[Bug middle-end/32667] block copy with exact overlap is expanded as memcpy

[post+gcc at ralfj dot de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=32667

--- Comment #48 from post+gcc at ralfj dot de ---
> Note, clang makes the same assumption apparently (while MSVC emits rep movs inline and ICC either that, or calls _intel_fast_memcpy).

MSVC does the same thing as clang and GCC, if godbolt is to be trusted:
https://rust.godbolt.org/z/o7TevfvcY