc_hier.h_supers in
+    let code_parents = if code_parents <> nop then push v0 ++ code_parents ++ pop v0 else nop in
     (* Build vtables and build constructor *)
-    let rec mk_cls_code hh =
+    let rec make_vtables hh =
+      (* calculate vtable contents *)
       let vtable_size = List.fold_left (fun k (p, _) -> max k (p+4)) 0 hh.h_vtable in
       let vtable_as_array = Array.make (vtable_size / 4) "_nothing" in
       List.iter (fun (p, s) -> vtable_as_array.(p/4) <- s.tp_unique_ident) hh.h_vtable;
       let vt_l = Array.to_list vtable_as_array in
-      let vtable = label ("_vt_" ^ c.tc_name ^ "_as_" ^ hh.h_class) ++
-        (if vt_l = [] then nop else address vt_l) in
-      let constructor_code = la a0 alab ("_vt_" ^ c.tc_name ^ "_as_" ^ hh.h_class)
+      (* code for vtable initialization *)
+      let vtable =
+        if vt_l = [] 
+          then nop 
+          else label ("_vt_" ^ c.tc_name ^ "_as_" ^ hh.h_class) ++ address vt_l in
+      let constructor_code = 
+        if vt_l = []
+          then sw zero areg (hh.h_pos, v0)
+          else la a0 alab ("_vt_" ^ c.tc_name ^ "_as_" ^ hh.h_class)
             ++ sw a0 areg (hh.h_pos, v0) in
-      let c = get_c tenv hh.h_class in
-      let init_code = Smap.fold
-        (fun _ (ty, pos) code ->
-          (match ty with
-            | TClass(s) ->
-              push ra ++ push v0 ++
-                la v0 areg (pos + hh.h_pos, v0) ++
-                jal ("_c_" ^ s) ++ pop v0 ++ pop ra
-            | _ -> sw zero areg (pos + hh.h_pos, v0)
-          ) ++ code) c.tc_members nop in
+      (* code for subclasses initialization *)
       List.fold_left
           (fun (vt, cc) sup ->
-            let mvt, mcc = mk_cls_code sup in
+            let mvt, mcc = make_vtables sup in
             vt ++ mvt, cc ++ mcc)
-          (vtable, constructor_code ++ init_code) hh.h_supers
+          (vtable, constructor_code) hh.h_supers
+    in
+    let vtables, vtable_init_code = make_vtables c.tc_hier in
+    let init_code_proper = Smap.fold
+      (fun _ (ty, pos) code ->
+        (match ty with
+          | TClass(s) ->
+            let cs = get_c tenv s in
+            let proto = List.find (fun p -> p.tp_ret_type = None && p.tp_args = [] && p.tp_name = s) cs.tc_methods in
+            push v0 ++
+              la a0 areg (pos, v0) ++ push a0 ++
+               jal proto.tp_unique_ident ++ popn 4 ++ pop v0
+          | _ -> sw zero areg (pos, v0)
+        ) ++ code) c.tc_members nop 
     in
-      let vt, cc = mk_cls_code c.tc_hier in
-      label ("_c_" ^ c.tc_name) ++ cc ++ jr ra, vt
+      label (c.tc_name ^ "0") ++ lw v0 areg (0, sp) ++ label ("_c_" ^ c.tc_name) 
+          ++ push ra ++ code_parents ++ vtable_init_code ++ init_code_proper ++ pop ra ++ jr ra, vtables
 
 
 let generate p =
@@ -314,6 +330,7 @@ let generate p =
     let text =
       label "main" ++ jal p.prog_main ++
       li v0 10 ++ syscall ++
+      label "_return" ++ move sp fp ++ pop ra ++ pop fp ++
       label "_nothing" ++ jr ra ++
       text in
     { text = text;