[Bug target/64306] [SH] Improve unaligned loads and stores

[olegendo at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64306

--- Comment #1 from Oleg Endo <olegendo at gcc dot gnu.org> ---
If the alignment/offset of an unaligned 32 bit store is known to be 16 bit, it
can be done with something like:
        mov     r5,r0
        mov.w   r0,@({0|2},r4)
        shlr16  r0
        mov.w   r0,@({2|0},r4)