<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/72855>72855</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            Wrong code at -O1 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 -O1 produces the wrong code.

Bisected to 63917e1975bd69ef4084f02d378b0b920046be3a, which was committed by @igogo-x86 

Compiler explorer: https://godbolt.org/z/jdPPzP3P6

```console
% cat a.c
int printf(const char *, ...);
int a;
int *g = &a, *m = &a, *n = &a;
short o;
int p(char *b, long c, long *d) {
  char *e = b;
 long f = *d;
  for (; c && f; --c, ++f, ++e)
    ;
  return e - b;
}
int t(long h, long i) {
  char j;
  long k[] = {i};
  int l = p(&j, h, k);
  return l;
}
long q(int *r) {
  *m = 4;
 for (;;)
    for (; *r >= 0;) {
      *g = *n % 5 == 1;
      for (;;)
        for (; t(*n + 5, 3124342948) <= 5;)
          return 0;
    }
}
int main() {
  int s = a;
  q(&s);
 printf("%d\n", o);
}
%
% clang -O0 -fsanitize=address,undefined a.c && ./a.out
0
% clang -O1 a.c && ./a.out
Timeout
%
```
</pre>
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