1 theory PIPBasics |
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2 imports PIPDefs |
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3 begin |
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4 |
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5 locale valid_trace = |
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6 fixes s |
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7 assumes vt : "vt s" |
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8 |
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9 locale valid_trace_e = valid_trace + |
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10 fixes e |
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11 assumes vt_e: "vt (e#s)" |
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12 begin |
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13 |
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14 lemma pip_e: "PIP s e" |
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15 using vt_e by (cases, simp) |
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16 |
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17 end |
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18 |
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19 lemma runing_ready: |
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20 shows "runing s \<subseteq> readys s" |
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21 unfolding runing_def readys_def |
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22 by auto |
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23 |
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24 lemma readys_threads: |
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25 shows "readys s \<subseteq> threads s" |
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26 unfolding readys_def |
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27 by auto |
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28 |
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29 lemma wq_v_neq: |
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30 "cs \<noteq> cs' \<Longrightarrow> wq (V thread cs#s) cs' = wq s cs'" |
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31 by (auto simp:wq_def Let_def cp_def split:list.splits) |
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32 |
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33 context valid_trace |
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34 begin |
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35 |
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36 lemma actor_inv: |
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37 assumes "PIP s e" |
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38 and "\<not> isCreate e" |
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39 shows "actor e \<in> runing s" |
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40 using assms |
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41 by (induct, auto) |
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42 |
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43 lemma ind [consumes 0, case_names Nil Cons, induct type]: |
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44 assumes "PP []" |
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45 and "(\<And>s e. valid_trace s \<Longrightarrow> valid_trace (e#s) \<Longrightarrow> |
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46 PP s \<Longrightarrow> PIP s e \<Longrightarrow> PP (e # s))" |
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47 shows "PP s" |
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48 proof(rule vt.induct[OF vt]) |
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49 from assms(1) show "PP []" . |
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50 next |
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51 fix s e |
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52 assume h: "vt s" "PP s" "PIP s e" |
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53 show "PP (e # s)" |
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54 proof(cases rule:assms(2)) |
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55 from h(1) show v1: "valid_trace s" by (unfold_locales, simp) |
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56 next |
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57 from h(1,3) have "vt (e#s)" by auto |
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58 thus "valid_trace (e # s)" by (unfold_locales, simp) |
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59 qed (insert h, auto) |
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60 qed |
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61 |
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62 lemma wq_distinct: "distinct (wq s cs)" |
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63 proof(rule ind, simp add:wq_def) |
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64 fix s e |
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65 assume h1: "step s e" |
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66 and h2: "distinct (wq s cs)" |
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67 thus "distinct (wq (e # s) cs)" |
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68 proof(induct rule:step.induct, auto simp: wq_def Let_def split:list.splits) |
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69 fix thread s |
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70 assume h1: "(Cs cs, Th thread) \<notin> (RAG s)\<^sup>+" |
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71 and h2: "thread \<in> set (wq_fun (schs s) cs)" |
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72 and h3: "thread \<in> runing s" |
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73 show "False" |
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74 proof - |
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75 from h3 have "\<And> cs. thread \<in> set (wq_fun (schs s) cs) \<Longrightarrow> |
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76 thread = hd ((wq_fun (schs s) cs))" |
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77 by (simp add:runing_def readys_def s_waiting_def wq_def) |
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78 from this [OF h2] have "thread = hd (wq_fun (schs s) cs)" . |
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79 with h2 |
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80 have "(Cs cs, Th thread) \<in> (RAG s)" |
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81 by (simp add:s_RAG_def s_holding_def wq_def cs_holding_def) |
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82 with h1 show False by auto |
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83 qed |
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84 next |
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85 fix thread s a list |
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86 assume dst: "distinct list" |
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87 show "distinct (SOME q. distinct q \<and> set q = set list)" |
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88 proof(rule someI2) |
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89 from dst show "distinct list \<and> set list = set list" by auto |
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90 next |
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91 fix q assume "distinct q \<and> set q = set list" |
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92 thus "distinct q" by auto |
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93 qed |
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94 qed |
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95 qed |
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96 |
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97 end |
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98 |
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99 |
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100 context valid_trace_e |
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101 begin |
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102 |
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103 text {* |
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104 The following lemma shows that only the @{text "P"} |
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105 operation can add new thread into waiting queues. |
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106 Such kind of lemmas are very obvious, but need to be checked formally. |
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107 This is a kind of confirmation that our modelling is correct. |
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108 *} |
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109 |
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110 lemma block_pre: |
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111 assumes s_ni: "thread \<notin> set (wq s cs)" |
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112 and s_i: "thread \<in> set (wq (e#s) cs)" |
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113 shows "e = P thread cs" |
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114 proof - |
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115 show ?thesis |
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116 proof(cases e) |
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117 case (P th cs) |
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118 with assms |
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119 show ?thesis |
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120 by (auto simp:wq_def Let_def split:if_splits) |
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121 next |
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122 case (Create th prio) |
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123 with assms show ?thesis |
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124 by (auto simp:wq_def Let_def split:if_splits) |
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125 next |
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126 case (Exit th) |
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127 with assms show ?thesis |
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128 by (auto simp:wq_def Let_def split:if_splits) |
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129 next |
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130 case (Set th prio) |
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131 with assms show ?thesis |
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132 by (auto simp:wq_def Let_def split:if_splits) |
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133 next |
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134 case (V th cs) |
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135 with vt_e assms show ?thesis |
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136 apply (auto simp:wq_def Let_def split:if_splits) |
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137 proof - |
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138 fix q qs |
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139 assume h1: "thread \<notin> set (wq_fun (schs s) cs)" |
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140 and h2: "q # qs = wq_fun (schs s) cs" |
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141 and h3: "thread \<in> set (SOME q. distinct q \<and> set q = set qs)" |
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142 and vt: "vt (V th cs # s)" |
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143 from h1 and h2[symmetric] have "thread \<notin> set (q # qs)" by simp |
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144 moreover have "thread \<in> set qs" |
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145 proof - |
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146 have "set (SOME q. distinct q \<and> set q = set qs) = set qs" |
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147 proof(rule someI2) |
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148 from wq_distinct [of cs] |
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149 and h2[symmetric, folded wq_def] |
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150 show "distinct qs \<and> set qs = set qs" by auto |
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151 next |
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152 fix x assume "distinct x \<and> set x = set qs" |
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153 thus "set x = set qs" by auto |
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154 qed |
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155 with h3 show ?thesis by simp |
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156 qed |
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157 ultimately show "False" by auto |
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158 qed |
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159 qed |
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160 qed |
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161 |
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162 end |
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163 |
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164 text {* |
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165 The following lemmas is also obvious and shallow. It says |
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166 that only running thread can request for a critical resource |
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167 and that the requested resource must be one which is |
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168 not current held by the thread. |
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169 *} |
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170 |
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171 lemma p_pre: "\<lbrakk>vt ((P thread cs)#s)\<rbrakk> \<Longrightarrow> |
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172 thread \<in> runing s \<and> (Cs cs, Th thread) \<notin> (RAG s)^+" |
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173 apply (ind_cases "vt ((P thread cs)#s)") |
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174 apply (ind_cases "step s (P thread cs)") |
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175 by auto |
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176 |
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177 lemma abs1: |
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178 assumes ein: "e \<in> set es" |
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179 and neq: "hd es \<noteq> hd (es @ [x])" |
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180 shows "False" |
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181 proof - |
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182 from ein have "es \<noteq> []" by auto |
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183 then obtain e ess where "es = e # ess" by (cases es, auto) |
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184 with neq show ?thesis by auto |
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185 qed |
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186 |
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187 lemma q_head: "Q (hd es) \<Longrightarrow> hd es = hd [th\<leftarrow>es . Q th]" |
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188 by (cases es, auto) |
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189 |
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190 inductive_cases evt_cons: "vt (a#s)" |
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191 |
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192 context valid_trace_e |
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193 begin |
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194 |
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195 lemma abs2: |
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196 assumes inq: "thread \<in> set (wq s cs)" |
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197 and nh: "thread = hd (wq s cs)" |
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198 and qt: "thread \<noteq> hd (wq (e#s) cs)" |
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199 and inq': "thread \<in> set (wq (e#s) cs)" |
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200 shows "False" |
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201 proof - |
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202 from vt_e assms show "False" |
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203 apply (cases e) |
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204 apply ((simp split:if_splits add:Let_def wq_def)[1])+ |
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205 apply (insert abs1, fast)[1] |
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206 apply (auto simp:wq_def simp:Let_def split:if_splits list.splits) |
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207 proof - |
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208 fix th qs |
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209 assume vt: "vt (V th cs # s)" |
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210 and th_in: "thread \<in> set (SOME q. distinct q \<and> set q = set qs)" |
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211 and eq_wq: "wq_fun (schs s) cs = thread # qs" |
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212 show "False" |
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213 proof - |
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214 from wq_distinct[of cs] |
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215 and eq_wq[folded wq_def] have "distinct (thread#qs)" by simp |
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216 moreover have "thread \<in> set qs" |
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217 proof - |
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218 have "set (SOME q. distinct q \<and> set q = set qs) = set qs" |
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219 proof(rule someI2) |
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220 from wq_distinct [of cs] |
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221 and eq_wq [folded wq_def] |
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222 show "distinct qs \<and> set qs = set qs" by auto |
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223 next |
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224 fix x assume "distinct x \<and> set x = set qs" |
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225 thus "set x = set qs" by auto |
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226 qed |
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227 with th_in show ?thesis by auto |
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228 qed |
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229 ultimately show ?thesis by auto |
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230 qed |
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231 qed |
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232 qed |
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233 |
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234 end |
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235 |
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236 context valid_trace |
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237 begin |
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238 |
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239 lemma vt_moment: "\<And> t. vt (moment t s)" |
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240 proof(induct rule:ind) |
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241 case Nil |
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242 thus ?case by (simp add:vt_nil) |
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243 next |
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244 case (Cons s e t) |
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245 show ?case |
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246 proof(cases "t \<ge> length (e#s)") |
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247 case True |
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248 from True have "moment t (e#s) = e#s" by simp |
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249 thus ?thesis using Cons |
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250 by (simp add:valid_trace_def) |
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251 next |
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252 case False |
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253 from Cons have "vt (moment t s)" by simp |
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254 moreover have "moment t (e#s) = moment t s" |
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255 proof - |
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256 from False have "t \<le> length s" by simp |
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257 from moment_app [OF this, of "[e]"] |
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258 show ?thesis by simp |
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259 qed |
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260 ultimately show ?thesis by simp |
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261 qed |
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262 qed |
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263 |
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264 (* Wrong: |
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265 lemma \<lbrakk>thread \<in> set (wq_fun cs1 s); thread \<in> set (wq_fun cs2 s)\<rbrakk> \<Longrightarrow> cs1 = cs2" |
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266 *) |
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267 |
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268 text {* (* ddd *) |
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269 The nature of the work is like this: since it starts from a very simple and basic |
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270 model, even intuitively very `basic` and `obvious` properties need to derived from scratch. |
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271 For instance, the fact |
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272 that one thread can not be blocked by two critical resources at the same time |
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273 is obvious, because only running threads can make new requests, if one is waiting for |
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274 a critical resource and get blocked, it can not make another resource request and get |
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275 blocked the second time (because it is not running). |
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276 |
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277 To derive this fact, one needs to prove by contraction and |
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278 reason about time (or @{text "moement"}). The reasoning is based on a generic theorem |
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279 named @{text "p_split"}, which is about status changing along the time axis. It says if |
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280 a condition @{text "Q"} is @{text "True"} at a state @{text "s"}, |
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281 but it was @{text "False"} at the very beginning, then there must exits a moment @{text "t"} |
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282 in the history of @{text "s"} (notice that @{text "s"} itself is essentially the history |
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283 of events leading to it), such that @{text "Q"} switched |
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284 from being @{text "False"} to @{text "True"} and kept being @{text "True"} |
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285 till the last moment of @{text "s"}. |
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286 |
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287 Suppose a thread @{text "th"} is blocked |
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288 on @{text "cs1"} and @{text "cs2"} in some state @{text "s"}, |
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289 since no thread is blocked at the very beginning, by applying |
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290 @{text "p_split"} to these two blocking facts, there exist |
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291 two moments @{text "t1"} and @{text "t2"} in @{text "s"}, such that |
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292 @{text "th"} got blocked on @{text "cs1"} and @{text "cs2"} |
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293 and kept on blocked on them respectively ever since. |
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294 |
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295 Without lose of generality, we assume @{text "t1"} is earlier than @{text "t2"}. |
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296 However, since @{text "th"} was blocked ever since memonent @{text "t1"}, so it was still |
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297 in blocked state at moment @{text "t2"} and could not |
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298 make any request and get blocked the second time: Contradiction. |
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299 *} |
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300 |
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301 lemma waiting_unique_pre: |
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302 assumes h11: "thread \<in> set (wq s cs1)" |
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303 and h12: "thread \<noteq> hd (wq s cs1)" |
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304 assumes h21: "thread \<in> set (wq s cs2)" |
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305 and h22: "thread \<noteq> hd (wq s cs2)" |
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306 and neq12: "cs1 \<noteq> cs2" |
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307 shows "False" |
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308 proof - |
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309 let "?Q cs s" = "thread \<in> set (wq s cs) \<and> thread \<noteq> hd (wq s cs)" |
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310 from h11 and h12 have q1: "?Q cs1 s" by simp |
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311 from h21 and h22 have q2: "?Q cs2 s" by simp |
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312 have nq1: "\<not> ?Q cs1 []" by (simp add:wq_def) |
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313 have nq2: "\<not> ?Q cs2 []" by (simp add:wq_def) |
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314 from p_split [of "?Q cs1", OF q1 nq1] |
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315 obtain t1 where lt1: "t1 < length s" |
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316 and np1: "\<not>(thread \<in> set (wq (moment t1 s) cs1) \<and> |
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317 thread \<noteq> hd (wq (moment t1 s) cs1))" |
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318 and nn1: "(\<forall>i'>t1. thread \<in> set (wq (moment i' s) cs1) \<and> |
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319 thread \<noteq> hd (wq (moment i' s) cs1))" by auto |
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320 from p_split [of "?Q cs2", OF q2 nq2] |
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321 obtain t2 where lt2: "t2 < length s" |
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322 and np2: "\<not>(thread \<in> set (wq (moment t2 s) cs2) \<and> |
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323 thread \<noteq> hd (wq (moment t2 s) cs2))" |
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324 and nn2: "(\<forall>i'>t2. thread \<in> set (wq (moment i' s) cs2) \<and> |
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325 thread \<noteq> hd (wq (moment i' s) cs2))" by auto |
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326 show ?thesis |
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327 proof - |
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328 { |
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329 assume lt12: "t1 < t2" |
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330 let ?t3 = "Suc t2" |
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331 from lt2 have le_t3: "?t3 \<le> length s" by auto |
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332 from moment_plus [OF this] |
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333 obtain e where eq_m: "moment ?t3 s = e#moment t2 s" by auto |
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334 have "t2 < ?t3" by simp |
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335 from nn2 [rule_format, OF this] and eq_m |
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336 have h1: "thread \<in> set (wq (e#moment t2 s) cs2)" and |
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337 h2: "thread \<noteq> hd (wq (e#moment t2 s) cs2)" by auto |
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338 have "vt (e#moment t2 s)" |
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339 proof - |
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340 from vt_moment |
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341 have "vt (moment ?t3 s)" . |
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342 with eq_m show ?thesis by simp |
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343 qed |
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344 then interpret vt_e: valid_trace_e "moment t2 s" "e" |
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345 by (unfold_locales, auto, cases, simp) |
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346 have ?thesis |
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347 proof(cases "thread \<in> set (wq (moment t2 s) cs2)") |
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348 case True |
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349 from True and np2 have eq_th: "thread = hd (wq (moment t2 s) cs2)" |
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350 by auto |
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351 from vt_e.abs2 [OF True eq_th h2 h1] |
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352 show ?thesis by auto |
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353 next |
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354 case False |
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355 from vt_e.block_pre[OF False h1] |
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356 have "e = P thread cs2" . |
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357 with vt_e.vt_e have "vt ((P thread cs2)# moment t2 s)" by simp |
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358 from p_pre [OF this] have "thread \<in> runing (moment t2 s)" by simp |
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359 with runing_ready have "thread \<in> readys (moment t2 s)" by auto |
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360 with nn1 [rule_format, OF lt12] |
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361 show ?thesis by (simp add:readys_def wq_def s_waiting_def, auto) |
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362 qed |
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363 } moreover { |
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364 assume lt12: "t2 < t1" |
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365 let ?t3 = "Suc t1" |
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366 from lt1 have le_t3: "?t3 \<le> length s" by auto |
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367 from moment_plus [OF this] |
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368 obtain e where eq_m: "moment ?t3 s = e#moment t1 s" by auto |
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369 have lt_t3: "t1 < ?t3" by simp |
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370 from nn1 [rule_format, OF this] and eq_m |
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371 have h1: "thread \<in> set (wq (e#moment t1 s) cs1)" and |
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372 h2: "thread \<noteq> hd (wq (e#moment t1 s) cs1)" by auto |
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373 have "vt (e#moment t1 s)" |
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374 proof - |
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375 from vt_moment |
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376 have "vt (moment ?t3 s)" . |
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377 with eq_m show ?thesis by simp |
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378 qed |
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379 then interpret vt_e: valid_trace_e "moment t1 s" e |
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380 by (unfold_locales, auto, cases, auto) |
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381 have ?thesis |
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382 proof(cases "thread \<in> set (wq (moment t1 s) cs1)") |
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383 case True |
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384 from True and np1 have eq_th: "thread = hd (wq (moment t1 s) cs1)" |
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385 by auto |
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386 from vt_e.abs2 True eq_th h2 h1 |
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387 show ?thesis by auto |
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388 next |
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389 case False |
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390 from vt_e.block_pre [OF False h1] |
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391 have "e = P thread cs1" . |
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392 with vt_e.vt_e have "vt ((P thread cs1)# moment t1 s)" by simp |
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393 from p_pre [OF this] have "thread \<in> runing (moment t1 s)" by simp |
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394 with runing_ready have "thread \<in> readys (moment t1 s)" by auto |
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395 with nn2 [rule_format, OF lt12] |
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396 show ?thesis by (simp add:readys_def wq_def s_waiting_def, auto) |
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397 qed |
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398 } moreover { |
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399 assume eqt12: "t1 = t2" |
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400 let ?t3 = "Suc t1" |
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401 from lt1 have le_t3: "?t3 \<le> length s" by auto |
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402 from moment_plus [OF this] |
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403 obtain e where eq_m: "moment ?t3 s = e#moment t1 s" by auto |
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404 have lt_t3: "t1 < ?t3" by simp |
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405 from nn1 [rule_format, OF this] and eq_m |
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406 have h1: "thread \<in> set (wq (e#moment t1 s) cs1)" and |
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407 h2: "thread \<noteq> hd (wq (e#moment t1 s) cs1)" by auto |
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408 have vt_e: "vt (e#moment t1 s)" |
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409 proof - |
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410 from vt_moment |
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411 have "vt (moment ?t3 s)" . |
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412 with eq_m show ?thesis by simp |
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413 qed |
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414 then interpret vt_e: valid_trace_e "moment t1 s" e |
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415 by (unfold_locales, auto, cases, auto) |
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416 have ?thesis |
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417 proof(cases "thread \<in> set (wq (moment t1 s) cs1)") |
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418 case True |
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419 from True and np1 have eq_th: "thread = hd (wq (moment t1 s) cs1)" |
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420 by auto |
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421 from vt_e.abs2 [OF True eq_th h2 h1] |
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422 show ?thesis by auto |
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423 next |
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424 case False |
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425 from vt_e.block_pre [OF False h1] |
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426 have eq_e1: "e = P thread cs1" . |
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427 have lt_t3: "t1 < ?t3" by simp |
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428 with eqt12 have "t2 < ?t3" by simp |
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429 from nn2 [rule_format, OF this] and eq_m and eqt12 |
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430 have h1: "thread \<in> set (wq (e#moment t2 s) cs2)" and |
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431 h2: "thread \<noteq> hd (wq (e#moment t2 s) cs2)" by auto |
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432 show ?thesis |
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433 proof(cases "thread \<in> set (wq (moment t2 s) cs2)") |
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434 case True |
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435 from True and np2 have eq_th: "thread = hd (wq (moment t2 s) cs2)" |
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436 by auto |
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437 from vt_e and eqt12 have "vt (e#moment t2 s)" by simp |
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438 then interpret vt_e2: valid_trace_e "moment t2 s" e |
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439 by (unfold_locales, auto, cases, auto) |
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440 from vt_e2.abs2 [OF True eq_th h2 h1] |
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441 show ?thesis . |
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442 next |
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443 case False |
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444 have "vt (e#moment t2 s)" |
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445 proof - |
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446 from vt_moment eqt12 |
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447 have "vt (moment (Suc t2) s)" by auto |
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448 with eq_m eqt12 show ?thesis by simp |
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449 qed |
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450 then interpret vt_e2: valid_trace_e "moment t2 s" e |
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451 by (unfold_locales, auto, cases, auto) |
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452 from vt_e2.block_pre [OF False h1] |
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453 have "e = P thread cs2" . |
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454 with eq_e1 neq12 show ?thesis by auto |
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455 qed |
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456 qed |
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457 } ultimately show ?thesis by arith |
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458 qed |
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459 qed |
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460 |
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461 text {* |
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462 This lemma is a simple corrolary of @{text "waiting_unique_pre"}. |
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463 *} |
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464 |
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465 lemma waiting_unique: |
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466 assumes "waiting s th cs1" |
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467 and "waiting s th cs2" |
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468 shows "cs1 = cs2" |
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469 using waiting_unique_pre assms |
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470 unfolding wq_def s_waiting_def |
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471 by auto |
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472 |
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473 end |
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474 |
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475 (* not used *) |
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476 text {* |
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477 Every thread can only be blocked on one critical resource, |
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478 symmetrically, every critical resource can only be held by one thread. |
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479 This fact is much more easier according to our definition. |
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480 *} |
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481 lemma held_unique: |
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482 assumes "holding (s::event list) th1 cs" |
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483 and "holding s th2 cs" |
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484 shows "th1 = th2" |
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485 by (insert assms, unfold s_holding_def, auto) |
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486 |
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487 |
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488 lemma last_set_lt: "th \<in> threads s \<Longrightarrow> last_set th s < length s" |
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489 apply (induct s, auto) |
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490 by (case_tac a, auto split:if_splits) |
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491 |
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492 lemma last_set_unique: |
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493 "\<lbrakk>last_set th1 s = last_set th2 s; th1 \<in> threads s; th2 \<in> threads s\<rbrakk> |
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494 \<Longrightarrow> th1 = th2" |
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495 apply (induct s, auto) |
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496 by (case_tac a, auto split:if_splits dest:last_set_lt) |
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497 |
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498 lemma preced_unique : |
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499 assumes pcd_eq: "preced th1 s = preced th2 s" |
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500 and th_in1: "th1 \<in> threads s" |
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501 and th_in2: " th2 \<in> threads s" |
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502 shows "th1 = th2" |
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503 proof - |
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504 from pcd_eq have "last_set th1 s = last_set th2 s" by (simp add:preced_def) |
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505 from last_set_unique [OF this th_in1 th_in2] |
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506 show ?thesis . |
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507 qed |
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508 |
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509 lemma preced_linorder: |
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510 assumes neq_12: "th1 \<noteq> th2" |
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511 and th_in1: "th1 \<in> threads s" |
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512 and th_in2: " th2 \<in> threads s" |
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513 shows "preced th1 s < preced th2 s \<or> preced th1 s > preced th2 s" |
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514 proof - |
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515 from preced_unique [OF _ th_in1 th_in2] and neq_12 |
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516 have "preced th1 s \<noteq> preced th2 s" by auto |
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517 thus ?thesis by auto |
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518 qed |
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519 |
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520 (* An aux lemma used later *) |
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521 lemma unique_minus: |
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522 fixes x y z r |
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523 assumes unique: "\<And> a b c. \<lbrakk>(a, b) \<in> r; (a, c) \<in> r\<rbrakk> \<Longrightarrow> b = c" |
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524 and xy: "(x, y) \<in> r" |
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525 and xz: "(x, z) \<in> r^+" |
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526 and neq: "y \<noteq> z" |
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527 shows "(y, z) \<in> r^+" |
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528 proof - |
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529 from xz and neq show ?thesis |
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530 proof(induct) |
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531 case (base ya) |
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532 have "(x, ya) \<in> r" by fact |
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533 from unique [OF xy this] have "y = ya" . |
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534 with base show ?case by auto |
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535 next |
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536 case (step ya z) |
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537 show ?case |
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538 proof(cases "y = ya") |
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539 case True |
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540 from step True show ?thesis by simp |
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541 next |
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542 case False |
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543 from step False |
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544 show ?thesis by auto |
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545 qed |
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546 qed |
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547 qed |
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548 |
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549 lemma unique_base: |
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550 fixes r x y z |
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551 assumes unique: "\<And> a b c. \<lbrakk>(a, b) \<in> r; (a, c) \<in> r\<rbrakk> \<Longrightarrow> b = c" |
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552 and xy: "(x, y) \<in> r" |
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553 and xz: "(x, z) \<in> r^+" |
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554 and neq_yz: "y \<noteq> z" |
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555 shows "(y, z) \<in> r^+" |
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556 proof - |
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557 from xz neq_yz show ?thesis |
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558 proof(induct) |
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559 case (base ya) |
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560 from xy unique base show ?case by auto |
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561 next |
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562 case (step ya z) |
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563 show ?case |
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564 proof(cases "y = ya") |
|
565 case True |
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566 from True step show ?thesis by auto |
|
567 next |
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568 case False |
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569 from False step |
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570 have "(y, ya) \<in> r\<^sup>+" by auto |
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571 with step show ?thesis by auto |
|
572 qed |
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573 qed |
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574 qed |
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575 |
|
576 lemma unique_chain: |
|
577 fixes r x y z |
|
578 assumes unique: "\<And> a b c. \<lbrakk>(a, b) \<in> r; (a, c) \<in> r\<rbrakk> \<Longrightarrow> b = c" |
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579 and xy: "(x, y) \<in> r^+" |
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580 and xz: "(x, z) \<in> r^+" |
|
581 and neq_yz: "y \<noteq> z" |
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582 shows "(y, z) \<in> r^+ \<or> (z, y) \<in> r^+" |
|
583 proof - |
|
584 from xy xz neq_yz show ?thesis |
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585 proof(induct) |
|
586 case (base y) |
|
587 have h1: "(x, y) \<in> r" and h2: "(x, z) \<in> r\<^sup>+" and h3: "y \<noteq> z" using base by auto |
|
588 from unique_base [OF _ h1 h2 h3] and unique show ?case by auto |
|
589 next |
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590 case (step y za) |
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591 show ?case |
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592 proof(cases "y = z") |
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593 case True |
|
594 from True step show ?thesis by auto |
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595 next |
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596 case False |
|
597 from False step have "(y, z) \<in> r\<^sup>+ \<or> (z, y) \<in> r\<^sup>+" by auto |
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598 thus ?thesis |
|
599 proof |
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600 assume "(z, y) \<in> r\<^sup>+" |
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601 with step have "(z, za) \<in> r\<^sup>+" by auto |
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602 thus ?thesis by auto |
|
603 next |
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604 assume h: "(y, z) \<in> r\<^sup>+" |
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605 from step have yza: "(y, za) \<in> r" by simp |
|
606 from step have "za \<noteq> z" by simp |
|
607 from unique_minus [OF _ yza h this] and unique |
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608 have "(za, z) \<in> r\<^sup>+" by auto |
|
609 thus ?thesis by auto |
|
610 qed |
|
611 qed |
|
612 qed |
|
613 qed |
|
614 |
|
615 text {* |
|
616 The following three lemmas show that @{text "RAG"} does not change |
|
617 by the happening of @{text "Set"}, @{text "Create"} and @{text "Exit"} |
|
618 events, respectively. |
|
619 *} |
|
620 |
|
621 lemma RAG_set_unchanged: "(RAG (Set th prio # s)) = RAG s" |
|
622 apply (unfold s_RAG_def s_waiting_def wq_def) |
|
623 by (simp add:Let_def) |
|
624 |
|
625 lemma RAG_create_unchanged: "(RAG (Create th prio # s)) = RAG s" |
|
626 apply (unfold s_RAG_def s_waiting_def wq_def) |
|
627 by (simp add:Let_def) |
|
628 |
|
629 lemma RAG_exit_unchanged: "(RAG (Exit th # s)) = RAG s" |
|
630 apply (unfold s_RAG_def s_waiting_def wq_def) |
|
631 by (simp add:Let_def) |
|
632 |
|
633 |
|
634 text {* |
|
635 The following lemmas are used in the proof of |
|
636 lemma @{text "step_RAG_v"}, which characterizes how the @{text "RAG"} is changed |
|
637 by @{text "V"}-events. |
|
638 However, since our model is very concise, such seemingly obvious lemmas need to be derived from scratch, |
|
639 starting from the model definitions. |
|
640 *} |
|
641 lemma step_v_hold_inv[elim_format]: |
|
642 "\<And>c t. \<lbrakk>vt (V th cs # s); |
|
643 \<not> holding (wq s) t c; holding (wq (V th cs # s)) t c\<rbrakk> \<Longrightarrow> |
|
644 next_th s th cs t \<and> c = cs" |
|
645 proof - |
|
646 fix c t |
|
647 assume vt: "vt (V th cs # s)" |
|
648 and nhd: "\<not> holding (wq s) t c" |
|
649 and hd: "holding (wq (V th cs # s)) t c" |
|
650 show "next_th s th cs t \<and> c = cs" |
|
651 proof(cases "c = cs") |
|
652 case False |
|
653 with nhd hd show ?thesis |
|
654 by (unfold cs_holding_def wq_def, auto simp:Let_def) |
|
655 next |
|
656 case True |
|
657 with step_back_step [OF vt] |
|
658 have "step s (V th c)" by simp |
|
659 hence "next_th s th cs t" |
|
660 proof(cases) |
|
661 assume "holding s th c" |
|
662 with nhd hd show ?thesis |
|
663 apply (unfold s_holding_def cs_holding_def wq_def next_th_def, |
|
664 auto simp:Let_def split:list.splits if_splits) |
|
665 proof - |
|
666 assume " hd (SOME q. distinct q \<and> q = []) \<in> set (SOME q. distinct q \<and> q = [])" |
|
667 moreover have "\<dots> = set []" |
|
668 proof(rule someI2) |
|
669 show "distinct [] \<and> [] = []" by auto |
|
670 next |
|
671 fix x assume "distinct x \<and> x = []" |
|
672 thus "set x = set []" by auto |
|
673 qed |
|
674 ultimately show False by auto |
|
675 next |
|
676 assume " hd (SOME q. distinct q \<and> q = []) \<in> set (SOME q. distinct q \<and> q = [])" |
|
677 moreover have "\<dots> = set []" |
|
678 proof(rule someI2) |
|
679 show "distinct [] \<and> [] = []" by auto |
|
680 next |
|
681 fix x assume "distinct x \<and> x = []" |
|
682 thus "set x = set []" by auto |
|
683 qed |
|
684 ultimately show False by auto |
|
685 qed |
|
686 qed |
|
687 with True show ?thesis by auto |
|
688 qed |
|
689 qed |
|
690 |
|
691 text {* |
|
692 The following @{text "step_v_wait_inv"} is also an obvious lemma, which, however, needs to be |
|
693 derived from scratch, which confirms the correctness of the definition of @{text "next_th"}. |
|
694 *} |
|
695 lemma step_v_wait_inv[elim_format]: |
|
696 "\<And>t c. \<lbrakk>vt (V th cs # s); \<not> waiting (wq (V th cs # s)) t c; waiting (wq s) t c |
|
697 \<rbrakk> |
|
698 \<Longrightarrow> (next_th s th cs t \<and> cs = c)" |
|
699 proof - |
|
700 fix t c |
|
701 assume vt: "vt (V th cs # s)" |
|
702 and nw: "\<not> waiting (wq (V th cs # s)) t c" |
|
703 and wt: "waiting (wq s) t c" |
|
704 from vt interpret vt_v: valid_trace_e s "V th cs" |
|
705 by (cases, unfold_locales, simp) |
|
706 show "next_th s th cs t \<and> cs = c" |
|
707 proof(cases "cs = c") |
|
708 case False |
|
709 with nw wt show ?thesis |
|
710 by (auto simp:cs_waiting_def wq_def Let_def) |
|
711 next |
|
712 case True |
|
713 from nw[folded True] wt[folded True] |
|
714 have "next_th s th cs t" |
|
715 apply (unfold next_th_def, auto simp:cs_waiting_def wq_def Let_def split:list.splits) |
|
716 proof - |
|
717 fix a list |
|
718 assume t_in: "t \<in> set list" |
|
719 and t_ni: "t \<notin> set (SOME q. distinct q \<and> set q = set list)" |
|
720 and eq_wq: "wq_fun (schs s) cs = a # list" |
|
721 have " set (SOME q. distinct q \<and> set q = set list) = set list" |
|
722 proof(rule someI2) |
|
723 from vt_v.wq_distinct[of cs] and eq_wq[folded wq_def] |
|
724 show "distinct list \<and> set list = set list" by auto |
|
725 next |
|
726 show "\<And>x. distinct x \<and> set x = set list \<Longrightarrow> set x = set list" |
|
727 by auto |
|
728 qed |
|
729 with t_ni and t_in show "a = th" by auto |
|
730 next |
|
731 fix a list |
|
732 assume t_in: "t \<in> set list" |
|
733 and t_ni: "t \<notin> set (SOME q. distinct q \<and> set q = set list)" |
|
734 and eq_wq: "wq_fun (schs s) cs = a # list" |
|
735 have " set (SOME q. distinct q \<and> set q = set list) = set list" |
|
736 proof(rule someI2) |
|
737 from vt_v.wq_distinct[of cs] and eq_wq[folded wq_def] |
|
738 show "distinct list \<and> set list = set list" by auto |
|
739 next |
|
740 show "\<And>x. distinct x \<and> set x = set list \<Longrightarrow> set x = set list" |
|
741 by auto |
|
742 qed |
|
743 with t_ni and t_in show "t = hd (SOME q. distinct q \<and> set q = set list)" by auto |
|
744 next |
|
745 fix a list |
|
746 assume eq_wq: "wq_fun (schs s) cs = a # list" |
|
747 from step_back_step[OF vt] |
|
748 show "a = th" |
|
749 proof(cases) |
|
750 assume "holding s th cs" |
|
751 with eq_wq show ?thesis |
|
752 by (unfold s_holding_def wq_def, auto) |
|
753 qed |
|
754 qed |
|
755 with True show ?thesis by simp |
|
756 qed |
|
757 qed |
|
758 |
|
759 lemma step_v_not_wait[consumes 3]: |
|
760 "\<lbrakk>vt (V th cs # s); next_th s th cs t; waiting (wq (V th cs # s)) t cs\<rbrakk> \<Longrightarrow> False" |
|
761 by (unfold next_th_def cs_waiting_def wq_def, auto simp:Let_def) |
|
762 |
|
763 lemma step_v_release: |
|
764 "\<lbrakk>vt (V th cs # s); holding (wq (V th cs # s)) th cs\<rbrakk> \<Longrightarrow> False" |
|
765 proof - |
|
766 assume vt: "vt (V th cs # s)" |
|
767 and hd: "holding (wq (V th cs # s)) th cs" |
|
768 from vt interpret vt_v: valid_trace_e s "V th cs" |
|
769 by (cases, unfold_locales, simp+) |
|
770 from step_back_step [OF vt] and hd |
|
771 show "False" |
|
772 proof(cases) |
|
773 assume "holding (wq (V th cs # s)) th cs" and "holding s th cs" |
|
774 thus ?thesis |
|
775 apply (unfold s_holding_def wq_def cs_holding_def) |
|
776 apply (auto simp:Let_def split:list.splits) |
|
777 proof - |
|
778 fix list |
|
779 assume eq_wq[folded wq_def]: |
|
780 "wq_fun (schs s) cs = hd (SOME q. distinct q \<and> set q = set list) # list" |
|
781 and hd_in: "hd (SOME q. distinct q \<and> set q = set list) |
|
782 \<in> set (SOME q. distinct q \<and> set q = set list)" |
|
783 have "set (SOME q. distinct q \<and> set q = set list) = set list" |
|
784 proof(rule someI2) |
|
785 from vt_v.wq_distinct[of cs] and eq_wq |
|
786 show "distinct list \<and> set list = set list" by auto |
|
787 next |
|
788 show "\<And>x. distinct x \<and> set x = set list \<Longrightarrow> set x = set list" |
|
789 by auto |
|
790 qed |
|
791 moreover have "distinct (hd (SOME q. distinct q \<and> set q = set list) # list)" |
|
792 proof - |
|
793 from vt_v.wq_distinct[of cs] and eq_wq |
|
794 show ?thesis by auto |
|
795 qed |
|
796 moreover note eq_wq and hd_in |
|
797 ultimately show "False" by auto |
|
798 qed |
|
799 qed |
|
800 qed |
|
801 |
|
802 lemma step_v_get_hold: |
|
803 "\<And>th'. \<lbrakk>vt (V th cs # s); \<not> holding (wq (V th cs # s)) th' cs; next_th s th cs th'\<rbrakk> \<Longrightarrow> False" |
|
804 apply (unfold cs_holding_def next_th_def wq_def, |
|
805 auto simp:Let_def) |
|
806 proof - |
|
807 fix rest |
|
808 assume vt: "vt (V th cs # s)" |
|
809 and eq_wq[folded wq_def]: " wq_fun (schs s) cs = th # rest" |
|
810 and nrest: "rest \<noteq> []" |
|
811 and ni: "hd (SOME q. distinct q \<and> set q = set rest) |
|
812 \<notin> set (SOME q. distinct q \<and> set q = set rest)" |
|
813 from vt interpret vt_v: valid_trace_e s "V th cs" |
|
814 by (cases, unfold_locales, simp+) |
|
815 have "(SOME q. distinct q \<and> set q = set rest) \<noteq> []" |
|
816 proof(rule someI2) |
|
817 from vt_v.wq_distinct[of cs] and eq_wq |
|
818 show "distinct rest \<and> set rest = set rest" by auto |
|
819 next |
|
820 fix x assume "distinct x \<and> set x = set rest" |
|
821 hence "set x = set rest" by auto |
|
822 with nrest |
|
823 show "x \<noteq> []" by (case_tac x, auto) |
|
824 qed |
|
825 with ni show "False" by auto |
|
826 qed |
|
827 |
|
828 lemma step_v_release_inv[elim_format]: |
|
829 "\<And>c t. \<lbrakk>vt (V th cs # s); \<not> holding (wq (V th cs # s)) t c; holding (wq s) t c\<rbrakk> \<Longrightarrow> |
|
830 c = cs \<and> t = th" |
|
831 apply (unfold cs_holding_def wq_def, auto simp:Let_def split:if_splits list.splits) |
|
832 proof - |
|
833 fix a list |
|
834 assume vt: "vt (V th cs # s)" and eq_wq: "wq_fun (schs s) cs = a # list" |
|
835 from step_back_step [OF vt] show "a = th" |
|
836 proof(cases) |
|
837 assume "holding s th cs" with eq_wq |
|
838 show ?thesis |
|
839 by (unfold s_holding_def wq_def, auto) |
|
840 qed |
|
841 next |
|
842 fix a list |
|
843 assume vt: "vt (V th cs # s)" and eq_wq: "wq_fun (schs s) cs = a # list" |
|
844 from step_back_step [OF vt] show "a = th" |
|
845 proof(cases) |
|
846 assume "holding s th cs" with eq_wq |
|
847 show ?thesis |
|
848 by (unfold s_holding_def wq_def, auto) |
|
849 qed |
|
850 qed |
|
851 |
|
852 lemma step_v_waiting_mono: |
|
853 "\<And>t c. \<lbrakk>vt (V th cs # s); waiting (wq (V th cs # s)) t c\<rbrakk> \<Longrightarrow> waiting (wq s) t c" |
|
854 proof - |
|
855 fix t c |
|
856 let ?s' = "(V th cs # s)" |
|
857 assume vt: "vt ?s'" |
|
858 and wt: "waiting (wq ?s') t c" |
|
859 from vt interpret vt_v: valid_trace_e s "V th cs" |
|
860 by (cases, unfold_locales, simp+) |
|
861 show "waiting (wq s) t c" |
|
862 proof(cases "c = cs") |
|
863 case False |
|
864 assume neq_cs: "c \<noteq> cs" |
|
865 hence "waiting (wq ?s') t c = waiting (wq s) t c" |
|
866 by (unfold cs_waiting_def wq_def, auto simp:Let_def) |
|
867 with wt show ?thesis by simp |
|
868 next |
|
869 case True |
|
870 with wt show ?thesis |
|
871 apply (unfold cs_waiting_def wq_def, auto simp:Let_def split:list.splits) |
|
872 proof - |
|
873 fix a list |
|
874 assume not_in: "t \<notin> set list" |
|
875 and is_in: "t \<in> set (SOME q. distinct q \<and> set q = set list)" |
|
876 and eq_wq: "wq_fun (schs s) cs = a # list" |
|
877 have "set (SOME q. distinct q \<and> set q = set list) = set list" |
|
878 proof(rule someI2) |
|
879 from vt_v.wq_distinct [of cs] |
|
880 and eq_wq[folded wq_def] |
|
881 show "distinct list \<and> set list = set list" by auto |
|
882 next |
|
883 fix x assume "distinct x \<and> set x = set list" |
|
884 thus "set x = set list" by auto |
|
885 qed |
|
886 with not_in is_in show "t = a" by auto |
|
887 next |
|
888 fix list |
|
889 assume is_waiting: "waiting (wq (V th cs # s)) t cs" |
|
890 and eq_wq: "wq_fun (schs s) cs = t # list" |
|
891 hence "t \<in> set list" |
|
892 apply (unfold wq_def, auto simp:Let_def cs_waiting_def) |
|
893 proof - |
|
894 assume " t \<in> set (SOME q. distinct q \<and> set q = set list)" |
|
895 moreover have "\<dots> = set list" |
|
896 proof(rule someI2) |
|
897 from vt_v.wq_distinct [of cs] |
|
898 and eq_wq[folded wq_def] |
|
899 show "distinct list \<and> set list = set list" by auto |
|
900 next |
|
901 fix x assume "distinct x \<and> set x = set list" |
|
902 thus "set x = set list" by auto |
|
903 qed |
|
904 ultimately show "t \<in> set list" by simp |
|
905 qed |
|
906 with eq_wq and vt_v.wq_distinct [of cs, unfolded wq_def] |
|
907 show False by auto |
|
908 qed |
|
909 qed |
|
910 qed |
|
911 |
|
912 text {* (* ddd *) |
|
913 The following @{text "step_RAG_v"} lemma charaterizes how @{text "RAG"} is changed |
|
914 with the happening of @{text "V"}-events: |
|
915 *} |
|
916 lemma step_RAG_v: |
|
917 fixes th::thread |
|
918 assumes vt: |
|
919 "vt (V th cs#s)" |
|
920 shows " |
|
921 RAG (V th cs # s) = |
|
922 RAG s - {(Cs cs, Th th)} - |
|
923 {(Th th', Cs cs) |th'. next_th s th cs th'} \<union> |
|
924 {(Cs cs, Th th') |th'. next_th s th cs th'}" |
|
925 apply (insert vt, unfold s_RAG_def) |
|
926 apply (auto split:if_splits list.splits simp:Let_def) |
|
927 apply (auto elim: step_v_waiting_mono step_v_hold_inv |
|
928 step_v_release step_v_wait_inv |
|
929 step_v_get_hold step_v_release_inv) |
|
930 apply (erule_tac step_v_not_wait, auto) |
|
931 done |
|
932 |
|
933 text {* |
|
934 The following @{text "step_RAG_p"} lemma charaterizes how @{text "RAG"} is changed |
|
935 with the happening of @{text "P"}-events: |
|
936 *} |
|
937 lemma step_RAG_p: |
|
938 "vt (P th cs#s) \<Longrightarrow> |
|
939 RAG (P th cs # s) = (if (wq s cs = []) then RAG s \<union> {(Cs cs, Th th)} |
|
940 else RAG s \<union> {(Th th, Cs cs)})" |
|
941 apply(simp only: s_RAG_def wq_def) |
|
942 apply (auto split:list.splits prod.splits simp:Let_def wq_def cs_waiting_def cs_holding_def) |
|
943 apply(case_tac "csa = cs", auto) |
|
944 apply(fold wq_def) |
|
945 apply(drule_tac step_back_step) |
|
946 apply(ind_cases " step s (P (hd (wq s cs)) cs)") |
|
947 apply(simp add:s_RAG_def wq_def cs_holding_def) |
|
948 apply(auto) |
|
949 done |
|
950 |
|
951 |
|
952 lemma RAG_target_th: "(Th th, x) \<in> RAG (s::state) \<Longrightarrow> \<exists> cs. x = Cs cs" |
|
953 by (unfold s_RAG_def, auto) |
|
954 |
|
955 context valid_trace |
|
956 begin |
|
957 |
|
958 text {* |
|
959 The following lemma shows that @{text "RAG"} is acyclic. |
|
960 The overall structure is by induction on the formation of @{text "vt s"} |
|
961 and then case analysis on event @{text "e"}, where the non-trivial cases |
|
962 for those for @{text "V"} and @{text "P"} events. |
|
963 *} |
|
964 lemma acyclic_RAG: |
|
965 shows "acyclic (RAG s)" |
|
966 using vt |
|
967 proof(induct) |
|
968 case (vt_cons s e) |
|
969 interpret vt_s: valid_trace s using vt_cons(1) |
|
970 by (unfold_locales, simp) |
|
971 assume ih: "acyclic (RAG s)" |
|
972 and stp: "step s e" |
|
973 and vt: "vt s" |
|
974 show ?case |
|
975 proof(cases e) |
|
976 case (Create th prio) |
|
977 with ih |
|
978 show ?thesis by (simp add:RAG_create_unchanged) |
|
979 next |
|
980 case (Exit th) |
|
981 with ih show ?thesis by (simp add:RAG_exit_unchanged) |
|
982 next |
|
983 case (V th cs) |
|
984 from V vt stp have vtt: "vt (V th cs#s)" by auto |
|
985 from step_RAG_v [OF this] |
|
986 have eq_de: |
|
987 "RAG (e # s) = |
|
988 RAG s - {(Cs cs, Th th)} - {(Th th', Cs cs) |th'. next_th s th cs th'} \<union> |
|
989 {(Cs cs, Th th') |th'. next_th s th cs th'}" |
|
990 (is "?L = (?A - ?B - ?C) \<union> ?D") by (simp add:V) |
|
991 from ih have ac: "acyclic (?A - ?B - ?C)" by (auto elim:acyclic_subset) |
|
992 from step_back_step [OF vtt] |
|
993 have "step s (V th cs)" . |
|
994 thus ?thesis |
|
995 proof(cases) |
|
996 assume "holding s th cs" |
|
997 hence th_in: "th \<in> set (wq s cs)" and |
|
998 eq_hd: "th = hd (wq s cs)" unfolding s_holding_def wq_def by auto |
|
999 then obtain rest where |
|
1000 eq_wq: "wq s cs = th#rest" |
|
1001 by (cases "wq s cs", auto) |
|
1002 show ?thesis |
|
1003 proof(cases "rest = []") |
|
1004 case False |
|
1005 let ?th' = "hd (SOME q. distinct q \<and> set q = set rest)" |
|
1006 from eq_wq False have eq_D: "?D = {(Cs cs, Th ?th')}" |
|
1007 by (unfold next_th_def, auto) |
|
1008 let ?E = "(?A - ?B - ?C)" |
|
1009 have "(Th ?th', Cs cs) \<notin> ?E\<^sup>*" |
|
1010 proof |
|
1011 assume "(Th ?th', Cs cs) \<in> ?E\<^sup>*" |
|
1012 hence " (Th ?th', Cs cs) \<in> ?E\<^sup>+" by (simp add: rtrancl_eq_or_trancl) |
|
1013 from tranclD [OF this] |
|
1014 obtain x where th'_e: "(Th ?th', x) \<in> ?E" by blast |
|
1015 hence th_d: "(Th ?th', x) \<in> ?A" by simp |
|
1016 from RAG_target_th [OF this] |
|
1017 obtain cs' where eq_x: "x = Cs cs'" by auto |
|
1018 with th_d have "(Th ?th', Cs cs') \<in> ?A" by simp |
|
1019 hence wt_th': "waiting s ?th' cs'" |
|
1020 unfolding s_RAG_def s_waiting_def cs_waiting_def wq_def by simp |
|
1021 hence "cs' = cs" |
|
1022 proof(rule vt_s.waiting_unique) |
|
1023 from eq_wq vt_s.wq_distinct[of cs] |
|
1024 show "waiting s ?th' cs" |
|
1025 apply (unfold s_waiting_def wq_def, auto) |
|
1026 proof - |
|
1027 assume hd_in: "hd (SOME q. distinct q \<and> set q = set rest) \<notin> set rest" |
|
1028 and eq_wq: "wq_fun (schs s) cs = th # rest" |
|
1029 have "(SOME q. distinct q \<and> set q = set rest) \<noteq> []" |
|
1030 proof(rule someI2) |
|
1031 from vt_s.wq_distinct[of cs] and eq_wq |
|
1032 show "distinct rest \<and> set rest = set rest" unfolding wq_def by auto |
|
1033 next |
|
1034 fix x assume "distinct x \<and> set x = set rest" |
|
1035 with False show "x \<noteq> []" by auto |
|
1036 qed |
|
1037 hence "hd (SOME q. distinct q \<and> set q = set rest) \<in> |
|
1038 set (SOME q. distinct q \<and> set q = set rest)" by auto |
|
1039 moreover have "\<dots> = set rest" |
|
1040 proof(rule someI2) |
|
1041 from vt_s.wq_distinct[of cs] and eq_wq |
|
1042 show "distinct rest \<and> set rest = set rest" unfolding wq_def by auto |
|
1043 next |
|
1044 show "\<And>x. distinct x \<and> set x = set rest \<Longrightarrow> set x = set rest" by auto |
|
1045 qed |
|
1046 moreover note hd_in |
|
1047 ultimately show "hd (SOME q. distinct q \<and> set q = set rest) = th" by auto |
|
1048 next |
|
1049 assume hd_in: "hd (SOME q. distinct q \<and> set q = set rest) \<notin> set rest" |
|
1050 and eq_wq: "wq s cs = hd (SOME q. distinct q \<and> set q = set rest) # rest" |
|
1051 have "(SOME q. distinct q \<and> set q = set rest) \<noteq> []" |
|
1052 proof(rule someI2) |
|
1053 from vt_s.wq_distinct[of cs] and eq_wq |
|
1054 show "distinct rest \<and> set rest = set rest" by auto |
|
1055 next |
|
1056 fix x assume "distinct x \<and> set x = set rest" |
|
1057 with False show "x \<noteq> []" by auto |
|
1058 qed |
|
1059 hence "hd (SOME q. distinct q \<and> set q = set rest) \<in> |
|
1060 set (SOME q. distinct q \<and> set q = set rest)" by auto |
|
1061 moreover have "\<dots> = set rest" |
|
1062 proof(rule someI2) |
|
1063 from vt_s.wq_distinct[of cs] and eq_wq |
|
1064 show "distinct rest \<and> set rest = set rest" by auto |
|
1065 next |
|
1066 show "\<And>x. distinct x \<and> set x = set rest \<Longrightarrow> set x = set rest" by auto |
|
1067 qed |
|
1068 moreover note hd_in |
|
1069 ultimately show False by auto |
|
1070 qed |
|
1071 qed |
|
1072 with th'_e eq_x have "(Th ?th', Cs cs) \<in> ?E" by simp |
|
1073 with False |
|
1074 show "False" by (auto simp: next_th_def eq_wq) |
|
1075 qed |
|
1076 with acyclic_insert[symmetric] and ac |
|
1077 and eq_de eq_D show ?thesis by auto |
|
1078 next |
|
1079 case True |
|
1080 with eq_wq |
|
1081 have eq_D: "?D = {}" |
|
1082 by (unfold next_th_def, auto) |
|
1083 with eq_de ac |
|
1084 show ?thesis by auto |
|
1085 qed |
|
1086 qed |
|
1087 next |
|
1088 case (P th cs) |
|
1089 from P vt stp have vtt: "vt (P th cs#s)" by auto |
|
1090 from step_RAG_p [OF this] P |
|
1091 have "RAG (e # s) = |
|
1092 (if wq s cs = [] then RAG s \<union> {(Cs cs, Th th)} else |
|
1093 RAG s \<union> {(Th th, Cs cs)})" (is "?L = ?R") |
|
1094 by simp |
|
1095 moreover have "acyclic ?R" |
|
1096 proof(cases "wq s cs = []") |
|
1097 case True |
|
1098 hence eq_r: "?R = RAG s \<union> {(Cs cs, Th th)}" by simp |
|
1099 have "(Th th, Cs cs) \<notin> (RAG s)\<^sup>*" |
|
1100 proof |
|
1101 assume "(Th th, Cs cs) \<in> (RAG s)\<^sup>*" |
|
1102 hence "(Th th, Cs cs) \<in> (RAG s)\<^sup>+" by (simp add: rtrancl_eq_or_trancl) |
|
1103 from tranclD2 [OF this] |
|
1104 obtain x where "(x, Cs cs) \<in> RAG s" by auto |
|
1105 with True show False by (auto simp:s_RAG_def cs_waiting_def) |
|
1106 qed |
|
1107 with acyclic_insert ih eq_r show ?thesis by auto |
|
1108 next |
|
1109 case False |
|
1110 hence eq_r: "?R = RAG s \<union> {(Th th, Cs cs)}" by simp |
|
1111 have "(Cs cs, Th th) \<notin> (RAG s)\<^sup>*" |
|
1112 proof |
|
1113 assume "(Cs cs, Th th) \<in> (RAG s)\<^sup>*" |
|
1114 hence "(Cs cs, Th th) \<in> (RAG s)\<^sup>+" by (simp add: rtrancl_eq_or_trancl) |
|
1115 moreover from step_back_step [OF vtt] have "step s (P th cs)" . |
|
1116 ultimately show False |
|
1117 proof - |
|
1118 show " \<lbrakk>(Cs cs, Th th) \<in> (RAG s)\<^sup>+; step s (P th cs)\<rbrakk> \<Longrightarrow> False" |
|
1119 by (ind_cases "step s (P th cs)", simp) |
|
1120 qed |
|
1121 qed |
|
1122 with acyclic_insert ih eq_r show ?thesis by auto |
|
1123 qed |
|
1124 ultimately show ?thesis by simp |
|
1125 next |
|
1126 case (Set thread prio) |
|
1127 with ih |
|
1128 thm RAG_set_unchanged |
|
1129 show ?thesis by (simp add:RAG_set_unchanged) |
|
1130 qed |
|
1131 next |
|
1132 case vt_nil |
|
1133 show "acyclic (RAG ([]::state))" |
|
1134 by (auto simp: s_RAG_def cs_waiting_def |
|
1135 cs_holding_def wq_def acyclic_def) |
|
1136 qed |
|
1137 |
|
1138 |
|
1139 lemma finite_RAG: |
|
1140 shows "finite (RAG s)" |
|
1141 proof - |
|
1142 from vt show ?thesis |
|
1143 proof(induct) |
|
1144 case (vt_cons s e) |
|
1145 interpret vt_s: valid_trace s using vt_cons(1) |
|
1146 by (unfold_locales, simp) |
|
1147 assume ih: "finite (RAG s)" |
|
1148 and stp: "step s e" |
|
1149 and vt: "vt s" |
|
1150 show ?case |
|
1151 proof(cases e) |
|
1152 case (Create th prio) |
|
1153 with ih |
|
1154 show ?thesis by (simp add:RAG_create_unchanged) |
|
1155 next |
|
1156 case (Exit th) |
|
1157 with ih show ?thesis by (simp add:RAG_exit_unchanged) |
|
1158 next |
|
1159 case (V th cs) |
|
1160 from V vt stp have vtt: "vt (V th cs#s)" by auto |
|
1161 from step_RAG_v [OF this] |
|
1162 have eq_de: "RAG (e # s) = |
|
1163 RAG s - {(Cs cs, Th th)} - {(Th th', Cs cs) |th'. next_th s th cs th'} \<union> |
|
1164 {(Cs cs, Th th') |th'. next_th s th cs th'} |
|
1165 " |
|
1166 (is "?L = (?A - ?B - ?C) \<union> ?D") by (simp add:V) |
|
1167 moreover from ih have ac: "finite (?A - ?B - ?C)" by simp |
|
1168 moreover have "finite ?D" |
|
1169 proof - |
|
1170 have "?D = {} \<or> (\<exists> a. ?D = {a})" |
|
1171 by (unfold next_th_def, auto) |
|
1172 thus ?thesis |
|
1173 proof |
|
1174 assume h: "?D = {}" |
|
1175 show ?thesis by (unfold h, simp) |
|
1176 next |
|
1177 assume "\<exists> a. ?D = {a}" |
|
1178 thus ?thesis |
|
1179 by (metis finite.simps) |
|
1180 qed |
|
1181 qed |
|
1182 ultimately show ?thesis by simp |
|
1183 next |
|
1184 case (P th cs) |
|
1185 from P vt stp have vtt: "vt (P th cs#s)" by auto |
|
1186 from step_RAG_p [OF this] P |
|
1187 have "RAG (e # s) = |
|
1188 (if wq s cs = [] then RAG s \<union> {(Cs cs, Th th)} else |
|
1189 RAG s \<union> {(Th th, Cs cs)})" (is "?L = ?R") |
|
1190 by simp |
|
1191 moreover have "finite ?R" |
|
1192 proof(cases "wq s cs = []") |
|
1193 case True |
|
1194 hence eq_r: "?R = RAG s \<union> {(Cs cs, Th th)}" by simp |
|
1195 with True and ih show ?thesis by auto |
|
1196 next |
|
1197 case False |
|
1198 hence "?R = RAG s \<union> {(Th th, Cs cs)}" by simp |
|
1199 with False and ih show ?thesis by auto |
|
1200 qed |
|
1201 ultimately show ?thesis by auto |
|
1202 next |
|
1203 case (Set thread prio) |
|
1204 with ih |
|
1205 show ?thesis by (simp add:RAG_set_unchanged) |
|
1206 qed |
|
1207 next |
|
1208 case vt_nil |
|
1209 show "finite (RAG ([]::state))" |
|
1210 by (auto simp: s_RAG_def cs_waiting_def |
|
1211 cs_holding_def wq_def acyclic_def) |
|
1212 qed |
|
1213 qed |
|
1214 |
|
1215 text {* Several useful lemmas *} |
|
1216 |
|
1217 lemma wf_dep_converse: |
|
1218 shows "wf ((RAG s)^-1)" |
|
1219 proof(rule finite_acyclic_wf_converse) |
|
1220 from finite_RAG |
|
1221 show "finite (RAG s)" . |
|
1222 next |
|
1223 from acyclic_RAG |
|
1224 show "acyclic (RAG s)" . |
|
1225 qed |
|
1226 |
|
1227 end |
|
1228 |
|
1229 lemma hd_np_in: "x \<in> set l \<Longrightarrow> hd l \<in> set l" |
|
1230 by (induct l, auto) |
|
1231 |
|
1232 lemma th_chasing: "(Th th, Cs cs) \<in> RAG (s::state) \<Longrightarrow> \<exists> th'. (Cs cs, Th th') \<in> RAG s" |
|
1233 by (auto simp:s_RAG_def s_holding_def cs_holding_def cs_waiting_def wq_def dest:hd_np_in) |
|
1234 |
|
1235 context valid_trace |
|
1236 begin |
|
1237 |
|
1238 lemma wq_threads: |
|
1239 assumes h: "th \<in> set (wq s cs)" |
|
1240 shows "th \<in> threads s" |
|
1241 proof - |
|
1242 from vt and h show ?thesis |
|
1243 proof(induct arbitrary: th cs) |
|
1244 case (vt_cons s e) |
|
1245 interpret vt_s: valid_trace s |
|
1246 using vt_cons(1) by (unfold_locales, auto) |
|
1247 assume ih: "\<And>th cs. th \<in> set (wq s cs) \<Longrightarrow> th \<in> threads s" |
|
1248 and stp: "step s e" |
|
1249 and vt: "vt s" |
|
1250 and h: "th \<in> set (wq (e # s) cs)" |
|
1251 show ?case |
|
1252 proof(cases e) |
|
1253 case (Create th' prio) |
|
1254 with ih h show ?thesis |
|
1255 by (auto simp:wq_def Let_def) |
|
1256 next |
|
1257 case (Exit th') |
|
1258 with stp ih h show ?thesis |
|
1259 apply (auto simp:wq_def Let_def) |
|
1260 apply (ind_cases "step s (Exit th')") |
|
1261 apply (auto simp:runing_def readys_def s_holding_def s_waiting_def holdents_def |
|
1262 s_RAG_def s_holding_def cs_holding_def) |
|
1263 done |
|
1264 next |
|
1265 case (V th' cs') |
|
1266 show ?thesis |
|
1267 proof(cases "cs' = cs") |
|
1268 case False |
|
1269 with h |
|
1270 show ?thesis |
|
1271 apply(unfold wq_def V, auto simp:Let_def V split:prod.splits, fold wq_def) |
|
1272 by (drule_tac ih, simp) |
|
1273 next |
|
1274 case True |
|
1275 from h |
|
1276 show ?thesis |
|
1277 proof(unfold V wq_def) |
|
1278 assume th_in: "th \<in> set (wq_fun (schs (V th' cs' # s)) cs)" (is "th \<in> set ?l") |
|
1279 show "th \<in> threads (V th' cs' # s)" |
|
1280 proof(cases "cs = cs'") |
|
1281 case False |
|
1282 hence "?l = wq_fun (schs s) cs" by (simp add:Let_def) |
|
1283 with th_in have " th \<in> set (wq s cs)" |
|
1284 by (fold wq_def, simp) |
|
1285 from ih [OF this] show ?thesis by simp |
|
1286 next |
|
1287 case True |
|
1288 show ?thesis |
|
1289 proof(cases "wq_fun (schs s) cs'") |
|
1290 case Nil |
|
1291 with h V show ?thesis |
|
1292 apply (auto simp:wq_def Let_def split:if_splits) |
|
1293 by (fold wq_def, drule_tac ih, simp) |
|
1294 next |
|
1295 case (Cons a rest) |
|
1296 assume eq_wq: "wq_fun (schs s) cs' = a # rest" |
|
1297 with h V show ?thesis |
|
1298 apply (auto simp:Let_def wq_def split:if_splits) |
|
1299 proof - |
|
1300 assume th_in: "th \<in> set (SOME q. distinct q \<and> set q = set rest)" |
|
1301 have "set (SOME q. distinct q \<and> set q = set rest) = set rest" |
|
1302 proof(rule someI2) |
|
1303 from vt_s.wq_distinct[of cs'] and eq_wq[folded wq_def] |
|
1304 show "distinct rest \<and> set rest = set rest" by auto |
|
1305 next |
|
1306 show "\<And>x. distinct x \<and> set x = set rest \<Longrightarrow> set x = set rest" |
|
1307 by auto |
|
1308 qed |
|
1309 with eq_wq th_in have "th \<in> set (wq_fun (schs s) cs')" by auto |
|
1310 from ih[OF this[folded wq_def]] show "th \<in> threads s" . |
|
1311 next |
|
1312 assume th_in: "th \<in> set (wq_fun (schs s) cs)" |
|
1313 from ih[OF this[folded wq_def]] |
|
1314 show "th \<in> threads s" . |
|
1315 qed |
|
1316 qed |
|
1317 qed |
|
1318 qed |
|
1319 qed |
|
1320 next |
|
1321 case (P th' cs') |
|
1322 from h stp |
|
1323 show ?thesis |
|
1324 apply (unfold P wq_def) |
|
1325 apply (auto simp:Let_def split:if_splits, fold wq_def) |
|
1326 apply (auto intro:ih) |
|
1327 apply(ind_cases "step s (P th' cs')") |
|
1328 by (unfold runing_def readys_def, auto) |
|
1329 next |
|
1330 case (Set thread prio) |
|
1331 with ih h show ?thesis |
|
1332 by (auto simp:wq_def Let_def) |
|
1333 qed |
|
1334 next |
|
1335 case vt_nil |
|
1336 thus ?case by (auto simp:wq_def) |
|
1337 qed |
|
1338 qed |
|
1339 |
|
1340 lemma range_in: "\<lbrakk>(Th th) \<in> Range (RAG (s::state))\<rbrakk> \<Longrightarrow> th \<in> threads s" |
|
1341 apply(unfold s_RAG_def cs_waiting_def cs_holding_def) |
|
1342 by (auto intro:wq_threads) |
|
1343 |
|
1344 lemma readys_v_eq: |
|
1345 fixes th thread cs rest |
|
1346 assumes neq_th: "th \<noteq> thread" |
|
1347 and eq_wq: "wq s cs = thread#rest" |
|
1348 and not_in: "th \<notin> set rest" |
|
1349 shows "(th \<in> readys (V thread cs#s)) = (th \<in> readys s)" |
|
1350 proof - |
|
1351 from assms show ?thesis |
|
1352 apply (auto simp:readys_def) |
|
1353 apply(simp add:s_waiting_def[folded wq_def]) |
|
1354 apply (erule_tac x = csa in allE) |
|
1355 apply (simp add:s_waiting_def wq_def Let_def split:if_splits) |
|
1356 apply (case_tac "csa = cs", simp) |
|
1357 apply (erule_tac x = cs in allE) |
|
1358 apply(auto simp add: s_waiting_def[folded wq_def] Let_def split: list.splits) |
|
1359 apply(auto simp add: wq_def) |
|
1360 apply (auto simp:s_waiting_def wq_def Let_def split:list.splits) |
|
1361 proof - |
|
1362 assume th_nin: "th \<notin> set rest" |
|
1363 and th_in: "th \<in> set (SOME q. distinct q \<and> set q = set rest)" |
|
1364 and eq_wq: "wq_fun (schs s) cs = thread # rest" |
|
1365 have "set (SOME q. distinct q \<and> set q = set rest) = set rest" |
|
1366 proof(rule someI2) |
|
1367 from wq_distinct[of cs, unfolded wq_def] and eq_wq[unfolded wq_def] |
|
1368 show "distinct rest \<and> set rest = set rest" by auto |
|
1369 next |
|
1370 show "\<And>x. distinct x \<and> set x = set rest \<Longrightarrow> set x = set rest" by auto |
|
1371 qed |
|
1372 with th_nin th_in show False by auto |
|
1373 qed |
|
1374 qed |
|
1375 |
|
1376 text {* \noindent |
|
1377 The following lemmas shows that: starting from any node in @{text "RAG"}, |
|
1378 by chasing out-going edges, it is always possible to reach a node representing a ready |
|
1379 thread. In this lemma, it is the @{text "th'"}. |
|
1380 *} |
|
1381 |
|
1382 lemma chain_building: |
|
1383 shows "node \<in> Domain (RAG s) \<longrightarrow> (\<exists> th'. th' \<in> readys s \<and> (node, Th th') \<in> (RAG s)^+)" |
|
1384 proof - |
|
1385 from wf_dep_converse |
|
1386 have h: "wf ((RAG s)\<inverse>)" . |
|
1387 show ?thesis |
|
1388 proof(induct rule:wf_induct [OF h]) |
|
1389 fix x |
|
1390 assume ih [rule_format]: |
|
1391 "\<forall>y. (y, x) \<in> (RAG s)\<inverse> \<longrightarrow> |
|
1392 y \<in> Domain (RAG s) \<longrightarrow> (\<exists>th'. th' \<in> readys s \<and> (y, Th th') \<in> (RAG s)\<^sup>+)" |
|
1393 show "x \<in> Domain (RAG s) \<longrightarrow> (\<exists>th'. th' \<in> readys s \<and> (x, Th th') \<in> (RAG s)\<^sup>+)" |
|
1394 proof |
|
1395 assume x_d: "x \<in> Domain (RAG s)" |
|
1396 show "\<exists>th'. th' \<in> readys s \<and> (x, Th th') \<in> (RAG s)\<^sup>+" |
|
1397 proof(cases x) |
|
1398 case (Th th) |
|
1399 from x_d Th obtain cs where x_in: "(Th th, Cs cs) \<in> RAG s" by (auto simp:s_RAG_def) |
|
1400 with Th have x_in_r: "(Cs cs, x) \<in> (RAG s)^-1" by simp |
|
1401 from th_chasing [OF x_in] obtain th' where "(Cs cs, Th th') \<in> RAG s" by blast |
|
1402 hence "Cs cs \<in> Domain (RAG s)" by auto |
|
1403 from ih [OF x_in_r this] obtain th' |
|
1404 where th'_ready: " th' \<in> readys s" and cs_in: "(Cs cs, Th th') \<in> (RAG s)\<^sup>+" by auto |
|
1405 have "(x, Th th') \<in> (RAG s)\<^sup>+" using Th x_in cs_in by auto |
|
1406 with th'_ready show ?thesis by auto |
|
1407 next |
|
1408 case (Cs cs) |
|
1409 from x_d Cs obtain th' where th'_d: "(Th th', x) \<in> (RAG s)^-1" by (auto simp:s_RAG_def) |
|
1410 show ?thesis |
|
1411 proof(cases "th' \<in> readys s") |
|
1412 case True |
|
1413 from True and th'_d show ?thesis by auto |
|
1414 next |
|
1415 case False |
|
1416 from th'_d and range_in have "th' \<in> threads s" by auto |
|
1417 with False have "Th th' \<in> Domain (RAG s)" |
|
1418 by (auto simp:readys_def wq_def s_waiting_def s_RAG_def cs_waiting_def Domain_def) |
|
1419 from ih [OF th'_d this] |
|
1420 obtain th'' where |
|
1421 th''_r: "th'' \<in> readys s" and |
|
1422 th''_in: "(Th th', Th th'') \<in> (RAG s)\<^sup>+" by auto |
|
1423 from th'_d and th''_in |
|
1424 have "(x, Th th'') \<in> (RAG s)\<^sup>+" by auto |
|
1425 with th''_r show ?thesis by auto |
|
1426 qed |
|
1427 qed |
|
1428 qed |
|
1429 qed |
|
1430 qed |
|
1431 |
|
1432 text {* \noindent |
|
1433 The following is just an instance of @{text "chain_building"}. |
|
1434 *} |
|
1435 lemma th_chain_to_ready: |
|
1436 assumes th_in: "th \<in> threads s" |
|
1437 shows "th \<in> readys s \<or> (\<exists> th'. th' \<in> readys s \<and> (Th th, Th th') \<in> (RAG s)^+)" |
|
1438 proof(cases "th \<in> readys s") |
|
1439 case True |
|
1440 thus ?thesis by auto |
|
1441 next |
|
1442 case False |
|
1443 from False and th_in have "Th th \<in> Domain (RAG s)" |
|
1444 by (auto simp:readys_def s_waiting_def s_RAG_def wq_def cs_waiting_def Domain_def) |
|
1445 from chain_building [rule_format, OF this] |
|
1446 show ?thesis by auto |
|
1447 qed |
|
1448 |
|
1449 end |
|
1450 |
|
1451 lemma waiting_eq: "waiting s th cs = waiting (wq s) th cs" |
|
1452 by (unfold s_waiting_def cs_waiting_def wq_def, auto) |
|
1453 |
|
1454 lemma holding_eq: "holding (s::state) th cs = holding (wq s) th cs" |
|
1455 by (unfold s_holding_def wq_def cs_holding_def, simp) |
|
1456 |
|
1457 lemma holding_unique: "\<lbrakk>holding (s::state) th1 cs; holding s th2 cs\<rbrakk> \<Longrightarrow> th1 = th2" |
|
1458 by (unfold s_holding_def cs_holding_def, auto) |
|
1459 |
|
1460 context valid_trace |
|
1461 begin |
|
1462 |
|
1463 lemma unique_RAG: "\<lbrakk>(n, n1) \<in> RAG s; (n, n2) \<in> RAG s\<rbrakk> \<Longrightarrow> n1 = n2" |
|
1464 apply(unfold s_RAG_def, auto, fold waiting_eq holding_eq) |
|
1465 by(auto elim:waiting_unique holding_unique) |
|
1466 |
|
1467 end |
|
1468 |
|
1469 |
|
1470 lemma trancl_split: "(a, b) \<in> r^+ \<Longrightarrow> \<exists> c. (a, c) \<in> r" |
|
1471 by (induct rule:trancl_induct, auto) |
|
1472 |
|
1473 context valid_trace |
|
1474 begin |
|
1475 |
|
1476 lemma dchain_unique: |
|
1477 assumes th1_d: "(n, Th th1) \<in> (RAG s)^+" |
|
1478 and th1_r: "th1 \<in> readys s" |
|
1479 and th2_d: "(n, Th th2) \<in> (RAG s)^+" |
|
1480 and th2_r: "th2 \<in> readys s" |
|
1481 shows "th1 = th2" |
|
1482 proof - |
|
1483 { assume neq: "th1 \<noteq> th2" |
|
1484 hence "Th th1 \<noteq> Th th2" by simp |
|
1485 from unique_chain [OF _ th1_d th2_d this] and unique_RAG |
|
1486 have "(Th th1, Th th2) \<in> (RAG s)\<^sup>+ \<or> (Th th2, Th th1) \<in> (RAG s)\<^sup>+" by auto |
|
1487 hence "False" |
|
1488 proof |
|
1489 assume "(Th th1, Th th2) \<in> (RAG s)\<^sup>+" |
|
1490 from trancl_split [OF this] |
|
1491 obtain n where dd: "(Th th1, n) \<in> RAG s" by auto |
|
1492 then obtain cs where eq_n: "n = Cs cs" |
|
1493 by (auto simp:s_RAG_def s_holding_def cs_holding_def cs_waiting_def wq_def dest:hd_np_in) |
|
1494 from dd eq_n have "th1 \<notin> readys s" |
|
1495 by (auto simp:readys_def s_RAG_def wq_def s_waiting_def cs_waiting_def) |
|
1496 with th1_r show ?thesis by auto |
|
1497 next |
|
1498 assume "(Th th2, Th th1) \<in> (RAG s)\<^sup>+" |
|
1499 from trancl_split [OF this] |
|
1500 obtain n where dd: "(Th th2, n) \<in> RAG s" by auto |
|
1501 then obtain cs where eq_n: "n = Cs cs" |
|
1502 by (auto simp:s_RAG_def s_holding_def cs_holding_def cs_waiting_def wq_def dest:hd_np_in) |
|
1503 from dd eq_n have "th2 \<notin> readys s" |
|
1504 by (auto simp:readys_def wq_def s_RAG_def s_waiting_def cs_waiting_def) |
|
1505 with th2_r show ?thesis by auto |
|
1506 qed |
|
1507 } thus ?thesis by auto |
|
1508 qed |
|
1509 |
|
1510 end |
|
1511 |
|
1512 |
|
1513 lemma step_holdents_p_add: |
|
1514 fixes th cs s |
|
1515 assumes vt: "vt (P th cs#s)" |
|
1516 and "wq s cs = []" |
|
1517 shows "holdents (P th cs#s) th = holdents s th \<union> {cs}" |
|
1518 proof - |
|
1519 from assms show ?thesis |
|
1520 unfolding holdents_test step_RAG_p[OF vt] by (auto) |
|
1521 qed |
|
1522 |
|
1523 lemma step_holdents_p_eq: |
|
1524 fixes th cs s |
|
1525 assumes vt: "vt (P th cs#s)" |
|
1526 and "wq s cs \<noteq> []" |
|
1527 shows "holdents (P th cs#s) th = holdents s th" |
|
1528 proof - |
|
1529 from assms show ?thesis |
|
1530 unfolding holdents_test step_RAG_p[OF vt] by auto |
|
1531 qed |
|
1532 |
|
1533 |
|
1534 lemma (in valid_trace) finite_holding : |
|
1535 shows "finite (holdents s th)" |
|
1536 proof - |
|
1537 let ?F = "\<lambda> (x, y). the_cs x" |
|
1538 from finite_RAG |
|
1539 have "finite (RAG s)" . |
|
1540 hence "finite (?F `(RAG s))" by simp |
|
1541 moreover have "{cs . (Cs cs, Th th) \<in> RAG s} \<subseteq> \<dots>" |
|
1542 proof - |
|
1543 { have h: "\<And> a A f. a \<in> A \<Longrightarrow> f a \<in> f ` A" by auto |
|
1544 fix x assume "(Cs x, Th th) \<in> RAG s" |
|
1545 hence "?F (Cs x, Th th) \<in> ?F `(RAG s)" by (rule h) |
|
1546 moreover have "?F (Cs x, Th th) = x" by simp |
|
1547 ultimately have "x \<in> (\<lambda>(x, y). the_cs x) ` RAG s" by simp |
|
1548 } thus ?thesis by auto |
|
1549 qed |
|
1550 ultimately show ?thesis by (unfold holdents_test, auto intro:finite_subset) |
|
1551 qed |
|
1552 |
|
1553 lemma cntCS_v_dec: |
|
1554 fixes s thread cs |
|
1555 assumes vtv: "vt (V thread cs#s)" |
|
1556 shows "(cntCS (V thread cs#s) thread + 1) = cntCS s thread" |
|
1557 proof - |
|
1558 from vtv interpret vt_s: valid_trace s |
|
1559 by (cases, unfold_locales, simp) |
|
1560 from vtv interpret vt_v: valid_trace "V thread cs#s" |
|
1561 by (unfold_locales, simp) |
|
1562 from step_back_step[OF vtv] |
|
1563 have cs_in: "cs \<in> holdents s thread" |
|
1564 apply (cases, unfold holdents_test s_RAG_def, simp) |
|
1565 by (unfold cs_holding_def s_holding_def wq_def, auto) |
|
1566 moreover have cs_not_in: |
|
1567 "(holdents (V thread cs#s) thread) = holdents s thread - {cs}" |
|
1568 apply (insert vt_s.wq_distinct[of cs]) |
|
1569 apply (unfold holdents_test, unfold step_RAG_v[OF vtv], |
|
1570 auto simp:next_th_def) |
|
1571 proof - |
|
1572 fix rest |
|
1573 assume dst: "distinct (rest::thread list)" |
|
1574 and ne: "rest \<noteq> []" |
|
1575 and hd_ni: "hd (SOME q. distinct q \<and> set q = set rest) \<notin> set rest" |
|
1576 moreover have "set (SOME q. distinct q \<and> set q = set rest) = set rest" |
|
1577 proof(rule someI2) |
|
1578 from dst show "distinct rest \<and> set rest = set rest" by auto |
|
1579 next |
|
1580 show "\<And>x. distinct x \<and> set x = set rest \<Longrightarrow> set x = set rest" by auto |
|
1581 qed |
|
1582 ultimately have "hd (SOME q. distinct q \<and> set q = set rest) \<notin> |
|
1583 set (SOME q. distinct q \<and> set q = set rest)" by simp |
|
1584 moreover have "(SOME q. distinct q \<and> set q = set rest) \<noteq> []" |
|
1585 proof(rule someI2) |
|
1586 from dst show "distinct rest \<and> set rest = set rest" by auto |
|
1587 next |
|
1588 fix x assume " distinct x \<and> set x = set rest" with ne |
|
1589 show "x \<noteq> []" by auto |
|
1590 qed |
|
1591 ultimately |
|
1592 show "(Cs cs, Th (hd (SOME q. distinct q \<and> set q = set rest))) \<in> RAG s" |
|
1593 by auto |
|
1594 next |
|
1595 fix rest |
|
1596 assume dst: "distinct (rest::thread list)" |
|
1597 and ne: "rest \<noteq> []" |
|
1598 and hd_ni: "hd (SOME q. distinct q \<and> set q = set rest) \<notin> set rest" |
|
1599 moreover have "set (SOME q. distinct q \<and> set q = set rest) = set rest" |
|
1600 proof(rule someI2) |
|
1601 from dst show "distinct rest \<and> set rest = set rest" by auto |
|
1602 next |
|
1603 show "\<And>x. distinct x \<and> set x = set rest \<Longrightarrow> set x = set rest" by auto |
|
1604 qed |
|
1605 ultimately have "hd (SOME q. distinct q \<and> set q = set rest) \<notin> |
|
1606 set (SOME q. distinct q \<and> set q = set rest)" by simp |
|
1607 moreover have "(SOME q. distinct q \<and> set q = set rest) \<noteq> []" |
|
1608 proof(rule someI2) |
|
1609 from dst show "distinct rest \<and> set rest = set rest" by auto |
|
1610 next |
|
1611 fix x assume " distinct x \<and> set x = set rest" with ne |
|
1612 show "x \<noteq> []" by auto |
|
1613 qed |
|
1614 ultimately show "False" by auto |
|
1615 qed |
|
1616 ultimately |
|
1617 have "holdents s thread = insert cs (holdents (V thread cs#s) thread)" |
|
1618 by auto |
|
1619 moreover have "card \<dots> = |
|
1620 Suc (card ((holdents (V thread cs#s) thread) - {cs}))" |
|
1621 proof(rule card_insert) |
|
1622 from vt_v.finite_holding |
|
1623 show " finite (holdents (V thread cs # s) thread)" . |
|
1624 qed |
|
1625 moreover from cs_not_in |
|
1626 have "cs \<notin> (holdents (V thread cs#s) thread)" by auto |
|
1627 ultimately show ?thesis by (simp add:cntCS_def) |
|
1628 qed |
|
1629 |
|
1630 lemma count_rec1 [simp]: |
|
1631 assumes "Q e" |
|
1632 shows "count Q (e#es) = Suc (count Q es)" |
|
1633 using assms |
|
1634 by (unfold count_def, auto) |
|
1635 |
|
1636 lemma count_rec2 [simp]: |
|
1637 assumes "\<not>Q e" |
|
1638 shows "count Q (e#es) = (count Q es)" |
|
1639 using assms |
|
1640 by (unfold count_def, auto) |
|
1641 |
|
1642 lemma count_rec3 [simp]: |
|
1643 shows "count Q [] = 0" |
|
1644 by (unfold count_def, auto) |
|
1645 |
|
1646 lemma cntP_diff_inv: |
|
1647 assumes "cntP (e#s) th \<noteq> cntP s th" |
|
1648 shows "isP e \<and> actor e = th" |
|
1649 proof(cases e) |
|
1650 case (P th' pty) |
|
1651 show ?thesis |
|
1652 by (cases "(\<lambda>e. \<exists>cs. e = P th cs) (P th' pty)", |
|
1653 insert assms P, auto simp:cntP_def) |
|
1654 qed (insert assms, auto simp:cntP_def) |
|
1655 |
|
1656 lemma isP_E: |
|
1657 assumes "isP e" |
|
1658 obtains cs where "e = P (actor e) cs" |
|
1659 using assms by (cases e, auto) |
|
1660 |
|
1661 lemma isV_E: |
|
1662 assumes "isV e" |
|
1663 obtains cs where "e = V (actor e) cs" |
|
1664 using assms by (cases e, auto) (* ccc *) |
|
1665 |
|
1666 lemma cntV_diff_inv: |
|
1667 assumes "cntV (e#s) th \<noteq> cntV s th" |
|
1668 shows "isV e \<and> actor e = th" |
|
1669 proof(cases e) |
|
1670 case (V th' pty) |
|
1671 show ?thesis |
|
1672 by (cases "(\<lambda>e. \<exists>cs. e = V th cs) (V th' pty)", |
|
1673 insert assms V, auto simp:cntV_def) |
|
1674 qed (insert assms, auto simp:cntV_def) |
|
1675 |
|
1676 context valid_trace |
|
1677 begin |
|
1678 |
|
1679 text {* (* ddd *) \noindent |
|
1680 The relationship between @{text "cntP"}, @{text "cntV"} and @{text "cntCS"} |
|
1681 of one particular thread. |
|
1682 *} |
|
1683 |
|
1684 lemma cnp_cnv_cncs: |
|
1685 shows "cntP s th = cntV s th + (if (th \<in> readys s \<or> th \<notin> threads s) |
|
1686 then cntCS s th else cntCS s th + 1)" |
|
1687 proof - |
|
1688 from vt show ?thesis |
|
1689 proof(induct arbitrary:th) |
|
1690 case (vt_cons s e) |
|
1691 interpret vt_s: valid_trace s using vt_cons(1) by (unfold_locales, simp) |
|
1692 assume vt: "vt s" |
|
1693 and ih: "\<And>th. cntP s th = cntV s th + |
|
1694 (if (th \<in> readys s \<or> th \<notin> threads s) then cntCS s th else cntCS s th + 1)" |
|
1695 and stp: "step s e" |
|
1696 from stp show ?case |
|
1697 proof(cases) |
|
1698 case (thread_create thread prio) |
|
1699 assume eq_e: "e = Create thread prio" |
|
1700 and not_in: "thread \<notin> threads s" |
|
1701 show ?thesis |
|
1702 proof - |
|
1703 { fix cs |
|
1704 assume "thread \<in> set (wq s cs)" |
|
1705 from vt_s.wq_threads [OF this] have "thread \<in> threads s" . |
|
1706 with not_in have "False" by simp |
|
1707 } with eq_e have eq_readys: "readys (e#s) = readys s \<union> {thread}" |
|
1708 by (auto simp:readys_def threads.simps s_waiting_def |
|
1709 wq_def cs_waiting_def Let_def) |
|
1710 from eq_e have eq_cnp: "cntP (e#s) th = cntP s th" by (simp add:cntP_def count_def) |
|
1711 from eq_e have eq_cnv: "cntV (e#s) th = cntV s th" by (simp add:cntV_def count_def) |
|
1712 have eq_cncs: "cntCS (e#s) th = cntCS s th" |
|
1713 unfolding cntCS_def holdents_test |
|
1714 by (simp add:RAG_create_unchanged eq_e) |
|
1715 { assume "th \<noteq> thread" |
|
1716 with eq_readys eq_e |
|
1717 have "(th \<in> readys (e # s) \<or> th \<notin> threads (e # s)) = |
|
1718 (th \<in> readys (s) \<or> th \<notin> threads (s))" |
|
1719 by (simp add:threads.simps) |
|
1720 with eq_cnp eq_cnv eq_cncs ih not_in |
|
1721 have ?thesis by simp |
|
1722 } moreover { |
|
1723 assume eq_th: "th = thread" |
|
1724 with not_in ih have " cntP s th = cntV s th + cntCS s th" by simp |
|
1725 moreover from eq_th and eq_readys have "th \<in> readys (e#s)" by simp |
|
1726 moreover note eq_cnp eq_cnv eq_cncs |
|
1727 ultimately have ?thesis by auto |
|
1728 } ultimately show ?thesis by blast |
|
1729 qed |
|
1730 next |
|
1731 case (thread_exit thread) |
|
1732 assume eq_e: "e = Exit thread" |
|
1733 and is_runing: "thread \<in> runing s" |
|
1734 and no_hold: "holdents s thread = {}" |
|
1735 from eq_e have eq_cnp: "cntP (e#s) th = cntP s th" by (simp add:cntP_def count_def) |
|
1736 from eq_e have eq_cnv: "cntV (e#s) th = cntV s th" by (simp add:cntV_def count_def) |
|
1737 have eq_cncs: "cntCS (e#s) th = cntCS s th" |
|
1738 unfolding cntCS_def holdents_test |
|
1739 by (simp add:RAG_exit_unchanged eq_e) |
|
1740 { assume "th \<noteq> thread" |
|
1741 with eq_e |
|
1742 have "(th \<in> readys (e # s) \<or> th \<notin> threads (e # s)) = |
|
1743 (th \<in> readys (s) \<or> th \<notin> threads (s))" |
|
1744 apply (simp add:threads.simps readys_def) |
|
1745 apply (subst s_waiting_def) |
|
1746 apply (simp add:Let_def) |
|
1747 apply (subst s_waiting_def, simp) |
|
1748 done |
|
1749 with eq_cnp eq_cnv eq_cncs ih |
|
1750 have ?thesis by simp |
|
1751 } moreover { |
|
1752 assume eq_th: "th = thread" |
|
1753 with ih is_runing have " cntP s th = cntV s th + cntCS s th" |
|
1754 by (simp add:runing_def) |
|
1755 moreover from eq_th eq_e have "th \<notin> threads (e#s)" |
|
1756 by simp |
|
1757 moreover note eq_cnp eq_cnv eq_cncs |
|
1758 ultimately have ?thesis by auto |
|
1759 } ultimately show ?thesis by blast |
|
1760 next |
|
1761 case (thread_P thread cs) |
|
1762 assume eq_e: "e = P thread cs" |
|
1763 and is_runing: "thread \<in> runing s" |
|
1764 and no_dep: "(Cs cs, Th thread) \<notin> (RAG s)\<^sup>+" |
|
1765 from thread_P vt stp ih have vtp: "vt (P thread cs#s)" by auto |
|
1766 then interpret vt_p: valid_trace "(P thread cs#s)" |
|
1767 by (unfold_locales, simp) |
|
1768 show ?thesis |
|
1769 proof - |
|
1770 { have hh: "\<And> A B C. (B = C) \<Longrightarrow> (A \<and> B) = (A \<and> C)" by blast |
|
1771 assume neq_th: "th \<noteq> thread" |
|
1772 with eq_e |
|
1773 have eq_readys: "(th \<in> readys (e#s)) = (th \<in> readys (s))" |
|
1774 apply (simp add:readys_def s_waiting_def wq_def Let_def) |
|
1775 apply (rule_tac hh) |
|
1776 apply (intro iffI allI, clarify) |
|
1777 apply (erule_tac x = csa in allE, auto) |
|
1778 apply (subgoal_tac "wq_fun (schs s) cs \<noteq> []", auto) |
|
1779 apply (erule_tac x = cs in allE, auto) |
|
1780 by (case_tac "(wq_fun (schs s) cs)", auto) |
|
1781 moreover from neq_th eq_e have "cntCS (e # s) th = cntCS s th" |
|
1782 apply (simp add:cntCS_def holdents_test) |
|
1783 by (unfold step_RAG_p [OF vtp], auto) |
|
1784 moreover from eq_e neq_th have "cntP (e # s) th = cntP s th" |
|
1785 by (simp add:cntP_def count_def) |
|
1786 moreover from eq_e neq_th have "cntV (e#s) th = cntV s th" |
|
1787 by (simp add:cntV_def count_def) |
|
1788 moreover from eq_e neq_th have "threads (e#s) = threads s" by simp |
|
1789 moreover note ih [of th] |
|
1790 ultimately have ?thesis by simp |
|
1791 } moreover { |
|
1792 assume eq_th: "th = thread" |
|
1793 have ?thesis |
|
1794 proof - |
|
1795 from eq_e eq_th have eq_cnp: "cntP (e # s) th = 1 + (cntP s th)" |
|
1796 by (simp add:cntP_def count_def) |
|
1797 from eq_e eq_th have eq_cnv: "cntV (e#s) th = cntV s th" |
|
1798 by (simp add:cntV_def count_def) |
|
1799 show ?thesis |
|
1800 proof (cases "wq s cs = []") |
|
1801 case True |
|
1802 with is_runing |
|
1803 have "th \<in> readys (e#s)" |
|
1804 apply (unfold eq_e wq_def, unfold readys_def s_RAG_def) |
|
1805 apply (simp add: wq_def[symmetric] runing_def eq_th s_waiting_def) |
|
1806 by (auto simp:readys_def wq_def Let_def s_waiting_def wq_def) |
|
1807 moreover have "cntCS (e # s) th = 1 + cntCS s th" |
|
1808 proof - |
|
1809 have "card {csa. csa = cs \<or> (Cs csa, Th thread) \<in> RAG s} = |
|
1810 Suc (card {cs. (Cs cs, Th thread) \<in> RAG s})" (is "card ?L = Suc (card ?R)") |
|
1811 proof - |
|
1812 have "?L = insert cs ?R" by auto |
|
1813 moreover have "card \<dots> = Suc (card (?R - {cs}))" |
|
1814 proof(rule card_insert) |
|
1815 from vt_s.finite_holding [of thread] |
|
1816 show " finite {cs. (Cs cs, Th thread) \<in> RAG s}" |
|
1817 by (unfold holdents_test, simp) |
|
1818 qed |
|
1819 moreover have "?R - {cs} = ?R" |
|
1820 proof - |
|
1821 have "cs \<notin> ?R" |
|
1822 proof |
|
1823 assume "cs \<in> {cs. (Cs cs, Th thread) \<in> RAG s}" |
|
1824 with no_dep show False by auto |
|
1825 qed |
|
1826 thus ?thesis by auto |
|
1827 qed |
|
1828 ultimately show ?thesis by auto |
|
1829 qed |
|
1830 thus ?thesis |
|
1831 apply (unfold eq_e eq_th cntCS_def) |
|
1832 apply (simp add: holdents_test) |
|
1833 by (unfold step_RAG_p [OF vtp], auto simp:True) |
|
1834 qed |
|
1835 moreover from is_runing have "th \<in> readys s" |
|
1836 by (simp add:runing_def eq_th) |
|
1837 moreover note eq_cnp eq_cnv ih [of th] |
|
1838 ultimately show ?thesis by auto |
|
1839 next |
|
1840 case False |
|
1841 have eq_wq: "wq (e#s) cs = wq s cs @ [th]" |
|
1842 by (unfold eq_th eq_e wq_def, auto simp:Let_def) |
|
1843 have "th \<notin> readys (e#s)" |
|
1844 proof |
|
1845 assume "th \<in> readys (e#s)" |
|
1846 hence "\<forall>cs. \<not> waiting (e # s) th cs" by (simp add:readys_def) |
|
1847 from this[rule_format, of cs] have " \<not> waiting (e # s) th cs" . |
|
1848 hence "th \<in> set (wq (e#s) cs) \<Longrightarrow> th = hd (wq (e#s) cs)" |
|
1849 by (simp add:s_waiting_def wq_def) |
|
1850 moreover from eq_wq have "th \<in> set (wq (e#s) cs)" by auto |
|
1851 ultimately have "th = hd (wq (e#s) cs)" by blast |
|
1852 with eq_wq have "th = hd (wq s cs @ [th])" by simp |
|
1853 hence "th = hd (wq s cs)" using False by auto |
|
1854 with False eq_wq vt_p.wq_distinct [of cs] |
|
1855 show False by (fold eq_e, auto) |
|
1856 qed |
|
1857 moreover from is_runing have "th \<in> threads (e#s)" |
|
1858 by (unfold eq_e, auto simp:runing_def readys_def eq_th) |
|
1859 moreover have "cntCS (e # s) th = cntCS s th" |
|
1860 apply (unfold cntCS_def holdents_test eq_e step_RAG_p[OF vtp]) |
|
1861 by (auto simp:False) |
|
1862 moreover note eq_cnp eq_cnv ih[of th] |
|
1863 moreover from is_runing have "th \<in> readys s" |
|
1864 by (simp add:runing_def eq_th) |
|
1865 ultimately show ?thesis by auto |
|
1866 qed |
|
1867 qed |
|
1868 } ultimately show ?thesis by blast |
|
1869 qed |
|
1870 next |
|
1871 case (thread_V thread cs) |
|
1872 from assms vt stp ih thread_V have vtv: "vt (V thread cs # s)" by auto |
|
1873 then interpret vt_v: valid_trace "(V thread cs # s)" by (unfold_locales, simp) |
|
1874 assume eq_e: "e = V thread cs" |
|
1875 and is_runing: "thread \<in> runing s" |
|
1876 and hold: "holding s thread cs" |
|
1877 from hold obtain rest |
|
1878 where eq_wq: "wq s cs = thread # rest" |
|
1879 by (case_tac "wq s cs", auto simp: wq_def s_holding_def) |
|
1880 have eq_threads: "threads (e#s) = threads s" by (simp add: eq_e) |
|
1881 have eq_set: "set (SOME q. distinct q \<and> set q = set rest) = set rest" |
|
1882 proof(rule someI2) |
|
1883 from vt_v.wq_distinct[of cs] and eq_wq |
|
1884 show "distinct rest \<and> set rest = set rest" |
|
1885 by (metis distinct.simps(2) vt_s.wq_distinct) |
|
1886 next |
|
1887 show "\<And>x. distinct x \<and> set x = set rest \<Longrightarrow> set x = set rest" |
|
1888 by auto |
|
1889 qed |
|
1890 show ?thesis |
|
1891 proof - |
|
1892 { assume eq_th: "th = thread" |
|
1893 from eq_th have eq_cnp: "cntP (e # s) th = cntP s th" |
|
1894 by (unfold eq_e, simp add:cntP_def count_def) |
|
1895 moreover from eq_th have eq_cnv: "cntV (e#s) th = 1 + cntV s th" |
|
1896 by (unfold eq_e, simp add:cntV_def count_def) |
|
1897 moreover from cntCS_v_dec [OF vtv] |
|
1898 have "cntCS (e # s) thread + 1 = cntCS s thread" |
|
1899 by (simp add:eq_e) |
|
1900 moreover from is_runing have rd_before: "thread \<in> readys s" |
|
1901 by (unfold runing_def, simp) |
|
1902 moreover have "thread \<in> readys (e # s)" |
|
1903 proof - |
|
1904 from is_runing |
|
1905 have "thread \<in> threads (e#s)" |
|
1906 by (unfold eq_e, auto simp:runing_def readys_def) |
|
1907 moreover have "\<forall> cs1. \<not> waiting (e#s) thread cs1" |
|
1908 proof |
|
1909 fix cs1 |
|
1910 { assume eq_cs: "cs1 = cs" |
|
1911 have "\<not> waiting (e # s) thread cs1" |
|
1912 proof - |
|
1913 from eq_wq |
|
1914 have "thread \<notin> set (wq (e#s) cs1)" |
|
1915 apply(unfold eq_e wq_def eq_cs s_holding_def) |
|
1916 apply (auto simp:Let_def) |
|
1917 proof - |
|
1918 assume "thread \<in> set (SOME q. distinct q \<and> set q = set rest)" |
|
1919 with eq_set have "thread \<in> set rest" by simp |
|
1920 with vt_v.wq_distinct[of cs] |
|
1921 and eq_wq show False |
|
1922 by (metis distinct.simps(2) vt_s.wq_distinct) |
|
1923 qed |
|
1924 thus ?thesis by (simp add:wq_def s_waiting_def) |
|
1925 qed |
|
1926 } moreover { |
|
1927 assume neq_cs: "cs1 \<noteq> cs" |
|
1928 have "\<not> waiting (e # s) thread cs1" |
|
1929 proof - |
|
1930 from wq_v_neq [OF neq_cs[symmetric]] |
|
1931 have "wq (V thread cs # s) cs1 = wq s cs1" . |
|
1932 moreover have "\<not> waiting s thread cs1" |
|
1933 proof - |
|
1934 from runing_ready and is_runing |
|
1935 have "thread \<in> readys s" by auto |
|
1936 thus ?thesis by (simp add:readys_def) |
|
1937 qed |
|
1938 ultimately show ?thesis |
|
1939 by (auto simp:wq_def s_waiting_def eq_e) |
|
1940 qed |
|
1941 } ultimately show "\<not> waiting (e # s) thread cs1" by blast |
|
1942 qed |
|
1943 ultimately show ?thesis by (simp add:readys_def) |
|
1944 qed |
|
1945 moreover note eq_th ih |
|
1946 ultimately have ?thesis by auto |
|
1947 } moreover { |
|
1948 assume neq_th: "th \<noteq> thread" |
|
1949 from neq_th eq_e have eq_cnp: "cntP (e # s) th = cntP s th" |
|
1950 by (simp add:cntP_def count_def) |
|
1951 from neq_th eq_e have eq_cnv: "cntV (e # s) th = cntV s th" |
|
1952 by (simp add:cntV_def count_def) |
|
1953 have ?thesis |
|
1954 proof(cases "th \<in> set rest") |
|
1955 case False |
|
1956 have "(th \<in> readys (e # s)) = (th \<in> readys s)" |
|
1957 apply (insert step_back_vt[OF vtv]) |
|
1958 by (simp add: False eq_e eq_wq neq_th vt_s.readys_v_eq) |
|
1959 moreover have "cntCS (e#s) th = cntCS s th" |
|
1960 apply (insert neq_th, unfold eq_e cntCS_def holdents_test step_RAG_v[OF vtv], auto) |
|
1961 proof - |
|
1962 have "{csa. (Cs csa, Th th) \<in> RAG s \<or> csa = cs \<and> next_th s thread cs th} = |
|
1963 {cs. (Cs cs, Th th) \<in> RAG s}" |
|
1964 proof - |
|
1965 from False eq_wq |
|
1966 have " next_th s thread cs th \<Longrightarrow> (Cs cs, Th th) \<in> RAG s" |
|
1967 apply (unfold next_th_def, auto) |
|
1968 proof - |
|
1969 assume ne: "rest \<noteq> []" |
|
1970 and ni: "hd (SOME q. distinct q \<and> set q = set rest) \<notin> set rest" |
|
1971 and eq_wq: "wq s cs = thread # rest" |
|
1972 from eq_set ni have "hd (SOME q. distinct q \<and> set q = set rest) \<notin> |
|
1973 set (SOME q. distinct q \<and> set q = set rest) |
|
1974 " by simp |
|
1975 moreover have "(SOME q. distinct q \<and> set q = set rest) \<noteq> []" |
|
1976 proof(rule someI2) |
|
1977 from vt_s.wq_distinct[ of cs] and eq_wq |
|
1978 show "distinct rest \<and> set rest = set rest" by auto |
|
1979 next |
|
1980 fix x assume "distinct x \<and> set x = set rest" |
|
1981 with ne show "x \<noteq> []" by auto |
|
1982 qed |
|
1983 ultimately show |
|
1984 "(Cs cs, Th (hd (SOME q. distinct q \<and> set q = set rest))) \<in> RAG s" |
|
1985 by auto |
|
1986 qed |
|
1987 thus ?thesis by auto |
|
1988 qed |
|
1989 thus "card {csa. (Cs csa, Th th) \<in> RAG s \<or> csa = cs \<and> next_th s thread cs th} = |
|
1990 card {cs. (Cs cs, Th th) \<in> RAG s}" by simp |
|
1991 qed |
|
1992 moreover note ih eq_cnp eq_cnv eq_threads |
|
1993 ultimately show ?thesis by auto |
|
1994 next |
|
1995 case True |
|
1996 assume th_in: "th \<in> set rest" |
|
1997 show ?thesis |
|
1998 proof(cases "next_th s thread cs th") |
|
1999 case False |
|
2000 with eq_wq and th_in have |
|
2001 neq_hd: "th \<noteq> hd (SOME q. distinct q \<and> set q = set rest)" (is "th \<noteq> hd ?rest") |
|
2002 by (auto simp:next_th_def) |
|
2003 have "(th \<in> readys (e # s)) = (th \<in> readys s)" |
|
2004 proof - |
|
2005 from eq_wq and th_in |
|
2006 have "\<not> th \<in> readys s" |
|
2007 apply (auto simp:readys_def s_waiting_def) |
|
2008 apply (rule_tac x = cs in exI, auto) |
|
2009 by (insert vt_s.wq_distinct[of cs], auto simp add: wq_def) |
|
2010 moreover |
|
2011 from eq_wq and th_in and neq_hd |
|
2012 have "\<not> (th \<in> readys (e # s))" |
|
2013 apply (auto simp:readys_def s_waiting_def eq_e wq_def Let_def split:list.splits) |
|
2014 by (rule_tac x = cs in exI, auto simp:eq_set) |
|
2015 ultimately show ?thesis by auto |
|
2016 qed |
|
2017 moreover have "cntCS (e#s) th = cntCS s th" |
|
2018 proof - |
|
2019 from eq_wq and th_in and neq_hd |
|
2020 have "(holdents (e # s) th) = (holdents s th)" |
|
2021 apply (unfold eq_e step_RAG_v[OF vtv], |
|
2022 auto simp:next_th_def eq_set s_RAG_def holdents_test wq_def |
|
2023 Let_def cs_holding_def) |
|
2024 by (insert vt_s.wq_distinct[of cs], auto simp:wq_def) |
|
2025 thus ?thesis by (simp add:cntCS_def) |
|
2026 qed |
|
2027 moreover note ih eq_cnp eq_cnv eq_threads |
|
2028 ultimately show ?thesis by auto |
|
2029 next |
|
2030 case True |
|
2031 let ?rest = " (SOME q. distinct q \<and> set q = set rest)" |
|
2032 let ?t = "hd ?rest" |
|
2033 from True eq_wq th_in neq_th |
|
2034 have "th \<in> readys (e # s)" |
|
2035 apply (auto simp:eq_e readys_def s_waiting_def wq_def |
|
2036 Let_def next_th_def) |
|
2037 proof - |
|
2038 assume eq_wq: "wq_fun (schs s) cs = thread # rest" |
|
2039 and t_in: "?t \<in> set rest" |
|
2040 show "?t \<in> threads s" |
|
2041 proof(rule vt_s.wq_threads) |
|
2042 from eq_wq and t_in |
|
2043 show "?t \<in> set (wq s cs)" by (auto simp:wq_def) |
|
2044 qed |
|
2045 next |
|
2046 fix csa |
|
2047 assume eq_wq: "wq_fun (schs s) cs = thread # rest" |
|
2048 and t_in: "?t \<in> set rest" |
|
2049 and neq_cs: "csa \<noteq> cs" |
|
2050 and t_in': "?t \<in> set (wq_fun (schs s) csa)" |
|
2051 show "?t = hd (wq_fun (schs s) csa)" |
|
2052 proof - |
|
2053 { assume neq_hd': "?t \<noteq> hd (wq_fun (schs s) csa)" |
|
2054 from vt_s.wq_distinct[of cs] and |
|
2055 eq_wq[folded wq_def] and t_in eq_wq |
|
2056 have "?t \<noteq> thread" by auto |
|
2057 with eq_wq and t_in |
|
2058 have w1: "waiting s ?t cs" |
|
2059 by (auto simp:s_waiting_def wq_def) |
|
2060 from t_in' neq_hd' |
|
2061 have w2: "waiting s ?t csa" |
|
2062 by (auto simp:s_waiting_def wq_def) |
|
2063 from vt_s.waiting_unique[OF w1 w2] |
|
2064 and neq_cs have "False" by auto |
|
2065 } thus ?thesis by auto |
|
2066 qed |
|
2067 qed |
|
2068 moreover have "cntP s th = cntV s th + cntCS s th + 1" |
|
2069 proof - |
|
2070 have "th \<notin> readys s" |
|
2071 proof - |
|
2072 from True eq_wq neq_th th_in |
|
2073 show ?thesis |
|
2074 apply (unfold readys_def s_waiting_def, auto) |
|
2075 by (rule_tac x = cs in exI, auto simp add: wq_def) |
|
2076 qed |
|
2077 moreover have "th \<in> threads s" |
|
2078 proof - |
|
2079 from th_in eq_wq |
|
2080 have "th \<in> set (wq s cs)" by simp |
|
2081 from vt_s.wq_threads [OF this] |
|
2082 show ?thesis . |
|
2083 qed |
|
2084 ultimately show ?thesis using ih by auto |
|
2085 qed |
|
2086 moreover from True neq_th have "cntCS (e # s) th = 1 + cntCS s th" |
|
2087 apply (unfold cntCS_def holdents_test eq_e step_RAG_v[OF vtv], auto) |
|
2088 proof - |
|
2089 show "card {csa. (Cs csa, Th th) \<in> RAG s \<or> csa = cs} = |
|
2090 Suc (card {cs. (Cs cs, Th th) \<in> RAG s})" |
|
2091 (is "card ?A = Suc (card ?B)") |
|
2092 proof - |
|
2093 have "?A = insert cs ?B" by auto |
|
2094 hence "card ?A = card (insert cs ?B)" by simp |
|
2095 also have "\<dots> = Suc (card ?B)" |
|
2096 proof(rule card_insert_disjoint) |
|
2097 have "?B \<subseteq> ((\<lambda> (x, y). the_cs x) ` RAG s)" |
|
2098 apply (auto simp:image_def) |
|
2099 by (rule_tac x = "(Cs x, Th th)" in bexI, auto) |
|
2100 with vt_s.finite_RAG |
|
2101 show "finite {cs. (Cs cs, Th th) \<in> RAG s}" by (auto intro:finite_subset) |
|
2102 next |
|
2103 show "cs \<notin> {cs. (Cs cs, Th th) \<in> RAG s}" |
|
2104 proof |
|
2105 assume "cs \<in> {cs. (Cs cs, Th th) \<in> RAG s}" |
|
2106 hence "(Cs cs, Th th) \<in> RAG s" by simp |
|
2107 with True neq_th eq_wq show False |
|
2108 by (auto simp:next_th_def s_RAG_def cs_holding_def) |
|
2109 qed |
|
2110 qed |
|
2111 finally show ?thesis . |
|
2112 qed |
|
2113 qed |
|
2114 moreover note eq_cnp eq_cnv |
|
2115 ultimately show ?thesis by simp |
|
2116 qed |
|
2117 qed |
|
2118 } ultimately show ?thesis by blast |
|
2119 qed |
|
2120 next |
|
2121 case (thread_set thread prio) |
|
2122 assume eq_e: "e = Set thread prio" |
|
2123 and is_runing: "thread \<in> runing s" |
|
2124 show ?thesis |
|
2125 proof - |
|
2126 from eq_e have eq_cnp: "cntP (e#s) th = cntP s th" by (simp add:cntP_def count_def) |
|
2127 from eq_e have eq_cnv: "cntV (e#s) th = cntV s th" by (simp add:cntV_def count_def) |
|
2128 have eq_cncs: "cntCS (e#s) th = cntCS s th" |
|
2129 unfolding cntCS_def holdents_test |
|
2130 by (simp add:RAG_set_unchanged eq_e) |
|
2131 from eq_e have eq_readys: "readys (e#s) = readys s" |
|
2132 by (simp add:readys_def cs_waiting_def s_waiting_def wq_def, |
|
2133 auto simp:Let_def) |
|
2134 { assume "th \<noteq> thread" |
|
2135 with eq_readys eq_e |
|
2136 have "(th \<in> readys (e # s) \<or> th \<notin> threads (e # s)) = |
|
2137 (th \<in> readys (s) \<or> th \<notin> threads (s))" |
|
2138 by (simp add:threads.simps) |
|
2139 with eq_cnp eq_cnv eq_cncs ih is_runing |
|
2140 have ?thesis by simp |
|
2141 } moreover { |
|
2142 assume eq_th: "th = thread" |
|
2143 with is_runing ih have " cntP s th = cntV s th + cntCS s th" |
|
2144 by (unfold runing_def, auto) |
|
2145 moreover from eq_th and eq_readys is_runing have "th \<in> readys (e#s)" |
|
2146 by (simp add:runing_def) |
|
2147 moreover note eq_cnp eq_cnv eq_cncs |
|
2148 ultimately have ?thesis by auto |
|
2149 } ultimately show ?thesis by blast |
|
2150 qed |
|
2151 qed |
|
2152 next |
|
2153 case vt_nil |
|
2154 show ?case |
|
2155 by (unfold cntP_def cntV_def cntCS_def, |
|
2156 auto simp:count_def holdents_test s_RAG_def wq_def cs_holding_def) |
|
2157 qed |
|
2158 qed |
|
2159 |
|
2160 lemma not_thread_cncs: |
|
2161 assumes not_in: "th \<notin> threads s" |
|
2162 shows "cntCS s th = 0" |
|
2163 proof - |
|
2164 from vt not_in show ?thesis |
|
2165 proof(induct arbitrary:th) |
|
2166 case (vt_cons s e th) |
|
2167 interpret vt_s: valid_trace s using vt_cons(1) |
|
2168 by (unfold_locales, simp) |
|
2169 assume vt: "vt s" |
|
2170 and ih: "\<And>th. th \<notin> threads s \<Longrightarrow> cntCS s th = 0" |
|
2171 and stp: "step s e" |
|
2172 and not_in: "th \<notin> threads (e # s)" |
|
2173 from stp show ?case |
|
2174 proof(cases) |
|
2175 case (thread_create thread prio) |
|
2176 assume eq_e: "e = Create thread prio" |
|
2177 and not_in': "thread \<notin> threads s" |
|
2178 have "cntCS (e # s) th = cntCS s th" |
|
2179 apply (unfold eq_e cntCS_def holdents_test) |
|
2180 by (simp add:RAG_create_unchanged) |
|
2181 moreover have "th \<notin> threads s" |
|
2182 proof - |
|
2183 from not_in eq_e show ?thesis by simp |
|
2184 qed |
|
2185 moreover note ih ultimately show ?thesis by auto |
|
2186 next |
|
2187 case (thread_exit thread) |
|
2188 assume eq_e: "e = Exit thread" |
|
2189 and nh: "holdents s thread = {}" |
|
2190 have eq_cns: "cntCS (e # s) th = cntCS s th" |
|
2191 apply (unfold eq_e cntCS_def holdents_test) |
|
2192 by (simp add:RAG_exit_unchanged) |
|
2193 show ?thesis |
|
2194 proof(cases "th = thread") |
|
2195 case True |
|
2196 have "cntCS s th = 0" by (unfold cntCS_def, auto simp:nh True) |
|
2197 with eq_cns show ?thesis by simp |
|
2198 next |
|
2199 case False |
|
2200 with not_in and eq_e |
|
2201 have "th \<notin> threads s" by simp |
|
2202 from ih[OF this] and eq_cns show ?thesis by simp |
|
2203 qed |
|
2204 next |
|
2205 case (thread_P thread cs) |
|
2206 assume eq_e: "e = P thread cs" |
|
2207 and is_runing: "thread \<in> runing s" |
|
2208 from assms thread_P ih vt stp thread_P have vtp: "vt (P thread cs#s)" by auto |
|
2209 have neq_th: "th \<noteq> thread" |
|
2210 proof - |
|
2211 from not_in eq_e have "th \<notin> threads s" by simp |
|
2212 moreover from is_runing have "thread \<in> threads s" |
|
2213 by (simp add:runing_def readys_def) |
|
2214 ultimately show ?thesis by auto |
|
2215 qed |
|
2216 hence "cntCS (e # s) th = cntCS s th " |
|
2217 apply (unfold cntCS_def holdents_test eq_e) |
|
2218 by (unfold step_RAG_p[OF vtp], auto) |
|
2219 moreover have "cntCS s th = 0" |
|
2220 proof(rule ih) |
|
2221 from not_in eq_e show "th \<notin> threads s" by simp |
|
2222 qed |
|
2223 ultimately show ?thesis by simp |
|
2224 next |
|
2225 case (thread_V thread cs) |
|
2226 assume eq_e: "e = V thread cs" |
|
2227 and is_runing: "thread \<in> runing s" |
|
2228 and hold: "holding s thread cs" |
|
2229 have neq_th: "th \<noteq> thread" |
|
2230 proof - |
|
2231 from not_in eq_e have "th \<notin> threads s" by simp |
|
2232 moreover from is_runing have "thread \<in> threads s" |
|
2233 by (simp add:runing_def readys_def) |
|
2234 ultimately show ?thesis by auto |
|
2235 qed |
|
2236 from assms thread_V vt stp ih |
|
2237 have vtv: "vt (V thread cs#s)" by auto |
|
2238 then interpret vt_v: valid_trace "(V thread cs#s)" |
|
2239 by (unfold_locales, simp) |
|
2240 from hold obtain rest |
|
2241 where eq_wq: "wq s cs = thread # rest" |
|
2242 by (case_tac "wq s cs", auto simp: wq_def s_holding_def) |
|
2243 from not_in eq_e eq_wq |
|
2244 have "\<not> next_th s thread cs th" |
|
2245 apply (auto simp:next_th_def) |
|
2246 proof - |
|
2247 assume ne: "rest \<noteq> []" |
|
2248 and ni: "hd (SOME q. distinct q \<and> set q = set rest) \<notin> threads s" (is "?t \<notin> threads s") |
|
2249 have "?t \<in> set rest" |
|
2250 proof(rule someI2) |
|
2251 from vt_v.wq_distinct[of cs] and eq_wq |
|
2252 show "distinct rest \<and> set rest = set rest" |
|
2253 by (metis distinct.simps(2) vt_s.wq_distinct) |
|
2254 next |
|
2255 fix x assume "distinct x \<and> set x = set rest" with ne |
|
2256 show "hd x \<in> set rest" by (cases x, auto) |
|
2257 qed |
|
2258 with eq_wq have "?t \<in> set (wq s cs)" by simp |
|
2259 from vt_s.wq_threads[OF this] and ni |
|
2260 show False |
|
2261 using `hd (SOME q. distinct q \<and> set q = set rest) \<in> set (wq s cs)` |
|
2262 ni vt_s.wq_threads by blast |
|
2263 qed |
|
2264 moreover note neq_th eq_wq |
|
2265 ultimately have "cntCS (e # s) th = cntCS s th" |
|
2266 by (unfold eq_e cntCS_def holdents_test step_RAG_v[OF vtv], auto) |
|
2267 moreover have "cntCS s th = 0" |
|
2268 proof(rule ih) |
|
2269 from not_in eq_e show "th \<notin> threads s" by simp |
|
2270 qed |
|
2271 ultimately show ?thesis by simp |
|
2272 next |
|
2273 case (thread_set thread prio) |
|
2274 print_facts |
|
2275 assume eq_e: "e = Set thread prio" |
|
2276 and is_runing: "thread \<in> runing s" |
|
2277 from not_in and eq_e have "th \<notin> threads s" by auto |
|
2278 from ih [OF this] and eq_e |
|
2279 show ?thesis |
|
2280 apply (unfold eq_e cntCS_def holdents_test) |
|
2281 by (simp add:RAG_set_unchanged) |
|
2282 qed |
|
2283 next |
|
2284 case vt_nil |
|
2285 show ?case |
|
2286 by (unfold cntCS_def, |
|
2287 auto simp:count_def holdents_test s_RAG_def wq_def cs_holding_def) |
|
2288 qed |
|
2289 qed |
|
2290 |
|
2291 end |
|
2292 |
|
2293 lemma eq_waiting: "waiting (wq (s::state)) th cs = waiting s th cs" |
|
2294 by (auto simp:s_waiting_def cs_waiting_def wq_def) |
|
2295 |
|
2296 context valid_trace |
|
2297 begin |
|
2298 |
|
2299 lemma dm_RAG_threads: |
|
2300 assumes in_dom: "(Th th) \<in> Domain (RAG s)" |
|
2301 shows "th \<in> threads s" |
|
2302 proof - |
|
2303 from in_dom obtain n where "(Th th, n) \<in> RAG s" by auto |
|
2304 moreover from RAG_target_th[OF this] obtain cs where "n = Cs cs" by auto |
|
2305 ultimately have "(Th th, Cs cs) \<in> RAG s" by simp |
|
2306 hence "th \<in> set (wq s cs)" |
|
2307 by (unfold s_RAG_def, auto simp:cs_waiting_def) |
|
2308 from wq_threads [OF this] show ?thesis . |
|
2309 qed |
|
2310 |
|
2311 end |
|
2312 |
|
2313 lemma cp_eq_cpreced: "cp s th = cpreced (wq s) s th" |
|
2314 unfolding cp_def wq_def |
|
2315 apply(induct s rule: schs.induct) |
|
2316 thm cpreced_initial |
|
2317 apply(simp add: Let_def cpreced_initial) |
|
2318 apply(simp add: Let_def) |
|
2319 apply(simp add: Let_def) |
|
2320 apply(simp add: Let_def) |
|
2321 apply(subst (2) schs.simps) |
|
2322 apply(simp add: Let_def) |
|
2323 apply(subst (2) schs.simps) |
|
2324 apply(simp add: Let_def) |
|
2325 done |
|
2326 |
|
2327 context valid_trace |
|
2328 begin |
|
2329 |
|
2330 lemma runing_unique: |
|
2331 assumes runing_1: "th1 \<in> runing s" |
|
2332 and runing_2: "th2 \<in> runing s" |
|
2333 shows "th1 = th2" |
|
2334 proof - |
|
2335 from runing_1 and runing_2 have "cp s th1 = cp s th2" |
|
2336 unfolding runing_def |
|
2337 apply(simp) |
|
2338 done |
|
2339 hence eq_max: "Max ((\<lambda>th. preced th s) ` ({th1} \<union> dependants (wq s) th1)) = |
|
2340 Max ((\<lambda>th. preced th s) ` ({th2} \<union> dependants (wq s) th2))" |
|
2341 (is "Max (?f ` ?A) = Max (?f ` ?B)") |
|
2342 unfolding cp_eq_cpreced |
|
2343 unfolding cpreced_def . |
|
2344 obtain th1' where th1_in: "th1' \<in> ?A" and eq_f_th1: "?f th1' = Max (?f ` ?A)" |
|
2345 proof - |
|
2346 have h1: "finite (?f ` ?A)" |
|
2347 proof - |
|
2348 have "finite ?A" |
|
2349 proof - |
|
2350 have "finite (dependants (wq s) th1)" |
|
2351 proof- |
|
2352 have "finite {th'. (Th th', Th th1) \<in> (RAG (wq s))\<^sup>+}" |
|
2353 proof - |
|
2354 let ?F = "\<lambda> (x, y). the_th x" |
|
2355 have "{th'. (Th th', Th th1) \<in> (RAG (wq s))\<^sup>+} \<subseteq> ?F ` ((RAG (wq s))\<^sup>+)" |
|
2356 apply (auto simp:image_def) |
|
2357 by (rule_tac x = "(Th x, Th th1)" in bexI, auto) |
|
2358 moreover have "finite \<dots>" |
|
2359 proof - |
|
2360 from finite_RAG have "finite (RAG s)" . |
|
2361 hence "finite ((RAG (wq s))\<^sup>+)" |
|
2362 apply (unfold finite_trancl) |
|
2363 by (auto simp: s_RAG_def cs_RAG_def wq_def) |
|
2364 thus ?thesis by auto |
|
2365 qed |
|
2366 ultimately show ?thesis by (auto intro:finite_subset) |
|
2367 qed |
|
2368 thus ?thesis by (simp add:cs_dependants_def) |
|
2369 qed |
|
2370 thus ?thesis by simp |
|
2371 qed |
|
2372 thus ?thesis by auto |
|
2373 qed |
|
2374 moreover have h2: "(?f ` ?A) \<noteq> {}" |
|
2375 proof - |
|
2376 have "?A \<noteq> {}" by simp |
|
2377 thus ?thesis by simp |
|
2378 qed |
|
2379 from Max_in [OF h1 h2] |
|
2380 have "Max (?f ` ?A) \<in> (?f ` ?A)" . |
|
2381 thus ?thesis |
|
2382 thm cpreced_def |
|
2383 unfolding cpreced_def[symmetric] |
|
2384 unfolding cp_eq_cpreced[symmetric] |
|
2385 unfolding cpreced_def |
|
2386 using that[intro] by (auto) |
|
2387 qed |
|
2388 obtain th2' where th2_in: "th2' \<in> ?B" and eq_f_th2: "?f th2' = Max (?f ` ?B)" |
|
2389 proof - |
|
2390 have h1: "finite (?f ` ?B)" |
|
2391 proof - |
|
2392 have "finite ?B" |
|
2393 proof - |
|
2394 have "finite (dependants (wq s) th2)" |
|
2395 proof- |
|
2396 have "finite {th'. (Th th', Th th2) \<in> (RAG (wq s))\<^sup>+}" |
|
2397 proof - |
|
2398 let ?F = "\<lambda> (x, y). the_th x" |
|
2399 have "{th'. (Th th', Th th2) \<in> (RAG (wq s))\<^sup>+} \<subseteq> ?F ` ((RAG (wq s))\<^sup>+)" |
|
2400 apply (auto simp:image_def) |
|
2401 by (rule_tac x = "(Th x, Th th2)" in bexI, auto) |
|
2402 moreover have "finite \<dots>" |
|
2403 proof - |
|
2404 from finite_RAG have "finite (RAG s)" . |
|
2405 hence "finite ((RAG (wq s))\<^sup>+)" |
|
2406 apply (unfold finite_trancl) |
|
2407 by (auto simp: s_RAG_def cs_RAG_def wq_def) |
|
2408 thus ?thesis by auto |
|
2409 qed |
|
2410 ultimately show ?thesis by (auto intro:finite_subset) |
|
2411 qed |
|
2412 thus ?thesis by (simp add:cs_dependants_def) |
|
2413 qed |
|
2414 thus ?thesis by simp |
|
2415 qed |
|
2416 thus ?thesis by auto |
|
2417 qed |
|
2418 moreover have h2: "(?f ` ?B) \<noteq> {}" |
|
2419 proof - |
|
2420 have "?B \<noteq> {}" by simp |
|
2421 thus ?thesis by simp |
|
2422 qed |
|
2423 from Max_in [OF h1 h2] |
|
2424 have "Max (?f ` ?B) \<in> (?f ` ?B)" . |
|
2425 thus ?thesis by (auto intro:that) |
|
2426 qed |
|
2427 from eq_f_th1 eq_f_th2 eq_max |
|
2428 have eq_preced: "preced th1' s = preced th2' s" by auto |
|
2429 hence eq_th12: "th1' = th2'" |
|
2430 proof (rule preced_unique) |
|
2431 from th1_in have "th1' = th1 \<or> (th1' \<in> dependants (wq s) th1)" by simp |
|
2432 thus "th1' \<in> threads s" |
|
2433 proof |
|
2434 assume "th1' \<in> dependants (wq s) th1" |
|
2435 hence "(Th th1') \<in> Domain ((RAG s)^+)" |
|
2436 apply (unfold cs_dependants_def cs_RAG_def s_RAG_def) |
|
2437 by (auto simp:Domain_def) |
|
2438 hence "(Th th1') \<in> Domain (RAG s)" by (simp add:trancl_domain) |
|
2439 from dm_RAG_threads[OF this] show ?thesis . |
|
2440 next |
|
2441 assume "th1' = th1" |
|
2442 with runing_1 show ?thesis |
|
2443 by (unfold runing_def readys_def, auto) |
|
2444 qed |
|
2445 next |
|
2446 from th2_in have "th2' = th2 \<or> (th2' \<in> dependants (wq s) th2)" by simp |
|
2447 thus "th2' \<in> threads s" |
|
2448 proof |
|
2449 assume "th2' \<in> dependants (wq s) th2" |
|
2450 hence "(Th th2') \<in> Domain ((RAG s)^+)" |
|
2451 apply (unfold cs_dependants_def cs_RAG_def s_RAG_def) |
|
2452 by (auto simp:Domain_def) |
|
2453 hence "(Th th2') \<in> Domain (RAG s)" by (simp add:trancl_domain) |
|
2454 from dm_RAG_threads[OF this] show ?thesis . |
|
2455 next |
|
2456 assume "th2' = th2" |
|
2457 with runing_2 show ?thesis |
|
2458 by (unfold runing_def readys_def, auto) |
|
2459 qed |
|
2460 qed |
|
2461 from th1_in have "th1' = th1 \<or> th1' \<in> dependants (wq s) th1" by simp |
|
2462 thus ?thesis |
|
2463 proof |
|
2464 assume eq_th': "th1' = th1" |
|
2465 from th2_in have "th2' = th2 \<or> th2' \<in> dependants (wq s) th2" by simp |
|
2466 thus ?thesis |
|
2467 proof |
|
2468 assume "th2' = th2" thus ?thesis using eq_th' eq_th12 by simp |
|
2469 next |
|
2470 assume "th2' \<in> dependants (wq s) th2" |
|
2471 with eq_th12 eq_th' have "th1 \<in> dependants (wq s) th2" by simp |
|
2472 hence "(Th th1, Th th2) \<in> (RAG s)^+" |
|
2473 by (unfold cs_dependants_def s_RAG_def cs_RAG_def, simp) |
|
2474 hence "Th th1 \<in> Domain ((RAG s)^+)" |
|
2475 apply (unfold cs_dependants_def cs_RAG_def s_RAG_def) |
|
2476 by (auto simp:Domain_def) |
|
2477 hence "Th th1 \<in> Domain (RAG s)" by (simp add:trancl_domain) |
|
2478 then obtain n where d: "(Th th1, n) \<in> RAG s" by (auto simp:Domain_def) |
|
2479 from RAG_target_th [OF this] |
|
2480 obtain cs' where "n = Cs cs'" by auto |
|
2481 with d have "(Th th1, Cs cs') \<in> RAG s" by simp |
|
2482 with runing_1 have "False" |
|
2483 apply (unfold runing_def readys_def s_RAG_def) |
|
2484 by (auto simp:eq_waiting) |
|
2485 thus ?thesis by simp |
|
2486 qed |
|
2487 next |
|
2488 assume th1'_in: "th1' \<in> dependants (wq s) th1" |
|
2489 from th2_in have "th2' = th2 \<or> th2' \<in> dependants (wq s) th2" by simp |
|
2490 thus ?thesis |
|
2491 proof |
|
2492 assume "th2' = th2" |
|
2493 with th1'_in eq_th12 have "th2 \<in> dependants (wq s) th1" by simp |
|
2494 hence "(Th th2, Th th1) \<in> (RAG s)^+" |
|
2495 by (unfold cs_dependants_def s_RAG_def cs_RAG_def, simp) |
|
2496 hence "Th th2 \<in> Domain ((RAG s)^+)" |
|
2497 apply (unfold cs_dependants_def cs_RAG_def s_RAG_def) |
|
2498 by (auto simp:Domain_def) |
|
2499 hence "Th th2 \<in> Domain (RAG s)" by (simp add:trancl_domain) |
|
2500 then obtain n where d: "(Th th2, n) \<in> RAG s" by (auto simp:Domain_def) |
|
2501 from RAG_target_th [OF this] |
|
2502 obtain cs' where "n = Cs cs'" by auto |
|
2503 with d have "(Th th2, Cs cs') \<in> RAG s" by simp |
|
2504 with runing_2 have "False" |
|
2505 apply (unfold runing_def readys_def s_RAG_def) |
|
2506 by (auto simp:eq_waiting) |
|
2507 thus ?thesis by simp |
|
2508 next |
|
2509 assume "th2' \<in> dependants (wq s) th2" |
|
2510 with eq_th12 have "th1' \<in> dependants (wq s) th2" by simp |
|
2511 hence h1: "(Th th1', Th th2) \<in> (RAG s)^+" |
|
2512 by (unfold cs_dependants_def s_RAG_def cs_RAG_def, simp) |
|
2513 from th1'_in have h2: "(Th th1', Th th1) \<in> (RAG s)^+" |
|
2514 by (unfold cs_dependants_def s_RAG_def cs_RAG_def, simp) |
|
2515 show ?thesis |
|
2516 proof(rule dchain_unique[OF h1 _ h2, symmetric]) |
|
2517 from runing_1 show "th1 \<in> readys s" by (simp add:runing_def) |
|
2518 from runing_2 show "th2 \<in> readys s" by (simp add:runing_def) |
|
2519 qed |
|
2520 qed |
|
2521 qed |
|
2522 qed |
|
2523 |
|
2524 |
|
2525 lemma "card (runing s) \<le> 1" |
|
2526 apply(subgoal_tac "finite (runing s)") |
|
2527 prefer 2 |
|
2528 apply (metis finite_nat_set_iff_bounded lessI runing_unique) |
|
2529 apply(rule ccontr) |
|
2530 apply(simp) |
|
2531 apply(case_tac "Suc (Suc 0) \<le> card (runing s)") |
|
2532 apply(subst (asm) card_le_Suc_iff) |
|
2533 apply(simp) |
|
2534 apply(auto)[1] |
|
2535 apply (metis insertCI runing_unique) |
|
2536 apply(auto) |
|
2537 done |
|
2538 |
|
2539 end |
|
2540 |
|
2541 |
|
2542 lemma create_pre: |
|
2543 assumes stp: "step s e" |
|
2544 and not_in: "th \<notin> threads s" |
|
2545 and is_in: "th \<in> threads (e#s)" |
|
2546 obtains prio where "e = Create th prio" |
|
2547 proof - |
|
2548 from assms |
|
2549 show ?thesis |
|
2550 proof(cases) |
|
2551 case (thread_create thread prio) |
|
2552 with is_in not_in have "e = Create th prio" by simp |
|
2553 from that[OF this] show ?thesis . |
|
2554 next |
|
2555 case (thread_exit thread) |
|
2556 with assms show ?thesis by (auto intro!:that) |
|
2557 next |
|
2558 case (thread_P thread) |
|
2559 with assms show ?thesis by (auto intro!:that) |
|
2560 next |
|
2561 case (thread_V thread) |
|
2562 with assms show ?thesis by (auto intro!:that) |
|
2563 next |
|
2564 case (thread_set thread) |
|
2565 with assms show ?thesis by (auto intro!:that) |
|
2566 qed |
|
2567 qed |
|
2568 |
|
2569 lemma length_down_to_in: |
|
2570 assumes le_ij: "i \<le> j" |
|
2571 and le_js: "j \<le> length s" |
|
2572 shows "length (down_to j i s) = j - i" |
|
2573 proof - |
|
2574 have "length (down_to j i s) = length (from_to i j (rev s))" |
|
2575 by (unfold down_to_def, auto) |
|
2576 also have "\<dots> = j - i" |
|
2577 proof(rule length_from_to_in[OF le_ij]) |
|
2578 from le_js show "j \<le> length (rev s)" by simp |
|
2579 qed |
|
2580 finally show ?thesis . |
|
2581 qed |
|
2582 |
|
2583 |
|
2584 lemma moment_head: |
|
2585 assumes le_it: "Suc i \<le> length t" |
|
2586 obtains e where "moment (Suc i) t = e#moment i t" |
|
2587 proof - |
|
2588 have "i \<le> Suc i" by simp |
|
2589 from length_down_to_in [OF this le_it] |
|
2590 have "length (down_to (Suc i) i t) = 1" by auto |
|
2591 then obtain e where "down_to (Suc i) i t = [e]" |
|
2592 apply (cases "(down_to (Suc i) i t)") by auto |
|
2593 moreover have "down_to (Suc i) 0 t = down_to (Suc i) i t @ down_to i 0 t" |
|
2594 by (rule down_to_conc[symmetric], auto) |
|
2595 ultimately have eq_me: "moment (Suc i) t = e#(moment i t)" |
|
2596 by (auto simp:down_to_moment) |
|
2597 from that [OF this] show ?thesis . |
|
2598 qed |
|
2599 |
|
2600 context valid_trace |
|
2601 begin |
|
2602 |
|
2603 lemma cnp_cnv_eq: |
|
2604 assumes "th \<notin> threads s" |
|
2605 shows "cntP s th = cntV s th" |
|
2606 using assms |
|
2607 using cnp_cnv_cncs not_thread_cncs by auto |
|
2608 |
|
2609 end |
|
2610 |
|
2611 |
|
2612 lemma eq_RAG: |
|
2613 "RAG (wq s) = RAG s" |
|
2614 by (unfold cs_RAG_def s_RAG_def, auto) |
|
2615 |
|
2616 context valid_trace |
|
2617 begin |
|
2618 |
|
2619 lemma count_eq_dependants: |
|
2620 assumes eq_pv: "cntP s th = cntV s th" |
|
2621 shows "dependants (wq s) th = {}" |
|
2622 proof - |
|
2623 from cnp_cnv_cncs and eq_pv |
|
2624 have "cntCS s th = 0" |
|
2625 by (auto split:if_splits) |
|
2626 moreover have "finite {cs. (Cs cs, Th th) \<in> RAG s}" |
|
2627 proof - |
|
2628 from finite_holding[of th] show ?thesis |
|
2629 by (simp add:holdents_test) |
|
2630 qed |
|
2631 ultimately have h: "{cs. (Cs cs, Th th) \<in> RAG s} = {}" |
|
2632 by (unfold cntCS_def holdents_test cs_dependants_def, auto) |
|
2633 show ?thesis |
|
2634 proof(unfold cs_dependants_def) |
|
2635 { assume "{th'. (Th th', Th th) \<in> (RAG (wq s))\<^sup>+} \<noteq> {}" |
|
2636 then obtain th' where "(Th th', Th th) \<in> (RAG (wq s))\<^sup>+" by auto |
|
2637 hence "False" |
|
2638 proof(cases) |
|
2639 assume "(Th th', Th th) \<in> RAG (wq s)" |
|
2640 thus "False" by (auto simp:cs_RAG_def) |
|
2641 next |
|
2642 fix c |
|
2643 assume "(c, Th th) \<in> RAG (wq s)" |
|
2644 with h and eq_RAG show "False" |
|
2645 by (cases c, auto simp:cs_RAG_def) |
|
2646 qed |
|
2647 } thus "{th'. (Th th', Th th) \<in> (RAG (wq s))\<^sup>+} = {}" by auto |
|
2648 qed |
|
2649 qed |
|
2650 |
|
2651 lemma dependants_threads: |
|
2652 shows "dependants (wq s) th \<subseteq> threads s" |
|
2653 proof |
|
2654 { fix th th' |
|
2655 assume h: "th \<in> {th'a. (Th th'a, Th th') \<in> (RAG (wq s))\<^sup>+}" |
|
2656 have "Th th \<in> Domain (RAG s)" |
|
2657 proof - |
|
2658 from h obtain th' where "(Th th, Th th') \<in> (RAG (wq s))\<^sup>+" by auto |
|
2659 hence "(Th th) \<in> Domain ( (RAG (wq s))\<^sup>+)" by (auto simp:Domain_def) |
|
2660 with trancl_domain have "(Th th) \<in> Domain (RAG (wq s))" by simp |
|
2661 thus ?thesis using eq_RAG by simp |
|
2662 qed |
|
2663 from dm_RAG_threads[OF this] |
|
2664 have "th \<in> threads s" . |
|
2665 } note hh = this |
|
2666 fix th1 |
|
2667 assume "th1 \<in> dependants (wq s) th" |
|
2668 hence "th1 \<in> {th'a. (Th th'a, Th th) \<in> (RAG (wq s))\<^sup>+}" |
|
2669 by (unfold cs_dependants_def, simp) |
|
2670 from hh [OF this] show "th1 \<in> threads s" . |
|
2671 qed |
|
2672 |
|
2673 lemma finite_threads: |
|
2674 shows "finite (threads s)" |
|
2675 using vt by (induct) (auto elim: step.cases) |
|
2676 |
|
2677 end |
|
2678 |
|
2679 lemma Max_f_mono: |
|
2680 assumes seq: "A \<subseteq> B" |
|
2681 and np: "A \<noteq> {}" |
|
2682 and fnt: "finite B" |
|
2683 shows "Max (f ` A) \<le> Max (f ` B)" |
|
2684 proof(rule Max_mono) |
|
2685 from seq show "f ` A \<subseteq> f ` B" by auto |
|
2686 next |
|
2687 from np show "f ` A \<noteq> {}" by auto |
|
2688 next |
|
2689 from fnt and seq show "finite (f ` B)" by auto |
|
2690 qed |
|
2691 |
|
2692 context valid_trace |
|
2693 begin |
|
2694 |
|
2695 lemma cp_le: |
|
2696 assumes th_in: "th \<in> threads s" |
|
2697 shows "cp s th \<le> Max ((\<lambda> th. (preced th s)) ` threads s)" |
|
2698 proof(unfold cp_eq_cpreced cpreced_def cs_dependants_def) |
|
2699 show "Max ((\<lambda>th. preced th s) ` ({th} \<union> {th'. (Th th', Th th) \<in> (RAG (wq s))\<^sup>+})) |
|
2700 \<le> Max ((\<lambda>th. preced th s) ` threads s)" |
|
2701 (is "Max (?f ` ?A) \<le> Max (?f ` ?B)") |
|
2702 proof(rule Max_f_mono) |
|
2703 show "{th} \<union> {th'. (Th th', Th th) \<in> (RAG (wq s))\<^sup>+} \<noteq> {}" by simp |
|
2704 next |
|
2705 from finite_threads |
|
2706 show "finite (threads s)" . |
|
2707 next |
|
2708 from th_in |
|
2709 show "{th} \<union> {th'. (Th th', Th th) \<in> (RAG (wq s))\<^sup>+} \<subseteq> threads s" |
|
2710 apply (auto simp:Domain_def) |
|
2711 apply (rule_tac dm_RAG_threads) |
|
2712 apply (unfold trancl_domain [of "RAG s", symmetric]) |
|
2713 by (unfold cs_RAG_def s_RAG_def, auto simp:Domain_def) |
|
2714 qed |
|
2715 qed |
|
2716 |
|
2717 lemma le_cp: |
|
2718 shows "preced th s \<le> cp s th" |
|
2719 proof(unfold cp_eq_cpreced preced_def cpreced_def, simp) |
|
2720 show "Prc (priority th s) (last_set th s) |
|
2721 \<le> Max (insert (Prc (priority th s) (last_set th s)) |
|
2722 ((\<lambda>th. Prc (priority th s) (last_set th s)) ` dependants (wq s) th))" |
|
2723 (is "?l \<le> Max (insert ?l ?A)") |
|
2724 proof(cases "?A = {}") |
|
2725 case False |
|
2726 have "finite ?A" (is "finite (?f ` ?B)") |
|
2727 proof - |
|
2728 have "finite ?B" |
|
2729 proof- |
|
2730 have "finite {th'. (Th th', Th th) \<in> (RAG (wq s))\<^sup>+}" |
|
2731 proof - |
|
2732 let ?F = "\<lambda> (x, y). the_th x" |
|
2733 have "{th'. (Th th', Th th) \<in> (RAG (wq s))\<^sup>+} \<subseteq> ?F ` ((RAG (wq s))\<^sup>+)" |
|
2734 apply (auto simp:image_def) |
|
2735 by (rule_tac x = "(Th x, Th th)" in bexI, auto) |
|
2736 moreover have "finite \<dots>" |
|
2737 proof - |
|
2738 from finite_RAG have "finite (RAG s)" . |
|
2739 hence "finite ((RAG (wq s))\<^sup>+)" |
|
2740 apply (unfold finite_trancl) |
|
2741 by (auto simp: s_RAG_def cs_RAG_def wq_def) |
|
2742 thus ?thesis by auto |
|
2743 qed |
|
2744 ultimately show ?thesis by (auto intro:finite_subset) |
|
2745 qed |
|
2746 thus ?thesis by (simp add:cs_dependants_def) |
|
2747 qed |
|
2748 thus ?thesis by simp |
|
2749 qed |
|
2750 from Max_insert [OF this False, of ?l] show ?thesis by auto |
|
2751 next |
|
2752 case True |
|
2753 thus ?thesis by auto |
|
2754 qed |
|
2755 qed |
|
2756 |
|
2757 lemma max_cp_eq: |
|
2758 shows "Max ((cp s) ` threads s) = Max ((\<lambda> th. (preced th s)) ` threads s)" |
|
2759 (is "?l = ?r") |
|
2760 proof(cases "threads s = {}") |
|
2761 case True |
|
2762 thus ?thesis by auto |
|
2763 next |
|
2764 case False |
|
2765 have "?l \<in> ((cp s) ` threads s)" |
|
2766 proof(rule Max_in) |
|
2767 from finite_threads |
|
2768 show "finite (cp s ` threads s)" by auto |
|
2769 next |
|
2770 from False show "cp s ` threads s \<noteq> {}" by auto |
|
2771 qed |
|
2772 then obtain th |
|
2773 where th_in: "th \<in> threads s" and eq_l: "?l = cp s th" by auto |
|
2774 have "\<dots> \<le> ?r" by (rule cp_le[OF th_in]) |
|
2775 moreover have "?r \<le> cp s th" (is "Max (?f ` ?A) \<le> cp s th") |
|
2776 proof - |
|
2777 have "?r \<in> (?f ` ?A)" |
|
2778 proof(rule Max_in) |
|
2779 from finite_threads |
|
2780 show " finite ((\<lambda>th. preced th s) ` threads s)" by auto |
|
2781 next |
|
2782 from False show " (\<lambda>th. preced th s) ` threads s \<noteq> {}" by auto |
|
2783 qed |
|
2784 then obtain th' where |
|
2785 th_in': "th' \<in> ?A " and eq_r: "?r = ?f th'" by auto |
|
2786 from le_cp [of th'] eq_r |
|
2787 have "?r \<le> cp s th'" by auto |
|
2788 moreover have "\<dots> \<le> cp s th" |
|
2789 proof(fold eq_l) |
|
2790 show " cp s th' \<le> Max (cp s ` threads s)" |
|
2791 proof(rule Max_ge) |
|
2792 from th_in' show "cp s th' \<in> cp s ` threads s" |
|
2793 by auto |
|
2794 next |
|
2795 from finite_threads |
|
2796 show "finite (cp s ` threads s)" by auto |
|
2797 qed |
|
2798 qed |
|
2799 ultimately show ?thesis by auto |
|
2800 qed |
|
2801 ultimately show ?thesis using eq_l by auto |
|
2802 qed |
|
2803 |
|
2804 lemma max_cp_readys_threads_pre: |
|
2805 assumes np: "threads s \<noteq> {}" |
|
2806 shows "Max (cp s ` readys s) = Max (cp s ` threads s)" |
|
2807 proof(unfold max_cp_eq) |
|
2808 show "Max (cp s ` readys s) = Max ((\<lambda>th. preced th s) ` threads s)" |
|
2809 proof - |
|
2810 let ?p = "Max ((\<lambda>th. preced th s) ` threads s)" |
|
2811 let ?f = "(\<lambda>th. preced th s)" |
|
2812 have "?p \<in> ((\<lambda>th. preced th s) ` threads s)" |
|
2813 proof(rule Max_in) |
|
2814 from finite_threads show "finite (?f ` threads s)" by simp |
|
2815 next |
|
2816 from np show "?f ` threads s \<noteq> {}" by simp |
|
2817 qed |
|
2818 then obtain tm where tm_max: "?f tm = ?p" and tm_in: "tm \<in> threads s" |
|
2819 by (auto simp:Image_def) |
|
2820 from th_chain_to_ready [OF tm_in] |
|
2821 have "tm \<in> readys s \<or> (\<exists>th'. th' \<in> readys s \<and> (Th tm, Th th') \<in> (RAG s)\<^sup>+)" . |
|
2822 thus ?thesis |
|
2823 proof |
|
2824 assume "\<exists>th'. th' \<in> readys s \<and> (Th tm, Th th') \<in> (RAG s)\<^sup>+ " |
|
2825 then obtain th' where th'_in: "th' \<in> readys s" |
|
2826 and tm_chain:"(Th tm, Th th') \<in> (RAG s)\<^sup>+" by auto |
|
2827 have "cp s th' = ?f tm" |
|
2828 proof(subst cp_eq_cpreced, subst cpreced_def, rule Max_eqI) |
|
2829 from dependants_threads finite_threads |
|
2830 show "finite ((\<lambda>th. preced th s) ` ({th'} \<union> dependants (wq s) th'))" |
|
2831 by (auto intro:finite_subset) |
|
2832 next |
|
2833 fix p assume p_in: "p \<in> (\<lambda>th. preced th s) ` ({th'} \<union> dependants (wq s) th')" |
|
2834 from tm_max have " preced tm s = Max ((\<lambda>th. preced th s) ` threads s)" . |
|
2835 moreover have "p \<le> \<dots>" |
|
2836 proof(rule Max_ge) |
|
2837 from finite_threads |
|
2838 show "finite ((\<lambda>th. preced th s) ` threads s)" by simp |
|
2839 next |
|
2840 from p_in and th'_in and dependants_threads[of th'] |
|
2841 show "p \<in> (\<lambda>th. preced th s) ` threads s" |
|
2842 by (auto simp:readys_def) |
|
2843 qed |
|
2844 ultimately show "p \<le> preced tm s" by auto |
|
2845 next |
|
2846 show "preced tm s \<in> (\<lambda>th. preced th s) ` ({th'} \<union> dependants (wq s) th')" |
|
2847 proof - |
|
2848 from tm_chain |
|
2849 have "tm \<in> dependants (wq s) th'" |
|
2850 by (unfold cs_dependants_def s_RAG_def cs_RAG_def, auto) |
|
2851 thus ?thesis by auto |
|
2852 qed |
|
2853 qed |
|
2854 with tm_max |
|
2855 have h: "cp s th' = Max ((\<lambda>th. preced th s) ` threads s)" by simp |
|
2856 show ?thesis |
|
2857 proof (fold h, rule Max_eqI) |
|
2858 fix q |
|
2859 assume "q \<in> cp s ` readys s" |
|
2860 then obtain th1 where th1_in: "th1 \<in> readys s" |
|
2861 and eq_q: "q = cp s th1" by auto |
|
2862 show "q \<le> cp s th'" |
|
2863 apply (unfold h eq_q) |
|
2864 apply (unfold cp_eq_cpreced cpreced_def) |
|
2865 apply (rule Max_mono) |
|
2866 proof - |
|
2867 from dependants_threads [of th1] th1_in |
|
2868 show "(\<lambda>th. preced th s) ` ({th1} \<union> dependants (wq s) th1) \<subseteq> |
|
2869 (\<lambda>th. preced th s) ` threads s" |
|
2870 by (auto simp:readys_def) |
|
2871 next |
|
2872 show "(\<lambda>th. preced th s) ` ({th1} \<union> dependants (wq s) th1) \<noteq> {}" by simp |
|
2873 next |
|
2874 from finite_threads |
|
2875 show " finite ((\<lambda>th. preced th s) ` threads s)" by simp |
|
2876 qed |
|
2877 next |
|
2878 from finite_threads |
|
2879 show "finite (cp s ` readys s)" by (auto simp:readys_def) |
|
2880 next |
|
2881 from th'_in |
|
2882 show "cp s th' \<in> cp s ` readys s" by simp |
|
2883 qed |
|
2884 next |
|
2885 assume tm_ready: "tm \<in> readys s" |
|
2886 show ?thesis |
|
2887 proof(fold tm_max) |
|
2888 have cp_eq_p: "cp s tm = preced tm s" |
|
2889 proof(unfold cp_eq_cpreced cpreced_def, rule Max_eqI) |
|
2890 fix y |
|
2891 assume hy: "y \<in> (\<lambda>th. preced th s) ` ({tm} \<union> dependants (wq s) tm)" |
|
2892 show "y \<le> preced tm s" |
|
2893 proof - |
|
2894 { fix y' |
|
2895 assume hy' : "y' \<in> ((\<lambda>th. preced th s) ` dependants (wq s) tm)" |
|
2896 have "y' \<le> preced tm s" |
|
2897 proof(unfold tm_max, rule Max_ge) |
|
2898 from hy' dependants_threads[of tm] |
|
2899 show "y' \<in> (\<lambda>th. preced th s) ` threads s" by auto |
|
2900 next |
|
2901 from finite_threads |
|
2902 show "finite ((\<lambda>th. preced th s) ` threads s)" by simp |
|
2903 qed |
|
2904 } with hy show ?thesis by auto |
|
2905 qed |
|
2906 next |
|
2907 from dependants_threads[of tm] finite_threads |
|
2908 show "finite ((\<lambda>th. preced th s) ` ({tm} \<union> dependants (wq s) tm))" |
|
2909 by (auto intro:finite_subset) |
|
2910 next |
|
2911 show "preced tm s \<in> (\<lambda>th. preced th s) ` ({tm} \<union> dependants (wq s) tm)" |
|
2912 by simp |
|
2913 qed |
|
2914 moreover have "Max (cp s ` readys s) = cp s tm" |
|
2915 proof(rule Max_eqI) |
|
2916 from tm_ready show "cp s tm \<in> cp s ` readys s" by simp |
|
2917 next |
|
2918 from finite_threads |
|
2919 show "finite (cp s ` readys s)" by (auto simp:readys_def) |
|
2920 next |
|
2921 fix y assume "y \<in> cp s ` readys s" |
|
2922 then obtain th1 where th1_readys: "th1 \<in> readys s" |
|
2923 and h: "y = cp s th1" by auto |
|
2924 show "y \<le> cp s tm" |
|
2925 apply(unfold cp_eq_p h) |
|
2926 apply(unfold cp_eq_cpreced cpreced_def tm_max, rule Max_mono) |
|
2927 proof - |
|
2928 from finite_threads |
|
2929 show "finite ((\<lambda>th. preced th s) ` threads s)" by simp |
|
2930 next |
|
2931 show "(\<lambda>th. preced th s) ` ({th1} \<union> dependants (wq s) th1) \<noteq> {}" |
|
2932 by simp |
|
2933 next |
|
2934 from dependants_threads[of th1] th1_readys |
|
2935 show "(\<lambda>th. preced th s) ` ({th1} \<union> dependants (wq s) th1) |
|
2936 \<subseteq> (\<lambda>th. preced th s) ` threads s" |
|
2937 by (auto simp:readys_def) |
|
2938 qed |
|
2939 qed |
|
2940 ultimately show " Max (cp s ` readys s) = preced tm s" by simp |
|
2941 qed |
|
2942 qed |
|
2943 qed |
|
2944 qed |
|
2945 |
|
2946 text {* (* ccc *) \noindent |
|
2947 Since the current precedence of the threads in ready queue will always be boosted, |
|
2948 there must be one inside it has the maximum precedence of the whole system. |
|
2949 *} |
|
2950 lemma max_cp_readys_threads: |
|
2951 shows "Max (cp s ` readys s) = Max (cp s ` threads s)" |
|
2952 proof(cases "threads s = {}") |
|
2953 case True |
|
2954 thus ?thesis |
|
2955 by (auto simp:readys_def) |
|
2956 next |
|
2957 case False |
|
2958 show ?thesis by (rule max_cp_readys_threads_pre[OF False]) |
|
2959 qed |
|
2960 |
|
2961 end |
|
2962 |
|
2963 lemma eq_holding: "holding (wq s) th cs = holding s th cs" |
|
2964 apply (unfold s_holding_def cs_holding_def wq_def, simp) |
|
2965 done |
|
2966 |
|
2967 lemma f_image_eq: |
|
2968 assumes h: "\<And> a. a \<in> A \<Longrightarrow> f a = g a" |
|
2969 shows "f ` A = g ` A" |
|
2970 proof |
|
2971 show "f ` A \<subseteq> g ` A" |
|
2972 by(rule image_subsetI, auto intro:h) |
|
2973 next |
|
2974 show "g ` A \<subseteq> f ` A" |
|
2975 by (rule image_subsetI, auto intro:h[symmetric]) |
|
2976 qed |
|
2977 |
|
2978 |
|
2979 definition detached :: "state \<Rightarrow> thread \<Rightarrow> bool" |
|
2980 where "detached s th \<equiv> (\<not>(\<exists> cs. holding s th cs)) \<and> (\<not>(\<exists>cs. waiting s th cs))" |
|
2981 |
|
2982 |
|
2983 lemma detached_test: |
|
2984 shows "detached s th = (Th th \<notin> Field (RAG s))" |
|
2985 apply(simp add: detached_def Field_def) |
|
2986 apply(simp add: s_RAG_def) |
|
2987 apply(simp add: s_holding_abv s_waiting_abv) |
|
2988 apply(simp add: Domain_iff Range_iff) |
|
2989 apply(simp add: wq_def) |
|
2990 apply(auto) |
|
2991 done |
|
2992 |
|
2993 context valid_trace |
|
2994 begin |
|
2995 |
|
2996 lemma detached_intro: |
|
2997 assumes eq_pv: "cntP s th = cntV s th" |
|
2998 shows "detached s th" |
|
2999 proof - |
|
3000 from cnp_cnv_cncs |
|
3001 have eq_cnt: "cntP s th = |
|
3002 cntV s th + (if th \<in> readys s \<or> th \<notin> threads s then cntCS s th else cntCS s th + 1)" . |
|
3003 hence cncs_zero: "cntCS s th = 0" |
|
3004 by (auto simp:eq_pv split:if_splits) |
|
3005 with eq_cnt |
|
3006 have "th \<in> readys s \<or> th \<notin> threads s" by (auto simp:eq_pv) |
|
3007 thus ?thesis |
|
3008 proof |
|
3009 assume "th \<notin> threads s" |
|
3010 with range_in dm_RAG_threads |
|
3011 show ?thesis |
|
3012 by (auto simp add: detached_def s_RAG_def s_waiting_abv s_holding_abv wq_def Domain_iff Range_iff) |
|
3013 next |
|
3014 assume "th \<in> readys s" |
|
3015 moreover have "Th th \<notin> Range (RAG s)" |
|
3016 proof - |
|
3017 from card_0_eq [OF finite_holding] and cncs_zero |
|
3018 have "holdents s th = {}" |
|
3019 by (simp add:cntCS_def) |
|
3020 thus ?thesis |
|
3021 apply(auto simp:holdents_test) |
|
3022 apply(case_tac a) |
|
3023 apply(auto simp:holdents_test s_RAG_def) |
|
3024 done |
|
3025 qed |
|
3026 ultimately show ?thesis |
|
3027 by (auto simp add: detached_def s_RAG_def s_waiting_abv s_holding_abv wq_def readys_def) |
|
3028 qed |
|
3029 qed |
|
3030 |
|
3031 lemma detached_elim: |
|
3032 assumes dtc: "detached s th" |
|
3033 shows "cntP s th = cntV s th" |
|
3034 proof - |
|
3035 from cnp_cnv_cncs |
|
3036 have eq_pv: " cntP s th = |
|
3037 cntV s th + (if th \<in> readys s \<or> th \<notin> threads s then cntCS s th else cntCS s th + 1)" . |
|
3038 have cncs_z: "cntCS s th = 0" |
|
3039 proof - |
|
3040 from dtc have "holdents s th = {}" |
|
3041 unfolding detached_def holdents_test s_RAG_def |
|
3042 by (simp add: s_waiting_abv wq_def s_holding_abv Domain_iff Range_iff) |
|
3043 thus ?thesis by (auto simp:cntCS_def) |
|
3044 qed |
|
3045 show ?thesis |
|
3046 proof(cases "th \<in> threads s") |
|
3047 case True |
|
3048 with dtc |
|
3049 have "th \<in> readys s" |
|
3050 by (unfold readys_def detached_def Field_def Domain_def Range_def, |
|
3051 auto simp:eq_waiting s_RAG_def) |
|
3052 with cncs_z and eq_pv show ?thesis by simp |
|
3053 next |
|
3054 case False |
|
3055 with cncs_z and eq_pv show ?thesis by simp |
|
3056 qed |
|
3057 qed |
|
3058 |
|
3059 lemma detached_eq: |
|
3060 shows "(detached s th) = (cntP s th = cntV s th)" |
|
3061 by (insert vt, auto intro:detached_intro detached_elim) |
|
3062 |
|
3063 end |
|
3064 |
|
3065 text {* |
|
3066 The lemmas in this .thy file are all obvious lemmas, however, they still needs to be derived |
|
3067 from the concise and miniature model of PIP given in PrioGDef.thy. |
|
3068 *} |
|
3069 |
|
3070 lemma eq_dependants: "dependants (wq s) = dependants s" |
|
3071 by (simp add: s_dependants_abv wq_def) |
|
3072 |
|
3073 lemma next_th_unique: |
|
3074 assumes nt1: "next_th s th cs th1" |
|
3075 and nt2: "next_th s th cs th2" |
|
3076 shows "th1 = th2" |
|
3077 using assms by (unfold next_th_def, auto) |
|
3078 |
|
3079 lemma birth_time_lt: "s \<noteq> [] \<Longrightarrow> last_set th s < length s" |
|
3080 apply (induct s, simp) |
|
3081 proof - |
|
3082 fix a s |
|
3083 assume ih: "s \<noteq> [] \<Longrightarrow> last_set th s < length s" |
|
3084 and eq_as: "a # s \<noteq> []" |
|
3085 show "last_set th (a # s) < length (a # s)" |
|
3086 proof(cases "s \<noteq> []") |
|
3087 case False |
|
3088 from False show ?thesis |
|
3089 by (cases a, auto simp:last_set.simps) |
|
3090 next |
|
3091 case True |
|
3092 from ih [OF True] show ?thesis |
|
3093 by (cases a, auto simp:last_set.simps) |
|
3094 qed |
|
3095 qed |
|
3096 |
|
3097 lemma th_in_ne: "th \<in> threads s \<Longrightarrow> s \<noteq> []" |
|
3098 by (induct s, auto simp:threads.simps) |
|
3099 |
|
3100 lemma preced_tm_lt: "th \<in> threads s \<Longrightarrow> preced th s = Prc x y \<Longrightarrow> y < length s" |
|
3101 apply (drule_tac th_in_ne) |
|
3102 by (unfold preced_def, auto intro: birth_time_lt) |
|
3103 |
|
3104 lemma inj_the_preced: |
|
3105 "inj_on (the_preced s) (threads s)" |
|
3106 by (metis inj_onI preced_unique the_preced_def) |
|
3107 |
|
3108 lemma tRAG_alt_def: |
|
3109 "tRAG s = {(Th th1, Th th2) | th1 th2. |
|
3110 \<exists> cs. (Th th1, Cs cs) \<in> RAG s \<and> (Cs cs, Th th2) \<in> RAG s}" |
|
3111 by (auto simp:tRAG_def RAG_split wRAG_def hRAG_def) |
|
3112 |
|
3113 lemma tRAG_Field: |
|
3114 "Field (tRAG s) \<subseteq> Field (RAG s)" |
|
3115 by (unfold tRAG_alt_def Field_def, auto) |
|
3116 |
|
3117 lemma tRAG_ancestorsE: |
|
3118 assumes "x \<in> ancestors (tRAG s) u" |
|
3119 obtains th where "x = Th th" |
|
3120 proof - |
|
3121 from assms have "(u, x) \<in> (tRAG s)^+" |
|
3122 by (unfold ancestors_def, auto) |
|
3123 from tranclE[OF this] obtain c where "(c, x) \<in> tRAG s" by auto |
|
3124 then obtain th where "x = Th th" |
|
3125 by (unfold tRAG_alt_def, auto) |
|
3126 from that[OF this] show ?thesis . |
|
3127 qed |
|
3128 |
|
3129 lemma tRAG_mono: |
|
3130 assumes "RAG s' \<subseteq> RAG s" |
|
3131 shows "tRAG s' \<subseteq> tRAG s" |
|
3132 using assms |
|
3133 by (unfold tRAG_alt_def, auto) |
|
3134 |
|
3135 lemma holding_next_thI: |
|
3136 assumes "holding s th cs" |
|
3137 and "length (wq s cs) > 1" |
|
3138 obtains th' where "next_th s th cs th'" |
|
3139 proof - |
|
3140 from assms(1)[folded eq_holding, unfolded cs_holding_def] |
|
3141 have " th \<in> set (wq s cs) \<and> th = hd (wq s cs)" . |
|
3142 then obtain rest where h1: "wq s cs = th#rest" |
|
3143 by (cases "wq s cs", auto) |
|
3144 with assms(2) have h2: "rest \<noteq> []" by auto |
|
3145 let ?th' = "hd (SOME q. distinct q \<and> set q = set rest)" |
|
3146 have "next_th s th cs ?th'" using h1(1) h2 |
|
3147 by (unfold next_th_def, auto) |
|
3148 from that[OF this] show ?thesis . |
|
3149 qed |
|
3150 |
|
3151 lemma RAG_tRAG_transfer: |
|
3152 assumes "vt s'" |
|
3153 assumes "RAG s = RAG s' \<union> {(Th th, Cs cs)}" |
|
3154 and "(Cs cs, Th th'') \<in> RAG s'" |
|
3155 shows "tRAG s = tRAG s' \<union> {(Th th, Th th'')}" (is "?L = ?R") |
|
3156 proof - |
|
3157 interpret vt_s': valid_trace "s'" using assms(1) |
|
3158 by (unfold_locales, simp) |
|
3159 interpret rtree: rtree "RAG s'" |
|
3160 proof |
|
3161 show "single_valued (RAG s')" |
|
3162 apply (intro_locales) |
|
3163 by (unfold single_valued_def, |
|
3164 auto intro:vt_s'.unique_RAG) |
|
3165 |
|
3166 show "acyclic (RAG s')" |
|
3167 by (rule vt_s'.acyclic_RAG) |
|
3168 qed |
|
3169 { fix n1 n2 |
|
3170 assume "(n1, n2) \<in> ?L" |
|
3171 from this[unfolded tRAG_alt_def] |
|
3172 obtain th1 th2 cs' where |
|
3173 h: "n1 = Th th1" "n2 = Th th2" |
|
3174 "(Th th1, Cs cs') \<in> RAG s" |
|
3175 "(Cs cs', Th th2) \<in> RAG s" by auto |
|
3176 from h(4) and assms(2) have cs_in: "(Cs cs', Th th2) \<in> RAG s'" by auto |
|
3177 from h(3) and assms(2) |
|
3178 have "(Th th1, Cs cs') = (Th th, Cs cs) \<or> |
|
3179 (Th th1, Cs cs') \<in> RAG s'" by auto |
|
3180 hence "(n1, n2) \<in> ?R" |
|
3181 proof |
|
3182 assume h1: "(Th th1, Cs cs') = (Th th, Cs cs)" |
|
3183 hence eq_th1: "th1 = th" by simp |
|
3184 moreover have "th2 = th''" |
|
3185 proof - |
|
3186 from h1 have "cs' = cs" by simp |
|
3187 from assms(3) cs_in[unfolded this] rtree.sgv |
|
3188 show ?thesis |
|
3189 by (unfold single_valued_def, auto) |
|
3190 qed |
|
3191 ultimately show ?thesis using h(1,2) by auto |
|
3192 next |
|
3193 assume "(Th th1, Cs cs') \<in> RAG s'" |
|
3194 with cs_in have "(Th th1, Th th2) \<in> tRAG s'" |
|
3195 by (unfold tRAG_alt_def, auto) |
|
3196 from this[folded h(1, 2)] show ?thesis by auto |
|
3197 qed |
|
3198 } moreover { |
|
3199 fix n1 n2 |
|
3200 assume "(n1, n2) \<in> ?R" |
|
3201 hence "(n1, n2) \<in>tRAG s' \<or> (n1, n2) = (Th th, Th th'')" by auto |
|
3202 hence "(n1, n2) \<in> ?L" |
|
3203 proof |
|
3204 assume "(n1, n2) \<in> tRAG s'" |
|
3205 moreover have "... \<subseteq> ?L" |
|
3206 proof(rule tRAG_mono) |
|
3207 show "RAG s' \<subseteq> RAG s" by (unfold assms(2), auto) |
|
3208 qed |
|
3209 ultimately show ?thesis by auto |
|
3210 next |
|
3211 assume eq_n: "(n1, n2) = (Th th, Th th'')" |
|
3212 from assms(2, 3) have "(Cs cs, Th th'') \<in> RAG s" by auto |
|
3213 moreover have "(Th th, Cs cs) \<in> RAG s" using assms(2) by auto |
|
3214 ultimately show ?thesis |
|
3215 by (unfold eq_n tRAG_alt_def, auto) |
|
3216 qed |
|
3217 } ultimately show ?thesis by auto |
|
3218 qed |
|
3219 |
|
3220 context valid_trace |
|
3221 begin |
|
3222 |
|
3223 lemmas RAG_tRAG_transfer = RAG_tRAG_transfer[OF vt] |
|
3224 |
|
3225 end |
|
3226 |
|
3227 lemma cp_alt_def: |
|
3228 "cp s th = |
|
3229 Max ((the_preced s) ` {th'. Th th' \<in> (subtree (RAG s) (Th th))})" |
|
3230 proof - |
|
3231 have "Max (the_preced s ` ({th} \<union> dependants (wq s) th)) = |
|
3232 Max (the_preced s ` {th'. Th th' \<in> subtree (RAG s) (Th th)})" |
|
3233 (is "Max (_ ` ?L) = Max (_ ` ?R)") |
|
3234 proof - |
|
3235 have "?L = ?R" |
|
3236 by (auto dest:rtranclD simp:cs_dependants_def cs_RAG_def s_RAG_def subtree_def) |
|
3237 thus ?thesis by simp |
|
3238 qed |
|
3239 thus ?thesis by (unfold cp_eq_cpreced cpreced_def, fold the_preced_def, simp) |
|
3240 qed |
|
3241 |
|
3242 lemma cp_gen_alt_def: |
|
3243 "cp_gen s = (Max \<circ> (\<lambda>x. (the_preced s \<circ> the_thread) ` subtree (tRAG s) x))" |
|
3244 by (auto simp:cp_gen_def) |
|
3245 |
|
3246 lemma tRAG_nodeE: |
|
3247 assumes "(n1, n2) \<in> tRAG s" |
|
3248 obtains th1 th2 where "n1 = Th th1" "n2 = Th th2" |
|
3249 using assms |
|
3250 by (auto simp: tRAG_def wRAG_def hRAG_def tRAG_def) |
|
3251 |
|
3252 lemma subtree_nodeE: |
|
3253 assumes "n \<in> subtree (tRAG s) (Th th)" |
|
3254 obtains th1 where "n = Th th1" |
|
3255 proof - |
|
3256 show ?thesis |
|
3257 proof(rule subtreeE[OF assms]) |
|
3258 assume "n = Th th" |
|
3259 from that[OF this] show ?thesis . |
|
3260 next |
|
3261 assume "Th th \<in> ancestors (tRAG s) n" |
|
3262 hence "(n, Th th) \<in> (tRAG s)^+" by (auto simp:ancestors_def) |
|
3263 hence "\<exists> th1. n = Th th1" |
|
3264 proof(induct) |
|
3265 case (base y) |
|
3266 from tRAG_nodeE[OF this] show ?case by metis |
|
3267 next |
|
3268 case (step y z) |
|
3269 thus ?case by auto |
|
3270 qed |
|
3271 with that show ?thesis by auto |
|
3272 qed |
|
3273 qed |
|
3274 |
|
3275 lemma tRAG_star_RAG: "(tRAG s)^* \<subseteq> (RAG s)^*" |
|
3276 proof - |
|
3277 have "(wRAG s O hRAG s)^* \<subseteq> (RAG s O RAG s)^*" |
|
3278 by (rule rtrancl_mono, auto simp:RAG_split) |
|
3279 also have "... \<subseteq> ((RAG s)^*)^*" |
|
3280 by (rule rtrancl_mono, auto) |
|
3281 also have "... = (RAG s)^*" by simp |
|
3282 finally show ?thesis by (unfold tRAG_def, simp) |
|
3283 qed |
|
3284 |
|
3285 lemma tRAG_subtree_RAG: "subtree (tRAG s) x \<subseteq> subtree (RAG s) x" |
|
3286 proof - |
|
3287 { fix a |
|
3288 assume "a \<in> subtree (tRAG s) x" |
|
3289 hence "(a, x) \<in> (tRAG s)^*" by (auto simp:subtree_def) |
|
3290 with tRAG_star_RAG[of s] |
|
3291 have "(a, x) \<in> (RAG s)^*" by auto |
|
3292 hence "a \<in> subtree (RAG s) x" by (auto simp:subtree_def) |
|
3293 } thus ?thesis by auto |
|
3294 qed |
|
3295 |
|
3296 lemma tRAG_trancl_eq: |
|
3297 "{th'. (Th th', Th th) \<in> (tRAG s)^+} = |
|
3298 {th'. (Th th', Th th) \<in> (RAG s)^+}" |
|
3299 (is "?L = ?R") |
|
3300 proof - |
|
3301 { fix th' |
|
3302 assume "th' \<in> ?L" |
|
3303 hence "(Th th', Th th) \<in> (tRAG s)^+" by auto |
|
3304 from tranclD[OF this] |
|
3305 obtain z where h: "(Th th', z) \<in> tRAG s" "(z, Th th) \<in> (tRAG s)\<^sup>*" by auto |
|
3306 from tRAG_subtree_RAG[of s] and this(2) |
|
3307 have "(z, Th th) \<in> (RAG s)^*" by (meson subsetCE tRAG_star_RAG) |
|
3308 moreover from h(1) have "(Th th', z) \<in> (RAG s)^+" using tRAG_alt_def by auto |
|
3309 ultimately have "th' \<in> ?R" by auto |
|
3310 } moreover |
|
3311 { fix th' |
|
3312 assume "th' \<in> ?R" |
|
3313 hence "(Th th', Th th) \<in> (RAG s)^+" by (auto) |
|
3314 from plus_rpath[OF this] |
|
3315 obtain xs where rp: "rpath (RAG s) (Th th') xs (Th th)" "xs \<noteq> []" by auto |
|
3316 hence "(Th th', Th th) \<in> (tRAG s)^+" |
|
3317 proof(induct xs arbitrary:th' th rule:length_induct) |
|
3318 case (1 xs th' th) |
|
3319 then obtain x1 xs1 where Cons1: "xs = x1#xs1" by (cases xs, auto) |
|
3320 show ?case |
|
3321 proof(cases "xs1") |
|
3322 case Nil |
|
3323 from 1(2)[unfolded Cons1 Nil] |
|
3324 have rp: "rpath (RAG s) (Th th') [x1] (Th th)" . |
|
3325 hence "(Th th', x1) \<in> (RAG s)" by (cases, simp) |
|
3326 then obtain cs where "x1 = Cs cs" |
|
3327 by (unfold s_RAG_def, auto) |
|
3328 from rpath_nnl_lastE[OF rp[unfolded this]] |
|
3329 show ?thesis by auto |
|
3330 next |
|
3331 case (Cons x2 xs2) |
|
3332 from 1(2)[unfolded Cons1[unfolded this]] |
|
3333 have rp: "rpath (RAG s) (Th th') (x1 # x2 # xs2) (Th th)" . |
|
3334 from rpath_edges_on[OF this] |
|
3335 have eds: "edges_on (Th th' # x1 # x2 # xs2) \<subseteq> RAG s" . |
|
3336 have "(Th th', x1) \<in> edges_on (Th th' # x1 # x2 # xs2)" |
|
3337 by (simp add: edges_on_unfold) |
|
3338 with eds have rg1: "(Th th', x1) \<in> RAG s" by auto |
|
3339 then obtain cs1 where eq_x1: "x1 = Cs cs1" by (unfold s_RAG_def, auto) |
|
3340 have "(x1, x2) \<in> edges_on (Th th' # x1 # x2 # xs2)" |
|
3341 by (simp add: edges_on_unfold) |
|
3342 from this eds |
|
3343 have rg2: "(x1, x2) \<in> RAG s" by auto |
|
3344 from this[unfolded eq_x1] |
|
3345 obtain th1 where eq_x2: "x2 = Th th1" by (unfold s_RAG_def, auto) |
|
3346 from rg1[unfolded eq_x1] rg2[unfolded eq_x1 eq_x2] |
|
3347 have rt1: "(Th th', Th th1) \<in> tRAG s" by (unfold tRAG_alt_def, auto) |
|
3348 from rp have "rpath (RAG s) x2 xs2 (Th th)" |
|
3349 by (elim rpath_ConsE, simp) |
|
3350 from this[unfolded eq_x2] have rp': "rpath (RAG s) (Th th1) xs2 (Th th)" . |
|
3351 show ?thesis |
|
3352 proof(cases "xs2 = []") |
|
3353 case True |
|
3354 from rpath_nilE[OF rp'[unfolded this]] |
|
3355 have "th1 = th" by auto |
|
3356 from rt1[unfolded this] show ?thesis by auto |
|
3357 next |
|
3358 case False |
|
3359 from 1(1)[rule_format, OF _ rp' this, unfolded Cons1 Cons] |
|
3360 have "(Th th1, Th th) \<in> (tRAG s)\<^sup>+" by simp |
|
3361 with rt1 show ?thesis by auto |
|
3362 qed |
|
3363 qed |
|
3364 qed |
|
3365 hence "th' \<in> ?L" by auto |
|
3366 } ultimately show ?thesis by blast |
|
3367 qed |
|
3368 |
|
3369 lemma tRAG_trancl_eq_Th: |
|
3370 "{Th th' | th'. (Th th', Th th) \<in> (tRAG s)^+} = |
|
3371 {Th th' | th'. (Th th', Th th) \<in> (RAG s)^+}" |
|
3372 using tRAG_trancl_eq by auto |
|
3373 |
|
3374 lemma dependants_alt_def: |
|
3375 "dependants s th = {th'. (Th th', Th th) \<in> (tRAG s)^+}" |
|
3376 by (metis eq_RAG s_dependants_def tRAG_trancl_eq) |
|
3377 |
|
3378 context valid_trace |
|
3379 begin |
|
3380 |
|
3381 lemma count_eq_tRAG_plus: |
|
3382 assumes "cntP s th = cntV s th" |
|
3383 shows "{th'. (Th th', Th th) \<in> (tRAG s)^+} = {}" |
|
3384 using assms count_eq_dependants dependants_alt_def eq_dependants by auto |
|
3385 |
|
3386 lemma count_eq_RAG_plus: |
|
3387 assumes "cntP s th = cntV s th" |
|
3388 shows "{th'. (Th th', Th th) \<in> (RAG s)^+} = {}" |
|
3389 using assms count_eq_dependants cs_dependants_def eq_RAG by auto |
|
3390 |
|
3391 lemma count_eq_RAG_plus_Th: |
|
3392 assumes "cntP s th = cntV s th" |
|
3393 shows "{Th th' | th'. (Th th', Th th) \<in> (RAG s)^+} = {}" |
|
3394 using count_eq_RAG_plus[OF assms] by auto |
|
3395 |
|
3396 lemma count_eq_tRAG_plus_Th: |
|
3397 assumes "cntP s th = cntV s th" |
|
3398 shows "{Th th' | th'. (Th th', Th th) \<in> (tRAG s)^+} = {}" |
|
3399 using count_eq_tRAG_plus[OF assms] by auto |
|
3400 |
|
3401 end |
|
3402 |
|
3403 lemma tRAG_subtree_eq: |
|
3404 "(subtree (tRAG s) (Th th)) = {Th th' | th'. Th th' \<in> (subtree (RAG s) (Th th))}" |
|
3405 (is "?L = ?R") |
|
3406 proof - |
|
3407 { fix n |
|
3408 assume h: "n \<in> ?L" |
|
3409 hence "n \<in> ?R" |
|
3410 by (smt mem_Collect_eq subsetCE subtree_def subtree_nodeE tRAG_subtree_RAG) |
|
3411 } moreover { |
|
3412 fix n |
|
3413 assume "n \<in> ?R" |
|
3414 then obtain th' where h: "n = Th th'" "(Th th', Th th) \<in> (RAG s)^*" |
|
3415 by (auto simp:subtree_def) |
|
3416 from rtranclD[OF this(2)] |
|
3417 have "n \<in> ?L" |
|
3418 proof |
|
3419 assume "Th th' \<noteq> Th th \<and> (Th th', Th th) \<in> (RAG s)\<^sup>+" |
|
3420 with h have "n \<in> {Th th' | th'. (Th th', Th th) \<in> (RAG s)^+}" by auto |
|
3421 thus ?thesis using subtree_def tRAG_trancl_eq by fastforce |
|
3422 qed (insert h, auto simp:subtree_def) |
|
3423 } ultimately show ?thesis by auto |
|
3424 qed |
|
3425 |
|
3426 lemma threads_set_eq: |
|
3427 "the_thread ` (subtree (tRAG s) (Th th)) = |
|
3428 {th'. Th th' \<in> (subtree (RAG s) (Th th))}" (is "?L = ?R") |
|
3429 by (auto intro:rev_image_eqI simp:tRAG_subtree_eq) |
|
3430 |
|
3431 lemma cp_alt_def1: |
|
3432 "cp s th = Max ((the_preced s o the_thread) ` (subtree (tRAG s) (Th th)))" |
|
3433 proof - |
|
3434 have "(the_preced s ` the_thread ` subtree (tRAG s) (Th th)) = |
|
3435 ((the_preced s \<circ> the_thread) ` subtree (tRAG s) (Th th))" |
|
3436 by auto |
|
3437 thus ?thesis by (unfold cp_alt_def, fold threads_set_eq, auto) |
|
3438 qed |
|
3439 |
|
3440 lemma cp_gen_def_cond: |
|
3441 assumes "x = Th th" |
|
3442 shows "cp s th = cp_gen s (Th th)" |
|
3443 by (unfold cp_alt_def1 cp_gen_def, simp) |
|
3444 |
|
3445 lemma cp_gen_over_set: |
|
3446 assumes "\<forall> x \<in> A. \<exists> th. x = Th th" |
|
3447 shows "cp_gen s ` A = (cp s \<circ> the_thread) ` A" |
|
3448 proof(rule f_image_eq) |
|
3449 fix a |
|
3450 assume "a \<in> A" |
|
3451 from assms[rule_format, OF this] |
|
3452 obtain th where eq_a: "a = Th th" by auto |
|
3453 show "cp_gen s a = (cp s \<circ> the_thread) a" |
|
3454 by (unfold eq_a, simp, unfold cp_gen_def_cond[OF refl[of "Th th"]], simp) |
|
3455 qed |
|
3456 |
|
3457 |
|
3458 context valid_trace |
|
3459 begin |
|
3460 |
|
3461 lemma RAG_threads: |
|
3462 assumes "(Th th) \<in> Field (RAG s)" |
|
3463 shows "th \<in> threads s" |
|
3464 using assms |
|
3465 by (metis Field_def UnE dm_RAG_threads range_in vt) |
|
3466 |
|
3467 lemma subtree_tRAG_thread: |
|
3468 assumes "th \<in> threads s" |
|
3469 shows "subtree (tRAG s) (Th th) \<subseteq> Th ` threads s" (is "?L \<subseteq> ?R") |
|
3470 proof - |
|
3471 have "?L = {Th th' |th'. Th th' \<in> subtree (RAG s) (Th th)}" |
|
3472 by (unfold tRAG_subtree_eq, simp) |
|
3473 also have "... \<subseteq> ?R" |
|
3474 proof |
|
3475 fix x |
|
3476 assume "x \<in> {Th th' |th'. Th th' \<in> subtree (RAG s) (Th th)}" |
|
3477 then obtain th' where h: "x = Th th'" "Th th' \<in> subtree (RAG s) (Th th)" by auto |
|
3478 from this(2) |
|
3479 show "x \<in> ?R" |
|
3480 proof(cases rule:subtreeE) |
|
3481 case 1 |
|
3482 thus ?thesis by (simp add: assms h(1)) |
|
3483 next |
|
3484 case 2 |
|
3485 thus ?thesis by (metis ancestors_Field dm_RAG_threads h(1) image_eqI) |
|
3486 qed |
|
3487 qed |
|
3488 finally show ?thesis . |
|
3489 qed |
|
3490 |
|
3491 lemma readys_root: |
|
3492 assumes "th \<in> readys s" |
|
3493 shows "root (RAG s) (Th th)" |
|
3494 proof - |
|
3495 { fix x |
|
3496 assume "x \<in> ancestors (RAG s) (Th th)" |
|
3497 hence h: "(Th th, x) \<in> (RAG s)^+" by (auto simp:ancestors_def) |
|
3498 from tranclD[OF this] |
|
3499 obtain z where "(Th th, z) \<in> RAG s" by auto |
|
3500 with assms(1) have False |
|
3501 apply (case_tac z, auto simp:readys_def s_RAG_def s_waiting_def cs_waiting_def) |
|
3502 by (fold wq_def, blast) |
|
3503 } thus ?thesis by (unfold root_def, auto) |
|
3504 qed |
|
3505 |
|
3506 lemma readys_in_no_subtree: |
|
3507 assumes "th \<in> readys s" |
|
3508 and "th' \<noteq> th" |
|
3509 shows "Th th \<notin> subtree (RAG s) (Th th')" |
|
3510 proof |
|
3511 assume "Th th \<in> subtree (RAG s) (Th th')" |
|
3512 thus False |
|
3513 proof(cases rule:subtreeE) |
|
3514 case 1 |
|
3515 with assms show ?thesis by auto |
|
3516 next |
|
3517 case 2 |
|
3518 with readys_root[OF assms(1)] |
|
3519 show ?thesis by (auto simp:root_def) |
|
3520 qed |
|
3521 qed |
|
3522 |
|
3523 lemma not_in_thread_isolated: |
|
3524 assumes "th \<notin> threads s" |
|
3525 shows "(Th th) \<notin> Field (RAG s)" |
|
3526 proof |
|
3527 assume "(Th th) \<in> Field (RAG s)" |
|
3528 with dm_RAG_threads and range_in assms |
|
3529 show False by (unfold Field_def, blast) |
|
3530 qed |
|
3531 |
|
3532 lemma wf_RAG: "wf (RAG s)" |
|
3533 proof(rule finite_acyclic_wf) |
|
3534 from finite_RAG show "finite (RAG s)" . |
|
3535 next |
|
3536 from acyclic_RAG show "acyclic (RAG s)" . |
|
3537 qed |
|
3538 |
|
3539 lemma sgv_wRAG: "single_valued (wRAG s)" |
|
3540 using waiting_unique |
|
3541 by (unfold single_valued_def wRAG_def, auto) |
|
3542 |
|
3543 lemma sgv_hRAG: "single_valued (hRAG s)" |
|
3544 using holding_unique |
|
3545 by (unfold single_valued_def hRAG_def, auto) |
|
3546 |
|
3547 lemma sgv_tRAG: "single_valued (tRAG s)" |
|
3548 by (unfold tRAG_def, rule single_valued_relcomp, |
|
3549 insert sgv_wRAG sgv_hRAG, auto) |
|
3550 |
|
3551 lemma acyclic_tRAG: "acyclic (tRAG s)" |
|
3552 proof(unfold tRAG_def, rule acyclic_compose) |
|
3553 show "acyclic (RAG s)" using acyclic_RAG . |
|
3554 next |
|
3555 show "wRAG s \<subseteq> RAG s" unfolding RAG_split by auto |
|
3556 next |
|
3557 show "hRAG s \<subseteq> RAG s" unfolding RAG_split by auto |
|
3558 qed |
|
3559 |
|
3560 lemma sgv_RAG: "single_valued (RAG s)" |
|
3561 using unique_RAG by (auto simp:single_valued_def) |
|
3562 |
|
3563 lemma rtree_RAG: "rtree (RAG s)" |
|
3564 using sgv_RAG acyclic_RAG |
|
3565 by (unfold rtree_def rtree_axioms_def sgv_def, auto) |
|
3566 |
|
3567 end |
|
3568 |
|
3569 sublocale valid_trace < rtree_RAG: rtree "RAG s" |
|
3570 proof |
|
3571 show "single_valued (RAG s)" |
|
3572 apply (intro_locales) |
|
3573 by (unfold single_valued_def, |
|
3574 auto intro:unique_RAG) |
|
3575 |
|
3576 show "acyclic (RAG s)" |
|
3577 by (rule acyclic_RAG) |
|
3578 qed |
|
3579 |
|
3580 sublocale valid_trace < rtree_s: rtree "tRAG s" |
|
3581 proof(unfold_locales) |
|
3582 from sgv_tRAG show "single_valued (tRAG s)" . |
|
3583 next |
|
3584 from acyclic_tRAG show "acyclic (tRAG s)" . |
|
3585 qed |
|
3586 |
|
3587 sublocale valid_trace < fsbtRAGs : fsubtree "RAG s" |
|
3588 proof - |
|
3589 show "fsubtree (RAG s)" |
|
3590 proof(intro_locales) |
|
3591 show "fbranch (RAG s)" using finite_fbranchI[OF finite_RAG] . |
|
3592 next |
|
3593 show "fsubtree_axioms (RAG s)" |
|
3594 proof(unfold fsubtree_axioms_def) |
|
3595 from wf_RAG show "wf (RAG s)" . |
|
3596 qed |
|
3597 qed |
|
3598 qed |
|
3599 |
|
3600 sublocale valid_trace < fsbttRAGs: fsubtree "tRAG s" |
|
3601 proof - |
|
3602 have "fsubtree (tRAG s)" |
|
3603 proof - |
|
3604 have "fbranch (tRAG s)" |
|
3605 proof(unfold tRAG_def, rule fbranch_compose) |
|
3606 show "fbranch (wRAG s)" |
|
3607 proof(rule finite_fbranchI) |
|
3608 from finite_RAG show "finite (wRAG s)" |
|
3609 by (unfold RAG_split, auto) |
|
3610 qed |
|
3611 next |
|
3612 show "fbranch (hRAG s)" |
|
3613 proof(rule finite_fbranchI) |
|
3614 from finite_RAG |
|
3615 show "finite (hRAG s)" by (unfold RAG_split, auto) |
|
3616 qed |
|
3617 qed |
|
3618 moreover have "wf (tRAG s)" |
|
3619 proof(rule wf_subset) |
|
3620 show "wf (RAG s O RAG s)" using wf_RAG |
|
3621 by (fold wf_comp_self, simp) |
|
3622 next |
|
3623 show "tRAG s \<subseteq> (RAG s O RAG s)" |
|
3624 by (unfold tRAG_alt_def, auto) |
|
3625 qed |
|
3626 ultimately show ?thesis |
|
3627 by (unfold fsubtree_def fsubtree_axioms_def,auto) |
|
3628 qed |
|
3629 from this[folded tRAG_def] show "fsubtree (tRAG s)" . |
|
3630 qed |
|
3631 |
|
3632 lemma Max_UNION: |
|
3633 assumes "finite A" |
|
3634 and "A \<noteq> {}" |
|
3635 and "\<forall> M \<in> f ` A. finite M" |
|
3636 and "\<forall> M \<in> f ` A. M \<noteq> {}" |
|
3637 shows "Max (\<Union>x\<in> A. f x) = Max (Max ` f ` A)" (is "?L = ?R") |
|
3638 using assms[simp] |
|
3639 proof - |
|
3640 have "?L = Max (\<Union>(f ` A))" |
|
3641 by (fold Union_image_eq, simp) |
|
3642 also have "... = ?R" |
|
3643 by (subst Max_Union, simp+) |
|
3644 finally show ?thesis . |
|
3645 qed |
|
3646 |
|
3647 lemma max_Max_eq: |
|
3648 assumes "finite A" |
|
3649 and "A \<noteq> {}" |
|
3650 and "x = y" |
|
3651 shows "max x (Max A) = Max ({y} \<union> A)" (is "?L = ?R") |
|
3652 proof - |
|
3653 have "?R = Max (insert y A)" by simp |
|
3654 also from assms have "... = ?L" |
|
3655 by (subst Max.insert, simp+) |
|
3656 finally show ?thesis by simp |
|
3657 qed |
|
3658 |
|
3659 context valid_trace |
|
3660 begin |
|
3661 |
|
3662 (* ddd *) |
|
3663 lemma cp_gen_rec: |
|
3664 assumes "x = Th th" |
|
3665 shows "cp_gen s x = Max ({the_preced s th} \<union> (cp_gen s) ` children (tRAG s) x)" |
|
3666 proof(cases "children (tRAG s) x = {}") |
|
3667 case True |
|
3668 show ?thesis |
|
3669 by (unfold True cp_gen_def subtree_children, simp add:assms) |
|
3670 next |
|
3671 case False |
|
3672 hence [simp]: "children (tRAG s) x \<noteq> {}" by auto |
|
3673 note fsbttRAGs.finite_subtree[simp] |
|
3674 have [simp]: "finite (children (tRAG s) x)" |
|
3675 by (intro rev_finite_subset[OF fsbttRAGs.finite_subtree], |
|
3676 rule children_subtree) |
|
3677 { fix r x |
|
3678 have "subtree r x \<noteq> {}" by (auto simp:subtree_def) |
|
3679 } note this[simp] |
|
3680 have [simp]: "\<exists>x\<in>children (tRAG s) x. subtree (tRAG s) x \<noteq> {}" |
|
3681 proof - |
|
3682 from False obtain q where "q \<in> children (tRAG s) x" by blast |
|
3683 moreover have "subtree (tRAG s) q \<noteq> {}" by simp |
|
3684 ultimately show ?thesis by blast |
|
3685 qed |
|
3686 have h: "Max ((the_preced s \<circ> the_thread) ` |
|
3687 ({x} \<union> \<Union>(subtree (tRAG s) ` children (tRAG s) x))) = |
|
3688 Max ({the_preced s th} \<union> cp_gen s ` children (tRAG s) x)" |
|
3689 (is "?L = ?R") |
|
3690 proof - |
|
3691 let "Max (?f ` (?A \<union> \<Union> (?g ` ?B)))" = ?L |
|
3692 let "Max (_ \<union> (?h ` ?B))" = ?R |
|
3693 let ?L1 = "?f ` \<Union>(?g ` ?B)" |
|
3694 have eq_Max_L1: "Max ?L1 = Max (?h ` ?B)" |
|
3695 proof - |
|
3696 have "?L1 = ?f ` (\<Union> x \<in> ?B.(?g x))" by simp |
|
3697 also have "... = (\<Union> x \<in> ?B. ?f ` (?g x))" by auto |
|
3698 finally have "Max ?L1 = Max ..." by simp |
|
3699 also have "... = Max (Max ` (\<lambda>x. ?f ` subtree (tRAG s) x) ` ?B)" |
|
3700 by (subst Max_UNION, simp+) |
|
3701 also have "... = Max (cp_gen s ` children (tRAG s) x)" |
|
3702 by (unfold image_comp cp_gen_alt_def, simp) |
|
3703 finally show ?thesis . |
|
3704 qed |
|
3705 show ?thesis |
|
3706 proof - |
|
3707 have "?L = Max (?f ` ?A \<union> ?L1)" by simp |
|
3708 also have "... = max (the_preced s (the_thread x)) (Max ?L1)" |
|
3709 by (subst Max_Un, simp+) |
|
3710 also have "... = max (?f x) (Max (?h ` ?B))" |
|
3711 by (unfold eq_Max_L1, simp) |
|
3712 also have "... =?R" |
|
3713 by (rule max_Max_eq, (simp)+, unfold assms, simp) |
|
3714 finally show ?thesis . |
|
3715 qed |
|
3716 qed thus ?thesis |
|
3717 by (fold h subtree_children, unfold cp_gen_def, simp) |
|
3718 qed |
|
3719 |
|
3720 lemma cp_rec: |
|
3721 "cp s th = Max ({the_preced s th} \<union> |
|
3722 (cp s o the_thread) ` children (tRAG s) (Th th))" |
|
3723 proof - |
|
3724 have "Th th = Th th" by simp |
|
3725 note h = cp_gen_def_cond[OF this] cp_gen_rec[OF this] |
|
3726 show ?thesis |
|
3727 proof - |
|
3728 have "cp_gen s ` children (tRAG s) (Th th) = |
|
3729 (cp s \<circ> the_thread) ` children (tRAG s) (Th th)" |
|
3730 proof(rule cp_gen_over_set) |
|
3731 show " \<forall>x\<in>children (tRAG s) (Th th). \<exists>th. x = Th th" |
|
3732 by (unfold tRAG_alt_def, auto simp:children_def) |
|
3733 qed |
|
3734 thus ?thesis by (subst (1) h(1), unfold h(2), simp) |
|
3735 qed |
|
3736 qed |
|
3737 |
|
3738 end |
|
3739 |
|
3740 (* keep *) |
|
3741 lemma next_th_holding: |
|
3742 assumes vt: "vt s" |
|
3743 and nxt: "next_th s th cs th'" |
|
3744 shows "holding (wq s) th cs" |
|
3745 proof - |
|
3746 from nxt[unfolded next_th_def] |
|
3747 obtain rest where h: "wq s cs = th # rest" |
|
3748 "rest \<noteq> []" |
|
3749 "th' = hd (SOME q. distinct q \<and> set q = set rest)" by auto |
|
3750 thus ?thesis |
|
3751 by (unfold cs_holding_def, auto) |
|
3752 qed |
|
3753 |
|
3754 context valid_trace |
|
3755 begin |
|
3756 |
|
3757 lemma next_th_waiting: |
|
3758 assumes nxt: "next_th s th cs th'" |
|
3759 shows "waiting (wq s) th' cs" |
|
3760 proof - |
|
3761 from nxt[unfolded next_th_def] |
|
3762 obtain rest where h: "wq s cs = th # rest" |
|
3763 "rest \<noteq> []" |
|
3764 "th' = hd (SOME q. distinct q \<and> set q = set rest)" by auto |
|
3765 from wq_distinct[of cs, unfolded h] |
|
3766 have dst: "distinct (th # rest)" . |
|
3767 have in_rest: "th' \<in> set rest" |
|
3768 proof(unfold h, rule someI2) |
|
3769 show "distinct rest \<and> set rest = set rest" using dst by auto |
|
3770 next |
|
3771 fix x assume "distinct x \<and> set x = set rest" |
|
3772 with h(2) |
|
3773 show "hd x \<in> set (rest)" by (cases x, auto) |
|
3774 qed |
|
3775 hence "th' \<in> set (wq s cs)" by (unfold h(1), auto) |
|
3776 moreover have "th' \<noteq> hd (wq s cs)" |
|
3777 by (unfold h(1), insert in_rest dst, auto) |
|
3778 ultimately show ?thesis by (auto simp:cs_waiting_def) |
|
3779 qed |
|
3780 |
|
3781 lemma next_th_RAG: |
|
3782 assumes nxt: "next_th (s::event list) th cs th'" |
|
3783 shows "{(Cs cs, Th th), (Th th', Cs cs)} \<subseteq> RAG s" |
|
3784 using vt assms next_th_holding next_th_waiting |
|
3785 by (unfold s_RAG_def, simp) |
|
3786 |
|
3787 end |
|
3788 |
|
3789 |
|
3790 -- {* A useless definition *} |
|
3791 definition cps:: "state \<Rightarrow> (thread \<times> precedence) set" |
|
3792 where "cps s = {(th, cp s th) | th . th \<in> threads s}" |
|
3793 |
|
3794 end |
|