1 files changed, 52 insertions, 15 deletions

diff --git a/lib/compiler/src/v3_codegen.erl b/lib/compiler/src/v3_codegen.erl
index d0c337e3ca..7cfc8d8197 100644
--- a/lib/compiler/src/v3_codegen.erl
+++ b/lib/compiler/src/v3_codegen.erl
@@ -943,27 +943,34 @@ 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 ->
-			{{[Key|HasKsi],GetVsi},Int0};
+			RK = fetch_var(K,Int0),
+			{{HasKsi,GetVsi,[RK|HasVarVsi],GetVarVsi},Int0};
 		    _Other ->
 			Reg1 = put_reg(V, Int0#sr.reg),
 			Int1 = Int0#sr{reg=Reg1},
-			{{HasKsi,[Key,fetch_reg(V, Reg1)|GetVsi]},Int1}
+			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,HasVarVsi,GetVarVsi},Int0};
+		    _Other ->
+			Reg1 = put_reg(V, Int0#sr.reg),
+			Int1 = Int0#sr{reg=Reg1},
+			{{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}.
 
 
@@ -1500,9 +1507,39 @@ 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};
+% 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},
+    {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),
+
+    List = [cg_reg_arg(K,Int0),cg_reg_arg(V,Int0)],
+
+    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),
+
+    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