%% -*- erlang-indent-level: 2 -*-
%%
%% 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.
%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% Copyright (c) 2001 by Erik Johansson. All Rights Reserved
%% ====================================================================
%% Filename : hipe_rtl_exceptions.erl
%% Module : hipe_rtl_exceptions
%% Purpose :
%% Notes :
%% History : * 2001-04-10 Erik Johansson ([email protected]):
%% Created.
%% ====================================================================
%% Exports :
%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-module(hipe_rtl_exceptions).
-export([gen_fail/3, gen_begin_handler/3]).
-include("../main/hipe.hrl").
-include("hipe_literals.hrl").
%% --------------------------------------------------------------------
%% Handle the Icode instruction
%% FAIL
%%
gen_fail(Class, Args, L) ->
case Args of
[Reason] ->
case Class of
exit ->
gen_exit(Reason, L);
throw ->
gen_throw(Reason, L);
error ->
gen_error(Reason, L)
end;
[Arg1,Arg2] ->
case Class of
error ->
Reason = Arg1, ArgList = Arg2,
gen_error(Reason, ArgList, L);
rethrow ->
Exception = Arg1, Reason = Arg2,
gen_rethrow(Exception, Reason, L)
end
end.
%% --------------------------------------------------------------------
%% Exception handler glue; interfaces between the runtime system's
%% exception state and the Icode view of exception handling.
gen_begin_handler(I, VarMap, ConstTab) ->
Ds = hipe_icode:begin_handler_dstlist(I),
{Vars, VarMap1} = hipe_rtl_varmap:ivs2rvs(Ds, VarMap),
[FTagVar,FValueVar,FTraceVar] = Vars,
{[hipe_rtl:mk_comment('begin_handler'),
hipe_rtl_arch:pcb_load(FValueVar, ?P_FVALUE),
hipe_rtl_arch:pcb_load(FTraceVar, ?P_FTRACE),
%% synthesized from P->freason by hipe_handle_exception()
hipe_rtl_arch:pcb_load(FTagVar, ?P_ARG0)
],
VarMap1, ConstTab}.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%
%% Exceptions
gen_exit(Reason, L) ->
gen_fail_call({erlang,exit,1}, [Reason], L).
gen_throw(Reason, L) ->
gen_fail_call({erlang,throw,1}, [Reason], L).
gen_error(Reason, L) ->
gen_fail_call({erlang,error,1}, [Reason], L).
gen_error(Reason, ArgList, L) ->
gen_fail_call({erlang,error,2}, [Reason,ArgList], L).
gen_rethrow(Exception, Reason, L) ->
gen_fail_call(rethrow, [Exception,Reason], L).
%% Generic fail. We can't use 'enter' with a fail label (there can be no
%% stack descriptor info for an enter), so for a non-nil fail label we
%% generate a call followed by a dummy return.
%%
%% Update: The runtime system now interprets the return address of
%% the BIF call in order to list the invoking MFA in the stack trace.
%% Generating tailcalls here defeats that purpose, so we no longer do that.
%%gen_fail_call(Fun, Args, []) ->
%% [hipe_rtl:mk_enter(Fun, Args, remote)];
gen_fail_call(Fun, Args, L) ->
ContLbl = hipe_rtl:mk_new_label(),
Cont = hipe_rtl:label_name(ContLbl),
Zero = hipe_rtl:mk_imm(hipe_tagscheme:mk_fixnum(0)),
[hipe_rtl:mk_call([], Fun, Args, Cont, L, remote),
ContLbl,
hipe_rtl:mk_return([Zero])].
