Wasm AST: add heap types 'struct', 'array' and 'none'

Author: vouillon

compiler/lib-wasm/code_generation.ml

@@ -161,19 +161,40 @@ let heap_type_sub (ty : W.heap_type) (ty' : W.heap_type) st =
   match ty, ty' with
   | Func, Func
   | Extern, Extern
-  | (Any | Eq | I31 | Type _), Any
-  | (Eq | I31 | Type _), Eq
-  | I31, I31 -> true, st
+  | (Any | Eq | Struct | Array | I31 | None_ | Type _), Any
+  | (Eq | Struct | Array | I31 | None_ | Type _), Eq
+  | (None_ | Struct), Struct -> true, st
+  | (None_ | Array), Array -> true, st
+  | (None_ | I31), I31 -> true, st
+  | None_, None_ -> true, st
+  | Type t, Struct ->
+      ( (let type_field = Hashtbl.find st.context.types t in
+         match type_field.typ with
+         | Struct _ -> true
+         | Array _ | Func _ -> false)
+      , st )
+  | Type t, Array ->
+      ( (let type_field = Hashtbl.find st.context.types t in
+         match type_field.typ with
+         | Array _ -> true
+         | Struct _ | Func _ -> false)
+      , st )
   | Type t, Type t' -> type_index_sub t t' st
+  | None_, Type t ->
+      ( (let type_field = Hashtbl.find st.context.types t in
+         match type_field.typ with
+         | Struct _ | Array _ -> true
+         | Func _ -> false)
+      , st )
   (* Func and Extern are only in suptyping relation with themselves *)
   | Func, _
   | _, Func
   | Extern, _
   | _, Extern
   (* Any has no supertype *)
   | Any, _
-  (* I31, struct and arrays have no subtype (of a different kind) *)
-  | _, (I31 | Type _) -> false, st
+  (* I31, struct, array and none have no other subtype *)
+  | _, (I31 | Type _ | Struct | Array | None_) -> false, st
 
 let register_global name ?exported_name ?(constant = false) typ init st =
   st.context.other_fields <-

compiler/lib-wasm/gc_target.ml

@@ -479,7 +479,7 @@ module Value = struct
     | W.RefI31 _ -> (
         match typ.typ with
         | W.I31 | Eq | Any -> return (W.Const (I32 1l))
-        | Type _ | Func | Extern -> return (W.Const (I32 0l)))
+        | Struct | Array | Type _ | None_ | Func | Extern -> return (W.Const (I32 0l)))
     | GlobalGet nm -> (
         let* init = get_global nm in
         match init with

compiler/lib-wasm/wasm_ast.ml

@@ -27,7 +27,10 @@ type heap_type =
   | Extern
   | Any
   | Eq
+  | Struct
+  | Array
   | I31
+  | None_
   | Type of var
 
 type ref_type =

compiler/lib-wasm/wasm_output.ml

@@ -172,13 +172,17 @@ end = struct
     res
 
   (****)
+
   let output_heaptype type_names ch typ =
     match (typ : heap_type) with
+    | None_ -> output_byte ch 0x71
     | Func -> output_byte ch 0x70
     | Extern -> output_byte ch 0x6F
     | Any -> output_byte ch 0x6E
     | Eq -> output_byte ch 0x6D
     | I31 -> output_byte ch 0x6C
+    | Struct -> output_byte ch 0x6B
+    | Array -> output_byte ch 0x6A
     | Type nm -> output_sint ch (Hashtbl.find type_names nm)
 
   let output_valtype type_names ch (typ : value_type) =

compiler/lib-wasm/wat_output.ml

@@ -150,7 +150,10 @@ let heap_type st (ty : heap_type) =
   | Extern -> Atom "extern"
   | Any -> Atom "any"
   | Eq -> Atom "eq"
+  | Struct -> Atom "struct"
+  | Array -> Atom "array"
   | I31 -> Atom "i31"
+  | None_ -> Atom "none"
   | Type t -> index st.type_names t
 
 let ref_type st { nullable; typ } =