(* Title: HOL/Tools/Sledgehammer/sledgehammer_minimize.ML
Author: Philipp Meyer, TU Muenchen
Author: Jasmin Blanchette, TU Muenchen
Minimization of fact list for Metis using external provers.
*)
signature SLEDGEHAMMER_MINIMIZE =
sig
type stature = ATP_Problem_Generate.stature
type play = ATP_Proof_Reconstruct.play
type mode = Sledgehammer_Provers.mode
type params = Sledgehammer_Provers.params
type prover = Sledgehammer_Provers.prover
val binary_min_facts : int Config.T
val auto_minimize_min_facts : int Config.T
val auto_minimize_max_time : real Config.T
val minimize_facts :
string -> params -> bool -> int -> int -> Proof.state
-> ((string * stature) * thm list) list
-> ((string * stature) * thm list) list option
* ((unit -> play) * (play -> string) * string)
val get_minimizing_prover : Proof.context -> mode -> string -> prover
val run_minimize :
params -> int -> (Facts.ref * Attrib.src list) list -> Proof.state -> unit
end;
structure Sledgehammer_Minimize : SLEDGEHAMMER_MINIMIZE =
struct
open ATP_Util
open ATP_Proof
open ATP_Problem_Generate
open ATP_Proof_Reconstruct
open Sledgehammer_Util
open Sledgehammer_Fact
open Sledgehammer_Provers
(* wrapper for calling external prover *)
fun n_facts names =
let val n = length names in
string_of_int n ^ " fact" ^ plural_s n ^
(if n > 0 then
": " ^ (names |> map fst |> sort string_ord |> space_implode " ")
else
"")
end
fun print silent f = if silent then () else Output.urgent_message (f ())
fun test_facts ({debug, verbose, overlord, provers, max_mono_iters,
max_new_mono_instances, type_enc, strict, lam_trans,
uncurried_aliases, isar_proof, isar_shrink_factor,
preplay_timeout, ...} : params)
silent (prover : prover) timeout i n state facts =
let
val _ =
print silent (fn () =>
"Testing " ^ n_facts (map fst facts) ^
(if verbose then " (timeout: " ^ string_from_time timeout ^ ")"
else "") ^ "...")
val {goal, ...} = Proof.goal state
val facts =
facts |> maps (fn (n, ths) => ths |> map (Untranslated_Fact o pair n))
val params =
{debug = debug, verbose = verbose, overlord = overlord, blocking = true,
provers = provers, type_enc = type_enc, strict = strict,
lam_trans = lam_trans, uncurried_aliases = uncurried_aliases,
relevance_thresholds = (1.01, 1.01), max_relevant = SOME (length facts),
max_mono_iters = max_mono_iters,
max_new_mono_instances = max_new_mono_instances, isar_proof = isar_proof,
isar_shrink_factor = isar_shrink_factor, slice = false,
minimize = SOME false, timeout = timeout,
preplay_timeout = preplay_timeout, expect = ""}
val problem =
{state = state, goal = goal, subgoal = i, subgoal_count = n,
facts = facts}
val result as {outcome, used_facts, run_time, ...} =
prover params (K (K (K ""))) problem
in
print silent
(fn () =>
case outcome of
SOME failure => string_for_failure failure
| NONE =>
"Found proof" ^
(if length used_facts = length facts then ""
else " with " ^ n_facts used_facts) ^
" (" ^ string_from_time run_time ^ ").");
result
end
(* minimalization of facts *)
(* Give the external prover some slack. The ATP gets further slack because the
Sledgehammer preprocessing time is included in the estimate below but isn't
part of the timeout. *)
val slack_msecs = 200
fun new_timeout timeout run_time =
Int.min (Time.toMilliseconds timeout,
Time.toMilliseconds run_time + slack_msecs)
|> Time.fromMilliseconds
(* The linear algorithm usually outperforms the binary algorithm when over 60%
of the facts are actually needed. The binary algorithm is much more
appropriate for provers that cannot return the list of used facts and hence
returns all facts as used. Since we cannot know in advance how many facts are
actually needed, we heuristically set the threshold to 10 facts. *)
val binary_min_facts =
Attrib.setup_config_int @{binding sledgehammer_minimize_binary_min_facts}
(K 20)
val auto_minimize_min_facts =
Attrib.setup_config_int @{binding sledgehammer_auto_minimize_min_facts}
(fn generic => Config.get_generic generic binary_min_facts)
val auto_minimize_max_time =
Attrib.setup_config_real @{binding sledgehammer_auto_minimize_max_time}
(K 5.0)
fun linear_minimize test timeout result xs =
let
fun min _ [] p = p
| min timeout (x :: xs) (seen, result) =
case test timeout (xs @ seen) of
result as {outcome = NONE, used_facts, run_time, ...}
: prover_result =>
min (new_timeout timeout run_time) (filter_used_facts used_facts xs)
(filter_used_facts used_facts seen, result)
| _ => min timeout xs (x :: seen, result)
in min timeout xs ([], result) end
fun binary_minimize test timeout result xs =
let
fun min depth (result as {run_time, ...} : prover_result) sup
(xs as _ :: _ :: _) =
let
val (l0, r0) = chop (length xs div 2) xs
(*
val _ = warning (replicate_string depth " " ^ "{ " ^
"sup: " ^ n_facts (map fst sup))
val _ = warning (replicate_string depth " " ^ " " ^
"xs: " ^ n_facts (map fst xs))
val _ = warning (replicate_string depth " " ^ " " ^
"l0: " ^ n_facts (map fst l0))
val _ = warning (replicate_string depth " " ^ " " ^
"r0: " ^ n_facts (map fst r0))
*)
val depth = depth + 1
val timeout = new_timeout timeout run_time
in
case test timeout (sup @ l0) of
result as {outcome = NONE, used_facts, ...} =>
min depth result (filter_used_facts used_facts sup)
(filter_used_facts used_facts l0)
| _ =>
case test timeout (sup @ r0) of
result as {outcome = NONE, used_facts, ...} =>
min depth result (filter_used_facts used_facts sup)
(filter_used_facts used_facts r0)
| _ =>
let
val (sup_r0, (l, result)) = min depth result (sup @ r0) l0
val (sup, r0) =
(sup, r0) |> pairself (filter_used_facts (map fst sup_r0))
val (sup_l, (r, result)) = min depth result (sup @ l) r0
val sup = sup |> filter_used_facts (map fst sup_l)
in (sup, (l @ r, result)) end
end
(*
|> tap (fn _ => warning (replicate_string depth " " ^ "}"))
*)
| min _ result sup xs = (sup, (xs, result))
in
case snd (min 0 result [] xs) of
([x], result as {run_time, ...}) =>
(case test (new_timeout timeout run_time) [] of
result as {outcome = NONE, ...} => ([], result)
| _ => ([x], result))
| p => p
end
fun minimize_facts prover_name (params as {timeout, ...}) silent i n state
facts =
let
val ctxt = Proof.context_of state
val prover =
get_prover ctxt (if silent then Auto_Minimize else Minimize) prover_name
val _ = print silent (fn () => "Sledgehammer minimizer: " ^
quote prover_name ^ ".")
fun test timeout = test_facts params silent prover timeout i n state
in
(case test timeout facts of
result as {outcome = NONE, used_facts, run_time, ...} =>
let
val facts = filter_used_facts used_facts facts
val min =
if length facts >= Config.get ctxt binary_min_facts then
binary_minimize
else
linear_minimize
val (min_facts, {preplay, message, message_tail, ...}) =
min test (new_timeout timeout run_time) result facts
val _ = print silent (fn () => cat_lines
["Minimized to " ^ n_facts (map fst min_facts)] ^
(case min_facts |> filter (fn ((_, (sc, _)), _) => sc = Chained)
|> length of
0 => ""
| n => "\n(including " ^ string_of_int n ^ " chained)") ^ ".")
in (SOME min_facts, (preplay, message, message_tail)) end
| {outcome = SOME TimedOut, preplay, ...} =>
(NONE,
(preplay,
fn _ => "Timeout: You can increase the time limit using the \
\\"timeout\" option (e.g., \"timeout = " ^
string_of_int (10 + Time.toMilliseconds timeout div 1000) ^
"\").",
""))
| {preplay, message, ...} =>
(NONE, (preplay, prefix "Prover error: " o message, "")))
handle ERROR msg =>
(NONE, (K (Failed_to_Play plain_metis), fn _ => "Error: " ^ msg, ""))
end
fun adjust_reconstructor_params override_params
({debug, verbose, overlord, blocking, provers, type_enc, strict,
lam_trans, uncurried_aliases, relevance_thresholds, max_relevant,
max_mono_iters, max_new_mono_instances, isar_proof, isar_shrink_factor,
slice, minimize, timeout, preplay_timeout, expect} : params) =
let
fun lookup_override name default_value =
case AList.lookup (op =) override_params name of
SOME [s] => SOME s
| _ => default_value
(* Only those options that reconstructors are interested in are considered
here. *)
val type_enc = lookup_override "type_enc" type_enc
val lam_trans = lookup_override "lam_trans" lam_trans
in
{debug = debug, verbose = verbose, overlord = overlord, blocking = blocking,
provers = provers, type_enc = type_enc, strict = strict,
lam_trans = lam_trans, uncurried_aliases = uncurried_aliases,
max_relevant = max_relevant, relevance_thresholds = relevance_thresholds,
max_mono_iters = max_mono_iters,
max_new_mono_instances = max_new_mono_instances, isar_proof = isar_proof,
isar_shrink_factor = isar_shrink_factor, slice = slice,
minimize = minimize, timeout = timeout, preplay_timeout = preplay_timeout,
expect = expect}
end
fun minimize ctxt mode name
(params as {debug, verbose, isar_proof, minimize, ...})
({state, subgoal, subgoal_count, facts, ...} : prover_problem)
(result as {outcome, used_facts, run_time, preplay, message,
message_tail} : prover_result) =
if is_some outcome orelse null used_facts then
result
else
let
val num_facts = length used_facts
val ((perhaps_minimize, (minimize_name, params)), preplay) =
if mode = Normal then
if num_facts >= Config.get ctxt auto_minimize_min_facts then
((true, (name, params)), preplay)
else
let
fun can_min_fast_enough time =
0.001
* Real.fromInt ((num_facts + 1) * Time.toMilliseconds time)
<= Config.get ctxt auto_minimize_max_time
fun prover_fast_enough () = can_min_fast_enough run_time
in
if isar_proof then
((prover_fast_enough (), (name, params)), preplay)
else
let val preplay = preplay () in
(case preplay of
Played (reconstr, timeout) =>
if can_min_fast_enough timeout then
(true, extract_reconstructor params reconstr
||> (fn override_params =>
adjust_reconstructor_params
override_params params))
else
(prover_fast_enough (), (name, params))
| _ => (prover_fast_enough (), (name, params)),
K preplay)
end
end
else
((false, (name, params)), preplay)
val minimize = minimize |> the_default perhaps_minimize
val (used_facts, (preplay, message, _)) =
if minimize then
minimize_facts minimize_name params (not verbose) subgoal
subgoal_count state
(filter_used_facts used_facts
(map (apsnd single o untranslated_fact) facts))
|>> Option.map (map fst)
else
(SOME used_facts, (preplay, message, ""))
in
case used_facts of
SOME used_facts =>
(if debug andalso not (null used_facts) then
facts ~~ (0 upto length facts - 1)
|> map (fn (fact, j) => fact |> untranslated_fact |> apsnd (K j))
|> filter_used_facts used_facts
|> map (fn ((name, _), j) => name ^ "@" ^ string_of_int j)
|> commas
|> enclose ("Fact" ^ plural_s (length facts) ^ " in " ^ quote name ^
" proof (of " ^ string_of_int (length facts) ^ "): ") "."
|> Output.urgent_message
else
();
{outcome = NONE, used_facts = used_facts, run_time = run_time,
preplay = preplay, message = message, message_tail = message_tail})
| NONE => result
end
fun get_minimizing_prover ctxt mode name params minimize_command problem =
get_prover ctxt mode name params minimize_command problem
|> minimize ctxt mode name params problem
fun run_minimize (params as {provers, ...}) i refs state =
let
val ctxt = Proof.context_of state
val reserved = reserved_isar_keyword_table ()
val chained_ths = #facts (Proof.goal state)
val css_table = clasimpset_rule_table_of ctxt
val facts =
refs |> maps (map (apsnd single)
o fact_from_ref ctxt reserved chained_ths css_table)
in
case subgoal_count state of
0 => Output.urgent_message "No subgoal!"
| n => case provers of
[] => error "No prover is set."
| prover :: _ =>
(kill_provers ();
minimize_facts prover params false i n state facts
|> (fn (_, (preplay, message, message_tail)) =>
message (preplay ()) ^ message_tail
|> Output.urgent_message))
end
end;