[Bug target/65787] [5 Regression] Miscompile due to bad vector swap optimization for little endian

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65787

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Though, len is used just in one place, so perhaps even better just remove the
{}s and use 
      if (XVECLEN (op, 0) != 2)
        return 0;
and drop len variable alltogether, it will be more readable that way.