<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/72831>72831</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Wrong code at -O2 on x86_64-linux_gnu(recent regression)
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
      </td>
    </tr>

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

    <tr>
      <th>Reporter</th>
      <td>
          shao-hua-li
      </td>
    </tr>
</table>

<pre>
    Clang at -O2 produces the wrong code.

Bisected to d53b3df570e359d175d6e7a825ad1a02f9bc80a3, which was committed by @dc03 

Compiler explorer: https://godbolt.org/z/bcTzEb9zh

```console
% cat a.c
int printf(const char *, ...);
long a = 3, b = 3, c = 1;
unsigned char d;
int g;
static short h = -19730;
int *k = &g;
int l(long m, long *n) {
  for (long e = 0; e < b; e++)
    for (long f = 0; f < a; f++)
      if (1 == m) {
        *n = f;
        return 1;
 }
  return 0;
}
int o(long m) {
  long i;
  int j = l(m, &i);
  return j;
}
int main() {
  d = -24;
  char p[2];
 int e = 0;
  for (; e < 2; e++)
    p[o(c) + 7 + (int)c + d + h + 19489 + e] = 2;
  *k = p[0];
  printf("%d\n", g);
}
% clang -O0 a.c && ./a.out
2
% clang -O2 a.c && ./a.out
0
%
```
</pre>
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