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[Bug tree-optimization/80620] [7/8 Regression] gcc produces wrong code with -O3


https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80620

--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Simplified testcase (for -O3):
long long int a = -465274079317386463LL;
int b = 856872806;
int c = -1940894202;
int d = 1718449211;
int e = -392681565;
unsigned long long int f = 13521452247506316486ULL;
int g = -13194608;

__attribute__((noinline, noclone))
void foo ()
{
  if (!a - a)
    c = b = 0;
  else
    d = 3UL * a == 0;
  if (g / a)
    e = 0 < -a + 500849970701012771LL + (unsigned long) -a;
  else
    f = 4081116982543369LL & a;
}

int
main ()
{
  asm volatile ("" : : : "memory");
  foo ();
  if (f != 2818598057803777LL)
    __builtin_abort ();
  return 0;
}

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