(* Title: Tools/Compute_Oracle/am_ghc.ML ID: $Id: am_ghc.ML,v 1.4 2007/10/27 16:37:32 obua Exp $ Author: Steven Obua *) structure AM_GHC : ABSTRACT_MACHINE = struct open AbstractMachine; type program = string * string * (int Inttab.table) fun count_patternvars PVar = 1 | count_patternvars (PConst (_, ps)) = List.foldl (fn (p, count) => (count_patternvars p)+count) 0 ps fun update_arity arity code a = (case Inttab.lookup arity code of NONE => Inttab.update_new (code, a) arity | SOME (a': int) => if a > a' then Inttab.update (code, a) arity else arity) (* We have to find out the maximal arity of each constant *) fun collect_pattern_arity PVar arity = arity | collect_pattern_arity (PConst (c, args)) arity = fold collect_pattern_arity args (update_arity arity c (length args)) local fun collect applevel (Var _) arity = arity | collect applevel (Const c) arity = update_arity arity c applevel | collect applevel (Abs m) arity = collect 0 m arity | collect applevel (App (a,b)) arity = collect 0 b (collect (applevel + 1) a arity) in fun collect_term_arity t arity = collect 0 t arity end fun nlift level n (Var m) = if m < level then Var m else Var (m+n) | nlift level n (Const c) = Const c | nlift level n (App (a,b)) = App (nlift level n a, nlift level n b) | nlift level n (Abs b) = Abs (nlift (level+1) n b) fun rep n x = if n = 0 then [] else x::(rep (n-1) x) fun adjust_rules rules = let val arity = fold (fn (p, t) => fn arity => collect_term_arity t (collect_pattern_arity p arity)) rules Inttab.empty fun arity_of c = the (Inttab.lookup arity c) fun adjust_pattern PVar = PVar | adjust_pattern (C as PConst (c, args)) = if (length args <> arity_of c) then raise Compile ("Constant inside pattern must have maximal arity") else C fun adjust_rule (PVar, t) = raise Compile ("pattern may not be a variable") | adjust_rule (rule as (p as PConst (c, args),t)) = let val _ = if not (check_freevars (count_patternvars p) t) then raise Compile ("unbound variables on right hand side") else () val args = map adjust_pattern args val len = length args val arity = arity_of c fun lift level n (Var m) = if m < level then Var m else Var (m+n) | lift level n (Const c) = Const c | lift level n (App (a,b)) = App (lift level n a, lift level n b) | lift level n (Abs b) = Abs (lift (level+1) n b) val lift = lift 0 fun adjust_term n t = if n=0 then t else adjust_term (n-1) (App (t, Var (n-1))) in if len = arity then rule else if arity >= len then (PConst (c, args @ (rep (arity-len) PVar)), adjust_term (arity-len) (lift (arity-len) t)) else (raise Compile "internal error in adjust_rule") end in (arity, map adjust_rule rules) end fun print_term arity_of n = let fun str x = string_of_int x fun protect_blank s = if exists_string Symbol.is_ascii_blank s then "(" ^ s ^")" else s fun print_apps d f [] = f | print_apps d f (a::args) = print_apps d ("app "^(protect_blank f)^" "^(protect_blank (print_term d a))) args and print_call d (App (a, b)) args = print_call d a (b::args) | print_call d (Const c) args = (case arity_of c of NONE => print_apps d ("Const "^(str c)) args | SOME a => let val len = length args in if a <= len then let val s = "c"^(str c)^(concat (map (fn t => " "^(protect_blank (print_term d t))) (List.take (args, a)))) in print_apps d s (List.drop (args, a)) end else let fun mk_apps n t = if n = 0 then t else mk_apps (n-1) (App (t, Var (n-1))) fun mk_lambdas n t = if n = 0 then t else mk_lambdas (n-1) (Abs t) fun append_args [] t = t | append_args (c::cs) t = append_args cs (App (t, c)) in print_term d (mk_lambdas (a-len) (mk_apps (a-len) (nlift 0 (a-len) (append_args args (Const c))))) end end) | print_call d t args = print_apps d (print_term d t) args and print_term d (Var x) = if x < d then "b"^(str (d-x-1)) else "x"^(str (n-(x-d)-1)) | print_term d (Abs c) = "Abs (\\b"^(str d)^" -> "^(print_term (d + 1) c)^")" | print_term d t = print_call d t [] in print_term 0 end fun print_rule arity_of (p, t) = let fun str x = Int.toString x fun print_pattern top n PVar = (n+1, "x"^(str n)) | print_pattern top n (PConst (c, [])) = (n, (if top then "c" else "C")^(str c)) | print_pattern top n (PConst (c, args)) = let val (n,s) = print_pattern_list (n, (if top then "c" else "C")^(str c)) args in (n, if top then s else "("^s^")") end and print_pattern_list r [] = r | print_pattern_list (n, p) (t::ts) = let val (n, t) = print_pattern false n t in print_pattern_list (n, p^" "^t) ts end val (n, pattern) = print_pattern true 0 p in pattern^" = "^(print_term arity_of n t) end fun group_rules rules = let fun add_rule (r as (PConst (c,_), _)) groups = let val rs = (case Inttab.lookup groups c of NONE => [] | SOME rs => rs) in Inttab.update (c, r::rs) groups end | add_rule _ _ = raise Compile "internal error group_rules" in fold_rev add_rule rules Inttab.empty end fun haskell_prog name rules = let val buffer = ref "" fun write s = (buffer := (!buffer)^s) fun writeln s = (write s; write "\n") fun writelist [] = () | writelist (s::ss) = (writeln s; writelist ss) fun str i = Int.toString i val (arity, rules) = adjust_rules rules val rules = group_rules rules val constants = Inttab.keys arity fun arity_of c = Inttab.lookup arity c fun rep_str s n = concat (rep n s) fun indexed s n = s^(str n) fun section n = if n = 0 then [] else (section (n-1))@[n-1] fun make_show c = let val args = section (the (arity_of c)) in " show ("^(indexed "C" c)^(concat (map (indexed " a") args))^") = " ^"\""^(indexed "C" c)^"\""^(concat (map (fn a => "++(show "^(indexed "a" a)^")") args)) end fun default_case c = let val args = concat (map (indexed " x") (section (the (arity_of c)))) in (indexed "c" c)^args^" = "^(indexed "C" c)^args end val _ = writelist [ "module "^name^" where", "", "data Term = Const Integer | App Term Term | Abs (Term -> Term)", " "^(concat (map (fn c => " | C"^(str c)^(rep_str " Term" (the (arity_of c)))) constants)), "", "instance Show Term where"] val _ = writelist (map make_show constants) val _ = writelist [ " show (Const c) = \"c\"++(show c)", " show (App a b) = \"A\"++(show a)++(show b)", " show (Abs _) = \"L\"", ""] val _ = writelist [ "app (Abs a) b = a b", "app a b = App a b", "", "calc s c = writeFile s (show c)", ""] fun list_group c = (writelist (case Inttab.lookup rules c of NONE => [default_case c, ""] | SOME (rs as ((PConst (_, []), _)::rs')) => if not (null rs') then raise Compile "multiple declaration of constant" else (map (print_rule arity_of) rs) @ [""] | SOME rs => (map (print_rule arity_of) rs) @ [default_case c, ""])) val _ = map list_group constants in (arity, !buffer) end val guid_counter = ref 0 fun get_guid () = let val c = !guid_counter val _ = guid_counter := !guid_counter + 1 in (LargeInt.toString (Time.toMicroseconds (Time.now ()))) ^ (string_of_int c) end fun tmp_file s = Path.implode (Path.expand (File.tmp_path (Path.make [s]))); fun wrap s = "\""^s^"\"" fun writeTextFile name s = File.write (Path.explode name) s val ghc = ref (case getenv "GHC_PATH" of "" => "ghc" | s => s) fun fileExists name = ((OS.FileSys.fileSize name; true) handle OS.SysErr _ => false) fun compile eqs = let val _ = if exists (fn (a,b,c) => not (null a)) eqs then raise Compile ("cannot deal with guards") else () val eqs = map (fn (a,b,c) => (b,c)) eqs val guid = get_guid () val module = "AMGHC_Prog_"^guid val (arity, source) = haskell_prog module eqs val module_file = tmp_file (module^".hs") val object_file = tmp_file (module^".o") val _ = writeTextFile module_file source val _ = system ((!ghc)^" -c "^module_file) val _ = if not (fileExists object_file) then raise Compile ("Failure compiling haskell code (GHC_PATH = '"^(!ghc)^"')") else () in (guid, module_file, arity) end fun readResultFile name = File.read (Path.explode name) fun parse_result arity_of result = let val result = String.explode result fun shift NONE x = SOME x | shift (SOME y) x = SOME (y*10 + x) fun parse_int' x (#"0"::rest) = parse_int' (shift x 0) rest | parse_int' x (#"1"::rest) = parse_int' (shift x 1) rest | parse_int' x (#"2"::rest) = parse_int' (shift x 2) rest | parse_int' x (#"3"::rest) = parse_int' (shift x 3) rest | parse_int' x (#"4"::rest) = parse_int' (shift x 4) rest | parse_int' x (#"5"::rest) = parse_int' (shift x 5) rest | parse_int' x (#"6"::rest) = parse_int' (shift x 6) rest | parse_int' x (#"7"::rest) = parse_int' (shift x 7) rest | parse_int' x (#"8"::rest) = parse_int' (shift x 8) rest | parse_int' x (#"9"::rest) = parse_int' (shift x 9) rest | parse_int' x rest = (x, rest) fun parse_int rest = parse_int' NONE rest fun parse (#"C"::rest) = (case parse_int rest of (SOME c, rest) => let val (args, rest) = parse_list (the (arity_of c)) rest fun app_args [] t = t | app_args (x::xs) t = app_args xs (App (t, x)) in (app_args args (Const c), rest) end | (NONE, rest) => raise Run "parse C") | parse (#"c"::rest) = (case parse_int rest of (SOME c, rest) => (Const c, rest) | _ => raise Run "parse c") | parse (#"A"::rest) = let val (a, rest) = parse rest val (b, rest) = parse rest in (App (a,b), rest) end | parse (#"L"::rest) = raise Run "there may be no abstraction in the result" | parse _ = raise Run "invalid result" and parse_list n rest = if n = 0 then ([], rest) else let val (x, rest) = parse rest val (xs, rest) = parse_list (n-1) rest in (x::xs, rest) end val (parsed, rest) = parse result fun is_blank (#" "::rest) = is_blank rest | is_blank (#"\n"::rest) = is_blank rest | is_blank [] = true | is_blank _ = false in if is_blank rest then parsed else raise Run "non-blank suffix in result file" end fun run (guid, module_file, arity) t = let val _ = if check_freevars 0 t then () else raise Run ("can only compute closed terms") fun arity_of c = Inttab.lookup arity c val callguid = get_guid() val module = "AMGHC_Prog_"^guid val call = module^"_Call_"^callguid val result_file = tmp_file (module^"_Result_"^callguid^".txt") val call_file = tmp_file (call^".hs") val term = print_term arity_of 0 t val call_source = "module "^call^" where\n\nimport "^module^"\n\ncall = "^module^".calc \""^result_file^"\" ("^term^")" val _ = writeTextFile call_file call_source val _ = system ((!ghc)^" -e \""^call^".call\" "^module_file^" "^call_file) val result = readResultFile result_file handle IO.Io _ => raise Run ("Failure running haskell compiler (GHC_PATH = '"^(!ghc)^"')") val t' = parse_result arity_of result val _ = OS.FileSys.remove call_file val _ = OS.FileSys.remove result_file in t' end fun discard _ = () end