fast-vs-slow.diff

--- couch_key_tree.no-sink-opt.S	2022-03-21 14:51:30.000000000 -0500
+++ couch_key_tree.opt.S	2022-03-21 14:50:44.000000000 -0500
@@ -26,7 +26,7 @@
 
 {attributes, []}.
 
-{labels, 270}.
+{labels, 269}.
 
 
 {function, multi_merge, 2, 2}.
@@ -36,7 +36,7 @@
   {label,2}.
     {allocate_heap,2,{alloc,[{words,0},{floats,0},{funs,1}]},2}.
     {move,{x,0},{y,1}}.
-    {make_fun3,{f,269},0,0,{y,0},{list,[]}}.
+    {make_fun3,{f,268},0,0,{y,0},{list,[]}}.
     {'%',{var_info,{y,0},[{fun_type,{t_list,any,nil}}]}}.
     {move,{x,1},{x,0}}.
     {line,[{location,"couch_key_tree.erl",51}]}.
@@ -86,24 +86,26 @@
     {get_list,{x,0},{x,3},{x,4}}.
     {test,is_tuple,{f,5},[{x,3}]}.
     {test,test_arity,{f,5},[{x,3},2]}.
-    {get_tuple_element,{x,3},0,{x,5}}.
-    {get_tuple_element,{x,3},1,{x,6}}.
     {test,is_tuple,{f,5},[{x,1}]}.
     {test,test_arity,{f,5},[{x,1},2]}.
-    {get_tuple_element,{x,1},0,{x,0}}.
-    {get_tuple_element,{x,1},1,{x,7}}.
+    {get_tuple_element,{x,3},0,{x,0}}.
+    {get_tuple_element,{x,1},0,{x,5}}.
     {line,[{location,"couch_key_tree.erl",84}]}.
-    {gc_bif,'-',{f,0},8,[{x,5},{x,0}],{x,8}}.
-    {allocate_heap,6,4,9}.
-    {move,{x,0},{y,0}}.
+    {gc_bif,'-',{f,0},6,[{x,0},{x,5}],{x,6}}.
+    {allocate_heap,7,4,7}.
+    {init_yregs,{list,[{y,0}]}}.
     {move,{x,5},{y,1}}.
-    {move,{x,3},{y,2}}.
-    {move,{x,4},{y,3}}.
-    {move,{x,2},{y,4}}.
-    {move,{x,1},{y,5}}.
-    {put_list,{x,6},nil,{x,0}}.
-    {put_list,{x,7},nil,{x,2}}.
-    {move,{x,8},{x,1}}.
+    {move,{x,0},{y,2}}.
+    {move,{x,3},{y,3}}.
+    {move,{x,4},{y,4}}.
+    {move,{x,2},{y,5}}.
+    {move,{x,1},{y,6}}.
+    {get_tuple_element,{x,1},1,{x,0}}.
+    {get_tuple_element,{x,3},1,{x,1}}.
+    {put_list,{x,1},nil,{x,1}}.
+    {put_list,{x,0},nil,{x,2}}.
+    {move,{x,1},{x,0}}.
+    {move,{x,6},{x,1}}.
     {call,3,{f,12}}.
     {'%',
         {var_info,
@@ -116,32 +118,35 @@
                          #{1 => {t_cons,any,any},
                            2 => {t_atom,[internal_node,new_branch,new_leaf]}}},
                      none}}]}}.
+    {move,{x,0},{y,0}}.
     {test,is_tuple,{f,7},[{x,0}]}.
-    {get_tuple_element,{x,0},0,{x,1}}.
-    {get_tuple_element,{x,0},1,{y,5}}.
-    {get_list,{x,1},{y,2},{x,1}}.
-    {test,is_nil,{f,10},[{x,1}]}.
-    {move,{y,0},{x,1}}.
-    {move,{y,1},{x,0}}.
-    {trim,2,4}.
+    {get_tuple_element,{x,0},0,{x,0}}.
+    {get_list,{x,0},{y,6},{x,0}}.
+    {test,is_nil,{f,10},[{x,0}]}.
+    {move,{y,1},{x,1}}.
+    {move,{y,2},{x,0}}.
+    {move,{y,0},{y,3}}.
+    {trim,3,4}.
     {call_ext,2,{extfunc,erlang,min,2}}.
     {test_heap,5,1}.
-    {put_tuple2,{x,0},{list,[{x,0},{y,0}]}}.
+    {put_tuple2,{x,0},{list,[{x,0},{y,3}]}}.
     {put_list,{x,0},{y,2},{x,1}}.
     {move,{y,1},{x,0}}.
+    {move,{y,0},{y,3}}.
     {trim,3,1}.
     {line,[{location,"couch_key_tree.erl",87}]}.
     {call_ext,2,{extfunc,erlang,'++',2}}.
     {test_heap,3,1}.
-    {put_tuple2,{x,0},{list,[{x,0},{y,0}]}}.
+    {get_tuple_element,{y,0},1,{x,1}}.
+    {put_tuple2,{x,0},{list,[{x,0},{x,1}]}}.
     {deallocate,1}.
     return.
   {label,7}.
     {test_heap,2,0}.
-    {put_list,{y,2},{y,4},{x,2}}.
-    {move,{y,5},{x,1}}.
-    {move,{y,3},{x,0}}.
-    {call_last,3,{f,6},6}.
+    {put_list,{y,3},{y,5},{x,2}}.
+    {move,{y,6},{x,1}}.
+    {move,{y,4},{x,0}}.
+    {call_last,3,{f,6},7}.
   {label,8}.
     {test,is_nil,{f,5},[{x,0}]}.
     {test,is_nil,{f,9},[{x,2}]}.
@@ -156,7 +161,7 @@
     return.
   {label,10}.
     {line,[{location,"couch_key_tree.erl",84}]}.
-    {case_end,{x,0}}.
+    {case_end,{y,0}}.
 
 
 {function, merge_at, 3, 12}.
@@ -166,24 +171,21 @@
   {label,12}.
     {'%',{var_info,{x,1},[{type,number}]}}.
     {'%',{var_info,{x,2},[{type,{t_cons,any,any}}]}}.
-    {test,is_ne_exact,{f,20},[{x,0},nil]}.
+    {test,is_ne_exact,{f,19},[{x,0},nil]}.
     {get_list,{x,2},{x,3},{x,4}}.
-    {test,is_tuple,{f,15},[{x,3}]}.
-    {test,test_arity,{f,15},[{x,3},3]}.
-    {get_tuple_element,{x,3},0,{x,5}}.
-    {get_tuple_element,{x,3},1,{x,6}}.
-    {get_tuple_element,{x,3},2,{x,7}}.
-    {test,is_nonempty_list,{f,14},[{x,7}]}.
-    {get_tl,{x,7},{x,8}}.
-    {test,is_nil,{f,15},[{x,8}]}.
-    {test,is_nil,{f,15},[{x,4}]}.
-    {test,is_lt,{f,15},[{integer,0},{x,1}]}.
+    {test,is_tuple,{f,14},[{x,3}]}.
+    {test,test_arity,{f,14},[{x,3},3]}.
+    {get_tuple_element,{x,3},2,{x,5}}.
+    {test,is_nonempty_list,{f,13},[{x,5}]}.
+    {get_tl,{x,5},{x,6}}.
+    {test,is_nil,{f,14},[{x,6}]}.
+    {test,is_nil,{f,14},[{x,4}]}.
+    {test,is_lt,{f,14},[{integer,0},{x,1}]}.
     {line,[{location,"couch_key_tree.erl",107}]}.
-    {gc_bif,'-',{f,0},8,[{x,1},{integer,1}],{x,1}}.
-    {allocate,2,8}.
-    {move,{x,5},{y,0}}.
-    {move,{x,6},{y,1}}.
-    {move,{x,7},{x,2}}.
+    {gc_bif,'-',{f,0},6,[{x,1},{integer,1}],{x,1}}.
+    {allocate,1,6}.
+    {move,{x,3},{y,0}}.
+    {move,{x,5},{x,2}}.
     {call,3,{f,12}}.
     {'%',
         {var_info,
@@ -196,32 +198,30 @@
                          #{1 => {t_cons,any,any},
                            2 => {t_atom,[internal_node,new_branch,new_leaf]}}},
                      none}}]}}.
-    {test,is_tuple,{f,13},[{x,0}]}.
+    {test,is_tuple,{f,21},[{x,0}]}.
     {test_heap,9,1}.
-    {get_tuple_element,{x,0},0,{x,1}}.
+    {get_tuple_element,{y,0},0,{x,1}}.
+    {get_tuple_element,{y,0},1,{x,2}}.
+    {get_tuple_element,{x,0},0,{x,3}}.
     {get_tuple_element,{x,0},1,{x,0}}.
-    {put_tuple2,{x,1},{list,[{y,0},{y,1},{x,1}]}}.
+    {put_tuple2,{x,1},{list,[{x,1},{x,2},{x,3}]}}.
     {put_list,{x,1},nil,{x,1}}.
     {put_tuple2,{x,0},{list,[{x,1},{x,0}]}}.
-    {deallocate,2}.
+    {deallocate,1}.
     return.
   {label,13}.
-    {move,{atom,fail},{x,0}}.
-    {deallocate,2}.
-    return.
+    {test,is_nil,{f,14},[{x,5}]}.
+    {test,is_nil,{f,14},[{x,4}]}.
+    {test,is_ge,{f,19},[{integer,0},{x,1}]}.
   {label,14}.
-    {test,is_nil,{f,15},[{x,7}]}.
-    {test,is_nil,{f,15},[{x,4}]}.
-    {test,is_ge,{f,20},[{integer,0},{x,1}]}.
-  {label,15}.
     {test,is_nonempty_list,{f,11},[{x,0}]}.
     {get_list,{x,0},{x,5},{x,6}}.
-    {test,is_tuple,{f,21},[{x,5}]}.
-    {test,test_arity,{f,21},[{x,5},3]}.
+    {test,is_tuple,{f,20},[{x,5}]}.
+    {test,test_arity,{f,20},[{x,5},3]}.
     {get_tuple_element,{x,5},0,{x,7}}.
     {get_tuple_element,{x,5},1,{x,8}}.
     {get_tuple_element,{x,5},2,{x,9}}.
-    {test,is_lt,{f,18},[{x,1},{integer,0}]}.
+    {test,is_lt,{f,17},[{x,1},{integer,0}]}.
     {line,[{location,"couch_key_tree.erl",118}]}.
     {gc_bif,'+',{f,0},10,[{x,1},{integer,1}],{x,0}}.
     {allocate,6,10}.
@@ -245,7 +245,7 @@
                          #{1 => {t_cons,any,any},
                            2 => {t_atom,[internal_node,new_branch,new_leaf]}}},
                      none}}]}}.
-    {test,is_tuple,{f,16},[{x,0}]}.
+    {test,is_tuple,{f,15},[{x,0}]}.
     {test_heap,9,1}.
     {get_tuple_element,{x,0},0,{x,1}}.
     {get_tuple_element,{x,0},1,{x,0}}.
@@ -254,7 +254,7 @@
     {put_tuple2,{x,0},{list,[{x,1},{x,0}]}}.
     {deallocate,6}.
     return.
-  {label,16}.
+  {label,15}.
     {move,{y,4},{x,2}}.
     {move,{y,5},{x,1}}.
     {move,{y,3},{x,0}}.
@@ -272,7 +272,7 @@
                          #{1 => {t_cons,any,any},
                            2 => {t_atom,[internal_node,new_branch,new_leaf]}}},
                      none}}]}}.
-    {test,is_tuple,{f,17},[{x,0}]}.
+    {test,is_tuple,{f,16},[{x,0}]}.
     {test_heap,5,1}.
     {get_tuple_element,{x,0},0,{x,1}}.
     {get_tuple_element,{x,0},1,{x,0}}.
@@ -280,56 +280,51 @@
     {put_tuple2,{x,0},{list,[{x,1},{x,0}]}}.
     {deallocate,6}.
     return.
-  {label,17}.
+  {label,16}.
     {move,{atom,fail},{x,0}}.
     {deallocate,6}.
     return.
-  {label,18}.
+  {label,17}.
     {test,is_eq_exact,{f,11},[{x,1},{integer,0}]}.
-    {test,is_tuple,{f,21},[{x,3}]}.
-    {test,test_arity,{f,21},[{x,3},3]}.
-    {get_tuple_element,{x,3},0,{x,10}}.
-    {get_tuple_element,{x,3},1,{x,11}}.
-    {get_tuple_element,{x,3},2,{x,3}}.
-    {test,is_nil,{f,21},[{x,4}]}.
-    {test,is_eq_exact,{f,19},[{x,10},{x,7}]}.
-    {allocate,6,12}.
-    {init_yregs,{list,[{y,0},{y,1}]}}.
-    {move,{x,11},{y,2}}.
-    {move,{x,7},{y,3}}.
-    {move,{x,8},{y,4}}.
-    {move,{x,6},{y,5}}.
-    {move,{x,3},{x,1}}.
+    {test,is_tuple,{f,20},[{x,3}]}.
+    {test,test_arity,{f,20},[{x,3},3]}.
+    {test,is_nil,{f,20},[{x,4}]}.
+    {get_tuple_element,{x,3},0,{x,4}}.
+    {test,is_eq_exact,{f,18},[{x,4},{x,7}]}.
+    {allocate,4,10}.
+    {move,{x,3},{y,0}}.
+    {move,{x,7},{y,1}}.
+    {move,{x,8},{y,2}}.
+    {move,{x,6},{y,3}}.
+    {get_tuple_element,{x,3},2,{x,1}}.
     {move,{x,9},{x,0}}.
     {line,[{location,"couch_key_tree.erl",133}]}.
-    {call,2,{f,24}}.
+    {call,2,{f,23}}.
     {'%',
         {var_info,
             {x,0},
             [{type,
                  {t_tuple,2,true,
                      #{2 => {t_atom,[internal_node,new_branch,new_leaf]}}}}]}}.
-    {get_tuple_element,{x,0},0,{y,1}}.
-    {get_tuple_element,{x,0},1,{y,0}}.
-    {move,{y,2},{x,1}}.
-    {move,{y,4},{x,0}}.
-    {init_yregs,{list,[{y,2}]}}.
-    {move,{y,0},{y,4}}.
-    {trim,1,5}.
+    {get_tuple_element,{y,0},1,{x,1}}.
+    {swap,{y,2},{x,0}}.
+    {trim,1,3}.
     {line,[{location,"couch_key_tree.erl",134}]}.
-    {call,2,{f,163}}.
+    {call,2,{f,162}}.
     {test_heap,9,1}.
-    {put_tuple2,{x,0},{list,[{y,2},{x,0},{y,0}]}}.
-    {put_list,{x,0},{y,4},{x,0}}.
-    {put_tuple2,{x,0},{list,[{x,0},{y,3}]}}.
-    {deallocate,5}.
+    {get_tuple_element,{y,1},0,{x,1}}.
+    {get_tuple_element,{y,1},1,{x,2}}.
+    {put_tuple2,{x,0},{list,[{y,0},{x,0},{x,1}]}}.
+    {put_list,{x,0},{y,2},{x,0}}.
+    {put_tuple2,{x,0},{list,[{x,0},{x,2}]}}.
+    {deallocate,3}.
     return.
+  {label,18}.
+    {test,is_lt,{f,20},[{x,4},{x,7}]}.
   {label,19}.
-    {test,is_lt,{f,21},[{x,10},{x,7}]}.
-  {label,20}.
     {move,{atom,fail},{x,0}}.
     return.
-  {label,21}.
+  {label,20}.
     {test,is_eq_exact,{f,11},[{x,1},{integer,0}]}.
     {allocate,1,7}.
     {move,{x,5},{y,0}}.
@@ -348,7 +343,7 @@
                          #{1 => {t_cons,any,any},
                            2 => {t_atom,[internal_node,new_branch,new_leaf]}}},
                      none}}]}}.
-    {test,is_tuple,{f,22},[{x,0}]}.
+    {test,is_tuple,{f,21},[{x,0}]}.
     {test_heap,5,1}.
     {get_tuple_element,{x,0},0,{x,1}}.
     {get_tuple_element,{x,0},1,{x,0}}.
@@ -356,89 +351,86 @@
     {put_tuple2,{x,0},{list,[{x,1},{x,0}]}}.
     {deallocate,1}.
     return.
-  {label,22}.
+  {label,21}.
     {move,{atom,fail},{x,0}}.
     {deallocate,1}.
     return.
 
 
-{function, merge_extend, 2, 24}.
-  {label,23}.
+{function, merge_extend, 2, 23}.
+  {label,22}.
     {line,[{location,"couch_key_tree.erl",147}]}.
     {func_info,{atom,couch_key_tree},{atom,merge_extend},2}.
-  {label,24}.
-    {test,is_nil,{f,25},[{x,0}]}.
-    {test,is_ne_exact,{f,26},[{x,1},nil]}.
+  {label,23}.
+    {test,is_nil,{f,24},[{x,0}]}.
+    {test,is_ne_exact,{f,25},[{x,1},nil]}.
     {test_heap,3,2}.
     {put_tuple2,{x,0},{list,[{x,1},{atom,new_leaf}]}}.
     return.
+  {label,24}.
+    {test,is_nil,{f,26},[{x,1}]}.
   {label,25}.
-    {test,is_nil,{f,27},[{x,1}]}.
-  {label,26}.
     {test_heap,3,1}.
     {put_tuple2,{x,0},{list,[{x,0},{atom,internal_node}]}}.
     return.
-  {label,27}.
-    {test,is_nonempty_list,{f,23},[{x,0}]}.
+  {label,26}.
+    {test,is_nonempty_list,{f,22},[{x,0}]}.
     {get_list,{x,0},{x,2},{x,3}}.
-    {test,is_tuple,{f,29},[{x,2}]}.
-    {test,test_arity,{f,29},[{x,2},3]}.
-    {get_tuple_element,{x,2},0,{x,4}}.
-    {get_tuple_element,{x,2},1,{x,5}}.
-    {get_tuple_element,{x,2},2,{x,6}}.
-    {test,is_nonempty_list,{f,29},[{x,1}]}.
-    {get_list,{x,1},{x,7},{x,8}}.
-    {test,is_tuple,{f,29},[{x,7}]}.
-    {test,test_arity,{f,29},[{x,7},3]}.
-    {get_tuple_element,{x,7},0,{x,9}}.
-    {get_tuple_element,{x,7},1,{x,10}}.
-    {get_tuple_element,{x,7},2,{x,11}}.
-    {test,is_nil,{f,29},[{x,8}]}.
-    {test,is_eq_exact,{f,28},[{x,9},{x,4}]}.
-    {allocate,6,12}.
-    {init_yregs,{list,[{y,0},{y,1}]}}.
-    {move,{x,10},{y,2}}.
-    {move,{x,4},{y,3}}.
-    {move,{x,5},{y,4}}.
-    {move,{x,3},{y,5}}.
-    {move,{x,11},{x,1}}.
-    {move,{x,6},{x,0}}.
+    {test,is_tuple,{f,28},[{x,2}]}.
+    {test,test_arity,{f,28},[{x,2},3]}.
+    {test,is_nonempty_list,{f,28},[{x,1}]}.
+    {get_list,{x,1},{x,4},{x,5}}.
+    {test,is_tuple,{f,28},[{x,4}]}.
+    {test,test_arity,{f,28},[{x,4},3]}.
+    {get_tuple_element,{x,4},1,{x,6}}.
+    {test,is_nil,{f,28},[{x,5}]}.
+    {get_tuple_element,{x,4},0,{x,5}}.
+    {get_tuple_element,{x,2},0,{x,7}}.
+    {test,is_eq_exact,{f,27},[{x,5},{x,7}]}.
+    {allocate,4,8}.
+    {move,{x,6},{y,0}}.
+    {move,{x,7},{y,1}}.
+    {move,{x,2},{y,2}}.
+    {move,{x,3},{y,3}}.
+    {get_tuple_element,{x,4},2,{x,1}}.
+    {get_tuple_element,{x,2},2,{x,0}}.
     {line,[{location,"couch_key_tree.erl",161}]}.
-    {call,2,{f,24}}.
+    {call,2,{f,23}}.
     {'%',
         {var_info,
             {x,0},
             [{type,
                  {t_tuple,2,true,
                      #{2 => {t_atom,[internal_node,new_branch,new_leaf]}}}}]}}.
-    {get_tuple_element,{x,0},0,{y,1}}.
-    {get_tuple_element,{x,0},1,{y,0}}.
-    {move,{y,2},{x,1}}.
-    {move,{y,4},{x,0}}.
-    {init_yregs,{list,[{y,2}]}}.
-    {move,{y,0},{y,4}}.
-    {trim,1,5}.
+    {get_tuple_element,{y,2},1,{x,1}}.
+    {move,{x,0},{y,2}}.
+    {move,{y,0},{x,2}}.
+    {move,{x,1},{x,0}}.
+    {move,{x,2},{x,1}}.
+    {trim,1,3}.
     {line,[{location,"couch_key_tree.erl",162}]}.
-    {call,2,{f,163}}.
+    {call,2,{f,162}}.
     {test_heap,9,1}.
-    {put_tuple2,{x,0},{list,[{y,2},{x,0},{y,0}]}}.
-    {put_list,{x,0},{y,4},{x,0}}.
-    {put_tuple2,{x,0},{list,[{x,0},{y,3}]}}.
-    {deallocate,5}.
+    {get_tuple_element,{y,1},0,{x,1}}.
+    {get_tuple_element,{y,1},1,{x,2}}.
+    {put_tuple2,{x,0},{list,[{y,0},{x,0},{x,1}]}}.
+    {put_list,{x,0},{y,2},{x,0}}.
+    {put_tuple2,{x,0},{list,[{x,0},{x,2}]}}.
+    {deallocate,3}.
     return.
-  {label,28}.
-    {test,is_lt,{f,29},[{x,9},{x,4}]}.
-    {test_heap,5,8}.
-    {put_list,{x,7},{x,0},{x,0}}.
+  {label,27}.
+    {test,is_lt,{f,28},[{x,5},{x,7}]}.
+    {test_heap,5,5}.
+    {put_list,{x,4},{x,0},{x,0}}.
     {put_tuple2,{x,0},{list,[{x,0},{atom,new_branch}]}}.
     return.
-  {label,29}.
+  {label,28}.
     {allocate,2,4}.
     {move,{x,2},{y,0}}.
     {move,{x,3},{y,1}}.
     {move,{x,3},{x,0}}.
     {line,[{location,"couch_key_tree.erl",173}]}.
-    {call,2,{f,24}}.
+    {call,2,{f,23}}.
     {'%',
         {var_info,
             {x,0},
@@ -446,17 +438,17 @@
                  {t_tuple,2,true,
                      #{2 => {t_atom,[internal_node,new_branch,new_leaf]}}}}]}}.
     {get_tuple_element,{x,0},0,{x,1}}.
-    {get_tuple_element,{x,0},1,{x,0}}.
     {line,[{location,"couch_key_tree.erl",175}]}.
     {gc_bif,length,{f,0},2,[{x,1}],{x,2}}.
     {gc_bif,length,{f,0},3,[{y,1}],{x,3}}.
-    {test,is_eq_exact,{f,30},[{x,2},{x,3}]}.
+    {test,is_eq_exact,{f,29},[{x,2},{x,3}]}.
     {test_heap,5,2}.
+    {get_tuple_element,{x,0},1,{x,0}}.
     {put_list,{y,0},{x,1},{x,1}}.
     {put_tuple2,{x,0},{list,[{x,1},{x,0}]}}.
     {deallocate,2}.
     return.
-  {label,30}.
+  {label,29}.
     {test_heap,5,2}.
     {put_list,{y,0},{x,1},{x,0}}.
     {put_tuple2,{x,0},{list,[{x,0},{atom,new_branch}]}}.
@@ -464,37 +456,36 @@
     return.
 
 
-{function, find_missing, 2, 32}.
-  {label,31}.
+{function, find_missing, 2, 31}.
+  {label,30}.
     {line,[{location,"couch_key_tree.erl",181}]}.
     {func_info,{atom,couch_key_tree},{atom,find_missing},2}.
-  {label,32}.
-    {test,is_nil,{f,33},[{x,1}]}.
+  {label,31}.
+    {test,is_nil,{f,32},[{x,1}]}.
     {move,nil,{x,0}}.
     return.
-  {label,33}.
-    {test,is_nonempty_list,{f,34},[{x,0}]}.
+  {label,32}.
+    {test,is_nonempty_list,{f,33},[{x,0}]}.
     {get_list,{x,0},{x,2},{x,3}}.
-    {test,is_tuple,{f,31},[{x,2}]}.
-    {test,test_arity,{f,31},[{x,2},2]}.
-    {get_tuple_element,{x,2},0,{x,4}}.
-    {get_tuple_element,{x,2},1,{x,2}}.
-    {test,is_tuple,{f,31},[{x,2}]}.
-    {test,test_arity,{f,31},[{x,2},3]}.
+    {test,is_tuple,{f,30},[{x,2}]}.
+    {test,test_arity,{f,30},[{x,2},2]}.
+    {get_tuple_element,{x,2},1,{x,4}}.
+    {test,is_tuple,{f,30},[{x,4}]}.
+    {test,test_arity,{f,30},[{x,4},3]}.
     {allocate,4,5}.
-    {move,{x,4},{y,0}}.
-    {move,{x,2},{y,1}}.
+    {move,{x,4},{y,1}}.
     {move,{x,3},{y,2}}.
     {move,{x,1},{y,3}}.
+    {get_tuple_element,{x,2},0,{y,0}}.
     {move,{x,1},{x,0}}.
-    {move,{x,4},{x,1}}.
+    {move,{y,0},{x,1}}.
     {line,[{location,"couch_key_tree.erl",186}]}.
-    {call,2,{f,264}}.
+    {call,2,{f,263}}.
     {'%',{var_info,{x,0},[{type,{t_list,{t_tuple,2,true,#{}},nil}}]}}.
     {swap,{y,3},{x,0}}.
     {move,{y,0},{x,1}}.
     {line,[{location,"couch_key_tree.erl",187}]}.
-    {call,2,{f,259}}.
+    {call,2,{f,258}}.
     {'%',{var_info,{x,0},[{type,{t_list,{t_tuple,2,true,#{}},nil}}]}}.
     {test_heap,2,1}.
     {put_list,{y,1},nil,{x,1}}.
@@ -504,7 +495,7 @@
     {trim,2,2}.
     {move,{x,3},{x,0}}.
     {line,[{location,"couch_key_tree.erl",188}]}.
-    {call,3,{f,36}}.
+    {call,3,{f,35}}.
     {'%',{var_info,{x,0},[{type,{t_list,{t_tuple,2,true,#{}},nil}}]}}.
     {move,{x,0},{x,1}}.
     {move,{y,1},{x,0}}.
@@ -513,45 +504,46 @@
     {call_ext,2,{extfunc,erlang,'++',2}}.
     {move,{x,0},{x,1}}.
     {move,{y,0},{x,0}}.
-    {call_last,2,{f,32},2}.
-  {label,34}.
-    {test,is_nil,{f,31},[{x,0}]}.
+    {call_last,2,{f,31},2}.
+  {label,33}.
+    {test,is_nil,{f,30},[{x,0}]}.
     {move,{x,1},{x,0}}.
     return.
 
 
-{function, find_missing_simple, 3, 36}.
-  {label,35}.
+{function, find_missing_simple, 3, 35}.
+  {label,34}.
     {line,[{location,"couch_key_tree.erl",191}]}.
     {func_info,{atom,couch_key_tree},{atom,find_missing_simple},3}.
-  {label,36}.
+  {label,35}.
     {'%',{var_info,{x,2},[{type,{t_list,{t_tuple,2,true,#{}},nil}}]}}.
-    {test,is_nil,{f,37},[{x,2}]}.
+    {test,is_nil,{f,36},[{x,2}]}.
     {move,nil,{x,0}}.
     return.
-  {label,37}.
-    {test,is_nonempty_list,{f,38},[{x,1}]}.
+  {label,36}.
+    {test,is_nonempty_list,{f,37},[{x,1}]}.
     {get_list,{x,1},{x,3},{x,4}}.
-    {test,is_tuple,{f,35},[{x,3}]}.
-    {test,test_arity,{f,35},[{x,3},3]}.
+    {test,is_tuple,{f,34},[{x,3}]}.
+    {test,test_arity,{f,34},[{x,3},3]}.
     {allocate,5,5}.
+    {move,{x,3},{y,1}}.
     {move,{x,4},{y,2}}.
     {move,{x,2},{y,3}}.
     {move,{x,0},{y,4}}.
-    {get_tuple_element,{x,3},0,{y,1}}.
     {get_tuple_element,{x,3},2,{y,0}}.
     {move,{x,0},{x,1}}.
     {move,{x,2},{x,0}}.
     {line,[{location,"couch_key_tree.erl",196}]}.
-    {call,2,{f,255}}.
+    {call,2,{f,254}}.
     {'%',{var_info,{x,0},[{type,{t_list,{t_tuple,2,true,#{}},nil}}]}}.
     {swap,{y,3},{x,0}}.
     {move,{y,4},{x,1}}.
     {line,[{location,"couch_key_tree.erl",197}]}.
-    {call,2,{f,251}}.
+    {call,2,{f,250}}.
     {'%',{var_info,{x,0},[{type,{t_list,{t_tuple,2,true,#{}},nil}}]}}.
     {test_heap,5,1}.
-    {put_tuple2,{x,1},{list,[{y,4},{y,1}]}}.
+    {get_tuple_element,{y,1},0,{x,1}}.
+    {put_tuple2,{x,1},{list,[{y,4},{x,1}]}}.
     {put_list,{x,1},nil,{x,1}}.
     {swap,{y,3},{x,0}}.
     {init_yregs,{list,[{y,1}]}}.
@@ -563,7 +555,7 @@
     {move,{x,1},{x,0}}.
     {move,{y,0},{x,1}}.
     {trim,2,3}.
-    {call,3,{f,36}}.
+    {call,3,{f,35}}.
     {'%',{var_info,{x,0},[{type,{t_list,{t_tuple,2,true,#{}},nil}}]}}.
     {move,{y,0},{x,1}}.
     {move,{x,0},{x,2}}.
@@ -571,22 +563,22 @@
     {move,{y,1},{y,2}}.
     {trim,2,1}.
     {line,[{location,"couch_key_tree.erl",201}]}.
-    {call,3,{f,36}}.
+    {call,3,{f,35}}.
     {'%',{var_info,{x,0},[{type,{t_list,{t_tuple,2,true,#{}},nil}}]}}.
     {move,{x,0},{x,1}}.
     {move,{y,0},{x,0}}.
     {call_ext_last,2,{extfunc,erlang,'++',2},1}.
-  {label,38}.
-    {test,is_nil,{f,35},[{x,1}]}.
+  {label,37}.
+    {test,is_nil,{f,34},[{x,1}]}.
     {move,{x,2},{x,0}}.
     return.
 
 
-{function, filter_leafs, 4, 40}.
-  {label,39}.
+{function, filter_leafs, 4, 39}.
+  {label,38}.
     {line,[{location,"couch_key_tree.erl",203}]}.
     {func_info,{atom,couch_key_tree},{atom,filter_leafs},4}.
-  {label,40}.
+  {label,39}.
     {'%',
         {var_info,
             {x,0},
@@ -604,49 +596,49 @@
                          #{2 => {t_cons,{t_tuple,2,true,#{}},nil}}},
                      nil}}]}}.
     {'%',{var_info,{x,3},[{type,{t_list,{t_tuple,2,true,#{}},nil}}]}}.
-    {test,is_nonempty_list,{f,42},[{x,0}]}.
+    {test,is_nonempty_list,{f,41},[{x,0}]}.
     {allocate_heap,7,3,4}.
     {move,{x,3},{y,4}}.
     {move,{x,2},{y,5}}.
     {move,{x,1},{y,6}}.
     {get_list,{x,0},{y,3},{y,2}}.
-    {get_tuple_element,{y,3},0,{y,1}}.
     {get_tuple_element,{y,3},1,{x,0}}.
     {get_hd,{x,0},{x,0}}.
+    {get_tuple_element,{y,3},0,{y,1}}.
     {get_tuple_element,{x,0},0,{y,0}}.
     {put_tuple2,{x,0},{list,[{y,1},{y,0}]}}.
     {line,[{location,"couch_key_tree.erl",206}]}.
     {call_ext,2,{extfunc,lists,delete,2}}.
-    {test,is_eq,{f,41},[{x,0},{y,6}]}.
+    {test,is_eq,{f,40},[{x,0},{y,6}]}.
     {test_heap,2,0}.
     {put_list,{y,3},{y,5},{x,2}}.
     {move,{y,4},{x,3}}.
     {move,{y,6},{x,1}}.
     {move,{y,2},{x,0}}.
-    {call_last,4,{f,40},7}.
-  {label,41}.
+    {call_last,4,{f,39},7}.
+  {label,40}.
     {test_heap,5,1}.
     {put_tuple2,{x,1},{list,[{y,1},{y,0}]}}.
     {put_list,{x,1},{y,4},{x,3}}.
     {move,{x,0},{x,1}}.
     {move,{y,5},{x,2}}.
     {move,{y,2},{x,0}}.
-    {call_last,4,{f,40},7}.
-  {label,42}.
+    {call_last,4,{f,39},7}.
+  {label,41}.
     {test_heap,3,4}.
     {put_tuple2,{x,0},{list,[{x,2},{x,3}]}}.
     return.
 
 
-{function, remove_leafs, 2, 44}.
-  {label,43}.
+{function, remove_leafs, 2, 43}.
+  {label,42}.
     {line,[{location,"couch_key_tree.erl",217}]}.
     {func_info,{atom,couch_key_tree},{atom,remove_leafs},2}.
-  {label,44}.
+  {label,43}.
     {allocate,1,2}.
     {move,{x,1},{y,0}}.
     {line,[{location,"couch_key_tree.erl",219}]}.
-    {call,1,{f,75}}.
+    {call,1,{f,74}}.
     {'%',
         {var_info,
             {x,0},
@@ -660,7 +652,7 @@
     {move,{y,0},{x,1}}.
     {init_yregs,{list,[{y,0}]}}.
     {line,[{location,"couch_key_tree.erl",222}]}.
-    {call,4,{f,40}}.
+    {call,4,{f,39}}.
     {'%',
         {var_info,
             {x,0},
@@ -676,7 +668,7 @@
     {get_tuple_element,{x,0},1,{y,0}}.
     {move,{x,1},{x,0}}.
     {line,[{location,"couch_key_tree.erl",225}]}.
-    {call,1,{f,248}}.
+    {call,1,{f,247}}.
     {'%',
         {var_info,
             {x,0},
@@ -689,7 +681,7 @@
     {line,[{location,"couch_key_tree.erl",224}]}.
     {call_ext,1,{extfunc,lists,sort,1}}.
     {test_heap,{alloc,[{words,0},{floats,0},{funs,1}]},1}.
-    {make_fun3,{f,243},0,0,{x,1},{list,[]}}.
+    {make_fun3,{f,242},0,0,{x,1},{list,[]}}.
     {'%',{var_info,{x,1},[{fun_type,{t_list,any,nil}}]}}.
     {move,{x,0},{x,2}}.
     {move,{x,1},{x,0}}.
@@ -702,20 +694,20 @@
     return.
 
 
-{function, get_key_leafs, 2, 46}.
-  {label,45}.
+{function, get_key_leafs, 2, 45}.
+  {label,44}.
     {line,[{location,"couch_key_tree.erl",245}]}.
     {func_info,{atom,couch_key_tree},{atom,get_key_leafs},2}.
-  {label,46}.
+  {label,45}.
     {move,nil,{x,2}}.
-    {call_only,3,{f,48}}.
+    {call_only,3,{f,47}}.
 
 
-{function, get_key_leafs, 3, 48}.
-  {label,47}.
+{function, get_key_leafs, 3, 47}.
+  {label,46}.
     {line,[{location,"couch_key_tree.erl",248}]}.
     {func_info,{atom,couch_key_tree},{atom,get_key_leafs},3}.
-  {label,48}.
+  {label,47}.
     {'%',
         {var_info,
             {x,2},
@@ -724,26 +716,26 @@
                      {t_tuple,2,true,
                          #{2 => {t_tuple,2,true,#{2 => {t_cons,any,any}}}}},
                      nil}}]}}.
-    {test,is_nil,{f,49},[{x,1}]}.
+    {test,is_nil,{f,48},[{x,1}]}.
     {test_heap,3,3}.
     {put_tuple2,{x,0},{list,[{x,2},nil]}}.
     return.
-  {label,49}.
-    {test,is_nonempty_list,{f,50},[{x,0}]}.
+  {label,48}.
+    {test,is_nonempty_list,{f,49},[{x,0}]}.
     {get_list,{x,0},{x,3},{x,4}}.
-    {test,is_tuple,{f,47},[{x,3}]}.
-    {test,test_arity,{f,47},[{x,3},2]}.
-    {allocate_heap,3,2,5}.
-    {init_yregs,{list,[{y,0}]}}.
-    {move,{x,4},{y,1}}.
-    {move,{x,2},{y,2}}.
-    {get_tuple_element,{x,3},0,{x,0}}.
-    {get_tuple_element,{x,3},1,{x,2}}.
-    {put_list,{x,2},nil,{x,2}}.
+    {test,is_tuple,{f,46},[{x,3}]}.
+    {test,test_arity,{f,46},[{x,3},2]}.
+    {allocate_heap,2,2,5}.
+    {move,{x,4},{y,0}}.
+    {move,{x,2},{y,1}}.
+    {get_tuple_element,{x,3},1,{x,0}}.
+    {put_list,{x,0},nil,{x,0}}.
+    {get_tuple_element,{x,3},0,{x,2}}.
     {move,nil,{x,3}}.
     {swap,{x,1},{x,2}}.
+    {swap,{x,0},{x,1}}.
     {line,[{location,"couch_key_tree.erl",253}]}.
-    {call,4,{f,52}}.
+    {call,4,{f,51}}.
     {'%',
      {var_info,
       {x,0},
@@ -755,61 +747,61 @@
               #{2 => {t_tuple,2,true,#{2 => {t_cons,any,any}}}}},
              nil}}}}]}}.
     {get_tuple_element,{x,0},0,{x,1}}.
-    {get_tuple_element,{x,0},1,{y,0}}.
+    {move,{y,1},{x,2}}.
+    {move,{x,0},{y,1}}.
     {move,{x,1},{x,0}}.
-    {move,{y,2},{x,1}}.
-    {init_yregs,{list,[{y,2}]}}.
+    {move,{x,2},{x,1}}.
     {line,[{location,"couch_key_tree.erl",254}]}.
     {call_ext,2,{extfunc,erlang,'++',2}}.
-    {move,{y,0},{x,1}}.
+    {get_tuple_element,{y,1},1,{x,1}}.
     {move,{x,0},{x,2}}.
-    {move,{y,1},{x,0}}.
-    {call_last,3,{f,48},3}.
-  {label,50}.
-    {test,is_nil,{f,47},[{x,0}]}.
+    {move,{y,0},{x,0}}.
+    {call_last,3,{f,47},2}.
+  {label,49}.
+    {test,is_nil,{f,46},[{x,0}]}.
     {test_heap,3,3}.
     {put_tuple2,{x,0},{list,[{x,2},{x,1}]}}.
     return.
 
 
-{function, get_key_leafs_simple, 4, 52}.
-  {label,51}.
+{function, get_key_leafs_simple, 4, 51}.
+  {label,50}.
     {line,[{location,"couch_key_tree.erl",256}]}.
     {func_info,{atom,couch_key_tree},{atom,get_key_leafs_simple},4}.
-  {label,52}.
+  {label,51}.
     {'%',{var_info,{x,3},[{type,{t_list,any,nil}}]}}.
-    {test,is_nil,{f,53},[{x,2}]}.
+    {test,is_nil,{f,52},[{x,2}]}.
     {move,{literal,{[],[]}},{x,0}}.
     return.
-  {label,53}.
-    {test,is_nonempty_list,{f,55},[{x,1}]}.
+  {label,52}.
+    {test,is_nonempty_list,{f,54},[{x,1}]}.
     {get_list,{x,1},{x,4},{x,5}}.
-    {test,is_tuple,{f,51},[{x,4}]}.
-    {test,test_arity,{f,51},[{x,4},3]}.
-    {allocate_heap,7,3,6}.
-    {move,{x,4},{y,2}}.
-    {move,{x,5},{y,3}}.
-    {move,{x,3},{y,4}}.
-    {move,{x,2},{y,5}}.
-    {move,{x,0},{y,6}}.
-    {get_tuple_element,{x,4},0,{y,1}}.
-    {get_tuple_element,{x,4},2,{y,0}}.
-    {put_tuple2,{x,0},{list,[{x,0},{y,1}]}}.
+    {test,is_tuple,{f,50},[{x,4}]}.
+    {test,test_arity,{f,50},[{x,4},3]}.
+    {allocate_heap,6,3,6}.
+    {move,{x,4},{y,1}}.
+    {move,{x,5},{y,2}}.
+    {move,{x,3},{y,3}}.
+    {move,{x,2},{y,4}}.
+    {move,{x,0},{y,5}}.
+    {get_tuple_element,{x,4},0,{y,0}}.
+    {put_tuple2,{x,0},{list,[{x,0},{y,0}]}}.
     {move,{x,2},{x,1}}.
     {line,[{location,"couch_key_tree.erl",261}]}.
     {call_ext,2,{extfunc,lists,delete,2}}.
-    {test,is_eq_exact,{f,54},[{x,0},{y,5}]}.
+    {test,is_eq_exact,{f,53},[{x,0},{y,4}]}.
     {test_heap,2,0}.
-    {put_list,{y,1},{y,4},{x,0}}.
+    {put_list,{y,0},{y,3},{x,0}}.
     {line,[{location,"couch_key_tree.erl",265}]}.
-    {gc_bif,'+',{f,0},1,[{y,6},{integer,1}],{x,1}}.
-    {move,{y,5},{x,2}}.
+    {gc_bif,'+',{f,0},1,[{y,5},{integer,1}],{x,1}}.
+    {get_tuple_element,{y,1},2,{x,2}}.
     {move,{x,0},{x,3}}.
     {move,{x,1},{x,0}}.
-    {move,{y,0},{x,1}}.
-    {init_yregs,{list,[{y,5}]}}.
-    {trim,3,4}.
-    {call,4,{f,52}}.
+    {move,{x,2},{x,1}}.
+    {move,{y,4},{x,2}}.
+    {init_yregs,{list,[{y,4}]}}.
+    {trim,2,4}.
+    {call,4,{f,51}}.
     {'%',
      {var_info,
       {x,0},
@@ -828,7 +820,7 @@
     {init_yregs,{list,[{y,3}]}}.
     {trim,2,2}.
     {line,[{location,"couch_key_tree.erl",266}]}.
-    {call,4,{f,52}}.
+    {call,4,{f,51}}.
     {'%',
      {var_info,
       {x,0},
@@ -840,25 +832,26 @@
               #{2 => {t_tuple,2,true,#{2 => {t_cons,any,any}}}}},
              nil}}}}]}}.
     {get_tuple_element,{x,0},0,{x,1}}.
-    {get_tuple_element,{x,0},1,{y,1}}.
+    {move,{x,0},{y,1}}.
     {move,{y,0},{x,0}}.
     {trim,1,1}.
     {line,[{location,"couch_key_tree.erl",267}]}.
     {call_ext,2,{extfunc,erlang,'++',2}}.
     {test_heap,3,1}.
-    {put_tuple2,{x,0},{list,[{x,0},{y,0}]}}.
+    {get_tuple_element,{y,0},1,{x,1}}.
+    {put_tuple2,{x,0},{list,[{x,0},{x,1}]}}.
     {deallocate,1}.
     return.
-  {label,54}.
+  {label,53}.
     {test_heap,2,1}.
-    {put_list,{y,2},nil,{x,1}}.
+    {put_list,{y,1},nil,{x,1}}.
     {move,{x,0},{x,2}}.
-    {move,{y,4},{x,3}}.
-    {init_yregs,{list,[{y,5}]}}.
-    {trim,3,4}.
+    {move,{y,3},{x,3}}.
+    {init_yregs,{list,[{y,4}]}}.
+    {trim,2,4}.
     {move,{y,3},{x,0}}.
     {line,[{location,"couch_key_tree.erl",273}]}.
-    {call,4,{f,57}}.
+    {call,4,{f,56}}.
     {'%',
      {var_info,
       {x,0},
@@ -877,7 +870,7 @@
     {init_yregs,{list,[{y,3}]}}.
     {trim,2,2}.
     {line,[{location,"couch_key_tree.erl",274}]}.
-    {call,4,{f,52}}.
+    {call,4,{f,51}}.
     {'%',
      {var_info,
       {x,0},
@@ -889,36 +882,37 @@
               #{2 => {t_tuple,2,true,#{2 => {t_cons,any,any}}}}},
              nil}}}}]}}.
     {get_tuple_element,{x,0},0,{x,1}}.
-    {get_tuple_element,{x,0},1,{y,1}}.
+    {move,{x,0},{y,1}}.
     {move,{y,0},{x,0}}.
     {trim,1,1}.
     {line,[{location,"couch_key_tree.erl",275}]}.
     {call_ext,2,{extfunc,erlang,'++',2}}.
     {test_heap,3,1}.
-    {put_tuple2,{x,0},{list,[{x,0},{y,0}]}}.
+    {get_tuple_element,{y,0},1,{x,1}}.
+    {put_tuple2,{x,0},{list,[{x,0},{x,1}]}}.
     {deallocate,1}.
     return.
-  {label,55}.
-    {test,is_nil,{f,51},[{x,1}]}.
+  {label,54}.
+    {test,is_nil,{f,50},[{x,1}]}.
     {test_heap,3,3}.
     {put_tuple2,{x,0},{list,[nil,{x,2}]}}.
     return.
 
 
-{function, get_key_leafs_simple2, 4, 57}.
-  {label,56}.
+{function, get_key_leafs_simple2, 4, 56}.
+  {label,55}.
     {line,[{location,"couch_key_tree.erl",278}]}.
     {func_info,{atom,couch_key_tree},{atom,get_key_leafs_simple2},4}.
-  {label,57}.
+  {label,56}.
     {'%',{var_info,{x,3},[{type,{t_list,any,nil}}]}}.
-    {test,is_nonempty_list,{f,59},[{x,1}]}.
+    {test,is_nonempty_list,{f,58},[{x,1}]}.
     {get_list,{x,1},{x,4},{x,5}}.
-    {test,is_tuple,{f,56},[{x,4}]}.
-    {test,test_arity,{f,56},[{x,4},3]}.
+    {test,is_tuple,{f,55},[{x,4}]}.
+    {test,test_arity,{f,55},[{x,4},3]}.
     {get_tuple_element,{x,4},0,{x,1}}.
     {get_tuple_element,{x,4},1,{x,6}}.
     {get_tuple_element,{x,4},2,{x,4}}.
-    {test,is_nil,{f,58},[{x,4}]}.
+    {test,is_nil,{f,57},[{x,4}]}.
     {allocate_heap,5,3,7}.
     {move,{x,1},{y,0}}.
     {move,{x,6},{y,1}}.
@@ -936,7 +930,7 @@
     {trim,1,4}.
     {move,{y,3},{x,0}}.
     {line,[{location,"couch_key_tree.erl",286}]}.
-    {call,4,{f,57}}.
+    {call,4,{f,56}}.
     {'%',
      {var_info,
       {x,0},
@@ -957,7 +951,7 @@
     {put_tuple2,{x,0},{list,[{x,1},{x,0}]}}.
     {deallocate,4}.
     return.
-  {label,58}.
+  {label,57}.
     {allocate_heap,5,3,6}.
     {move,{x,1},{y,0}}.
     {move,{x,4},{y,1}}.
@@ -977,7 +971,7 @@
     {swap,{x,0},{x,2}}.
     {init_yregs,{list,[{y,1}]}}.
     {trim,1,4}.
-    {call,4,{f,57}}.
+    {call,4,{f,56}}.
     {'%',
      {var_info,
       {x,0},
@@ -995,7 +989,7 @@
     {move,{y,3},{x,0}}.
     {init_yregs,{list,[{y,1},{y,2},{y,3}]}}.
     {line,[{location,"couch_key_tree.erl",294}]}.
-    {call,4,{f,57}}.
+    {call,4,{f,56}}.
     {'%',
      {var_info,
       {x,0},
@@ -1007,31 +1001,32 @@
               #{2 => {t_tuple,2,true,#{2 => {t_cons,any,any}}}}},
              nil}}}}]}}.
     {get_tuple_element,{x,0},0,{x,1}}.
-    {get_tuple_element,{x,0},1,{y,3}}.
+    {move,{x,0},{y,3}}.
     {move,{y,0},{x,0}}.
     {trim,3,1}.
     {line,[{location,"couch_key_tree.erl",295}]}.
     {call_ext,2,{extfunc,erlang,'++',2}}.
     {test_heap,3,1}.
-    {put_tuple2,{x,0},{list,[{x,0},{y,0}]}}.
+    {get_tuple_element,{y,0},1,{x,1}}.
+    {put_tuple2,{x,0},{list,[{x,0},{x,1}]}}.
     {deallocate,1}.
     return.
-  {label,59}.
-    {test,is_nil,{f,56},[{x,1}]}.
+  {label,58}.
+    {test,is_nil,{f,55},[{x,1}]}.
     {test_heap,3,3}.
     {put_tuple2,{x,0},{list,[nil,{x,2}]}}.
     return.
 
 
-{function, get, 2, 61}.
-  {label,60}.
+{function, get, 2, 60}.
+  {label,59}.
     {line,[{location,"couch_key_tree.erl",297}]}.
     {func_info,{atom,couch_key_tree},{atom,get},2}.
-  {label,61}.
+  {label,60}.
     {allocate,1,2}.
     {init_yregs,{list,[{y,0}]}}.
     {line,[{location,"couch_key_tree.erl",298}]}.
-    {call,2,{f,63}}.
+    {call,2,{f,62}}.
     {'%',
         {var_info,
             {x,0},
@@ -1046,7 +1041,7 @@
     {get_tuple_element,{x,0},1,{y,0}}.
     {move,{x,1},{x,0}}.
     {line,[{location,"couch_key_tree.erl",301}]}.
-    {call,1,{f,235}}.
+    {call,1,{f,234}}.
     {'%',
         {var_info,
             {x,0},
@@ -1061,20 +1056,20 @@
     return.
 
 
-{function, get_full_key_paths, 2, 63}.
-  {label,62}.
+{function, get_full_key_paths, 2, 62}.
+  {label,61}.
     {line,[{location,"couch_key_tree.erl",305}]}.
     {func_info,{atom,couch_key_tree},{atom,get_full_key_paths},2}.
-  {label,63}.
+  {label,62}.
     {move,nil,{x,2}}.
-    {call_only,3,{f,65}}.
+    {call_only,3,{f,64}}.
 
 
-{function, get_full_key_paths, 3, 65}.
-  {label,64}.
+{function, get_full_key_paths, 3, 64}.
+  {label,63}.
     {line,[{location,"couch_key_tree.erl",308}]}.
     {func_info,{atom,couch_key_tree},{atom,get_full_key_paths},3}.
-  {label,65}.
+  {label,64}.
     {'%',
         {var_info,
             {x,2},
@@ -1083,26 +1078,26 @@
                      {t_tuple,2,true,
                          #{2 => {t_cons,{t_tuple,0,false,#{}},nil}}},
                      nil}}]}}.
-    {test,is_nil,{f,66},[{x,1}]}.
+    {test,is_nil,{f,65},[{x,1}]}.
     {test_heap,3,3}.
     {put_tuple2,{x,0},{list,[{x,2},nil]}}.
     return.
-  {label,66}.
-    {test,is_nonempty_list,{f,67},[{x,0}]}.
+  {label,65}.
+    {test,is_nonempty_list,{f,66},[{x,0}]}.
     {get_list,{x,0},{x,3},{x,4}}.
-    {test,is_tuple,{f,64},[{x,3}]}.
-    {test,test_arity,{f,64},[{x,3},2]}.
-    {allocate_heap,3,2,5}.
-    {init_yregs,{list,[{y,0}]}}.
-    {move,{x,4},{y,1}}.
-    {move,{x,2},{y,2}}.
-    {get_tuple_element,{x,3},0,{x,0}}.
-    {get_tuple_element,{x,3},1,{x,2}}.
-    {put_list,{x,2},nil,{x,2}}.
-    {move,nil,{x,3}}.
-    {swap,{x,1},{x,2}}.
+    {test,is_tuple,{f,63},[{x,3}]}.
+    {test,test_arity,{f,63},[{x,3},2]}.
+    {allocate_heap,2,2,5}.
+    {move,{x,4},{y,0}}.
+    {move,{x,2},{y,1}}.
+    {get_tuple_element,{x,3},1,{x,0}}.
+    {put_list,{x,0},nil,{x,0}}.
+    {get_tuple_element,{x,3},0,{x,2}}.
+    {move,nil,{x,3}}.
+    {swap,{x,1},{x,2}}.
+    {swap,{x,0},{x,1}}.
     {line,[{location,"couch_key_tree.erl",313}]}.
-    {call,4,{f,69}}.
+    {call,4,{f,68}}.
     {'%',
         {var_info,
             {x,0},
@@ -1114,75 +1109,75 @@
                                    #{2 => {t_cons,{t_tuple,0,false,#{}},nil}}},
                                nil}}}}]}}.
     {get_tuple_element,{x,0},0,{x,1}}.
-    {get_tuple_element,{x,0},1,{y,0}}.
+    {move,{y,1},{x,2}}.
+    {move,{x,0},{y,1}}.
     {move,{x,1},{x,0}}.
-    {move,{y,2},{x,1}}.
-    {init_yregs,{list,[{y,2}]}}.
+    {move,{x,2},{x,1}}.
     {line,[{location,"couch_key_tree.erl",314}]}.
     {call_ext,2,{extfunc,erlang,'++',2}}.
-    {move,{y,0},{x,1}}.
+    {get_tuple_element,{y,1},1,{x,1}}.
     {move,{x,0},{x,2}}.
-    {move,{y,1},{x,0}}.
-    {call_last,3,{f,65},3}.
-  {label,67}.
-    {test,is_nil,{f,64},[{x,0}]}.
+    {move,{y,0},{x,0}}.
+    {call_last,3,{f,64},2}.
+  {label,66}.
+    {test,is_nil,{f,63},[{x,0}]}.
     {test_heap,3,3}.
     {put_tuple2,{x,0},{list,[{x,2},{x,1}]}}.
     return.
 
 
-{function, get_full_key_paths, 4, 69}.
-  {label,68}.
+{function, get_full_key_paths, 4, 68}.
+  {label,67}.
     {line,[{location,"couch_key_tree.erl",316}]}.
     {func_info,{atom,couch_key_tree},{atom,get_full_key_paths},4}.
-  {label,69}.
+  {label,68}.
     {'%',{var_info,{x,3},[{type,{t_list,{t_tuple,2,true,#{}},nil}}]}}.
-    {test,is_nil,{f,70},[{x,2}]}.
+    {test,is_nil,{f,69},[{x,2}]}.
     {move,{literal,{[],[]}},{x,0}}.
     return.
-  {label,70}.
-    {test,is_nonempty_list,{f,73},[{x,1}]}.
+  {label,69}.
+    {test,is_nonempty_list,{f,72},[{x,1}]}.
     {get_list,{x,1},{x,4},{x,5}}.
-    {test,is_tuple,{f,68},[{x,4}]}.
-    {test,test_arity,{f,68},[{x,4},3]}.
-    {allocate_heap,7,5,6}.
-    {move,{x,5},{y,3}}.
-    {move,{x,3},{y,4}}.
-    {move,{x,2},{y,5}}.
-    {move,{x,0},{y,6}}.
-    {get_tuple_element,{x,4},0,{y,2}}.
-    {get_tuple_element,{x,4},1,{y,1}}.
-    {get_tuple_element,{x,4},2,{y,0}}.
-    {put_tuple2,{x,0},{list,[{x,0},{y,2}]}}.
+    {test,is_tuple,{f,67},[{x,4}]}.
+    {test,test_arity,{f,67},[{x,4},3]}.
+    {allocate_heap,6,5,6}.
+    {move,{x,4},{y,1}}.
+    {move,{x,5},{y,2}}.
+    {move,{x,3},{y,3}}.
+    {move,{x,2},{y,4}}.
+    {move,{x,0},{y,5}}.
+    {get_tuple_element,{x,4},0,{y,0}}.
+    {put_tuple2,{x,0},{list,[{x,0},{y,0}]}}.
     {put_list,{x,0},nil,{x,1}}.
     {move,{x,2},{x,0}}.
     {line,[{location,"couch_key_tree.erl",321}]}.
     {call_ext,2,{extfunc,erlang,'--',2}}.
     {line,[{location,"couch_key_tree.erl",323}]}.
     {gc_bif,length,{f,0},1,[{x,0}],{x,1}}.
-    {gc_bif,length,{f,0},2,[{y,5}],{x,2}}.
-    {test,is_eq_exact,{f,71},[{x,1},{x,2}]}.
-    {move,nil,{y,5}}.
-    {jump,{f,72}}.
-  {label,71}.
-    {test_heap,10,1}.
-    {put_tuple2,{x,1},{list,[{y,2},{y,1}]}}.
-    {put_list,{x,1},{y,4},{x,1}}.
-    {put_tuple2,{x,1},{list,[{y,6},{x,1}]}}.
+    {gc_bif,length,{f,0},2,[{y,4}],{x,2}}.
+    {get_tuple_element,{y,1},1,{x,3}}.
+    {test,is_eq_exact,{f,70},[{x,1},{x,2}]}.
+    {move,nil,{y,4}}.
+    {jump,{f,71}}.
+  {label,70}.
+    {test_heap,10,4}.
+    {put_tuple2,{x,1},{list,[{y,0},{x,3}]}}.
+    {put_list,{x,1},{y,3},{x,1}}.
+    {put_tuple2,{x,1},{list,[{y,5},{x,1}]}}.
     {put_list,{x,1},nil,{x,1}}.
-    {move,{x,1},{y,5}}.
-  {label,72}.
+    {move,{x,1},{y,4}}.
+  {label,71}.
     {line,[{location,"couch_key_tree.erl",331}]}.
-    {gc_bif,'+',{f,0},1,[{y,6},{integer,1}],{x,1}}.
-    {test_heap,5,2}.
-    {put_tuple2,{x,2},{list,[{y,2},{y,1}]}}.
-    {put_list,{x,2},{y,4},{x,3}}.
-    {move,{x,0},{x,2}}.
-    {move,{x,1},{x,0}}.
-    {move,{y,0},{x,1}}.
-    {init_yregs,{list,[{y,2}]}}.
-    {trim,2,5}.
-    {call,4,{f,69}}.
+    {gc_bif,'+',{f,0},4,[{y,5},{integer,1}],{x,1}}.
+    {test_heap,5,4}.
+    {put_tuple2,{x,2},{list,[{y,0},{x,3}]}}.
+    {put_list,{x,2},{y,3},{x,3}}.
+    {get_tuple_element,{y,1},2,{x,2}}.
+    {swap,{x,2},{x,1}}.
+    {swap,{x,0},{x,2}}.
+    {init_yregs,{list,[{y,1}]}}.
+    {trim,1,5}.
+    {call,4,{f,68}}.
     {'%',
         {var_info,
             {x,0},
@@ -1200,7 +1195,7 @@
     {move,{y,4},{x,0}}.
     {init_yregs,{list,[{y,1},{y,2},{y,4}]}}.
     {line,[{location,"couch_key_tree.erl",334}]}.
-    {call,4,{f,69}}.
+    {call,4,{f,68}}.
     {'%',
         {var_info,
             {x,0},
@@ -1212,7 +1207,7 @@
                                    #{2 => {t_cons,{t_tuple,0,false,#{}},nil}}},
                                nil}}}}]}}.
     {get_tuple_element,{x,0},0,{x,1}}.
-    {get_tuple_element,{x,0},1,{y,4}}.
+    {move,{x,0},{y,4}}.
     {move,{y,0},{x,0}}.
     {trim,3,2}.
     {line,[{location,"couch_key_tree.erl",335}]}.
@@ -1222,30 +1217,31 @@
     {trim,1,1}.
     {call_ext,2,{extfunc,erlang,'++',2}}.
     {test_heap,3,1}.
-    {put_tuple2,{x,0},{list,[{x,0},{y,0}]}}.
+    {get_tuple_element,{y,0},1,{x,1}}.
+    {put_tuple2,{x,0},{list,[{x,0},{x,1}]}}.
     {deallocate,1}.
     return.
-  {label,73}.
-    {test,is_nil,{f,68},[{x,1}]}.
+  {label,72}.
+    {test,is_nil,{f,67},[{x,1}]}.
     {test_heap,3,3}.
     {put_tuple2,{x,0},{list,[nil,{x,2}]}}.
     return.
 
 
-{function, get_all_leafs_full, 1, 75}.
-  {label,74}.
+{function, get_all_leafs_full, 1, 74}.
+  {label,73}.
     {line,[{location,"couch_key_tree.erl",337}]}.
     {func_info,{atom,couch_key_tree},{atom,get_all_leafs_full},1}.
-  {label,75}.
+  {label,74}.
     {move,nil,{x,1}}.
-    {call_only,2,{f,77}}.
+    {call_only,2,{f,76}}.
 
 
-{function, get_all_leafs_full, 2, 77}.
-  {label,76}.
+{function, get_all_leafs_full, 2, 76}.
+  {label,75}.
     {line,[{location,"couch_key_tree.erl",340}]}.
     {func_info,{atom,couch_key_tree},{atom,get_all_leafs_full},2}.
-  {label,77}.
+  {label,76}.
     {'%',
         {var_info,
             {x,1},
@@ -1254,19 +1250,19 @@
                      {t_tuple,2,true,
                          #{2 => {t_cons,{t_tuple,2,true,#{}},nil}}},
                      nil}}]}}.
-    {test,is_nonempty_list,{f,78},[{x,0}]}.
+    {test,is_nonempty_list,{f,77},[{x,0}]}.
     {get_list,{x,0},{x,2},{x,3}}.
-    {test,is_tuple,{f,76},[{x,2}]}.
-    {test,test_arity,{f,76},[{x,2},2]}.
+    {test,is_tuple,{f,75},[{x,2}]}.
+    {test,test_arity,{f,75},[{x,2},2]}.
     {allocate_heap,2,2,4}.
     {move,{x,3},{y,0}}.
     {move,{x,1},{y,1}}.
+    {get_tuple_element,{x,2},1,{x,0}}.
+    {put_list,{x,0},nil,{x,1}}.
     {get_tuple_element,{x,2},0,{x,0}}.
-    {get_tuple_element,{x,2},1,{x,1}}.
-    {put_list,{x,1},nil,{x,1}}.
     {move,nil,{x,2}}.
     {line,[{location,"couch_key_tree.erl",343}]}.
-    {call,3,{f,80}}.
+    {call,3,{f,79}}.
     {'%',
         {var_info,
             {x,0},
@@ -1280,27 +1276,27 @@
     {call_ext,2,{extfunc,erlang,'++',2}}.
     {move,{x,0},{x,1}}.
     {move,{y,0},{x,0}}.
-    {call_last,2,{f,77},2}.
-  {label,78}.
-    {test,is_nil,{f,76},[{x,0}]}.
+    {call_last,2,{f,76},2}.
+  {label,77}.
+    {test,is_nil,{f,75},[{x,0}]}.
     {move,{x,1},{x,0}}.
     return.
 
 
-{function, get_all_leafs_full_simple, 3, 80}.
-  {label,79}.
+{function, get_all_leafs_full_simple, 3, 79}.
+  {label,78}.
     {line,[{location,"couch_key_tree.erl",345}]}.
     {func_info,{atom,couch_key_tree},{atom,get_all_leafs_full_simple},3}.
-  {label,80}.
+  {label,79}.
     {'%',{var_info,{x,2},[{type,{t_list,{t_tuple,2,true,#{}},nil}}]}}.
-    {test,is_nonempty_list,{f,82},[{x,1}]}.
+    {test,is_nonempty_list,{f,81},[{x,1}]}.
     {get_list,{x,1},{x,3},{x,4}}.
-    {test,is_tuple,{f,79},[{x,3}]}.
-    {test,test_arity,{f,79},[{x,3},3]}.
+    {test,is_tuple,{f,78},[{x,3}]}.
+    {test,test_arity,{f,78},[{x,3},3]}.
     {get_tuple_element,{x,3},0,{x,1}}.
     {get_tuple_element,{x,3},1,{x,5}}.
     {get_tuple_element,{x,3},2,{x,3}}.
-    {test,is_nil,{f,81},[{x,3}]}.
+    {test,is_nil,{f,80},[{x,3}]}.
     {allocate,4,6}.
     {move,{x,1},{y,0}}.
     {move,{x,5},{y,1}}.
@@ -1308,7 +1304,7 @@
     {move,{x,0},{y,3}}.
     {move,{x,4},{x,1}}.
     {line,[{location,"couch_key_tree.erl",348}]}.
-    {call,3,{f,80}}.
+    {call,3,{f,79}}.
     {'%',
         {var_info,
             {x,0},
@@ -1324,7 +1320,7 @@
     {put_list,{x,1},{x,0},{x,0}}.
     {deallocate,4}.
     return.
-  {label,81}.
+  {label,80}.
     {line,[{location,"couch_key_tree.erl",350}]}.
     {gc_bif,'+',{f,0},6,[{x,0},{integer,1}],{x,6}}.
     {allocate_heap,3,5,7}.
@@ -1335,7 +1331,7 @@
     {put_list,{x,0},{x,2},{x,2}}.
     {move,{x,3},{x,1}}.
     {move,{x,6},{x,0}}.
-    {call,3,{f,80}}.
+    {call,3,{f,79}}.
     {'%',
         {var_info,
             {x,0},
@@ -1351,7 +1347,7 @@
     {trim,2,1}.
     {move,{x,3},{x,0}}.
     {line,[{location,"couch_key_tree.erl",351}]}.
-    {call,3,{f,80}}.
+    {call,3,{f,79}}.
     {'%',
         {var_info,
             {x,0},
@@ -1364,26 +1360,26 @@
     {move,{y,0},{x,0}}.
     {line,[{location,"couch_key_tree.erl",350}]}.
     {call_ext_last,2,{extfunc,erlang,'++',2},1}.
-  {label,82}.
-    {test,is_nil,{f,79},[{x,1}]}.
+  {label,81}.
+    {test,is_nil,{f,78},[{x,1}]}.
     {move,nil,{x,0}}.
     return.
 
 
-{function, get_all_leafs, 1, 84}.
-  {label,83}.
+{function, get_all_leafs, 1, 83}.
+  {label,82}.
     {line,[{location,"couch_key_tree.erl",353}]}.
     {func_info,{atom,couch_key_tree},{atom,get_all_leafs},1}.
-  {label,84}.
+  {label,83}.
     {move,nil,{x,1}}.
-    {call_only,2,{f,86}}.
+    {call_only,2,{f,85}}.
 
 
-{function, get_all_leafs, 2, 86}.
-  {label,85}.
+{function, get_all_leafs, 2, 85}.
+  {label,84}.
     {line,[{location,"couch_key_tree.erl",356}]}.
     {func_info,{atom,couch_key_tree},{atom,get_all_leafs},2}.
-  {label,86}.
+  {label,85}.
     {'%',
         {var_info,
             {x,1},
@@ -1392,19 +1388,19 @@
                      {t_tuple,2,true,
                          #{2 => {t_tuple,2,true,#{2 => {t_cons,any,nil}}}}},
                      nil}}]}}.
-    {test,is_nonempty_list,{f,87},[{x,0}]}.
+    {test,is_nonempty_list,{f,86},[{x,0}]}.
     {get_list,{x,0},{x,2},{x,3}}.
-    {test,is_tuple,{f,85},[{x,2}]}.
-    {test,test_arity,{f,85},[{x,2},2]}.
+    {test,is_tuple,{f,84},[{x,2}]}.
+    {test,test_arity,{f,84},[{x,2},2]}.
     {allocate_heap,2,2,4}.
     {move,{x,3},{y,0}}.
     {move,{x,1},{y,1}}.
+    {get_tuple_element,{x,2},1,{x,0}}.
+    {put_list,{x,0},nil,{x,1}}.
     {get_tuple_element,{x,2},0,{x,0}}.
-    {get_tuple_element,{x,2},1,{x,1}}.
-    {put_list,{x,1},nil,{x,1}}.
     {move,nil,{x,2}}.
     {line,[{location,"couch_key_tree.erl",359}]}.
-    {call,3,{f,89}}.
+    {call,3,{f,88}}.
     {'%',
         {var_info,
             {x,0},
@@ -1418,27 +1414,27 @@
     {call_ext,2,{extfunc,erlang,'++',2}}.
     {move,{x,0},{x,1}}.
     {move,{y,0},{x,0}}.
-    {call_last,2,{f,86},2}.
-  {label,87}.
-    {test,is_nil,{f,85},[{x,0}]}.
+    {call_last,2,{f,85},2}.
+  {label,86}.
+    {test,is_nil,{f,84},[{x,0}]}.
     {move,{x,1},{x,0}}.
     return.
 
 
-{function, get_all_leafs_simple, 3, 89}.
-  {label,88}.
+{function, get_all_leafs_simple, 3, 88}.
+  {label,87}.
     {line,[{location,"couch_key_tree.erl",361}]}.
     {func_info,{atom,couch_key_tree},{atom,get_all_leafs_simple},3}.
-  {label,89}.
+  {label,88}.
     {'%',{var_info,{x,2},[{type,{t_list,any,nil}}]}}.
-    {test,is_nonempty_list,{f,91},[{x,1}]}.
+    {test,is_nonempty_list,{f,90},[{x,1}]}.
     {get_list,{x,1},{x,3},{x,4}}.
-    {test,is_tuple,{f,88},[{x,3}]}.
-    {test,test_arity,{f,88},[{x,3},3]}.
+    {test,is_tuple,{f,87},[{x,3}]}.
+    {test,test_arity,{f,87},[{x,3},3]}.
     {get_tuple_element,{x,3},0,{x,1}}.
     {get_tuple_element,{x,3},1,{x,5}}.
     {get_tuple_element,{x,3},2,{x,3}}.
-    {test,is_nil,{f,90},[{x,3}]}.
+    {test,is_nil,{f,89},[{x,3}]}.
     {allocate,4,6}.
     {move,{x,1},{y,0}}.
     {move,{x,5},{y,1}}.
@@ -1446,7 +1442,7 @@
     {move,{x,0},{y,3}}.
     {move,{x,4},{x,1}}.
     {line,[{location,"couch_key_tree.erl",364}]}.
-    {call,3,{f,89}}.
+    {call,3,{f,88}}.
     {'%',
         {var_info,
             {x,0},
@@ -1462,7 +1458,7 @@
     {put_list,{x,1},{x,0},{x,0}}.
     {deallocate,4}.
     return.
-  {label,90}.
+  {label,89}.
     {line,[{location,"couch_key_tree.erl",366}]}.
     {gc_bif,'+',{f,0},5,[{x,0},{integer,1}],{x,5}}.
     {allocate_heap,3,2,6}.
@@ -1472,7 +1468,7 @@
     {put_list,{x,1},{x,2},{x,2}}.
     {move,{x,3},{x,1}}.
     {move,{x,5},{x,0}}.
-    {call,3,{f,89}}.
+    {call,3,{f,88}}.
     {'%',
         {var_info,
             {x,0},
@@ -1488,7 +1484,7 @@
     {trim,2,1}.
     {move,{x,3},{x,0}}.
     {line,[{location,"couch_key_tree.erl",367}]}.
-    {call,3,{f,89}}.
+    {call,3,{f,88}}.
     {'%',
         {var_info,
             {x,0},
@@ -1501,131 +1497,131 @@
     {move,{y,0},{x,0}}.
     {line,[{location,"couch_key_tree.erl",366}]}.
     {call_ext_last,2,{extfunc,erlang,'++',2},1}.
-  {label,91}.
-    {test,is_nil,{f,88},[{x,1}]}.
+  {label,90}.
+    {test,is_nil,{f,87},[{x,1}]}.
     {move,nil,{x,0}}.
     return.
 
 
-{function, count_leafs, 1, 93}.
-  {label,92}.
+{function, count_leafs, 1, 92}.
+  {label,91}.
     {line,[{location,"couch_key_tree.erl",369}]}.
     {func_info,{atom,couch_key_tree},{atom,count_leafs},1}.
-  {label,93}.
-    {test,is_nonempty_list,{f,94},[{x,0}]}.
+  {label,92}.
+    {test,is_nonempty_list,{f,93},[{x,0}]}.
     {get_list,{x,0},{x,1},{x,2}}.
-    {test,is_tuple,{f,92},[{x,1}]}.
-    {test,test_arity,{f,92},[{x,1},2]}.
+    {test,is_tuple,{f,91},[{x,1}]}.
+    {test,test_arity,{f,91},[{x,1},2]}.
     {allocate_heap,1,2,3}.
     {move,{x,2},{y,0}}.
     {get_tuple_element,{x,1},1,{x,0}}.
     {put_list,{x,0},nil,{x,0}}.
     {line,[{location,"couch_key_tree.erl",372}]}.
-    {call,1,{f,96}}.
+    {call,1,{f,95}}.
     {'%',{var_info,{x,0},[{type,{t_integer,any}}]}}.
     {swap,{y,0},{x,0}}.
-    {call,1,{f,93}}.
+    {call,1,{f,92}}.
     {'%',{var_info,{x,0},[{type,{t_integer,any}}]}}.
     {gc_bif,'+',{f,0},1,[{y,0},{x,0}],{x,0}}.
     {deallocate,1}.
     return.
-  {label,94}.
-    {test,is_nil,{f,92},[{x,0}]}.
+  {label,93}.
+    {test,is_nil,{f,91},[{x,0}]}.
     {move,{integer,0},{x,0}}.
     return.
 
 
-{function, count_leafs_simple, 1, 96}.
-  {label,95}.
+{function, count_leafs_simple, 1, 95}.
+  {label,94}.
     {line,[{location,"couch_key_tree.erl",374}]}.
     {func_info,{atom,couch_key_tree},{atom,count_leafs_simple},1}.
-  {label,96}.
-    {test,is_nonempty_list,{f,98},[{x,0}]}.
+  {label,95}.
+    {test,is_nonempty_list,{f,97},[{x,0}]}.
     {get_list,{x,0},{x,1},{x,2}}.
-    {test,is_tuple,{f,95},[{x,1}]}.
-    {test,test_arity,{f,95},[{x,1},3]}.
+    {test,is_tuple,{f,94},[{x,1}]}.
+    {test,test_arity,{f,94},[{x,1},3]}.
     {get_tuple_element,{x,1},2,{x,0}}.
-    {test,is_nil,{f,97},[{x,0}]}.
+    {test,is_nil,{f,96},[{x,0}]}.
     {allocate,0,3}.
     {move,{x,2},{x,0}}.
     {line,[{location,"couch_key_tree.erl",377}]}.
-    {call,1,{f,96}}.
+    {call,1,{f,95}}.
     {'%',{var_info,{x,0},[{type,{t_integer,any}}]}}.
     {gc_bif,'+',{f,0},1,[{x,0},{integer,1}],{x,0}}.
     {deallocate,0}.
     return.
-  {label,97}.
+  {label,96}.
     {allocate,1,3}.
     {move,{x,2},{y,0}}.
     {line,[{location,"couch_key_tree.erl",379}]}.
-    {call,1,{f,96}}.
+    {call,1,{f,95}}.
     {'%',{var_info,{x,0},[{type,{t_integer,any}}]}}.
     {swap,{y,0},{x,0}}.
-    {call,1,{f,96}}.
+    {call,1,{f,95}}.
     {'%',{var_info,{x,0},[{type,{t_integer,any}}]}}.
     {gc_bif,'+',{f,0},1,[{y,0},{x,0}],{x,0}}.
     {deallocate,1}.
     return.
-  {label,98}.
-    {test,is_nil,{f,95},[{x,0}]}.
+  {label,97}.
+    {test,is_nil,{f,94},[{x,0}]}.
     {move,{integer,0},{x,0}}.
     return.
 
 
-{function, fold, 3, 100}.
-  {label,99}.
+{function, fold, 3, 99}.
+  {label,98}.
     {line,[{location,"couch_key_tree.erl",381}]}.
     {func_info,{atom,couch_key_tree},{atom,fold},3}.
-  {label,100}.
-    {test,is_nonempty_list,{f,101},[{x,2}]}.
+  {label,99}.
+    {test,is_nonempty_list,{f,100},[{x,2}]}.
     {get_list,{x,2},{x,3},{x,4}}.
-    {test,is_tuple,{f,99},[{x,3}]}.
-    {test,test_arity,{f,99},[{x,3},2]}.
+    {test,is_tuple,{f,98},[{x,3}]}.
+    {test,test_arity,{f,98},[{x,3},2]}.
     {allocate_heap,2,2,5}.
     {move,{x,4},{y,0}}.
     {move,{x,0},{y,1}}.
-    {get_tuple_element,{x,3},0,{x,2}}.
     {get_tuple_element,{x,3},1,{x,0}}.
-    {put_list,{x,0},nil,{x,3}}.
+    {put_list,{x,0},nil,{x,0}}.
+    {get_tuple_element,{x,3},0,{x,2}}.
+    {move,{x,0},{x,3}}.
     {move,{y,1},{x,0}}.
     {line,[{location,"couch_key_tree.erl",384}]}.
-    {call,4,{f,103}}.
+    {call,4,{f,102}}.
     {move,{x,0},{x,1}}.
     {move,{y,0},{x,2}}.
     {move,{y,1},{x,0}}.
-    {call_last,3,{f,100},2}.
-  {label,101}.
-    {test,is_nil,{f,99},[{x,2}]}.
+    {call_last,3,{f,99},2}.
+  {label,100}.
+    {test,is_nil,{f,98},[{x,2}]}.
     {move,{x,1},{x,0}}.
     return.
 
 
-{function, fold_simple, 4, 103}.
-  {label,102}.
+{function, fold_simple, 4, 102}.
+  {label,101}.
     {line,[{location,"couch_key_tree.erl",387}]}.
     {func_info,{atom,couch_key_tree},{atom,fold_simple},4}.
-  {label,103}.
-    {test,is_nonempty_list,{f,106},[{x,3}]}.
+  {label,102}.
+    {test,is_nonempty_list,{f,105},[{x,3}]}.
     {get_list,{x,3},{x,4},{x,5}}.
-    {test,is_tuple,{f,102},[{x,4}]}.
-    {test,test_arity,{f,102},[{x,4},3]}.
+    {test,is_tuple,{f,101},[{x,4}]}.
+    {test,test_arity,{f,101},[{x,4},3]}.
     {allocate,4,6}.
     {move,{x,5},{y,1}}.
     {move,{x,2},{y,2}}.
     {move,{x,0},{y,3}}.
-    {get_tuple_element,{x,4},0,{x,0}}.
-    {get_tuple_element,{x,4},1,{x,2}}.
     {get_tuple_element,{x,4},2,{y,0}}.
-    {test,is_nil,{f,104},[{y,0}]}.
-    {move,{atom,leaf},{x,3}}.
-    {jump,{f,105}}.
+    {test,is_nil,{f,103},[{y,0}]}.
+    {move,{atom,leaf},{x,2}}.
+    {jump,{f,104}}.
+  {label,103}.
+    {move,{atom,branch},{x,2}}.
   {label,104}.
-    {move,{atom,branch},{x,3}}.
-  {label,105}.
-    {test_heap,3,4}.
+    {test_heap,3,5}.
+    {get_tuple_element,{x,4},0,{x,0}}.
     {put_tuple2,{x,0},{list,[{y,2},{x,0}]}}.
+    {get_tuple_element,{x,4},1,{x,3}}.
     {move,{y,3},{x,4}}.
-    {swap,{x,3},{x,2}}.
     {swap,{x,1},{x,3}}.
     {line,[{location,"couch_key_tree.erl",395}]}.
     {call_fun,4}.
@@ -1635,48 +1631,50 @@
     {move,{y,0},{x,3}}.
     {trim,1,3}.
     {move,{y,2},{x,0}}.
-    {call,4,{f,103}}.
+    {call,4,{f,102}}.
     {move,{y,1},{x,2}}.
     {move,{x,0},{x,1}}.
     {move,{y,0},{x,3}}.
     {move,{y,2},{x,0}}.
-    {call_last,4,{f,103},3}.
-  {label,106}.
-    {test,is_nil,{f,102},[{x,3}]}.
+    {call_last,4,{f,102},3}.
+  {label,105}.
+    {test,is_nil,{f,101},[{x,3}]}.
     {move,{x,1},{x,0}}.
     return.
 
 
-{function, map, 2, 108}.
-  {label,107}.
+{function, map, 2, 107}.
+  {label,106}.
     {line,[{location,"couch_key_tree.erl",399}]}.
     {func_info,{atom,couch_key_tree},{atom,map},2}.
-  {label,108}.
-    {test,is_nonempty_list,{f,111},[{x,1}]}.
+  {label,107}.
+    {test,is_nonempty_list,{f,110},[{x,1}]}.
     {get_list,{x,1},{x,2},{x,3}}.
-    {test,is_tuple,{f,107},[{x,2}]}.
-    {test,test_arity,{f,107},[{x,2},2]}.
+    {test,is_tuple,{f,106},[{x,2}]}.
+    {test,test_arity,{f,106},[{x,2},2]}.
     {allocate,4,4}.
+    {init_yregs,{list,[{y,0}]}}.
+    {move,{x,2},{y,1}}.
     {move,{x,3},{y,2}}.
     {move,{x,0},{y,3}}.
-    {get_tuple_element,{x,2},0,{y,1}}.
-    {get_tuple_element,{x,2},1,{y,0}}.
     {move,{atom,arity},{x,1}}.
     {line,[{location,"couch_key_tree.erl",402}]}.
     {call_ext,2,{extfunc,erlang,fun_info,2}}.
-    {test,is_tagged_tuple,{f,114},[{x,0},2,{atom,arity}]}.
+    {test,is_tagged_tuple,{f,113},[{x,0},2,{atom,arity}]}.
     {get_tuple_element,{x,0},1,{x,1}}.
+    {get_tuple_element,{y,1},0,{y,0}}.
+    {get_tuple_element,{y,1},1,{x,2}}.
     {select_val,{x,1},
-                {f,114},
-                {list,[{integer,2},{f,110},{integer,3},{f,109}]}}.
-  {label,109}.
-    {test_heap,2,0}.
-    {put_list,{y,0},nil,{x,2}}.
-    {move,{y,1},{x,1}}.
-    {init_yregs,{list,[{y,0}]}}.
+                {f,113},
+                {list,[{integer,2},{f,109},{integer,3},{f,108}]}}.
+  {label,108}.
+    {test_heap,2,3}.
+    {put_list,{x,2},nil,{x,2}}.
+    {move,{y,0},{x,1}}.
+    {init_yregs,{list,[{y,1}]}}.
     {move,{y,3},{x,0}}.
     {line,[{location,"couch_key_tree.erl",407}]}.
-    {call,3,{f,116}}.
+    {call,3,{f,115}}.
     {'%',
         {var_info,
             {x,0},
@@ -1688,15 +1686,15 @@
                                    {t_tuple,3,true,#{3 => {t_list,any,any}}},
                                    nil}}},
                      nil}}]}}.
-    {get_list,{x,0},{y,0},{x,1}}.
-    {test,is_nil,{f,112},[{x,1}]}.
+    {get_list,{x,0},{y,1},{x,1}}.
+    {test,is_nil,{f,111},[{x,1}]}.
     {move,{y,2},{x,1}}.
     {move,{y,3},{x,0}}.
     {move,{y,0},{y,3}}.
     {move,{y,1},{y,2}}.
     {trim,2,2}.
     {line,[{location,"couch_key_tree.erl",408}]}.
-    {call,2,{f,108}}.
+    {call,2,{f,107}}.
     {'%',
      {var_info,
       {x,0},
@@ -1706,18 +1704,18 @@
           #{2 => {t_tuple,3,true,#{3 => {t_list,{t_tuple,0,false,#{}},nil}}}}},
          nil}}]}}.
     {test_heap,5,1}.
-    {put_tuple2,{x,1},{list,[{y,0},{y,1}]}}.
+    {put_tuple2,{x,1},{list,[{y,1},{y,0}]}}.
     {put_list,{x,1},{x,0},{x,0}}.
     {deallocate,2}.
     return.
-  {label,110}.
-    {test_heap,{alloc,[{words,3},{floats,0},{funs,1}]},0}.
-    {make_fun3,{f,233},0,0,{x,0},{list,[{y,3}]}}.
-    {put_list,{y,0},nil,{x,2}}.
-    {move,{y,1},{x,1}}.
-    {init_yregs,{list,[{y,0}]}}.
+  {label,109}.
+    {test_heap,{alloc,[{words,3},{floats,0},{funs,1}]},3}.
+    {make_fun3,{f,232},0,0,{x,0},{list,[{y,3}]}}.
+    {put_list,{x,2},nil,{x,2}}.
+    {move,{y,0},{x,1}}.
+    {init_yregs,{list,[{y,1}]}}.
     {line,[{location,"couch_key_tree.erl",404}]}.
-    {call,3,{f,116}}.
+    {call,3,{f,115}}.
     {'%',
         {var_info,
             {x,0},
@@ -1729,15 +1727,15 @@
                                    {t_tuple,3,true,#{3 => {t_list,any,any}}},
                                    nil}}},
                      nil}}]}}.
-    {get_list,{x,0},{y,0},{x,1}}.
-    {test,is_nil,{f,113},[{x,1}]}.
+    {get_list,{x,0},{y,1},{x,1}}.
+    {test,is_nil,{f,112},[{x,1}]}.
     {move,{y,2},{x,1}}.
     {move,{y,3},{x,0}}.
     {move,{y,0},{y,3}}.
     {move,{y,1},{y,2}}.
     {trim,2,2}.
     {line,[{location,"couch_key_tree.erl",405}]}.
-    {call,2,{f,108}}.
+    {call,2,{f,107}}.
     {'%',
      {var_info,
       {x,0},
@@ -1747,61 +1745,62 @@
           #{2 => {t_tuple,3,true,#{3 => {t_list,{t_tuple,0,false,#{}},nil}}}}},
          nil}}]}}.
     {test_heap,5,1}.
-    {put_tuple2,{x,1},{list,[{y,0},{y,1}]}}.
+    {put_tuple2,{x,1},{list,[{y,1},{y,0}]}}.
     {put_list,{x,1},{x,0},{x,0}}.
     {deallocate,2}.
     return.
-  {label,111}.
-    {test,is_nil,{f,107},[{x,1}]}.
+  {label,110}.
+    {test,is_nil,{f,106},[{x,1}]}.
     {move,nil,{x,0}}.
     return.
-  {label,112}.
+  {label,111}.
     {line,[{location,"couch_key_tree.erl",407}]}.
     {badmatch,{x,0}}.
-  {label,113}.
+  {label,112}.
     {line,[{location,"couch_key_tree.erl",404}]}.
     {badmatch,{x,0}}.
-  {label,114}.
+  {label,113}.
     {line,[{location,"couch_key_tree.erl",402}]}.
     {case_end,{x,0}}.
 
 
-{function, map_simple, 3, 116}.
-  {label,115}.
+{function, map_simple, 3, 115}.
+  {label,114}.
     {line,[{location,"couch_key_tree.erl",411}]}.
     {func_info,{atom,couch_key_tree},{atom,map_simple},3}.
-  {label,116}.
-    {test,is_nonempty_list,{f,119},[{x,2}]}.
+  {label,115}.
+    {test,is_nonempty_list,{f,118},[{x,2}]}.
     {get_list,{x,2},{x,3},{x,4}}.
-    {test,is_tuple,{f,115},[{x,3}]}.
-    {test,test_arity,{f,115},[{x,3},3]}.
+    {test,is_tuple,{f,114},[{x,3}]}.
+    {test,test_arity,{f,114},[{x,3},3]}.
     {allocate,5,5}.
+    {init_yregs,{list,[{y,0}]}}.
     {move,{x,4},{y,2}}.
     {move,{x,1},{y,3}}.
     {move,{x,0},{y,4}}.
-    {get_tuple_element,{x,3},0,{y,1}}.
-    {get_tuple_element,{x,3},1,{x,0}}.
-    {get_tuple_element,{x,3},2,{y,0}}.
-    {test,is_nil,{f,117},[{y,0}]}.
-    {move,{atom,leaf},{x,1}}.
-    {jump,{f,118}}.
+    {get_tuple_element,{x,3},2,{y,1}}.
+    {test,is_nil,{f,116},[{y,1}]}.
+    {move,{atom,leaf},{x,0}}.
+    {jump,{f,117}}.
+  {label,116}.
+    {move,{atom,branch},{x,0}}.
   {label,117}.
-    {move,{atom,branch},{x,1}}.
-  {label,118}.
-    {test_heap,3,2}.
-    {put_tuple2,{x,2},{list,[{y,3},{y,1}]}}.
+    {test_heap,3,4}.
+    {get_tuple_element,{x,3},0,{y,0}}.
+    {put_tuple2,{x,1},{list,[{y,3},{y,0}]}}.
+    {get_tuple_element,{x,3},1,{x,2}}.
     {move,{y,4},{x,3}}.
-    {swap,{x,1},{x,2}}.
-    {swap,{x,0},{x,1}}.
+    {swap,{x,2},{x,1}}.
+    {swap,{x,0},{x,2}}.
     {line,[{location,"couch_key_tree.erl",414}]}.
     {call_fun,3}.
     {line,[{location,"couch_key_tree.erl",422}]}.
     {gc_bif,'+',{f,0},1,[{y,3},{integer,1}],{x,1}}.
-    {move,{y,0},{x,2}}.
+    {move,{y,1},{x,2}}.
     {move,{y,4},{x,3}}.
-    {move,{x,0},{y,0}}.
+    {move,{x,0},{y,1}}.
     {move,{x,3},{x,0}}.
-    {call,3,{f,116}}.
+    {call,3,{f,115}}.
     {'%',
         {var_info,
             {x,0},
@@ -1821,7 +1820,7 @@
     {move,{y,1},{y,2}}.
     {trim,2,3}.
     {move,{x,3},{x,0}}.
-    {call,3,{f,116}}.
+    {call,3,{f,115}}.
     {'%',
         {var_info,
             {x,0},
@@ -1834,36 +1833,37 @@
                                    nil}}},
                      nil}}]}}.
     {test_heap,6,1}.
-    {put_tuple2,{x,1},{list,[{y,0},{y,1},{y,2}]}}.
+    {put_tuple2,{x,1},{list,[{y,1},{y,0},{y,2}]}}.
     {put_list,{x,1},{x,0},{x,0}}.
     {deallocate,3}.
     return.
-  {label,119}.
-    {test,is_nil,{f,115},[{x,2}]}.
+  {label,118}.
+    {test,is_nil,{f,114},[{x,2}]}.
     {move,nil,{x,0}}.
     return.
 
 
-{function, mapfold, 3, 121}.
-  {label,120}.
+{function, mapfold, 3, 120}.
+  {label,119}.
     {line,[{location,"couch_key_tree.erl",424}]}.
     {func_info,{atom,couch_key_tree},{atom,mapfold},3}.
-  {label,121}.
-    {test,is_nonempty_list,{f,122},[{x,2}]}.
+  {label,120}.
+    {test,is_nonempty_list,{f,121},[{x,2}]}.
     {get_list,{x,2},{x,3},{x,4}}.
-    {test,is_tuple,{f,120},[{x,3}]}.
-    {test,test_arity,{f,120},[{x,3},2]}.
+    {test,is_tuple,{f,119},[{x,3}]}.
+    {test,test_arity,{f,119},[{x,3},2]}.
     {allocate_heap,4,2,5}.
     {init_yregs,{list,[{y,0}]}}.
     {move,{x,4},{y,2}}.
     {move,{x,0},{y,3}}.
-    {get_tuple_element,{x,3},0,{y,1}}.
     {get_tuple_element,{x,3},1,{x,0}}.
-    {put_list,{x,0},nil,{x,3}}.
+    {put_list,{x,0},nil,{x,0}}.
+    {get_tuple_element,{x,3},0,{y,1}}.
     {move,{y,1},{x,2}}.
+    {move,{x,0},{x,3}}.
     {move,{y,3},{x,0}}.
     {line,[{location,"couch_key_tree.erl",427}]}.
-    {call,4,{f,125}}.
+    {call,4,{f,124}}.
     {'%',
         {var_info,
             {x,0},
@@ -1875,17 +1875,16 @@
                                    #{3 => {t_list,{t_tuple,0,false,#{}},nil}}},
                                nil}}}}]}}.
     {get_tuple_element,{x,0},0,{x,1}}.
-    {get_tuple_element,{x,0},1,{x,2}}.
     {get_list,{x,1},{y,0},{x,1}}.
-    {test,is_nil,{f,123},[{x,1}]}.
-    {move,{x,2},{x,1}}.
+    {test,is_nil,{f,122},[{x,1}]}.
+    {get_tuple_element,{x,0},1,{x,1}}.
     {move,{y,2},{x,2}}.
     {move,{y,3},{x,0}}.
     {move,{y,0},{y,3}}.
     {move,{y,1},{y,2}}.
     {trim,2,2}.
     {line,[{location,"couch_key_tree.erl",428}]}.
-    {call,3,{f,121}}.
+    {call,3,{f,120}}.
     {'%',
      {var_info,
       {x,0},
@@ -1904,57 +1903,55 @@
     {put_tuple2,{x,0},{list,[{x,1},{x,0}]}}.
     {deallocate,2}.
     return.
-  {label,122}.
-    {test,is_nil,{f,120},[{x,2}]}.
+  {label,121}.
+    {test,is_nil,{f,119},[{x,2}]}.
     {test_heap,3,2}.
     {put_tuple2,{x,0},{list,[nil,{x,1}]}}.
     return.
-  {label,123}.
+  {label,122}.
     {line,[{location,"couch_key_tree.erl",427}]}.
     {badmatch,{x,0}}.
 
 
-{function, mapfold_simple, 4, 125}.
-  {label,124}.
+{function, mapfold_simple, 4, 124}.
+  {label,123}.
     {line,[{location,"couch_key_tree.erl",431}]}.
     {func_info,{atom,couch_key_tree},{atom,mapfold_simple},4}.
-  {label,125}.
-    {test,is_nonempty_list,{f,128},[{x,3}]}.
+  {label,124}.
+    {test,is_nonempty_list,{f,127},[{x,3}]}.
     {get_list,{x,3},{x,4},{x,5}}.
-    {test,is_tuple,{f,124},[{x,4}]}.
-    {test,test_arity,{f,124},[{x,4},3]}.
+    {test,is_tuple,{f,123},[{x,4}]}.
+    {test,test_arity,{f,123},[{x,4},3]}.
     {allocate,6,6}.
-    {init_yregs,{list,[{y,0}]}}.
+    {init_yregs,{list,[{y,0},{y,1}]}}.
     {move,{x,5},{y,3}}.
     {move,{x,2},{y,4}}.
     {move,{x,0},{y,5}}.
-    {get_tuple_element,{x,4},0,{y,2}}.
-    {get_tuple_element,{x,4},1,{x,0}}.
-    {get_tuple_element,{x,4},2,{y,1}}.
-    {test,is_nil,{f,126},[{y,1}]}.
+    {get_tuple_element,{x,4},2,{y,2}}.
+    {test,is_nil,{f,125},[{y,2}]}.
     {move,{atom,leaf},{x,2}}.
-    {jump,{f,127}}.
-  {label,126}.
+    {jump,{f,126}}.
+  {label,125}.
     {move,{atom,branch},{x,2}}.
-  {label,127}.
-    {test_heap,3,3}.
-    {put_tuple2,{x,3},{list,[{y,4},{y,2}]}}.
+  {label,126}.
+    {test_heap,3,5}.
+    {get_tuple_element,{x,4},0,{y,1}}.
+    {put_tuple2,{x,0},{list,[{y,4},{y,1}]}}.
+    {get_tuple_element,{x,4},1,{x,3}}.
     {move,{y,5},{x,4}}.
     {swap,{x,1},{x,3}}.
-    {swap,{x,0},{x,1}}.
     {line,[{location,"couch_key_tree.erl",434}]}.
     {call_fun,4}.
-    {test,is_tuple,{f,129},[{x,0}]}.
-    {test,test_arity,{f,129},[{x,0},2]}.
+    {test,is_tuple,{f,128},[{x,0}]}.
+    {test,test_arity,{f,128},[{x,0},2]}.
     {get_tuple_element,{x,0},0,{y,0}}.
-    {get_tuple_element,{x,0},1,{x,0}}.
     {line,[{location,"couch_key_tree.erl",443}]}.
     {gc_bif,'+',{f,0},1,[{y,4},{integer,1}],{x,2}}.
-    {move,{x,0},{x,1}}.
-    {move,{y,1},{x,3}}.
-    {init_yregs,{list,[{y,1}]}}.
+    {get_tuple_element,{x,0},1,{x,1}}.
+    {move,{y,2},{x,3}}.
+    {init_yregs,{list,[{y,2}]}}.
     {move,{y,5},{x,0}}.
-    {call,4,{f,125}}.
+    {call,4,{f,124}}.
     {'%',
         {var_info,
             {x,0},
@@ -1965,7 +1962,7 @@
                                {t_tuple,3,true,
                                    #{3 => {t_list,{t_tuple,0,false,#{}},nil}}},
                                nil}}}}]}}.
-    {get_tuple_element,{x,0},0,{y,1}}.
+    {get_tuple_element,{x,0},0,{y,2}}.
     {get_tuple_element,{x,0},1,{x,1}}.
     {move,{y,3},{x,3}}.
     {move,{y,4},{x,2}}.
@@ -1975,7 +1972,7 @@
     {move,{y,2},{y,3}}.
     {trim,3,3}.
     {line,[{location,"couch_key_tree.erl",444}]}.
-    {call,4,{f,125}}.
+    {call,4,{f,124}}.
     {'%',
         {var_info,
             {x,0},
@@ -1989,41 +1986,42 @@
     {test_heap,9,1}.
     {get_tuple_element,{x,0},0,{x,1}}.
     {get_tuple_element,{x,0},1,{x,0}}.
-    {put_tuple2,{x,2},{list,[{y,0},{y,2},{y,1}]}}.
+    {put_tuple2,{x,2},{list,[{y,1},{y,2},{y,0}]}}.
     {put_list,{x,2},{x,1},{x,1}}.
     {put_tuple2,{x,0},{list,[{x,1},{x,0}]}}.
     {deallocate,3}.
     return.
-  {label,128}.
-    {test,is_nil,{f,124},[{x,3}]}.
+  {label,127}.
+    {test,is_nil,{f,123},[{x,3}]}.
     {test_heap,3,2}.
     {put_tuple2,{x,0},{list,[nil,{x,1}]}}.
     return.
-  {label,129}.
+  {label,128}.
     {line,[{location,"couch_key_tree.erl",434}]}.
     {badmatch,{x,0}}.
 
 
-{function, map_leafs, 2, 131}.
-  {label,130}.
+{function, map_leafs, 2, 130}.
+  {label,129}.
     {line,[{location,"couch_key_tree.erl",447}]}.
     {func_info,{atom,couch_key_tree},{atom,map_leafs},2}.
-  {label,131}.
-    {test,is_nonempty_list,{f,132},[{x,1}]}.
+  {label,130}.
+    {test,is_nonempty_list,{f,131},[{x,1}]}.
     {get_list,{x,1},{x,2},{x,3}}.
-    {test,is_tuple,{f,130},[{x,2}]}.
-    {test,test_arity,{f,130},[{x,2},2]}.
+    {test,is_tuple,{f,129},[{x,2}]}.
+    {test,test_arity,{f,129},[{x,2},2]}.
     {allocate_heap,4,2,4}.
     {init_yregs,{list,[{y,0}]}}.
     {move,{x,3},{y,2}}.
     {move,{x,0},{y,3}}.
-    {get_tuple_element,{x,2},0,{y,1}}.
     {get_tuple_element,{x,2},1,{x,0}}.
-    {put_list,{x,0},nil,{x,2}}.
+    {put_list,{x,0},nil,{x,0}}.
+    {get_tuple_element,{x,2},0,{y,1}}.
     {move,{y,1},{x,1}}.
+    {move,{x,0},{x,2}}.
     {move,{y,3},{x,0}}.
     {line,[{location,"couch_key_tree.erl",450}]}.
-    {call,3,{f,135}}.
+    {call,3,{f,134}}.
     {'%',
         {var_info,
             {x,0},
@@ -2036,14 +2034,14 @@
                                    nil}}},
                      nil}}]}}.
     {get_list,{x,0},{y,0},{x,1}}.
-    {test,is_nil,{f,133},[{x,1}]}.
+    {test,is_nil,{f,132},[{x,1}]}.
     {move,{y,2},{x,1}}.
     {move,{y,3},{x,0}}.
     {move,{y,0},{y,3}}.
     {move,{y,1},{y,2}}.
     {trim,2,2}.
     {line,[{location,"couch_key_tree.erl",451}]}.
-    {call,2,{f,131}}.
+    {call,2,{f,130}}.
     {'%',
      {var_info,
       {x,0},
@@ -2057,28 +2055,28 @@
     {put_list,{x,1},{x,0},{x,0}}.
     {deallocate,2}.
     return.
-  {label,132}.
-    {test,is_nil,{f,130},[{x,1}]}.
+  {label,131}.
+    {test,is_nil,{f,129},[{x,1}]}.
     {move,nil,{x,0}}.
     return.
-  {label,133}.
+  {label,132}.
     {line,[{location,"couch_key_tree.erl",450}]}.
     {badmatch,{x,0}}.
 
 
-{function, map_leafs_simple, 3, 135}.
-  {label,134}.
+{function, map_leafs_simple, 3, 134}.
+  {label,133}.
     {line,[{location,"couch_key_tree.erl",453}]}.
     {func_info,{atom,couch_key_tree},{atom,map_leafs_simple},3}.
-  {label,135}.
-    {test,is_nonempty_list,{f,137},[{x,2}]}.
+  {label,134}.
+    {test,is_nonempty_list,{f,136},[{x,2}]}.
     {get_list,{x,2},{x,3},{x,4}}.
-    {test,is_tuple,{f,134},[{x,3}]}.
-    {test,test_arity,{f,134},[{x,3},3]}.
+    {test,is_tuple,{f,133},[{x,3}]}.
+    {test,test_arity,{f,133},[{x,3},3]}.
     {get_tuple_element,{x,3},0,{x,2}}.
     {get_tuple_element,{x,3},1,{x,5}}.
     {get_tuple_element,{x,3},2,{x,3}}.
-    {test,is_nil,{f,136},[{x,3}]}.
+    {test,is_nil,{f,135},[{x,3}]}.
     {allocate_heap,4,3,6}.
     {move,{x,2},{y,0}}.
     {move,{x,4},{y,1}}.
@@ -2097,7 +2095,7 @@
     {trim,2,2}.
     {move,{x,3},{x,0}}.
     {line,[{location,"couch_key_tree.erl",457}]}.
-    {call,3,{f,135}}.
+    {call,3,{f,134}}.
     {'%',
         {var_info,
             {x,0},
@@ -2114,7 +2112,7 @@
     {put_list,{x,1},{x,0},{x,0}}.
     {deallocate,2}.
     return.
-  {label,136}.
+  {label,135}.
     {line,[{location,"couch_key_tree.erl",459}]}.
     {gc_bif,'+',{f,0},6,[{x,1},{integer,1}],{x,6}}.
     {allocate,5,7}.
@@ -2125,7 +2123,7 @@
     {move,{x,0},{y,4}}.
     {move,{x,3},{x,2}}.
     {move,{x,6},{x,1}}.
-    {call,3,{f,135}}.
+    {call,3,{f,134}}.
     {'%',
         {var_info,
             {x,0},
@@ -2145,7 +2143,7 @@
     {move,{y,1},{y,2}}.
     {trim,2,3}.
     {move,{x,3},{x,0}}.
-    {call,3,{f,135}}.
+    {call,3,{f,134}}.
     {'%',
         {var_info,
             {x,0},
@@ -2162,24 +2160,24 @@
     {put_list,{x,1},{x,0},{x,0}}.
     {deallocate,3}.
     return.
-  {label,137}.
-    {test,is_nil,{f,134},[{x,2}]}.
+  {label,136}.
+    {test,is_nil,{f,133},[{x,2}]}.
     {move,nil,{x,0}}.
     return.
 
 
-{function, stem, 2, 139}.
-  {label,138}.
+{function, stem, 2, 138}.
+  {label,137}.
     {line,[{location,"couch_key_tree.erl",461}]}.
     {func_info,{atom,couch_key_tree},{atom,stem},2}.
-  {label,139}.
+  {label,138}.
     {allocate,4,2}.
     {init_yregs,{list,[{y,0}]}}.
     {move,{x,1},{y,1}}.
     {move,{x,0},{y,2}}.
-    {'try',{y,3},{f,140}}.
+    {'try',{y,3},{f,139}}.
     {test_heap,{alloc,[{words,1},{floats,0},{funs,1}]},0}.
-    {make_fun3,{f,230},0,0,{y,0},{list,[{y,1}]}}.
+    {make_fun3,{f,229},0,0,{y,0},{list,[{y,1}]}}.
     {'%',{var_info,{y,0},[{fun_type,{t_tuple,2,true,#{}}}]}}.
     {line,[{location,"couch_key_tree.erl",468}]}.
     {call_ext,0,{extfunc,sets,new,0}}.
@@ -2190,8 +2188,8 @@
     {init_yregs,{list,[{y,0}]}}.
     {line,[{location,"couch_key_tree.erl",463}]}.
     {call_ext,3,{extfunc,lists,foldl,3}}.
-    {test,is_tuple,{f,142},[{x,0}]}.
-    {test,test_arity,{f,142},[{x,0},2]}.
+    {test,is_tuple,{f,141},[{x,0}]}.
+    {test,test_arity,{f,141},[{x,0},2]}.
     {get_tuple_element,{x,0},0,{x,1}}.
     {get_tuple_element,{x,0},1,{y,0}}.
     {move,{x,1},{x,0}}.
@@ -2209,27 +2207,27 @@
     {try_end,{y,3}}.
     {deallocate,4}.
     return.
-  {label,140}.
+  {label,139}.
     {try_case,{y,3}}.
-    {test,is_eq_exact,{f,141},[{x,0},{atom,throw}]}.
-    {test,is_eq_exact,{f,141},[{x,1},{atom,dupe_keys}]}.
+    {test,is_eq_exact,{f,140},[{x,0},{atom,throw}]}.
+    {test,is_eq_exact,{f,140},[{x,1},{atom,dupe_keys}]}.
     {move,{y,1},{x,1}}.
     {move,{y,2},{x,0}}.
-    {call_last,2,{f,161},4}.
-  {label,141}.
+    {call_last,2,{f,160},4}.
+  {label,140}.
     {bif,raise,{f,0},[{x,2},{x,1}],{x,0}}.
-  {label,142}.
+  {label,141}.
     {line,[{scope,[2]},{location,"couch_key_tree.erl",463}]}.
     {badmatch,{x,0}}.
 
 
-{function, stem_tree, 3, 144}.
-  {label,143}.
+{function, stem_tree, 3, 143}.
+  {label,142}.
     {line,[{location,"couch_key_tree.erl",478}]}.
     {func_info,{atom,couch_key_tree},{atom,stem_tree},3}.
-  {label,144}.
-    {test,is_tuple,{f,143},[{x,0}]}.
-    {test,test_arity,{f,143},[{x,0},2]}.
+  {label,143}.
+    {test,is_tuple,{f,142},[{x,0}]}.
+    {test,test_arity,{f,142},[{x,0},2]}.
     {allocate,1,3}.
     {get_tuple_element,{x,0},0,{y,0}}.
     {get_tuple_element,{x,0},1,{x,0}}.
@@ -2238,10 +2236,10 @@
     {move,{x,0},{x,1}}.
     {move,{y,0},{x,0}}.
     {line,[{location,"couch_key_tree.erl",479}]}.
-    {call,4,{f,149}}.
+    {call,4,{f,148}}.
     {'%',{var_info,{x,0},[{type,{t_tuple,3,false,#{2 => number}}}]}}.
-    {select_tuple_arity,{x,0},{f,147},{list,[3,{f,146},4,{f,145}]}}.
-  {label,145}.
+    {select_tuple_arity,{x,0},{f,146},{list,[3,{f,145},4,{f,144}]}}.
+  {label,144}.
     {test_heap,8,1}.
     {get_tuple_element,{x,0},0,{x,1}}.
     {get_tuple_element,{x,0},2,{x,2}}.
@@ -2251,91 +2249,91 @@
     {put_tuple2,{x,0},{list,[{x,1},{x,0}]}}.
     {deallocate,1}.
     return.
-  {label,146}.
+  {label,145}.
     {test_heap,3,1}.
     {get_tuple_element,{x,0},0,{x,1}}.
     {get_tuple_element,{x,0},2,{x,0}}.
     {put_tuple2,{x,0},{list,[{x,1},{x,0}]}}.
     {deallocate,1}.
     return.
-  {label,147}.
+  {label,146}.
     {case_end,{x,0}}.
 
 
-{function, stem_tree, 4, 149}.
-  {label,148}.
+{function, stem_tree, 4, 148}.
+  {label,147}.
     {line,[{location,"couch_key_tree.erl",486}]}.
     {func_info,{atom,couch_key_tree},{atom,stem_tree},4}.
-  {label,149}.
-    {test,is_tuple,{f,148},[{x,1}]}.
-    {test,test_arity,{f,148},[{x,1},3]}.
+  {label,148}.
+    {test,is_tuple,{f,147},[{x,1}]}.
+    {test,test_arity,{f,147},[{x,1},3]}.
     {get_tuple_element,{x,1},0,{x,4}}.
-    {get_tuple_element,{x,1},1,{x,5}}.
-    {get_tuple_element,{x,1},2,{x,6}}.
-    {test,is_nil,{f,150},[{x,6}]}.
+    {get_tuple_element,{x,1},2,{x,5}}.
+    {test,is_nil,{f,149},[{x,5}]}.
     {allocate,2,5}.
     {move,{x,2},{y,0}}.
     {move,{x,1},{y,1}}.
     {move,{x,3},{x,1}}.
     {move,{x,4},{x,0}}.
     {line,[{location,"couch_key_tree.erl",487}]}.
-    {call,2,{f,156}}.
+    {call,2,{f,155}}.
     {gc_bif,'-',{f,0},1,[{y,0},{integer,1}],{x,1}}.
     {test_heap,5,2}.
     {put_tuple2,{x,0},{list,[{x,0},{x,1},{y,1},nil]}}.
     {deallocate,2}.
     return.
-  {label,150}.
-    {allocate,6,7}.
+  {label,149}.
+    {allocate,6,6}.
     {init_yregs,{list,[{y,0}]}}.
     {move,{x,4},{y,1}}.
     {move,{x,5},{y,2}}.
-    {move,{x,6},{y,3}}.
-    {move,{x,2},{y,4}}.
+    {move,{x,2},{y,3}}.
+    {move,{x,1},{y,4}}.
     {move,{x,0},{y,5}}.
     {move,{x,3},{x,1}}.
     {move,{x,4},{x,0}}.
     {line,[{location,"couch_key_tree.erl",489}]}.
-    {call,2,{f,156}}.
+    {call,2,{f,155}}.
     {test_heap,{alloc,[{words,7},{floats,0},{funs,1}]},1}.
-    {make_fun3,{f,224},0,0,{x,1},{list,[{y,5},{y,4}]}}.
+    {make_fun3,{f,223},0,0,{x,1},{list,[{y,5},{y,3}]}}.
     {'%',{var_info,{x,1},[{fun_type,{t_tuple,4,true,#{}}}]}}.
     {put_tuple2,{x,0},{list,[{x,0},{integer,-1},nil,nil]}}.
-    {move,{y,3},{x,2}}.
+    {move,{y,2},{x,2}}.
     {swap,{x,0},{x,1}}.
-    {init_yregs,{list,[{y,3},{y,4}]}}.
+    {init_yregs,{list,[{y,2},{y,3}]}}.
     {line,[{location,"couch_key_tree.erl",490}]}.
     {call_ext,3,{extfunc,lists,foldl,3}}.
-    {test,is_tuple,{f,154},[{x,0}]}.
-    {test,test_arity,{f,154},[{x,0},4]}.
-    {get_tuple_element,{x,0},0,{y,4}}.
-    {get_tuple_element,{x,0},1,{y,3}}.
+    {test,is_tuple,{f,153},[{x,0}]}.
+    {test,test_arity,{f,153},[{x,0},4]}.
+    {get_tuple_element,{x,0},0,{y,3}}.
+    {get_tuple_element,{x,0},1,{y,2}}.
     {get_tuple_element,{x,0},2,{x,1}}.
     {get_tuple_element,{x,0},3,{y,0}}.
-    {test,is_lt,{f,151},[{integer,0},{y,3}]}.
-    {gc_bif,length,{f,151},2,[{x,1}],{x,0}}.
-    {test,is_lt,{f,151},[{integer,0},{x,0}]}.
+    {test,is_lt,{f,150},[{integer,0},{y,2}]}.
+    {gc_bif,length,{f,150},2,[{x,1}],{x,0}}.
+    {test,is_lt,{f,150},[{integer,0},{x,0}]}.
     {move,{y,0},{y,5}}.
     {trim,1,5}.
     {move,{x,1},{x,0}}.
     {line,[{location,"couch_key_tree.erl",511}]}.
     {call_ext,1,{extfunc,lists,reverse,1}}.
     {test_heap,4,1}.
-    {put_tuple2,{x,0},{list,[{y,0},{y,1},{x,0}]}}.
+    {get_tuple_element,{y,3},1,{x,1}}.
+    {put_tuple2,{x,0},{list,[{y,0},{x,1},{x,0}]}}.
     {line,[{location,"couch_key_tree.erl",512}]}.
-    {gc_bif,'-',{f,0},1,[{y,2},{integer,1}],{x,1}}.
+    {gc_bif,'-',{f,0},1,[{y,1},{integer,1}],{x,1}}.
     {test_heap,5,2}.
-    {put_tuple2,{x,0},{list,[{y,3},{x,1},{x,0},{y,4}]}}.
+    {put_tuple2,{x,0},{list,[{y,2},{x,1},{x,0},{y,4}]}}.
     {deallocate,5}.
     return.
-  {label,151}.
-    {test,is_eq_exact,{f,152},[{y,3},{integer,0}]}.
-    {gc_bif,length,{f,152},2,[{x,1}],{x,0}}.
-    {test,is_lt,{f,152},[{integer,0},{x,0}]}.
+  {label,150}.
+    {test,is_eq_exact,{f,151},[{y,2},{integer,0}]}.
+    {gc_bif,length,{f,151},2,[{x,1}],{x,0}}.
+    {test,is_lt,{f,151},[{integer,0},{x,0}]}.
     {test_heap,{alloc,[{words,1},{floats,0},{funs,1}]},2}.
-    {make_fun3,{f,222},0,0,{y,5},{list,[{y,5}]}}.
+    {make_fun3,{f,221},0,0,{y,5},{list,[{y,5}]}}.
     {'%',{var_info,{y,5},[{fun_type,{t_tuple,2,true,#{1 => number}}}]}}.
-    {move,{y,0},{y,3}}.
+    {move,{y,0},{y,4}}.
     {trim,3,3}.
     {move,{x,1},{x,0}}.
     {line,[{location,"couch_key_tree.erl",518}]}.
@@ -2346,73 +2344,73 @@
     {trim,1,2}.
     {line,[{location,"couch_key_tree.erl",514}]}.
     {call_ext,2,{extfunc,lists,map,2}}.
-    {move,{y,1},{x,1}}.
-    {init_yregs,{list,[{y,1}]}}.
+    {move,{y,0},{x,1}}.
+    {trim,1,1}.
     {line,[{location,"couch_key_tree.erl",520}]}.
     {call_ext,2,{extfunc,erlang,'++',2}}.
     {test_heap,4,1}.
     {put_tuple2,{x,0},{list,[{y,0},{integer,-1},{x,0}]}}.
-    {deallocate,2}.
+    {deallocate,1}.
     return.
-  {label,152}.
-    {test,is_lt,{f,153},[{y,3},{integer,0}]}.
-    {gc_bif,length,{f,153},2,[{x,1}],{x,0}}.
-    {test,is_eq_exact,{f,153},[{x,0},{integer,0}]}.
+  {label,151}.
+    {test,is_lt,{f,152},[{y,2},{integer,0}]}.
+    {gc_bif,length,{f,152},2,[{x,1}],{x,0}}.
+    {test,is_eq_exact,{f,152},[{x,0},{integer,0}]}.
     {line,[{location,"couch_key_tree.erl",522}]}.
-    {gc_bif,'-',{f,0},0,[{y,3},{integer,1}],{x,0}}.
+    {gc_bif,'-',{f,0},0,[{y,2},{integer,1}],{x,0}}.
     {test_heap,4,1}.
-    {put_tuple2,{x,0},{list,[{y,4},{x,0},{y,0}]}}.
+    {put_tuple2,{x,0},{list,[{y,3},{x,0},{y,0}]}}.
     {deallocate,6}.
     return.
-  {label,153}.
+  {label,152}.
     {line,[{location,"couch_key_tree.erl",509}]}.
-    {case_end,{y,3}}.
-  {label,154}.
+    {case_end,{y,2}}.
+  {label,153}.
     {line,[{location,"couch_key_tree.erl",508}]}.
     {badmatch,{x,0}}.
 
 
-{function, check_key, 2, 156}.
-  {label,155}.
+{function, check_key, 2, 155}.
+  {label,154}.
     {line,[{location,"couch_key_tree.erl",525}]}.
     {func_info,{atom,couch_key_tree},{atom,check_key},2}.
-  {label,156}.
+  {label,155}.
     {allocate,2,2}.
     {move,{x,1},{y,0}}.
     {move,{x,0},{y,1}}.
     {line,[{location,"couch_key_tree.erl",526}]}.
     {call_ext,2,{extfunc,sets,is_element,2}}.
     {select_val,{x,0},
-                {f,159},
-                {list,[{atom,false},{f,158},{atom,true},{f,157}]}}.
-  {label,157}.
+                {f,158},
+                {list,[{atom,false},{f,157},{atom,true},{f,156}]}}.
+  {label,156}.
     {move,{atom,dupe_keys},{x,0}}.
     {line,[{location,"couch_key_tree.erl",528}]}.
     {call_ext_last,1,{extfunc,erlang,throw,1},2}.
-  {label,158}.
+  {label,157}.
     {move,{y,0},{x,1}}.
     {move,{y,1},{x,0}}.
     {line,[{location,"couch_key_tree.erl",530}]}.
     {call_ext_last,2,{extfunc,sets,add_element,2},2}.
-  {label,159}.
+  {label,158}.
     {line,[{location,"couch_key_tree.erl",526}]}.
     {case_end,{x,0}}.
 
 
-{function, repair_tree, 2, 161}.
-  {label,160}.
+{function, repair_tree, 2, 160}.
+  {label,159}.
     {line,[{location,"couch_key_tree.erl",533}]}.
     {func_info,{atom,couch_key_tree},{atom,repair_tree},2}.
-  {label,161}.
+  {label,160}.
     {allocate_heap,1,{alloc,[{words,1},{floats,0},{funs,1}]},2}.
-    {make_fun3,{f,219},0,0,{y,0},{list,[{x,1}]}}.
+    {make_fun3,{f,218},0,0,{y,0},{list,[{x,1}]}}.
     {'%',
         {var_info,
             {y,0},
             [{fun_type,
                  {t_tuple,2,true,#{1 => number,2 => {t_list,any,nil}}}}]}}.
     {line,[{location,"couch_key_tree.erl",541}]}.
-    {call,1,{f,75}}.
+    {call,1,{f,74}}.
     {'%',
         {var_info,
             {x,0},
@@ -2429,7 +2427,7 @@
     {line,[{location,"couch_key_tree.erl",535}]}.
     {call_ext,1,{extfunc,lists,sort,1}}.
     {test_heap,{alloc,[{words,0},{floats,0},{funs,1}]},1}.
-    {make_fun3,{f,214},0,0,{x,1},{list,[]}}.
+    {make_fun3,{f,213},0,0,{x,1},{list,[]}}.
     {'%',{var_info,{x,1},[{fun_type,{t_list,any,nil}}]}}.
     {move,{x,0},{x,2}}.
     {move,{x,1},{x,0}}.
@@ -2438,53 +2436,53 @@
     {call_ext_last,3,{extfunc,lists,foldl,3},0}.
 
 
-{function, value_pref, 2, 163}.
-  {label,162}.
+{function, value_pref, 2, 162}.
+  {label,161}.
     {line,[{location,"couch_key_tree.erl",558}]}.
     {func_info,{atom,couch_key_tree},{atom,value_pref},2}.
+  {label,162}.
+    {test,is_tuple,{f,164},[{x,0}]}.
+    {test,test_arity,{f,163},[{x,0},3]}.
+    return.
   {label,163}.
-    {test,is_tuple,{f,165},[{x,0}]}.
-    {test,test_arity,{f,164},[{x,0},3]}.
+    {test,test_arity,{f,164},[{x,0},4]}.
     return.
   {label,164}.
-    {test,test_arity,{f,165},[{x,0},4]}.
-    return.
+    {test,is_tuple,{f,166},[{x,1}]}.
+    {test,test_arity,{f,165},[{x,1},3]}.
+    {jump,{f,167}}.
   {label,165}.
-    {test,is_tuple,{f,167},[{x,1}]}.
-    {test,test_arity,{f,166},[{x,1},3]}.
-    {jump,{f,168}}.
+    {test,test_arity,{f,166},[{x,1},4]}.
+    {jump,{f,167}}.
   {label,166}.
-    {test,test_arity,{f,167},[{x,1},4]}.
-    {jump,{f,168}}.
+    {test,is_nil,{f,168},[{x,0}]}.
   {label,167}.
-    {test,is_nil,{f,169},[{x,0}]}.
-  {label,168}.
     {move,{x,1},{x,0}}.
     return.
-  {label,169}.
+  {label,168}.
     return.
 
 
-{function, gen_and_stem, 0, 171}.
-  {label,170}.
+{function, gen_and_stem, 0, 170}.
+  {label,169}.
     {line,[{location,"couch_key_tree.erl",579}]}.
     {func_info,{atom,couch_key_tree},{atom,gen_and_stem},0}.
-  {label,171}.
+  {label,170}.
     {move,{float,8.0e-4},{x,1}}.
     {move,{literal,{1647,841737,351137}},{x,2}}.
     {move,{integer,7000},{x,0}}.
-    {call_only,3,{f,173}}.
+    {call_only,3,{f,172}}.
 
 
-{function, gen_and_stem, 3, 173}.
-  {label,172}.
+{function, gen_and_stem, 3, 172}.
+  {label,171}.
     {line,[{location,"couch_key_tree.erl",582}]}.
     {func_info,{atom,couch_key_tree},{atom,gen_and_stem},3}.
-  {label,173}.
+  {label,172}.
     {allocate,4,3}.
     {init_yregs,{list,[{y,0},{y,1},{y,2},{y,3}]}}.
     {line,[{location,"couch_key_tree.erl",583}]}.
-    {call,3,{f,177}}.
+    {call,3,{f,176}}.
     {'%',
      {var_info,
       {x,0},
@@ -2497,27 +2495,29 @@
                 2 =>
                  {t_tuple,3,true,#{2 => {t_atom,[x]},3 => {t_list,any,any}}}}},
              nil}}}}]}}.
-    {get_tuple_element,{x,0},1,{y,3}}.
+    {move,{x,0},{y,3}}.
     {line,[{location,"couch_key_tree.erl",584}]}.
     {call_ext,0,{extfunc,erlang,garbage_collect,0}}.
     {bif,self,{f,0},[],{x,0}}.
     {move,{integer,500},{x,1}}.
     {line,[{location,"couch_key_tree.erl",586}]}.
-    {call,2,{f,200}}.
+    {call,2,{f,199}}.
     {move,{x,0},{y,2}}.
     {line,[{location,"couch_key_tree.erl",587}]}.
     {call_ext,0,{extfunc,erlang,monotonic_time,0}}.
-    {swap,{y,3},{x,0}}.
+    {get_tuple_element,{y,3},1,{x,1}}.
+    {move,{x,0},{y,3}}.
+    {move,{x,1},{x,0}}.
     {move,{integer,1000},{x,1}}.
     {line,[{location,"couch_key_tree.erl",589}]}.
-    {call,2,{f,139}}.
+    {call,2,{f,138}}.
     {'%',{var_info,{x,0},[{type,{t_list,any,nil}}]}}.
     {line,[{location,"couch_key_tree.erl",591}]}.
     {call_ext,0,{extfunc,erlang,monotonic_time,0}}.
     {move,{x,0},{y,1}}.
     {move,{y,2},{x,0}}.
     {line,[{location,"couch_key_tree.erl",592}]}.
-    {call,1,{f,195}}.
+    {call,1,{f,194}}.
     {move,{x,0},{y,0}}.
     {line,[{location,"couch_key_tree.erl",594}]}.
     {call_ext,0,{extfunc,erlang,garbage_collect,0}}.
@@ -2535,29 +2535,29 @@
     {move,{y,1},{y,2}}.
     {trim,2,1}.
     {line,[{location,"couch_key_tree.erl",598}]}.
-    {call,2,{f,190}}.
+    {call,2,{f,189}}.
     {test_heap,3,1}.
     {put_tuple2,{x,0},{list,[{x,0},{y,0}]}}.
     {deallocate,1}.
     return.
 
 
-{function, gen, 0, 175}.
-  {label,174}.
+{function, gen, 0, 174}.
+  {label,173}.
     {line,[{location,"couch_key_tree.erl",601}]}.
     {func_info,{atom,couch_key_tree},{atom,gen},0}.
-  {label,175}.
+  {label,174}.
     {move,{float,8.0e-4},{x,1}}.
     {move,{literal,{1647,841737,351137}},{x,2}}.
     {move,{integer,7000},{x,0}}.
-    {call_only,3,{f,177}}.
+    {call_only,3,{f,176}}.
 
 
-{function, gen, 3, 177}.
-  {label,176}.
+{function, gen, 3, 176}.
+  {label,175}.
     {line,[{location,"couch_key_tree.erl",604}]}.
     {func_info,{atom,couch_key_tree},{atom,gen},3}.
-  {label,177}.
+  {label,176}.
     {allocate,3,3}.
     {move,{x,2},{y,0}}.
     {move,{x,1},{y,1}}.
@@ -2571,7 +2571,7 @@
     {move,{y,0},{y,2}}.
     {trim,2,1}.
     {line,[{location,"couch_key_tree.erl",606}]}.
-    {call,2,{f,184}}.
+    {call,2,{f,183}}.
     {'%',
         {var_info,
             {x,0},
@@ -2592,11 +2592,11 @@
     return.
 
 
-{function, save, 2, 179}.
-  {label,178}.
+{function, save, 2, 178}.
+  {label,177}.
     {line,[{location,"couch_key_tree.erl",608}]}.
     {func_info,{atom,couch_key_tree},{atom,save},2}.
-  {label,179}.
+  {label,178}.
     {allocate,1,2}.
     {move,{x,0},{y,0}}.
     {move,{x,1},{x,0}}.
@@ -2607,53 +2607,53 @@
     {call_ext_last,2,{extfunc,file,write_file,2},1}.
 
 
-{function, load, 1, 181}.
-  {label,180}.
+{function, load, 1, 180}.
+  {label,179}.
     {line,[{location,"couch_key_tree.erl",611}]}.
     {func_info,{atom,couch_key_tree},{atom,load},1}.
-  {label,181}.
+  {label,180}.
     {allocate,0,1}.
     {line,[{location,"couch_key_tree.erl",612}]}.
     {call_ext,1,{extfunc,file,read_file,1}}.
-    {test,is_tagged_tuple,{f,182},[{x,0},2,{atom,ok}]}.
+    {test,is_tagged_tuple,{f,181},[{x,0},2,{atom,ok}]}.
     {get_tuple_element,{x,0},1,{x,0}}.
     {line,[{location,"couch_key_tree.erl",613}]}.
     {call_ext_last,1,{extfunc,erlang,binary_to_term,1},0}.
-  {label,182}.
+  {label,181}.
     {line,[{location,"couch_key_tree.erl",612}]}.
     {badmatch,{x,0}}.
 
 
-{function, revnode, 2, 184}.
-  {label,183}.
+{function, revnode, 2, 183}.
+  {label,182}.
     {line,[{location,"couch_key_tree.erl",615}]}.
     {func_info,{atom,couch_key_tree},{atom,revnode},2}.
-  {label,184}.
-    {test,is_eq_exact,{f,185},[{x,0},{integer,0}]}.
+  {label,183}.
+    {test,is_eq_exact,{f,184},[{x,0},{integer,0}]}.
     {allocate,0,0}.
     {line,[{location,"couch_key_tree.erl",616}]}.
-    {call,0,{f,188}}.
+    {call,0,{f,187}}.
     {test_heap,4,1}.
     {put_tuple2,{x,0},{list,[{x,0},{atom,x},nil]}}.
     {deallocate,0}.
     return.
-  {label,185}.
+  {label,184}.
     {allocate,3,2}.
     {init_yregs,{list,[{y,0}]}}.
     {move,{x,1},{y,1}}.
     {move,{x,0},{y,2}}.
     {line,[{location,"couch_key_tree.erl",618}]}.
     {call_ext,0,{extfunc,rand,uniform,0}}.
-    {test,is_lt,{f,186},[{x,0},{y,1}]}.
+    {test,is_lt,{f,185},[{x,0},{y,1}]}.
     {line,[{location,"couch_key_tree.erl",620}]}.
-    {call,0,{f,188}}.
+    {call,0,{f,187}}.
     {line,[{location,"couch_key_tree.erl",621}]}.
     {gc_bif,'-',{f,0},1,[{y,2},{integer,1}],{x,1}}.
     {move,{x,0},{y,0}}.
     {move,{y,1},{x,2}}.
     {move,{x,1},{x,0}}.
     {move,{x,2},{x,1}}.
-    {call,2,{f,184}}.
+    {call,2,{f,183}}.
     {'%',
         {var_info,
             {x,0},
@@ -2674,7 +2674,7 @@
     {move,{x,2},{x,1}}.
     {move,{y,0},{y,1}}.
     {trim,1,2}.
-    {call,2,{f,184}}.
+    {call,2,{f,183}}.
     {'%',
         {var_info,
             {x,0},
@@ -2693,16 +2693,16 @@
     {put_tuple2,{x,0},{list,[{y,0},{atom,x},{x,0}]}}.
     {deallocate,2}.
     return.
-  {label,186}.
+  {label,185}.
     {line,[{location,"couch_key_tree.erl",625}]}.
-    {call,0,{f,188}}.
+    {call,0,{f,187}}.
     {gc_bif,'-',{f,0},1,[{y,2},{integer,1}],{x,1}}.
     {move,{x,0},{y,2}}.
     {move,{y,1},{x,2}}.
     {move,{x,1},{x,0}}.
     {move,{x,2},{x,1}}.
     {trim,2,1}.
-    {call,2,{f,184}}.
+    {call,2,{f,183}}.
     {'%',
         {var_info,
             {x,0},
@@ -2722,21 +2722,21 @@
     return.
 
 
-{function, rev, 0, 188}.
-  {label,187}.
+{function, rev, 0, 187}.
+  {label,186}.
     {line,[{location,"couch_key_tree.erl",628}]}.
     {func_info,{atom,couch_key_tree},{atom,rev},0}.
-  {label,188}.
+  {label,187}.
     {move,{integer,16},{x,0}}.
     {line,[{location,"couch_key_tree.erl",629}]}.
     {call_ext_only,1,{extfunc,crypto,strong_rand_bytes,1}}.
 
 
-{function, dt, 2, 190}.
-  {label,189}.
+{function, dt, 2, 189}.
+  {label,188}.
     {line,[{location,"couch_key_tree.erl",631}]}.
     {func_info,{atom,couch_key_tree},{atom,dt},2}.
-  {label,190}.
+  {label,189}.
     {line,[{location,"couch_key_tree.erl",632}]}.
     {gc_bif,'-',{f,0},2,[{x,0},{x,1}],{x,0}}.
     {move,{atom,second},{x,2}}.
@@ -2744,16 +2744,16 @@
     {call_ext_only,3,{extfunc,erlang,convert_time_unit,3}}.
 
 
-{function, mem_mb, 1, 192}.
-  {label,191}.
+{function, mem_mb, 1, 191}.
+  {label,190}.
     {line,[{location,"couch_key_tree.erl",634}]}.
     {func_info,{atom,couch_key_tree},{atom,mem_mb},1}.
-  {label,192}.
+  {label,191}.
     {allocate,0,1}.
     {move,{atom,memory},{x,1}}.
     {line,[{location,"couch_key_tree.erl",635}]}.
     {call_ext,2,{extfunc,erlang,process_info,2}}.
-    {test,is_tagged_tuple,{f,193},[{x,0},2,{atom,memory}]}.
+    {test,is_tagged_tuple,{f,192},[{x,0},2,{atom,memory}]}.
     {get_tuple_element,{x,0},1,{x,0}}.
     {line,[{location,"couch_key_tree.erl",636}]}.
     {gc_bif,'*',{f,0},1,[{x,0},{integer,8}],{x,0}}.
@@ -2765,52 +2765,52 @@
     {fmove,{fr,0},{x,0}}.
     {deallocate,0}.
     return.
-  {label,193}.
+  {label,192}.
     {line,[{location,"couch_key_tree.erl",635}]}.
     {badmatch,{x,0}}.
 
 
-{function, get_max_mem, 1, 195}.
-  {label,194}.
+{function, get_max_mem, 1, 194}.
+  {label,193}.
     {line,[{location,"couch_key_tree.erl",639}]}.
     {func_info,{atom,couch_key_tree},{atom,get_max_mem},1}.
-  {label,195}.
+  {label,194}.
     {allocate_heap,0,3,1}.
     {bif,self,{f,0},[],{x,1}}.
     {put_tuple2,{x,1},{list,[{atom,get_mem},{x,1}]}}.
     {line,[{location,"couch_key_tree.erl",640}]}.
     send.
-  {label,196}.
-    {loop_rec,{f,198},{x,0}}.
-    {test,is_tagged_tuple,{f,197},[{x,0},2,{atom,mem_max}]}.
+  {label,195}.
+    {loop_rec,{f,197},{x,0}}.
+    {test,is_tagged_tuple,{f,196},[{x,0},2,{atom,mem_max}]}.
     {get_tuple_element,{x,0},1,{x,0}}.
     remove_message.
     {deallocate,0}.
     return.
+  {label,196}.
+    {loop_rec_end,{f,195}}.
   {label,197}.
-    {loop_rec_end,{f,196}}.
-  {label,198}.
-    {wait,{f,196}}.
+    {wait,{f,195}}.
 
 
-{function, spawn_mem_sampler, 2, 200}.
-  {label,199}.
+{function, spawn_mem_sampler, 2, 199}.
+  {label,198}.
     {line,[{location,"couch_key_tree.erl",643}]}.
     {func_info,{atom,couch_key_tree},{atom,spawn_mem_sampler},2}.
-  {label,200}.
+  {label,199}.
     {'%',{var_info,{x,1},[{type,{t_integer,{500,500}}}]}}.
     {test_heap,{alloc,[{words,2},{floats,0},{funs,1}]},1}.
-    {make_fun3,{f,212},0,0,{x,0},{list,[{x,0},{integer,500}]}}.
+    {make_fun3,{f,211},0,0,{x,0},{list,[{x,0},{integer,500}]}}.
     {'%',{var_info,{x,0},[{fun_type,none}]}}.
     {line,[{location,"couch_key_tree.erl",644}]}.
     {call_ext_only,1,{extfunc,erlang,spawn_link,1}}.
 
 
-{function, mem_sampler, 3, 202}.
-  {label,201}.
+{function, mem_sampler, 3, 201}.
+  {label,200}.
     {line,[{location,"couch_key_tree.erl",646}]}.
     {func_info,{atom,couch_key_tree},{atom,mem_sampler},3}.
-  {label,202}.
+  {label,201}.
     {'%',{var_info,{x,1},[{type,{t_integer,{500,500}}}]}}.
     {allocate,2,3}.
     {move,{x,2},{y,0}}.
@@ -2820,87 +2820,88 @@
     {call_ext,1,{extfunc,timer,sleep,1}}.
     {move,{y,1},{x,0}}.
     {line,[{location,"couch_key_tree.erl",648}]}.
-    {call,1,{f,192}}.
+    {call,1,{f,191}}.
     {'%',{var_info,{x,0},[{type,{t_float,any}}]}}.
     {move,{y,0},{x,1}}.
     {init_yregs,{list,[{y,0}]}}.
     {call_ext,2,{extfunc,erlang,max,2}}.
     {move,{x,0},{y,0}}.
-  {label,203}.
-    {loop_rec,{f,205},{x,0}}.
-    {test,is_tagged_tuple,{f,204},[{x,0},2,{atom,get_mem}]}.
+  {label,202}.
+    {loop_rec,{f,204},{x,0}}.
+    {test,is_tagged_tuple,{f,203},[{x,0},2,{atom,get_mem}]}.
     {test_heap,3,1}.
-    {get_tuple_element,{x,0},1,{x,0}}.
     remove_message.
     {put_tuple2,{x,1},{list,[{atom,mem_max},{y,0}]}}.
+    {get_tuple_element,{x,0},1,{x,0}}.
     {line,[{location,"couch_key_tree.erl",651}]}.
     send.
-    {jump,{f,206}}.
+    {jump,{f,205}}.
+  {label,203}.
+    {loop_rec_end,{f,202}}.
   {label,204}.
-    {loop_rec_end,{f,203}}.
-  {label,205}.
     timeout.
-  {label,206}.
+  {label,205}.
     {move,{integer,500},{x,1}}.
     {move,{y,0},{x,2}}.
     {move,{y,1},{x,0}}.
-    {call_last,3,{f,202},2}.
+    {call_last,3,{f,201},2}.
 
 
-{function, module_info, 0, 208}.
-  {label,207}.
+{function, module_info, 0, 207}.
+  {label,206}.
     {line,[]}.
     {func_info,{atom,couch_key_tree},{atom,module_info},0}.
-  {label,208}.
+  {label,207}.
     {move,{atom,couch_key_tree},{x,0}}.
     {call_ext_only,1,{extfunc,erlang,get_module_info,1}}.
 
 
-{function, module_info, 1, 210}.
-  {label,209}.
+{function, module_info, 1, 209}.
+  {label,208}.
     {line,[]}.
     {func_info,{atom,couch_key_tree},{atom,module_info},1}.
-  {label,210}.
+  {label,209}.
     {move,{x,0},{x,1}}.
     {move,{atom,couch_key_tree},{x,0}}.
     {call_ext_only,2,{extfunc,erlang,get_module_info,2}}.
 
 
-{function, '-spawn_mem_sampler/2-fun-0-', 2, 212}.
-  {label,211}.
+{function, '-spawn_mem_sampler/2-fun-0-', 2, 211}.
+  {label,210}.
     {line,[{location,"couch_key_tree.erl",644}]}.
     {func_info,{atom,couch_key_tree},{atom,'-spawn_mem_sampler/2-fun-0-'},2}.
-  {label,212}.
+  {label,211}.
     {'%',{var_info,{x,1},[{type,{t_integer,{500,500}}}]}}.
     {allocate,1,1}.
     {move,{x,0},{y,0}}.
-    {call,1,{f,192}}.
+    {call,1,{f,191}}.
     {'%',{var_info,{x,0},[{type,{t_float,any}}]}}.
     {move,{integer,500},{x,1}}.
     {move,{x,0},{x,2}}.
     {move,{y,0},{x,0}}.
-    {call_last,3,{f,202},1}.
+    {call_last,3,{f,201},1}.
 
 
-{function, '-repair_tree/2-fun-2-', 2, 214}.
-  {label,213}.
+{function, '-repair_tree/2-fun-2-', 2, 213}.
+  {label,212}.
     {line,[{location,"couch_key_tree.erl",547}]}.
     {func_info,{atom,couch_key_tree},{atom,'-repair_tree/2-fun-2-'},2}.
-  {label,214}.
-    {test,is_tuple,{f,213},[{x,0}]}.
-    {test,test_arity,{f,213},[{x,0},2]}.
+  {label,213}.
+    {test,is_tuple,{f,212},[{x,0}]}.
+    {test,test_arity,{f,212},[{x,0},2]}.
     {allocate_heap,2,{alloc,[{words,0},{floats,0},{funs,1}]},2}.
     {move,{x,1},{y,1}}.
     {get_tuple_element,{x,0},0,{y,0}}.
+    {make_fun3,{f,216},0,0,{x,1},{list,[]}}.
+    {'%',{var_info,{x,1},[{fun_type,{t_cons,{t_tuple,3,true,#{}},nil}}]}}.
     {get_tuple_element,{x,0},1,{x,2}}.
-    {make_fun3,{f,217},0,0,{x,0},{list,[]}}.
-    {'%',{var_info,{x,0},[{fun_type,{t_cons,{t_tuple,3,true,#{}},nil}}]}}.
+    {move,{x,1},{x,0}}.
     {move,nil,{x,1}}.
     {line,[{location,"couch_key_tree.erl",548}]}.
     {call_ext,3,{extfunc,lists,foldl,3}}.
-    {test,is_nonempty_list,{f,215},[{x,0}]}.
+    {test,is_nonempty_list,{f,214},[{x,0}]}.
     {get_list,{x,0},{x,1},{x,2}}.
-    {test,is_nil,{f,215},[{x,2}]}.
+    {test,is_nil,{f,214},[{x,2}]}.
     {test_heap,3,2}.
     {put_tuple2,{x,1},{list,[{y,0},{x,1}]}}.
     {move,{y,1},{x,0}}.
@@ -2917,18 +2918,18 @@
     {get_tuple_element,{x,0},0,{x,0}}.
     {deallocate,0}.
     return.
-  {label,215}.
+  {label,214}.
     {line,[{location,"couch_key_tree.erl",548}]}.
     {badmatch,{x,0}}.
 
 
-{function, '-repair_tree/2-fun-1-', 2, 217}.
-  {label,216}.
+{function, '-repair_tree/2-fun-1-', 2, 216}.
+  {label,215}.
     {line,[{location,"couch_key_tree.erl",549}]}.
     {func_info,{atom,couch_key_tree},{atom,'-repair_tree/2-fun-1-'},2}.
-  {label,217}.
-    {test,is_tuple,{f,216},[{x,0}]}.
-    {test,test_arity,{f,216},[{x,0},2]}.
+  {label,216}.
+    {test,is_tuple,{f,215},[{x,0}]}.
+    {test,test_arity,{f,215},[{x,0},2]}.
     {test_heap,6,2}.
     {get_tuple_element,{x,0},0,{x,2}}.
     {get_tuple_element,{x,0},1,{x,0}}.
@@ -2937,13 +2938,13 @@
     return.
 
 
-{function, '-repair_tree/2-fun-0-', 2, 219}.
-  {label,218}.
+{function, '-repair_tree/2-fun-0-', 2, 218}.
+  {label,217}.
     {line,[{location,"couch_key_tree.erl",537}]}.
     {func_info,{atom,couch_key_tree},{atom,'-repair_tree/2-fun-0-'},2}.
-  {label,219}.
-    {test,is_tuple,{f,220},[{x,0}]}.
-    {test,test_arity,{f,220},[{x,0},2]}.
+  {label,218}.
+    {test,is_tuple,{f,219},[{x,0}]}.
+    {test,test_arity,{f,219},[{x,0},2]}.
     {allocate,1,2}.
     {get_tuple_element,{x,0},0,{y,0}}.
     {get_tuple_element,{x,0},1,{x,0}}.
@@ -2957,7 +2958,7 @@
     {put_tuple2,{x,0},{list,[{x,1},{x,0}]}}.
     {deallocate,1}.
     return.
-  {label,220}.
+  {label,219}.
     {test_heap,2,1}.
     {put_list,{x,0},nil,{x,1}}.
     {move,{atom,function_clause},{x,0}}.
@@ -2965,11 +2966,11 @@
     {call_ext_only,2,{extfunc,erlang,error,2}}.
 
 
-{function, '-stem_tree/4-fun-1-', 2, 222}.
-  {label,221}.
+{function, '-stem_tree/4-fun-1-', 2, 221}.
+  {label,220}.
     {line,[{location,"couch_key_tree.erl",515}]}.
     {func_info,{atom,couch_key_tree},{atom,'-stem_tree/4-fun-1-'},2}.
-  {label,222}.
+  {label,221}.
     {line,[{location,"couch_key_tree.erl",516}]}.
     {gc_bif,'+',{f,0},2,[{x,1},{integer,1}],{x,1}}.
     {test_heap,3,2}.
@@ -2977,107 +2978,98 @@
     return.
 
 
-{function, '-stem_tree/4-fun-0-', 4, 224}.
-  {label,223}.
+{function, '-stem_tree/4-fun-0-', 4, 223}.
+  {label,222}.
     {line,[{location,"couch_key_tree.erl",491}]}.
     {func_info,{atom,couch_key_tree},{atom,'-stem_tree/4-fun-0-'},4}.
-  {label,224}.
-    {test,is_tuple,{f,228},[{x,1}]}.
-    {test,test_arity,{f,228},[{x,1},4]}.
-    {get_tuple_element,{x,1},0,{x,4}}.
-    {get_tuple_element,{x,1},1,{x,5}}.
-    {get_tuple_element,{x,1},2,{x,6}}.
-    {get_tuple_element,{x,1},3,{x,1}}.
+  {label,223}.
+    {test,is_tuple,{f,227},[{x,1}]}.
+    {test,test_arity,{f,227},[{x,1},4]}.
     {line,[{location,"couch_key_tree.erl",493}]}.
-    {gc_bif,'+',{f,0},7,[{x,2},{integer,1}],{x,2}}.
-    {allocate,6,7}.
-    {init_yregs,{list,[{y,0},{y,1},{y,2}]}}.
-    {move,{x,5},{y,3}}.
-    {move,{x,6},{y,4}}.
-    {move,{x,1},{y,5}}.
-    {move,{x,0},{x,1}}.
-    {move,{x,2},{x,0}}.
-    {move,{x,3},{x,2}}.
-    {move,{x,4},{x,3}}.
-    {call,4,{f,149}}.
+    {gc_bif,'+',{f,0},4,[{x,2},{integer,1}],{x,2}}.
+    {allocate,3,4}.
+    {init_yregs,{list,[{y,0},{y,1}]}}.
+    {move,{x,1},{y,2}}.
+    {get_tuple_element,{x,1},0,{x,1}}.
+    {swap,{x,3},{x,2}}.
+    {swap,{x,1},{x,3}}.
+    {swap,{x,0},{x,1}}.
+    {call,4,{f,148}}.
     {'%',{var_info,{x,0},[{type,{t_tuple,3,false,#{2 => number}}}]}}.
-    {select_tuple_arity,{x,0},{f,227},{list,[3,{f,226},4,{f,225}]}}.
-  {label,225}.
-    {get_tuple_element,{x,0},0,{y,2}}.
-    {get_tuple_element,{x,0},1,{x,1}}.
-    {get_tuple_element,{x,0},2,{y,1}}.
-    {get_tuple_element,{x,0},3,{y,0}}.
-    {move,{x,1},{x,0}}.
-    {move,{y,3},{x,1}}.
-    {init_yregs,{list,[{y,3}]}}.
+    {get_tuple_element,{y,2},1,{x,1}}.
+    {get_tuple_element,{y,2},2,{y,1}}.
+    {get_tuple_element,{y,2},3,{y,2}}.
+    {move,{x,0},{y,0}}.
+    {select_tuple_arity,{x,0},{f,226},{list,[3,{f,225},4,{f,224}]}}.
+  {label,224}.
+    {get_tuple_element,{x,0},1,{x,0}}.
     {call_ext,2,{extfunc,erlang,max,2}}.
     {test_heap,2,1}.
-    {put_list,{y,1},{y,4},{y,4}}.
-    {move,{y,0},{x,2}}.
-    {move,{y,5},{x,1}}.
-    {move,{x,0},{y,5}}.
-    {trim,2,4}.
-    {move,{x,2},{x,0}}.
+    {get_tuple_element,{y,0},2,{x,1}}.
+    {put_list,{x,1},{y,1},{y,1}}.
+    {get_tuple_element,{y,0},3,{x,1}}.
+    {move,{y,2},{x,2}}.
+    {move,{x,0},{y,2}}.
+    {move,{x,1},{x,0}}.
+    {move,{x,2},{x,1}}.
     {line,[{location,"couch_key_tree.erl",497}]}.
     {call_ext,2,{extfunc,erlang,'++',2}}.
     {test_heap,5,1}.
-    {put_tuple2,{x,0},{list,[{y,0},{y,3},{y,2},{x,0}]}}.
-    {deallocate,4}.
+    {get_tuple_element,{y,0},0,{x,1}}.
+    {put_tuple2,{x,0},{list,[{x,1},{y,2},{y,1},{x,0}]}}.
+    {deallocate,3}.
     return.
-  {label,226}.
-    {get_tuple_element,{x,0},0,{y,2}}.
-    {get_tuple_element,{x,0},1,{x,1}}.
-    {get_tuple_element,{x,0},2,{y,1}}.
-    {move,{x,1},{x,0}}.
-    {move,{y,3},{x,1}}.
-    {init_yregs,{list,[{y,3}]}}.
+  {label,225}.
+    {get_tuple_element,{x,0},1,{x,0}}.
     {call_ext,2,{extfunc,erlang,max,2}}.
-    {move,{y,1},{x,2}}.
-    {move,{y,5},{x,1}}.
-    {move,{x,0},{y,5}}.
-    {trim,2,4}.
-    {move,{x,2},{x,0}}.
+    {get_tuple_element,{y,0},2,{x,1}}.
+    {move,{y,2},{x,2}}.
+    {move,{x,0},{y,2}}.
+    {move,{x,1},{x,0}}.
+    {move,{x,2},{x,1}}.
     {line,[{location,"couch_key_tree.erl",501}]}.
     {call_ext,2,{extfunc,erlang,'++',2}}.
     {test_heap,5,1}.
-    {put_tuple2,{x,0},{list,[{y,0},{y,3},{y,2},{x,0}]}}.
-    {deallocate,4}.
+    {get_tuple_element,{y,0},0,{x,1}}.
+    {put_tuple2,{x,0},{list,[{x,1},{y,2},{y,1},{x,0}]}}.
+    {deallocate,3}.
     return.
-  {label,227}.
+  {label,226}.
     {line,[{location,"couch_key_tree.erl",493}]}.
     {case_end,{x,0}}.
-  {label,228}.
+  {label,227}.
     {line,[{location,"couch_key_tree.erl",492}]}.
     {badmatch,{x,1}}.
 
 
-{function, '-stem/2-fun-0-', 3, 230}.
-  {label,229}.
+{function, '-stem/2-fun-0-', 3, 229}.
+  {label,228}.
     {line,[{location,"couch_key_tree.erl",464}]}.
     {func_info,{atom,couch_key_tree},{atom,'-stem/2-fun-0-'},3}.
-  {label,230}.
-    {test,is_tuple,{f,231},[{x,1}]}.
-    {test,test_arity,{f,231},[{x,1},2]}.
-    {allocate,2,3}.
-    {init_yregs,{list,[{y,0}]}}.
+  {label,229}.
+    {test,is_tuple,{f,230},[{x,1}]}.
+    {test,test_arity,{f,230},[{x,1},2]}.
+    {allocate,1,3}.
     {get_tuple_element,{x,1},0,{x,3}}.
-    {get_tuple_element,{x,1},1,{y,1}}.
+    {get_tuple_element,{x,1},1,{y,0}}.
     {move,{x,2},{x,1}}.
     {move,{x,3},{x,2}}.
     {line,[{location,"couch_key_tree.erl",465}]}.
-    {call,3,{f,144}}.
+    {call,3,{f,143}}.
     {'%',{var_info,{x,0},[{type,{t_tuple,2,true,#{}}}]}}.
-    {get_tuple_element,{x,0},0,{y,0}}.
-    {get_tuple_element,{x,0},1,{x,0}}.
-    {move,{y,1},{x,1}}.
-    {init_yregs,{list,[{y,1}]}}.
+    {get_tuple_element,{x,0},1,{x,1}}.
+    {move,{y,0},{x,2}}.
+    {move,{x,0},{y,0}}.
+    {move,{x,1},{x,0}}.
+    {move,{x,2},{x,1}}.
     {line,[{location,"couch_key_tree.erl",466}]}.
     {call_ext,2,{extfunc,erlang,'++',2}}.
     {test_heap,3,1}.
-    {put_tuple2,{x,0},{list,[{y,0},{x,0}]}}.
-    {deallocate,2}.
+    {get_tuple_element,{y,0},0,{x,1}}.
+    {put_tuple2,{x,0},{list,[{x,1},{x,0}]}}.
+    {deallocate,1}.
     return.
-  {label,231}.
+  {label,230}.
     {test_heap,4,2}.
     {put_list,{x,1},nil,{x,1}}.
     {put_list,{x,0},{x,1},{x,1}}.
@@ -3086,11 +3078,11 @@
     {call_ext_only,2,{extfunc,erlang,error,2}}.
 
 
-{function, '-map/2-fun-0-', 4, 233}.
-  {label,232}.
+{function, '-map/2-fun-0-', 4, 232}.
+  {label,231}.
     {line,[{location,"couch_key_tree.erl",404}]}.
     {func_info,{atom,couch_key_tree},{atom,'-map/2-fun-0-'},4}.
-  {label,233}.
+  {label,232}.
     {allocate,0,4}.
     {move,{x,3},{x,2}}.
     {call_fun,2}.
@@ -3098,11 +3090,11 @@
     return.
 
 
-{function, '-get/2-lc$^0/1-0-', 1, 235}.
-  {label,234}.
+{function, '-get/2-lc$^0/1-0-', 1, 234}.
+  {label,233}.
     {line,[{location,"couch_key_tree.erl",301}]}.
     {func_info,{atom,couch_key_tree},{atom,'-get/2-lc$^0/1-0-'},1}.
-  {label,235}.
+  {label,234}.
     {'%',
         {var_info,
             {x,0},
@@ -3111,23 +3103,23 @@
                      {t_tuple,2,true,
                          #{2 => {t_cons,{t_tuple,0,false,#{}},nil}}},
                      nil}}]}}.
-    {test,is_nonempty_list,{f,237},[{x,0}]}.
+    {test,is_nonempty_list,{f,236},[{x,0}]}.
     {get_list,{x,0},{x,1},{x,0}}.
     {get_tuple_element,{x,1},0,{x,2}}.
     {get_tuple_element,{x,1},1,{x,1}}.
     {get_hd,{x,1},{x,3}}.
-    {test,test_arity,{f,236},[{x,3},2]}.
+    {test,test_arity,{f,235},[{x,3},2]}.
     {allocate,3,4}.
+    {move,{x,3},{y,0}}.
     {move,{x,2},{y,1}}.
     {move,{x,0},{y,2}}.
-    {get_tuple_element,{x,3},1,{y,0}}.
     {move,{x,1},{x,0}}.
     {line,[{location,"couch_key_tree.erl",300}]}.
-    {call,1,{f,239}}.
+    {call,1,{f,238}}.
     {'%',{var_info,{x,0},[{type,{t_list,any,nil}}]}}.
     {swap,{y,2},{x,0}}.
     {line,[{location,"couch_key_tree.erl",301}]}.
-    {call,1,{f,235}}.
+    {call,1,{f,234}}.
     {'%',
         {var_info,
             {x,0},
@@ -3137,59 +3129,62 @@
                          #{2 => {t_tuple,2,true,#{2 => {t_list,any,nil}}}}},
                      nil}}]}}.
     {test_heap,8,1}.
-    {put_tuple2,{x,1},{list,[{y,1},{y,2}]}}.
-    {put_tuple2,{x,1},{list,[{y,0},{x,1}]}}.
+    {get_tuple_element,{y,0},1,{x,1}}.
+    {put_tuple2,{x,2},{list,[{y,1},{y,2}]}}.
+    {put_tuple2,{x,1},{list,[{x,1},{x,2}]}}.
     {put_list,{x,1},{x,0},{x,0}}.
     {deallocate,3}.
     return.
+  {label,235}.
+    {call_only,1,{f,234}}.
   {label,236}.
-    {call_only,1,{f,235}}.
-  {label,237}.
     return.
 
 
-{function, '-get/2-lc$^1/1-1-', 1, 239}.
-  {label,238}.
+{function, '-get/2-lc$^1/1-1-', 1, 238}.
+  {label,237}.
     {line,[{location,"couch_key_tree.erl",300}]}.
     {func_info,{atom,couch_key_tree},{atom,'-get/2-lc$^1/1-1-'},1}.
-  {label,239}.
+  {label,238}.
     {'%',{var_info,{x,0},[{type,{t_list,{t_tuple,0,false,#{}},nil}}]}}.
-    {test,is_nonempty_list,{f,241},[{x,0}]}.
+    {test,is_nonempty_list,{f,240},[{x,0}]}.
     {get_list,{x,0},{x,1},{x,0}}.
-    {test,test_arity,{f,240},[{x,1},2]}.
+    {test,test_arity,{f,239},[{x,1},2]}.
     {allocate,1,2}.
-    {get_tuple_element,{x,1},0,{y,0}}.
-    {call,1,{f,239}}.
+    {move,{x,1},{y,0}}.
+    {call,1,{f,238}}.
     {'%',{var_info,{x,0},[{type,{t_list,any,nil}}]}}.
     {test_heap,2,1}.
-    {put_list,{y,0},{x,0},{x,0}}.
+    {get_tuple_element,{y,0},0,{x,1}}.
+    {put_list,{x,1},{x,0},{x,0}}.
     {deallocate,1}.
     return.
+  {label,239}.
+    {call_only,1,{f,238}}.
   {label,240}.
-    {call_only,1,{f,239}}.
-  {label,241}.
     return.
 
 
-{function, '-remove_leafs/2-fun-2-', 2, 243}.
-  {label,242}.
+{function, '-remove_leafs/2-fun-2-', 2, 242}.
+  {label,241}.
     {line,[{location,"couch_key_tree.erl",230}]}.
     {func_info,{atom,couch_key_tree},{atom,'-remove_leafs/2-fun-2-'},2}.
-  {label,243}.
-    {test,is_tuple,{f,242},[{x,0}]}.
-    {test,test_arity,{f,242},[{x,0},2]}.
+  {label,242}.
+    {test,is_tuple,{f,241},[{x,0}]}.
+    {test,test_arity,{f,241},[{x,0},2]}.
     {allocate_heap,2,{alloc,[{words,0},{floats,0},{funs,1}]},2}.
     {move,{x,1},{y,1}}.
     {get_tuple_element,{x,0},0,{y,0}}.
+    {make_fun3,{f,245},0,0,{x,1},{list,[]}}.
+    {'%',{var_info,{x,1},[{fun_type,{t_cons,{t_tuple,3,true,#{}},nil}}]}}.
     {get_tuple_element,{x,0},1,{x,2}}.
-    {make_fun3,{f,246},0,0,{x,0},{list,[]}}.
-    {'%',{var_info,{x,0},[{fun_type,{t_cons,{t_tuple,3,true,#{}},nil}}]}}.
+    {move,{x,1},{x,0}}.
     {move,nil,{x,1}}.
     {line,[{location,"couch_key_tree.erl",231}]}.
     {call_ext,3,{extfunc,lists,foldl,3}}.
-    {test,is_nonempty_list,{f,244},[{x,0}]}.
+    {test,is_nonempty_list,{f,243},[{x,0}]}.
     {get_list,{x,0},{x,1},{x,2}}.
-    {test,is_nil,{f,244},[{x,2}]}.
+    {test,is_nil,{f,243},[{x,2}]}.
     {test_heap,3,2}.
     {put_tuple2,{x,1},{list,[{y,0},{x,1}]}}.
     {move,{y,1},{x,0}}.
@@ -3206,18 +3201,18 @@
     {get_tuple_element,{x,0},0,{x,0}}.
     {deallocate,0}.
     return.
-  {label,244}.
+  {label,243}.
     {line,[{location,"couch_key_tree.erl",231}]}.
     {badmatch,{x,0}}.
 
 
-{function, '-remove_leafs/2-fun-1-', 2, 246}.
-  {label,245}.
+{function, '-remove_leafs/2-fun-1-', 2, 245}.
+  {label,244}.
     {line,[{location,"couch_key_tree.erl",232}]}.
     {func_info,{atom,couch_key_tree},{atom,'-remove_leafs/2-fun-1-'},2}.
-  {label,246}.
-    {test,is_tuple,{f,245},[{x,0}]}.
-    {test,test_arity,{f,245},[{x,0},2]}.
+  {label,245}.
+    {test,is_tuple,{f,244},[{x,0}]}.
+    {test,test_arity,{f,244},[{x,0},2]}.
     {test_heap,6,2}.
     {get_tuple_element,{x,0},0,{x,2}}.
     {get_tuple_element,{x,0},1,{x,0}}.
@@ -3226,11 +3221,11 @@
     return.
 
 
-{function, '-remove_leafs/2-lc$^0/1-0-', 1, 248}.
-  {label,247}.
+{function, '-remove_leafs/2-lc$^0/1-0-', 1, 247}.
+  {label,246}.
     {line,[{location,"couch_key_tree.erl",225}]}.
     {func_info,{atom,couch_key_tree},{atom,'-remove_leafs/2-lc$^0/1-0-'},1}.
-  {label,248}.
+  {label,247}.
     {'%',
         {var_info,
             {x,0},
@@ -3239,17 +3234,17 @@
                      {t_tuple,2,true,
                          #{2 => {t_cons,{t_tuple,0,false,#{}},nil}}},
                      nil}}]}}.
-    {test,is_nonempty_list,{f,249},[{x,0}]}.
+    {test,is_nonempty_list,{f,248},[{x,0}]}.
     {get_list,{x,0},{x,1},{x,0}}.
     {get_tuple_element,{x,1},0,{x,2}}.
-    {get_tuple_element,{x,1},1,{x,1}}.
     {gc_bif,'+',{f,0},3,[{x,2},{integer,1}],{x,2}}.
+    {get_tuple_element,{x,1},1,{x,1}}.
     {gc_bif,length,{f,0},3,[{x,1}],{x,3}}.
     {gc_bif,'-',{f,0},4,[{x,2},{x,3}],{x,2}}.
     {allocate,2,3}.
     {move,{x,1},{y,0}}.
     {move,{x,2},{y,1}}.
-    {call,1,{f,248}}.
+    {call,1,{f,247}}.
     {'%',
         {var_info,
             {x,0},
@@ -3264,127 +3259,127 @@
     {put_list,{x,1},{x,0},{x,0}}.
     {deallocate,2}.
     return.
-  {label,249}.
+  {label,248}.
     return.
 
 
-{function, '-find_missing_simple/3-lc$^1/1-1-', 2, 251}.
-  {label,250}.
+{function, '-find_missing_simple/3-lc$^1/1-1-', 2, 250}.
+  {label,249}.
     {line,[{location,"couch_key_tree.erl",197}]}.
     {func_info,{atom,couch_key_tree},
                {atom,'-find_missing_simple/3-lc$^1/1-1-'},
                2}.
-  {label,251}.
+  {label,250}.
     {'%',{var_info,{x,0},[{type,{t_list,{t_tuple,2,true,#{}},nil}}]}}.
-    {test,is_nonempty_list,{f,253},[{x,0}]}.
+    {test,is_nonempty_list,{f,252},[{x,0}]}.
     {get_list,{x,0},{x,2},{x,0}}.
     {get_tuple_element,{x,2},0,{x,3}}.
-    {test,is_lt,{f,252},[{x,3},{x,1}]}.
+    {test,is_lt,{f,251},[{x,3},{x,1}]}.
     {allocate,1,3}.
     {move,{x,2},{y,0}}.
-    {call,2,{f,251}}.
+    {call,2,{f,250}}.
     {'%',{var_info,{x,0},[{type,{t_list,{t_tuple,2,true,#{}},nil}}]}}.
     {test_heap,2,1}.
     {put_list,{y,0},{x,0},{x,0}}.
     {deallocate,1}.
     return.
+  {label,251}.
+    {call_only,2,{f,250}}.
   {label,252}.
-    {call_only,2,{f,251}}.
-  {label,253}.
     return.
 
 
-{function, '-find_missing_simple/3-lc$^0/1-0-', 2, 255}.
-  {label,254}.
+{function, '-find_missing_simple/3-lc$^0/1-0-', 2, 254}.
+  {label,253}.
     {line,[{location,"couch_key_tree.erl",196}]}.
     {func_info,{atom,couch_key_tree},
                {atom,'-find_missing_simple/3-lc$^0/1-0-'},
                2}.
-  {label,255}.
+  {label,254}.
     {'%',{var_info,{x,0},[{type,{t_list,{t_tuple,2,true,#{}},nil}}]}}.
-    {test,is_nonempty_list,{f,257},[{x,0}]}.
+    {test,is_nonempty_list,{f,256},[{x,0}]}.
     {get_list,{x,0},{x,2},{x,0}}.
     {get_tuple_element,{x,2},0,{x,3}}.
-    {test,is_ge,{f,256},[{x,3},{x,1}]}.
+    {test,is_ge,{f,255},[{x,3},{x,1}]}.
     {allocate,1,3}.
     {move,{x,2},{y,0}}.
-    {call,2,{f,255}}.
+    {call,2,{f,254}}.
     {'%',{var_info,{x,0},[{type,{t_list,{t_tuple,2,true,#{}},nil}}]}}.
     {test_heap,2,1}.
     {put_list,{y,0},{x,0},{x,0}}.
     {deallocate,1}.
     return.
+  {label,255}.
+    {call_only,2,{f,254}}.
   {label,256}.
-    {call_only,2,{f,255}}.
-  {label,257}.
     return.
 
 
-{function, '-find_missing/2-lc$^1/1-1-', 2, 259}.
-  {label,258}.
+{function, '-find_missing/2-lc$^1/1-1-', 2, 258}.
+  {label,257}.
     {line,[{location,"couch_key_tree.erl",187}]}.
     {func_info,{atom,couch_key_tree},{atom,'-find_missing/2-lc$^1/1-1-'},2}.
-  {label,259}.
-    {test,is_nonempty_list,{f,261},[{x,0}]}.
+  {label,258}.
+    {test,is_nonempty_list,{f,260},[{x,0}]}.
     {get_list,{x,0},{x,2},{x,0}}.
-    {test,is_tuple,{f,260},[{x,2}]}.
-    {test,test_arity,{f,260},[{x,2},2]}.
+    {test,is_tuple,{f,259},[{x,2}]}.
+    {test,test_arity,{f,259},[{x,2},2]}.
     {get_tuple_element,{x,2},0,{x,3}}.
-    {test,is_lt,{f,260},[{x,3},{x,1}]}.
+    {test,is_lt,{f,259},[{x,3},{x,1}]}.
     {allocate,1,3}.
     {move,{x,2},{y,0}}.
-    {call,2,{f,259}}.
+    {call,2,{f,258}}.
     {'%',{var_info,{x,0},[{type,{t_list,{t_tuple,2,true,#{}},nil}}]}}.
     {test_heap,2,1}.
     {put_list,{y,0},{x,0},{x,0}}.
     {deallocate,1}.
     return.
+  {label,259}.
+    {call_only,2,{f,258}}.
   {label,260}.
-    {call_only,2,{f,259}}.
-  {label,261}.
-    {test,is_nil,{f,262},[{x,0}]}.
+    {test,is_nil,{f,261},[{x,0}]}.
     return.
-  {label,262}.
+  {label,261}.
     {test_heap,3,1}.
     {put_tuple2,{x,0},{list,[{atom,bad_generator},{x,0}]}}.
     {call_ext_only,1,{extfunc,erlang,error,1}}.
 
 
-{function, '-find_missing/2-lc$^0/1-0-', 2, 264}.
-  {label,263}.
+{function, '-find_missing/2-lc$^0/1-0-', 2, 263}.
+  {label,262}.
     {line,[{location,"couch_key_tree.erl",186}]}.
     {func_info,{atom,couch_key_tree},{atom,'-find_missing/2-lc$^0/1-0-'},2}.
-  {label,264}.
-    {test,is_nonempty_list,{f,266},[{x,0}]}.
+  {label,263}.
+    {test,is_nonempty_list,{f,265},[{x,0}]}.
     {get_list,{x,0},{x,2},{x,0}}.
-    {test,is_tuple,{f,265},[{x,2}]}.
-    {test,test_arity,{f,265},[{x,2},2]}.
+    {test,is_tuple,{f,264},[{x,2}]}.
+    {test,test_arity,{f,264},[{x,2},2]}.
     {get_tuple_element,{x,2},0,{x,3}}.
-    {test,is_ge,{f,265},[{x,3},{x,1}]}.
+    {test,is_ge,{f,264},[{x,3},{x,1}]}.
     {allocate,1,3}.
     {move,{x,2},{y,0}}.
-    {call,2,{f,264}}.
+    {call,2,{f,263}}.
     {'%',{var_info,{x,0},[{type,{t_list,{t_tuple,2,true,#{}},nil}}]}}.
     {test_heap,2,1}.
     {put_list,{y,0},{x,0},{x,0}}.
     {deallocate,1}.
     return.
+  {label,264}.
+    {call_only,2,{f,263}}.
   {label,265}.
-    {call_only,2,{f,264}}.
-  {label,266}.
-    {test,is_nil,{f,267},[{x,0}]}.
+    {test,is_nil,{f,266},[{x,0}]}.
     return.
-  {label,267}.
+  {label,266}.
     {test_heap,3,1}.
     {put_tuple2,{x,0},{list,[{atom,bad_generator},{x,0}]}}.
     {call_ext_only,1,{extfunc,erlang,error,1}}.
 
 
-{function, '-multi_merge/2-fun-0-', 2, 269}.
-  {label,268}.
+{function, '-multi_merge/2-fun-0-', 2, 268}.
+  {label,267}.
     {line,[{location,"couch_key_tree.erl",46}]}.
     {func_info,{atom,couch_key_tree},{atom,'-multi_merge/2-fun-0-'},2}.
-  {label,269}.
+  {label,268}.
     {allocate,0,2}.
     {swap,{x,0},{x,1}}.
     {line,[{location,"couch_key_tree.erl",47}]}.