diff -r e5bfdd2d1ac8 -r a3b4eed091d2 prio/Attic/Prio.thy --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/prio/Attic/Prio.thy Sun Feb 05 21:00:12 2012 +0000 @@ -0,0 +1,2813 @@ +theory Prio +imports Precedence_ord Moment Lsp Happen_within +begin + +type_synonym thread = nat +type_synonym priority = nat +type_synonym cs = nat + +datatype event = + Create thread priority | + Exit thread | + P thread cs | + V thread cs | + Set thread priority + +datatype node = + Th "thread" | + Cs "cs" + +type_synonym state = "event list" + +fun threads :: "state \ thread set" +where + "threads [] = {}" | + "threads (Create thread prio#s) = {thread} \ threads s" | + "threads (Exit thread # s) = (threads s) - {thread}" | + "threads (e#s) = threads s" + +fun original_priority :: "thread \ state \ nat" +where + "original_priority thread [] = 0" | + "original_priority thread (Create thread' prio#s) = + (if thread' = thread then prio else original_priority thread s)" | + "original_priority thread (Set thread' prio#s) = + (if thread' = thread then prio else original_priority thread s)" | + "original_priority thread (e#s) = original_priority thread s" + +fun birthtime :: "thread \ state \ nat" +where + "birthtime thread [] = 0" | + "birthtime thread ((Create thread' prio)#s) = (if (thread = thread') then length s + else birthtime thread s)" | + "birthtime thread ((Set thread' prio)#s) = (if (thread = thread') then length s + else birthtime thread s)" | + "birthtime thread (e#s) = birthtime thread s" + +definition preced :: "thread \ state \ precedence" + where "preced thread s = Prc (original_priority thread s) (birthtime thread s)" + +consts holding :: "'b \ thread \ cs \ bool" + waiting :: "'b \ thread \ cs \ bool" + depend :: "'b \ (node \ node) set" + dependents :: "'b \ thread \ thread set" + +defs (overloaded) cs_holding_def: "holding wq thread cs == (thread \ set (wq cs) \ thread = hd (wq cs))" + cs_waiting_def: "waiting wq thread cs == (thread \ set (wq cs) \ thread \ hd (wq cs))" + cs_depend_def: "depend (wq::cs \ thread list) == {(Th t, Cs c) | t c. waiting wq t c} \ + {(Cs c, Th t) | c t. holding wq t c}" + cs_dependents_def: "dependents (wq::cs \ thread list) th == {th' . (Th th', Th th) \ (depend wq)^+}" + +record schedule_state = + waiting_queue :: "cs \ thread list" + cur_preced :: "thread \ precedence" + + +definition cpreced :: "state \ (cs \ thread list) \ thread \ precedence" +where "cpreced s wq = (\ th. Max ((\ th. preced th s) ` ({th} \ dependents wq th)))" + +fun schs :: "state \ schedule_state" +where + "schs [] = \waiting_queue = \ cs. [], + cur_preced = cpreced [] (\ cs. [])\" | + "schs (e#s) = (let ps = schs s in + let pwq = waiting_queue ps in + let pcp = cur_preced ps in + let nwq = case e of + P thread cs \ pwq(cs:=(pwq cs @ [thread])) | + V thread cs \ let nq = case (pwq cs) of + [] \ [] | + (th#pq) \ case (lsp pcp pq) of + (l, [], r) \ [] + | (l, m#ms, r) \ m#(l@ms@r) + in pwq(cs:=nq) | + _ \ pwq + in let ncp = cpreced (e#s) nwq in + \waiting_queue = nwq, cur_preced = ncp\ + )" + +definition wq :: "state \ cs \ thread list" +where "wq s == waiting_queue (schs s)" + +definition cp :: "state \ thread \ precedence" +where "cp s = cur_preced (schs s)" + +defs (overloaded) s_holding_def: "holding (s::state) thread cs == (thread \ set (wq s cs) \ thread = hd (wq s cs))" + s_waiting_def: "waiting (s::state) thread cs == (thread \ set (wq s cs) \ thread \ hd (wq s cs))" + s_depend_def: "depend (s::state) == {(Th t, Cs c) | t c. waiting (wq s) t c} \ + {(Cs c, Th t) | c t. holding (wq s) t c}" + s_dependents_def: "dependents (s::state) th == {th' . (Th th', Th th) \ (depend (wq s))^+}" + +definition readys :: "state \ thread set" +where + "readys s = + {thread . thread \ threads s \ (\ cs. \ waiting s thread cs)}" + +definition runing :: "state \ thread set" +where "runing s = {th . th \ readys s \ cp s th = Max ((cp s) ` (readys s))}" + +definition holdents :: "state \ thread \ cs set" + where "holdents s th = {cs . (Cs cs, Th th) \ depend s}" + +inductive step :: "state \ event \ bool" +where + thread_create: "\prio \ max_prio; thread \ threads s\ \ step s (Create thread prio)" | + thread_exit: "\thread \ runing s; holdents s thread = {}\ \ step s (Exit thread)" | + thread_P: "\thread \ runing s; (Cs cs, Th thread) \ (depend s)^+\ \ step s (P thread cs)" | + thread_V: "\thread \ runing s; holding s thread cs\ \ step s (V thread cs)" | + thread_set: "\thread \ runing s\ \ step s (Set thread prio)" + +inductive vt :: "(state \ event \ bool) \ state \ bool" + for cs +where + vt_nil[intro]: "vt cs []" | + vt_cons[intro]: "\vt cs s; cs s e\ \ vt cs (e#s)" + +lemma runing_ready: "runing s \ readys s" + by (auto simp only:runing_def readys_def) + +lemma wq_v_eq_nil: + fixes s cs thread rest + assumes eq_wq: "wq s cs = thread # rest" + and eq_lsp: "lsp (cp s) rest = (l, [], r)" + shows "wq (V thread cs#s) cs = []" +proof - + from prems show ?thesis + by (auto simp:wq_def Let_def cp_def split:list.splits) +qed + +lemma wq_v_eq: + fixes s cs thread rest + assumes eq_wq: "wq s cs = thread # rest" + and eq_lsp: "lsp (cp s) rest = (l, [th'], r)" + shows "wq (V thread cs#s) cs = th'#l@r" +proof - + from prems show ?thesis + by (auto simp:wq_def Let_def cp_def split:list.splits) +qed + +lemma wq_v_neq: + "cs \ cs' \ wq (V thread cs#s) cs' = wq s cs'" + by (auto simp:wq_def Let_def cp_def split:list.splits) + +lemma wq_distinct: "vt step s \ distinct (wq s cs)" +proof(erule_tac vt.induct, simp add:wq_def) + fix s e + assume h1: "step s e" + and h2: "distinct (wq s cs)" + thus "distinct (wq (e # s) cs)" + proof(induct rule:step.induct, auto simp: wq_def Let_def split:list.splits) + fix thread s + assume h1: "(Cs cs, Th thread) \ (depend s)\<^sup>+" + and h2: "thread \ set (waiting_queue (schs s) cs)" + and h3: "thread \ runing s" + show "False" + proof - + from h3 have "\ cs. thread \ set (waiting_queue (schs s) cs) \ + thread = hd ((waiting_queue (schs s) cs))" + by (simp add:runing_def readys_def s_waiting_def wq_def) + from this [OF h2] have "thread = hd (waiting_queue (schs s) cs)" . + with h2 + have "(Cs cs, Th thread) \ (depend s)" + by (simp add:s_depend_def s_holding_def wq_def cs_holding_def) + with h1 show False by auto + qed + next + fix thread s a list + assume h1: "thread \ runing s" + and h2: "holding s thread cs" + and h3: "waiting_queue (schs s) cs = a # list" + and h4: "a \ set list" + and h5: "distinct list" + thus "distinct + ((\(l, a, r). case a of [] \ [] | m # ms \ m # l @ ms @ r) + (lsp (cur_preced (schs s)) list))" + apply (cases "(lsp (cur_preced (schs s)) list)", simp) + apply (case_tac b, simp) + by (drule_tac lsp_set_eq, simp) + qed +qed + +lemma block_pre: + fixes thread cs s + assumes s_ni: "thread \ set (wq s cs)" + and s_i: "thread \ set (wq (e#s) cs)" + shows "e = P thread cs" +proof - + have ee: "\ x y. \x = y\ \ set x = set y" + by auto + from s_ni s_i show ?thesis + proof (cases e, auto split:if_splits simp add:Let_def wq_def) + fix uu uub uuc uud uue + assume h: "(uuc, thread # uu, uub) = lsp (cur_preced (schs s)) uud" + and h1 [symmetric]: "uue # uud = waiting_queue (schs s) cs" + and h2: "thread \ set (waiting_queue (schs s) cs)" + from lsp_set [OF h] have "set (uuc @ (thread # uu) @ uub) = set uud" . + hence "thread \ set uud" by auto + with h1 have "thread \ set (waiting_queue (schs s) cs)" by auto + with h2 show False by auto + next + fix uu uua uub uuc uud uue + assume h1: "thread \ set (waiting_queue (schs s) cs)" + and h2: "uue # uud = waiting_queue (schs s) cs" + and h3: "(uuc, uua # uu, uub) = lsp (cur_preced (schs s)) uud" + and h4: "thread \ set uuc" + from lsp_set [OF h3] have "set (uuc @ (uua # uu) @ uub) = set uud" . + with h4 have "thread \ set uud" by auto + with h2 have "thread \ set (waiting_queue (schs s) cs)" + apply (drule_tac ee) by auto + with h1 show "False" by fast + next + fix uu uua uub uuc uud uue + assume h1: "thread \ set (waiting_queue (schs s) cs)" + and h2: "uue # uud = waiting_queue (schs s) cs" + and h3: "(uuc, uua # uu, uub) = lsp (cur_preced (schs s)) uud" + and h4: "thread \ set uu" + from lsp_set [OF h3] have "set (uuc @ (uua # uu) @ uub) = set uud" . + with h4 have "thread \ set uud" by auto + with h2 have "thread \ set (waiting_queue (schs s) cs)" + apply (drule_tac ee) by auto + with h1 show "False" by fast + next + fix uu uua uub uuc uud uue + assume h1: "thread \ set (waiting_queue (schs s) cs)" + and h2: "uue # uud = waiting_queue (schs s) cs" + and h3: "(uuc, uua # uu, uub) = lsp (cur_preced (schs s)) uud" + and h4: "thread \ set uub" + from lsp_set [OF h3] have "set (uuc @ (uua # uu) @ uub) = set uud" . + with h4 have "thread \ set uud" by auto + with h2 have "thread \ set (waiting_queue (schs s) cs)" + apply (drule_tac ee) by auto + with h1 show "False" by fast + qed +qed + +lemma p_pre: "\vt step ((P thread cs)#s)\ \ + thread \ runing s \ (Cs cs, Th thread) \ (depend s)^+" +apply (ind_cases "vt step ((P thread cs)#s)") +apply (ind_cases "step s (P thread cs)") +by auto + +lemma abs1: + fixes e es + assumes ein: "e \ set es" + and neq: "hd es \ hd (es @ [x])" + shows "False" +proof - + from ein have "es \ []" by auto + then obtain e ess where "es = e # ess" by (cases es, auto) + with neq show ?thesis by auto +qed + +lemma q_head: "Q (hd es) \ hd es = hd [th\es . Q th]" + by (cases es, auto) + +inductive_cases evt_cons: "vt cs (a#s)" + +lemma abs2: + assumes vt: "vt step (e#s)" + and inq: "thread \ set (wq s cs)" + and nh: "thread = hd (wq s cs)" + and qt: "thread \ hd (wq (e#s) cs)" + and inq': "thread \ set (wq (e#s) cs)" + shows "False" +proof - + have ee: "\ uuc thread uu uub s list. (uuc, thread # uu, uub) = lsp (cur_preced (schs s)) list \ + lsp (cur_preced (schs s)) list = (uuc, thread # uu, uub) + " by simp + from prems show "False" + apply (cases e) + apply ((simp split:if_splits add:Let_def wq_def)[1])+ + apply (insert abs1, fast)[1] + apply ((simp split:if_splits add:Let_def)[1])+ + apply (simp split:if_splits list.splits add:Let_def wq_def) + apply (auto dest!:ee) + apply (drule_tac lsp_set_eq, simp) + apply (subgoal_tac "distinct (waiting_queue (schs s) cs)", simp, fold wq_def) + apply (rule_tac wq_distinct, auto) + apply (erule_tac evt_cons, auto) + apply (drule_tac lsp_set_eq, simp) + apply (subgoal_tac "distinct (wq s cs)", simp) + apply (rule_tac wq_distinct, auto) + apply (erule_tac evt_cons, auto) + apply (drule_tac lsp_set_eq, simp) + apply (subgoal_tac "distinct (wq s cs)", simp) + apply (rule_tac wq_distinct, auto) + apply (erule_tac evt_cons, auto) + apply (auto simp:wq_def Let_def split:if_splits prod.splits) + done +qed + +lemma vt_moment: "\ t. \vt cs s; t \ length s\ \ vt cs (moment t s)" +proof(induct s, simp) + fix a s t + assume h: "\t.\vt cs s; t \ length s\ \ vt cs (moment t s)" + and vt_a: "vt cs (a # s)" + and le_t: "t \ length (a # s)" + show "vt cs (moment t (a # s))" + proof(cases "t = length (a#s)") + case True + from True have "moment t (a#s) = a#s" by simp + with vt_a show ?thesis by simp + next + case False + with le_t have le_t1: "t \ length s" by simp + from vt_a have "vt cs s" + by (erule_tac evt_cons, simp) + from h [OF this le_t1] have "vt cs (moment t s)" . + moreover have "moment t (a#s) = moment t s" + proof - + from moment_app [OF le_t1, of "[a]"] + show ?thesis by simp + qed + ultimately show ?thesis by auto + qed +qed + +(* Wrong: + lemma \thread \ set (waiting_queue cs1 s); thread \ set (waiting_queue cs2 s)\ \ cs1 = cs2" +*) + +lemma waiting_unique_pre: + fixes cs1 cs2 s thread + assumes vt: "vt step s" + and h11: "thread \ set (wq s cs1)" + and h12: "thread \ hd (wq s cs1)" + assumes h21: "thread \ set (wq s cs2)" + and h22: "thread \ hd (wq s cs2)" + and neq12: "cs1 \ cs2" + shows "False" +proof - + let "?Q cs s" = "thread \ set (wq s cs) \ thread \ hd (wq s cs)" + from h11 and h12 have q1: "?Q cs1 s" by simp + from h21 and h22 have q2: "?Q cs2 s" by simp + have nq1: "\ ?Q cs1 []" by (simp add:wq_def) + have nq2: "\ ?Q cs2 []" by (simp add:wq_def) + from p_split [of "?Q cs1", OF q1 nq1] + obtain t1 where lt1: "t1 < length s" + and np1: "\(thread \ set (wq (moment t1 s) cs1) \ + thread \ hd (wq (moment t1 s) cs1))" + and nn1: "(\i'>t1. thread \ set (wq (moment i' s) cs1) \ + thread \ hd (wq (moment i' s) cs1))" by auto + from p_split [of "?Q cs2", OF q2 nq2] + obtain t2 where lt2: "t2 < length s" + and np2: "\(thread \ set (wq (moment t2 s) cs2) \ + thread \ hd (wq (moment t2 s) cs2))" + and nn2: "(\i'>t2. thread \ set (wq (moment i' s) cs2) \ + thread \ hd (wq (moment i' s) cs2))" by auto + show ?thesis + proof - + { + assume lt12: "t1 < t2" + let ?t3 = "Suc t2" + from lt2 have le_t3: "?t3 \ length s" by auto + from moment_plus [OF this] + obtain e where eq_m: "moment ?t3 s = e#moment t2 s" by auto + have "t2 < ?t3" by simp + from nn2 [rule_format, OF this] and eq_m + have h1: "thread \ set (wq (e#moment t2 s) cs2)" and + h2: "thread \ hd (wq (e#moment t2 s) cs2)" by auto + have vt_e: "vt step (e#moment t2 s)" + proof - + from vt_moment [OF vt le_t3] + have "vt step (moment ?t3 s)" . + with eq_m show ?thesis by simp + qed + have ?thesis + proof(cases "thread \ set (wq (moment t2 s) cs2)") + case True + from True and np2 have eq_th: "thread = hd (wq (moment t2 s) cs2)" + by auto + from abs2 [OF vt_e True eq_th h2 h1] + show ?thesis by auto + next + case False + from block_pre [OF False h1] + have "e = P thread cs2" . + with vt_e have "vt step ((P thread cs2)# moment t2 s)" by simp + from p_pre [OF this] have "thread \ runing (moment t2 s)" by simp + with runing_ready have "thread \ readys (moment t2 s)" by auto + with nn1 [rule_format, OF lt12] + show ?thesis by (simp add:readys_def s_waiting_def, auto) + qed + } moreover { + assume lt12: "t2 < t1" + let ?t3 = "Suc t1" + from lt1 have le_t3: "?t3 \ length s" by auto + from moment_plus [OF this] + obtain e where eq_m: "moment ?t3 s = e#moment t1 s" by auto + have lt_t3: "t1 < ?t3" by simp + from nn1 [rule_format, OF this] and eq_m + have h1: "thread \ set (wq (e#moment t1 s) cs1)" and + h2: "thread \ hd (wq (e#moment t1 s) cs1)" by auto + have vt_e: "vt step (e#moment t1 s)" + proof - + from vt_moment [OF vt le_t3] + have "vt step (moment ?t3 s)" . + with eq_m show ?thesis by simp + qed + have ?thesis + proof(cases "thread \ set (wq (moment t1 s) cs1)") + case True + from True and np1 have eq_th: "thread = hd (wq (moment t1 s) cs1)" + by auto + from abs2 [OF vt_e True eq_th h2 h1] + show ?thesis by auto + next + case False + from block_pre [OF False h1] + have "e = P thread cs1" . + with vt_e have "vt step ((P thread cs1)# moment t1 s)" by simp + from p_pre [OF this] have "thread \ runing (moment t1 s)" by simp + with runing_ready have "thread \ readys (moment t1 s)" by auto + with nn2 [rule_format, OF lt12] + show ?thesis by (simp add:readys_def s_waiting_def, auto) + qed + } moreover { + assume eqt12: "t1 = t2" + let ?t3 = "Suc t1" + from lt1 have le_t3: "?t3 \ length s" by auto + from moment_plus [OF this] + obtain e where eq_m: "moment ?t3 s = e#moment t1 s" by auto + have lt_t3: "t1 < ?t3" by simp + from nn1 [rule_format, OF this] and eq_m + have h1: "thread \ set (wq (e#moment t1 s) cs1)" and + h2: "thread \ hd (wq (e#moment t1 s) cs1)" by auto + have vt_e: "vt step (e#moment t1 s)" + proof - + from vt_moment [OF vt le_t3] + have "vt step (moment ?t3 s)" . + with eq_m show ?thesis by simp + qed + have ?thesis + proof(cases "thread \ set (wq (moment t1 s) cs1)") + case True + from True and np1 have eq_th: "thread = hd (wq (moment t1 s) cs1)" + by auto + from abs2 [OF vt_e True eq_th h2 h1] + show ?thesis by auto + next + case False + from block_pre [OF False h1] + have eq_e1: "e = P thread cs1" . + have lt_t3: "t1 < ?t3" by simp + with eqt12 have "t2 < ?t3" by simp + from nn2 [rule_format, OF this] and eq_m and eqt12 + have h1: "thread \ set (wq (e#moment t2 s) cs2)" and + h2: "thread \ hd (wq (e#moment t2 s) cs2)" by auto + show ?thesis + proof(cases "thread \ set (wq (moment t2 s) cs2)") + case True + from True and np2 have eq_th: "thread = hd (wq (moment t2 s) cs2)" + by auto + from vt_e and eqt12 have "vt step (e#moment t2 s)" by simp + from abs2 [OF this True eq_th h2 h1] + show ?thesis . + next + case False + from block_pre [OF False h1] + have "e = P thread cs2" . + with eq_e1 neq12 show ?thesis by auto + qed + qed + } ultimately show ?thesis by arith + qed +qed + +lemma waiting_unique: + assumes "vt step s" + and "waiting s th cs1" + and "waiting s th cs2" + shows "cs1 = cs2" +proof - + from waiting_unique_pre and prems + show ?thesis + by (auto simp add:s_waiting_def) +qed + +lemma holded_unique: + assumes "vt step s" + and "holding s th1 cs" + and "holding s th2 cs" + shows "th1 = th2" +proof - + from prems show ?thesis + unfolding s_holding_def + by auto +qed + +lemma birthtime_lt: "th \ threads s \ birthtime th s < length s" + apply (induct s, auto) + by (case_tac a, auto split:if_splits) + +lemma birthtime_unique: + "\birthtime th1 s = birthtime th2 s; th1 \ threads s; th2 \ threads s\ + \ th1 = th2" + apply (induct s, auto) + by (case_tac a, auto split:if_splits dest:birthtime_lt) + +lemma preced_unique : + assumes pcd_eq: "preced th1 s = preced th2 s" + and th_in1: "th1 \ threads s" + and th_in2: " th2 \ threads s" + shows "th1 = th2" +proof - + from pcd_eq have "birthtime th1 s = birthtime th2 s" by (simp add:preced_def) + from birthtime_unique [OF this th_in1 th_in2] + show ?thesis . +qed + +lemma preced_linorder: + assumes neq_12: "th1 \ th2" + and th_in1: "th1 \ threads s" + and th_in2: " th2 \ threads s" + shows "preced th1 s < preced th2 s \ preced th1 s > preced th2 s" +proof - + from preced_unique [OF _ th_in1 th_in2] and neq_12 + have "preced th1 s \ preced th2 s" by auto + thus ?thesis by auto +qed + +lemma unique_minus: + fixes x y z r + assumes unique: "\ a b c. \(a, b) \ r; (a, c) \ r\ \ b = c" + and xy: "(x, y) \ r" + and xz: "(x, z) \ r^+" + and neq: "y \ z" + shows "(y, z) \ r^+" +proof - + from xz and neq show ?thesis + proof(induct) + case (base ya) + have "(x, ya) \ r" by fact + from unique [OF xy this] have "y = ya" . + with base show ?case by auto + next + case (step ya z) + show ?case + proof(cases "y = ya") + case True + from step True show ?thesis by simp + next + case False + from step False + show ?thesis by auto + qed + qed +qed + +lemma unique_base: + fixes r x y z + assumes unique: "\ a b c. \(a, b) \ r; (a, c) \ r\ \ b = c" + and xy: "(x, y) \ r" + and xz: "(x, z) \ r^+" + and neq_yz: "y \ z" + shows "(y, z) \ r^+" +proof - + from xz neq_yz show ?thesis + proof(induct) + case (base ya) + from xy unique base show ?case by auto + next + case (step ya z) + show ?case + proof(cases "y = ya") + case True + from True step show ?thesis by auto + next + case False + from False step + have "(y, ya) \ r\<^sup>+" by auto + with step show ?thesis by auto + qed + qed +qed + +lemma unique_chain: + fixes r x y z + assumes unique: "\ a b c. \(a, b) \ r; (a, c) \ r\ \ b = c" + and xy: "(x, y) \ r^+" + and xz: "(x, z) \ r^+" + and neq_yz: "y \ z" + shows "(y, z) \ r^+ \ (z, y) \ r^+" +proof - + from xy xz neq_yz show ?thesis + proof(induct) + case (base y) + have h1: "(x, y) \ r" and h2: "(x, z) \ r\<^sup>+" and h3: "y \ z" using base by auto + from unique_base [OF _ h1 h2 h3] and unique show ?case by auto + next + case (step y za) + show ?case + proof(cases "y = z") + case True + from True step show ?thesis by auto + next + case False + from False step have "(y, z) \ r\<^sup>+ \ (z, y) \ r\<^sup>+" by auto + thus ?thesis + proof + assume "(z, y) \ r\<^sup>+" + with step have "(z, za) \ r\<^sup>+" by auto + thus ?thesis by auto + next + assume h: "(y, z) \ r\<^sup>+" + from step have yza: "(y, za) \ r" by simp + from step have "za \ z" by simp + from unique_minus [OF _ yza h this] and unique + have "(za, z) \ r\<^sup>+" by auto + thus ?thesis by auto + qed + qed + qed +qed + +lemma depend_set_unchanged: "(depend (Set th prio # s)) = depend s" +apply (unfold s_depend_def s_waiting_def wq_def) +by (simp add:Let_def) + +lemma depend_create_unchanged: "(depend (Create th prio # s)) = depend s" +apply (unfold s_depend_def s_waiting_def wq_def) +by (simp add:Let_def) + +lemma depend_exit_unchanged: "(depend (Exit th # s)) = depend s" +apply (unfold s_depend_def s_waiting_def wq_def) +by (simp add:Let_def) + +definition head_of :: "('a \ 'b::linorder) \ 'a set \ 'a set" + where "head_of f A = {a . a \ A \ f a = Max (f ` A)}" + +definition wq_head :: "state \ cs \ thread set" + where "wq_head s cs = head_of (cp s) (set (wq s cs))" + +lemma f_nil_simp: "\f cs = []\ \ f(cs:=[]) = f" +proof + fix x + assume h:"f cs = []" + show "(f(cs := [])) x = f x" + proof(cases "cs = x") + case True + with h show ?thesis by simp + next + case False + with h show ?thesis by simp + qed +qed + +lemma step_back_vt: "vt ccs (e#s) \ vt ccs s" + by(ind_cases "vt ccs (e#s)", simp) + +lemma step_back_step: "vt ccs (e#s) \ ccs s e" + by(ind_cases "vt ccs (e#s)", simp) + +lemma holding_nil: + "\wq s cs = []; holding (wq s) th cs\ \ False" + by (unfold cs_holding_def, auto) + +lemma waiting_kept_1: " + \vt step (V th cs#s); wq s cs = a # list; waiting ((wq s)(cs := ab # aa @ lista @ ca)) t c; + lsp (cp s) list = (aa, ab # lista, ca)\ + \ waiting (wq s) t c" + apply (drule_tac step_back_vt, drule_tac wq_distinct[of _ cs]) + apply(drule_tac lsp_set_eq) + by (unfold cs_waiting_def, auto split:if_splits) + +lemma waiting_kept_2: + "\a list t c aa ca. + \wq s cs = a # list; waiting ((wq s)(cs := [])) t c; lsp (cp s) list = (aa, [], ca)\ + \ waiting (wq s) t c" + apply(drule_tac lsp_set_eq) + by (unfold cs_waiting_def, auto split:if_splits) + + +lemma holding_nil_simp: "\holding ((wq s)(cs := [])) t c\ \ holding (wq s) t c" + by(unfold cs_holding_def, auto) + +lemma step_wq_elim: "\vt step (V th cs#s); wq s cs = a # list; a \ th\ \ False" + apply(drule_tac step_back_step) + apply(ind_cases "step s (V th cs)") + by(unfold s_holding_def, auto) + +lemma holding_cs_neq_simp: "c \ cs \ holding ((wq s)(cs := u)) t c = holding (wq s) t c" + by (unfold cs_holding_def, auto) + +lemma holding_th_neq_elim: + "\a list c t aa ca ab lista. + \\ holding (wq s) t c; holding ((wq s)(cs := ab # aa @ lista @ ca)) t c; + ab \ t\ + \ False" + by (unfold cs_holding_def, auto split:if_splits) + +lemma holding_nil_abs: + "\ holding ((wq s)(cs := [])) th cs" + by (unfold cs_holding_def, auto split:if_splits) + +lemma holding_abs: "\holding ((wq s)(cs := ab # aa @ lista @ c)) th cs; ab \ th\ + \ False" + by (unfold cs_holding_def, auto split:if_splits) + +lemma waiting_abs: "\ waiting ((wq s)(cs := t # l @ r)) t cs" + by (unfold cs_waiting_def, auto split:if_splits) + +lemma waiting_abs_1: + "\\ waiting ((wq s)(cs := [])) t c; waiting (wq s) t c; c \ cs\ + \ False" + by (unfold cs_waiting_def, auto split:if_splits) + +lemma waiting_abs_2: " + \\ waiting ((wq s)(cs := ab # aa @ lista @ ca)) t c; waiting (wq s) t c; + c \ cs\ + \ False" + by (unfold cs_waiting_def, auto split:if_splits) + +lemma waiting_abs_3: + "\wq s cs = a # list; \ waiting ((wq s)(cs := [])) t c; + waiting (wq s) t c; lsp (cp s) list = (aa, [], ca)\ + \ False" + apply(drule_tac lsp_mid_nil, simp) + by(unfold cs_waiting_def, auto split:if_splits) + +lemma waiting_simp: "c \ cs \ waiting ((wq s)(cs:=z)) t c = waiting (wq s) t c" + by(unfold cs_waiting_def, auto split:if_splits) + +lemma holding_cs_eq: + "\\ holding ((wq s)(cs := [])) t c; holding (wq s) t c\ \ c = cs" + by(unfold cs_holding_def, auto split:if_splits) + +lemma holding_cs_eq_1: + "\\ holding ((wq s)(cs := ab # aa @ lista @ ca)) t c; holding (wq s) t c\ + \ c = cs" + by(unfold cs_holding_def, auto split:if_splits) + +lemma holding_th_eq: + "\vt step (V th cs#s); wq s cs = a # list; \ holding ((wq s)(cs := [])) t c; holding (wq s) t c; + lsp (cp s) list = (aa, [], ca)\ + \ t = th" + apply(drule_tac lsp_mid_nil, simp) + apply(unfold cs_holding_def, auto split:if_splits) + apply(drule_tac step_back_step) + apply(ind_cases "step s (V th cs)") + by (unfold s_holding_def, auto split:if_splits) + +lemma holding_th_eq_1: + "\vt step (V th cs#s); + wq s cs = a # list; \ holding ((wq s)(cs := ab # aa @ lista @ ca)) t c; holding (wq s) t c; + lsp (cp s) list = (aa, ab # lista, ca)\ + \ t = th" + apply(drule_tac step_back_step) + apply(ind_cases "step s (V th cs)") + apply(unfold s_holding_def cs_holding_def) + by (auto split:if_splits) + +lemma holding_th_eq_2: "\holding ((wq s)(cs := ac # x)) th cs\ + \ ac = th" + by (unfold cs_holding_def, auto) + +lemma holding_th_eq_3: " + \\ holding (wq s) t c; + holding ((wq s)(cs := ac # x)) t c\ + \ ac = t" + by (unfold cs_holding_def, auto) + +lemma holding_wq_eq: "holding ((wq s)(cs := th' # l @ r)) th' cs" + by (unfold cs_holding_def, auto) + +lemma waiting_th_eq: " + \waiting (wq s) t c; wq s cs = a # list; + lsp (cp s) list = (aa, ac # lista, ba); \ waiting ((wq s)(cs := ac # aa @ lista @ ba)) t c\ + \ ac = t" + apply(drule_tac lsp_set_eq, simp) + by (unfold cs_waiting_def, auto split:if_splits) + +lemma step_depend_v: + "vt step (V th cs#s) \ + depend (V th cs # s) = + depend s - {(Cs cs, Th th)} - + {(Th th', Cs cs) |th'. \rest. wq s cs = th # rest \ (\l r. lsp (cp s) rest = (l, [th'], r))} \ + {(Cs cs, Th th') |th'. \rest. wq s cs = th # rest \ (\l r. lsp (cp s) rest = (l, [th'], r))}" + apply (unfold s_depend_def wq_def, + auto split:list.splits simp:Let_def f_nil_simp holding_wq_eq, fold wq_def cp_def) + apply (auto split:list.splits prod.splits + simp:Let_def f_nil_simp holding_nil_simp holding_cs_neq_simp holding_nil_abs + waiting_abs waiting_simp holding_wq_eq + elim:holding_nil waiting_kept_1 waiting_kept_2 step_wq_elim holding_th_neq_elim + holding_abs waiting_abs_1 waiting_abs_3 holding_cs_eq holding_cs_eq_1 + holding_th_eq holding_th_eq_1 holding_th_eq_2 holding_th_eq_3 waiting_th_eq + dest:lsp_mid_length) + done + +lemma step_depend_p: + "vt step (P th cs#s) \ + depend (P th cs # s) = (if (wq s cs = []) then depend s \ {(Cs cs, Th th)} + else depend s \ {(Th th, Cs cs)})" + apply(unfold s_depend_def wq_def) + apply (auto split:list.splits prod.splits simp:Let_def cs_waiting_def cs_holding_def) + apply(case_tac "c = cs", auto) + apply(fold wq_def) + apply(drule_tac step_back_step) + by (ind_cases " step s (P (hd (wq s cs)) cs)", + auto simp:s_depend_def wq_def cs_holding_def) + +lemma simple_A: + fixes A + assumes h: "\ x y. \x \ A; y \ A\ \ x = y" + shows "A = {} \ (\ a. A = {a})" +proof(cases "A = {}") + case True thus ?thesis by simp +next + case False then obtain a where "a \ A" by auto + with h have "A = {a}" by auto + thus ?thesis by simp +qed + +lemma depend_target_th: "(Th th, x) \ depend (s::state) \ \ cs. x = Cs cs" + by (unfold s_depend_def, auto) + +lemma acyclic_depend: + fixes s + assumes vt: "vt step s" + shows "acyclic (depend s)" +proof - + from vt show ?thesis + proof(induct) + case (vt_cons s e) + assume ih: "acyclic (depend s)" + and stp: "step s e" + and vt: "vt step s" + show ?case + proof(cases e) + case (Create th prio) + with ih + show ?thesis by (simp add:depend_create_unchanged) + next + case (Exit th) + with ih show ?thesis by (simp add:depend_exit_unchanged) + next + case (V th cs) + from V vt stp have vtt: "vt step (V th cs#s)" by auto + from step_depend_v [OF this] + have eq_de: "depend (e # s) = + depend s - {(Cs cs, Th th)} - + {(Th th', Cs cs) |th'. \rest. wq s cs = th # rest \ (\l r. lsp (cp s) rest = (l, [th'], r))} \ + {(Cs cs, Th th') |th'. \rest. wq s cs = th # rest \ (\l r. lsp (cp s) rest = (l, [th'], r))}" + (is "?L = (?A - ?B - ?C) \ ?D") by (simp add:V) + from ih have ac: "acyclic (?A - ?B - ?C)" by (auto elim:acyclic_subset) + have "?D = {} \ (\ a. ?D = {a})" by (rule simple_A, auto) + thus ?thesis + proof(cases "wq s cs") + case Nil + hence "?D = {}" by simp + with ac and eq_de show ?thesis by simp + next + case (Cons tth rest) + from stp and V have "step s (V th cs)" by simp + hence eq_wq: "wq s cs = th # rest" + proof - + show "step s (V th cs) \ wq s cs = th # rest" + apply(ind_cases "step s (V th cs)") + by(insert Cons, unfold s_holding_def, simp) + qed + show ?thesis + proof(cases "lsp (cp s) rest") + fix l b r + assume eq_lsp: "lsp (cp s) rest = (l, b, r) " + show ?thesis + proof(cases "b") + case Nil + with eq_lsp and eq_wq have "?D = {}" by simp + with ac and eq_de show ?thesis by simp + next + case (Cons th' m) + with eq_lsp + have eq_lsp: "lsp (cp s) rest = (l, [th'], r)" + apply simp + by (drule_tac lsp_mid_length, simp) + from eq_wq and eq_lsp + have eq_D: "?D = {(Cs cs, Th th')}" by auto + from eq_wq and eq_lsp + have eq_C: "?C = {(Th th', Cs cs)}" by auto + let ?E = "(?A - ?B - ?C)" + have "(Th th', Cs cs) \ ?E\<^sup>*" + proof + assume "(Th th', Cs cs) \ ?E\<^sup>*" + hence " (Th th', Cs cs) \ ?E\<^sup>+" by (simp add: rtrancl_eq_or_trancl) + from tranclD [OF this] + obtain x where th'_e: "(Th th', x) \ ?E" by blast + hence th_d: "(Th th', x) \ ?A" by simp + from depend_target_th [OF this] + obtain cs' where eq_x: "x = Cs cs'" by auto + with th_d have "(Th th', Cs cs') \ ?A" by simp + hence wt_th': "waiting s th' cs'" + unfolding s_depend_def s_waiting_def cs_waiting_def by simp + hence "cs' = cs" + proof(rule waiting_unique [OF vt]) + from eq_wq eq_lsp wq_distinct[OF vt, of cs] + show "waiting s th' cs" by(unfold s_waiting_def, auto dest:lsp_set_eq) + qed + with th'_e eq_x have "(Th th', Cs cs) \ ?E" by simp + with eq_C show "False" by simp + qed + with acyclic_insert[symmetric] and ac and eq_D + and eq_de show ?thesis by simp + qed + qed + qed + next + case (P th cs) + from P vt stp have vtt: "vt step (P th cs#s)" by auto + from step_depend_p [OF this] P + have "depend (e # s) = + (if wq s cs = [] then depend s \ {(Cs cs, Th th)} else + depend s \ {(Th th, Cs cs)})" (is "?L = ?R") + by simp + moreover have "acyclic ?R" + proof(cases "wq s cs = []") + case True + hence eq_r: "?R = depend s \ {(Cs cs, Th th)}" by simp + have "(Th th, Cs cs) \ (depend s)\<^sup>*" + proof + assume "(Th th, Cs cs) \ (depend s)\<^sup>*" + hence "(Th th, Cs cs) \ (depend s)\<^sup>+" by (simp add: rtrancl_eq_or_trancl) + from tranclD2 [OF this] + obtain x where "(x, Cs cs) \ depend s" by auto + with True show False by (auto simp:s_depend_def cs_waiting_def) + qed + with acyclic_insert ih eq_r show ?thesis by auto + next + case False + hence eq_r: "?R = depend s \ {(Th th, Cs cs)}" by simp + have "(Cs cs, Th th) \ (depend s)\<^sup>*" + proof + assume "(Cs cs, Th th) \ (depend s)\<^sup>*" + hence "(Cs cs, Th th) \ (depend s)\<^sup>+" by (simp add: rtrancl_eq_or_trancl) + moreover from step_back_step [OF vtt] have "step s (P th cs)" . + ultimately show False + proof - + show " \(Cs cs, Th th) \ (depend s)\<^sup>+; step s (P th cs)\ \ False" + by (ind_cases "step s (P th cs)", simp) + qed + qed + with acyclic_insert ih eq_r show ?thesis by auto + qed + ultimately show ?thesis by simp + next + case (Set thread prio) + with ih + thm depend_set_unchanged + show ?thesis by (simp add:depend_set_unchanged) + qed + next + case vt_nil + show "acyclic (depend ([]::state))" + by (auto simp: s_depend_def cs_waiting_def + cs_holding_def wq_def acyclic_def) + qed +qed + +lemma finite_depend: + fixes s + assumes vt: "vt step s" + shows "finite (depend s)" +proof - + from vt show ?thesis + proof(induct) + case (vt_cons s e) + assume ih: "finite (depend s)" + and stp: "step s e" + and vt: "vt step s" + show ?case + proof(cases e) + case (Create th prio) + with ih + show ?thesis by (simp add:depend_create_unchanged) + next + case (Exit th) + with ih show ?thesis by (simp add:depend_exit_unchanged) + next + case (V th cs) + from V vt stp have vtt: "vt step (V th cs#s)" by auto + from step_depend_v [OF this] + have eq_de: "depend (e # s) = + depend s - {(Cs cs, Th th)} - + {(Th th', Cs cs) |th'. \rest. wq s cs = th # rest \ (\l r. lsp (cp s) rest = (l, [th'], r))} \ + {(Cs cs, Th th') |th'. \rest. wq s cs = th # rest \ (\l r. lsp (cp s) rest = (l, [th'], r))}" + (is "?L = (?A - ?B - ?C) \ ?D") by (simp add:V) + moreover from ih have ac: "finite (?A - ?B - ?C)" by simp + moreover have "finite ?D" + proof - + have "?D = {} \ (\ a. ?D = {a})" by (rule simple_A, auto) + thus ?thesis + proof + assume h: "?D = {}" + show ?thesis by (unfold h, simp) + next + assume "\ a. ?D = {a}" + thus ?thesis by auto + qed + qed + ultimately show ?thesis by simp + next + case (P th cs) + from P vt stp have vtt: "vt step (P th cs#s)" by auto + from step_depend_p [OF this] P + have "depend (e # s) = + (if wq s cs = [] then depend s \ {(Cs cs, Th th)} else + depend s \ {(Th th, Cs cs)})" (is "?L = ?R") + by simp + moreover have "finite ?R" + proof(cases "wq s cs = []") + case True + hence eq_r: "?R = depend s \ {(Cs cs, Th th)}" by simp + with True and ih show ?thesis by auto + next + case False + hence "?R = depend s \ {(Th th, Cs cs)}" by simp + with False and ih show ?thesis by auto + qed + ultimately show ?thesis by auto + next + case (Set thread prio) + with ih + show ?thesis by (simp add:depend_set_unchanged) + qed + next + case vt_nil + show "finite (depend ([]::state))" + by (auto simp: s_depend_def cs_waiting_def + cs_holding_def wq_def acyclic_def) + qed +qed + +text {* Several useful lemmas *} + +thm wf_trancl +thm finite_acyclic_wf +thm finite_acyclic_wf_converse +thm wf_induct + + +lemma wf_dep_converse: + fixes s + assumes vt: "vt step s" + shows "wf ((depend s)^-1)" +proof(rule finite_acyclic_wf_converse) + from finite_depend [OF vt] + show "finite (depend s)" . +next + from acyclic_depend[OF vt] + show "acyclic (depend s)" . +qed + +lemma hd_np_in: "x \ set l \ hd l \ set l" +by (induct l, auto) + +lemma th_chasing: "(Th th, Cs cs) \ depend (s::state) \ \ th'. (Cs cs, Th th') \ depend s" + by (auto simp:s_depend_def s_holding_def cs_holding_def cs_waiting_def wq_def dest:hd_np_in) + +lemma wq_threads: + fixes s cs + assumes vt: "vt step s" + and h: "th \ set (wq s cs)" + shows "th \ threads s" +proof - + from vt and h show ?thesis + proof(induct arbitrary: th cs) + case (vt_cons s e) + assume ih: "\th cs. th \ set (wq s cs) \ th \ threads s" + and stp: "step s e" + and vt: "vt step s" + and h: "th \ set (wq (e # s) cs)" + show ?case + proof(cases e) + case (Create th' prio) + with ih h show ?thesis + by (auto simp:wq_def Let_def) + next + case (Exit th') + with stp ih h show ?thesis + apply (auto simp:wq_def Let_def) + apply (ind_cases "step s (Exit th')") + apply (auto simp:runing_def readys_def s_holding_def s_waiting_def holdents_def + s_depend_def s_holding_def cs_holding_def) + by (fold wq_def, auto) + next + case (V th' cs') + show ?thesis + proof(cases "cs' = cs") + case False + with h + show ?thesis + apply(unfold wq_def V, auto simp:Let_def V split:prod.splits, fold wq_def) + by (drule_tac ih, simp) + next + case True + from h + show ?thesis + proof(unfold V wq_def) + assume th_in: "th \ set (waiting_queue (schs (V th' cs' # s)) cs)" (is "th \ set ?l") + show "th \ threads (V th' cs' # s)" + proof(cases "cs = cs'") + case False + hence "?l = waiting_queue (schs s) cs" by (simp add:Let_def) + with th_in have " th \ set (wq s cs)" + by (fold wq_def, simp) + from ih [OF this] show ?thesis by simp + next + case True + show ?thesis + proof(cases "waiting_queue (schs s) cs'") + case Nil + with h V show ?thesis + apply (auto simp:wq_def Let_def split:if_splits) + by (fold wq_def, drule_tac ih, simp) + next + case (Cons a rest) + assume eq_wq: "waiting_queue (schs s) cs' = a # rest" + with h V show ?thesis + proof(cases "(lsp (cur_preced (schs s)) rest)", unfold V) + fix l m r + assume eq_lsp: "lsp (cur_preced (schs s)) rest = (l, m, r)" + and eq_wq: "waiting_queue (schs s) cs' = a # rest" + and th_in_set: "th \ set (wq (V th' cs' # s) cs)" + show ?thesis + proof(cases "m") + case Nil + with eq_lsp have "rest = []" using lsp_mid_nil by auto + with eq_wq have "waiting_queue (schs s) cs' = [a]" by simp + with h[unfolded V wq_def] True + show ?thesis + by (simp add:Let_def) + next + case (Cons b rb) + with lsp_mid_length[OF eq_lsp] have eq_m: "m = [b]" by auto + with eq_lsp have "lsp (cur_preced (schs s)) rest = (l, [b], r)" by simp + with h[unfolded V wq_def] True lsp_set_eq [OF this] eq_wq + show ?thesis + apply (auto simp:Let_def, fold wq_def) + by (rule_tac ih [of _ cs'], auto)+ + qed + qed + qed + qed + qed + qed + next + case (P th' cs') + from h stp + show ?thesis + apply (unfold P wq_def) + apply (auto simp:Let_def split:if_splits, fold wq_def) + apply (auto intro:ih) + apply(ind_cases "step s (P th' cs')") + by (unfold runing_def readys_def, auto) + next + case (Set thread prio) + with ih h show ?thesis + by (auto simp:wq_def Let_def) + qed + next + case vt_nil + thus ?case by (auto simp:wq_def) + qed +qed + +lemma range_in: "\vt step s; (Th th) \ Range (depend (s::state))\ \ th \ threads s" + apply(unfold s_depend_def cs_waiting_def cs_holding_def) + by (auto intro:wq_threads) + +lemma readys_v_eq: + fixes th thread cs rest + assumes neq_th: "th \ thread" + and eq_wq: "wq s cs = thread#rest" + and not_in: "th \ set rest" + shows "(th \ readys (V thread cs#s)) = (th \ readys s)" +proof - + from prems show ?thesis + apply (auto simp:readys_def) + apply (case_tac "cs = csa", simp add:s_waiting_def) + apply (erule_tac x = csa in allE) + apply (simp add:s_waiting_def wq_def Let_def split:if_splits) + apply (case_tac "csa = cs", simp) + apply (erule_tac x = cs in allE) + by (auto simp:s_waiting_def wq_def Let_def split:list.splits prod.splits + dest:lsp_set_eq) +qed + +lemma readys_v_eq_1: + fixes th thread cs rest + assumes neq_th: "th \ thread" + and eq_wq: "wq s cs = thread#rest" + and eq_lsp: "lsp (cp s) rest = (l, [th'], r)" + and neq_th': "th \ th'" + shows "(th \ readys (V thread cs#s)) = (th \ readys s)" +proof - + from prems show ?thesis + apply (auto simp:readys_def) + apply (case_tac "cs = csa", simp add:s_waiting_def) + apply (erule_tac x = cs in allE) + apply (simp add:s_waiting_def wq_def Let_def split:prod.splits list.splits) + apply (drule_tac lsp_mid_nil,simp, clarify, fold cp_def, clarsimp) + apply (frule_tac lsp_set_eq, simp) + apply (erule_tac x = csa in allE) + apply (subst (asm) (2) s_waiting_def, unfold wq_def) + apply (auto simp:Let_def split:list.splits prod.splits if_splits + dest:lsp_set_eq) + apply (unfold s_waiting_def) + apply (fold wq_def, clarsimp) + apply (clarsimp)+ + apply (case_tac "csa = cs", simp) + apply (erule_tac x = cs in allE, simp) + apply (unfold wq_def) + by (auto simp:Let_def split:list.splits prod.splits if_splits + dest:lsp_set_eq) +qed + +lemma readys_v_eq_2: + fixes th thread cs rest + assumes neq_th: "th \ thread" + and eq_wq: "wq s cs = thread#rest" + and eq_lsp: "lsp (cp s) rest = (l, [th'], r)" + and neq_th': "th = th'" + and vt: "vt step s" + shows "(th \ readys (V thread cs#s))" +proof - + from prems show ?thesis + apply (auto simp:readys_def) + apply (rule_tac wq_threads [of s _ cs], auto dest:lsp_set_eq) + apply (unfold s_waiting_def wq_def) + apply (auto simp:Let_def split:list.splits prod.splits if_splits + dest:lsp_set_eq lsp_mid_nil lsp_mid_length) + apply (fold cp_def, simp+, clarsimp) + apply (frule_tac lsp_set_eq, simp) + apply (fold wq_def) + apply (subgoal_tac "csa = cs", simp) + apply (rule_tac waiting_unique [of s th'], simp) + by (auto simp:s_waiting_def) +qed + +lemma chain_building: + assumes vt: "vt step s" + shows "node \ Domain (depend s) \ (\ th'. th' \ readys s \ (node, Th th') \ (depend s)^+)" +proof - + from wf_dep_converse [OF vt] + have h: "wf ((depend s)\)" . + show ?thesis + proof(induct rule:wf_induct [OF h]) + fix x + assume ih [rule_format]: + "\y. (y, x) \ (depend s)\ \ + y \ Domain (depend s) \ (\th'. th' \ readys s \ (y, Th th') \ (depend s)\<^sup>+)" + show "x \ Domain (depend s) \ (\th'. th' \ readys s \ (x, Th th') \ (depend s)\<^sup>+)" + proof + assume x_d: "x \ Domain (depend s)" + show "\th'. th' \ readys s \ (x, Th th') \ (depend s)\<^sup>+" + proof(cases x) + case (Th th) + from x_d Th obtain cs where x_in: "(Th th, Cs cs) \ depend s" by (auto simp:s_depend_def) + with Th have x_in_r: "(Cs cs, x) \ (depend s)^-1" by simp + from th_chasing [OF x_in] obtain th' where "(Cs cs, Th th') \ depend s" by blast + hence "Cs cs \ Domain (depend s)" by auto + from ih [OF x_in_r this] obtain th' + where th'_ready: " th' \ readys s" and cs_in: "(Cs cs, Th th') \ (depend s)\<^sup>+" by auto + have "(x, Th th') \ (depend s)\<^sup>+" using Th x_in cs_in by auto + with th'_ready show ?thesis by auto + next + case (Cs cs) + from x_d Cs obtain th' where th'_d: "(Th th', x) \ (depend s)^-1" by (auto simp:s_depend_def) + show ?thesis + proof(cases "th' \ readys s") + case True + from True and th'_d show ?thesis by auto + next + case False + from th'_d and range_in [OF vt] have "th' \ threads s" by auto + with False have "Th th' \ Domain (depend s)" + by (auto simp:readys_def s_waiting_def s_depend_def cs_waiting_def Domain_def) + from ih [OF th'_d this] + obtain th'' where + th''_r: "th'' \ readys s" and + th''_in: "(Th th', Th th'') \ (depend s)\<^sup>+" by auto + from th'_d and th''_in + have "(x, Th th'') \ (depend s)\<^sup>+" by auto + with th''_r show ?thesis by auto + qed + qed + qed + qed +qed + +lemma th_chain_to_ready: + fixes s th + assumes vt: "vt step s" + and th_in: "th \ threads s" + shows "th \ readys s \ (\ th'. th' \ readys s \ (Th th, Th th') \ (depend s)^+)" +proof(cases "th \ readys s") + case True + thus ?thesis by auto +next + case False + from False and th_in have "Th th \ Domain (depend s)" + by (auto simp:readys_def s_waiting_def s_depend_def cs_waiting_def Domain_def) + from chain_building [rule_format, OF vt this] + show ?thesis by auto +qed + +lemma waiting_eq: "waiting s th cs = waiting (wq s) th cs" + by (unfold s_waiting_def cs_waiting_def, auto) + +lemma holding_eq: "holding (s::state) th cs = holding (wq s) th cs" + by (unfold s_holding_def cs_holding_def, simp) + +lemma holding_unique: "\holding (s::state) th1 cs; holding s th2 cs\ \ th1 = th2" + by (unfold s_holding_def cs_holding_def, auto) + +lemma unique_depend: "\vt step s; (n, n1) \ depend s; (n, n2) \ depend s\ \ n1 = n2" + apply(unfold s_depend_def, auto, fold waiting_eq holding_eq) + by(auto elim:waiting_unique holding_unique) + +lemma trancl_split: "(a, b) \ r^+ \ \ c. (a, c) \ r" +by (induct rule:trancl_induct, auto) + +lemma dchain_unique: + assumes vt: "vt step s" + and th1_d: "(n, Th th1) \ (depend s)^+" + and th1_r: "th1 \ readys s" + and th2_d: "(n, Th th2) \ (depend s)^+" + and th2_r: "th2 \ readys s" + shows "th1 = th2" +proof - + { assume neq: "th1 \ th2" + hence "Th th1 \ Th th2" by simp + from unique_chain [OF _ th1_d th2_d this] and unique_depend [OF vt] + have "(Th th1, Th th2) \ (depend s)\<^sup>+ \ (Th th2, Th th1) \ (depend s)\<^sup>+" by auto + hence "False" + proof + assume "(Th th1, Th th2) \ (depend s)\<^sup>+" + from trancl_split [OF this] + obtain n where dd: "(Th th1, n) \ depend s" by auto + then obtain cs where eq_n: "n = Cs cs" + by (auto simp:s_depend_def s_holding_def cs_holding_def cs_waiting_def wq_def dest:hd_np_in) + from dd eq_n have "th1 \ readys s" + by (auto simp:readys_def s_depend_def s_waiting_def cs_waiting_def) + with th1_r show ?thesis by auto + next + assume "(Th th2, Th th1) \ (depend s)\<^sup>+" + from trancl_split [OF this] + obtain n where dd: "(Th th2, n) \ depend s" by auto + then obtain cs where eq_n: "n = Cs cs" + by (auto simp:s_depend_def s_holding_def cs_holding_def cs_waiting_def wq_def dest:hd_np_in) + from dd eq_n have "th2 \ readys s" + by (auto simp:readys_def s_depend_def s_waiting_def cs_waiting_def) + with th2_r show ?thesis by auto + qed + } thus ?thesis by auto +qed + +definition count :: "('a \ bool) \ 'a list \ nat" +where "count Q l = length (filter Q l)" + +definition cntP :: "state \ thread \ nat" +where "cntP s th = count (\ e. \ cs. e = P th cs) s" + +definition cntV :: "state \ thread \ nat" +where "cntV s th = count (\ e. \ cs. e = V th cs) s" + + +lemma step_holdents_p_add: + fixes th cs s + assumes vt: "vt step (P th cs#s)" + and "wq s cs = []" + shows "holdents (P th cs#s) th = holdents s th \ {cs}" +proof - + from prems show ?thesis + unfolding holdents_def step_depend_p[OF vt] by auto +qed + +lemma step_holdents_p_eq: + fixes th cs s + assumes vt: "vt step (P th cs#s)" + and "wq s cs \ []" + shows "holdents (P th cs#s) th = holdents s th" +proof - + from prems show ?thesis + unfolding holdents_def step_depend_p[OF vt] by auto +qed + +lemma step_holdents_v_minus: + fixes th cs s + assumes vt: "vt step (V th cs#s)" + shows "holdents (V th cs#s) th = holdents s th - {cs}" +proof - + { fix rest l r + assume eq_wq: "wq s cs = th # rest" + and eq_lsp: "lsp (cp s) rest = (l, [th], r)" + have "False" + proof - + from lsp_set_eq [OF eq_lsp] have " rest = l @ [th] @ r" . + with eq_wq have "wq s cs = th#\" by simp + with wq_distinct [OF step_back_vt[OF vt], of cs] + show ?thesis by auto + qed + } thus ?thesis unfolding holdents_def step_depend_v[OF vt] by auto +qed + +lemma step_holdents_v_add: + fixes th th' cs s rest l r + assumes vt: "vt step (V th' cs#s)" + and neq_th: "th \ th'" + and eq_wq: "wq s cs = th' # rest" + and eq_lsp: "lsp (cp s) rest = (l, [th], r)" + shows "holdents (V th' cs#s) th = holdents s th \ {cs}" +proof - + from prems show ?thesis + unfolding holdents_def step_depend_v[OF vt] by auto +qed + +lemma step_holdents_v_eq: + fixes th th' cs s rest l r th'' + assumes vt: "vt step (V th' cs#s)" + and neq_th: "th \ th'" + and eq_wq: "wq s cs = th' # rest" + and eq_lsp: "lsp (cp s) rest = (l, [th''], r)" + and neq_th': "th \ th''" + shows "holdents (V th' cs#s) th = holdents s th" +proof - + from prems show ?thesis + unfolding holdents_def step_depend_v[OF vt] by auto +qed + +definition cntCS :: "state \ thread \ nat" +where "cntCS s th = card (holdents s th)" + +lemma cntCS_v_eq: + fixes th thread cs rest + assumes neq_th: "th \ thread" + and eq_wq: "wq s cs = thread#rest" + and not_in: "th \ set rest" + and vtv: "vt step (V thread cs#s)" + shows "cntCS (V thread cs#s) th = cntCS s th" +proof - + from prems show ?thesis + apply (unfold cntCS_def holdents_def step_depend_v) + apply auto + apply (subgoal_tac "\ (\l r. lsp (cp s) rest = (l, [th], r))", auto) + by (drule_tac lsp_set_eq, auto) +qed + +lemma cntCS_v_eq_1: + fixes th thread cs rest + assumes neq_th: "th \ thread" + and eq_wq: "wq s cs = thread#rest" + and eq_lsp: "lsp (cp s) rest = (l, [th'], r)" + and neq_th': "th \ th'" + and vtv: "vt step (V thread cs#s)" + shows "cntCS (V thread cs#s) th = cntCS s th" +proof - + from prems show ?thesis + apply (unfold cntCS_def holdents_def step_depend_v) + by auto +qed + +fun the_cs :: "node \ cs" +where "the_cs (Cs cs) = cs" + +lemma cntCS_v_eq_2: + fixes th thread cs rest + assumes neq_th: "th \ thread" + and eq_wq: "wq s cs = thread#rest" + and eq_lsp: "lsp (cp s) rest = (l, [th'], r)" + and neq_th': "th = th'" + and vtv: "vt step (V thread cs#s)" + shows "cntCS (V thread cs#s) th = 1 + cntCS s th" +proof - + have "card {csa. csa = cs \ (Cs csa, Th th') \ depend s} = + Suc (card {cs. (Cs cs, Th th') \ depend s})" + (is "card ?A = Suc (card ?B)") + proof - + have h: "?A = insert cs ?B" by auto + moreover have h1: "?B = ?B - {cs}" + proof - + { assume "(Cs cs, Th th') \ depend s" + moreover have "(Th th', Cs cs) \ depend s" + proof - + from wq_distinct [OF step_back_vt[OF vtv], of cs] + eq_wq lsp_set_eq [OF eq_lsp] show ?thesis + apply (auto simp:s_depend_def) + by (unfold cs_waiting_def, auto) + qed + moreover note acyclic_depend [OF step_back_vt[OF vtv]] + ultimately have "False" + apply (auto simp:acyclic_def) + apply (erule_tac x="Cs cs" in allE) + apply (subgoal_tac "(Cs cs, Cs cs) \ (depend s)\<^sup>+", simp) + by (rule_tac trancl_into_trancl [where b = "Th th'"], auto) + } thus ?thesis by auto + qed + moreover have "card (insert cs ?B) = Suc (card (?B - {cs}))" + proof(rule card_insert) + from finite_depend [OF step_back_vt [OF vtv]] + have fnt: "finite (depend s)" . + show " finite {cs. (Cs cs, Th th') \ depend s}" (is "finite ?B") + proof - + have "?B \ (\ (a, b). the_cs a) ` (depend s)" + apply (auto simp:image_def) + by (rule_tac x = "(Cs x, Th th')" in bexI, auto) + with fnt show ?thesis by (auto intro:finite_subset) + qed + qed + ultimately show ?thesis by simp + qed + with prems show ?thesis + apply (unfold cntCS_def holdents_def step_depend_v[OF vtv]) + by auto +qed + +lemma finite_holding: + fixes s th cs + assumes vt: "vt step s" + shows "finite (holdents s th)" +proof - + let ?F = "\ (x, y). the_cs x" + from finite_depend [OF vt] + have "finite (depend s)" . + hence "finite (?F `(depend s))" by simp + moreover have "{cs . (Cs cs, Th th) \ depend s} \ \" + proof - + { have h: "\ a A f. a \ A \ f a \ f ` A" by auto + fix x assume "(Cs x, Th th) \ depend s" + hence "?F (Cs x, Th th) \ ?F `(depend s)" by (rule h) + moreover have "?F (Cs x, Th th) = x" by simp + ultimately have "x \ (\(x, y). the_cs x) ` depend s" by simp + } thus ?thesis by auto + qed + ultimately show ?thesis by (unfold holdents_def, auto intro:finite_subset) +qed + +inductive_cases case_step_v: "step s (V thread cs)" + +lemma cntCS_v_dec: + fixes s thread cs + assumes vtv: "vt step (V thread cs#s)" + shows "(cntCS (V thread cs#s) thread + 1) = cntCS s thread" +proof - + have cs_in: "cs \ holdents s thread" using step_back_step[OF vtv] + apply (erule_tac case_step_v) + apply (unfold holdents_def s_depend_def, simp) + by (unfold cs_holding_def s_holding_def, auto) + moreover have cs_not_in: + "(holdents (V thread cs#s) thread) = holdents s thread - {cs}" + apply (insert wq_distinct[OF step_back_vt[OF vtv], of cs]) + by (unfold holdents_def, unfold step_depend_v[OF vtv], + auto dest:lsp_set_eq) + ultimately + have "holdents s thread = insert cs (holdents (V thread cs#s) thread)" + by auto + moreover have "card \ = + Suc (card ((holdents (V thread cs#s) thread) - {cs}))" + proof(rule card_insert) + from finite_holding [OF vtv] + show " finite (holdents (V thread cs # s) thread)" . + qed + moreover from cs_not_in + have "cs \ (holdents (V thread cs#s) thread)" by auto + ultimately show ?thesis by (simp add:cntCS_def) +qed + +lemma cnp_cnv_cncs: + fixes s th + assumes vt: "vt step s" + shows "cntP s th = cntV s th + (if (th \ readys s \ th \ threads s) + then cntCS s th else cntCS s th + 1)" +proof - + from vt show ?thesis + proof(induct arbitrary:th) + case (vt_cons s e) + assume vt: "vt step s" + and ih: "\th. cntP s th = cntV s th + + (if (th \ readys s \ th \ threads s) then cntCS s th else cntCS s th + 1)" + and stp: "step s e" + from stp show ?case + proof(cases) + case (thread_create prio max_prio thread) + assume eq_e: "e = Create thread prio" + and not_in: "thread \ threads s" + show ?thesis + proof - + { fix cs + assume "thread \ set (wq s cs)" + from wq_threads [OF vt this] have "thread \ threads s" . + with not_in have "False" by simp + } with eq_e have eq_readys: "readys (e#s) = readys s \ {thread}" + by (auto simp:readys_def threads.simps s_waiting_def + wq_def cs_waiting_def Let_def) + from eq_e have eq_cnp: "cntP (e#s) th = cntP s th" by (simp add:cntP_def count_def) + from eq_e have eq_cnv: "cntV (e#s) th = cntV s th" by (simp add:cntV_def count_def) + have eq_cncs: "cntCS (e#s) th = cntCS s th" + unfolding cntCS_def holdents_def + by (simp add:depend_create_unchanged eq_e) + { assume "th \ thread" + with eq_readys eq_e + have "(th \ readys (e # s) \ th \ threads (e # s)) = + (th \ readys (s) \ th \ threads (s))" + by (simp add:threads.simps) + with eq_cnp eq_cnv eq_cncs ih not_in + have ?thesis by simp + } moreover { + assume eq_th: "th = thread" + with not_in ih have " cntP s th = cntV s th + cntCS s th" by simp + moreover from eq_th and eq_readys have "th \ readys (e#s)" by simp + moreover note eq_cnp eq_cnv eq_cncs + ultimately have ?thesis by auto + } ultimately show ?thesis by blast + qed + next + case (thread_exit thread) + assume eq_e: "e = Exit thread" + and is_runing: "thread \ runing s" + and no_hold: "holdents s thread = {}" + from eq_e have eq_cnp: "cntP (e#s) th = cntP s th" by (simp add:cntP_def count_def) + from eq_e have eq_cnv: "cntV (e#s) th = cntV s th" by (simp add:cntV_def count_def) + have eq_cncs: "cntCS (e#s) th = cntCS s th" + unfolding cntCS_def holdents_def + by (simp add:depend_exit_unchanged eq_e) + { assume "th \ thread" + with eq_e + have "(th \ readys (e # s) \ th \ threads (e # s)) = + (th \ readys (s) \ th \ threads (s))" + apply (simp add:threads.simps readys_def) + apply (subst s_waiting_def) + apply (subst (1 2) wq_def) + apply (simp add:Let_def) + apply (subst s_waiting_def, simp) + by (fold wq_def, simp) + with eq_cnp eq_cnv eq_cncs ih + have ?thesis by simp + } moreover { + assume eq_th: "th = thread" + with ih is_runing have " cntP s th = cntV s th + cntCS s th" + by (simp add:runing_def) + moreover from eq_th eq_e have "th \ threads (e#s)" + by simp + moreover note eq_cnp eq_cnv eq_cncs + ultimately have ?thesis by auto + } ultimately show ?thesis by blast + next + case (thread_P thread cs) + assume eq_e: "e = P thread cs" + and is_runing: "thread \ runing s" + and no_dep: "(Cs cs, Th thread) \ (depend s)\<^sup>+" + from prems have vtp: "vt step (P thread cs#s)" by auto + show ?thesis + proof - + { have hh: "\ A B C. (B = C) \ (A \ B) = (A \ C)" by blast + assume neq_th: "th \ thread" + with eq_e + have eq_readys: "(th \ readys (e#s)) = (th \ readys (s))" + apply (simp add:readys_def s_waiting_def wq_def Let_def) + apply (rule_tac hh, clarify) + apply (intro iffI allI, clarify) + apply (erule_tac x = csa in allE, auto) + apply (subgoal_tac "waiting_queue (schs s) cs \ []", auto) + apply (erule_tac x = cs in allE, auto) + by (case_tac "(waiting_queue (schs s) cs)", auto) + moreover from neq_th eq_e have "cntCS (e # s) th = cntCS s th" + apply (simp add:cntCS_def holdents_def) + by (unfold step_depend_p [OF vtp], auto) + moreover from eq_e neq_th have "cntP (e # s) th = cntP s th" + by (simp add:cntP_def count_def) + moreover from eq_e neq_th have "cntV (e#s) th = cntV s th" + by (simp add:cntV_def count_def) + moreover from eq_e neq_th have "threads (e#s) = threads s" by simp + moreover note ih [of th] + ultimately have ?thesis by simp + } moreover { + assume eq_th: "th = thread" + have ?thesis + proof - + from eq_e eq_th have eq_cnp: "cntP (e # s) th = 1 + (cntP s th)" + by (simp add:cntP_def count_def) + from eq_e eq_th have eq_cnv: "cntV (e#s) th = cntV s th" + by (simp add:cntV_def count_def) + show ?thesis + proof (cases "wq s cs = []") + case True + with is_runing + have "th \ readys (e#s)" + apply (unfold eq_e wq_def, unfold readys_def s_depend_def) + apply (simp add: wq_def[symmetric] runing_def eq_th s_waiting_def) + by (auto simp:readys_def wq_def Let_def s_waiting_def wq_def) + moreover have "cntCS (e # s) th = 1 + cntCS s th" + proof - + have "card {csa. csa = cs \ (Cs csa, Th thread) \ depend s} = + Suc (card {cs. (Cs cs, Th thread) \ depend s})" (is "card ?L = Suc (card ?R)") + proof - + have "?L = insert cs ?R" by auto + moreover have "card \ = Suc (card (?R - {cs}))" + proof(rule card_insert) + from finite_holding [OF vt, of thread] + show " finite {cs. (Cs cs, Th thread) \ depend s}" + by (unfold holdents_def, simp) + qed + moreover have "?R - {cs} = ?R" + proof - + have "cs \ ?R" + proof + assume "cs \ {cs. (Cs cs, Th thread) \ depend s}" + with no_dep show False by auto + qed + thus ?thesis by auto + qed + ultimately show ?thesis by auto + qed + thus ?thesis + apply (unfold eq_e eq_th cntCS_def) + apply (simp add: holdents_def) + by (unfold step_depend_p [OF vtp], auto simp:True) + qed + moreover from is_runing have "th \ readys s" + by (simp add:runing_def eq_th) + moreover note eq_cnp eq_cnv ih [of th] + ultimately show ?thesis by auto + next + case False + have eq_wq: "wq (e#s) cs = wq s cs @ [th]" + by (unfold eq_th eq_e wq_def, auto simp:Let_def) + have "th \ readys (e#s)" + proof + assume "th \ readys (e#s)" + hence "\cs. \ waiting (e # s) th cs" by (simp add:readys_def) + from this[rule_format, of cs] have " \ waiting (e # s) th cs" . + hence "th \ set (wq (e#s) cs) \ th = hd (wq (e#s) cs)" + by (simp add:s_waiting_def) + moreover from eq_wq have "th \ set (wq (e#s) cs)" by auto + ultimately have "th = hd (wq (e#s) cs)" by blast + with eq_wq have "th = hd (wq s cs @ [th])" by simp + hence "th = hd (wq s cs)" using False by auto + with False eq_wq wq_distinct [OF vtp, of cs] + show False by (fold eq_e, auto) + qed + moreover from is_runing have "th \ threads (e#s)" + by (unfold eq_e, auto simp:runing_def readys_def eq_th) + moreover have "cntCS (e # s) th = cntCS s th" + apply (unfold cntCS_def holdents_def eq_e step_depend_p[OF vtp]) + by (auto simp:False) + moreover note eq_cnp eq_cnv ih[of th] + moreover from is_runing have "th \ readys s" + by (simp add:runing_def eq_th) + ultimately show ?thesis by auto + qed + qed + } ultimately show ?thesis by blast + qed + next + case (thread_V thread cs) + from prems have vtv: "vt step (V thread cs # s)" by auto + assume eq_e: "e = V thread cs" + and is_runing: "thread \ runing s" + and hold: "holding s thread cs" + from hold obtain rest + where eq_wq: "wq s cs = thread # rest" + by (case_tac "wq s cs", auto simp:s_holding_def) + have eq_threads: "threads (e#s) = threads s" by (simp add: eq_e) + show ?thesis + proof - + { assume eq_th: "th = thread" + from eq_th have eq_cnp: "cntP (e # s) th = cntP s th" + by (unfold eq_e, simp add:cntP_def count_def) + moreover from eq_th have eq_cnv: "cntV (e#s) th = 1 + cntV s th" + by (unfold eq_e, simp add:cntV_def count_def) + moreover from cntCS_v_dec [OF vtv] + have "cntCS (e # s) thread + 1 = cntCS s thread" + by (simp add:eq_e) + moreover from is_runing have rd_before: "thread \ readys s" + by (unfold runing_def, simp) + moreover have "thread \ readys (e # s)" + proof - + from is_runing + have "thread \ threads (e#s)" + by (unfold eq_e, auto simp:runing_def readys_def) + moreover have "\ cs1. \ waiting (e#s) thread cs1" + proof + fix cs1 + { assume eq_cs: "cs1 = cs" + have "\ waiting (e # s) thread cs1" + proof - + have "thread \ set (wq (e#s) cs1)" + proof(cases "lsp (cp s) rest") + fix l m r + assume h: "lsp (cp s) rest = (l, m, r)" + show ?thesis + proof(cases "m") + case Nil + from wq_v_eq_nil [OF eq_wq] h Nil eq_e + have " wq (e # s) cs = []" by auto + thus ?thesis using eq_cs by auto + next + case (Cons th' l') + from lsp_mid_length [OF h] and Cons h + have eqh: "lsp (cp s) rest = (l, [th'], r)" by auto + from wq_v_eq [OF eq_wq this] + have "wq (V thread cs # s) cs = th' # l @ r" . + moreover from lsp_set_eq [OF eqh] + have "set rest = set \" by auto + moreover have "thread \ set rest" + proof - + from wq_distinct [OF step_back_vt[OF vtv], of cs] + and eq_wq show ?thesis by auto + qed + moreover note eq_e eq_cs + ultimately show ?thesis by simp + qed + qed + thus ?thesis by (simp add:s_waiting_def) + qed + } moreover { + assume neq_cs: "cs1 \ cs" + have "\ waiting (e # s) thread cs1" + proof - + from wq_v_neq [OF neq_cs[symmetric]] + have "wq (V thread cs # s) cs1 = wq s cs1" . + moreover have "\ waiting s thread cs1" + proof - + from runing_ready and is_runing + have "thread \ readys s" by auto + thus ?thesis by (simp add:readys_def) + qed + ultimately show ?thesis + by (auto simp:s_waiting_def eq_e) + qed + } ultimately show "\ waiting (e # s) thread cs1" by blast + qed + ultimately show ?thesis by (simp add:readys_def) + qed + moreover note eq_th ih + ultimately have ?thesis by auto + } moreover { + assume neq_th: "th \ thread" + from neq_th eq_e have eq_cnp: "cntP (e # s) th = cntP s th" + by (simp add:cntP_def count_def) + from neq_th eq_e have eq_cnv: "cntV (e # s) th = cntV s th" + by (simp add:cntV_def count_def) + have ?thesis + proof(cases "th \ set rest") + case False + have "(th \ readys (e # s)) = (th \ readys s)" + by(unfold eq_e, rule readys_v_eq [OF neq_th eq_wq False]) + moreover have "cntCS (e#s) th = cntCS s th" + by(unfold eq_e, rule cntCS_v_eq [OF neq_th eq_wq False vtv]) + moreover note ih eq_cnp eq_cnv eq_threads + ultimately show ?thesis by auto + next + case True + obtain l m r where eq_lsp: "lsp (cp s) rest = (l, m, r)" + by (cases "lsp (cp s) rest", auto) + with True have "m \ []" by (auto dest:lsp_mid_nil) + with eq_lsp obtain th' where eq_lsp: "lsp (cp s) rest = (l, [th'], r)" + by (case_tac m, auto dest:lsp_mid_length) + show ?thesis + proof(cases "th = th'") + case False + have "(th \ readys (e # s)) = (th \ readys s)" + by (unfold eq_e, rule readys_v_eq_1 [OF neq_th eq_wq eq_lsp False]) + moreover have "cntCS (e#s) th = cntCS s th" + by (unfold eq_e, rule cntCS_v_eq_1[OF neq_th eq_wq eq_lsp False vtv]) + moreover note ih eq_cnp eq_cnv eq_threads + ultimately show ?thesis by auto + next + case True + have "th \ readys (e # s)" + by (unfold eq_e, rule readys_v_eq_2 [OF neq_th eq_wq eq_lsp True vt]) + moreover have "cntP s th = cntV s th + cntCS s th + 1" + proof - + have "th \ readys s" + proof - + from True eq_wq lsp_set_eq [OF eq_lsp] neq_th + show ?thesis + apply (unfold readys_def s_waiting_def, auto) + by (rule_tac x = cs in exI, auto) + qed + moreover have "th \ threads s" + proof - + from True eq_wq lsp_set_eq [OF eq_lsp] neq_th + have "th \ set (wq s cs)" by simp + from wq_threads [OF step_back_vt[OF vtv] this] + show ?thesis . + qed + ultimately show ?thesis using ih by auto + qed + moreover have "cntCS (e # s) th = 1 + cntCS s th" + by (unfold eq_e, rule cntCS_v_eq_2 [OF neq_th eq_wq eq_lsp True vtv]) + moreover note eq_cnp eq_cnv + ultimately show ?thesis by simp + qed + qed + } ultimately show ?thesis by blast + qed + next + case (thread_set thread prio) + assume eq_e: "e = Set thread prio" + and is_runing: "thread \ runing s" + show ?thesis + proof - + from eq_e have eq_cnp: "cntP (e#s) th = cntP s th" by (simp add:cntP_def count_def) + from eq_e have eq_cnv: "cntV (e#s) th = cntV s th" by (simp add:cntV_def count_def) + have eq_cncs: "cntCS (e#s) th = cntCS s th" + unfolding cntCS_def holdents_def + by (simp add:depend_set_unchanged eq_e) + from eq_e have eq_readys: "readys (e#s) = readys s" + by (simp add:readys_def cs_waiting_def s_waiting_def wq_def, + auto simp:Let_def) + { assume "th \ thread" + with eq_readys eq_e + have "(th \ readys (e # s) \ th \ threads (e # s)) = + (th \ readys (s) \ th \ threads (s))" + by (simp add:threads.simps) + with eq_cnp eq_cnv eq_cncs ih is_runing + have ?thesis by simp + } moreover { + assume eq_th: "th = thread" + with is_runing ih have " cntP s th = cntV s th + cntCS s th" + by (unfold runing_def, auto) + moreover from eq_th and eq_readys is_runing have "th \ readys (e#s)" + by (simp add:runing_def) + moreover note eq_cnp eq_cnv eq_cncs + ultimately have ?thesis by auto + } ultimately show ?thesis by blast + qed + qed + next + case vt_nil + show ?case + by (unfold cntP_def cntV_def cntCS_def, + auto simp:count_def holdents_def s_depend_def wq_def cs_holding_def) + qed +qed + +lemma not_thread_cncs: + fixes th s + assumes vt: "vt step s" + and not_in: "th \ threads s" + shows "cntCS s th = 0" +proof - + from vt not_in show ?thesis + proof(induct arbitrary:th) + case (vt_cons s e th) + assume vt: "vt step s" + and ih: "\th. th \ threads s \ cntCS s th = 0" + and stp: "step s e" + and not_in: "th \ threads (e # s)" + from stp show ?case + proof(cases) + case (thread_create prio max_prio thread) + assume eq_e: "e = Create thread prio" + and not_in': "thread \ threads s" + have "cntCS (e # s) th = cntCS s th" + apply (unfold eq_e cntCS_def holdents_def) + by (simp add:depend_create_unchanged) + moreover have "th \ threads s" + proof - + from not_in eq_e show ?thesis by simp + qed + moreover note ih ultimately show ?thesis by auto + next + case (thread_exit thread) + assume eq_e: "e = Exit thread" + and nh: "holdents s thread = {}" + have eq_cns: "cntCS (e # s) th = cntCS s th" + apply (unfold eq_e cntCS_def holdents_def) + by (simp add:depend_exit_unchanged) + show ?thesis + proof(cases "th = thread") + case True + have "cntCS s th = 0" by (unfold cntCS_def, auto simp:nh True) + with eq_cns show ?thesis by simp + next + case False + with not_in and eq_e + have "th \ threads s" by simp + from ih[OF this] and eq_cns show ?thesis by simp + qed + next + case (thread_P thread cs) + assume eq_e: "e = P thread cs" + and is_runing: "thread \ runing s" + from prems have vtp: "vt step (P thread cs#s)" by auto + have neq_th: "th \ thread" + proof - + from not_in eq_e have "th \ threads s" by simp + moreover from is_runing have "thread \ threads s" + by (simp add:runing_def readys_def) + ultimately show ?thesis by auto + qed + hence "cntCS (e # s) th = cntCS s th " + apply (unfold cntCS_def holdents_def eq_e) + by (unfold step_depend_p[OF vtp], auto) + moreover have "cntCS s th = 0" + proof(rule ih) + from not_in eq_e show "th \ threads s" by simp + qed + ultimately show ?thesis by simp + next + case (thread_V thread cs) + assume eq_e: "e = V thread cs" + and is_runing: "thread \ runing s" + and hold: "holding s thread cs" + have neq_th: "th \ thread" + proof - + from not_in eq_e have "th \ threads s" by simp + moreover from is_runing have "thread \ threads s" + by (simp add:runing_def readys_def) + ultimately show ?thesis by auto + qed + from prems have vtv: "vt step (V thread cs#s)" by auto + from hold obtain rest + where eq_wq: "wq s cs = thread # rest" + by (case_tac "wq s cs", auto simp:s_holding_def) + have "cntCS (e # s) th = cntCS s th" + proof(unfold eq_e, rule cntCS_v_eq [OF neq_th eq_wq _ vtv]) + show "th \ set rest" + proof + assume "th \ set rest" + with eq_wq have "th \ set (wq s cs)" by simp + from wq_threads [OF vt this] eq_e not_in + show False by simp + qed + qed + moreover have "cntCS s th = 0" + proof(rule ih) + from not_in eq_e show "th \ threads s" by simp + qed + ultimately show ?thesis by simp + next + case (thread_set thread prio) + print_facts + assume eq_e: "e = Set thread prio" + and is_runing: "thread \ runing s" + from not_in and eq_e have "th \ threads s" by auto + from ih [OF this] and eq_e + show ?thesis + apply (unfold eq_e cntCS_def holdents_def) + by (simp add:depend_set_unchanged) + qed + next + case vt_nil + show ?case + by (unfold cntCS_def, + auto simp:count_def holdents_def s_depend_def wq_def cs_holding_def) + qed +qed + +lemma eq_waiting: "waiting (wq (s::state)) th cs = waiting s th cs" + by (auto simp:s_waiting_def cs_waiting_def) + +lemma dm_depend_threads: + fixes th s + assumes vt: "vt step s" + and in_dom: "(Th th) \ Domain (depend s)" + shows "th \ threads s" +proof - + from in_dom obtain n where "(Th th, n) \ depend s" by auto + moreover from depend_target_th[OF this] obtain cs where "n = Cs cs" by auto + ultimately have "(Th th, Cs cs) \ depend s" by simp + hence "th \ set (wq s cs)" + by (unfold s_depend_def, auto simp:cs_waiting_def) + from wq_threads [OF vt this] show ?thesis . +qed + +lemma cp_eq_cpreced: "cp s th = cpreced s (wq s) th" +proof(unfold cp_def wq_def, induct s) + case (Cons e s') + show ?case + by (auto simp:Let_def) +next + case Nil + show ?case by (auto simp:Let_def) +qed + +fun the_th :: "node \ thread" + where "the_th (Th th) = th" + +lemma runing_unique: + fixes th1 th2 s + assumes vt: "vt step s" + and runing_1: "th1 \ runing s" + and runing_2: "th2 \ runing s" + shows "th1 = th2" +proof - + from runing_1 and runing_2 have "cp s th1 = cp s th2" + by (unfold runing_def, simp) + hence eq_max: "Max ((\th. preced th s) ` ({th1} \ dependents (wq s) th1)) = + Max ((\th. preced th s) ` ({th2} \ dependents (wq s) th2))" + (is "Max (?f ` ?A) = Max (?f ` ?B)") + by (unfold cp_eq_cpreced cpreced_def) + obtain th1' where th1_in: "th1' \ ?A" and eq_f_th1: "?f th1' = Max (?f ` ?A)" + proof - + have h1: "finite (?f ` ?A)" + proof - + have "finite ?A" + proof - + have "finite (dependents (wq s) th1)" + proof- + have "finite {th'. (Th th', Th th1) \ (depend (wq s))\<^sup>+}" + proof - + let ?F = "\ (x, y). the_th x" + have "{th'. (Th th', Th th1) \ (depend (wq s))\<^sup>+} \ ?F ` ((depend (wq s))\<^sup>+)" + apply (auto simp:image_def) + by (rule_tac x = "(Th x, Th th1)" in bexI, auto) + moreover have "finite \" + proof - + from finite_depend[OF vt] have "finite (depend s)" . + hence "finite ((depend (wq s))\<^sup>+)" + apply (unfold finite_trancl) + by (auto simp: s_depend_def cs_depend_def wq_def) + thus ?thesis by auto + qed + ultimately show ?thesis by (auto intro:finite_subset) + qed + thus ?thesis by (simp add:cs_dependents_def) + qed + thus ?thesis by simp + qed + thus ?thesis by auto + qed + moreover have h2: "(?f ` ?A) \ {}" + proof - + have "?A \ {}" by simp + thus ?thesis by simp + qed + from Max_in [OF h1 h2] + have "Max (?f ` ?A) \ (?f ` ?A)" . + thus ?thesis by (auto intro:that) + qed + obtain th2' where th2_in: "th2' \ ?B" and eq_f_th2: "?f th2' = Max (?f ` ?B)" + proof - + have h1: "finite (?f ` ?B)" + proof - + have "finite ?B" + proof - + have "finite (dependents (wq s) th2)" + proof- + have "finite {th'. (Th th', Th th2) \ (depend (wq s))\<^sup>+}" + proof - + let ?F = "\ (x, y). the_th x" + have "{th'. (Th th', Th th2) \ (depend (wq s))\<^sup>+} \ ?F ` ((depend (wq s))\<^sup>+)" + apply (auto simp:image_def) + by (rule_tac x = "(Th x, Th th2)" in bexI, auto) + moreover have "finite \" + proof - + from finite_depend[OF vt] have "finite (depend s)" . + hence "finite ((depend (wq s))\<^sup>+)" + apply (unfold finite_trancl) + by (auto simp: s_depend_def cs_depend_def wq_def) + thus ?thesis by auto + qed + ultimately show ?thesis by (auto intro:finite_subset) + qed + thus ?thesis by (simp add:cs_dependents_def) + qed + thus ?thesis by simp + qed + thus ?thesis by auto + qed + moreover have h2: "(?f ` ?B) \ {}" + proof - + have "?B \ {}" by simp + thus ?thesis by simp + qed + from Max_in [OF h1 h2] + have "Max (?f ` ?B) \ (?f ` ?B)" . + thus ?thesis by (auto intro:that) + qed + from eq_f_th1 eq_f_th2 eq_max + have eq_preced: "preced th1' s = preced th2' s" by auto + hence eq_th12: "th1' = th2'" + proof (rule preced_unique) + from th1_in have "th1' = th1 \ (th1' \ dependents (wq s) th1)" by simp + thus "th1' \ threads s" + proof + assume "th1' \ dependents (wq s) th1" + hence "(Th th1') \ Domain ((depend s)^+)" + apply (unfold cs_dependents_def cs_depend_def s_depend_def) + by (auto simp:Domain_def) + hence "(Th th1') \ Domain (depend s)" by (simp add:trancl_domain) + from dm_depend_threads[OF vt this] show ?thesis . + next + assume "th1' = th1" + with runing_1 show ?thesis + by (unfold runing_def readys_def, auto) + qed + next + from th2_in have "th2' = th2 \ (th2' \ dependents (wq s) th2)" by simp + thus "th2' \ threads s" + proof + assume "th2' \ dependents (wq s) th2" + hence "(Th th2') \ Domain ((depend s)^+)" + apply (unfold cs_dependents_def cs_depend_def s_depend_def) + by (auto simp:Domain_def) + hence "(Th th2') \ Domain (depend s)" by (simp add:trancl_domain) + from dm_depend_threads[OF vt this] show ?thesis . + next + assume "th2' = th2" + with runing_2 show ?thesis + by (unfold runing_def readys_def, auto) + qed + qed + from th1_in have "th1' = th1 \ th1' \ dependents (wq s) th1" by simp + thus ?thesis + proof + assume eq_th': "th1' = th1" + from th2_in have "th2' = th2 \ th2' \ dependents (wq s) th2" by simp + thus ?thesis + proof + assume "th2' = th2" thus ?thesis using eq_th' eq_th12 by simp + next + assume "th2' \ dependents (wq s) th2" + with eq_th12 eq_th' have "th1 \ dependents (wq s) th2" by simp + hence "(Th th1, Th th2) \ (depend s)^+" + by (unfold cs_dependents_def s_depend_def cs_depend_def, simp) + hence "Th th1 \ Domain ((depend s)^+)" using Domain_def [of "(depend s)^+"] + by auto + hence "Th th1 \ Domain (depend s)" by (simp add:trancl_domain) + then obtain n where d: "(Th th1, n) \ depend s" by (auto simp:Domain_def) + from depend_target_th [OF this] + obtain cs' where "n = Cs cs'" by auto + with d have "(Th th1, Cs cs') \ depend s" by simp + with runing_1 have "False" + apply (unfold runing_def readys_def s_depend_def) + by (auto simp:eq_waiting) + thus ?thesis by simp + qed + next + assume th1'_in: "th1' \ dependents (wq s) th1" + from th2_in have "th2' = th2 \ th2' \ dependents (wq s) th2" by simp + thus ?thesis + proof + assume "th2' = th2" + with th1'_in eq_th12 have "th2 \ dependents (wq s) th1" by simp + hence "(Th th2, Th th1) \ (depend s)^+" + by (unfold cs_dependents_def s_depend_def cs_depend_def, simp) + hence "Th th2 \ Domain ((depend s)^+)" using Domain_def [of "(depend s)^+"] + by auto + hence "Th th2 \ Domain (depend s)" by (simp add:trancl_domain) + then obtain n where d: "(Th th2, n) \ depend s" by (auto simp:Domain_def) + from depend_target_th [OF this] + obtain cs' where "n = Cs cs'" by auto + with d have "(Th th2, Cs cs') \ depend s" by simp + with runing_2 have "False" + apply (unfold runing_def readys_def s_depend_def) + by (auto simp:eq_waiting) + thus ?thesis by simp + next + assume "th2' \ dependents (wq s) th2" + with eq_th12 have "th1' \ dependents (wq s) th2" by simp + hence h1: "(Th th1', Th th2) \ (depend s)^+" + by (unfold cs_dependents_def s_depend_def cs_depend_def, simp) + from th1'_in have h2: "(Th th1', Th th1) \ (depend s)^+" + by (unfold cs_dependents_def s_depend_def cs_depend_def, simp) + show ?thesis + proof(rule dchain_unique[OF vt h1 _ h2, symmetric]) + from runing_1 show "th1 \ readys s" by (simp add:runing_def) + from runing_2 show "th2 \ readys s" by (simp add:runing_def) + qed + qed + qed +qed + +lemma create_pre: + assumes stp: "step s e" + and not_in: "th \ threads s" + and is_in: "th \ threads (e#s)" + obtains prio where "e = Create th prio" +proof - + from assms + show ?thesis + proof(cases) + case (thread_create prio max_prio thread) + with is_in not_in have "e = Create th prio" by simp + from that[OF this] show ?thesis . + next + case (thread_exit thread) + with assms show ?thesis by (auto intro!:that) + next + case (thread_P thread) + with assms show ?thesis by (auto intro!:that) + next + case (thread_V thread) + with assms show ?thesis by (auto intro!:that) + next + case (thread_set thread) + with assms show ?thesis by (auto intro!:that) + qed +qed + +lemma length_down_to_in: + assumes le_ij: "i \ j" + and le_js: "j \ length s" + shows "length (down_to j i s) = j - i" +proof - + have "length (down_to j i s) = length (from_to i j (rev s))" + by (unfold down_to_def, auto) + also have "\ = j - i" + proof(rule length_from_to_in[OF le_ij]) + from le_js show "j \ length (rev s)" by simp + qed + finally show ?thesis . +qed + + +lemma moment_head: + assumes le_it: "Suc i \ length t" + obtains e where "moment (Suc i) t = e#moment i t" +proof - + have "i \ Suc i" by simp + from length_down_to_in [OF this le_it] + have "length (down_to (Suc i) i t) = 1" by auto + then obtain e where "down_to (Suc i) i t = [e]" + apply (cases "(down_to (Suc i) i t)") by auto + moreover have "down_to (Suc i) 0 t = down_to (Suc i) i t @ down_to i 0 t" + by (rule down_to_conc[symmetric], auto) + ultimately have eq_me: "moment (Suc i) t = e#(moment i t)" + by (auto simp:down_to_moment) + from that [OF this] show ?thesis . +qed + +lemma cnp_cnv_eq: + fixes th s + assumes "vt step s" + and "th \ threads s" + shows "cntP s th = cntV s th" +proof - + from assms show ?thesis + proof(induct) + case (vt_cons s e) + have ih: "th \ threads s \ cntP s th = cntV s th" by fact + have not_in: "th \ threads (e # s)" by fact + have "step s e" by fact + thus ?case proof(cases) + case (thread_create prio max_prio thread) + assume eq_e: "e = Create thread prio" + hence "thread \ threads (e#s)" by simp + with not_in and eq_e have "th \ threads s" by auto + from ih [OF this] show ?thesis using eq_e + by (auto simp:cntP_def cntV_def count_def) + next + case (thread_exit thread) + assume eq_e: "e = Exit thread" + and not_holding: "holdents s thread = {}" + have vt_s: "vt step s" by fact + from finite_holding[OF vt_s] have "finite (holdents s thread)" . + with not_holding have "cntCS s thread = 0" by (unfold cntCS_def, auto) + moreover have "thread \ readys s" using thread_exit by (auto simp:runing_def) + moreover note cnp_cnv_cncs[OF vt_s, of thread] + ultimately have eq_thread: "cntP s thread = cntV s thread" by auto + show ?thesis + proof(cases "th = thread") + case True + with eq_thread eq_e show ?thesis + by (auto simp:cntP_def cntV_def count_def) + next + case False + with not_in and eq_e have "th \ threads s" by simp + from ih[OF this] and eq_e show ?thesis + by (auto simp:cntP_def cntV_def count_def) + qed + next + case (thread_P thread cs) + assume eq_e: "e = P thread cs" + have "thread \ runing s" by fact + with not_in eq_e have neq_th: "thread \ th" + by (auto simp:runing_def readys_def) + from not_in eq_e have "th \ threads s" by simp + from ih[OF this] and neq_th and eq_e show ?thesis + by (auto simp:cntP_def cntV_def count_def) + next + case (thread_V thread cs) + assume eq_e: "e = V thread cs" + have "thread \ runing s" by fact + with not_in eq_e have neq_th: "thread \ th" + by (auto simp:runing_def readys_def) + from not_in eq_e have "th \ threads s" by simp + from ih[OF this] and neq_th and eq_e show ?thesis + by (auto simp:cntP_def cntV_def count_def) + next + case (thread_set thread prio) + assume eq_e: "e = Set thread prio" + and "thread \ runing s" + hence "thread \ threads (e#s)" + by (simp add:runing_def readys_def) + with not_in and eq_e have "th \ threads s" by auto + from ih [OF this] show ?thesis using eq_e + by (auto simp:cntP_def cntV_def count_def) + qed + next + case vt_nil + show ?case by (auto simp:cntP_def cntV_def count_def) + qed +qed + +lemma eq_depend: + "depend (wq s) = depend s" +by (unfold cs_depend_def s_depend_def, auto) + +lemma count_eq_dependents: + assumes vt: "vt step s" + and eq_pv: "cntP s th = cntV s th" + shows "dependents (wq s) th = {}" +proof - + from cnp_cnv_cncs[OF vt] and eq_pv + have "cntCS s th = 0" + by (auto split:if_splits) + moreover have "finite {cs. (Cs cs, Th th) \ depend s}" + proof - + from finite_holding[OF vt, of th] show ?thesis + by (simp add:holdents_def) + qed + ultimately have h: "{cs. (Cs cs, Th th) \ depend s} = {}" + by (unfold cntCS_def holdents_def cs_dependents_def, auto) + show ?thesis + proof(unfold cs_dependents_def) + { assume "{th'. (Th th', Th th) \ (depend (wq s))\<^sup>+} \ {}" + then obtain th' where "(Th th', Th th) \ (depend (wq s))\<^sup>+" by auto + hence "False" + proof(cases) + assume "(Th th', Th th) \ depend (wq s)" + thus "False" by (auto simp:cs_depend_def) + next + fix c + assume "(c, Th th) \ depend (wq s)" + with h and eq_depend show "False" + by (cases c, auto simp:cs_depend_def) + qed + } thus "{th'. (Th th', Th th) \ (depend (wq s))\<^sup>+} = {}" by auto + qed +qed + +lemma dependents_threads: + fixes s th + assumes vt: "vt step s" + shows "dependents (wq s) th \ threads s" +proof + { fix th th' + assume h: "th \ {th'a. (Th th'a, Th th') \ (depend (wq s))\<^sup>+}" + have "Th th \ Domain (depend s)" + proof - + from h obtain th' where "(Th th, Th th') \ (depend (wq s))\<^sup>+" by auto + hence "(Th th) \ Domain ( (depend (wq s))\<^sup>+)" by (auto simp:Domain_def) + with trancl_domain have "(Th th) \ Domain (depend (wq s))" by simp + thus ?thesis using eq_depend by simp + qed + from dm_depend_threads[OF vt this] + have "th \ threads s" . + } note hh = this + fix th1 + assume "th1 \ dependents (wq s) th" + hence "th1 \ {th'a. (Th th'a, Th th) \ (depend (wq s))\<^sup>+}" + by (unfold cs_dependents_def, simp) + from hh [OF this] show "th1 \ threads s" . +qed + +lemma finite_threads: + assumes vt: "vt step s" + shows "finite (threads s)" +proof - + from vt show ?thesis + proof(induct) + case (vt_cons s e) + assume vt: "vt step s" + and step: "step s e" + and ih: "finite (threads s)" + from step + show ?case + proof(cases) + case (thread_create prio max_prio thread) + assume eq_e: "e = Create thread prio" + with ih + show ?thesis by (unfold eq_e, auto) + next + case (thread_exit thread) + assume eq_e: "e = Exit thread" + with ih show ?thesis + by (unfold eq_e, auto) + next + case (thread_P thread cs) + assume eq_e: "e = P thread cs" + with ih show ?thesis by (unfold eq_e, auto) + next + case (thread_V thread cs) + assume eq_e: "e = V thread cs" + with ih show ?thesis by (unfold eq_e, auto) + next + case (thread_set thread prio) + from vt_cons thread_set show ?thesis by simp + qed + next + case vt_nil + show ?case by (auto) + qed +qed + +lemma Max_f_mono: + assumes seq: "A \ B" + and np: "A \ {}" + and fnt: "finite B" + shows "Max (f ` A) \ Max (f ` B)" +proof(rule Max_mono) + from seq show "f ` A \ f ` B" by auto +next + from np show "f ` A \ {}" by auto +next + from fnt and seq show "finite (f ` B)" by auto +qed + +lemma cp_le: + assumes vt: "vt step s" + and th_in: "th \ threads s" + shows "cp s th \ Max ((\ th. (preced th s)) ` threads s)" +proof(unfold cp_eq_cpreced cpreced_def cs_dependents_def) + show "Max ((\th. preced th s) ` ({th} \ {th'. (Th th', Th th) \ (depend (wq s))\<^sup>+})) + \ Max ((\th. preced th s) ` threads s)" + (is "Max (?f ` ?A) \ Max (?f ` ?B)") + proof(rule Max_f_mono) + show "{th} \ {th'. (Th th', Th th) \ (depend (wq s))\<^sup>+} \ {}" by simp + next + from finite_threads [OF vt] + show "finite (threads s)" . + next + from th_in + show "{th} \ {th'. (Th th', Th th) \ (depend (wq s))\<^sup>+} \ threads s" + apply (auto simp:Domain_def) + apply (rule_tac dm_depend_threads[OF vt]) + apply (unfold trancl_domain [of "depend s", symmetric]) + by (unfold cs_depend_def s_depend_def, auto simp:Domain_def) + qed +qed + +lemma le_cp: + assumes vt: "vt step s" + shows "preced th s \ cp s th" +proof(unfold cp_eq_cpreced preced_def cpreced_def, simp) + show "Prc (original_priority th s) (birthtime th s) + \ Max (insert (Prc (original_priority th s) (birthtime th s)) + ((\th. Prc (original_priority th s) (birthtime th s)) ` dependents (wq s) th))" + (is "?l \ Max (insert ?l ?A)") + proof(cases "?A = {}") + case False + have "finite ?A" (is "finite (?f ` ?B)") + proof - + have "finite ?B" + proof- + have "finite {th'. (Th th', Th th) \ (depend (wq s))\<^sup>+}" + proof - + let ?F = "\ (x, y). the_th x" + have "{th'. (Th th', Th th) \ (depend (wq s))\<^sup>+} \ ?F ` ((depend (wq s))\<^sup>+)" + apply (auto simp:image_def) + by (rule_tac x = "(Th x, Th th)" in bexI, auto) + moreover have "finite \" + proof - + from finite_depend[OF vt] have "finite (depend s)" . + hence "finite ((depend (wq s))\<^sup>+)" + apply (unfold finite_trancl) + by (auto simp: s_depend_def cs_depend_def wq_def) + thus ?thesis by auto + qed + ultimately show ?thesis by (auto intro:finite_subset) + qed + thus ?thesis by (simp add:cs_dependents_def) + qed + thus ?thesis by simp + qed + from Max_insert [OF this False, of ?l] show ?thesis by auto + next + case True + thus ?thesis by auto + qed +qed + +lemma max_cp_eq: + assumes vt: "vt step s" + shows "Max ((cp s) ` threads s) = Max ((\ th. (preced th s)) ` threads s)" + (is "?l = ?r") +proof(cases "threads s = {}") + case True + thus ?thesis by auto +next + case False + have "?l \ ((cp s) ` threads s)" + proof(rule Max_in) + from finite_threads[OF vt] + show "finite (cp s ` threads s)" by auto + next + from False show "cp s ` threads s \ {}" by auto + qed + then obtain th + where th_in: "th \ threads s" and eq_l: "?l = cp s th" by auto + have "\ \ ?r" by (rule cp_le[OF vt th_in]) + moreover have "?r \ cp s th" (is "Max (?f ` ?A) \ cp s th") + proof - + have "?r \ (?f ` ?A)" + proof(rule Max_in) + from finite_threads[OF vt] + show " finite ((\th. preced th s) ` threads s)" by auto + next + from False show " (\th. preced th s) ` threads s \ {}" by auto + qed + then obtain th' where + th_in': "th' \ ?A " and eq_r: "?r = ?f th'" by auto + from le_cp [OF vt, of th'] eq_r + have "?r \ cp s th'" by auto + moreover have "\ \ cp s th" + proof(fold eq_l) + show " cp s th' \ Max (cp s ` threads s)" + proof(rule Max_ge) + from th_in' show "cp s th' \ cp s ` threads s" + by auto + next + from finite_threads[OF vt] + show "finite (cp s ` threads s)" by auto + qed + qed + ultimately show ?thesis by auto + qed + ultimately show ?thesis using eq_l by auto +qed + +lemma max_cp_readys_threads_pre: + assumes vt: "vt step s" + and np: "threads s \ {}" + shows "Max (cp s ` readys s) = Max (cp s ` threads s)" +proof(unfold max_cp_eq[OF vt]) + show "Max (cp s ` readys s) = Max ((\th. preced th s) ` threads s)" + proof - + let ?p = "Max ((\th. preced th s) ` threads s)" + let ?f = "(\th. preced th s)" + have "?p \ ((\th. preced th s) ` threads s)" + proof(rule Max_in) + from finite_threads[OF vt] show "finite (?f ` threads s)" by simp + next + from np show "?f ` threads s \ {}" by simp + qed + then obtain tm where tm_max: "?f tm = ?p" and tm_in: "tm \ threads s" + by (auto simp:Image_def) + from th_chain_to_ready [OF vt tm_in] + have "tm \ readys s \ (\th'. th' \ readys s \ (Th tm, Th th') \ (depend s)\<^sup>+)" . + thus ?thesis + proof + assume "\th'. th' \ readys s \ (Th tm, Th th') \ (depend s)\<^sup>+ " + then obtain th' where th'_in: "th' \ readys s" + and tm_chain:"(Th tm, Th th') \ (depend s)\<^sup>+" by auto + have "cp s th' = ?f tm" + proof(subst cp_eq_cpreced, subst cpreced_def, rule Max_eqI) + from dependents_threads[OF vt] finite_threads[OF vt] + show "finite ((\th. preced th s) ` ({th'} \ dependents (wq s) th'))" + by (auto intro:finite_subset) + next + fix p assume p_in: "p \ (\th. preced th s) ` ({th'} \ dependents (wq s) th')" + from tm_max have " preced tm s = Max ((\th. preced th s) ` threads s)" . + moreover have "p \ \" + proof(rule Max_ge) + from finite_threads[OF vt] + show "finite ((\th. preced th s) ` threads s)" by simp + next + from p_in and th'_in and dependents_threads[OF vt, of th'] + show "p \ (\th. preced th s) ` threads s" + by (auto simp:readys_def) + qed + ultimately show "p \ preced tm s" by auto + next + show "preced tm s \ (\th. preced th s) ` ({th'} \ dependents (wq s) th')" + proof - + from tm_chain + have "tm \ dependents (wq s) th'" + by (unfold cs_dependents_def s_depend_def cs_depend_def, auto) + thus ?thesis by auto + qed + qed + with tm_max + have h: "cp s th' = Max ((\th. preced th s) ` threads s)" by simp + show ?thesis + proof (fold h, rule Max_eqI) + fix q + assume "q \ cp s ` readys s" + then obtain th1 where th1_in: "th1 \ readys s" + and eq_q: "q = cp s th1" by auto + show "q \ cp s th'" + apply (unfold h eq_q) + apply (unfold cp_eq_cpreced cpreced_def) + apply (rule Max_mono) + proof - + from dependents_threads [OF vt, of th1] th1_in + show "(\th. preced th s) ` ({th1} \ dependents (wq s) th1) \ + (\th. preced th s) ` threads s" + by (auto simp:readys_def) + next + show "(\th. preced th s) ` ({th1} \ dependents (wq s) th1) \ {}" by simp + next + from finite_threads[OF vt] + show " finite ((\th. preced th s) ` threads s)" by simp + qed + next + from finite_threads[OF vt] + show "finite (cp s ` readys s)" by (auto simp:readys_def) + next + from th'_in + show "cp s th' \ cp s ` readys s" by simp + qed + next + assume tm_ready: "tm \ readys s" + show ?thesis + proof(fold tm_max) + have cp_eq_p: "cp s tm = preced tm s" + proof(unfold cp_eq_cpreced cpreced_def, rule Max_eqI) + fix y + assume hy: "y \ (\th. preced th s) ` ({tm} \ dependents (wq s) tm)" + show "y \ preced tm s" + proof - + { fix y' + assume hy' : "y' \ ((\th. preced th s) ` dependents (wq s) tm)" + have "y' \ preced tm s" + proof(unfold tm_max, rule Max_ge) + from hy' dependents_threads[OF vt, of tm] + show "y' \ (\th. preced th s) ` threads s" by auto + next + from finite_threads[OF vt] + show "finite ((\th. preced th s) ` threads s)" by simp + qed + } with hy show ?thesis by auto + qed + next + from dependents_threads[OF vt, of tm] finite_threads[OF vt] + show "finite ((\th. preced th s) ` ({tm} \ dependents (wq s) tm))" + by (auto intro:finite_subset) + next + show "preced tm s \ (\th. preced th s) ` ({tm} \ dependents (wq s) tm)" + by simp + qed + moreover have "Max (cp s ` readys s) = cp s tm" + proof(rule Max_eqI) + from tm_ready show "cp s tm \ cp s ` readys s" by simp + next + from finite_threads[OF vt] + show "finite (cp s ` readys s)" by (auto simp:readys_def) + next + fix y assume "y \ cp s ` readys s" + then obtain th1 where th1_readys: "th1 \ readys s" + and h: "y = cp s th1" by auto + show "y \ cp s tm" + apply(unfold cp_eq_p h) + apply(unfold cp_eq_cpreced cpreced_def tm_max, rule Max_mono) + proof - + from finite_threads[OF vt] + show "finite ((\th. preced th s) ` threads s)" by simp + next + show "(\th. preced th s) ` ({th1} \ dependents (wq s) th1) \ {}" + by simp + next + from dependents_threads[OF vt, of th1] th1_readys + show "(\th. preced th s) ` ({th1} \ dependents (wq s) th1) + \ (\th. preced th s) ` threads s" + by (auto simp:readys_def) + qed + qed + ultimately show " Max (cp s ` readys s) = preced tm s" by simp + qed + qed + qed +qed + +lemma max_cp_readys_threads: + assumes vt: "vt step s" + shows "Max (cp s ` readys s) = Max (cp s ` threads s)" +proof(cases "threads s = {}") + case True + thus ?thesis + by (auto simp:readys_def) +next + case False + show ?thesis by (rule max_cp_readys_threads_pre[OF vt False]) +qed + +lemma readys_threads: + shows "readys s \ threads s" +proof + fix th + assume "th \ readys s" + thus "th \ threads s" + by (unfold readys_def, auto) +qed + +lemma eq_holding: "holding (wq s) th cs = holding s th cs" + apply (unfold s_holding_def cs_holding_def, simp) + done + +lemma f_image_eq: + assumes h: "\ a. a \ A \ f a = g a" + shows "f ` A = g ` A" +proof + show "f ` A \ g ` A" + by(rule image_subsetI, auto intro:h) +next + show "g ` A \ f ` A" + by(rule image_subsetI, auto intro:h[symmetric]) +qed + +end \ No newline at end of file