[Bug c++/90178] [9 Regression] Missed optimization: duplicated terminal basic block with -mavx

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90178

--- Comment #5 from H.J. Lu <hjl.tools at gmail dot com> ---
zveroupper pass drops:

(insn 36 37 51 8 (use (reg/i:DI 0 ax)) "x.i":8:1 -1
     (nil))