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authorBjörn Gustavsson <[email protected]>2011-08-25 11:25:29 +0200
committerBjörn Gustavsson <[email protected]>2011-08-25 11:25:29 +0200
commit142700357d3c76aa4c916f0cd5f915a947cbf94c (patch)
tree3af82388a86d708b3185fc142013a459c0201652 /lib/debugger/src/dbg_ieval.erl
parent756a93ca2064b9e0eba3d82a7bd37aeae0f39be1 (diff)
parent26cceb7a0718182e74083b4ad044985e8f624ee2 (diff)
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Merge branch 'bjorn/line-numbers-in-exceptions/OTP-9468' into major
* bjorn/line-numbers-in-exceptions/OTP-9468: (51 commits) debugger: By default, only save non-tail-recursive calls debugger: Add line_number_SUITE debugger: Include line numbers in exceptions Update examples in the documentation to include line numbers Update documentation for erlang:raise/3 and erlang:get_stacktrace/0 beam_lib: Retain the "Line" chunk when stripping BEAM files erl: Add +L to suppress loading of line number information compiler: Add no_line_info for suppressing line/1 instructions exception_SUITE: Test line numbers in exceptions common_test: Use line numbers in exceptions common_test tests: Don't do detailed testing of the stack backtrace test_server: Refactor init_per_testcase/3 into two functions Implement process_info(Pid, current_{location,stacktrace}) beam_emu: Factor out saving of stack trace from save_stacktrace() compiler: Don't create filenames starting with "./" ops.tab: Remove line instructions before tail-recursive calls Lookup and include filenames and line numbers in exceptions Fix decrement of continuation pointers Refactor building of the exception stacktrace BEAM loader: Load the line table ...
Diffstat (limited to 'lib/debugger/src/dbg_ieval.erl')
-rw-r--r--lib/debugger/src/dbg_ieval.erl555
1 files changed, 190 insertions, 365 deletions
diff --git a/lib/debugger/src/dbg_ieval.erl b/lib/debugger/src/dbg_ieval.erl
index 306323f8ea..df725ed9e5 100644
--- a/lib/debugger/src/dbg_ieval.erl
+++ b/lib/debugger/src/dbg_ieval.erl
@@ -20,8 +20,7 @@
-export([eval/3,exit_info/5]).
-export([eval_expr/3]).
--export([check_exit_msg/3,exception/4,in_use_p/2]).
--export([stack_level/0, bindings/1, stack_frame/2, backtrace/1]).
+-export([check_exit_msg/3,exception/4]).
-include("dbg_ieval.hrl").
@@ -71,13 +70,12 @@ exit_info(Int, AttPid, OrigPid, Reason, ExitInfo) ->
case ExitInfo of
{{Mod,Line},Bs,S} ->
- Stack = binary_to_term(S),
- put(stack, Stack),
- Le = stack_level(Stack),
+ dbg_istk:from_external(S),
+ Le = dbg_istk:stack_level(),
dbg_icmd:tell_attached({exit_at, {Mod, Line}, Reason, Le}),
exit_loop(OrigPid, Reason, Bs,#ieval{module=Mod,line=Line});
{} ->
- put(stack, []),
+ dbg_istk:init(),
dbg_icmd:tell_attached({exit_at, null, Reason, 1}),
exit_loop(OrigPid, Reason, erl_eval:new_bindings(),#ieval{})
end.
@@ -142,12 +140,12 @@ check_exit_msg({'DOWN',_,_,_,Reason}, Bs,
undefined when Le =:= 1 -> % died outside interpreted code
{};
undefined when Le > 1 ->
- StackBin = term_to_binary(get(stack)),
- {{Mod, Li}, Bs, StackBin};
+ StackExternal = (dbg_istk:delayed_to_external())(),
+ {{Mod, Li}, Bs, StackExternal};
%% Debugged has terminated due to an exception
- ExitInfo0 ->
- ExitInfo0
+ ExitInfo0 when is_function(ExitInfo0, 0) ->
+ ExitInfo0()
end,
dbg_iserver:cast(get(int), {set_exit_info,self(),ExitInfo}),
@@ -170,30 +168,26 @@ check_exit_msg(_Msg, _Bs, _Ieval) ->
%% and then raise the exception.
%%--------------------------------------------------------------------
exception(Class, Reason, Bs, Ieval) ->
- exception(Class, Reason, fix_stacktrace(1), Bs, Ieval).
-
-exception(Class, Reason, Stacktrace, Bs, #ieval{module=M, line=Line}) ->
- ExitInfo = {{M,Line}, Bs, term_to_binary(get(stack))},
+ exception(Class, Reason, Bs, Ieval, false).
+
+exception(Class, Reason, Bs, Ieval, false) ->
+ do_exception(Class, Reason,
+ dbg_istk:delayed_stacktrace(no_args, Ieval),
+ Bs, Ieval);
+exception(Class, Reason, Bs, Ieval, true) ->
+ do_exception(Class, Reason,
+ dbg_istk:delayed_stacktrace(include_args, Ieval),
+ Bs, Ieval).
+
+do_exception(Class, Reason, Stacktrace, Bs, #ieval{module=M, line=Line}) ->
+ StackFun = dbg_istk:delayed_to_external(),
+ ExitInfo = fun() ->
+ {{M,Line},Bs,StackFun()}
+ end,
put(exit_info, ExitInfo),
put(stacktrace, Stacktrace),
erlang:Class(Reason).
-%%--------------------------------------------------------------------
-%% in_use_p(Mod, Cm) -> boolean()
-%% Mod = Cm = atom()
-%% Returns true if Mod is found on the stack, otherwise false.
-%%--------------------------------------------------------------------
-in_use_p(Mod, Mod) -> true;
-in_use_p(Mod, _Cm) ->
- case get(trace_stack) of
- false -> true;
- _ -> % all | no_tail
- lists:any(fun({_,{M,_,_,_}}) when M =:= Mod -> true;
- (_) -> false
- end,
- get(stack))
- end.
-
%%====================================================================
%% Internal functions
%%====================================================================
@@ -225,7 +219,7 @@ meta(Int, Debugged, M, F, As) ->
put(cache, []),
put(next_break, Status), % break | running (other values later)
put(self, Debugged), % pid() interpreted process
- put(stack, []),
+ dbg_istk:init(),
put(stacktrace, []),
put(trace_stack, dbg_iserver:call(Int, get_stack_trace)),
put(trace, false), % bool() Trace on/off
@@ -243,8 +237,7 @@ meta(Int, Debugged, M, F, As) ->
debugged_cmd(Cmd, Bs, Ieval) ->
Debugged = get(self),
- Stacktrace = fix_stacktrace(2),
- Debugged ! {sys, self(), {command,Cmd,Stacktrace}},
+ Debugged ! {sys, self(), {command,Cmd}},
meta_loop(Debugged, Bs, Ieval).
meta_loop(Debugged, Bs, #ieval{level=Le} = Ieval) ->
@@ -257,12 +250,17 @@ meta_loop(Debugged, Bs, #ieval{level=Le} = Ieval) ->
{value, Val, Bs};
{sys, Debugged, {value,Val,Bs2}} ->
{value, Val, Bs2};
- {sys, Debugged, {exception,{Class,Reason,Stacktrace}}} ->
+ {sys, Debugged, {exception,{Class,Reason,Stk}}} ->
case get(exit_info) of
- %% Error occured outside interpreted code
+ %% Error occurred outside of interpreted code.
undefined ->
- exception(Class,Reason,Stacktrace,Bs,Ieval);
+ MakeStk0 = dbg_istk:delayed_stacktrace(),
+ MakeStk = fun(Depth0) ->
+ Depth = max(0, Depth0 - length(Stk)),
+ Stk ++ MakeStk0(Depth)
+ end,
+ do_exception(Class, Reason, MakeStk, Bs, Ieval);
%% Error must have occured within a re-entry to
%% interpreted code, simply raise the exception
@@ -275,7 +273,7 @@ meta_loop(Debugged, Bs, #ieval{level=Le} = Ieval) ->
%% Reset process dictionary
%% This is really only necessary if the process left
%% interpreted code at a call level > 1
- put(stack, []),
+ dbg_istk:init(),
put(stacktrace, []),
put(exit_info, undefined),
@@ -313,177 +311,6 @@ exit_loop(OrigPid, Reason, Bs, Ieval) ->
exit_loop(OrigPid, Reason, Bs, Ieval)
end.
-%%--Stack emulation---------------------------------------------------
-
-%% We keep track of a call stack that is used for
-%% 1) saving stack frames that can be inspected from an Attached
-%% Process GUI (using dbg_icmd:get(Meta, stack_frame, {Dir, SP})
-%% 2) generate an approximation of regular stacktrace -- sent to
-%% Debugged when it should raise an exception or evaluate a
-%% function (since it might possible raise an exception)
-%%
-%% Stack = [Entry]
-%% Entry = {Le, {MFA, Where, Bs}}
-%% Le = int() % current call level
-%% MFA = {M,F,Args} % called function (or fun)
-%% | {Fun,Args} %
-%% Where = {M,Li} % from where (module+line) function is called
-%% Bs = bindings() % current variable bindings
-%%
-%% How to push depends on the "Stack Trace" option (value saved in
-%% process dictionary item 'trace_stack').
-%% all - everything is pushed
-%% no_tail - tail recursive push
-%% false - nothing is pushed
-%% Whenever a function returns, the corresponding call frame is popped.
-
-push(MFA, Bs, #ieval{level=Le,module=Cm,line=Li,last_call=Lc}) ->
- Entry = {Le, {MFA, {Cm,Li}, Bs}},
- case get(trace_stack) of
- false -> ignore;
- no_tail when Lc ->
- case get(stack) of
- [] -> put(stack, [Entry]);
- [_Entry|Entries] -> put(stack, [Entry|Entries])
- end;
- _ -> % all | no_tail when Lc =:= false
- put(stack, [Entry|get(stack)])
- end.
-
-pop() ->
- case get(trace_stack) of
- false -> ignore;
- _ -> % all � no_tail
- case get(stack) of
- [_Entry|Entries] ->
- put(stack, Entries);
- [] ->
- ignore
- end
- end.
-
-pop(Le) ->
- case get(trace_stack) of
- false -> ignore;
- _ -> % all | no_tail
- put(stack, pop(Le, get(stack)))
- end.
-
-pop(Level, [{Le, _}|Stack]) when Level=<Le ->
- pop(Level, Stack);
-pop(_Level, Stack) ->
- Stack.
-
-
-%% stack_level() -> Le
-%% stack_level(Stack) -> Le
-%% Top call level
-stack_level() ->
- stack_level(get(stack)).
-
-stack_level([]) -> 1;
-stack_level([{Le,_}|_]) -> Le.
-
-%% fix_stacktrace(Start) -> Stacktrace
-%% Start = 1|2
-%% Stacktrace = [{M,F,Args|Arity} | {Fun,Args}]
-%% Convert internal stack format to imitation of regular stacktrace.
-%% Max three elements, no repeated (recursive) calls to the same
-%% function and convert argument lists to arity for all but topmost
-%% entry (and funs).
-%% 'Start' indicates where at get(stack) to start. This somewhat ugly
-%% solution is because fix_stacktrace has two uses: 1) to imitate
-%% the stacktrace in the case of an exception in the interpreted code,
-%% in which case the current call (top of the stack = first of the list)
-%% should be included, and 2) to send a current stacktrace to Debugged
-%% when evaluation passes into non-interpreted code, in which case
-%% the current call should NOT be included (as it is Debugged which
-%% will make the actual function call).
-fix_stacktrace(Start) ->
- case fix_stacktrace2(sublist(get(stack), Start, 3)) of
- [] ->
- [];
- [H|T] ->
- [H|args2arity(T)]
- end.
-
-sublist([], _Start, _Length) ->
- []; % workaround, lists:sublist([],2,3) fails
-sublist(L, Start, Length) ->
- lists:sublist(L, Start, Length).
-
-fix_stacktrace2([{_,{{M,F,As1},_,_}}, {_,{{M,F,As2},_,_}}|_])
- when length(As1) =:= length(As2) ->
- [{M,F,As1}];
-fix_stacktrace2([{_,{{Fun,As1},_,_}}, {_,{{Fun,As2},_,_}}|_])
- when length(As1) =:= length(As2) ->
- [{Fun,As1}];
-fix_stacktrace2([{_,{MFA,_,_}}|Entries]) ->
- [MFA|fix_stacktrace2(Entries)];
-fix_stacktrace2([]) ->
- [].
-
-args2arity([{M,F,As}|Entries]) when is_list(As) ->
- [{M,F,length(As)}|args2arity(Entries)];
-args2arity([Entry|Entries]) ->
- [Entry|args2arity(Entries)];
-args2arity([]) ->
- [].
-
-%% bindings(SP) -> Bs
-%% SP = Le % stack pointer
-%% Return the bindings for the specified call level
-bindings(SP) ->
- bindings(SP, get(stack)).
-
-bindings(SP, [{SP,{_MFA,_Wh,Bs}}|_]) ->
- Bs;
-bindings(SP, [_Entry|Entries]) ->
- bindings(SP, Entries);
-bindings(_SP, []) ->
- erl_eval:new_bindings().
-
-%% stack_frame(Dir, SP) -> {Le, Where, Bs} | top | bottom
-%% Dir = up | down
-%% Where = {Cm, Li}
-%% Cm = Module | undefined % module
-%% Li = int() | -1 % line number
-%% Bs = bindings()
-%% Return stack frame info one step up/down from given stack pointer
-%% up = to lower call levels
-%% down = to higher call levels
-stack_frame(up, SP) ->
- stack_frame(SP, up, get(stack));
-stack_frame(down, SP) ->
- stack_frame(SP, down, lists:reverse(get(stack))).
-
-stack_frame(SP, up, [{Le, {_MFA,Where,Bs}}|_]) when Le<SP ->
- {Le, Where, Bs};
-stack_frame(SP, down, [{Le, {_MFA,Where,Bs}}|_]) when Le>SP ->
- {Le, Where, Bs};
-stack_frame(SP, Dir, [{SP, _}|Stack]) ->
- case Stack of
- [{Le, {_MFA,Where,Bs}}|_] ->
- {Le, Where, Bs};
- [] when Dir =:= up ->
- top;
- [] when Dir =:= down ->
- bottom
- end;
-stack_frame(SP, Dir, [_Entry|Stack]) ->
- stack_frame(SP, Dir, Stack).
-
-%% backtrace(HowMany) -> Backtrace
-%% HowMany = all | int()
-%% Backtrace = {Le, MFA}
-%% Return all/the last N called functions, in reversed call order
-backtrace(HowMany) ->
- Stack = case HowMany of
- all -> get(stack);
- N -> lists:sublist(get(stack), N)
- end,
- [{Le, MFA} || {Le,{MFA,_Wh,_Bs}} <- Stack].
-
%%--Trace function----------------------------------------------------
%%--------------------------------------------------------------------
@@ -558,7 +385,7 @@ format_args1([]) ->
%% Mimic catch behaviour
catch_value(error, Reason) ->
- {'EXIT',{Reason,get(stacktrace)}};
+ {'EXIT',{Reason,get_stacktrace()}};
catch_value(exit, Reason) ->
{'EXIT',Reason};
catch_value(throw, Reason) ->
@@ -570,11 +397,13 @@ catch_value(throw, Reason) ->
%% Top level function of meta evaluator.
%% Return message to be replied to the target process.
%%--------------------------------------------------------------------
-eval_mfa(Debugged, M, F, As, Ieval) ->
+eval_mfa(Debugged, M, F, As, #ieval{level=Le}=Ieval0) ->
Int = get(int),
Bs = erl_eval:new_bindings(),
- try eval_function(M,F,As,Bs,extern,Ieval#ieval{last_call=true}) of
+ Ieval = Ieval0#ieval{level=Le+1,top=true},
+ try do_eval_function(M, F, As, Bs, extern, Ieval) of
{value, Val, _Bs} ->
+ trace(return, {Le,Val}),
{ready, Val}
catch
exit:{Debugged, Reason} ->
@@ -582,76 +411,68 @@ eval_mfa(Debugged, M, F, As, Ieval) ->
exit:{Int, Reason} ->
exit(Reason);
Class:Reason ->
- {exception, {Class, Reason, get(stacktrace)}}
+ {exception, {Class, Reason, get_stacktrace()}}
+ end.
+
+eval_function(Mod, Name, As, Bs, Called, Ieval0, Lc) ->
+ Tail = Lc andalso get(trace_stack) =:= no_tail,
+ case Tail of
+ false ->
+ Ieval = dbg_istk:push(Bs, Ieval0, Lc),
+ {value,Val,_} = do_eval_function(Mod, Name, As, Bs, Called, Ieval),
+ dbg_istk:pop(),
+ trace(return, {Ieval#ieval.level,Val}),
+ {value,Val,Bs};
+ true ->
+ do_eval_function(Mod, Name, As, Bs, Called, Ieval0)
end.
-eval_function(Mod, Fun, As0, Bs0, _Called, Ieval) when is_function(Fun);
- Mod =:= ?MODULE,
- Fun =:= eval_fun ->
- #ieval{level=Le, line=Li, last_call=Lc} = Ieval,
+do_eval_function(Mod, Fun, As0, Bs0, _, Ieval0) when is_function(Fun);
+ Mod =:= ?MODULE,
+ Fun =:= eval_fun ->
+ #ieval{level=Le,line=Li,top=Top} = Ieval0,
case lambda(Fun, As0) of
- {Cs,Module,Name,As,Bs} ->
- push({Module,Name,As}, Bs0, Ieval),
+ {[{clause,Fc,_,_,_}|_]=Cs,Module,Name,As,Bs} ->
+ Ieval = Ieval0#ieval{module=Module,function=Name,
+ arguments=As0,line=Fc},
trace(call_fun, {Le,Li,Name,As}),
- {value, Val, _Bs} =
- fnk_clauses(Cs, Module, Name, As, Bs,
- Ieval#ieval{level=Le+1}),
- pop(),
- trace(return, {Le,Val}),
- {value, Val, Bs0};
+ fnk_clauses(Cs, As, Bs, Ieval);
- not_interpreted when Lc -> % We are leaving interpreted code
+ not_interpreted when Top -> % We are leaving interpreted code
trace(call_fun, {Le,Li,Fun,As0}),
{value, {dbg_apply,erlang,apply,[Fun,As0]}, Bs0};
not_interpreted ->
- push({Fun,As0}, Bs0, Ieval),
trace(call_fun, {Le,Li,Fun,As0}),
- {value, Val, _Bs} =
- debugged_cmd({apply,erlang,apply,[Fun,As0]},Bs0,
- Ieval#ieval{level=Le+1}),
- pop(),
- trace(return, {Le,Val}),
- {value, Val, Bs0};
+ debugged_cmd({apply,erlang,apply,[Fun,As0]}, Bs0, Ieval0);
{error,Reason} ->
%% It's ok not to push anything in this case, the error
%% reason contains information about the culprit
%% ({badarity,{{Mod,Name},As}})
- exception(error, Reason, Bs0, Ieval)
+ exception(error, Reason, Bs0, Ieval0)
end;
%% Common Test adaptation
-eval_function(ct_line, line, As, Bs, extern, #ieval{level=Le}=Ieval) ->
+do_eval_function(ct_line, line, As, Bs, extern, #ieval{level=Le}=Ieval) ->
debugged_cmd({apply,ct_line,line,As}, Bs, Ieval#ieval{level=Le+1}),
{value, ignore, Bs};
-eval_function(Mod, Name, As0, Bs0, Called, Ieval) ->
- #ieval{level=Le, line=Li, last_call=Lc} = Ieval,
-
- push({Mod,Name,As0}, Bs0, Ieval),
+do_eval_function(Mod, Name, As0, Bs0, Called, Ieval0) ->
+ #ieval{level=Le,line=Li,top=Top} = Ieval0,
trace(call, {Called, {Le,Li,Mod,Name,As0}}),
-
+ Ieval = Ieval0#ieval{module=Mod,function=Name,arguments=As0},
case get_function(Mod, Name, As0, Called) of
- Cs when is_list(Cs) ->
- {value, Val, _Bs} =
- fnk_clauses(Cs, Mod, Name, As0, erl_eval:new_bindings(),
- Ieval#ieval{level=Le+1}),
- pop(),
- trace(return, {Le,Val}),
- {value, Val, Bs0};
+ [{clause,FcLine,_,_,_}|_]=Cs ->
+ fnk_clauses(Cs, As0, erl_eval:new_bindings(),
+ Ieval#ieval{line=FcLine});
- not_interpreted when Lc -> % We are leaving interpreted code
+ not_interpreted when Top -> % We are leaving interpreted code
{value, {dbg_apply,Mod,Name,As0}, Bs0};
not_interpreted ->
- {value, Val, _Bs} =
- debugged_cmd({apply,Mod,Name,As0}, Bs0,
- Ieval#ieval{level=Le+1}),
- pop(),
- trace(return, {Le,Val}),
- {value, Val, Bs0};
+ debugged_cmd({apply,Mod,Name,As0}, Bs0, Ieval);
undef ->
- exception(error, undef, Bs0, Ieval)
+ exception(error, undef, Bs0, Ieval, true)
end.
lambda(eval_fun, [Cs,As,Bs,{Mod,Name}=F]) ->
@@ -752,23 +573,21 @@ cached(Key) ->
%% Try to find a matching function clause
%% #ieval.level is set, the other fields must be set in this function
-fnk_clauses([{clause,Line,Pars,Gs,Body}|Cs], M, F, As, Bs0, Ieval) ->
+fnk_clauses([{clause,Line,Pars,Gs,Body}|Cs], As, Bs0, Ieval) ->
case head_match(Pars, As, [], Bs0) of
{match,Bs1} ->
Bs = add_bindings(Bs1, Bs0),
case guard(Gs, Bs) of
true ->
- seq(Body, Bs,
- Ieval#ieval{line=Line,
- module=M,function=F,arguments=As});
+ seq(Body, Bs, Ieval#ieval{line=Line});
false ->
- fnk_clauses(Cs, M, F, As, Bs0, Ieval)
+ fnk_clauses(Cs, As, Bs0, Ieval)
end;
nomatch ->
- fnk_clauses(Cs, M, F, As, Bs0, Ieval)
+ fnk_clauses(Cs, As, Bs0, Ieval)
end;
-fnk_clauses([], _M, _F, _As, Bs, Ieval) ->
- exception(error, function_clause, Bs, Ieval).
+fnk_clauses([], _As, Bs, Ieval) ->
+ exception(error, function_clause, Bs, Ieval, true).
seq([E], Bs0, Ieval) ->
case dbg_icmd:cmd(E, Bs0, Ieval) of
@@ -782,7 +601,7 @@ seq([E|Es], Bs0, Ieval) ->
{skip,Bs} ->
seq(Es, Bs, Ieval);
Bs1 ->
- {value,_,Bs} = expr(E, Bs1, Ieval#ieval{last_call=false}),
+ {value,_,Bs} = expr(E, Bs1, Ieval#ieval{top=false}),
seq(Es, Bs, Ieval)
end;
seq([], Bs, _) ->
@@ -804,10 +623,9 @@ expr({value,Val}, Bs, _Ieval) -> % Special case straight values
%% List
expr({cons,Line,H0,T0}, Bs0, Ieval0) ->
- Ieval = Ieval0#ieval{line=Line},
- Ieval1 = Ieval#ieval{last_call=false},
- {value,H,Bs1} = expr(H0,Bs0,Ieval1),
- {value,T,Bs2} = expr(T0,Bs0,Ieval1),
+ Ieval = Ieval0#ieval{line=Line,top=false},
+ {value,H,Bs1} = expr(H0, Bs0, Ieval),
+ {value,T,Bs2} = expr(T0, Bs0, Ieval),
{value,[H|T],merge_bindings(Bs2, Bs1, Ieval)};
%% Tuple
@@ -821,12 +639,12 @@ expr({block,Line,Es},Bs,Ieval) ->
%% Catch statement
expr({'catch',Line,Expr}, Bs0, Ieval) ->
- try expr(Expr, Bs0, Ieval#ieval{line=Line, last_call=false})
+ try expr(Expr, Bs0, Ieval#ieval{line=Line, top=false})
catch
Class:Reason ->
%% Exception caught, reset exit info
put(exit_info, undefined),
- pop(Ieval#ieval.level),
+ dbg_istk:pop(Ieval#ieval.level),
Value = catch_value(Class, Reason),
trace(return, {Ieval#ieval.level,Value}),
{value, Value, Bs0}
@@ -835,7 +653,7 @@ expr({'catch',Line,Expr}, Bs0, Ieval) ->
%% Try-catch statement
expr({'try',Line,Es,CaseCs,CatchCs,[]}, Bs0, Ieval0) ->
Ieval = Ieval0#ieval{line=Line},
- try seq(Es, Bs0, Ieval#ieval{last_call=false}) of
+ try seq(Es, Bs0, Ieval#ieval{top=false}) of
{value,Val,Bs} = Value ->
case CaseCs of
[] -> Value;
@@ -848,7 +666,7 @@ expr({'try',Line,Es,CaseCs,CatchCs,[]}, Bs0, Ieval0) ->
end;
expr({'try',Line,Es,CaseCs,CatchCs,As}, Bs0, Ieval0) ->
Ieval = Ieval0#ieval{line=Line},
- try seq(Es, Bs0, Ieval#ieval{last_call=false}) of
+ try seq(Es, Bs0, Ieval#ieval{top=false}) of
{value,Val,Bs} = Value ->
case CaseCs of
[] -> Value;
@@ -859,13 +677,13 @@ expr({'try',Line,Es,CaseCs,CatchCs,As}, Bs0, Ieval0) ->
Class:Reason when CatchCs =/= [] ->
catch_clauses({Class,Reason,[]}, CatchCs, Bs0, Ieval)
after
- seq(As, Bs0, Ieval#ieval{last_call=false})
+ seq(As, Bs0, Ieval#ieval{top=false})
end;
%% Case statement
expr({'case',Line,E,Cs}, Bs0, Ieval) ->
{value,Val,Bs} =
- expr(E, Bs0, Ieval#ieval{line=Line, last_call=false}),
+ expr(E, Bs0, Ieval#ieval{line=Line, top=false}),
case_clauses(Val, Cs, Bs, case_clause, Ieval#ieval{line=Line});
%% If statement
@@ -874,20 +692,20 @@ expr({'if',Line,Cs}, Bs, Ieval) ->
%% Andalso/orelse
expr({'andalso',Line,E1,E2}, Bs, Ieval) ->
- case expr(E1, Bs, Ieval#ieval{line=Line, last_call=false}) of
+ case expr(E1, Bs, Ieval#ieval{line=Line, top=false}) of
{value,false,_}=Res ->
Res;
{value,true,_} ->
- expr(E2, Bs, Ieval#ieval{line=Line, last_call=false});
+ expr(E2, Bs, Ieval#ieval{line=Line, top=false});
{value,Val,Bs} ->
exception(error, {badarg,Val}, Bs, Ieval)
end;
expr({'orelse',Line,E1,E2}, Bs, Ieval) ->
- case expr(E1, Bs, Ieval#ieval{line=Line, last_call=false}) of
+ case expr(E1, Bs, Ieval#ieval{line=Line, top=false}) of
{value,true,_}=Res ->
Res;
{value,false,_} ->
- expr(E2, Bs, Ieval#ieval{line=Line, last_call=false});
+ expr(E2, Bs, Ieval#ieval{line=Line, top=false});
{value,Val,_} ->
exception(error, {badarg,Val}, Bs, Ieval)
end;
@@ -895,7 +713,7 @@ expr({'orelse',Line,E1,E2}, Bs, Ieval) ->
%% Matching expression
expr({match,Line,Lhs,Rhs0}, Bs0, Ieval0) ->
Ieval = Ieval0#ieval{line=Line},
- {value,Rhs,Bs1} = expr(Rhs0, Bs0, Ieval#ieval{last_call=false}),
+ {value,Rhs,Bs1} = expr(Rhs0, Bs0, Ieval#ieval{top=false}),
case match(Lhs, Rhs, Bs1) of
{match,Bs} ->
{value,Rhs,Bs};
@@ -951,21 +769,21 @@ expr({make_fun,Line,Name,Cs}, Bs, #ieval{module=Module}=Ieval) ->
{value,Fun,Bs};
%% Common test adaptation
-expr({call_remote,0,ct_line,line,As0}, Bs0, Ieval0) ->
+expr({call_remote,0,ct_line,line,As0,Lc}, Bs0, Ieval0) ->
{As,_Bs} = eval_list(As0, Bs0, Ieval0),
- eval_function(ct_line, line, As, Bs0, extern, Ieval0);
+ eval_function(ct_line, line, As, Bs0, extern, Ieval0, Lc);
%% Local function call
-expr({local_call,Line,F,As0}, Bs0, #ieval{module=M} = Ieval0) ->
+expr({local_call,Line,F,As0,Lc}, Bs0, #ieval{module=M} = Ieval0) ->
Ieval = Ieval0#ieval{line=Line},
{As,Bs} = eval_list(As0, Bs0, Ieval),
- eval_function(M, F, As, Bs, local, Ieval);
+ eval_function(M, F, As, Bs, local, Ieval, Lc);
%% Remote function call
-expr({call_remote,Line,M,F,As0}, Bs0, Ieval0) ->
+expr({call_remote,Line,M,F,As0,Lc}, Bs0, Ieval0) ->
Ieval = Ieval0#ieval{line=Line},
{As,Bs} = eval_list(As0, Bs0, Ieval),
- eval_function(M, F, As, Bs, extern, Ieval);
+ eval_function(M, F, As, Bs, extern, Ieval, Lc);
%% Emulated semantics of some BIFs
expr({dbg,Line,self,[]}, Bs, #ieval{level=Le}) ->
@@ -975,9 +793,28 @@ expr({dbg,Line,self,[]}, Bs, #ieval{level=Le}) ->
{value,Self,Bs};
expr({dbg,Line,get_stacktrace,[]}, Bs, #ieval{level=Le}) ->
trace(bif, {Le,Line,erlang,get_stacktrace,[]}),
- Stacktrace = get(stacktrace),
+ Stacktrace = get_stacktrace(),
trace(return, {Le,Stacktrace}),
{value,Stacktrace,Bs};
+expr({dbg,Line,raise,As0}, Bs0, #ieval{level=Le}=Ieval0) ->
+ %% Since erlang:get_stacktrace/0 is emulated, we will
+ %% need to emulate erlang:raise/3 too so that we can
+ %% capture the stacktrace.
+ Ieval = Ieval0#ieval{line=Line},
+ {[Class,Reason,Stk0]=As,Bs} = eval_list(As0, Bs0, Ieval),
+ trace(bif, {Le,Line,erlang,raise,As}),
+ try
+ %% Evaluate raise/3 for error checking and
+ %% truncating of the stacktrace to the correct depth.
+ Error = erlang:raise(Class, Reason, Stk0),
+ trace(return, {Le,Error}),
+ {value,Error,Bs}
+ catch
+ _:_ ->
+ Stk = erlang:get_stacktrace(), %Possibly truncated.
+ StkFun = fun(_) -> Stk end,
+ do_exception(Class, Reason, StkFun, Bs, Ieval)
+ end;
expr({dbg,Line,throw,As0}, Bs0, #ieval{level=Le}=Ieval0) ->
Ieval = Ieval0#ieval{line=Line},
{[Term],Bs} = eval_list(As0, Bs0, Ieval),
@@ -988,11 +825,6 @@ expr({dbg,Line,error,As0}, Bs0, #ieval{level=Le}=Ieval0) ->
{[Term],Bs} = eval_list(As0, Bs0, Ieval),
trace(bif, {Le,Line,erlang,error,[Term]}),
exception(error, Term, Bs, Ieval);
-expr({dbg,Line,fault,As0}, Bs0, #ieval{level=Le}=Ieval0) ->
- Ieval = Ieval0#ieval{line=Line},
- {[Term],Bs} = eval_list(As0, Bs0, Ieval),
- trace(bif, {Le,Line,erlang,fault,[Term]}),
- exception(fault, Term, Bs, Ieval);
expr({dbg,Line,exit,As0}, Bs0, #ieval{level=Le}=Ieval0) ->
Ieval = Ieval0#ieval{line=Line},
{[Term],Bs} = eval_list(As0, Bs0, Ieval),
@@ -1001,36 +833,26 @@ expr({dbg,Line,exit,As0}, Bs0, #ieval{level=Le}=Ieval0) ->
%% Call to "safe" BIF, ie a BIF that can be executed in Meta process
expr({safe_bif,Line,M,F,As0}, Bs0, #ieval{level=Le}=Ieval0) ->
- Ieval = Ieval0#ieval{line=Line},
- {As,Bs} = eval_list(As0, Bs0, Ieval),
+ Ieval1 = Ieval0#ieval{line=Line},
+ {As,Bs} = eval_list(As0, Bs0, Ieval1),
trace(bif, {Le,Line,M,F,As}),
- push({M,F,As}, Bs0, Ieval),
+ Ieval2 = dbg_istk:push(Bs0, Ieval1, false),
+ Ieval = Ieval2#ieval{module=M,function=F,arguments=As,line=-1},
{_,Value,_} = Res = safe_bif(M, F, As, Bs, Ieval),
trace(return, {Le,Value}),
- pop(),
+ dbg_istk:pop(),
Res;
%% Call to a BIF that must be evaluated in the correct process
expr({bif,Line,M,F,As0}, Bs0, #ieval{level=Le}=Ieval0) ->
- Ieval = Ieval0#ieval{line=Line},
- {As,Bs} = eval_list(As0, Bs0, Ieval),
+ Ieval1 = Ieval0#ieval{line=Line},
+ {As,Bs} = eval_list(As0, Bs0, Ieval1),
trace(bif, {Le,Line,M,F,As}),
- push({M,F,As}, Bs0, Ieval),
- {_,Value,_} =
- Res = debugged_cmd({apply,M,F,As}, Bs, Ieval#ieval{level=Le+1}),
+ Ieval2 = dbg_istk:push(Bs0, Ieval1, false),
+ Ieval = Ieval2#ieval{module=M,function=F,arguments=As,line=-1},
+ {_,Value,_} = Res = debugged_cmd({apply,M,F,As}, Bs, Ieval),
trace(return, {Le,Value}),
- pop(),
- Res;
-
-%% Call to a BIF that spawns a new process
-expr({spawn_bif,Line,M,F,As0}, Bs0, #ieval{level=Le}=Ieval0) ->
- Ieval = Ieval0#ieval{line=Line},
- {As,Bs} = eval_list(As0, Bs0, Ieval),
- trace(bif, {Le,Line,M,F,As}),
- push({M,F,As}, Bs0, Ieval),
- Res = debugged_cmd({apply,M,F,As}, Bs,Ieval#ieval{level=Le+1}),
- trace(return, {Le,Res}),
- pop(),
+ dbg_istk:pop(),
Res;
%% Call to an operation
@@ -1046,7 +868,7 @@ expr({op,Line,Op,As0}, Bs0, Ieval0) ->
end;
%% apply/2 (fun)
-expr({apply_fun,Line,Fun0,As0}, Bs0, #ieval{level=Le}=Ieval0) ->
+expr({apply_fun,Line,Fun0,As0,Lc}, Bs0, #ieval{level=Le}=Ieval0) ->
Ieval = Ieval0#ieval{line=Line},
FunValue = case expr(Fun0, Bs0, Ieval) of
{value,{dbg_apply,Mx,Fx,Asx},Bsx} ->
@@ -1058,31 +880,20 @@ expr({apply_fun,Line,Fun0,As0}, Bs0, #ieval{level=Le}=Ieval0) ->
case FunValue of
{value,Fun,Bs1} when is_function(Fun) ->
{As,Bs} = eval_list(As0, Bs1, Ieval),
- eval_function(undefined, Fun, As, Bs, extern, Ieval);
+ eval_function(undefined, Fun, As, Bs, extern, Ieval, Lc);
{value,{M,F},Bs1} when is_atom(M), is_atom(F) ->
{As,Bs} = eval_list(As0, Bs1, Ieval),
- eval_function(M, F, As, Bs, extern, Ieval);
+ eval_function(M, F, As, Bs, extern, Ieval, Lc);
{value,BadFun,Bs1} ->
exception(error, {badfun,BadFun}, Bs1, Ieval)
end;
%% apply/3
-expr({apply,Line,As0}, Bs0, Ieval0) ->
+expr({apply,Line,As0,Lc}, Bs0, Ieval0) ->
Ieval = Ieval0#ieval{line=Line},
{[M,F,As],Bs} = eval_list(As0, Bs0, Ieval),
- eval_function(M, F, As, Bs, extern, Ieval);
+ eval_function(M, F, As, Bs, extern, Ieval, Lc);
-%% Mod:module_info/0,1
-expr({module_info_0,_,Mod}, Bs, _Ieval) ->
- {value,[{compile,module_info(Mod,compile)},
- {attributes,module_info(Mod,attributes)},
- {imports,module_info(Mod,imports)},
- {exports,module_info(Mod,exports)}],Bs};
-expr({module_info_1,Line,Mod,[As0]}, Bs0, Ieval0) ->
- Ieval = Ieval0#ieval{line=Line},
- {value,What,Bs} = expr(As0, Bs0, Ieval),
- {value,module_info(Mod, What),Bs};
-
%% Receive statement
expr({'receive',Line,Cs}, Bs0, #ieval{level=Le}=Ieval) ->
trace(receivex, {Le,false}),
@@ -1091,7 +902,7 @@ expr({'receive',Line,Cs}, Bs0, #ieval{level=Le}=Ieval) ->
%% Receive..after statement
expr({'receive',Line,Cs,To,ToExprs}, Bs0, #ieval{level=Le}=Ieval0) ->
Ieval = Ieval0#ieval{line=Line},
- {value,ToVal,ToBs} = expr(To, Bs0, Ieval#ieval{last_call=false}),
+ {value,ToVal,ToBs} = expr(To, Bs0, Ieval#ieval{top=false}),
trace(receivex, {Le,true}),
check_timeoutvalue(ToVal, ToBs, To, Ieval),
{Stamp,_} = statistics(wall_clock),
@@ -1101,7 +912,7 @@ expr({'receive',Line,Cs,To,ToExprs}, Bs0, #ieval{level=Le}=Ieval0) ->
%% Send (!)
expr({send,Line,To0,Msg0}, Bs0, Ieval0) ->
Ieval = Ieval0#ieval{line=Line},
- Ieval1 = Ieval#ieval{last_call=false},
+ Ieval1 = Ieval#ieval{top=false},
{value,To,Bs1} = expr(To0, Bs0, Ieval1),
{value,Msg,Bs2} = expr(Msg0, Bs0, Ieval1),
Bs = merge_bindings(Bs2, Bs1, Ieval),
@@ -1110,10 +921,15 @@ expr({send,Line,To0,Msg0}, Bs0, Ieval0) ->
%% Binary
expr({bin,Line,Fs}, Bs0, Ieval0) ->
Ieval = Ieval0#ieval{line=Line},
- eval_bits:expr_grp(Fs, Bs0,
- fun (E, B) -> expr(E, B, Ieval) end,
- [],
- false);
+ try
+ eval_bits:expr_grp(Fs, Bs0,
+ fun (E, B) -> expr(E, B, Ieval) end,
+ [],
+ false)
+ catch
+ Class:Reason ->
+ exception(Class, Reason, Bs0, Ieval)
+ end;
%% List comprehension
expr({lc,_Line,E,Qs}, Bs, Ieval) ->
@@ -1138,12 +954,12 @@ eval_lc(E, Qs, Bs, Ieval) ->
eval_lc1(E, [{generate,Line,P,L0}|Qs], Bs0, Ieval0) ->
Ieval = Ieval0#ieval{line=Line},
- {value,L1,Bs1} = expr(L0, Bs0, Ieval#ieval{last_call=false}),
+ {value,L1,Bs1} = expr(L0, Bs0, Ieval#ieval{top=false}),
CompFun = fun(NewBs) -> eval_lc1(E, Qs, NewBs, Ieval) end,
eval_generate(L1, P, Bs1, CompFun, Ieval);
eval_lc1(E, [{b_generate,Line,P,L0}|Qs], Bs0, Ieval0) ->
Ieval = Ieval0#ieval{line=Line},
- {value,Bin,_} = expr(L0, Bs0, Ieval#ieval{last_call=false}),
+ {value,Bin,_} = expr(L0, Bs0, Ieval#ieval{top=false}),
CompFun = fun(NewBs) -> eval_lc1(E, Qs, NewBs, Ieval) end,
eval_b_generate(Bin, P, Bs0, CompFun, Ieval);
eval_lc1(E, [{guard,Q}|Qs], Bs0, Ieval) ->
@@ -1152,13 +968,13 @@ eval_lc1(E, [{guard,Q}|Qs], Bs0, Ieval) ->
false -> []
end;
eval_lc1(E, [Q|Qs], Bs0, Ieval) ->
- case expr(Q, Bs0, Ieval#ieval{last_call=false}) of
+ case expr(Q, Bs0, Ieval#ieval{top=false}) of
{value,true,Bs} -> eval_lc1(E, Qs, Bs, Ieval);
{value,false,_Bs} -> [];
{value,V,Bs} -> exception(error, {bad_filter,V}, Bs, Ieval)
end;
eval_lc1(E, [], Bs, Ieval) ->
- {value,V,_} = expr(E, Bs, Ieval#ieval{last_call=false}),
+ {value,V,_} = expr(E, Bs, Ieval#ieval{top=false}),
[V].
%% eval_bc(Expr,[Qualifier],Bindings,IevalState) ->
@@ -1171,12 +987,12 @@ eval_bc(E, Qs, Bs, Ieval) ->
eval_bc1(E, [{generate,Line,P,L0}|Qs], Bs0, Ieval0) ->
Ieval = Ieval0#ieval{line=Line},
- {value,L1,Bs1} = expr(L0, Bs0, Ieval#ieval{last_call=false}),
+ {value,L1,Bs1} = expr(L0, Bs0, Ieval#ieval{top=false}),
CompFun = fun(NewBs) -> eval_bc1(E, Qs, NewBs, Ieval) end,
eval_generate(L1, P, Bs1, CompFun, Ieval);
eval_bc1(E, [{b_generate,Line,P,L0}|Qs], Bs0, Ieval0) ->
Ieval = Ieval0#ieval{line=Line},
- {value,Bin,_} = expr(L0, Bs0, Ieval#ieval{last_call=false}),
+ {value,Bin,_} = expr(L0, Bs0, Ieval#ieval{top=false}),
CompFun = fun(NewBs) -> eval_bc1(E, Qs, NewBs, Ieval) end,
eval_b_generate(Bin, P, Bs0, CompFun, Ieval);
eval_bc1(E, [{guard,Q}|Qs], Bs0, Ieval) ->
@@ -1185,13 +1001,13 @@ eval_bc1(E, [{guard,Q}|Qs], Bs0, Ieval) ->
false -> []
end;
eval_bc1(E, [Q|Qs], Bs0, Ieval) ->
- case expr(Q, Bs0, Ieval#ieval{last_call=false}) of
+ case expr(Q, Bs0, Ieval#ieval{top=false}) of
{value,true,Bs} -> eval_bc1(E, Qs, Bs, Ieval);
{value,false,_Bs} -> [];
{value,V,Bs} -> exception(error, {bad_filter,V}, Bs, Ieval)
end;
eval_bc1(E, [], Bs, Ieval) ->
- {value,V,_} = expr(E, Bs, Ieval#ieval{last_call=false}),
+ {value,V,_} = expr(E, Bs, Ieval#ieval{top=false}),
[V].
eval_generate([V|Rest], P, Bs0, CompFun, Ieval) ->
@@ -1208,7 +1024,7 @@ eval_generate(Term, _P, Bs, _CompFun, Ieval) ->
exception(error, {bad_generator,Term}, Bs, Ieval).
eval_b_generate(<<_/bitstring>>=Bin, P, Bs0, CompFun, Ieval) ->
- Mfun = fun(L, R, Bs) -> match1(L, R, Bs, Bs0) end,
+ Mfun = match_fun(Bs0),
Efun = fun(Exp, Bs) -> expr(Exp, Bs, #ieval{}) end,
case eval_bits:bin_gen(P, Bin, erl_eval:new_bindings(), Bs0, Mfun, Efun) of
{match,Rest,Bs1} ->
@@ -1222,24 +1038,13 @@ eval_b_generate(<<_/bitstring>>=Bin, P, Bs0, CompFun, Ieval) ->
eval_b_generate(Term, _P, Bs, _CompFun, Ieval) ->
exception(error, {bad_generator,Term}, Bs, Ieval).
-module_info(Mod, module) -> Mod;
-module_info(_Mod, compile) -> [];
-module_info(Mod, attributes) ->
- {ok, Attr} = dbg_iserver:call(get(int), {lookup, Mod, attributes}),
- Attr;
-module_info(_Mod, imports) -> [];
-module_info(Mod, exports) ->
- {ok, Exp} = dbg_iserver:call(get(int), {lookup, Mod, exports}),
- Exp;
-module_info(_Mod, functions) -> [].
-
safe_bif(M, F, As, Bs, Ieval) ->
try apply(M, F, As) of
Value ->
{value,Value,Bs}
catch
Class:Reason ->
- exception(Class, Reason, Bs, Ieval)
+ exception(Class, Reason, Bs, Ieval, true)
end.
eval_send(To, Msg, Bs, Ieval) ->
@@ -1408,12 +1213,12 @@ flush_traces(Debugged) ->
%% eval_list(ExpressionList, Bindings, Ieval)
%% Evaluate a list of expressions "in parallel" at the same level.
eval_list(Es, Bs, Ieval) ->
- eval_list(Es, [], Bs, Bs, Ieval).
+ eval_list_1(Es, [], Bs, Bs, Ieval#ieval{top=false}).
-eval_list([E|Es], Vs, BsOrig, Bs0, Ieval) ->
- {value,V,Bs1} = expr(E, BsOrig, Ieval#ieval{last_call=false}),
- eval_list(Es, [V|Vs], BsOrig, merge_bindings(Bs1,Bs0,Ieval), Ieval);
-eval_list([], Vs, _, Bs, _Ieval) ->
+eval_list_1([E|Es], Vs, BsOrig, Bs0, Ieval) ->
+ {value,V,Bs1} = expr(E, BsOrig, Ieval),
+ eval_list_1(Es, [V|Vs], BsOrig, merge_bindings(Bs1, Bs0, Ieval), Ieval);
+eval_list_1([], Vs, _, Bs, _Ieval) ->
{lists:reverse(Vs,[]),Bs}.
%% if_clauses(Clauses, Bindings, Ieval)
@@ -1453,7 +1258,7 @@ catch_clauses(Exception, [{clause,_,[P],G,B}|CatchCs], Bs0, Ieval) ->
true ->
%% Exception caught, reset exit info
put(exit_info, undefined),
- pop(Ieval#ieval.level),
+ dbg_istk:pop(Ieval#ieval.level),
seq(B, Bs, Ieval);
false ->
catch_clauses(Exception, CatchCs, Bs0, Ieval)
@@ -1588,11 +1393,9 @@ match1({cons,_,H,T}, [H1|T1], Bs0, BBs) ->
match1({tuple,_,Elts}, Tuple, Bs, BBs)
when length(Elts) =:= tuple_size(Tuple) ->
match_tuple(Elts, Tuple, 1, Bs, BBs);
-match1({bin,_,Fs}, B, Bs0, BBs0) when is_bitstring(B) ->
- Bs1 = lists:sort(Bs0), %Kludge.
- BBs = lists:sort(BBs0),
- try eval_bits:match_bits(Fs, B, Bs1, BBs,
- fun(L, R, Bs) -> match1(L, R, Bs, BBs) end,
+match1({bin,_,Fs}, B, Bs0, BBs) when is_bitstring(B) ->
+ try eval_bits:match_bits(Fs, B, Bs0, BBs,
+ match_fun(BBs),
fun(E, Bs) -> expr(E, Bs, #ieval{}) end,
false)
catch
@@ -1601,6 +1404,12 @@ match1({bin,_,Fs}, B, Bs0, BBs0) when is_bitstring(B) ->
match1(_,_,_,_) ->
throw(nomatch).
+match_fun(BBs) ->
+ fun(match, {L,R,Bs}) -> match1(L, R, Bs, BBs);
+ (binding, {Name,Bs}) -> binding(Name, Bs);
+ (add_binding, {Name,Val,Bs}) -> add_binding(Name, Val, Bs)
+ end.
+
match_tuple([E|Es], Tuple, I, Bs0, BBs) ->
{match,Bs} = match1(E, element(I, Tuple), Bs0, BBs),
match_tuple(Es, Tuple, I+1, Bs, BBs);
@@ -1731,3 +1540,19 @@ add_binding(N,Val,[B1|Bs]) ->
[B1|add_binding(N,Val,Bs)];
add_binding(N,Val,[]) ->
[{N,Val}].
+
+%% get_stacktrace() -> Stacktrace
+%% Return the latest stacktrace for the process.
+get_stacktrace() ->
+ case get(stacktrace) of
+ MakeStk when is_function(MakeStk, 1) ->
+ %% The stacktrace has not been constructed before.
+ %% Construct it and remember the result.
+ Depth = erlang:system_flag(backtrace_depth, 8),
+ erlang:system_flag(backtrace_depth, Depth),
+ Stk = MakeStk(Depth),
+ put(stacktrace, Stk),
+ Stk;
+ Stk when is_list(Stk) ->
+ Stk
+ end.