diff options
| -rw-r--r-- | lib/compiler/src/beam_ssa_opt.erl | 43 |
1 files changed, 19 insertions, 24 deletions
diff --git a/lib/compiler/src/beam_ssa_opt.erl b/lib/compiler/src/beam_ssa_opt.erl index 2bd3612c06..355d2d060d 100644 --- a/lib/compiler/src/beam_ssa_opt.erl +++ b/lib/compiler/src/beam_ssa_opt.erl @@ -249,22 +249,14 @@ fdb_update(Caller, Callee, FuncDb) -> FuncDb#{ Caller => CallerVertex#func_info{out=Calls}, Callee => CalleeVertex#func_info{in=CalledBy} }. -%% Returns the post-order of all local calls in this module. That is, it starts -%% with the functions that don't call any others and then walks up the call -%% chain. +%% Returns the post-order of all local calls in this module. That is, +%% called functions will be ordered before the functions calling them. %% %% Functions where module-level optimization is disabled are added last in %% arbitrary order. get_call_order_po(StMap, FuncDb) -> - Leaves = maps:fold(fun(Id, #func_info{out=[]}, Acc) -> - [Id | Acc]; - (_, _, Acc) -> - Acc - end, [], FuncDb), - - Order = gco_po_1(sort(Leaves), FuncDb, [], #{}), - + Order = gco_po(FuncDb), Order ++ maps:fold(fun(K, _V, Acc) -> case is_map_key(K, FuncDb) of false -> [K | Acc]; @@ -272,20 +264,23 @@ get_call_order_po(StMap, FuncDb) -> end end, [], StMap). -gco_po_1([Id | Ids], FuncDb, Children, Seen) when not is_map_key(Id, Seen) -> - [Id | gco_po_1(Ids, FuncDb, [Id | Children], Seen#{ Id => true })]; -gco_po_1([_Id | Ids], FuncDb, Children, Seen) -> - gco_po_1(Ids, FuncDb, Children, Seen); -gco_po_1([], FuncDb, [_|_]=Children, Seen) -> - gco_po_1(gco_po_parents(Children, FuncDb), FuncDb, [], Seen); -gco_po_1([], _FuncDb, [], _Seen) -> - []. +gco_po(FuncDb) -> + All = sort(maps:keys(FuncDb)), + {RPO,_} = gco_rpo(All, FuncDb, cerl_sets:new(), []), + reverse(RPO). -gco_po_parents([Child | Children], FuncDb) -> - #{ Child := #func_info{in=Parents}} = FuncDb, - Parents ++ gco_po_parents(Children, FuncDb); -gco_po_parents([], _FuncDb) -> - []. +gco_rpo([Id|Ids], FuncDb, Seen0, Acc0) -> + case cerl_sets:is_element(Id, Seen0) of + true -> + gco_rpo(Ids, FuncDb, Seen0, Acc0); + false -> + #func_info{out=Successors} = map_get(Id, FuncDb), + Seen1 = cerl_sets:add_element(Id, Seen0), + {Acc,Seen} = gco_rpo(Successors, FuncDb, Seen1, Acc0), + gco_rpo(Ids, FuncDb, Seen, [Id|Acc]) + end; +gco_rpo([], _, Seen, Acc) -> + {Acc,Seen}. %%% %%% Trivial sub passes. |