Added unary and binary operations like (+,-,<, ...); Added smallstep semantics (no proofs about it yet).
1 (* Title: HOL/Bali/Eval.thy
3 Author: David von Oheimb
4 License: GPL (GNU GENERAL PUBLIC LICENSE)
6 header {* Operational evaluation (big-step) semantics of Java expressions and
10 theory Eval = State + DeclConcepts:
14 improvements over Java Specification 1.0:
16 \item dynamic method lookup does not need to consider the return type
18 \item throw raises a NullPointer exception if a null reference is given, and
19 each throw of a standard exception yield a fresh exception object
21 \item if there is not enough memory even to allocate an OutOfMemory exception,
22 evaluation/execution fails, i.e. simply stops (was not specified)
23 \item array assignment checks lhs (and may throw exceptions) before evaluating
25 \item fixed exact positions of class initializations
26 (immediate at first active use)
31 \item evaluation vs. (single-step) transition semantics
32 evaluation semantics chosen, because:
34 \item[++] less verbose and therefore easier to read (and to handle in proofs)
35 \item[+] more abstract
36 \item[+] intermediate values (appearing in recursive rules) need not be
37 stored explicitly, e.g. no call body construct or stack of invocation
38 frames containing local variables and return addresses for method calls
40 \item[+] convenient rule induction for subject reduction theorem
41 \item[-] no interleaving (for parallelism) can be described
42 \item[-] stating a property of infinite executions requires the meta-level
43 argument that this property holds for any finite prefixes of it
44 (e.g. stopped using a counter that is decremented to zero and then
45 throwing an exception)
47 \item unified evaluation for variables, expressions, expression lists,
49 \item the value entry in statement rules is redundant
50 \item the value entry in rules is irrelevant in case of exceptions, but its full
51 inclusion helps to make the rule structure independent of exception occurence.
52 \item as irrelevant value entries are ignored, it does not matter if they are
54 For simplicity, (fixed) arbitrary values are preferred over "free" values.
55 \item the rule format is such that the start state may contain an exception.
57 \item[++] faciliates exception handling
60 \item the rules are defined carefully in order to be applicable even in not
61 type-correct situations (yielding undefined values),
62 e.g. @{text "the_Addr (Val (Bool b)) = arbitrary"}.
65 \item[-] less readable because of auxiliary functions like @{text the_Addr}
67 Alternative: "defensive" evaluation throwing some InternalError exception
68 in case of (impossible, for correct programs) type mismatches
69 \item there is exactly one rule per syntactic construct
71 \item[+] no redundancy in case distinctions
73 \item halloc fails iff there is no free heap address. When there is
74 only one free heap address left, it returns an OutOfMemory exception.
75 In this way it is guaranteed that when an OutOfMemory exception is thrown for
76 the first time, there is a free location on the heap to allocate it.
77 \item the allocation of objects that represent standard exceptions is deferred
78 until execution of any enclosing catch clause, which is transparent to
81 \item[-] requires an auxiliary execution relation
82 \item[++] avoids copies of allocation code and awkward case distinctions
83 (whether there is enough memory to allocate the exception) in
86 \item unfortunately @{text new_Addr} is not directly executable because of
91 \item local variables are initialized with default values
92 (no definite assignment)
93 \item garbage collection not considered, therefore also no finalizers
94 \item stack overflow and memory overflow during class initialization not
96 \item exceptions in initializations not replaced by ExceptionInInitializerError
100 types vvar = "val \<times> (val \<Rightarrow> state \<Rightarrow> state)"
101 vals = "(val, vvar, val list) sum3"
103 "vvar" <= (type) "val \<times> (val \<Rightarrow> state \<Rightarrow> state)"
104 "vals" <= (type)"(val, vvar, val list) sum3"
107 dummy_res :: "vals" ("\<diamondsuit>")
109 "\<diamondsuit>" == "In1 Unit"
112 arbitrary3 :: "('al + 'ar, 'b, 'c) sum3 \<Rightarrow> vals"
113 "arbitrary3 \<equiv> sum3_case (In1 \<circ> sum_case (\<lambda>x. arbitrary) (\<lambda>x. Unit))
114 (\<lambda>x. In2 arbitrary) (\<lambda>x. In3 arbitrary)"
116 lemma [simp]: "arbitrary3 (In1l x) = In1 arbitrary"
117 by (simp add: arbitrary3_def)
119 lemma [simp]: "arbitrary3 (In1r x) = \<diamondsuit>"
120 by (simp add: arbitrary3_def)
122 lemma [simp]: "arbitrary3 (In2 x) = In2 arbitrary"
123 by (simp add: arbitrary3_def)
125 lemma [simp]: "arbitrary3 (In3 x) = In3 arbitrary"
126 by (simp add: arbitrary3_def)
129 section "exception throwing and catching"
132 throw :: "val \<Rightarrow> abopt \<Rightarrow> abopt"
133 "throw a' x \<equiv> abrupt_if True (Some (Xcpt (Loc (the_Addr a')))) (np a' x)"
136 "throw a' x = abrupt_if True (Some (Xcpt (Loc (the_Addr a')))) (np a' x)"
137 apply (unfold throw_def)
138 apply (simp (no_asm))
142 fits :: "prog \<Rightarrow> st \<Rightarrow> val \<Rightarrow> ty \<Rightarrow> bool" ("_,_\<turnstile>_ fits _"[61,61,61,61]60)
143 "G,s\<turnstile>a' fits T \<equiv> (\<exists>rt. T=RefT rt) \<longrightarrow> a'=Null \<or> G\<turnstile>obj_ty(lookup_obj s a')\<preceq>T"
145 lemma fits_Null [simp]: "G,s\<turnstile>Null fits T"
146 by (simp add: fits_def)
149 lemma fits_Addr_RefT [simp]:
150 "G,s\<turnstile>Addr a fits RefT t = G\<turnstile>obj_ty (the (heap s a))\<preceq>RefT t"
151 by (simp add: fits_def)
153 lemma fitsD: "\<And>X. G,s\<turnstile>a' fits T \<Longrightarrow> (\<exists>pt. T = PrimT pt) \<or>
154 (\<exists>t. T = RefT t) \<and> a' = Null \<or>
155 (\<exists>t. T = RefT t) \<and> a' \<noteq> Null \<and> G\<turnstile>obj_ty (lookup_obj s a')\<preceq>T"
156 apply (unfold fits_def)
157 apply (case_tac "\<exists>pt. T = PrimT pt")
161 apply (case_tac "a' = Null")
166 catch ::"prog \<Rightarrow> state \<Rightarrow> qtname \<Rightarrow> bool" ("_,_\<turnstile>catch _"[61,61,61]60)
167 "G,s\<turnstile>catch C\<equiv>\<exists>xc. abrupt s=Some (Xcpt xc) \<and>
168 G,store s\<turnstile>Addr (the_Loc xc) fits Class C"
170 lemma catch_Norm [simp]: "\<not>G,Norm s\<turnstile>catch tn"
171 apply (unfold catch_def)
172 apply (simp (no_asm))
175 lemma catch_XcptLoc [simp]:
176 "G,(Some (Xcpt (Loc a)),s)\<turnstile>catch C = G,s\<turnstile>Addr a fits Class C"
177 apply (unfold catch_def)
178 apply (simp (no_asm))
182 new_xcpt_var :: "vname \<Rightarrow> state \<Rightarrow> state"
183 "new_xcpt_var vn \<equiv>
184 \<lambda>(x,s). Norm (lupd(VName vn\<mapsto>Addr (the_Loc (the_Xcpt (the x)))) s)"
186 lemma new_xcpt_var_def2 [simp]:
187 "new_xcpt_var vn (x,s) =
188 Norm (lupd(VName vn\<mapsto>Addr (the_Loc (the_Xcpt (the x)))) s)"
189 apply (unfold new_xcpt_var_def)
190 apply (simp (no_asm))
199 assign :: "('a \<Rightarrow> state \<Rightarrow> state) \<Rightarrow> 'a \<Rightarrow> state \<Rightarrow> state"
200 "assign f v \<equiv> \<lambda>(x,s). let (x',s') = (if x = None then f v else id) (x,s)
201 in (x',if x' = None then s' else s)"
204 lemma assign_Norm_Norm [simp]:
205 "f v \<lparr>abrupt=None,store=s\<rparr> = \<lparr>abrupt=None,store=s'\<rparr>
206 \<Longrightarrow> assign f v \<lparr>abrupt=None,store=s\<rparr> = \<lparr>abrupt=None,store=s'\<rparr>"
207 by (simp add: assign_def Let_def)
210 lemma assign_Norm_Norm [simp]:
211 "f v (Norm s) = Norm s' \<Longrightarrow> assign f v (Norm s) = Norm s'"
212 by (simp add: assign_def Let_def)
215 lemma assign_Norm_Some [simp]:
216 "\<lbrakk>abrupt (f v \<lparr>abrupt=None,store=s\<rparr>) = Some y\<rbrakk>
217 \<Longrightarrow> assign f v \<lparr>abrupt=None,store=s\<rparr> = \<lparr>abrupt=Some y,store =s\<rparr>"
218 by (simp add: assign_def Let_def split_beta)
221 lemma assign_Norm_Some [simp]:
222 "\<lbrakk>abrupt (f v (Norm s)) = Some y\<rbrakk>
223 \<Longrightarrow> assign f v (Norm s) = (Some y,s)"
224 by (simp add: assign_def Let_def split_beta)
227 lemma assign_Some [simp]:
228 "assign f v (Some x,s) = (Some x,s)"
229 by (simp add: assign_def Let_def split_beta)
231 lemma assign_supd [simp]:
232 "assign (\<lambda>v. supd (f v)) v (x,s)
233 = (x, if x = None then f v s else s)"
237 lemma assign_raise_if [simp]:
238 "assign (\<lambda>v (x,s). ((raise_if (b s v) xcpt) x, f v s)) v (x, s) =
239 (raise_if (b s v) xcpt x, if x=None \<and> \<not>b s v then f v s else s)"
240 apply (case_tac "x = None")
245 lemma assign_raise_if [simp]:
246 "assign (\<lambda>v s. \<lparr>abrupt=(raise_if (b (store s) v) xcpt) (abrupt s),
247 store = f v (store s)\<rparr>) v s =
248 \<lparr>abrupt=raise_if (b (store s) v) xcpt (abrupt s),
249 store= if (abrupt s)=None \<and> \<not>b (store s) v
250 then f v (store s) else (store s)\<rparr>"
251 apply (case_tac "abrupt s = None")
258 init_comp_ty :: "ty \<Rightarrow> stmt"
259 "init_comp_ty T \<equiv> if (\<exists>C. T = Class C) then Init (the_Class T) else Skip"
261 lemma init_comp_ty_PrimT [simp]: "init_comp_ty (PrimT pt) = Skip"
262 apply (unfold init_comp_ty_def)
263 apply (simp (no_asm))
269 target :: "inv_mode \<Rightarrow> st \<Rightarrow> val \<Rightarrow> ref_ty \<Rightarrow> qtname"
271 \<equiv> if m = IntVir
272 then obj_class (lookup_obj s a')
273 else the_Class (RefT t)"
276 invocation_class :: "inv_mode \<Rightarrow> st \<Rightarrow> val \<Rightarrow> ref_ty \<Rightarrow> qtname"
277 "invocation_class m s a' statT
279 Static \<Rightarrow> if (\<exists> statC. statT = ClassT statC)
280 then the_Class (RefT statT)
282 | SuperM \<Rightarrow> the_Class (RefT statT)
283 | IntVir \<Rightarrow> obj_class (lookup_obj s a'))"
285 invocation_declclass::"prog \<Rightarrow> inv_mode \<Rightarrow> st \<Rightarrow> val \<Rightarrow> ref_ty \<Rightarrow> sig \<Rightarrow> qtname"
286 "invocation_declclass G m s a' statT sig
287 \<equiv> declclass (the (dynlookup G statT
288 (invocation_class m s a' statT)
291 lemma invocation_class_IntVir [simp]:
292 "invocation_class IntVir s a' statT = obj_class (lookup_obj s a')"
293 by (simp add: invocation_class_def)
295 lemma dynclass_SuperM [simp]:
296 "invocation_class SuperM s a' statT = the_Class (RefT statT)"
297 by (simp add: invocation_class_def)
299 lemma invocation_class_notIntVir [simp]:
300 "m \<noteq> IntVir \<Longrightarrow> invocation_class m s a' statT = the_Class (RefT statT)"
301 by (simp add: invocation_class_def)
304 lemma invocation_class_Static [simp]:
305 "invocation_class Static s a' statT = (if (\<exists> statC. statT = ClassT statC)
306 then the_Class (RefT statT)
308 by (simp add: invocation_class_def)
311 init_lvars :: "prog \<Rightarrow> qtname \<Rightarrow> sig \<Rightarrow> inv_mode \<Rightarrow> val \<Rightarrow> val list \<Rightarrow>
312 state \<Rightarrow> state"
313 "init_lvars G C sig mode a' pvs
314 \<equiv> \<lambda> (x,s).
315 let m = mthd (the (methd G C sig));
319 \<Rightarrow> (case e of
320 VNam v \<Rightarrow> (init_vals (table_of (lcls (mbody m)))
321 ((pars m)[\<mapsto>]pvs)) v
322 | Res \<Rightarrow> Some (default_val (resTy m)))
324 \<Rightarrow> (if mode=Static then None else Some a'))
325 in set_lvars l (if mode = Static then x else np a' x,s)"
329 lemma init_lvars_def2: "init_lvars G C sig mode a' pvs (x,s) =
334 \<Rightarrow> (case e of
336 \<Rightarrow> (init_vals
337 (table_of (lcls (mbody (mthd (the (methd G C sig))))))
338 ((pars (mthd (the (methd G C sig))))[\<mapsto>]pvs)) v
339 | Res \<Rightarrow> Some (default_val (resTy (mthd (the (methd G C sig))))))
341 \<Rightarrow> (if mode=Static then None else Some a')))
342 (if mode = Static then x else np a' x,s)"
343 apply (unfold init_lvars_def)
344 apply (simp (no_asm) add: Let_def)
348 body :: "prog \<Rightarrow> qtname \<Rightarrow> sig \<Rightarrow> expr"
349 "body G C sig \<equiv> let m = the (methd G C sig)
350 in Body (declclass m) (stmt (mbody (mthd m)))"
353 "body G C sig = Body (declclass (the (methd G C sig)))
354 (stmt (mbody (mthd (the (methd G C sig)))))"
355 apply (unfold body_def Let_def)
363 lvar :: "lname \<Rightarrow> st \<Rightarrow> vvar"
364 "lvar vn s \<equiv> (the (locals s vn), \<lambda>v. supd (lupd(vn\<mapsto>v)))"
366 fvar :: "qtname \<Rightarrow> bool \<Rightarrow> vname \<Rightarrow> val \<Rightarrow> state \<Rightarrow> vvar \<times> state"
368 \<equiv> let (oref,xf) = if stat then (Stat C,id)
369 else (Heap (the_Addr a'),np a');
371 f = (\<lambda>v. supd (upd_gobj oref n v))
372 in ((the (values (the (globs (store s) oref)) n),f),abupd xf s)"
375 \<equiv> let (oref,xf) = if stat then (Stat C,id)
376 else (Heap (the_Addr a'),np a');
378 f = (\<lambda>v. supd (upd_gobj oref n v))
379 in ((the (values (the (globs (store s) oref)) n),f),abupd xf s)"
381 avar :: "prog \<Rightarrow> val \<Rightarrow> val \<Rightarrow> state \<Rightarrow> vvar \<times> state"
383 \<equiv> let oref = Heap (the_Addr a');
386 (T,k,cs) = the_Arr (globs (store s) oref);
387 f = (\<lambda>v (x,s). (raise_if (\<not>G,s\<turnstile>v fits T)
389 ,upd_gobj oref n v s))
391 ,abupd (raise_if (\<not>i in_bounds k) IndOutBound \<circ> np a') s)"
393 lemma fvar_def2: "fvar C stat fn a' s =
396 (the (globs (store s) (if stat then Stat C else Heap (the_Addr a'))))
398 ,(\<lambda>v. supd (upd_gobj (if stat then Stat C else Heap (the_Addr a'))
401 ,abupd (if stat then id else np a') s)
403 apply (unfold fvar_def)
404 apply (simp (no_asm) add: Let_def split_beta)
407 lemma avar_def2: "avar G i' a' s =
408 ((the ((snd(snd(the_Arr (globs (store s) (Heap (the_Addr a'))))))
410 ,(\<lambda>v (x,s'). (raise_if (\<not>G,s'\<turnstile>v fits (fst(the_Arr (globs (store s)
411 (Heap (the_Addr a'))))))
413 ,upd_gobj (Heap (the_Addr a'))
414 (Inr (the_Intg i')) v s')))
415 ,abupd (raise_if (\<not>(the_Intg i') in_bounds (fst(snd(the_Arr (globs (store s)
416 (Heap (the_Addr a'))))))) IndOutBound \<circ> np a')
418 apply (unfold avar_def)
419 apply (simp (no_asm) add: Let_def split_beta)
424 "prog \<Rightarrow> qtname \<Rightarrow> qtname \<Rightarrow> vname \<Rightarrow> bool \<Rightarrow> val \<Rightarrow> state \<Rightarrow> state"
425 "check_field_access G accC statDeclC fn stat a' s
426 \<equiv> let oref = if stat then Stat statDeclC
427 else Heap (the_Addr a');
429 Heap a \<Rightarrow> obj_class (the (globs (store s) oref))
430 | Stat C \<Rightarrow> C;
431 f = (the (table_of (DeclConcepts.fields G dynC) (fn,statDeclC)))
433 (error_if (\<not> G\<turnstile>Field fn (statDeclC,f) in dynC dyn_accessible_from accC)
438 check_method_access::
439 "prog \<Rightarrow> qtname \<Rightarrow> ref_ty \<Rightarrow> inv_mode \<Rightarrow> sig \<Rightarrow> val \<Rightarrow> state \<Rightarrow> state"
440 "check_method_access G accC statT mode sig a' s
441 \<equiv> let invC = invocation_class mode (store s) a' statT;
442 dynM = the (dynlookup G statT invC sig)
444 (error_if (\<not> G\<turnstile>Methd sig dynM in invC dyn_accessible_from accC)
448 section "evaluation judgments"
450 consts eval_unop :: "unop \<Rightarrow> val \<Rightarrow> val"
452 "eval_unop UPlus v = Intg (the_Intg v)"
453 "eval_unop UMinus v = Intg (- (the_Intg v))"
454 "eval_unop UBitNot v = Intg 42" -- "FIXME: Not yet implemented"
455 "eval_unop UNot v = Bool (\<not> the_Bool v)"
457 consts eval_binop :: "binop \<Rightarrow> val \<Rightarrow> val \<Rightarrow> val"
461 "eval_binop Mul v1 v2 = Intg ((the_Intg v1) * (the_Intg v2))"
462 "eval_binop Div v1 v2 = Intg ((the_Intg v1) div (the_Intg v2))"
463 "eval_binop Mod v1 v2 = Intg ((the_Intg v1) mod (the_Intg v2))"
464 "eval_binop Plus v1 v2 = Intg ((the_Intg v1) + (the_Intg v2))"
465 "eval_binop Minus v1 v2 = Intg ((the_Intg v1) - (the_Intg v2))"
467 -- "Be aware of the explicit coercion of the shift distance to nat"
468 "eval_binop LShift v1 v2 = Intg ((the_Intg v1) * (2^(nat (the_Intg v2))))"
469 "eval_binop RShift v1 v2 = Intg ((the_Intg v1) div (2^(nat (the_Intg v2))))"
470 "eval_binop RShiftU v1 v2 = Intg 42" --"FIXME: Not yet implemented"
472 "eval_binop Less v1 v2 = Bool ((the_Intg v1) < (the_Intg v2))"
473 "eval_binop Le v1 v2 = Bool ((the_Intg v1) \<le> (the_Intg v2))"
474 "eval_binop Greater v1 v2 = Bool ((the_Intg v2) < (the_Intg v1))"
475 "eval_binop Ge v1 v2 = Bool ((the_Intg v2) \<le> (the_Intg v1))"
477 "eval_binop Eq v1 v2 = Bool (v1=v2)"
478 "eval_binop Neq v1 v2 = Bool (v1\<noteq>v2)"
479 "eval_binop BitAnd v1 v2 = Intg 42" -- "FIXME: Not yet implemented"
480 "eval_binop And v1 v2 = Bool ((the_Bool v1) \<and> (the_Bool v2))"
481 "eval_binop BitXor v1 v2 = Intg 42" -- "FIXME: Not yet implemented"
482 "eval_binop Xor v1 v2 = Bool ((the_Bool v1) \<noteq> (the_Bool v2))"
483 "eval_binop BitOr v1 v2 = Intg 42" -- "FIXME: Not yet implemented"
484 "eval_binop Or v1 v2 = Bool ((the_Bool v1) \<or> (the_Bool v2))"
488 eval :: "prog \<Rightarrow> (state \<times> term \<times> vals \<times> state) set"
489 halloc:: "prog \<Rightarrow> (state \<times> obj_tag \<times> loc \<times> state) set"
490 sxalloc:: "prog \<Rightarrow> (state \<times> state) set"
494 eval ::"[prog,state,term,vals*state]=>bool"("_|-_ -_>-> _" [61,61,80, 61]60)
495 exec ::"[prog,state,stmt ,state]=>bool"("_|-_ -_-> _" [61,61,65, 61]60)
496 evar ::"[prog,state,var ,vvar,state]=>bool"("_|-_ -_=>_-> _"[61,61,90,61,61]60)
497 eval_::"[prog,state,expr ,val, state]=>bool"("_|-_ -_->_-> _"[61,61,80,61,61]60)
498 evals::"[prog,state,expr list ,
499 val list ,state]=>bool"("_|-_ -_#>_-> _"[61,61,61,61,61]60)
500 hallo::"[prog,state,obj_tag,
501 loc,state]=>bool"("_|-_ -halloc _>_-> _"[61,61,61,61,61]60)
502 sallo::"[prog,state ,state]=>bool"("_|-_ -sxalloc-> _"[61,61, 61]60)
505 eval ::"[prog,state,term,vals\<times>state]\<Rightarrow>bool" ("_\<turnstile>_ \<midarrow>_\<succ>\<rightarrow> _" [61,61,80, 61]60)
506 exec ::"[prog,state,stmt ,state]\<Rightarrow>bool"("_\<turnstile>_ \<midarrow>_\<rightarrow> _" [61,61,65, 61]60)
507 evar ::"[prog,state,var ,vvar,state]\<Rightarrow>bool"("_\<turnstile>_ \<midarrow>_=\<succ>_\<rightarrow> _"[61,61,90,61,61]60)
508 eval_::"[prog,state,expr ,val ,state]\<Rightarrow>bool"("_\<turnstile>_ \<midarrow>_-\<succ>_\<rightarrow> _"[61,61,80,61,61]60)
509 evals::"[prog,state,expr list ,
510 val list ,state]\<Rightarrow>bool"("_\<turnstile>_ \<midarrow>_\<doteq>\<succ>_\<rightarrow> _"[61,61,61,61,61]60)
511 hallo::"[prog,state,obj_tag,
512 loc,state]\<Rightarrow>bool"("_\<turnstile>_ \<midarrow>halloc _\<succ>_\<rightarrow> _"[61,61,61,61,61]60)
513 sallo::"[prog,state, state]\<Rightarrow>bool"("_\<turnstile>_ \<midarrow>sxalloc\<rightarrow> _"[61,61, 61]60)
516 "G\<turnstile>s \<midarrow>t \<succ>\<rightarrow> w___s' " == "(s,t,w___s') \<in> eval G"
517 "G\<turnstile>s \<midarrow>t \<succ>\<rightarrow> (w, s')" <= "(s,t,w, s') \<in> eval G"
518 "G\<turnstile>s \<midarrow>t \<succ>\<rightarrow> (w,x,s')" <= "(s,t,w,x,s') \<in> eval G"
519 "G\<turnstile>s \<midarrow>c \<rightarrow> (x,s')" <= "G\<turnstile>s \<midarrow>In1r c\<succ>\<rightarrow> (\<diamondsuit>,x,s')"
520 "G\<turnstile>s \<midarrow>c \<rightarrow> s' " == "G\<turnstile>s \<midarrow>In1r c\<succ>\<rightarrow> (\<diamondsuit> , s')"
521 "G\<turnstile>s \<midarrow>e-\<succ>v \<rightarrow> (x,s')" <= "G\<turnstile>s \<midarrow>In1l e\<succ>\<rightarrow> (In1 v ,x,s')"
522 "G\<turnstile>s \<midarrow>e-\<succ>v \<rightarrow> s' " == "G\<turnstile>s \<midarrow>In1l e\<succ>\<rightarrow> (In1 v , s')"
523 "G\<turnstile>s \<midarrow>e=\<succ>vf\<rightarrow> (x,s')" <= "G\<turnstile>s \<midarrow>In2 e\<succ>\<rightarrow> (In2 vf,x,s')"
524 "G\<turnstile>s \<midarrow>e=\<succ>vf\<rightarrow> s' " == "G\<turnstile>s \<midarrow>In2 e\<succ>\<rightarrow> (In2 vf, s')"
525 "G\<turnstile>s \<midarrow>e\<doteq>\<succ>v \<rightarrow> (x,s')" <= "G\<turnstile>s \<midarrow>In3 e\<succ>\<rightarrow> (In3 v ,x,s')"
526 "G\<turnstile>s \<midarrow>e\<doteq>\<succ>v \<rightarrow> s' " == "G\<turnstile>s \<midarrow>In3 e\<succ>\<rightarrow> (In3 v , s')"
527 "G\<turnstile>s \<midarrow>halloc oi\<succ>a\<rightarrow> (x,s')" <= "(s,oi,a,x,s') \<in> halloc G"
528 "G\<turnstile>s \<midarrow>halloc oi\<succ>a\<rightarrow> s' " == "(s,oi,a, s') \<in> halloc G"
529 "G\<turnstile>s \<midarrow>sxalloc\<rightarrow> (x,s')" <= "(s ,x,s') \<in> sxalloc G"
530 "G\<turnstile>s \<midarrow>sxalloc\<rightarrow> s' " == "(s , s') \<in> sxalloc G"
532 inductive "halloc G" intros (* allocating objects on the heap, cf. 12.5 *)
535 "G\<turnstile>(Some x,s) \<midarrow>halloc oi\<succ>arbitrary\<rightarrow> (Some x,s)"
537 New: "\<lbrakk>new_Addr (heap s) = Some a;
538 (x,oi') = (if atleast_free (heap s) (Suc (Suc 0)) then (None,oi)
539 else (Some (Xcpt (Loc a)),CInst (SXcpt OutOfMemory)))\<rbrakk>
541 G\<turnstile>Norm s \<midarrow>halloc oi\<succ>a\<rightarrow> (x,init_obj G oi' (Heap a) s)"
543 inductive "sxalloc G" intros (* allocating exception objects for
544 standard exceptions (other than OutOfMemory) *)
546 Norm: "G\<turnstile> Norm s \<midarrow>sxalloc\<rightarrow> Norm s"
548 XcptL: "G\<turnstile>(Some (Xcpt (Loc a) ),s) \<midarrow>sxalloc\<rightarrow> (Some (Xcpt (Loc a)),s)"
550 SXcpt: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>halloc (CInst (SXcpt xn))\<succ>a\<rightarrow> (x,s1)\<rbrakk> \<Longrightarrow>
551 G\<turnstile>(Some (Xcpt (Std xn)),s0) \<midarrow>sxalloc\<rightarrow> (Some (Xcpt (Loc a)),s1)"
553 inductive "eval G" intros
555 (* propagation of abrupt completion *)
559 "G\<turnstile>(Some xc,s) \<midarrow>t\<succ>\<rightarrow> (arbitrary3 t,(Some xc,s))"
562 (* execution of statements *)
565 Skip: "G\<turnstile>Norm s \<midarrow>Skip\<rightarrow> Norm s"
568 Expr: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>e-\<succ>v\<rightarrow> s1\<rbrakk> \<Longrightarrow>
569 G\<turnstile>Norm s0 \<midarrow>Expr e\<rightarrow> s1"
571 Lab: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>c \<rightarrow> s1\<rbrakk> \<Longrightarrow>
572 G\<turnstile>Norm s0 \<midarrow>l\<bullet> c\<rightarrow> abupd (absorb l) s1"
574 Comp: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>c1 \<rightarrow> s1;
575 G\<turnstile> s1 \<midarrow>c2 \<rightarrow> s2\<rbrakk> \<Longrightarrow>
576 G\<turnstile>Norm s0 \<midarrow>c1;; c2\<rightarrow> s2"
580 If: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>e-\<succ>b\<rightarrow> s1;
581 G\<turnstile> s1\<midarrow>(if the_Bool b then c1 else c2)\<rightarrow> s2\<rbrakk> \<Longrightarrow>
582 G\<turnstile>Norm s0 \<midarrow>If(e) c1 Else c2 \<rightarrow> s2"
584 (* cf. 14.10, 14.10.1 *)
585 (* G\<turnstile>Norm s0 \<midarrow>If(e) (c;; While(e) c) Else Skip\<rightarrow> s3 *)
586 (* A "continue jump" from the while body c is handled by
587 this rule. If a continue jump with the proper label was invoked inside c
588 this label (Cont l) is deleted out of the abrupt component of the state
589 before the iterative evaluation of the while statement.
590 A "break jump" is handled by the Lab Statement (Lab l (while\<dots>).
592 Loop: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>e-\<succ>b\<rightarrow> s1;
593 if normal s1 \<and> the_Bool b
594 then (G\<turnstile>s1 \<midarrow>c\<rightarrow> s2 \<and>
595 G\<turnstile>(abupd (absorb (Cont l)) s2) \<midarrow>l\<bullet> While(e) c\<rightarrow> s3)
596 else s3 = s1\<rbrakk> \<Longrightarrow>
597 G\<turnstile>Norm s0 \<midarrow>l\<bullet> While(e) c\<rightarrow> s3"
599 Do: "G\<turnstile>Norm s \<midarrow>Do j\<rightarrow> (Some (Jump j), s)"
602 Throw: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>e-\<succ>a'\<rightarrow> s1\<rbrakk> \<Longrightarrow>
603 G\<turnstile>Norm s0 \<midarrow>Throw e\<rightarrow> abupd (throw a') s1"
606 Try: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>c1\<rightarrow> s1; G\<turnstile>s1 \<midarrow>sxalloc\<rightarrow> s2;
607 if G,s2\<turnstile>catch C then G\<turnstile>new_xcpt_var vn s2 \<midarrow>c2\<rightarrow> s3 else s3 = s2\<rbrakk> \<Longrightarrow>
608 G\<turnstile>Norm s0 \<midarrow>Try c1 Catch(C vn) c2\<rightarrow> s3"
611 Fin: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>c1\<rightarrow> (x1,s1);
612 G\<turnstile>Norm s1 \<midarrow>c2\<rightarrow> s2;
613 s3=(if (\<exists> err. x1=Some (Error err))
615 else abupd (abrupt_if (x1\<noteq>None) x1) s2) \<rbrakk>
617 G\<turnstile>Norm s0 \<midarrow>c1 Finally c2\<rightarrow> s3"
618 (* cf. 12.4.2, 8.5 *)
619 Init: "\<lbrakk>the (class G C) = c;
620 if inited C (globs s0) then s3 = Norm s0
621 else (G\<turnstile>Norm (init_class_obj G C s0)
622 \<midarrow>(if C = Object then Skip else Init (super c))\<rightarrow> s1 \<and>
623 G\<turnstile>set_lvars empty s1 \<midarrow>init c\<rightarrow> s2 \<and> s3 = restore_lvars s1 s2)\<rbrakk>
625 G\<turnstile>Norm s0 \<midarrow>Init C\<rightarrow> s3"
626 (* This class initialisation rule is a little bit inaccurate. Look at the
628 1. The current class object (the static fields) are initialised
630 2. Then the superclasses are initialised
631 3. The static initialiser of the current class is invoked
632 More precisely we should expect another ordering, namely 2 1 3.
633 But we can't just naively toggle 1 and 2. By calling init_class_obj
634 before initialising the superclasses we also implicitly record that
635 we have started to initialise the current class (by setting an
636 value for the class object). This becomes
637 crucial for the completeness proof of the axiomatic semantics
638 (AxCompl.thy). Static initialisation requires an induction on the number
639 of classes not yet initialised (or to be more precise, classes where the
640 initialisation has not yet begun).
641 So we could first assign a dummy value to the class before
642 superclass initialisation and afterwards set the correct values.
643 But as long as we don't take memory overflow into account
644 when allocating class objects, and don't model definite assignment in
645 the static initialisers, we can leave things as they are for convenience.
647 (* evaluation of expressions *)
649 (* cf. 15.8.1, 12.4.1 *)
650 NewC: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>Init C\<rightarrow> s1;
651 G\<turnstile> s1 \<midarrow>halloc (CInst C)\<succ>a\<rightarrow> s2\<rbrakk> \<Longrightarrow>
652 G\<turnstile>Norm s0 \<midarrow>NewC C-\<succ>Addr a\<rightarrow> s2"
654 (* cf. 15.9.1, 12.4.1 *)
655 NewA: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>init_comp_ty T\<rightarrow> s1; G\<turnstile>s1 \<midarrow>e-\<succ>i'\<rightarrow> s2;
656 G\<turnstile>abupd (check_neg i') s2 \<midarrow>halloc (Arr T (the_Intg i'))\<succ>a\<rightarrow> s3\<rbrakk> \<Longrightarrow>
657 G\<turnstile>Norm s0 \<midarrow>New T[e]-\<succ>Addr a\<rightarrow> s3"
660 Cast: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>e-\<succ>v\<rightarrow> s1;
661 s2 = abupd (raise_if (\<not>G,store s1\<turnstile>v fits T) ClassCast) s1\<rbrakk> \<Longrightarrow>
662 G\<turnstile>Norm s0 \<midarrow>Cast T e-\<succ>v\<rightarrow> s2"
665 Inst: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>e-\<succ>v\<rightarrow> s1;
666 b = (v\<noteq>Null \<and> G,store s1\<turnstile>v fits RefT T)\<rbrakk> \<Longrightarrow>
667 G\<turnstile>Norm s0 \<midarrow>e InstOf T-\<succ>Bool b\<rightarrow> s1"
670 Lit: "G\<turnstile>Norm s \<midarrow>Lit v-\<succ>v\<rightarrow> Norm s"
672 UnOp: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>e-\<succ>v\<rightarrow> s1\<rbrakk>
673 \<Longrightarrow> G\<turnstile>Norm s0 \<midarrow>UnOp unop e-\<succ>(eval_unop unop v)\<rightarrow> s1"
675 BinOp: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>e1-\<succ>v1\<rightarrow> s1; G\<turnstile>s1 \<midarrow>e2-\<succ>v2\<rightarrow> s2\<rbrakk>
676 \<Longrightarrow> G\<turnstile>Norm s0 \<midarrow>BinOp binop e1 e2-\<succ>(eval_binop binop v1 v2)\<rightarrow> s2"
679 Super: "G\<turnstile>Norm s \<midarrow>Super-\<succ>val_this s\<rightarrow> Norm s"
682 Acc: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>va=\<succ>(v,f)\<rightarrow> s1\<rbrakk> \<Longrightarrow>
683 G\<turnstile>Norm s0 \<midarrow>Acc va-\<succ>v\<rightarrow> s1"
686 Ass: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>va=\<succ>(w,f)\<rightarrow> s1;
687 G\<turnstile> s1 \<midarrow>e-\<succ>v \<rightarrow> s2\<rbrakk> \<Longrightarrow>
688 G\<turnstile>Norm s0 \<midarrow>va:=e-\<succ>v\<rightarrow> assign f v s2"
691 Cond: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>e0-\<succ>b\<rightarrow> s1;
692 G\<turnstile> s1 \<midarrow>(if the_Bool b then e1 else e2)-\<succ>v\<rightarrow> s2\<rbrakk> \<Longrightarrow>
693 G\<turnstile>Norm s0 \<midarrow>e0 ? e1 : e2-\<succ>v\<rightarrow> s2"
696 (* cf. 15.11.4.1, 15.11.4.2, 15.11.4.4, 15.11.4.5 *)
698 "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>e-\<succ>a'\<rightarrow> s1; G\<turnstile>s1 \<midarrow>args\<doteq>\<succ>vs\<rightarrow> s2;
699 D = invocation_declclass G mode (store s2) a' statT \<lparr>name=mn,parTs=pTs\<rparr>;
700 s3=init_lvars G D \<lparr>name=mn,parTs=pTs\<rparr> mode a' vs s2;
701 s3' = check_method_access G accC statT mode \<lparr>name=mn,parTs=pTs\<rparr> a' s3;
702 G\<turnstile>s3' \<midarrow>Methd D \<lparr>name=mn,parTs=pTs\<rparr>-\<succ>v\<rightarrow> s4\<rbrakk>
704 G\<turnstile>Norm s0 \<midarrow>{accC,statT,mode}e\<cdot>mn({pTs}args)-\<succ>v\<rightarrow> (restore_lvars s2 s4)"
705 (* The accessibility check is after init_lvars, to keep it simple. Init_lvars
706 already tests for the absence of a null-pointer reference in case of an
707 instance method invocation
710 Methd: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>body G D sig-\<succ>v\<rightarrow> s1\<rbrakk> \<Longrightarrow>
711 G\<turnstile>Norm s0 \<midarrow>Methd D sig-\<succ>v\<rightarrow> s1"
712 (* The local variables l are just a dummy here. The are only used by
713 the smallstep semantics *)
714 (* cf. 14.15, 12.4.1 *)
715 Body: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>Init D\<rightarrow> s1; G\<turnstile>s1 \<midarrow>c\<rightarrow> s2\<rbrakk> \<Longrightarrow>
716 G\<turnstile>Norm s0 \<midarrow>Body D c
717 -\<succ>the (locals (store s2) Result)\<rightarrow>abupd (absorb Ret) s2"
718 (* The local variables l are just a dummy here. The are only used by
719 the smallstep semantics *)
720 (* evaluation of variables *)
722 (* cf. 15.13.1, 15.7.2 *)
723 LVar: "G\<turnstile>Norm s \<midarrow>LVar vn=\<succ>lvar vn s\<rightarrow> Norm s"
725 (* cf. 15.10.1, 12.4.1 *)
726 FVar: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>Init statDeclC\<rightarrow> s1; G\<turnstile>s1 \<midarrow>e-\<succ>a\<rightarrow> s2;
727 (v,s2') = fvar statDeclC stat fn a s2;
728 s3 = check_field_access G accC statDeclC fn stat a s2' \<rbrakk> \<Longrightarrow>
729 G\<turnstile>Norm s0 \<midarrow>{accC,statDeclC,stat}e..fn=\<succ>v\<rightarrow> s3"
730 (* The accessibility check is after fvar, to keep it simple. Fvar already
731 tests for the absence of a null-pointer reference in case of an instance
735 (* cf. 15.12.1, 15.25.1 *)
736 AVar: "\<lbrakk>G\<turnstile> Norm s0 \<midarrow>e1-\<succ>a\<rightarrow> s1; G\<turnstile>s1 \<midarrow>e2-\<succ>i\<rightarrow> s2;
737 (v,s2') = avar G i a s2\<rbrakk> \<Longrightarrow>
738 G\<turnstile>Norm s0 \<midarrow>e1.[e2]=\<succ>v\<rightarrow> s2'"
741 (* evaluation of expression lists *)
745 "G\<turnstile>Norm s0 \<midarrow>[]\<doteq>\<succ>[]\<rightarrow> Norm s0"
748 Cons: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>e -\<succ> v \<rightarrow> s1;
749 G\<turnstile> s1 \<midarrow>es\<doteq>\<succ>vs\<rightarrow> s2\<rbrakk> \<Longrightarrow>
750 G\<turnstile>Norm s0 \<midarrow>e#es\<doteq>\<succ>v#vs\<rightarrow> s2"
752 (* Rearrangement of premisses:
753 [0,1(Abrupt),2(Skip),8(Do),4(Lab),30(Nil),31(Cons),27(LVar),17(Cast),18(Inst),
754 17(Lit),18(UnOp),19(BinOp),20(Super),21(Acc),3(Expr),5(Comp),25(Methd),26(Body),23(Cond),6(If),
755 7(Loop),11(Fin),9(Throw),13(NewC),14(NewA),12(Init),22(Ass),10(Try),28(FVar),
759 bind_thm ("eval_induct_", rearrange_prems
760 [0,1,2,8,4,30,31,27,15,16,
761 17,18,19,20,21,3,5,25,26,23,6,
762 7,11,9,13,14,12,22,10,28,
763 29,24] (thm "eval.induct"))
768 lemmas eval_induct = eval_induct_ [split_format and and and and and and and and
769 and and and and and and s1 (* Acc *) and and s2 (* Comp *) and and and and
771 s2 (* Fin *) and and s2 (* NewC *)]
773 declare split_if [split del] split_if_asm [split del]
774 option.split [split del] option.split_asm [split del]
775 inductive_cases halloc_elim_cases:
776 "G\<turnstile>(Some xc,s) \<midarrow>halloc oi\<succ>a\<rightarrow> s'"
777 "G\<turnstile>(Norm s) \<midarrow>halloc oi\<succ>a\<rightarrow> s'"
779 inductive_cases sxalloc_elim_cases:
780 "G\<turnstile> Norm s \<midarrow>sxalloc\<rightarrow> s'"
781 "G\<turnstile>(Some (Xcpt (Loc a )),s) \<midarrow>sxalloc\<rightarrow> s'"
782 "G\<turnstile>(Some (Xcpt (Std xn)),s) \<midarrow>sxalloc\<rightarrow> s'"
783 inductive_cases sxalloc_cases: "G\<turnstile>s \<midarrow>sxalloc\<rightarrow> s'"
785 lemma sxalloc_elim_cases2: "\<lbrakk>G\<turnstile>s \<midarrow>sxalloc\<rightarrow> s';
786 \<And>s. \<lbrakk>s' = Norm s\<rbrakk> \<Longrightarrow> P;
787 \<And>a s. \<lbrakk>s' = (Some (Xcpt (Loc a)),s)\<rbrakk> \<Longrightarrow> P
788 \<rbrakk> \<Longrightarrow> P"
790 apply (erule sxalloc_cases)
794 declare not_None_eq [simp del] (* IntDef.Zero_def [simp del] *)
795 declare split_paired_All [simp del] split_paired_Ex [simp del]
797 simpset_ref() := simpset() delloop "split_all_tac"
799 inductive_cases eval_cases: "G\<turnstile>s \<midarrow>t\<succ>\<rightarrow> vs'"
801 inductive_cases eval_elim_cases:
802 "G\<turnstile>(Some xc,s) \<midarrow>t \<succ>\<rightarrow> vs'"
803 "G\<turnstile>Norm s \<midarrow>In1r Skip \<succ>\<rightarrow> xs'"
804 "G\<turnstile>Norm s \<midarrow>In1r (Do j) \<succ>\<rightarrow> xs'"
805 "G\<turnstile>Norm s \<midarrow>In1r (l\<bullet> c) \<succ>\<rightarrow> xs'"
806 "G\<turnstile>Norm s \<midarrow>In3 ([]) \<succ>\<rightarrow> vs'"
807 "G\<turnstile>Norm s \<midarrow>In3 (e#es) \<succ>\<rightarrow> vs'"
808 "G\<turnstile>Norm s \<midarrow>In1l (Lit w) \<succ>\<rightarrow> vs'"
809 "G\<turnstile>Norm s \<midarrow>In1l (UnOp unop e) \<succ>\<rightarrow> vs'"
810 "G\<turnstile>Norm s \<midarrow>In1l (BinOp binop e1 e2) \<succ>\<rightarrow> vs'"
811 "G\<turnstile>Norm s \<midarrow>In2 (LVar vn) \<succ>\<rightarrow> vs'"
812 "G\<turnstile>Norm s \<midarrow>In1l (Cast T e) \<succ>\<rightarrow> vs'"
813 "G\<turnstile>Norm s \<midarrow>In1l (e InstOf T) \<succ>\<rightarrow> vs'"
814 "G\<turnstile>Norm s \<midarrow>In1l (Super) \<succ>\<rightarrow> vs'"
815 "G\<turnstile>Norm s \<midarrow>In1l (Acc va) \<succ>\<rightarrow> vs'"
816 "G\<turnstile>Norm s \<midarrow>In1r (Expr e) \<succ>\<rightarrow> xs'"
817 "G\<turnstile>Norm s \<midarrow>In1r (c1;; c2) \<succ>\<rightarrow> xs'"
818 "G\<turnstile>Norm s \<midarrow>In1l (Methd C sig) \<succ>\<rightarrow> xs'"
819 "G\<turnstile>Norm s \<midarrow>In1l (Body D c) \<succ>\<rightarrow> xs'"
820 "G\<turnstile>Norm s \<midarrow>In1l (e0 ? e1 : e2) \<succ>\<rightarrow> vs'"
821 "G\<turnstile>Norm s \<midarrow>In1r (If(e) c1 Else c2) \<succ>\<rightarrow> xs'"
822 "G\<turnstile>Norm s \<midarrow>In1r (l\<bullet> While(e) c) \<succ>\<rightarrow> xs'"
823 "G\<turnstile>Norm s \<midarrow>In1r (c1 Finally c2) \<succ>\<rightarrow> xs'"
824 "G\<turnstile>Norm s \<midarrow>In1r (Throw e) \<succ>\<rightarrow> xs'"
825 "G\<turnstile>Norm s \<midarrow>In1l (NewC C) \<succ>\<rightarrow> vs'"
826 "G\<turnstile>Norm s \<midarrow>In1l (New T[e]) \<succ>\<rightarrow> vs'"
827 "G\<turnstile>Norm s \<midarrow>In1l (Ass va e) \<succ>\<rightarrow> vs'"
828 "G\<turnstile>Norm s \<midarrow>In1r (Try c1 Catch(tn vn) c2) \<succ>\<rightarrow> xs'"
829 "G\<turnstile>Norm s \<midarrow>In2 ({accC,statDeclC,stat}e..fn) \<succ>\<rightarrow> vs'"
830 "G\<turnstile>Norm s \<midarrow>In2 (e1.[e2]) \<succ>\<rightarrow> vs'"
831 "G\<turnstile>Norm s \<midarrow>In1l ({accC,statT,mode}e\<cdot>mn({pT}p)) \<succ>\<rightarrow> vs'"
832 "G\<turnstile>Norm s \<midarrow>In1r (Init C) \<succ>\<rightarrow> xs'"
833 declare not_None_eq [simp] (* IntDef.Zero_def [simp] *)
834 declare split_paired_All [simp] split_paired_Ex [simp]
836 simpset_ref() := simpset() addloop ("split_all_tac", split_all_tac)
838 declare split_if [split] split_if_asm [split]
839 option.split [split] option.split_asm [split]
842 "G\<turnstile>s \<midarrow>t\<succ>\<rightarrow> (w,s')
843 \<Longrightarrow> case t of
844 In1 ec \<Rightarrow> (case ec of
845 Inl e \<Rightarrow> (\<exists>v. w = In1 v)
846 | Inr c \<Rightarrow> w = \<diamondsuit>)
847 | In2 e \<Rightarrow> (\<exists>v. w = In2 v)
848 | In3 e \<Rightarrow> (\<exists>v. w = In3 v)"
849 apply (erule eval_cases)
851 apply (induct_tac "t")
852 apply (induct_tac "a")
858 fun eval_fun nam inj rhs =
860 val name = "eval_" ^ nam ^ "_eq"
861 val lhs = "G\<turnstile>s \<midarrow>" ^ inj ^ " t\<succ>\<rightarrow> (w, s')"
862 val () = qed_goal name (the_context()) (lhs ^ " = (" ^ rhs ^ ")")
863 (K [Auto_tac, ALLGOALS (ftac (thm "eval_Inj_elim")) THEN Auto_tac])
864 fun is_Inj (Const (inj,_) $ _) = true
866 fun pred (_ $ (Const ("Pair",_) $ _ $
867 (Const ("Pair", _) $ _ $ (Const ("Pair", _) $ x $ _ ))) $ _ ) = is_Inj x
869 make_simproc name lhs pred (thm name)
872 val eval_expr_proc =eval_fun "expr" "In1l" "\<exists>v. w=In1 v \<and> G\<turnstile>s \<midarrow>t-\<succ>v \<rightarrow> s'"
873 val eval_var_proc =eval_fun "var" "In2" "\<exists>vf. w=In2 vf \<and> G\<turnstile>s \<midarrow>t=\<succ>vf\<rightarrow> s'"
874 val eval_exprs_proc=eval_fun "exprs""In3" "\<exists>vs. w=In3 vs \<and> G\<turnstile>s \<midarrow>t\<doteq>\<succ>vs\<rightarrow> s'"
875 val eval_stmt_proc =eval_fun "stmt" "In1r" " w=\<diamondsuit> \<and> G\<turnstile>s \<midarrow>t \<rightarrow> s'";
876 Addsimprocs [eval_expr_proc,eval_var_proc,eval_exprs_proc,eval_stmt_proc];
877 bind_thms ("AbruptIs", sum3_instantiate (thm "eval.Abrupt"))
880 declare halloc.Abrupt [intro!] eval.Abrupt [intro!] AbruptIs [intro!]
882 text{* @{text Callee},@{text InsInitE}, @{text InsInitV}, @{text FinA} are only
883 used in smallstep semantics, not in the bigstep semantics. So their is no
884 valid evaluation of these terms
888 lemma eval_Callee: "G\<turnstile>Norm s\<midarrow>Callee l e-\<succ>v\<rightarrow> s' = False"
891 assume eval: "G\<turnstile>s \<midarrow>t\<succ>\<rightarrow> (v,s')" and
892 normal: "normal s" and
893 callee: "t=In1l (Callee l e)"
899 by (cases s') fastsimp
903 lemma eval_InsInitE: "G\<turnstile>Norm s\<midarrow>InsInitE c e-\<succ>v\<rightarrow> s' = False"
906 assume eval: "G\<turnstile>s \<midarrow>t\<succ>\<rightarrow> (v,s')" and
907 normal: "normal s" and
908 callee: "t=In1l (InsInitE c e)"
914 by (cases s') fastsimp
917 lemma eval_InsInitV: "G\<turnstile>Norm s\<midarrow>InsInitV c w=\<succ>v\<rightarrow> s' = False"
920 assume eval: "G\<turnstile>s \<midarrow>t\<succ>\<rightarrow> (v,s')" and
921 normal: "normal s" and
922 callee: "t=In2 (InsInitV c w)"
928 by (cases s') fastsimp
931 lemma eval_FinA: "G\<turnstile>Norm s\<midarrow>FinA a c\<rightarrow> s' = False"
934 assume eval: "G\<turnstile>s \<midarrow>t\<succ>\<rightarrow> (v,s')" and
935 normal: "normal s" and
936 callee: "t=In1r (FinA a c)"
942 by (cases s') fastsimp
945 lemma eval_no_abrupt_lemma:
946 "\<And>s s'. G\<turnstile>s \<midarrow>t\<succ>\<rightarrow> (w,s') \<Longrightarrow> normal s' \<longrightarrow> normal s"
947 by (erule eval_cases, auto)
949 lemma eval_no_abrupt:
950 "G\<turnstile>(x,s) \<midarrow>t\<succ>\<rightarrow> (w,Norm s') =
951 (x = None \<and> G\<turnstile>Norm s \<midarrow>t\<succ>\<rightarrow> (w,Norm s'))"
953 apply (frule eval_no_abrupt_lemma, auto)+
958 fun is_None (Const ("Datatype.option.None",_)) = true
960 fun pred (t as (_ $ (Const ("Pair",_) $
961 (Const ("Pair", _) $ x $ _) $ _ ) $ _)) = is_None x
963 val eval_no_abrupt_proc =
964 make_simproc "eval_no_abrupt" "G\<turnstile>(x,s) \<midarrow>e\<succ>\<rightarrow> (w,Norm s')" pred
965 (thm "eval_no_abrupt")
967 Addsimprocs [eval_no_abrupt_proc]
971 lemma eval_abrupt_lemma:
972 "G\<turnstile>s \<midarrow>t\<succ>\<rightarrow> (v,s') \<Longrightarrow> abrupt s=Some xc \<longrightarrow> s'= s \<and> v = arbitrary3 t"
973 by (erule eval_cases, auto)
976 " G\<turnstile>(Some xc,s) \<midarrow>t\<succ>\<rightarrow> (w,s') =
977 (s'=(Some xc,s) \<and> w=arbitrary3 t \<and>
978 G\<turnstile>(Some xc,s) \<midarrow>t\<succ>\<rightarrow> (arbitrary3 t,(Some xc,s)))"
980 apply (frule eval_abrupt_lemma, auto)+
985 fun is_Some (Const ("Pair",_) $ (Const ("Datatype.option.Some",_) $ _)$ _) =true
987 fun pred (_ $ (Const ("Pair",_) $
988 _ $ (Const ("Pair", _) $ _ $ (Const ("Pair", _) $ _ $
989 x))) $ _ ) = is_Some x
991 val eval_abrupt_proc =
992 make_simproc "eval_abrupt"
993 "G\<turnstile>(Some xc,s) \<midarrow>e\<succ>\<rightarrow> (w,s')" pred (thm "eval_abrupt")
995 Addsimprocs [eval_abrupt_proc]
999 lemma LitI: "G\<turnstile>s \<midarrow>Lit v-\<succ>(if normal s then v else arbitrary)\<rightarrow> s"
1000 apply (case_tac "s", case_tac "a = None")
1001 by (auto intro!: eval.Lit)
1003 lemma SkipI [intro!]: "G\<turnstile>s \<midarrow>Skip\<rightarrow> s"
1004 apply (case_tac "s", case_tac "a = None")
1005 by (auto intro!: eval.Skip)
1007 lemma ExprI: "G\<turnstile>s \<midarrow>e-\<succ>v\<rightarrow> s' \<Longrightarrow> G\<turnstile>s \<midarrow>Expr e\<rightarrow> s'"
1008 apply (case_tac "s", case_tac "a = None")
1009 by (auto intro!: eval.Expr)
1011 lemma CompI: "\<lbrakk>G\<turnstile>s \<midarrow>c1\<rightarrow> s1; G\<turnstile>s1 \<midarrow>c2\<rightarrow> s2\<rbrakk> \<Longrightarrow> G\<turnstile>s \<midarrow>c1;; c2\<rightarrow> s2"
1012 apply (case_tac "s", case_tac "a = None")
1013 by (auto intro!: eval.Comp)
1016 "\<And>s1. \<lbrakk>G\<turnstile>s \<midarrow>e-\<succ>b\<rightarrow> s1; G\<turnstile>s1 \<midarrow>(if the_Bool b then e1 else e2)-\<succ>v\<rightarrow> s2\<rbrakk> \<Longrightarrow>
1017 G\<turnstile>s \<midarrow>e ? e1 : e2-\<succ>(if normal s1 then v else arbitrary)\<rightarrow> s2"
1018 apply (case_tac "s", case_tac "a = None")
1019 by (auto intro!: eval.Cond)
1021 lemma IfI: "\<lbrakk>G\<turnstile>s \<midarrow>e-\<succ>v\<rightarrow> s1; G\<turnstile>s1 \<midarrow>(if the_Bool v then c1 else c2)\<rightarrow> s2\<rbrakk>
1022 \<Longrightarrow> G\<turnstile>s \<midarrow>If(e) c1 Else c2\<rightarrow> s2"
1023 apply (case_tac "s", case_tac "a = None")
1024 by (auto intro!: eval.If)
1026 lemma MethdI: "G\<turnstile>s \<midarrow>body G C sig-\<succ>v\<rightarrow> s'
1027 \<Longrightarrow> G\<turnstile>s \<midarrow>Methd C sig-\<succ>v\<rightarrow> s'"
1028 apply (case_tac "s", case_tac "a = None")
1029 by (auto intro!: eval.Methd)
1032 "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>e-\<succ>a'\<rightarrow> s1; G\<turnstile>s1 \<midarrow>ps\<doteq>\<succ>pvs\<rightarrow> s2;
1033 D = invocation_declclass G mode (store s2) a' statT \<lparr>name=mn,parTs=pTs\<rparr>;
1034 s3 = init_lvars G D \<lparr>name=mn,parTs=pTs\<rparr> mode a' pvs s2;
1035 s3' = check_method_access G accC statT mode \<lparr>name=mn,parTs=pTs\<rparr> a' s3;
1036 G\<turnstile>s3'\<midarrow>Methd D \<lparr>name=mn,parTs=pTs\<rparr>-\<succ> v\<rightarrow> s4;
1037 s4' = restore_lvars s2 s4\<rbrakk> \<Longrightarrow>
1038 G\<turnstile>Norm s0 \<midarrow>{accC,statT,mode}e\<cdot>mn({pTs}ps)-\<succ>v\<rightarrow> s4'"
1039 apply (drule eval.Call, assumption)
1040 apply (rule HOL.refl)
1045 "\<lbrakk>if inited C (globs s0) then s3 = Norm s0
1046 else G\<turnstile>Norm (init_class_obj G C s0)
1047 \<midarrow>(if C = Object then Skip else Init (super (the (class G C))))\<rightarrow> s1 \<and>
1048 G\<turnstile>set_lvars empty s1 \<midarrow>(init (the (class G C)))\<rightarrow> s2 \<and>
1049 s3 = restore_lvars s1 s2\<rbrakk> \<Longrightarrow>
1050 G\<turnstile>Norm s0 \<midarrow>Init C\<rightarrow> s3"
1051 apply (rule eval.Init)
1055 lemma init_done: "initd C s \<Longrightarrow> G\<turnstile>s \<midarrow>Init C\<rightarrow> s"
1056 apply (case_tac "s", simp)
1057 apply (case_tac "a")
1059 apply (rule eval_Init)
1064 "G\<turnstile>s \<midarrow>StatRef rt-\<succ>(if abrupt s=None then Null else arbitrary)\<rightarrow> s"
1065 apply (case_tac "s", simp)
1066 apply (case_tac "a = None")
1067 apply (auto del: eval.Abrupt intro!: eval.intros)
1071 lemma SkipD [dest!]: "G\<turnstile>s \<midarrow>Skip\<rightarrow> s' \<Longrightarrow> s' = s"
1072 apply (erule eval_cases)
1075 lemma Skip_eq [simp]: "G\<turnstile>s \<midarrow>Skip\<rightarrow> s' = (s = s')"
1079 lemma init_retains_locals [rule_format (no_asm)]: "G\<turnstile>s \<midarrow>t\<succ>\<rightarrow> (w,s') \<Longrightarrow>
1080 (\<forall>C. t=In1r (Init C) \<longrightarrow> locals (store s) = locals (store s'))"
1081 apply (erule eval.induct)
1082 apply (simp (no_asm_use) split del: split_if_asm option.split_asm)+
1086 lemma halloc_xcpt [dest!]:
1087 "\<And>s'. G\<turnstile>(Some xc,s) \<midarrow>halloc oi\<succ>a\<rightarrow> s' \<Longrightarrow> s'=(Some xc,s)"
1088 apply (erule_tac halloc_elim_cases)
1092 G\<turnstile>(x,(h,l)) \<midarrow>e\<succ>v\<rightarrow> (x',(h',l'))) \<Longrightarrow> l This = l' This"
1093 G\<turnstile>(x,(h,l)) \<midarrow>s \<rightarrow> (x',(h',l'))) \<Longrightarrow> l This = l' This"
1097 "G\<turnstile>s \<midarrow>In1l(body G C sig)\<succ>\<rightarrow> (w,s')
1098 \<Longrightarrow> G\<turnstile>s \<midarrow>In1l(Methd C sig)\<succ>\<rightarrow> (w,s')"
1099 apply (case_tac "s")
1100 apply (case_tac "a")
1102 apply (erule eval.Methd)
1103 apply (drule eval_abrupt_lemma)
1108 section "single valued"
1110 lemma unique_halloc [rule_format (no_asm)]:
1111 "\<And>s as as'. (s,oi,as)\<in>halloc G \<Longrightarrow> (s,oi,as')\<in>halloc G \<longrightarrow> as'=as"
1112 apply (simp (no_asm_simp) only: split_tupled_all)
1113 apply (erule halloc.induct)
1114 apply (auto elim!: halloc_elim_cases split del: split_if split_if_asm)
1115 apply (drule trans [THEN sym], erule sym)
1117 apply (drule trans [THEN sym], erule sym)
1122 lemma single_valued_halloc:
1123 "single_valued {((s,oi),(a,s')). G\<turnstile>s \<midarrow>halloc oi\<succ>a \<rightarrow> s'}"
1124 apply (unfold single_valued_def)
1125 by (clarsimp, drule (1) unique_halloc, auto)
1128 lemma unique_sxalloc [rule_format (no_asm)]:
1129 "\<And>s s'. G\<turnstile>s \<midarrow>sxalloc\<rightarrow> s' \<Longrightarrow> G\<turnstile>s \<midarrow>sxalloc\<rightarrow> s'' \<longrightarrow> s'' = s'"
1130 apply (simp (no_asm_simp) only: split_tupled_all)
1131 apply (erule sxalloc.induct)
1132 apply (auto dest: unique_halloc elim!: sxalloc_elim_cases
1133 split del: split_if split_if_asm)
1136 lemma single_valued_sxalloc: "single_valued {(s,s'). G\<turnstile>s \<midarrow>sxalloc\<rightarrow> s'}"
1137 apply (unfold single_valued_def)
1138 apply (blast dest: unique_sxalloc)
1141 lemma split_pairD: "(x,y) = p \<Longrightarrow> x = fst p & y = snd p"
1144 lemma eval_Body: "\<lbrakk>G\<turnstile>Norm s0 \<midarrow>Init D\<rightarrow> s1; G\<turnstile>s1 \<midarrow>c\<rightarrow> s2;
1145 res=the (locals (store s2) Result);
1146 s3=abupd (absorb Ret) s2\<rbrakk> \<Longrightarrow>
1147 G\<turnstile>Norm s0 \<midarrow>Body D c-\<succ>res\<rightarrow>s3"
1148 by (auto elim: eval.Body)
1150 lemma unique_eval [rule_format (no_asm)]:
1151 "G\<turnstile>s \<midarrow>t\<succ>\<rightarrow> ws \<Longrightarrow> (\<forall>ws'. G\<turnstile>s \<midarrow>t\<succ>\<rightarrow> ws' \<longrightarrow> ws' = ws)"
1152 apply (case_tac "ws")
1154 apply (erule thin_rl)
1155 apply (erule eval_induct)
1156 apply (tactic {* ALLGOALS (EVERY'
1157 [strip_tac, rotate_tac ~1, eresolve_tac (thms "eval_elim_cases")]) *})
1160 apply (simp (no_asm_use) only: split add: split_if_asm)
1162 prefer 30 (* Init *)
1163 apply (case_tac "inited C (globs s0)", (simp only: if_True if_False)+)
1164 prefer 26 (* While *)
1165 apply (simp (no_asm_use) only: split add: split_if_asm, blast)
1166 apply (drule_tac x="(In1 bb, s1a)" in spec, drule (1) mp, simp)
1167 apply (drule_tac x="(In1 bb, s1a)" in spec, drule (1) mp, simp)
1170 apply (blast dest: unique_sxalloc unique_halloc split_pairD)+
1174 lemma single_valued_eval:
1175 "single_valued {((s,t),vs'). G\<turnstile>s \<midarrow>t\<succ>\<rightarrow> vs'}"
1176 apply (unfold single_valued_def)
1177 by (clarify, drule (1) unique_eval, auto)