[Bug middle-end/122519] New: Extra cset with movcc expansion due to ccmp depending on ter

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122519

            Bug ID: 122519
           Summary: Extra cset with movcc expansion due to ccmp depending
                    on ter
           Product: gcc
           Version: 16.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: enhancement
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pinskia at gcc dot gnu.org
  Target Milestone: ---
            Target: aarch64

```
int __GIMPLE  extra_cset (int a, int b, int c, int d)
{
  int t;
  bool bb;
  bool bb1;
  bb = a == 3;
  bb1 = b == 100;
  bb = bb & bb1;
  t = bb ? c : d;
  return t;
}

int __GIMPLE  ccmpok (int a, int b, int c, int d)
{
  int t;
  bool bb;
  bool bb2;
  bool bb1;
  bb2 = a == 3;
  bb1 = b == 100;
  bb = bb2 & bb1;
  t = bb ? c : d;
  return t;
}
```

With `-O1 -fgimple`

These 2 functions should produce the same code but since ccmp depends on ter
and ter in the extra_cset decides not to combine in the bb assignment, we get
an extra cset.
To fix this, we need to recognize ccmp outside of expand and not depend on TER.