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Both sides previous revision Previous revision Next revision | Previous revision Next revision Both sides next revision | ||
sav08:compositional_vcg [2008/03/04 18:01] vkuncak |
sav08:compositional_vcg [2009/03/04 11:11] vkuncak |
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\[ | \[ | ||
F_c({\it assume}(e)) = (e \land \bigwedge_{v \in V} v=v') | F_c({\it assume}(e)) = (e \land \bigwedge_{v \in V} v=v') | ||
+ | \] | ||
+ | |||
+ | === Havoc === | ||
+ | |||
+ | \[ | ||
+ | F_c({\it havoc}(x)) = (\bigwedge_{v \in V \setminus\{x\}} v=v') | ||
\] | \] | ||
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\] | \] | ||
To avoid re-using variables, introduce always a fresh variable as //z//, denote it $z_i$. | To avoid re-using variables, introduce always a fresh variable as //z//, denote it $z_i$. | ||
+ | |||
===== Using Computed Formulas ===== | ===== Using Computed Formulas ===== | ||
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Using valid formulas we can move the existential quantifiers outside the formula. | Using valid formulas we can move the existential quantifiers outside the formula. | ||
+ | |||
+ | However, we can avoid expanding all paths and instead compute relations by following program structure. | ||
===== Size of Generated Formulas ===== | ===== Size of Generated Formulas ===== |