fine-tuned Isar reconstruction, esp. boolean simplifications

--- a/src/HOL/Tools/ATP/atp_proof_reconstruct.ML	Fri Aug 01 23:29:49 2014 +0200
+++ b/src/HOL/Tools/ATP/atp_proof_reconstruct.ML	Fri Aug 01 23:29:50 2014 +0200
@@ -107,13 +107,20 @@
     let val t' = simplify_bool t in
       if loose_bvar1 (t', 0) then all $ Abs (s, T, t') else t'
     end
-  | simplify_bool (@{const Not} $ t) = s_not (simplify_bool t)
-  | simplify_bool (@{const conj} $ t $ u) = s_conj (simplify_bool t, simplify_bool u)
-  | simplify_bool (@{const disj} $ t $ u) = s_disj (simplify_bool t, simplify_bool u)
-  | simplify_bool (@{const implies} $ t $ u) = s_imp (simplify_bool t, simplify_bool u)
-  | simplify_bool (@{const HOL.eq (bool)} $ t $ u) = s_iff (simplify_bool t, simplify_bool u)
-  | simplify_bool (t as Const (@{const_name HOL.eq}, _) $ u $ v) =
-    if u aconv v then @{const True} else t
+  | simplify_bool (Const (@{const_name Not}, _) $ t) = s_not (simplify_bool t)
+  | simplify_bool (Const (@{const_name conj}, _) $ t $ u) =
+    s_conj (simplify_bool t, simplify_bool u)
+  | simplify_bool (Const (@{const_name disj}, _) $ t $ u) =
+    s_disj (simplify_bool t, simplify_bool u)
+  | simplify_bool (Const (@{const_name implies}, _) $ t $ u) =
+    s_imp (simplify_bool t, simplify_bool u)
+  | simplify_bool ((t as Const (@{const_name HOL.eq}, _)) $ u $ v) =
+    (case (u, v) of
+      (Const (@{const_name True}, _), _) => v
+    | (u, Const (@{const_name True}, _)) => u
+    | (Const (@{const_name False}, _), v) => s_not v
+    | (u, Const (@{const_name False}, _)) => s_not u
+    | _ => if u aconv v then @{const True} else t $ simplify_bool u $ simplify_bool v)
   | simplify_bool (t $ u) = simplify_bool t $ simplify_bool u
   | simplify_bool (Abs (s, T, t)) = Abs (s, T, simplify_bool t)
   | simplify_bool t = t
@@ -246,47 +253,27 @@
 
 
 (* Higher-order translation. Variables are typed (although we don't use that information). Lambdas
-   are typed.
-
-  The code is similar to term_of_atp_fo. *)
-fun term_of_atp_ho ctxt textual sym_tab =
+   are typed. The code is similar to "term_of_atp_fo". *)
+fun term_of_atp_ho ctxt sym_tab =
   let
     val thy = Proof_Context.theory_of ctxt
-    val var_index = var_index_of_textual textual
+    val var_index = var_index_of_textual true
 
     fun do_term opt_T u =
       (case u of
         AAbs(((var, ty), term), []) =>
         let
           val typ = typ_of_atp_type ctxt ty
-          val var_name = repair_var_name textual var
+          val var_name = repair_var_name true var
           val tm = do_term NONE term
-        in quantify_over_var textual lambda' var_name typ tm end
+        in quantify_over_var true lambda' var_name typ tm end
       | ATerm ((s, tys), us) =>
         if s = ""
         then error "Isar proof reconstruction failed because the ATP proof \
                      \contains unparsable material."
         else if s = tptp_equal then
-          let
-            val ts = map (do_term NONE) us
-            fun equal_term ts =
-                list_comb (Const (@{const_name HOL.eq}, Type_Infer.anyT @{sort type}), ts)
-          in
-            if textual then
-              (case ts of
-                [t1, t2] =>
-                if loose_aconv (t1, t2) then
-                  @{const True}
-                else if Term.aconv_untyped (t2, @{const True}) then
-                  t1
-                else if Term.aconv_untyped (t1, @{const True}) then
-                  t2
-                else
-                  equal_term ts
-              | _ => equal_term ts)
-            else
-              equal_term ts
-          end
+          list_comb (Const (@{const_name HOL.eq}, Type_Infer.anyT @{sort type}),
+            map (do_term NONE) us)
         else if not (null us) then
           let
             val args = List.map (do_term NONE) us
@@ -297,10 +284,10 @@
         else if s = tptp_and then HOLogic.conj
         else if s = tptp_implies then HOLogic.imp
         else if s = tptp_iff orelse s = tptp_equal then HOLogic.eq_const dummyT
-        else if s = tptp_not_iff orelse s = tptp_not_equal then @{term "% P Q. Q ~= P"}
-        else if s = tptp_if then @{term "% P Q. Q --> P"}
-        else if s = tptp_not_and then @{term "% P Q. ~ (P & Q)"}
-        else if s = tptp_not_or then @{term "% P Q. ~ (P | Q)"}
+        else if s = tptp_not_iff orelse s = tptp_not_equal then @{term "%P Q. Q ~= P"}
+        else if s = tptp_if then @{term "%P Q. Q --> P"}
+        else if s = tptp_not_and then @{term "%P Q. ~ (P & Q)"}
+        else if s = tptp_not_or then @{term "%P Q. ~ (P | Q)"}
         else if s = tptp_not then HOLogic.Not
         else if s = tptp_ho_forall then HOLogic.all_const dummyT
         else if s = tptp_ho_exists then HOLogic.exists_const dummyT
@@ -317,7 +304,7 @@
               val Ts = map (typ_of_atp_type ctxt) tys @ map (typ_of_atp_term ctxt) type_us
               val T =
                 (if not (null Ts) andalso robust_const_num_type_args thy s' = length Ts then
-                   if textual then try (Sign.const_instance thy) (s', Ts) else NONE
+                   try (Sign.const_instance thy) (s', Ts)
                  else
                    NONE)
                 |> (fn SOME T => T
@@ -343,10 +330,8 @@
                 (case unprefix_and_unascii fixed_var_prefix s of
                   SOME s => Free (s, T)
                 | NONE =>
-                  if textual andalso not (is_tptp_variable s) then
-                    Free (s |> textual ? (repair_var_name_raw #> fresh_up), T)
-                  else
-                    Var ((repair_var_name textual s, var_index), T))
+                  if not (is_tptp_variable s) then Free (s |> repair_var_name_raw |> fresh_up, T)
+                  else Var ((repair_var_name true s, var_index), T))
             in list_comb (t, ts) end))
   in do_term end
 
@@ -369,12 +354,8 @@
         else if String.isPrefix native_type_prefix s then
           @{const True} (* ignore TPTP type information *)
         else if s = tptp_equal then
-          let val ts = map (do_term [] NONE) us in
-            if textual andalso length ts = 2 andalso loose_aconv (hd ts, List.last ts) then
-              @{const True}
-            else
-              list_comb (Const (@{const_name HOL.eq}, Type_Infer.anyT @{sort type}), ts)
-          end
+          list_comb (Const (@{const_name HOL.eq}, Type_Infer.anyT @{sort type}),
+            map (do_term [] NONE) us)
         else
           (case unprefix_and_unascii const_prefix s of
             SOME s' =>
@@ -452,12 +433,10 @@
   in do_term [] end
 
 fun term_of_atp ctxt (ATP_Problem.THF _) type_enc =
-    if ATP_Problem_Generate.is_type_enc_higher_order type_enc
-    then term_of_atp_ho ctxt
+    if ATP_Problem_Generate.is_type_enc_higher_order type_enc then K (term_of_atp_ho ctxt)
     else error "Unsupported Isar reconstruction."
   | term_of_atp ctxt _ type_enc =
-    if not (ATP_Problem_Generate.is_type_enc_higher_order type_enc)
-    then term_of_atp_fo ctxt
+    if not (ATP_Problem_Generate.is_type_enc_higher_order type_enc) then term_of_atp_fo ctxt
     else error "Unsupported Isar reconstruction."
 
 fun term_of_atom ctxt format type_enc textual sym_tab pos (u as ATerm ((s, _), _)) =
@@ -633,6 +612,7 @@
         |> prop_of_atp ctxt format type_enc true sym_tab
         |> unlift_term lifted
         |> uncombine_term thy
+        |> simplify_bool
     in
       SOME (name, role, t, rule, deps)
     end

--- a/src/HOL/Tools/SMT2/smtlib2_isar.ML	Fri Aug 01 23:29:49 2014 +0200
+++ b/src/HOL/Tools/SMT2/smtlib2_isar.ML	Fri Aug 01 23:29:50 2014 +0200
@@ -11,15 +11,16 @@
   val postprocess_step_conclusion: theory -> thm list -> term list -> term -> term
   val normalizing_prems : Proof.context -> term -> (string * string list) list
   val distinguish_conjecture_and_hypothesis : ''a list -> ''b -> ''b -> ''b list ->
-    (''a * 'c) list -> 'c list -> 'c -> 'c -> (ATP_Problem.atp_formula_role * 'c) option
+    (''a * 'c) list -> 'c list -> 'c -> (ATP_Problem.atp_formula_role * 'c) option
   val unskolemize_names: term -> term
 end;
 
 structure SMTLIB2_Isar: SMTLIB2_ISAR =
 struct
 
+open ATP_Util
 open ATP_Problem
-open ATP_Util
+open ATP_Proof_Reconstruct
 
 fun unlift_term ll_defs =
   let
@@ -42,6 +43,7 @@
   Raw_Simplifier.rewrite_term thy rewrite_rules []
   #> Object_Logic.atomize_term thy
   #> not (null ll_defs) ? unlift_term ll_defs
+  #> simplify_bool
   #> unskolemize_names
   #> HOLogic.mk_Trueprop
 
@@ -54,8 +56,8 @@
     else
       NONE)
 
-fun distinguish_conjecture_and_hypothesis ss id conjecture_id prem_ids fact_helper_ts hyp_ts concl_t
-    t =
+fun distinguish_conjecture_and_hypothesis ss id conjecture_id prem_ids fact_helper_ts hyp_ts
+    concl_t =
   (case ss of
     [s] => SOME (Axiom, the (AList.lookup (op =) fact_helper_ts s))
   | _ =>

--- a/src/HOL/Tools/SMT2/verit_isar.ML	Fri Aug 01 23:29:49 2014 +0200
+++ b/src/HOL/Tools/SMT2/verit_isar.ML	Fri Aug 01 23:29:50 2014 +0200
@@ -35,7 +35,7 @@
         if rule = veriT_input_rule then
           let val ss = the_list (AList.lookup (op =) fact_helper_ids (the (Int.fromString id))) in
             (case distinguish_conjecture_and_hypothesis ss (the (Int.fromString id))
-                conjecture_id prem_ids fact_helper_ts hyp_ts concl_t concl of
+                conjecture_id prem_ids fact_helper_ts hyp_ts concl_t of
               NONE => []
             | SOME (role0, concl00) =>
               let

--- a/src/HOL/Tools/SMT2/z3_new_isar.ML	Fri Aug 01 23:29:49 2014 +0200
+++ b/src/HOL/Tools/SMT2/z3_new_isar.ML	Fri Aug 01 23:29:50 2014 +0200
@@ -94,7 +94,7 @@
           Z3_New_Proof.Asserted =>
           let val ss = the_list (AList.lookup (op =) fact_helper_ids id) in
             (case distinguish_conjecture_and_hypothesis ss id conjecture_id prem_ids fact_helper_ts
-                hyp_ts concl_t concl of
+                hyp_ts concl_t of
               NONE => []
             | SOME (role0, concl00) =>
               let

--- a/src/HOL/Tools/Sledgehammer/sledgehammer_isar.ML	Fri Aug 01 23:29:49 2014 +0200
+++ b/src/HOL/Tools/Sledgehammer/sledgehammer_isar.ML	Fri Aug 01 23:29:50 2014 +0200
@@ -89,7 +89,8 @@
       line :: lines
     else if role = Axiom then
       lines (* axioms (facts) need no proof lines *)
-    else map (replace_dependencies_in_line (name, [])) lines
+    else
+      map (replace_dependencies_in_line (name, [])) lines
   | add_line_pass1 line lines = line :: lines
 
 fun add_lines_pass2 res _ [] = rev res
@@ -210,7 +211,7 @@
 
         val rule_of_clause_id = fst o the o Symtab.lookup steps o fst
 
-        val finish_off = simplify_bool #> close_form #> rename_bound_vars
+        val finish_off = close_form #> rename_bound_vars
 
         fun prop_of_clause [(num, _)] = Symtab.lookup steps num |> the |> snd |> finish_off
           | prop_of_clause names =

--- a/src/HOL/Tools/Sledgehammer/sledgehammer_isar_compress.ML	Fri Aug 01 23:29:49 2014 +0200
+++ b/src/HOL/Tools/Sledgehammer/sledgehammer_isar_compress.ML	Fri Aug 01 23:29:50 2014 +0200
@@ -98,7 +98,7 @@
        subproofs1 @ subproofs2, (lfs, gfs), meths, comment1 ^ comment2), hopeless)
   end
 
-val merge_slack_time = seconds 0.005
+val merge_slack_time = seconds 0.01
 val merge_slack_factor = 1.5
 
 fun adjust_merge_timeout max time =
@@ -117,7 +117,7 @@
       val (compress_further, decrement_step_count) =
         let
           val number_of_steps = add_isar_steps (steps_of_isar_proof proof) 0
-          val target_number_of_steps = Real.round (Real.fromInt number_of_steps / compress)
+          val target_number_of_steps = Real.ceil (Real.fromInt number_of_steps / compress)
           val delta = Unsynchronized.ref (number_of_steps - target_number_of_steps)
         in
           (fn () => !delta > 0, fn () => delta := !delta - 1)
@@ -273,8 +273,9 @@
         if compress_further () then Proof (xs, assms, compress_steps steps) else proof
       and compress_steps steps =
         (* bottom-up: compress innermost proofs first *)
-        steps |> map (fn step => step |> compress_further () ? compress_sub_levels)
-              |> compress_further () ? compress_top_level
+        steps
+        |> map (fn step => step |> compress_further () ? compress_sub_levels)
+        |> compress_further () ? compress_top_level
       and compress_sub_levels (Prove (qs, xs, l, t, subproofs, facts, meths, comment)) =
           (* compress subproofs *)
           Prove (qs, xs, l, t, map compress_proof subproofs, facts, meths, comment)