[Bug middle-end/127860] expand_vec_perm_const reduces the selector by the result length for a VEC_PERM_EXPR with wider inputs (latent wrong code)

[igor at tachyum dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=127860

--- Comment #2 from Igor Shevlyakov <igor at tachyum dot com> ---
patch is posted:

https://gcc.gnu.org/pipermail/gcc-patches/2026-October/734384.html