anchor.diff:      Float + {a,b}.
   
   select_val(Config) when is_list(Config) ->
  -    ?line zero = do_select_val(0),
  -    ?line big = do_select_val(1 bsl 64),
  -    ?line integer = do_select_val(42),
  +    zero = do_select_val(0),
  +    big = do_select_val(1 bsl 64),
  +    integer = do_select_val(42),
       ok.
   
   do_select_val(X) ->
  
positive.code: %% Test three high register numbers in a put_list instruction
  %% (to test whether packing works properly).
  packed_registers(Config) when is_list(Config) ->
      ?line PrivDir = ?config(priv_dir, Config),
      ?line Mod = packed_regs,
      ?line Name = filename:join(PrivDir, atom_to_list(Mod) ++ ".erl"),
  
      %% Generate a module which generates a list of tuples.
      %% put_list(A) -> [{A, 600}, {A, 999}, ... {A, 0}].
      ?line Code = gen_packed_regs(600, ["-module("++atom_to_list(Mod)++").\n",
  				       "-export([put_list/1]).\n",
  				       "put_list(A) ->\n["]),
      ?line ok = file:write_file(Name, Code),
  
      %% Compile the module.
      ?line io:format("Compiling: ~s\n", [Name]),
      ?line CompRc = compile:file(Name, [{outdir, PrivDir}, report]),
      ?line io:format("Result: ~p\n",[CompRc]),
      ?line {ok, Mod} = CompRc,
  
      %% Load it.
      ?line io:format("Loading...\n",[]),
      ?line LoadRc = code:load_abs(filename:join(PrivDir, atom_to_list(Mod))),
      ?line {module,_Module} = LoadRc,
  
      %% Call it and verify result.
      ?line Term = {a, b},
      ?line L = Mod:put_list(Term),
      ?line verify_packed_regs(L, Term, 600),
      ok.
  
  gen_packed_regs(0, Acc) ->
  
negative.code:      {<<>>,1},{<<>>,1},{<<>>,1},{<<>>,1},{<<>>,1},{<<>>,1},{<<>>,1},{<<>>,1}].
  
  heap_sizes(Config) when is_list(Config) ->
      Sizes = erlang:system_info(heap_sizes),
      io:format("~p heap sizes\n", [length(Sizes)]),
      io:format("~p\n", [Sizes]),
  
      %% Verify that heap sizes increase monotonically.
      Largest = lists:foldl(fun(E, P) when is_integer(P), E > P -> E;
  				   (E, []) -> E
  				end, [], Sizes),
  
  