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
|
//===-- MergeHandler.cpp --------------------------------------------------===//
//
// The KLEE Symbolic Virtual Machine
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "klee/MergeHandler.h"
#include "CoreStats.h"
#include "Executor.h"
#include "klee/ExecutionState.h"
namespace klee {
llvm::cl::opt<bool>
UseMerge("use-merge",
llvm::cl::init(false),
llvm::cl::desc("Enable support for klee_open_merge() and klee_close_merge() (experimental)"));
llvm::cl::opt<bool>
DebugLogMerge("debug-log-merge",
llvm::cl::init(false),
llvm::cl::desc("Enhanced verbosity for region based merge operations"));
llvm::cl::opt<bool>
UseIncompleteMerge("use-incomplete-merge",
llvm::cl::init(false),
llvm::cl::desc("Heuristic based merging"));
llvm::cl::opt<bool>
DebugLogIncompleteMerge("debug-log-incomplete-merge",
llvm::cl::init(false),
llvm::cl::desc("Debug info about incomplete merging"));
double MergeHandler::getMean() {
if (closedStateCount == 0)
return 0;
return closeMean;
}
unsigned MergeHandler::getInstrDistance(ExecutionState *es){
return es->steppedInstructions - openInstruction;
}
ExecutionState *MergeHandler::getPrioritizeState(){
for (ExecutionState *cur_state : openStates) {
bool stateIsClosed = (executor->inCloseMerge.find(cur_state) !=
executor->inCloseMerge.end());
if (!stateIsClosed && (getInstrDistance(cur_state) < 2 * getMean())) {
return cur_state;
}
}
return 0;
}
void MergeHandler::addOpenState(ExecutionState *es){
openStates.push_back(es);
}
void MergeHandler::removeOpenState(ExecutionState *es){
auto it = std::find(openStates.begin(), openStates.end(), es);
assert(it != openStates.end());
std::swap(*it, openStates.back());
openStates.pop_back();
}
void MergeHandler::removeFromCloseMergeSet(ExecutionState *es){
executor->inCloseMerge.erase(es);
}
void MergeHandler::addClosedState(ExecutionState *es,
llvm::Instruction *mp) {
// Update stats
++closedStateCount;
closeMean += (static_cast<double>(getInstrDistance(es)) - closeMean) /
closedStateCount;
// Remove from openStates
removeOpenState(es);
auto closePoint = reachedMergeClose.find(mp);
// If no other state has yet encountered this klee_close_merge instruction,
// add a new element to the map
if (closePoint == reachedMergeClose.end()) {
reachedMergeClose[mp].push_back(es);
executor->pauseState(*es);
} else {
// Otherwise try to merge with any state in the map element for this
// instruction
auto &cpv = closePoint->second;
bool mergedSuccessful = false;
for (auto& mState: cpv) {
if (mState->merge(*es)) {
executor->terminateState(*es);
mergedSuccessful = true;
break;
}
}
if (!mergedSuccessful) {
cpv.push_back(es);
executor->pauseState(*es);
}
}
}
void MergeHandler::releaseStates() {
for (auto& curMergeGroup: reachedMergeClose) {
for (auto curState: curMergeGroup.second) {
executor->continueState(*curState);
}
}
reachedMergeClose.clear();
}
bool MergeHandler::hasMergedStates() {
return (!reachedMergeClose.empty());
}
MergeHandler::MergeHandler(Executor *_executor, ExecutionState *es)
: executor(_executor), openInstruction(es->steppedInstructions),
closedStateCount(0), refCount(0) {
executor->mergeGroups.push_back(this);
addOpenState(es);
}
MergeHandler::~MergeHandler() {
auto it = std::find(executor->mergeGroups.begin(),
executor->mergeGroups.end(), this);
std::swap(*it, executor->mergeGroups.back());
executor->mergeGroups.pop_back();
releaseStates();
}
}
|
