[Bug tree-optimization/78821] GCC7: Copying whole 32 bits structure field by field not optimised into copying whole 32 bits at once

[ubizjak at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78821

--- Comment #18 from Uroš Bizjak <ubizjak at gmail dot com> ---
Maybe related to bswap optimization is also:

typedef __SIZE_TYPE__ size_t;

void baz (char *buf, unsigned int data)
{
  buf[0] = data >> 8;
  buf[1] = data;
}

which currently generates (-O2 -march=haswell)

        rolw    $8, %si
        movw    %si, (%rdi)

but could use "movbew %si, (%rdi)".