%%% -*- erlang-indent-level: 2 -*-
%%%-------------------------------------------------------------------
%%% Author: Kostis Sagonas
%%%
%%% Contains code examples that exhibited crashes in the HiPE compiler.
%%%-------------------------------------------------------------------
-module(basic_issues_hipe).
-export([test/0]).
%% functions that need to be exported so that they are retained.
-export([auth/4]).
test() ->
ok = test_dominance_trees(),
ok = test_merged_const(),
ok = test_var_pair(),
ok = test_bif_fails(),
ok = test_find_catches(),
ok = test_heap_allocate_trim(),
ok.
%%--------------------------------------------------------------------
%% This is taken from a file sent to us by Martin Bjorklund @ Nortel
%% on 14th November 2004. The problem was in the SSA unconvert pass.
%%
%% No tests here; we simply check that the HiPE compiler does not go
%% into an infinite loop when compiling strange functions like this.
%%--------------------------------------------------------------------
auth(_, A, B, C) ->
auth(A, B, C, []).
%%--------------------------------------------------------------------
%% Exposed a crash in the generation of dominance trees used in SSA.
%%--------------------------------------------------------------------
-record(state, {f}).
test_dominance_trees() ->
{ok, true} = doit(true, #state{f = true}),
ok.
doit(Foo, S) ->
Fee = case Foo of
Bar when Bar == S#state.f; Bar == [] -> true;
_ -> false
end,
{ok, Fee}.
%%--------------------------------------------------------------------
%% Checks that the merging of constants in the constant table uses the
%% appropriate comparison function for this.
%%--------------------------------------------------------------------
test_merged_const() ->
Const1 = {'', 1.0000},
Const2 = {'', 1},
match(Const1, Const2).
match(A, A) ->
error;
match(_A, _B) ->
ok.
%%--------------------------------------------------------------------
%% Checks that the HiPE compiler does not get confused by constant
%% data structures similar to the internal compiler data structures.
%%--------------------------------------------------------------------
test_var_pair() ->
ok = var_pair([gazonk]).
var_pair([_|_]) ->
var_pair({var, some_atom});
var_pair(_) ->
ok.
%%--------------------------------------------------------------------
%% This module was causing the HiPE compiler to crash in January 2007.
%% The culprit was an "optimization" of the BEAM compiler: postponing
%% the save of x variables when BIFs cannot fail. This was fixed on
%% February 1st, by making the HiPE compiler use the same functions
%% as the BEAM compiler for deciding whether a BIF fails.
%%--------------------------------------------------------------------
test_bif_fails() ->
[42] = bif_fails_in_catch([42]),
true = bif_fails_in_try([42]),
ok.
bif_fails_in_catch(X) ->
case catch get(gazonk) of
_ -> X
end.
bif_fails_in_try(X) ->
try
true = X =/= []
catch
_ -> nil(X)
end.
nil(_) -> [].
%%--------------------------------------------------------------------
%% Test that resulted in a native code compiler crash in the code of
%% hipe_icode_exceptions:find_catches/1 when compiling find_catches/2.
%%--------------------------------------------------------------------
test_find_catches() ->
42 = find_catches(a, false),
ok.
find_catches(X, Y) ->
case X of
a when Y =:= true ->
catch id(X),
X;
b when Y =:= true ->
catch id(X),
X;
a ->
catch id(X),
42;
b ->
catch id(X),
42
end.
id(X) -> X.
%%--------------------------------------------------------------------
%% Date: Dec 28, 2007
%%
%% This is a test adapted from the file sent to the Erlang mailing
%% list by Eranga Udesh. The file did not compile because of problems
%% with the heap_allocate instruction and stack trimming.
%%--------------------------------------------------------------------
test_heap_allocate_trim() ->
{abandon, 42} = get_next_retry(a, 42),
ok.
get_next_retry(Error, Count) ->
case catch pair(retry_scheme, {Error, Count}) of
_ ->
case pair(Error, Count) of
_ -> {abandon, Count}
end
end.
pair(A, B) -> {A, B}.
