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-rw-r--r--lib/compiler/src/beam_bs.erl183
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diff --git a/lib/compiler/src/beam_bs.erl b/lib/compiler/src/beam_bs.erl
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index 15d8d687fc..0000000000
--- a/lib/compiler/src/beam_bs.erl
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@@ -1,183 +0,0 @@
-%%
-%% %CopyrightBegin%
-%%
-%% Copyright Ericsson AB 1999-2018. All Rights Reserved.
-%%
-%% Licensed under the Apache License, Version 2.0 (the "License");
-%% you may not use this file except in compliance with the License.
-%% You may obtain a copy of the License at
-%%
-%% http://www.apache.org/licenses/LICENSE-2.0
-%%
-%% Unless required by applicable law or agreed to in writing, software
-%% distributed under the License is distributed on an "AS IS" BASIS,
-%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-%% See the License for the specific language governing permissions and
-%% limitations under the License.
-%%
-%% %CopyrightEnd%
-%%
-%% Purpose: Peephole optimization of binary syntax instructions.
-
--module(beam_bs).
-
--export([module/2]).
--import(lists, [reverse/1]).
-
--spec module(beam_utils:module_code(), [compile:option()]) ->
- {'ok',beam_utils:module_code()}.
-
-module({Mod,Exp,Attr,Fs0,Lc}, _Opt) ->
- Fs = [function(F) || F <- Fs0],
- {ok,{Mod,Exp,Attr,Fs,Lc}}.
-
-function({function,Name,Arity,CLabel,Is0}) ->
- try
- Is = bs_opt(Is0),
- {function,Name,Arity,CLabel,Is}
- catch
- Class:Error:Stack ->
- io:fwrite("Function: ~w/~w\n", [Name,Arity]),
- erlang:raise(Class, Error, Stack)
- end.
-
-%%%
-%%% Evaluate construction of constant bit fields.
-%%% Combine bs_skip_bits2 and bs_test_tail2 instructions.
-%%%
-
-bs_opt([{bs_put,_,_,_}=I|Is0]) ->
- {BsPuts0,Is} = collect_bs_puts(Is0, [I]),
- BsPuts = opt_bs_puts(BsPuts0),
- BsPuts ++ bs_opt(Is);
-bs_opt([{test,bs_skip_bits2,F,[Ctx,{integer,I},Unit,_Flags]},
- {test,bs_test_tail2,F,[Ctx,Bits]}|Is]) ->
- [{test,bs_test_tail2,F,[Ctx,Bits+I*Unit]}|bs_opt(Is)];
-bs_opt([{test,bs_skip_bits2,F,[Ctx,{integer,I1},Unit1,Flags]},
- {test,bs_skip_bits2,F,[Ctx,{integer,I2},Unit2,_]}|Is]) ->
- I = {test,bs_skip_bits2,F,
- [Ctx,{integer,I1*Unit1+I2*Unit2},1,Flags]},
- bs_opt([I|Is]);
-bs_opt([I|Is]) ->
- [I|bs_opt(Is)];
-bs_opt([]) -> [].
-
-collect_bs_puts([{bs_put,_,_,_}=I|Is], Acc) ->
- collect_bs_puts(Is, [I|Acc]);
-collect_bs_puts([_|_]=Is, Acc) ->
- {reverse(Acc),Is}.
-
-opt_bs_puts(Is) ->
- opt_bs_1(Is, []).
-
-opt_bs_1([{bs_put,Fail,
- {bs_put_float,1,Flags0},[{integer,Sz},Src]}=I0|Is], Acc) ->
- try eval_put_float(Src, Sz, Flags0) of
- <<Int:Sz>> ->
- Flags = force_big(Flags0),
- I = {bs_put,Fail,{bs_put_integer,1,Flags},
- [{integer,Sz},{integer,Int}]},
- opt_bs_1([I|Is], Acc)
- catch
- error:_ ->
- opt_bs_1(Is, [I0|Acc])
- end;
-opt_bs_1([{bs_put,_,{bs_put_integer,1,_},[{integer,8},{integer,_}]}|_]=IsAll,
- Acc0) ->
- {Is,Acc} = bs_collect_string(IsAll, Acc0),
- opt_bs_1(Is, Acc);
-opt_bs_1([{bs_put,Fail,{bs_put_integer,1,F},[{integer,Sz},{integer,N}]}=I|Is0],
- Acc) when Sz > 8 ->
- case field_endian(F) of
- big ->
- %% We can do this optimization for any field size without
- %% risk for code explosion.
- case bs_split_int(N, Sz, Fail, Is0) of
- no_split -> opt_bs_1(Is0, [I|Acc]);
- Is -> opt_bs_1(Is, Acc)
- end;
- little when Sz < 128 ->
- %% We only try to optimize relatively small fields, to
- %% avoid an explosion in code size.
- <<Int:Sz>> = <<N:Sz/little>>,
- Flags = force_big(F),
- Is = [{bs_put,Fail,{bs_put_integer,1,Flags},
- [{integer,Sz},{integer,Int}]}|Is0],
- opt_bs_1(Is, Acc);
- _ -> %native or too wide little field
- opt_bs_1(Is0, [I|Acc])
- end;
-opt_bs_1([{bs_put,Fail,{Op,U,F},[{integer,Sz},Src]}|Is], Acc) when U > 1 ->
- opt_bs_1([{bs_put,Fail,{Op,1,F},[{integer,U*Sz},Src]}|Is], Acc);
-opt_bs_1([I|Is], Acc) ->
- opt_bs_1(Is, [I|Acc]);
-opt_bs_1([], Acc) -> reverse(Acc).
-
-eval_put_float(Src, Sz, Flags) when Sz =< 256 ->
- %%Only evaluate if Sz is reasonable.
- Val = value(Src),
- case field_endian(Flags) of
- little -> <<Val:Sz/little-float-unit:1>>;
- big -> <<Val:Sz/big-float-unit:1>>
- %% native intentionally not handled here - we can't optimize
- %% it.
- end.
-
-value({integer,I}) -> I;
-value({float,F}) -> F.
-
-bs_collect_string(Is, [{bs_put,_,{bs_put_string,Len,{string,Str}},[]}|Acc]) ->
- bs_coll_str_1(Is, Len, reverse(Str), Acc);
-bs_collect_string(Is, Acc) ->
- bs_coll_str_1(Is, 0, [], Acc).
-
-bs_coll_str_1([{bs_put,_,{bs_put_integer,U,_},[{integer,Sz},{integer,V}]}|Is],
- Len, StrAcc, IsAcc) when U*Sz =:= 8 ->
- Byte = V band 16#FF,
- bs_coll_str_1(Is, Len+1, [Byte|StrAcc], IsAcc);
-bs_coll_str_1(Is, Len, StrAcc, IsAcc) ->
- {Is,[{bs_put,{f,0},{bs_put_string,Len,{string,reverse(StrAcc)}},[]}|IsAcc]}.
-
-field_endian({field_flags,F}) -> field_endian_1(F).
-
-field_endian_1([big=E|_]) -> E;
-field_endian_1([little=E|_]) -> E;
-field_endian_1([native=E|_]) -> E;
-field_endian_1([_|Fs]) -> field_endian_1(Fs).
-
-force_big({field_flags,F}) ->
- {field_flags,force_big_1(F)}.
-
-force_big_1([big|_]=Fs) -> Fs;
-force_big_1([little|Fs]) -> [big|Fs];
-force_big_1([F|Fs]) -> [F|force_big_1(Fs)].
-
-bs_split_int(0, Sz, _, _) when Sz > 64 ->
- %% We don't want to split in this case because the
- %% string will consist of only zeroes.
- no_split;
-bs_split_int(-1, Sz, _, _) when Sz > 64 ->
- %% We don't want to split in this case because the
- %% string will consist of only 255 bytes.
- no_split;
-bs_split_int(N, Sz, Fail, Acc) ->
- FirstByteSz = case Sz rem 8 of
- 0 -> 8;
- Rem -> Rem
- end,
- bs_split_int_1(N, FirstByteSz, Sz, Fail, Acc).
-
-bs_split_int_1(-1, _, Sz, Fail, Acc) when Sz > 64 ->
- I = {bs_put,Fail,{bs_put_integer,1,{field_flags,[big]}},
- [{integer,Sz},{integer,-1}]},
- [I|Acc];
-bs_split_int_1(0, _, Sz, Fail, Acc) when Sz > 64 ->
- I = {bs_put,Fail,{bs_put_integer,1,{field_flags,[big]}},
- [{integer,Sz},{integer,0}]},
- [I|Acc];
-bs_split_int_1(N, ByteSz, Sz, Fail, Acc) when Sz > 0 ->
- Mask = (1 bsl ByteSz) - 1,
- I = {bs_put,Fail,{bs_put_integer,1,{field_flags,[big]}},
- [{integer,ByteSz},{integer,N band Mask}]},
- bs_split_int_1(N bsr ByteSz, 8, Sz-ByteSz, Fail, [I|Acc]);
-bs_split_int_1(_, _, _, _, Acc) -> Acc.