path: root/lib/hipe/main/hipe.erl

%% -*- erlang-indent-level: 2 -*-
%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2001-2015. All Rights Reserved.
%%
%% Licensed under the Apache License, Version 2.0 (the "License");
%% you may not use this file except in compliance with the License.
%% You may obtain a copy of the License at
%%
%%     http://www.apache.org/licenses/LICENSE-2.0
%%
%% Unless required by applicable law or agreed to in writing, software
%% distributed under the License is distributed on an "AS IS" BASIS,
%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
%% See the License for the specific language governing permissions and
%% limitations under the License.
%%
%% %CopyrightEnd%
%%
%% ====================================================================
%% Copyright (c) 1998 by Erik Johansson.  All Rights Reserved 
%% ====================================================================
%%  Filename : hipe.erl
%%  Module   : hipe
%%  Purpose  :  
%%  Notes    : 
%%  History  : * 1998-01-28 Erik Johansson ([email protected]): Created.
%% ====================================================================
%% @doc This is the direct interface to the HiPE compiler.
%%
%% <h3>Normal use</h3>
%%
%% <p>The normal way to native-compile an Erlang module using HiPE is to
%% include the atom <code>native</code> in the Erlang compiler options,
%% as in:
%%
%% <pre>    1> c(my_module, [native]).</pre></p>
%%
%% <p>Options to the HiPE compiler are then passed as follows:
%%
%% <pre>    1> c(my_module, [native,{hipe,Options}]).</pre></p>
%%
%% <p>For on-line help in the Erlang shell, call <a
%% href="#help-0"><code>hipe:help()</code></a>. Details on HiPE compiler
%% options are given by <a
%% href="#help_options-0"><code>hipe:help_options()</code></a>.</p>
%%
%% <h3>Using the direct interface - for advanced users only</h3>
%%
%% To compile a module to native code and automatically load the code
%% into memory, call <a href="#c-1"><code>hipe:c(Module)</code></a> or <a
%% href="#c-2"><code>hipe:c(Module, Options)</code></a>. Note that all
%% options are specific to the HiPE compiler. See the <a
%% href="#index">function index</a> for other compiler functions.
%%
%% <h3>Main Options</h3>
%%
%% Options are processed in the order they appear in the list; an
%% early option will shadow a later one.
%% <dl>
%%   <dt><code>o0, 'O0', o1, 'O1', o2, 'O2', o3, 'O3'</code></dt>
%%     <dd>Set optimization level (default 2).</dd>
%%
%%   <dt><code>load</code></dt>
%%     <dd>Automatically load the code into memory after compiling.</dd>
%%
%%   <dt><code>time</code></dt>
%%     <dd>Reports the compilation times for the different stages
%%     of the compiler. Call <a
%%     href="#help_option-1"><code>hipe:help_option(time)</code></a> for
%%     details.</dd>
%%
%%   <dt><code>{timeout, Time}</code></dt>
%%     <dd>Sets the time the compiler is allowed to use for the
%%     compilation. <code>Time</code> is time in ms or the atom
%%     <code>infinity</code> (the default).</dd>
%%
%%   <dt><code>verbose</code></dt>
%%     <dd>Make the HiPE compiler output information about what it is
%%     being done.</dd>
%% </dl>
%% 
%% <h3>Advanced Options</h3>
%%
%% Note: You can also specify <code>{Option, false}</code> to turn a
%% particular option off, or <code>{Option, true}</code> to force it on.
%% Boolean-valued (<code>true</code>/<code>false</code>) options also
%% have negative-form aliases, e.g. <code>no_load</code> = <code>{load,
%% false}</code>.
%%
%% <p><dl>
%%   <dt><code>debug</code></dt>
%%     <dd>Outputs internal debugging information during
%%     compilation.</dd>
%%
%%   <dt><code>icode_ssa_copy_prop</code></dt>
%%     <dd>Performs copy propagation on the SSA form on the Icode
%%     level.</dd>
%%
%%   <dt><code>icode_ssa_const_prop</code></dt>
%%     <dd>Performs sparse conditional constant propagation on the SSA
%%     form on the Icode level.</dd>
%%
%%   <dt><code>icode_ssa_struct_reuse</code></dt>
%%     <dd>Tries to factor out identical tuple and list constructions
%%     on the Icode level.</dd>
%%
%%   <dt><code>icode_type</code></dt>
%%     <dd>Simplifies the code by employing type analysis and propagation
%%     on the Icode level.</dd>
%%
%%   <dt><code>icode_range</code></dt>
%%     <dd>Performs integer range analysis on the Icode level.</dd>
%%
%%   <dt><code>pp_all</code></dt>
%%     <dd>Equivalent to <code>[pp_beam, pp_icode, pp_rtl,
%%     pp_native]</code>.</dd>
%%
%%   <dt><code>pp_asm</code></dt>
%%     <dd>Prints the assembly listing with addresses and bytecode.
%%     Currently available for x86 only.</dd>
%%
%%   <dt><code>pp_beam, {pp_beam, {file, File}}</code></dt>
%%     <dd>Display the input Beam code to stdout or file.</dd>
%%
%%   <dt><code>pp_icode, {pp_icode, {file, File}},
%%       {pp_icode, {only, Functions}}</code></dt>
%%     <dd>Pretty-print Icode intermediate code to stdout or file.</dd>
%%
%%   <dt><code>pp_native, {pp_native, {file, File}},
%%       {pp_native, {only, Functions}}</code></dt>
%%     <dd>Pretty-print native code to stdout or file.</dd>
%%
%%   <dt><code>pp_opt_icode, {pp_opt_icode, {file, File}},
%%       {pp_opt_icode, {only, Functions}}</code></dt>
%%     <dd>Pretty-print optimized Icode to stdout or file.</dd>
%%
%%   <dt><code>pp_rtl, {pp_rtl, {file, File}},
%%       {pp_rtl, {only, Functions}}</code></dt>
%%     <dd>Pretty-print RTL intermediate code to stdout or file.</dd>
%%
%%   <dt><code>regalloc</code></dt>
%%     <dd>Select register allocation algorithm. Used as
%%     <code>{regalloc, Method}</code>.
%%
%%     <p><code>Method</code> is one of the following:
%%     <ul>
%%       <li><code>naive</code>: spills everything (for debugging and
%%       testing only).</li>
%%       <li><code>linear_scan</code>: fast compilation; not so good if
%%       only few registers available.</li>
%%       <li><code>graph_color</code>: slower, but gives better
%%       performance.</li>
%%       <li><code>coalescing</code>: tries hard to use registers; can be
%%	 very slow, but typically results in code with best performance.</li>
%%     </ul></p></dd>
%%
%%   <dt><code>remove_comments</code></dt>
%%     <dd>Remove comments from intermediate code.</dd>
%%
%%   <dt><code>rtl_ssa_const_prop</code></dt>
%%     <dd>Performs sparse conditional constant propagation on the SSA
%%     form on the RTL level. </dd>
%%
%%   <dt><code>rtl_lcm</code></dt>
%%     <dd>Lazy Code Motion on RTL.</dd>
%%
%%   <dt><code>rtl_ssapre</code></dt>
%%     <dd>Lazy Partial Redundancy Elimination on RTL (SSA level).</dd>
%%
%%   <dt><code>use_indexing</code></dt>
%%     <dd>Use indexing for multiple-choice branch selection.</dd>
%%
%%   <dt><code>use_callgraph</code></dt>
%%     <dd>Use a static call graph for determining the order in which
%%         the functions of a module should be compiled (in reversed 
%%         topological sort order).</dd>
%% </dl></p>
%%
%% <h3>Debugging Options</h3>
%% (May require that some modules have been
%% compiled with the <code>DEBUG</code> flag.)
%% <dl>
%%   <dt><code>rtl_show_translation</code></dt>
%%     <dd>Prints each step in the translation from Icode to RTL</dd>
%% </dl>
%%
%% @end
%% ====================================================================

-module(hipe).

-export([c/1,
	 c/2,
 	 f/1,
 	 f/2,
	 compile/1,
	 compile/2,
	 compile/4,
	 compile_core/4,
 	 file/1,
 	 file/2,
        llvm_support_available/0,
	 load/1,
	 help/0,
	 help_hiper/0,
	 help_options/0,
	 help_option/1,
	 help_debug_options/0,
	 version/0,
	 erts_checksum/0]).

-ifndef(DEBUG).
-define(DEBUG,true).
-endif.

-include("hipe.hrl").
-include("../../compiler/src/beam_disasm.hrl").
-include("../rtl/hipe_literals.hrl").

%%-------------------------------------------------------------------
%% Basic type declaration for exported functions of the 'hipe' module
%%-------------------------------------------------------------------

-type mod() :: atom().
-type f_unit() :: mod() | binary().
-type ret_rtl() :: [_].
-type c_ret() :: {'ok', mod()} | {'error', term()} |
                 {'ok', mod(), ret_rtl()}. %% The last for debugging only
-type compile_file() :: atom() | string() | binary().
-type compile_ret() :: {hipe_architecture(), binary()} | list().

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

-define(COMPILE_DEFAULTS, [o2]).
-define(DEFAULT_TIMEOUT, infinity).

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

%% @spec load(Mod) -> {module, Mod} | {error, Reason}
%%     Mod = mod()
%%     Reason = term()
%% 
%% @doc Like load/2, but tries to locate a BEAM file automatically.
%%
%% @see load/2

-spec load(Mod) -> {'module', Mod} | {'error', term()} when Mod :: mod().

load(Mod) ->
  load(Mod, beam_file(Mod)).

%% @spec load(Mod, BeamFileName) -> {module, Mod} | {error, Reason}
%%     Mod = mod()
%%     Reason = term()
%%     BeamFileName = string()
%%     filename() = term()
%%
%% @type mod() = atom(). A module name.
%% 
%% @doc User interface for loading code into memory. The code can be
%% given as a native code binary or as the file name of a BEAM file
%% which should contain a native-code chunk. If only the module name is
%% given (see <code>load/1</code>), the BEAM file is located
%% automatically.
%%
%% @see load/1

-spec load(Mod, string()) -> {'module', Mod} | {'error', term()}
				   when Mod :: mod().

load(Mod, BeamFileName) when is_list(BeamFileName) ->
  Architecture = erlang:system_info(hipe_architecture),
  ChunkName = hipe_unified_loader:chunk_name(Architecture),
  case beam_lib:chunks(BeamFileName, [ChunkName]) of
    {ok,{_,[{_,Bin}]}} when is_binary(Bin) -> do_load(Mod, Bin, BeamFileName);
    Error -> {error, Error}
  end.

%% @spec c(Name) -> {ok, Name} | {error, Reason}
%%       Name = mod()
%%       Reason = term()
%%
%% @equiv c(Name, [])

-spec c(mod()) -> c_ret().

c(Name) ->
  c(Name, []).

%% @spec c(Name, options()) -> {ok, Name} | {error, Reason}
%%     Name = mod()
%%     options() = [option()]
%%     option() = term()
%%     Reason = term()
%%
%% @type fun() = atom(). A function identifier.
%%
%% @type arity() = integer(). A function arity; always nonnegative.
%% 
%% @doc User-friendly native code compiler interface. Reads BEAM code
%% from the corresponding "Module<code>.beam</code>" file in the
%% system path, and compiles the whole module to native code. By
%% default, the compiled code is loaded directly. See above for
%% documentation of options.
%%
%% @see c/1
%% @see c/3
%% @see f/2
%% @see compile/2

-spec c(mod(), comp_options()) -> c_ret().

c(Name, Options) ->
  c(Name, beam_file(Name), Options).

%% @spec c(Name, File, options()) -> {ok, Name} | {error, Reason}
%%     Name = mod()
%%     File = filename() | binary()
%%     Reason = term()
%%
%% @doc Like <code>c/2</code>, but reads BEAM code from the specified
%% <code>File</code>.
%%
%% @see c/2
%% @see f/2

c(Name, File, Opts) ->
  Opts1 = user_compile_opts(Opts),
  case compile(Name, File, Opts1) of
    {ok, Res} ->
      case proplists:get_bool(to_rtl, Opts1) of
	true -> {ok, Name, Res};
	false -> {ok, Name}
      end;
    Other ->
      Other
  end.

%% @spec f(File) -> {ok, Name} | {error, Reason}
%%     File = filename() | binary()
%%     Name = mod()
%%     Reason = term()
%%
%% @equiv f(File, [])

-spec f(f_unit()) -> {'ok', mod()} | {'error', term()}.

f(File) ->
  f(File, []).

%% @spec f(File, options()) -> {ok, Name} | {error, Reason}
%%     File = filename() | binary()
%%     Name = mod()
%%     Reason = term()
%%
%% @doc Like <code>c/3</code>, but takes the module name from the
%% specified <code>File</code>.
%%
%% @see c/3

-spec f(f_unit(), comp_options()) -> {'ok', mod()} | {'error', term()}.

f(File, Opts) ->
  case file(File, user_compile_opts(Opts)) of
    {ok, Name, _} ->
      {ok, Name};
    Other ->
      Other
  end.

-define(USER_DEFAULTS, [load]).

user_compile_opts(Opts) ->
  Opts ++ ?USER_DEFAULTS.


%% @spec compile(Name) -> {ok, {Target,Binary}} | {error, Reason}
%%       Name = mod()
%%       Binary = binary()
%%       Reason = term()
%% 
%% @equiv compile(Name, [])

-spec compile(mod()) -> {'ok', compile_ret()} | {'error', term()}.

compile(Name) ->
  compile(Name, []).

%% @spec compile(Name, options()) -> {ok, {Target,Binary}} | {error, Reason}
%%       Name = mod()
%%       Binary = binary()
%%       Reason = term()
%%
%% @doc Direct compiler interface, for advanced use. This just
%% compiles the module, reading BEAM code from the corresponding
%% "Module<code>.beam</code>" file in the system path.  Returns
%% <code>{ok, Binary}</code> if successful, or <code>{error,
%% Reason}</code> otherwise. By default, it does <em>not</em> load the
%% binary to memory (the <code>load</code> option can be used to
%% activate automatic loading). <code>File</code> can be either a file
%% name or a binary containing the BEAM code for the module.
%%
%% @see c/2
%% @see compile/1
%% @see compile/3
%% @see file/2
%% @see load/2

-spec compile(mod(), comp_options()) -> {'ok', compile_ret()} | {'error', _}.

compile(Name, Options) ->
  compile(Name, beam_file(Name), Options).

-spec beam_file(mod()) -> string().

beam_file(Module) when is_atom(Module) ->
  case code:which(Module) of
    non_existing ->
      ?error_msg("Cannot find ~w.beam file.",[Module]),
      ?EXIT({cant_find_beam_file,Module});
    File -> % string()
      File
  end.

%% @spec compile(Name, File, options()) ->
%%           {ok, {Target, Binary}} | {error, Reason}
%%       Name = mod()
%%       File = filename() | binary()
%%       Binary = binary()
%%       Reason = term()
%% 
%% @doc Like <code>compile/2</code>, but reads BEAM code from the
%% specified <code>File</code>.
%%
%% @see compile/2

-spec compile(mod(), compile_file(), comp_options()) ->
	 {'ok', compile_ret()} | {'error', term()}.

compile(Name, File, Opts0) when is_atom(Name) ->
  Opts = expand_kt2(Opts0),
  case proplists:get_value(core, Opts) of
    true when is_binary(File) ->
      ?error_msg("Cannot get Core Erlang code from BEAM binary.",[]),
      ?EXIT({cant_compile_core_from_binary});
    true ->
      case filename:find_src(filename:rootname(File, ".beam")) of
	{error, _} ->
	  ?error_msg("Cannot find source code for ~p.",[File]),
	  ?EXIT({cant_find_source_code});
	{Source, CompOpts} ->
	  CoreOpts = [X || X = {core_transform, _} <- Opts],
	  %%io:format("Using: ~w\n", [CoreOpts]),
	  case compile:file(Source, CoreOpts ++ [to_core, binary|CompOpts]) of
	    {ok, _, Core} ->
	      compile_core(Name, Core, File, Opts);
	    Error ->
	      ?error_msg("Error compiling ~p:\n~p.",[File, Error]),
	      ?EXIT({cant_compile_source_code})
	  end
      end;
    {src_file, Source} ->
      CoreOpts1 = [X || X = {core_transform, _} <- Opts],
      CoreOpts2 = [report_errors, to_core, binary, {i,"../include"}|CoreOpts1],
      %% io:format("Using: ~w\n", [CoreOpts2]),
      case compile:file(Source, CoreOpts2) of
	{ok, _, Core} ->
	  compile_core(Name, Core, File, Opts);
	Error ->
	  ?error_msg("Error compiling ~p:\n~p\n",[Source, Error]),
	  ?EXIT({cant_compile_source_code, Error})
      end;
    Other when Other =:= false; Other =:= undefined ->
      DisasmFun = fun (_) -> disasm(File) end,
      IcodeFun = fun (Code, Opts_) ->
		     get_beam_icode(Name, Code, File, Opts_)
		 end,
      run_compiler(Name, DisasmFun, IcodeFun, Opts)
  end.

-spec compile_core(mod(), cerl:c_module(), compile_file(), comp_options()) ->
	 {'ok', compile_ret()} | {'error', term()}.

compile_core(Name, Core0, File, Opts) ->
  Core = cerl:from_records(Core0),
  compile(Name, Core, File, Opts).

%% @spec compile(Name, Core, File, options()) ->
%%           {ok, {Target, Binary}} | {error, Reason}
%%       Name = mod()
%%       Core = coreErlang() | []
%%       File = filename() | binary()
%%       Binary = binary()
%%       Reason = term()
%% 
%% @doc Like <code>compile/3</code>, but unless <code>Core</code> is
%% <code>[]</code>, low-level code is generated from the given Core
%% Erlang code instead of from the BEAM code.
%%
%% <p>Note that only whole modules can be compiled with this
%% function.</p>
%%
%% @see compile/3

-spec compile(mod(), cerl:c_module() | [], compile_file(), comp_options()) ->
	 {'ok', compile_ret()} | {'error', term()}.

compile(Name, [], File, Opts) ->
  compile(Name, File, Opts);
compile(Name, Core, File, Opts) when is_atom(Name) ->
  DisasmFun = fun (_) -> {false, []} end,
  IcodeFun = fun (_, Opts) ->
		 get_core_icode(Name, Core, File, Opts)
	     end,
  run_compiler(Name, DisasmFun, IcodeFun, Opts).

%% @spec file(File) -> {ok, Name, {Target, Binary}} | {error, Reason}
%%       File = filename() | binary()
%%       Name = mod() | mfa()
%%       Binary = binary()
%%       Reason = term()
%% 
%% @equiv file(File, [])

-spec file(Mod) -> {'ok', Mod, compile_ret()} | {'error', term()}
		     when Mod :: mod().

file(File) ->
  file(File, []).

%% @spec file(File, options()) -> {ok, Name, {Target,Binary}} | {error, Reason}
%%       File = filename()
%%       Name = mod() | mfa()
%%       Binary = binary()
%%       Reason = term()
%% 
%% @doc Like <code>compile/2</code>, but takes the module name from the
%% specified <code>File</code>. Returns both the name and the final
%% binary if successful.
%%
%% @see file/1
%% @see compile/2

-spec file(Mod, comp_options()) -> {'ok', Mod, compile_ret()}
				|  {'error', term()}
				     when Mod :: mod().
file(File, Options) when is_atom(File) ->
  case beam_lib:info(File) of
    L when is_list(L) ->
      {module, Mod} = lists:keyfind(module, 1, L),
      case compile(Mod, File, Options) of
	{ok, CompRet} ->
	  {ok, Mod, CompRet};
	Other ->
	  Other
      end;
    Error ->
      Error
  end.


%%-----------------------------------------------------------------------
%% The rest are internal functions:
%%-----------------------------------------------------------------------

%% @doc
%% Get BEAM code from `.beam' files or directly from binaries.
%%   File is either a file name or a binary containing the BEAM code.

disasm(File) ->
  case beam_disasm:file(File) of
    #beam_file{labeled_exports = LabeledExports,
	       compile_info = CompInfo,
	       code = BeamCode} ->
      CompOpts = proplists:get_value(options, CompInfo, []),
      HCompOpts = case lists:keyfind(hipe, 1, CompOpts) of
		    {hipe, L} when is_list(L) -> L;
		    {hipe, X} -> [X];
		    _ -> []
		  end,
      Exports = fix_beam_exports(LabeledExports),
      {{BeamCode, Exports}, HCompOpts};
    {error, _Mod, Error} ->
      io:format("~s\n", [beam_lib:format_error(Error)]),
      ?EXIT(no_beam_code)
  end.

fix_beam_exports(BeamExports) ->
  fix_beam_exports(BeamExports, []).

fix_beam_exports([{F,A,_}|BeamExports], Exports) ->
  fix_beam_exports(BeamExports, [{F,A} | Exports]);
fix_beam_exports([], Exports) ->
  Exports.

get_beam_icode(Mod, {BeamCode, Exports}, File, Options) ->
  ?option_time({ok, Icode} =
	       (catch {ok, hipe_beam_to_icode:module(BeamCode, Options)}),
	       "BEAM-to-Icode", Options),
  BeamBin = get_beam_code(File),
  {{Mod, Exports, Icode}, BeamBin}.

get_core_icode(Mod, Core, File, Options) ->
  ?option_time({ok, Icode} =
	       (catch {ok, cerl_to_icode:module(Core, Options)}),
	       "BEAM-to-Icode", Options),
  NeedBeamCode = not proplists:get_bool(load, Options),
  BeamBin = 
    case NeedBeamCode of
      true -> [];
      false -> get_beam_code(File)
    end,
  Exports = [cerl:var_name(V) || V <- cerl:module_exports(Core)],
  {{Mod, Exports, Icode}, BeamBin}.

get_beam_code(Bin) when is_binary(Bin) -> Bin;
get_beam_code(FileName) ->
  case erl_prim_loader:get_file(FileName) of
    {ok,Bin,_} ->
      Bin;
    error ->
      ?EXIT(no_beam_file)
  end.


%% ---------------------------------------------------------------------
%% All compilations go through this function. Note that it receives only
%% "basic" options. Name is just used for verbosity. The DisasmFun and
%% IcodeFun only collect the Icode; most of the real work is done in the
%% 'finalize' function.

run_compiler(Name, DisasmFun, IcodeFun, Opts0) ->
  Opts = expand_basic_options(Opts0 ++ ?COMPILE_DEFAULTS),
  ?when_option(verbose, Opts, ?debug_msg("Compiling: ~p\n",[Name])),
  ?option_start_time("Compile", Opts),
  Res = run_compiler_1(DisasmFun, IcodeFun, Opts),
  ?option_stop_time("Compile", Opts),
  Res.

run_compiler_1(DisasmFun, IcodeFun, Options) ->
  Parent = self(),
  {trap_exit,TrapExit} = process_info(Parent, trap_exit),
  %% Spawn a compilation process CompProc. In case this process gets
  %% killed, the trap_exit flag is restored to that of the Parent process.
  process_flag(trap_exit, true),
  CompProc = spawn_link(fun () ->
			    %% Compiler process
			    set_architecture(Options),
			    pre_init(Options),
			    %% The full option expansion is not done
			    %% until the DisasmFun returns.
			    {Code, CompOpts} = DisasmFun(Options),
			    Opts0 = expand_options(Options ++ CompOpts,
                                                   get(hipe_target_arch)),
                            Opts =
                             case proplists:get_bool(to_llvm, Opts0) andalso
                                 not llvm_support_available() of
                               true ->
                                 ?error_msg("No LLVM version 3.4 or greater "
                                            "found in $PATH; aborting "
                                            "native code compilation.\n", []),
                                 ?EXIT(cant_find_required_llvm_version);
                               false ->
                                 Opts0
                             end,
			    check_options(Opts),
			    ?when_option(verbose, Options,
					 ?debug_msg("Options: ~p.\n",[Opts])),
			    init(Opts),
			    {Icode, WholeModule} = IcodeFun(Code, Opts),
			    CompRes = compile_finish(Icode, WholeModule, Opts),
			    compiler_return(CompRes, Parent)
			end),
  Timeout = case proplists:get_value(timeout, Options) of
	      N when is_integer(N), N >= 0 -> N;
	      undefined -> ?DEFAULT_TIMEOUT;
	      infinity -> infinity;
	      Other ->
		?WARNING_MSG("Bad timeout value: ~P\n"
			     "Using default timeout limit.\n",	
			     [Other, 5]),
		?DEFAULT_TIMEOUT
	    end,
  receive
    {'EXIT', CompProc, normal} -> ok;
    {'EXIT', CompProc, Reason} -> exit(Reason)
  after Timeout ->
      %% Kill the compilation process
      exit(CompProc, kill),
      receive {'EXIT', CompProc, _} -> ok end,
      flush(),
      ?error_msg("ERROR: Compilation timed out.\n",[]),
      exit(timed_out)
  end,
  Result = receive {CompProc, Res} -> Res end,
  process_flag(trap_exit, TrapExit),
  Result.

flush() ->
  receive
    _ -> flush()
  after 0 ->
      ok
  end.

compiler_return(Res, Client) ->
  Client ! {self(), Res}.

compile_finish({Mod, Exports, Icode}, WholeModule, Options) ->
  Res = finalize(Icode, Mod, Exports, WholeModule, Options),
  post(Res, Icode, Options).


%% -------------------------------------------------------------------------
%% finalize/5
%% compiles, assembles, and optionally loads a list of `{MFA, Icode}' pairs,
%% and returns `{ok, {TargetArch, Binary}}' or `{error, Reason, Stack}'.

finalize(OrigList, Mod, Exports, WholeModule, Opts) ->
  List = icode_multret(OrigList, Mod, Opts, Exports),
  {T1Compile,_} = erlang:statistics(runtime),
  CompiledCode =
    case proplists:get_value(use_callgraph, Opts) of
      true -> 
	%% Compiling the functions bottom-up by using a call graph
	CallGraph = hipe_icode_callgraph:construct(List),
	OrdList = hipe_icode_callgraph:to_list(CallGraph),
	finalize_fun(OrdList, Exports, Opts);
      _ -> 
	%% Compiling the functions bottom-up by reversing the list
	OrdList = lists:reverse(List),
	finalize_fun(OrdList, Exports, Opts)
    end,
  {T2Compile,_} = erlang:statistics(runtime),
  ?when_option(verbose, Opts,
	       ?debug_msg("Compiled ~p in ~.2f s\n",
			  [Mod,(T2Compile-T1Compile)/1000])),
  case proplists:get_bool(to_rtl, Opts) of
    true ->
      {ok, CompiledCode};
    false ->
      Closures =
	[MFA || {MFA, Icode} <- List,
		hipe_icode:icode_is_closure(Icode)],
      {T1,_} = erlang:statistics(runtime),
      ?when_option(verbose, Opts, ?debug_msg("Assembling ~w",[Mod])),
      try assemble(CompiledCode, Closures, Exports, Opts) of
	Bin ->
	  {T2,_} = erlang:statistics(runtime),
	  ?when_option(verbose, Opts,
		       ?debug_untagged_msg(" in ~.2f s\n",
					   [(T2-T1)/1000])),
	  {module,Mod} = maybe_load(Mod, Bin, WholeModule, Opts),
	  TargetArch = get(hipe_target_arch),
	  {ok, {TargetArch,Bin}}
      catch
	error:Error ->
	  {error,Error,erlang:get_stacktrace()}
      end
  end.

finalize_fun(MfaIcodeList, Exports, Opts) ->
  case proplists:get_value(concurrent_comp, Opts) of
    FalseVal when (FalseVal =:= undefined) orelse (FalseVal =:= false) ->
      NoServers = #comp_servers{pp_server = none, range = none, type = none},
      [finalize_fun_sequential(MFAIcode, Opts, NoServers)
       || {_MFA, _Icode} = MFAIcode <- MfaIcodeList];
    TrueVal when (TrueVal =:= true) orelse (TrueVal =:= debug) ->
      finalize_fun_concurrent(MfaIcodeList, Exports, Opts)
  end.

finalize_fun_concurrent(MfaIcodeList, Exports, Opts) ->
  Self = self(),
  case MfaIcodeList of
    [{{M,_,_},_}|_] ->
      CallGraph = hipe_icode_callgraph:construct_callgraph(MfaIcodeList),
      Exported = [{M, F, A} || {F, A} <- Exports],
      Closures = [MFA || {MFA, Icode} <- MfaIcodeList,
			 hipe_icode:icode_is_closure(Icode)],
      %% In principle, a function could both be exported and used as a
      %% closure so make sure to add it only once in Escaping below
      Escaping = ordsets:from_list(Exported ++ Closures),
      NonEscaping = [MFA || {{_M, F, A} = MFA, Icode} <- MfaIcodeList, 
			    not lists:member({F, A}, Exports),
			    not hipe_icode:icode_is_closure(Icode)],
      TypeServerFun =
	fun() ->
	    hipe_icode_coordinator:coordinate(CallGraph, Escaping,
					      NonEscaping, hipe_icode_type)
	end,
      TypeServer = spawn_link(TypeServerFun),
      PPServerFun =
	fun() ->
	    pp_server_start(Opts)
	end,
      PPServer = spawn_link(PPServerFun),
      RangeServerFun =
	fun() ->
	    hipe_icode_coordinator:coordinate(CallGraph, Escaping,
					      NonEscaping, hipe_icode_range)
	end,
      RangeServer = spawn_link(RangeServerFun),
      Servers = #comp_servers{pp_server = PPServer,
			      range = RangeServer,
			      type = TypeServer},
      CompFuns =
	[fun() ->
	     set_architecture(Opts),
	     pre_init(Opts),
	     init(Opts),
	     Self ! finalize_fun_sequential(IcodeFun, Opts, Servers)
	 end || IcodeFun <- MfaIcodeList],
      lists:foreach(fun (F) -> spawn_link(F) end, CompFuns),
      Final = [receive Res when element(1, Res) =:= MFA -> Res end
	       || {MFA, _} <- MfaIcodeList],
      lists:foreach(fun (Pid) -> stop_and_wait(Pid) end,
		    [PPServer, TypeServer, RangeServer]),
      Final;
    [] ->
      []
  end.

stop_and_wait(Pid) ->
  Pid ! {stop, self()},
  receive
    _ -> ok
  end.

finalize_fun_sequential({MFA, Icode}, Opts, Servers) ->
  {T1, _} = erlang:statistics(runtime),
  ?when_option(verbose, Opts, ?debug_msg("Compiling ~w~n", [MFA])),
  try hipe_main:compile_icode(MFA, Icode, Opts, Servers) of
    {native, _Platform, {unprofiled, Code}} ->
      {T2, _} = erlang:statistics(runtime),
      ?when_option(verbose, Opts,
		   ?debug_msg("Compiled ~w in ~.2f s\n", [MFA,(T2-T1)/1000])),
      {MFA, Code};
    {rtl, LinearRtl} ->
      {MFA, LinearRtl};
    {llvm_binary, Binary} ->
      {MFA, Binary}
  catch
    error:Error ->
      ?when_option(verbose, Opts, ?debug_untagged_msg("\n", [])),
      ErrorInfo = {Error, erlang:get_stacktrace()},
      ?error_msg("ERROR: ~p~n", [ErrorInfo]),
      ?EXIT(ErrorInfo)
  end.

pp_server_start(Opts) ->
  set_architecture(Opts),
  garbage_collect(),
  pp_server().

pp_server() ->
  receive
    {print, Fun} ->
      Fun(), pp_server();
    {stop, Pid} ->
      Pid ! {done, self()};
    _ -> 
      pp_server()
  end.

icode_multret(List, Mod, Opts, Exports) ->
  case proplists:get_bool(icode_multret, Opts) of
    true ->
      hipe_icode_mulret:mult_ret(List, Mod, Opts, Exports);
    false ->
      List
  end.

maybe_load(Mod, Bin, WholeModule, Opts) ->
  case proplists:get_bool(load, Opts) of
    false ->
      {module, Mod};
    true ->
      ?when_option(verbose, Opts, ?debug_msg("Loading/linking\n", [])),
      do_load(Mod, Bin, WholeModule)
  end.

do_load(Mod, Bin, BeamBinOrPath) when is_binary(BeamBinOrPath);
				      is_list(BeamBinOrPath) ->
  HostArch = get(hipe_host_arch),
  TargetArch = get(hipe_target_arch),
  %% Make sure we can do the load.
  if HostArch =/= TargetArch ->
    ?EXIT({host_and_target_arch_differ, HostArch, TargetArch});
    true -> ok
  end,
  case code:is_sticky(Mod) of
    true ->
      %% We unpack and repack the Beam binary as a workaround to
      %% ensure that it is not compressed.
      {ok, _, Chunks} = beam_lib:all_chunks(BeamBinOrPath),
      {ok, Beam} = beam_lib:build_module(Chunks),
      %% Don't purge or register sticky mods; just load native.
      code:load_native_sticky(Mod, Bin, Beam);
    false ->
      %% Normal loading of a whole module
      ChunkName = hipe_unified_loader:chunk_name(HostArch),
      {ok, _, Chunks0} = beam_lib:all_chunks(BeamBinOrPath),
      Chunks = [{ChunkName, Bin}|lists:keydelete(ChunkName, 1, Chunks0)],
      {ok, BeamPlusNative} = beam_lib:build_module(Chunks),
      code:load_binary(Mod, code:which(Mod), BeamPlusNative)
  end.

assemble(CompiledCode, Closures, Exports, Options) ->
  case proplists:get_bool(to_llvm, Options) of
    false ->
      case get(hipe_target_arch) of
        ultrasparc ->
          hipe_sparc_assemble:assemble(CompiledCode, Closures, Exports, Options);
        powerpc ->
          hipe_ppc_assemble:assemble(CompiledCode, Closures, Exports, Options);
        ppc64 ->
          hipe_ppc_assemble:assemble(CompiledCode, Closures, Exports, Options);
        arm ->
          hipe_arm_assemble:assemble(CompiledCode, Closures, Exports, Options);
        x86 ->
          hipe_x86_assemble:assemble(CompiledCode, Closures, Exports, Options);
        amd64 ->
          hipe_amd64_assemble:assemble(CompiledCode, Closures, Exports, Options);
        Arch ->
          ?EXIT({executing_on_an_unsupported_architecture, Arch})
      end;
    true ->
      %% Merge already compiled code (per MFA) to a single binary.
      hipe_llvm_merge:finalize(CompiledCode, Closures, Exports)
  end.

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

%% Initialise host and target architectures. Target defaults to host,
%% but can be overridden by passing an option {target, Target}.

set_architecture(Options) ->
  HostArch = erlang:system_info(hipe_architecture),
  put(hipe_host_arch, HostArch),
  put(hipe_target_arch, proplists:get_value(target, Options, HostArch)),
  ok.

%% This sets up some globally accessed stuff that are needed by the
%% compiler process before it even gets the full list of options.
%% Therefore, this expands the current set of options for local use.

pre_init(Opts) ->
  Options = expand_options(Opts, get(hipe_target_arch)),
  %% Initialise some counters used for measurements and benchmarking. If
  %% the option 'measure_regalloc' is given the compilation will return
  %% a keylist with the counter values.
  put(hipe_time,
      case proplists:get_value(time, Options, false) of
	true -> [hipe, hipe_main];
	OptTime -> OptTime
      end),
  lists:foreach(fun (T) -> ?set_hipe_timer_val(T, 0) end, hipe_timers()),
  lists:foreach(fun (Counter) ->
		    case Counter of
		      {CounterName, InitVal} -> put(CounterName, InitVal);
		      CounterName -> put(CounterName, 0)
		    end
		end,
		proplists:get_value(counters, Options, [])),
  put(hipe_debug,     proplists:get_bool(debug, Options)),
  put(hipe_inline_fp, proplists:get_bool(inline_fp, Options)),
  ok.

%% Prepare the compiler process by setting up variables which are
%% accessed globally. Options have been fully expanded at ths point.

init(_Options) ->
  put(callersavetime, 0),
  put(totalspill, {0,0}),
  put(spilledtemps, 0),
  put(pre_ra_instrs, 0),
  put(post_ra_instrs, 0),
  put(pre_ra_temps, 0),
  put(post_ra_temps, 0),
  put(noregs, 0),
  put(bbs, 0),
  ok.

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

post(Res, Icode, Options) ->
  TimerVals = 
    case proplists:get_value(timers, Options) of
      Timers when is_list(Timers) ->
	[{Timer, ?get_hipe_timer_val(Timer)} || Timer <- Timers];
      _ -> []
    end,
  CounterVals = 
    case proplists:get_value(counters, Options) of
      Counters when is_list(Counters) ->
	[case Counter of
	   {CounterName, _InitVal} -> {CounterName, get(CounterName)};
	   CounterName -> {CounterName, get(CounterName)}
	 end
	 || Counter <- Counters];
      _ -> []
    end,
  Measures = 
    case proplists:get_bool(measure_regalloc, Options) of
      true ->
	get();  % return whole process dictionary list (simplest way...)
      false -> []
    end,
  Info = TimerVals ++ CounterVals ++ Measures,
  case proplists:get_bool(get_called_modules, Options) of
    true ->
      CalledMods = hipe_icode_callgraph:get_called_modules(Icode),
      case Info of
	[] ->
	  {Res, {called_modules, CalledMods}};
	_ ->
	  {Res, {info, Info}, {called_modules, CalledMods}}
      end;
    false ->
      case Info of
	[] ->
	  Res;
	_ ->
	  {Res, {info, Info}}
      end
  end.

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

%% @doc Returns the current HiPE version as a string().
-spec version() -> nonempty_string().

version() ->
  ?VERSION_STRING().

%% @doc Returns checksum identifying the target runtime system.
-spec erts_checksum() -> integer().

erts_checksum() ->
  ?HIPE_ERTS_CHECKSUM.

%% --------------------------------------------------------------------
%% D O C U M E N T A T I O N   -   H E L P 
%% --------------------------------------------------------------------

%% @doc Prints on-line documentation to the standard output.
-spec help() -> 'ok'.

help() ->
  M =
    "The HiPE Compiler (Version " ++ ?VERSION_STRING() ++ ")\n" ++
    "\n" ++
    " The normal way to native-compile Erlang code using HiPE is to\n" ++
    " include `native' in the Erlang compiler options, as in:\n" ++
    "     1> c(my_module, [native]).\n" ++
    " Options to the HiPE compiler must then be passed as follows:\n" ++
    "     1> c(my_module, [native,{hipe,Options}]).\n" ++
    " Use `help_options()' for details.\n" ++
    "\n" ++
    " Utility functions:\n" ++
    "   help()\n" ++
    "     Prints this message.\n" ++
    "   help_options()\n" ++
    "     Prints a description of options recognized by the\n" ++
    "     HiPE compiler.\n" ++
    "   help_option(Option)\n" ++
    "     Prints a description of that option.\n" ++
    "   help_debug_options()\n" ++
    "     Prints a description of debug options.\n" ++
    "   version() ->\n" ++
    "     Returns the HiPE version as a string'.\n" ++
    "   erts_checksum() ->\n" ++
    "     Returns a checksum identifying the target runtime system.\n" ++
    "\n" ++
    " For HiPE developers only:\n" ++
    "  Use `help_hiper()' for information about HiPE's low-level interface\n",
  io:put_chars(M),
  ok.

-spec help_hiper() -> 'ok'.

help_hiper() ->
  M =
    " This interface is supposed to be used by HiPE-developers only!\n" ++
    " Note that all options are specific to the HiPE compiler.\n" ++
    "   c(Name,Options)\n" ++ 
    "     Compiles the module or function Name and loads it\n" ++
    "     to memory. Name is an atom or a tuple {M,F,A}.\n" ++
    "   c(Name)\n" ++
    "     As above, but using only default options.\n" ++
    "   f(File,Options)\n" ++ 
    "     As c(Name,File,Options), but taking the module name\n" ++
    "     from File.\n" ++
    "   f(File)\n" ++ 
    "     As above, but using only default options.\n" ++
    "   compile(Name,Options)\n" ++
    "     Compiles the module or function Name to a binary.\n" ++
    "     By default, this does not load to memory.\n" ++
    "   compile(Name)\n" ++ 
    "     As above, but using only default options.\n" ++
    "   file(File,Options)\n" ++ 
    "     As compile(Name,File,Options), but taking the\n" ++
    "     module name from File.\n" ++
    "   file(File)\n" ++ 
    "     As above, but using only default options.\n" ++
    "   load(Module)\n" ++
    "     Loads the named module into memory.\n",
  io:put_chars(M),
  ok.

%% TODO: it should be possible to specify the target somehow when asking
%% for available options. Right now, you only see host machine options.

%% @doc Prints documentation about options to the standard output.
-spec help_options() -> 'ok'.

help_options() ->
  HostArch = erlang:system_info(hipe_architecture),
  O1 = expand_options([o1], HostArch),
  O2 = expand_options([o2], HostArch),
  O3 = expand_options([o3], HostArch),
  io:format("HiPE Compiler Options\n" ++
	    " Boolean-valued options generally have corresponding " ++
	    "aliases `no_...',\n" ++
	    " and can also be specified as `{Option, true}' " ++
	    "or `{Option, false}.\n\n" ++
	    " General boolean options:\n" ++
	    "   ~p.\n\n" ++
	    " Non-boolean options:\n" ++
	    "   o#, where 0 =< # =< 3:\n" ++
	    "     Select optimization level (the default is 2).\n\n" ++
	    " Further options can be found below; " ++
	    "use `hipe:help_option(Name)' for details.\n\n" ++
	    " Aliases:\n" ++
	    "   pp_all = ~p,\n" ++
	    "   pp_sparc = pp_native,\n" ++
	    "   pp_x86 = pp_native,\n" ++
	    "   pp_amd64 = pp_native,\n" ++
	    "   pp_ppc = pp_native,\n" ++
	    "   o0,\n" ++
	    "   o1 = ~p,\n" ++
	    "   o2 = ~p ++ o1,\n" ++
	    "   o3 = ~p ++ o2.\n",
	    [ordsets:from_list([verbose, debug, time, load, pp_beam,
				pp_icode, pp_rtl, pp_native, pp_asm,
				timeout]),
	     expand_options([pp_all], HostArch),
	     O1 -- [o1],
	     (O2 -- O1) -- [o2],
	     (O3 -- O2) -- [o3]]),
  ok.

%% Documentation of the individual options.
%% If you add an option, please add help-text here.

-spec option_text(atom()) -> string().

option_text('O') ->
  "Specify optimization level. Used as o1, o2, o3.\n" ++
  "    At the moment levels 0 - 3 are implemented.\n" ++
  "    Aliases: 'O1', 'O2', O3'.";
option_text(caller_save_spill_restore) ->
  "Activates caller save register spills and restores";
option_text(debug) ->
  "Outputs internal debugging information during compilation";
option_text(icode_call_elim) ->
  "Performs call elimination of BIFs that are side-effect free\n" ++
  "only on some argument types";
option_text(icode_range) ->
  "Performs integer range analysis on the Icode level";
option_text(icode_ssa_check) ->
  "Checks whether Icode is on SSA form or not";
option_text(icode_ssa_copy_prop) ->
  "Performs copy propagation on Icode SSA";
option_text(icode_ssa_const_prop) ->
  "Performs sparse conditional constant propagation on Icode SSA";
option_text(icode_ssa_struct_reuse) ->
  "Factors out common tuple and list constructions on Icode SSA";
option_text(icode_type) ->
  "Performs type analysis on the Icode level\n" ++
  "and then simplifies the code based on the results of this analysis";
option_text(load) ->
  "Automatically load the produced native code into memory";
option_text(peephole) ->
  "Enables peephole optimizations";
option_text(pmatch) ->
  "Enables pattern matching compilation when compiling from Core;\n" ++
  "has no effect when compiling from BEAM bytecode";
option_text(pp_asm) ->
  "Displays assembly listing with addresses and bytecode\n" ++
  "Currently available for x86 only";
option_text(pp_beam) ->
  "Display the input BEAM code";
option_text(pp_icode) ->
  "Display the intermediate HiPE-ICode";
option_text(pp_rtl) ->
  "Display the intermediate HiPE-RTL code";
option_text(pp_rtl_lcm) ->
  "Display the intermediate HiPE-RTL lazy code motion sets";
option_text(pp_rtl_ssapre) ->
  "Display the intermediate HiPE-RTL A-SSAPRE sets";
option_text(pp_native) ->
  "Display the generated (back-end specific) native code";
option_text(regalloc) ->
  "Select register allocation algorithm. Used as {regalloc, METHOD}.\n" ++
  "  Currently available methods:\n" ++
  "    naive - spills everything (for debugging and testing)\n" ++
  "    linear_scan - fast; not so good if few registers available\n" ++
  "    graph_color - slow, but gives OK performance\n" ++
  "    coalescing - slower, tries hard to use registers\n" ++
  "    optimistic - another variant of a coalescing allocator";
option_text(remove_comments) ->
  "Strip comments from intermediate code";
option_text(rtl_ssa) ->
  "Perform SSA conversion on the RTL level -- default starting at O2";
option_text(rtl_ssa_const_prop) ->
  "Performs sparse conditional constant propagation on RTL SSA";
option_text(rtl_lcm) ->
  "Perform Lazy Code Motion on RTL";
option_text(rtl_ssapre) ->
  "Perform A-SSAPRE on RTL";
option_text(time) ->
  "Reports the compilation times for the different stages\n" ++
  "of the compiler.\n" ++
  "    {time, Module}       reports timings for the module Module.\n" ++
  "    {time, [M1, M2, M3]} reports timings for the specified modules.\n" ++
  "    {time, all}          reports timings all modules.\n" ++
  "    time                 reports timings for the main module.\n";
option_text(timeout) ->
  "Specify compilation time limit in ms. Used as {timeout, LIMIT}.\n" ++
  "    The limit must be a non-negative integer or the atom 'infinity'.\n" ++
  "    The current default limit is 15 minutes (900000 ms).";
option_text(use_indexing) ->
  "Use indexing for multiple-choice branch selection";
option_text(use_callgraph) ->
  "Compile the functions in a module according to a reversed topological\n" ++
  "sorted order to gain more information when using a persistent lookup\n" ++
  "table for storing intra-modular type information";
option_text(verbose) ->
  "Output information about what is being done";
option_text(Opt) when is_atom(Opt) ->
  "".

%% @doc Prints documentation about a specific option to the standard output.
-spec help_option(comp_option()) -> 'ok'.

help_option(Opt) ->
  HostArch = erlang:system_info(hipe_architecture),
  case expand_options([Opt], HostArch) of
    [Opt] ->
      Name = if is_atom(Opt) -> Opt;
		tuple_size(Opt) =:= 2 -> element(1, Opt)
	     end,
      case option_text(Name) of
	"" ->  
	  case lists:member(Name, opt_keys()) of
	    true ->
	      io:format("~w - Sorry, this option is not documented yet.\n",
			[Name]);
	    _ -> 
	      io:format("Unknown option ~p.\n", [Name])
	  end;
	Txt ->
	  io:fwrite("~w - ~s\n", [Name, Txt])
      end;
    Opts ->
      io:fwrite("This is an alias for: ~p.\n", [Opts])
  end,
  ok.

%% @doc Prints documentation about debugging options to the standard
%% output.
-spec help_debug_options() -> 'ok'.

help_debug_options() ->
  io:format("HiPE compiler debug options:\n" ++
	    "  Might require that some modules have been compiled " ++ 
	    "with the debug flag.\n" ++
	    "    rtl_show_translation - Prints each step in the\n" ++
	    "                           translation from Icode to RTL\n",
	    []),
  ok.

hipe_timers() ->
  [time_ra].

%% ____________________________________________________________________
%% 
%% Option expansion

%% These are currently in use, but not documented:
%%
%%     count_instrs:
%%     icode_type:
%%     icode_range:
%%     {ls_order, Order}:
%%     {regalloc, Algorithm}:
%%     remove_comments
%%     timeregalloc:
%%     timers
%%     use_indexing

%% Valid option keys. (Don't list aliases or negations - the check is
%% done after the options have been expanded to normal form.)

opt_keys() ->
    [
     binary_opt,
     bitlevel_binaries,
     caller_save_spill_restore,
     concurrent_comp,
     core,
     core_transform,
     counters,
     count_instrs,
     count_spills,
     count_temps,
     debug,
     get_called_modules,
     split_arith,
     split_arith_unsafe,
     icode_call_elim,
     icode_inline_bifs,
     icode_ssa_check,
     icode_ssa_copy_prop,
     icode_ssa_const_prop,
     icode_ssa_struct_reuse,
     icode_type,
     icode_range,
     icode_multret,
     inline_fp,
     ls_order,
     load,
     measure_regalloc,
     peephole,
     pmatch,
     pp_asm,
     pp_beam,
     pp_icode,
     pp_icode_ssa,
     pp_icode_split_arith,
     pp_opt_icode,
     pp_range_icode,
     pp_typed_icode,
     pp_icode_liveness,
     pp_native,
     pp_rtl,
     pp_rtl_liveness,
     pp_rtl_ssa,
     pp_rtl_lcm,
     pp_rtl_ssapre,
     pp_rtl_linear,
     regalloc,
     remove_comments,
     rtl_ssa,
     rtl_ssa_const_prop,
     rtl_lcm,
     rtl_ssapre,
     rtl_show_translation,
     spillmin_color,
     target,
     time,
     timeout,
     timeregalloc,
     timers,
     to_rtl,
     to_llvm, % Use the LLVM backend for compilation.
     llvm_save_temps, % Save the LLVM intermediate files in the current
                      % directory; useful for debugging.
     llvm_llc, % Specify llc optimization-level: o1, o2, o3, undefined.
     llvm_opt, % Specify opt optimization-level: o1, o2, o3, undefined.
     use_indexing,
     use_inline_atom_search,
     use_callgraph,
     use_clusters,
     use_jumptable,
     verbose,
     %% verbose_spills,
     x87].

%% Definitions:

o1_opts(TargetArch) ->
  Common = [inline_fp, pmatch, peephole],
  case TargetArch of
    ultrasparc ->
      Common;
    powerpc ->
      Common;
    ppc64 ->
      Common;
    arm ->
      Common -- [inline_fp]; % Pointless optimising for absent hardware
    x86 ->
      [x87 | Common];        % XXX: Temporary until x86 has sse2
    amd64 ->
      Common;
    Arch ->
      ?EXIT({executing_on_an_unsupported_architecture,Arch})
  end.

o2_opts(TargetArch) ->
  Common = [icode_ssa_const_prop, icode_ssa_copy_prop, % icode_ssa_struct_reuse,
	    icode_type, icode_inline_bifs, icode_call_elim, rtl_lcm,
	    rtl_ssa, rtl_ssa_const_prop,
	    spillmin_color, use_indexing, remove_comments,
	    concurrent_comp, binary_opt | o1_opts(TargetArch)],
  case TargetArch of
    T when T =:= amd64 orelse T =:= ppc64 -> % 64-bit targets
      [icode_range | Common];
    _ ->      % T \in [arm, powerpc, ultrasparc, x86]
      Common  % [rtl_ssapre | Common];
    end.

o3_opts(TargetArch) ->
  %% no point checking for target architecture since this is checked in 'o1'
  [icode_range, {regalloc,coalescing} | o2_opts(TargetArch)].

%% Note that in general, the normal form for options should be positive.
%% This is a good programming convention, so that tests in the code say
%% "if 'x' ..." instead of "if not 'no_x' ...".

opt_negations() ->
  [{no_binary_opt, binary_opt},
   {no_bitlevel_binaries, bitlevel_binaries},
   {no_core, core},
   {no_debug, debug},
   {no_get_called_modules, get_called_modules},
   {no_split_arith, split_arith},
   {no_concurrent_comp, concurrent_comp},
   {no_icode_inline_bifs, icode_inline_bifs},
   {no_icode_range, icode_range},
   {no_icode_split_arith, icode_split_arith},
   {no_icode_call_elim, icode_call_elim},
   {no_icode_ssa_check, icode_ssa_check},
   {no_icode_ssa_copy_prop, icode_ssa_copy_prop},
   {no_icode_ssa_const_prop, icode_ssa_const_prop},
   {no_icode_ssa_struct_reuse, icode_ssa_struct_reuse},
   {no_icode_type, icode_type},
   {no_inline_fp, inline_fp},
   {no_load, load},
   {no_peephole, peephole},
   {no_pmatch, pmatch},
   {no_pp_beam, pp_beam},
   {no_pp_icode, pp_icode},
   {no_pp_icode_ssa, pp_icode_ssa},
   {no_pp_opt_icode, pp_opt_icode},
   {no_pp_typed_icode, pp_typed_icode},
   {no_pp_rtl, pp_rtl},
   {no_pp_native, pp_native},
   {no_pp_rtl_lcm, pp_rtl_lcm},
   {no_pp_rtl_ssapre, pp_rtl_ssapre},
   {no_remove_comments, remove_comments},
   {no_rtl_ssa, rtl_ssa},
   {no_rtl_ssa_const_prop, rtl_ssa_const_prop},
   {no_rtl_lcm, rtl_lcm},
   {no_rtl_ssapre, rtl_ssapre},
   {no_rtl_show_translation, rtl_show_translation},
   {no_time, time},
   {no_use_callgraph, use_callgraph},
   {no_use_clusters, use_clusters},
   {no_use_inline_atom_search, use_inline_atom_search},
   {no_use_indexing, use_indexing}].

%% Don't use negative forms in right-hand sides of aliases and expansions!
%% We only expand negations once, before the other expansions are done.

opt_aliases() ->
  [{'O0', o0},
   {'O1', o1},
   {'O2', o2},
   {'O3', o3},
   {pp_sparc, pp_native},
   {pp_x86, pp_native},
   {pp_amd64, pp_native},
   {pp_ppc, pp_native}].

opt_basic_expansions() ->
  [{pp_all, [pp_beam, pp_icode, pp_rtl, pp_native]}].

opt_expansions(TargetArch) ->
  [{o1, o1_opts(TargetArch)},
   {o2, o2_opts(TargetArch)},
   {o3, o3_opts(TargetArch)},
   {to_llvm, llvm_opts(o3)},
   {{to_llvm, o0}, llvm_opts(o0)},
   {{to_llvm, o1}, llvm_opts(o1)},
   {{to_llvm, o2}, llvm_opts(o2)},
   {{to_llvm, o3}, llvm_opts(o3)},
   {x87, [x87, inline_fp]},
   {inline_fp, case TargetArch of  %% XXX: Temporary until x86 has sse2
		 x86 -> [x87, inline_fp];
		 _ -> [inline_fp] end}].

llvm_opts(O) ->
  [to_llvm, {llvm_opt, O}, {llvm_llc, O}].

%% This expands "basic" options, which may be tested early and cannot be
%% in conflict with options found in the source code.

-spec expand_basic_options(comp_options()) -> comp_options().

expand_basic_options(Opts) ->
  proplists:normalize(Opts, [{negations, opt_negations()},
			     {aliases, opt_aliases()},
			     {expand, opt_basic_expansions()}]).

-spec expand_kt2(comp_options()) -> comp_options().

expand_kt2(Opts) -> 
  proplists:normalize(Opts, [{expand, [{kt2_type,
					[{use_callgraph, fixpoint}, core, 
					 {core_transform, cerl_typean}]}]}]).

%% Note that the given
%% list should contain the total set of options, since things like 'o2'
%% are expanded here. Basic expansions are processed here also, since
%% this function is called from the help functions.

-spec expand_options(comp_options(), hipe_architecture()) -> comp_options().

expand_options(Opts, TargetArch) ->
  proplists:normalize(Opts, [{negations, opt_negations()},
			     {aliases, opt_aliases()},
			     {expand, opt_basic_expansions()},
			     {expand, opt_expansions(TargetArch)}]).

-spec check_options(comp_options()) -> 'ok'.

check_options(Opts) ->
  Keys = ordsets:from_list(opt_keys()),
  Used = ordsets:from_list(proplists:get_keys(Opts)),
  case ordsets:subtract(Used, Keys) of
    [] ->
      ok;
    L ->
      ?WARNING_MSG("Unknown options: ~p.\n", [L]),
      ok
  end.

-spec llvm_support_available() -> boolean().

llvm_support_available() ->
  get_llvm_version() >= 3.4.

get_llvm_version() ->
  OptStr = os:cmd("opt -version"),
  SubStr = "LLVM version ", N = length(SubStr),
  case string:str(OptStr, SubStr) of
     0 -> % No opt available
       0.0;
     S ->
       case string:to_float(string:sub_string(OptStr, S + N)) of
         {error, _} -> 0.0; %XXX: Assumes no revision numbers in versioning
         {Float, _} -> Float
       end
  end.

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