diff options
Diffstat (limited to 'lib/compiler/src/beam_dead.erl')
| -rw-r--r-- | lib/compiler/src/beam_dead.erl | 41 |
1 files changed, 26 insertions, 15 deletions
diff --git a/lib/compiler/src/beam_dead.erl b/lib/compiler/src/beam_dead.erl index f4515ba2a7..bbe607cf19 100644 --- a/lib/compiler/src/beam_dead.erl +++ b/lib/compiler/src/beam_dead.erl @@ -96,7 +96,7 @@ move_move_into_block([], Acc) -> reverse(Acc). %%% forward(Is, Lc) -> - forward(Is, gb_trees:empty(), Lc, []). + forward(Is, #{}, Lc, []). forward([{move,_,_}=Move|[{label,L}|_]=Is], D, Lc, Acc) -> %% move/2 followed by jump/1 is optimized by backward/3. @@ -115,19 +115,20 @@ forward([{label,Lbl}=LblI,{block,[{set,[Dst],[Lit],move}|BlkIs]}=Blk|Is], D, Lc, %% cannot be reached in any other way than through the select_val/3 %% instruction (i.e. there can be no fallthrough to such label and %% it cannot be referenced by, for example, a jump/1 instruction). - Block = case gb_trees:lookup({Lbl,Dst}, D) of - {value,Lit} -> {block,BlkIs}; %Safe to remove move instruction. - _ -> Blk %Must keep move instruction. - end, + Key = {Lbl,Dst}, + Block = case D of + #{Key := Lit} -> {block,BlkIs}; %Safe to remove move instruction. + _ -> Blk %Must keep move instruction. + end, forward([Block|Is], D, Lc, [LblI|Acc]); forward([{label,Lbl}=LblI|[{move,Lit,Dst}|Is1]=Is0], D, Lc, Acc) -> %% Assumption: The target labels in a select_val/3 instruction %% cannot be reached in any other way than through the select_val/3 %% instruction (i.e. there can be no fallthrough to such label and %% it cannot be referenced by, for example, a jump/1 instruction). - Is = case gb_trees:lookup({Lbl,Dst}, D) of - {value,Lit} -> Is1; %Safe to remove move instruction. - _ -> Is0 %Keep move instruction. + Is = case maps:find({Lbl,Dst}, D) of + {ok,Lit} -> Is1; %Safe to remove move instruction. + _ -> Is0 %Keep move instruction. end, forward(Is, D, Lc, [LblI|Acc]); forward([{test,is_eq_exact,_,[Same,Same]}|Is], D, Lc, Acc) -> @@ -156,11 +157,11 @@ forward([], _, Lc, Acc) -> {Acc,Lc}. update_value_dict([Lit,{f,Lbl}|T], Reg, D0) -> Key = {Lbl,Reg}, - D = case gb_trees:lookup(Key, D0) of - none -> gb_trees:insert(Key, Lit, D0); %New. - {value,inconsistent} -> D0; %Inconsistent. - {value,_} -> gb_trees:update(Key, inconsistent, D0) - end, + D = case D0 of + #{Key := inconsistent} -> D0; + #{Key := _} -> D0#{Key := inconsistent}; + _ -> D0#{Key => Lit} + end, update_value_dict(T, Reg, D); update_value_dict([], _, D) -> D. @@ -255,6 +256,16 @@ backward([{jump,{f,To}}=J|[{bif,Op,_,Ops,Reg}|Is]=Is0], D, Acc) -> catch throw:not_possible -> backward(Is0, D, [J|Acc]) end; +backward([{test,bs_start_match2,F,_,[R,_],Ctxt}=I|Is], D, + [{test,bs_match_string,F,[Ctxt,Bs]}, + {test,bs_test_tail2,F,[Ctxt,0]}|Acc0]=Acc) -> + case beam_utils:is_killed(Ctxt, Acc0, D) of + true -> + Eq = {test,is_eq_exact,F,[R,{literal,Bs}]}, + backward(Is, D, [Eq|Acc0]); + false -> + backward(Is, D, [I|Acc]) + end; backward([{test,bs_start_match2,{f,To0},Live,[Src|_]=Info,Dst}|Is], D, Acc) -> To = shortcut_bs_start_match(To0, Src, D), I = {test,bs_start_match2,{f,To},Live,Info,Dst}, @@ -459,8 +470,8 @@ count_bits_matched([{test,_,_,_,[_,Sz,U,{field_flags,_}],_}|Is], SavePoint, Bits {integer,N} -> count_bits_matched(Is, SavePoint, Bits+N*U); _ -> count_bits_matched(Is, SavePoint, Bits) end; -count_bits_matched([{test,bs_match_string,_,[_,Bits,_]}|Is], SavePoint, Bits0) -> - count_bits_matched(Is, SavePoint, Bits0+Bits); +count_bits_matched([{test,bs_match_string,_,[_,Bs]}|Is], SavePoint, Bits) -> + count_bits_matched(Is, SavePoint, Bits+bit_size(Bs)); count_bits_matched([{test,_,_,_}|Is], SavePoint, Bits) -> count_bits_matched(Is, SavePoint, Bits); count_bits_matched([{bs_save2,Reg,SavePoint}|_], {Reg,SavePoint}, Bits) -> |