1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
|
/*******************************************************************\
Module: Unit tests for variable/sensitivity/abstract_object::merge
Author: DiffBlue Limited
\*******************************************************************/
#include <testing-utils/use_catch.h>
#include <util/arith_tools.h>
#include <util/bitvector_types.h>
#include <util/interval.h>
#include <util/namespace.h>
#include <util/symbol_table.h>
#define V(X) (bvrep2integer(X.get(ID_value).c_str(), 32, true))
#define V_(X) (bvrep2integer(X.c_str(), 32, true))
#define CEV(X) (from_integer(mp_integer(X), signedbv_typet(32)))
SCENARIO("subtract interval domain", "[core][analyses][interval][subtract]")
{
GIVEN("Two simple signed intervals")
{
symbol_tablet symbol_table;
namespacet ns(symbol_table);
WHEN("The result is positive [6,8]-[2,4]")
{
constant_interval_exprt left(CEV(6), CEV(8));
constant_interval_exprt right(CEV(2), CEV(4));
constant_interval_exprt result =
constant_interval_exprt::minus(left, right);
THEN("Domain is consistent")
{
REQUIRE(V(left.get_lower()) == 6);
REQUIRE(V(left.get_upper()) == 8);
REQUIRE(V(right.get_lower()) == 2);
REQUIRE(V(right.get_upper()) == 4);
}
THEN("The result is [2, 6]")
{
REQUIRE(V(result.get_lower()) == 2);
REQUIRE(V(result.get_upper()) == 6);
}
}
WHEN("One contains infinite [2,4]-[6,INF]")
{
constant_interval_exprt left(CEV(2), CEV(4));
constant_interval_exprt right(
CEV(6), max_value_exprt(signedbv_typet(32)));
constant_interval_exprt result =
constant_interval_exprt::minus(left, right);
THEN("Domain is consistent")
{
REQUIRE(V(left.get_lower()) == 2);
REQUIRE(V(left.get_upper()) == 4);
REQUIRE(V(right.get_lower()) == 6);
REQUIRE(right.has_no_upper_bound());
}
CAPTURE(result);
THEN("The result is [MIN, -2]")
{
REQUIRE(V(result.get_upper()) == -2);
REQUIRE(result.has_no_lower_bound());
}
}
WHEN("Both contain infinite [2,INF]-[6,INF]")
{
constant_interval_exprt left(CEV(2), max_value_exprt(signedbv_typet(32)));
constant_interval_exprt right(
CEV(6), max_value_exprt(signedbv_typet(32)));
constant_interval_exprt result =
constant_interval_exprt::minus(left, right);
THEN("Domain is consistent")
{
REQUIRE(V(left.get_lower()) == 2);
REQUIRE(left.has_no_upper_bound());
REQUIRE(V(right.get_lower()) == 6);
REQUIRE(right.has_no_upper_bound());
}
CAPTURE(result);
THEN("The result is [MIN, MAX]")
{
REQUIRE(result.has_no_upper_bound());
REQUIRE(result.has_no_lower_bound());
}
}
}
}
SCENARIO(
"Subtracting unsigned integers",
"[core][analyses][interval][subtract]")
{
auto get_value = [](int x) { return from_integer(x, signedbv_typet(32)); };
WHEN("Subtracting two constant intervals")
{
auto lhs = constant_interval_exprt::singleton(get_value(10));
auto rhs = constant_interval_exprt::singleton(get_value(3));
THEN("it should work")
{
auto result = constant_interval_exprt::minus(lhs, rhs);
REQUIRE(result.is_single_value_interval());
auto maybe_lower = numeric_cast<mp_integer>(result.get_lower());
REQUIRE(maybe_lower.has_value());
REQUIRE(maybe_lower.value() == 7);
}
}
WHEN("Subtracting zero from something")
{
auto lhs = constant_interval_exprt::singleton(get_value(10));
auto rhs = constant_interval_exprt::singleton(get_value(0));
THEN("it should not give a completely crazy result")
{
auto result = constant_interval_exprt::minus(lhs, rhs);
REQUIRE(result.is_single_value_interval());
auto maybe_lower = numeric_cast<mp_integer>(result.get_lower());
REQUIRE(maybe_lower.has_value());
REQUIRE(maybe_lower.value() == 10);
}
}
WHEN("Subtracting an non-constant interval containing zero")
{
auto lhs = constant_interval_exprt::singleton(get_value(10));
auto rhs = constant_interval_exprt(get_value(0), get_value(1));
THEN("it should not give a completely crazy result")
{
auto result = constant_interval_exprt::minus(lhs, rhs);
auto maybe_lower = numeric_cast<mp_integer>(result.get_lower());
REQUIRE(maybe_lower.has_value());
REQUIRE(maybe_lower.value() == 9);
auto maybe_upper = numeric_cast<mp_integer>(result.get_upper());
REQUIRE(maybe_upper.has_value());
REQUIRE(maybe_upper.value() == 10);
}
}
}
|
