(* Author: Tobias Nipkow *)
theory Abs_Int1_const
imports Abs_Int1
begin
subsection "Constant Propagation"
datatype const = Const val | Any
fun \<gamma>_const where
"\<gamma>_const (Const n) = {n}" |
"\<gamma>_const (Any) = UNIV"
fun plus_const where
"plus_const (Const m) (Const n) = Const(m+n)" |
"plus_const _ _ = Any"
lemma plus_const_cases: "plus_const a1 a2 =
(case (a1,a2) of (Const m, Const n) \<Rightarrow> Const(m+n) | _ \<Rightarrow> Any)"
by(auto split: prod.split const.split)
instantiation const :: semilattice
begin
fun less_eq_const where
"_ \<le> Any = True" |
"Const n \<le> Const m = (n=m)" |
"Any \<le> Const _ = False"
definition "a < (b::const) = (a \<le> b & ~ b \<le> a)"
fun join_const where
"Const m \<squnion> Const n = (if n=m then Const m else Any)" |
"_ \<squnion> _ = Any"
definition "\<top> = Any"
instance
proof
case goal1 thus ?case by (rule less_const_def)
next
case goal2 show ?case by (cases x) simp_all
next
case goal3 thus ?case by(cases z, cases y, cases x, simp_all)
next
case goal4 thus ?case by(cases x, cases y, simp_all, cases y, simp_all)
next
case goal6 thus ?case by(cases x, cases y, simp_all)
next
case goal7 thus ?case by(cases y, cases x, simp_all)
next
case goal8 thus ?case by(cases z, cases y, cases x, simp_all)
next
case goal5 thus ?case by(simp add: top_const_def)
qed
end
interpretation Val_abs
where \<gamma> = \<gamma>_const and num' = Const and plus' = plus_const
proof
case goal1 thus ?case
by(cases a, cases b, simp, simp, cases b, simp, simp)
next
case goal2 show ?case by(simp add: top_const_def)
next
case goal3 show ?case by simp
next
case goal4 thus ?case
by(auto simp: plus_const_cases split: const.split)
qed
interpretation Abs_Int
where \<gamma> = \<gamma>_const and num' = Const and plus' = plus_const
defines AI_const is AI and step_const is step' and aval'_const is aval'
..
subsubsection "Tests"
definition "steps c i = (step_const(Top(vars c)) ^^ i) (bot c)"
value "show_acom (steps test1_const 0)"
value "show_acom (steps test1_const 1)"
value "show_acom (steps test1_const 2)"
value "show_acom (steps test1_const 3)"
value "show_acom (the(AI_const test1_const))"
value "show_acom (the(AI_const test2_const))"
value "show_acom (the(AI_const test3_const))"
value "show_acom (steps test4_const 0)"
value "show_acom (steps test4_const 1)"
value "show_acom (steps test4_const 2)"
value "show_acom (steps test4_const 3)"
value "show_acom (steps test4_const 4)"
value "show_acom (the(AI_const test4_const))"
value "show_acom (steps test5_const 0)"
value "show_acom (steps test5_const 1)"
value "show_acom (steps test5_const 2)"
value "show_acom (steps test5_const 3)"
value "show_acom (steps test5_const 4)"
value "show_acom (steps test5_const 5)"
value "show_acom (steps test5_const 6)"
value "show_acom (the(AI_const test5_const))"
value "show_acom (steps test6_const 0)"
value "show_acom (steps test6_const 1)"
value "show_acom (steps test6_const 2)"
value "show_acom (steps test6_const 3)"
value "show_acom (steps test6_const 4)"
value "show_acom (steps test6_const 5)"
value "show_acom (steps test6_const 6)"
value "show_acom (steps test6_const 7)"
value "show_acom (steps test6_const 8)"
value "show_acom (steps test6_const 9)"
value "show_acom (steps test6_const 10)"
value "show_acom (steps test6_const 11)"
value "show_acom (steps test6_const 12)"
value "show_acom (steps test6_const 13)"
value "show_acom (the(AI_const test6_const))"
text{* Monotonicity: *}
interpretation Abs_Int_mono
where \<gamma> = \<gamma>_const and num' = Const and plus' = plus_const
proof
case goal1 thus ?case
by(auto simp: plus_const_cases split: const.split)
qed
text{* Termination: *}
definition "m_const x = (case x of Const _ \<Rightarrow> 1 | Any \<Rightarrow> 0)"
interpretation Abs_Int_measure
where \<gamma> = \<gamma>_const and num' = Const and plus' = plus_const
and m = m_const and h = "1"
proof
case goal1 thus ?case by(auto simp: m_const_def split: const.splits)
next
case goal2 thus ?case by(auto simp: m_const_def less_const_def split: const.splits)
qed
thm AI_Some_measure
end