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sav08:normal_form_of_loop-free_programs [2008/03/04 17:32] vkuncak |
sav08:normal_form_of_loop-free_programs [2009/03/04 18:58] vkuncak |
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| \bigwedge_{i=1}^n (\{P\} p_i \{Q\}) | \bigwedge_{i=1}^n (\{P\} p_i \{Q\}) | ||
| \] | \] | ||
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| + | Note: the rule also applies to infinite union of paths (e.g. generated by loops). | ||
| ===== Three Approaches to Generate Verification Conditions ===== | ===== Three Approaches to Generate Verification Conditions ===== | ||
| Line 47: | Line 49: | ||
| - compute $sp(P,r)$ as a formula, then check entailment $sp(P,r) \subseteq Q$ (forward symbolic execution) | - compute $sp(P,r)$ as a formula, then check entailment $sp(P,r) \subseteq Q$ (forward symbolic execution) | ||
| - compute $wp(Q,r)$ as a formula, then check $P \subseteq wp(Q,r)$ (backward symbolic execution) | - compute $wp(Q,r)$ as a formula, then check $P \subseteq wp(Q,r)$ (backward symbolic execution) | ||
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