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From: "pinskia at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/114787] [13/14 Regression] wrong code at -O1
 on x86_64-linux-gnu (the generated code hangs)
Date: Sat, 20 Apr 2024 23:37:24 +0000
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X-Bugzilla-Component: tree-optimization
X-Bugzilla-Version: 14.0
X-Bugzilla-Keywords: needs-bisection, wrong-code
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D114787

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
The first difference (in GCC 13) with/without -fdump-tree-all-all comes from
cunroll:



Broken:
```
Loop 3 iterates 2 times.
Loop 3 iterates at most 1 times.
Loop 3 likely iterates at most 1 times.
Analyzing # of iterations of loop 3
  exit condition [2, + , 4294967295] !=3D 0
  bounds on difference of bases: -2 ... -2
  result:
    # of iterations 2, bounded by 2
Removed pointless exit: if (ivtmp_43 !=3D 0)
```

Working:
```
Loop 3 iterates 2 times.
Loop 3 iterates at most 2 times.
Loop 3 likely iterates at most 2 times.
```=