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-rw-r--r--lib/compiler/src/beam_utils.erl155
1 files changed, 115 insertions, 40 deletions
diff --git a/lib/compiler/src/beam_utils.erl b/lib/compiler/src/beam_utils.erl
index 60221578bd..901588ee3b 100644
--- a/lib/compiler/src/beam_utils.erl
+++ b/lib/compiler/src/beam_utils.erl
@@ -25,7 +25,7 @@
is_not_used/3,usage/3,
empty_label_index/0,index_label/3,index_labels/1,replace_labels/4,
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_annos/1,combine_heap_needs/2,
anno_defs/1,
split_even/1
]).
@@ -95,7 +95,7 @@ is_killed_block({x,X}, [{set,_,_,{alloc,Live,_}}|_]) ->
X >= Live;
is_killed_block(R, [{set,Ds,Ss,_Op}|Is]) ->
not member(R, Ss) andalso (member(R, Ds) orelse is_killed_block(R, Is));
-is_killed_block(R, [{'%live',_,Regs}|Is]) ->
+is_killed_block(R, [{'%anno',{used,Regs}}|Is]) ->
case R of
{x,X} when (Regs bsr X) band 1 =:= 0 -> true;
_ -> is_killed_block(R, Is)
@@ -118,6 +118,7 @@ is_killed(R, Is, D) ->
St = #live{lbl=D,res=gb_trees:empty()},
case check_liveness(R, Is, St) of
{killed,_} -> true;
+ {exit_not_used,_} -> true;
{_,_} -> false
end.
@@ -130,6 +131,7 @@ is_killed_at(R, Lbl, D) when is_integer(Lbl) ->
St0 = #live{lbl=D,res=gb_trees:empty()},
case check_liveness_at(R, Lbl, St0) of
{killed,_} -> true;
+ {exit_not_used,_} -> true;
{_,_} -> false
end.
@@ -146,6 +148,7 @@ is_not_used(R, Is, D) ->
St = #live{lbl=D,res=gb_trees:empty()},
case check_liveness(R, Is, St) of
{used,_} -> false;
+ {exit_not_used,_} -> false;
{_,_} -> true
end.
@@ -267,7 +270,7 @@ 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,Regs} annotations at the beginning
+%% Also insert {used,Regs} annotations at the beginning
%% and end of each block.
-spec live_opt([instruction()]) -> [instruction()].
@@ -282,22 +285,22 @@ live_opt(Is0) ->
Bef ++ [Fi|live_opt(reverse(Is), 0, D, [])].
-%% delete_live_annos([Instruction]) -> [Instruction].
-%% Delete all live annotations.
+%% delete_annos([Instruction]) -> [Instruction].
+%% Delete all annotations.
--spec delete_live_annos([instruction()]) -> [instruction()].
+-spec delete_annos([instruction()]) -> [instruction()].
-delete_live_annos([{block,Bl0}|Is]) ->
- case delete_live_annos(Bl0) of
- [] -> delete_live_annos(Is);
- [_|_]=Bl -> [{block,Bl}|delete_live_annos(Is)]
+delete_annos([{block,Bl0}|Is]) ->
+ case delete_annos(Bl0) of
+ [] -> delete_annos(Is);
+ [_|_]=Bl -> [{block,Bl}|delete_annos(Is)]
end;
-delete_live_annos([{'%live',_,_}|Is]) ->
- delete_live_annos(Is);
-delete_live_annos([I|Is]) ->
- [I|delete_live_annos(Is)];
-delete_live_annos([]) -> [].
-
+delete_annos([{'%anno',_}|Is]) ->
+ delete_annos(Is);
+delete_annos([I|Is]) ->
+ [I|delete_annos(Is)];
+delete_annos([]) -> [].
+
%% combine_heap_needs(HeapNeed1, HeapNeed2) -> HeapNeed
%% Combine the heap need for two allocation instructions.
@@ -309,11 +312,11 @@ delete_live_annos([]) -> [].
combine_heap_needs(H1, H2) when is_integer(H1), is_integer(H2) ->
H1 + H2;
combine_heap_needs(H1, H2) ->
- combine_alloc_lists([H1,H2]).
+ {alloc,combine_alloc_lists([H1,H2])}.
%% anno_defs(Instructions) -> Instructions'
-%% Add {'%def',RegisterBitmap} annotations to the beginning of
+%% Add {def,RegisterBitmap} annotations to the beginning of
%% each block. Iff bit X is set in the the bitmap, it means
%% that {x,X} is defined when the block is entered.
@@ -347,6 +350,9 @@ split_even(Rs) -> split_even(Rs, [], []).
%%
%% killed - Reg is assigned or killed by an allocation instruction.
%% not_used - the value of Reg is not used, but Reg must not be garbage
+%% exit_not_used - the value of Reg is not used, but must not be garbage
+%% because the stack will be scanned because an
+%% exit BIF will raise an exception
%% used - Reg is used
check_liveness(R, [{block,Blk}|Is], St0) ->
@@ -370,6 +376,8 @@ check_liveness(R, [{test,_,{f,Fail},As}|Is], St0) ->
case check_liveness_at(R, Fail, St0) of
{killed,St1} ->
check_liveness(R, Is, St1);
+ {exit_not_used,St1} ->
+ check_liveness(R, Is, St1);
{not_used,St1} ->
not_used(check_liveness(R, Is, St1));
{used,_}=Used ->
@@ -389,6 +397,8 @@ check_liveness(R, [{jump,{f,F}}|_], St) ->
check_liveness_at(R, F, St);
check_liveness(R, [{case_end,Used}|_], St) ->
check_liveness_ret(R, Used, St);
+check_liveness(R, [{try_case_end,Used}|_], St) ->
+ check_liveness_ret(R, Used, St);
check_liveness(R, [{badmatch,Used}|_], St) ->
check_liveness_ret(R, Used, St);
check_liveness(_, [if_end|_], St) ->
@@ -432,7 +442,7 @@ check_liveness(R, [{bs_init,_,_,Live,Ss,Dst}|Is], St) ->
false ->
if
R =:= Dst -> {killed,St};
- true -> check_liveness(R, Is, St)
+ true -> not_used(check_liveness(R, Is, St))
end
end
end;
@@ -466,7 +476,7 @@ check_liveness(R, [{call_ext,Live,_}=I|Is], 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}
+ {exit_not_used,St}
end
end;
check_liveness(R, [{call_fun,Live}|Is], St) ->
@@ -514,16 +524,12 @@ check_liveness(R, [{make_fun2,_,_,_,NumFree}|Is], St) ->
{x,_} -> {killed,St};
{y,_} -> not_used(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, [{'catch'=Op,Y,Fail}|Is], St) ->
+ Set = {set,[Y],[],{try_catch,Op,Fail}},
+ check_liveness(R, [{block,[Set]}|Is], St);
+check_liveness(R, [{'try'=Op,Y,Fail}|Is], St) ->
+ Set = {set,[Y],[],{try_catch,Op,Fail}},
+ check_liveness(R, [{block,[Set]}|Is], St);
check_liveness(R, [{try_end,Y}|Is], St) ->
case R of
Y ->
@@ -584,6 +590,12 @@ check_liveness(R, [{get_map_elements,{f,Fail},S,{list,L}}|Is], St0) ->
check_liveness(R, [{put_map,F,Op,S,D,Live,{list,Puts}}|Is], St) ->
Set = {set,[D],[S|Puts],{alloc,Live,{put_map,Op,F}}},
check_liveness(R, [{block,[Set]}||Is], St);
+check_liveness(R, [{put_tuple,Ar,D}|Is], St) ->
+ Set = {set,[D],[],{put_tuple,Ar}},
+ check_liveness(R, [{block,[Set]}||Is], St);
+check_liveness(R, [{put_list,S1,S2,D}|Is], St) ->
+ Set = {set,[D],[S1,S2],put_list},
+ check_liveness(R, [{block,[Set]}||Is], St);
check_liveness(R, [{test_heap,N,Live}|Is], St) ->
I = {block,[{set,[],[],{alloc,Live,{nozero,nostack,N,[]}}}]},
check_liveness(R, [I|Is], St);
@@ -597,6 +609,12 @@ check_liveness(R, [remove_message|Is], St) ->
check_liveness(R, Is, St);
check_liveness({x,X}, [build_stacktrace|_], St) when X > 0 ->
{killed,St};
+check_liveness(R, [{recv_mark,_}|Is], St) ->
+ check_liveness(R, Is, St);
+check_liveness(R, [{recv_set,_}|Is], St) ->
+ check_liveness(R, Is, St);
+check_liveness(R, [{'%',_}|Is], St) ->
+ check_liveness(R, Is, St);
check_liveness(_R, Is, St) when is_list(Is) ->
%% Not implemented. Conservatively assume that the register is used.
{used,St}.
@@ -631,6 +649,7 @@ check_liveness_at(R, Lbl, #live{lbl=Ll,res=ResMemorized}=St0) ->
{Res,St#live{res=gb_trees:insert(Lbl, Res, St#live.res)}}
end.
+not_used({exit_not_used,St}) -> {not_used,St};
not_used({killed,St}) -> {not_used,St};
not_used({_,_}=Res) -> Res.
@@ -649,7 +668,7 @@ check_liveness_ret(_, _, St) -> {killed,St}.
%% alloc_used - Used only in an allocate instruction
%% used - Reg is explicitly used by an instruction
%%
-%% '%live' annotations are not allowed.
+%% Annotations are not allowed.
%%
%% (Unknown instructions will cause an exception.)
@@ -659,13 +678,30 @@ check_liveness_block({x,X}=R, [{set,Ds,Ss,{alloc,Live,Op}}|Is], St0) ->
{killed,St0};
true ->
case check_liveness_block_1(R, Ss, Ds, Op, Is, St0) of
- {killed,St} -> {not_used,St};
{transparent,St} -> {alloc_used,St};
- {_,_}=Res -> Res
+ {_,_}=Res -> not_used(Res)
end
end;
-check_liveness_block({y,_}=R, [{set,Ds,Ss,{alloc,_Live,Op}}|Is], St) ->
- check_liveness_block_1(R, Ss, Ds, Op, Is, St);
+check_liveness_block({y,_}=R, [{set,Ds,Ss,{alloc,_Live,Op}}|Is], St0) ->
+ case check_liveness_block_1(R, Ss, Ds, Op, Is, St0) of
+ {transparent,St} -> {alloc_used,St};
+ {_,_}=Res -> not_used(Res)
+ end;
+check_liveness_block({y,_}=R, [{set,Ds,Ss,{try_catch,_,Op}}|Is], St0) ->
+ case Ds of
+ [R] ->
+ {killed,St0};
+ _ ->
+ case check_liveness_block_1(R, Ss, Ds, Op, Is, St0) of
+ {exit_not_used,St} ->
+ {used,St};
+ {transparent,St} ->
+ %% Conservatively assumed that it is used.
+ {used,St};
+ {_,_}=Res ->
+ Res
+ end
+ end;
check_liveness_block(R, [{set,Ds,Ss,Op}|Is], St) ->
check_liveness_block_1(R, Ss, Ds, Op, Is, St);
check_liveness_block(_, [], St) -> {transparent,St}.
@@ -681,6 +717,11 @@ check_liveness_block_1(R, Ss, Ds, Op, Is, St0) ->
true -> {killed,St};
false -> check_liveness_block(R, Is, St)
end;
+ {exit_not_used,St} ->
+ case member(R, Ds) of
+ true -> {exit_not_used,St};
+ false -> check_liveness_block(R, Is, St)
+ end;
{not_used,St} ->
not_used(case member(R, Ds) of
true -> {killed,St};
@@ -824,9 +865,9 @@ 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),Regs0},
+ Live0 = make_anno({used,Regs0}),
{Bl,Regs} = live_opt_block(reverse(Bl0), Regs0, D, [Live0]),
- Live = {'%live',live_regs(Regs),Regs},
+ Live = make_anno({used,Regs}),
live_opt(Is, Regs, D, [{block,[Live|Bl]}|Acc]);
live_opt([build_stacktrace=I|Is], _, D, Acc) ->
live_opt(Is, live_call(1), D, [I|Acc]);
@@ -871,7 +912,8 @@ 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,_,Src,Fail,List}=I|Is], Regs0, D, Acc) ->
+live_opt([{select,_,Src,Fail,List}=I|Is], _, D, Acc) ->
+ Regs0 = 0,
Regs1 = x_live([Src], Regs0),
Regs = live_join_labels([Fail|List], D, Regs1),
live_opt(Is, Regs, D, [I|Acc]);
@@ -894,6 +936,25 @@ live_opt([{get_map_elements,Fail,Src,{list,List}}=I|Is], Regs0, D, Acc) ->
Regs1 = x_live([Src|Ss], x_dead(Ds, Regs0)),
Regs = live_join_label(Fail, D, Regs1),
live_opt(Is, Regs, D, [I|Acc]);
+live_opt([{gc_bif,N,F,R,As,Dst}=I|Is], Regs0, D, Acc) ->
+ Bl = [{set,[Dst],As,{alloc,R,{gc_bif,N,F}}}],
+ {_,Regs} = live_opt_block(Bl, Regs0, D, []),
+ live_opt(Is, Regs, D, [I|Acc]);
+live_opt([{bif,N,F,As,Dst}=I|Is], Regs0, D, Acc) ->
+ Bl = [{set,[Dst],As,{bif,N,F}}],
+ {_,Regs} = live_opt_block(Bl, Regs0, D, []),
+ live_opt(Is, Regs, D, [I|Acc]);
+live_opt([{get_tuple_element,Src,Idx,Dst}=I|Is], Regs0, D, Acc) ->
+ Bl = [{set,[Dst],[Src],{get_tuple_element,Idx}}],
+ {_,Regs} = live_opt_block(Bl, Regs0, D, []),
+ live_opt(Is, Regs, D, [I|Acc]);
+live_opt([{move,Src,Dst}=I|Is], Regs0, D, Acc) ->
+ Regs = x_live([Src], x_dead([Dst], Regs0)),
+ live_opt(Is, Regs, D, [I|Acc]);
+live_opt([{put_map,F,Op,S,Dst,R,{list,Puts}}=I|Is], Regs0, D, Acc) ->
+ Bl = [{set,[Dst],[S|Puts],{alloc,R,{put_map,Op,F}}}],
+ {_,Regs} = live_opt_block(Bl, Regs0, D, []),
+ live_opt(Is, Regs, D, [I|Acc]);
%% Transparent instructions - they neither use nor modify x registers.
live_opt([{deallocate,_}=I|Is], Regs, D, Acc) ->
@@ -910,6 +971,10 @@ live_opt([{wait_timeout,_,{Tag,_}}=I|Is], Regs, D, Acc) when Tag =/= x ->
live_opt(Is, Regs, D, [I|Acc]);
live_opt([{line,_}=I|Is], Regs, D, Acc) ->
live_opt(Is, Regs, D, [I|Acc]);
+live_opt([{'catch',_,_}=I|Is], Regs, D, Acc) ->
+ live_opt(Is, Regs, D, [I|Acc]);
+live_opt([{'try',_,_}=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 'from_asm' option.
@@ -940,7 +1005,7 @@ live_opt_block([{set,Ds,Ss,Op0}|Is], Regs0, D, Acc) ->
_ ->
live_opt_block(Is, Regs, D, [I|Acc])
end;
-live_opt_block([{'%live',_,_}|Is], Regs, D, Acc) ->
+live_opt_block([{'%anno',_}|Is], Regs, D, Acc) ->
live_opt_block(Is, Regs, D, Acc);
live_opt_block([], Regs, _, Acc) -> {Acc,Regs}.
@@ -1015,7 +1080,7 @@ defs([{bif,_,{f,Fail},_Src,Dst}=I|Is], Regs0, D) ->
[I|defs(Is, Regs, update_regs(Fail, Regs0, D))];
defs([{block,Block0}|Is], Regs0, D0) ->
{Block,Regs,D} = defs_list(Block0, Regs0, D0),
- [{block,[{'%def',Regs0}|Block]}|defs(Is, Regs, D)];
+ [{block,[make_anno({def,Regs0})|Block]}|defs(Is, Regs, D)];
defs([{bs_init,{f,L},_,_,_,Dst}=I|Is], Regs0, D) ->
Regs = def_regs([Dst], Regs0),
[I|defs(Is, Regs, update_regs(L, Regs, D))];
@@ -1205,3 +1270,13 @@ update_regs(L, Regs0, D) ->
all_defined(Live, Regs) ->
All = (1 bsl Live) - 1,
Regs band All =:= All.
+
+%%%
+%%% Utilities.
+%%%
+
+%% make_anno(Anno) -> WrappedAnno.
+%% Wrap an annotation term.
+
+make_anno(Anno) ->
+ {'%anno',Anno}.
generated by cgit v1.2.3 (git 2.25.1) at 2025-06-11 02:04:35 +0000