(* Title: HOL/MicroJava/BV/LBVComplete.thy
ID: $Id$
Author: Gerwin Klein
Copyright 2000 Technische Universitaet Muenchen
*)
header {* Completeness of the LBV *}
(* This theory is currently broken. The port to exceptions
didn't make it into the Isabelle 2001 release. It is included for
documentation only. See Isabelle 99-2 for a working copy of this
theory. *)
theory LBVComplete = BVSpec + LBVSpec + EffectMono:
constdefs
contains_targets :: "[instr list, certificate, method_type, p_count] => bool"
"contains_targets ins cert phi pc ==
\<forall>pc' \<in> set (succs (ins!pc) pc).
pc' \<noteq> pc+1 \<and> pc' < length ins --> cert!pc' = phi!pc'"
fits :: "[instr list, certificate, method_type] => bool"
"fits ins cert phi == \<forall>pc. pc < length ins -->
contains_targets ins cert phi pc \<and>
(cert!pc = None \<or> cert!pc = phi!pc)"
is_target :: "[instr list, p_count] => bool"
"is_target ins pc ==
\<exists>pc'. pc \<noteq> pc'+1 \<and> pc' < length ins \<and> pc \<in> set (succs (ins!pc') pc')"
constdefs
make_cert :: "[instr list, method_type] => certificate"
"make_cert ins phi ==
map (\<lambda>pc. if is_target ins pc then phi!pc else None) [0..length ins(]"
make_Cert :: "[jvm_prog, prog_type] => prog_certificate"
"make_Cert G Phi == \<lambda> C sig. let (C,rT,(maxs,maxl,b)) = the (method (G,C) sig)
in make_cert b (Phi C sig)"
lemmas [simp del] = split_paired_Ex
lemma make_cert_target:
"[| pc < length ins; is_target ins pc |] ==> make_cert ins phi ! pc = phi!pc"
by (simp add: make_cert_def)
lemma make_cert_approx:
"[| pc < length ins; make_cert ins phi ! pc \<noteq> phi ! pc |] ==>
make_cert ins phi ! pc = None"
by (auto simp add: make_cert_def)
lemma make_cert_contains_targets:
"pc < length ins ==> contains_targets ins (make_cert ins phi) phi pc"
proof (unfold contains_targets_def, intro strip, elim conjE)
fix pc'
assume "pc < length ins"
"pc' \<in> set (succs (ins ! pc) pc)"
"pc' \<noteq> pc+1" and
pc': "pc' < length ins"
hence "is_target ins pc'"
by (auto simp add: is_target_def)
with pc'
show "make_cert ins phi ! pc' = phi ! pc'"
by (auto intro: make_cert_target)
qed
theorem fits_make_cert:
"fits ins (make_cert ins phi) phi"
by (auto dest: make_cert_approx simp add: fits_def make_cert_contains_targets)
lemma fitsD:
"[| fits ins cert phi; pc' \<in> set (succs (ins!pc) pc);
pc' \<noteq> Suc pc; pc < length ins; pc' < length ins |]
==> cert!pc' = phi!pc'"
by (clarsimp simp add: fits_def contains_targets_def)
lemma fitsD2:
"[| fits ins cert phi; pc < length ins; cert!pc = Some s |]
==> cert!pc = phi!pc"
by (auto simp add: fits_def)
lemma wtl_inst_mono:
"[| wtl_inst i G rT s1 cert mxs mpc pc = OK s1'; fits ins cert phi;
pc < length ins; G \<turnstile> s2 <=' s1; i = ins!pc |] ==>
\<exists> s2'. wtl_inst (ins!pc) G rT s2 cert mxs mpc pc = OK s2' \<and> (G \<turnstile> s2' <=' s1')"
proof -
assume pc: "pc < length ins" "i = ins!pc"
assume wtl: "wtl_inst i G rT s1 cert mxs mpc pc = OK s1'"
assume fits: "fits ins cert phi"
assume G: "G \<turnstile> s2 <=' s1"
let "?eff s" = "eff i G s"
from wtl G
have app: "app i G mxs rT s2" by (auto simp add: wtl_inst_OK app_mono)
from wtl G
have eff: "G \<turnstile> ?eff s2 <=' ?eff s1"
by (auto intro: eff_mono simp add: wtl_inst_OK)
{ also
fix pc'
assume "pc' \<in> set (succs i pc)" "pc' \<noteq> pc+1"
with wtl
have "G \<turnstile> ?eff s1 <=' cert!pc'"
by (auto simp add: wtl_inst_OK)
finally
have "G\<turnstile> ?eff s2 <=' cert!pc'" .
} note cert = this
have "\<exists>s2'. wtl_inst i G rT s2 cert mxs mpc pc = OK s2' \<and> G \<turnstile> s2' <=' s1'"
proof (cases "pc+1 \<in> set (succs i pc)")
case True
with wtl
have s1': "s1' = ?eff s1" by (simp add: wtl_inst_OK)
have "wtl_inst i G rT s2 cert mxs mpc pc = OK (?eff s2) \<and> G \<turnstile> ?eff s2 <=' s1'"
(is "?wtl \<and> ?G")
proof
from True s1'
show ?G by (auto intro: eff)
from True app wtl
show ?wtl
by (clarsimp intro!: cert simp add: wtl_inst_OK)
qed
thus ?thesis by blast
next
case False
with wtl
have "s1' = cert ! Suc pc" by (simp add: wtl_inst_OK)
with False app wtl
have "wtl_inst i G rT s2 cert mxs mpc pc = OK s1' \<and> G \<turnstile> s1' <=' s1'"
by (clarsimp intro!: cert simp add: wtl_inst_OK)
thus ?thesis by blast
qed
with pc show ?thesis by simp
qed
lemma wtl_cert_mono:
"[| wtl_cert i G rT s1 cert mxs mpc pc = OK s1'; fits ins cert phi;
pc < length ins; G \<turnstile> s2 <=' s1; i = ins!pc |] ==>
\<exists> s2'. wtl_cert (ins!pc) G rT s2 cert mxs mpc pc = OK s2' \<and> (G \<turnstile> s2' <=' s1')"
proof -
assume wtl: "wtl_cert i G rT s1 cert mxs mpc pc = OK s1'" and
fits: "fits ins cert phi" "pc < length ins"
"G \<turnstile> s2 <=' s1" "i = ins!pc"
show ?thesis
proof (cases (open) "cert!pc")
case None
with wtl fits
show ?thesis
by - (rule wtl_inst_mono [elim_format], (simp add: wtl_cert_def)+)
next
case Some
with wtl fits
have G: "G \<turnstile> s2 <=' (Some a)"
by - (rule sup_state_opt_trans, auto simp add: wtl_cert_def split: if_splits)
from Some wtl
have "wtl_inst i G rT (Some a) cert mxs mpc pc = OK s1'"
by (simp add: wtl_cert_def split: if_splits)
with G fits
have "\<exists> s2'. wtl_inst (ins!pc) G rT (Some a) cert mxs mpc pc = OK s2' \<and>
(G \<turnstile> s2' <=' s1')"
by - (rule wtl_inst_mono, (simp add: wtl_cert_def)+)
with Some G
show ?thesis by (simp add: wtl_cert_def)
qed
qed
lemma wt_instr_imp_wtl_inst:
"[| wt_instr (ins!pc) G rT phi mxs max_pc pc; fits ins cert phi;
pc < length ins; length ins = max_pc |] ==>
wtl_inst (ins!pc) G rT (phi!pc) cert mxs max_pc pc \<noteq> Err"
proof -
assume wt: "wt_instr (ins!pc) G rT phi mxs max_pc pc"
assume fits: "fits ins cert phi"
assume pc: "pc < length ins" "length ins = max_pc"
from wt
have app: "app (ins!pc) G mxs rT (phi!pc)" by (simp add: wt_instr_def)
from wt pc
have pc': "!!pc'. pc' \<in> set (succs (ins!pc) pc) ==> pc' < length ins"
by (simp add: wt_instr_def)
let ?s' = "eff (ins!pc) G (phi!pc)"
from wt fits pc
have cert: "!!pc'. [|pc' \<in> set (succs (ins!pc) pc); pc' < max_pc; pc' \<noteq> pc+1|]
==> G \<turnstile> ?s' <=' cert!pc'"
by (auto dest: fitsD simp add: wt_instr_def)
from app pc cert pc'
show ?thesis
by (auto simp add: wtl_inst_OK)
qed
lemma wt_less_wtl:
"[| wt_instr (ins!pc) G rT phi mxs max_pc pc;
wtl_inst (ins!pc) G rT (phi!pc) cert mxs max_pc pc = OK s;
fits ins cert phi; Suc pc < length ins; length ins = max_pc |] ==>
G \<turnstile> s <=' phi ! Suc pc"
proof -
assume wt: "wt_instr (ins!pc) G rT phi mxs max_pc pc"
assume wtl: "wtl_inst (ins!pc) G rT (phi!pc) cert mxs max_pc pc = OK s"
assume fits: "fits ins cert phi"
assume pc: "Suc pc < length ins" "length ins = max_pc"
{ assume suc: "Suc pc \<in> set (succs (ins ! pc) pc)"
with wtl have "s = eff (ins!pc) G (phi!pc)"
by (simp add: wtl_inst_OK)
also from suc wt have "G \<turnstile> ... <=' phi!Suc pc"
by (simp add: wt_instr_def)
finally have ?thesis .
}
moreover
{ assume "Suc pc \<notin> set (succs (ins ! pc) pc)"
with wtl
have "s = cert!Suc pc"
by (simp add: wtl_inst_OK)
with fits pc
have ?thesis
by - (cases "cert!Suc pc", simp, drule fitsD2, assumption+, simp)
}
ultimately
show ?thesis by blast
qed
lemma wt_instr_imp_wtl_cert:
"[| wt_instr (ins!pc) G rT phi mxs max_pc pc; fits ins cert phi;
pc < length ins; length ins = max_pc |] ==>
wtl_cert (ins!pc) G rT (phi!pc) cert mxs max_pc pc \<noteq> Err"
proof -
assume "wt_instr (ins!pc) G rT phi mxs max_pc pc" and
fits: "fits ins cert phi" and
pc: "pc < length ins" and
"length ins = max_pc"
hence wtl: "wtl_inst (ins!pc) G rT (phi!pc) cert mxs max_pc pc \<noteq> Err"
by (rule wt_instr_imp_wtl_inst)
hence "cert!pc = None ==> ?thesis"
by (simp add: wtl_cert_def)
moreover
{ fix s
assume c: "cert!pc = Some s"
with fits pc
have "cert!pc = phi!pc"
by (rule fitsD2)
from this c wtl
have ?thesis
by (clarsimp simp add: wtl_cert_def)
}
ultimately
show ?thesis by blast
qed
lemma wt_less_wtl_cert:
"[| wt_instr (ins!pc) G rT phi mxs max_pc pc;
wtl_cert (ins!pc) G rT (phi!pc) cert mxs max_pc pc = OK s;
fits ins cert phi; Suc pc < length ins; length ins = max_pc |] ==>
G \<turnstile> s <=' phi ! Suc pc"
proof -
assume wtl: "wtl_cert (ins!pc) G rT (phi!pc) cert mxs max_pc pc = OK s"
assume wti: "wt_instr (ins!pc) G rT phi mxs max_pc pc"
"fits ins cert phi"
"Suc pc < length ins" "length ins = max_pc"
{ assume "cert!pc = None"
with wtl
have "wtl_inst (ins!pc) G rT (phi!pc) cert mxs max_pc pc = OK s"
by (simp add: wtl_cert_def)
with wti
have ?thesis
by - (rule wt_less_wtl)
}
moreover
{ fix t
assume c: "cert!pc = Some t"
with wti
have "cert!pc = phi!pc"
by - (rule fitsD2, simp+)
with c wtl
have "wtl_inst (ins!pc) G rT (phi!pc) cert mxs max_pc pc = OK s"
by (simp add: wtl_cert_def)
with wti
have ?thesis
by - (rule wt_less_wtl)
}
ultimately
show ?thesis by blast
qed
text {*
\medskip
Main induction over the instruction list.
*}
theorem wt_imp_wtl_inst_list:
"\<forall> pc. (\<forall>pc'. pc' < length all_ins -->
wt_instr (all_ins ! pc') G rT phi mxs (length all_ins) pc') -->
fits all_ins cert phi -->
(\<exists>l. pc = length l \<and> all_ins = l@ins) -->
pc < length all_ins -->
(\<forall> s. (G \<turnstile> s <=' (phi!pc)) -->
wtl_inst_list ins G rT cert mxs (length all_ins) pc s \<noteq> Err)"
(is "\<forall>pc. ?wt --> ?fits --> ?l pc ins --> ?len pc --> ?wtl pc ins"
is "\<forall>pc. ?C pc ins" is "?P ins")
proof (induct "?P" "ins")
case Nil
show "?P []" by simp
next
fix i ins'
assume Cons: "?P ins'"
show "?P (i#ins')"
proof (intro allI impI, elim exE conjE)
fix pc s l
assume wt : "\<forall>pc'. pc' < length all_ins -->
wt_instr (all_ins ! pc') G rT phi mxs (length all_ins) pc'"
assume fits: "fits all_ins cert phi"
assume l : "pc < length all_ins"
assume G : "G \<turnstile> s <=' phi ! pc"
assume pc : "all_ins = l@i#ins'" "pc = length l"
hence i : "all_ins ! pc = i"
by (simp add: nth_append)
from l wt
have wti: "wt_instr (all_ins!pc) G rT phi mxs (length all_ins) pc" by blast
with fits l
have c: "wtl_cert (all_ins!pc) G rT (phi!pc) cert mxs (length all_ins) pc \<noteq> Err"
by - (drule wt_instr_imp_wtl_cert, auto)
from Cons
have "?C (Suc pc) ins'" by blast
with wt fits pc
have IH: "?len (Suc pc) --> ?wtl (Suc pc) ins'" by auto
show "wtl_inst_list (i#ins') G rT cert mxs (length all_ins) pc s \<noteq> Err"
proof (cases "?len (Suc pc)")
case False
with pc
have "ins' = []" by simp
with G i c fits l
show ?thesis by (auto dest: wtl_cert_mono)
next
case True
with IH
have wtl: "?wtl (Suc pc) ins'" by blast
from c wti fits l True
obtain s'' where
"wtl_cert (all_ins!pc) G rT (phi!pc) cert mxs (length all_ins) pc = OK s''"
"G \<turnstile> s'' <=' phi ! Suc pc"
by clarsimp (drule wt_less_wtl_cert, auto)
moreover
from calculation fits G l
obtain s' where
c': "wtl_cert (all_ins!pc) G rT s cert mxs (length all_ins) pc = OK s'" and
"G \<turnstile> s' <=' s''"
by - (drule wtl_cert_mono, auto)
ultimately
have G': "G \<turnstile> s' <=' phi ! Suc pc"
by - (rule sup_state_opt_trans)
with wtl
have "wtl_inst_list ins' G rT cert mxs (length all_ins) (Suc pc) s' \<noteq> Err"
by auto
with i c'
show ?thesis by auto
qed
qed
qed
lemma fits_imp_wtl_method_complete:
"[| wt_method G C pTs rT mxs mxl ins phi; fits ins cert phi |]
==> wtl_method G C pTs rT mxs mxl ins cert"
by (simp add: wt_method_def wtl_method_def)
(rule wt_imp_wtl_inst_list [rule_format, elim_format], auto simp add: wt_start_def)
lemma wtl_method_complete:
"wt_method G C pTs rT mxs mxl ins phi
==> wtl_method G C pTs rT mxs mxl ins (make_cert ins phi)"
proof -
assume "wt_method G C pTs rT mxs mxl ins phi"
moreover
have "fits ins (make_cert ins phi) phi"
by (rule fits_make_cert)
ultimately
show ?thesis
by (rule fits_imp_wtl_method_complete)
qed
theorem wtl_complete:
"wt_jvm_prog G Phi ==> wtl_jvm_prog G (make_Cert G Phi)"
proof -
assume wt: "wt_jvm_prog G Phi"
{ fix C S fs mdecls sig rT code
assume "(C,S,fs,mdecls) \<in> set G" "(sig,rT,code) \<in> set mdecls"
moreover
from wt obtain wf_mb where "wf_prog wf_mb G"
by (blast dest: wt_jvm_progD)
ultimately
have "method (G,C) sig = Some (C,rT,code)"
by (simp add: methd)
} note this [simp]
from wt
show ?thesis
apply (clarsimp simp add: wt_jvm_prog_def wtl_jvm_prog_def wf_prog_def wf_cdecl_def)
apply (drule bspec, assumption)
apply (clarsimp simp add: wf_mdecl_def)
apply (drule bspec, assumption)
apply (clarsimp simp add: make_Cert_def)
apply (clarsimp dest!: wtl_method_complete)
done
qed
lemmas [simp] = split_paired_Ex
end