faster preprocessing: before applying a step, test if it is applicable (normalization of binders, unfolding of abs/min/max definitions, lambda lifting, explicit application, monomorphization),
custom-made (top-down) atomize_conv,
store predicate and function symbols in a table instead of a list for faster lookup,
updated certificates
(* Title: HOL/SMT/Tools/smt_translate.ML
Author: Sascha Boehme, TU Muenchen
Translate theorems into an SMT intermediate format and serialize them,
depending on an SMT interface.
*)
signature SMT_TRANSLATE =
sig
(* intermediate term structure *)
datatype sym =
SConst of string * typ |
SFree of string * typ |
SNum of int * typ
datatype squant = SForall | SExists
datatype 'a spattern = SPat of 'a list | SNoPat of 'a list
datatype ('a, 'b) sterm =
SVar of int |
SApp of 'a * ('a, 'b) sterm list |
SLet of (string * 'b) * ('a, 'b) sterm * ('a, 'b) sterm |
SQuant of squant * (string * 'b) list * ('a, 'b) sterm spattern list *
('a, 'b) sterm
(* table for built-in symbols *)
type builtin_fun = typ -> (sym, typ) sterm list ->
(string * (sym, typ) sterm list) option
type builtin_table = (typ * builtin_fun) list Symtab.table
val builtin_make: (term * string) list -> builtin_table
val builtin_add: term * builtin_fun -> builtin_table -> builtin_table
val builtin_lookup: builtin_table -> theory -> string * typ ->
(sym, typ) sterm list -> (string * (sym, typ) sterm list) option
val bv_rotate: (int -> string) -> builtin_fun
val bv_extend: (int -> string) -> builtin_fun
val bv_extract: (int -> int -> string) -> builtin_fun
(* configuration options *)
type prefixes = {
var_prefix: string,
typ_prefix: string,
fun_prefix: string,
pred_prefix: string }
type markers = {
term_marker: string,
formula_marker: string }
type builtins = {
builtin_typ: typ -> string option,
builtin_num: int * typ -> string option,
builtin_fun: bool -> builtin_table }
type sign = {
typs: string list,
funs: (string * (string list * string)) list,
preds: (string * string list) list }
type config = {
strict: bool,
prefixes: prefixes,
markers: markers,
builtins: builtins,
serialize: sign -> (string, string) sterm list -> TextIO.outstream -> unit}
type recon = {typs: typ Symtab.table, terms: term Symtab.table}
val translate: config -> theory -> thm list -> TextIO.outstream ->
recon * thm list
val dest_binT: typ -> int
val dest_funT: int -> typ -> typ list * typ
end
structure SMT_Translate: SMT_TRANSLATE =
struct
(* Intermediate term structure *)
datatype sym =
SConst of string * typ |
SFree of string * typ |
SNum of int * typ
datatype squant = SForall | SExists
datatype 'a spattern = SPat of 'a list | SNoPat of 'a list
datatype ('a, 'b) sterm =
SVar of int |
SApp of 'a * ('a, 'b) sterm list |
SLet of (string * 'b) * ('a, 'b) sterm * ('a, 'b) sterm |
SQuant of squant * (string * 'b) list * ('a, 'b) sterm spattern list *
('a, 'b) sterm
fun app c ts = SApp (c, ts)
fun map_pat f (SPat ps) = SPat (map f ps)
| map_pat f (SNoPat ps) = SNoPat (map f ps)
fun fold_map_pat f (SPat ps) = fold_map f ps #>> SPat
| fold_map_pat f (SNoPat ps) = fold_map f ps #>> SNoPat
val make_sconst = SConst o Term.dest_Const
(* General type destructors. *)
fun dest_binT T =
(case T of
Type (@{type_name "Numeral_Type.num0"}, _) => 0
| Type (@{type_name "Numeral_Type.num1"}, _) => 1
| Type (@{type_name "Numeral_Type.bit0"}, [T]) => 2 * dest_binT T
| Type (@{type_name "Numeral_Type.bit1"}, [T]) => 1 + 2 * dest_binT T
| _ => raise TYPE ("dest_binT", [T], []))
val dest_wordT = (fn
Type (@{type_name "word"}, [T]) => dest_binT T
| T => raise TYPE ("dest_wordT", [T], []))
val dest_funT =
let
fun dest Ts 0 T = (rev Ts, T)
| dest Ts i (Type ("fun", [T, U])) = dest (T::Ts) (i-1) U
| dest _ _ T = raise TYPE ("dest_funT", [T], [])
in dest [] end
(* Table for built-in symbols *)
type builtin_fun = typ -> (sym, typ) sterm list ->
(string * (sym, typ) sterm list) option
type builtin_table = (typ * builtin_fun) list Symtab.table
fun builtin_make entries =
let
fun dest (t, bn) =
let val (n, T) = Term.dest_Const t
in (n, (Logic.varifyT T, K (SOME o pair bn))) end
in Symtab.make (AList.group (op =) (map dest entries)) end
fun builtin_add (t, f) tab =
let val (n, T) = apsnd Logic.varifyT (Term.dest_Const t)
in Symtab.map_default (n, []) (AList.update (op =) (T, f)) tab end
fun builtin_lookup tab thy (n, T) ts =
AList.lookup (Sign.typ_instance thy) (Symtab.lookup_list tab n) T
|> (fn SOME f => f T ts | NONE => NONE)
local
val dest_nat = (fn
SApp (SConst (@{const_name nat}, _), [SApp (SNum (i, _), _)]) => SOME i
| _ => NONE)
in
fun bv_rotate mk_name _ ts =
dest_nat (hd ts) |> Option.map (fn i => (mk_name i, tl ts))
fun bv_extend mk_name T ts =
(case (try dest_wordT (domain_type T), try dest_wordT (range_type T)) of
(SOME i, SOME j) => if j - i >= 0 then SOME (mk_name (j - i), ts) else NONE
| _ => NONE)
fun bv_extract mk_name T ts =
(case (try dest_wordT (body_type T), dest_nat (hd ts)) of
(SOME i, SOME lb) => SOME (mk_name (i + lb - 1) lb, tl ts)
| _ => NONE)
end
(* Configuration options *)
type prefixes = {
var_prefix: string,
typ_prefix: string,
fun_prefix: string,
pred_prefix: string }
type markers = {
term_marker: string,
formula_marker: string }
type builtins = {
builtin_typ: typ -> string option,
builtin_num: int * typ -> string option,
builtin_fun: bool -> builtin_table }
type sign = {
typs: string list,
funs: (string * (string list * string)) list,
preds: (string * string list) list }
type config = {
strict: bool,
prefixes: prefixes,
markers: markers,
builtins: builtins,
serialize: sign -> (string, string) sterm list -> TextIO.outstream -> unit}
type recon = {typs: typ Symtab.table, terms: term Symtab.table}
(* Translate Isabelle/HOL terms into SMT intermediate terms.
We assume that lambda-lifting has been performed before, i.e., lambda
abstractions occur only at quantifiers and let expressions.
*)
local
val quantifier = (fn
@{const_name All} => SOME SForall
| @{const_name Ex} => SOME SExists
| _ => NONE)
fun group_quant qname vs (t as Const (q, _) $ Abs (n, T, u)) =
if q = qname then group_quant qname ((n, T) :: vs) u else (vs, t)
| group_quant _ vs t = (vs, t)
fun dest_trigger (@{term trigger} $ tl $ t) = (HOLogic.dest_list tl, t)
| dest_trigger t = ([], t)
fun pat f ts (Const (@{const_name pat}, _) $ t) = SPat (rev (f t :: ts))
| pat f ts (Const (@{const_name nopat}, _) $ t) = SNoPat (rev (f t :: ts))
| pat f ts (Const (@{const_name andpat}, _) $ p $ t) = pat f (f t :: ts) p
| pat _ _ t = raise TERM ("pat", [t])
fun trans Ts t =
(case Term.strip_comb t of
(Const (qn, _), [Abs (n, T, t1)]) =>
(case quantifier qn of
SOME q =>
let
val (vs, u) = group_quant qn [(n, T)] t1
val Us = map snd vs @ Ts
val (ps, b) = dest_trigger u
in SQuant (q, rev vs, map (pat (trans Us) []) ps, trans Us b) end
| NONE => raise TERM ("intermediate", [t]))
| (Const (@{const_name Let}, _), [t1, Abs (n, T, t2)]) =>
SLet ((n, T), trans Ts t1, trans (T :: Ts) t2)
| (Const (c as (@{const_name distinct}, _)), [t1]) =>
(* this is not type-correct, but will be corrected at a later stage *)
SApp (SConst c, map (trans Ts) (HOLogic.dest_list t1))
| (Const c, ts) =>
(case try HOLogic.dest_number t of
SOME (T, i) => SApp (SNum (i, T), [])
| NONE => SApp (SConst c, map (trans Ts) ts))
| (Free c, ts) => SApp (SFree c, map (trans Ts) ts)
| (Bound i, []) => SVar i
| _ => raise TERM ("intermediate", [t]))
in
fun intermediate ts = map (trans [] o HOLogic.dest_Trueprop) ts
end
(* Separate formulas from terms by adding special marker symbols ("term",
"formula"). Atoms "P" whose head symbol also occurs as function symbol are
rewritten to "term P = term True". Connectives and built-in predicates
occurring at term level are replaced by new constants, and theorems
specifying their meaning are added.
*)
local
local
fun cons_nr (SConst _) = 0
| cons_nr (SFree _) = 1
| cons_nr (SNum _) = 2
fun struct_ord (t, u) = int_ord (cons_nr t, cons_nr u)
fun atoms_ord (SConst (n, _), SConst (m, _)) = fast_string_ord (n, m)
| atoms_ord (SFree (n, _), SFree (m, _)) = fast_string_ord (n, m)
| atoms_ord (SNum (i, _), SNum (j, _)) = int_ord (i, j)
| atoms_ord _ = sys_error "atoms_ord"
fun types_ord (SConst (_, T), SConst (_, U)) = TermOrd.typ_ord (T, U)
| types_ord (SFree (_, T), SFree (_, U)) = TermOrd.typ_ord (T, U)
| types_ord (SNum (_, T), SNum (_, U)) = TermOrd.typ_ord (T, U)
| types_ord _ = sys_error "types_ord"
fun fast_sym_ord tu =
(case struct_ord tu of
EQUAL => (case atoms_ord tu of EQUAL => types_ord tu | ord => ord)
| ord => ord)
in
structure Stab = Table(type key = sym val ord = fast_sym_ord)
end
(** Add the marker symbols "term" and "formula" to separate formulas and
terms. **)
val connectives = map make_sconst [@{term True}, @{term False},
@{term Not}, @{term "op &"}, @{term "op |"}, @{term "op -->"},
@{term "op = :: bool => _"}]
fun insert_sym c = Stab.map_default (c, ()) I
fun note false c (ps, fs) = (insert_sym c ps, fs)
| note true c (ps, fs) = (ps, insert_sym c fs)
val term_marker = SConst (@{const_name term}, Term.dummyT)
val formula_marker = SConst (@{const_name formula}, Term.dummyT)
fun mark f true t = f true t #>> app term_marker o single
| mark f false t = f false t #>> app formula_marker o single
fun mark' f false t = f true t #>> app term_marker o single
| mark' f true t = f true t
val mark_term = app term_marker o single
fun lift_term_marker c ts =
let val rem = (fn SApp (SConst (@{const_name term}, _), [t]) => t | t => t)
in mark_term (SApp (c, map rem ts)) end
fun is_term (SApp (SConst (@{const_name term}, _), _)) = true
| is_term _ = false
fun either x = (fn y as SOME _ => y | _ => x)
fun get_loc loc i t =
(case t of
SVar j => if i = j then SOME loc else NONE
| SApp (SConst (@{const_name term}, _), us) => get_locs true i us
| SApp (SConst (@{const_name formula}, _), us) => get_locs false i us
| SApp (_, us) => get_locs loc i us
| SLet (_, u1, u2) => either (get_loc true i u1) (get_loc loc (i+1) u2)
| SQuant (_, vs, _, u) => get_loc loc (i + length vs) u)
and get_locs loc i ts = fold (either o get_loc loc i) ts NONE
fun sep loc t =
(case t of
SVar _ => pair t
| SApp (c as SConst (@{const_name If}, _), u :: us) =>
mark sep false u ##>> fold_map (sep loc) us #>> app c o (op ::)
| SApp (c, us) =>
if not loc andalso member (op =) connectives c
then fold_map (sep loc) us #>> app c
else note loc c #> fold_map (mark' sep loc) us #>> app c
| SLet (v, u1, u2) =>
sep loc u2 #-> (fn u2' =>
mark sep (the (get_loc loc 0 u2')) u1 #>> (fn u1' =>
SLet (v, u1', u2')))
| SQuant (q, vs, ps, u) =>
fold_map (fold_map_pat (mark sep true)) ps ##>>
sep loc u #>> (fn (ps', u') =>
SQuant (q, vs, ps', u')))
(** Rewrite atoms. **)
val unterm_rule = @{lemma "term x == x" by (simp add: term_def)}
val unterm_conv = More_Conv.top_sweep_conv (K (Conv.rewr_conv unterm_rule))
val dest_word_type = (fn Type (@{type_name word}, [T]) => T | T => T)
fun instantiate [] _ = I
| instantiate (v :: _) T =
Term.subst_TVars [(v, dest_word_type (Term.domain_type T))]
fun dest_alls (Const (@{const_name All}, _) $ Abs (_, _, t)) = dest_alls t
| dest_alls t = t
val dest_iff = (fn (Const (@{const_name iff}, _) $ t $ _ ) => t | t => t)
val dest_eq = (fn (Const (@{const_name "op ="}, _) $ t $ _ ) => t | t => t)
val dest_not = (fn (@{term Not} $ t) => t | t => t)
val head_of = HOLogic.dest_Trueprop #> dest_alls #> dest_iff #> dest_not #>
dest_eq #> Term.head_of
fun prepare ctxt thm =
let
val rule = Conv.fconv_rule (unterm_conv ctxt) thm
val prop = Thm.prop_of thm
val inst = instantiate (Term.add_tvar_names prop [])
fun inst_for T = (rule, singleton intermediate (inst T prop))
in (make_sconst (head_of (Thm.prop_of rule)), inst_for) end
val logicals = map (prepare @{context})
@{lemma
"~ holds False"
"ALL p. holds (~ p) iff (~ holds p)"
"ALL p q. holds (p & q) iff (holds p & holds q)"
"ALL p q. holds (p | q) iff (holds p | holds q)"
"ALL p q. holds (p --> q) iff (holds p --> holds q)"
"ALL p q. holds (p iff q) iff (holds p iff holds q)"
"ALL p q. holds (p = q) iff (p = q)"
"ALL (a::int) b. holds (a < b) iff (a < b)"
"ALL (a::int) b. holds (a <= b) iff (a <= b)"
"ALL (a::real) b. holds (a < b) iff (a < b)"
"ALL (a::real) b. holds (a <= b) iff (a <= b)"
"ALL (a::'a::len0 word) b. holds (a < b) iff (a < b)"
"ALL (a::'a::len0 word) b. holds (a <= b) iff (a <= b)"
"ALL a b. holds (a <s b) iff (a <s b)"
"ALL a b. holds (a <=s b) iff (a <=s b)"
by (simp_all add: term_def iff_def)}
fun is_instance thy (SConst (n, T), SConst (m, U)) =
(n = m) andalso Sign.typ_instance thy (T, U)
| is_instance _ _ = false
fun rule_for thy c T =
AList.lookup (is_instance thy) logicals c
|> Option.map (fn inst_for => inst_for T)
fun lookup_logical thy (c as SConst (_, T)) (thms, ts) =
(case rule_for thy c T of
SOME (thm, t) => (thm :: thms, t :: ts)
| NONE => (thms, ts))
| lookup_logical _ _ tss = tss
val s_eq = make_sconst @{term "op = :: bool => _"}
val s_True = mark_term (SApp (make_sconst @{term True}, []))
fun holds (SApp (c, ts)) = SApp (s_eq, [lift_term_marker c ts, s_True])
| holds t = SApp (s_eq, [mark_term t, s_True])
val rewr_iff = (fn
SConst (@{const_name "op ="}, T as @{typ "bool => bool => bool"}) =>
SConst (@{const_name iff}, T)
| c => c)
fun rewrite ls =
let
fun rewr env loc t =
(case t of
SVar i => if not loc andalso nth env i then holds t else t
| SApp (c as SConst (@{const_name term}, _), [u]) =>
SApp (c, [rewr env true u])
| SApp (c as SConst (@{const_name formula}, _), [u]) =>
SApp (c, [rewr env false u])
| SApp (c, us) =>
let val f = if not loc andalso Stab.defined ls c then holds else I
in f (SApp (rewr_iff c, map (rewr env loc) us)) end
| SLet (v, u1, u2) =>
SLet (v, rewr env loc u1, rewr (is_term u1 :: env) loc u2)
| SQuant (q, vs, ps, u) =>
let val e = replicate (length vs) true @ env
in SQuant (q, vs, map (map_pat (rewr e loc)) ps, rewr e loc u) end)
in map (rewr [] false) end
in
fun separate thy ts =
let
val (ts', (ps, fs)) = fold_map (sep false) ts (Stab.empty, Stab.empty)
fun insert (px as (p, _)) = if Stab.defined fs p then Stab.update px else I
in
Stab.fold (lookup_logical thy o fst) fs ([], [])
||> append (rewrite (Stab.fold insert ps Stab.empty) ts')
end
end
(* Collect the signature of intermediate terms, identify built-in symbols,
rename uninterpreted symbols and types, make bound variables unique.
We require @{term distinct} to be a built-in constant of the SMT solver.
*)
local
fun empty_nctxt p = (p, 1)
fun make_nctxt (pT, pf, pp) = (empty_nctxt pT, empty_nctxt (pf, pp))
fun fresh_name (p, i) = (p ^ string_of_int i, (p, i+1))
fun fresh_typ (nT, nfp) = fresh_name nT ||> (fn nT' => (nT', nfp))
fun fresh_fun loc (nT, ((pf, pp), i)) =
let val p = if loc then pf else pp
in fresh_name (p, i) ||> (fn (_, i') => (nT, ((pf, pp), i'))) end
val empty_sign = (Typtab.empty, Termtab.empty, Termtab.empty)
fun lookup_typ (typs, _, _) = Typtab.lookup typs
fun lookup_fun true (_, funs, _) = Termtab.lookup funs
| lookup_fun false (_, _, preds) = Termtab.lookup preds
fun add_typ x (typs, funs, preds) = (Typtab.update x typs, funs, preds)
fun add_fun true x (typs, funs, preds) = (typs, Termtab.update x funs, preds)
| add_fun false x (typs, funs, preds) = (typs, funs, Termtab.update x preds)
fun make_sign (typs, funs, preds) = {
typs = map snd (Typtab.dest typs),
funs = map snd (Termtab.dest funs),
preds = map (apsnd fst o snd) (Termtab.dest preds) }
fun make_rtab (typs, funs, preds) =
let
val rTs = Typtab.dest typs |> map swap |> Symtab.make
val rts = Termtab.dest funs @ Termtab.dest preds
|> map (apfst fst o swap) |> Symtab.make
in {typs=rTs, terms=rts} end
fun either f g x = (case f x of NONE => g x | y => y)
fun rep_typ ({builtin_typ, ...} : builtins) T (st as (vars, ns, sgn)) =
(case either builtin_typ (lookup_typ sgn) T of
SOME n => (n, st)
| NONE =>
let val (n, ns') = fresh_typ ns
in (n, (vars, ns', add_typ (T, n) sgn)) end)
fun rep_var bs (_, T) (vars, ns, sgn) =
let val (n', vars') = fresh_name vars
in (vars', ns, sgn) |> rep_typ bs T |>> pair n' end
fun rep_fun bs loc t T i (st as (_, _, sgn0)) =
(case lookup_fun loc sgn0 t of
SOME (n, _) => (n, st)
| NONE =>
let
val (Us, U) = dest_funT i T
val (uns, (vars, ns, sgn)) =
st |> fold_map (rep_typ bs) Us ||>> rep_typ bs U
val (n, ns') = fresh_fun loc ns
in (n, (vars, ns', add_fun loc (t, (n, uns)) sgn)) end)
fun rep_num (bs as {builtin_num, ...} : builtins) (i, T) st =
(case builtin_num (i, T) of
SOME n => (n, st)
| NONE => rep_fun bs true (HOLogic.mk_number T i) T 0 st)
in
fun signature_of prefixes markers builtins thy ts =
let
val {var_prefix, typ_prefix, fun_prefix, pred_prefix} = prefixes
val {formula_marker, term_marker} = markers
val {builtin_fun, ...} = builtins
fun sign loc t =
(case t of
SVar i => pair (SVar i)
| SApp (SConst (@{const_name term}, _), [u]) =>
sign true u #>> app term_marker o single
| SApp (SConst (@{const_name formula}, _), [u]) =>
sign false u #>> app formula_marker o single
| SApp (SConst (c as (_, T)), ts) =>
(case builtin_lookup (builtin_fun loc) thy c ts of
SOME (n, ts') => fold_map (sign loc) ts' #>> app n
| NONE =>
rep_fun builtins loc (Const c) T (length ts) ##>>
fold_map (sign loc) ts #>> SApp)
| SApp (SFree (c as (_, T)), ts) =>
rep_fun builtins loc (Free c) T (length ts) ##>>
fold_map (sign loc) ts #>> SApp
| SApp (SNum n, _) => rep_num builtins n #>> (fn n => SApp (n, []))
| SLet (v, u1, u2) =>
rep_var builtins v #-> (fn v' =>
sign loc u1 ##>> sign loc u2 #>> (fn (u1', u2') =>
SLet (v', u1', u2')))
| SQuant (q, vs, ps, u) =>
fold_map (rep_var builtins) vs ##>>
fold_map (fold_map_pat (sign loc)) ps ##>>
sign loc u #>> (fn ((vs', ps'), u') =>
SQuant (q, vs', ps', u')))
in
(empty_nctxt var_prefix, make_nctxt (typ_prefix, fun_prefix, pred_prefix),
empty_sign)
|> fold_map (sign false) ts
|> (fn (us, (_, _, sgn)) => (make_rtab sgn, (make_sign sgn, us)))
end
end
(* Combination of all translation functions and invocation of serialization. *)
fun translate config thy thms stream =
let val {strict, prefixes, markers, builtins, serialize} = config
in
map Thm.prop_of thms
|> SMT_Monomorph.monomorph thy
|> intermediate
|> (if strict then separate thy else pair [])
||>> signature_of prefixes markers builtins thy
||> (fn (sgn, ts) => serialize sgn ts stream)
|> (fn ((thms', rtab), _) => (rtab, thms' @ thms))
end
end