https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123456
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Blocks| |85316
Ever confirmed|0 |1
Severity|normal |enhancement
Last reconfirmed| |2026-01-08
Status|UNCONFIRMED |NEW
--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
n_38 = 1 << l_6(D);
When visited with a range for l_6(D) of [4, INF];
Should produce a range of `[-INF,-INF], [1<<4, INF]`
So a reduced testcase:
```
int f(int l)
{
// if (l >= (int)sizeof(int)*8) return 0;
if (l <= 4) return 0;
int t = 1 << l;
return (t == 0) + t;
}
```
This should reduce down to `if (l > 4) return 1 << l; else return 0;`
We handle it correctly for `1u`.
Referenced Bugs:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85316
[Bug 85316] [meta-bug] VRP range propagation missed cases
