diff options
Diffstat (limited to 'lib/compiler/src/beam_jump.erl')
-rw-r--r-- | lib/compiler/src/beam_jump.erl | 131 |
1 files changed, 89 insertions, 42 deletions
diff --git a/lib/compiler/src/beam_jump.erl b/lib/compiler/src/beam_jump.erl index b952139f2c..5bfaa41b7d 100644 --- a/lib/compiler/src/beam_jump.erl +++ b/lib/compiler/src/beam_jump.erl @@ -127,7 +127,7 @@ %%% on the program state. %%% --import(lists, [reverse/1,reverse/2,foldl/3,dropwhile/2]). +-import(lists, [reverse/1,reverse/2,foldl/3]). module({Mod,Exp,Attr,Fs0,Lc}, _Opt) -> Fs = [function(F) || F <- Fs0], @@ -152,20 +152,26 @@ function({function,Name,Arity,CLabel,Asm0}) -> share(Is0) -> %% We will get more sharing if we never fall through to a label. Is = eliminate_fallthroughs(Is0, []), - share_1(Is, dict:new(), [], []). + share_1(Is, #{}, [], []). share_1([{label,_}=Lbl|Is], Dict, [], Acc) -> share_1(Is, Dict, [], [Lbl|Acc]); share_1([{label,L}=Lbl|Is], Dict0, Seq, Acc) -> - case dict:find(Seq, Dict0) of + case maps:find(Seq, Dict0) of error -> - Dict = dict:store(Seq, L, Dict0), + Dict = maps:put(Seq, L, Dict0), share_1(Is, Dict, [], [Lbl|Seq ++ Acc]); {ok,Label} -> share_1(Is, Dict0, [], [Lbl,{jump,{f,Label}}|Acc]) end; share_1([{func_info,_,_,_}=I|Is], _, [], Acc) -> reverse(Is, [I|Acc]); +share_1([{'try',_,_}=I|Is], Dict0, Seq, Acc) -> + Dict = clean_non_sharable(Dict0), + share_1(Is, Dict, [I|Seq], Acc); +share_1([{try_case,_}=I|Is], Dict0, Seq, Acc) -> + Dict = clean_non_sharable(Dict0), + share_1(Is, Dict, [I|Seq], Acc); share_1([I|Is], Dict, Seq, Acc) -> case is_unreachable_after(I) of false -> @@ -174,6 +180,24 @@ share_1([I|Is], Dict, Seq, Acc) -> share_1(Is, Dict, [I], Acc) end. +clean_non_sharable(Dict) -> + %% We are passing in or out of a 'try' block. Remove + %% sequences that should not shared over the boundaries + %% of a 'try' block. Since the end of the sequence must match, + %% the only possible match between a sequence outside and + %% a sequence inside the 'try' block is a sequence that ends + %% with an instruction that causes an exception. Any sequence + %% that causes an exception must contain a line/1 instruction. + maps:filter(fun(K, _V) -> sharable_with_try(K) end, Dict). + +sharable_with_try([{line,_}|_]) -> + %% This sequence may cause an exception and may potentially + %% match a sequence on the other side of the 'try' block + %% boundary. + false; +sharable_with_try([_|Is]) -> + sharable_with_try(Is); +sharable_with_try([]) -> true. %% Eliminate all fallthroughs. Return the result reversed. @@ -244,13 +268,13 @@ extract_seq_1(_, _) -> no. -record(st, {fc, %Label for function class errors. entry, %Entry label (must not be moved). mlbl, %Moved labels. - labels %Set of referenced labels. + labels :: cerl_sets:set() %Set of referenced labels. }). opt([{label,Fc}|_]=Is0, CLabel) -> Lbls = initial_labels(Is0), find_fixpoint(fun(Is) -> - St = #st{fc=Fc,entry=CLabel,mlbl=dict:new(), + St = #st{fc=Fc,entry=CLabel,mlbl=#{}, labels=Lbls}, opt(Is, [], St) end, Is0). @@ -295,24 +319,29 @@ opt([{test,_,{f,_}=Lbl,_,_,_}=I|Is], Acc, St) -> opt(Is, [I|Acc], label_used(Lbl, St)); opt([{select,_,_R,Fail,Vls}=I|Is], Acc, St) -> skip_unreachable(Is, [I|Acc], label_used([Fail|Vls], St)); -opt([{label,L}=I|Is], Acc, #st{entry=L}=St) -> - %% NEVER move the entry label. - opt(Is, [I|Acc], St); -opt([{label,L1},{jump,{f,L2}}=I|Is], [Prev|Acc], St0) -> - St = St0#st{mlbl=dict:append(L2, L1, St0#st.mlbl)}, - opt([Prev,I|Is], Acc, label_used({f,L2}, St)); opt([{label,Lbl}=I|Is], Acc, #st{mlbl=Mlbl}=St0) -> - case dict:find(Lbl, Mlbl) of + case maps:find(Lbl, Mlbl) of {ok,Lbls} -> %% Essential to remove the list of labels from the dictionary, %% since we will rescan the inserted labels. We MUST rescan. - St = St0#st{mlbl=dict:erase(Lbl, Mlbl)}, + St = St0#st{mlbl=maps:remove(Lbl, Mlbl)}, insert_labels([Lbl|Lbls], Is, Acc, St); error -> opt(Is, [I|Acc], St0) end; -opt([{jump,{f,Lbl}},{label,Lbl}=I|Is], Acc, St) -> - opt([I|Is], Acc, St); -opt([{jump,Lbl}=I|Is], Acc, St) -> +opt([{jump,{f,_}=X}|[{label,_},{jump,X}|_]=Is], Acc, St) -> + opt(Is, Acc, St); +opt([{jump,{f,Lbl}}|[{label,Lbl}|_]=Is], Acc, St) -> + opt(Is, Acc, St); +opt([{jump,{f,L}=Lbl}=I|Is], Acc0, #st{mlbl=Mlbl0}=St0) -> + %% All labels before this jump instruction should now be + %% moved to the location of the jump's target. + {Lbls,Acc} = collect_labels(Acc0, St0), + St = case Lbls of + [] -> St0; + [_|_] -> + Mlbl = maps_append_list(L, Lbls, Mlbl0), + St0#st{mlbl=Mlbl} + end, skip_unreachable(Is, [I|Acc], label_used(Lbl, St)); %% Optimization: quickly handle some common instructions that don't %% have any failure labels and where is_unreachable_after(I) =:= false. @@ -334,14 +363,20 @@ opt([I|Is], Acc, #st{labels=Used0}=St0) -> end; opt([], Acc, #st{fc=Fc,mlbl=Mlbl}) -> Code = reverse(Acc), - case dict:find(Fc, Mlbl) of + case maps:find(Fc, Mlbl) of {ok,Lbls} -> insert_fc_labels(Lbls, Mlbl, Code); error -> Code end. +maps_append_list(K,Vs,M) -> + case M of + #{K:=Vs0} -> M#{K:=Vs0++Vs}; % same order as dict + _ -> M#{K => Vs} + end. + insert_fc_labels([L|Ls], Mlbl, Acc0) -> Acc = [{label,L}|Acc0], - case dict:find(L, Mlbl) of + case maps:find(L, Mlbl) of error -> insert_fc_labels(Ls, Mlbl, Acc); {ok,Lbls} -> @@ -349,6 +384,17 @@ insert_fc_labels([L|Ls], Mlbl, Acc0) -> end; insert_fc_labels([], _, Acc) -> Acc. +collect_labels(Is, #st{entry=Entry}) -> + collect_labels_1(Is, Entry, []). + +collect_labels_1([{label,Entry}|_]=Is, Entry, Acc) -> + %% Never move the entry label. + {Acc,Is}; +collect_labels_1([{label,L}|Is], Entry, Acc) -> + collect_labels_1(Is, Entry, [L|Acc]); +collect_labels_1(Is, _Entry, Acc) -> + {Acc,Is}. + %% label_defined(Is, Label) -> true | false. %% Test whether the label Label is defined at the start of the instruction %% sequence, possibly preceeded by other label definitions. @@ -394,7 +440,7 @@ skip_unreachable([], Acc, St) -> %% Add one or more label to the set of used labels. -label_used({f,L}, St) -> St#st{labels=gb_sets:add(L, St#st.labels)}; +label_used({f,L}, St) -> St#st{labels=cerl_sets:add_element(L,St#st.labels)}; label_used([H|T], St0) -> label_used(T, label_used(H, St0)); label_used([], St) -> St; label_used(_Other, St) -> St. @@ -402,7 +448,7 @@ label_used(_Other, St) -> St. %% Test if label is used. is_label_used(L, St) -> - gb_sets:is_member(L, St#st.labels). + cerl_sets:is_element(L, St#st.labels). %% is_unreachable_after(Instruction) -> boolean() %% Test whether the code after Instruction is unreachable. @@ -432,29 +478,29 @@ is_exit_instruction(_) -> false. %% (including inside blocks). is_label_used_in(Lbl, Is) -> - is_label_used_in_1(Is, Lbl, gb_sets:empty()). + is_label_used_in_1(Is, Lbl, cerl_sets:new()). is_label_used_in_1([{block,Block}|Is], Lbl, Empty) -> - lists:any(fun(I) -> is_label_used_in_2(I, Lbl) end, Block) + lists:any(fun(I) -> is_label_used_in_block(I, Lbl) end, Block) orelse is_label_used_in_1(Is, Lbl, Empty); is_label_used_in_1([I|Is], Lbl, Empty) -> Used = ulbl(I, Empty), - gb_sets:is_member(Lbl, Used) orelse is_label_used_in_1(Is, Lbl, Empty); + cerl_sets:is_element(Lbl, Used) orelse is_label_used_in_1(Is, Lbl, Empty); is_label_used_in_1([], _, _) -> false. -is_label_used_in_2({set,_,_,Info}, Lbl) -> +is_label_used_in_block({set,_,_,Info}, Lbl) -> case Info of - {bif,_,{f,F}} -> F =:= Lbl; - {alloc,_,{gc_bif,_,{f,F}}} -> F =:= Lbl; + {bif,_,{f,F}} -> F =:= Lbl; + {alloc,_,{gc_bif,_,{f,F}}} -> F =:= Lbl; {alloc,_,{put_map,_,{f,F}}} -> F =:= Lbl; - {'catch',{f,F}} -> F =:= Lbl; - {alloc,_,_} -> false; - {put_tuple,_} -> false; - {get_tuple_element,_} -> false; - {set_tuple_element,_} -> false; {get_map_elements,{f,F}} -> F =:= Lbl; - {line,_} -> false; - _ when is_atom(Info) -> false + {'catch',{f,F}} -> F =:= Lbl; + {alloc,_,_} -> false; + {put_tuple,_} -> false; + {get_tuple_element,_} -> false; + {set_tuple_element,_} -> false; + {line,_} -> false; + _ when is_atom(Info) -> false end. %% remove_unused_labels(Instructions0) -> Instructions @@ -467,13 +513,10 @@ remove_unused_labels(Is) -> rem_unused(Is, Used, []). rem_unused([{label,Lbl}=I|Is0], Used, [Prev|_]=Acc) -> - case gb_sets:is_member(Lbl, Used) of + case cerl_sets:is_element(Lbl, Used) of false -> Is = case is_unreachable_after(Prev) of - true -> - dropwhile(fun({label,_}) -> false; - (_) -> true - end, Is0); + true -> drop_upto_label(Is0); false -> Is0 end, rem_unused(Is, Used, Acc); @@ -492,7 +535,11 @@ initial_labels([{line,_}|Is], Acc) -> initial_labels([{label,Lbl}|Is], Acc) -> initial_labels(Is, [Lbl|Acc]); initial_labels([{func_info,_,_,_},{label,Lbl}|_], Acc) -> - gb_sets:from_list([Lbl|Acc]). + cerl_sets:from_list([Lbl|Acc]). + +drop_upto_label([{label,_}|_]=Is) -> Is; +drop_upto_label([_|Is]) -> drop_upto_label(Is); +drop_upto_label([]) -> []. %% ulbl(Instruction, UsedGbSet) -> UsedGbSet' %% Update the gb_set UsedGbSet with any function-local labels @@ -536,10 +583,10 @@ ulbl({get_map_elements,Lbl,_Src,_List}, Used) -> ulbl(_, Used) -> Used. mark_used({f,0}, Used) -> Used; -mark_used({f,L}, Used) -> gb_sets:add(L, Used). +mark_used({f,L}, Used) -> cerl_sets:add_element(L, Used). mark_used_list([{f,L}|T], Used) -> - mark_used_list(T, gb_sets:add(L, Used)); + mark_used_list(T, cerl_sets:add_element(L, Used)); mark_used_list([_|T], Used) -> mark_used_list(T, Used); mark_used_list([], Used) -> Used. |