https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122678
Bug ID: 122678
Summary: simple_dce_from_worklist does not handle semi-simple
cycles
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Keywords: missed-optimization
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: pinskia at gcc dot gnu.org
Target Milestone: ---
testcase:
```
int f(int a)
{
int b = a;
for(int i = 0; i < 10; i++)
a |= b;
return b | a;
}
```
yes this is simplified testcase but ccp was able to do this in GCC 13 but after
the move over to simple_dce_from_worklist in r14-569-g21e2ef2dc25de3, it is not
able to any more.
This was also noticed in https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122663#c9
.
So I thought I would file a bug with a testcase :).
