1  /* Contributed by Jack Lloyd  <lloyd@randombit.net> */
       2  
       3  /* { dg-options "-O2 -ftree-vectorize" } */
       4  /* { dg-options "-O2 -ftree-vectorize -march=nocona" { target { i?86-*-* x86_64-*-* } } } */
       5  
       6  typedef unsigned long long word;
       7  
       8  const unsigned int MP_WORD_BITS = 64;
       9  const word MP_WORD_MASK = ~((word)0);
      10  const word MP_WORD_TOP_BIT = (word)1 << (8*sizeof(word) - 1);
      11  
      12  extern void abort (void);
      13  
      14  word do_div(word n1, word n0, word d)
      15  {
      16    word high = n1 % d, quotient = 0;
      17    unsigned int j;
      18  
      19    for(j = 0; j != MP_WORD_BITS; ++j)
      20      {
      21        word high_top_bit = (high & MP_WORD_TOP_BIT);
      22  
      23        high <<= 1;
      24        high |= (n0 >> (MP_WORD_BITS-1-j)) & 1;
      25        quotient <<= 1;
      26  
      27        if(high_top_bit || high >= d)
      28  	{
      29  	  high -= d;
      30  	  quotient |= 1;
      31  	}
      32      }
      33  
      34    return quotient;
      35  }
      36  
      37  int main()
      38  {
      39    word result;
      40  
      41    result = do_div(0x0000000000200000ll,
      42  		  0x0000000000000000ll,
      43  		  0x86E53497CE000000ll);
      44  
      45    
      46    if (result != 0x3CBA83)
      47      abort ();
      48  
      49    return 0;
      50  }