diff options
Diffstat (limited to 'lib/compiler/src/beam_utils.erl')
| -rw-r--r-- | lib/compiler/src/beam_utils.erl | 514 |
1 files changed, 243 insertions, 271 deletions
diff --git a/lib/compiler/src/beam_utils.erl b/lib/compiler/src/beam_utils.erl index 194f089ba1..249d9395ca 100644 --- a/lib/compiler/src/beam_utils.erl +++ b/lib/compiler/src/beam_utils.erl @@ -1,18 +1,19 @@ %% %% %CopyrightBegin% %% -%% Copyright Ericsson AB 2007-2012. All Rights Reserved. +%% Copyright Ericsson AB 2007-2016. All Rights Reserved. %% -%% The contents of this file are subject to the Erlang Public License, -%% Version 1.1, (the "License"); you may not use this file except in -%% compliance with the License. You should have received a copy of the -%% Erlang Public License along with this software. If not, it can be -%% retrieved online at http://www.erlang.org/. +%% 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 %% -%% Software distributed under the License is distributed on an "AS IS" -%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See -%% the License for the specific language governing rights and limitations -%% under the License. +%% 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% %% @@ -24,7 +25,8 @@ is_not_used/3,is_not_used_at/3, empty_label_index/0,index_label/3,index_labels/1, code_at/2,bif_to_test/3,is_pure_test/1, - live_opt/1,delete_live_annos/1,combine_heap_needs/2]). + live_opt/1,delete_live_annos/1,combine_heap_needs/2, + split_even/1]). -import(lists, [member/2,sort/1,reverse/1,splitwith/2]). @@ -61,22 +63,20 @@ is_killed_block(R, Is) -> %% to determine the kill state across branches. is_killed(R, Is, D) -> - St = #live{bl=fun check_killed_block/2,lbl=D,res=gb_trees:empty()}, + St = #live{bl=check_killed_block_fun(),lbl=D,res=gb_trees:empty()}, case check_liveness(R, Is, St) of {killed,_} -> true; - {used,_} -> false; - {unknown,_} -> false + {used,_} -> false end. %% is_killed_at(Reg, Lbl, State) -> true|false %% Determine whether Reg is killed at label Lbl. is_killed_at(R, Lbl, D) when is_integer(Lbl) -> - St0 = #live{bl=fun check_killed_block/2,lbl=D,res=gb_trees:empty()}, + St0 = #live{bl=check_killed_block_fun(),lbl=D,res=gb_trees:empty()}, case check_liveness_at(R, Lbl, St0) of {killed,_} -> true; - {used,_} -> false; - {unknown,_} -> false + {used,_} -> false end. %% is_not_used(Register, [Instruction], State) -> true|false @@ -87,11 +87,10 @@ is_killed_at(R, Lbl, D) when is_integer(Lbl) -> %% across branches. is_not_used(R, Is, D) -> - St = #live{bl=fun check_used_block/2,lbl=D,res=gb_trees:empty()}, + St = #live{bl=fun check_used_block/3,lbl=D,res=gb_trees:empty()}, case check_liveness(R, Is, St) of {killed,_} -> true; - {used,_} -> false; - {unknown,_} -> false + {used,_} -> false end. %% is_not_used(Register, [Instruction], State) -> true|false @@ -102,11 +101,10 @@ is_not_used(R, Is, D) -> %% across branches. is_not_used_at(R, Lbl, D) -> - St = #live{bl=fun check_used_block/2,lbl=D,res=gb_trees:empty()}, + St = #live{bl=fun check_used_block/3,lbl=D,res=gb_trees:empty()}, case check_liveness_at(R, Lbl, St) of {killed,_} -> true; - {used,_} -> false; - {unknown,_} -> false + {used,_} -> false end. %% index_labels(FunctionIs) -> State @@ -126,8 +124,7 @@ empty_label_index() -> %% Add an index for a label. index_label(Lbl, Is0, Acc) -> - Is = lists:dropwhile(fun({label,_}) -> true; - (_) -> false end, Is0), + Is = drop_labels(Is0), gb_trees:enter(Lbl, Is, Acc). @@ -135,10 +132,7 @@ index_label(Lbl, Is0, Acc) -> %% Retrieve the code at the given label. code_at(L, Ll) -> - case gb_trees:lookup(L, Ll) of - {value,Code} -> Code; - none -> none - end. + gb_trees:get(L, Ll). %% bif_to_test(Bif, [Op], Fail) -> {test,Test,Fail,[Op]} %% Convert a BIF to a test. Fail if not possible. @@ -152,6 +146,7 @@ bif_to_test(is_function, [_]=Ops, Fail) -> {test,is_function,Fail,Ops}; bif_to_test(is_function, [_,_]=Ops, Fail) -> {test,is_function2,Fail,Ops}; bif_to_test(is_integer, [_]=Ops, Fail) -> {test,is_integer,Fail,Ops}; bif_to_test(is_list, [_]=Ops, Fail) -> {test,is_list,Fail,Ops}; +bif_to_test(is_map, [_]=Ops, Fail) -> {test,is_map,Fail,Ops}; bif_to_test(is_number, [_]=Ops, Fail) -> {test,is_number,Fail,Ops}; bif_to_test(is_pid, [_]=Ops, Fail) -> {test,is_pid,Fail,Ops}; bif_to_test(is_port, [_]=Ops, Fail) -> {test,is_port,Fail,Ops}; @@ -161,10 +156,10 @@ bif_to_test('=<', [A,B], Fail) -> {test,is_ge,Fail,[B,A]}; bif_to_test('>', [A,B], Fail) -> {test,is_lt,Fail,[B,A]}; bif_to_test('<', [_,_]=Ops, Fail) -> {test,is_lt,Fail,Ops}; bif_to_test('>=', [_,_]=Ops, Fail) -> {test,is_ge,Fail,Ops}; -bif_to_test('==', [A,[]], Fail) -> {test,is_nil,Fail,[A]}; +bif_to_test('==', [A,nil], Fail) -> {test,is_nil,Fail,[A]}; bif_to_test('==', [_,_]=Ops, Fail) -> {test,is_eq,Fail,Ops}; bif_to_test('/=', [_,_]=Ops, Fail) -> {test,is_ne,Fail,Ops}; -bif_to_test('=:=', [A,[]], Fail) -> {test,is_nil,Fail,[A]}; +bif_to_test('=:=', [A,nil], Fail) -> {test,is_nil,Fail,[A]}; bif_to_test('=:=', [_,_]=Ops, Fail) -> {test,is_eq_exact,Fail,Ops}; bif_to_test('=/=', [_,_]=Ops, Fail) -> {test,is_ne_exact,Fail,Ops}; bif_to_test(is_record, [_,_,_]=Ops, Fail) -> {test,is_record,Fail,Ops}. @@ -172,8 +167,7 @@ bif_to_test(is_record, [_,_,_]=Ops, Fail) -> {test,is_record,Fail,Ops}. %% is_pure_test({test,Op,Fail,Ops}) -> true|false. %% Return 'true' if the test instruction does not modify any -%% registers and/or bit syntax matching state, nor modifies -%% any bit syntax matching state. +%% registers and/or bit syntax matching state. %% is_pure_test({test,is_eq,_,[_,_]}) -> true; is_pure_test({test,is_ne,_,[_,_]}) -> true; @@ -184,6 +178,9 @@ is_pure_test({test,is_lt,_,[_,_]}) -> true; is_pure_test({test,is_nil,_,[_]}) -> true; is_pure_test({test,is_nonempty_list,_,[_]}) -> true; is_pure_test({test,test_arity,_,[_,_]}) -> true; +is_pure_test({test,has_map_fields,_,[_|_]}) -> true; +is_pure_test({test,is_bitstr,_,[_]}) -> true; +is_pure_test({test,is_function2,_,[_,_]}) -> true; is_pure_test({test,Op,_,Ops}) -> erl_internal:new_type_test(Op, length(Ops)). @@ -192,7 +189,7 @@ is_pure_test({test,Op,_,Ops}) -> %% Go through the instruction sequence in reverse execution %% order, keep track of liveness and remove 'move' instructions %% whose destination is a register that will not be used. -%% Also insert {'%live',Live} annotations at the beginning +%% Also insert {'%live',Live,Regs} annotations at the beginning %% and end of each block. %% live_opt(Is0) -> @@ -213,7 +210,7 @@ delete_live_annos([{block,Bl0}|Is]) -> [] -> delete_live_annos(Is); [_|_]=Bl -> [{block,Bl}|delete_live_annos(Is)] end; -delete_live_annos([{'%live',_}|Is]) -> +delete_live_annos([{'%live',_,_}|Is]) -> delete_live_annos(Is); delete_live_annos([I|Is]) -> [I|delete_live_annos(Is)]; @@ -231,25 +228,27 @@ combine_heap_needs(Words, {alloc,Alloc}) when is_integer(Words) -> combine_heap_needs(H1, H2) when is_integer(H1), is_integer(H2) -> H1+H2. +%% split_even/1 +%% [1,2,3,4,5,6] -> {[1,3,5],[2,4,6]} + +split_even(Rs) -> split_even(Rs, [], []). + + %%% %%% Local functions. %%% -%% check_liveness(Reg, [Instruction], {State,BlockCheckFun}) -> -%% {killed | used | unknown,UpdateState} -%% Finds out how Reg is used in the instruction sequence. Returns one of: -%% killed - Reg is assigned a new value or killed by an allocation instruction -%% used - Reg is used (or possibly referenced by an allocation instruction) -%% unknown - not possible to determine (perhaps because of an instruction -%% that we don't recognize) +%% check_liveness(Reg, [Instruction], #live{}) -> +%% {killed | used, #live{}} +%% Find out whether Reg is used or killed in instruction sequence. +%% 'killed' means that Reg is assigned a new value or killed by an +%% allocation instruction. 'used' means that Reg is used in some way. -check_liveness(R, [{set,_,_,_}=I|_], St) -> - erlang:error(only_allowed_in_blocks, [R,I,St]); -check_liveness(R, [{block,Blk}|Is], #live{bl=BlockCheck}=St) -> - case BlockCheck(R, Blk) of - transparent -> check_liveness(R, Is, St); - Other when is_atom(Other) -> {Other,St} +check_liveness(R, [{block,Blk}|Is], #live{bl=BlockCheck}=St0) -> + case BlockCheck(R, Blk, St0) of + {transparent,St} -> check_liveness(R, Is, St); + {Other,_}=Res when is_atom(Other) -> Res end; check_liveness(R, [{label,_}|Is], St) -> check_liveness(R, Is, St); @@ -263,26 +262,14 @@ check_liveness(R, [{test,_,{f,Fail},As}|Is], St0) -> {_,_}=Other -> Other end end; -check_liveness(R, [{test,_,{f,Fail},Live,Ss,_}|Is], St0) -> - case R of - {x,X} -> - case X < Live orelse member(R, Ss) of - true -> {used,St0}; - false -> check_liveness_at(R, Fail, St0) - end; - {y,_} -> - case check_liveness_at(R, Fail, St0) of - {killed,St} -> check_liveness(R, Is, St); - {_,_}=Other -> Other - end - end; -check_liveness(R, [{select_val,R,_,_}|_], St) -> - {used,St}; -check_liveness(R, [{select_val,_,Fail,{list,Branches}}|_], St) -> - check_liveness_everywhere(R, [Fail|Branches], St); -check_liveness(R, [{select_tuple_arity,R,_,_}|_], St) -> +check_liveness(R, [{test,Op,Fail,Live,Ss,Dst}|Is], St) -> + %% Check this instruction as a block to get a less conservative + %% result if the caller is is_not_used/3. + Block = [{set,[Dst],Ss,{alloc,Live,{bif,Op,Fail}}}], + check_liveness(R, [{block,Block}|Is], St); +check_liveness(R, [{select,_,R,_,_}|_], St) -> {used,St}; -check_liveness(R, [{select_tuple_arity,_,Fail,{list,Branches}}|_], St) -> +check_liveness(R, [{select,_,_,Fail,Branches}|_], St) -> check_liveness_everywhere(R, [Fail|Branches], St); check_liveness(R, [{jump,{f,F}}|_], St) -> check_liveness_at(R, F, St); @@ -301,78 +288,64 @@ check_liveness(R, [{kill,R}|_], St) -> {killed,St}; check_liveness(R, [{kill,_}|Is], St) -> check_liveness(R, Is, St); -check_liveness(R, [bs_init_writable|Is], St) -> - if - R =:= {x,0} -> {used,St}; - true -> check_liveness(R, Is, St) - end; -check_liveness(R, [{bs_private_append,_,Bits,_,Bin,_,Dst}|Is], St) -> - case R of - Bits -> {used,St}; - Bin -> {used,St}; - Dst -> {killed,St}; - _ -> check_liveness(R, Is, St) +check_liveness(R, [{bs_init,_,_,none,Ss,Dst}|Is], St) -> + case member(R, Ss) of + true -> + {used,St}; + false -> + if + R =:= Dst -> {killed,St}; + true -> check_liveness(R, Is, St) + end end; -check_liveness(R, [{bs_append,_,Bits,_,_,_,Bin,_,Dst}|Is], St) -> +check_liveness(R, [{bs_init,_,_,Live,Ss,Dst}|Is], St) -> case R of - Bits -> {used,St}; - Bin -> {used,St}; - Dst -> {killed,St}; - _ -> check_liveness(R, Is, St) - end; -check_liveness(R, [{bs_init2,_,_,_,_,_,Dst}|Is], St) -> - if - R =:= Dst -> {killed,St}; - true -> check_liveness(R, Is, St) - end; -check_liveness(R, [{bs_init_bits,_,_,_,_,_,Dst}|Is], St) -> - if - R =:= Dst -> {killed,St}; - true -> check_liveness(R, Is, St) + {x,X} -> + case X < Live orelse member(R, Ss) of + true -> {used,St}; + false -> {killed,St} + end; + {y,_} -> + case member(R, Ss) of + true -> {used,St}; + false -> + if + R =:= Dst -> {killed,St}; + true -> check_liveness(R, Is, St) + end + end end; -check_liveness(R, [{bs_put_string,_,_}|Is], St) -> - check_liveness(R, Is, St); check_liveness(R, [{deallocate,_}|Is], St) -> case R of {y,_} -> {killed,St}; _ -> check_liveness(R, Is, St) end; -check_liveness(R, [return|_], St) -> - check_liveness_live_ret(R, 1, St); -check_liveness(R, [{call_last,Live,_,_}|_], St) -> - check_liveness_live_ret(R, Live, St); -check_liveness(R, [{call_only,Live,_}|_], St) -> - check_liveness_live_ret(R, Live, St); -check_liveness(R, [{call_ext_last,Live,_,_}|_], St) -> - check_liveness_live_ret(R, Live, St); -check_liveness(R, [{call_ext_only,Live,_}|_], St) -> - check_liveness_live_ret(R, Live, St); +check_liveness({x,_}=R, [return|_], St) -> + case R of + {x,0} -> {used,St}; + {x,_} -> {killed,St} + end; check_liveness(R, [{call,Live,_}|Is], St) -> case R of {x,X} when X < Live -> {used,St}; {x,_} -> {killed,St}; {y,_} -> check_liveness(R, Is, St) end; -check_liveness(R, [{call_ext,Live,Func}|Is], St) -> +check_liveness(R, [{call_ext,Live,_}=I|Is], St) -> case R of {x,X} when X < Live -> {used,St}; {x,_} -> {killed,St}; {y,_} -> - {extfunc,Mod,Name,Arity} = Func, - case erl_bifs:is_exit_bif(Mod, Name, Arity) of + case beam_jump:is_exit_instruction(I) of false -> check_liveness(R, Is, St); true -> - %% We must make sure we don't check beyond this instruction - %% or we will fall through into random unrelated code and - %% get stuck in a loop. - %% - %% We don't want to overwrite a 'catch', so consider this - %% register in use. - %% - {used,St} + %% We must make sure we don't check beyond this + %% instruction or we will fall through into random + %% unrelated code and get stuck in a loop. + {killed,St} end end; check_liveness(R, [{call_fun,Live}|Is], St) -> @@ -387,19 +360,6 @@ check_liveness(R, [{apply,Args}|Is], St) -> {x,_} -> {killed,St}; {y,_} -> check_liveness(R, Is, St) end; -check_liveness(R, [{apply_last,Args,_}|_], St) -> - check_liveness_live_ret(R, Args+2, St); -check_liveness(R, [send|Is], St) -> - case R of - {x,X} when X < 2 -> {used,St}; - {x,_} -> {killed,St}; - {y,_} -> check_liveness(R, Is, St) - end; -check_liveness({x,R}, [{'%live',Live}|Is], St) -> - if - R < Live -> check_liveness(R, Is, St); - true -> {killed,St} - end; check_liveness(R, [{bif,Op,{f,Fail},Ss,D}|Is], St0) -> case check_liveness_fail(R, Op, Ss, Fail, St0) of {killed,St} = Killed -> @@ -429,25 +389,9 @@ check_liveness(R, [{gc_bif,Op,{f,Fail},Live,Ss,D}|Is], St0) -> Other end end; -check_liveness(R, [{bs_add,{f,0},Ss,D}|Is], St) -> +check_liveness(R, [{bs_put,{f,0},_,Ss}|Is], St) -> case member(R, Ss) of true -> {used,St}; - false when R =:= D -> {killed,St}; - false -> check_liveness(R, Is, St) - end; -check_liveness(R, [{bs_put_binary,{f,0},Sz,_,_,Src}|Is], St) -> - case member(R, [Sz,Src]) of - true -> {used,St}; - false -> check_liveness(R, Is, St) - end; -check_liveness(R, [{bs_put_integer,{f,0},Sz,_,_,Src}|Is], St) -> - case member(R, [Sz,Src]) of - true -> {used,St}; - false -> check_liveness(R, Is, St) - end; -check_liveness(R, [{bs_put_float,{f,0},Sz,_,_,Src}|Is], St) -> - case member(R, [Sz,Src]) of - true -> {used,St}; false -> check_liveness(R, Is, St) end; check_liveness(R, [{bs_restore2,S,_}|Is], St) -> @@ -472,6 +416,16 @@ check_liveness(R, [{make_fun2,_,_,_,NumFree}|Is], St) -> {x,_} -> {killed,St}; _ -> check_liveness(R, Is, St) end; +check_liveness({x,_}=R, [{'catch',_,_}|Is], St) -> + %% All x registers will be killed if an exception occurs. + %% Therefore we only need to check the liveness for the + %% instructions following the catch instruction. + check_liveness(R, Is, St); +check_liveness({x,_}=R, [{'try',_,_}|Is], St) -> + %% All x registers will be killed if an exception occurs. + %% Therefore we only need to check the liveness for the + %% instructions inside the 'try' block. + check_liveness(R, Is, St); check_liveness(R, [{try_end,Y}|Is], St) -> case R of Y -> @@ -505,20 +459,54 @@ check_liveness(R, [{loop_rec,{f,_},{x,0}}|_], St) -> {x,_} -> {killed,St}; _ -> - %% y register. Rarely happens. Be very conversative. - {unknown,St} + %% y register. Rarely happens. Be very conversative and + %% assume it's used. + {used,St} end; check_liveness(R, [{loop_rec_end,{f,Fail}}|_], St) -> check_liveness_at(R, Fail, St); check_liveness(R, [{line,_}|Is], St) -> check_liveness(R, Is, St); +check_liveness(R, [{get_map_elements,{f,Fail},S,{list,L}}|Is], St0) -> + {Ss,Ds} = split_even(L), + case member(R, [S|Ss]) of + true -> + {used,St0}; + false -> + case check_liveness_at(R, Fail, St0) of + {killed,St}=Killed -> + case member(R, Ds) of + true -> Killed; + false -> check_liveness(R, Is, St) + end; + Other -> + Other + end + end; +check_liveness(R, [{put_map,{f,_},_,Src,_D,Live,{list,_}}|_], St0) -> + case R of + Src -> + {used,St0}; + {x,X} when X < Live -> + {used,St0}; + {x,_} -> + {killed,St0}; + {y,_} -> + %% Conservatively mark it as used. + {used,St0} + end; +check_liveness(R, [{test_heap,N,Live}|Is], St) -> + I = {block,[{set,[],[],{alloc,Live,{nozero,nostack,N,[]}}}]}, + check_liveness(R, [I|Is], St); +check_liveness(R, [{allocate_zero,N,Live}|Is], St) -> + I = {block,[{set,[],[],{alloc,Live,{zero,N,0,[]}}}]}, + check_liveness(R, [I|Is], St); +check_liveness(R, [{get_list,S,D1,D2}|Is], St) -> + I = {block,[{set,[D1,D2],[S],get_list}]}, + check_liveness(R, [I|Is], St); check_liveness(_R, Is, St) when is_list(Is) -> -%% case Is of -%% [I|_] -> -%% io:format("~p ~p\n", [_R,I]); -%% _ -> ok -%% end, - {unknown,St}. + %% Not implemented. Conservatively assume that the register is used. + {used,St}. check_liveness_everywhere(R, [{f,Lbl}|T], St0) -> case check_liveness_at(R, Lbl, St0) of @@ -537,7 +525,7 @@ check_liveness_at(R, Lbl, #live{lbl=Ll,res=ResMemorized}=St0) -> none -> {Res,St} = case gb_trees:lookup(Lbl, Ll) of {value,Is} -> check_liveness(R, Is, St0); - none -> {unknown,St0} + none -> {used,St0} end, {Res,St#live{res=gb_trees:insert(Lbl, Res, St#live.res)}} end. @@ -545,14 +533,6 @@ check_liveness_at(R, Lbl, #live{lbl=Ll,res=ResMemorized}=St0) -> check_liveness_ret(R, R, St) -> {used,St}; check_liveness_ret(_, _, St) -> {killed,St}. -check_liveness_live_ret({x,R}, Live, St) -> - if - R < Live -> {used,St}; - true -> {killed,St} - end; -check_liveness_live_ret({y,_}, _, St) -> - {killed,St}. - check_liveness_fail(_, _, _, 0, St) -> {killed,St}; check_liveness_fail(R, Op, Args, Fail, St) -> @@ -572,6 +552,9 @@ check_liveness_fail(R, Op, Args, Fail, St) -> %% %% (Unknown instructions will cause an exception.) +check_killed_block_fun() -> + fun(R, Is, St) -> {check_killed_block(R, Is),St} end. + check_killed_block({x,X}, [{set,_,_,{alloc,Live,_}}|_]) -> if X >= Live -> killed; @@ -586,9 +569,9 @@ check_killed_block(R, [{set,Ds,Ss,_Op}|Is]) -> false -> check_killed_block(R, Is) end end; -check_killed_block(R, [{'%live',Live}|Is]) -> +check_killed_block(R, [{'%live',_,Regs}|Is]) -> case R of - {x,X} when X >= Live -> killed; + {x,X} when (Regs bsr X) band 1 =:= 0 -> killed; _ -> check_killed_block(R, Is) end; check_killed_block(_, []) -> transparent. @@ -599,38 +582,61 @@ check_killed_block(_, []) -> transparent. %% killed - Reg is assigned a new value or killed by an allocation instruction %% transparent - Reg is neither used nor killed %% used - Reg is explicitly used by an instruction -%% -%% (Unknown instructions will cause an exception.) +%% +%% '%live' annotations are not allowed. +%% +%% (Unknown instructions will cause an exception.) -check_used_block({x,X}=R, [{set,_,_,{alloc,Live,_}}|Is]) -> +check_used_block({x,X}=R, [{set,Ds,Ss,{alloc,Live,Op}}|Is], St) -> if - X >= Live -> killed; - true -> check_used_block(R, Is) + X >= Live -> {killed,St}; + true -> check_used_block_1(R, Ss, Ds, Op, Is, St) end; -check_used_block(R, [{set,Ds,Ss,_Op}|Is]) -> +check_used_block(R, [{set,Ds,Ss,Op}|Is], St) -> + check_used_block_1(R, Ss, Ds, Op, Is, St); +check_used_block(_, [], St) -> {transparent,St}. + +check_used_block_1(R, Ss, Ds, Op, Is, St0) -> case member(R, Ss) of - true -> used; + true -> + {used,St0}; false -> - case member(R, Ds) of - true -> killed; - false -> check_used_block(R, Is) + case is_reg_used_at(R, Op, St0) of + {true,St} -> + {used,St}; + {false,St} -> + case member(R, Ds) of + true -> {killed,St}; + false -> check_used_block(R, Is, St) + end end - end; -check_used_block(R, [{'%live',Live}|Is]) -> - case R of - {x,X} when X >= Live -> killed; - _ -> check_used_block(R, Is) - end; -check_used_block(_, []) -> transparent. + end. + +is_reg_used_at(R, {gc_bif,_,{f,Lbl}}, St) -> + is_reg_used_at_1(R, Lbl, St); +is_reg_used_at(R, {bif,_,{f,Lbl}}, St) -> + is_reg_used_at_1(R, Lbl, St); +is_reg_used_at(_, _, St) -> + {false,St}. + +is_reg_used_at_1(_, 0, St) -> + {false,St}; +is_reg_used_at_1(R, Lbl, St0) -> + case check_liveness_at(R, Lbl, St0) of + {killed,St} -> {false,St}; + {used,St} -> {true,St} + end. index_labels_1([{label,Lbl}|Is0], Acc) -> - Is = lists:dropwhile(fun({label,_}) -> true; - (_) -> false end, Is0), + Is = drop_labels(Is0), index_labels_1(Is0, [{Lbl,Is}|Acc]); index_labels_1([_|Is], Acc) -> index_labels_1(Is, Acc); index_labels_1([], Acc) -> gb_trees:from_orddict(sort(Acc)). +drop_labels([{label,_}|Is]) -> drop_labels(Is); +drop_labels(Is) -> Is. + %% Help functions for combine_heap_needs. combine_alloc_lists(Al1, Al2) -> @@ -654,49 +660,21 @@ combine_alloc_lists_1([]) -> []. live_opt([{bs_context_to_binary,Src}=I|Is], Regs0, D, Acc) -> Regs = x_live([Src], Regs0), live_opt(Is, Regs, D, [I|Acc]); -live_opt([{bs_add,Fail,[Src1,Src2,_],Dst}=I|Is], Regs0, D, Acc) -> - Regs1 = x_live([Src1,Src2], x_dead([Dst], Regs0)), - Regs = live_join_label(Fail, D, Regs1), - live_opt(Is, Regs, D, [I|Acc]); -live_opt([{bs_init2,Fail,_,_,Live,_,_}=I|Is], _, D, Acc) -> - Regs1 = live_call(Live), - Regs = live_join_label(Fail, D, Regs1), - live_opt(Is, Regs, D, [I|Acc]); -live_opt([{bs_init_bits,Fail,Src1,_,Live,_,Src2}=I|Is], _, D, Acc) -> - Regs1 = live_call(Live), - Regs2 = x_live([Src1,Src2], Regs1), - Regs = live_join_label(Fail, D, Regs2), - live_opt(Is, Regs, D, [I|Acc]); -live_opt([{bs_append,Fail,Src1,_,Live,_,Src2,_,Dst}=I|Is], _Regs0, D, Acc) -> - Regs1 = x_dead([Dst], x_live([Src1,Src2], live_call(Live))), - Regs = live_join_label(Fail, D, Regs1), - live_opt(Is, Regs, D, [I|Acc]); -live_opt([{bs_private_append,Fail,Src1,_,Src2,_,Dst}=I|Is], Regs0, D, Acc) -> - Regs1 = x_live([Src1,Src2], x_dead([Dst], Regs0)), +live_opt([{bs_init,Fail,_,none,Ss,Dst}=I|Is], Regs0, D, Acc) -> + Regs1 = x_live(Ss, x_dead([Dst], Regs0)), Regs = live_join_label(Fail, D, Regs1), live_opt(Is, Regs, D, [I|Acc]); -live_opt([{bs_put_binary,Fail,Src1,_,_,Src2}=I|Is], Regs0, D, Acc) -> - Regs1 = x_live([Src1,Src2], Regs0), - Regs = live_join_label(Fail, D, Regs1), - live_opt(Is, Regs, D, [I|Acc]); -live_opt([{bs_put_float,Fail,Src1,_,_,Src2}=I|Is], Regs0, D, Acc) -> - Regs1 = x_live([Src1,Src2], Regs0), - Regs = live_join_label(Fail, D, Regs1), - live_opt(Is, Regs, D, [I|Acc]); -live_opt([{bs_put_integer,Fail,Src1,_,_,Src2}=I|Is], Regs0, D, Acc) -> - Regs1 = x_live([Src1,Src2], Regs0), - Regs = live_join_label(Fail, D, Regs1), - live_opt(Is, Regs, D, [I|Acc]); -live_opt([{bs_put_utf8,Fail,_,Src}=I|Is], Regs0, D, Acc) -> - Regs1 = x_live([Src], Regs0), - Regs = live_join_label(Fail, D, Regs1), - live_opt(Is, Regs, D, [I|Acc]); -live_opt([{bs_put_utf16,Fail,_,Src}=I|Is], Regs0, D, Acc) -> - Regs1 = x_live([Src], Regs0), - Regs = live_join_label(Fail, D, Regs1), +live_opt([{bs_init,Fail,Info,Live0,Ss,Dst}|Is], Regs0, D, Acc) -> + Regs1 = x_dead([Dst], Regs0), + Live = live_regs(Regs1), + true = Live =< Live0, %Assertion. + Regs2 = live_call(Live), + Regs3 = x_live(Ss, Regs2), + Regs = live_join_label(Fail, D, Regs3), + I = {bs_init,Fail,Info,Live,Ss,Dst}, live_opt(Is, Regs, D, [I|Acc]); -live_opt([{bs_put_utf32,Fail,_,Src}=I|Is], Regs0, D, Acc) -> - Regs1 = x_live([Src], Regs0), +live_opt([{bs_put,Fail,_,Ss}=I|Is], Regs0, D, Acc) -> + Regs1 = x_live(Ss, Regs0), Regs = live_join_label(Fail, D, Regs1), live_opt(Is, Regs, D, [I|Acc]); live_opt([{bs_restore2,Src,_}=I|Is], Regs0, D, Acc) -> @@ -705,14 +683,6 @@ live_opt([{bs_restore2,Src,_}=I|Is], Regs0, D, Acc) -> live_opt([{bs_save2,Src,_}=I|Is], Regs0, D, Acc) -> Regs = x_live([Src], Regs0), live_opt(Is, Regs, D, [I|Acc]); -live_opt([{bs_utf8_size,Fail,Src,Dst}=I|Is], Regs0, D, Acc) -> - Regs1 = x_live([Src], x_dead([Dst], Regs0)), - Regs = live_join_label(Fail, D, Regs1), - live_opt(Is, Regs, D, [I|Acc]); -live_opt([{bs_utf16_size,Fail,Src,Dst}=I|Is], Regs0, D, Acc) -> - Regs1 = x_live([Src], x_dead([Dst], Regs0)), - Regs = live_join_label(Fail, D, Regs1), - live_opt(Is, Regs, D, [I|Acc]); live_opt([{test,bs_start_match2,Fail,Live,[Src,_],_}=I|Is], _, D, Acc) -> Regs0 = live_call(Live), Regs1 = x_live([Src], Regs0), @@ -721,9 +691,9 @@ live_opt([{test,bs_start_match2,Fail,Live,[Src,_],_}=I|Is], _, D, Acc) -> %% Other instructions. live_opt([{block,Bl0}|Is], Regs0, D, Acc) -> - Live0 = {'%live',live_regs(Regs0)}, + Live0 = {'%live',live_regs(Regs0),Regs0}, {Bl,Regs} = live_opt_block(reverse(Bl0), Regs0, D, [Live0]), - Live = {'%live',live_regs(Regs)}, + Live = {'%live',live_regs(Regs),Regs}, live_opt(Is, Regs, D, [{block,[Live|Bl]}|Acc]); live_opt([{label,L}=I|Is], Regs, D0, Acc) -> D = gb_trees:insert(L, Regs, D0), @@ -747,30 +717,16 @@ live_opt([{try_case_end,Src}=I|Is], _, D, Acc) -> live_opt([if_end=I|Is], _, D, Acc) -> Regs = 0, live_opt(Is, Regs, D, [I|Acc]); -live_opt([bs_init_writable=I|Is], _, D, Acc) -> - live_opt(Is, live_call(1), D, [I|Acc]); live_opt([{call,Arity,_}=I|Is], _, D, Acc) -> live_opt(Is, live_call(Arity), D, [I|Acc]); live_opt([{call_ext,Arity,_}=I|Is], _, D, Acc) -> live_opt(Is, live_call(Arity), D, [I|Acc]); live_opt([{call_fun,Arity}=I|Is], _, D, Acc) -> live_opt(Is, live_call(Arity+1), D, [I|Acc]); -live_opt([{call_last,Arity,_,_}=I|Is], _, D, Acc) -> - live_opt(Is, live_call(Arity), D, [I|Acc]); -live_opt([{call_ext_last,Arity,_,_}=I|Is], _, D, Acc) -> - live_opt(Is, live_call(Arity), D, [I|Acc]); live_opt([{apply,Arity}=I|Is], _, D, Acc) -> live_opt(Is, live_call(Arity+2), D, [I|Acc]); -live_opt([{apply_last,Arity,_}=I|Is], _, D, Acc) -> - live_opt(Is, live_call(Arity+2), D, [I|Acc]); -live_opt([{call_only,Arity,_}=I|Is], _, D, Acc) -> - live_opt(Is, live_call(Arity), D, [I|Acc]); -live_opt([{call_ext_only,Arity,_}=I|Is], _, D, Acc) -> - live_opt(Is, live_call(Arity), D, [I|Acc]); live_opt([{make_fun2,_,_,_,Arity}=I|Is], _, D, Acc) -> live_opt(Is, live_call(Arity), D, [I|Acc]); -live_opt([send=I|Is], _, D, Acc) -> - live_opt(Is, live_call(2), D, [I|Acc]); live_opt([{test,_,Fail,Ss}=I|Is], Regs0, D, Acc) -> Regs1 = x_live(Ss, Regs0), Regs = live_join_label(Fail, D, Regs1), @@ -780,27 +736,25 @@ live_opt([{test,_,Fail,Live,Ss,_}=I|Is], _, D, Acc) -> Regs1 = x_live(Ss, Regs0), Regs = live_join_label(Fail, D, Regs1), live_opt(Is, Regs, D, [I|Acc]); -live_opt([{select_val,Src,Fail,{list,List}}=I|Is], Regs0, D, Acc) -> +live_opt([{select,_,Src,Fail,List}=I|Is], Regs0, D, Acc) -> Regs1 = x_live([Src], Regs0), Regs = live_join_labels([Fail|List], D, Regs1), live_opt(Is, Regs, D, [I|Acc]); -live_opt([{select_tuple_arity,Src,Fail,{list,List}}=I|Is], Regs0, D, Acc) -> - Regs1 = x_live([Src], Regs0), - Regs = live_join_labels([Fail|List], D, Regs1), - live_opt(Is, Regs, D, [I|Acc]); -live_opt([{'try',_,Fail}=I|Is], Regs0, D, Acc) -> - Regs = live_join_label(Fail, D, Regs0), - live_opt(Is, Regs, D, [I|Acc]); live_opt([{try_case,_}=I|Is], _, D, Acc) -> live_opt(Is, live_call(1), D, [I|Acc]); live_opt([{loop_rec,_Fail,_Dst}=I|Is], _, D, Acc) -> live_opt(Is, 0, D, [I|Acc]); live_opt([timeout=I|Is], _, D, Acc) -> live_opt(Is, 0, D, [I|Acc]); +live_opt([{wait,_}=I|Is], _, D, Acc) -> + live_opt(Is, 0, D, [I|Acc]); +live_opt([{get_map_elements,Fail,Src,{list,List}}=I|Is], Regs0, D, Acc) -> + {Ss,Ds} = split_even(List), + Regs1 = x_live([Src|Ss], x_dead(Ds, Regs0)), + Regs = live_join_label(Fail, D, Regs1), + live_opt(Is, Regs, D, [I|Acc]); %% Transparent instructions - they neither use nor modify x registers. -live_opt([{bs_put_string,_,_}=I|Is], Regs, D, Acc) -> - live_opt(Is, Regs, D, [I|Acc]); live_opt([{deallocate,_}=I|Is], Regs, D, Acc) -> live_opt(Is, Regs, D, [I|Acc]); live_opt([{kill,_}=I|Is], Regs, D, Acc) -> @@ -809,7 +763,7 @@ live_opt([{try_end,_}=I|Is], Regs, D, Acc) -> live_opt(Is, Regs, D, [I|Acc]); live_opt([{loop_rec_end,_}=I|Is], Regs, D, Acc) -> live_opt(Is, Regs, D, [I|Acc]); -live_opt([{wait,_}=I|Is], Regs, D, Acc) -> +live_opt([{wait_timeout,_,nil}=I|Is], Regs, D, Acc) -> live_opt(Is, Regs, D, [I|Acc]); live_opt([{wait_timeout,_,{Tag,_}}=I|Is], Regs, D, Acc) when Tag =/= x -> live_opt(Is, Regs, D, [I|Acc]); @@ -817,23 +771,36 @@ live_opt([{line,_}=I|Is], Regs, D, Acc) -> live_opt(Is, Regs, D, [I|Acc]); %% The following instructions can occur if the "compilation" has been -%% started from a .S file using the 'asm' option. +%% started from a .S file using the 'from_asm' option. live_opt([{trim,_,_}=I|Is], Regs, D, Acc) -> live_opt(Is, Regs, D, [I|Acc]); -live_opt([{allocate,_,Live}=I|Is], _, D, Acc) -> - live_opt(Is, live_call(Live), D, [I|Acc]); -live_opt([{allocate_heap,_,_,Live}=I|Is], _, D, Acc) -> - live_opt(Is, live_call(Live), D, [I|Acc]); +live_opt([{'%',_}=I|Is], Regs, D, Acc) -> + live_opt(Is, Regs, D, [I|Acc]); +live_opt([{recv_set,_}=I|Is], Regs, D, Acc) -> + live_opt(Is, Regs, D, [I|Acc]); +live_opt([{recv_mark,_}=I|Is], Regs, D, Acc) -> + live_opt(Is, Regs, D, [I|Acc]); live_opt([], _, _, Acc) -> Acc. -live_opt_block([{set,[],[],{alloc,Live,_}}=I|Is], _, D, Acc) -> - live_opt_block(Is, live_call(Live), D, [I|Acc]); -live_opt_block([{set,Ds,Ss,Op}=I|Is], Regs0, D, Acc) -> - Regs = case Op of - {alloc,Live,_} -> live_call(Live); - _ -> x_live(Ss, x_dead(Ds, Regs0)) - end, +live_opt_block([{set,Ds,Ss,Op}=I0|Is], Regs0, D, Acc) -> + Regs1 = x_live(Ss, x_dead(Ds, Regs0)), + {I,Regs} = case Op of + {alloc,Live0,Alloc} -> + %% The life-time analysis used by the code generator + %% is sometimes too conservative, so it may be + %% possible to lower the number of live registers + %% based on the exact liveness information. + %% The main benefit is that more optimizations that + %% depend on liveness information (such as the + %% beam_bool and beam_dead passes) may be applied. + Live = live_regs(Regs1), + true = Live =< Live0, %Assertion. + I1 = {set,Ds,Ss,{alloc,Live,Alloc}}, + {I1,live_call(Live)}; + _ -> + {I0,Regs1} + end, case Ds of [{x,X}] -> case (not is_live(X, Regs0)) andalso Op =:= move of @@ -876,3 +843,8 @@ x_live([_|Rs], Regs) -> x_live(Rs, Regs); x_live([], Regs) -> Regs. is_live(X, Regs) -> ((Regs bsr X) band 1) =:= 1. + +split_even([], Ss, Ds) -> + {reverse(Ss),reverse(Ds)}; +split_even([S,D|Rs], Ss, Ds) -> + split_even(Rs, [S|Ss], [D|Ds]). |