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ExprToBDDTransformer.cpp
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#include "ExprToBDDTransformer.h"
#include <cmath>
#include <iostream>
#include <sstream>
#include <list>
#include <climits>
#include <algorithm>
#include "HexHelper.h"
#define DEBUG false
bdd constIteBdd;
bdd constThenElse(const bdd &a, const bdd &b)
{
return bdd_ite(constIteBdd, a, b);
}
bddPair* pairToReplace;
bdd replacePair(const bdd &inputBdd)
{
return bdd_replace(inputBdd, pairToReplace);
}
bvec bvneg(bvec bv, int bitSize)
{
return bvec_add(bvec_map1(bv, bdd_not), bvec_con(bitSize, 1));
}
using namespace std;
using namespace z3;
ExprToBDDTransformer::ExprToBDDTransformer(z3::context &ctx, z3::expr e, InitialOrder initialOrder) : expression(e), initialOrder(initialOrder)
{
this->context = &ctx;
loadVars();
setApproximationType(SIGN_EXTEND);
}
void ExprToBDDTransformer::getVars(const z3::expr &e)
{
auto item = processedVarsCache.find((Z3_ast)e);
if (item != processedVarsCache.end())
{
return;
}
if (e.is_const() && !e.is_numeral())
{
if (e.get_sort().is_bool())
{
stringstream ss;
ss << e;
if (ss.str() == "true" || ss.str() == "false")
{
return;
}
var c = make_pair(ss.str(), 1);
constSet.insert(c);
}
else if (e.get_sort().is_bv())
{
stringstream ss;
ss << e;
if (ss.str() == "true" || ss.str() == "false")
{
return;
}
var c = make_pair(ss.str(), e.get_sort().bv_size());
constSet.insert(c);
}
}
else if (e.is_app())
{
func_decl f = e.decl();
unsigned num = e.num_args();
if (num == 0 && f.name() != NULL)
{
z3::sort s = f.range();
if (s.is_bv() && !e.is_numeral())
{
var c = make_pair(f.name().str(), s.bv_size());
constSet.insert(c);
}
else if (s.is_bool())
{
stringstream ss;
ss << e;
var c = make_pair(ss.str(), 1);
constSet.insert(c);
}
}
else
{
for (unsigned i = 0; i < num; i++)
{
getVars(e.arg(i));
}
}
}
else if(e.is_quantifier())
{
Z3_ast ast = (Z3_ast)e;
int boundVariables = Z3_get_quantifier_num_bound(*context, ast);
for (int i = 0; i < boundVariables; i++)
{
Z3_symbol z3_symbol = Z3_get_quantifier_bound_name(*context, ast, i);
Z3_sort z3_sort = Z3_get_quantifier_bound_sort(*context, ast, i);
symbol current_symbol(*context, z3_symbol);
z3::sort current_sort(*context, z3_sort);
if (current_sort.is_bool())
{
var c = make_pair(current_symbol.str(), 1);
boundVarSet.insert(c);
}
else if (current_sort.is_bv())
{
var c = make_pair(current_symbol.str(), current_sort.bv_size());
boundVarSet.insert(c);
}
}
getVars(e.body());
}
processedVarsCache.insert((Z3_ast)e);
}
void ExprToBDDTransformer::loadVars()
{
getVars(expression);
processedVarsCache.clear();
if (DEBUG)
{
std::cout << "Bound vars: " << boundVarSet.size() << std::endl;
}
set<var> allVars;
allVars.insert(constSet.begin(), constSet.end());
allVars.insert(boundVarSet.begin(), boundVarSet.end());
if (allVars.size() == 0)
{
bdd_extvarnum(1);
return;
}
VariableOrderer orderer(allVars, *context);
if (initialOrder == HEURISTIC)
{
orderer.OrderFor(expression);
}
else if (initialOrder == INTERLEAVE_ALL)
{
orderer.MergeAll();
}
list<list<var>> orderedGroups = orderer.GetOrdered();
int varCount = allVars.size();
int maxBitSize = 0;
for(auto const &v : allVars)
{
if (v.second > maxBitSize) maxBitSize = v.second;
}
bdd_extvarnum(varCount * maxBitSize);
if (DEBUG)
{
cout << "Groups: " << orderedGroups.size() << endl;
}
int offset = 0;
for(auto const &group : orderedGroups)
{
if (DEBUG)
{
cout << "Group size: " << group.size() << endl;
}
int i = 0;
for (auto const &v : group)
{
int bitnum = v.second;
bvec varBvec = bvec_var(bitnum, offset + i, group.size());
vars[v.first] = varBvec;
int indices[bitnum];
int currentVar = offset + i;
varIndices[v.first] = vector<int>();
for (int bit = 0; bit <= bitnum; bit++)
{
indices[bit] = currentVar;
varIndices[v.first].push_back(currentVar);
currentVar += group.size();
}
bdd varSet = bdd_makeset(indices, bitnum);
varSets[v.first] = varSet;
i++;
}
//bdd_intaddvarblock(offset, offset + maxBitSize * group.size() - 1, false);
offset += maxBitSize * group.size();
}
std::cout << "BDD variables: " << bdd_varnum() << std::endl;
}
void ExprToBDDTransformer::loadBDDsFromExpr(expr e)
{
bddExprCache.clear();
bvecExprCache.clear();
cacheHits = 0;
this->expression = e;
m_bdd = getBDDFromExpr(e, {}, true);
cout << "cache hits: " << cacheHits << std::endl;
//bdd_printorder();
}
bdd ExprToBDDTransformer::getConjunctionBdd(const vector<expr> &arguments, const vector<boundVar> &boundVars)
{
vector<bdd> results;
for (unsigned int i = 0; i < arguments.size(); i++)
{
bdd argBdd = getBDDFromExpr(arguments[i], boundVars);
if (argBdd.id() == 0)
{
return bdd_false();
}
else
{
results.push_back(argBdd);
}
}
if (results.size() == 0)
{
return bdd_true();
}
else
{
std::sort(results.begin(), results.end(),
[](const bdd& a, const bdd& b) -> bool
{
return bdd_nodecount(a) < bdd_nodecount(b);
});
bdd toReturn = results.at(0);
for (unsigned int i = 1; i < results.size(); i++)
{
toReturn = bdd_and(toReturn, results.at(i));
if (bdd_nodecount(toReturn) == 0)
{
if (toReturn.id() == 0)
{
return bdd_false();
}
}
}
return toReturn;
}
}
bdd ExprToBDDTransformer::getDisjunctionBdd(const vector<expr> &arguments, const vector<boundVar> &boundVars)
{
vector<bdd> results;
for (unsigned int i = 0; i < arguments.size(); i++)
{
bdd argBdd = getBDDFromExpr(arguments[i], boundVars);
if (argBdd.id() == 1)
{
return bdd_true();
}
else
{
results.push_back(argBdd);
}
}
if (results.size() == 0)
{
return bdd_false();
}
else
{
std::sort(results.begin(), results.end(),
[](const bdd& a, const bdd& b) -> bool
{
return bdd_nodecount(a) > bdd_nodecount(b);
});
bdd toReturn = results.at(0);
for (unsigned int i = 1; i < results.size(); i++)
{
toReturn = bdd_or(toReturn, results.at(i));
if (bdd_nodecount(toReturn) == 0)
{
if (toReturn.id() == 1)
{
return bdd_true();
}
}
}
return toReturn;
}
}
bdd ExprToBDDTransformer::getBDDFromExpr(const expr &e, vector<boundVar> boundVars, bool onlyExistentials)
{
assert(e.is_bool());
//cout << "BDD: " << e << endl;
auto item = bddExprCache.find((Z3_ast)e);
if (item != bddExprCache.end())
{
vector<boundVar> cachedBoundVars = (item->second).second;
bool correctBoundVars = true;
int pairsCount = min(boundVars.size(), cachedBoundVars.size());
for (int i = 0; i < pairsCount; i++)
{
string oldVarName = cachedBoundVars[cachedBoundVars.size() - i - 1].first;
string newVarName = boundVars[boundVars.size() - i - 1].first;
if (oldVarName != newVarName)
{
correctBoundVars = false;
}
}
if (correctBoundVars)
{
return (item->second).first;
}
}
if (e.is_var())
{
Z3_ast ast = (Z3_ast)e;
int deBruijnIndex = Z3_get_index_value(*context, ast);
boundVar bVar = boundVars[boundVars.size() - deBruijnIndex - 1];
return bvec_equ(vars[bVar.first], bvec_true(1));
}
else if (e.is_const())
{
//cout << "CONST: " << e << endl;
stringstream ss;
ss << e;
if (ss.str() == "true")
{
return bdd_true();
}
else if (ss.str() == "false")
{
return bdd_false();
}
bdd toReturn = bvec_equ(vars[ss.str()], bvec_true(1));
return toReturn;
}
else if (e.is_app())
{
//cout << "APP: " << e << endl;
func_decl f = e.decl();
unsigned num = e.num_args();
string functionName = f.name().str();
if (functionName == "=")
{
if (e.num_args() != 2)
{
std::cout << "= -- unsupported number of arguments" << std::endl;
std::cout << "unknown" << std::endl;
exit(1);
}
//std::cout << "eq: " << e << std::endl;
auto sort = e.arg(0).get_sort();
bdd result;
assert(sort.is_bv() || sort.is_bool());
if (sort.is_bv())
{
auto arg0 = getBvecFromExpr(e.arg(0), boundVars);
auto arg1 = getBvecFromExpr(e.arg(1), boundVars);
result = bvec_equ(arg0, arg1);
}
else if (sort.is_bool())
{
auto arg0 = getBDDFromExpr(e.arg(0), boundVars);
auto arg1 = getBDDFromExpr(e.arg(1), boundVars);
result = bdd_biimp(arg0, arg1);
}
return result;
}
else if (functionName == "not")
{
auto arg0 = getBDDFromExpr(e.arg(0), boundVars);
bdd result = bdd_not(arg0);
return result;
}
else if (functionName == "and")
{
vector<expr> arguments;
for (unsigned int i = 0; i < num; i++)
{
arguments.push_back(e.arg(i));
}
bdd result = getConjunctionBdd(arguments, boundVars);
bddExprCache.insert({(Z3_ast)e, {result, boundVars}});
return result;
}
else if (functionName == "or")
{
vector<expr> arguments;
for (unsigned int i = 0; i < num; i++)
{
arguments.push_back(e.arg(i));
}
bdd result = getDisjunctionBdd(arguments, boundVars);
bddExprCache.insert({(Z3_ast)e, {result, boundVars}});
return result;
}
else if (functionName == "=>")
{
if (e.num_args() != 2)
{
std::cout << "=> -- unsupported number of arguments" << std::endl;
std::cout << "unknown" << std::endl;
exit(1);
}
auto arg0 = getBDDFromExpr(e.arg(0), boundVars);
auto arg1 = getBDDFromExpr(e.arg(1), boundVars);
bdd result = bdd_imp(arg0, arg1);
bddExprCache.insert({(Z3_ast)e, {result, boundVars}});
return result;
}
else if (functionName == "bvule")
{
if (e.num_args() != 2)
{
std::cout << "bvule -- unsupported number of arguments" << std::endl;
std::cout << "unknown" << std::endl;
exit(1);
}
auto arg0 = getBvecFromExpr(e.arg(0), boundVars);
auto arg1 = getBvecFromExpr(e.arg(1), boundVars);
bdd result = bvec_lte(arg0, arg1);
bddExprCache.insert({(Z3_ast)e, {result, boundVars}});
return result;
}
else if (functionName == "bvult")
{
if (e.num_args() != 2)
{
std::cout << "bvult -- unsupported number of arguments" << std::endl;
std::cout << "unknown" << std::endl;
exit(1);
}
auto arg0 = getBvecFromExpr(e.arg(0), boundVars);
auto arg1 = getBvecFromExpr(e.arg(1), boundVars);
bdd result = bvec_lth(arg0, arg1);
bddExprCache.insert({(Z3_ast)e, {result, boundVars}});
return result;
}
else if (functionName == "bvugr")
{
if (e.num_args() != 2)
{
std::cout << "bvugr -- unsupported number of arguments" << std::endl;
std::cout << "unknown" << std::endl;
exit(1);
}
auto arg0 = getBvecFromExpr(e.arg(0), boundVars);
auto arg1 = getBvecFromExpr(e.arg(1), boundVars);
bdd result = bvec_gte(arg0, arg1);
bddExprCache.insert({(Z3_ast)e, {result, boundVars}});
return result;
}
else if (functionName == "bvugt")
{
if (e.num_args() != 2)
{
std::cout << "bvugt -- unsupported number of arguments" << std::endl;
std::cout << "unknown" << std::endl;
exit(1);
}
auto arg0 = getBvecFromExpr(e.arg(0), boundVars);
auto arg1 = getBvecFromExpr(e.arg(1), boundVars);
bdd result = bvec_gth(arg0, arg1);
bddExprCache.insert({(Z3_ast)e, {result, boundVars}});
return result;
}
else if (functionName == "bvsle")
{
if (e.num_args() != 2)
{
std::cout << "bvsle -- unsupported number of arguments" << std::endl;
std::cout << "unknown" << std::endl;
exit(1);
}
auto arg0 = getBvecFromExpr(e.arg(0), boundVars);
auto arg1 = getBvecFromExpr(e.arg(1), boundVars);
int size = e.arg(0).get_sort().bv_size();
bdd head0 = arg0[size-1];
bdd head1 = arg1[size-1];
bvec tail0 = bvec_coerce(size - 1, arg0);
bvec tail1 = bvec_coerce(size - 1, arg1);
bdd differentSigns = bdd_and(bdd_biimp(head0, bdd_true()), bdd_biimp(head1, bdd_false()));
bdd sameSigns = bdd_biimp(head0, head1);
bdd sameSignsLte = bdd_and(sameSigns, bvec_lte(tail0, tail1));
bdd result = bdd_or(differentSigns, sameSignsLte);
bddExprCache.insert({(Z3_ast)e, {result, boundVars}});
return result;
}
else if (functionName == "bvslt")
{
if (e.num_args() != 2)
{
std::cout << "bvslt -- unsupported number of arguments" << std::endl;
std::cout << "unknown" << std::endl;
exit(1);
}
auto arg0 = getBvecFromExpr(e.arg(0), boundVars);
auto arg1 = getBvecFromExpr(e.arg(1), boundVars);
int size = e.arg(0).get_sort().bv_size();
bdd head0 = arg0[size-1];
bdd head1 = arg1[size-1];
bvec tail0 = bvec_coerce(size - 1, arg0);
bvec tail1 = bvec_coerce(size - 1, arg1);
bdd differentSigns = bdd_and(bdd_biimp(head0, bdd_true()), bdd_biimp(head1, bdd_false()));
bdd sameSigns = bdd_biimp(head0, head1);
bdd sameSignsLth = bdd_and(sameSigns, bvec_lth(tail0, tail1));
bdd result = bdd_or(differentSigns, sameSignsLth);
bddExprCache.insert({(Z3_ast)e, {result, boundVars}});
return result;
}
else if (functionName == "iff")
{
if (e.num_args() != 2)
{
std::cout << "iff -- unsupported number of arguments" << std::endl;
std::cout << "unknown" << std::endl;
exit(1);
}
auto arg0 = getBDDFromExpr(e.arg(0), boundVars);
auto arg1 = getBDDFromExpr(e.arg(1), boundVars);
bdd result = bdd_biimp(arg0, arg1);
bddExprCache.insert({(Z3_ast)e, {result, boundVars}});
return result;
}
else if (functionName == "if")
{
if (e.num_args() != 3)
{
std::cout << "if -- unsupported number of arguments" << std::endl;
std::cout << "unknown" << std::endl;
exit(1);
}
auto arg0 = getBDDFromExpr(e.arg(0), boundVars);
auto arg1 = getBDDFromExpr(e.arg(1), boundVars);
auto arg2 = getBDDFromExpr(e.arg(2), boundVars);
bdd result = bdd_ite(arg0, arg1, arg2);
bddExprCache.insert({(Z3_ast)e, {result, boundVars}});
return result;
}
else
{
cout << "function " << f.name().str() << endl;
}
}
else if(e.is_quantifier())
{
Z3_ast ast = (Z3_ast)e;
int boundVariables = Z3_get_quantifier_num_bound(*context, ast);
for (int i = 0; i < boundVariables; i++)
{
Z3_symbol z3_symbol = Z3_get_quantifier_bound_name(*context, ast, i);
//Z3_sort z3_sort = Z3_get_quantifier_bound_sort(*context, ast, i);
symbol current_symbol(*context, z3_symbol);
string c = current_symbol.str();
if (Z3_is_quantifier_forall(*context, ast))
{
boundVars.push_back(std::pair<string, BoundType>(c, UNIVERSAL));
}
else
{
boundVars.push_back(std::pair<string, BoundType>(c, EXISTENTIAL));
}
}
bdd bodyBdd;
if (!onlyExistentials || Z3_is_quantifier_forall(*context, ast))
{
if (!e.body().is_app() || (e.body().decl().decl_kind() != Z3_OP_OR && e.body().decl().decl_kind() != Z3_OP_AND))
{
bodyBdd = getBDDFromExpr(e.body(), boundVars);
}
}
for (int i = boundVariables - 1; i >= 0; i--)
{
Z3_symbol z3_symbol = Z3_get_quantifier_bound_name(*context, ast, i);
symbol current_symbol(*context, z3_symbol);
if (Z3_is_quantifier_forall(*context, ast))
{
if (i == boundVariables - 1 && e.body().is_app() && (e.body().decl().decl_kind() == Z3_OP_OR || e.body().decl().decl_kind() == Z3_OP_AND))
{
int numArgs = e.body().num_args();
std::vector<expr> leftHalf;
std::vector<expr> rightHalf;
for (int j = 0; j < numArgs; j++)
{
if (j < numArgs / 2)
{
leftHalf.push_back(e.body().arg(j));
}
else
{
rightHalf.push_back(e.body().arg(j));
}
}
if (e.body().decl().decl_kind() == Z3_OP_OR)
{
bodyBdd = bdd_appall(getDisjunctionBdd(leftHalf, boundVars),
getDisjunctionBdd(rightHalf, boundVars),
bddop_or,
varSets[current_symbol.str()]);
}
else
{
bodyBdd = bdd_appall(getConjunctionBdd(leftHalf, boundVars),
getConjunctionBdd(rightHalf, boundVars),
bddop_and,
varSets[current_symbol.str()]);
}
}
else
{
bodyBdd = bdd_forall(bodyBdd, varSets[current_symbol.str()]);
}
}
else
{
if (onlyExistentials)
{
return getBDDFromExpr(e.body(), boundVars, true);
}
if (i == boundVariables - 1 && e.body().is_app() && (e.body().decl().decl_kind() == Z3_OP_OR || e.body().decl().decl_kind() == Z3_OP_AND))
{
int numArgs = e.body().num_args();
std::vector<expr> leftHalf;
std::vector<expr> rightHalf;
for (int j = 0; j < numArgs; j++)
{
if (j < numArgs / 2)
{
leftHalf.push_back(e.body().arg(j));
}
else
{
rightHalf.push_back(e.body().arg(j));
}
}
if (e.body().decl().decl_kind() == Z3_OP_OR)
{
bodyBdd = bdd_appex(getDisjunctionBdd(leftHalf, boundVars),
getDisjunctionBdd(rightHalf, boundVars),
bddop_or,
varSets[current_symbol.str()]);
}
else
{
bodyBdd = bdd_appex(getConjunctionBdd(leftHalf, boundVars),
getConjunctionBdd(rightHalf, boundVars),
bddop_and,
varSets[current_symbol.str()]);
}
}
else
{
bodyBdd = bdd_exist(bodyBdd, varSets[current_symbol.str()]);
}
}
}
bddExprCache.insert({(Z3_ast)e, {bodyBdd, boundVars}});
return bodyBdd;
}
cout << "bdd else: " << e << endl;
abort();
}
bvec ExprToBDDTransformer::getBvecFromExpr(const expr &e, vector<boundVar> boundVars)
{
assert(e.is_bv());
//cout << e << endl;
auto item = bvecExprCache.find((Z3_ast)e);
if (item != bvecExprCache.end())
{
vector<boundVar> cachedBoundVars = (item->second).second;
bool correctBoundVars = true;
int pairsCount = min(boundVars.size(), cachedBoundVars.size());
for (int i = 0; i < pairsCount; i++)
{
string oldVarName = cachedBoundVars[cachedBoundVars.size() - i - 1].first;
string newVarName = boundVars[boundVars.size() - i - 1].first;
if (oldVarName != newVarName)
{
correctBoundVars = false;
}
}
if (correctBoundVars)
{
cacheHits++;
//std::cout << "cache hit: " << e << std::endl;
return (item->second).first;
}
}
if (e.is_var())
{
Z3_ast ast = (Z3_ast)e;
int deBruijnIndex = Z3_get_index_value(*context, ast);
boundVar bVar = boundVars[boundVars.size() - deBruijnIndex - 1];
if (bVar.second == EXISTENTIAL && exisentialBitWidth != 0)
{
int bitSize = e.get_sort().bv_size();
if (exisentialBitWidth > 0)
{
int newWidth = min(exisentialBitWidth, bitSize);
bvec var = vars[bVar.first];
for (int i = newWidth; i < bitSize; i++)
{
if (approximationType == ZERO_EXTEND)
{
var.set(i, bdd_false());
}
else if (approximationType == SIGN_EXTEND)
{
var.set(i, var[i - 1]);
}
}
return var;
}
else
{
int newWidth = min(-exisentialBitWidth, bitSize);
bvec var = vars[bVar.first];
for (int i = bitSize - newWidth - 1; i >= 0; i--)
{
if (approximationType == ZERO_EXTEND)
{
var.set(i, bdd_false());
}
else if (approximationType == SIGN_EXTEND)
{
var.set(i, var[i + 1]);
}
}
return var;
}
}
if (bVar.second == UNIVERSAL && universalBitWidth != 0)
{
int bitSize = e.get_sort().bv_size();
if (universalBitWidth > 0)
{
int newWidth = min(universalBitWidth, bitSize);
bvec var = vars[bVar.first];
for (int i = newWidth; i < bitSize; i++)
{
if (approximationType == ZERO_EXTEND)
{
var.set(i, bdd_false());
}
else if (approximationType == SIGN_EXTEND)
{
var.set(i, var[i - 1]);
}
}
return var;
}
else
{
int newWidth = min(-universalBitWidth, bitSize);
bvec var = vars[bVar.first];
for (int i = bitSize - newWidth - 1; i >= 0; i--)
{
if (approximationType == ZERO_EXTEND)
{
var.set(i, bdd_false());
}
else if (approximationType == SIGN_EXTEND)
{
var.set(i, var[i + 1]);
}
}
return var;
}
}
else
{
return vars[bVar.first];
}
}
else if (e.is_numeral())
{
return getNumeralBvec(e);
}
else if (e.is_const())
{
stringstream ss;
ss << e;
if (exisentialBitWidth != 0)
{
int bitSize = e.get_sort().bv_size();
if (exisentialBitWidth > 0)
{
int newWidth = min(exisentialBitWidth, bitSize);
bvec var = vars[ss.str()];
for (int i = newWidth; i < bitSize; i++)
{
if (approximationType == ZERO_EXTEND)
{
var.set(i, bdd_false());
}
else if (approximationType == SIGN_EXTEND)
{
var.set(i, var[i - 1]);
}
}
return var;
}
else
{
int newWidth = min(-exisentialBitWidth, bitSize);
bvec var = vars[ss.str()];
for (int i = bitSize - newWidth - 1; i >= 0; i--)
{
if (approximationType == ZERO_EXTEND)
{
var.set(i, bdd_false());
}
else if (approximationType == SIGN_EXTEND)
{
var.set(i, var[i + 1]);
}
}
return var;
}
}
else
{
return vars[ss.str()];
}
}
else if (e.is_app())
{
func_decl f = e.decl();
unsigned num = e.num_args();
string functionName = f.name().str();
if (functionName == "bvadd")
{
bvec toReturn = getBvecFromExpr(e.arg(0), boundVars);
for (unsigned int i = 1; i < num; i++)
{
toReturn = bvec_add(toReturn, getBvecFromExpr(e.arg(i), boundVars));
}
bvecExprCache.insert({(Z3_ast)e, {toReturn, boundVars}});
return toReturn;
}
else if (functionName == "bvsub")
{
if (e.num_args() != 2)
{
std::cout << "bvsub -- unsupported number of arguments" << std::endl;
std::cout << "unknown" << std::endl;
exit(1);
}
auto arg0 = getBvecFromExpr(e.arg(0), boundVars);
auto arg1 = getBvecFromExpr(e.arg(1), boundVars);
bvec result = bvec_sub(arg0, arg1);
bvecExprCache.insert({(Z3_ast)e, {result, boundVars}});
return result;
}
else if (functionName == "bvshl")
{
if (e.arg(1).is_numeral())
{
auto arg0 = getBvecFromExpr(e.arg(0), boundVars);
bvec result = bvec_shlfixed(arg0, getNumeralValue(e.arg(1)), bdd_false());
bvecExprCache.insert({(Z3_ast)e, {result, boundVars}});
return result;
}
else
{
auto arg0 = getBvecFromExpr(e.arg(0), boundVars);