[wasm] Add a debug option to keep wat files

Author: vouillon

compiler/bin-wasm_of_ocaml/build_runtime.ml

@@ -25,5 +25,5 @@ let info =
     ~description:"Wasm_of_ocaml is a compiler from OCaml bytecode to WebAssembly."
 
 let command =
-  let t = Cmdliner.Term.(const Compile.run $ Cmd_arg.options_runtime_only) in
+  let t = Cmdliner.Term.(const Compile.run $ Cmd_arg.options_runtime_only ()) in
   Cmdliner.Cmd.v info t

compiler/bin-wasm_of_ocaml/cmd_arg.ml

@@ -63,7 +63,7 @@ type t =
   ; effects : Config.effects_backend
   }
 
-let options =
+let options () =
   let runtime_files =
     let doc = "Link JavaScript and WebAssembly files [$(docv)]. " in
     Arg.(value & pos_left ~rev:true 0 string [] & info [] ~docv:"RUNTIME_FILES" ~doc)
@@ -189,7 +189,7 @@ let options =
   in
   Term.ret t
 
-let options_runtime_only =
+let options_runtime_only () =
   let runtime_files =
     let doc = "Link JavaScript and WebAssembly files [$(docv)]. " in
     Arg.(value & pos_all string [] & info [] ~docv:"RUNTIME_FILES" ~doc)

compiler/bin-wasm_of_ocaml/cmd_arg.mli

@@ -34,6 +34,6 @@ type t =
   ; effects : Config.effects_backend
   }
 
-val options : t Cmdliner.Term.t
+val options : unit -> t Cmdliner.Term.t
 
-val options_runtime_only : t Cmdliner.Term.t
+val options_runtime_only : unit -> t Cmdliner.Term.t

compiler/bin-wasm_of_ocaml/compile.ml

@@ -24,6 +24,8 @@ let times = Debug.find "times"
 
 let debug_mem = Debug.find "mem"
 
+let debug_wat = Debug.find "wat"
+
 let () = Sys.catch_break true
 
 let update_sourcemap ~sourcemap_root ~sourcemap_don't_inline_content sourcemap_file =
@@ -425,7 +427,11 @@ let run
           else None)
        @@ fun opt_tmp_map_file ->
        let unit_data =
-         Fs.with_intermediate_file (Filename.temp_file unit_name ".wat")
+         (if debug_wat ()
+          then
+            fun f ->
+              f (Filename.concat (Filename.dirname output_file) (unit_name ^ ".wat"))
+          else Fs.with_intermediate_file (Filename.temp_file unit_name ".wat"))
          @@ fun wat_file ->
          let strings, fragments =
            output_gen wat_file (output code ~unit_name:(Some unit_name))
@@ -454,7 +460,9 @@ let run
              ic
          in
          if times () then Format.eprintf "  parsing: %a@." Timer.print t1;
-         Fs.with_intermediate_file (Filename.temp_file "code" ".wat")
+         (if debug_wat ()
+          then fun f -> f (Filename.chop_extension output_file ^ ".wat")
+          else Fs.with_intermediate_file (Filename.temp_file "code" ".wat"))
          @@ fun wat_file ->
          let dir = Filename.chop_extension output_file ^ ".assets" in
          Link.gen_dir dir
@@ -575,8 +583,10 @@ let info name =
     ~doc:"Wasm_of_ocaml compiler"
     ~description:"Wasm_of_ocaml is a compiler from OCaml bytecode to WebAssembly."
 
-let term = Cmdliner.Term.(const run $ Cmd_arg.options)
+let options = Cmd_arg.options ()
+
+let term = Cmdliner.Term.(const run $ options)
 
 let command =
-  let t = Cmdliner.Term.(const run $ Cmd_arg.options) in
+  let t = Cmdliner.Term.(const run $ options) in
   Cmdliner.Cmd.v (info "compile") t

compiler/bin-wasm_of_ocaml/link.ml

@@ -29,7 +29,7 @@ type t =
   ; enable_source_maps : bool
   }
 
-let options =
+let options () =
   let output_file =
     let doc = "Set output file name to [$(docv)]." in
     Arg.(required & opt (some string) None & info [ "o" ] ~docv:"FILE" ~doc)
@@ -91,6 +91,6 @@ let info =
       "wasm_of_ocaml-link links together several wasm_of_ocaml intermediate files to \
        produce either a library or some executable code."
 
-let command =
-  let t = Cmdliner.Term.(const f $ options) in
+let command () =
+  let t = Cmdliner.Term.(const f $ options ()) in
   Cmdliner.Cmd.v info t

compiler/bin-wasm_of_ocaml/link.mli

@@ -16,4 +16,4 @@
  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  *)
 
-val command : unit Cmdliner.Cmd.t
+val command : unit -> unit Cmdliner.Cmd.t

compiler/bin-wasm_of_ocaml/wasm_of_ocaml.ml

@@ -48,7 +48,7 @@ let () =
         (Cmdliner.Cmd.group
            ~default:Compile.term
            (Compile.info "wasm_of_ocaml")
-           [ Link.command
+           [ Link.command ()
            ; Build_runtime.command
            ; Compile.command
            ; Preprocess.command