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(* Wasm_of_ocaml compiler
* http://www.ocsigen.org/js_of_ocaml/
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, with linking exception;
* either version 2.1 of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*)
open! Stdlib
open Wasm_ast
let assign_names ?(reversed = true) (f : Code.Var.t -> string option) names =
let used = ref StringSet.empty in
let counts = String.Hashtbl.create 101 in
let rec find_available_name used name =
let i =
try String.Hashtbl.find counts name
with Not_found ->
let i = ref 0 in
String.Hashtbl.replace counts name i;
i
in
incr i;
let nm = Printf.sprintf "%s$%d" name !i in
if StringSet.mem nm used then find_available_name used name else nm
in
let names = if reversed then List.rev names else names in
let names =
List.map
~f:(fun x ->
match f x with
| None -> x, None
| Some nm ->
let nm =
if StringSet.mem nm !used then find_available_name !used nm else nm
in
used := StringSet.add nm !used;
x, Some nm)
names
in
let printer = Var_printer.create Var_printer.Alphabet.javascript in
let i = ref 0 in
let rec first_available_name () =
let nm = Var_printer.to_string printer !i in
incr i;
if StringSet.mem nm !used then first_available_name () else nm
in
let tbl = Code.Var.Hashtbl.create 16 in
List.iter
~f:(fun (x, nm) ->
Code.Var.Hashtbl.add
tbl
x
(match nm with
| Some nm -> nm
| None -> first_available_name ()))
names;
tbl
type st =
{ type_names : string Code.Var.Hashtbl.t
; func_names : string Code.Var.Hashtbl.t
; global_names : string Code.Var.Hashtbl.t
; data_names : string Code.Var.Hashtbl.t
; tag_names : string Code.Var.Hashtbl.t
; local_names : string Code.Var.Hashtbl.t
}
let build_name_tables fields =
let type_names = ref [] in
let func_names = ref [] in
let data_names = ref [] in
let global_names = ref [] in
let tag_names = ref [] in
let push l v = l := v :: !l in
List.iter
~f:(fun field ->
match field with
| Function { name; _ } -> push func_names name
| Type l -> List.iter ~f:(fun { name; _ } -> push type_names name) l
| Data { name; _ } -> push data_names name
| Global { name; _ } -> push global_names name
| Tag { name; _ } -> push tag_names name
| Import { name; desc; _ } -> (
match desc with
| Fun _ -> push func_names name
| Global _ -> push global_names name
| Tag _ -> push tag_names name))
fields;
let index = Code.Var.get_name in
{ type_names = assign_names index !type_names
; func_names = assign_names index !func_names
; global_names = assign_names index !global_names
; data_names = assign_names index !data_names
; tag_names = assign_names index !tag_names
; local_names = Code.Var.Hashtbl.create 1
}
type sexp =
| Atom of string
| List of sexp list
| Comment of string
(** Line comment. String [s] is rendered as [;;s], on its own line,
without space after the double semicolon. *)
let rec format_sexp f s =
match s with
| Atom s -> Format.pp_print_string f s
| List l ->
let has_comment =
List.exists l ~f:(function
| Comment _ -> true
| _ -> false)
in
if has_comment
then (* Ensure comments are on their own line *)
Format.pp_open_vbox f 2
else Format.pp_open_box f 2;
Format.pp_print_string f "(";
Format.pp_print_list
~pp_sep:(fun f () -> Format.pp_print_space f ())
format_sexp
f
l;
if
has_comment
&&
match List.last l with
| Some (Comment _) -> true
| Some _ | None -> false
then
(* Make sure there is a newline when a comment is at the very end. *)
Format.pp_print_space f ();
Format.pp_print_string f ")";
Format.pp_close_box f ()
| Comment s ->
Format.pp_print_string f ";;";
Format.pp_print_string f s
let escape_string s =
let b = Buffer.create (String.length s + 2) in
for i = 0 to String.length s - 1 do
let c = s.[i] in
if Char.(c >= ' ' && c <= '~' && c <> '"' && c <> '\\')
then Buffer.add_char b c
else Printf.bprintf b "\\%02x" (Char.code c)
done;
Buffer.contents b
let index tbl x = Atom ("$" ^ Code.Var.Hashtbl.find tbl x)
let heap_type st (ty : heap_type) =
match ty with
| Func -> Atom "func"
| Extern -> Atom "extern"
| Any -> Atom "any"
| Eq -> Atom "eq"
| Struct -> Atom "struct"
| Array -> Atom "array"
| I31 -> Atom "i31"
| None_ -> Atom "none"
| Type t -> index st.type_names t
let ref_type st { nullable; typ } =
let r = [ heap_type st typ ] in
List (Atom "ref" :: (if nullable then Atom "null" :: r else r))
let value_type st (t : value_type) =
match t with
| I32 -> Atom "i32"
| I64 -> Atom "i64"
| F32 -> Atom "f32"
| F64 -> Atom "f64"
| Ref ty -> ref_type st ty
let packed_type t =
match t with
| I8 -> Atom "i8"
| I16 -> Atom "i16"
let list ?(always = false) name f l =
if (not always) && List.is_empty l then [] else [ List (Atom name :: f l) ]
let value_type_list st name tl =
list name (fun tl -> List.map ~f:(fun t -> value_type st t) tl) tl
let func_type st ?param_names { params; result } =
(match param_names with
| None -> value_type_list st "param" params
| Some names ->
List.map2
~f:(fun i typ -> List [ Atom "param"; index st.local_names i; value_type st typ ])
names
params)
@ value_type_list st "result" result
let storage_type st typ =
match typ with
| Value typ -> value_type st typ
| Packed typ -> packed_type typ
let mut_type f { mut; typ } = if mut then List [ Atom "mut"; f typ ] else f typ
let field_type st typ = mut_type (fun t -> storage_type st t) typ
let global_type st typ = mut_type (fun t -> value_type st t) typ
let str_type st typ =
match typ with
| Func ty -> List (Atom "func" :: func_type st ty)
| Struct l ->
List
(Atom "struct" :: List.map ~f:(fun f -> List [ Atom "field"; field_type st f ]) l)
| Array ty -> List [ Atom "array"; field_type st ty ]
let block_type = func_type
let quoted_name name = Atom ("\"" ^ escape_string name ^ "\"")
let export name =
match name with
| None -> []
| Some name -> [ List [ Atom "export"; quoted_name name ] ]
let type_prefix op nm =
(match op with
| I32 _ -> "i32."
| I64 _ -> "i64."
| F32 _ -> "f32."
| F64 _ -> "f64.")
^ nm
let signage op (s : Wasm_ast.signage) =
op
^
match s with
| S -> "_s"
| U -> "_u"
let int_un_op sz op =
match op with
| Clz -> "clz"
| Ctz -> "ctz"
| Popcnt -> "popcnt"
| Eqz -> "eqz"
| TruncSatF64 s -> signage "trunc_sat_f64" s
| ReinterpretF -> "reinterpret_f" ^ sz
let int_bin_op _ (op : int_bin_op) =
match op with
| Add -> "add"
| Sub -> "sub"
| Mul -> "mul"
| Div s -> signage "div" s
| Rem s -> signage "rem" s
| And -> "and"
| Or -> "or"
| Xor -> "xor"
| Shl -> "shl"
| Shr s -> signage "shr" s
| Rotl -> "rotl"
| Rotr -> "rotr"
| Eq -> "eq"
| Ne -> "ne"
| Lt s -> signage "lt" s
| Gt s -> signage "gt" s
| Le s -> signage "le" s
| Ge s -> signage "ge" s
let float_un_op sz op =
match op with
| Neg -> "neg"
| Abs -> "abs"
| Ceil -> "ceil"
| Floor -> "floor"
| Trunc -> "trunc"
| Nearest -> "nearest"
| Sqrt -> "sqrt"
| Convert (`I32, s) -> signage "convert_i32" s
| Convert (`I64, s) -> signage "convert_i64" s
| ReinterpretI -> "reinterpret_i" ^ sz
let float_bin_op _ op =
match op with
| Add -> "add"
| Sub -> "sub"
| Mul -> "mul"
| Div -> "div"
| Min -> "min"
| Max -> "max"
| CopySign -> "copysign"
| Eq -> "eq"
| Ne -> "ne"
| Lt -> "lt"
| Gt -> "gt"
| Le -> "le"
| Ge -> "ge"
let select i32 i64 f32 f64 op =
match op with
| I32 x -> i32 "32" x
| I64 x -> i64 "64" x
| F32 x -> f32 "32" x
| F64 x -> f64 "64" x
type ctx = { mutable function_refs : Code.Var.Set.t }
let reference_function ctx f = ctx.function_refs <- Code.Var.Set.add f ctx.function_refs
let remove_nops l =
List.filter
~f:(function
| Nop -> false
| _ -> true)
l
let float64 _ f =
match classify_float f with
| FP_normal | FP_subnormal | FP_zero -> Printf.sprintf "%h" f
| FP_nan ->
Printf.sprintf
"nan:0x%Lx"
Int64.(logand (bits_of_float f) (of_int ((1 lsl 52) - 1)))
| FP_infinite -> if Float.(f > 0.) then "inf" else "-inf"
let float32 _ f =
match classify_float f with
| FP_normal | FP_subnormal | FP_zero -> Printf.sprintf "%h" f
| FP_nan ->
Printf.sprintf
"nan:0x%lx"
Int32.(logand (bits_of_float f) (of_int ((1 lsl 23) - 1)))
| FP_infinite -> if Float.(f > 0.) then "inf" else "-inf"
let expression_or_instructions ctx st in_function =
let rec expression e =
match e with
| Const op ->
[ List
[ Atom (type_prefix op "const")
; Atom
(select
(fun _ i -> Int32.to_string i)
(fun _ i -> Int64.to_string i)
float32
float64
op)
]
]
| UnOp (op, e') ->
[ List
(Atom (type_prefix op (select int_un_op int_un_op float_un_op float_un_op op))
:: expression e')
]
| BinOp (op, e1, e2) ->
[ List
(Atom
(type_prefix
op
(select int_bin_op int_bin_op float_bin_op float_bin_op op))
:: (expression e1 @ expression e2))
]
| I32WrapI64 e -> [ List (Atom "i32.wrap_i64" :: expression e) ]
| I64ExtendI32 (s, e) -> [ List (Atom (signage "i64.extend_i32" s) :: expression e) ]
| F32DemoteF64 e -> [ List (Atom "f32.demote_f64" :: expression e) ]
| F64PromoteF32 e -> [ List (Atom "f64.promote_f32" :: expression e) ]
| LocalGet i -> [ List [ Atom "local.get"; index st.local_names i ] ]
| LocalTee (i, e') ->
[ List (Atom "local.tee" :: index st.local_names i :: expression e') ]
| GlobalGet nm -> [ List [ Atom "global.get"; index st.global_names nm ] ]
| BlockExpr (ty, l) -> [ List (Atom "block" :: (block_type st ty @ instructions l)) ]
| Call (f, l) ->
[ List
(Atom "call"
:: index st.func_names f
:: List.concat (List.map ~f:expression l))
]
| Seq (l, e) -> instructions l @ expression e
| Pop _ -> []
| RefFunc symb ->
if in_function then reference_function ctx symb;
[ List [ Atom "ref.func"; index st.func_names symb ] ]
| Call_ref (f, e, l) ->
[ List
(Atom "call_ref"
:: index st.type_names f
:: List.concat (List.map ~f:expression (l @ [ e ])))
]
| RefI31 e -> [ List (Atom "ref.i31" :: expression e) ]
| I31Get (s, e) -> [ List (Atom (signage "i31.get" s) :: expression e) ]
| ArrayNew (typ, e, e') ->
[ List
(Atom "array.new" :: index st.type_names typ :: (expression e @ expression e'))
]
| ArrayNewFixed (typ, l) ->
[ List
(Atom "array.new_fixed"
:: index st.type_names typ
:: Atom (string_of_int (List.length l))
:: List.concat (List.map ~f:expression l))
]
| ArrayNewData (typ, data, e, e') ->
[ List
(Atom "array.new_data"
:: index st.type_names typ
:: index st.data_names data
:: (expression e @ expression e'))
]
| ArrayGet (None, typ, e, e') ->
[ List
(Atom "array.get" :: index st.type_names typ :: (expression e @ expression e'))
]
| ArrayGet (Some s, typ, e, e') ->
[ List
(Atom (signage "array.get" s)
:: index st.type_names typ
:: (expression e @ expression e'))
]
| ArrayLen e -> [ List (Atom "array.len" :: expression e) ]
| StructNew (typ, l) ->
[ List
(Atom "struct.new"
:: index st.type_names typ
:: List.concat (List.map ~f:expression l))
]
| StructGet (None, typ, i, e) ->
[ List
(Atom "struct.get"
:: index st.type_names typ
:: Atom (string_of_int i)
:: expression e)
]
| StructGet (Some s, typ, i, e) ->
[ List
(Atom (signage "struct.get" s)
:: index st.type_names typ
:: Atom (string_of_int i)
:: expression e)
]
| RefCast (ty, e) -> [ List (Atom "ref.cast" :: ref_type st ty :: expression e) ]
| RefTest (ty, e) -> [ List (Atom "ref.test" :: ref_type st ty :: expression e) ]
| RefEq (e, e') -> [ List (Atom "ref.eq" :: (expression e @ expression e')) ]
| RefNull ty -> [ List [ Atom "ref.null"; heap_type st ty ] ]
| Br_on_cast (i, ty, ty', e) ->
[ List
(Atom "br_on_cast"
:: Atom (string_of_int i)
:: ref_type st ty
:: ref_type st ty'
:: expression e)
]
| Br_on_cast_fail (i, ty, ty', e) ->
[ List
(Atom "br_on_cast_fail"
:: Atom (string_of_int i)
:: ref_type st ty
:: ref_type st ty'
:: expression e)
]
| Br_on_null (i, e) ->
[ List (Atom "br_on_null" :: Atom (string_of_int i) :: expression e) ]
| IfExpr (ty, cond, ift, iff) ->
[ List
((Atom "if" :: block_type st { params = []; result = [ ty ] })
@ expression cond
@ [ List (Atom "then" :: expression ift) ]
@ [ List (Atom "else" :: expression iff) ])
]
| Try (ty, body, catches) ->
[ List
(Atom "try"
:: (block_type st ty
@ List (Atom "do" :: instructions body)
:: List.map
~f:(fun (tag, i, ty) ->
List
(Atom "catch"
:: index st.tag_names tag
:: (instruction (Wasm_ast.Event Code_generation.hidden_location)
@ instruction (Wasm_ast.Br (i + 1, Some (Pop ty))))))
catches))
]
| ExternConvertAny e' -> [ List (Atom "extern.convert_any" :: expression e') ]
| AnyConvertExtern e' -> [ List (Atom "any.convert_extern" :: expression e') ]
and instruction i =
match i with
| Drop e -> [ List (Atom "drop" :: expression e) ]
| LocalSet (i, Seq (l, e)) -> instructions (l @ [ LocalSet (i, e) ])
| LocalSet (i, e) ->
[ List (Atom "local.set" :: index st.local_names i :: expression e) ]
| GlobalSet (nm, e) ->
[ List (Atom "global.set" :: index st.global_names nm :: expression e) ]
| Loop (ty, l) -> [ List (Atom "loop" :: (block_type st ty @ instructions l)) ]
| Block (ty, l) -> [ List (Atom "block" :: (block_type st ty @ instructions l)) ]
| If (ty, e, l1, l2) ->
[ List
(Atom "if"
:: (block_type st ty
@ expression e
@ list ~always:true "then" instructions (remove_nops l1)
@ list "else" instructions (remove_nops l2)))
]
| Br_table (e, l, i) ->
[ List
(Atom "br_table"
:: (List.map ~f:(fun i -> Atom (string_of_int i)) (l @ [ i ]) @ expression e)
)
]
| Br (i, e) ->
[ List
(Atom "br"
:: Atom (string_of_int i)
::
(match e with
| None -> []
| Some e -> expression e))
]
| Br_if (i, e) -> [ List (Atom "br_if" :: Atom (string_of_int i) :: expression e) ]
| Return e ->
[ List
(Atom "return"
::
(match e with
| None -> []
| Some e -> expression e))
]
| Throw (tag, e) -> [ List (Atom "throw" :: index st.tag_names tag :: expression e) ]
| Rethrow i -> [ List [ Atom "rethrow"; Atom (string_of_int i) ] ]
| CallInstr (f, l) ->
[ List
(Atom "call"
:: index st.func_names f
:: List.concat (List.map ~f:expression l))
]
| Nop -> []
| Push e -> expression e
| ArraySet (typ, e, e', e'') ->
[ List
(Atom "array.set"
:: index st.type_names typ
:: (expression e @ expression e' @ expression e''))
]
| StructSet (typ, i, e, e') ->
[ List
(Atom "struct.set"
:: index st.type_names typ
:: Atom (string_of_int i)
:: (expression e @ expression e'))
]
| Return_call (f, l) ->
[ List
(Atom "return_call"
:: index st.func_names f
:: List.concat (List.map ~f:expression l))
]
| Return_call_ref (typ, e, l) ->
[ List
(Atom "return_call_ref"
:: index st.type_names typ
:: List.concat (List.map ~f:expression (l @ [ e ])))
]
| Unreachable -> [ List [ Atom "unreachable" ] ]
| Event Parse_info.{ src = None | Some ""; _ } -> [ Comment "@" ]
| Event Parse_info.{ src = Some src; col; line; _ } ->
let loc = Format.sprintf "%s:%d:%d" src line col in
[ Comment ("@ " ^ loc) ]
and instructions l = List.concat (List.map ~f:instruction l) in
expression, instructions
let expression ctx st = fst (expression_or_instructions ctx st false)
let instructions ctx st = snd (expression_or_instructions ctx st true)
let funct ctx st name exported_name typ signature param_names locals body =
let st =
{ st with
local_names =
assign_names
~reversed:false
Code.Var.get_name
(param_names @ List.map ~f:fst locals)
}
in
List
((Atom "func" :: index st.func_names name :: export exported_name)
@ (match typ with
| None -> []
| Some typ -> [ List [ Atom "type"; index st.type_names typ ] ])
@ func_type st ~param_names signature
@ List.map
~f:(fun (i, t) -> List [ Atom "local"; index st.local_names i; value_type st t ])
locals
@ instructions ctx st body)
let import st f =
match f with
| Function _ | Global _ | Data _ | Tag _ | Type _ -> []
| Import { import_module; import_name; name; desc } ->
[ List
[ Atom "import"
; quoted_name import_module
; quoted_name import_name
; List
(match desc with
| Fun typ -> Atom "func" :: index st.func_names name :: func_type st typ
| Global ty ->
[ Atom "global"; index st.global_names name; global_type st ty ]
| Tag ty ->
[ Atom "tag"
; index st.tag_names name
; List [ Atom "param"; value_type st ty ]
])
]
]
let type_field st { name; typ; supertype; final } =
if final && Option.is_none supertype
then List [ Atom "type"; index st.type_names name; str_type st typ ]
else
List
[ Atom "type"
; index st.type_names name
; List
(Atom "sub"
:: ((if final then [ Atom "final" ] else [])
@ (match supertype with
| Some supertype -> [ index st.type_names supertype ]
| None -> [])
@ [ str_type st typ ]))
]
let field ctx st f =
match f with
| Function { name; exported_name; typ; signature; param_names; locals; body } ->
[ funct ctx st name exported_name typ signature param_names locals body ]
| Global { name; exported_name; typ; init } ->
[ List
(Atom "global"
:: index st.global_names name
:: (export exported_name @ (global_type st typ :: expression ctx st init)))
]
| Tag { name; typ } ->
[ List
[ Atom "tag"
; index st.tag_names name
; List [ Atom "param"; value_type st typ ]
]
]
| Import _ -> []
| Data { name; contents } ->
[ List
[ Atom "data"
; index st.data_names name
; Atom ("\"" ^ escape_string contents ^ "\"")
]
]
| Type [ t ] -> [ type_field st t ]
| Type l -> [ List (Atom "rec" :: List.map ~f:(type_field st) l) ]
let times = Debug.find "times"
let f ch fields =
let t = Timer.make () in
let st = build_name_tables fields in
let ctx = { function_refs = Code.Var.Set.empty } in
let other_fields = List.concat_map ~f:(fun f -> field ctx st f) fields in
let funct_decl =
let functions = Code.Var.Set.elements ctx.function_refs in
if List.is_empty functions
then []
else
[ List
(Atom "elem"
:: Atom "declare"
:: Atom "func"
:: List.map ~f:(index st.func_names) functions)
]
in
let imports = List.concat_map ~f:(fun i -> import st i) fields in
let sexp = List (Atom "module" :: List.concat [ imports; funct_decl; other_fields ]) in
if times () then Format.eprintf " prepare: %a@." Timer.print t;
let t = Timer.make () in
Format.fprintf (Format.formatter_of_out_channel ch) "%a@." format_sexp sexp;
if times () then Format.eprintf " format: %a@." Timer.print t
|