/* Implementation of a 32-bit KISS generator which uses no multiply instructions */

// Initial seed
static unsigned long x = 123456789,
                     y = 234567891,
                     z = 345678912,
                     w = 456789123,
                     c = 0;

unsigned long JKISS32 ()
{
  long t;
  y ^= y << 5;
  y ^= y >> 7;
  y ^= y << 22;
  t = z + w + c;
  z = w;
  c = t < 0;
  w = t & 2147483647;
  x += 1411392427;
  return x + y + w;
}  // end of JKISS32

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  Serial.println("ESP32: mul.aa.ll test suite");

  int acclo, acchi;
  for (int i = 0; i < 1000; i++) {
    volatile int a = JKISS32();
    volatile int b = JKISS32();
    asm("mula.aa.ll  %0, %1": : "a"(a), "a"(b) : "memory");
    asm("rsr.ACCLO %0":"=r"(acclo));
    asm("rsr.ACCHI %0":"=r"(acchi));
    Serial.print(i);
    Serial.print(" ");
    Serial.print(acchi, HEX);
    Serial.print(" ");
    Serial.print(acclo, HEX);
    Serial.print(" (a=");
    Serial.print(a, HEX);
    Serial.print(", b=");
    Serial.print(b, HEX);
    Serial.println(")");
  }
}

void loop() {
  delay(10); // this speeds up the simulation
}