--- a/src/HOL/IMP/Abs_Int2.thy Thu Apr 19 11:55:30 2012 +0200
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,683 +0,0 @@
-(* Author: Tobias Nipkow *)
-
-theory Abs_Int2
-imports Abs_Int1_ivl
-begin
-
-subsection "Widening and Narrowing"
-
-class WN = SL_top +
-fixes widen :: "'a \<Rightarrow> 'a \<Rightarrow> 'a" (infix "\<nabla>" 65)
-assumes widen1: "x \<sqsubseteq> x \<nabla> y"
-assumes widen2: "y \<sqsubseteq> x \<nabla> y"
-fixes narrow :: "'a \<Rightarrow> 'a \<Rightarrow> 'a" (infix "\<triangle>" 65)
-assumes narrow1: "y \<sqsubseteq> x \<Longrightarrow> y \<sqsubseteq> x \<triangle> y"
-assumes narrow2: "y \<sqsubseteq> x \<Longrightarrow> x \<triangle> y \<sqsubseteq> x"
-
-
-subsubsection "Intervals"
-
-instantiation ivl :: WN
-begin
-
-definition "widen_ivl ivl1 ivl2 =
- ((*if is_empty ivl1 then ivl2 else
- if is_empty ivl2 then ivl1 else*)
- case (ivl1,ivl2) of (I l1 h1, I l2 h2) \<Rightarrow>
- I (if le_option False l2 l1 \<and> l2 \<noteq> l1 then None else l1)
- (if le_option True h1 h2 \<and> h1 \<noteq> h2 then None else h1))"
-
-definition "narrow_ivl ivl1 ivl2 =
- ((*if is_empty ivl1 \<or> is_empty ivl2 then empty else*)
- case (ivl1,ivl2) of (I l1 h1, I l2 h2) \<Rightarrow>
- I (if l1 = None then l2 else l1)
- (if h1 = None then h2 else h1))"
-
-instance
-proof qed
- (auto simp add: widen_ivl_def narrow_ivl_def le_option_def le_ivl_def empty_def split: ivl.split option.split if_splits)
-
-end
-
-
-subsubsection "Abstract State"
-
-instantiation st :: (WN)WN
-begin
-
-definition "widen_st F1 F2 =
- FunDom (\<lambda>x. fun F1 x \<nabla> fun F2 x) (inter_list (dom F1) (dom F2))"
-
-definition "narrow_st F1 F2 =
- FunDom (\<lambda>x. fun F1 x \<triangle> fun F2 x) (inter_list (dom F1) (dom F2))"
-
-instance
-proof
- case goal1 thus ?case
- by(simp add: widen_st_def le_st_def lookup_def widen1)
-next
- case goal2 thus ?case
- by(simp add: widen_st_def le_st_def lookup_def widen2)
-next
- case goal3 thus ?case
- by(auto simp: narrow_st_def le_st_def lookup_def narrow1)
-next
- case goal4 thus ?case
- by(auto simp: narrow_st_def le_st_def lookup_def narrow2)
-qed
-
-end
-
-
-subsubsection "Option"
-
-instantiation option :: (WN)WN
-begin
-
-fun widen_option where
-"None \<nabla> x = x" |
-"x \<nabla> None = x" |
-"(Some x) \<nabla> (Some y) = Some(x \<nabla> y)"
-
-fun narrow_option where
-"None \<triangle> x = None" |
-"x \<triangle> None = None" |
-"(Some x) \<triangle> (Some y) = Some(x \<triangle> y)"
-
-instance
-proof
- case goal1 show ?case
- by(induct x y rule: widen_option.induct) (simp_all add: widen1)
-next
- case goal2 show ?case
- by(induct x y rule: widen_option.induct) (simp_all add: widen2)
-next
- case goal3 thus ?case
- by(induct x y rule: narrow_option.induct) (simp_all add: narrow1)
-next
- case goal4 thus ?case
- by(induct x y rule: narrow_option.induct) (simp_all add: narrow2)
-qed
-
-end
-
-
-subsubsection "Annotated commands"
-
-fun map2_acom :: "('a \<Rightarrow> 'a \<Rightarrow> 'a) \<Rightarrow> 'a acom \<Rightarrow> 'a acom \<Rightarrow> 'a acom" where
-"map2_acom f (SKIP {a1}) (SKIP {a2}) = (SKIP {f a1 a2})" |
-"map2_acom f (x ::= e {a1}) (x' ::= e' {a2}) = (x ::= e {f a1 a2})" |
-"map2_acom f (c1;c2) (c1';c2') = (map2_acom f c1 c1'; map2_acom f c2 c2')" |
-"map2_acom f (IF b THEN c1 ELSE c2 {a1}) (IF b' THEN c1' ELSE c2' {a2}) =
- (IF b THEN map2_acom f c1 c1' ELSE map2_acom f c2 c2' {f a1 a2})" |
-"map2_acom f ({a1} WHILE b DO c {a2}) ({a3} WHILE b' DO c' {a4}) =
- ({f a1 a3} WHILE b DO map2_acom f c c' {f a2 a4})"
-
-abbreviation widen_acom :: "('a::WN)acom \<Rightarrow> 'a acom \<Rightarrow> 'a acom" (infix "\<nabla>\<^sub>c" 65)
-where "widen_acom == map2_acom (op \<nabla>)"
-
-abbreviation narrow_acom :: "('a::WN)acom \<Rightarrow> 'a acom \<Rightarrow> 'a acom" (infix "\<triangle>\<^sub>c" 65)
-where "narrow_acom == map2_acom (op \<triangle>)"
-
-lemma widen1_acom: "strip c = strip c' \<Longrightarrow> c \<sqsubseteq> c \<nabla>\<^sub>c c'"
-by(induct c c' rule: le_acom.induct)(simp_all add: widen1)
-
-lemma widen2_acom: "strip c = strip c' \<Longrightarrow> c' \<sqsubseteq> c \<nabla>\<^sub>c c'"
-by(induct c c' rule: le_acom.induct)(simp_all add: widen2)
-
-lemma narrow1_acom: "y \<sqsubseteq> x \<Longrightarrow> y \<sqsubseteq> x \<triangle>\<^sub>c y"
-by(induct y x rule: le_acom.induct) (simp_all add: narrow1)
-
-lemma narrow2_acom: "y \<sqsubseteq> x \<Longrightarrow> x \<triangle>\<^sub>c y \<sqsubseteq> x"
-by(induct y x rule: le_acom.induct) (simp_all add: narrow2)
-
-
-subsubsection "Post-fixed point computation"
-
-definition iter_widen :: "('a acom \<Rightarrow> 'a acom) \<Rightarrow> 'a acom \<Rightarrow> ('a::WN)acom option"
-where "iter_widen f = while_option (\<lambda>c. \<not> f c \<sqsubseteq> c) (\<lambda>c. c \<nabla>\<^sub>c f c)"
-
-definition iter_narrow :: "('a acom \<Rightarrow> 'a acom) \<Rightarrow> 'a acom \<Rightarrow> 'a::WN acom option"
-where "iter_narrow f = while_option (\<lambda>c. \<not> c \<sqsubseteq> c \<triangle>\<^sub>c f c) (\<lambda>c. c \<triangle>\<^sub>c f c)"
-
-definition pfp_wn ::
- "(('a::WN)option acom \<Rightarrow> 'a option acom) \<Rightarrow> com \<Rightarrow> 'a option acom option"
-where "pfp_wn f c = (case iter_widen f (\<bottom>\<^sub>c c) of None \<Rightarrow> None
- | Some c' \<Rightarrow> iter_narrow f c')"
-
-lemma strip_map2_acom:
- "strip c1 = strip c2 \<Longrightarrow> strip(map2_acom f c1 c2) = strip c1"
-by(induct f c1 c2 rule: map2_acom.induct) simp_all
-
-lemma iter_widen_pfp: "iter_widen f c = Some c' \<Longrightarrow> f c' \<sqsubseteq> c'"
-by(auto simp add: iter_widen_def dest: while_option_stop)
-
-lemma strip_while: fixes f :: "'a acom \<Rightarrow> 'a acom"
-assumes "\<forall>c. strip (f c) = strip c" and "while_option P f c = Some c'"
-shows "strip c' = strip c"
-using while_option_rule[where P = "\<lambda>c'. strip c' = strip c", OF _ assms(2)]
-by (metis assms(1))
-
-lemma strip_iter_widen: fixes f :: "'a::WN acom \<Rightarrow> 'a acom"
-assumes "\<forall>c. strip (f c) = strip c" and "iter_widen f c = Some c'"
-shows "strip c' = strip c"
-proof-
- have "\<forall>c. strip(c \<nabla>\<^sub>c f c) = strip c" by (metis assms(1) strip_map2_acom)
- from strip_while[OF this] assms(2) show ?thesis by(simp add: iter_widen_def)
-qed
-
-lemma iter_narrow_pfp: assumes "mono f" and "f c0 \<sqsubseteq> c0"
-and "iter_narrow f c0 = Some c"
-shows "f c \<sqsubseteq> c \<and> c \<sqsubseteq> c0" (is "?P c")
-proof-
- { fix c assume "?P c"
- note 1 = conjunct1[OF this] and 2 = conjunct2[OF this]
- let ?c' = "c \<triangle>\<^sub>c f c"
- have "?P ?c'"
- proof
- have "f ?c' \<sqsubseteq> f c" by(rule monoD[OF `mono f` narrow2_acom[OF 1]])
- also have "\<dots> \<sqsubseteq> ?c'" by(rule narrow1_acom[OF 1])
- finally show "f ?c' \<sqsubseteq> ?c'" .
- have "?c' \<sqsubseteq> c" by (rule narrow2_acom[OF 1])
- also have "c \<sqsubseteq> c0" by(rule 2)
- finally show "?c' \<sqsubseteq> c0" .
- qed
- }
- with while_option_rule[where P = ?P, OF _ assms(3)[simplified iter_narrow_def]]
- assms(2) le_refl
- show ?thesis by blast
-qed
-
-lemma pfp_wn_pfp:
- "\<lbrakk> mono f; pfp_wn f c = Some c' \<rbrakk> \<Longrightarrow> f c' \<sqsubseteq> c'"
-unfolding pfp_wn_def
-by (auto dest: iter_widen_pfp iter_narrow_pfp split: option.splits)
-
-lemma strip_pfp_wn:
- "\<lbrakk> \<forall>c. strip(f c) = strip c; pfp_wn f c = Some c' \<rbrakk> \<Longrightarrow> strip c' = c"
-apply(auto simp add: pfp_wn_def iter_narrow_def split: option.splits)
-by (metis (no_types) strip_map2_acom strip_while strip_bot_acom strip_iter_widen)
-
-locale Abs_Int2 = Abs_Int1_mono
-where \<gamma>=\<gamma> for \<gamma> :: "'av::{WN,L_top_bot} \<Rightarrow> val set"
-begin
-
-definition AI_wn :: "com \<Rightarrow> 'av st option acom option" where
-"AI_wn = pfp_wn (step' \<top>)"
-
-lemma AI_wn_sound: "AI_wn c = Some c' \<Longrightarrow> CS c \<le> \<gamma>\<^isub>c c'"
-proof(simp add: CS_def AI_wn_def)
- assume 1: "pfp_wn (step' \<top>) c = Some c'"
- from pfp_wn_pfp[OF mono_step'2 1]
- have 2: "step' \<top> c' \<sqsubseteq> c'" .
- have 3: "strip (\<gamma>\<^isub>c (step' \<top> c')) = c" by(simp add: strip_pfp_wn[OF _ 1])
- have "lfp (step UNIV) c \<le> \<gamma>\<^isub>c (step' \<top> c')"
- proof(rule lfp_lowerbound[simplified,OF 3])
- show "step UNIV (\<gamma>\<^isub>c (step' \<top> c')) \<le> \<gamma>\<^isub>c (step' \<top> c')"
- proof(rule step_preserves_le[OF _ _])
- show "UNIV \<subseteq> \<gamma>\<^isub>o \<top>" by simp
- show "\<gamma>\<^isub>c (step' \<top> c') \<le> \<gamma>\<^isub>c c'" by(rule mono_gamma_c[OF 2])
- qed
- qed
- from this 2 show "lfp (step UNIV) c \<le> \<gamma>\<^isub>c c'"
- by (blast intro: mono_gamma_c order_trans)
-qed
-
-end
-
-interpretation Abs_Int2
-where \<gamma> = \<gamma>_ivl and num' = num_ivl and plus' = plus_ivl
-and test_num' = in_ivl
-and filter_plus' = filter_plus_ivl and filter_less' = filter_less_ivl
-defines AI_ivl' is AI_wn
-..
-
-
-subsubsection "Tests"
-
-definition "step_up_ivl n = ((\<lambda>c. c \<nabla>\<^sub>c step_ivl \<top> c)^^n)"
-definition "step_down_ivl n = ((\<lambda>c. c \<triangle>\<^sub>c step_ivl \<top> c)^^n)"
-
-text{* For @{const test3_ivl}, @{const AI_ivl} needed as many iterations as
-the loop took to execute. In contrast, @{const AI_ivl'} converges in a
-constant number of steps: *}
-
-value "show_acom (step_up_ivl 1 (\<bottom>\<^sub>c test3_ivl))"
-value "show_acom (step_up_ivl 2 (\<bottom>\<^sub>c test3_ivl))"
-value "show_acom (step_up_ivl 3 (\<bottom>\<^sub>c test3_ivl))"
-value "show_acom (step_up_ivl 4 (\<bottom>\<^sub>c test3_ivl))"
-value "show_acom (step_up_ivl 5 (\<bottom>\<^sub>c test3_ivl))"
-value "show_acom (step_down_ivl 1 (step_up_ivl 5 (\<bottom>\<^sub>c test3_ivl)))"
-value "show_acom (step_down_ivl 2 (step_up_ivl 5 (\<bottom>\<^sub>c test3_ivl)))"
-value "show_acom (step_down_ivl 3 (step_up_ivl 5 (\<bottom>\<^sub>c test3_ivl)))"
-
-text{* Now all the analyses terminate: *}
-
-value "show_acom_opt (AI_ivl' test4_ivl)"
-value "show_acom_opt (AI_ivl' test5_ivl)"
-value "show_acom_opt (AI_ivl' test6_ivl)"
-
-
-subsubsection "Termination: Intervals"
-
-definition m_ivl :: "ivl \<Rightarrow> nat" where
-"m_ivl ivl = (case ivl of I l h \<Rightarrow>
- (case l of None \<Rightarrow> 0 | Some _ \<Rightarrow> 1) + (case h of None \<Rightarrow> 0 | Some _ \<Rightarrow> 1))"
-
-lemma m_ivl_height: "m_ivl ivl \<le> 2"
-by(simp add: m_ivl_def split: ivl.split option.split)
-
-lemma m_ivl_anti_mono: "(y::ivl) \<sqsubseteq> x \<Longrightarrow> m_ivl x \<le> m_ivl y"
-by(auto simp: m_ivl_def le_option_def le_ivl_def
- split: ivl.split option.split if_splits)
-
-lemma m_ivl_widen:
- "~ y \<sqsubseteq> x \<Longrightarrow> m_ivl(x \<nabla> y) < m_ivl x"
-by(auto simp: m_ivl_def widen_ivl_def le_option_def le_ivl_def
- split: ivl.splits option.splits if_splits)
-
-lemma Top_less_ivl: "\<top> \<sqsubseteq> x \<Longrightarrow> m_ivl x = 0"
-by(auto simp: m_ivl_def le_option_def le_ivl_def empty_def Top_ivl_def
- split: ivl.split option.split if_splits)
-
-
-definition n_ivl :: "ivl \<Rightarrow> nat" where
-"n_ivl ivl = 2 - m_ivl ivl"
-
-lemma n_ivl_mono: "(x::ivl) \<sqsubseteq> y \<Longrightarrow> n_ivl x \<le> n_ivl y"
-unfolding n_ivl_def by (metis diff_le_mono2 m_ivl_anti_mono)
-
-lemma n_ivl_narrow:
- "~ x \<sqsubseteq> x \<triangle> y \<Longrightarrow> n_ivl(x \<triangle> y) < n_ivl x"
-by(auto simp: n_ivl_def m_ivl_def narrow_ivl_def le_option_def le_ivl_def
- split: ivl.splits option.splits if_splits)
-
-
-subsubsection "Termination: Abstract State"
-
-definition "m_st m st = (\<Sum>x\<in>set(dom st). m(fun st x))"
-
-lemma m_st_height: assumes "finite X" and "set (dom S) \<subseteq> X"
-shows "m_st m_ivl S \<le> 2 * card X"
-proof(auto simp: m_st_def)
- have "(\<Sum>x\<in>set(dom S). m_ivl (fun S x)) \<le> (\<Sum>x\<in>set(dom S). 2)" (is "?L \<le> _")
- by(rule setsum_mono)(simp add:m_ivl_height)
- also have "\<dots> \<le> (\<Sum>x\<in>X. 2)"
- by(rule setsum_mono3[OF assms]) simp
- also have "\<dots> = 2 * card X" by(simp add: setsum_constant)
- finally show "?L \<le> \<dots>" .
-qed
-
-lemma m_st_anti_mono:
- "S1 \<sqsubseteq> S2 \<Longrightarrow> m_st m_ivl S2 \<le> m_st m_ivl S1"
-proof(auto simp: m_st_def le_st_def lookup_def split: if_splits)
- let ?X = "set(dom S1)" let ?Y = "set(dom S2)"
- let ?f = "fun S1" let ?g = "fun S2"
- assume asm: "\<forall>x\<in>?Y. (x \<in> ?X \<longrightarrow> ?f x \<sqsubseteq> ?g x) \<and> (x \<in> ?X \<or> \<top> \<sqsubseteq> ?g x)"
- hence 1: "\<forall>y\<in>?Y\<inter>?X. m_ivl(?g y) \<le> m_ivl(?f y)" by(simp add: m_ivl_anti_mono)
- have 0: "\<forall>x\<in>?Y-?X. m_ivl(?g x) = 0" using asm by (auto simp: Top_less_ivl)
- have "(\<Sum>y\<in>?Y. m_ivl(?g y)) = (\<Sum>y\<in>(?Y-?X) \<union> (?Y\<inter>?X). m_ivl(?g y))"
- by (metis Un_Diff_Int)
- also have "\<dots> = (\<Sum>y\<in>?Y-?X. m_ivl(?g y)) + (\<Sum>y\<in>?Y\<inter>?X. m_ivl(?g y))"
- by(subst setsum_Un_disjoint) auto
- also have "(\<Sum>y\<in>?Y-?X. m_ivl(?g y)) = 0" using 0 by simp
- also have "0 + (\<Sum>y\<in>?Y\<inter>?X. m_ivl(?g y)) = (\<Sum>y\<in>?Y\<inter>?X. m_ivl(?g y))" by simp
- also have "\<dots> \<le> (\<Sum>y\<in>?Y\<inter>?X. m_ivl(?f y))"
- by(rule setsum_mono)(simp add: 1)
- also have "\<dots> \<le> (\<Sum>y\<in>?X. m_ivl(?f y))"
- by(simp add: setsum_mono3[of "?X" "?Y Int ?X", OF _ Int_lower2])
- finally show "(\<Sum>y\<in>?Y. m_ivl(?g y)) \<le> (\<Sum>x\<in>?X. m_ivl(?f x))"
- by (metis add_less_cancel_left)
-qed
-
-lemma m_st_widen:
-assumes "\<not> S2 \<sqsubseteq> S1" shows "m_st m_ivl (S1 \<nabla> S2) < m_st m_ivl S1"
-proof-
- { let ?X = "set(dom S1)" let ?Y = "set(dom S2)"
- let ?f = "fun S1" let ?g = "fun S2"
- fix x assume "x \<in> ?X" "\<not> lookup S2 x \<sqsubseteq> ?f x"
- have "(\<Sum>x\<in>?X\<inter>?Y. m_ivl(?f x \<nabla> ?g x)) < (\<Sum>x\<in>?X. m_ivl(?f x))" (is "?L < ?R")
- proof cases
- assume "x : ?Y"
- have "?L < (\<Sum>x\<in>?X\<inter>?Y. m_ivl(?f x))"
- proof(rule setsum_strict_mono1, simp)
- show "\<forall>x\<in>?X\<inter>?Y. m_ivl(?f x \<nabla> ?g x) \<le> m_ivl (?f x)"
- by (metis m_ivl_anti_mono widen1)
- next
- show "\<exists>x\<in>?X\<inter>?Y. m_ivl(?f x \<nabla> ?g x) < m_ivl(?f x)"
- using `x:?X` `x:?Y` `\<not> lookup S2 x \<sqsubseteq> ?f x`
- by (metis IntI m_ivl_widen lookup_def)
- qed
- also have "\<dots> \<le> ?R" by(simp add: setsum_mono3[OF _ Int_lower1])
- finally show ?thesis .
- next
- assume "x ~: ?Y"
- have "?L \<le> (\<Sum>x\<in>?X\<inter>?Y. m_ivl(?f x))"
- proof(rule setsum_mono, simp)
- fix x assume "x:?X \<and> x:?Y" show "m_ivl(?f x \<nabla> ?g x) \<le> m_ivl (?f x)"
- by (metis m_ivl_anti_mono widen1)
- qed
- also have "\<dots> < m_ivl(?f x) + \<dots>"
- using m_ivl_widen[OF `\<not> lookup S2 x \<sqsubseteq> ?f x`]
- by (metis Nat.le_refl add_strict_increasing gr0I not_less0)
- also have "\<dots> = (\<Sum>y\<in>insert x (?X\<inter>?Y). m_ivl(?f y))"
- using `x ~: ?Y` by simp
- also have "\<dots> \<le> (\<Sum>x\<in>?X. m_ivl(?f x))"
- by(rule setsum_mono3)(insert `x:?X`, auto)
- finally show ?thesis .
- qed
- } with assms show ?thesis
- by(auto simp: le_st_def widen_st_def m_st_def Int_def)
-qed
-
-definition "n_st m X st = (\<Sum>x\<in>X. m(lookup st x))"
-
-lemma n_st_mono: assumes "set(dom S1) \<subseteq> X" "set(dom S2) \<subseteq> X" "S1 \<sqsubseteq> S2"
-shows "n_st n_ivl X S1 \<le> n_st n_ivl X S2"
-proof-
- have "(\<Sum>x\<in>X. n_ivl(lookup S1 x)) \<le> (\<Sum>x\<in>X. n_ivl(lookup S2 x))"
- apply(rule setsum_mono) using assms
- by(auto simp: le_st_def lookup_def n_ivl_mono split: if_splits)
- thus ?thesis by(simp add: n_st_def)
-qed
-
-lemma n_st_narrow:
-assumes "finite X" and "set(dom S1) \<subseteq> X" "set(dom S2) \<subseteq> X"
-and "S2 \<sqsubseteq> S1" "\<not> S1 \<sqsubseteq> S1 \<triangle> S2"
-shows "n_st n_ivl X (S1 \<triangle> S2) < n_st n_ivl X S1"
-proof-
- have 1: "\<forall>x\<in>X. n_ivl (lookup (S1 \<triangle> S2) x) \<le> n_ivl (lookup S1 x)"
- using assms(2-4)
- by(auto simp: le_st_def narrow_st_def lookup_def n_ivl_mono narrow2
- split: if_splits)
- have 2: "\<exists>x\<in>X. n_ivl (lookup (S1 \<triangle> S2) x) < n_ivl (lookup S1 x)"
- using assms(2-5)
- by(auto simp: le_st_def narrow_st_def lookup_def intro: n_ivl_narrow
- split: if_splits)
- have "(\<Sum>x\<in>X. n_ivl(lookup (S1 \<triangle> S2) x)) < (\<Sum>x\<in>X. n_ivl(lookup S1 x))"
- apply(rule setsum_strict_mono1[OF `finite X`]) using 1 2 by blast+
- thus ?thesis by(simp add: n_st_def)
-qed
-
-
-subsubsection "Termination: Option"
-
-definition "m_o m n opt = (case opt of None \<Rightarrow> n+1 | Some x \<Rightarrow> m x)"
-
-lemma m_o_anti_mono: "finite X \<Longrightarrow> domo S2 \<subseteq> X \<Longrightarrow> S1 \<sqsubseteq> S2 \<Longrightarrow>
- m_o (m_st m_ivl) (2 * card X) S2 \<le> m_o (m_st m_ivl) (2 * card X) S1"
-apply(induction S1 S2 rule: le_option.induct)
-apply(auto simp: domo_def m_o_def m_st_anti_mono le_SucI m_st_height
- split: option.splits)
-done
-
-lemma m_o_widen: "\<lbrakk> finite X; domo S2 \<subseteq> X; \<not> S2 \<sqsubseteq> S1 \<rbrakk> \<Longrightarrow>
- m_o (m_st m_ivl) (2 * card X) (S1 \<nabla> S2) < m_o (m_st m_ivl) (2 * card X) S1"
-by(auto simp: m_o_def domo_def m_st_height less_Suc_eq_le m_st_widen
- split: option.split)
-
-definition "n_o n opt = (case opt of None \<Rightarrow> 0 | Some x \<Rightarrow> n x + 1)"
-
-lemma n_o_mono: "domo S1 \<subseteq> X \<Longrightarrow> domo S2 \<subseteq> X \<Longrightarrow> S1 \<sqsubseteq> S2 \<Longrightarrow>
- n_o (n_st n_ivl X) S1 \<le> n_o (n_st n_ivl X) S2"
-apply(induction S1 S2 rule: le_option.induct)
-apply(auto simp: domo_def n_o_def n_st_mono
- split: option.splits)
-done
-
-lemma n_o_narrow:
- "\<lbrakk> finite X; domo S1 \<subseteq> X; domo S2 \<subseteq> X; S2 \<sqsubseteq> S1; \<not> S1 \<sqsubseteq> S1 \<triangle> S2 \<rbrakk>
- \<Longrightarrow> n_o (n_st n_ivl X) (S1 \<triangle> S2) < n_o (n_st n_ivl X) S1"
-apply(induction S1 S2 rule: narrow_option.induct)
-apply(auto simp: n_o_def domo_def n_st_narrow)
-done
-
-lemma domo_widen_subset: "domo (S1 \<nabla> S2) \<subseteq> domo S1 \<union> domo S2"
-apply(induction S1 S2 rule: widen_option.induct)
-apply (auto simp: domo_def widen_st_def)
-done
-
-lemma domo_narrow_subset: "domo (S1 \<triangle> S2) \<subseteq> domo S1 \<union> domo S2"
-apply(induction S1 S2 rule: narrow_option.induct)
-apply (auto simp: domo_def narrow_st_def)
-done
-
-subsubsection "Termination: Commands"
-
-lemma strip_widen_acom[simp]:
- "strip c' = strip (c::'a::WN acom) \<Longrightarrow> strip (c \<nabla>\<^sub>c c') = strip c"
-by(induction "widen::'a\<Rightarrow>'a\<Rightarrow>'a" c c' rule: map2_acom.induct) simp_all
-
-lemma strip_narrow_acom[simp]:
- "strip c' = strip (c::'a::WN acom) \<Longrightarrow> strip (c \<triangle>\<^sub>c c') = strip c"
-by(induction "narrow::'a\<Rightarrow>'a\<Rightarrow>'a" c c' rule: map2_acom.induct) simp_all
-
-lemma annos_widen_acom[simp]: "strip c1 = strip (c2::'a::WN acom) \<Longrightarrow>
- annos(c1 \<nabla>\<^sub>c c2) = map (%(x,y).x\<nabla>y) (zip (annos c1) (annos(c2::'a::WN acom)))"
-by(induction "widen::'a\<Rightarrow>'a\<Rightarrow>'a" c1 c2 rule: map2_acom.induct)
- (simp_all add: size_annos_same2)
-
-lemma annos_narrow_acom[simp]: "strip c1 = strip (c2::'a::WN acom) \<Longrightarrow>
- annos(c1 \<triangle>\<^sub>c c2) = map (%(x,y).x\<triangle>y) (zip (annos c1) (annos(c2::'a::WN acom)))"
-by(induction "narrow::'a\<Rightarrow>'a\<Rightarrow>'a" c1 c2 rule: map2_acom.induct)
- (simp_all add: size_annos_same2)
-
-lemma widen_acom_Com[simp]: "strip c2 = strip c1 \<Longrightarrow>
- c1 : Com X \<Longrightarrow> c2 : Com X \<Longrightarrow> (c1 \<nabla>\<^sub>c c2) : Com X"
-apply(auto simp add: Com_def)
-apply(rename_tac S S' x)
-apply(erule in_set_zipE)
-apply(auto simp: domo_def split: option.splits)
-apply(case_tac S)
-apply(case_tac S')
-apply simp
-apply fastforce
-apply(case_tac S')
-apply fastforce
-apply (fastforce simp: widen_st_def)
-done
-
-lemma narrow_acom_Com[simp]: "strip c2 = strip c1 \<Longrightarrow>
- c1 : Com X \<Longrightarrow> c2 : Com X \<Longrightarrow> (c1 \<triangle>\<^sub>c c2) : Com X"
-apply(auto simp add: Com_def)
-apply(rename_tac S S' x)
-apply(erule in_set_zipE)
-apply(auto simp: domo_def split: option.splits)
-apply(case_tac S)
-apply(case_tac S')
-apply simp
-apply fastforce
-apply(case_tac S')
-apply fastforce
-apply (fastforce simp: narrow_st_def)
-done
-
-definition "m_c m c = (let as = annos c in \<Sum>i=0..<size as. m(as!i))"
-
-lemma measure_m_c: "finite X \<Longrightarrow> {(c, c \<nabla>\<^sub>c c') |c c'\<Colon>ivl st option acom.
- strip c' = strip c \<and> c : Com X \<and> c' : Com X \<and> \<not> c' \<sqsubseteq> c}\<inverse>
- \<subseteq> measure(m_c(m_o (m_st m_ivl) (2*card(X))))"
-apply(auto simp: m_c_def Let_def Com_def)
-apply(subgoal_tac "length(annos c') = length(annos c)")
-prefer 2 apply (simp add: size_annos_same2)
-apply (auto)
-apply(rule setsum_strict_mono1)
-apply simp
-apply (clarsimp)
-apply(erule m_o_anti_mono)
-apply(rule subset_trans[OF domo_widen_subset])
-apply fastforce
-apply(rule widen1)
-apply(auto simp: le_iff_le_annos listrel_iff_nth)
-apply(rule_tac x=n in bexI)
-prefer 2 apply simp
-apply(erule m_o_widen)
-apply (simp)+
-done
-
-lemma measure_n_c: "finite X \<Longrightarrow> {(c, c \<triangle>\<^sub>c c') |c c'.
- strip c = strip c' \<and> c \<in> Com X \<and> c' \<in> Com X \<and> c' \<sqsubseteq> c \<and> \<not> c \<sqsubseteq> c \<triangle>\<^sub>c c'}\<inverse>
- \<subseteq> measure(m_c(n_o (n_st n_ivl X)))"
-apply(auto simp: m_c_def Let_def Com_def)
-apply(subgoal_tac "length(annos c') = length(annos c)")
-prefer 2 apply (simp add: size_annos_same2)
-apply (auto)
-apply(rule setsum_strict_mono1)
-apply simp
-apply (clarsimp)
-apply(rule n_o_mono)
-using domo_narrow_subset apply fastforce
-apply fastforce
-apply(rule narrow2)
-apply(fastforce simp: le_iff_le_annos listrel_iff_nth)
-apply(auto simp: le_iff_le_annos listrel_iff_nth strip_narrow_acom)
-apply(rule_tac x=n in bexI)
-prefer 2 apply simp
-apply(erule n_o_narrow)
-apply (simp)+
-done
-
-
-subsubsection "Termination: Post-Fixed Point Iterations"
-
-lemma iter_widen_termination:
-fixes c0 :: "'a::WN acom"
-assumes P_f: "\<And>c. P c \<Longrightarrow> P(f c)"
-assumes P_widen: "\<And>c c'. P c \<Longrightarrow> P c' \<Longrightarrow> P(c \<nabla>\<^sub>c c')"
-and "wf({(c::'a acom,c \<nabla>\<^sub>c c')|c c'. P c \<and> P c' \<and> ~ c' \<sqsubseteq> c}^-1)"
-and "P c0" and "c0 \<sqsubseteq> f c0" shows "EX c. iter_widen f c0 = Some c"
-proof(simp add: iter_widen_def, rule wf_while_option_Some[where P = "P"])
- show "wf {(cc', c). (P c \<and> \<not> f c \<sqsubseteq> c) \<and> cc' = c \<nabla>\<^sub>c f c}"
- apply(rule wf_subset[OF assms(3)]) by(blast intro: P_f)
-next
- show "P c0" by(rule `P c0`)
-next
- fix c assume "P c" thus "P (c \<nabla>\<^sub>c f c)" by(simp add: P_f P_widen)
-qed
-
-lemma iter_narrow_termination:
-assumes P_f: "\<And>c. P c \<Longrightarrow> P(c \<triangle>\<^sub>c f c)"
-and wf: "wf({(c, c \<triangle>\<^sub>c f c)|c c'. P c \<and> ~ c \<sqsubseteq> c \<triangle>\<^sub>c f c}^-1)"
-and "P c0" shows "EX c. iter_narrow f c0 = Some c"
-proof(simp add: iter_narrow_def, rule wf_while_option_Some[where P = "P"])
- show "wf {(c', c). (P c \<and> \<not> c \<sqsubseteq> c \<triangle>\<^sub>c f c) \<and> c' = c \<triangle>\<^sub>c f c}"
- apply(rule wf_subset[OF wf]) by(blast intro: P_f)
-next
- show "P c0" by(rule `P c0`)
-next
- fix c assume "P c" thus "P (c \<triangle>\<^sub>c f c)" by(simp add: P_f)
-qed
-
-lemma iter_winden_step_ivl_termination:
- "EX c. iter_widen (step_ivl \<top>) (\<bottom>\<^sub>c c0) = Some c"
-apply(rule iter_widen_termination[where
- P = "%c. strip c = c0 \<and> c : Com(vars c0)"])
-apply (simp_all add: step'_Com bot_acom)
-apply(rule wf_subset)
-apply(rule wf_measure)
-apply(rule subset_trans)
-prefer 2
-apply(rule measure_m_c[where X = "vars c0", OF finite_cvars])
-apply blast
-done
-
-lemma iter_narrow_step_ivl_termination:
- "c0 \<in> Com (vars(strip c0)) \<Longrightarrow> step_ivl \<top> c0 \<sqsubseteq> c0 \<Longrightarrow>
- EX c. iter_narrow (step_ivl \<top>) c0 = Some c"
-apply(rule iter_narrow_termination[where
- P = "%c. strip c = strip c0 \<and> c : Com(vars(strip c0)) \<and> step_ivl \<top> c \<sqsubseteq> c"])
-apply (simp_all add: step'_Com)
-apply(clarify)
-apply(frule narrow2_acom, drule mono_step'[OF le_refl], erule le_trans[OF _ narrow1_acom])
-apply assumption
-apply(rule wf_subset)
-apply(rule wf_measure)
-apply(rule subset_trans)
-prefer 2
-apply(rule measure_n_c[where X = "vars(strip c0)", OF finite_cvars])
-apply auto
-by (metis bot_least domo_Top order_refl step'_Com strip_step')
-
-(* FIXME: simplify type system: Combine Com(X) and vars <= X?? *)
-lemma while_Com:
-fixes c :: "'a st option acom"
-assumes "while_option P f c = Some c'"
-and "!!c. strip(f c) = strip c"
-and "\<forall>c::'a st option acom. c : Com(X) \<longrightarrow> vars(strip c) \<subseteq> X \<longrightarrow> f c : Com(X)"
-and "c : Com(X)" and "vars(strip c) \<subseteq> X" shows "c' : Com(X)"
-using while_option_rule[where P = "\<lambda>c'. c' : Com(X) \<and> vars(strip c') \<subseteq> X", OF _ assms(1)]
-by(simp add: assms(2-))
-
-lemma iter_widen_Com: fixes f :: "'a::WN st option acom \<Rightarrow> 'a st option acom"
-assumes "iter_widen f c = Some c'"
-and "\<forall>c. c : Com(X) \<longrightarrow> vars(strip c) \<subseteq> X \<longrightarrow> f c : Com(X)"
-and "!!c. strip(f c) = strip c"
-and "c : Com(X)" and "vars (strip c) \<subseteq> X" shows "c' : Com(X)"
-proof-
- have "\<forall>c. c : Com(X) \<longrightarrow> vars(strip c) \<subseteq> X \<longrightarrow> c \<nabla>\<^sub>c f c : Com(X)"
- by (metis (full_types) widen_acom_Com assms(2,3))
- from while_Com[OF assms(1)[simplified iter_widen_def] _ this assms(4,5)]
- show ?thesis using assms(3) by(simp)
-qed
-
-
-context Abs_Int2
-begin
-
-lemma iter_widen_step'_Com:
- "iter_widen (step' \<top>) c = Some c' \<Longrightarrow> vars(strip c) \<subseteq> X \<Longrightarrow> c : Com(X)
- \<Longrightarrow> c' : Com(X)"
-apply(subgoal_tac "strip c'= strip c")
-prefer 2 apply (metis strip_iter_widen strip_step')
-apply(drule iter_widen_Com)
-prefer 3 apply assumption
-prefer 3 apply assumption
-apply (auto simp: step'_Com)
-done
-
-end
-
-theorem AI_ivl'_termination:
- "EX c'. AI_ivl' c = Some c'"
-apply(auto simp: AI_wn_def pfp_wn_def iter_winden_step_ivl_termination split: option.split)
-apply(rule iter_narrow_step_ivl_termination)
-apply (metis bot_acom_Com iter_widen_step'_Com[OF _ subset_refl] strip_iter_widen strip_step')
-apply(erule iter_widen_pfp)
-done
-
-end
-
-
-(* interesting(?) relic
-lemma widen_assoc:
- "~ (y::ivl) \<sqsubseteq> x \<Longrightarrow> ~ z \<sqsubseteq> x \<nabla> y \<Longrightarrow> ((x::ivl) \<nabla> y) \<nabla> z = x \<nabla> (y \<nabla> z)"
-apply(cases x)
-apply(cases y)
-apply(cases z)
-apply(rename_tac x1 x2 y1 y2 z1 z2)
-apply(simp add: le_ivl_def)
-apply(case_tac x1)
-apply(case_tac x2)
-apply(simp add:le_option_def widen_ivl_def split: if_splits option.splits)
-apply(simp add:le_option_def widen_ivl_def split: if_splits option.splits)
-apply(case_tac x2)
-apply(simp add:le_option_def widen_ivl_def split: if_splits option.splits)
-apply(case_tac y1)
-apply(case_tac y2)
-apply(simp add:le_option_def widen_ivl_def split: if_splits option.splits)
-apply(case_tac z1)
-apply(auto simp add:le_option_def widen_ivl_def split: if_splits option.splits ivl.splits)[1]
-apply(auto simp add:le_option_def widen_ivl_def split: if_splits option.splits ivl.splits)[1]
-apply(case_tac y2)
-apply(auto simp add:le_option_def widen_ivl_def split: if_splits option.splits ivl.splits)[1]
-apply(case_tac z1)
-apply(auto simp add:le_option_def widen_ivl_def split: if_splits ivl.splits option.splits)[1]
-apply(case_tac z2)
-apply(auto simp add:le_option_def widen_ivl_def split: if_splits option.splits)[1]
-apply(auto simp add:le_option_def widen_ivl_def split: if_splits option.splits)[1]
-done
-
-lemma widen_step_trans:
- "~ (y::ivl) \<sqsubseteq> x \<Longrightarrow> ~ z \<sqsubseteq> x \<nabla> y \<Longrightarrow> EX u. (x \<nabla> y) \<nabla> z = x \<nabla> u \<and> ~ u \<sqsubseteq> x"
-by (metis widen_assoc preord_class.le_trans widen1)
-*)