src/HOL/UNITY/Mutex.ML
changeset 5253 82a5ca6290aa
parent 5240 bbcd79ef7cf2
child 5277 e4297d03e5d2
equal deleted inserted replaced
5252:1b0f14d11142 5253:82a5ca6290aa
     7 *)
     7 *)
     8 
     8 
     9 (*split_all_tac causes a big blow-up*)
     9 (*split_all_tac causes a big blow-up*)
    10 claset_ref() := claset() delSWrapper "split_all_tac";
    10 claset_ref() := claset() delSWrapper "split_all_tac";
    11 
    11 
    12 val cmd_defs = [mutex_def, 
    12 val cmd_defs = [Mprg_def, 
    13 		cmd0U_def, cmd1U_def, cmd2U_def, cmd3U_def, cmd4U_def, 
    13 		cmd0U_def, cmd1U_def, cmd2U_def, cmd3U_def, cmd4U_def, 
    14 		cmd0V_def, cmd1V_def, cmd2V_def, cmd3V_def, cmd4V_def];
    14 		cmd0V_def, cmd1V_def, cmd2V_def, cmd3V_def, cmd4V_def];
    15 
    15 
    16 Goalw [mutex_def] "id : mutex";
    16 Goalw [Mprg_def] "id : Acts Mprg";
    17 by (Simp_tac 1);
    17 by (Simp_tac 1);
    18 qed "id_in_mutex";
    18 qed "id_in_Acts";
    19 AddIffs [id_in_mutex];
    19 AddIffs [id_in_Acts];
    20 
    20 
    21 
    21 
    22 (*Simplification for records*)
    22 (*Simplification for records*)
    23 val select_defs = thms"state.select_defs"
    23 val select_defs = thms"state.select_defs"
    24 and update_defs = thms"state.update_defs"
    24 and update_defs = thms"state.update_defs"
    28 
    28 
    29 
    29 
    30 Addsimps [invariantU_def, invariantV_def];
    30 Addsimps [invariantU_def, invariantV_def];
    31 
    31 
    32 
    32 
    33 Goalw [MInit_def] "invariant (MInit,mutex) invariantU";
    33 Goalw [Mprg_def] "invariant Mprg invariantU";
    34 by (rtac invariantI 1);
    34 by (rtac invariantI 1);
    35 by (constrains_tac cmd_defs 2);
    35 by (constrains_tac cmd_defs 2);
    36 by Auto_tac;
    36 by Auto_tac;
    37 qed "invariantU";
    37 qed "invariantU";
    38 
    38 
    39 Goalw [MInit_def] "invariant (MInit,mutex) invariantV";
    39 Goalw [Mprg_def] "invariant Mprg invariantV";
    40 by (rtac invariantI 1);
    40 by (rtac invariantI 1);
    41 by (constrains_tac cmd_defs 2);
    41 by (constrains_tac cmd_defs 2);
    42 by Auto_tac;
    42 by Auto_tac;
    43 qed "invariantV";
    43 qed "invariantV";
    44 
    44 
    45 val mutex_invariant = invariant_Int_rule [invariantU, invariantV];
    45 val invariantUV = invariant_Int_rule [invariantU, invariantV];
    46 
    46 
    47 
    47 
    48 (*The safety property: mutual exclusion*)
    48 (*The safety property: mutual exclusion*)
    49 Goal "disjoint (reachable (MInit,mutex)) {s. MM s = 3 & NN s = 3}";
    49 Goal "(reachable Mprg) Int {s. MM s = 3 & NN s = 3} = {}";
    50 by (cut_facts_tac [mutex_invariant RS invariant_includes_reachable] 1);
    50 by (cut_facts_tac [invariantUV RS invariant_includes_reachable] 1);
    51 by Auto_tac;
    51 by Auto_tac;
    52 qed "mutual_exclusion";
    52 qed "mutual_exclusion";
    53 
    53 
    54 
    54 
    55 (*The bad invariant FAILS in cmd1V*)
    55 (*The bad invariant FAILS in cmd1V*)
    56 Goalw [bad_invariantU_def] "stable mutex bad_invariantU";
    56 Goalw [bad_invariantU_def] "stable (Acts Mprg) bad_invariantU";
    57 by (constrains_tac cmd_defs 1);
    57 by (constrains_tac cmd_defs 1);
    58 by (REPEAT (trans_tac 1));
    58 by (REPEAT (trans_tac 1));
    59 by (safe_tac (claset() addSEs [le_SucE]));
    59 by (safe_tac (claset() addSEs [le_SucE]));
    60 by (Asm_full_simp_tac 1);
    60 by (Asm_full_simp_tac 1);
    61 (*Resulting state: n=1, p=false, m=4, u=false.  
    61 (*Resulting state: n=1, p=false, m=4, u=false.  
    65 getgoal 1;  
    65 getgoal 1;  
    66 
    66 
    67 
    67 
    68 (*** Progress for U ***)
    68 (*** Progress for U ***)
    69 
    69 
    70 Goalw [unless_def] "unless mutex {s. MM s=2} {s. MM s=3}";
    70 Goalw [unless_def] "unless (Acts Mprg) {s. MM s=2} {s. MM s=3}";
    71 by (constrains_tac cmd_defs 1);
    71 by (constrains_tac cmd_defs 1);
    72 qed "U_F0";
    72 qed "U_F0";
    73 
    73 
    74 Goal "LeadsTo(MInit,mutex) {s. MM s=1} {s. PP s = VV s & MM s = 2}";
    74 Goal "LeadsTo Mprg {s. MM s=1} {s. PP s = VV s & MM s = 2}";
    75 by (ensures_tac cmd_defs "cmd1U" 1);
    75 by (ensures_tac cmd_defs "cmd1U" 1);
    76 qed "U_F1";
    76 qed "U_F1";
    77 
    77 
    78 Goal "LeadsTo(MInit,mutex) {s. ~ PP s & MM s = 2} {s. MM s = 3}";
    78 Goal "LeadsTo Mprg {s. ~ PP s & MM s = 2} {s. MM s = 3}";
    79 by (cut_facts_tac [mutex_invariant] 1);
    79 by (cut_facts_tac [invariantUV] 1);
       
    80 bw Mprg_def;
    80 by (ensures_tac cmd_defs "cmd2U" 1);
    81 by (ensures_tac cmd_defs "cmd2U" 1);
    81 qed "U_F2";
    82 qed "U_F2";
    82 
    83 
    83 Goalw [mutex_def] "LeadsTo(MInit,mutex) {s. MM s = 3} {s. PP s}";
    84 Goal "LeadsTo Mprg {s. MM s = 3} {s. PP s}";
    84 by (rtac leadsTo_imp_LeadsTo 1); 
    85 by (rtac leadsTo_imp_LeadsTo 1); 
    85 by (res_inst_tac [("B", "{s. MM s = 4}")] leadsTo_Trans 1);
    86 by (res_inst_tac [("B", "{s. MM s = 4}")] leadsTo_Trans 1);
    86 by (ensures_tac cmd_defs "cmd4U" 2);
    87 by (ensures_tac cmd_defs "cmd4U" 2);
    87 by (ensures_tac cmd_defs "cmd3U" 1);
    88 by (ensures_tac cmd_defs "cmd3U" 1);
    88 qed "U_F3";
    89 qed "U_F3";
    89 
    90 
    90 Goal "LeadsTo(MInit,mutex) {s. MM s = 2} {s. PP s}";
    91 Goal "LeadsTo Mprg {s. MM s = 2} {s. PP s}";
    91 by (rtac ([LeadsTo_weaken_L, subset_refl RS subset_imp_LeadsTo] 
    92 by (rtac ([LeadsTo_weaken_L, subset_refl RS subset_imp_LeadsTo] 
    92 	  MRS LeadsTo_Diff) 1);
    93 	  MRS LeadsTo_Diff) 1);
    93 by (rtac ([U_F2, U_F3] MRS LeadsTo_Trans) 1);
    94 by (rtac ([U_F2, U_F3] MRS LeadsTo_Trans) 1);
    94 by (auto_tac (claset() addSEs [less_SucE], simpset()));
    95 by (auto_tac (claset() addSEs [less_SucE], simpset()));
    95 val U_lemma2 = result();
    96 val U_lemma2 = result();
    96 
    97 
    97 Goal "LeadsTo(MInit,mutex) {s. MM s = 1} {s. PP s}";
    98 Goal "LeadsTo Mprg {s. MM s = 1} {s. PP s}";
    98 by (rtac ([U_F1 RS LeadsTo_weaken_R, U_lemma2] MRS LeadsTo_Trans) 1);
    99 by (rtac ([U_F1 RS LeadsTo_weaken_R, U_lemma2] MRS LeadsTo_Trans) 1);
    99 by (Blast_tac 1);
   100 by (Blast_tac 1);
   100 val U_lemma1 = result();
   101 val U_lemma1 = result();
   101 
   102 
   102 
   103 Goal "LeadsTo Mprg {s. 1 <= MM s & MM s <= 3} {s. PP s}";
   103 Goal "LeadsTo(MInit,mutex) {s. 1 <= MM s & MM s <= 3} {s. PP s}";
       
   104 by (simp_tac (simpset() addsimps [le_Suc_eq, conj_disj_distribL] 
   104 by (simp_tac (simpset() addsimps [le_Suc_eq, conj_disj_distribL] 
   105 	                addcongs [rev_conj_cong]) 1);
   105 	                addcongs [rev_conj_cong]) 1);
   106 by (simp_tac (simpset() addsimps [Collect_disj_eq, LeadsTo_Un_distrib,
   106 by (simp_tac (simpset() addsimps [Collect_disj_eq, LeadsTo_Un_distrib,
   107 				  U_lemma1, U_lemma2, U_F3] ) 1);
   107 				  U_lemma1, U_lemma2, U_F3] ) 1);
   108 val U_lemma123 = result();
   108 val U_lemma123 = result();
   109 
   109 
   110 
       
   111 (*Misra's F4*)
   110 (*Misra's F4*)
   112 Goal "LeadsTo(MInit,mutex) {s. UU s} {s. PP s}";
   111 Goal "LeadsTo Mprg {s. UU s} {s. PP s}";
   113 by (rtac ([invariantU, U_lemma123] MRS invariant_LeadsTo_weaken) 1);
   112 by (rtac ([invariantU, U_lemma123] MRS invariant_LeadsTo_weaken) 1);
   114 by Auto_tac;
   113 by Auto_tac;
   115 qed "u_leadsto_p";
   114 qed "u_leadsto_p";
   116 
   115 
   117 
   116 
   118 (*** Progress for V ***)
   117 (*** Progress for V ***)
   119 
   118 
   120 
   119 
   121 Goalw [unless_def] "unless mutex {s. NN s=2} {s. NN s=3}";
   120 Goalw [unless_def] "unless (Acts Mprg) {s. NN s=2} {s. NN s=3}";
   122 by (constrains_tac cmd_defs 1);
   121 by (constrains_tac cmd_defs 1);
   123 qed "V_F0";
   122 qed "V_F0";
   124 
   123 
   125 Goal "LeadsTo(MInit,mutex) {s. NN s=1} {s. PP s = (~ UU s) & NN s = 2}";
   124 Goal "LeadsTo Mprg {s. NN s=1} {s. PP s = (~ UU s) & NN s = 2}";
   126 by (ensures_tac cmd_defs "cmd1V" 1);
   125 by (ensures_tac cmd_defs "cmd1V" 1);
   127 qed "V_F1";
   126 qed "V_F1";
   128 
   127 
   129 Goal "LeadsTo(MInit,mutex) {s. PP s & NN s = 2} {s. NN s = 3}";
   128 Goal "LeadsTo Mprg {s. PP s & NN s = 2} {s. NN s = 3}";
   130 by (cut_facts_tac [mutex_invariant] 1);
   129 by (cut_facts_tac [invariantUV] 1);
   131 by (ensures_tac cmd_defs "cmd2V" 1);
   130 by (ensures_tac cmd_defs "cmd2V" 1);
   132 qed "V_F2";
   131 qed "V_F2";
   133 
   132 
   134 Goalw [mutex_def] "LeadsTo(MInit,mutex) {s. NN s = 3} {s. ~ PP s}";
   133 Goal "LeadsTo Mprg {s. NN s = 3} {s. ~ PP s}";
   135 by (rtac leadsTo_imp_LeadsTo 1); 
   134 by (rtac leadsTo_imp_LeadsTo 1); 
   136 by (res_inst_tac [("B", "{s. NN s = 4}")] leadsTo_Trans 1);
   135 by (res_inst_tac [("B", "{s. NN s = 4}")] leadsTo_Trans 1);
   137 by (ensures_tac cmd_defs "cmd4V" 2);
   136 by (ensures_tac cmd_defs "cmd4V" 2);
   138 by (ensures_tac cmd_defs "cmd3V" 1);
   137 by (ensures_tac cmd_defs "cmd3V" 1);
   139 qed "V_F3";
   138 qed "V_F3";
   140 
   139 
   141 Goal "LeadsTo(MInit,mutex) {s. NN s = 2} {s. ~ PP s}";
   140 Goal "LeadsTo Mprg {s. NN s = 2} {s. ~ PP s}";
   142 by (rtac ([LeadsTo_weaken_L, subset_refl RS subset_imp_LeadsTo] 
   141 by (rtac ([LeadsTo_weaken_L, subset_refl RS subset_imp_LeadsTo] 
   143 	  MRS LeadsTo_Diff) 1);
   142 	  MRS LeadsTo_Diff) 1);
   144 by (rtac ([V_F2, V_F3] MRS LeadsTo_Trans) 1);
   143 by (rtac ([V_F2, V_F3] MRS LeadsTo_Trans) 1);
   145 by (auto_tac (claset() addSEs [less_SucE], simpset()));
   144 by (auto_tac (claset() addSEs [less_SucE], simpset()));
   146 val V_lemma2 = result();
   145 val V_lemma2 = result();
   147 
   146 
   148 Goal "LeadsTo(MInit,mutex) {s. NN s = 1} {s. ~ PP s}";
   147 Goal "LeadsTo Mprg {s. NN s = 1} {s. ~ PP s}";
   149 by (rtac ([V_F1 RS LeadsTo_weaken_R, V_lemma2] MRS LeadsTo_Trans) 1);
   148 by (rtac ([V_F1 RS LeadsTo_weaken_R, V_lemma2] MRS LeadsTo_Trans) 1);
   150 by (Blast_tac 1);
   149 by (Blast_tac 1);
   151 val V_lemma1 = result();
   150 val V_lemma1 = result();
   152 
   151 
   153 Goal "LeadsTo(MInit,mutex) {s. 1 <= NN s & NN s <= 3} {s. ~ PP s}";
   152 Goal "LeadsTo Mprg {s. 1 <= NN s & NN s <= 3} {s. ~ PP s}";
   154 by (simp_tac (simpset() addsimps [le_Suc_eq, conj_disj_distribL] 
   153 by (simp_tac (simpset() addsimps [le_Suc_eq, conj_disj_distribL] 
   155 	                addcongs [rev_conj_cong]) 1);
   154 	                addcongs [rev_conj_cong]) 1);
   156 by (simp_tac (simpset() addsimps [Collect_disj_eq, LeadsTo_Un_distrib,
   155 by (simp_tac (simpset() addsimps [Collect_disj_eq, LeadsTo_Un_distrib,
   157 				  V_lemma1, V_lemma2, V_F3] ) 1);
   156 				  V_lemma1, V_lemma2, V_F3] ) 1);
   158 val V_lemma123 = result();
   157 val V_lemma123 = result();
   159 
   158 
   160 
   159 
   161 (*Misra's F4*)
   160 (*Misra's F4*)
   162 Goal "LeadsTo(MInit,mutex) {s. VV s} {s. ~ PP s}";
   161 Goal "LeadsTo Mprg {s. VV s} {s. ~ PP s}";
   163 by (rtac ([invariantV, V_lemma123] MRS invariant_LeadsTo_weaken) 1);
   162 by (rtac ([invariantV, V_lemma123] MRS invariant_LeadsTo_weaken) 1);
   164 by Auto_tac;
   163 by Auto_tac;
   165 qed "v_leadsto_not_p";
   164 qed "v_leadsto_not_p";
   166 
   165 
   167 
   166 
   168 (** Absence of starvation **)
   167 (** Absence of starvation **)
   169 
   168 
   170 (*Misra's F6*)
   169 (*Misra's F6*)
   171 Goal "LeadsTo(MInit,mutex) {s. MM s = 1} {s. MM s = 3}";
   170 Goal "LeadsTo Mprg {s. MM s = 1} {s. MM s = 3}";
   172 by (rtac LeadsTo_Un_duplicate 1);
   171 by (rtac LeadsTo_Un_duplicate 1);
   173 by (rtac LeadsTo_cancel2 1);
   172 by (rtac LeadsTo_cancel2 1);
   174 by (rtac U_F2 2);
   173 by (rtac U_F2 2);
   175 by (simp_tac (simpset() addsimps [Collect_conj_eq] ) 1);
   174 by (simp_tac (simpset() addsimps [Collect_conj_eq] ) 1);
   176 by (stac Un_commute 1);
   175 by (stac Un_commute 1);
   180 by (auto_tac (claset() addSEs [less_SucE], simpset()));
   179 by (auto_tac (claset() addSEs [less_SucE], simpset()));
   181 qed "m1_leadsto_3";
   180 qed "m1_leadsto_3";
   182 
   181 
   183 
   182 
   184 (*The same for V*)
   183 (*The same for V*)
   185 Goal "LeadsTo(MInit,mutex) {s. NN s = 1} {s. NN s = 3}";
   184 Goal "LeadsTo Mprg {s. NN s = 1} {s. NN s = 3}";
   186 by (rtac LeadsTo_Un_duplicate 1);
   185 by (rtac LeadsTo_Un_duplicate 1);
   187 by (rtac LeadsTo_cancel2 1);
   186 by (rtac LeadsTo_cancel2 1);
   188 by (rtac V_F2 2);
   187 by (rtac V_F2 2);
   189 by (simp_tac (simpset() addsimps [Collect_conj_eq] ) 1);
   188 by (simp_tac (simpset() addsimps [Collect_conj_eq] ) 1);
   190 by (stac Un_commute 1);
   189 by (stac Un_commute 1);