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[/] [openrisc/] [trunk/] [gnu-src/] [gcc-4.5.1/] [gcc/] [testsuite/] [gcc.c-torture/] [execute/] [20040703-1.c] - Blame information for rev 297

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Line No. Rev Author Line
1 297 jeremybenn
/* PR 16341 */
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#define PART_PRECISION (sizeof (cpp_num_part) * 8)
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typedef unsigned int cpp_num_part;
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typedef struct cpp_num cpp_num;
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struct cpp_num
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{
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   cpp_num_part high;
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   cpp_num_part low;
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   int unsignedp;  /* True if value should be treated as unsigned.  */
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   int overflow;   /* True if the most recent calculation overflowed.  */
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};
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static  int
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num_positive (cpp_num num, unsigned int precision)
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{
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   if (precision > PART_PRECISION)
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     {
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       precision -= PART_PRECISION;
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       return (num.high & (cpp_num_part) 1 << (precision - 1)) == 0;
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     }
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   return (num.low & (cpp_num_part) 1 << (precision - 1)) == 0;
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}
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static cpp_num
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num_trim (cpp_num num, unsigned int precision)
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{
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   if (precision > PART_PRECISION)
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     {
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       precision -= PART_PRECISION;
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       if (precision < PART_PRECISION)
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         num.high &= ((cpp_num_part) 1 << precision) - 1;
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     }
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   else
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     {
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       if (precision < PART_PRECISION)
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         num.low &= ((cpp_num_part) 1 << precision) - 1;
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       num.high = 0;
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     }
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   return num;
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}
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/* Shift NUM, of width PRECISION, right by N bits.  */
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static cpp_num
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num_rshift (cpp_num num, unsigned int precision, unsigned int n)
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{
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   cpp_num_part sign_mask;
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   int x = num_positive (num, precision);
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   if (num.unsignedp || x)
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     sign_mask = 0;
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   else
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     sign_mask = ~(cpp_num_part) 0;
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   if (n >= precision)
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     num.high = num.low = sign_mask;
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   else
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     {
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       /* Sign-extend.  */
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       if (precision < PART_PRECISION)
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         num.high = sign_mask, num.low |= sign_mask << precision;
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       else if (precision < 2 * PART_PRECISION)
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         num.high |= sign_mask << (precision - PART_PRECISION);
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       if (n >= PART_PRECISION)
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         {
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           n -= PART_PRECISION;
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           num.low = num.high;
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           num.high = sign_mask;
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         }
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       if (n)
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         {
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           num.low = (num.low >> n) | (num.high << (PART_PRECISION - n));
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           num.high = (num.high >> n) | (sign_mask << (PART_PRECISION - n));
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         }
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     }
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   num = num_trim (num, precision);
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   num.overflow = 0;
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   return num;
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}
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                              #define num_zerop(num) ((num.low | num.high) == 0)
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#define num_eq(num1, num2) (num1.low == num2.low && num1.high == num2.high)
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cpp_num
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num_lshift (cpp_num num, unsigned int precision, unsigned int n)
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{
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   if (n >= precision)
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     {
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       num.overflow = !num.unsignedp && !num_zerop (num);
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       num.high = num.low = 0;
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     }
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   else
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     {
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       cpp_num orig;
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       unsigned int m = n;
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       orig = num;
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       if (m >= PART_PRECISION)
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         {
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           m -= PART_PRECISION;
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           num.high = num.low;
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           num.low = 0;
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         }
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       if (m)
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         {
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           num.high = (num.high << m) | (num.low >> (PART_PRECISION - m));
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           num.low <<= m;
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         }
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       num = num_trim (num, precision);
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       if (num.unsignedp)
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         num.overflow = 0;
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       else
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         {
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           cpp_num maybe_orig = num_rshift (num, precision, n);
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           num.overflow = !num_eq (orig, maybe_orig);
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         }
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     }
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   return num;
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}
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unsigned int precision = 64;
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unsigned int n = 16;
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cpp_num num = { 0, 3, 0, 0 };
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int main()
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{
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   cpp_num res = num_lshift (num, 64, n);
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   if (res.low != 0x30000)
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     abort ();
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   if (res.high != 0)
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     abort ();
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   if (res.overflow != 0)
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     abort ();
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   exit (0);
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}

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