(* Title: Tools/Compute_Oracle/compute.ML
ID: $Id$
Author: Steven Obua
*)
signature COMPUTE = sig
type computer
datatype machine = BARRAS | BARRAS_COMPILED | HASKELL | SML
exception Make of string
val make : machine -> theory -> thm list -> computer
exception Compute of string
val compute : computer -> (int -> string) -> cterm -> term
val theory_of : computer -> theory
val hyps_of : computer -> term list
val shyps_of : computer -> sort list
val rewrite_param : computer -> (int -> string) -> cterm -> thm
val rewrite : computer -> cterm -> thm
val discard : computer -> unit
val setup : theory -> theory
val print_encoding : bool ref
end
structure Compute :> COMPUTE = struct
val print_encoding = ref false
datatype machine = BARRAS | BARRAS_COMPILED | HASKELL | SML
(* Terms are mapped to integer codes *)
structure Encode :>
sig
type encoding
val empty : encoding
val insert : term -> encoding -> int * encoding
val lookup_code : term -> encoding -> int option
val lookup_term : int -> encoding -> term option
val remove_code : int -> encoding -> encoding
val remove_term : term -> encoding -> encoding
val fold : ((term * int) -> 'a -> 'a) -> encoding -> 'a -> 'a
end
=
struct
type encoding = int * (int Termtab.table) * (term Inttab.table)
val empty = (0, Termtab.empty, Inttab.empty)
fun insert t (e as (count, term2int, int2term)) =
(case Termtab.lookup term2int t of
NONE => (count, (count+1, Termtab.update_new (t, count) term2int, Inttab.update_new (count, t) int2term))
| SOME code => (code, e))
fun lookup_code t (_, term2int, _) = Termtab.lookup term2int t
fun lookup_term c (_, _, int2term) = Inttab.lookup int2term c
fun remove_code c (e as (count, term2int, int2term)) =
(case lookup_term c e of NONE => e | SOME t => (count, Termtab.delete t term2int, Inttab.delete c int2term))
fun remove_term t (e as (count, term2int, int2term)) =
(case lookup_code t e of NONE => e | SOME c => (count, Termtab.delete t term2int, Inttab.delete c int2term))
fun fold f (_, term2int, _) = Termtab.fold f term2int
end
exception Make of string;
exception Compute of string;
local
fun make_constant t ty encoding =
let
val (code, encoding) = Encode.insert t encoding
in
(encoding, AbstractMachine.Const code)
end
in
fun remove_types encoding t =
case t of
Var (_, ty) => make_constant t ty encoding
| Free (_, ty) => make_constant t ty encoding
| Const (_, ty) => make_constant t ty encoding
| Abs (_, ty, t') =>
let val (encoding, t'') = remove_types encoding t' in
(encoding, AbstractMachine.Abs t'')
end
| a $ b =>
let
val (encoding, a) = remove_types encoding a
val (encoding, b) = remove_types encoding b
in
(encoding, AbstractMachine.App (a,b))
end
| Bound b => (encoding, AbstractMachine.Var b)
end
local
fun type_of (Free (_, ty)) = ty
| type_of (Const (_, ty)) = ty
| type_of (Var (_, ty)) = ty
| type_of _ = sys_error "infer_types: type_of error"
in
fun infer_types naming encoding =
let
fun infer_types _ bounds _ (AbstractMachine.Var v) = (Bound v, List.nth (bounds, v))
| infer_types _ bounds _ (AbstractMachine.Const code) =
let
val c = the (Encode.lookup_term code encoding)
in
(c, type_of c)
end
| infer_types level bounds _ (AbstractMachine.App (a, b)) =
let
val (a, aty) = infer_types level bounds NONE a
val (adom, arange) =
case aty of
Type ("fun", [dom, range]) => (dom, range)
| _ => sys_error "infer_types: function type expected"
val (b, bty) = infer_types level bounds (SOME adom) b
in
(a $ b, arange)
end
| infer_types level bounds (SOME (ty as Type ("fun", [dom, range]))) (AbstractMachine.Abs m) =
let
val (m, _) = infer_types (level+1) (dom::bounds) (SOME range) m
in
(Abs (naming level, dom, m), ty)
end
| infer_types _ _ NONE (AbstractMachine.Abs m) = sys_error "infer_types: cannot infer type of abstraction"
fun infer ty term =
let
val (term', _) = infer_types 0 [] (SOME ty) term
in
term'
end
in
infer
end
end
datatype prog =
ProgBarras of AM_Interpreter.program
| ProgBarrasC of AM_Compiler.program
| ProgHaskell of AM_GHC.program
| ProgSML of AM_SML.program
structure Sorttab = TableFun(type key = sort val ord = Term.sort_ord)
datatype computer = Computer of theory_ref * Encode.encoding * term list * unit Sorttab.table * prog
datatype cthm = ComputeThm of term list * sort list * term
fun thm2cthm th =
let
val {hyps, prop, tpairs, shyps, ...} = Thm.rep_thm th
val _ = if not (null tpairs) then raise Make "theorems may not contain tpairs" else ()
in
ComputeThm (hyps, shyps, prop)
end
fun make machine thy raw_ths =
let
fun transfer (x:thm) = Thm.transfer thy x
val ths = map (thm2cthm o Thm.strip_shyps o transfer) raw_ths
fun thm2rule (encoding, hyptable, shyptable) th =
let
val (ComputeThm (hyps, shyps, prop)) = th
val hyptable = fold (fn h => Termtab.update (h, ())) hyps hyptable
val shyptable = fold (fn sh => Sorttab.update (sh, ())) shyps shyptable
val (prems, prop) = (Logic.strip_imp_prems prop, Logic.strip_imp_concl prop)
val (a, b) = Logic.dest_equals prop
handle TERM _ => raise (Make "theorems must be meta-level equations (with optional guards)")
val a = Envir.eta_contract a
val b = Envir.eta_contract b
val prems = map Envir.eta_contract prems
val (encoding, left) = remove_types encoding a
val (encoding, right) = remove_types encoding b
fun remove_types_of_guard encoding g =
(let
val (t1, t2) = Logic.dest_equals g
val (encoding, t1) = remove_types encoding t1
val (encoding, t2) = remove_types encoding t2
in
(encoding, AbstractMachine.Guard (t1, t2))
end handle TERM _ => raise (Make "guards must be meta-level equations"))
val (encoding, prems) = fold_rev (fn p => fn (encoding, ps) => let val (e, p) = remove_types_of_guard encoding p in (e, p::ps) end) prems (encoding, [])
fun make_pattern encoding n vars (var as AbstractMachine.Abs _) =
raise (Make "no lambda abstractions allowed in pattern")
| make_pattern encoding n vars (var as AbstractMachine.Var _) =
raise (Make "no bound variables allowed in pattern")
| make_pattern encoding n vars (AbstractMachine.Const code) =
(case the (Encode.lookup_term code encoding) of
Var _ => ((n+1, Inttab.update_new (code, n) vars, AbstractMachine.PVar)
handle Inttab.DUP _ => raise (Make "no duplicate variable in pattern allowed"))
| _ => (n, vars, AbstractMachine.PConst (code, [])))
| make_pattern encoding n vars (AbstractMachine.App (a, b)) =
let
val (n, vars, pa) = make_pattern encoding n vars a
val (n, vars, pb) = make_pattern encoding n vars b
in
case pa of
AbstractMachine.PVar =>
raise (Make "patterns may not start with a variable")
| AbstractMachine.PConst (c, args) =>
(n, vars, AbstractMachine.PConst (c, args@[pb]))
end
(* Principally, a check should be made here to see if the (meta-) hyps contain any of the variables of the rule.
As it is, all variables of the rule are schematic, and there are no schematic variables in meta-hyps, therefore
this check can be left out. *)
val (vcount, vars, pattern) = make_pattern encoding 0 Inttab.empty left
val _ = (case pattern of
AbstractMachine.PVar =>
raise (Make "patterns may not start with a variable")
(* | AbstractMachine.PConst (_, []) =>
(print th; raise (Make "no parameter rewrite found"))*)
| _ => ())
(* finally, provide a function for renaming the
pattern bound variables on the right hand side *)
fun rename level vars (var as AbstractMachine.Var _) = var
| rename level vars (c as AbstractMachine.Const code) =
(case Inttab.lookup vars code of
NONE => c
| SOME n => AbstractMachine.Var (vcount-n-1+level))
| rename level vars (AbstractMachine.App (a, b)) =
AbstractMachine.App (rename level vars a, rename level vars b)
| rename level vars (AbstractMachine.Abs m) =
AbstractMachine.Abs (rename (level+1) vars m)
fun rename_guard (AbstractMachine.Guard (a,b)) =
AbstractMachine.Guard (rename 0 vars a, rename 0 vars b)
in
((encoding, hyptable, shyptable), (map rename_guard prems, pattern, rename 0 vars right))
end
val ((encoding, hyptable, shyptable), rules) =
fold_rev (fn th => fn (encoding_hyptable, rules) =>
let
val (encoding_hyptable, rule) = thm2rule encoding_hyptable th
in (encoding_hyptable, rule::rules) end)
ths ((Encode.empty, Termtab.empty, Sorttab.empty), [])
val prog =
case machine of
BARRAS => ProgBarras (AM_Interpreter.compile rules)
| BARRAS_COMPILED => ProgBarrasC (AM_Compiler.compile rules)
| HASKELL => ProgHaskell (AM_GHC.compile rules)
| SML => ProgSML (AM_SML.compile rules)
fun has_witness s = not (null (Sign.witness_sorts thy [] [s]))
val shyptable = fold Sorttab.delete (filter has_witness (Sorttab.keys (shyptable))) shyptable
in Computer (Theory.check_thy thy, encoding, Termtab.keys hyptable, shyptable, prog) end
(*fun timeit f =
let
val t1 = Time.toMicroseconds (Time.now ())
val x = f ()
val t2 = Time.toMicroseconds (Time.now ())
val _ = writeln ("### time = "^(Real.toString ((Real.fromLargeInt t2 - Real.fromLargeInt t1)/(1000000.0)))^"s")
in
x
end*)
fun report s f = f () (*writeln s; timeit f*)
fun compute (Computer (rthy, encoding, hyps, shyptable, prog)) naming ct =
let
fun run (ProgBarras p) = AM_Interpreter.run p
| run (ProgBarrasC p) = AM_Compiler.run p
| run (ProgHaskell p) = AM_GHC.run p
| run (ProgSML p) = AM_SML.run p
val {t=t, T=ty, thy=ctthy, ...} = rep_cterm ct
val thy = Theory.merge (Theory.deref rthy, ctthy)
val (encoding, t) = report "remove_types" (fn () => remove_types encoding t)
val _ = if (!print_encoding) then writeln (makestring ("encoding: ",Encode.fold (fn x => fn s => x::s) encoding [])) else ()
val t = report "run" (fn () => run prog t)
val t = report "infer_types" (fn () => infer_types naming encoding ty t)
in
t
end
fun discard (Computer (rthy, encoding, hyps, shyptable, prog)) =
(case prog of
ProgBarras p => AM_Interpreter.discard p
| ProgBarrasC p => AM_Compiler.discard p
| ProgHaskell p => AM_GHC.discard p
| ProgSML p => AM_SML.discard p)
fun theory_of (Computer (rthy, _, _,_,_)) = Theory.deref rthy
fun hyps_of (Computer (_, _, hyps, _, _)) = hyps
fun shyps_of (Computer (_, _, _, shyptable, _)) = Sorttab.keys (shyptable)
fun shyptab_of (Computer (_, _, _, shyptable, _)) = shyptable
fun default_naming i = "v_" ^ Int.toString i
exception Param of computer * (int -> string) * cterm;
fun rewrite_param r n ct =
let
val thy = theory_of_cterm ct
val th = timeit (fn () => invoke_oracle_i thy "Compute_Oracle.compute" (thy, Param (r, n, ct)))
val hyps = map (fn h => assume (cterm_of thy h)) (hyps_of r)
in
fold (fn h => fn p => implies_elim p h) hyps th
end
(*fun rewrite_param r n ct =
let
val hyps = hyps_of r
val shyps = shyps_of r
val thy = theory_of_cterm ct
val _ = Theory.assert_super (theory_of r) thy
val t' = timeit (fn () => compute r n ct)
val eq = Logic.mk_equals (term_of ct, t')
in
Thm.unchecked_oracle thy "Compute.compute" (eq, hyps, shyps)
end*)
fun rewrite r ct = rewrite_param r default_naming ct
(* theory setup *)
fun compute_oracle (thy, Param (r, naming, ct)) =
let
val _ = Theory.assert_super (theory_of r) thy
val t' = timeit (fn () => compute r naming ct)
val eq = Logic.mk_equals (term_of ct, t')
val hyps = hyps_of r
val shyptab = shyptab_of r
fun delete s shyptab = Sorttab.delete s shyptab handle Sorttab.UNDEF _ => shyptab
fun delete_term t shyptab = fold delete (Sorts.insert_term t []) shyptab
val shyps = if Sorttab.is_empty shyptab then [] else Sorttab.keys (fold delete_term (eq::hyps) shyptab)
val _ = if not (null shyps) then raise Compute ("dangling sort hypotheses: "^(makestring shyps)) else ()
in
fold_rev (fn hyp => fn p => Logic.mk_implies (hyp, p)) hyps eq
end
| compute_oracle _ = raise Match
val setup = (fn thy => (writeln "install oracle"; Theory.add_oracle ("compute", compute_oracle) thy))
(*val _ = Context.add_setup (Theory.add_oracle ("compute", compute_oracle))*)
end