Skip to content

Commit

Permalink
[wip] Uninitialized Memory
Browse files Browse the repository at this point in the history
  • Loading branch information
ocelaiwo committed Oct 11, 2023
1 parent b9794c2 commit ab2cd9d
Show file tree
Hide file tree
Showing 40 changed files with 811 additions and 489 deletions.
8 changes: 7 additions & 1 deletion include/klee/ADT/Ref.h
Original file line number Diff line number Diff line change
Expand Up @@ -205,7 +205,13 @@ template <class T> class ref {

// assumes non-null arguments
bool equals(const ref &rhs) const {
assert(!isNull() && !rhs.isNull() && "Invalid call to compare()");
if (isNull() && rhs.isNull()) {
return true;
}
if (isNull() || rhs.isNull()) {
return false;
}
// assert(!isNull() && !rhs.isNull() && "Invalid call to compare()");
return get()->equals(*rhs.get());
}

Expand Down
71 changes: 51 additions & 20 deletions include/klee/ADT/SparseStorage.h
Original file line number Diff line number Diff line change
@@ -1,6 +1,8 @@
#ifndef KLEE_SPARSESTORAGE_H
#define KLEE_SPARSESTORAGE_H

#include "klee/ADT/Ref.h"
#include <algorithm>
#include <cassert>
#include <cstddef>
#include <iterator>
Expand All @@ -12,31 +14,47 @@ namespace llvm {
class raw_ostream;
};


namespace klee {

enum class Density {
Sparse,
Dense,
};

template <typename ValueType> class SparseStorage {
private:
std::unordered_map<size_t, ValueType> internalStorage;
ValueType defaultValue;
size_t rangeSize = 0;

bool contains(size_t key) const { return internalStorage.count(key) != 0; }

public:
SparseStorage(const ValueType &defaultValue = ValueType())
: defaultValue(defaultValue) {}

SparseStorage(const std::unordered_map<size_t, ValueType> &internalStorage,
const ValueType &defaultValue)
: defaultValue(defaultValue) {
for (auto &[index, value] : internalStorage) {
store(index, value);
}
}

SparseStorage(const std::vector<ValueType> &values,
const ValueType &defaultValue = ValueType())
: defaultValue(defaultValue) {
for (size_t idx = 0; idx < values.size(); ++idx) {
internalStorage[idx] = values[idx];
store(idx, values[idx]);
}
}

void store(size_t idx, const ValueType &value) {
if (value == defaultValue) {
internalStorage.erase(idx);
} else {
internalStorage[idx] = value;
rangeSize = std::max(rangeSize, idx + 1);
}
}

template <typename InputIterator>
Expand All @@ -52,12 +70,15 @@ template <typename ValueType> class SparseStorage {
}

size_t sizeOfSetRange() const {
return rangeSize;
size_t sizeOfRange = 0;
for (auto i : internalStorage) {
sizeOfRange = std::max(i.first, sizeOfRange);
}
return sizeOfRange;
}

bool operator==(const SparseStorage<ValueType> &another) const {
return defaultValue == another.defaultValue &&
compare(another) == 0;
return defaultValue == another.defaultValue && compare(another) == 0;
}

bool operator!=(const SparseStorage<ValueType> &another) const {
Expand All @@ -73,46 +94,56 @@ template <typename ValueType> class SparseStorage {
}

int compare(const SparseStorage<ValueType> &other) const {
std::map<size_t, ValueType> thisMap;
std::map<size_t, ValueType> otherMap;
for (auto i : internalStorage) {
thisMap.insert(i);
}
for (auto i : other.internalStorage) {
otherMap.insert(i);
}
if (thisMap == otherMap) {
auto ordered = calculateOrderedStorage();
auto otherOrdered = other.calculateOrderedStorage();

if (ordered == otherOrdered) {
return 0;
} else {
return thisMap < otherMap ? -1 : 1;
return ordered < otherOrdered ? -1 : 1;
}
}

std::map<size_t, ValueType> calculateOrderedStorage() const {
std::map<size_t, ValueType> ordered;
for (const auto &i : internalStorage) {
ordered.insert(i);
}
return ordered;
}

std::vector<ValueType> getFirstNIndexes(size_t n) const {
std::vector<ValueType> vectorized(n);
for (size_t i = 0; i < n; i++) {
vectorized[i] = load(i);
}
return vectorized;
}

const std::unordered_map<size_t, ValueType> &storage() const {
return internalStorage;
};

const ValueType &defaultV() const { return defaultValue; };

void reset() {
internalStorage.clear();
rangeSize = 0;
}

void reset(ValueType newDefault) {
defaultValue = newDefault;
internalStorage.clear();
rangeSize = 0;
}

// Specialized for unsigned char in .cpp
void print(llvm::raw_ostream &os) const;
void print(llvm::raw_ostream &os, Density) const;
};

template <typename U>
SparseStorage<unsigned char> sparseBytesFromValue(const U &value) {
const unsigned char *valueUnsignedCharIterator =
reinterpret_cast<const unsigned char *>(&value);
SparseStorage<unsigned char> result(sizeof(value));
SparseStorage<unsigned char> result;
result.store(0, valueUnsignedCharIterator,
valueUnsignedCharIterator + sizeof(value));
return result;
Expand Down
5 changes: 1 addition & 4 deletions include/klee/Expr/Expr.h
Original file line number Diff line number Diff line change
Expand Up @@ -629,10 +629,7 @@ class Array {

public:
bool isSymbolicArray() const { return !isConstantArray(); }
bool isConstantArray() const {
return isa<ConstantSource>(source) ||
isa<SymbolicSizeConstantSource>(source);
}
bool isConstantArray() const;

const std::string getName() const { return source->toString(); }
const std::string getIdentifier() const {
Expand Down
2 changes: 2 additions & 0 deletions include/klee/Expr/Parser/Lexer.h
Original file line number Diff line number Diff line change
Expand Up @@ -32,6 +32,8 @@ struct Token {
KWFalse, ///< 'false'
KWQuery, ///< 'query'
KWPath, ///< 'path'
KWDV, ///< 'DV'
KWNull, ///< 'null'
KWReserved, ///< fp[0-9]+([.].*)?, i[0-9]+
KWSymbolic, ///< 'symbolic'
KWTrue, ///< 'true'
Expand Down
14 changes: 10 additions & 4 deletions include/klee/Expr/SourceBuilder.h
Original file line number Diff line number Diff line change
Expand Up @@ -2,6 +2,7 @@
#define KLEE_SOURCEBUILDER_H

#include "klee/ADT/Ref.h"
#include "klee/ADT/SparseStorage.h"
#include "klee/Expr/SymbolicSource.h"
#include "klee/Module/KModule.h"

Expand All @@ -12,10 +13,14 @@ class SourceBuilder {
SourceBuilder() = delete;

static ref<SymbolicSource>
constant(const std::vector<ref<ConstantExpr>> &constantValues);
static ref<SymbolicSource> symbolicSizeConstant(unsigned defaultValue);
static ref<SymbolicSource> symbolicSizeConstantAddress(unsigned defaultValue,
unsigned version);
constant(SparseStorage<ref<ConstantExpr>> constantValues);

static ref<SymbolicSource> uninitialized(unsigned version,
const KInstruction *allocSite);
static ref<SymbolicSource>
symbolicSizeConstantAddress(unsigned version,
const KInstruction *allocSite,
ref<Expr> size);
static ref<SymbolicSource> makeSymbolic(const std::string &name,
unsigned version);
static ref<SymbolicSource> lazyInitializationAddress(ref<Expr> pointer);
Expand All @@ -27,6 +32,7 @@ class SourceBuilder {
int _index, KModule *km);
static ref<SymbolicSource> value(const llvm::Value &_allocSite, int _index,
KModule *km);
static ref<SymbolicSource> global(const llvm::GlobalVariable &name);
static ref<SymbolicSource> irreproducible(const std::string &name);
};

Expand Down
Loading

0 comments on commit ab2cd9d

Please sign in to comment.