Implemented EVM.ABI.encode_int*_parameter_as_uint256.

Author: artob

lib/Clar2EVM/compile.ml

@@ -240,9 +240,9 @@ and compile_expression env = function
   | FunctionCall ("get", [Identifier _; Identifier _]) ->  (* TODO *)
     [
       EVM.from_int 0x80;                 (* 128 bits *)
-      EVM.from_int 2; EVM.EXP; EVM.MUL;  (* equivalent to EVM.SHL *)
+      EVM.two; EVM.EXP; EVM.MUL;         (* equivalent to EVM.SHL *)
       EVM.from_int 0x80;                 (* 128 bits *)
-      EVM.from_int 2; EVM.EXP; EVM.SWAP 1; EVM.DIV;  (* equivalent to EVM.SWAP 1; EVM.SHR *)
+      EVM.two; EVM.EXP; EVM.SWAP 1; EVM.DIV;  (* equivalent to EVM.SWAP 1; EVM.SHR *)
     ]
 
   | FunctionCall ("hash160", [value]) ->
@@ -376,7 +376,7 @@ and compile_tuple_literal = function
 
 and compile_packed_word hi lo =
   (* [EVM.from_big_int hi; EVM.from_int 0x80; EVM.SHL; EVM.from_big_int lo; EVM.OR] *)
-  [EVM.from_big_int hi; EVM.from_int 0x80; EVM.from_int 2; EVM.EXP; EVM.MUL; EVM.from_big_int lo; EVM.OR]
+  [EVM.from_big_int hi; EVM.from_int 0x80; EVM.two; EVM.EXP; EVM.MUL; EVM.from_big_int lo; EVM.OR]
 
 and compile_param (_, type') =
   compile_type type'

lib/Clar2EVM/utility.ml

@@ -2,9 +2,19 @@
 
 let unreachable () = failwith "unreachable"
 
-let unimplemented what = failwith (Printf.sprintf "%s not implemented yet" what)
+let unimplemented what =
+  let message =
+    if what = "" then "not implemented yet"
+    else Printf.sprintf "%s not implemented yet" what
+  in
+  failwith message
 
-let unsupported what = failwith (Printf.sprintf "%s not supported" what)
+let unsupported what =
+  let message =
+    if what = "" then "not supported"
+    else Printf.sprintf "%s not supported" what
+  in
+  failwith message
 
 let rec last = function
   | [] -> None

lib/EVM/EVM.ml

@@ -1,5 +1,6 @@
 (* This is free and unencumbered software released into the public domain. *)
 
+#include "utility.ml"
 #include "opcodes.ml"
 #include "abi.ml"
 #include "construct.ml"

lib/EVM/EVM.mli

@@ -1,5 +1,6 @@
 (* This is free and unencumbered software released into the public domain. *)
 
+#include "utility.mli"
 #include "opcodes.ml"
 #include "abi.mli"
 #include "construct.mli"

lib/EVM/abi.ml

@@ -10,4 +10,23 @@ module ABI = struct
 
   and encode_function_signature signature =
     String.sub (keccak256 signature) 0 4
+
+  and encode_int_parameter_as_uint256 z =
+    encode_int64_parameter_as_uint256 (Int64.of_int z)
+
+  and encode_int32_parameter_as_uint256 z =
+    encode_int64_parameter_as_uint256 (Int64.of_int32 z)
+
+  and encode_int64_parameter_as_uint256 z =
+    let buffer = Buffer.create 32 in
+    Buffer.add_int64_be buffer 0L;
+    Buffer.add_int64_be buffer 0L;
+    Buffer.add_int64_be buffer 0L;
+    Buffer.add_int64_be buffer z;
+    Buffer.contents buffer
+
+  and encode_bigint_parameter_as_uint256 z =
+    match Big_int.int64_of_big_int_opt z with
+    | Some z -> encode_int64_parameter_as_uint256 z
+    | None -> unimplemented ""  (* TODO *)
 end

lib/EVM/abi.mli

@@ -3,4 +3,8 @@
 module ABI : sig
   val encode_function : string -> string list -> string
   val encode_function_signature : string -> string
+  val encode_int_parameter_as_uint256 : int -> string
+  val encode_int32_parameter_as_uint256 : int32 -> string
+  val encode_int64_parameter_as_uint256 : int64 -> string
+  val encode_bigint_parameter_as_uint256 : Big_int.big_int -> string
 end

lib/EVM/construct.ml

@@ -6,13 +6,15 @@ let from_string s =
 let rec from_big_int z =
   match Big_int.int_of_big_int_opt z with
   | Some z -> from_int z
-  | None -> failwith "not implemented yet"  (* TODO *)
+  | None -> PUSH (32, ABI.encode_bigint_parameter_as_uint256 z)
 
 and from_int z =
-  if z < 0 then failwith "not implemented yet"  (* TODO *)
+  if z < 0 then unimplemented "encoding of negative integers"  (* FIXME *)
   else if z <= 0xFF then PUSH (1, Char.chr z |> String.make 1)
-  else failwith "not implemented yet"  (* TODO *)
+  else PUSH (32, ABI.encode_int_parameter_as_uint256 z)
 
 let zero = from_int 0
 
 let one = from_int 1
+
+let two = from_int 2

lib/EVM/construct.mli

@@ -4,6 +4,8 @@ val zero : opcode
 
 val one : opcode
 
+val two : opcode
+
 val from_big_int : Big_int.big_int -> opcode
 
 val from_int : int -> opcode

lib/EVM/dune

@@ -16,5 +16,7 @@
   metrics.mli
   opcodes.ml
   print.ml
-  print.mli)
+  print.mli
+  utility.ml
+  utility.mli)
  (libraries cryptokit num))

lib/EVM/encode.ml

@@ -100,7 +100,7 @@ and encode_opcode = function
   | MSIZE -> 0x59
   | GAS -> 0x5A
   | JUMPDEST -> 0x5B
-  | PUSH (0, _) -> failwith "unreachable"
+  | PUSH (0, _) -> unreachable ()
   | PUSH (n, _) -> 0x60 + n - 1
   | DUP n -> 0x80 + n - 1
   | SWAP n -> 0x90 + n - 1