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theory BVNoTypeError = JVMDefensive + BVSpecTypeSafe:(* Title: HOL/MicroJava/BV/BVNoTypeErrors.thy ID: $Id: BVNoTypeError.html,v 1.1 2002/11/28 16:11:18 kleing Exp $ Author: Gerwin Klein Copyright GPL *) header {* \isaheader{Welltyped Programs produce no Type Errors} *} theory BVNoTypeError = JVMDefensive + BVSpecTypeSafe: text {* Some simple lemmas about the type testing functions of the defensive JVM: *} lemma typeof_NoneD [simp,dest]: "typeof (\<lambda>v. None) v = Some x \<Longrightarrow> ¬isAddr v" by (cases v) auto lemma isRef_def2: "isRef v = (v = Null \<or> (\<exists>loc. v = Addr loc))" by (cases v) (auto simp add: isRef_def) lemma isRef [simp]: "G,hp,ihp \<turnstile> v ::\<preceq>i Init (RefT T) \<Longrightarrow> isRef v" by (cases v) (auto simp add: iconf_def conf_def isRef_def) lemma isIntg [simp]: "G,hp,ihp \<turnstile> v ::\<preceq>i Init (PrimT Integer) \<Longrightarrow> isIntg v" by (cases v) (auto simp add: iconf_def conf_def) declare approx_loc_len [simp] approx_stk_len [simp] (* fixme: move to List.thy *) lemma list_all2I: "\<forall>(x,y) \<in> set (zip a b). P x y \<Longrightarrow> length a = length b \<Longrightarrow> list_all2 P a b" by (simp add: list_all2_def) lemma app'Store[simp]: "app' (Store idx, G, C', pc, maxs, rT, (ST,LT)) = (\<exists>T ST'. ST = T#ST' \<and> idx < length LT)" by (cases ST, auto) lemma app'GetField[simp]: "app' (Getfield F C, G, C', pc, maxs, rT, (ST,LT)) = (\<exists>oT vT ST'. ST = oT#ST' \<and> is_class G C \<and> field (G,C) F = Some (C,vT) \<and> G \<turnstile> oT \<preceq>i (Init (Class C)))" by (cases ST, auto) lemma app'PutField[simp]: "app' (Putfield F C, G, C', pc, maxs, rT, (ST,LT)) = (\<exists>vT vT' oT ST'. ST = vT#oT#ST' \<and> is_class G C \<and> field (G,C) F = Some (C, vT') \<and> G \<turnstile> oT \<preceq>i Init (Class C) \<and> G \<turnstile> vT \<preceq>i Init vT')" apply rule defer apply clarsimp apply (cases ST) apply simp apply (cases "tl ST") apply auto done lemma app'Checkcast[simp]: "app' (Checkcast C, G, C', pc, maxs, rT, (ST,LT)) = (\<exists>rT ST'. ST = Init (RefT rT)#ST' \<and> is_class G C)" apply rule defer apply clarsimp apply (cases ST) apply simp apply (cases "hd ST") defer apply simp apply simp apply (case_tac ty) apply auto done lemma app'Pop[simp]: "app' (Pop, G, C', pc, maxs, rT, (ST,LT)) = (\<exists>T ST'. ST = T#ST')" by (cases ST, auto) lemma app'Dup[simp]: "app' (Dup, G, C', pc, maxs, rT, (ST,LT)) = (\<exists>T ST'. ST = T#ST' \<and> length ST < maxs)" by (cases ST, auto) lemma app'Dup_x1[simp]: "app' (Dup_x1, G, C', pc, maxs, rT, (ST,LT)) = (\<exists>T1 T2 ST'. ST = T1#T2#ST' \<and> length ST < maxs)" by (cases ST, simp, cases "tl ST", auto) lemma app'Dup_x2[simp]: "app' (Dup_x2, G, C', pc, maxs, rT, (ST,LT)) = (\<exists>T1 T2 T3 ST'. ST = T1#T2#T3#ST' \<and> length ST < maxs)" by (cases ST, simp, cases "tl ST", simp, cases "tl (tl ST)", auto) lemma app'Swap[simp]: "app' (Swap, G, C', pc, maxs, rT, (ST,LT)) = (\<exists>T1 T2 ST'. ST = T1#T2#ST')" by (cases ST, simp, cases "tl ST", auto) lemma app'IAdd[simp]: "app' (IAdd, G, C', pc, maxs, rT, (ST,LT)) = (\<exists>ST'. ST = Init (PrimT Integer)#Init (PrimT Integer)#ST')" by (cases ST, simp, cases "tl ST", auto) lemma app'Ifcmpeq[simp]: "app' (Ifcmpeq b, G, C', pc, maxs, rT, (ST,LT)) = (\<exists>T1 T2 ST'. ST = Init T1#Init T2#ST' \<and> 0 \<le> b + int pc \<and> ((\<exists>p. T1 = PrimT p \<and> T1 = T2) \<or> (\<exists>r r'. T1 = RefT r \<and> T2 = RefT r')))" apply auto apply (cases ST) apply simp apply (cases "tl ST") apply (case_tac a) apply auto apply (case_tac a) apply auto apply (case_tac aa) apply (case_tac ty) apply auto done lemma app'Return[simp]: "app' (Return, G, C', pc, maxs, rT, (ST,LT)) = (\<exists>T ST'. ST = T#ST'\<and> G \<turnstile> T \<preceq>i Init rT)" by (cases ST, auto) lemma app'Throw[simp]: "app' (Throw, G, C', pc, maxs, rT, (ST,LT)) = (\<exists>ST' r. ST = Init (RefT r)#ST')" apply (cases ST, simp) apply (cases "hd ST") apply auto done lemma app'Invoke[simp]: "app' (Invoke C mn fpTs, G, C', pc, maxs, rT, ST, LT) = (\<exists>apTs X ST' mD' rT' b' z. ST = (rev apTs) @ X # ST' \<and> mn \<noteq> init \<and> length apTs = length fpTs \<and> is_class G C \<and> (\<forall>(aT,fT)\<in>set(zip apTs fpTs). G \<turnstile> aT \<preceq>i Init fT) \<and> method (G,C) (mn,fpTs) = Some (mD', rT', b') \<and> G \<turnstile> X \<preceq>i Init (Class C))" (is "?app ST LT = ?P ST LT") proof assume "?P ST LT" thus "?app ST LT" by (auto simp add: min_def list_all2_def) next assume app: "?app ST LT" hence l: "length fpTs < length ST" by simp obtain xs ys where xs: "ST = xs @ ys" "length xs = length fpTs" proof - have "ST = take (length fpTs) ST @ drop (length fpTs) ST" by simp moreover from l have "length (take (length fpTs) ST) = length fpTs" by (simp add: min_def) ultimately show ?thesis .. qed obtain apTs where "ST = (rev apTs) @ ys" and "length apTs = length fpTs" proof - have "ST = rev (rev xs) @ ys" by simp with xs show ?thesis by - (rule that, assumption, simp) qed moreover from l xs obtain X ST' where "ys = X#ST'" by (auto simp add: neq_Nil_conv) ultimately have "ST = (rev apTs) @ X # ST'" "length apTs = length fpTs" by auto with app show "?P ST LT" apply (clarsimp simp add: list_all2_def min_def) apply ((rule exI)+, (rule conjI)?)+ apply auto done qed lemma app'Invoke_special[simp]: "app' (Invoke_special C mn fpTs, G, C', pc, maxs, rT, (ST,LT)) = (\<exists>apTs X ST' rT' b' z. ST = (rev apTs) @ X # ST' \<and> mn = init \<and> length apTs = length fpTs \<and> is_class G C \<and> (\<forall>(aT,fT)\<in>set(zip apTs fpTs). G \<turnstile> aT \<preceq>i (Init fT)) \<and> method (G,C) (mn,fpTs) = Some (C, rT', b') \<and> ((\<exists>pc. X = UnInit C pc) \<or> (X = PartInit C' \<and> G \<turnstile> C' \<prec>C1 C)))" (is "?app ST LT = ?P ST LT") proof assume "?P ST LT" thus "?app ST LT" by (auto simp add: min_def list_all2_def nth_append) next assume app: "?app ST LT" hence l: "length fpTs < length ST" by simp obtain xs ys where xs: "ST = xs @ ys" "length xs = length fpTs" proof - have "ST = take (length fpTs) ST @ drop (length fpTs) ST" by simp moreover from l have "length (take (length fpTs) ST) = length fpTs" by (simp add: min_def) ultimately show ?thesis .. qed obtain apTs where "ST = (rev apTs) @ ys" and "length apTs = length fpTs" proof - have "ST = rev (rev xs) @ ys" by simp with xs show ?thesis by - (rule that, assumption, simp) qed moreover from l xs obtain X ST' where "ys = X#ST'" by (auto simp add: neq_Nil_conv) ultimately have "ST = (rev apTs) @ X # ST'" "length apTs = length fpTs" by auto with app show "?P ST LT" apply (clarsimp simp add: list_all2_def min_def nth_append) apply ((rule exI)+, (rule conjI)?)+ apply auto done qed lemma app'ArrLoad[simp]: "app' (ArrLoad, G, C', pc, maxs, rT, (ST,LT)) = (\<exists>T ST'. ST=Init (PrimT Integer)#Init (T.[])#ST')" apply (case_tac ST) apply simp apply (case_tac list) apply simp apply (case_tac aa) apply (case_tac ty) apply simp apply (case_tac ref_ty) apply auto done lemma app'ArrStore[simp]: "app' (ArrStore, G, C', pc, maxs, rT, (ST,LT)) = (\<exists>T T' ST'. ST=Init T#Init (PrimT Integer)#Init (T'.[])#ST')" apply (case_tac ST, simp) apply (case_tac list) apply (case_tac a, simp, simp, simp) apply (case_tac lista, simp) apply (case_tac a, simp, simp, simp) apply simp apply (case_tac a) defer apply simp apply simp apply simp apply (case_tac ab) apply (case_tac tya) apply simp apply (case_tac ref_ty) apply auto done lemma app'ArrLength[simp]: "app' (ArrLength, G, C', pc, maxs, rT, (ST,LT)) = (\<exists>T ST'. ST = Init (T.[])#ST')" apply (case_tac ST, simp) apply (case_tac a) apply (case_tac ty, simp) apply (case_tac ref_ty) apply auto done lemma app'ArrNew[simp]: "app' (ArrNew T, G, C', pc, maxs, rT, (ST,LT)) = (\<exists>ST'. ST = Init (PrimT Integer)#ST' \<and> is_type G T \<and> noRA T \<and> dim T + 1 \<le> max_dim)" apply (cases ST) apply auto done declare conf_ArrayD [dest!] text {* The main theorem: welltyped programs do not produce type errors if they are started in a conformant state. *} theorem no_type_error: assumes welltyped: "wt_jvm_prog G Phi" and conforms: "G,Phi \<turnstile>JVM s \<surd>" shows "exec_d G (Normal s) \<noteq> TypeError" proof - from welltyped obtain mb where wf: "wf_prog mb G" by (fast dest: wt_jvm_progD) obtain xcp hp ihp frs where s [simp]: "s = (xcp, hp, ihp, frs)" by (cases s) from conforms have "xcp \<noteq> None \<or> frs = [] \<Longrightarrow> check G s" by (unfold correct_state_def check_def) auto moreover { assume "¬(xcp \<noteq> None \<or> frs = [])" then obtain stk loc C sig pc r frs' where xcp [simp]: "xcp = None" and frs [simp]: "frs = (stk,loc,C,sig,pc,r)#frs'" by (clarsimp simp add: neq_Nil_conv) fast from conforms obtain ST LT z rT maxs maxl ins et where hconf: "G \<turnstile>h hp \<surd>" and class: "is_class G C" and meth: "method (G, C) sig = Some (C, rT, maxs, maxl, ins, et)" and phi: "((ST,LT), z) \<in> Phi C sig ! pc" and frame: "correct_frame G hp ihp (ST,LT) maxl ins (stk,loc,C,sig,pc,r)" and frames: "correct_frames G hp ihp Phi rT sig z r frs'" by simp (rule correct_stateE) from frame obtain stk: "approx_stk G hp ihp stk ST" and loc: "approx_loc G hp ihp loc LT" and init: "fst sig = init \<longrightarrow> corresponds stk loc (ST, LT) ihp (fst r) (PartInit C) \<and> (\<exists>l. fst r = Addr l \<and> hp l \<noteq> None \<and> (ihp l = PartInit C \<or> (\<exists>C'. ihp l = Init (Class C'))))" and pc: "pc < length ins" and len: "length loc = length (snd sig) + maxl + 1" by (rule correct_frameE) note approx_val_def [simp] from welltyped meth conforms have "wt_instr (ins!pc) G C rT (Phi C sig) maxs (fst sig=init) (length ins) et pc" by simp (rule wt_jvm_prog_impl_wt_instr_cor) then obtain app': "app (ins!pc) G C pc maxs (length ins) rT (fst sig=init) et (Phi C sig!pc) " and eff: "\<forall>(pc', s')\<in>set (eff (ins ! pc) G pc et (Phi C sig ! pc)). pc' < length ins" by (simp add: wt_instr_def phi) blast from eff have pc': "\<forall>pc' \<in> set (succs (ins!pc) pc (Phi C sig!pc)). pc' < length ins" by (simp add: eff_def) blast from app' phi have app: "xcpt_app (ins!pc) G pc et \<and> app' (ins!pc, G, C, pc, maxs, rT, (ST,LT)) \<and> (fst sig = init \<and> ins ! pc = Return \<longrightarrow> z) \<and> ((\<exists>C m p. ins ! pc = Invoke_special C m p \<and> ST!length p = PartInit C) \<longrightarrow> ¬ z)" apply (clarsimp simp add: app_def) apply (drule bspec, assumption) apply clarsimp done with eff stk loc pc' have "check_instr (ins!pc) G hp ihp stk loc C sig pc r frs'" proof (cases "ins!pc") case (Getfield F C) with app stk loc phi obtain v vT stk' where class: "is_class G C" and field: "field (G, C) F = Some (C, vT)" and stk: "stk = v # stk'" and conf: "G,hp,ihp \<turnstile> v ::\<preceq>i Init (Class C)" apply clarsimp apply (blast dest: iconf_widen [OF _ _ wf]) done from conf have isRef: "isRef v" by simp moreover { assume "v \<noteq> Null" moreover from conf have "G,hp \<turnstile> v ::\<preceq> Class C" and "is_init hp ihp v" by auto moreover note field isRef wf ultimately have "\<exists>D vs. hp (the_Addr v) = Some (Obj D vs) \<and> is_init hp ihp v \<and> G \<turnstile> D \<preceq>C C" by (auto dest!: non_np_objD) } ultimately show ?thesis using Getfield field class stk hconf apply clarsimp apply (fastsimp dest!: hconfD widen_cfs_fields [OF _ _ wf] oconf_objD) done next case (Putfield F C) with app stk loc phi obtain v ref vT stk' where class: "is_class G C" and field: "field (G, C) F = Some (C, vT)" and stk: "stk = v # ref # stk'" and confv: "G,hp,ihp \<turnstile> v ::\<preceq>i Init vT" and confr: "G,hp,ihp \<turnstile> ref ::\<preceq>i Init (Class C)" apply clarsimp apply (blast dest: iconf_widen [OF _ _ wf]) done from confr have isRef: "isRef ref" by simp moreover from confv have "is_init hp ihp v" by (simp add: iconf_def) moreover { assume "ref \<noteq> Null" moreover from confr have "G,hp \<turnstile> ref ::\<preceq> Class C" and "is_init hp ihp ref" by auto moreover note field isRef wf ultimately have "\<exists>D vs. hp (the_Addr ref) = Some (Obj D vs) \<and> is_init hp ihp ref \<and> G \<turnstile> D \<preceq>C C" by (auto dest: non_np_objD) } ultimately show ?thesis using Putfield field class stk confv by (clarsimp simp add: iconf_def) next case (Invoke C mn ps) with stk app phi show ?thesis apply (clarsimp simp del: app'.simps) apply (drule app'Invoke [THEN iffD1]) apply (clarsimp dest!: approx_stk_append_lemma simp add: nth_append) apply (drule iconf_widen [OF _ _ wf], assumption) apply (clarsimp simp add: iconf_def) apply (drule non_npD, assumption) apply clarsimp apply (drule conf_ClassD) apply clarsimp apply (drule widen_methd [OF _ wf], assumption) apply (clarsimp simp add: approx_stk_rev [symmetric]) apply (drule list_all2I, assumption) apply (unfold approx_stk_def approx_loc_def) apply (simp add: list_all2_approx) apply (drule list_all2_iconf_widen [OF wf], assumption+) done next case (Invoke_special C mn ps) with stk app phi show ?thesis apply (clarsimp simp del: app'.simps) apply (drule app'Invoke_special [THEN iffD1]) apply (clarsimp dest!: approx_stk_append_lemma simp add: nth_append) apply (erule disjE) apply (clarsimp simp add: iconf_def isRef_def) apply (clarsimp simp add: approx_stk_rev [symmetric]) apply (drule list_all2I, assumption) apply (simp add: list_all2_approx approx_stk_def approx_loc_def) apply (drule list_all2_iconf_widen [OF wf], assumption+) apply (clarsimp simp add: iconf_def isRef_def) apply (clarsimp simp add: approx_stk_rev [symmetric]) apply (drule list_all2I, assumption) apply (unfold approx_stk_def approx_loc_def) apply (simp add: list_all2_approx) apply (drule list_all2_iconf_widen [OF wf], assumption+) done next case Return with stk app init phi meth frames show ?thesis apply clarsimp apply (drule iconf_widen [OF _ _ wf], assumption) apply (clarsimp simp add: iconf_def neq_Nil_conv constructor_ok_def is_init_def isRef_def2) done next case (Ret idx) from welltyped meth conforms s frs have finite: "finite (Phi C sig!pc)" by simp (rule phi_finite) with Ret app obtain R where idx: "idx < length LT" and R: "LT!idx = OK (Init (RA R))" by clarsimp moreover from R idx loc have "loc!idx = RetAddr R" apply (simp add: approx_loc_def) apply (clarsimp simp add: list_all2_conv_all_nth) apply (erule allE, erule impE, assumption) apply (clarsimp simp add: iconf_def conf_def) apply (cases "loc!idx") apply auto done moreover from finite Ret pc' R have "R < length ins" apply (auto simp add: set_SOME_lists finite_imageI theRA_def) apply (drule bspec, assumption) apply simp done ultimately show ?thesis using Ret loc by simp qed auto hence "check G s" by (simp add: check_def meth) } ultimately have "check G s" by blast thus "exec_d G (Normal s) \<noteq> TypeError" .. qed text {* The theorem above tells us that, in welltyped programs, the defensive machine reaches the same result as the aggressive one (after arbitrarily many steps). *} theorem welltyped_aggressive_imp_defensive: "wt_jvm_prog G Phi \<Longrightarrow> G,Phi \<turnstile>JVM s \<surd> \<Longrightarrow> G \<turnstile> s -jvm\<rightarrow> t \<Longrightarrow> G \<turnstile> (Normal s) -jvmd\<rightarrow> (Normal t)" apply (unfold exec_all_def) apply (erule rtrancl_induct) apply (simp add: exec_all_d_def) apply simp apply (fold exec_all_def) apply (frule BV_correct, assumption+) apply (drule no_type_error, assumption, drule no_type_error_commutes, simp) apply (simp add: exec_all_d_def) apply (rule rtrancl_trans, assumption) apply blast done text {* As corollary we get that the aggressive and the defensive machine are equivalent for welltyped programs (if started in a conformant state or in the canonical start state) *} corollary welltyped_commutes: fixes G ("\<Gamma>") and Phi ("\<Phi>") assumes "wt_jvm_prog \<Gamma> \<Phi>" and "\<Gamma>,\<Phi> \<turnstile>JVM s \<surd>" shows "\<Gamma> \<turnstile> (Normal s) -jvmd\<rightarrow> (Normal t) = \<Gamma> \<turnstile> s -jvm\<rightarrow> t" by rule (erule defensive_imp_aggressive,rule welltyped_aggressive_imp_defensive) corollary welltyped_initial_commutes: fixes G ("\<Gamma>") and Phi ("\<Phi>") assumes "wt_jvm_prog \<Gamma> \<Phi>" assumes "is_class \<Gamma> C" "method (\<Gamma>,C) (m,[]) = Some (C, b)" "m \<noteq> init" defines start: "s \<equiv> start_state \<Gamma> C m" shows "\<Gamma> \<turnstile> (Normal s) -jvmd\<rightarrow> (Normal t) = \<Gamma> \<turnstile> s -jvm\<rightarrow> t" proof - have "\<Gamma>,\<Phi> \<turnstile>JVM s \<surd>" by (unfold start, rule BV_correct_initial) thus ?thesis by - (rule welltyped_commutes) qed end
lemma typeof_NoneD:
typeof (%v. None) v = Some x ==> ¬ isAddr v
lemma isRef_def2:
isRef v = (v = Null | (EX loc. v = Addr loc))
lemma isRef:
G,hp,ihp \<turnstile> v ::\<preceq>i Init (RefT T) ==> isRef v
lemma isIntg:
G,hp,ihp \<turnstile> v ::\<preceq>i Init (PrimT Integer) ==> isIntg v
lemma list_all2I:
[| Ball (set (zip a b)) (split P); length a = length b |] ==> list_all2 P a b
lemma app'Store:
app' (Store idx, G, C', pc, maxs, rT, ST, LT) = (EX T ST'. ST = T # ST' & idx < length LT)
lemma app'GetField:
app' (Getfield F C, G, C', pc, maxs, rT, ST, LT) = (EX oT vT ST'. ST = oT # ST' & is_class G C & field (G, C) F = Some (C, vT) & G |- oT <=i Init (Class C))
lemma app'PutField:
app' (Putfield F C, G, C', pc, maxs, rT, ST, LT) = (EX vT vT' oT ST'. ST = vT # oT # ST' & is_class G C & field (G, C) F = Some (C, vT') & G |- oT <=i Init (Class C) & G |- vT <=i Init vT')
lemma app'Checkcast:
app' (Checkcast C, G, C', pc, maxs, rT, ST, LT) = (EX rT ST'. ST = Init (RefT rT) # ST' & is_class G C)
lemma app'Pop:
app' (Pop, G, C', pc, maxs, rT, ST, LT) = (EX T ST'. ST = T # ST')
lemma app'Dup:
app' (Dup, G, C', pc, maxs, rT, ST, LT) = (EX T ST'. ST = T # ST' & length ST < maxs)
lemma app'Dup_x1:
app' (Dup_x1, G, C', pc, maxs, rT, ST, LT) = (EX T1 T2 ST'. ST = T1 # T2 # ST' & length ST < maxs)
lemma app'Dup_x2:
app' (Dup_x2, G, C', pc, maxs, rT, ST, LT) = (EX T1 T2 T3 ST'. ST = T1 # T2 # T3 # ST' & length ST < maxs)
lemma app'Swap:
app' (Swap, G, C', pc, maxs, rT, ST, LT) = (EX T1 T2 ST'. ST = T1 # T2 # ST')
lemma app'IAdd:
app' (IAdd, G, C', pc, maxs, rT, ST, LT) = (EX ST'. ST = Init (PrimT Integer) # Init (PrimT Integer) # ST')
lemma app'Ifcmpeq:
app' (Ifcmpeq b, G, C', pc, maxs, rT, ST, LT) = (EX T1 T2 ST'. ST = Init T1 # Init T2 # ST' & 0 <= b + int pc & ((EX p. T1 = PrimT p & T1 = T2) | (EX r r'. T1 = RefT r & T2 = RefT r')))
lemma app'Return:
app' (Return, G, C', pc, maxs, rT, ST, LT) = (EX T ST'. ST = T # ST' & G |- T <=i Init rT)
lemma app'Throw:
app' (Throw, G, C', pc, maxs, rT, ST, LT) = (EX ST' r. ST = Init (RefT r) # ST')
lemma app'Invoke:
app' (Invoke C mn fpTs, G, C', pc, maxs, rT, ST, LT) = (EX apTs X ST' mD' rT' b' z. ST = rev apTs @ X # ST' & mn ~= init & length apTs = length fpTs & is_class G C & (ALL (aT, fT):set (zip apTs fpTs). G |- aT <=i Init fT) & method (G, C) (mn, fpTs) = Some (mD', rT', b') & G |- X <=i Init (Class C))
lemma app'Invoke_special:
app' (Invoke_special C mn fpTs, G, C', pc, maxs, rT, ST, LT) = (EX apTs X ST' rT' b' z. ST = rev apTs @ X # ST' & mn = init & length apTs = length fpTs & is_class G C & (ALL (aT, fT):set (zip apTs fpTs). G |- aT <=i Init fT) & method (G, C) (mn, fpTs) = Some (C, rT', b') & ((EX pc. X = UnInit C pc) | X = PartInit C' & G |- C' <=C1 C))
lemma app'ArrLoad:
app' (ArrLoad, G, C', pc, maxs, rT, ST, LT) = (EX T ST'. ST = Init (PrimT Integer) # Init (T.[]) # ST')
lemma app'ArrStore:
app' (ArrStore, G, C', pc, maxs, rT, ST, LT) = (EX T T' ST'. ST = Init T # Init (PrimT Integer) # Init (T'.[]) # ST')
lemma app'ArrLength:
app' (ArrLength, G, C', pc, maxs, rT, ST, LT) = (EX T ST'. ST = Init (T.[]) # ST')
lemma app'ArrNew:
app' (ArrNew T, G, C', pc, maxs, rT, ST, LT) = (EX ST'. ST = Init (PrimT Integer) # ST' & is_type G T & noRA T & dim T + 1 <= max_dim)
theorem
[| wt_jvm_prog G Phi; G,Phi |-JVM s [ok] |] ==> exec_d G (Normal s) ~= TypeError
theorem welltyped_aggressive_imp_defensive:
[| wt_jvm_prog G Phi; G,Phi |-JVM s [ok]; G |- s -jvm-> t |] ==> G |- Normal s -jvmd-> Normal t
corollary
[| wt_jvm_prog G Phi; G,Phi |-JVM s [ok] |] ==> G |- Normal s -jvmd-> Normal t = G |- s -jvm-> t
corollary
[| wt_jvm_prog G Phi; is_class G C; method (G, C) (m, []) = Some (C, b); m ~= init |] ==> G |- Normal (start_state G C m) -jvmd-> Normal t = G |- start_state G C m -jvm-> t