diff options
Diffstat (limited to 'lib/compiler/src/beam_dead.erl')
| -rw-r--r-- | lib/compiler/src/beam_dead.erl | 71 |
1 files changed, 7 insertions, 64 deletions
diff --git a/lib/compiler/src/beam_dead.erl b/lib/compiler/src/beam_dead.erl index 1365f3d20a..5f12a98f09 100644 --- a/lib/compiler/src/beam_dead.erl +++ b/lib/compiler/src/beam_dead.erl @@ -131,10 +131,9 @@ -import(lists, [mapfoldl/3,reverse/1]). module({Mod,Exp,Attr,Fs0,_}, _Opts) -> - Fs1 = [split_blocks(F) || F <- Fs0], - {Fs2,Lc1} = beam_clean:clean_labels(Fs1), - {Fs,Lc} = mapfoldl(fun function/2, Lc1, Fs2), - %%{Fs,Lc} = {Fs2,Lc1}, + {Fs1,Lc1} = beam_clean:clean_labels(Fs0), + {Fs,Lc} = mapfoldl(fun function/2, Lc1, Fs1), + %%{Fs,Lc} = {Fs1,Lc1}, {ok,{Mod,Exp,Attr,Fs,Lc}}. function({function,Name,Arity,CLabel,Is0}, Lc0) -> @@ -144,9 +143,9 @@ function({function,Name,Arity,CLabel,Is0}, Lc0) -> %% Initialize label information with the code %% for the func_info label. Without it, a register %% may seem to be live when it is not. - [{label,L},{func_info,_,_,_}=FI|_] = Is1, + [{label,L}|FiIs] = Is1, D0 = beam_utils:empty_label_index(), - D = beam_utils:index_label(L, [FI], D0), + D = beam_utils:index_label(L, FiIs, D0), %% Optimize away dead code. {Is2,Lc} = forward(Is1, Lc0), @@ -160,62 +159,6 @@ function({function,Name,Arity,CLabel,Is0}, Lc0) -> erlang:raise(Class, Error, Stack) end. -%% We must split the basic block when we encounter instructions with labels, -%% such as catches and BIFs. All labels must be visible outside the blocks. - -split_blocks({function,Name,Arity,CLabel,Is0}) -> - Is = split_blocks(Is0, []), - {function,Name,Arity,CLabel,Is}. - -split_blocks([{block,Bl}|Is], Acc0) -> - Acc = split_block(Bl, [], Acc0), - split_blocks(Is, Acc); -split_blocks([I|Is], Acc) -> - split_blocks(Is, [I|Acc]); -split_blocks([], Acc) -> reverse(Acc). - -split_block([{set,[R],[_,_,_]=As,{bif,is_record,{f,Lbl}}}|Is], Bl, Acc) -> - %% is_record/3 must be translated by beam_clean; therefore, - %% it must be outside of any block. - split_block(Is, [], [{bif,is_record,{f,Lbl},As,R}|make_block(Bl, Acc)]); -split_block([{set,[R],As,{bif,N,{f,Lbl}=Fail}}|Is], Bl, Acc) when Lbl =/= 0 -> - split_block(Is, [], [{bif,N,Fail,As,R}|make_block(Bl, Acc)]); -split_block([{set,[R],As,{alloc,Live,{gc_bif,N,{f,Lbl}=Fail}}}|Is], Bl, Acc) - when Lbl =/= 0 -> - split_block(Is, [], [{gc_bif,N,Fail,Live,As,R}|make_block(Bl, Acc)]); -split_block([{set,[R],[],{'catch',L}}|Is], Bl, Acc) -> - split_block(Is, [], [{'catch',R,L}|make_block(Bl, Acc)]); -split_block([I|Is], Bl, Acc) -> - split_block(Is, [I|Bl], Acc); -split_block([], Bl, Acc) -> make_block(Bl, Acc). - -make_block([], Acc) -> Acc; -make_block([{set,[D],Ss,{bif,Op,Fail}}|Bl]=Bl0, Acc) -> - %% If the last instruction in the block is a comparison or boolean operator - %% (such as '=:='), move it out of the block to facilitate further - %% optimizations. - Arity = length(Ss), - case erl_internal:comp_op(Op, Arity) orelse - erl_internal:new_type_test(Op, Arity) orelse - erl_internal:bool_op(Op, Arity) of - false -> - [{block,reverse(Bl0)}|Acc]; - true -> - I = {bif,Op,Fail,Ss,D}, - case Bl =:= [] of - true -> [I|Acc]; - false -> [I,{block,reverse(Bl)}|Acc] - end - end; -make_block([{set,[Dst],[Src],move}|Bl], Acc) -> - %% Make optimization of {move,Src,Dst}, {jump,...} possible. - I = {move,Src,Dst}, - case Bl =:= [] of - true -> [I|Acc]; - false -> [I,{block,reverse(Bl)}|Acc] - end; -make_block(Bl, Acc) -> [{block,reverse(Bl)}|Acc]. - %% 'move' instructions outside of blocks may thwart the jump optimizer. %% Move them back into the block. @@ -406,7 +349,7 @@ backward([{test,Op,{f,To0},Live,Ops0,Dst}|Is], D, Acc) -> end, I = {test,Op,{f,To},Live,Ops0,Dst}, backward(Is, D, [I|Acc]); -backward([{kill,_}=I|Is], D, [Exit|_]=Acc) -> +backward([{kill,_}=I|Is], D, [{line,_},Exit|_]=Acc) -> case beam_jump:is_exit_instruction(Exit) of false -> backward(Is, D, [I|Acc]); true -> backward(Is, D, Acc) @@ -471,7 +414,7 @@ shortcut_fail_label(To0, Reg, Val, D) -> shortcut_boolean_label(To0, Reg, Bool0, D) when is_boolean(Bool0) -> case beam_utils:code_at(To0, D) of - [{bif,'not',_,[Reg],Reg},{jump,{f,To}}|_] -> + [{line,_},{bif,'not',_,[Reg],Reg},{jump,{f,To}}|_] -> Bool = not Bool0, {shortcut_select_label(To, Reg, Bool, D),Bool}; _ -> |