[Bug target/14907] bogus sign/zero extension when relaying parameters with regparm

[hjl.tools at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=14907

--- Comment #7 from H.J. Lu <hjl.tools at gmail dot com> ---
Created attachment 59467
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=59467&action=edit
A patch

I am testing this.