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
153
154
155
156
157
158
159
160
161
162
163
164
|
//===-- SeedInfo.cpp ------------------------------------------------------===//
//
// The KLEE Symbolic Virtual Machine
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "Memory.h"
#include "SeedInfo.h"
#include "TimingSolver.h"
#include "klee/ExecutionState.h"
#include "klee/Expr/Expr.h"
#include "klee/Expr/ExprUtil.h"
#include "klee/Internal/ADT/KTest.h"
#include "klee/Internal/Support/ErrorHandling.h"
using namespace klee;
KTestObject *SeedInfo::getNextInput(const MemoryObject *mo,
bool byName) {
if (byName) {
unsigned i;
for (i=0; i<input->numObjects; ++i) {
KTestObject *obj = &input->objects[i];
if (std::string(obj->name) == mo->name)
if (used.insert(obj).second)
return obj;
}
// If first unused input matches in size then accept that as
// well.
for (i=0; i<input->numObjects; ++i)
if (!used.count(&input->objects[i]))
break;
if (i<input->numObjects) {
KTestObject *obj = &input->objects[i];
if (obj->numBytes == mo->size) {
used.insert(obj);
klee_warning_once(mo, "using seed input %s[%d] for: %s (no name match)",
obj->name, obj->numBytes, mo->name.c_str());
return obj;
}
}
klee_warning_once(mo, "no seed input for: %s", mo->name.c_str());
return 0;
} else {
if (inputPosition >= input->numObjects) {
return 0;
} else {
return &input->objects[inputPosition++];
}
}
}
void SeedInfo::patchSeed(const ExecutionState &state,
ref<Expr> condition,
TimingSolver *solver) {
std::vector< ref<Expr> > required(state.constraints.begin(),
state.constraints.end());
ExecutionState tmp(required);
tmp.addConstraint(condition);
// Try and patch direct reads first, this is likely to resolve the
// problem quickly and avoids long traversal of all seed
// values. There are other smart ways to do this, the nicest is if
// we got a minimal counterexample from STP, in which case we would
// just inject those values back into the seed.
std::set< std::pair<const Array*, unsigned> > directReads;
std::vector< ref<ReadExpr> > reads;
findReads(condition, false, reads);
for (std::vector< ref<ReadExpr> >::iterator it = reads.begin(),
ie = reads.end(); it != ie; ++it) {
ReadExpr *re = it->get();
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(re->index)) {
directReads.insert(std::make_pair(re->updates.root,
(unsigned) CE->getZExtValue(32)));
}
}
for (std::set< std::pair<const Array*, unsigned> >::iterator
it = directReads.begin(), ie = directReads.end(); it != ie; ++it) {
const Array *array = it->first;
unsigned i = it->second;
ref<Expr> read = ReadExpr::create(UpdateList(array, 0),
ConstantExpr::alloc(i, Expr::Int32));
// If not in bindings then this can't be a violation?
Assignment::bindings_ty::iterator it2 = assignment.bindings.find(array);
if (it2 != assignment.bindings.end()) {
ref<Expr> isSeed = EqExpr::create(read,
ConstantExpr::alloc(it2->second[i],
Expr::Int8));
bool res;
bool success = solver->mustBeFalse(tmp, isSeed, res);
assert(success && "FIXME: Unhandled solver failure");
(void) success;
if (res) {
ref<ConstantExpr> value;
bool success = solver->getValue(tmp, read, value);
assert(success && "FIXME: Unhandled solver failure");
(void) success;
it2->second[i] = value->getZExtValue(8);
tmp.addConstraint(EqExpr::create(read,
ConstantExpr::alloc(it2->second[i],
Expr::Int8)));
} else {
tmp.addConstraint(isSeed);
}
}
}
bool res;
bool success = solver->mayBeTrue(state, assignment.evaluate(condition), res);
assert(success && "FIXME: Unhandled solver failure");
(void) success;
if (res)
return;
// We could still do a lot better than this, for example by looking at
// independence. But really, this shouldn't be happening often.
for (Assignment::bindings_ty::iterator it = assignment.bindings.begin(),
ie = assignment.bindings.end(); it != ie; ++it) {
const Array *array = it->first;
for (unsigned i=0; i<array->size; ++i) {
ref<Expr> read = ReadExpr::create(UpdateList(array, 0),
ConstantExpr::alloc(i, Expr::Int32));
ref<Expr> isSeed = EqExpr::create(read,
ConstantExpr::alloc(it->second[i],
Expr::Int8));
bool res;
bool success = solver->mustBeFalse(tmp, isSeed, res);
assert(success && "FIXME: Unhandled solver failure");
(void) success;
if (res) {
ref<ConstantExpr> value;
bool success = solver->getValue(tmp, read, value);
assert(success && "FIXME: Unhandled solver failure");
(void) success;
it->second[i] = value->getZExtValue(8);
tmp.addConstraint(EqExpr::create(read,
ConstantExpr::alloc(it->second[i],
Expr::Int8)));
} else {
tmp.addConstraint(isSeed);
}
}
}
#ifndef NDEBUG
{
bool res;
bool success =
solver->mayBeTrue(state, assignment.evaluate(condition), res);
assert(success && "FIXME: Unhandled solver failure");
(void) success;
assert(res && "seed patching failed");
}
#endif
}
|
