[Bug debug/60438] [4.9 Regression] dwarf2cfi :2239 still assert,not the same cause as PR 59575

[jakub at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=60438

--- Comment #30 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to Richard Henderson from comment #29)
> linj, that hunk is required.  It's easy to produce a difference ICE
> without it.  I believe that even this pr's test case with -fno-crossjumping
> is enough to trigger the different ICE.
> 
> Jakub, it's way more difficult to merge these notes than one might think.
> Primarily because CSA hasn't done full CFA analysis.  It might be possible
> to merge two REG_CFA_ADJUST_CFA relatively easily.  But I'm not really sure
> how common that is.  Certainly it didn't happen in this test case at all.
> 
> I think at this point, any such optimization will have to wait for stage1.

I'll try to gather some statistics on the combine-stack-adj.c hunk alone
tomorrow.