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-rw-r--r--lib/compiler/src/v3_codegen.erl283
1 files changed, 174 insertions, 109 deletions
diff --git a/lib/compiler/src/v3_codegen.erl b/lib/compiler/src/v3_codegen.erl
index 47a357c23d..34c67b16ca 100644
--- a/lib/compiler/src/v3_codegen.erl
+++ b/lib/compiler/src/v3_codegen.erl
@@ -3,16 +3,17 @@
%%
%% Copyright Ericsson AB 1999-2012. 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%
%%
@@ -43,7 +44,7 @@
-export([module/2]).
-import(lists, [member/2,keymember/3,keysort/2,keydelete/3,
- append/1,map/2,flatmap/2,filter/2,foldl/3,foldr/3,mapfoldl/3,
+ append/1,flatmap/2,filter/2,foldl/3,foldr/3,mapfoldl/3,
sort/1,reverse/1,reverse/2]).
-import(v3_life, [vdb_find/2]).
@@ -57,8 +58,7 @@
break, %Break label
recv, %Receive label
is_top_block, %Boolean: top block or not
- functable=gb_trees:empty(), %Gb tree of local functions:
- % {{Name,Arity},Label}
+ functable=#{}, %Map of local functions: {Name,Arity}=>Label
in_catch=false, %Inside a catch or not.
need_frame, %Need a stack frame.
ultimate_failure %Label for ultimate match failure.
@@ -69,10 +69,8 @@
stk=[], %Stack table
res=[]}). %Reserved regs: [{reserved,I,V}]
-module({Mod,Exp,Attr,Forms}, Options) ->
- put(?MODULE, Options),
+module({Mod,Exp,Attr,Forms}, _Options) ->
{Fs,St} = functions(Forms, {atom,Mod}),
- erase(?MODULE),
{ok,{Mod,Exp,Attr,Fs,St#cg.lcount}}.
functions(Forms, AtomMod) ->
@@ -123,24 +121,15 @@ cg_fun(Les, Hvs, Vdb, AtomMod, NameArity, Anno, St0) ->
put_reg(V, Reg)
end, [], Hvs),
stk=[]}, 0, Vdb),
- {B0,_Aft,St} = cg_list(Les, 0, Vdb, Bef,
+ {B,_Aft,St} = cg_list(Les, 0, Vdb, Bef,
St3#cg{bfail=0,
ultimate_failure=UltimateMatchFail,
is_top_block=true}),
- B = fix_bs_match_strings(B0),
{Name,Arity} = NameArity,
Asm = [{label,Fi},line(Anno),{func_info,AtomMod,{atom,Name},Arity},
{label,Fl}|B++[{label,UltimateMatchFail},if_end]],
{Asm,Fl,St}.
-fix_bs_match_strings([{test,bs_match_string,F,[Ctx,BinList]}|Is])
- when is_list(BinList) ->
- I = {test,bs_match_string,F,[Ctx,list_to_bitstring(BinList)]},
- [I|fix_bs_match_strings(Is)];
-fix_bs_match_strings([I|Is]) ->
- [I|fix_bs_match_strings(Is)];
-fix_bs_match_strings([]) -> [].
-
%% cg(Lkexpr, Vdb, StackReg, State) -> {[Ainstr],StackReg,State}.
%% Generate code for a kexpr.
%% Split function into two steps for clarity, not efficiency.
@@ -210,7 +199,7 @@ need_heap_0([], H, Acc) ->
need_heap_1(#l{ke={set,_,{binary,_}},i=I}, H) ->
{need_heap_need(I, H),0};
-need_heap_1(#l{ke={set,_,{map,_,_}},i=I}, H) ->
+need_heap_1(#l{ke={set,_,{map,_,_,_}},i=I}, H) ->
{need_heap_need(I, H),0};
need_heap_1(#l{ke={set,_,Val}}, H) ->
%% Just pass through adding to needed heap.
@@ -586,7 +575,7 @@ top_level_block(Keis, Bef, MaxRegs, _St) ->
(return) ->
[{deallocate,FrameSz},return];
(Tuple) when is_tuple(Tuple) ->
- [turn_yregs(tuple_size(Tuple), Tuple, MaxY)];
+ [turn_yregs(Tuple, MaxY)];
(Other) ->
[Other]
end, Keis),
@@ -598,14 +587,49 @@ top_level_block(Keis, Bef, MaxRegs, _St) ->
%% catches work. The code generation algorithm gives a lower register
%% number to the outer catch, which is wrong.
-turn_yregs(0, Tp, _) -> Tp;
-turn_yregs(El, Tp, MaxY) ->
- turn_yregs(El-1,setelement(El,Tp,turn_yreg(element(El,Tp),MaxY)),MaxY).
-
-turn_yreg({yy,YY},MaxY) -> {y,MaxY-YY};
-turn_yreg({list,Ls},MaxY) -> {list, turn_yreg(Ls,MaxY)};
-turn_yreg(Ts,MaxY) when is_list(Ts) -> [turn_yreg(T,MaxY)||T<-Ts];
-turn_yreg(Other,_MaxY) -> Other.
+turn_yregs({call,_,_}=I, _MaxY) -> I;
+turn_yregs({call_ext,_,_}=I, _MaxY) -> I;
+turn_yregs({jump,_}=I, _MaxY) -> I;
+turn_yregs({label,_}=I, _MaxY) -> I;
+turn_yregs({line,_}=I, _MaxY) -> I;
+turn_yregs({test_heap,_,_}=I, _MaxY) -> I;
+turn_yregs({bif,Op,F,A,B}, MaxY) ->
+ {bif,Op,F,turn_yreg(A, MaxY),turn_yreg(B, MaxY)};
+turn_yregs({gc_bif,Op,F,Live,A,B}, MaxY) when is_integer(Live) ->
+ {gc_bif,Op,F,Live,turn_yreg(A, MaxY),turn_yreg(B, MaxY)};
+turn_yregs({get_tuple_element,S,N,D}, MaxY) ->
+ {get_tuple_element,turn_yreg(S, MaxY),N,turn_yreg(D, MaxY)};
+turn_yregs({put_tuple,Arity,D}, MaxY) ->
+ {put_tuple,Arity,turn_yreg(D, MaxY)};
+turn_yregs({select_val,R,F,L}, MaxY) ->
+ {select_val,turn_yreg(R, MaxY),F,L};
+turn_yregs({test,Op,F,L}, MaxY) ->
+ {test,Op,F,turn_yreg(L, MaxY)};
+turn_yregs({test,Op,F,Live,A,B}, MaxY) when is_integer(Live) ->
+ {test,Op,F,Live,turn_yreg(A, MaxY),turn_yreg(B, MaxY)};
+turn_yregs({Op,A}, MaxY) ->
+ {Op,turn_yreg(A, MaxY)};
+turn_yregs({Op,A,B}, MaxY) ->
+ {Op,turn_yreg(A, MaxY),turn_yreg(B, MaxY)};
+turn_yregs({Op,A,B,C}, MaxY) ->
+ {Op,turn_yreg(A, MaxY),turn_yreg(B, MaxY),turn_yreg(C, MaxY)};
+turn_yregs(Tuple, MaxY) ->
+ turn_yregs(tuple_size(Tuple), Tuple, MaxY).
+
+turn_yregs(1, Tp, _) ->
+ Tp;
+turn_yregs(N, Tp, MaxY) ->
+ E = turn_yreg(element(N, Tp), MaxY),
+ turn_yregs(N-1, setelement(N, Tp, E), MaxY).
+
+turn_yreg({yy,YY}, MaxY) ->
+ {y,MaxY-YY};
+turn_yreg({list,Ls},MaxY) ->
+ {list,turn_yreg(Ls, MaxY)};
+turn_yreg([_|_]=Ts, MaxY) ->
+ [turn_yreg(T, MaxY) || T <- Ts];
+turn_yreg(Other, _MaxY) ->
+ Other.
%% select_cg(Sclause, V, TypeFail, ValueFail, StackReg, State) ->
%% {Is,StackReg,State}.
@@ -643,19 +667,13 @@ select_val_cg(tuple, R, [Arity,{f,Lbl}], Tf, Vf, [{label,Lbl}|Sis]) ->
[{test,is_tuple,{f,Tf},[R]},{test,test_arity,{f,Vf},[R,Arity]}|Sis];
select_val_cg(tuple, R, Vls, Tf, Vf, Sis) ->
[{test,is_tuple,{f,Tf},[R]},{select_tuple_arity,R,{f,Vf},{list,Vls}}|Sis];
-select_val_cg(map, R, [_Val,{f,Lbl}], Fail, Fail, [{label,Lbl}|Sis]) ->
- [{test,is_map,{f,Fail},[R]}|Sis];
-select_val_cg(map, R, [_Val,{f,Lbl}|_], Tf, _Vf, [{label,Lbl}|Sis]) ->
- [{test,is_map,{f,Tf},[R]}|Sis];
select_val_cg(Type, R, [Val, {f,Lbl}], Fail, Fail, [{label,Lbl}|Sis]) ->
[{test,is_eq_exact,{f,Fail},[R,{Type,Val}]}|Sis];
select_val_cg(Type, R, [Val, {f,Lbl}], Tf, Vf, [{label,Lbl}|Sis]) ->
[{test,select_type_test(Type),{f,Tf},[R]},
{test,is_eq_exact,{f,Vf},[R,{Type,Val}]}|Sis];
select_val_cg(Type, R, Vls0, Tf, Vf, Sis) ->
- Vls1 = map(fun ({f,_Lbl} = F) -> F;
- (Value) -> {Type,Value}
- end, Vls0),
+ Vls1 = [case Value of {f,_Lbl} -> Value; _ -> {Type,Value} end || Value <- Vls0],
[{test,select_type_test(Type),{f,Tf},[R]}, {select_val,R,{f,Vf},{list,Vls1}}|Sis].
select_type_test(integer) -> is_integer;
@@ -688,22 +706,37 @@ select_nil(#l{ke={val_clause,nil,B}}, V, Tf, Vf, Bef, St0) ->
select_binary(#l{ke={val_clause,{binary,{var,V}},B},i=I,vdb=Vdb},
V, Tf, Vf, Bef, St0) ->
Int0 = clear_dead(Bef#sr{reg=Bef#sr.reg}, I, Vdb),
- {Bis,Aft,St1} = match_cg(B, Vf, Int0, St0),
+ {Bis0,Aft,St1} = match_cg(B, Vf, Int0, St0),
CtxReg = fetch_var(V, Int0),
Live = max_reg(Bef#sr.reg),
- {[{test,bs_start_match2,{f,Tf},Live,[CtxReg,V],CtxReg},
- {bs_save2,CtxReg,{V,V}}|Bis],
- Aft,St1};
+ Bis1 = [{test,bs_start_match2,{f,Tf},Live,[CtxReg,V],CtxReg},
+ {bs_save2,CtxReg,{V,V}}|Bis0],
+ Bis = finish_select_binary(Bis1),
+ {Bis,Aft,St1};
select_binary(#l{ke={val_clause,{binary,{var,Ivar}},B},i=I,vdb=Vdb},
V, Tf, Vf, Bef, St0) ->
Regs = put_reg(Ivar, Bef#sr.reg),
Int0 = clear_dead(Bef#sr{reg=Regs}, I, Vdb),
- {Bis,Aft,St1} = match_cg(B, Vf, Int0, St0),
+ {Bis0,Aft,St1} = match_cg(B, Vf, Int0, St0),
CtxReg = fetch_var(Ivar, Int0),
Live = max_reg(Bef#sr.reg),
- {[{test,bs_start_match2,{f,Tf},Live,[fetch_var(V, Bef),Ivar],CtxReg},
- {bs_save2,CtxReg,{Ivar,Ivar}}|Bis],
- Aft,St1}.
+ Bis1 = [{test,bs_start_match2,{f,Tf},Live,[fetch_var(V, Bef),Ivar],CtxReg},
+ {bs_save2,CtxReg,{Ivar,Ivar}}|Bis0],
+ Bis = finish_select_binary(Bis1),
+ {Bis,Aft,St1}.
+
+finish_select_binary([{bs_save2,R,Point}=I,{bs_restore2,R,Point}|Is]) ->
+ [I|finish_select_binary(Is)];
+finish_select_binary([{bs_save2,R,Point}=I,{test,is_eq_exact,_,_}=Test,
+ {bs_restore2,R,Point}|Is]) ->
+ [I,Test|finish_select_binary(Is)];
+finish_select_binary([{test,bs_match_string,F,[Ctx,BinList]}|Is])
+ when is_list(BinList) ->
+ I = {test,bs_match_string,F,[Ctx,list_to_bitstring(BinList)]},
+ [I|finish_select_binary(Is)];
+finish_select_binary([I|Is]) ->
+ [I|finish_select_binary(Is)];
+finish_select_binary([]) -> [].
%% New instructions for selection of binary segments.
@@ -928,7 +961,7 @@ select_extract_tuple(Src, Vs, I, Vdb, Bef, St) ->
select_map(Scs, V, Tf, Vf, Bef, St0) ->
Reg = fetch_var(V, Bef),
{Is,Aft,St1} =
- match_fmf(fun(#l{ke={val_clause,{map,_,Es},B},i=I,vdb=Vdb}, Fail, St1) ->
+ match_fmf(fun(#l{ke={val_clause,{map,exact,_,Es},B},i=I,vdb=Vdb}, Fail, St1) ->
select_map_val(V, Es, B, Fail, I, Vdb, Bef, St1)
end, Vf, St0, Scs),
{[{test,is_map,{f,Tf},[Reg]}|Is],Aft,St1}.
@@ -947,27 +980,34 @@ select_extract_map(Src, Vs, Fail, I, Vdb, Bef, St) ->
%% Assume keys are term-sorted
Rsrc = fetch_var(Src, Bef),
- {{HasKs,GetVs},Aft} = lists:foldr(fun
- ({map_pair,Key,{var,V}},{{HasKsi,GetVsi},Int0}) ->
+ {{HasKs,GetVs,HasVarKs,GetVarVs},Aft} = lists:foldr(fun
+ ({map_pair,{var,K},{var,V}},{{HasKsi,GetVsi,HasVarVsi,GetVarVsi},Int0}) ->
+ case vdb_find(V, Vdb) of
+ {V,_,L} when L =< I ->
+ RK = fetch_var(K,Int0),
+ {{HasKsi,GetVsi,[RK|HasVarVsi],GetVarVsi},Int0};
+ _Other ->
+ Reg1 = put_reg(V, Int0#sr.reg),
+ Int1 = Int0#sr{reg=Reg1},
+ RK = fetch_var(K,Int0),
+ RV = fetch_reg(V,Reg1),
+ {{HasKsi,GetVsi,HasVarVsi,[[RK,RV]|GetVarVsi]},Int1}
+ end;
+ ({map_pair,Key,{var,V}},{{HasKsi,GetVsi,HasVarVsi,GetVarVsi},Int0}) ->
case vdb_find(V, Vdb) of
{V,_,L} when L =< I ->
- {{[Key|HasKsi],GetVsi},Int0};
+ {{[Key|HasKsi],GetVsi,HasVarVsi,GetVarVsi},Int0};
_Other ->
Reg1 = put_reg(V, Int0#sr.reg),
Int1 = Int0#sr{reg=Reg1},
- {{HasKsi,[Key,fetch_reg(V, Reg1)|GetVsi]},Int1}
+ {{HasKsi,[Key,fetch_reg(V, Reg1)|GetVsi],HasVarVsi,GetVarVsi},Int1}
end
- end, {{[],[]},Bef}, Vs),
-
- Code = case {HasKs,GetVs} of
- {HasKs,[]} ->
- [{test,has_map_fields,{f,Fail},Rsrc,{list,HasKs}}];
- {[],GetVs} ->
- [{get_map_elements, {f,Fail},Rsrc,{list,GetVs}}];
- {HasKs,GetVs} ->
- [{test,has_map_fields,{f,Fail},Rsrc,{list,HasKs}},
- {get_map_elements, {f,Fail},Rsrc,{list,GetVs}}]
- end,
+ end, {{[],[],[],[]},Bef}, Vs),
+
+ Code = [{test,has_map_fields,{f,Fail},Rsrc,{list,HasKs}} || HasKs =/= []] ++
+ [{test,has_map_fields,{f,Fail},Rsrc,{list,[K]}} || K <- HasVarKs] ++
+ [{get_map_elements, {f,Fail},Rsrc,{list,GetVs}} || GetVs =/= []] ++
+ [{get_map_elements, {f,Fail},Rsrc,{list,[K,V]}} || [K,V] <- GetVarVs],
{Code, Aft, St}.
@@ -1038,7 +1078,7 @@ protected_cg(Ts, Rs, _Fail, I, Vdb, Bef, St0) ->
St2#cg{bfail=Pfail}),
%%ok = io:fwrite("cg ~w: ~p~n", [?LINE,{Rs,I,Vdb,Aft}]),
%% Set return values to false.
- Mis = map(fun ({var,V}) -> {move,{atom,false},fetch_var(V, Aft)} end, Rs),
+ Mis = [{move,{atom,false},fetch_var(V,Aft)}||{var,V} <- Rs],
{Tis ++ [{jump,{f,Psucc}},
{label,Pfail}] ++ Mis ++ [{label,Psucc}],
Aft,St3#cg{bfail=St0#cg.bfail}}.
@@ -1221,13 +1261,12 @@ enter_line(_, _, _) ->
local_func_label(Name, Arity, St) ->
local_func_label({Name,Arity}, St).
-local_func_label(Key, #cg{functable=Tab}=St0) ->
- case gb_trees:lookup(Key, Tab) of
- {value,Label} ->
- {Label,St0};
- none ->
+local_func_label(Key, #cg{functable=Map}=St0) ->
+ case Map of
+ #{Key := Label} -> {Label,St0};
+ _ ->
{Label,St} = new_label(St0),
- {Label,St#cg{functable=gb_trees:insert(Key, Label, Tab)}}
+ {Label,St#cg{functable=Map#{Key => Label}}}
end.
%% need_stack_frame(State) -> State'
@@ -1504,7 +1543,8 @@ set_cg([{var,R}], {binary,Segs}, Le, Vdb, Bef,
%% Now generate the complete code for constructing the binary.
Code = cg_binary(PutCode, Target, Temp, Fail, MaxRegs, Le#l.a),
{Sis++Code,Aft,St};
-set_cg([{var,R}], {map,Op,Map,Es}, Le, Vdb, Bef,
+% Map single variable key
+set_cg([{var,R}], {map,Op,Map,[{map_pair,{var,_}=K,V}]}, Le, Vdb, Bef,
#cg{in_catch=InCatch,bfail=Bfail}=St) ->
Fail = {f,Bfail},
@@ -1516,17 +1556,47 @@ set_cg([{var,R}], {map,Op,Map,Es}, Le, Vdb, Bef,
SrcReg = cg_reg_arg(Map,Int0),
Line = line(Le#l.a),
- %% The instruction needs to store keys in term sorted order
- %% All keys has to be unique here
- Pairs = map_pair_strip_and_termsort(Es),
+ List = [cg_reg_arg(K,Int0),cg_reg_arg(V,Int0)],
+
+ Live = max_reg(Bef#sr.reg),
+
+ %% The target register can reuse one of the source registers.
+ Aft0 = clear_dead(Int0, Le#l.i, Vdb),
+ Aft = Aft0#sr{reg=put_reg(R, Aft0#sr.reg)},
+ Target = fetch_reg(R, Aft#sr.reg),
+
+ I = case Op of
+ assoc -> put_map_assoc;
+ exact -> put_map_exact
+ end,
+ {Sis++[Line]++[{I,Fail,SrcReg,Target,Live,{list,List}}],Aft,St};
+
+% Map (possibly) multiple literal keys
+set_cg([{var,R}], {map,Op,Map,Es}, Le, Vdb, Bef,
+ #cg{in_catch=InCatch,bfail=Bfail}=St) ->
+
+ %% assert key literals
+ [] = [Var||{map_pair,{var,_}=Var,_} <- Es],
+
+ Fail = {f,Bfail},
+ {Sis,Int0} =
+ case InCatch of
+ true -> adjust_stack(Bef, Le#l.i, Le#l.i+1, Vdb);
+ false -> {[],Bef}
+ end,
+ SrcReg = cg_reg_arg(Map,Int0),
+ Line = line(Le#l.a),
%% fetch registers for values to be put into the map
+ Pairs = [{K,V} || {_,K,V} <- Es],
List = flatmap(fun({K,V}) -> [K,cg_reg_arg(V,Int0)] end, Pairs),
Live = max_reg(Bef#sr.reg),
- Int1 = Int0#sr{reg=put_reg(R, Int0#sr.reg)},
- Aft = clear_dead(Int1, Le#l.i, Vdb),
- Target = fetch_reg(R, Int1#sr.reg),
+
+ %% The target register can reuse one of the source registers.
+ Aft0 = clear_dead(Int0, Le#l.i, Vdb),
+ Aft = Aft0#sr{reg=put_reg(R, Aft0#sr.reg)},
+ Target = fetch_reg(R, Aft#sr.reg),
I = case Op of
assoc -> put_map_assoc;
@@ -1545,16 +1615,6 @@ set_cg([{var,R}], Con, Le, Vdb, Bef, St) ->
end,
{Ais,clear_dead(Int, Le#l.i, Vdb),St}.
-map_pair_strip_and_termsort(Es) ->
- %% format in
- %% [{map_pair,K,V}]
- %% where K is for example {integer, 1} and we want to sort on 1.
- Ls = [{K,V}||{_,K,V}<-Es],
- lists:sort(fun ({{_,A},_}, {{_,B},_}) -> erts_internal:cmp_term(A,B) =< 0;
- ({nil,_}, {{_,B},_}) -> [] =< B;
- ({{_,A},_}, {nil,_}) -> A =< []
- end, Ls).
-
%%%
%%% Code generation for constructing binaries.
%%%
@@ -1929,25 +1989,28 @@ clear_dead(Sr, Until, Vdb) ->
stk=clear_dead_stk(Sr#sr.stk, Until, Vdb)}.
clear_dead_reg(Sr, Until, Vdb) ->
- Reg = map(fun ({_I,V} = IV) ->
- case vdb_find(V, Vdb) of
- {V,_,L} when L > Until -> IV;
- _ -> free %Remove anything else
- end;
- ({reserved,_I,_V} = Reserved) -> Reserved;
- (free) -> free
- end, Sr#sr.reg),
+ Reg = [case R of
+ {_I,V} = IV ->
+ case vdb_find(V, Vdb) of
+ {V,_,L} when L > Until -> IV;
+ _ -> free %Remove anything else
+ end;
+ {reserved,_I,_V} = Reserved -> Reserved;
+ free -> free
+ end || R <- Sr#sr.reg],
reserve(Sr#sr.res, Reg, Sr#sr.stk).
clear_dead_stk(Stk, Until, Vdb) ->
- map(fun ({V} = T) ->
- case vdb_find(V, Vdb) of
- {V,_,L} when L > Until -> T;
- _ -> dead %Remove anything else
- end;
- (free) -> free;
- (dead) -> dead
- end, Stk).
+ [case S of
+ {V} = T ->
+ case vdb_find(V, Vdb) of
+ {V,_,L} when L > Until -> T;
+ _ -> dead %Remove anything else
+ end;
+ free -> free;
+ dead -> dead
+ end || S <- Stk].
+
%% sr_merge(Sr1, Sr2) -> Sr.
%% Merge two stack/register states keeping the longest of both stack
@@ -2077,9 +2140,11 @@ put_stack(Val, [free|Stk]) -> [{Val}|Stk];
put_stack(Val, [NotFree|Stk]) -> [NotFree|put_stack(Val, Stk)].
put_stack_carefully(Val, Stk0) ->
- case catch put_stack_carefully1(Val, Stk0) of
- error -> error;
- Stk1 when is_list(Stk1) -> Stk1
+ try
+ put_stack_carefully1(Val, Stk0)
+ catch
+ throw:error ->
+ error
end.
put_stack_carefully1(_, []) -> throw(error);