src/HOL/Tools/SMT/z3_proof_reconstruction.ML
author boehmes
Tue Oct 26 11:49:23 2010 +0200 (2010-10-26)
changeset 40164 57f5db2a48a3
parent 40162 7f58a9a843c2
child 40274 6486c610a549
permissions -rw-r--r--
added a mode to only filter assumptions used in a Z3 proof (in which no proof reconstruction is performed)
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(*  Title:      HOL/Tools/SMT/z3_proof_reconstruction.ML
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    Author:     Sascha Boehme, TU Muenchen
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Proof reconstruction for proofs found by Z3.
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*)
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signature Z3_PROOF_RECONSTRUCTION =
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sig
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  val add_z3_rule: thm -> Context.generic -> Context.generic
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  val reconstruct: Proof.context -> SMT_Translate.recon -> string list ->
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    (int list * thm) * Proof.context
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  val setup: theory -> theory
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end
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structure Z3_Proof_Reconstruction: Z3_PROOF_RECONSTRUCTION =
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struct
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structure P = Z3_Proof_Parser
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structure T = Z3_Proof_Tools
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structure L = Z3_Proof_Literals
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fun z3_exn msg = raise SMT_Solver.SMT (SMT_Solver.Other_Failure
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  ("Z3 proof reconstruction: " ^ msg))
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(** net of schematic rules **)
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val z3_ruleN = "z3_rule"
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local
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  val description = "declaration of Z3 proof rules"
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  val eq = Thm.eq_thm
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  structure Z3_Rules = Generic_Data
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  (
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    type T = thm Net.net
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    val empty = Net.empty
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    val extend = I
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    val merge = Net.merge eq
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  )
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  val prep = `Thm.prop_of o Simplifier.rewrite_rule [L.rewrite_true]
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  fun ins thm net = Net.insert_term eq (prep thm) net handle Net.INSERT => net
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  fun del thm net = Net.delete_term eq (prep thm) net handle Net.DELETE => net
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  val add = Thm.declaration_attribute (Z3_Rules.map o ins)
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  val del = Thm.declaration_attribute (Z3_Rules.map o del)
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in
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val add_z3_rule = Z3_Rules.map o ins
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fun by_schematic_rule ctxt ct =
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  the (T.net_instance (Z3_Rules.get (Context.Proof ctxt)) ct)
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val z3_rules_setup =
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  Attrib.setup (Binding.name z3_ruleN) (Attrib.add_del add del) description #>
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  Global_Theory.add_thms_dynamic (Binding.name z3_ruleN, Net.content o Z3_Rules.get)
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end
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(** proof tools **)
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fun named ctxt name prover ct =
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  let val _ = SMT_Solver.trace_msg ctxt I ("Z3: trying " ^ name ^ " ...")
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  in prover ct end
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fun NAMED ctxt name tac i st =
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  let val _ = SMT_Solver.trace_msg ctxt I ("Z3: trying " ^ name ^ " ...")
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  in tac i st end
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fun pretty_goal ctxt thms t =
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  [Pretty.block [Pretty.str "proposition: ", Syntax.pretty_term ctxt t]]
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  |> not (null thms) ? cons (Pretty.big_list "assumptions:"
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       (map (Display.pretty_thm ctxt) thms))
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fun try_apply ctxt thms =
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  let
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    fun try_apply_err ct = Pretty.string_of (Pretty.chunks [
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      Pretty.big_list ("Z3 found a proof," ^
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        " but proof reconstruction failed at the following subgoal:")
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        (pretty_goal ctxt thms (Thm.term_of ct)),
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      Pretty.str ("Adding a rule to the lemma group " ^ quote z3_ruleN ^
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        " might solve this problem.")])
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    fun apply [] ct = error (try_apply_err ct)
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      | apply (prover :: provers) ct =
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          (case try prover ct of
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            SOME thm => (SMT_Solver.trace_msg ctxt I "Z3: succeeded"; thm)
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          | NONE => apply provers ct)
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  in apply o cons (named ctxt "schematic rules" (by_schematic_rule ctxt)) end
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local
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  val rewr_if =
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    @{lemma "(if P then Q1 else Q2) = ((P --> Q1) & (~P --> Q2))" by simp}
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in
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val simp_fast_tac =
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  Simplifier.simp_tac (HOL_ss addsimps [rewr_if])
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  THEN_ALL_NEW Classical.fast_tac HOL_cs
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end
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(** theorems and proofs **)
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(* theorem incarnations *)
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datatype theorem =
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  Thm of thm | (* theorem without special features *)
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  MetaEq of thm | (* meta equality "t == s" *)
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  Literals of thm * L.littab
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    (* "P1 & ... & Pn" and table of all literals P1, ..., Pn *)
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fun thm_of (Thm thm) = thm
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  | thm_of (MetaEq thm) = thm COMP @{thm meta_eq_to_obj_eq}
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  | thm_of (Literals (thm, _)) = thm
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fun meta_eq_of (MetaEq thm) = thm
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  | meta_eq_of p = mk_meta_eq (thm_of p)
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fun literals_of (Literals (_, lits)) = lits
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  | literals_of p = L.make_littab [thm_of p]
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(* proof representation *)
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datatype proof = Unproved of P.proof_step | Proved of theorem
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(** core proof rules **)
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(* assumption *)
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local
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  val remove_trigger = @{lemma "trigger t p == p"
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    by (rule eq_reflection, rule trigger_def)}
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  val prep_rules = [@{thm Let_def}, remove_trigger, L.rewrite_true]
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  fun rewrite_conv ctxt eqs = Simplifier.full_rewrite
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    (Simplifier.context ctxt Simplifier.empty_ss addsimps eqs)
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  fun rewrites f ctxt eqs = map (f (Conv.fconv_rule (rewrite_conv ctxt eqs)))
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  fun burrow_snd_option f (i, thm) = Option.map (pair i) (f thm)
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  fun lookup_assm ctxt assms ct =
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    (case T.net_instance' burrow_snd_option assms ct of
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      SOME ithm => ithm
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    | _ => z3_exn ("not asserted: " ^
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        quote (Syntax.string_of_term ctxt (Thm.term_of ct))))
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in
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fun prepare_assms ctxt unfolds assms =
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  let
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    val unfolds' = rewrites I ctxt [L.rewrite_true] unfolds
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    val assms' =
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      rewrites apsnd ctxt (union Thm.eq_thm unfolds' prep_rules) assms
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  in (unfolds', T.thm_net_of snd assms') end
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fun asserted ctxt (unfolds, assms) ct =
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  let val revert_conv = rewrite_conv ctxt unfolds
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  in Thm (T.with_conv revert_conv (snd o lookup_assm ctxt assms) ct) end
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fun find_assm ctxt (unfolds, assms) ct =
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  fst (lookup_assm ctxt assms (Thm.rhs_of (rewrite_conv ctxt unfolds ct)))
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end
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(* P = Q ==> P ==> Q   or   P --> Q ==> P ==> Q *)
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local
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  val meta_iffD1 = @{lemma "P == Q ==> P ==> (Q::bool)" by simp}
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  val meta_iffD1_c = T.precompose2 Thm.dest_binop meta_iffD1
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  val iffD1_c = T.precompose2 (Thm.dest_binop o Thm.dest_arg) @{thm iffD1}
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  val mp_c = T.precompose2 (Thm.dest_binop o Thm.dest_arg) @{thm mp}
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in
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fun mp (MetaEq thm) p = Thm (Thm.implies_elim (T.compose meta_iffD1_c thm) p)
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  | mp p_q p = 
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      let
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        val pq = thm_of p_q
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        val thm = T.compose iffD1_c pq handle THM _ => T.compose mp_c pq
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      in Thm (Thm.implies_elim thm p) end
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end
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(* and_elim:     P1 & ... & Pn ==> Pi *)
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(* not_or_elim:  ~(P1 | ... | Pn) ==> ~Pi *)
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local
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  fun is_sublit conj t = L.exists_lit conj (fn u => u aconv t)
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  fun derive conj t lits idx ptab =
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    let
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      val lit = the (L.get_first_lit (is_sublit conj t) lits)
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      val ls = L.explode conj false false [t] lit
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      val lits' = fold L.insert_lit ls (L.delete_lit lit lits)
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      fun upd (Proved thm) = Proved (Literals (thm_of thm, lits'))
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        | upd p = p
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    in (the (L.lookup_lit lits' t), Inttab.map_entry idx upd ptab) end
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  fun lit_elim conj (p, idx) ct ptab =
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    let val lits = literals_of p
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    in
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      (case L.lookup_lit lits (T.term_of ct) of
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        SOME lit => (Thm lit, ptab)
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      | NONE => apfst Thm (derive conj (T.term_of ct) lits idx ptab))
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    end
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in
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val and_elim = lit_elim true
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val not_or_elim = lit_elim false
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end
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(* P1, ..., Pn |- False ==> |- ~P1 | ... | ~Pn *)
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local
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  fun step lit thm =
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    Thm.implies_elim (Thm.implies_intr (Thm.cprop_of lit) thm) lit
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  val explode_disj = L.explode false false false
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  fun intro hyps thm th = fold step (explode_disj hyps th) thm
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  fun dest_ccontr ct = [Thm.dest_arg (Thm.dest_arg (Thm.dest_arg1 ct))]
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  val ccontr = T.precompose dest_ccontr @{thm ccontr}
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in
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fun lemma thm ct =
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  let
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    val cu = Thm.capply @{cterm Not} (Thm.dest_arg ct)
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    val hyps = map_filter (try HOLogic.dest_Trueprop) (#hyps (Thm.rep_thm thm))
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  in Thm (T.compose ccontr (T.under_assumption (intro hyps thm) cu)) end
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end
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(* \/{P1, ..., Pn, Q1, ..., Qn}, ~P1, ..., ~Pn ==> \/{Q1, ..., Qn} *)
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local
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  val explode_disj = L.explode false true false
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  val join_disj = L.join false
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  fun unit thm thms th =
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    let val t = @{term Not} $ T.prop_of thm and ts = map T.prop_of thms
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    in join_disj (L.make_littab (thms @ explode_disj ts th)) t end
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  fun dest_arg2 ct = Thm.dest_arg (Thm.dest_arg ct)
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  fun dest ct = pairself dest_arg2 (Thm.dest_binop ct)
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  val contrapos = T.precompose2 dest @{lemma "(~P ==> ~Q) ==> Q ==> P" by fast}
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in
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fun unit_resolution thm thms ct =
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  Thm.capply @{cterm Not} (Thm.dest_arg ct)
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  |> T.under_assumption (unit thm thms)
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  |> Thm o T.discharge thm o T.compose contrapos
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end
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(* P ==> P == True   or   P ==> P == False *)
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local
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  val iff1 = @{lemma "P ==> P == (~ False)" by simp}
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  val iff2 = @{lemma "~P ==> P == False" by simp}
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in
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fun iff_true thm = MetaEq (thm COMP iff1)
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fun iff_false thm = MetaEq (thm COMP iff2)
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end
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(* distributivity of | over & *)
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fun distributivity ctxt = Thm o try_apply ctxt [] [
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  named ctxt "fast" (T.by_tac (Classical.fast_tac HOL_cs))]
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    (* FIXME: not very well tested *)
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(* Tseitin-like axioms *)
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local
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  val disjI1 = @{lemma "(P ==> Q) ==> ~P | Q" by fast}
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  val disjI2 = @{lemma "(~P ==> Q) ==> P | Q" by fast}
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  val disjI3 = @{lemma "(~Q ==> P) ==> P | Q" by fast}
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  val disjI4 = @{lemma "(Q ==> P) ==> P | ~Q" by fast}
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  fun prove' conj1 conj2 ct2 thm =
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    let val lits = L.true_thm :: L.explode conj1 true (conj1 <> conj2) [] thm
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    in L.join conj2 (L.make_littab lits) (Thm.term_of ct2) end
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  fun prove rule (ct1, conj1) (ct2, conj2) =
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    T.under_assumption (prove' conj1 conj2 ct2) ct1 COMP rule
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  fun prove_def_axiom ct =
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    let val (ct1, ct2) = Thm.dest_binop (Thm.dest_arg ct)
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    in
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      (case Thm.term_of ct1 of
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        @{term Not} $ (@{term HOL.conj} $ _ $ _) =>
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          prove disjI1 (Thm.dest_arg ct1, true) (ct2, true)
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      | @{term HOL.conj} $ _ $ _ =>
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          prove disjI3 (Thm.capply @{cterm Not} ct2, false) (ct1, true)
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      | @{term Not} $ (@{term HOL.disj} $ _ $ _) =>
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          prove disjI3 (Thm.capply @{cterm Not} ct2, false) (ct1, false)
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      | @{term HOL.disj} $ _ $ _ =>
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          prove disjI2 (Thm.capply @{cterm Not} ct1, false) (ct2, true)
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      | Const (@{const_name distinct}, _) $ _ =>
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          let
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            fun dis_conv cv = Conv.arg_conv (Conv.arg1_conv cv)
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            fun prv cu =
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              let val (cu1, cu2) = Thm.dest_binop (Thm.dest_arg cu)
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              in prove disjI4 (Thm.dest_arg cu2, true) (cu1, true) end
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          in T.with_conv (dis_conv T.unfold_distinct_conv) prv ct end
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      | @{term Not} $ (Const (@{const_name distinct}, _) $ _) =>
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          let
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            fun dis_conv cv = Conv.arg_conv (Conv.arg1_conv (Conv.arg_conv cv))
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            fun prv cu =
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              let val (cu1, cu2) = Thm.dest_binop (Thm.dest_arg cu)
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              in prove disjI1 (Thm.dest_arg cu1, true) (cu2, true) end
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          in T.with_conv (dis_conv T.unfold_distinct_conv) prv ct end
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      | _ => raise CTERM ("prove_def_axiom", [ct]))
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    end
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in
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fun def_axiom ctxt = Thm o try_apply ctxt [] [
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  named ctxt "conj/disj/distinct" prove_def_axiom,
boehmes@36899
   325
  T.by_abstraction (true, false) ctxt [] (fn ctxt' =>
boehmes@36899
   326
    named ctxt' "simp+fast" (T.by_tac simp_fast_tac))]
boehmes@36898
   327
end
boehmes@36898
   328
boehmes@36898
   329
boehmes@36898
   330
boehmes@36898
   331
(* local definitions *)
boehmes@36898
   332
local
boehmes@36898
   333
  val intro_rules = [
boehmes@36898
   334
    @{lemma "n == P ==> (~n | P) & (n | ~P)" by simp},
boehmes@36898
   335
    @{lemma "n == (if P then s else t) ==> (~P | n = s) & (P | n = t)"
boehmes@36898
   336
      by simp},
boehmes@36898
   337
    @{lemma "n == P ==> n = P" by (rule meta_eq_to_obj_eq)} ]
boehmes@36898
   338
boehmes@36898
   339
  val apply_rules = [
boehmes@36898
   340
    @{lemma "(~n | P) & (n | ~P) ==> P == n" by (atomize(full)) fast},
boehmes@36898
   341
    @{lemma "(~P | n = s) & (P | n = t) ==> (if P then s else t) == n"
boehmes@36898
   342
      by (atomize(full)) fastsimp} ]
boehmes@36898
   343
boehmes@36898
   344
  val inst_rule = T.match_instantiate Thm.dest_arg
boehmes@36898
   345
boehmes@36898
   346
  fun apply_rule ct =
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   347
    (case get_first (try (inst_rule ct)) intro_rules of
boehmes@36898
   348
      SOME thm => thm
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   349
    | NONE => raise CTERM ("intro_def", [ct]))
boehmes@36898
   350
in
boehmes@36898
   351
fun intro_def ct = T.make_hyp_def (apply_rule ct) #>> Thm
boehmes@36898
   352
boehmes@36898
   353
fun apply_def thm =
boehmes@36898
   354
  get_first (try (fn rule => MetaEq (thm COMP rule))) apply_rules
boehmes@36898
   355
  |> the_default (Thm thm)
boehmes@36898
   356
end
boehmes@36898
   357
boehmes@36898
   358
boehmes@36898
   359
boehmes@36898
   360
(* negation normal form *)
boehmes@36898
   361
boehmes@36898
   362
local
boehmes@36898
   363
  val quant_rules1 = ([
boehmes@36898
   364
    @{lemma "(!!x. P x == Q) ==> ALL x. P x == Q" by simp},
boehmes@36898
   365
    @{lemma "(!!x. P x == Q) ==> EX x. P x == Q" by simp}], [
boehmes@36898
   366
    @{lemma "(!!x. P x == Q x) ==> ALL x. P x == ALL x. Q x" by simp},
boehmes@36898
   367
    @{lemma "(!!x. P x == Q x) ==> EX x. P x == EX x. Q x" by simp}])
boehmes@36898
   368
boehmes@36898
   369
  val quant_rules2 = ([
boehmes@36898
   370
    @{lemma "(!!x. ~P x == Q) ==> ~(ALL x. P x) == Q" by simp},
boehmes@36898
   371
    @{lemma "(!!x. ~P x == Q) ==> ~(EX x. P x) == Q" by simp}], [
boehmes@36898
   372
    @{lemma "(!!x. ~P x == Q x) ==> ~(ALL x. P x) == EX x. Q x" by simp},
boehmes@36898
   373
    @{lemma "(!!x. ~P x == Q x) ==> ~(EX x. P x) == ALL x. Q x" by simp}])
boehmes@36898
   374
boehmes@36898
   375
  fun nnf_quant_tac thm (qs as (qs1, qs2)) i st = (
boehmes@36898
   376
    Tactic.rtac thm ORELSE'
boehmes@36898
   377
    (Tactic.match_tac qs1 THEN' nnf_quant_tac thm qs) ORELSE'
boehmes@36898
   378
    (Tactic.match_tac qs2 THEN' nnf_quant_tac thm qs)) i st
boehmes@36898
   379
boehmes@36898
   380
  fun nnf_quant vars qs p ct =
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   381
    T.as_meta_eq ct
boehmes@36898
   382
    |> T.by_tac (nnf_quant_tac (T.varify vars (meta_eq_of p)) qs)
boehmes@36898
   383
boehmes@36898
   384
  fun prove_nnf ctxt = try_apply ctxt [] [
boehmes@36899
   385
    named ctxt "conj/disj" L.prove_conj_disj_eq,
boehmes@36899
   386
    T.by_abstraction (true, false) ctxt [] (fn ctxt' =>
boehmes@36899
   387
      named ctxt' "simp+fast" (T.by_tac simp_fast_tac))]
boehmes@36898
   388
in
boehmes@36898
   389
fun nnf ctxt vars ps ct =
boehmes@36898
   390
  (case T.term_of ct of
boehmes@36898
   391
    _ $ (l as Const _ $ Abs _) $ (r as Const _ $ Abs _) =>
boehmes@36898
   392
      if l aconv r
boehmes@36898
   393
      then MetaEq (Thm.reflexive (Thm.dest_arg (Thm.dest_arg ct)))
boehmes@36898
   394
      else MetaEq (nnf_quant vars quant_rules1 (hd ps) ct)
boehmes@36898
   395
  | _ $ (@{term Not} $ (Const _ $ Abs _)) $ (Const _ $ Abs _) =>
boehmes@36898
   396
      MetaEq (nnf_quant vars quant_rules2 (hd ps) ct)
boehmes@36898
   397
  | _ =>
boehmes@36898
   398
      let
boehmes@36898
   399
        val nnf_rewr_conv = Conv.arg_conv (Conv.arg_conv
boehmes@36898
   400
          (T.unfold_eqs ctxt (map (Thm.symmetric o meta_eq_of) ps)))
boehmes@36898
   401
      in Thm (T.with_conv nnf_rewr_conv (prove_nnf ctxt) ct) end)
boehmes@36898
   402
end
boehmes@36898
   403
boehmes@36898
   404
boehmes@36898
   405
boehmes@36898
   406
(** equality proof rules **)
boehmes@36898
   407
boehmes@36898
   408
(* |- t = t *)
boehmes@36898
   409
fun refl ct = MetaEq (Thm.reflexive (Thm.dest_arg (Thm.dest_arg ct)))
boehmes@36898
   410
boehmes@36898
   411
boehmes@36898
   412
boehmes@36898
   413
(* s = t ==> t = s *)
boehmes@36898
   414
local
boehmes@36898
   415
  val symm_rule = @{lemma "s = t ==> t == s" by simp}
boehmes@36898
   416
in
boehmes@36898
   417
fun symm (MetaEq thm) = MetaEq (Thm.symmetric thm)
boehmes@36898
   418
  | symm p = MetaEq (thm_of p COMP symm_rule)
boehmes@36898
   419
end
boehmes@36898
   420
boehmes@36898
   421
boehmes@36898
   422
boehmes@36898
   423
(* s = t ==> t = u ==> s = u *)
boehmes@36898
   424
local
boehmes@36898
   425
  val trans1 = @{lemma "s == t ==> t =  u ==> s == u" by simp}
boehmes@36898
   426
  val trans2 = @{lemma "s =  t ==> t == u ==> s == u" by simp}
boehmes@36898
   427
  val trans3 = @{lemma "s =  t ==> t =  u ==> s == u" by simp}
boehmes@36898
   428
in
boehmes@36898
   429
fun trans (MetaEq thm1) (MetaEq thm2) = MetaEq (Thm.transitive thm1 thm2)
boehmes@36898
   430
  | trans (MetaEq thm) q = MetaEq (thm_of q COMP (thm COMP trans1))
boehmes@36898
   431
  | trans p (MetaEq thm) = MetaEq (thm COMP (thm_of p COMP trans2))
boehmes@36898
   432
  | trans p q = MetaEq (thm_of q COMP (thm_of p COMP trans3))
boehmes@36898
   433
end
boehmes@36898
   434
boehmes@36898
   435
boehmes@36898
   436
boehmes@36898
   437
(* t1 = s1 ==> ... ==> tn = sn ==> f t1 ... tn = f s1 .. sn
boehmes@36898
   438
   (reflexive antecendents are droppped) *)
boehmes@36898
   439
local
boehmes@36898
   440
  exception MONO
boehmes@36898
   441
boehmes@36898
   442
  fun prove_refl (ct, _) = Thm.reflexive ct
boehmes@36898
   443
  fun prove_comb f g cp =
boehmes@36898
   444
    let val ((ct1, ct2), (cu1, cu2)) = pairself Thm.dest_comb cp
boehmes@36898
   445
    in Thm.combination (f (ct1, cu1)) (g (ct2, cu2)) end
boehmes@36898
   446
  fun prove_arg f = prove_comb prove_refl f
boehmes@36898
   447
boehmes@36898
   448
  fun prove f cp = prove_comb (prove f) f cp handle CTERM _ => prove_refl cp
boehmes@36898
   449
boehmes@36898
   450
  fun prove_nary is_comb f =
boehmes@36898
   451
    let
boehmes@36898
   452
      fun prove (cp as (ct, _)) = f cp handle MONO =>
boehmes@36898
   453
        if is_comb (Thm.term_of ct)
boehmes@36898
   454
        then prove_comb (prove_arg prove) prove cp
boehmes@36898
   455
        else prove_refl cp
boehmes@36898
   456
    in prove end
boehmes@36898
   457
boehmes@36898
   458
  fun prove_list f n cp =
boehmes@36898
   459
    if n = 0 then prove_refl cp
boehmes@36898
   460
    else prove_comb (prove_arg f) (prove_list f (n-1)) cp
boehmes@36898
   461
boehmes@36898
   462
  fun with_length f (cp as (cl, _)) =
boehmes@36898
   463
    f (length (HOLogic.dest_list (Thm.term_of cl))) cp
boehmes@36898
   464
boehmes@36898
   465
  fun prove_distinct f = prove_arg (with_length (prove_list f))
boehmes@36898
   466
boehmes@36898
   467
  fun prove_eq exn lookup cp =
boehmes@36898
   468
    (case lookup (Logic.mk_equals (pairself Thm.term_of cp)) of
boehmes@36898
   469
      SOME eq => eq
boehmes@36898
   470
    | NONE => if exn then raise MONO else prove_refl cp)
boehmes@36898
   471
  
boehmes@36898
   472
  val prove_eq_exn = prove_eq true
boehmes@36898
   473
  and prove_eq_safe = prove_eq false
boehmes@36898
   474
boehmes@36898
   475
  fun mono f (cp as (cl, _)) =
boehmes@36898
   476
    (case Term.head_of (Thm.term_of cl) of
haftmann@38795
   477
      @{term HOL.conj} => prove_nary L.is_conj (prove_eq_exn f)
haftmann@38795
   478
    | @{term HOL.disj} => prove_nary L.is_disj (prove_eq_exn f)
boehmes@36898
   479
    | Const (@{const_name distinct}, _) => prove_distinct (prove_eq_safe f)
boehmes@36898
   480
    | _ => prove (prove_eq_safe f)) cp
boehmes@36898
   481
in
boehmes@36898
   482
fun monotonicity eqs ct =
boehmes@36898
   483
  let
boehmes@36898
   484
    val lookup = AList.lookup (op aconv) (map (`Thm.prop_of o meta_eq_of) eqs)
boehmes@36898
   485
    val cp = Thm.dest_binop (Thm.dest_arg ct)
boehmes@36898
   486
  in MetaEq (prove_eq_exn lookup cp handle MONO => mono lookup cp) end
boehmes@36898
   487
end
boehmes@36898
   488
boehmes@36898
   489
boehmes@36898
   490
boehmes@36898
   491
(* |- f a b = f b a (where f is equality) *)
boehmes@36898
   492
local
boehmes@36898
   493
  val rule = @{lemma "a = b == b = a" by (atomize(full)) (rule eq_commute)}
boehmes@36898
   494
in
boehmes@36898
   495
fun commutativity ct = MetaEq (T.match_instantiate I (T.as_meta_eq ct) rule)
boehmes@36898
   496
end
boehmes@36898
   497
boehmes@36898
   498
boehmes@36898
   499
boehmes@36898
   500
(** quantifier proof rules **)
boehmes@36898
   501
boehmes@36898
   502
(* P ?x = Q ?x ==> (ALL x. P x) = (ALL x. Q x)
boehmes@36898
   503
   P ?x = Q ?x ==> (EX x. P x) = (EX x. Q x)    *)
boehmes@36898
   504
local
boehmes@36898
   505
  val rules = [
boehmes@36898
   506
    @{lemma "(!!x. P x == Q x) ==> (ALL x. P x) == (ALL x. Q x)" by simp},
boehmes@36898
   507
    @{lemma "(!!x. P x == Q x) ==> (EX x. P x) == (EX x. Q x)" by simp}]
boehmes@36898
   508
in
boehmes@36898
   509
fun quant_intro vars p ct =
boehmes@36898
   510
  let
boehmes@36898
   511
    val thm = meta_eq_of p
boehmes@36898
   512
    val rules' = T.varify vars thm :: rules
boehmes@36898
   513
    val cu = T.as_meta_eq ct
boehmes@36898
   514
  in MetaEq (T.by_tac (REPEAT_ALL_NEW (Tactic.match_tac rules')) cu) end
boehmes@36898
   515
end
boehmes@36898
   516
boehmes@36898
   517
boehmes@36898
   518
boehmes@36898
   519
(* |- ((ALL x. P x) | Q) = (ALL x. P x | Q) *)
boehmes@36898
   520
fun pull_quant ctxt = Thm o try_apply ctxt [] [
boehmes@36898
   521
  named ctxt "fast" (T.by_tac (Classical.fast_tac HOL_cs))]
boehmes@36898
   522
    (* FIXME: not very well tested *)
boehmes@36898
   523
boehmes@36898
   524
boehmes@36898
   525
boehmes@36898
   526
(* |- (ALL x. P x & Q x) = ((ALL x. P x) & (ALL x. Q x)) *)
boehmes@36898
   527
fun push_quant ctxt = Thm o try_apply ctxt [] [
boehmes@36898
   528
  named ctxt "fast" (T.by_tac (Classical.fast_tac HOL_cs))]
boehmes@36898
   529
    (* FIXME: not very well tested *)
boehmes@36898
   530
boehmes@36898
   531
boehmes@36898
   532
boehmes@36898
   533
(* |- (ALL x1 ... xn y1 ... yn. P x1 ... xn) = (ALL x1 ... xn. P x1 ... xn) *)
boehmes@36898
   534
local
boehmes@36898
   535
  val elim_all = @{lemma "(ALL x. P) == P" by simp}
boehmes@36898
   536
  val elim_ex = @{lemma "(EX x. P) == P" by simp}
boehmes@36898
   537
boehmes@36898
   538
  fun elim_unused_conv ctxt =
boehmes@36898
   539
    Conv.params_conv ~1 (K (Conv.arg_conv (Conv.arg1_conv
wenzelm@36936
   540
      (Conv.rewrs_conv [elim_all, elim_ex])))) ctxt
boehmes@36898
   541
boehmes@36898
   542
  fun elim_unused_tac ctxt =
boehmes@36898
   543
    REPEAT_ALL_NEW (
boehmes@36898
   544
      Tactic.match_tac [@{thm refl}, @{thm iff_allI}, @{thm iff_exI}]
boehmes@36898
   545
      ORELSE' CONVERSION (elim_unused_conv ctxt))
boehmes@36898
   546
in
boehmes@36898
   547
fun elim_unused_vars ctxt = Thm o T.by_tac (elim_unused_tac ctxt)
boehmes@36898
   548
end
boehmes@36898
   549
boehmes@36898
   550
boehmes@36898
   551
boehmes@36898
   552
(* |- (ALL x1 ... xn. ~(x1 = t1 & ... xn = tn) | P x1 ... xn) = P t1 ... tn *)
boehmes@36898
   553
fun dest_eq_res ctxt = Thm o try_apply ctxt [] [
boehmes@36898
   554
  named ctxt "fast" (T.by_tac (Classical.fast_tac HOL_cs))]
boehmes@36898
   555
    (* FIXME: not very well tested *)
boehmes@36898
   556
boehmes@36898
   557
boehmes@36898
   558
boehmes@36898
   559
(* |- ~(ALL x1...xn. P x1...xn) | P a1...an *)
boehmes@36898
   560
local
boehmes@36898
   561
  val rule = @{lemma "~ P x | Q ==> ~(ALL x. P x) | Q" by fast}
boehmes@36898
   562
in
boehmes@36898
   563
val quant_inst = Thm o T.by_tac (
boehmes@36898
   564
  REPEAT_ALL_NEW (Tactic.match_tac [rule])
boehmes@36898
   565
  THEN' Tactic.rtac @{thm excluded_middle})
boehmes@36898
   566
end
boehmes@36898
   567
boehmes@36898
   568
boehmes@36898
   569
boehmes@36898
   570
(* c = SOME x. P x |- (EX x. P x) = P c
boehmes@36898
   571
   c = SOME x. ~ P x |- ~(ALL x. P x) = ~ P c *)
boehmes@36898
   572
local
boehmes@36898
   573
  val elim_ex = @{lemma "EX x. P == P" by simp}
boehmes@36898
   574
  val elim_all = @{lemma "~ (ALL x. P) == ~P" by simp}
boehmes@36898
   575
  val sk_ex = @{lemma "c == SOME x. P x ==> EX x. P x == P c"
boehmes@36898
   576
    by simp (intro eq_reflection some_eq_ex[symmetric])}
boehmes@36898
   577
  val sk_all = @{lemma "c == SOME x. ~ P x ==> ~(ALL x. P x) == ~ P c"
boehmes@36898
   578
    by (simp only: not_all) (intro eq_reflection some_eq_ex[symmetric])}
boehmes@36898
   579
  val sk_ex_rule = ((sk_ex, I), elim_ex)
boehmes@36898
   580
  and sk_all_rule = ((sk_all, Thm.dest_arg), elim_all)
boehmes@36898
   581
boehmes@36898
   582
  fun dest f sk_rule = 
boehmes@36898
   583
    Thm.dest_comb (f (Thm.dest_arg (Thm.dest_arg (Thm.cprop_of sk_rule))))
boehmes@36898
   584
  fun type_of f sk_rule = Thm.ctyp_of_term (snd (dest f sk_rule))
boehmes@36898
   585
  fun pair2 (a, b) (c, d) = [(a, c), (b, d)]
boehmes@36898
   586
  fun inst_sk (sk_rule, f) p c =
boehmes@36898
   587
    Thm.instantiate ([(type_of f sk_rule, Thm.ctyp_of_term c)], []) sk_rule
boehmes@36898
   588
    |> (fn sk' => Thm.instantiate ([], (pair2 (dest f sk') (p, c))) sk')
boehmes@36898
   589
    |> Conv.fconv_rule (Thm.beta_conversion true)
boehmes@36898
   590
boehmes@36898
   591
  fun kind (Const (@{const_name Ex}, _) $ _) = (sk_ex_rule, I, I)
boehmes@36898
   592
    | kind (@{term Not} $ (Const (@{const_name All}, _) $ _)) =
boehmes@36898
   593
        (sk_all_rule, Thm.dest_arg, Thm.capply @{cterm Not})
boehmes@36898
   594
    | kind t = raise TERM ("skolemize", [t])
boehmes@36898
   595
boehmes@36898
   596
  fun dest_abs_type (Abs (_, T, _)) = T
boehmes@36898
   597
    | dest_abs_type t = raise TERM ("dest_abs_type", [t])
boehmes@36898
   598
boehmes@36898
   599
  fun bodies_of thy lhs rhs =
boehmes@36898
   600
    let
boehmes@36898
   601
      val (rule, dest, make) = kind (Thm.term_of lhs)
boehmes@36898
   602
boehmes@36898
   603
      fun dest_body idx cbs ct =
boehmes@36898
   604
        let
boehmes@36898
   605
          val cb = Thm.dest_arg (dest ct)
boehmes@36898
   606
          val T = dest_abs_type (Thm.term_of cb)
boehmes@36898
   607
          val cv = Thm.cterm_of thy (Var (("x", idx), T))
boehmes@36898
   608
          val cu = make (Drule.beta_conv cb cv)
boehmes@36898
   609
          val cbs' = (cv, cb) :: cbs
boehmes@36898
   610
        in
boehmes@36898
   611
          (snd (Thm.first_order_match (cu, rhs)), rev cbs')
boehmes@36898
   612
          handle Pattern.MATCH => dest_body (idx+1) cbs' cu
boehmes@36898
   613
        end
boehmes@36898
   614
    in (rule, dest_body 1 [] lhs) end
boehmes@36898
   615
boehmes@36898
   616
  fun transitive f thm = Thm.transitive thm (f (Thm.rhs_of thm))
boehmes@36898
   617
boehmes@36898
   618
  fun sk_step (rule, elim) (cv, mct, cb) ((is, thm), ctxt) =
boehmes@36898
   619
    (case mct of
boehmes@36898
   620
      SOME ct =>
boehmes@36898
   621
        ctxt
boehmes@36898
   622
        |> T.make_hyp_def (inst_sk rule (Thm.instantiate_cterm ([], is) cb) ct)
boehmes@36898
   623
        |>> pair ((cv, ct) :: is) o Thm.transitive thm
boehmes@36898
   624
    | NONE => ((is, transitive (Conv.rewr_conv elim) thm), ctxt))
boehmes@36898
   625
in
boehmes@36898
   626
fun skolemize ct ctxt =
boehmes@36898
   627
  let
boehmes@36898
   628
    val (lhs, rhs) = Thm.dest_binop (Thm.dest_arg ct)
boehmes@36898
   629
    val (rule, (ctab, cbs)) = bodies_of (ProofContext.theory_of ctxt) lhs rhs
boehmes@36898
   630
    fun lookup_var (cv, cb) = (cv, AList.lookup (op aconvc) ctab cv, cb)
boehmes@36898
   631
  in
boehmes@36898
   632
    (([], Thm.reflexive lhs), ctxt)
boehmes@36898
   633
    |> fold (sk_step rule) (map lookup_var cbs)
boehmes@36898
   634
    |>> MetaEq o snd
boehmes@36898
   635
  end
boehmes@36898
   636
end
boehmes@36898
   637
boehmes@36898
   638
boehmes@36898
   639
boehmes@36898
   640
(** theory proof rules **)
boehmes@36898
   641
boehmes@36898
   642
(* theory lemmas: linear arithmetic, arrays *)
boehmes@36898
   643
boehmes@36898
   644
fun th_lemma ctxt simpset thms = Thm o try_apply ctxt thms [
boehmes@36899
   645
  T.by_abstraction (false, true) ctxt thms (fn ctxt' => T.by_tac (
boehmes@36898
   646
    NAMED ctxt' "arith" (Arith_Data.arith_tac ctxt')
boehmes@36898
   647
    ORELSE' NAMED ctxt' "simp+arith" (Simplifier.simp_tac simpset THEN_ALL_NEW
boehmes@36898
   648
      Arith_Data.arith_tac ctxt')))]
boehmes@36898
   649
boehmes@36898
   650
boehmes@36898
   651
boehmes@36898
   652
(* rewriting: prove equalities:
boehmes@36898
   653
     * ACI of conjunction/disjunction
boehmes@36898
   654
     * contradiction, excluded middle
boehmes@36898
   655
     * logical rewriting rules (for negation, implication, equivalence,
boehmes@36898
   656
         distinct)
boehmes@36898
   657
     * normal forms for polynoms (integer/real arithmetic)
boehmes@36898
   658
     * quantifier elimination over linear arithmetic
boehmes@36898
   659
     * ... ? **)
boehmes@36898
   660
structure Z3_Simps = Named_Thms
boehmes@36898
   661
(
boehmes@36898
   662
  val name = "z3_simp"
boehmes@36898
   663
  val description = "simplification rules for Z3 proof reconstruction"
boehmes@36898
   664
)
boehmes@36898
   665
boehmes@36898
   666
local
boehmes@36898
   667
  fun spec_meta_eq_of thm =
boehmes@36898
   668
    (case try (fn th => th RS @{thm spec}) thm of
boehmes@36898
   669
      SOME thm' => spec_meta_eq_of thm'
boehmes@36898
   670
    | NONE => mk_meta_eq thm)
boehmes@36898
   671
boehmes@36898
   672
  fun prep (Thm thm) = spec_meta_eq_of thm
boehmes@36898
   673
    | prep (MetaEq thm) = thm
boehmes@36898
   674
    | prep (Literals (thm, _)) = spec_meta_eq_of thm
boehmes@36898
   675
boehmes@36898
   676
  fun unfold_conv ctxt ths =
boehmes@36898
   677
    Conv.arg_conv (Conv.binop_conv (T.unfold_eqs ctxt (map prep ths)))
boehmes@36898
   678
boehmes@36898
   679
  fun with_conv _ [] prv = prv
boehmes@36898
   680
    | with_conv ctxt ths prv = T.with_conv (unfold_conv ctxt ths) prv
boehmes@36898
   681
boehmes@36898
   682
  val unfold_conv =
boehmes@36898
   683
    Conv.arg_conv (Conv.binop_conv (Conv.try_conv T.unfold_distinct_conv))
boehmes@36898
   684
  val prove_conj_disj_eq = T.with_conv unfold_conv L.prove_conj_disj_eq
boehmes@36898
   685
in
boehmes@36898
   686
boehmes@36898
   687
fun rewrite ctxt simpset ths = Thm o with_conv ctxt ths (try_apply ctxt [] [
boehmes@36898
   688
  named ctxt "conj/disj/distinct" prove_conj_disj_eq,
boehmes@37126
   689
  T.by_abstraction (true, false) ctxt [] (fn ctxt' => T.by_tac (
boehmes@37126
   690
    NAMED ctxt' "simp (logic)" (Simplifier.simp_tac simpset)
boehmes@37126
   691
    THEN_ALL_NEW NAMED ctxt' "fast (logic)" (Classical.fast_tac HOL_cs))),
boehmes@37126
   692
  T.by_abstraction (false, true) ctxt [] (fn ctxt' => T.by_tac (
boehmes@37126
   693
    NAMED ctxt' "simp (theory)" (Simplifier.simp_tac simpset)
boehmes@36898
   694
    THEN_ALL_NEW (
boehmes@37126
   695
      NAMED ctxt' "fast (theory)" (Classical.fast_tac HOL_cs)
boehmes@37126
   696
      ORELSE' NAMED ctxt' "arith (theory)" (Arith_Data.arith_tac ctxt')))),
boehmes@37126
   697
  T.by_abstraction (true, true) ctxt [] (fn ctxt' => T.by_tac (
boehmes@37126
   698
    NAMED ctxt' "simp (full)" (Simplifier.simp_tac simpset)
boehmes@37126
   699
    THEN_ALL_NEW (
boehmes@37126
   700
      NAMED ctxt' "fast (full)" (Classical.fast_tac HOL_cs)
boehmes@37126
   701
      ORELSE' NAMED ctxt' "arith (full)" (Arith_Data.arith_tac ctxt'))))])
boehmes@36898
   702
boehmes@36898
   703
end
boehmes@36898
   704
boehmes@36898
   705
boehmes@36898
   706
boehmes@36898
   707
(** proof reconstruction **)
boehmes@36898
   708
boehmes@36898
   709
(* tracing and checking *)
boehmes@36898
   710
boehmes@36898
   711
local
boehmes@36898
   712
  fun count_rules ptab =
boehmes@36898
   713
    let
boehmes@36898
   714
      fun count (_, Unproved _) (solved, total) = (solved, total + 1)
boehmes@36898
   715
        | count (_, Proved _) (solved, total) = (solved + 1, total + 1)
boehmes@36898
   716
    in Inttab.fold count ptab (0, 0) end
boehmes@36898
   717
boehmes@36898
   718
  fun header idx r (solved, total) = 
boehmes@36898
   719
    "Z3: #" ^ string_of_int idx ^ ": " ^ P.string_of_rule r ^ " (goal " ^
boehmes@36898
   720
    string_of_int (solved + 1) ^ " of " ^ string_of_int total ^ ")"
boehmes@36898
   721
boehmes@36898
   722
  fun check ctxt idx r ps ct p =
boehmes@36898
   723
    let val thm = thm_of p |> tap (Thm.join_proofs o single)
boehmes@36898
   724
    in
boehmes@36898
   725
      if (Thm.cprop_of thm) aconvc ct then ()
boehmes@36898
   726
      else z3_exn (Pretty.string_of (Pretty.big_list ("proof step failed: " ^
boehmes@36898
   727
        quote (P.string_of_rule r) ^ " (#" ^ string_of_int idx ^ ")")
boehmes@36898
   728
          (pretty_goal ctxt (map (thm_of o fst) ps) (Thm.prop_of thm) @
boehmes@36898
   729
           [Pretty.block [Pretty.str "expected: ",
boehmes@36898
   730
            Syntax.pretty_term ctxt (Thm.term_of ct)]])))
boehmes@36898
   731
    end
boehmes@36898
   732
in
boehmes@36898
   733
fun trace_rule idx prove r ps ct (cxp as (ctxt, ptab)) =
boehmes@36898
   734
  let
boehmes@36898
   735
    val _ = SMT_Solver.trace_msg ctxt (header idx r o count_rules) ptab
boehmes@36899
   736
    val result as (p, (ctxt', _)) = prove r ps ct cxp
boehmes@36898
   737
    val _ = if not (Config.get ctxt' SMT_Solver.trace) then ()
boehmes@36898
   738
      else check ctxt' idx r ps ct p
boehmes@36898
   739
  in result end
boehmes@36898
   740
end
boehmes@36898
   741
boehmes@36898
   742
boehmes@36898
   743
(* overall reconstruction procedure *)
boehmes@36898
   744
boehmes@40164
   745
local
boehmes@40164
   746
  fun not_supported r = raise Fail ("Z3: proof rule not implemented: " ^
boehmes@40164
   747
    quote (P.string_of_rule r))
boehmes@36898
   748
boehmes@40164
   749
  fun step assms simpset vars r ps ct (cxp as (cx, ptab)) =
boehmes@40164
   750
    (case (r, ps) of
boehmes@40164
   751
      (* core rules *)
boehmes@40164
   752
      (P.TrueAxiom, _) => (Thm L.true_thm, cxp)
boehmes@40164
   753
    | (P.Asserted, _) => (asserted cx assms ct, cxp)
boehmes@40164
   754
    | (P.Goal, _) => (asserted cx assms ct, cxp)
boehmes@40164
   755
    | (P.ModusPonens, [(p, _), (q, _)]) => (mp q (thm_of p), cxp)
boehmes@40164
   756
    | (P.ModusPonensOeq, [(p, _), (q, _)]) => (mp q (thm_of p), cxp)
boehmes@40164
   757
    | (P.AndElim, [(p, i)]) => and_elim (p, i) ct ptab ||> pair cx
boehmes@40164
   758
    | (P.NotOrElim, [(p, i)]) => not_or_elim (p, i) ct ptab ||> pair cx
boehmes@40164
   759
    | (P.Hypothesis, _) => (Thm (Thm.assume ct), cxp)
boehmes@40164
   760
    | (P.Lemma, [(p, _)]) => (lemma (thm_of p) ct, cxp)
boehmes@40164
   761
    | (P.UnitResolution, (p, _) :: ps) =>
boehmes@40164
   762
        (unit_resolution (thm_of p) (map (thm_of o fst) ps) ct, cxp)
boehmes@40164
   763
    | (P.IffTrue, [(p, _)]) => (iff_true (thm_of p), cxp)
boehmes@40164
   764
    | (P.IffFalse, [(p, _)]) => (iff_false (thm_of p), cxp)
boehmes@40164
   765
    | (P.Distributivity, _) => (distributivity cx ct, cxp)
boehmes@40164
   766
    | (P.DefAxiom, _) => (def_axiom cx ct, cxp)
boehmes@40164
   767
    | (P.IntroDef, _) => intro_def ct cx ||> rpair ptab
boehmes@40164
   768
    | (P.ApplyDef, [(p, _)]) => (apply_def (thm_of p), cxp)
boehmes@40164
   769
    | (P.IffOeq, [(p, _)]) => (p, cxp)
boehmes@40164
   770
    | (P.NnfPos, _) => (nnf cx vars (map fst ps) ct, cxp)
boehmes@40164
   771
    | (P.NnfNeg, _) => (nnf cx vars (map fst ps) ct, cxp)
boehmes@36898
   772
boehmes@40164
   773
      (* equality rules *)
boehmes@40164
   774
    | (P.Reflexivity, _) => (refl ct, cxp)
boehmes@40164
   775
    | (P.Symmetry, [(p, _)]) => (symm p, cxp)
boehmes@40164
   776
    | (P.Transitivity, [(p, _), (q, _)]) => (trans p q, cxp)
boehmes@40164
   777
    | (P.Monotonicity, _) => (monotonicity (map fst ps) ct, cxp)
boehmes@40164
   778
    | (P.Commutativity, _) => (commutativity ct, cxp)
boehmes@40164
   779
boehmes@40164
   780
      (* quantifier rules *)
boehmes@40164
   781
    | (P.QuantIntro, [(p, _)]) => (quant_intro vars p ct, cxp)
boehmes@40164
   782
    | (P.PullQuant, _) => (pull_quant cx ct, cxp)
boehmes@40164
   783
    | (P.PushQuant, _) => (push_quant cx ct, cxp)
boehmes@40164
   784
    | (P.ElimUnusedVars, _) => (elim_unused_vars cx ct, cxp)
boehmes@40164
   785
    | (P.DestEqRes, _) => (dest_eq_res cx ct, cxp)
boehmes@40164
   786
    | (P.QuantInst, _) => (quant_inst ct, cxp)
boehmes@40164
   787
    | (P.Skolemize, _) => skolemize ct cx ||> rpair ptab
boehmes@40164
   788
boehmes@40164
   789
      (* theory rules *)
boehmes@40164
   790
    | (P.ThLemma, _) =>
boehmes@40164
   791
        (th_lemma cx simpset (map (thm_of o fst) ps) ct, cxp)
boehmes@40164
   792
    | (P.Rewrite, _) => (rewrite cx simpset [] ct, cxp)
boehmes@40164
   793
    | (P.RewriteStar, ps) =>
boehmes@40164
   794
        (rewrite cx simpset (map fst ps) ct, cxp)
boehmes@36898
   795
boehmes@40164
   796
    | (P.NnfStar, _) => not_supported r
boehmes@40164
   797
    | (P.CnfStar, _) => not_supported r
boehmes@40164
   798
    | (P.TransitivityStar, _) => not_supported r
boehmes@40164
   799
    | (P.PullQuantStar, _) => not_supported r
boehmes@36898
   800
boehmes@40164
   801
    | _ => raise Fail ("Z3: proof rule " ^ quote (P.string_of_rule r) ^
boehmes@40164
   802
       " has an unexpected number of arguments."))
boehmes@36898
   803
boehmes@40164
   804
  fun prove ctxt assms vars =
boehmes@40164
   805
    let
boehmes@40164
   806
      val simpset = T.make_simpset ctxt (Z3_Simps.get ctxt)
boehmes@40164
   807
 
boehmes@40164
   808
      fun conclude idx rule prop (ps, cxp) =
boehmes@40164
   809
        trace_rule idx (step assms simpset vars) rule ps prop cxp
boehmes@40164
   810
        |-> (fn p => apsnd (Inttab.update (idx, Proved p)) #> pair p)
boehmes@40164
   811
 
boehmes@40164
   812
      fun lookup idx (cxp as (_, ptab)) =
boehmes@40164
   813
        (case Inttab.lookup ptab idx of
boehmes@40164
   814
          SOME (Unproved (P.Proof_Step {rule, prems, prop})) =>
boehmes@40164
   815
            fold_map lookup prems cxp
boehmes@40164
   816
            |>> map2 rpair prems
boehmes@40164
   817
            |> conclude idx rule prop
boehmes@40164
   818
        | SOME (Proved p) => (p, cxp)
boehmes@40164
   819
        | NONE => z3_exn ("unknown proof id: " ^ quote (string_of_int idx)))
boehmes@40164
   820
 
boehmes@40164
   821
      fun result (p, (cx, _)) = (thm_of p, cx)
boehmes@40164
   822
    in
boehmes@40164
   823
      (fn idx => result o lookup idx o pair ctxt o Inttab.map (K Unproved))
boehmes@40164
   824
    end
boehmes@36898
   825
boehmes@40164
   826
  fun filter_assms ctxt assms ptab =
boehmes@40164
   827
    let
boehmes@40164
   828
      fun step r ct =
boehmes@40164
   829
        (case r of
boehmes@40164
   830
          P.Asserted => insert (op =) (find_assm ctxt assms ct)
boehmes@40164
   831
        | P.Goal => insert (op =) (find_assm ctxt assms ct)
boehmes@40164
   832
        | _ => I)
boehmes@36898
   833
boehmes@40164
   834
      fun lookup idx =
boehmes@40164
   835
        (case Inttab.lookup ptab idx of
boehmes@40164
   836
          SOME (P.Proof_Step {rule, prems, prop}) =>
boehmes@40164
   837
            fold lookup prems #> step rule prop
boehmes@40164
   838
        | NONE => z3_exn ("unknown proof id: " ^ quote (string_of_int idx)))
boehmes@40164
   839
    in lookup end
boehmes@40164
   840
in
boehmes@40164
   841
boehmes@40164
   842
fun reconstruct ctxt {typs, terms, unfolds, assms} output =
boehmes@40164
   843
  let
boehmes@40164
   844
    val (idx, (ptab, vars, cx)) = P.parse ctxt typs terms output
boehmes@40164
   845
    val assms' = prepare_assms cx unfolds assms
boehmes@36898
   846
  in
boehmes@40164
   847
    if Config.get cx SMT_Solver.filter_only
boehmes@40164
   848
    then ((filter_assms cx assms' ptab idx [], @{thm TrueI}), cx)
boehmes@40164
   849
    else apfst (pair []) (prove cx assms' vars idx ptab)
boehmes@36898
   850
  end
boehmes@36898
   851
boehmes@40164
   852
end
boehmes@36898
   853
boehmes@40164
   854
val setup = z3_rules_setup #> Z3_Simps.setup
boehmes@36898
   855
boehmes@36898
   856
end