fast-vs-slow.diff

--- func-no-opt.S	2022-03-21 15:42:16.000000000 -0500
+++ func-opt.S	2022-03-21 15:42:34.000000000 -0500
@@ -14,68 +14,60 @@
   {label,2}.
     {test,is_tuple,{f,6},[{x,1}]}.
     {test,test_arity,{f,6},[{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}}.
     {line,[{location,"func.erl",8}]}.
-    {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}}.
+    {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_ext,4,{extfunc,couch_key_tree,stem_tree,4}}.
+    {move,{x,0},{y,1}}.
     {test,is_tuple,{f,5},[{x,0}]}.
-    {select_tuple_arity,{x,0},{f,5},{list,[3,{f,4},4,{f,3}]}}.
+    {get_tuple_element,{y,2},1,{x,0}}.
+    {get_tuple_element,{y,2},2,{y,0}}.
+    {get_tuple_element,{y,2},3,{y,2}}.
+    {select_tuple_arity,{y,1},{f,5},{list,[3,{f,4},4,{f,3}]}}.
   {label,3}.
-    {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,1},1,{x,1}}.
+    {swap,{x,0},{x,1}}.
     {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,1},2,{x,1}}.
+    {put_list,{x,1},{y,0},{y,0}}.
+    {get_tuple_element,{y,1},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,"func.erl",12}]}.
     {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,1},0,{x,1}}.
+    {put_tuple2,{x,0},{list,[{x,1},{y,2},{y,0},{x,0}]}}.
+    {deallocate,3}.
     return.
   {label,4}.
-    {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}]}}.
+    {get_tuple_element,{y,1},1,{x,1}}.
+    {swap,{x,0},{x,1}}.
     {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,1},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,"func.erl",16}]}.
     {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,1},0,{x,1}}.
+    {put_tuple2,{x,0},{list,[{x,1},{y,2},{y,0},{x,0}]}}.
+    {deallocate,3}.
     return.
   {label,5}.
     {line,[{location,"func.erl",8}]}.
-    {case_end,{x,0}}.
+    {case_end,{y,1}}.
   {label,6}.
     {line,[{location,"func.erl",7}]}.
     {badmatch,{x,1}}.