http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51005
--- Comment #2 from vries at gcc dot gnu.org 2011-11-07 10:05:03 UTC --- Created attachment 25733 --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=25733 possible patch This patch brings the computation time back down: ... $ time gcc src/gcc/testsuite/gcc.c-torture/compile/20001226-1.c -S -O2 -ftree-tail-merge real 0m35.600s user 0m35.210s sys 0m0.270s ... The patch delegates the updating of the vops to TODO_update_ssa_only_virtuals. That way, the dominators don't need to be updated after every replacement, just after every iteration.
