[Bug rtl-optimization/98863] WRF with LTO consumes a lot of memory in split2 pass

[rguenth at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98863

--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> ---
df-problems.c:228 (df_rd_alloc)                        702M:  6.9%      705M   
   18M:  0.7%          0           0       heap
df-problems.c:509 (df_rd_transfer_function)           3709M: 36.6%     3709M   
  188M:  7.1%          0           0       heap
df-problems.c:227 (df_rd_alloc)                       4417M: 43.6%     4417M   
  111M:  4.2%          0           0       heap

that's not 20Gb but quite a bit.  For GC memory complete unrolling is the
biggest offender (but "only" 500MB).