Hello All,
I am a bit confused (or unhappy) about the current_pass variable (in GCC 4.9 svn rev.208447); I believe we have some incoherency about it. It is generally (as it used to be in previous versions of GCC) a global pointer to some opt_pass, declared in gcc/tree-pass.h line 590. It is also (and independently), a local integer in function connect_traces file gcc/bb-reorder.c line 1042. I feel that for readability reasons the local current_pass should be renamed current_pass_num in the function connect_traces. But most importantly, I find confusing the way current_pass pointer is globally set (and reset). The obvious policy seems to set current_pass to "this" before calling any virtual methods on it (notably the gate and the exec functions). However, if one use -fdump-passes program argument to gcc (i.e. to cc1), then dump_passes (from gcc/passes.c line 892) gets called. It then calls function dump_one_pass (from gcc/passes.c line 851) which does line 857 is_on = pass->has_gate ? pass->gate () : true; But in other occasions, notably in function execute_one_pass (starting at gcc/passes.c line 2153) the global current_pass is set (line 2166) before calling its gate function line 2170 gate_status = pass->has_gate ? pass->gate () : true; I believe something should be done about this, since it seems to confuse plugins (like MELT). Either we decide that current_pass is always set before calling any virtual function on it (notably the gate) or we decide that current_pass global should disappear (but then, what about the curr_statistics_hash function from gcc/statistics.c line 93 which uses it line 98)? Comments are welcome. I think we should do something about this before releasing GCC 4.9... The simplest thing would be to set current_pass in dump_one_pass.... Regards. -- Basile STARYNKEVITCH http://starynkevitch.net/Basile/ email: basile<at>starynkevitch<dot>net mobile: +33 6 8501 2359 8, rue de la Faiencerie, 92340 Bourg La Reine, France *** opinions {are only mines, sont seulement les miennes} ***
