Clean-up: closures will not explicitly contain their arity

Author: vouillon

compiler/lib-wasm/gc_target.ml

@@ -22,8 +22,6 @@ open Code_generation
 
 type expression = Wasm_ast.expression Code_generation.t
 
-let include_closure_arity = false
-
 module Type = struct
   let value = W.Ref { nullable = false; typ = Eq }
 
@@ -215,13 +213,7 @@ module Type = struct
   let closure_common_fields ~cps =
     let* fun_ty = function_type ~cps 1 in
     return
-      (let function_pointer =
-         [ { W.mut = false; typ = W.Value (Ref { nullable = false; typ = Type fun_ty }) }
-         ]
-       in
-       if include_closure_arity
-       then { W.mut = false; typ = W.Value I32 } :: function_pointer
-       else function_pointer)
+      [ { W.mut = false; typ = W.Value (Ref { nullable = false; typ = Type fun_ty }) } ]
 
   let closure_type_1 ~cps =
     register_type
@@ -807,9 +799,9 @@ module Memory = struct
   let set_field e idx e' = wasm_array_set e (Arith.const (Int32.of_int (idx + 1))) e'
 
   let env_start arity =
-    if arity = 0
-    then 1
-    else (if include_closure_arity then 1 else 0) + if arity = 1 then 1 else 2
+    match arity with
+    | 0 | 1 -> 1
+    | _ -> 2
 
   let load_function_pointer ~cps ~arity ?(skip_cast = false) closure =
     let arity = if cps then arity - 1 else arity in
@@ -1082,15 +1074,9 @@ module Closure = struct
           { mut = false; typ = Type.value }
           (W.StructNew
              ( typ
-             , if arity = 0
-               then [ W.RefFunc f ]
-               else
-                 let code_pointers =
-                   if arity = 1 then [ W.RefFunc f ] else [ RefFunc curry_fun; RefFunc f ]
-                 in
-                 if include_closure_arity
-                 then Const (I32 (Int32.of_int arity)) :: code_pointers
-                 else code_pointers ))
+             , match arity with
+               | 0 | 1 -> [ W.RefFunc f ]
+               | _ -> [ RefFunc curry_fun; RefFunc f ] ))
       in
       return (W.GlobalGet name)
     else
@@ -1111,17 +1097,9 @@ module Closure = struct
           return
             (W.StructNew
                ( typ
-               , (if arity = 0
-                  then [ W.RefFunc f ]
-                  else
-                    let code_pointers =
-                      if arity = 1
-                      then [ W.RefFunc f ]
-                      else [ RefFunc curry_fun; RefFunc f ]
-                    in
-                    if include_closure_arity
-                    then W.Const (I32 (Int32.of_int arity)) :: code_pointers
-                    else code_pointers)
+               , (match arity with
+                 | 0 | 1 -> [ W.RefFunc f ]
+                 | _ -> [ RefFunc curry_fun; RefFunc f ])
                  @ l ))
       | (g, _) :: _ as functions ->
           let function_count = List.length functions in
@@ -1154,14 +1132,9 @@ module Closure = struct
             return
               (W.StructNew
                  ( typ
-                 , (let code_pointers =
-                      if arity = 1
-                      then [ W.RefFunc f ]
-                      else [ RefFunc curry_fun; RefFunc f ]
-                    in
-                    if include_closure_arity
-                    then W.Const (I32 (Int32.of_int arity)) :: code_pointers
-                    else code_pointers)
+                 , (if arity = 1
+                    then [ W.RefFunc f ]
+                    else [ RefFunc curry_fun; RefFunc f ])
                    @ [ env ] ))
           in
           if is_last_fun functions f
@@ -1247,13 +1220,7 @@ module Closure = struct
     in
     let* closure = Memory.wasm_cast cl_ty (load closure) in
     let* arg = load arg in
-    let closure_contents = [ W.RefFunc f; closure; arg ] in
-    return
-      (W.StructNew
-         ( ty
-         , if include_closure_arity
-           then Const (I32 1l) :: closure_contents
-           else closure_contents ))
+    return (W.StructNew (ty, [ W.RefFunc f; closure; arg ]))
 
   let curry_load ~cps ~arity m closure =
     let m = m + 1 in
@@ -1283,12 +1250,7 @@ module Closure = struct
       then [ W.RefFunc dummy_fun; RefNull (Type cl_typ) ]
       else [ RefFunc curry_fun; RefFunc dummy_fun; RefNull (Type cl_typ) ]
     in
-    return
-      (W.StructNew
-         ( ty
-         , if include_closure_arity
-           then Const (I32 1l) :: closure_contents
-           else closure_contents ))
+    return (W.StructNew (ty, closure_contents))
 end
 
 module Math = struct

runtime/wasm/effect.wat

@@ -45,7 +45,7 @@
    (type $block (array (mut (ref eq))))
    (type $bytes (array (mut i8)))
    (type $function_1 (func (param (ref eq) (ref eq)) (result (ref eq))))
-   (type $closure (sub (struct (;(field i32);) (field (ref $function_1)))))
+   (type $closure (sub (struct (field (ref $function_1)))))
    (type $function_3
       (func (param (ref eq) (ref eq) (ref eq) (ref eq)) (result (ref eq))))
    (type $closure_3

runtime/wasm/obj.wat

@@ -34,11 +34,9 @@
    (type $float (struct (field f64)))
    (type $float_array (array (mut f64)))
    (type $function_1 (func (param (ref eq) (ref eq)) (result (ref eq))))
-   (type $closure (sub (struct (;(field i32);) (field (ref $function_1)))))
-   (type $closure_last_arg
-      (sub $closure (struct (;(field i32);) (field (ref $function_1)))))
-   (type $function_2
-      (func (param (ref eq) (ref eq) (ref eq)) (result (ref eq))))
+   (type $closure (sub (struct (field (ref $function_1)))))
+   (type $closure_last_arg (sub $closure (struct (field (ref $function_1)))))
+   (type $function_2 (func (param (ref eq) (ref eq) (ref eq)) (result (ref eq))))
    (type $cps_closure (sub (struct (field (ref $function_2)))))
    (type $cps_closure_last_arg
       (sub $cps_closure (struct (field (ref $function_2)))))