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-rw-r--r--lib/compiler/src/beam_jump.erl114
1 files changed, 80 insertions, 34 deletions
diff --git a/lib/compiler/src/beam_jump.erl b/lib/compiler/src/beam_jump.erl
index b952139f2c..80b2998ddc 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.
@@ -432,17 +478,17 @@ 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;
@@ -452,7 +498,6 @@ is_label_used_in_2({set,_,_,Info}, Lbl) ->
{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
end.
@@ -467,13 +512,10 @@ 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 +534,11 @@ 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 +582,10 @@ 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.