WASI runtime

Author: vouillon

compiler/bin-wasm_of_ocaml/cmd_arg.ml

@@ -46,6 +46,8 @@ let normalize_effects (effects : [ `Disabled | `Cps | `Jspi ] option) common :
         [--effects cps] *)
       if List.mem ~eq:String.equal "effects" common.Jsoo_cmdline.Arg.optim.enable
       then `Cps
+      else if List.mem ~eq:String.equal "wasi" common.Jsoo_cmdline.Arg.optim.enable
+      then `Disabled
       else `Jspi
   | Some ((`Disabled | `Cps | `Jspi) as e) -> e
 

compiler/bin-wasm_of_ocaml/compile.ml

@@ -81,9 +81,11 @@ let preprocessor_variables () =
   [ ( "effects"
     , Wat_preprocess.String
         (match Config.effects () with
-        | `Disabled | `Jspi -> "jspi"
+        | `Disabled -> "disabled"
+        | `Jspi -> "jspi"
         | `Cps -> "cps"
         | `Double_translation -> assert false) )
+  ; "wasi", Wat_preprocess.Bool (Config.Flag.wasi ())
   ]
 
 let with_runtime_files ~runtime_wasm_files f =
@@ -115,21 +117,26 @@ let build_runtime ~runtime_file =
             ; file = module_name ^ ".wat"
             ; source = Contents contents
             })
-          Runtime_files.wat_files
+          (if Config.Flag.wasi ()
+           then ("libc", Runtime_files.wasi_libc) :: Runtime_files.wat_files
+           else Runtime_files.wat_files)
       in
       Runtime.build
         ~link_options:[ "-g" ]
         ~opt_options:[ "-g"; "-O2" ]
         ~variables
         ~allowed_imports:
           (Some
-             [ "bindings"
-             ; "Math"
-             ; "js"
-             ; "wasm:js-string"
-             ; "wasm:text-encoder"
-             ; "wasm:text-decoder"
-             ])
+             (if Config.Flag.wasi ()
+              then [ "wasi_snapshot_preview1"; "OCaml" ]
+              else
+                [ "bindings"
+                ; "Math"
+                ; "js"
+                ; "wasm:js-string"
+                ; "wasm:text-encoder"
+                ; "wasm:text-decoder"
+                ]))
         ~inputs
         ~output_file:runtime_file
 
@@ -185,7 +192,10 @@ let link_and_optimize
   let t = Timer.make ~get_time:Unix.time () in
   let primitives =
     Binaryen.dead_code_elimination
-      ~dependencies:Runtime_files.dependencies
+      ~dependencies:
+        (if Config.Flag.wasi ()
+         then Runtime_files.wasi_dependencies
+         else Runtime_files.dependencies)
       ~opt_input_sourcemap:opt_temp_sourcemap
       ~opt_output_sourcemap:opt_temp_sourcemap'
       ~input_file:temp_file
@@ -302,7 +312,13 @@ let build_js_runtime ~primitives ?runtime_arguments () =
     | _ -> assert false
   in
   let init_fun =
-    match Parse_js.parse (Parse_js.Lexer.of_string Runtime_files.js_runtime) with
+    match
+      Parse_js.parse
+        (Parse_js.Lexer.of_string
+           (if Config.Flag.wasi ()
+            then Runtime_files.js_wasi_launcher
+            else Runtime_files.js_launcher))
+    with
     | [ (Expression_statement f, _) ] -> f
     | _ -> assert false
   in
@@ -600,9 +616,12 @@ let run
          if binaryen_times ()
          then Format.eprintf " link_and_optimize: %a@." Timer.print t2;
          let wasm_name =
-           Printf.sprintf
-             "code-%s"
-             (String.sub (Digest.to_hex (Digest.file tmp_wasm_file)) ~pos:0 ~len:20)
+           if Config.Flag.wasi ()
+           then "code"
+           else
+             Printf.sprintf
+               "code-%s"
+               (String.sub (Digest.to_hex (Digest.file tmp_wasm_file)) ~pos:0 ~len:20)
          in
          let tmp_wasm_file' = Filename.concat tmp_dir (wasm_name ^ ".wasm") in
          Sys.rename tmp_wasm_file tmp_wasm_file';

compiler/bin-wasm_of_ocaml/dune

@@ -28,6 +28,9 @@
   gen/gen.exe
   ../../runtime/wasm/runtime.js
   ../../runtime/wasm/deps.json
+  ../../runtime/wasm/runtime-wasi.js
+  ../../runtime/wasm/deps-wasi.json
+  ../../runtime/wasm/libc.wasm
   (glob_files ../../runtime/wasm/*.wat)
   (glob_files ../../runtime/wasm/runtime-*.wasm))
  (action

compiler/bin-wasm_of_ocaml/gen/gen.ml

@@ -77,13 +77,26 @@ let check_js_file fname =
 
 let default_flags = []
 
-let interesting_runtimes = [ [ "effects", `S "jspi" ]; [ "effects", `S "cps" ] ]
+let interesting_runtimes =
+  [ [ "effects", `S "jspi"; "wasi", `B false ]
+  ; [ "effects", `S "cps"; "wasi", `B false ]
+  ; [ "effects", `S "disabled"; "wasi", `B true ]
+  ; [ "effects", `S "cps"; "wasi", `B true ]
+  ]
+
+let defaults = [ "effects", "disabled" ]
 
 let name_runtime standard l =
   let flags =
     List.filter_map l ~f:(fun (k, v) ->
         match v with
-        | `S s -> Some s
+        | `S s ->
+            if
+              List.exists
+                ~f:(fun (k', s') -> String.equal k k' && String.equal s s')
+                defaults
+            then None
+            else Some s
         | `B b -> if b then Some k else None)
   in
   String.concat ~sep:"-" ("runtime" :: (if standard then [ "standard" ] else flags))
@@ -110,25 +123,31 @@ let print_flags f flags =
 
 let () =
   let () = set_binary_mode_out stdout true in
-  let js_runtime, deps, wat_files, runtimes =
+  let js_launcher, deps, js_wasi_launcher, wasi_deps, wasi_libc, wat_files, runtimes =
     match Array.to_list Sys.argv with
-    | _ :: js_runtime :: deps :: rest ->
-        assert (Filename.check_suffix js_runtime ".js");
+    | _ :: js_launcher :: deps :: js_wasi_launcher :: wasi_deps :: wasi_libc :: rest ->
+        assert (Filename.check_suffix js_launcher ".js");
+        assert (Filename.check_suffix js_wasi_launcher ".js");
         assert (Filename.check_suffix deps ".json");
+        assert (Filename.check_suffix wasi_deps ".json");
         let wat_files, rest =
           List.partition rest ~f:(fun f -> Filename.check_suffix f ".wat")
         in
         let wasm_files, rest =
           List.partition rest ~f:(fun f -> Filename.check_suffix f ".wasm")
         in
         assert (List.is_empty rest);
-        js_runtime, deps, wat_files, wasm_files
+        js_launcher, deps, js_wasi_launcher, wasi_deps, wasi_libc, wat_files, wasm_files
     | _ -> assert false
   in
-  check_js_file js_runtime;
+  check_js_file js_launcher;
+  check_js_file js_wasi_launcher;
   Format.printf "open Wasm_of_ocaml_compiler@.";
-  Format.printf "let js_runtime = {|\n%s\n|}@." (Fs.read_file js_runtime);
+  Format.printf "let js_launcher = {|\n%s\n|}@." (Fs.read_file js_launcher);
   Format.printf "let dependencies = {|\n%s\n|}@." (Fs.read_file deps);
+  Format.printf "let js_wasi_launcher = {|\n%s\n|}@." (Fs.read_file js_wasi_launcher);
+  Format.printf "let wasi_dependencies = {|\n%s\n|}@." (Fs.read_file wasi_deps);
+  Format.printf "let wasi_libc = %S@." (Fs.read_file wasi_libc);
   Format.printf
     "let wat_files = [%a]@."
     (Format.pp_print_list (fun f file ->

compiler/lib-wasm/binaryen.ml

@@ -38,6 +38,7 @@ let common_options () =
     ; "--enable-bulk-memory"
     ; "--enable-nontrapping-float-to-int"
     ; "--enable-strings"
+    ; "--enable-multimemory" (* To keep wasm-merge happy *)
     ]
   in
   let l = if Config.Flag.pretty () then "-g" :: l else l in

compiler/lib-wasm/gc_target.ml

@@ -1296,7 +1296,12 @@ module Math = struct
     { W.params = List.init ~len:n ~f:(fun _ : W.value_type -> F64); result = [ F64 ] }
 
   let unary name x =
-    let* f = register_import ~import_module:"Math" ~name (Fun (float_func_type 1)) in
+    let* f =
+      register_import
+        ~import_module:(if Config.Flag.wasi () then "env" else "Math")
+        ~name
+        (Fun (float_func_type 1))
+    in
     let* x = x in
     return (W.Call (f, [ x ]))
 
@@ -1339,7 +1344,12 @@ module Math = struct
   let log10 f = unary "log10" f
 
   let binary name x y =
-    let* f = register_import ~import_module:"Math" ~name (Fun (float_func_type 2)) in
+    let* f =
+      register_import
+        ~import_module:(if Config.Flag.wasi () then "env" else "Math")
+        ~name
+        (Fun (float_func_type 2))
+    in
     let* x = x in
     let* y = y in
     return (W.Call (f, [ x; y ]))
@@ -1682,21 +1692,34 @@ let handle_exceptions ~result_typ ~fall_through ~context body x exn_handler =
          x
          (block_expr
             { params = []; result = [ Type.value ] }
-            (let* exn =
-               block_expr
-                 { params = []; result = [ externref ] }
-                 (let* e =
-                    try_expr
-                      { params = []; result = [ externref ] }
-                      (body
-                         ~result_typ:[ externref ]
-                         ~fall_through:`Skip
-                         ~context:(`Skip :: `Skip :: `Catch :: context))
-                      [ ocaml_tag, 1, Type.value; js_tag, 0, externref ]
-                  in
-                  instr (W.Push e))
-             in
-             instr (W.CallInstr (f, [ exn ]))))
+            (if Config.Flag.wasi ()
+             then
+               let* e =
+                 try_expr
+                   { params = []; result = [ Type.value ] }
+                   (body
+                      ~result_typ:[ Type.value ]
+                      ~fall_through:`Skip
+                      ~context:(`Skip :: `Catch :: context))
+                   [ ocaml_tag, 0, Type.value ]
+               in
+               instr (W.Push e)
+             else
+               let* exn =
+                 block_expr
+                   { params = []; result = [ externref ] }
+                   (let* e =
+                      try_expr
+                        { params = []; result = [ externref ] }
+                        (body
+                           ~result_typ:[ externref ]
+                           ~fall_through:`Skip
+                           ~context:(`Skip :: `Skip :: `Catch :: context))
+                        [ ocaml_tag, 1, Type.value; js_tag, 0, externref ]
+                    in
+                    instr (W.Push e))
+               in
+               instr (W.CallInstr (f, [ exn ]))))
      in
      let* () = no_event in
      exn_handler ~result_typ ~fall_through ~context)

compiler/lib-wasm/generate.ml

@@ -226,7 +226,7 @@ module Generate (Target : Target_sig.S) = struct
         (if negate then Arith.( <> ) else Arith.( = ))
           Arith.(transl_prim_arg ctx ~typ:(Int Unnormalized) x lsl const 1l)
           Arith.(transl_prim_arg ctx ~typ:(Int Unnormalized) y lsl const 1l)
-    | Top, Top ->
+    | Top, Top when not (Config.Flag.wasi ()) ->
         Value.js_eqeqeq
           ~negate
           (transl_prim_arg ctx ~typ:Top x)
@@ -236,7 +236,9 @@ module Generate (Target : Target_sig.S) = struct
         (if negate then Value.phys_neq else Value.phys_eq)
           (transl_prim_arg ctx ~typ:Top x)
           (transl_prim_arg ctx ~typ:Top y)
-    | (Int _ | Number _ | Tuple _), _ | _, (Int _ | Number _ | Tuple _) ->
+    | (Int _ | Number _ | Tuple _), _
+    | _, (Int _ | Number _ | Tuple _)
+    | Top, Top (* when wasi is enabled *) ->
         (* Only Top may contain JavaScript values *)
         (if negate then Value.phys_neq else Value.phys_eq)
           (transl_prim_arg ctx ~typ:Top x)

compiler/lib/config.ml

@@ -106,6 +106,8 @@ module Flag = struct
   let es6 = o ~name:"es6" ~default:false
 
   let load_shapes_auto = o ~name:"load-shapes-auto" ~default:false
+
+  let wasi = o ~name:"wasi" ~default:false
 end
 
 module Param = struct

compiler/lib/config.mli

@@ -76,6 +76,8 @@ module Flag : sig
 
   val load_shapes_auto : unit -> bool
 
+  val wasi : unit -> bool
+
   val enable : string -> unit
 
   val disable : string -> unit

compiler/tests-jsoo/dune

@@ -11,6 +11,8 @@
  (enabled_if
   (>= %{ocaml_version} 4.14))
  (inline_tests
+  (deps
+   (sandbox preserve_file_kind))
   (modes js wasm best))
  (preprocess
   (pps ppx_expect)))
@@ -22,6 +24,8 @@
  (enabled_if
   (>= %{ocaml_version} 5.1.1))
  (inline_tests
+  (deps
+   (sandbox preserve_file_kind))
   (modes js wasm best))
  (preprocess
   (pps ppx_expect)))
@@ -33,6 +37,22 @@
  (enabled_if
   (>= %{ocaml_version} 5.1.1))
  (inline_tests
+  (deps
+   (sandbox preserve_file_kind))
+  (modes js wasm best))
+ (preprocess
+  (pps ppx_expect)))
+
+(library
+ (name jsoo_testsuite_perms)
+ (modules test_unix_perms)
+ (libraries unix)
+ ;; WASI has no notion of file permissions (it uses capabilities instead)
+ (enabled_if
+  (<> %{profile} wasi))
+ (inline_tests
+  (deps
+   (sandbox preserve_file_kind))
   (modes js wasm best))
  (preprocess
   (pps ppx_expect)))
@@ -48,13 +68,16 @@
    test_bigarray
    test_marshal_compressed
    test_parsing
+   test_unix_perms
    calc_parser
    calc_lexer))
  (libraries unix compiler-libs.common js_of_ocaml-compiler)
  (foreign_stubs
   (language c)
   (names bigarray_stubs jsoo_runtime_stubs))
  (inline_tests
+  (deps
+   (sandbox preserve_file_kind))
   (modes js wasm best))
  (preprocess
   (pps ppx_expect)))