[Bug tree-optimization/65077] [4.9/5 Regression] memcpy generates incorrect code with floating point numbers and -O1

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65077

--- Comment #10 from Richard Biener <rguenth at gcc dot gnu.org> ---
Created attachment 34781
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=34781&action=edit
untested patch

Patch which fixes the testcase and doesn't regress the vectorization testcase
from PR37021.