Updated user-propagator example (#5879)

examples/userPropagator/common.h

@@ -0,0 +1,77 @@
+#pragma once
+
+#include <algorithm>
+#include <chrono>
+#include <iostream>
+#include <random>
+#include <stack>
+#include <unordered_map>
+#include <unordered_set>
+#include <vector>
+#include <cstring>
+#include <optional>
+#include "z3++.h"
+
+using std::to_string;
+
+#define SIZE(x) std::extent<decltype(x)>::value
+
+// #define VERBOSE // Log events
+#ifdef VERBOSE
+#define WriteEmptyLine std::cout << std::endl
+#define WriteLine(x) std::cout << (x) << std::endl
+#define Write(x) std::cout << x
+#else
+#define WriteEmptyLine
+#define WriteLine(x)
+#define Write(x)
+#endif
+
+int log2i(unsigned n) {
+    if (n <= 0) {
+        return 0;
+    }
+    if (n <= 2) {
+        return 1;
+    }
+    unsigned l = 1;
+    int i = 0;
+    while (l < n) {
+        l <<= 1;
+        i++;
+    }
+    return i;
+}
+
+typedef std::vector<unsigned> simple_model;
+
+// For putting z3 expressions in hash-tables
+namespace std {
+
+    template<>
+    struct hash<simple_model> {
+        std::size_t operator()(const simple_model &m) const {
+            size_t hash = 0;
+            for (unsigned i = 0; i < m.size(); i++) {
+                hash *= m.size();
+                hash += m[i];
+            }
+            return hash;
+        }
+    };
+
+    template<>
+    struct hash<z3::expr> {
+        std::size_t operator()(const z3::expr &k) const {
+            return k.hash();
+        }
+    };
+
+    // Do not use Z3's == operator in the hash table
+    template<>
+    struct equal_to<z3::expr> {
+        bool operator()(const z3::expr &lhs, const z3::expr &rhs) const {
+            return z3::eq(lhs, rhs);
+        }
+    };
+}