https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116899
--- Comment #4 from Andrew Macleod <amacleod at redhat dot com> --- (In reply to Jakub Jelinek from comment #3) > Similarly to the other BB, enable_ranger -> gimple_ranger -> ranger_cache > does > 1000 m_workback.create (0); > 1001 m_workback.safe_grow_cleared (last_basic_block_for_fn (cfun)); > 1002 m_workback.truncate (0); > (which seems just weird, I'd expect m_workback.create > (last_basic_block_for_fn (cfun)); > Creating a large vector, filling it with zeros and then immediately > truncating is just a waste of time) and then just uses > m_workback.quick_push. That works only if no new basic blocks are created, > which the gimple-lower-bitint creates a lot (split_block in tons of places, > even manual create_basic_block). with the truncate, clearly no need for the safe growing. I think my use of the create (0); safe_grow(size); idiom dates back to a problem I once had (years ago) where "create (size)" caused me a failure down the road that was hard to debug.. and it was fixed by the ceate (0) safe_grow(size) seqeuence. , so I ended up just always doing it that way :-P I especially see no need for that safe_grow_cleared call in this case
