[Bug rtl-optimization/87902] [9 Regression] Shrink-wrapping multiple conditions

[iii at linux dot ibm.com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87902

--- Comment #5 from Ilya Leoshkevich <iii at linux dot ibm.com> ---
By the time shrink-wrapping is performed, which is after LRA
(pass_thread_prologue_and_epilogue, to be precise), aren't all spilling
decisions already made?  Because if that's true, we have to be
conservative in prepare_shrink_wrap () anyway, and move down copies only
when the parameter register still contains the parameter value.