陳韋任 <che...@iis.sinica.edu.tw> writes: >> That documentation is out of date. The CFG is now retained through most >> of the RTL passes. > > You said "through most of the RTLpasses". And I found the CFG > is freed before other passes in gcc/passes.c. > > NEXT_PASS (pass_free_cfg); > NEXT_PASS (pass_machine_reorg); > NEXT_PASS (pass_cleanup_barriers); > NEXT_PASS (pass_delay_slots); > NEXT_PASS (pass_split_for_shorten_branches); > NEXT_PASS (pass_convert_to_eh_region_ranges); > NEXT_PASS (pass_shorten_branches); > NEXT_PASS (pass_set_nothrow_function_flags); > NEXT_PASS (pass_final); > > Is the CFG the same as the one in the assembly? I mean > if I analysis the assembly and contruct the CFG back, they > are the same?
The machine reorg pass in particular can change anything, and may change the CFG. The delay slots pass may also change the CFG. It depends on your particular target. Ian
