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/******************************************************************************
* Top contributors (to current version):
* Aina Niemetz, Liana Hadarean, Mathias Preiner
*
* This file is part of the cvc5 project.
*
* Copyright (c) 2009-2025 by the authors listed in the file AUTHORS
* in the top-level source directory and their institutional affiliations.
* All rights reserved. See the file COPYING in the top-level source
* directory for licensing information.
* ****************************************************************************
*
* A simple demonstration of the solving capabilities of the cvc5
* bit-vector and array solvers.
*
*/
#include <cvc5/cvc5.h>
#include <iostream>
using namespace std;
using namespace cvc5;
int main()
{
TermManager tm;
Solver slv(tm);
slv.setOption("produce-models", "true"); // Produce Models
slv.setLogic("QF_ABV"); // Set the logic
// Consider the following code (where size is some previously defined constant):
//
//
// Assert (current_array[0] > 0);
// for (unsigned i = 1; i < k; ++i) {
// current_array[i] = 2 * current_array[i - 1];
// Assert (current_array[i-1] < current_array[i]);
// }
//
// We want to check whether the assertion in the body of the for loop holds
// throughout the loop.
// Setting up the problem parameters
uint32_t k = 4; // number of unrollings (should be a power of 2)
uint32_t index_size = 2; // size of the index, must be log2(k)
// Sorts
Sort elementSort = tm.mkBitVectorSort(32);
Sort indexSort = tm.mkBitVectorSort(index_size);
Sort arraySort = tm.mkArraySort(indexSort, elementSort);
// Variables
Term current_array = tm.mkConst(arraySort, "current_array");
// Making a bit-vector constant
Term zero = tm.mkBitVector(index_size, 0u);
// Asserting that current_array[0] > 0
Term current_array0 = tm.mkTerm(Kind::SELECT, {current_array, zero});
Term current_array0_gt_0 = tm.mkTerm(
Kind::BITVECTOR_SGT, {current_array0, tm.mkBitVector(32, 0u)});
slv.assertFormula(current_array0_gt_0);
// Building the assertions in the loop unrolling
Term index = tm.mkBitVector(index_size, 0u);
Term old_current = tm.mkTerm(Kind::SELECT, {current_array, index});
Term two = tm.mkBitVector(32, 2u);
std::vector<Term> assertions;
for (uint32_t i = 1; i < k; ++i)
{
index = tm.mkBitVector(index_size, i);
Term new_current = tm.mkTerm(Kind::BITVECTOR_MULT, {two, old_current});
// current[i] = 2 * current[i-1]
current_array =
tm.mkTerm(Kind::STORE, {current_array, index, new_current});
// current[i-1] < current [i]
Term current_slt_new_current =
tm.mkTerm(Kind::BITVECTOR_SLT, {old_current, new_current});
assertions.push_back(current_slt_new_current);
old_current = tm.mkTerm(Kind::SELECT, {current_array, index});
}
Term query = tm.mkTerm(Kind::NOT, {tm.mkTerm(Kind::AND, assertions)});
cout << "Asserting " << query << " to cvc5" << endl;
slv.assertFormula(query);
cout << "Expect sat." << endl;
cout << "cvc5: " << slv.checkSat() << endl;
// Getting the model
cout << "The satisfying model is:" << endl;
cout << " current_array = " << slv.getValue(current_array) << endl;
cout << " current_array[0] = " << slv.getValue(current_array0) << endl;
return 0;
}
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