[Bug target/59744] miscompilation of unsigned comparison on aarch64

[pinskia at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59744

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |wrong-code
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2014-01-10
     Ever confirmed|0                           |1

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(insn 14 13 15 2 (set (reg:CC_SWP 66 cc)
        (compare:CC_SWP (neg:DI (reg:DI 0 x0 [ offset ]))
            (reg:DI 1 x1 [orig:85 D.3895 ] [85]))) t7.c:11 114 {*compare_negdi}
     (expr_list:REG_DEAD (reg:DI 1 x1 [orig:85 D.3895 ] [85])
        (expr_list:REG_DEAD (reg:DI 0 x0 [ offset ])
            (nil))))

--- CUT ---
Here is a testcase that fails at -O1 and above without any arguments.

int a[2] = { 10, 20 };

int
is_bigger (long, int) __attribute__((noinline,noclone));

int
is_bigger (long offset, int index)
{
  unsigned long size = -offset;

  if (size > a[index])
   return 1;

  return 0;
}


int
main (int argc, char** argv)
{
  long v;
  if (is_bigger(0, 0))
    __builtin_abort ();
  if (!is_bigger(1, 0))
    __builtin_abort ();
  if (is_bigger(-10, 0))
    __builtin_abort ();
  if (!is_bigger(10, 0))
    __builtin_abort ();
  return 0;
}