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ExprSimplifier.cpp
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#include "ExprSimplifier.h"
#include "UnconstrainedVariableSimplifier.h"
#include <string>
#include <sstream>
#include <vector>
#include <algorithm>
#include <chrono>
using namespace std::chrono;
using namespace z3;
#define DEBUG false
expr ExprSimplifier::Simplify(expr expression)
{
unsigned oldHash = 0;
//expression = expression.simplify();
//expression = ApplyConstantEqualities(expression);
//return expression.simplify();
if (DEBUG)
{
std::cout << std::endl << std::endl << "input:" << std::endl;
std::cout << expression << std::endl;
}
int i = 0;
if (propagateUnconstrained)
{
expression = CanonizeBoundVariables(expression);
}
while (oldHash != expression.hash())
{
if (expression.is_const())
{
return expression;
}
i++;
oldHash = expression.hash();
clearCaches();
//std::cout << "Quantifier irrelevant start" << std::endl;
expression = PushQuantifierIrrelevantSubformulas(expression);
//std::cout << "Apply constant start" << std::endl;
expression = ApplyConstantEqualities(expression);
//std::cout << "Negate start" << std::endl;
expression = negate(expression);
//std::cout << "Der start" << std::endl;
expression = applyDer(expression);
//std::cout << "Negate start" << std::endl;
expression = negate(expression);
//std::cout << "Der start" << std::endl;
expression = applyDer(expression);
//std::cout << "Negate start" << std::endl;
expression = negate(expression);
//std::cout << "Der start" << std::endl;
expression = applyDer(expression);
//std::cout << "Negate start" << std::endl;
expression = negate(expression);
//std::cout << "Der start" << std::endl;
expression = applyDer(expression);
clearCaches();
//std::cout << "Refined quantifiers start" << std::endl;
expression = RefinedPushQuantifierIrrelevantSubformulas(expression);
//std::cout << "Der start" << std::endl;
expression = applyDer(expression);
//std::cout << "Negate start" << std::endl;
expression = negate(expression);
//std::cout << "Der start" << std::endl;
expression = applyDer(expression);
//std::cout << "Negate start" << std::endl;
expression = negate(expression);
//std::cout << "Der start" << std::endl;
expression = applyDer(expression);
if (propagateUnconstrained)
{
pushNegationsCache.clear();
expression = expression.simplify();
expression = PushNegations(expression);
UnconstrainedVariableSimplifier unconstrainedSimplifier(*context, expression);
unconstrainedSimplifier.SimplifyIte();
expression = unconstrainedSimplifier.GetExpr();
}
}
if (DEBUG)
{
UnconstrainedVariableSimplifier unconstrainedSimplifier(*context, expression);
unconstrainedSimplifier.PrintUnconstrained();
}
pushNegationsCache.clear();
expression = expression.simplify();
expression = PushNegations(expression);
//expression = UnflattenAddition(expression);
if (DEBUG)
{
std::cout << std::endl << std::endl << "nnf:" << std::endl;
std::cout << expression << std::endl;
}
context->check_error();
clearCaches();
return expression;
}
expr ExprSimplifier::ApplyConstantEqualities(const expr &e)
{
if (e.is_app())
{
func_decl dec = e.decl();
if (dec.name().str() == "and")
{
int argsCount = e.num_args();
for (int i=0; i < argsCount; i++)
{
expr variable(*context);
expr replacement(*context);
if (getSubstitutableEquality(e.arg(i), &variable, &replacement))
{
Z3_ast args [argsCount-1];
for (int j=0; j < argsCount-1; j++)
{
if (j < i)
{
args[j] = (Z3_ast)e.arg(j);
}
else
{
args[j] = (Z3_ast)e.arg(j+1);
}
}
expr withoutSubstitutedEquality = to_expr(*context, Z3_mk_and(*context, argsCount - 1, args));
expr_vector src(*context);
expr_vector dst(*context);
src.push_back(variable);
dst.push_back(replacement);
expr substituted = withoutSubstitutedEquality.substitute(src, dst);
return ApplyConstantEqualities(substituted);
}
}
return e;
}
}
return e;
}
expr ExprSimplifier::PushQuantifierIrrelevantSubformulas(const expr &e)
{
auto item = pushIrrelevantCache.find((Z3_ast)e);
if (item != pushIrrelevantCache.end())
{
return item->second;
}
if (!e.get_sort().is_bool())
{
return e;
}
if (e.is_app())
{
func_decl dec = e.decl();
int numArgs = e.num_args();
expr_vector arguments(*context);
for (int i = 0; i < numArgs; i++)
{
arguments.push_back(PushQuantifierIrrelevantSubformulas(e.arg(i)));
}
expr result = dec(arguments);
pushIrrelevantCache.insert({(Z3_ast)e, result});
return result;
}
else if (e.is_quantifier())
{
Z3_ast ast = (Z3_ast)e;
int numBound = Z3_get_quantifier_num_bound(*context, ast);
//expr_vector bound(*context);
Z3_sort sorts [numBound];
Z3_symbol decl_names [numBound];
for (int i = 0; i < numBound; i++)
{
sorts[i] = Z3_get_quantifier_bound_sort(*context, ast, i);
decl_names[i] = Z3_get_quantifier_bound_name(*context, ast, i);
//Z3_get_quantifier_bound_name()
//bound.push_back(e.arg(i));
}
if (e.body().is_app())
{
func_decl innerDecl = e.body().decl();
expr_vector bodyVector(*context);
expr_vector replacementVector(*context);
if (innerDecl.decl_kind() == Z3_OP_AND || innerDecl.decl_kind() == Z3_OP_OR)
{
int numInnerArgs = e.body().num_args();
for (int i = 0; i < numInnerArgs; i++)
{
expr arg = e.body().arg(i);
bool relevant = isRelevant(arg, numBound, 0);
if (!relevant)
{
replacementVector.push_back(decreaseDeBruijnIndices(arg, numBound, -1));
}
else
{
bodyVector.push_back(arg);
}
}
expr bodyExpr = innerDecl(bodyVector);
Z3_ast quantAst = Z3_mk_quantifier(
*context,
Z3_is_quantifier_forall(*context, ast),
Z3_get_quantifier_weight(*context, ast),
0,
{},
numBound,
sorts,
decl_names,
(Z3_ast)PushQuantifierIrrelevantSubformulas(bodyExpr));
replacementVector.push_back(to_expr(*context, quantAst));
expr result = innerDecl(replacementVector);
pushIrrelevantCache.insert({(Z3_ast)e, result});
return result;
}
}
Z3_ast quantAst = Z3_mk_quantifier(
*context,
Z3_is_quantifier_forall(*context, ast),
Z3_get_quantifier_weight(*context, ast),
0,
{},
numBound,
sorts,
decl_names,
(Z3_ast)PushQuantifierIrrelevantSubformulas(e.body()));
expr result = to_expr(*context, quantAst);
pushIrrelevantCache.insert({(Z3_ast)e, result});
return result;
}
else
{
return e;
}
}
expr ExprSimplifier::RefinedPushQuantifierIrrelevantSubformulas(const expr &e)
{
auto item = refinedPushIrrelevantCache.find((Z3_ast)e);
if (item != refinedPushIrrelevantCache.end())
{
return item->second;
}
if (!e.get_sort().is_bool())
{
return e;
}
if (e.is_app())
{
func_decl dec = e.decl();
int numArgs = e.num_args();
expr_vector arguments(*context);
for (int i = 0; i < numArgs; i++)
{
arguments.push_back(RefinedPushQuantifierIrrelevantSubformulas(e.arg(i)));
}
expr result = dec(arguments);
refinedPushIrrelevantCache.insert({e, result});
return result;
}
else if (e.is_quantifier())
{
Z3_ast ast = (Z3_ast)e;
int numBound = Z3_get_quantifier_num_bound(*context, ast);
//expr_vector bound(*context);
Z3_sort sorts [numBound];
Z3_symbol decl_names [numBound];
for (int i = 0; i < numBound; i++)
{
sorts[i] = Z3_get_quantifier_bound_sort(*context, ast, i);
decl_names[i] = Z3_get_quantifier_bound_name(*context, ast, i);
//Z3_get_quantifier_bound_name()
//bound.push_back(e.arg(i));
}
if (e.body().is_app())
{
func_decl innerDecl = e.body().decl();
expr_vector bodyVector(*context);
expr_vector replacementVector(*context);
if (innerDecl.decl_kind() == Z3_OP_AND || innerDecl.decl_kind() == Z3_OP_OR)
{
int numInnerArgs = e.body().num_args();
for (int i = 0; i < numInnerArgs; i++)
{
expr arg = e.body().arg(i);
bool relevant = isRelevant(arg, 1, 0);
if (!relevant)
{
replacementVector.push_back(decreaseDeBruijnIndices(arg, 1, -1));
}
else
{
bodyVector.push_back(arg);
}
}
Z3_sort outerSorts [numBound-1];
Z3_symbol outerDecl_names [numBound-1];
for (int i = 0; i < numBound-1; i++)
{
outerSorts[i] = sorts[i];
outerDecl_names[i] = decl_names[i];
}
Z3_sort innerSorts [1];
Z3_symbol innerDecl_names [1];
innerSorts[0] = sorts[numBound-1];
innerDecl_names[0] = decl_names[numBound-1];
expr bodyExpr = innerDecl(bodyVector);
Z3_ast innerQuantAst = Z3_mk_quantifier(
*context,
Z3_is_quantifier_forall(*context, ast),
Z3_get_quantifier_weight(*context, ast),
0,
{},
1,
innerSorts,
innerDecl_names,
(Z3_ast)RefinedPushQuantifierIrrelevantSubformulas(bodyExpr));
replacementVector.push_back(to_expr(*context, innerQuantAst));
expr outerBody = innerDecl(replacementVector);
//std::cout << outerBody << std::endl;
if (numBound == 1)
{
expr result = outerBody;
refinedPushIrrelevantCache.insert({(Z3_ast)e, result});
return result;
}
else
{
Z3_ast outerQuantAst = Z3_mk_quantifier(
*context,
Z3_is_quantifier_forall(*context, ast),
Z3_get_quantifier_weight(*context, ast),
0,
{},
numBound-1,
outerSorts,
outerDecl_names,
(Z3_ast)outerBody);
expr result = to_expr(*context, outerQuantAst);
refinedPushIrrelevantCache.insert({(Z3_ast)e, result});
return result;
}
}
}
Z3_ast quantAst = Z3_mk_quantifier(
*context,
Z3_is_quantifier_forall(*context, ast),
Z3_get_quantifier_weight(*context, ast),
0,
{},
numBound,
sorts,
decl_names,
(Z3_ast)RefinedPushQuantifierIrrelevantSubformulas(e.body()));
expr result = to_expr(*context, quantAst);
refinedPushIrrelevantCache.insert({(Z3_ast)e, result});
return result;
}
else
{
return e;
}
}
bool ExprSimplifier::getSubstitutableEquality(const expr &e, expr *variable, expr *replacement)
{
if (e.is_app())
{
func_decl dec = e.decl();
if (dec.decl_kind() == Z3_OP_EQ)
{
expr firstArg = e.arg(0);
if (firstArg.is_app() && firstArg.num_args() == 0 && firstArg.decl().name() != NULL && firstArg.is_bv() && !firstArg.is_numeral())
{
std::stringstream variableString;
variableString << firstArg;
std::stringstream replacementString;
replacementString << e.arg(1);
if (replacementString.str().find(variableString.str()) == std::string::npos)
{
*variable = firstArg;
*replacement = e.arg(1);
return true;
}
}
expr secondArg = e.arg(1);
if (secondArg.is_app() && secondArg.num_args() == 0 && secondArg.decl().name() != NULL && secondArg.is_bv() && !secondArg.is_numeral())
{
std::stringstream variableString;
variableString << secondArg;
std::stringstream replacementString;
replacementString << e.arg(0);
if (replacementString.str().find(variableString.str()) == std::string::npos)
{
*variable = secondArg;
*replacement = e.arg(0);
return true;
}
}
}
}
return false;
}
expr ExprSimplifier::decreaseDeBruijnIndices(const expr &e, int decreaseBy, int leastIndexToDecrease)
{
auto item = decreaseDeBruijnCache.find(std::make_tuple((Z3_ast)e, decreaseBy, leastIndexToDecrease));
if (item != decreaseDeBruijnCache.end())
{
return item->second;
}
if (e.is_var())
{
Z3_ast ast = (Z3_ast)e;
int deBruijnIndex = Z3_get_index_value(*context, ast);
if (deBruijnIndex > leastIndexToDecrease)
{
return to_expr(*context, Z3_mk_bound(*context, deBruijnIndex - decreaseBy, (Z3_sort)e.get_sort()));
}
else
{
return e;
}
}
else if (e.is_app())
{
func_decl dec = e.decl();
int numArgs = e.num_args();
expr_vector arguments(*context);
for (int i = 0; i < numArgs; i++)
{
arguments.push_back(decreaseDeBruijnIndices(e.arg(i), decreaseBy, leastIndexToDecrease));
}
expr result = dec(arguments);
decreaseDeBruijnCache.insert({std::make_tuple((Z3_ast)e, decreaseBy, leastIndexToDecrease), result});
return result;
}
else if (e.is_quantifier())
{
Z3_ast ast = (Z3_ast)e;
int numBound = Z3_get_quantifier_num_bound(*context, ast);
Z3_sort sorts [numBound];
Z3_symbol decl_names [numBound];
for (int i = 0; i < numBound; i++)
{
sorts[i] = Z3_get_quantifier_bound_sort(*context, ast, i);
decl_names[i] = Z3_get_quantifier_bound_name(*context, ast, i);
}
Z3_ast quantAst = Z3_mk_quantifier(
*context,
Z3_is_quantifier_forall(*context, ast),
Z3_get_quantifier_weight(*context, ast),
0,
{},
numBound,
sorts,
decl_names,
(Z3_ast)decreaseDeBruijnIndices(e.body(), decreaseBy, leastIndexToDecrease + numBound));
expr result = to_expr(*context, quantAst);
decreaseDeBruijnCache.insert({std::make_tuple((Z3_ast)e, decreaseBy, leastIndexToDecrease), result});
return result;
}
else
{
return e;
}
}
expr ExprSimplifier::negate(const expr &e)
{
assert(e.get_sort().is_bool());
if (e.is_quantifier())
{
Z3_ast ast = (Z3_ast)e;
int numBound = Z3_get_quantifier_num_bound(*context, ast);
Z3_sort sorts [numBound];
Z3_symbol decl_names [numBound];
for (int i = 0; i < numBound; i++)
{
sorts[i] = Z3_get_quantifier_bound_sort(*context, ast, i);
decl_names[i] = Z3_get_quantifier_bound_name(*context, ast, i);
}
Z3_ast quantAst = Z3_mk_quantifier(
*context,
!Z3_is_quantifier_forall(*context, ast),
Z3_get_quantifier_weight(*context, ast),
0,
{},
numBound,
sorts,
decl_names,
(Z3_ast)negate(e.body()));
return to_expr(*context, quantAst);
}
return !e;
}
expr ExprSimplifier::PushNegations(const expr &e)
{
auto item = pushNegationsCache.find((Z3_ast)e);
if (false && item != pushNegationsCache.end())
{
return item->second;
}
if (!e.get_sort().is_bool())
{
std::cout << e << std::endl;
}
//assert(e.get_sort().is_bool());
if (e.is_app())
{
if (e.decl().decl_kind() != Z3_OP_NOT)
{
func_decl dec = e.decl();
int numArgs = e.num_args();
expr_vector arguments(*context);
for (int i = 0; i < numArgs; i++)
{
if (e.arg(i).is_bool())
{
arguments.push_back(PushNegations(e.arg(i)));
}
else
{
arguments.push_back(e.arg(i));
}
}
auto result = dec(arguments);
pushNegationsCache.insert({(Z3_ast)e, result});
return result;
}
else
{
expr notBody = e.arg(0);
if (notBody.is_app())
{
func_decl innerDecl = notBody.decl();
int numArgs = notBody.num_args();
if (innerDecl.decl_kind() == Z3_OP_NOT)
{
auto result = PushNegations(notBody.arg(0));
//pushNegationsCache.insert({(Z3_ast)e, result});
return result;
}
else if (innerDecl.decl_kind() == Z3_OP_AND)
{
expr_vector arguments(*context);
for (int i = 0; i < numArgs; i++)
{
arguments.push_back(PushNegations(!notBody.arg(i)));
}
auto result = mk_or(arguments);
//pushNegationsCache.insert({(Z3_ast)e, result});
return result;
}
else if (innerDecl.decl_kind() == Z3_OP_OR)
{
expr_vector arguments(*context);
for (int i = 0; i < numArgs; i++)
{
arguments.push_back(PushNegations(!notBody.arg(i)));
}
auto result = mk_and(arguments);
//pushNegationsCache.insert({(Z3_ast)e, result});
return result;
}
else if (innerDecl.decl_kind() == Z3_OP_ITE)
{
auto result = (PushNegations(notBody.arg(0)) && PushNegations(!notBody.arg(1))) || (PushNegations(!notBody.arg(0)) && PushNegations(!notBody.arg(2)));
//pushNegationsCache.insert({(Z3_ast)e, result});
return result;
}
else if (innerDecl.decl_kind() == Z3_OP_IFF)
{
auto result = (PushNegations(notBody.arg(0)) && PushNegations(!notBody.arg(1))) || (PushNegations(!notBody.arg(0)) && PushNegations(notBody.arg(1)));
//pushNegationsCache.insert({(Z3_ast)e, result});
return result;
}
else if (innerDecl.decl_kind() == Z3_OP_SLEQ)
{
return notBody.arg(1) < notBody.arg(0);
}
else if (innerDecl.decl_kind() == Z3_OP_SLT)
{
return notBody.arg(1) <= notBody.arg(0);
}
else if (innerDecl.decl_kind() == Z3_OP_ULEQ)
{
return to_expr(*context, Z3_mk_bvult(*context, (Z3_ast)notBody.arg(1), (Z3_ast)notBody.arg(0)));
}
else if (innerDecl.decl_kind() == Z3_OP_ULT)
{
return to_expr(*context, Z3_mk_bvule(*context, (Z3_ast)notBody.arg(1), (Z3_ast)notBody.arg(0)));
}
}
else if (notBody.is_quantifier())
{
Z3_ast ast = (Z3_ast)notBody;
int numBound = Z3_get_quantifier_num_bound(*context, ast);
Z3_sort sorts [numBound];
Z3_symbol decl_names [numBound];
for (int i = 0; i < numBound; i++)
{
sorts[i] = Z3_get_quantifier_bound_sort(*context, ast, i);
decl_names[i] = Z3_get_quantifier_bound_name(*context, ast, i);
}
Z3_ast quantAst = Z3_mk_quantifier(
*context,
!Z3_is_quantifier_forall(*context, ast),
Z3_get_quantifier_weight(*context, ast),
0,
{},
numBound,
sorts,
decl_names,
(Z3_ast)PushNegations(!notBody.body()));
auto result = to_expr(*context, quantAst);
//pushNegationsCache.insert({(Z3_ast)e, result});
return result;
}
auto result = e;
//pushNegationsCache.insert({(Z3_ast)e, result});
return result;
}
}
if (e.is_quantifier())
{
Z3_ast ast = (Z3_ast)e;
int numBound = Z3_get_quantifier_num_bound(*context, ast);
Z3_sort sorts [numBound];
Z3_symbol decl_names [numBound];
for (int i = 0; i < numBound; i++)
{
sorts[i] = Z3_get_quantifier_bound_sort(*context, ast, i);
decl_names[i] = Z3_get_quantifier_bound_name(*context, ast, i);
}
Z3_ast quantAst = Z3_mk_quantifier(
*context,
Z3_is_quantifier_forall(*context, ast),
Z3_get_quantifier_weight(*context, ast),
0,
{},
numBound,
sorts,
decl_names,
(Z3_ast)PushNegations(e.body()));
auto result = to_expr(*context, quantAst);
pushNegationsCache.insert({(Z3_ast)e, result});
return result;
}
auto result = e;
pushNegationsCache.insert({(Z3_ast)e, result});
return result;
}
expr ExprSimplifier::PropagateInequalities(expr e)
{
if (e.is_app())
{
func_decl f = e.decl();
unsigned num = e.num_args();
std::string name = f.name().str();
bool substitute = false;
expr substituteVar = e;
expr substituteResult = e;
expr substitutionReason = e;
if (name == "or")
{
for (unsigned int i = 0; i < num; i++)
{
if (e.arg(i).is_app() && e.arg(i).decl().name().str() == "not" && e.arg(i).arg(0).is_app() && e.arg(i).arg(0).decl().name().str() == "=")
{
auto eqExpr = e.arg(i).arg(0);
if (isVar(eqExpr.arg(0)))
{
substitute = true;
substituteVar = eqExpr.arg(0);
substituteResult = eqExpr.arg(1);
substitutionReason = eqExpr;
}
else if (isVar(eqExpr.arg(1)))
{
substitute = true;
substituteVar = eqExpr.arg(1);
substituteResult = eqExpr.arg(0);
substitutionReason = eqExpr;
}
}
}
}
if (substitute)
{
expr_vector arguments(*context);
for (unsigned int i = 0; i < num; i++)
{
if (e.arg(i) != substitutionReason)
{
arguments.push_back(e.arg(i));
}
}
e = substitutionReason || PropagateInequalities(f(arguments));
}
expr_vector arguments(*context);
for (unsigned int i = 0; i < num; i++)
{
arguments.push_back(PropagateInequalities(e.arg(i)));
}
auto result = f(arguments);
return result;
}
else if (e.is_quantifier())
{
Z3_ast ast = (Z3_ast)e;
int numBound = Z3_get_quantifier_num_bound(*context, ast);
Z3_sort sorts [numBound];
Z3_symbol decl_names [numBound];
for (int i = 0; i < numBound; i++)
{
sorts[i] = Z3_get_quantifier_bound_sort(*context, ast, i);
decl_names[i] = Z3_get_quantifier_bound_name(*context, ast, i);
}
Z3_ast quantAst = Z3_mk_quantifier(
*context,
Z3_is_quantifier_forall(*context, ast),
Z3_get_quantifier_weight(*context, ast),
0,
{},
numBound,
sorts,
decl_names,
(Z3_ast)PropagateInequalities(e.body()));
auto result = to_expr(*context, quantAst);
return result;
}
return e;
}
expr ExprSimplifier::UnflattenAddition(const expr &e)
{
auto item = unflattenAdditionCache.find((Z3_ast)e);
if (item != unflattenAdditionCache.end())
{
return item->second;
}
if (e.is_app())
{
func_decl dec = e.decl();
int numArgs = e.num_args();
if (dec.name().str() == "bvadd")
{
if (numArgs == 1)
{
return e.arg(0);
}
else if (numArgs > 2)
{
std::vector<expr> arguments;
for (int i = 0; i < numArgs; i++)
{
arguments.push_back(e.arg(i));
}
std::cout << "in: " << e << std::endl;
std::sort(arguments.begin(), arguments.end(), [this](const expr& a, const expr& b) -> bool
{
bool seenA = seenAddends.find(a) != seenAddends.end();
bool seenB = seenAddends.find(b) != seenAddends.end();
if (seenA == seenB)
{
return (Z3_ast)a > (Z3_ast)b;
}
else
{
return seenA < seenB;
}
});
expr result = arguments.back();
arguments.pop_back();
while(arguments.size() != 0)
{
result = dec(arguments.back(), result);
seenAddends.insert(arguments.back());
arguments.pop_back();
}
std::cout << "out: " << result << std::endl;
return result;
}
else
{
return e;
}
}
else
{
expr_vector arguments(*context);
for (int i = 0; i < numArgs; i++)
{
arguments.push_back(UnflattenAddition(e.arg(i)));
}
expr result = dec(arguments);
unflattenAdditionCache.insert({(Z3_ast)e, result});
return result;
}
}
else if (e.is_quantifier())
{
seenAddends.clear();
Z3_ast ast = (Z3_ast)e;
int numBound = Z3_get_quantifier_num_bound(*context, ast);
Z3_sort sorts [numBound];
Z3_symbol decl_names [numBound];
for (int i = 0; i < numBound; i++)
{
sorts[i] = Z3_get_quantifier_bound_sort(*context, ast, i);
decl_names[i] = Z3_get_quantifier_bound_name(*context, ast, i);
}
Z3_ast quantAst = Z3_mk_quantifier(
*context,
Z3_is_quantifier_forall(*context, ast),
Z3_get_quantifier_weight(*context, ast),
0,
{},
numBound,
sorts,
decl_names,
(Z3_ast)UnflattenAddition(e.body()));
expr result = to_expr(*context, quantAst);
unflattenAdditionCache.insert({(Z3_ast)e, result});
return result;
}
else
{
unflattenAdditionCache.insert({(Z3_ast)e, e});
return e;
}
}
expr ExprSimplifier::CanonizeBoundVariables(const expr &e)
{
if (e.is_app())
{
func_decl dec = e.decl();
int numArgs = e.num_args();
expr_vector arguments(*context);
for (int i = 0; i < numArgs; i++)
{
arguments.push_back(CanonizeBoundVariables(e.arg(i)));
}
expr result = dec(arguments);
return result;
}
else if (e.is_quantifier())
{
Z3_ast ast = (Z3_ast)e;
int numBound = Z3_get_quantifier_num_bound(*context, ast);
Z3_sort sorts [numBound];
Z3_symbol decl_names [numBound];
for (int i = 0; i < numBound; i++)
{
sorts[i] = Z3_get_quantifier_bound_sort(*context, ast, i);
decl_names[i] = Z3_mk_string_symbol(*context, std::to_string(lastBound).c_str());
lastBound++;
}
Z3_ast quantAst = Z3_mk_quantifier(
*context,
Z3_is_quantifier_forall(*context, ast),
Z3_get_quantifier_weight(*context, ast),
0,
{},