<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/78438>78438</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Missed optimization: (1/(y+1))/2 => 0
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            new issue
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          ZY546
      </td>
    </tr>
</table>

<pre>
    https://godbolt.org/z/exPx5Th8G

```cpp
void func(int x, int y){
    a=2;
    b=2;
 c=(1/(y+1))/a;
}
```

Clang -O3:
```asm
func(int, int): # @func(int, int)
        mov     dword ptr [rip + a], 2
        mov     dword ptr [rip + b], 2
        lea     ecx, [rsi + 2]
        xor     eax, eax
        cmp     ecx, 2
        ja .LBB0_2
        inc     esi
        mov     eax, esi
 shr     eax, 31
        add     eax, esi
        sar eax
.LBB0_2:                                # %select.end
        mov dword ptr [rip + c], eax
        ret
```

But the code below works as expected:
```cpp
void func2(int x, int y){
    a=2;
 //b=2;
    c=(1/(y+1))/a;
}
```

Clang -O3:
```asm
func2(int, int):                             # @func2(int, int)
        mov     dword ptr [rip + a], 2
        mov     dword ptr [rip + c], 0
        ret
```
</pre>
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