Change to_bits to return string

Author: ngzhian

interpreter/binary/encode.ml

@@ -62,6 +62,7 @@ let encode m =
     let vs32 i = vs64 (Int64.of_int32 i)
     let f32 x = u32 (F32.to_bits x)
     let f64 x = u64 (F64.to_bits x)
+    let v128 v = String.iter (put s) (V128.to_bits v)
 
     let len i =
       if Int32.to_int (Int32.of_int i) <> i then
@@ -225,7 +226,7 @@ let encode m =
       | Const {it = I64 c; _} -> op 0x42; vs64 c
       | Const {it = F32 c; _} -> op 0x43; f32 c
       | Const {it = F64 c; _} -> op 0x44; f64 c
-      | Const {it = V128 c; _} -> simd_op 0x02; Bytes.iter (put s) (V128.to_bits c)
+      | Const {it = V128 c; _} -> simd_op 0x02; v128 c
 
       | Test (I32 I32Op.Eqz) -> op 0x45
       | Test (I64 I64Op.Eqz) -> op 0x50

interpreter/exec/simd.ml

@@ -20,6 +20,8 @@ sig
   val to_string : t -> string
   val bytewidth : int
   val of_strings : shape -> string list -> t
+  val of_bits : string -> t
+  val to_bits : t -> string
 end
 
 module type S =
@@ -33,14 +35,14 @@ sig
   val of_strings : shape -> string list -> t
 end
 
-module Make (Rep : RepType) : S with type bits = Rep.t =
+module Make (Rep : RepType) : S with type bits = string =
 struct
   type t = Rep.t
-  type bits = Rep.t
+  type bits = string
 
   let default = Rep.make Rep.bytewidth (chr 0)
   let to_string = Rep.to_string (* FIXME very very wrong *)
-  let to_bits x = x
-  let of_bits x = x
+  let of_bits = Rep.of_bits
+  let to_bits = Rep.to_bits
   let of_strings = Rep.of_strings
 end

interpreter/exec/v128.ml

@@ -2,6 +2,8 @@ include Simd.Make
   (struct
     include Bytes
     let bytewidth = 16
+    let of_bits = Bytes.of_string
+    let to_bits = Bytes.to_string
 
     let of_strings shape ss =
       if List.length ss <> Simd.lanes shape then raise (Invalid_argument "wrong length");