<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/91704>91704</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            performance issue of loop execution with llvm-19-init
        </td>
    </tr>

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

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

    <tr>
      <th>Reporter</th>
      <td>
          bi6c
      </td>
    </tr>
</table>

<pre>
    ```c
#include <stdint.h>

static uint32_t a;

int main (int argc, char* argv[])
{
    for (a = 5; (a > 1); a -= 6)
    { 
        
    }
}
```

Hello, we are using clang to compile the above code in Ubuntu 22.04.3 LTS.
We found that there is about 4 times difference of execution time when we compile it with llvmorg-13.0.0 and llvmorg-19-init. The execution time result is shown below.

```
~/compiler-builds/llvmorg-13.0.0_build/bin/clang test.c -o exec1
time ./exec1

real    0m0.390s
user    0m0.390s
sys 0m0.000s

~/compiler-builds/llvmorg-19-init_build/bin/clang test.c -o exec2
time ./exec2

real    0m2.085s
user    0m2.084s
sys 0m0.000s
```
</pre>
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