[Bug target/65375] poor codegen for ld[234]/st[234]

[kugan at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65375

--- Comment #2 from kugan at gcc dot gnu.org ---
aarch64-none-linux-gnu-gcc -O2 -ffast-math -unsafe-math-optimisations
-fno-split-wide-types produces :

    ld2    {v2.4s - v3.4s}, [x1]
    orr    v0.16b, v2.16b, v2.16b
    orr    v1.16b, v3.16b, v3.16b
    st2    {v0.4s - v1.4s}, [x0]
    ret