[Bug rtl-optimization/126522] New: Wrong code with RTL ifcvt wrt alias sets

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126522

            Bug ID: 126522
           Summary: Wrong code with RTL ifcvt wrt alias sets
           Product: gcc
           Version: 17.0
            Status: UNCONFIRMED
          Keywords: wrong-code
          Severity: normal
          Priority: P3
         Component: rtl-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: ktkachov at gcc dot gnu.org
  Target Milestone: ---
            Target: aarch64

typedef int __attribute__((may_alias)) aint;

float gf;
int gi;

__attribute__((noipa)) int
f (void *p, int c, float v)
{
  int x;
  gf = v;
  if (c)
    x = *(aint *) p;            /* c == 1: p == &gf, may_alias read of a float.
 */
  else
    x = *(int *) p;             /* c == 0: p == &gi, plain read of an int.  */
  return x;
}

int
main (void)
{
  /* Then arm.  f stores 1.0f into gf and must read those bits back.  */
  gf = 0.0f;
  int r1 = f (&gf, 1, 1.0f);
  int expect = *(aint *) &gf;   /* the bits of 1.0f */
  if (r1 != expect)
    __builtin_abort ();

  /* Else arm, so that both sides of the diamond really run.  */
  gf = 0.0f;
  gi = 77;
  if (f (&gi, 0, 2.0f) != 77)
    __builtin_abort ();

  return 0;
}

on aarch64 at -O2  -fno-code-hoisting -fno-ssa-phiopt aborts and passes at -O0