[Bug tree-optimization/111572] New: Wrong code at -O2 on x86_64-linux-gnu since r14-301-gf2d6beb7a4d

[shaohua.li at inf dot ethz.ch]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111572

            Bug ID: 111572
           Summary: Wrong code at -O2 on x86_64-linux-gnu since
                    r14-301-gf2d6beb7a4d
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: shaohua.li at inf dot ethz.ch
                CC: jh at suse dot cz
  Target Milestone: ---

gcc at -O2 produces the wrong code.

Bisected to r14-301-gf2d6beb7a4d

Compiler explorer: https://godbolt.org/z/reETd3ee4

$ cat a.c
int printf(const char *, ...);
int a, b = -8, e, f, h;
char c, d, g;
static int i(long k) {
  e = 8;
  for (; e; e = f) {
    d = 6;
    for (; d<7; d++) {
      unsigned char j = 0;
      for (; (unsigned char)(1 + k) + j <= 3; j++)
        printf("%u\n", (unsigned char)(1 + k) + j);
    }
    for (; g; g++)
      ;
  }
  return 0;
}
int main() {
  h = 26 & b;
  i((short)(h - 65557) + 65535);
}
$
$ gcc -O0 a.c && ./a.out
3
$ gcc -O2 a.c && ./a.out
3
3
3
3
(Truncated)
$