https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114704
Bug ID: 114704
Summary: Missed optimization : eliminate store if the value is
known in all predecessors
Product: gcc
Version: 14.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: xxs_chy at outlook dot com
Target Milestone: ---
Godbolt link: https://godbolt.org/z/KEeGTM49E
For code like:
```
void src(int *p){
if(*p == 0)
goto then;
else {
dummy();
if(*p == 0)
goto then;
else
return;
}
then:
*p = 0; // *p is already 0, it's dead now
}
```
In then basic block, *p is known to be 0 in all predecessors, thus the store
"*p = 0" is redundant.
