[Bug tree-optimization/107053] New: ones bits is not tracked and popcount is not tracked

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107053

            Bug ID: 107053
           Summary: ones bits is not tracked and popcount is not tracked
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Keywords: missed-optimization
          Severity: enhancement
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: pinskia at gcc dot gnu.org
  Target Milestone: ---

Take:
```
void link_failure();
void f(int a)
{
    a |= 0x300;
    int b =  __builtin_popcount(a);
    if (b < 3)
        link_failure();
}
```
The if statement should be optimized away.
The reason is after the |, at least 3 bits are set in a.