Generate intermediate code that is easier to optimize

Instead of generating:

   {assign,Dst,"element(2, Val)"}

generate:

   {call,erlang,element,[2,{var,"Val"}],Dst}

The latter expression is easier to understand since there is no
need to parse a string which may contain an arbitrary expression.

While at it, also discontinue the practice to treat "naked"
atoms as variables. A variable must always be given as {var,String}.

3 files changed, 66 insertions, 66 deletions

diff --git a/lib/asn1/src/asn1ct_constructed_per.erl b/lib/asn1/src/asn1ct_constructed_per.erl
index d1e0b8d9ed..c224f4c9fa 100644
--- a/lib/asn1/src/asn1ct_constructed_per.erl
+++ b/lib/asn1/src/asn1ct_constructed_per.erl
@@ -79,7 +79,7 @@ gen_encode_constructed_imm(Erule, Typename, #type{}=D) ->
 		[]
 	end,
     Aligned = is_aligned(Erule),
-    Value0 = asn1ct_gen:mk_var(asn1ct_name:curr(val)),
+    Value0 = make_var(val),
     Optionals = optionals(to_textual_order(CompList)),
     ImmOptionals = [asn1ct_imm:per_enc_optional(Value0, Opt, Aligned) ||
 		       Opt <- Optionals],
@@ -87,7 +87,7 @@ gen_encode_constructed_imm(Erule, Typename, #type{}=D) ->
     ExtImm = case Ext of
 		 {ext,ExtPos,NumExt} when NumExt > 0 ->
 		     gen_encode_extaddgroup(CompList),
-		     Value = asn1ct_gen:mk_var(asn1ct_name:curr(val)),
+		     Value = make_var(val),
 		     asn1ct_imm:per_enc_extensions(Value, ExtPos,
 						   NumExt, Aligned);
 		 _ ->
@@ -106,19 +106,17 @@ gen_encode_constructed_imm(Erule, Typename, #type{}=D) ->
 				   c_index=N,
 				   usedclassfield=UniqueFieldName,
 				   uniqueclassfield=UniqueFieldName,
-				   valueindex=ValueIndex
+				   valueindex=ValueIndex0
 				  } -> %% N is index of attribute that determines constraint
 		{Module,ObjSetName} = ObjectSet,
 		#typedef{typespec=#'ObjectSet'{gen=Gen}} =
 		    asn1_db:dbget(Module, ObjSetName),
 		case Gen of
 		    true ->
-			ObjectEncode = 
-			    asn1ct_gen:un_hyphen_var(lists:concat(['Obj',AttrN])),
-			El = make_element(N+1, asn1ct_gen:mk_var(asn1ct_name:curr(val))),
-			ValueMatch = value_match(ValueIndex, El),
-			ObjSetImm0 = [{assign,{var,ObjectEncode},ValueMatch}],
-			{{AttrN,ObjectEncode},ObjSetImm0};
+			ValueIndex = ValueIndex0 ++ [{N+1,top}],
+			Val = make_var(val),
+			{ObjSetImm0,Dst} = enc_dig_out_value(ValueIndex, Val),
+			{{AttrN,Dst},ObjSetImm0};
 		    false ->
 			{false,[]}
 		end;
@@ -128,7 +126,7 @@ gen_encode_constructed_imm(Erule, Typename, #type{}=D) ->
 			%% when the simpletableattributes was at an outer
 			%% level and the objfun has been passed through the
 			%% function call
-			{{"got objfun through args","ObjFun"},[]};
+			{{"got objfun through args",{var,"ObjFun"}},[]};
 		    _ ->
 			{false,[]}
 		end
@@ -136,7 +134,7 @@ gen_encode_constructed_imm(Erule, Typename, #type{}=D) ->
     ImmSetExt =
 	case Ext of
 	    {ext,_Pos,NumExt2} when NumExt2 > 0 ->
-		asn1ct_imm:per_enc_extension_bit('Extensions', Aligned);
+		asn1ct_imm:per_enc_extension_bit({var,"Extensions"}, Aligned);
 	    {ext,_Pos,_} ->
 		asn1ct_imm:per_enc_extension_bit([], Aligned);
 	    _ ->
@@ -540,7 +538,7 @@ gen_encode_choice_imm(Erule, TopType, #type{def={'CHOICE',CompList}}) ->
     Aligned = is_aligned(Erule),
     Cs = gen_enc_choice(Erule, TopType, CompList, Ext),
     [{assign,{expr,"{ChoiceTag,ChoiceVal}"},"Val"}|
-     asn1ct_imm:per_enc_choice('ChoiceTag', Cs, Aligned)].
+     asn1ct_imm:per_enc_choice({var,"ChoiceTag"}, Cs, Aligned)].
 
 gen_decode_choice(Erules,Typename,D) when is_record(D,type) ->
     asn1ct_name:start(),
@@ -568,7 +566,8 @@ gen_encode_sof_imm(Erule, Typename, SeqOrSetOf, #type{}=D) ->
     Currmod = get(currmod),
     Imm0 = case asn1ct_gen:type(Conttype) of
 	       {primitive,bif} ->
-		   asn1ct_gen_per:gen_encode_prim_imm('Comp', ComponentType, Aligned);
+		   asn1ct_gen_per:gen_encode_prim_imm({var,"Comp"},
+						      ComponentType, Aligned);
 	       {constructed,bif} ->
 		   TypeName = [Constructed_Suffix|Typename],
 		   Enc = enc_func(asn1ct_gen:list2name(TypeName)),
@@ -583,11 +582,12 @@ gen_encode_sof_imm(Erule, Typename, SeqOrSetOf, #type{}=D) ->
 	       #'Externaltypereference'{module=EMod,type=Ename} ->
 		   [{apply,{EMod,enc_func(Ename),CompType},[{var,"Comp"}]}];
 	       'ASN1_OPEN_TYPE' ->
-		   asn1ct_gen_per:gen_encode_prim_imm('Comp',
+		   asn1ct_gen_per:gen_encode_prim_imm({var,"Comp"},
 						      #type{def='ASN1_OPEN_TYPE'},
 						      Aligned)
 	   end,
-    asn1ct_imm:per_enc_sof('Val', D#type.constraint, 'Comp', Imm0, Aligned).
+    asn1ct_imm:per_enc_sof({var,"Val"}, D#type.constraint, 'Comp',
+			   Imm0, Aligned).
 
 gen_decode_sof(Erules, Typename, SeqOrSetOf, #type{}=D) ->
     asn1ct_name:start(),
@@ -871,8 +871,8 @@ gen_enc_components_call1(Erule,TopType,
 	    CanonicalNum ->
 		CanonicalNum
 	end,
-    Element0 = make_element(TermNo+1, asn1ct_gen:mk_var(asn1ct_name:curr(val))),
-    {Imm0,Element} = asn1ct_imm:enc_bind_var(Element0),
+    Val = make_var(val),
+    {Imm0,Element} = asn1ct_imm:enc_element(TermNo+1, Val),
     Imm1 = gen_enc_line_imm(Erule, TopType, Cname, Type, Element, DynamicEnc, Ext),
     Category = case {Prop,Ext} of
 		   {'OPTIONAL',_} ->
@@ -967,11 +967,9 @@ gen_enc_line_imm_1(Erule, TopType, Cname, Type, Element, DynamicEnc) ->
 	    CurrMod = get(currmod),
 	    case asn1ct_gen:type(Atype) of
 		#'Externaltypereference'{module=CurrMod,type=EType} ->
-		    [{apply,{local,enc_func(EType),Atype},
-		      [{expr,Element}]}];
+		    [{apply,{local,enc_func(EType),Atype},[Element]}];
 		#'Externaltypereference'{module=Mod,type=EType} ->
-		    [{apply,{Mod,enc_func(EType),Atype},
-		      [{expr,Element}]}];
+		    [{apply,{Mod,enc_func(EType),Atype},[Element]}];
 		{primitive,bif} ->
 		    asn1ct_gen_per:gen_encode_prim_imm(Element, Type, Aligned);
 		'ASN1_OPEN_TYPE' ->
@@ -990,11 +988,9 @@ gen_enc_line_imm_1(Erule, TopType, Cname, Type, Element, DynamicEnc) ->
 		    Enc = enc_func(asn1ct_gen:list2name(NewTypename)),
 		    case {Type#type.tablecinf,DynamicEnc} of
 			{[{objfun,_}|_R],{_,EncFun}} ->
-			    [{apply,{local,Enc,Type},
-			      [{expr,Element},{var,EncFun}]}];
+			    [{apply,{local,Enc,Type},[Element,EncFun]}];
 			_ ->
-			    [{apply,{local,Enc,Type},
-			      [{expr,Element}]}]
+			    [{apply,{local,Enc,Type},[Element]}]
 		    end
 	    end
     end.
@@ -1027,7 +1023,7 @@ enc_var_type_call(Erule, Name, RestFieldNames,
 		  emit([".",nl])
 	  end,
     Prefix = lists:concat(["enc_os_",Name]),
-    [{call_gen,Prefix,Key,Gen,Lambda,[{var,atom_to_list(Val)},{var,Fun}]}].
+    [{call_gen,Prefix,Key,Gen,Lambda,[Val,Fun]}].
 
 fix_object_code(Name, [{Name,B}|_], _ClassFields) ->
     B;
@@ -1070,7 +1066,7 @@ enc_objset_imm(Erule, Component, ObjSet, RestFieldNames, Extensible) ->
 enc_obj(Erule, Obj, RestFieldNames0, Aligned) ->
     case Obj of
 	#typedef{name={primitive,bif},typespec=Def} ->
-	    asn1ct_gen_per:gen_encode_prim_imm('Val', Def, Aligned);
+	    asn1ct_gen_per:gen_encode_prim_imm({var,"Val"}, Def, Aligned);
 	#typedef{name={constructed,bif},typespec=Def} ->
 	    InnerType = asn1ct_gen:get_inner(Def#type.def),
 	    case InnerType of
@@ -1542,12 +1538,12 @@ gen_enc_choices([H|T], Erule, TopType, Pos, Constr, Ext) ->
 	    no -> 
 		case Type#type.tablecinf of
 		    [{objfun,_}|_] ->
-			{"got objfun through args","ObjFun"};
+			{"got objfun through args",{var,"ObjFun"}};
 		    _ ->
 			false
 		end;
 	    _ ->
-		{no_attr,"ObjFun"}
+		{no_attr,{var,"ObjFun"}}
 	end,
     DoExt = case Constr of
 		ext -> Ext;
@@ -1563,7 +1559,7 @@ gen_enc_choices([H|T], Erule, TopType, Pos, Constr, Ext) ->
 		  [{put_bits,0,1,[1]}|
 		   asn1ct_imm:per_enc_integer(Pos, Constr, Aligned)]
 	  end,
-    Body = gen_enc_line_imm(Erule, TopType, Cname, Type, 'ChoiceVal',
+    Body = gen_enc_line_imm(Erule, TopType, Cname, Type, {var,"ChoiceVal"},
 			    EncObj, DoExt),
     Imm = Tag ++ Body,
     [{Cname,Imm}|gen_enc_choices(T, Erule, TopType, Pos+1, Constr, Ext)];
@@ -1780,3 +1776,13 @@ value_match1(Value,[],Acc,Depth) ->
     Acc ++ Value ++ lists:concat(lists:duplicate(Depth,")"));
 value_match1(Value,[{VI,_}|VIs],Acc,Depth) ->
     value_match1(Value,VIs,Acc++lists:concat(["element(",VI,","]),Depth+1).
+
+enc_dig_out_value([], Value) ->
+    {[],Value};
+enc_dig_out_value([{N,_}|T], Value) ->
+    {Imm0,Dst0} = enc_dig_out_value(T, Value),
+    {Imm,Dst} = asn1ct_imm:enc_element(N, Dst0),
+    {Imm0++Imm,Dst}.
+
+make_var(Base) ->
+    {var,atom_to_list(asn1ct_gen:mk_var(asn1ct_name:curr(Base)))}.
diff --git a/lib/asn1/src/asn1ct_gen_per.erl b/lib/asn1/src/asn1ct_gen_per.erl
index f3389be6b3..7ba649c874 100644
--- a/lib/asn1/src/asn1ct_gen_per.erl
+++ b/lib/asn1/src/asn1ct_gen_per.erl
@@ -99,7 +99,7 @@ gen_encode_user(Erules,D) when is_record(D,typedef) ->
 
 
 gen_encode_prim(Erules, D) ->
-    Value = asn1ct_gen:mk_var(asn1ct_name:curr(val)),
+    Value = {var,atom_to_list(asn1ct_gen:mk_var(asn1ct_name:curr(val)))},
     gen_encode_prim(Erules, D, Value).
 
 gen_encode_prim(Erules, #type{}=D, Value) ->
@@ -149,10 +149,10 @@ gen_encode_prim_imm(Val, #type{def=Type0,constraint=Constraint}, Aligned) ->
 	    case Constraint of
 		[#'Externaltypereference'{type=Tname}] ->
 		    EncFunc = enc_func(Tname),
-		    Imm = [{apply,{local,EncFunc,[]},[{expr,Val}]}],
+		    Imm = [{apply,{local,EncFunc,[]},[Val]}],
 		    asn1ct_imm:per_enc_open_type(Imm, Aligned);
 		[] ->
-		    Imm = [{call,erlang,iolist_to_binary,[{expr,Val}]}],
+		    Imm = [{call,erlang,iolist_to_binary,[Val]}],
 		    asn1ct_imm:per_enc_open_type(Imm, Aligned)
 	    end
     end.
diff --git a/lib/asn1/src/asn1ct_imm.erl b/lib/asn1/src/asn1ct_imm.erl
index 9089fdf983..ab5969e891 100644
--- a/lib/asn1/src/asn1ct_imm.erl
+++ b/lib/asn1/src/asn1ct_imm.erl
@@ -36,7 +36,7 @@
 	 per_enc_small_number/2]).
 -export([per_enc_extension_bit/2,per_enc_extensions/4,per_enc_optional/3]).
 -export([per_enc_sof/5]).
--export([enc_absent/3,enc_append/1,enc_bind_var/1]).
+-export([enc_absent/3,enc_append/1,enc_element/2]).
 -export([enc_cg/2]).
 -export([optimize_alignment/1,optimize_alignment/2,
 	 dec_slim_cg/2,dec_code_gen/2]).
@@ -270,7 +270,7 @@ per_enc_open_type([{'cond',
     ToBin = {erlang,iolist_to_binary},
     Imm ++ per_enc_open_type(Dst, ToBin, Aligned);
 per_enc_open_type([{call,erlang,iolist_to_binary,Args}], Aligned) ->
-    {_,[_,Bin,Len]} = mk_vars('dummy', [bin,len]),
+    {_,[_,Bin,Len]} = mk_vars([], [bin,len]),
     [{call,erlang,iolist_to_binary,Args,Bin},
      {call,erlang,byte_size,[Bin],Len}|per_enc_length(Bin, 8, Len, Aligned)];
 per_enc_open_type(Imm0, Aligned) ->
@@ -321,23 +321,21 @@ per_enc_extensions(Val0, Pos0, NumBits, Aligned) when NumBits > 0 ->
 
 per_enc_optional(Val0, {Pos,DefVals}, _Aligned) when is_integer(Pos),
 						     is_list(DefVals) ->
-    Val1 = lists:concat(["element(",Pos,", ",Val0,")"]),
-    {B,[Val]} = mk_vars(Val1, []),
+    {B,Val} = enc_element(Pos, Val0),
     Zero = {put_bits,0,1,[1]},
     One = {put_bits,1,1,[1]},
     B++[{'cond',
 	 [[{eq,Val,DefVal},Zero] || DefVal <- DefVals] ++ [['_',One]]}];
 per_enc_optional(Val0, {Pos,{call,M,F,A}}, _Aligned) when is_integer(Pos) ->
-    Val1 = lists:concat(["element(",Pos,", ",Val0,")"]),
-    {B,[Val,Tmp]} = mk_vars(Val1, [tmp]),
+    {B,Val} = enc_element(Pos, Val0),
+    {[],[[],Tmp]} = mk_vars([], [tmp]),
     Zero = {put_bits,0,1,[1]},
     One = {put_bits,1,1,[1]},
     B++[{call,M,F,[Val|A],Tmp},
 	{'cond',
 	 [[{eq,Tmp,true},Zero],['_',One]]}];
 per_enc_optional(Val0, Pos, _Aligned) when is_integer(Pos) ->
-    Val1 = lists:concat(["element(",Pos,", ",Val0,")"]),
-    {B,[Val]} = mk_vars(Val1, []),
+    {B,Val} = enc_element(Pos, Val0),
     Zero = {put_bits,0,1,[1]},
     One = {put_bits,1,1,[1]},
     B++[{'cond',[[{eq,Val,asn1_NOVALUE},Zero],
@@ -391,9 +389,9 @@ enc_append([H|T]) ->
     [{block,H}|enc_append(T)];
 enc_append([]) -> [].
 
-enc_bind_var(Val) ->
-    {B,[{var,Var}]} = mk_vars(Val, []),
-    {B,list_to_atom(Var)}.
+enc_element(N, Val0) ->
+    {[],[Val,Dst]} = mk_vars(Val0, [element]),
+    {[{call,erlang,element,[N,Val],Dst}],Dst}.
 
 enc_cg(Imm0, false) ->
     Imm1 = enc_cse(Imm0),
@@ -988,17 +986,13 @@ mk_vars(Input0, Temps) ->
     Curr = asn1ct_name:curr(enc),
     [H|T] = atom_to_list(Curr),
     Base = [H - ($a - $A)|T ++ "@"],
-    if
-	is_atom(Input0) ->
-	    Input = {var,atom_to_list(Input0)},
-	    {[],[Input|mk_vars_1(Base, Temps)]};
-	is_integer(Input0) ->
+    case Input0 of
+	{var,Name} when is_list(Name) ->
 	    {[],[Input0|mk_vars_1(Base, Temps)]};
-	Input0 =:= [] ->
+	[] ->
 	    {[],[Input0|mk_vars_1(Base, Temps)]};
-	true ->
-	    Input = mk_var(Base, input),
-	    {[{assign,Input,Input0}],[Input|mk_vars_1(Base, Temps)]}
+	_ when is_integer(Input0) ->
+	    {[],[Input0|mk_vars_1(Base, Temps)]}
     end.
 
 mk_vars_1(Base, Vars) ->
@@ -1402,16 +1396,16 @@ num_bits([], Sum) -> Sum.
 
 per_enc_open_type_output([{apply,F,A}], Acc) ->
     Dst = output_var(),
-    {Dst,lists:reverse(Acc, [{apply,F,A,{var,atom_to_list(Dst)}}])};
+    {Dst,lists:reverse(Acc, [{apply,F,A,Dst}])};
 per_enc_open_type_output([{call,M,F,A}], Acc) ->
     Dst = output_var(),
-    {Dst,lists:reverse(Acc, [{call,M,F,A,{var,atom_to_list(Dst)}}])};
+    {Dst,lists:reverse(Acc, [{call,M,F,A,Dst}])};
 per_enc_open_type_output([{call_gen,P,K,G,I,As}], Acc) ->
     Dst = output_var(),
-    {Dst,lists:reverse(Acc, [{call_gen,P,K,G,I,As,{var,atom_to_list(Dst)}}])};
+    {Dst,lists:reverse(Acc, [{call_gen,P,K,G,I,As,Dst}])};
 per_enc_open_type_output([{'cond',Cs}], Acc) ->
     Dst = output_var(),
-    {Dst,lists:reverse(Acc, [{'cond',Cs,{var,atom_to_list(Dst)}}])};
+    {Dst,lists:reverse(Acc, [{'cond',Cs,Dst}])};
 per_enc_open_type_output([H|T], Acc) ->
     per_enc_open_type_output(T, [H|Acc]).
 
@@ -1419,7 +1413,7 @@ output_var() ->
     asn1ct_name:new(enc),
     Curr = asn1ct_name:curr(enc),
     [H|T] = atom_to_list(Curr),
-    list_to_atom([H - ($a - $A)|T ++ "@output"]).
+    {var,[H - ($a - $A)|T ++ "@output"]}.
 
 
 %%%
@@ -1599,16 +1593,16 @@ collect_put_bits(Imm) ->
 %%% the same element twice.
 %%%
 
-enc_cse([{assign,{var,V},E}=H|T]) ->
-    [H|enc_cse_1(T, E, V)];
+enc_cse([{call,erlang,element,Args,V}=H|T]) ->
+    [H|enc_cse_1(T, Args, V)];
 enc_cse(Imm) -> Imm.
 
-enc_cse_1([{assign,Dst,E}|T], E, V) ->
-    [{assign,Dst,V}|enc_cse_1(T, E, V)];
-enc_cse_1([{block,Bl}|T], E, V) ->
-    [{block,enc_cse_1(Bl, E, V)}|enc_cse_1(T, E, V)];
-enc_cse_1([H|T], E, V) ->
-    [H|enc_cse_1(T, E, V)];
+enc_cse_1([{call,erlang,element,Args,Dst}|T], Args, V) ->
+    [{set,V,Dst}|enc_cse_1(T, Args, V)];
+enc_cse_1([{block,Bl}|T], Args, V) ->
+    [{block,enc_cse_1(Bl, Args, V)}|enc_cse_1(T, Args, V)];
+enc_cse_1([H|T], Args, V) ->
+    [H|enc_cse_1(T, Args, V)];
 enc_cse_1([], _, _) -> [].