[Bug target/120428] [14/15/16 regression] Suboptimal autovec involving blocked permutation and std::copy

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120428

--- Comment #10 from Jonathan Wakely <redi at gcc dot gnu.org> ---
(In reply to Jonathan Wakely from comment #6)
> The regression was caused by
> r15-3078-g6ea25c041964bf63014fcf7bb68fb1f5a0a4e123

I bisected to this commit using the code in comment 2. It looks like the code
in comment 0 does not change with that commit, but maybe the problem was just
latent until the library change in
r15-4475-g7ed561f63e7955df4d194669998176df5ef47803