//
// integer
// 31-bit signed integer support
// F.J. Alberti
//


case kPushint:
  // Push integer literal
  m->top[--m->pp] = *(int32*)&fetch(pc)<<1;
  pc += ALIGNMENT(4);
  checkOverflow(m, 0)
  break;


case kPushint0:
  // Push integer literal 0
  m->top[--m->pp] = 0<<1;
  checkOverflow(m, 0)
  break;


case kPushint1:
  // Push integer literal 1
  m->top[--m->pp] = 1<<1;
  checkOverflow(m, 0)
  break;


case kPushint2:
  // Push integer literal 2
  m->top[--m->pp] = 2<<1;
  checkOverflow(m, 0)
  break;
  

case kPushbyte:
  // Push a byte (promoted to an 31-bit int)
  m->top[--m->pp] = (int)fetch(pc)<<1;
  pc += ALIGNMENT(1);
  checkOverflow(m, 0)
  break;


case kIntadd: {
  // Addition
#if defined(SCOL_DEBUG)
  checkUnderflow(m);
#endif
  int val1 = m->top[m->pp++];
  int val0 = m->top[m->pp];
  m->top[m->pp] = (val0 == NIL || val1 == NIL) ? NIL : val0+val1;
  break;
}


case kIntadd1: {
  // Increment
  int val = m->top[m->pp];
  m->top[m->pp] = (val == NIL) ? NIL : val+(1<<1);
  break;
}


case kIntsub: {
  // Substraction
#if defined(SCOL_DEBUG)
  checkUnderflow(m);
#endif
  int val1 = m->top[m->pp++];
  int val0 = m->top[m->pp];
  m->top[m->pp] = (val0 == NIL || val1 == NIL) ? NIL : val0-val1;
  break;
}


case kIntsub1: {
  // Decrement
  int val = m->top[m->pp];
  m->top[m->pp] = (val == NIL) ? NIL : val-(1<<1);
  break;
}


case kIntmul: {
  // Multiplication
#if defined(SCOL_DEBUG)
  checkUnderflow(m);
#endif
  int val1 = m->top[m->pp++];
  int val0 = m->top[m->pp];
  m->top[m->pp] = (val0 == NIL || val1 == NIL) ? NIL : val0*(val1>>1);
  break;
}


case kIntdiv: {
  // Division
#if defined(SCOL_DEBUG)
  checkUnderflow(m);
#endif
  int val1 = m->top[m->pp++];
  int val0 = m->top[m->pp];
  if (val0 == NIL || val1 == NIL) {
    m->top[m->pp] = NIL;
    break;
  }
  if (val1 == 0) // actually I should have done val1>>1
    throw Exception(MERRNUL);
  m->top[m->pp] = (val0/val1)<<1;
  break;
}


case kIntmod: {
  // Modulus
#if defined(SCOL_DEBUG)
  checkUnderflow(m);
#endif
  int val1 = m->top[m->pp++];
  int val0 = m->top[m->pp];
  if (val0 == NIL || val1 == NIL) {
    m->top[m->pp] = NIL;
    break;
  }
  if (val1 == 0) // actually I should have done val1>>1
    throw Exception(MERRNUL);
  m->top[m->pp] = ((val0>>1)%(val1>>1))<<1;
  break;
}


case kIntneg: {
  // Negation
  int val = m->top[m->pp];
  m->top[m->pp] = (val == NIL) ? NIL : -val;
  break;
}


case kIntand: {
  // Bitwise and
#if defined(SCOL_DEBUG)
  checkUnderflow(m);
#endif
  int val1 = m->top[m->pp++];
  int val0 = m->top[m->pp];
  m->top[m->pp] = (val0 == NIL || val1 == NIL) ? NIL : val0&val1;
  break;
}


case kIntor: {
  // Bitwise or
#if defined(SCOL_DEBUG)
  checkUnderflow(m);
#endif
  int val1 = m->top[m->pp++];
  int val0 = m->top[m->pp];
  m->top[m->pp] = (val0 == NIL || val1 == NIL) ? NIL : val0|val1;
  break;
}


case kIntxor: {
  // Bitwise xor
#if defined(SCOL_DEBUG)
  checkUnderflow(m);
#endif
  int val1 = m->top[m->pp++];
  int val0 = m->top[m->pp];
  m->top[m->pp] = (val0 == NIL || val1 == NIL) ? NIL : val0^val1;
  break;
}


case kIntnot: {
  // Bitwise not
  int val = m->top[m->pp];
  // Expression modified with respect to original code
  m->top[m->pp] = (val == NIL) ? NIL : (~val)&0xfffffffe;
  break;
}


case kIntshl: {
  // Shift left
#if defined(SCOL_DEBUG)
  checkUnderflow(m);
#endif
  int val1 = m->top[m->pp++];
  int val0 = m->top[m->pp];
  m->top[m->pp] = (val0 == NIL || val1 == NIL) ? NIL : val0<<(val1>>1);
  break;
}


case kIntshr: {
  // Shift right
#if defined(SCOL_DEBUG)
  checkUnderflow(m);
#endif
  int val1 = m->top[m->pp++];
  int val0 = m->top[m->pp];
  // Expression modified with respect to original code
  m->top[m->pp] = (val0 == NIL || val1 == NIL) ? NIL : (val0>>(val1>>1))&0xfffffffe; 
  break;
}


case kInteq: {
  // Equality relation
#if defined(SCOL_DEBUG)
  checkUnderflow(m);
#endif
  int val1 = m->top[m->pp++];
  int val0 = m->top[m->pp];
  m->top[m->pp] = (val0 == val1) ? 2 : 0;
  break;
}


case kIntne: {
  // Non-equality relation
#if defined(SCOL_DEBUG)
  checkUnderflow(m);
#endif
  int val1 = m->top[m->pp++];
  int val0 = m->top[m->pp];
  m->top[m->pp] = (val0 != val1) ? 2 : 0;
  break;
}


case kIntlt: {
  // Less-than relation
#if defined(SCOL_DEBUG)
  checkUnderflow(m);
#endif
  int val1 = m->top[m->pp++];
  int val0 = m->top[m->pp];
  m->top[m->pp] = (val0 == NIL || val1 == NIL) ? NIL : (val0 < val1) ? 2 : 0;
  break;
}


case kIntgt: {
  // Greater-than relation
#if defined(SCOL_DEBUG)
  checkUnderflow(m);
#endif
  int val1 = m->top[m->pp++];
  int val0 = m->top[m->pp];
  m->top[m->pp] = (val0 == NIL || val1 == NIL) ? NIL : (val0 > val1) ? 2 : 0;
  break;
}


case kIntle: {
  // Less-than-or-equal relation
#if defined(SCOL_DEBUG)
  checkUnderflow(m);
#endif
  int val1 = m->top[m->pp++];
  int val0 = m->top[m->pp];
  m->top[m->pp] = (val0 == NIL || val1 == NIL) ? NIL : (val0 <= val1) ? 2 : 0;
  break;
}


case kIntge: {
  // Greater-than-or-equal relation
#if defined(SCOL_DEBUG)
  checkUnderflow(m);
#endif
  int val1 = m->top[m->pp++];
  int val0 = m->top[m->pp];
  m->top[m->pp] = (val0 == NIL || val1 == NIL) ? NIL : (val0 >= val1) ? 2 : 0;
  break;
}


case kBooland: {
  // Boolean and
#if defined(SCOL_DEBUG)
  checkUnderflow(m);
#endif
  int val1 = m->top[m->pp++];
  int val0 = m->top[m->pp];
  m->top[m->pp] = (val0 == NIL || val1 == NIL) ? NIL : (val0 && val1) ? 2 : 0;
  break;
}


case kBoolor: {
  // Boolean or
#if defined(SCOL_DEBUG)
  checkUnderflow(m);
#endif
  int val1 = m->top[m->pp++];
  int val0 = m->top[m->pp];
  m->top[m->pp] = (val0 == NIL || val1 == NIL) ? NIL : (val0 || val1) ? 2 : 0;
  break;
}


case kBoolnot: {
  // Boolean not
#if defined(SCOL_DEBUG)
  checkUnderflow(m);
#endif
  int val = m->top[m->pp];
  m->top[m->pp] = (val == NIL) ? NIL : val ? 0 : 2;
  break;
}