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guard_bdd.cpp
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1/*******************************************************************\
2
3Module: Guard Data Structure
4
5Author: Romain Brenguier, romain.brenguier@diffblue.com
6
7\*******************************************************************/
8
11
12#include "guard_bdd.h"
13
15#include <util/expr_util.h>
16#include <util/invariant.h>
17#include <util/std_expr.h>
18
20 : manager(manager), bdd(manager.from_expr(e))
21{
22}
23
25{
26 PRECONDITION(&manager == &other.manager);
27 bdd = other.bdd;
28 return *this;
29}
30
32{
33 PRECONDITION(&manager == &other.manager);
34 std::swap(bdd, other.bdd);
35 return *this;
36}
37
39{
40 if(is_true())
41 {
42 // do nothing
43 return expr;
44 }
45 else
46 {
47 if(expr.is_false())
48 {
49 return boolean_negate(as_expr());
50 }
51 else
52 {
53 return implies_exprt{as_expr(), expr};
54 }
55 }
56}
57
59{
60 bdd = bdd.bdd_and(guard.bdd);
61 return *this;
62}
63
65{
67 return *this;
68}
69
71{
72 g1.bdd = g1.bdd.constrain(g2.bdd.bdd_or(g1.bdd));
73 return g1;
74}
75
77{
78 g1.bdd = g1.bdd.bdd_or(g2.bdd);
79 return g1;
80}
81
83{
84 return manager.as_expr(bdd);
85}
Conversion between exprt and miniBDD.
static exprt guard(const exprt::operandst &guards, exprt cond)
ait supplies three of the four components needed: an abstract interpreter (in this case handling func...
Definition ai.h:562
Conversion between exprt and bbdt This encapsulate a bdd_managert, thus BDDs created with this class ...
Definition bdd_expr.h:34
exprt as_expr(const bddt &root) const
Definition bdd_expr.cpp:171
bddt from_expr(const exprt &expr)
Definition bdd_expr.cpp:87
bddt bdd_and(const bddt &other) const
Definition bdd_cudd.h:105
BDD bdd
Definition bdd_cudd.h:128
Base class for all expressions.
Definition expr.h:56
bool is_false() const
Return whether the expression is a constant representing false.
Definition expr.cpp:34
bool is_true() const
Definition guard_bdd.h:44
exprt as_expr() const
Definition guard_bdd.cpp:82
guard_bddt & add(const exprt &expr)
Definition guard_bdd.cpp:64
guard_bddt(const exprt &e, bdd_exprt &manager)
Definition guard_bdd.cpp:19
guard_bddt & append(const guard_bddt &guard)
Definition guard_bdd.cpp:58
exprt guard_expr(exprt expr) const
Return guard => dest or a simplified variant thereof if either guard or dest are trivial.
Definition guard_bdd.cpp:38
bdd_exprt & manager
Definition guard_bdd.h:73
guard_bddt & operator=(const guard_bddt &other)
Definition guard_bdd.cpp:24
Boolean implication.
Definition std_expr.h:2225
exprt boolean_negate(const exprt &src)
negate a Boolean expression, possibly removing a not_exprt, and swapping false and true
Deprecated expression utility functions.
guard_bddt & operator|=(guard_bddt &g1, const guard_bddt &g2)
Definition guard_bdd.cpp:76
guard_bddt & operator-=(guard_bddt &g1, const guard_bddt &g2)
Definition guard_bdd.cpp:70
Guard Data Structure Implementation using BDDs.
std::string from_expr(const namespacet &ns, const irep_idt &identifier, const exprt &expr)
#define PRECONDITION(CONDITION)
Definition invariant.h:463
API to expression classes.