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%%
%% %CopyrightBegin%
%%
%% Copyright Ericsson AB 2001-2012. 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%
%%
-module(fprof_SUITE).

-include_lib("common_test/include/ct.hrl").

%% Test server framework exports
-export([all/0, suite/0, not_run/1]).

%% Test suites
-export([stack_seq/1, tail_seq/1, create_file_slow/1, spawn_simple/1,
         imm_tail_seq/1, imm_create_file_slow/1, imm_compile/1,
         cpu_create_file_slow/1]).

%% Other exports
-export([create_file_slow/2]).

%% Debug exports
-export([parse/1, verify/2]).
-export([spawn_simple_test/3]).

%-define(debug,true).
-ifdef(debug).
-define(dbg(Str,Args), io:format(Str,Args)).
-else.
-define(dbg(Str,Args), ok).
-endif.


%%%---------------------------------------------------------------------
%%% Test suites
%%%---------------------------------------------------------------------


suite() ->
    [{ct_hooks,[ts_install_cth]},
     {timetrap,{seconds,60}}].

all() -> 
    case test_server:is_native(fprof_SUITE) of
        true -> [not_run];
        false ->
            [stack_seq, tail_seq, create_file_slow, spawn_simple,
             imm_tail_seq, imm_create_file_slow, imm_compile,
             cpu_create_file_slow]
    end.


not_run(Config) when is_list(Config) ->
    {skipped, "Native code"}.

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

stack_seq(doc) ->
    ["Tests a stack recursive variant of lists:seq/3"];
stack_seq(suite) ->
    [];
stack_seq(Config) when is_list(Config) ->
    PrivDir = proplists:get_value(priv_dir, Config),
    TraceFile = filename:join(PrivDir,
                              ?MODULE_STRING"_stack_seq.trace"),
    AnalysisFile = filename:join(PrivDir,
                                 ?MODULE_STRING"_stack_seq.analysis"),
    Start = 1,
    Stop = 1000,
    Succ = fun (X) -> X + 1 end,
    ok = fprof:stop(kill),
    %%
    TS0 = erlang:monotonic_time(),
    R0 = fprof:apply(fun seq/3, [Start, Stop, Succ], [{file, TraceFile}]),
    TS1 = erlang:monotonic_time(),
    R = seq(Start, Stop, Succ),
    TS2 = erlang:monotonic_time(),
    ok = fprof:profile(file, TraceFile),
    ok = fprof:analyse(),
    ok = fprof:analyse(dest, AnalysisFile),
    ok = fprof:stop(),
    R = R0,
    %%
    {ok, [T, P]} = parse(AnalysisFile),
    io:format("~p~n~n~p~n", [P, ets:tab2list(T)]),
    ok = (catch verify(T, P)),
    Proc = pid_to_list(self()),
    case P of
        [{analysis_options, _},
         [{totals, _, Acc, _}],
         [{Proc, _, undefined, _} | _]] ->
            ok
    end,
    %%
    check_own_and_acc(TraceFile,AnalysisFile),
    %%
    ets:delete(T),
    file:delete(TraceFile),
    file:delete(AnalysisFile),
    Acc1 = TS1 - TS0,
    Acc2 = TS2 - TS1,
    io:format("ts:~w, fprof:~w, bare:~w.~n", [Acc, Acc1, Acc2]),
    {comment, io_lib:format("~p times slower", [Acc1/Acc2])}.

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

tail_seq(doc) ->
    ["Tests a tail recursive variant of lists:seq/3"];
tail_seq(suite) ->
    [];
tail_seq(Config) when is_list(Config) ->
    PrivDir = proplists:get_value(priv_dir, Config),
    TraceFile = filename:join(PrivDir,
                              ?MODULE_STRING"_tail_seq.trace"),
    AnalysisFile = filename:join(PrivDir,
                                 ?MODULE_STRING"_tail_seq.analysis"),
    Start = 1,
    Stop = 1000,
    Succ = fun (X) -> X + 1 end,
    ok = fprof:stop(kill),
    %%
    TS0 = erlang:monotonic_time(),
    R = seq_r(Start, Stop, Succ),
    TS1 = erlang:monotonic_time(),
    %%
    R1 = fprof:apply(fun seq_r/3, [Start, Stop, Succ],
                     [{file, TraceFile}]),
    TS2 = erlang:monotonic_time(),
    ok = fprof:profile([{file,TraceFile}]),
    ok = fprof:analyse(),
    ok = fprof:analyse(dest, AnalysisFile),
    ok = fprof:stop(),
    R = R1,
    %%
    {ok, [T, P]} = parse(AnalysisFile),
    io:format("~p~n~n~p~n", [P, ets:tab2list(T)]),
    ok = verify(T, P),
    Proc = pid_to_list(self()),
    case P of
        [{analysis_options, _},
         [{totals, _, Acc, _}],
         [{Proc, _, undefined, _} | _]] ->
            ok
    end,
    %%
    check_own_and_acc(TraceFile,AnalysisFile),
    %%
    ets:delete(T),
    file:delete(TraceFile),
    file:delete(AnalysisFile),
    Acc1 = TS1 - TS0,
    Acc2 = TS2 - TS1,
    io:format("ts:~w, fprof:~w, bare:~w.~n", [Acc, Acc2, Acc1]),
    {comment, io_lib:format("~p times slower", [Acc2/Acc1])}.

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

%% Tests the create_file_slow benchmark.
create_file_slow(Config) ->
    case test_server:is_native(lists) orelse
         test_server:is_native(file) of
        true ->
            {skip,"Native libs -- tracing does not work"};
        false ->
            do_create_file_slow(Config)
    end.

do_create_file_slow(Config) ->
    PrivDir = proplists:get_value(priv_dir, Config),
    TraceFile = filename:join(PrivDir,
                              ?MODULE_STRING"_create_file_slow.trace"),
    AnalysisFile = filename:join(PrivDir,
                                 ?MODULE_STRING"_create_file_slow.analysis"),
    DataFile = filename:join(PrivDir,
                             ?MODULE_STRING"_create_file_slow.data"),
    ok = fprof:stop(kill),
    %%
    TS0 = erlang:monotonic_time(),
    ok = create_file_slow(DataFile, 1024),
    TS1 = erlang:monotonic_time(),
    %%
    ok = file:delete(DataFile),
    TS2 = erlang:monotonic_time(),
    ok = fprof:apply(?MODULE, create_file_slow, [DataFile, 1024],
                     [{file, TraceFile}]),
    TS3 = erlang:monotonic_time(),
    ok = fprof:profile(file, TraceFile),
    ok = fprof:analyse(),
    ok = fprof:analyse(dest, AnalysisFile),
    ok = fprof:stop(),
    %%
    {ok, [T, P]} = parse(AnalysisFile),
    io:format("~p~n~n~p~n", [P, ets:tab2list(T)]),
    ok = verify(T, P),
    Proc = pid_to_list(self()),
    case P of
        [{analysis_options, _},
         [{totals, _, Acc, _}],
         [{Proc, _, undefined, _} | _]] ->
            ok
    end,
    %%
    check_own_and_acc(TraceFile,AnalysisFile),
    %%
    ets:delete(T),
    file:delete(DataFile),
    file:delete(TraceFile),
    file:delete(AnalysisFile),
    Acc1 = TS1 - TS0,
    Acc3 = TS3 - TS2,
    io:format("ts:~w, fprof:~w, bare:~w.~n", [Acc, Acc3, Acc1]),
    {comment, io_lib:format("~p times slower", [Acc3/Acc1])}.



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

spawn_simple(doc) ->
    ["Tests process spawn"];
spawn_simple(suite) ->
    [];
spawn_simple(Config) when is_list(Config) ->
    PrivDir = proplists:get_value(priv_dir, Config),
    TraceFile = filename:join(PrivDir,
                              ?MODULE_STRING"_spawn_simple.trace"),
    AnalysisFile = filename:join(PrivDir,
                                 ?MODULE_STRING"_spawn_simple.analysis"),
    Start = 1,
    Stop = 1000,
    Succ = fun (X) -> X + 1 end,
    ok = fprof:stop(kill),
    %%
    TS0 = erlang:monotonic_time(),
    {{_, R1}, {_, R2}} = spawn_simple_test(Start, Stop, Succ),
    TS1 = erlang:monotonic_time(),
    %%
    ok = fprof:trace(start, TraceFile),
    {{P1, R3}, {P2, R4}} = spawn_simple_test(Start, Stop, Succ),
    ok = fprof:trace(stop),
    TS2 = erlang:monotonic_time(),
    ok = fprof:profile(file, TraceFile),
    ok = fprof:analyse(),
    ok = fprof:analyse(dest, AnalysisFile),
    ok = fprof:stop(),
    R1 = R3,
    R2 = R4,
    %%
    {ok, [T, P]} = parse(AnalysisFile),
    io:format("~p~n~n~p~n", [P, ets:tab2list(T)]),
    ok = verify(T, P),
    Proc1 = pid_to_list(P1),
    Proc2 = pid_to_list(P2),
    Proc0 = pid_to_list(self()),
    io:format("~p~n ~p ~p ~p~n", [P, Proc0, Proc1, Proc2]),
    [{analysis_options, _}, [{totals, _, Acc, _}] | Procs] = P,
    [[{Proc0, _, undefined, _} | _]] = lists:filter(
                                         fun ([Pt | _]) when element(1, Pt) == Proc0 -> true;
                                             (_) -> false
                                         end, Procs),
    [[{Proc1, _, undefined, _},
      {spawned_by, Proc0},
      {spawned_as, {erlang, apply, ["#Fun"++_, []]}},
      {initial_calls, [{erlang, apply, 2},
                       {?MODULE, '-spawn_simple_test/3-fun-0-', 4}]}
      | _]] = lists:filter(fun ([Pt | _]) when element(1, Pt) == Proc1 -> true;
                               (_) -> false
                           end, Procs),
    [[{Proc2, _, undefined, _},
      {spawned_by, Proc0},
      {spawned_as, {erlang, apply, ["#Fun"++_, []]}},
      {initial_calls, [{erlang, apply, 2},
                       {?MODULE, '-spawn_simple_test/3-fun-1-', 4}]}
      | _]] = lists:filter(fun ([Pt | _]) when element(1, Pt) == Proc2 -> true;
                               (_) -> false
                           end, Procs),
    3 = length(Procs),
    R1 = lists:reverse(R2),
    %%
    check_own_and_acc(TraceFile,AnalysisFile),
    %%
    ets:delete(T),
    file:delete(TraceFile),
    file:delete(AnalysisFile),
    Acc1 = TS1 - TS0,
    Acc2 = TS2 - TS1,
    io:format("ts:~w, fprof:~w, bare:~w.~n", [Acc, Acc2, Acc1]),
    {comment, io_lib:format("~p times slower", [Acc2/Acc1])}.


spawn_simple_test(Start, Stop, Succ) ->
    Parent = self(),
    Seq = spawn_link(fun() ->
                             Parent ! {self(), seq(Start, Stop, Succ)}
                     end),

    SeqR = spawn_link(fun() ->
                              Parent ! {self(), seq_r(Start, Stop, Succ)}
                      end),
    receive
        {Seq, SeqResult} ->
            receive
                {SeqR, SeqRResult} ->
                    {{Seq, SeqResult}, {SeqR, SeqRResult}}
            end
    end.



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

imm_tail_seq(doc) ->
    ["Tests a tail recursive variant of lists:seq/3 ",
     "with immediate trace to profile"];
imm_tail_seq(suite) ->
    [];
imm_tail_seq(Config) when is_list(Config) ->
    PrivDir = proplists:get_value(priv_dir, Config),
    AnalysisFile = filename:join(PrivDir,
                                 ?MODULE_STRING"_imm_tail_seq.analysis"),
    Start = 1,
    Stop = 1000,
    Succ = fun (X) -> X + 1 end,
    ok = fprof:stop(kill),
    catch eprof:stop(),
    %%
    TS0 = erlang:monotonic_time(),
    R0 = seq_r(Start, Stop, Succ),
    TS1 = erlang:monotonic_time(),
    %%
    profiling = eprof:start_profiling([self()]),
    TS2 = erlang:monotonic_time(),
    R2 = seq_r(Start, Stop, Succ),
    TS3 = erlang:monotonic_time(),
    profiling_stopped = eprof:stop_profiling(),
    R2 = R0,
    %%
    eprof:analyze(),
    stopped = eprof:stop(),
    %%
    {ok, Tracer} = fprof:profile(start),
    ok = fprof:trace([start, {tracer, Tracer}]),
    TS4 = erlang:monotonic_time(),
    R4 = seq_r(Start, Stop, Succ),
    TS5 = erlang:monotonic_time(),
    ok = fprof:trace(stop),
    ok = fprof:analyse(),
    ok = fprof:analyse(dest, AnalysisFile),
    ok = fprof:stop(),
    R4 = R0,
    %%
    {ok, [T, P]} = parse(AnalysisFile),
    io:format("~p~n~n~p~n", [P, ets:tab2list(T)]),
    ok = verify(T, P),
    Proc = pid_to_list(self()),
    case P of
        [{analysis_options, _},
         [{totals, _, Acc, _}],
         [{Proc, _, undefined, _} | _]] -> ok
    end,
    %%
    ets:delete(T),
    file:delete(AnalysisFile),
    Acc1 = TS1 - TS0,
    Acc3 = TS3 - TS2,
    Acc5 = TS5 - TS4,
    io:format("~p (plain), ~p (eprof), ~p (fprof), ~p (cpu)~n",
              [Acc1/1000, Acc3/1000, Acc5/1000, Acc/1000]),
    {comment, io_lib:format("~p/~p (fprof/eprof) times slower", 
                            [Acc5/Acc1, Acc3/Acc1])}.

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

imm_create_file_slow(doc) ->
    ["Tests a tail recursive variant of lists:seq/3 ",
     "with immediate trace to profile"];
imm_create_file_slow(suite) ->
    [];
imm_create_file_slow(Config) when is_list(Config) ->
    PrivDir = proplists:get_value(priv_dir, Config),
    DataFile = filename:join(PrivDir,
                             ?MODULE_STRING"_imm_create_file_slow.data"),
    AnalysisFile = filename:join(PrivDir,
                                 ?MODULE_STRING"_imm_create_file_slow.analysis"),
    ok = fprof:stop(kill),
    %%
    TS0 = erlang:monotonic_time(),
    ok = create_file_slow(DataFile, 1024),
    TS1 = erlang:monotonic_time(),
    ok = file:delete(DataFile),
    %%
    {ok, Tracer} = fprof:profile(start),
    TS2 = erlang:monotonic_time(),
    ok = fprof:apply(?MODULE, create_file_slow, [DataFile, 1024],
                     [{tracer, Tracer}, continue]),
    TS3 = erlang:monotonic_time(),
    ok = fprof:profile(stop),
    ok = fprof:analyse(),
    ok = fprof:analyse(dest, AnalysisFile),
    ok = fprof:stop(),
    %%
    {ok, [T, P]} = parse(AnalysisFile),
    io:format("~p~n~n~p~n", [P, ets:tab2list(T)]),
    ok = verify(T, P),
    Proc = pid_to_list(self()),
    case P of
        [{analysis_options, _},
         [{totals, _, Acc, _}],
         [{Proc, _, undefined, _} | _]] ->
            ok
    end,
    %%
    ets:delete(T),
    file:delete(DataFile),
    file:delete(AnalysisFile),
    Acc1 = TS1 - TS0,
    Acc3 = TS3 - TS2,
    io:format("ts:~w, fprof:~w, bare:~w.~n", [Acc, Acc3, Acc1]),
    {comment, io_lib:format("~p times slower", [Acc3/Acc1])}.

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

imm_compile(doc) ->
    ["Tests to compile a small source file ",
     "with immediate trace to profile"];
imm_compile(suite) ->
    [];
imm_compile(Config) when is_list(Config) ->
    ct:timetrap({minutes, 20}),
    DataDir = proplists:get_value(data_dir, Config),
    SourceFile = filename:join(DataDir, "foo.erl"),
    PrivDir = proplists:get_value(priv_dir, Config),
    AnalysisFile = filename:join(PrivDir,
                                 ?MODULE_STRING"_imm_compile.analysis"),
    ok = fprof:stop(kill),
    catch eprof:stop(),
    %%
    {ok, foo, _} = compile:file(SourceFile, [binary]),
    TS0 = erlang:monotonic_time(),
    {ok, foo, _} = compile:file(SourceFile, [binary]),
    TS1 = erlang:monotonic_time(),
    %%
    profiling = eprof:start_profiling([self()]),
    TS2 = erlang:monotonic_time(),
    {ok, foo, _} = compile:file(SourceFile, [binary]),
    TS3 = erlang:monotonic_time(),
    profiling_stopped = eprof:stop_profiling(),
    %%
    eprof:analyze(),
    stopped = eprof:stop(),
    %%
    {ok, Tracer} = fprof:profile(start),
    ok = fprof:trace([start, {tracer, Tracer}]),
    TS4 = erlang:monotonic_time(),
    {ok, foo, _} = compile:file(SourceFile, [binary]),
    TS5 = erlang:monotonic_time(),
    ok = fprof:trace(stop),
    %%
    io:format("Analysing...~n"),
    ok = fprof:analyse(dest, AnalysisFile),
    ok = fprof:stop(),
    %%
    {ok, [T, P]} = parse(AnalysisFile),
    io:format("~p~n", [P]),
    Acc1 = TS1 - TS0,
    Acc3 = TS3 - TS2,
    Acc5 = TS5 - TS4,
    io:format("Verifying...~n"),
    ok = verify(T, P),
    case P of
        [{analysis_options, _},
         [{totals, _, Acc, _}] | _] ->
            ok
    end,
    %%
    ets:delete(T),
    file:delete(AnalysisFile),
    io:format("~p (plain), ~p (eprof), ~p (fprof), ~p(cpu)~n",
              [Acc1/1000, Acc3/1000, Acc5/1000, Acc/1000]),
    {comment, io_lib:format("~p/~p (fprof/eprof) times slower", 
                            [Acc5/Acc1, Acc3/Acc1])}.

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

cpu_create_file_slow(doc) ->
    ["Tests the create_file_slow benchmark using cpu_time"];
cpu_create_file_slow(suite) ->
    [];
cpu_create_file_slow(Config) when is_list(Config) ->
    PrivDir = proplists:get_value(priv_dir, Config),
    TraceFile =
    filename:join(PrivDir, ?MODULE_STRING"_cpu_create_file_slow.trace"),
    AnalysisFile =
    filename:join(PrivDir, ?MODULE_STRING"_cpu_create_file_slow.analysis"),
    DataFile =
    filename:join(PrivDir, ?MODULE_STRING"_cpu_create_file_slow.data"),
    ok = fprof:stop(kill),
    %%
    TS0 = erlang:monotonic_time(),
    Result = (catch fprof:apply(?MODULE, create_file_slow,
                                [DataFile, 1024],
                                [{file, TraceFile}, cpu_time])),
    TS1 = erlang:monotonic_time(),
    TestResult =
    case Result of
        ok ->
            ok = fprof:profile(file, TraceFile),
            ok = fprof:analyse(),
            ok = fprof:analyse(dest, AnalysisFile),
            ok = fprof:stop(),
            %%
            {ok, [T, P]} = parse(AnalysisFile),
            io:format("~p~n~n~p~n", [P, ets:tab2list(T)]),
            ok = verify(T, P),
            Proc = pid_to_list(self()),
            case P of
                [{analysis_options, _},
                 [{totals, _, Acc, _}],
                 [{Proc, _, undefined, _} | _]] ->
                    ok
            end,
            %%
            check_own_and_acc(TraceFile,AnalysisFile),
            %%
            ets:delete(T),
            file:delete(DataFile),
            file:delete(TraceFile),
            file:delete(AnalysisFile),
            Acc1 = TS1 - TS0,
            io:format("cpu_ts:~w, fprof:~w~n", [Acc, Acc1]),
            {comment, io_lib:format("~p% cpu utilization",
                                    [100*Acc/Acc1])};
        {'EXIT', not_supported} ->
            case {os:type(), os:version()} of
                {{unix, sunos}, {Major, Minor, _}}
                  when Major >= 5, Minor >= 7 ->
                    ct:fail(Result);
                _ ->
                    {skipped, "not_supported"}
            end;
        _ ->
            ct:fail(Result)
    end,
    TestResult.


%%%---------------------------------------------------------------------
%%% Functions to test
%%%---------------------------------------------------------------------



%% Stack recursive seq
seq(Stop, Stop, Succ) when is_function(Succ) ->
    [Stop];
seq(Start, Stop, Succ) when is_function(Succ) ->
    [Start | seq(Succ(Start), Stop, Succ)].



%% Tail recursive seq, result list is reversed
seq_r(Start, Stop, Succ) when is_function(Succ) ->
    seq_r(Start, Stop, Succ, []).

seq_r(Stop, Stop, _, R) ->
    [Stop | R];
seq_r(Start, Stop, Succ, R) ->
    seq_r(Succ(Start), Stop, Succ, [Start | R]).



create_file_slow(Name, N) when is_integer(N), N >= 0 ->
    {ok, FD} = 
    file:open(Name, [raw, write, delayed_write, binary]),
    if N > 256 ->
           ok = file:write(FD,
                           lists:map(fun (X) -> <<X:32/unsigned>> end,
                                     lists:seq(0, 255))),
           ok = create_file_slow(FD, 256, N);
       true ->
           ok = create_file_slow(FD, 0, N)
    end,
    ok = file:close(FD).

create_file_slow(_FD, M, M) ->
    ok;
create_file_slow(FD, M, N) ->
    ok = file:write(FD, <<M:32/unsigned>>),
    create_file_slow(FD, M+1, N).



%%%---------------------------------------------------------------------
%%% Profile verification functions
%%%---------------------------------------------------------------------


verify(Tab, [{analysis_options, _},
             [{totals, Cnt, Acc, Own} | _] | Processes]) ->
    Processes_1 = 
    lists:map(
      fun ([{Proc, Cnt_P, undefined, Own_P} | _]) ->
              case sum_process(Tab, Proc) of
                  {Proc, Cnt_P, Acc_P, Own_P} = Clocks
                    when Acc_P >= Own_P ->
                      Clocks;
                  Weird ->
                      throw({error, [?MODULE, ?LINE, Weird]})
              end
      end,
      Processes),
    case lists:foldl(
           fun ({_, Cnt_P2, Acc_P2, Own_P2},
                {totals, Cnt_T, Acc_T, Own_T}) ->
                   {totals, Cnt_P2+Cnt_T, Acc_P2+Acc_T, Own_P2+Own_T}
           end,
           {totals, 0, 0, 0},
           Processes_1) of
        {totals, Cnt, Acc_T, Own} when Acc_T >= Acc ->
            ok;
        Weird ->
            throw({error, [?MODULE, ?LINE, Weird]})
    end.


sum_process(Tab, Proc) ->
    ets_select_fold(
      Tab, [{{{Proc, '_'}, '_'}, [], ['$_']}], 100,
      fun ({{P, MFA}, {Callers, {MFA, Cnt, Acc, Own}, Called}},
           {P, Cnt_P, Acc_P, Own_P}) when P == Proc ->
              ok = verify_callers(Tab, Proc, MFA, Callers),
              ok = verify_called(Tab, Proc, MFA, Called),
              {P, Cnt+Cnt_P, Acc+Acc_P, Own+Own_P};
          (Weird, Clocks) ->
              throw({error, [?MODULE, ?LINE, Weird, Clocks]})
      end,
      {Proc, 0, 0, 0}).

verify_callers(_, _, _, []) ->
    ok;
verify_callers(Tab, Proc, MFA, [{Caller, Cnt, Acc, Own} | Tail]) ->
    Id = {Proc, Caller},
    case ets:lookup(Tab, Id) of
        [{Id, {_, {Caller, _, _, _}, Called}}] ->
            case lists:keysearch(MFA, 1, Called) of
                {value, {MFA, Cnt, Acc, Own}} ->
                    verify_callers(Tab, Proc, MFA, Tail);
                false ->
                    throw({error, [?MODULE, ?LINE, MFA, Id]})
            end;
        Weird ->
            throw({error, [?MODULE, ?LINE, Weird]})
    end.

verify_called(_, _, _, []) ->
    ok;
verify_called(Tab, Proc, MFA, [{Called, Cnt, Acc, Own} | Tail]) ->
    Id = {Proc, Called},
    case ets:lookup(Tab, Id) of
        [{Id, {Callers, {Called, _, _, _}, _}}] ->
            case lists:keysearch(MFA, 1, Callers) of
                {value, {MFA, Cnt, Acc, Own}} ->
                    verify_called(Tab, Proc, MFA, Tail);
                false ->
                    throw({error, [?MODULE, ?LINE, MFA, Id]})
            end;
        Weird ->
            throw({error, [?MODULE, ?LINE, Weird]})
    end.



%% Parse a analysis file and return an Ets table with all function entries, 
%% and a list of process entries. Checks the concistency of the function
%% entries when they are read.
parse(Filename) ->
    case file:open(Filename, [read]) of
        {ok, FD} ->
            Result = parse_stream(FD),
            file:close(FD),
            Result;
        Error ->
            Error
    end.

parse_stream(FD) ->
    Tab = ets:new(fprof_SUITE, []),
    parse_stream(FD, Tab, [], void).

parse_stream(FD, Tab, R, Proc) ->
    case catch io:read(FD, '') of
        {'EXIT', _} ->
            {error, [?MODULE, ?LINE]};
        {ok, Term} ->
            case parse_term(Term) of
                {ok, {analysis_options, _} = Term_1}
                  when Proc == void ->
                    parse_stream(FD, Tab, [Term_1 | R], analysis_options);
                {ok, [{totals, _, _, _} | _] = Term_1}
                  when Proc == analysis_options ->
                    parse_stream(FD, Tab, [Term_1 | R], totals);
                {ok, [{P, _, _, _} | _] = Term_1} ->
                    parse_stream(FD, Tab, [Term_1 | R], P);
                {ok, {_Callers, {MFA, _, _, _}, _Called} = Term_1}
                  when Proc == totals; is_list(Proc) ->
                    ets:insert(Tab, {{Proc, MFA}, Term_1}),
                    parse_stream(FD, Tab, R, Proc);
                {ok, Term_1} ->
                    {error, [?MODULE, ?LINE, Term_1]};
                E ->
                    E
            end;
        eof ->
            {ok, [Tab, lists:reverse(R)]};
        Error ->
            Error
    end.

parse_term({Callers, Func, Called})
  when is_list(Callers), is_list(Called) ->
    Callers_1 = lists:map(fun parse_clocks/1, Callers),
    Func_1 = parse_clocks(Func),
    Called_1 = lists:map(fun parse_clocks/1, Called),
    Result = {Callers_1, Func_1, Called_1},
    case chk_invariant(Result) of
        ok ->
            {ok, Result};
        Error ->
            Error
    end;
parse_term([{_, _, _, _} = Clocks | Tail]) ->
    {ok, [parse_clocks(Clocks) | Tail]};
parse_term(Term) ->
    {ok, Term}.

parse_clocks({MFA, Cnt, undefined, Own}) ->
    {MFA, Cnt, undefined, round(Own*1000)};
parse_clocks({MFA, Cnt, Acc, Own}) ->
    {MFA, Cnt, round(Acc*1000), round(Own*1000)};
parse_clocks(Clocks) ->
    Clocks.



chk_invariant({Callers, {MFA, Cnt, Acc, Own}, Called} = Term) ->
    {_, Callers_Cnt, Callers_Acc, Callers_Own} = Callers_Sum = sum(Callers),
    %    {_, Called_Cnt, Called_Acc, Called_Own} = Called_Sum = sum(Called),
    case {MFA, 
          lists:keymember(suspend, 1, Callers),
          lists:keymember(garbage_collect, 1, Callers),
          Called} of
        {suspend, false, _, []} ->
            ok;
        {suspend, _, _, _} = Weird ->
            {error, [?MODULE, ?LINE, Weird, Term]};
        {garbage_collect, false, false, []} ->
            ok;
        {garbage_collect, false, false, [{suspend, _, _, _}]} ->
            ok;
        {garbage_collect, _, _, _} = Weird ->
            {error, [?MODULE, ?LINE, Weird, Term]};
        {undefined, false, false, _}
          when Callers == [], Cnt == 0, Acc == 0, Own == 0 ->
            ok;
        {undefined, _, _, _} = Weird ->
            {error, [?MODULE, ?LINE, Weird, Term]};
        {_, _, _, _} ->
            case chk_self_call(Term) of
                true when Callers_Cnt /= Cnt; Callers_Acc /= Acc;
                          Callers_Own /= Own ->
                    {error, [?MODULE, ?LINE, Callers_Sum, Term]};
                % 		true when Called_Acc + Own /= Acc ->
                % 		    io:format("WARNING: ~p:~p, ~p, ~p.~n",
                % 			      [?MODULE, ?LINE, Term, Called_Sum]),
                % 		    {error, [?MODULE, ?LINE, Term, Called_Sum]};
                % 		    ok;
                true ->
                    ok;
                false ->
                    {error, [?MODULE, ?LINE, Term]}
            end
    end.

ts_sub({A, B, C}, {A0, B0, C0}) ->
    ((A - A0)*1000000000000 + (B - B0))*1000000 + C - C0.

sum(Funcs) ->
    {sum, _Cnt, _Acc, _Own} = 
    lists:foldl(
      fun ({_, C1, A1, O1}, {sum, C2, A2, O2}) ->
              {sum, C1+C2, A1+A2, O1+O2}
      end,
      {sum, 0, 0, 0},
      Funcs).

chk_self_call({Callers, {MFA, _Cnt, _Acc, _Own}, Called}) ->
    case lists:keysearch(MFA, 1, Callers) of
        false ->
            true;
        {value, {MFA, C, 0, O}} ->
            case lists:keysearch(MFA, 1, Called) of
                false ->
                    false;
                {value, {MFA, C, 0, O}} ->
                    true;
                {value, _} ->
                    false
            end;
        {value, _} ->
            false
    end.



%%%---------------------------------------------------------------------
%%% Fairly generic support functions
%%%---------------------------------------------------------------------


ets_select_fold(Table, MatchSpec, Limit, Fun, Acc) ->
    ets:safe_fixtable(Table, true),
    ets_select_fold_1(ets:select(Table, MatchSpec, Limit), Fun, Acc).

ets_select_fold_1('$end_of_table', _, Acc) ->
    Acc;
ets_select_fold_1({Matches, Continuation}, Fun, Acc) ->
    ets_select_fold_1(ets:select(Continuation), 
                      Fun,
                      lists:foldl(Fun, Acc, Matches)).


% ets_select_foreach(Table, MatchSpec, Limit, Fun) ->
%     ets:safe_fixtable(Table, true),
%     ets_select_foreach_1(ets:select(Table, MatchSpec, Limit), Fun).

% ets_select_foreach_1('$end_of_table', _) ->
%     ok;
% ets_select_foreach_1({Matches, Continuation}, Fun) ->
%     lists:foreach(Fun, Matches),
%     ets_select_foreach_1(ets:select(Continuation), Fun).


%%%---------------------------------------------------------------------
%%% Simple smulation of fprof used for checking own and acc times for
%%% each function.
%%% The function 'undefined' is ignored
%%%---------------------------------------------------------------------

%% check_own_and_acc_traced(TraceFile, AnalysisFile) ->
%%     check_own_and_acc(TraceFile, AnalysisFile, fun handle_trace_traced/2).

check_own_and_acc(TraceFile, AnalysisFile) ->
    check_own_and_acc(TraceFile, AnalysisFile, fun handle_trace/2).

check_own_and_acc(TraceFile, AnalysisFile, HandlerFun) ->
    dbg:trace_client(file,TraceFile,{HandlerFun,{init,self()}}),
    receive {result,Result} -> 
                compare(Result,get_own_and_acc_from_analysis(AnalysisFile))
    end.

%% handle_trace_traced(Trace, Msg) ->
%%     io:format("handle_trace_traced(~p, ~p).", [Trace, Msg]),
%%     handle_trace(Trace, Msg).

handle_trace(Trace,{init,Parent}) ->
    ?dbg("~p",[start]),
    ets:new(fprof_verify_tab,[named_table]),
    handle_trace(Trace,Parent);
handle_trace({trace_ts,Pid,in,MFA,TS},P) ->
    ?dbg("~p",[{{in,Pid,MFA},get(Pid)}]),
    case get(Pid) of
        [suspend|[suspend|_]=NewStack] ->
            T = ts_sub(TS,get({Pid,last_ts})),
            update_acc(Pid,NewStack,T),
            put(Pid,NewStack);
        [suspend|NewStack] = Stack ->
            T = ts_sub(TS,get({Pid,last_ts})),
            update_acc(Pid,Stack,T),
            put(Pid,NewStack);
        [] ->
            put(Pid,[MFA]),
            insert(Pid,MFA);
        undefined ->
            put(first_ts,TS),
            put(Pid,[MFA]),
            insert(Pid,MFA)
    end,
    put({Pid,last_ts},TS),
    P;
handle_trace({trace_ts,Pid,out,_MfaOrZero,TS},P) ->
    ?dbg("~p",[{{out,Pid,_MfaOrZero},get(Pid)}]),
    T = ts_sub(TS,get({Pid,last_ts})),
    case get(Pid) of
        [suspend|S] = Stack ->
            update_acc(Pid,S,T),
            put(Pid,[suspend|Stack]);
        [MFA|_] = Stack ->
            insert(Pid,suspend),
            update_own(Pid,MFA,T),
            update_acc(Pid,Stack,T),
            put(Pid,[suspend|Stack]);
        [] ->
            insert(Pid,suspend),
            put(Pid,[suspend])
    end,
    put({Pid,last_ts},TS),
    P;
handle_trace({trace_ts,Pid,call,MFA,{cp,Caller},TS},P) ->
    ?dbg("~p",[{{call,Pid,MFA},get(Pid)}]),
    T = ts_sub(TS,get({Pid,last_ts})),
    case get(Pid) of
        [MFA|_] = Stack ->
            %% recursive
            update_own(Pid,MFA,T),
            update_acc(Pid,Stack,T);
        [CallingMFA|_] = Stack when Caller==undefined ->
            insert(Pid,MFA),
            update_own(Pid,CallingMFA,T),
            update_acc(Pid,Stack,T),
            put(Pid,[MFA|Stack]);
        [] when Caller==undefined ->
            insert(Pid,MFA),
            insert(Pid,MFA),
            put(Pid,[MFA]);
        Stack0 ->
            Stack = [CallingMFA|_] = insert_caller(Caller,Stack0,[]),
            insert(Pid,MFA),
            insert(Pid,Caller),
            update_own(Pid,CallingMFA,T),
            update_acc(Pid,Stack,T),
            put(Pid,[MFA|Stack])
    end,
    put({Pid,last_ts},TS),
    P;
handle_trace({trace_ts,Pid,return_to,MFA,TS},P) ->
    ?dbg("~p",[{{return_to,Pid,MFA},get(Pid)}]),
    T = ts_sub(TS,get({Pid,last_ts})),
    case get(Pid) of
        [MFA|_] = Stack ->
            %% recursive
            update_own(Pid,MFA,T),
            update_acc(Pid,Stack,T),
            put(Pid,Stack);
        [ReturnFromMFA,MFA|RestOfStack] = Stack ->
            update_own(Pid,ReturnFromMFA,T),
            update_acc(Pid,Stack,T),
            put(Pid,[MFA|RestOfStack]);
        [ReturnFromMFA|RestOfStack] = Stack ->
            update_own(Pid,ReturnFromMFA,T),
            update_acc(Pid,Stack,T),
            case find_return_to(MFA,RestOfStack) of
                [] when MFA==undefined ->
                    put(Pid,[]);
                [] ->
                    insert(Pid,MFA),
                    put(Pid,[MFA]);
                NewStack ->
                    put(Pid,NewStack)
            end
    end,
    put({Pid,last_ts},TS),
    P;
handle_trace({trace_ts,Pid,gc_start,_,TS},P) ->
    ?dbg("~p",[{{gc_start,Pid},get(Pid)}]),
    case get(Pid) of
        [suspend|_] = Stack ->
            T = ts_sub(TS,get({Pid,last_ts})),
            insert(Pid,garbage_collect),
            update_acc(Pid,Stack,T),
            put(Pid,[garbage_collect|Stack]);
        [CallingMFA|_] = Stack ->
            T = ts_sub(TS,get({Pid,last_ts})),
            insert(Pid,garbage_collect),
            update_own(Pid,CallingMFA,T),
            update_acc(Pid,Stack,T),
            put(Pid,[garbage_collect|Stack]);
        undefined ->
            put(first_ts,TS),
            put(Pid,[garbage_collect]),
            insert(Pid,garbage_collect)
    end,
    put({Pid,last_ts},TS),
    P;
handle_trace({trace_ts,Pid,gc_end,_,TS},P) ->
    ?dbg("~p",[{{gc_end,Pid},get(Pid)}]),
    T = ts_sub(TS,get({Pid,last_ts})),
    case get(Pid) of
        [garbage_collect|RestOfStack] = Stack ->
            update_own(Pid,garbage_collect,T),
            update_acc(Pid,Stack,T),
            put(Pid,RestOfStack)
    end,
    put({Pid,last_ts},TS),
    P;
handle_trace({trace_ts,Pid,spawn,NewPid,{M,F,Args},TS},P) ->
    MFA = {M,F,length(Args)},
    ?dbg("~p",[{{spawn,Pid,NewPid,MFA},get(Pid)}]),
    T = ts_sub(TS,get({Pid,last_ts})),
    put({NewPid,last_ts},TS),
    put(NewPid,[suspend,MFA]),
    insert(NewPid,suspend),
    insert(NewPid,MFA),
    case get(Pid) of
        [SpawningMFA|_] = Stack ->
            update_own(Pid,SpawningMFA,T),
            update_acc(Pid,Stack,T)
    end,
    put({Pid,last_ts},TS),
    P;
handle_trace({trace_ts,Pid,exit,_Reason,TS},P) ->
    ?dbg("~p",[{{exit,Pid,_Reason},get(Pid)}]),
    T = ts_sub(TS,get({Pid,last_ts})),
    case get(Pid) of
        [DyingMFA|_] = Stack ->
            update_own(Pid,DyingMFA,T),
            update_acc(Pid,Stack,T),
            put(Pid,[]);
        [] ->
            ok
    end,
    put({Pid,last_ts},TS),
    P;
handle_trace({trace_ts,_,Link,_,_},P) 
  when Link==link;
       Link==unlink;
       Link==getting_linked;
       Link==getting_unlinked ->
    P;
handle_trace(end_of_trace,P) ->
    ?dbg("~p",['end']),
    Result = ets:tab2list(fprof_verify_tab),
    {TotOwn,ProcOwns} = get_proc_owns(Result,[],0),
    TotAcc = ts_sub(get_last_ts(),get(first_ts)),
    P ! {result,[{totals,TotAcc,TotOwn}|ProcOwns]++Result},
    P;
handle_trace(Other,_P) ->
    exit({unexpected,Other}).

find_return_to(MFA,[MFA|_]=Stack) ->
    Stack;
find_return_to(MFA,[_|Stack]) ->
    find_return_to(MFA,Stack);
find_return_to(_MFA,[]) ->
    [].

insert_caller(MFA,[MFA|Rest],Result) ->
    lists:reverse(Result)++[MFA|Rest];
insert_caller(MFA,[Other|Rest],Result) ->
    insert_caller(MFA,Rest,[Other|Result]);
insert_caller(MFA,[],Result) ->
    lists:reverse([MFA|Result]).

insert(Pid,MFA) ->
    case ets:member(fprof_verify_tab,{Pid,MFA}) of
        false ->
            ets:insert(fprof_verify_tab,{{Pid,MFA},0,0});
        true ->
            ok
    end.

update_own(Pid,MFA,T) ->
    ets:update_counter(fprof_verify_tab,{Pid,MFA},{3,T}).

update_acc(Pid,[MFA|Rest],T) ->
    case lists:member(MFA,Rest) of
        true ->
            %% Only charge one time for recursive functions
            ok;
        false ->
            ets:update_counter(fprof_verify_tab,{Pid,MFA},{2,T})
    end,
    update_acc(Pid,Rest,T);
update_acc(_Pid,[],_T) ->
    ok.


get_last_ts() ->
    get_last_ts(get(),{0,0,0}).
get_last_ts([{{_,last_ts},TS}|Rest],Last) when TS>Last ->
    get_last_ts(Rest,TS);
get_last_ts([_|Rest],Last) ->
    get_last_ts(Rest,Last);
get_last_ts([],Last) ->
    Last.

get_proc_owns([{{Pid,_MFA},_Acc,Own}|Rest],Result,Sum) ->
    NewResult = 
    case lists:keysearch(Pid,1,Result) of
        {value,{Pid,undefined,PidOwn}} ->
            lists:keyreplace(Pid,1,Result,{Pid,undefined,PidOwn+Own});
        false ->
            [{Pid,undefined,Own}|Result]
    end,
    get_proc_owns(Rest,NewResult,Sum+Own);
get_proc_owns([],Result,Sum) ->
    {Sum,Result}.


compare([X|Rest],FprofResult) ->
    FprofResult1 = 
    case lists:member(X,FprofResult) of
        true ->
            ?dbg("~p",[X]),
            lists:delete(X,FprofResult);
        false ->
            case lists:keysearch(element(1,X),1,FprofResult) of
                {value,Fprof} ->
                    put(compare_error,true),
                    io:format("Error: Different values\n"
                              "Fprof:     ~p\n"
                              "Simulator: ~p",[Fprof,X]),
                    lists:delete(Fprof,FprofResult);
                false ->
                    put(compare_error,true),
                    io:format("Error: Missing in fprof: ~p",[X]),
                    FprofResult
            end
    end,
    compare(Rest,FprofResult1);
compare([],Rest) ->
    case {remove_undefined(Rest,[]),get(compare_error)} of
        {[],undefined} -> ok;
        {Error,_} ->
            case Error of
                [] -> ok;
                _ -> io:format("\nMissing in simulator results:\n~p\n",[Error])
            end,
            ct:fail({error,mismatch_between_simulator_and_fprof})
    end.

remove_undefined([{{_Pid,undefined},_,_}|Rest],Result) ->
    remove_undefined(Rest,Result);
remove_undefined([X|Rest],Result) ->
    remove_undefined(Rest,[X|Result]);
remove_undefined([],Result) ->
    Result.

get_own_and_acc_from_analysis(Log) ->
    case file:consult(Log) of
        {ok,[_Options,[{totals,_,TotAcc,TotOwn}]|Rest]} ->
            get_own_and_acc(undefined,Rest,
                            [{totals,m1000(TotAcc),m1000(TotOwn)}]);
        Error ->
            exit({error,{cant_open,Log,Error}})
    end.

get_own_and_acc(_,[[{PidStr,_,Acc,Own}|_]|Rest],Result) ->
    Pid = list_to_pid(PidStr),
    get_own_and_acc(Pid,Rest,[{Pid,m1000(Acc),m1000(Own)}|Result]);
get_own_and_acc(Pid,[{_Callers,{MFA,_,Acc,Own},_Called}|Rest],Result) ->
    get_own_and_acc(Pid,Rest,[{{Pid,MFA},m1000(Acc),m1000(Own)}|Result]);
get_own_and_acc(_,[],Result) ->
    lists:reverse(Result).

m1000(undefined) ->
    undefined;
m1000(X) ->
    round(X*1000).