12447
|
1 |
(* Title: HOL/recfun_codegen.ML
|
|
2 |
ID: $Id$
|
|
3 |
Author: Stefan Berghofer, TU Muenchen
|
|
4 |
License: GPL (GNU GENERAL PUBLIC LICENSE)
|
|
5 |
|
|
6 |
Code generator for recursive functions.
|
|
7 |
*)
|
|
8 |
|
|
9 |
signature RECFUN_CODEGEN =
|
|
10 |
sig
|
|
11 |
val add: theory attribute
|
|
12 |
val setup: (theory -> theory) list
|
|
13 |
end;
|
|
14 |
|
|
15 |
structure RecfunCodegen : RECFUN_CODEGEN =
|
|
16 |
struct
|
|
17 |
|
|
18 |
open Codegen;
|
|
19 |
|
12556
|
20 |
structure CodegenArgs =
|
12447
|
21 |
struct
|
|
22 |
val name = "HOL/recfun_codegen";
|
|
23 |
type T = thm list Symtab.table;
|
|
24 |
val empty = Symtab.empty;
|
|
25 |
val copy = I;
|
|
26 |
val prep_ext = I;
|
|
27 |
val merge = Symtab.merge_multi eq_thm;
|
|
28 |
fun print _ _ = ();
|
|
29 |
end;
|
|
30 |
|
12556
|
31 |
structure CodegenData = TheoryDataFun(CodegenArgs);
|
12447
|
32 |
|
|
33 |
val prop_of = #prop o rep_thm;
|
|
34 |
val dest_eqn = HOLogic.dest_eq o HOLogic.dest_Trueprop;
|
|
35 |
val const_of = dest_Const o head_of o fst o dest_eqn;
|
|
36 |
|
|
37 |
fun warn thm = warning ("RecfunCodegen: Not a proper equation:\n" ^
|
|
38 |
string_of_thm thm);
|
|
39 |
|
|
40 |
fun add (p as (thy, thm)) =
|
|
41 |
let
|
|
42 |
val tsig = Sign.tsig_of (sign_of thy);
|
12556
|
43 |
val tab = CodegenData.get thy;
|
12447
|
44 |
val (s, _) = const_of (prop_of thm);
|
|
45 |
|
|
46 |
val matches = curry
|
|
47 |
(Pattern.matches tsig o pairself (fst o dest_eqn o prop_of));
|
|
48 |
|
12556
|
49 |
in (CodegenData.put (Symtab.update ((s,
|
12447
|
50 |
filter_out (matches thm) (if_none (Symtab.lookup (tab, s)) []) @ [thm]),
|
|
51 |
tab)) thy, thm)
|
|
52 |
end handle TERM _ => (warn thm; p) | Pattern.Pattern => (warn thm; p);
|
|
53 |
|
|
54 |
fun get_equations thy (s, T) =
|
12556
|
55 |
(case Symtab.lookup (CodegenData.get thy, s) of
|
12447
|
56 |
None => []
|
|
57 |
| Some thms => filter (fn thm => is_instance thy T
|
|
58 |
(snd (const_of (prop_of thm)))) thms);
|
|
59 |
|
|
60 |
fun mk_poly_id thy (s, T) = mk_const_id (sign_of thy) s ^
|
|
61 |
(case get_defn thy s T of
|
|
62 |
Some (_, Some i) => "_def" ^ string_of_int i
|
|
63 |
| _ => "");
|
|
64 |
|
|
65 |
exception EQN of string * typ * string;
|
|
66 |
|
|
67 |
fun cycle g (xs, x) =
|
|
68 |
if x mem xs then xs
|
|
69 |
else foldl (cycle g) (x :: xs, flat (Graph.find_paths g (x, x)));
|
|
70 |
|
|
71 |
fun add_rec_funs thy gr dep eqs =
|
|
72 |
let
|
|
73 |
fun dest_eq t =
|
|
74 |
(mk_poly_id thy (const_of t), dest_eqn (rename_term t));
|
|
75 |
val eqs' = map dest_eq eqs;
|
|
76 |
val (dname, _) :: _ = eqs';
|
|
77 |
val (s, T) = const_of (hd eqs);
|
|
78 |
|
|
79 |
fun mk_fundef fname prfx gr [] = (gr, [])
|
|
80 |
| mk_fundef fname prfx gr ((fname', (lhs, rhs)) :: xs) =
|
|
81 |
let
|
|
82 |
val (gr1, pl) = invoke_codegen thy dname false (gr, lhs);
|
|
83 |
val (gr2, pr) = invoke_codegen thy dname false (gr1, rhs);
|
|
84 |
val (gr3, rest) = mk_fundef fname' "and " gr2 xs
|
|
85 |
in
|
|
86 |
(gr3, Pretty.blk (4, [Pretty.str (if fname = fname' then " | " else prfx),
|
|
87 |
pl, Pretty.str " =", Pretty.brk 1, pr]) :: rest)
|
|
88 |
end;
|
|
89 |
|
|
90 |
fun put_code fundef = Graph.map_node dname
|
|
91 |
(K (Some (EQN ("", dummyT, dname)), Pretty.string_of (Pretty.blk (0,
|
|
92 |
separate Pretty.fbrk fundef @ [Pretty.str ";"])) ^ "\n\n"));
|
|
93 |
|
|
94 |
in
|
|
95 |
(case try (Graph.get_node gr) dname of
|
|
96 |
None =>
|
|
97 |
let
|
|
98 |
val gr1 = Graph.add_edge (dname, dep)
|
|
99 |
(Graph.new_node (dname, (Some (EQN (s, T, "")), "")) gr);
|
|
100 |
val (gr2, fundef) = mk_fundef "" "fun " gr1 eqs';
|
|
101 |
val xs = cycle gr2 ([], dname);
|
|
102 |
val cs = map (fn x => case Graph.get_node gr2 x of
|
|
103 |
(Some (EQN (s, T, _)), _) => (s, T)
|
|
104 |
| _ => error ("RecfunCodegen: illegal cyclic dependencies:\n" ^
|
|
105 |
implode (separate ", " xs))) xs
|
|
106 |
in (case xs of
|
|
107 |
[_] => put_code fundef gr2
|
|
108 |
| _ =>
|
|
109 |
if not (dep mem xs) then
|
|
110 |
let
|
|
111 |
val eqs'' = map (dest_eq o prop_of)
|
|
112 |
(flat (map (get_equations thy) cs));
|
|
113 |
val (gr3, fundef') = mk_fundef "" "fun "
|
|
114 |
(Graph.add_edge (dname, dep)
|
|
115 |
(foldr (uncurry Graph.new_node) (map (fn k =>
|
|
116 |
(k, (Some (EQN ("", dummyT, dname)), ""))) xs,
|
|
117 |
Graph.del_nodes xs gr2))) eqs''
|
|
118 |
in put_code fundef' gr3 end
|
|
119 |
else gr2)
|
|
120 |
end
|
|
121 |
| Some (Some (EQN (_, _, s)), _) =>
|
|
122 |
if s = "" then
|
|
123 |
if dname = dep then gr else Graph.add_edge (dname, dep) gr
|
|
124 |
else if s = dep then gr else Graph.add_edge (s, dep) gr)
|
|
125 |
end;
|
|
126 |
|
|
127 |
fun recfun_codegen thy gr dep brack t = (case strip_comb t of
|
|
128 |
(Const p, ts) => (case get_equations thy p of
|
|
129 |
[] => None
|
|
130 |
| eqns =>
|
|
131 |
let val (gr', ps) = foldl_map (invoke_codegen thy dep true) (gr, ts)
|
|
132 |
in
|
|
133 |
Some (add_rec_funs thy gr' dep (map prop_of eqns),
|
|
134 |
mk_app brack (Pretty.str (mk_poly_id thy p)) ps)
|
|
135 |
end)
|
|
136 |
| _ => None);
|
|
137 |
|
|
138 |
|
|
139 |
val setup =
|
12556
|
140 |
[CodegenData.init,
|
12447
|
141 |
add_codegen "recfun" recfun_codegen,
|
12556
|
142 |
add_attribute "" add];
|
12447
|
143 |
|
|
144 |
end;
|