https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118902
Bug ID: 118902
Summary: missing predicated VN due to Canonical order of
comparison with invariant
Product: gcc
Version: 15.0
Status: UNCONFIRMED
Keywords: missed-optimization
Severity: enhancement
Priority: P3
Component: tree-optimization
Assignee: pinskia at gcc dot gnu.org
Reporter: pinskia at gcc dot gnu.org
Target Milestone: ---
Take:
```
void foo(int);
void l(int**);
int f1(int j, int t)
{
int p = 0;
int *a = &p;
l(&a);
if (a == &p)
return 0;
for(int i = 0; i < j; i++)
{
if (a == &p) foo(p);
}
return 0;
}
```
We should be able to optimize out the call to foo because in the first
iteration of the loop, a cannot be equal to `&p`.
But we don't record the predicate VN because the comparison is:
`&p == a.0_1`.
The patch which I put in PR 118867 fixes this.
