[Bug target/126747] New: aarch64: wrong code with -Os

[kristerw at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126747

            Bug ID: 126747
           Summary: aarch64: wrong code with -Os
           Product: gcc
           Version: 17.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: kristerw at gcc dot gnu.org
            Blocks: 118443
  Target Milestone: ---
            Target: aarch64-unknown-linux-gnu

The test below fails when compiled for AArch64 with -Os:

volatile int c[2];

[[gnu::noipa]] int
foo (unsigned x, unsigned y)
{
  unsigned r = x * y;
  int t = 0;
  if (c[0]) { int u = 0; if (x != 0) u = (r / x != y); t += u; }
  if (c[1]) { int u = 0; if (x != 0) u = (r / x != y); t += u; }
  return t;
}

int main()
{
  c[0] = 1;
  c[1] = 1;
  if (foo(1,1))
    __builtin_abort();
  return 0;
}


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=118443
[Bug 118443] [Meta bug] Bugs triggered by and blocking more smtgcc testing