%% -*- erlang-indent-level: 2 -*-
%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2001-2010. All Rights Reserved.
%%
%% The contents of this file are subject to the Erlang Public License,
%% Version 1.1, (the "License"); you may not use this file except in
%% compliance with the License. You should have received a copy of the
%% Erlang Public License along with this software. If not, it can be
%% retrieved online at http://www.erlang.org/.
%%
%% Software distributed under the License is distributed on an "AS IS"
%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
%% the License for the specific language governing rights and limitations
%% under the License.
%%
%% %CopyrightEnd%
%%
%%=======================================================================
%% File        : hipe_beam_to_icode.erl
%% Author      : Kostis Sagonas
%% Description : Translates symbolic BEAM code to Icode
%%=======================================================================
%% @doc
%%    This file translates symbolic BEAM code to Icode which is HiPE's
%%    intermediate code representation.  Either the code of an entire
%%    module, or the code of a specified function can be translated.
%% @end
%%=======================================================================

-module(hipe_beam_to_icode).

-export([module/2, mfa/3]).

%%-----------------------------------------------------------------------

%% Uncomment the following lines to turn on debugging for this module
%% or comment them to it turn off.  Debug-level 6 inserts a print in
%% each compiled function.
%%
%%-ifndef(DEBUG).
%%-define(DEBUG,6).
%%-endif.

-include("../main/hipe.hrl").
-include("hipe_icode.hrl").
-include("hipe_icode_primops.hrl").
-include("../../compiler/src/beam_disasm.hrl").

-define(no_debug_msg(Str,Xs),ok).
%%-define(no_debug_msg(Str,Xs),msg(Str,Xs)).

-define(mk_debugcode(MFA, Env, Code),
	case MFA of
	  {io,_,_} ->
	    %% We do not want to loop infinitely if we are compiling
	    %% the module io.
	    {Code,Env};
	  {M,F,A} ->
	    MFAVar = mk_var(new),
	    StringVar = mk_var(new),
	    Ignore = mk_var(new),
	    MkMfa = hipe_icode:mk_move(MFAVar,hipe_icode:mk_const([MFA])),
	    MkString = hipe_icode:mk_move(StringVar,
					  hipe_icode:mk_const(
					    atom_to_list(M) ++ ":" ++ atom_to_list(F) ++"/"++ integer_to_list(A) ++ 
					    " Native enter fun ~w\n")),
	    Call =
	      hipe_icode:mk_call([Ignore],io,format,[StringVar,MFAVar],remote),
	    {[MkMfa,MkString,Call | Code], Env}
	end).

%%-----------------------------------------------------------------------
%% Exported types
%%-----------------------------------------------------------------------

-type hipe_beam_to_icode_ret() :: [{mfa(),#icode{}}].


%%-----------------------------------------------------------------------
%% Internal data structures
%%-----------------------------------------------------------------------

-record(beam_const, {value :: simple_const()}). % defined in hipe_icode.hrl

-record(closure_info, {mfa :: mfa(), arity :: arity(), fv_arity :: arity()}).

-record(environment, {mfa :: mfa(), entry :: non_neg_integer()}).


%%-----------------------------------------------------------------------
%% @doc
%% Translates the code of a whole module into Icode.
%%   Returns a tuple whose first argument is a list of {{M,F,A}, ICode} 
%%   pairs, and its second argument is the list of HiPE compiler options.
%% @end
%%-----------------------------------------------------------------------

-spec module([#function{}], comp_options()) -> hipe_beam_to_icode_ret().

module(BeamFuns, Options) ->
  BeamCode0 = [beam_disasm:function__code(F) || F <- BeamFuns],
  {ModCode, ClosureInfo} = preprocess_code(BeamCode0),
  pp_beam(ModCode, Options),
  [trans_beam_function_chunk(FunCode, ClosureInfo) || FunCode <- ModCode].

trans_beam_function_chunk(FunBeamCode, ClosureInfo) ->
  {M,F,A} = MFA = find_mfa(FunBeamCode),
  Icode = trans_mfa_code(M,F,A, FunBeamCode, ClosureInfo),
  {MFA,Icode}.

%%-----------------------------------------------------------------------
%% @doc
%% Translates the BEAM code of a single function into Icode.
%%   Returns a tuple whose first argument is list of {{M,F,A}, ICode}
%%   pairs, where the first entry is that of the given MFA, and the
%%   following (in undefined order) are those of the funs that are
%%   defined in the function, and recursively, in the funs.  The
%%   second argument of the tuple is the HiPE compiler options
%%   contained in the file.
%% @end
%%-----------------------------------------------------------------------

-spec mfa(list(), mfa(), comp_options()) -> hipe_beam_to_icode_ret().

mfa(BeamFuns, {M,F,A} = MFA, Options)
  when is_atom(M), is_atom(F), is_integer(A) ->
  BeamCode0 = [beam_disasm:function__code(Fn) || Fn <- BeamFuns],
  {ModCode, ClosureInfo} = preprocess_code(BeamCode0),
  mfa_loop([MFA], [], sets:new(), ModCode, ClosureInfo, Options).

mfa_loop([{M,F,A} = MFA | MFAs], Acc, Seen, ModCode, ClosureInfo,
	 Options) when is_atom(M), is_atom(F), is_integer(A) ->
  case sets:is_element(MFA, Seen) of
    true ->
      mfa_loop(MFAs, Acc, Seen, ModCode, ClosureInfo, Options);
    false ->
      {Icode, FunMFAs} = mfa_get(M, F, A, ModCode, ClosureInfo, Options),
      mfa_loop(FunMFAs ++ MFAs, [{MFA, Icode} | Acc],
	       sets:add_element(MFA, Seen),
	       ModCode, ClosureInfo, Options)
  end;
mfa_loop([], Acc, _, _, _, _) ->
  lists:reverse(Acc).

mfa_get(M, F, A, ModCode, ClosureInfo, Options) ->
  BeamCode = get_fun(ModCode, M,F,A),
  pp_beam([BeamCode], Options),  % cheat by using a list
  Icode = trans_mfa_code(M,F,A, BeamCode, ClosureInfo),
  FunMFAs = get_fun_mfas(BeamCode),
  {Icode, FunMFAs}.

get_fun_mfas([{patched_make_fun,{M,F,A} = MFA,_,_,_}|BeamCode])
  when is_atom(M), is_atom(F), is_integer(A) ->
  [MFA|get_fun_mfas(BeamCode)];
get_fun_mfas([_|BeamCode]) ->
  get_fun_mfas(BeamCode);
get_fun_mfas([]) ->
  [].

%%-----------------------------------------------------------------------
%% The main translation function.
%%-----------------------------------------------------------------------

trans_mfa_code(M,F,A, FunBeamCode, ClosureInfo) ->
  ?no_debug_msg("disassembling: {~p,~p,~p} ...", [M,F,A]),
  hipe_gensym:init(icode),
  %% Extract the function arguments
  FunArgs = extract_fun_args(A),
  %% Record the function arguments
  FunLbl = mk_label(new),
  Env1 = env__mk_env(M, F, A, hipe_icode:label_name(FunLbl)),
  Code1 = lists:flatten(trans_fun(FunBeamCode,Env1)),
  Code2 = fix_fallthroughs(fix_catches(Code1)),
  MFA = {M,F,A},
  %% Debug code
  ?IF_DEBUG_LEVEL(5,
		  {Code3,_Env3} = ?mk_debugcode(MFA, Env2, Code2),
		  {Code3,_Env3} = {Code2,Env1}),
  %% For stack optimization
  Leafness = leafness(Code3),
  IsLeaf = is_leaf_code(Leafness),
  Code4 =
    [FunLbl |
     case needs_redtest(Leafness) of
       false -> Code3;
       true -> [mk_redtest()|Code3]
     end],
  IsClosure = get_closure_info(MFA, ClosureInfo) =/= not_a_closure,
  Code5 = hipe_icode:mk_icode(MFA, FunArgs, IsClosure, IsLeaf,
			      remove_dead_code(Code4),
			      hipe_gensym:var_range(icode),
			      hipe_gensym:label_range(icode)),
  Icode = %% If this function is the code for a closure ...
    case get_closure_info(MFA, ClosureInfo) of
      not_a_closure -> Code5;
      CI -> %% ... then patch the code to 
	%% get the free_vars from the closure
	patch_closure_entry(Code5, CI)
    end,
  ?no_debug_msg("ok~n", []),
  Icode.

mk_redtest() -> hipe_icode:mk_primop([], redtest, []).

leafness(Is) -> % -> true, selfrec, or false
  leafness(Is, true).

leafness([], Leafness) ->
  Leafness;
leafness([I|Is], Leafness) ->
  case I of
    #icode_comment{} ->
      %% BEAM self-tailcalls become gotos, but they leave
      %% a trace behind in comments. Check those to ensure
      %% that the computed leafness is correct. Needed to
      %% prevent redtest elimination in those cases.
      NewLeafness =
	case hipe_icode:comment_text(I) of
	  'tail_recursive' -> selfrec;		% call_last to selfrec
	  'self_tail_recursive' -> selfrec;	% call_only to selfrec
	  _ -> Leafness
	end,
      leafness(Is, NewLeafness);
    #icode_call{} ->
      case hipe_icode:call_type(I) of
	'primop' -> 
	  case hipe_icode:call_fun(I) of
	    call_fun -> false;		% Calls closure
	    enter_fun -> false;		% Calls closure
	    #apply_N{} -> false;
	    _ -> leafness(Is, Leafness)	% Other primop calls are ok
	  end;
	T when T =:= 'local' orelse T =:= 'remote' ->
	  {M,F,A} = hipe_icode:call_fun(I),
	  case erlang:is_builtin(M, F, A) of
	    true -> leafness(Is, Leafness);
	    false -> false
	  end
      end;
    #icode_enter{} ->
      case hipe_icode:enter_type(I) of
	'primop' ->
	  case hipe_icode:enter_fun(I) of
	    enter_fun -> false;
	    #apply_N{} -> false;
	    _ ->
	      %% All primops should be ok except those excluded above,
	      %% except we don't actually tailcall them...
	      io:format("leafness: unexpected enter to primop ~w\n", [I]),
	      true
	  end;
	T when T =:= 'local' orelse T =:= 'remote' ->
	  {M,F,A} = hipe_icode:enter_fun(I),
	  case erlang:is_builtin(M, F, A) of
	    true -> leafness(Is, Leafness);
	    _ -> false
	  end
      end;
    _ -> leafness(Is, Leafness)
  end.

%% XXX: this old stuff is passed around but essentially unused
is_leaf_code(Leafness) ->
  case Leafness of
    true -> true;
    selfrec -> true;
    false -> false
  end.

needs_redtest(Leafness) ->
  case Leafness of
    true -> false;
    selfrec -> true;
    false -> true
  end.

%%-----------------------------------------------------------------------
%% The main translation switch.
%%-----------------------------------------------------------------------

%%--- label & func_info combo ---
trans_fun([{label,B},{label,_},
	   {func_info,M,F,A},{label,L}|Instructions], Env) ->
  trans_fun([{label,B},{func_info,M,F,A},{label,L}|Instructions], Env);
trans_fun([{label,B},
	   {func_info,{atom,_M},{atom,_F},_A},
	   {label,L}|Instructions], Env) ->
  %% Emit code to handle function_clause errors.  The BEAM test instructions
  %% branch to this label if they fail during function clause selection.
  %% Obviously, we must goto past this error point on normal entry.
  Begin = mk_label(B),
  V = mk_var(new),
  EntryPt = mk_label(L),
  Goto = hipe_icode:mk_goto(hipe_icode:label_name(EntryPt)),
  Mov = hipe_icode:mk_move(V, hipe_icode:mk_const(function_clause)),
  Fail = hipe_icode:mk_fail([V],error),
  [Goto, Begin, Mov, Fail, EntryPt | trans_fun(Instructions, Env)];
%%--- label ---
trans_fun([{label,L1},{label,L2}|Instructions], Env) ->
  %% Old BEAM code can have two consecutive labels.
  Lab1 = mk_label(L1),
  Lab2 = mk_label(L2),
  Goto = hipe_icode:mk_goto(map_label(L2)),
  [Lab1, Goto, Lab2 | trans_fun(Instructions, Env)];
trans_fun([{label,L}|Instructions], Env) ->
  [mk_label(L) | trans_fun(Instructions, Env)];
%%--- int_code_end --- SHOULD NEVER OCCUR HERE
%%--- call ---
trans_fun([{call,_N,{_M,_F,A}=MFA}|Instructions], Env) ->
  Args = extract_fun_args(A),
  Dst = [mk_var({r,0})],
  I = trans_call(MFA, Dst, Args, local),
  [I | trans_fun(Instructions, Env)];
%%--- call_last ---
%% Differs from call_only in that it deallocates the environment
trans_fun([{call_last,_N,{_M,_F,A}=MFA,_}|Instructions], Env) ->
  %% IS IT OK TO IGNORE LAST ARG ??
  ?no_debug_msg("  translating call_last: ~p ...~n", [Env]),
  case env__get_mfa(Env) of
    MFA ->
      %% Does this case really happen, or is it covered by call_only?
      Entry = env__get_entry(Env),
      [hipe_icode:mk_comment('tail_recursive'), % needed by leafness/2
       hipe_icode:mk_goto(Entry) | trans_fun(Instructions,Env)];
    _ ->
      Args = extract_fun_args(A),
      I = trans_enter(MFA, Args, local),
      [I | trans_fun(Instructions, Env)]
  end;
%%--- call_only ---
%% Used when the body contains only one call in which case 
%% an environment is not needed/created.
trans_fun([{call_only,_N,{_M,_F,A}=MFA}|Instructions], Env) ->
  ?no_debug_msg("  translating call_only: ~p ...~n", [Env]),
  case env__get_mfa(Env) of
    MFA ->
      Entry = env__get_entry(Env),
      [hipe_icode:mk_comment('self_tail_recursive'), % needed by leafness/2
       hipe_icode:mk_goto(Entry) | trans_fun(Instructions,Env)];
    _ ->
      Args = extract_fun_args(A),
      I = trans_enter(MFA,Args,local),
      [I |  trans_fun(Instructions,Env)]
  end;
%%--- call_ext ---
trans_fun([{call_ext,_N,{extfunc,M,F,A}}|Instructions], Env) ->
  Args = extract_fun_args(A),
  Dst = [mk_var({r,0})],
  I = trans_call({M,F,A},Dst,Args,remote),
  [hipe_icode:mk_comment('call_ext'),I | trans_fun(Instructions,Env)];
%%--- call_ext_last ---
trans_fun([{call_ext_last,_N,{extfunc,M,F,A},_}|Instructions], Env) ->
  %% IS IT OK TO IGNORE LAST ARG ??
  Args = extract_fun_args(A),
  %% Dst = [mk_var({r,0})],
  I = trans_enter({M,F,A},Args,remote),
  [hipe_icode:mk_comment('call_ext_last'), I | trans_fun(Instructions,Env)];
%%--- bif0 ---
trans_fun([{bif,BifName,nofail,[],Reg}|Instructions], Env) ->
  BifInst = trans_bif0(BifName,Reg),
  [hipe_icode:mk_comment({bif0,BifName}),BifInst|trans_fun(Instructions,Env)];
%%--- bif1 ---
trans_fun([{bif,BifName,{f,Lbl},[_] = Args,Reg}|Instructions], Env) ->
  {BifInsts,Env1} = trans_bif(1,BifName,Lbl,Args,Reg,Env),
  [hipe_icode:mk_comment({bif1,BifName})|BifInsts] ++ trans_fun(Instructions,Env1);
%%--- bif2 ---
trans_fun([{bif,BifName,{f,Lbl},[_,_] = Args,Reg}|Instructions], Env) ->
  {BifInsts,Env1} = trans_bif(2,BifName,Lbl,Args,Reg,Env),
  [hipe_icode:mk_comment({bif2,BifName})|BifInsts] ++ trans_fun(Instructions,Env1);
%%--- allocate
trans_fun([{allocate,StackSlots,_}|Instructions], Env) ->
  trans_allocate(StackSlots) ++ trans_fun(Instructions,Env);
%%--- allocate_heap
trans_fun([{allocate_heap,StackSlots,_,_}|Instructions], Env) ->
  trans_allocate(StackSlots) ++ trans_fun(Instructions,Env);
%%--- allocate_zero
trans_fun([{allocate_zero,StackSlots,_}|Instructions], Env) ->
  trans_allocate(StackSlots) ++ trans_fun(Instructions,Env);
%%--- allocate_heap_zero
trans_fun([{allocate_heap_zero,StackSlots,_,_}|Instructions], Env) ->
  trans_allocate(StackSlots) ++ trans_fun(Instructions,Env);
%%--- test_heap --- IGNORED ON PURPOSE
trans_fun([{test_heap,_,_}|Instructions], Env) ->
  trans_fun(Instructions,Env);
%%--- init --- IGNORED - CORRECT??
trans_fun([{init,_}|Instructions], Env) ->
  trans_fun(Instructions,Env);
%%--- deallocate --- IGNORED ON PURPOSE
trans_fun([{deallocate,_}|Instructions], Env) ->
  trans_fun(Instructions,Env);
%%--- return ---
trans_fun([return|Instructions], Env) ->
  [hipe_icode:mk_return([mk_var({r,0})]) | trans_fun(Instructions,Env)];
%%--- send ---
trans_fun([send|Instructions], Env) ->
  I = hipe_icode:mk_call([mk_var({r,0})], erlang, send,
			 [mk_var({x,0}),mk_var({x,1})], remote),
  [I | trans_fun(Instructions,Env)];
%%--- remove_message ---
trans_fun([remove_message|Instructions], Env) ->
  [hipe_icode:mk_primop([],select_msg,[]) | trans_fun(Instructions,Env)];
%%--- timeout --- 
trans_fun([timeout|Instructions], Env) ->
  [hipe_icode:mk_primop([],clear_timeout,[]) | trans_fun(Instructions,Env)];
%%--- loop_rec ---
trans_fun([{loop_rec,{_,Lbl},Reg}|Instructions], Env) ->
  {Movs,[Temp],Env1} = get_constants_in_temps([Reg],Env),
  GotitLbl = mk_label(new),
  ChkGetMsg = hipe_icode:mk_primop([Temp],check_get_msg,[],
				   hipe_icode:label_name(GotitLbl),
				   map_label(Lbl)),
  Movs ++ [ChkGetMsg, GotitLbl | trans_fun(Instructions,Env1)];
%%--- loop_rec_end ---
trans_fun([{loop_rec_end,{_,Lbl}}|Instructions], Env) ->
  Loop = hipe_icode:mk_goto(map_label(Lbl)),
  [hipe_icode:mk_primop([],next_msg,[]), Loop | trans_fun(Instructions,Env)];
%%--- wait ---
trans_fun([{wait,{_,Lbl}}|Instructions], Env) ->
  Susp = hipe_icode:mk_primop([],suspend_msg,[]),
  Loop = hipe_icode:mk_goto(map_label(Lbl)),
  [Susp, Loop | trans_fun(Instructions,Env)];
%%--- wait_timeout ---
trans_fun([{wait_timeout,{_,Lbl},Reg}|Instructions], Env) ->
  {Movs,[_]=Temps,Env1} = get_constants_in_temps([Reg],Env),
  SetTmout = hipe_icode:mk_primop([],set_timeout,Temps),
  DoneLbl = mk_label(new),
  SuspTmout = hipe_icode:mk_if(suspend_msg_timeout,[],
			       map_label(Lbl),hipe_icode:label_name(DoneLbl)),
  Movs ++ [SetTmout, SuspTmout, DoneLbl | trans_fun(Instructions,Env1)];
%%--- recv_mark/1 & recv_set/1 ---  XXX: Handle better??
trans_fun([{recv_mark,{f,_}}|Instructions], Env) ->
  trans_fun(Instructions,Env);
trans_fun([{recv_set,{f,_}}|Instructions], Env) ->
  trans_fun(Instructions,Env);
%%--------------------------------------------------------------------
%%--- Translation of arithmetics {bif,ArithOp, ...} ---
%%--------------------------------------------------------------------
trans_fun([{arithbif,ArithOp,{f,L},SrcRs,DstR}|Instructions], Env) ->
  {ICode,NewEnv} = trans_arith(ArithOp,SrcRs,DstR,L,Env),
  ICode ++ trans_fun(Instructions,NewEnv);
%%--------------------------------------------------------------------
%%--- Translation of arithmetic tests {test,is_ARITHTEST, ...} ---
%%--------------------------------------------------------------------
%%--- is_lt ---
trans_fun([{test,is_lt,{f,Lbl},[Arg1,Arg2]}|Instructions], Env) ->
  {ICode,Env1} = trans_test_guard('<',Lbl,Arg1,Arg2,Env),
  ICode ++ trans_fun(Instructions,Env1);
%%--- is_ge ---
trans_fun([{test,is_ge,{f,Lbl},[Arg1,Arg2]}|Instructions], Env) ->
  {ICode,Env1} = trans_test_guard('>=',Lbl,Arg1,Arg2,Env),
  ICode ++ trans_fun(Instructions,Env1);
%%--- is_eq ---
trans_fun([{test,is_eq,{f,Lbl},[Arg1,Arg2]}|Instructions], Env) ->
  {ICode,Env1} = trans_is_eq(Lbl,Arg1,Arg2,Env),
  ICode ++ trans_fun(Instructions,Env1);
%%--- is_ne ---
trans_fun([{test,is_ne,{f,Lbl},[Arg1,Arg2]}|Instructions], Env) ->
  {ICode,Env1} = trans_is_ne(Lbl,Arg1,Arg2,Env),
  ICode ++ trans_fun(Instructions,Env1);
%%--- is_eq_exact ---
trans_fun([{test,is_eq_exact,{f,Lbl},[Arg1,Arg2]}|Instructions], Env) ->
  {ICode,Env1} = trans_is_eq_exact(Lbl,Arg1,Arg2,Env),
  ICode ++ trans_fun(Instructions,Env1);
%%--- is_ne_exact ---
trans_fun([{test,is_ne_exact,{f,Lbl},[Arg1,Arg2]}|Instructions], Env) ->
  {ICode,Env1} = trans_is_ne_exact(Lbl,Arg1,Arg2,Env),
  ICode ++ trans_fun(Instructions,Env1);
%%--------------------------------------------------------------------
%%--- Translation of type tests {test,is_TYPE, ...} ---
%%--------------------------------------------------------------------
%%--- is_integer ---
trans_fun([{test,is_integer,{f,Lbl},[Arg]}|Instructions], Env) ->
  {Code,Env1} = trans_type_test(integer,Lbl,Arg,Env),
  [Code | trans_fun(Instructions,Env1)];
%%--- is_float ---
trans_fun([{test,is_float,{f,Lbl},[Arg]}|Instructions], Env) ->
  {Code,Env1} = trans_type_test(float,Lbl,Arg,Env),
  [Code | trans_fun(Instructions,Env1)];
%%--- is_number ---
trans_fun([{test,is_number,{f,Lbl},[Arg]}|Instructions], Env) ->
  {Code,Env1} = trans_type_test(number,Lbl,Arg,Env),
  [Code | trans_fun(Instructions,Env1)];
%%--- is_atom ---
trans_fun([{test,is_atom,{f,Lbl},[Arg]}|Instructions], Env) ->
  {Code,Env1} = trans_type_test(atom,Lbl,Arg,Env),
  [Code | trans_fun(Instructions,Env1)];
%%--- is_pid ---
trans_fun([{test,is_pid,{f,Lbl},[Arg]}|Instructions], Env) ->
  {Code,Env1} = trans_type_test(pid,Lbl,Arg,Env),
  [Code | trans_fun(Instructions,Env1)];
%%--- is_ref ---
trans_fun([{test,is_reference,{f,Lbl},[Arg]}|Instructions], Env) ->
  {Code,Env1} = trans_type_test(reference,Lbl,Arg,Env),
  [Code | trans_fun(Instructions,Env1)];
%%--- is_port ---
trans_fun([{test,is_port,{f,Lbl},[Arg]}|Instructions], Env) ->
  {Code,Env1} = trans_type_test(port,Lbl,Arg,Env),
  [Code | trans_fun(Instructions,Env1)];
%%--- is_nil ---
trans_fun([{test,is_nil,{f,Lbl},[Arg]}|Instructions], Env) ->
  {Code,Env1} = trans_type_test(nil,Lbl,Arg,Env),
  [Code | trans_fun(Instructions,Env1)];
%%--- is_binary ---
trans_fun([{test,is_binary,{f,Lbl},[Arg]}|Instructions], Env) ->
  {Code,Env1} = trans_type_test(binary,Lbl,Arg,Env),
  [Code | trans_fun(Instructions,Env1)];
%%--- is_constant ---
trans_fun([{test,is_constant,{f,Lbl},[Arg]}|Instructions], Env) ->
  {Code,Env1} = trans_type_test(constant,Lbl,Arg,Env),
  [Code | trans_fun(Instructions,Env1)];
%%--- is_list ---
trans_fun([{test,is_list,{f,Lbl},[Arg]}|Instructions], Env) ->
  {Code,Env1} = trans_type_test(list,Lbl,Arg,Env),
  [Code | trans_fun(Instructions,Env1)];
%%--- is_nonempty_list ---
trans_fun([{test,is_nonempty_list,{f,Lbl},[Arg]}|Instructions], Env) ->
  {Code,Env1} = trans_type_test(cons,Lbl,Arg,Env),
  [Code | trans_fun(Instructions,Env1)];
%%--- is_tuple ---
trans_fun([{test,is_tuple,{f,_Lbl}=FLbl,[Xreg]},
	   {test,test_arity,FLbl,[Xreg,_]=Args}|Instructions], Env) ->
  trans_fun([{test,test_arity,FLbl,Args}|Instructions],Env);
trans_fun([{test,is_tuple,{_,Lbl},[Arg]}|Instructions], Env) ->
  {Code,Env1} = trans_type_test(tuple,Lbl,Arg,Env),
  [Code | trans_fun(Instructions,Env1)];
%%--- test_arity ---
trans_fun([{test,test_arity,{f,Lbl},[Reg,N]}|Instructions], Env) ->
  True = mk_label(new),
  I = hipe_icode:mk_type([trans_arg(Reg)],{tuple,N}, 
			 hipe_icode:label_name(True),map_label(Lbl)),
  [I,True | trans_fun(Instructions,Env)];
%%--------------------------------------------------------------------
%%--- select_val ---
trans_fun([{select_val,Reg,{f,Lbl},{list,Cases}}|Instructions], Env) ->
  {SwVar,CasePairs} = trans_select_stuff(Reg,Cases),
  Len = length(CasePairs),
  I = hipe_icode:mk_switch_val(SwVar,map_label(Lbl),Len,CasePairs),
  ?no_debug_msg("switch_val instr is ~p~n",[I]),
  [I | trans_fun(Instructions,Env)];
%%--- select_tuple_arity ---
trans_fun([{select_tuple_arity,Reg,{f,Lbl},{list,Cases}}|Instructions],Env) ->
  {SwVar,CasePairs} = trans_select_stuff(Reg,Cases),
  Len = length(CasePairs),
  I = hipe_icode:mk_switch_tuple_arity(SwVar,map_label(Lbl),Len,CasePairs),
  ?no_debug_msg("switch_tuple_arity instr is ~p~n",[I]),
  [I | trans_fun(Instructions,Env)];    
%%--- jump ---
trans_fun([{jump,{_,L}}|Instructions], Env) ->
  Label = mk_label(L),
  I = hipe_icode:mk_goto(hipe_icode:label_name(Label)),
  [I | trans_fun(Instructions,Env)];
%%--- move ---
trans_fun([{move,Src,Dst}|Instructions], Env) ->
  Dst1 = mk_var(Dst),
  Src1 = trans_arg(Src),
  [hipe_icode:mk_move(Dst1,Src1) | trans_fun(Instructions,Env)];
%%--- catch --- ITS PROCESSING IS POSTPONED
trans_fun([{'catch',N,{_,EndLabel}}|Instructions], Env) ->
  NewContLbl = mk_label(new),
  [{'catch',N,EndLabel},NewContLbl | trans_fun(Instructions,Env)];
%%--- catch_end --- ITS PROCESSING IS POSTPONED
trans_fun([{catch_end,_N}=I|Instructions], Env) ->
  [I | trans_fun(Instructions,Env)];
%%--- try --- ITS PROCESSING IS POSTPONED
trans_fun([{'try',N,{_,EndLabel}}|Instructions], Env) ->
  NewContLbl = mk_label(new),
  [{'try',N,EndLabel},NewContLbl | trans_fun(Instructions,Env)];
%%--- try_end ---
trans_fun([{try_end,_N}|Instructions], Env) ->
  [hipe_icode:mk_end_try() | trans_fun(Instructions,Env)];
%%--- try_case --- ITS PROCESSING IS POSTPONED
trans_fun([{try_case,_N}=I|Instructions], Env) ->
  [I | trans_fun(Instructions,Env)];
%%--- try_case_end ---
trans_fun([{try_case_end,Arg}|Instructions], Env) ->
  BadArg = trans_arg(Arg),
  ErrVar = mk_var(new),
  Vs = [mk_var(new)],
  Atom = hipe_icode:mk_move(ErrVar,hipe_icode:mk_const(try_clause)),
  Tuple = hipe_icode:mk_primop(Vs,mktuple,[ErrVar,BadArg]),
  Fail = hipe_icode:mk_fail(Vs,error),
  [Atom,Tuple,Fail | trans_fun(Instructions,Env)];
%%--- raise ---
trans_fun([{raise,{f,0},[Reg1,Reg2],{x,0}}|Instructions], Env) ->
  V1 = trans_arg(Reg1),
  V2 = trans_arg(Reg2),
  Fail = hipe_icode:mk_fail([V1,V2],rethrow),
  [Fail | trans_fun(Instructions,Env)];
%%--- get_list ---
trans_fun([{get_list,List,Head,Tail}|Instructions], Env) ->
  TransList = [trans_arg(List)],
  I1 = hipe_icode:mk_primop([mk_var(Head)],unsafe_hd,TransList),
  I2 = hipe_icode:mk_primop([mk_var(Tail)],unsafe_tl,TransList),
  %% Handle the cases where the dest overwrites the src!!
  if 
    Head =/= List ->
      [I1, I2 | trans_fun(Instructions,Env)];
    Tail =/= List ->
      [I2, I1 | trans_fun(Instructions,Env)];
    true ->
      %% XXX: We should take care of this case!!!!!
      ?error_msg("hd and tl regs identical in get_list~n",[]),
      erlang:error(not_handled)
  end;
%%--- get_tuple_element ---
trans_fun([{get_tuple_element,Xreg,Index,Dst}|Instructions], Env) ->
  I = hipe_icode:mk_primop([mk_var(Dst)],
			   #unsafe_element{index=Index+1},
			   [trans_arg(Xreg)]),
  [I | trans_fun(Instructions,Env)];
%%--- set_tuple_element ---
trans_fun([{set_tuple_element,Elem,Tuple,Index}|Instructions], Env) ->
  Elem1 = trans_arg(Elem),
  I = hipe_icode:mk_primop([mk_var(Tuple)],
			   #unsafe_update_element{index=Index+1},
			   [mk_var(Tuple),Elem1]),
  [I | trans_fun(Instructions,Env)];
%%--- put_string ---
trans_fun([{put_string,_Len,String,Dst}|Instructions], Env) ->
  Mov = hipe_icode:mk_move(mk_var(Dst),trans_const(String)),
  [Mov | trans_fun(Instructions,Env)];
%%--- put_list ---
trans_fun([{put_list,Car,Cdr,Dest}|Instructions], Env) ->
  {M1,V1,Env2} = mk_move_and_var(Car,Env),
  {M2,V2,Env3} = mk_move_and_var(Cdr,Env2),
  D = mk_var(Dest),
  M1 ++ M2 ++ [hipe_icode:mk_primop([D],cons,[V1,V2])
	       | trans_fun(Instructions,Env3)];
%%--- put_tuple ---
trans_fun([{put_tuple,_Size,Reg}|Instructions], Env) ->
  {Moves,Instructions2,Vars,Env2} = trans_puts(Instructions,Env),
  Dest = [mk_var(Reg)],
  Src = lists:reverse(Vars),
  Primop = hipe_icode:mk_primop(Dest,mktuple,Src),
  Moves ++ [Primop | trans_fun(Instructions2,Env2)];
%%--- put --- SHOULD NOT REALLY EXIST HERE; put INSTRUCTIONS ARE HANDLED ABOVE.
%%--- badmatch ---
trans_fun([{badmatch,Arg}|Instructions], Env) ->
  BadVar = trans_arg(Arg),
  ErrVar = mk_var(new),
  Vs = [mk_var(new)],
  Atom = hipe_icode:mk_move(ErrVar,hipe_icode:mk_const(badmatch)),
  Tuple = hipe_icode:mk_primop(Vs,mktuple,[ErrVar,BadVar]),
  Fail = hipe_icode:mk_fail(Vs,error),
  [Atom,Tuple,Fail | trans_fun(Instructions,Env)];
%%--- if_end ---
trans_fun([if_end|Instructions], Env) ->
  V = mk_var(new),
  Mov = hipe_icode:mk_move(V,hipe_icode:mk_const(if_clause)),
  Fail = hipe_icode:mk_fail([V],error),
  [Mov,Fail | trans_fun(Instructions, Env)];
%%--- case_end ---
trans_fun([{case_end,Arg}|Instructions], Env) ->
  BadArg = trans_arg(Arg),
  ErrVar = mk_var(new),
  Vs = [mk_var(new)],
  Atom = hipe_icode:mk_move(ErrVar,hipe_icode:mk_const(case_clause)),
  Tuple = hipe_icode:mk_primop(Vs,mktuple,[ErrVar,BadArg]),
  Fail = hipe_icode:mk_fail(Vs,error),
  [Atom,Tuple,Fail | trans_fun(Instructions,Env)];
%%--- enter_fun ---
trans_fun([{call_fun,N},{deallocate,_},return|Instructions], Env) ->
  Args = extract_fun_args(N+1), %% +1 is for the fun itself
  [hipe_icode:mk_comment('enter_fun'),
   hipe_icode:mk_enter_primop(enter_fun,Args) | trans_fun(Instructions,Env)];
%%--- call_fun ---
trans_fun([{call_fun,N}|Instructions], Env) ->
  Args = extract_fun_args(N+1), %% +1 is for the fun itself
  Dst = [mk_var({r,0})],
  [hipe_icode:mk_comment('call_fun'),
   hipe_icode:mk_primop(Dst,call_fun,Args) | trans_fun(Instructions,Env)];
%%--- patched_make_fun --- make_fun/make_fun2 after fixes
trans_fun([{patched_make_fun,MFA,Magic,FreeVarNum,Index}|Instructions], Env) ->
  Args = extract_fun_args(FreeVarNum),
  Dst = [mk_var({r,0})],
  Fun = hipe_icode:mk_primop(Dst,
			     #mkfun{mfa=MFA,magic_num=Magic,index=Index},
			     Args),
  ?no_debug_msg("mkfun translates to: ~p~n",[Fun]),
  [Fun | trans_fun(Instructions,Env)];
%%--- is_function ---
trans_fun([{test,is_function,{f,Lbl},[Arg]}|Instructions], Env) ->
  {Code,Env1} = trans_type_test(function,Lbl,Arg,Env),
  [Code | trans_fun(Instructions,Env1)];
%%--- call_ext_only ---
trans_fun([{call_ext_only,_N,{extfunc,M,F,A}}|Instructions], Env) ->
  Args = extract_fun_args(A),
  I = trans_enter({M,F,A}, Args, remote),
  [hipe_icode:mk_comment('call_ext_only'), I | trans_fun(Instructions,Env)];
%%--------------------------------------------------------------------
%%--- Translation of binary instructions ---
%%--------------------------------------------------------------------
%% This code uses a somewhat unorthodox translation:
%%   Since we do not want non-erlang values as arguments to Icode
%%   instructions some compile time constants are coded into the
%%   name of the function (or rather the primop).
%% TODO: Make sure all cases of argument types are covered.
%%--------------------------------------------------------------------
trans_fun([{test,bs_start_match2,{f,Lbl},[X,_Live,Max,Ms]}|Instructions], Env) ->
  Bin = trans_arg(X),
  MsVar = mk_var(Ms),
  trans_op_call({hipe_bs_primop, {bs_start_match, Max}}, Lbl, [Bin],
		[MsVar], Env, Instructions);
trans_fun([{test,bs_get_float2,{f,Lbl},[Ms,_Live,Size,Unit,{field_flags,Flags0},X]}|
	   Instructions], Env) ->  
  Dst = mk_var(X),
  MsVar = mk_var(Ms),
  Flags = resolve_native_endianess(Flags0),
  {Name, Args} = 
    case Size of
      {integer, NoBits} when is_integer(NoBits), NoBits >= 0 -> 
	{{bs_get_float,NoBits*Unit,Flags}, [MsVar]};
      {integer, NoBits} when is_integer(NoBits), NoBits < 0 ->
	?EXIT({bad_bs_size_constant,Size});
      BitReg ->
	Bits = mk_var(BitReg),
	{{bs_get_float,Unit,Flags}, [Bits,MsVar]}
    end,
  trans_op_call({hipe_bs_primop,Name}, Lbl, Args, [Dst,MsVar], Env, Instructions);
trans_fun([{test,bs_get_integer2,{f,Lbl},[Ms,_Live,Size,Unit,{field_flags,Flags0},X]}|
	   Instructions], Env) ->
  Dst = mk_var(X),
  MsVar = mk_var(Ms),
  Flags = resolve_native_endianess(Flags0),
  {Name, Args} = 
    case Size of
      {integer,NoBits} when is_integer(NoBits), NoBits >= 0 -> 
	{{bs_get_integer,NoBits*Unit,Flags}, [MsVar]};
      {integer,NoBits} when is_integer(NoBits), NoBits < 0 ->
	?EXIT({bad_bs_size_constant,Size});
      BitReg ->
	Bits = mk_var(BitReg),
	{{bs_get_integer,Unit,Flags}, [MsVar,Bits]}
    end,
  trans_op_call({hipe_bs_primop,Name}, Lbl, Args, [Dst,MsVar], Env, Instructions);
trans_fun([{test,bs_get_binary2,{f,Lbl},[Ms,_Live,Size,Unit,{field_flags,Flags},X]}| 
	   Instructions], Env) ->
  MsVar = mk_var(Ms),
  {Name, Args, Dsts} =
    case Size of
      {atom, all} -> %% put all bits
	if Ms =:= X ->
	    {{bs_get_binary_all,Unit,Flags},[MsVar],[mk_var(X)]};
	   true ->
	    {{bs_get_binary_all_2,Unit,Flags},[MsVar],[mk_var(X),MsVar]}
	end;
      {integer, NoBits} when is_integer(NoBits), NoBits >= 0 ->
	{{bs_get_binary,NoBits*Unit,Flags}, [MsVar], [mk_var(X),MsVar]};%% Create a N*Unit bits subbinary
      {integer, NoBits} when is_integer(NoBits), NoBits < 0 ->
	?EXIT({bad_bs_size_constant,Size});
      BitReg -> % Use a number of bits only known at runtime.
	Bits = mk_var(BitReg),
	{{bs_get_binary,Unit,Flags}, [MsVar,Bits], [mk_var(X),MsVar]}
    end,
  trans_op_call({hipe_bs_primop,Name}, Lbl, Args, Dsts, Env, Instructions);
trans_fun([{test,bs_skip_bits2,{f,Lbl},[Ms,Size,NumBits,{field_flags,Flags}]}|
	   Instructions], Env) -> 
  %% the current match buffer
  MsVar = mk_var(Ms),
  {Name, Args} = 
    case Size of
      {atom, all} -> %% Skip all bits
	{{bs_skip_bits_all,NumBits,Flags},[MsVar]};
      {integer, BitSize} when is_integer(BitSize), BitSize >= 0-> %% Skip N bits
	{{bs_skip_bits,BitSize*NumBits}, [MsVar]};
      {integer, BitSize} when is_integer(BitSize), BitSize < 0 ->
	?EXIT({bad_bs_size_constant,Size});
      X -> % Skip a number of bits only known at runtime.
	Src = mk_var(X),
	{{bs_skip_bits,NumBits},[MsVar,Src]}
    end,
  trans_op_call({hipe_bs_primop,Name}, Lbl, Args, [MsVar], Env, Instructions);
trans_fun([{test,bs_test_unit,{f,Lbl},[Ms,Unit]}|
	   Instructions], Env) -> 
  %% the current match buffer
  MsVar = mk_var(Ms),
  trans_op_call({hipe_bs_primop,{bs_test_unit,Unit}}, Lbl, 
		[MsVar], [], Env, Instructions);
trans_fun([{test,bs_match_string,{f,Lbl},[Ms,BitSize,Bin]}|
	   Instructions], Env) -> 
  True = mk_label(new),
  FalseLabName = map_label(Lbl),
  TrueLabName = hipe_icode:label_name(True),
  MsVar = mk_var(Ms),
  TmpVar = mk_var(new),
  ByteSize = BitSize div 8,
  ExtraBits = BitSize rem 8,
  WordSize = hipe_rtl_arch:word_size(),
  if ExtraBits =:= 0 ->
      trans_op_call({hipe_bs_primop,{bs_match_string,Bin,ByteSize}}, Lbl, 
		    [MsVar], [MsVar], Env, Instructions);
      BitSize =< ((WordSize * 8) - 5) -> 
      <<Int:BitSize, _/bits>> = Bin,
      {I1,Env1} = trans_one_op_call({hipe_bs_primop,{bs_get_integer,BitSize,0}}, Lbl, 
				    [MsVar], [TmpVar, MsVar], Env), 
      I2 = hipe_icode:mk_type([TmpVar], {integer,Int}, TrueLabName, FalseLabName),
      I1 ++ [I2,True] ++ trans_fun(Instructions, Env1);
     true ->
      <<RealBin:ByteSize/binary, Int:ExtraBits, _/bits>> = Bin,
      {I1,Env1} = trans_one_op_call({hipe_bs_primop,{bs_match_string,RealBin,ByteSize}}, Lbl, 
				    [MsVar], [MsVar], Env),
      {I2,Env2} = trans_one_op_call({hipe_bs_primop,{bs_get_integer,ExtraBits,0}}, Lbl, 
				    [MsVar], [TmpVar, MsVar], Env1),
      I3 = hipe_icode:mk_type([TmpVar], {integer,Int}, TrueLabName, FalseLabName),
      I1 ++ I2 ++ [I3,True] ++ trans_fun(Instructions, Env2)
  end;
trans_fun([{bs_context_to_binary,Var}|Instructions], Env) -> 
  %% the current match buffer
  IVars = [trans_arg(Var)],
  [hipe_icode:mk_primop(IVars,{hipe_bs_primop,bs_context_to_binary},IVars)|
   trans_fun(Instructions, Env)];
trans_fun([{bs_append,{f,Lbl},Size,W,R,U,Binary,{field_flags,F},Dst}| 
	   Instructions], Env) -> 
  %% the current match buffer
  SizeArg = trans_arg(Size),
  BinArg = trans_arg(Binary),
  IcodeDst = mk_var(Dst),
  Offset = mk_var(reg),
  Base = mk_var(reg),
  trans_bin_call({hipe_bs_primop,{bs_append,W,R,U,F}},Lbl,[SizeArg,BinArg],
		[IcodeDst,Base,Offset],
		 Base, Offset, Env, Instructions);
trans_fun([{bs_private_append,{f,Lbl},Size,U,Binary,{field_flags,F},Dst}| 
	   Instructions], Env) -> 
  %% the current match buffer
  SizeArg = trans_arg(Size),
  BinArg = trans_arg(Binary),
  IcodeDst = mk_var(Dst),
  Offset = mk_var(reg),
  Base = mk_var(reg),
  trans_bin_call({hipe_bs_primop,{bs_private_append,U,F}},
		 Lbl,[SizeArg,BinArg],
		 [IcodeDst,Base,Offset],
		 Base, Offset, Env, Instructions);
trans_fun([bs_init_writable|Instructions], Env) -> 
  Vars = [mk_var({x,0})], %{x,0} is implict arg and dst
  [hipe_icode:mk_primop(Vars,{hipe_bs_primop,bs_init_writable},Vars),
   trans_fun(Instructions, Env)];
trans_fun([{bs_save2,Ms,IndexName}|Instructions], Env) ->
  Index =
    case IndexName of
      {atom, start} -> 0;
      _ -> IndexName+1
    end,
  MsVars = [mk_var(Ms)],
  [hipe_icode:mk_primop(MsVars,{hipe_bs_primop,{bs_save,Index}},MsVars) |
   trans_fun(Instructions, Env)];
trans_fun([{bs_restore2,Ms,IndexName}|Instructions], Env) ->
  Index =
    case IndexName of
      {atom, start} -> 0;
      _ -> IndexName+1
    end,
  MsVars = [mk_var(Ms)],
  [hipe_icode:mk_primop(MsVars,{hipe_bs_primop,{bs_restore,Index}},MsVars) |
   trans_fun(Instructions, Env)];
trans_fun([{test,bs_test_tail2,{f,Lbl},[Ms,Numbits]}| Instructions], Env) ->
  MsVar = mk_var(Ms),
  trans_op_call({hipe_bs_primop,{bs_test_tail,Numbits}}, 
		Lbl, [MsVar], [], Env, Instructions);
%%--------------------------------------------------------------------
%% New bit syntax instructions added in February 2004 (R10B).
%%--------------------------------------------------------------------
trans_fun([{bs_init2,{f,Lbl},Size,_Words,_LiveRegs,{field_flags,Flags0},X}|
	   Instructions], Env) ->
  Dst = mk_var(X),
  Flags = resolve_native_endianess(Flags0),
  Offset = mk_var(reg),
  Base = mk_var(reg),
  {Name, Args} =
    case Size of
      NoBytes when is_integer(NoBytes) ->
	{{bs_init, Size, Flags}, []};
      BitReg ->
	Bits = mk_var(BitReg),
	{{bs_init, Flags}, [Bits]}
    end,
  trans_bin_call({hipe_bs_primop,Name}, Lbl, Args, [Dst, Base, Offset],
		 Base, Offset, Env, Instructions);
trans_fun([{bs_init_bits,{f,Lbl},Size,_Words,_LiveRegs,{field_flags,Flags0},X}|
	   Instructions], Env) ->
  Dst = mk_var(X),
  Flags = resolve_native_endianess(Flags0),
  Offset = mk_var(reg),
  Base = mk_var(reg),
  {Name, Args} =
    case Size of
      NoBits when is_integer(NoBits) ->
	{{bs_init_bits, NoBits, Flags}, []};
      BitReg ->
	Bits = mk_var(BitReg),
	{{bs_init_bits, Flags}, [Bits]}
    end,
  trans_bin_call({hipe_bs_primop,Name}, Lbl, Args, [Dst, Base, Offset],
		 Base, Offset, Env, Instructions);
trans_fun([{bs_add, {f,Lbl}, [Old,New,Unit], Res}|Instructions], Env) ->
  Dst = mk_var(Res),
  Temp = mk_var(new),
  MultIs =
    case {New,Unit} of
      {{integer, NewInt}, _} ->
	[hipe_icode:mk_move(Temp, hipe_icode:mk_const(NewInt*Unit))];
      {_, 1} ->
	NewVar = mk_var(New),
	[hipe_icode:mk_move(Temp, NewVar)];
      _ ->
	NewVar = mk_var(New),
	if Lbl =:= 0 ->
	    [hipe_icode:mk_primop([Temp], '*', 
				  [NewVar, hipe_icode:mk_const(Unit)])];
	   true ->
	    Succ = mk_label(new),
	    [hipe_icode:mk_primop([Temp], '*', 
				  [NewVar, hipe_icode:mk_const(Unit)],
				  hipe_icode:label_name(Succ), Lbl),
	     Succ]
	end
    end,
  Succ2 = mk_label(new),
  {FailLblName, FailCode} = 
    if Lbl =:= 0 ->
	FailLbl = mk_label(new),
	{hipe_icode:label_name(FailLbl),
	 [FailLbl,
	  hipe_icode:mk_fail([hipe_icode:mk_const(badarg)], error)]};
       true ->
	{Lbl, []}
    end,
  IsPos = 
    [hipe_icode:mk_if('>=', [Temp, hipe_icode:mk_const(0)], 
		      hipe_icode:label_name(Succ2), FailLblName)] ++
    FailCode ++ [Succ2], 
  AddI =
    case Old of
      {integer,OldInt} ->
	hipe_icode:mk_primop([Dst], '+', [Temp, hipe_icode:mk_const(OldInt)]);
      _ ->
	OldVar = mk_var(Old),
	hipe_icode:mk_primop([Dst], '+', [Temp, OldVar])
    end,
  MultIs ++ IsPos ++ [AddI|trans_fun(Instructions, Env)];
%%--------------------------------------------------------------------
%% Bit syntax instructions added in R12B-5 (Fall 2008)
%%--------------------------------------------------------------------
trans_fun([{bs_utf8_size,{f,Lbl},A2,A3}|Instructions], Env) ->
  Bin = trans_arg(A2),
  Dst = mk_var(A3),
  trans_op_call({hipe_bs_primop, bs_utf8_size}, Lbl, [Bin], [Dst], Env, Instructions);
trans_fun([{test,bs_get_utf8,{f,Lbl},[Ms,_Live,{field_flags,_Flags},X]} |
	   Instructions], Env) ->
  trans_bs_get_or_skip_utf8(Lbl, Ms, X, Instructions, Env);
trans_fun([{test,bs_skip_utf8,{f,Lbl},[Ms,_Live,{field_flags,_Flags}]} |
	   Instructions], Env) ->
  trans_bs_get_or_skip_utf8(Lbl, Ms, 'new', Instructions, Env);
trans_fun([{bs_utf16_size,{f,Lbl},A2,A3}|Instructions], Env) ->
  Bin = trans_arg(A2),
  Dst = mk_var(A3),
  trans_op_call({hipe_bs_primop, bs_utf16_size}, Lbl, [Bin], [Dst], Env, Instructions);
trans_fun([{test,bs_get_utf16,{f,Lbl},[Ms,_Live,{field_flags,Flags0},X]} |
	   Instructions], Env) ->
  trans_bs_get_or_skip_utf16(Lbl, Ms, Flags0, X, Instructions, Env);
trans_fun([{test,bs_skip_utf16,{f,Lbl},[Ms,_Live,{field_flags,Flags0}]} |
	   Instructions], Env) ->
  trans_bs_get_or_skip_utf16(Lbl, Ms, Flags0, 'new', Instructions, Env);
trans_fun([{test,bs_get_utf32,{f,Lbl},[Ms,_Live,{field_flags,Flags0},X]} | Instructions], Env) ->
  trans_bs_get_or_skip_utf32(Lbl, Ms, Flags0, X, Instructions, Env);
trans_fun([{test,bs_skip_utf32,{f,Lbl},[Ms,_Live,{field_flags,Flags0}]} | Instructions], Env) ->
  trans_bs_get_or_skip_utf32(Lbl, Ms, Flags0, 'new', Instructions, Env);
%%--------------------------------------------------------------------
%%--- Translation of floating point instructions ---
%%--------------------------------------------------------------------
%%--- fclearerror ---
trans_fun([fclearerror|Instructions], Env) ->
  case get(hipe_inline_fp) of
    true ->  
      [hipe_icode:mk_primop([], fclearerror, []) | 
       trans_fun(Instructions,Env)];
    _ ->
      trans_fun(Instructions,Env)
  end;
%%--- fcheckerror ---
trans_fun([{fcheckerror,{_,Fail}}|Instructions], Env) ->
  case get(hipe_inline_fp) of
    true ->
      ContLbl = mk_label(new),
      case Fail of
	0 -> 
	  [hipe_icode:mk_primop([], fcheckerror, [],
				hipe_icode:label_name(ContLbl), []),
	   ContLbl | trans_fun(Instructions,Env)];
	_ -> %% Can this happen?
	  {Guard,Env1} =
	    make_guard([], fcheckerror, [],
		       hipe_icode:label_name(ContLbl), map_label(Fail), Env),
	  [Guard, ContLbl | trans_fun(Instructions,Env1)]
      end;
    _ ->
      trans_fun(Instructions, Env)
  end;
%%--- fmove ---
trans_fun([{fmove,Src,Dst}|Instructions], Env) ->
  case get(hipe_inline_fp) of
    true ->
      Dst1 = mk_var(Dst),
      Src1 = trans_arg(Src),
      case{hipe_icode:is_fvar(Dst1),
	   hipe_icode:is_fvar(Src1)} of
	{true, true} -> %% fvar := fvar 
	  [hipe_icode:mk_move(Dst1,Src1) | trans_fun(Instructions,Env)];
	{false, true} -> %% var := fvar
	  [hipe_icode:mk_primop([Dst1], unsafe_tag_float, [Src1]) |
	   trans_fun(Instructions,Env)];
	{true, false} -> %% fvar := var or fvar := constant
	  [hipe_icode:mk_primop([Dst1], unsafe_untag_float, [Src1]) |
	   trans_fun(Instructions,Env)]      
      end;
    _ ->
      trans_fun([{move,Src,Dst}|Instructions], Env)
  end;
%%--- fconv ---
trans_fun([{fconv,Eterm,FReg}|Instructions], Env) ->
  case get(hipe_inline_fp) of
    true ->
      Src = trans_arg(Eterm),
      ContLbl = mk_label(new),
      Dst = mk_var(FReg),
      [hipe_icode:mk_primop([Dst], conv_to_float, [Src], 
			    hipe_icode:label_name(ContLbl), []),
       ContLbl| trans_fun(Instructions, Env)];
    _ ->
      trans_fun([{fmove,Eterm,FReg}|Instructions], Env)
  end;
%%--- fadd ---
trans_fun([{arithfbif,fadd,Lab,SrcRs,DstR}|Instructions], Env) ->
  case get(hipe_inline_fp) of
    true ->
      trans_fun([{arithbif,fp_add,Lab,SrcRs,DstR}|Instructions], Env);
    _ ->
      trans_fun([{arithbif,'+',Lab,SrcRs,DstR}|Instructions], Env)
  end;
%%--- fsub ---
trans_fun([{arithfbif,fsub,Lab,SrcRs,DstR}|Instructions], Env) ->
  case get(hipe_inline_fp) of
    true ->
      trans_fun([{arithbif,fp_sub,Lab,SrcRs,DstR}|Instructions], Env);
    _ ->
      trans_fun([{arithbif,'-',Lab,SrcRs,DstR}|Instructions], Env)
  end;
%%--- fmult ---
trans_fun([{arithfbif,fmul,Lab,SrcRs,DstR}|Instructions], Env) ->
  case get(hipe_inline_fp) of
    true ->
      trans_fun([{arithbif,fp_mul,Lab,SrcRs,DstR}|Instructions], Env);
    _ ->
      trans_fun([{arithbif,'*',Lab,SrcRs,DstR}|Instructions], Env)
  end;
%%--- fdiv ---
trans_fun([{arithfbif,fdiv,Lab,SrcRs,DstR}|Instructions], Env) ->
  case get(hipe_inline_fp) of
    true ->
      trans_fun([{arithbif,fp_div,Lab,SrcRs,DstR}|Instructions], Env);
    _ ->
      trans_fun([{arithbif,'/',Lab,SrcRs,DstR}|Instructions], Env)
  end;
%%--- fnegate ---
trans_fun([{arithfbif,fnegate,Lab,[SrcR],DestR}|Instructions], Env) ->
  case get(hipe_inline_fp) of
    true ->
      Src = trans_arg(SrcR),
      Dst = mk_var(DestR),
      [hipe_icode:mk_primop([Dst], fnegate, [Src])| 
       trans_fun(Instructions,Env)];
    _ ->
      trans_fun([{arithbif,'-',Lab,[{float,0.0},SrcR],DestR}|Instructions], Env)
  end;
%%--------------------------------------------------------------------
%% New apply instructions added in April 2004 (R10B).
%%--------------------------------------------------------------------
trans_fun([{apply,Arity}|Instructions], Env) ->
  BeamArgs = extract_fun_args(Arity+2), %% +2 is for M and F
  {Args,[M,F]} = lists:split(Arity,BeamArgs),
  Dst = [mk_var({r,0})],
  [hipe_icode:mk_comment('apply'),
   hipe_icode:mk_primop(Dst, #apply_N{arity=Arity}, [M,F|Args])
   | trans_fun(Instructions,Env)];
trans_fun([{apply_last,Arity,_N}|Instructions], Env) -> % N is StackAdjustment?
  BeamArgs = extract_fun_args(Arity+2), %% +2 is for M and F
  {Args,[M,F]} = lists:split(Arity,BeamArgs),
  [hipe_icode:mk_comment('apply_last'),
   hipe_icode:mk_enter_primop(#apply_N{arity=Arity}, [M,F|Args])
   | trans_fun(Instructions,Env)];
%%--------------------------------------------------------------------
%% New test instruction added in April 2004 (R10B).
%%--------------------------------------------------------------------
%%--- is_boolean ---
trans_fun([{test,is_boolean,{f,Lbl},[Arg]}|Instructions], Env) ->
  {Code,Env1} = trans_type_test(boolean,Lbl,Arg,Env),
  [Code | trans_fun(Instructions,Env1)];
%%--------------------------------------------------------------------
%% New test instruction added in June 2005 for R11
%%--------------------------------------------------------------------
%%--- is_function2 ---
trans_fun([{test,is_function2,{f,Lbl},[Arg,Arity]}|Instructions], Env) ->
  {Code,Env1} = trans_type_test2(function2,Lbl,Arg,Arity,Env),
  [Code | trans_fun(Instructions,Env1)];
%%--------------------------------------------------------------------
%% New garbage-collecting BIFs added in January 2006 for R11B.
%%--------------------------------------------------------------------
trans_fun([{gc_bif,'-',Fail,_Live,[SrcR],DstR}|Instructions], Env) ->
  %% Unary minus. Change this to binary minus.
  trans_fun([{arithbif,'-',Fail,[{integer,0},SrcR],DstR}|Instructions], Env);
trans_fun([{gc_bif,'+',Fail,_Live,[SrcR],DstR}|Instructions], Env) ->
  %% Unary plus. Change this to a bif call.
  trans_fun([{bif,'+',Fail,[SrcR],DstR}|Instructions], Env);
trans_fun([{gc_bif,Name,Fail,_Live,SrcRs,DstR}|Instructions], Env) ->
  case erl_internal:guard_bif(Name, length(SrcRs)) of
    false ->
      %% Arithmetic instruction.
      trans_fun([{arithbif,Name,Fail,SrcRs,DstR}|Instructions], Env);
    true ->
      %% A guard BIF.
      trans_fun([{bif,Name,Fail,SrcRs,DstR}|Instructions], Env)
  end;
%%--------------------------------------------------------------------
%% New test instruction added in July 2007 for R12.
%%--------------------------------------------------------------------
%%--- is_bitstr ---
trans_fun([{test,is_bitstr,{f,Lbl},[Arg]}|Instructions], Env) ->
  {Code,Env1} = trans_type_test(bitstr, Lbl, Arg, Env),
  [Code | trans_fun(Instructions, Env1)];
%%--------------------------------------------------------------------
%% New stack triming instruction added in October 2007 for R12.
%%--------------------------------------------------------------------
trans_fun([{trim,N,NY}|Instructions], Env) ->
  %% trim away N registers leaving NY registers
  Moves = trans_trim(N, NY),
  Moves ++ trans_fun(Instructions, Env);
%%--------------------------------------------------------------------
%%--- ERROR HANDLING ---
%%--------------------------------------------------------------------
trans_fun([X|_], _) ->
  ?EXIT({'trans_fun/2',X});
trans_fun([], _) ->
  [].

%%--------------------------------------------------------------------
%% trans_call and trans_enter generate correct Icode calls/tail-calls,
%% recognizing explicit fails.
%%--------------------------------------------------------------------

trans_call(MFA={M,F,_A}, Dst, Args, Type) ->
  handle_fail(MFA, Args, fun () -> hipe_icode:mk_call(Dst,M,F,Args,Type) end).

trans_enter(MFA={M,F,_A}, Args, Type) ->
  handle_fail(MFA, Args, fun () -> hipe_icode:mk_enter(M,F,Args,Type) end).

handle_fail(MFA, Args, F) ->
  case MFA of
    {erlang,exit,1} ->
      hipe_icode:mk_fail(Args,exit);
    {erlang,throw,1} ->
      hipe_icode:mk_fail(Args,throw);
    {erlang,fault,1} ->
      hipe_icode:mk_fail(Args,error);
    {erlang,fault,2} ->
      hipe_icode:mk_fail(Args,error);
    {erlang,error,1} ->
      hipe_icode:mk_fail(Args,error);
    {erlang,error,2} ->
      hipe_icode:mk_fail(Args,error);
    _ ->
      F()
  end.

%%-----------------------------------------------------------------------
%% trans_bif0(BifName, DestReg)
%% trans_bif(Arity, BifName, FailLab, Args, DestReg, Environment)
%%-----------------------------------------------------------------------

trans_bif0(BifName, DestReg) ->
  ?no_debug_msg("  found BIF0: ~p() ...~n", [BifName]),
  BifRes = mk_var(DestReg),
  hipe_icode:mk_call([BifRes],erlang,BifName,[],remote).

trans_bif(Arity, BifName, Lbl, Args, DestReg, Env) ->
  ?no_debug_msg("  found BIF: ~p(~p) ...~n", [BifName,Args]),
  BifRes = mk_var(DestReg),
  {Movs, SrcVars, Env1} = get_constants_in_temps(Args,Env),
  case Lbl of
    0 -> % Bif is not in a guard
      I = hipe_icode:mk_call([BifRes],erlang,BifName,SrcVars,remote),
      {Movs ++ [I], Env1};
    _ -> % Bif occurs in a guard - fail silently to Lbl
      {GuardI,Env2} =
	make_fallthrough_guard([BifRes],{erlang,BifName,Arity},SrcVars,
			       map_label(Lbl),Env1),
      {[Movs,GuardI], Env2}
  end.

trans_op_call(Name, Lbl, Args, Dests, Env, Instructions) ->
  {Code, Env1} = trans_one_op_call(Name, Lbl, Args, Dests, Env),
  [Code|trans_fun(Instructions, Env1)].

trans_one_op_call(Name, Lbl, Args, Dests, Env) ->
  case Lbl of
      0 -> % Op is not in a guard
	I = hipe_icode:mk_primop(Dests, Name, Args),
	{[I], Env};
      _ -> % op occurs in a guard - fail silently to Lbl
	make_fallthrough_guard(Dests, Name, Args, map_label(Lbl), Env)
    end.

%%-----------------------------------------------------------------------
%% trans_bin_call
%%-----------------------------------------------------------------------

trans_bin_call(Name, Lbl, Args, Dests, Base, Offset, Env, Instructions) ->
  {Code, Env1} =
    case Lbl of
      0 -> % Op is not in a guard
	I = hipe_icode:mk_primop(Dests, Name, Args),
	{[I], Env};
      _ -> % op occurs in a guard - fail silently to Lbl
	make_fallthrough_guard(Dests, Name, Args, map_label(Lbl), Env)
    end,
  [Code|trans_bin(Instructions, Base, Offset, Env1)].

%% Translate instructions for building binaries separately to give
%% them an appropriate state

trans_bin([{bs_put_float,{f,Lbl},Size,Unit,{field_flags,Flags0},Source}|
	   Instructions], Base, Offset, Env) ->
  Flags = resolve_native_endianess(Flags0),
  %% Get source
  {Src,SourceInstrs,ConstInfo} = 
    case is_var(Source) of
      true ->
	{mk_var(Source),[], var};
      false ->
	case Source of
	  {float, X} when is_float(X) ->
	    C = trans_const(Source),
	    SrcVar = mk_var(new),
	    I = hipe_icode:mk_move(SrcVar, C),
	    {SrcVar,[I],pass};
	  _ -> 
	    C = trans_const(Source),
	    SrcVar = mk_var(new),
	    I = hipe_icode:mk_move(SrcVar, C),
	    {SrcVar,[I],fail}
	end
    end,
  %% Get type of put_float
  {Name,Args,Env2} = 
    case Size of
      {integer,NoBits} when is_integer(NoBits), NoBits >= 0 ->
	%% Create a N*Unit bits float
	{{bs_put_float, NoBits*Unit, Flags, ConstInfo}, [Src, Base, Offset], Env};
      {integer,NoBits} when is_integer(NoBits), NoBits < 0 ->
	?EXIT({bad_bs_size_constant,Size});
      BitReg -> % Use a number of bits only known at runtime.
	Bits = mk_var(BitReg),
	{{bs_put_float, Unit, Flags, ConstInfo}, [Src,Bits,Base,Offset], Env}
    end,
  %% Generate code for calling the bs-op. 
  SourceInstrs ++ 
    trans_bin_call({hipe_bs_primop,Name}, Lbl, Args, [Offset], Base, Offset, Env2, Instructions);
trans_bin([{bs_put_binary,{f,Lbl},Size,Unit,{field_flags,Flags},Source}|
	   Instructions], Base, Offset, Env) ->
  %% Get the source of the binary.
  Src = trans_arg(Source), 
  %% Get type of put_binary
  {Name, Args, Env2} =
    case Size of
      {atom,all} -> %% put all bits
	{{bs_put_binary_all, Flags}, [Src,Base,Offset], Env};
      {integer,NoBits} when is_integer(NoBits), NoBits >= 0 ->
	%% Create a N*Unit bits subbinary
	{{bs_put_binary, NoBits*Unit, Flags}, [Src,Base,Offset], Env};
      {integer,NoBits} when is_integer(NoBits), NoBits < 0 ->
	?EXIT({bad_bs_size_constant,Size});
      BitReg -> % Use a number of bits only known at runtime.
	Bits = mk_var(BitReg),
	{{bs_put_binary, Unit, Flags}, [Src, Bits,Base,Offset], Env}
    end,
  %% Generate code for calling the bs-op.
  trans_bin_call({hipe_bs_primop, Name}, 
		 Lbl, Args, [Offset],
		 Base, Offset, Env2, Instructions);
%%--- bs_put_string ---
trans_bin([{bs_put_string,SizeInBytes,{string,String}}|Instructions], Base, 
	  Offset, Env) ->
  [hipe_icode:mk_primop([Offset],
			{hipe_bs_primop,{bs_put_string, String, SizeInBytes}},
			[Base, Offset]) |
   trans_bin(Instructions, Base, Offset, Env)];
trans_bin([{bs_put_integer,{f,Lbl},Size,Unit,{field_flags,Flags0},Source}|
	   Instructions], Base, Offset, Env) ->
  Flags = resolve_native_endianess(Flags0),
  %% Get size-type 
  
  %% Get the source of the binary.
  {Src, SrcInstrs, ConstInfo} = 
    case is_var(Source) of
      true ->
	{mk_var(Source), [], var};
      false ->
	case Source of
	  {integer, X} when is_integer(X) ->
	    C = trans_const(Source),
	    SrcVar = mk_var(new),
	    I = hipe_icode:mk_move(SrcVar, C),
	    {SrcVar,[I], pass};
	  _ ->
	    C = trans_const(Source),
	    SrcVar = mk_var(new),
	    I = hipe_icode:mk_move(SrcVar, C),
	    {SrcVar,[I], fail}
	    
	end
    end,
  {Name, Args, Env2} = 
    case is_var(Size) of
      true ->
	SVar = mk_var(Size),
	{{bs_put_integer,Unit,Flags,ConstInfo}, [SVar, Base, Offset], Env};
      false ->
	case Size of
	  {integer, NoBits} when NoBits >= 0 -> 
	    {{bs_put_integer,NoBits*Unit,Flags,ConstInfo}, [Base, Offset], Env};
	  _ -> 
	    ?EXIT({bad_bs_size_constant,Size})
	end
    end,
  SrcInstrs ++ trans_bin_call({hipe_bs_primop, Name}, 
			     Lbl, [Src|Args], [Offset], Base, Offset, Env2, Instructions);
%%----------------------------------------------------------------
%% New binary construction instructions added in R12B-5 (Fall 2008).
%%----------------------------------------------------------------
trans_bin([{bs_put_utf8,{f,Lbl},_FF,A3}|Instructions], Base, Offset, Env) ->
  Src = trans_arg(A3),
  Args = [Src, Base, Offset],
  trans_bin_call({hipe_bs_primop, bs_put_utf8}, Lbl, Args, [Offset], Base, Offset, Env, Instructions);
trans_bin([{bs_put_utf16,{f,Lbl},{field_flags,Flags0},A3}|Instructions], Base, Offset, Env) ->
  Src = trans_arg(A3),
  Args = [Src, Base, Offset],
  Flags = resolve_native_endianess(Flags0),
  Name = {bs_put_utf16, Flags},
  trans_bin_call({hipe_bs_primop, Name}, Lbl, Args, [Offset], Base, Offset, Env, Instructions);
trans_bin([{bs_put_utf32,F={f,Lbl},FF={field_flags,_Flags0},A3}|Instructions], Base, Offset, Env) ->
  Src = trans_arg(A3),
  trans_bin_call({hipe_bs_primop,bs_validate_unicode}, Lbl, [Src], [], Base, Offset, Env,
		 [{bs_put_integer,F,{integer,32},1,FF,A3} | Instructions]);
%%----------------------------------------------------------------
%% Base cases for the end of a binary construction sequence.
%%----------------------------------------------------------------
trans_bin([{bs_final2,Src,Dst}|Instructions], _Base, Offset, Env) ->
  [hipe_icode:mk_primop([mk_var(Dst)], {hipe_bs_primop, bs_final}, 
			[trans_arg(Src),Offset])
   |trans_fun(Instructions, Env)];
trans_bin(Instructions, _Base, _Offset, Env) ->
  trans_fun(Instructions, Env).

%% this translates bs_get_utf8 and bs_skip_utf8 (get with new unused dst)
trans_bs_get_or_skip_utf8(Lbl, Ms, X, Instructions, Env) ->
  Dst = mk_var(X),
  MsVar = mk_var(Ms),
  trans_op_call({hipe_bs_primop,bs_get_utf8}, Lbl, [MsVar], [Dst,MsVar], Env, Instructions).

%% this translates bs_get_utf16 and bs_skip_utf16 (get with new unused dst)
trans_bs_get_or_skip_utf16(Lbl, Ms, Flags0, X, Instructions, Env) ->
  Dst = mk_var(X),
  MsVar = mk_var(Ms),
  Flags = resolve_native_endianess(Flags0),
  Name = {bs_get_utf16,Flags},
  trans_op_call({hipe_bs_primop,Name}, Lbl, [MsVar], [Dst,MsVar], Env, Instructions).

%% this translates bs_get_utf32 and bs_skip_utf32 (get with new unused dst)
trans_bs_get_or_skip_utf32(Lbl, Ms, Flags0, X, Instructions, Env) ->
  Dst = mk_var(X),
  MsVar = mk_var(Ms),
  Flags = resolve_native_endianess(Flags0),
  {I1,Env1} = trans_one_op_call({hipe_bs_primop,{bs_get_integer,32,Flags}},
				Lbl, [MsVar], [Dst,MsVar], Env),
  I1 ++ trans_op_call({hipe_bs_primop,bs_validate_unicode_retract},
		      Lbl, [Dst,MsVar], [MsVar], Env1, Instructions).

%%-----------------------------------------------------------------------
%% trans_arith(Op, SrcVars, Des, Lab, Env) -> { Icode, NewEnv }
%%     A failure label of type {f,0} means in a body.
%%     A failure label of type {f,L} where L>0 means in a guard.
%%        Within a guard a failure should branch to the next guard and
%%        not trigger an exception!!
%%     Handles body arithmetic with Icode primops!
%%     Handles guard arithmetic with Icode guardops!
%%-----------------------------------------------------------------------

trans_arith(Op, SrcRs, DstR, Lbl, Env) ->
  {Movs,SrcVars,Env1} = get_constants_in_temps(SrcRs,Env),
  DstVar = mk_var(DstR),
  %%io:format("~w:trans_arith()\n ~w := ~w ~w\n",
  %%		[?MODULE,DstVar,SrcVars,Op]),
  case Lbl of
    0 ->  % Body arithmetic
      Primop = hipe_icode:mk_primop([DstVar], arith_op_name(Op), SrcVars),
      {Movs++[Primop], Env1};
    _ ->  % Guard arithmetic
      {Guard,Env2} = 
	make_fallthrough_guard([DstVar], arith_op_name(Op), SrcVars,
			       map_label(Lbl), Env1),
      {[Movs,Guard], Env2}
  end.

%% Prevent arbitrary names from leaking into Icode from BEAM.
arith_op_name('+') -> '+';
arith_op_name('-') -> '-';
arith_op_name('*') -> '*';
arith_op_name('/') -> '/';
arith_op_name('div') -> 'div';
arith_op_name('fp_add') -> 'fp_add';
arith_op_name('fp_sub') -> 'fp_sub';
arith_op_name('fp_mul') -> 'fp_mul';
arith_op_name('fp_div') -> 'fp_div';
arith_op_name('rem') -> 'rem';
arith_op_name('bsl') -> 'bsl';
arith_op_name('bsr') -> 'bsr';
arith_op_name('band') -> 'band';
arith_op_name('bor') -> 'bor';
arith_op_name('bxor') -> 'bxor';
arith_op_name('bnot') -> 'bnot'.

%%-----------------------------------------------------------------------
%%-----------------------------------------------------------------------

trans_test_guard(TestOp,F,Arg1,Arg2,Env) ->
  {Movs,Vars,Env1} = get_constants_in_temps([Arg1,Arg2],Env),
  True = mk_label(new),
  I = hipe_icode:mk_if(TestOp,Vars,hipe_icode:label_name(True),map_label(F)),
  {[Movs,I,True], Env1}.

%%-----------------------------------------------------------------------
%%-----------------------------------------------------------------------

make_fallthrough_guard(DstVar,GuardOp,Args,FailLName,Env) ->
  ContL = mk_label(new),
  ContLName = hipe_icode:label_name(ContL),
  {Instrs, NewDsts} = clone_dsts(DstVar),
  {Guard,Env1} = make_guard(NewDsts,GuardOp,Args,ContLName,FailLName,Env),
  {[Guard,ContL]++Instrs,Env1}.

%% Make sure DstVar gets initialised to a dummy value after a fail:
%make_guard(Dests,{hipe_bs_primop,Primop},Args,ContLName,FailLName,Env) ->
%  {[hipe_icode:mk_guardop(Dests,{hipe_bs_primop,Primop},Args,ContLName,FailLName)],
%   Env};
make_guard(Dests=[_|_],GuardOp,Args,ContLName,FailLName,Env) ->
  TmpFailL = mk_label(new),
  TmpFailLName = hipe_icode:label_name(TmpFailL),
  GuardOpIns = hipe_icode:mk_guardop(Dests,GuardOp,Args,
				     ContLName,TmpFailLName),
  FailCode = [TmpFailL,
	      nillify_all(Dests),
	      hipe_icode:mk_goto(FailLName)],
  {[GuardOpIns|FailCode], Env};
%% A guard that does not return anything:
make_guard([],GuardOp,Args,ContLName,FailLName,Env) ->
  {[hipe_icode:mk_guardop([],GuardOp,Args,ContLName,FailLName)],
   Env}.

nillify_all([Var|Vars]) ->
  [hipe_icode:mk_move(Var,hipe_icode:mk_const([]))|nillify_all(Vars)];
nillify_all([]) -> [].

clone_dsts(Dests) ->
  clone_dsts(Dests, [],[]).

clone_dsts([Dest|Dests], Instrs, NewDests) -> 
  {I,ND} = clone_dst(Dest),
  clone_dsts(Dests, [I|Instrs], [ND|NewDests]);
clone_dsts([], Instrs, NewDests) ->
  {lists:reverse(Instrs), lists:reverse(NewDests)}.

clone_dst(Dest) -> 
  New = 
    case hipe_icode:is_reg(Dest) of
      true ->
	mk_var(reg);
      false ->
	true = hipe_icode:is_var(Dest),	      
	mk_var(new)
    end,
  {hipe_icode:mk_move(Dest, New), New}.


%%-----------------------------------------------------------------------
%% trans_type_test(Test, Lbl, Arg, Env) -> { Icode, NewEnv }
%%     Handles all unary type tests like is_integer etc. 
%%-----------------------------------------------------------------------

trans_type_test(Test, Lbl, Arg, Env) ->
  True = mk_label(new),
  {Move,Var,Env1} = mk_move_and_var(Arg,Env),
  I = hipe_icode:mk_type([Var], Test,
			 hipe_icode:label_name(True), map_label(Lbl)),
  {[Move,I,True],Env1}.

%%
%% This handles binary type tests. Currently, the only such is the new
%% is_function/2 BIF.
%%
trans_type_test2(function2, Lbl, Arg, Arity, Env) ->
  True = mk_label(new),
  {Move1,Var1,Env1} = mk_move_and_var(Arg, Env),
  {Move2,Var2,Env2} = mk_move_and_var(Arity, Env1),
  I = hipe_icode:mk_type([Var1,Var2], function2,
			 hipe_icode:label_name(True), map_label(Lbl)),
  {[Move1,Move2,I,True],Env2}.

%%-----------------------------------------------------------------------
%% trans_puts(Code, Environment) -> 
%%            { Movs, Code, Vars, NewEnv }
%%-----------------------------------------------------------------------

trans_puts(Code, Env) ->
  trans_puts(Code, [], [], Env).

trans_puts([{put,X}|Code], Vars, Moves, Env) ->
  case type(X) of
    var ->
      Var = mk_var(X),
      trans_puts(Code, [Var|Vars], Moves, Env);
    #beam_const{value=C} ->
      Var = mk_var(new),
      Move = hipe_icode:mk_move(Var, hipe_icode:mk_const(C)),
      trans_puts(Code, [Var|Vars], [Move|Moves], Env)
  end;
trans_puts(Code, Vars, Moves, Env) ->    %% No more put operations
  {Moves, Code, Vars, Env}.

%%-----------------------------------------------------------------------
%% The code for this instruction is a bit large because we are treating
%% different cases differently.  We want to use the icode `type' 
%% instruction when it is applicable to take care of match expressions.
%%-----------------------------------------------------------------------

trans_is_eq_exact(Lbl, Arg1, Arg2, Env) ->
  case {is_var(Arg1),is_var(Arg2)} of
    {true,true} ->
      True = mk_label(new),
      I = hipe_icode:mk_if('=:=',
			   [mk_var(Arg1),mk_var(Arg2)],
			   hipe_icode:label_name(True), map_label(Lbl)),
      {[I,True], Env};
    {true,false} -> %% right argument is a constant -- use type()!
      trans_is_eq_exact_var_const(Lbl, Arg1, Arg2, Env);
    {false,true} -> %% mirror of the case above; swap args
      trans_is_eq_exact_var_const(Lbl, Arg2, Arg1, Env);
    {false,false} -> %% both arguments are constants !!!
      case Arg1 =:= Arg2 of
	true ->
	  {[], Env};
	false ->   
	  Never = mk_label(new),
	  I = hipe_icode:mk_goto(map_label(Lbl)),
	  {[I,Never], Env}
      end
  end.

trans_is_eq_exact_var_const(Lbl, Arg1, Arg2, Env) -> % var =:= const
  True = mk_label(new),
  NewArg1 = mk_var(Arg1),
  TrueLabName = hipe_icode:label_name(True),
  FalseLabName = map_label(Lbl),
  I = case Arg2 of
	{float,Float} ->
	  hipe_icode:mk_if('=:=',
			   [NewArg1, hipe_icode:mk_const(Float)],
			   TrueLabName, FalseLabName);
	{literal,Literal} ->
	  hipe_icode:mk_if('=:=',
			   [NewArg1, hipe_icode:mk_const(Literal)],
			   TrueLabName, FalseLabName);
	_ ->
	  hipe_icode:mk_type([NewArg1], Arg2, TrueLabName, FalseLabName)
      end,
  {[I,True], Env}.

%%-----------------------------------------------------------------------
%% ... and this is analogous to the above
%%-----------------------------------------------------------------------

trans_is_ne_exact(Lbl, Arg1, Arg2, Env) ->
  case {is_var(Arg1),is_var(Arg2)} of
    {true,true} ->
      True = mk_label(new),
      I = hipe_icode:mk_if('=/=',
			   [mk_var(Arg1),mk_var(Arg2)],
			   hipe_icode:label_name(True), map_label(Lbl)),
      {[I,True], Env};
    {true,false} -> %% right argument is a constant -- use type()!
      trans_is_ne_exact_var_const(Lbl, Arg1, Arg2, Env);
    {false,true} -> %% mirror of the case above; swap args
      trans_is_ne_exact_var_const(Lbl, Arg2, Arg1, Env);
    {false,false} -> %% both arguments are constants !!!
      case Arg1 =/= Arg2 of
	true ->
	  {[], Env};
	false ->   
	  Never = mk_label(new),
	  I = hipe_icode:mk_goto(map_label(Lbl)),
	  {[I,Never], Env}
      end
  end.

trans_is_ne_exact_var_const(Lbl, Arg1, Arg2, Env) -> % var =/= const
  True = mk_label(new),
  NewArg1 = mk_var(Arg1),
  TrueLabName = hipe_icode:label_name(True),
  FalseLabName = map_label(Lbl),
  I = case Arg2 of
	{float,Float} ->
	  hipe_icode:mk_if('=/=',
			   [NewArg1, hipe_icode:mk_const(Float)],
			   TrueLabName, FalseLabName);
	{literal,Literal} ->
	  hipe_icode:mk_if('=/=',
			   [NewArg1, hipe_icode:mk_const(Literal)],
			   TrueLabName, FalseLabName);
	_ ->
	  hipe_icode:mk_type([NewArg1], Arg2, FalseLabName, TrueLabName)
      end,
  {[I,True], Env}.

%%-----------------------------------------------------------------------
%% Try to do a relatively straightforward optimization: if equality with
%% an atom is used, then convert this test to use of exact equality test
%% with the same atom (which in turn will be translated to a `type' test
%% instruction by the code of trans_is_eq_exact_var_const/4 above).
%%-----------------------------------------------------------------------

trans_is_eq(Lbl, Arg1, Arg2, Env) ->
  case {is_var(Arg1),is_var(Arg2)} of
    {true,true} ->   %% not much can be done in this case
      trans_test_guard('==', Lbl, Arg1, Arg2, Env);
    {true,false} ->  %% optimize this case, if possible
      case Arg2 of
	{atom,_SomeAtom} ->
	  trans_is_eq_exact_var_const(Lbl, Arg1, Arg2, Env);
	_ ->
	  trans_test_guard('==', Lbl, Arg1, Arg2, Env)
      end;
    {false,true} ->  %% probably happens rarely; hence the recursive call
      trans_is_eq(Lbl, Arg2, Arg1, Env);
    {false,false} -> %% both arguments are constants !!!
      case Arg1 == Arg2 of
	true ->
	  {[], Env};
	false ->   
	  Never = mk_label(new),
	  I = hipe_icode:mk_goto(map_label(Lbl)),
	  {[I,Never], Env}
      end
  end.

%%-----------------------------------------------------------------------
%% ... and this is analogous to the above
%%-----------------------------------------------------------------------

trans_is_ne(Lbl, Arg1, Arg2, Env) ->
  case {is_var(Arg1),is_var(Arg2)} of
    {true,true} ->   %% not much can be done in this case
      trans_test_guard('/=', Lbl, Arg1, Arg2, Env);
    {true,false} ->  %% optimize this case, if possible
      case Arg2 of
	{atom,_SomeAtom} ->
	  trans_is_ne_exact_var_const(Lbl, Arg1, Arg2, Env);
	_ ->
	  trans_test_guard('/=', Lbl, Arg1, Arg2, Env)
      end;
    {false,true} ->  %% probably happens rarely; hence the recursive call
      trans_is_ne(Lbl, Arg2, Arg1, Env);
    {false,false} -> %% both arguments are constants !!!
      case Arg1 /= Arg2 of
	true ->
	  {[], Env};
	false ->   
	  Never = mk_label(new),
	  I = hipe_icode:mk_goto(map_label(Lbl)),
	  {[I,Never], Env}
      end
  end.


%%-----------------------------------------------------------------------
%% Translates an allocate instruction into a sequence of initializations
%%-----------------------------------------------------------------------

trans_allocate(N) ->
  trans_allocate(N, []).

trans_allocate(0, Acc) ->
  Acc;
trans_allocate(N, Acc) ->
  Move = hipe_icode:mk_move(mk_var({y,N-1}), 
			    hipe_icode:mk_const('dummy_value')),
  trans_allocate(N-1, [Move|Acc]).

%%-----------------------------------------------------------------------
%% Translates a trim instruction into a sequence of moves
%%-----------------------------------------------------------------------

trans_trim(N, NY) ->
  lists:reverse(trans_trim(N, NY, 0, [])).

trans_trim(_, 0, _, Acc) ->
  Acc;
trans_trim(N, NY, Y, Acc) ->
  Move = hipe_icode:mk_move(mk_var({y,Y}), mk_var({y,N})),
  trans_trim(N+1, NY-1, Y+1, [Move|Acc]).

%%-----------------------------------------------------------------------
%%-----------------------------------------------------------------------

mk_move_and_var(Var, Env) ->
  case type(Var) of
    var ->
      V = mk_var(Var),
      {[], V, Env};
    #beam_const{value=C} ->
      V = mk_var(new),
      {[hipe_icode:mk_move(V,hipe_icode:mk_const(C))], V, Env}
  end.

%%-----------------------------------------------------------------------
%% Find names of closures and number of free vars.
%%-----------------------------------------------------------------------

closure_info_mfa(#closure_info{mfa=MFA}) -> MFA.
closure_info_arity(#closure_info{arity=Arity}) -> Arity.
%% closure_info_fv_arity(#closure_info{fv_arity=Arity}) -> Arity.

find_closure_info(Code) -> mod_find_closure_info(Code, []).

mod_find_closure_info([FunCode|Fs], CI) ->
  mod_find_closure_info(Fs, find_closure_info(FunCode, CI));
mod_find_closure_info([], CI) ->
  CI.

find_closure_info([{patched_make_fun,MFA={_M,_F,A},_Magic,FreeVarNum,_Index}|BeamCode],
		  ClosureInfo) ->
  NewClosure = %% A-FreeVarNum+1 (The real arity + 1 for the closure)
    #closure_info{mfa=MFA, arity=A-FreeVarNum+1, fv_arity=FreeVarNum},
  find_closure_info(BeamCode, [NewClosure|ClosureInfo]);
find_closure_info([_Inst|BeamCode], ClosureInfo) ->
  find_closure_info(BeamCode, ClosureInfo);
find_closure_info([], ClosureInfo) ->
  ClosureInfo.

%%-----------------------------------------------------------------------
%% Is closure
%%-----------------------------------------------------------------------

get_closure_info(MFA, [CI|Rest]) ->
  case closure_info_mfa(CI) of
    MFA -> CI;
    _ -> get_closure_info(MFA, Rest)
  end;
get_closure_info(_, []) ->
  not_a_closure.

%%-----------------------------------------------------------------------
%% Patch closure entry.
%%-----------------------------------------------------------------------

%% NOTE: this changes the number of parameters in the ICode function,
%% but does *not* change the arity in the function name. Thus, all
%% closure-functions have the exact same names in Beam and in native
%% code, although they have different calling conventions.

patch_closure_entry(Icode, ClosureInfo)->
  Arity = closure_info_arity(ClosureInfo), 
  %% ?msg("Arity ~w\n",[Arity]),
  {Args, Closure, FreeVars} = 
    split_params(Arity, hipe_icode:icode_params(Icode), []),
  [Start|_] = hipe_icode:icode_code(Icode),
  {_LMin, LMax} = hipe_icode:icode_label_range(Icode),
  hipe_gensym:set_label(icode,LMax+1),
  {_VMin, VMax} = hipe_icode:icode_var_range(Icode),
  hipe_gensym:set_var(icode,VMax+1),
  MoveCode = gen_get_free_vars(FreeVars, Closure,
			       hipe_icode:label_name(Start)),
  Icode1 = hipe_icode:icode_code_update(Icode, MoveCode ++
					hipe_icode:icode_code(Icode)),
  Icode2 = hipe_icode:icode_params_update(Icode1, Args),
  %% Arity - 1 since the original arity did not have the closure argument.
  Icode3 = hipe_icode:icode_closure_arity_update(Icode2, Arity-1),
  Icode3.

%%-----------------------------------------------------------------------

gen_get_free_vars(Vars, Closure, StartName) ->
  [hipe_icode:mk_new_label()] ++ 
    get_free_vars(Vars, Closure, 1, []) ++ [hipe_icode:mk_goto(StartName)].

get_free_vars([V|Vs], Closure, No, MoveCode) ->
  %% TempV = hipe_icode:mk_new_var(),
  get_free_vars(Vs, Closure, No+1,
		[%% hipe_icode:mk_move(TempV,hipe_icode:mk_const(No)),
		 hipe_icode:mk_primop([V], #closure_element{n=No}, [Closure])
		 |MoveCode]);
get_free_vars([],_,_,MoveCode) ->
  MoveCode.

%%-----------------------------------------------------------------------

split_params(1, [Closure|_OrgArgs] = Params, Args) ->
  {lists:reverse([Closure|Args]), Closure, Params};
split_params(1, [], Args) ->
  Closure = hipe_icode:mk_new_var(),
  {lists:reverse([Closure|Args]), Closure, []};
split_params(N, [ArgN|OrgArgs], Args) ->
  split_params(N-1, OrgArgs, [ArgN|Args]).

%%-----------------------------------------------------------------------

preprocess_code(ModuleCode) ->
  PatchedCode = patch_R7_funs(ModuleCode),
  ClosureInfo = find_closure_info(PatchedCode),
  {PatchedCode, ClosureInfo}.

%%-----------------------------------------------------------------------
%% Patches the "make_fun" BEAM instructions of R7 so that they also
%% contain the index that the BEAM loader generates for funs.
%% 
%% The index starts from 0 and is incremented by 1 for each make_fun
%% instruction encountered.
%%
%% Retained only for compatibility with BEAM code prior to R8.
%%
%% Temporarily, it also rewrites R8-PRE-RELEASE "make_fun2"
%% instructions, since their embedded indices don't work.
%%-----------------------------------------------------------------------

patch_R7_funs(ModuleCode) ->
  patch_make_funs(ModuleCode, 0).

patch_make_funs([FunCode0|Fs], FunIndex0) ->
  {PatchedFunCode,FunIndex} = patch_make_funs(FunCode0, FunIndex0, []),
  [PatchedFunCode|patch_make_funs(Fs, FunIndex)];
patch_make_funs([], _) -> [].

patch_make_funs([{make_fun,MFA,Magic,FreeVarNum}|Is], FunIndex, Acc) ->
  Patched = {patched_make_fun,MFA,Magic,FreeVarNum,FunIndex},
  patch_make_funs(Is, FunIndex+1, [Patched|Acc]);
patch_make_funs([{make_fun2,MFA,_BogusIndex,Magic,FreeVarNum}|Is], FunIndex, Acc) ->
  Patched = {patched_make_fun,MFA,Magic,FreeVarNum,FunIndex},
  patch_make_funs(Is, FunIndex+1, [Patched|Acc]);
patch_make_funs([I|Is], FunIndex, Acc) ->
  patch_make_funs(Is, FunIndex, [I|Acc]);
patch_make_funs([], FunIndex, Acc) ->
  {lists:reverse(Acc),FunIndex}.

%%-----------------------------------------------------------------------

find_mfa([{label,_}|Code]) ->
  find_mfa(Code);
find_mfa([{func_info,{atom,M},{atom,F},A}|_]) 
  when is_atom(M), is_atom(F), is_integer(A), 0 =< A, A =< 255 ->
  {M, F, A}.

%%-----------------------------------------------------------------------

%% Localize a particular function in a module
get_fun([[L, {func_info,{atom,M},{atom,F},A} | Is] | _], M,F,A) ->
  [L, {func_info,{atom,M},{atom,F},A} | Is];
get_fun([[_L1,_L2, {func_info,{atom,M},{atom,F},A} = MFA| _Is] | _], M,F,A) ->
  ?WARNING_MSG("Consecutive labels found; please re-create the .beam file~n", []),
  [_L1,_L2, MFA | _Is];
get_fun([_|Rest], M,F,A) ->
  get_fun(Rest, M,F,A).    

%%-----------------------------------------------------------------------
%% Takes a list of arguments and returns the constants of them into
%% fresh temporaries.  Return a triple consisting of a list of move
%% instructions, a list of proper icode arguments and the new environment.
%%-----------------------------------------------------------------------

get_constants_in_temps(Args, Env) ->
  get_constants_in_temps(Args, [], [], Env).

get_constants_in_temps([Arg|Args], Instrs, Temps, Env) ->
  case get_constant_in_temp(Arg, Env) of
    {none,ArgVar,Env1} ->
      get_constants_in_temps(Args, Instrs, [ArgVar|Temps], Env1);
    {Instr,Temp,Env1} ->
      get_constants_in_temps(Args, [Instr|Instrs], [Temp|Temps], Env1)
  end;
get_constants_in_temps([], Instrs, Temps, Env) ->
  {lists:reverse(Instrs), lists:reverse(Temps), Env}.

%%  If Arg is a constant then put Arg in a fresh temp!
get_constant_in_temp(Arg, Env) ->
  case is_var(Arg) of
    true ->  % Convert into Icode variable format before return
      {none, mk_var(Arg), Env};
    false -> % Create a new temp and move the constant into it
      Temp = mk_var(new),
      Const = trans_const(Arg),
      {hipe_icode:mk_move(Temp, Const), Temp, Env}
  end.

%%-----------------------------------------------------------------------
%% Makes a list of function arguments.
%%-----------------------------------------------------------------------

extract_fun_args(A) ->
  lists:reverse(extract_fun_args1(A)).

extract_fun_args1(0) ->
  [];
extract_fun_args1(1) ->
  [mk_var({r,0})];
extract_fun_args1(N) ->
  [mk_var({x,N-1}) | extract_fun_args1(N-1)].

%%-----------------------------------------------------------------------
%% Auxiliary translation for arguments of select_val & select_tuple_arity
%%-----------------------------------------------------------------------

trans_select_stuff(Reg, CaseList) ->
  SwVar = case is_var(Reg) of
	    true ->
	      mk_var(Reg);
	    false ->
	      trans_const(Reg)
	  end,
  CasePairs = trans_case_list(CaseList),
  {SwVar,CasePairs}.

trans_case_list([Symbol,{f,Lbl}|L]) ->
  [{trans_const(Symbol),map_label(Lbl)} | trans_case_list(L)];
trans_case_list([]) ->
  [].

%%-----------------------------------------------------------------------
%% Makes an Icode argument from a BEAM argument.
%%-----------------------------------------------------------------------

trans_arg(Arg) ->
  case is_var(Arg) of
    true ->
      mk_var(Arg);
    false ->
      trans_const(Arg)
  end.

%%-----------------------------------------------------------------------
%% Makes an Icode constant from a BEAM constant.
%%-----------------------------------------------------------------------

trans_const(Const) ->
  case Const of
    {atom,Atom} when is_atom(Atom) ->
      hipe_icode:mk_const(Atom);
    {integer,N} when is_integer(N) ->
      hipe_icode:mk_const(N);
    {float,Float} when is_float(Float) ->
      hipe_icode:mk_const(Float);
    {string,String} ->
      hipe_icode:mk_const(String);
    {literal,Literal} ->
      hipe_icode:mk_const(Literal);
    nil ->
      hipe_icode:mk_const([]);
    Int when is_integer(Int) ->
      hipe_icode:mk_const(Int)
  end.

%%-----------------------------------------------------------------------
%% Make an icode variable of proper type
%%   (Variables mod 5) =:= 0  are X regs
%%   (Variables mod 5) =:= 1  are Y regs
%%   (Variables mod 5) =:= 2  are FR regs
%%   (Variables mod 5) =:= 3  are new temporaries
%%   (Variables mod 5) =:= 4  are new register temporaries
%% Tell hipe_gensym to update its state for each new thing created!!
%%-----------------------------------------------------------------------

mk_var({r,0}) ->
  hipe_icode:mk_var(0);
mk_var({x,R}) when is_integer(R) ->
  V = 5*R,
  hipe_gensym:update_vrange(icode,V),
  hipe_icode:mk_var(V);
mk_var({y,R}) when is_integer(R) ->
  V = (5*R)+1,
  hipe_gensym:update_vrange(icode,V),
  hipe_icode:mk_var(V);
mk_var({fr,R}) when is_integer(R) ->
  V = (5*R)+2,
  hipe_gensym:update_vrange(icode,V),
  case get(hipe_inline_fp) of
    true ->
      hipe_icode:mk_fvar(V);
    _ ->
      hipe_icode:mk_var(V)
  end;
mk_var(new) ->
  T = hipe_gensym:new_var(icode),
  V = (5*T)+3,
  hipe_gensym:update_vrange(icode,V),
  hipe_icode:mk_var(V);
mk_var(reg) ->
  T = hipe_gensym:new_var(icode),
  V = (5*T)+4,
  hipe_gensym:update_vrange(icode,V),
  hipe_icode:mk_reg(V).

%%-----------------------------------------------------------------------
%% Make an icode label of proper type
%%   (Labels mod 2) =:= 0  are actually occuring in the BEAM code
%%   (Labels mod 2) =:= 1  are new labels generated by the translation
%%-----------------------------------------------------------------------

mk_label(L) when is_integer(L) ->
  LL = 2 * L,
  hipe_gensym:update_lblrange(icode, LL),
  hipe_icode:mk_label(LL);
mk_label(new) ->
  L = hipe_gensym:new_label(icode),
  LL = (2 * L) + 1,
  hipe_gensym:update_lblrange(icode, LL),
  hipe_icode:mk_label(LL).

%% Maps from the BEAM's labelling scheme to our labelling scheme.
%% See mk_label to understand how it works.

map_label(L) ->
  L bsl 1.  % faster and more type-friendly version of 2 * L

%%-----------------------------------------------------------------------
%% Returns the type of the given variables.
%%-----------------------------------------------------------------------

type({x,_}) ->
  var;
type({y,_}) ->
  var;
type({fr,_}) ->
  var;
type({atom,A}) when is_atom(A) ->
  #beam_const{value=A};
type(nil) ->
  #beam_const{value=[]};
type({integer,X}) when is_integer(X) ->
  #beam_const{value=X};
type({float,X}) when is_float(X) ->
  #beam_const{value=X};
type({literal,X}) ->
  #beam_const{value=X}.

%%-----------------------------------------------------------------------
%% Returns true iff the argument is a variable.
%%-----------------------------------------------------------------------

is_var({x,_}) ->
  true;
is_var({y,_}) ->
  true;
is_var({fr,_}) ->
  true;
is_var({atom,A}) when is_atom(A) ->
  false;
is_var(nil) ->
  false;
is_var({integer,N}) when is_integer(N) ->
  false;
is_var({float,F}) when is_float(F) ->
  false;
is_var({literal,_Literal}) ->
  false.

%%-----------------------------------------------------------------------
%% Fixes the code for catches by adding some code.
%%-----------------------------------------------------------------------

fix_catches(Code) ->
  fix_catches(Code, gb_trees:empty()).

%% We need to handle merged catch blocks, that is multiple 'catch' with
%% only one 'catch_end', or multiple 'try' with one 'try_case'. (Catch
%% and try can never be merged.) All occurrences of 'catch' or 'try'
%% with a particular fail-to label are assumed to only occur before the
%% corresponding 'catch_end'/'try_end' in the Beam code.

fix_catches([{'catch',N,Lbl},ContLbl|Code], HandledCatchLbls) ->
  fix_catch('catch',Lbl,ContLbl,Code,HandledCatchLbls,{catch_end,N});
fix_catches([{'try',N,Lbl},ContLbl|Code], HandledCatchLbls) ->
  fix_catch('try',Lbl,ContLbl,Code,HandledCatchLbls,{try_case,N});
fix_catches([Instr|Code], HandledCatchLbls) ->
  [Instr|fix_catches(Code, HandledCatchLbls)];
fix_catches([], _HandledCatchLbls) ->
  [].

fix_catch(Type, Lbl, ContLbl, Code, HandledCatchLbls, Instr) ->
  TLbl = {Type, Lbl},
  case gb_trees:lookup(TLbl, HandledCatchLbls) of
    {value, Catch} when is_integer(Catch) ->
      NewCode = fix_catches(Code, HandledCatchLbls),
      Cont = hipe_icode:label_name(ContLbl),
      [hipe_icode:mk_begin_try(Catch,Cont),ContLbl | NewCode];
    none ->
      OldCatch = map_label(Lbl),
      OldCatchLbl = hipe_icode:mk_label(OldCatch),
      {CodeToCatch,RestOfCode} = split_code(Code,OldCatchLbl,Instr),
      NewCatchLbl = mk_label(new),
      NewCatch = hipe_icode:label_name(NewCatchLbl),
      %% The rest of the code cannot contain catches with the same label.
      RestOfCode1 = fix_catches(RestOfCode, HandledCatchLbls),
      %% The catched code *can* contain more catches with the same label.
      NewHandledCatchLbls = gb_trees:insert(TLbl, NewCatch, HandledCatchLbls),
      CatchedCode = fix_catches(CodeToCatch, NewHandledCatchLbls),
      %% The variables which will get the tag, value, and trace.
      Vars = [mk_var({r,0}), mk_var({x,1}), mk_var({x,2})],
      Cont = hipe_icode:label_name(ContLbl),
      [hipe_icode:mk_begin_try(NewCatch,Cont), ContLbl]
	++ CatchedCode
	++ [mk_label(new), % dummy label before the goto
	    hipe_icode:mk_goto(OldCatch),  % normal execution path
	    NewCatchLbl,  % exception handing enters here
	    hipe_icode:mk_begin_handler(Vars)]
        ++ catch_handler(Type, Vars, OldCatchLbl)
	++ RestOfCode1  % back to normal execution
  end.

catch_handler('try', _Vars, OldCatchLbl) ->
  %% A try just falls through to the old fail-to label which marked the
  %% start of the try_case block. All variables are set up as expected.
  [OldCatchLbl];
catch_handler('catch', [TagVar,ValueVar,TraceVar], OldCatchLbl) ->
  %% This basically implements a catch as a try-expression. We must jump
  %% to the given end label afterwards so we don't pass through both the
  %% begin_handler and the end_try.
  ContLbl = mk_label(new),
  Cont = hipe_icode:label_name(ContLbl),
  ThrowLbl = mk_label(new),
  NoThrowLbl = mk_label(new),
  ExitLbl = mk_label(new),
  ErrorLbl = mk_label(new),
  Dst = mk_var({r,0}),
  [hipe_icode:mk_if('=:=', [TagVar, hipe_icode:mk_const('throw')],
		    hipe_icode:label_name(ThrowLbl),
		    hipe_icode:label_name(NoThrowLbl)),
   ThrowLbl,
   hipe_icode:mk_move(Dst, ValueVar),   
   hipe_icode:mk_goto(Cont),
   NoThrowLbl,
   hipe_icode:mk_if('=:=', [TagVar, hipe_icode:mk_const('exit')],
		    hipe_icode:label_name(ExitLbl),
		    hipe_icode:label_name(ErrorLbl)),
   ExitLbl,
   hipe_icode:mk_primop([Dst],mktuple,[hipe_icode:mk_const('EXIT'),
				       ValueVar]),
   hipe_icode:mk_goto(Cont),
   ErrorLbl,
   %% We use the trace variable to hold the symbolic trace. Its previous
   %% value is just that in p->ftrace, so get_stacktrace() works fine.
   hipe_icode:mk_call([TraceVar],erlang,get_stacktrace,[],remote),
   hipe_icode:mk_primop([ValueVar],mktuple, [ValueVar, TraceVar]),
   hipe_icode:mk_goto(hipe_icode:label_name(ExitLbl)),
   OldCatchLbl,  % normal execution paths must go through end_try
   hipe_icode:mk_end_try(),
   hipe_icode:mk_goto(Cont),
   ContLbl].

%% Note that it is the fail-to label that is the important thing, but
%% for 'catch' we want to make sure that the label is followed by the
%% 'catch_end' instruction - if it is not, we might have a real problem.
%% Checking that a 'try' label is followed by 'try_case' is not as
%% important, but we get that as a bonus.

split_code([First|Code], Label, Instr) ->
  split_code(Code, Label, Instr, First, []).

split_code([Instr|Code], Label, Instr, Prev, As) when Prev =:= Label ->
  split_code_final(Code, As);  % drop both label and instruction
split_code([Other|_Code], Label, Instr, Prev, _As) when Prev =:= Label ->
  ?EXIT({missing_instr_after_label, Label, Instr, [Other, Prev | _As]});
split_code([Other|Code], Label, Instr, Prev, As) ->
  split_code(Code, Label, Instr, Other, [Prev|As]);
split_code([], _Label, _Instr, Prev, As) ->
  split_code_final([], [Prev|As]).

split_code_final(Code, As) ->
  {lists:reverse(As), Code}.

%%-----------------------------------------------------------------------
%% Fixes fallthroughs
%%-----------------------------------------------------------------------

fix_fallthroughs([]) ->
  [];
fix_fallthroughs([I|Is]) ->
  fix_fallthroughs(Is, I, []).

fix_fallthroughs([I1|Is], I0, Acc) ->
  case hipe_icode:is_label(I1) of
    false ->
      fix_fallthroughs(Is, I1, [I0 | Acc]);
    true ->
      case hipe_icode:is_branch(I0) of
	true ->
	  fix_fallthroughs(Is, I1, [I0 | Acc]);
	false ->
	  %% non-branch before label - insert a goto
	  Goto = hipe_icode:mk_goto(hipe_icode:label_name(I1)),
	  fix_fallthroughs(Is, I1, [Goto, I0 | Acc])
      end
  end;
fix_fallthroughs([], I, Acc) ->
  lists:reverse([I | Acc]).

%%-----------------------------------------------------------------------
%% Removes the code between a fail instruction and the closest following
%% label.
%%-----------------------------------------------------------------------

-spec remove_dead_code(icode_instrs()) -> icode_instrs().
remove_dead_code([I|Is]) ->
  case I of
    #icode_fail{} ->
      [I|remove_dead_code(skip_to_label(Is))];
    _ ->
      [I|remove_dead_code(Is)]
  end;
remove_dead_code([]) ->
  [].

%% returns the instructions from the closest label
-spec skip_to_label(icode_instrs()) -> icode_instrs().
skip_to_label([I|Is] = Instrs) ->
  case I of
    #icode_label{} -> Instrs;
    _ -> skip_to_label(Is)
  end;
skip_to_label([]) ->
  [].

%%-----------------------------------------------------------------------
%% This needs to be extended in case new architectures are added.
%%-----------------------------------------------------------------------

resolve_native_endianess(Flags) ->
  case {Flags band 16#10, hipe_rtl_arch:endianess()} of
    {16#10, big} ->
      Flags band 5;
    {16#10, little} ->
      (Flags bor 2) band 7;  
    _ ->
      Flags band 7
  end.

%%-----------------------------------------------------------------------
%% Potentially useful for debugging.
%%-----------------------------------------------------------------------

pp_beam(BeamCode, Options) ->
  case proplists:get_value(pp_beam, Options) of
    true ->
      pp(BeamCode);
    {file,FileName} ->
      {ok,File} = file:open(FileName, [write]),
      pp(File, BeamCode);
    _ -> %% includes "false" case
      ok
  end.

pp(Code) ->
  pp(standard_io, Code).

pp(Stream, []) ->
  case Stream of  %% I am not sure whether this is necessary
    standard_io -> ok;
    _ -> ok = file:close(Stream)
  end;
pp(Stream, [FunCode|FunCodes]) ->
  pp_mfa(Stream, FunCode),
  put_nl(Stream),
  pp(Stream, FunCodes).

pp_mfa(Stream, FunCode) ->
  lists:foreach(fun(Instr) -> print_instr(Stream, Instr) end, FunCode).

print_instr(Stream, {label,Lbl}) ->
  io:format(Stream, "  label ~p:\n", [Lbl]);
print_instr(Stream, Op) ->
  io:format(Stream, "    ~p\n", [Op]).

put_nl(Stream) ->
  io:format(Stream, "\n", []).

%%-----------------------------------------------------------------------
%% Handling of environments -- used to process local tail calls.
%%-----------------------------------------------------------------------

%% Construct an environment
env__mk_env(M, F, A, Entry) ->
  #environment{mfa={M,F,A}, entry=Entry}.

%% Get current MFA
env__get_mfa(#environment{mfa=MFA}) -> MFA.

%% Get entry point of the current function
env__get_entry(#environment{entry=EP}) -> EP.

%%-----------------------------------------------------------------------
