public InvariantStatus check_modified(long value, int count) { if (modulus == 1) { // We shouldn't ever get to this case; the invariant should have been // destroyed instead. throw new Error("Modulus = 1"); } else if (no_samples_seen) { return InvariantStatus.NO_CHANGE; } else if (value == value1) { // no new information, so nothing to do return InvariantStatus.NO_CHANGE; } else if (modulus == 0) { // only one value seen so far // REACHABLE? if (modulus == 1) { return InvariantStatus.FALSIFIED; } } else { long new_modulus_long = Math.abs(MathMDE.gcd(modulus, value1 - value)); int new_modulus; if (new_modulus_long > Integer.MAX_VALUE || (new_modulus_long < Integer.MIN_VALUE)) { new_modulus = 1; } else { new_modulus = (int) new_modulus_long; assert new_modulus > 0; } if (new_modulus != modulus) { if (new_modulus == 1) { return InvariantStatus.FALSIFIED; } } } assert modulus != 1; return InvariantStatus.NO_CHANGE; }
public InvariantStatus add_modified(long value, int count) { if (modulus == 1) { // We shouldn't ever get to this case; the invariant should have been // destroyed instead. throw new Error("Modulus = 1"); // assert falsified; // // We already know this confidence fails // return; } else if (no_samples_seen) { value1 = value; no_samples_seen = false; return InvariantStatus.NO_CHANGE; } else if (value == value1) { // no new information, so nothing to do return InvariantStatus.NO_CHANGE; } else if (modulus == 0) { // only one value seen so far long new_modulus = Math.abs(value1 - value); if (new_modulus == 1) { return InvariantStatus.FALSIFIED; } modulus = new_modulus; remainder = MathMDE.mod_positive(value, modulus); } else { long new_modulus_long = Math.abs(MathMDE.gcd(modulus, value1 - value)); int new_modulus; if (new_modulus_long > Integer.MAX_VALUE || (new_modulus_long < Integer.MIN_VALUE)) { new_modulus = 1; } else { new_modulus = (int) new_modulus_long; assert new_modulus > 0; } if (new_modulus != modulus) { if (new_modulus == 1) { return InvariantStatus.FALSIFIED; } else { remainder = remainder % new_modulus; modulus = new_modulus; } } } assert modulus != 1; return InvariantStatus.NO_CHANGE; }