[Bug rtl-optimization/69896] [6 Regression] wrong code with -frename-registers @ x64_64

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69896

--- Comment #8 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 37809
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=37809&action=edit
gcc6-pr69896.patch

Ah, managed to reproduce.  I have one patch and one partial incomplete one.
It doesn't make any sense to me to use TYPE_VECTOR_SUBPARTS () == 1 vectors
for the computation if it is the widest supported vector type, we should just
use the element type instead.  So that is what this patch does.