--- a/src/HOL/HoareParallel/RG_Examples.thy Thu Sep 17 14:17:37 2009 +1000
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,359 +0,0 @@
-header {* \section{Examples} *}
-
-theory RG_Examples
-imports RG_Syntax
-begin
-
-lemmas definitions [simp]= stable_def Pre_def Rely_def Guar_def Post_def Com_def
-
-subsection {* Set Elements of an Array to Zero *}
-
-lemma le_less_trans2: "\<lbrakk>(j::nat)<k; i\<le> j\<rbrakk> \<Longrightarrow> i<k"
-by simp
-
-lemma add_le_less_mono: "\<lbrakk> (a::nat) < c; b\<le>d \<rbrakk> \<Longrightarrow> a + b < c + d"
-by simp
-
-record Example1 =
- A :: "nat list"
-
-lemma Example1:
- "\<turnstile> COBEGIN
- SCHEME [0 \<le> i < n]
- (\<acute>A := \<acute>A [i := 0],
- \<lbrace> n < length \<acute>A \<rbrace>,
- \<lbrace> length \<ordmasculine>A = length \<ordfeminine>A \<and> \<ordmasculine>A ! i = \<ordfeminine>A ! i \<rbrace>,
- \<lbrace> length \<ordmasculine>A = length \<ordfeminine>A \<and> (\<forall>j<n. i \<noteq> j \<longrightarrow> \<ordmasculine>A ! j = \<ordfeminine>A ! j) \<rbrace>,
- \<lbrace> \<acute>A ! i = 0 \<rbrace>)
- COEND
- SAT [\<lbrace> n < length \<acute>A \<rbrace>, \<lbrace> \<ordmasculine>A = \<ordfeminine>A \<rbrace>, \<lbrace> True \<rbrace>, \<lbrace> \<forall>i < n. \<acute>A ! i = 0 \<rbrace>]"
-apply(rule Parallel)
-apply (auto intro!: Basic)
-done
-
-lemma Example1_parameterized:
-"k < t \<Longrightarrow>
- \<turnstile> COBEGIN
- SCHEME [k*n\<le>i<(Suc k)*n] (\<acute>A:=\<acute>A[i:=0],
- \<lbrace>t*n < length \<acute>A\<rbrace>,
- \<lbrace>t*n < length \<ordmasculine>A \<and> length \<ordmasculine>A=length \<ordfeminine>A \<and> \<ordmasculine>A!i = \<ordfeminine>A!i\<rbrace>,
- \<lbrace>t*n < length \<ordmasculine>A \<and> length \<ordmasculine>A=length \<ordfeminine>A \<and> (\<forall>j<length \<ordmasculine>A . i\<noteq>j \<longrightarrow> \<ordmasculine>A!j = \<ordfeminine>A!j)\<rbrace>,
- \<lbrace>\<acute>A!i=0\<rbrace>)
- COEND
- SAT [\<lbrace>t*n < length \<acute>A\<rbrace>,
- \<lbrace>t*n < length \<ordmasculine>A \<and> length \<ordmasculine>A=length \<ordfeminine>A \<and> (\<forall>i<n. \<ordmasculine>A!(k*n+i)=\<ordfeminine>A!(k*n+i))\<rbrace>,
- \<lbrace>t*n < length \<ordmasculine>A \<and> length \<ordmasculine>A=length \<ordfeminine>A \<and>
- (\<forall>i<length \<ordmasculine>A . (i<k*n \<longrightarrow> \<ordmasculine>A!i = \<ordfeminine>A!i) \<and> ((Suc k)*n \<le> i\<longrightarrow> \<ordmasculine>A!i = \<ordfeminine>A!i))\<rbrace>,
- \<lbrace>\<forall>i<n. \<acute>A!(k*n+i) = 0\<rbrace>]"
-apply(rule Parallel)
- apply auto
- apply(erule_tac x="k*n +i" in allE)
- apply(subgoal_tac "k*n+i <length (A b)")
- apply force
- apply(erule le_less_trans2)
- apply(case_tac t,simp+)
- apply (simp add:add_commute)
- apply(simp add: add_le_mono)
-apply(rule Basic)
- apply simp
- apply clarify
- apply (subgoal_tac "k*n+i< length (A x)")
- apply simp
- apply(erule le_less_trans2)
- apply(case_tac t,simp+)
- apply (simp add:add_commute)
- apply(rule add_le_mono, auto)
-done
-
-
-subsection {* Increment a Variable in Parallel *}
-
-subsubsection {* Two components *}
-
-record Example2 =
- x :: nat
- c_0 :: nat
- c_1 :: nat
-
-lemma Example2:
- "\<turnstile> COBEGIN
- (\<langle> \<acute>x:=\<acute>x+1;; \<acute>c_0:=\<acute>c_0 + 1 \<rangle>,
- \<lbrace>\<acute>x=\<acute>c_0 + \<acute>c_1 \<and> \<acute>c_0=0\<rbrace>,
- \<lbrace>\<ordmasculine>c_0 = \<ordfeminine>c_0 \<and>
- (\<ordmasculine>x=\<ordmasculine>c_0 + \<ordmasculine>c_1
- \<longrightarrow> \<ordfeminine>x = \<ordfeminine>c_0 + \<ordfeminine>c_1)\<rbrace>,
- \<lbrace>\<ordmasculine>c_1 = \<ordfeminine>c_1 \<and>
- (\<ordmasculine>x=\<ordmasculine>c_0 + \<ordmasculine>c_1
- \<longrightarrow> \<ordfeminine>x =\<ordfeminine>c_0 + \<ordfeminine>c_1)\<rbrace>,
- \<lbrace>\<acute>x=\<acute>c_0 + \<acute>c_1 \<and> \<acute>c_0=1 \<rbrace>)
- \<parallel>
- (\<langle> \<acute>x:=\<acute>x+1;; \<acute>c_1:=\<acute>c_1+1 \<rangle>,
- \<lbrace>\<acute>x=\<acute>c_0 + \<acute>c_1 \<and> \<acute>c_1=0 \<rbrace>,
- \<lbrace>\<ordmasculine>c_1 = \<ordfeminine>c_1 \<and>
- (\<ordmasculine>x=\<ordmasculine>c_0 + \<ordmasculine>c_1
- \<longrightarrow> \<ordfeminine>x = \<ordfeminine>c_0 + \<ordfeminine>c_1)\<rbrace>,
- \<lbrace>\<ordmasculine>c_0 = \<ordfeminine>c_0 \<and>
- (\<ordmasculine>x=\<ordmasculine>c_0 + \<ordmasculine>c_1
- \<longrightarrow> \<ordfeminine>x =\<ordfeminine>c_0 + \<ordfeminine>c_1)\<rbrace>,
- \<lbrace>\<acute>x=\<acute>c_0 + \<acute>c_1 \<and> \<acute>c_1=1\<rbrace>)
- COEND
- SAT [\<lbrace>\<acute>x=0 \<and> \<acute>c_0=0 \<and> \<acute>c_1=0\<rbrace>,
- \<lbrace>\<ordmasculine>x=\<ordfeminine>x \<and> \<ordmasculine>c_0= \<ordfeminine>c_0 \<and> \<ordmasculine>c_1=\<ordfeminine>c_1\<rbrace>,
- \<lbrace>True\<rbrace>,
- \<lbrace>\<acute>x=2\<rbrace>]"
-apply(rule Parallel)
- apply simp_all
- apply clarify
- apply(case_tac i)
- apply simp
- apply(rule conjI)
- apply clarify
- apply simp
- apply clarify
- apply simp
- apply(case_tac j,simp)
- apply simp
- apply simp
- apply(rule conjI)
- apply clarify
- apply simp
- apply clarify
- apply simp
- apply(subgoal_tac "j=0")
- apply (rotate_tac -1)
- apply (simp (asm_lr))
- apply arith
- apply clarify
- apply(case_tac i,simp,simp)
- apply clarify
- apply simp
- apply(erule_tac x=0 in all_dupE)
- apply(erule_tac x=1 in allE,simp)
-apply clarify
-apply(case_tac i,simp)
- apply(rule Await)
- apply simp_all
- apply(clarify)
- apply(rule Seq)
- prefer 2
- apply(rule Basic)
- apply simp_all
- apply(rule subset_refl)
- apply(rule Basic)
- apply simp_all
- apply clarify
- apply simp
-apply(rule Await)
- apply simp_all
-apply(clarify)
-apply(rule Seq)
- prefer 2
- apply(rule Basic)
- apply simp_all
- apply(rule subset_refl)
-apply(auto intro!: Basic)
-done
-
-subsubsection {* Parameterized *}
-
-lemma Example2_lemma2_aux: "j<n \<Longrightarrow>
- (\<Sum>i=0..<n. (b i::nat)) =
- (\<Sum>i=0..<j. b i) + b j + (\<Sum>i=0..<n-(Suc j) . b (Suc j + i))"
-apply(induct n)
- apply simp_all
-apply(simp add:less_Suc_eq)
- apply(auto)
-apply(subgoal_tac "n - j = Suc(n- Suc j)")
- apply simp
-apply arith
-done
-
-lemma Example2_lemma2_aux2:
- "j\<le> s \<Longrightarrow> (\<Sum>i::nat=0..<j. (b (s:=t)) i) = (\<Sum>i=0..<j. b i)"
-apply(induct j)
- apply (simp_all cong:setsum_cong)
-done
-
-lemma Example2_lemma2:
- "\<lbrakk>j<n; b j=0\<rbrakk> \<Longrightarrow> Suc (\<Sum>i::nat=0..<n. b i)=(\<Sum>i=0..<n. (b (j := Suc 0)) i)"
-apply(frule_tac b="(b (j:=(Suc 0)))" in Example2_lemma2_aux)
-apply(erule_tac t="setsum (b(j := (Suc 0))) {0..<n}" in ssubst)
-apply(frule_tac b=b in Example2_lemma2_aux)
-apply(erule_tac t="setsum b {0..<n}" in ssubst)
-apply(subgoal_tac "Suc (setsum b {0..<j} + b j + (\<Sum>i=0..<n - Suc j. b (Suc j + i)))=(setsum b {0..<j} + Suc (b j) + (\<Sum>i=0..<n - Suc j. b (Suc j + i)))")
-apply(rotate_tac -1)
-apply(erule ssubst)
-apply(subgoal_tac "j\<le>j")
- apply(drule_tac b="b" and t="(Suc 0)" in Example2_lemma2_aux2)
-apply(rotate_tac -1)
-apply(erule ssubst)
-apply simp_all
-done
-
-lemma Example2_lemma2_Suc0: "\<lbrakk>j<n; b j=0\<rbrakk> \<Longrightarrow>
- Suc (\<Sum>i::nat=0..< n. b i)=(\<Sum>i=0..< n. (b (j:=Suc 0)) i)"
-by(simp add:Example2_lemma2)
-
-record Example2_parameterized =
- C :: "nat \<Rightarrow> nat"
- y :: nat
-
-lemma Example2_parameterized: "0<n \<Longrightarrow>
- \<turnstile> COBEGIN SCHEME [0\<le>i<n]
- (\<langle> \<acute>y:=\<acute>y+1;; \<acute>C:=\<acute>C (i:=1) \<rangle>,
- \<lbrace>\<acute>y=(\<Sum>i=0..<n. \<acute>C i) \<and> \<acute>C i=0\<rbrace>,
- \<lbrace>\<ordmasculine>C i = \<ordfeminine>C i \<and>
- (\<ordmasculine>y=(\<Sum>i=0..<n. \<ordmasculine>C i) \<longrightarrow> \<ordfeminine>y =(\<Sum>i=0..<n. \<ordfeminine>C i))\<rbrace>,
- \<lbrace>(\<forall>j<n. i\<noteq>j \<longrightarrow> \<ordmasculine>C j = \<ordfeminine>C j) \<and>
- (\<ordmasculine>y=(\<Sum>i=0..<n. \<ordmasculine>C i) \<longrightarrow> \<ordfeminine>y =(\<Sum>i=0..<n. \<ordfeminine>C i))\<rbrace>,
- \<lbrace>\<acute>y=(\<Sum>i=0..<n. \<acute>C i) \<and> \<acute>C i=1\<rbrace>)
- COEND
- SAT [\<lbrace>\<acute>y=0 \<and> (\<Sum>i=0..<n. \<acute>C i)=0 \<rbrace>, \<lbrace>\<ordmasculine>C=\<ordfeminine>C \<and> \<ordmasculine>y=\<ordfeminine>y\<rbrace>, \<lbrace>True\<rbrace>, \<lbrace>\<acute>y=n\<rbrace>]"
-apply(rule Parallel)
-apply force
-apply force
-apply(force)
-apply clarify
-apply simp
-apply(simp cong:setsum_ivl_cong)
-apply clarify
-apply simp
-apply(rule Await)
-apply simp_all
-apply clarify
-apply(rule Seq)
-prefer 2
-apply(rule Basic)
-apply(rule subset_refl)
-apply simp+
-apply(rule Basic)
-apply simp
-apply clarify
-apply simp
-apply(simp add:Example2_lemma2_Suc0 cong:if_cong)
-apply simp+
-done
-
-subsection {* Find Least Element *}
-
-text {* A previous lemma: *}
-
-lemma mod_aux :"\<lbrakk>i < (n::nat); a mod n = i; j < a + n; j mod n = i; a < j\<rbrakk> \<Longrightarrow> False"
-apply(subgoal_tac "a=a div n*n + a mod n" )
- prefer 2 apply (simp (no_asm_use))
-apply(subgoal_tac "j=j div n*n + j mod n")
- prefer 2 apply (simp (no_asm_use))
-apply simp
-apply(subgoal_tac "a div n*n < j div n*n")
-prefer 2 apply arith
-apply(subgoal_tac "j div n*n < (a div n + 1)*n")
-prefer 2 apply simp
-apply (simp only:mult_less_cancel2)
-apply arith
-done
-
-record Example3 =
- X :: "nat \<Rightarrow> nat"
- Y :: "nat \<Rightarrow> nat"
-
-lemma Example3: "m mod n=0 \<Longrightarrow>
- \<turnstile> COBEGIN
- SCHEME [0\<le>i<n]
- (WHILE (\<forall>j<n. \<acute>X i < \<acute>Y j) DO
- IF P(B!(\<acute>X i)) THEN \<acute>Y:=\<acute>Y (i:=\<acute>X i)
- ELSE \<acute>X:= \<acute>X (i:=(\<acute>X i)+ n) FI
- OD,
- \<lbrace>(\<acute>X i) mod n=i \<and> (\<forall>j<\<acute>X i. j mod n=i \<longrightarrow> \<not>P(B!j)) \<and> (\<acute>Y i<m \<longrightarrow> P(B!(\<acute>Y i)) \<and> \<acute>Y i\<le> m+i)\<rbrace>,
- \<lbrace>(\<forall>j<n. i\<noteq>j \<longrightarrow> \<ordfeminine>Y j \<le> \<ordmasculine>Y j) \<and> \<ordmasculine>X i = \<ordfeminine>X i \<and>
- \<ordmasculine>Y i = \<ordfeminine>Y i\<rbrace>,
- \<lbrace>(\<forall>j<n. i\<noteq>j \<longrightarrow> \<ordmasculine>X j = \<ordfeminine>X j \<and> \<ordmasculine>Y j = \<ordfeminine>Y j) \<and>
- \<ordfeminine>Y i \<le> \<ordmasculine>Y i\<rbrace>,
- \<lbrace>(\<acute>X i) mod n=i \<and> (\<forall>j<\<acute>X i. j mod n=i \<longrightarrow> \<not>P(B!j)) \<and> (\<acute>Y i<m \<longrightarrow> P(B!(\<acute>Y i)) \<and> \<acute>Y i\<le> m+i) \<and> (\<exists>j<n. \<acute>Y j \<le> \<acute>X i) \<rbrace>)
- COEND
- SAT [\<lbrace> \<forall>i<n. \<acute>X i=i \<and> \<acute>Y i=m+i \<rbrace>,\<lbrace>\<ordmasculine>X=\<ordfeminine>X \<and> \<ordmasculine>Y=\<ordfeminine>Y\<rbrace>,\<lbrace>True\<rbrace>,
- \<lbrace>\<forall>i<n. (\<acute>X i) mod n=i \<and> (\<forall>j<\<acute>X i. j mod n=i \<longrightarrow> \<not>P(B!j)) \<and>
- (\<acute>Y i<m \<longrightarrow> P(B!(\<acute>Y i)) \<and> \<acute>Y i\<le> m+i) \<and> (\<exists>j<n. \<acute>Y j \<le> \<acute>X i)\<rbrace>]"
-apply(rule Parallel)
---{*5 subgoals left *}
-apply force+
-apply clarify
-apply simp
-apply(rule While)
- apply force
- apply force
- apply force
- apply(rule_tac pre'="\<lbrace> \<acute>X i mod n = i \<and> (\<forall>j. j<\<acute>X i \<longrightarrow> j mod n = i \<longrightarrow> \<not>P(B!j)) \<and> (\<acute>Y i < n * q \<longrightarrow> P (B!(\<acute>Y i))) \<and> \<acute>X i<\<acute>Y i\<rbrace>" in Conseq)
- apply force
- apply(rule subset_refl)+
- apply(rule Cond)
- apply force
- apply(rule Basic)
- apply force
- apply fastsimp
- apply force
- apply force
- apply(rule Basic)
- apply simp
- apply clarify
- apply simp
- apply (case_tac "X x (j mod n) \<le> j")
- apply (drule le_imp_less_or_eq)
- apply (erule disjE)
- apply (drule_tac j=j and n=n and i="j mod n" and a="X x (j mod n)" in mod_aux)
- apply auto
-done
-
-text {* Same but with a list as auxiliary variable: *}
-
-record Example3_list =
- X :: "nat list"
- Y :: "nat list"
-
-lemma Example3_list: "m mod n=0 \<Longrightarrow> \<turnstile> (COBEGIN SCHEME [0\<le>i<n]
- (WHILE (\<forall>j<n. \<acute>X!i < \<acute>Y!j) DO
- IF P(B!(\<acute>X!i)) THEN \<acute>Y:=\<acute>Y[i:=\<acute>X!i] ELSE \<acute>X:= \<acute>X[i:=(\<acute>X!i)+ n] FI
- OD,
- \<lbrace>n<length \<acute>X \<and> n<length \<acute>Y \<and> (\<acute>X!i) mod n=i \<and> (\<forall>j<\<acute>X!i. j mod n=i \<longrightarrow> \<not>P(B!j)) \<and> (\<acute>Y!i<m \<longrightarrow> P(B!(\<acute>Y!i)) \<and> \<acute>Y!i\<le> m+i)\<rbrace>,
- \<lbrace>(\<forall>j<n. i\<noteq>j \<longrightarrow> \<ordfeminine>Y!j \<le> \<ordmasculine>Y!j) \<and> \<ordmasculine>X!i = \<ordfeminine>X!i \<and>
- \<ordmasculine>Y!i = \<ordfeminine>Y!i \<and> length \<ordmasculine>X = length \<ordfeminine>X \<and> length \<ordmasculine>Y = length \<ordfeminine>Y\<rbrace>,
- \<lbrace>(\<forall>j<n. i\<noteq>j \<longrightarrow> \<ordmasculine>X!j = \<ordfeminine>X!j \<and> \<ordmasculine>Y!j = \<ordfeminine>Y!j) \<and>
- \<ordfeminine>Y!i \<le> \<ordmasculine>Y!i \<and> length \<ordmasculine>X = length \<ordfeminine>X \<and> length \<ordmasculine>Y = length \<ordfeminine>Y\<rbrace>,
- \<lbrace>(\<acute>X!i) mod n=i \<and> (\<forall>j<\<acute>X!i. j mod n=i \<longrightarrow> \<not>P(B!j)) \<and> (\<acute>Y!i<m \<longrightarrow> P(B!(\<acute>Y!i)) \<and> \<acute>Y!i\<le> m+i) \<and> (\<exists>j<n. \<acute>Y!j \<le> \<acute>X!i) \<rbrace>) COEND)
- SAT [\<lbrace>n<length \<acute>X \<and> n<length \<acute>Y \<and> (\<forall>i<n. \<acute>X!i=i \<and> \<acute>Y!i=m+i) \<rbrace>,
- \<lbrace>\<ordmasculine>X=\<ordfeminine>X \<and> \<ordmasculine>Y=\<ordfeminine>Y\<rbrace>,
- \<lbrace>True\<rbrace>,
- \<lbrace>\<forall>i<n. (\<acute>X!i) mod n=i \<and> (\<forall>j<\<acute>X!i. j mod n=i \<longrightarrow> \<not>P(B!j)) \<and>
- (\<acute>Y!i<m \<longrightarrow> P(B!(\<acute>Y!i)) \<and> \<acute>Y!i\<le> m+i) \<and> (\<exists>j<n. \<acute>Y!j \<le> \<acute>X!i)\<rbrace>]"
-apply(rule Parallel)
---{* 5 subgoals left *}
-apply force+
-apply clarify
-apply simp
-apply(rule While)
- apply force
- apply force
- apply force
- apply(rule_tac pre'="\<lbrace>n<length \<acute>X \<and> n<length \<acute>Y \<and> \<acute>X ! i mod n = i \<and> (\<forall>j. j < \<acute>X ! i \<longrightarrow> j mod n = i \<longrightarrow> \<not> P (B ! j)) \<and> (\<acute>Y ! i < n * q \<longrightarrow> P (B ! (\<acute>Y ! i))) \<and> \<acute>X!i<\<acute>Y!i\<rbrace>" in Conseq)
- apply force
- apply(rule subset_refl)+
- apply(rule Cond)
- apply force
- apply(rule Basic)
- apply force
- apply force
- apply force
- apply force
- apply(rule Basic)
- apply simp
- apply clarify
- apply simp
- apply(rule allI)
- apply(rule impI)+
- apply(case_tac "X x ! i\<le> j")
- apply(drule le_imp_less_or_eq)
- apply(erule disjE)
- apply(drule_tac j=j and n=n and i=i and a="X x ! i" in mod_aux)
- apply auto
-done
-
-end