https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111864
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Ever confirmed|0 |1
Last reconfirmed| |2023-10-18
Keywords| |needs-bisection
Status|UNCONFIRMED |NEW
Target Milestone|14.0 |12.4
Summary|[14 Regression] Dead Code |[12/13/14 Regression] Dead
|Elimination Regression |Code Elimination Regression
|since r14-4038-gb975c0dc3be |
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Confirmed but this is just happened to be a side effect.
In forwprop1 we can change:
```
# iftmp.5_11 = PHI <1(3), 0(4)>
_4 = iftmp.5_11 <= 0;
_5 = (short int) _4;
_25 = (int) _4;
_26 = _25 << 5;
_29 = (short int) _4;
_27 = _29 << 5;
_6 = (int) _27;
if (_27 != 0)
```
Into just:
```
# iftmp.5_11 = PHI <1(3), 0(4)>
if (iftmp.5_11 <= 0)
```
And then ethread is able to thread through that bb.
You get the same missed optimization with removing the call to a.
that is changing:
```
short v = a((g && p(t)) <= 0, 5);
```
to
```
short v = ((g && p(t)) <= 0);
```
Which then becomes a regression between GCC 11 and GCC 12.
