[interpreter] Add boilerplate for ref.exn result patterns

interpreter/exec/eval.ml

@@ -68,7 +68,7 @@ and admin_instr' =
   | Throwing of Tag.t * value stack
   | Label of int32 * instr list * code
   | Frame of int32 * frame * code
-  | Handle of int32 * catch list * code
+  | Handler of int32 * catch list * code
 
 type config =
 {
@@ -244,7 +244,7 @@ let rec step (c : config) : config =
         let n1 = Lib.List32.length ts1 in
         let n2 = Lib.List32.length ts2 in
         let args, vs' = take n1 vs e.at, drop n1 vs e.at in
-        vs', [Handle (n2, cs, (args, [Label (n2, [], ([], List.map plain es')) @@ e.at])) @@ e.at]
+        vs', [Handler (n2, cs, (args, [Label (n2, [], ([], List.map plain es')) @@ e.at])) @@ e.at]
 
       | Drop, v :: vs' ->
         vs', []
@@ -691,36 +691,36 @@ let rec step (c : config) : config =
       let c' = step {frame = frame'; code = code'; budget = c.budget - 1} in
       vs, [Frame (n, c'.frame, c'.code) @@ e.at]
 
-    | Handle (n, cs, (vs', [])), vs ->
+    | Handler (n, cs, (vs', [])), vs ->
       vs' @ vs, []
 
-    | Handle (n, cs, (vs', ({it = Trapping _ | Breaking _ | Returning _ | ReturningInvoke _; at} as e) :: es')), vs ->
+    | Handler (n, cs, (vs', ({it = Trapping _ | Breaking _ | Returning _ | ReturningInvoke _; at} as e) :: es')), vs ->
       vs, [e]
 
-    | Handle (n, {it = Catch (x1, x2); _} :: cs, (vs', {it = Throwing (a, vs0); at} :: es')), vs ->
+    | Handler (n, {it = Catch (x1, x2); _} :: cs, (vs', {it = Throwing (a, vs0); at} :: es')), vs ->
       if a == tag frame.inst x1 then
         vs0 @ vs, [Plain (Br x2) @@ e.at]
       else
-        vs, [Handle (n, cs, (vs', {it = Throwing (a, vs0); at} :: es')) @@ e.at]
+        vs, [Handler (n, cs, (vs', {it = Throwing (a, vs0); at} :: es')) @@ e.at]
 
-    | Handle (n, {it = CatchRef (x1, x2); _} :: cs, (vs', {it = Throwing (a, vs0); at} :: es')), vs ->
+    | Handler (n, {it = CatchRef (x1, x2); _} :: cs, (vs', {it = Throwing (a, vs0); at} :: es')), vs ->
       if a == tag frame.inst x1 then
         Ref (ExnRef (a, vs0)) :: vs0 @ vs, [Plain (Br x2) @@ e.at]
       else
-        vs, [Handle (n, cs, (vs', {it = Throwing (a, vs0); at} :: es')) @@ e.at]
+        vs, [Handler (n, cs, (vs', {it = Throwing (a, vs0); at} :: es')) @@ e.at]
 
-    | Handle (n, {it = CatchAll x; _} :: cs, (vs', {it = Throwing (a, vs0); at} :: es')), vs ->
+    | Handler (n, {it = CatchAll x; _} :: cs, (vs', {it = Throwing (a, vs0); at} :: es')), vs ->
       vs, [Plain (Br x) @@ e.at]
 
-    | Handle (n, {it = CatchAllRef x; _} :: cs, (vs', {it = Throwing (a, vs0); at} :: es')), vs ->
+    | Handler (n, {it = CatchAllRef x; _} :: cs, (vs', {it = Throwing (a, vs0); at} :: es')), vs ->
       Ref (ExnRef (a, vs0)) :: vs, [Plain (Br x) @@ e.at]
 
-    | Handle (n, [], (vs', {it = Throwing (a, vs0); at} :: es')), vs ->
+    | Handler (n, [], (vs', {it = Throwing (a, vs0); at} :: es')), vs ->
       vs, [Throwing (a, vs0) @@ at]
 
-    | Handle (n, cs, code'), vs ->
+    | Handler (n, cs, code'), vs ->
       let c' = step {c with code = code'} in
-      vs, [Handle (n, cs, c'.code) @@ e.at]
+      vs, [Handler (n, cs, c'.code) @@ e.at]
 
     | Invoke func, vs when c.budget = 0 ->
       Exhaustion.error e.at "call stack exhausted"

interpreter/script/run.ml

@@ -409,6 +409,7 @@ let assert_ref_pat r p =
   match r, p with
   | r, RefPat r' -> r = r'.it
   | Instance.FuncRef _, RefTypePat Types.FuncRefType
+  | Values.ExnRef _, RefTypePat Types.ExnRefType
   | ExternRef _, RefTypePat Types.ExternRefType -> true
   | _ -> false
 

interpreter/text/lexer.mll

@@ -285,6 +285,7 @@ rule token = parse
 
       | "ref.null" -> REF_NULL
       | "ref.func" -> REF_FUNC
+      | "ref.exn" -> REF_EXN
       | "ref.extern" -> REF_EXTERN
       | "ref.is_null" -> REF_IS_NULL
 

interpreter/text/parser.mly

@@ -224,7 +224,7 @@ let inline_type_explicit (c : context) x ft at =
 %token<string> OFFSET_EQ_NAT ALIGN_EQ_NAT
 %token<string Source.phrase -> Ast.instr' * Values.num> CONST
 %token<Ast.instr'> UNARY BINARY TEST COMPARE CONVERT
-%token REF_NULL REF_FUNC REF_EXTERN REF_IS_NULL
+%token REF_NULL REF_FUNC REF_EXN REF_EXTERN REF_IS_NULL
 %token<int option -> Memory.offset -> Ast.instr'> VEC_LOAD VEC_STORE
 %token<int option -> Memory.offset -> int -> Ast.instr'> VEC_LOAD_LANE VEC_STORE_LANE
 %token<V128.shape -> string Source.phrase list -> Source.region -> Ast.instr' * Values.vec> VEC_CONST
@@ -1260,6 +1260,7 @@ result :
   | LPAR CONST NAN RPAR { NumResult (NanPat (nanop $2 ($3 @@ ati 3))) @@ at () }
   | literal_ref { RefResult (RefPat ($1 @@ at ())) @@ at () }
   | LPAR REF_FUNC RPAR { RefResult (RefTypePat FuncRefType) @@ at () }
+/*| LPAR REF_EXN RPAR { RefResult (RefTypePat ExnRefType) @@ at () }*/
   | LPAR REF_EXTERN RPAR { RefResult (RefTypePat ExternRefType) @@ at () }
   | LPAR VEC_CONST VEC_SHAPE numpat_list RPAR {
     if V128.num_lanes $3 <> List.length $4 then

test/core/ref_null.wast

@@ -1,10 +1,13 @@
 (module
   (func (export "externref") (result externref) (ref.null extern))
+  (func (export "exnref") (result exnref) (ref.null exn))
   (func (export "funcref") (result funcref) (ref.null func))
 
   (global externref (ref.null extern))
+  (global exnref (ref.null exn))
   (global funcref (ref.null func))
 )
 
 (assert_return (invoke "externref") (ref.null extern))
+(assert_return (invoke "exnref") (ref.null exn))
 (assert_return (invoke "funcref") (ref.null func))