//
// Filename: divider.nac
// Purpose : N-address code (NAC) implementation for an iterative integer 
//           division algorithm based on the first algorithm in Niclaus Wirth's 
//           "A note on division".
// Author  : Nikolaos Kavvadias (C) 2011
// Date    : 09-Jun-2011
// Revision: 0.3.0 (09/06/11)
//           Initial version.

procedure divider (in u32 x, in u32 y, out u32 q, out u32 r)
{
  localvar u32 r0, q0, y0, y1;
  
S_1: 
  r0 <= mov x; 
  q0 <= ldc 0; 
  y0 <= mov y;
  y1 <= mov y;
  S_2 <= jmpun;
S_2:
  y1 <= shl y1, 1;
  S_2, S_3 <= jmple y1, x;
S_3:
  y1 <= shr y1, 1;
  q0 <= shl q0, 1;
  S_4, S_5 <= jmpge r0, y1;
S_4:
  r0 <= sub r0, y1;
  q0 <= add q0, 1;
  S_5 <= jmpun;
S_5:
  S_3, S_6 <= jmpne y1, y0;  
S_6:
  q <= mov q0;
  r <= mov r0;
}