diff options
Diffstat (limited to 'lib/compiler/test/beam_ssa_SUITE.erl')
| -rw-r--r-- | lib/compiler/test/beam_ssa_SUITE.erl | 152 |
1 files changed, 148 insertions, 4 deletions
diff --git a/lib/compiler/test/beam_ssa_SUITE.erl b/lib/compiler/test/beam_ssa_SUITE.erl index 15cf9bcbf3..3b510f3528 100644 --- a/lib/compiler/test/beam_ssa_SUITE.erl +++ b/lib/compiler/test/beam_ssa_SUITE.erl @@ -22,7 +22,8 @@ -export([all/0,suite/0,groups/0,init_per_suite/1,end_per_suite/1, init_per_group/2,end_per_group/2, calls/1,tuple_matching/1,recv/1,maps/1, - cover_ssa_dead/1,combine_sw/1,share_opt/1]). + cover_ssa_dead/1,combine_sw/1,share_opt/1, + beam_ssa_dead_crash/1,stack_init/1]). suite() -> [{ct_hooks,[ts_install_cth]}]. @@ -37,7 +38,9 @@ groups() -> maps, cover_ssa_dead, combine_sw, - share_opt + share_opt, + beam_ssa_dead_crash, + stack_init ]}]. init_per_suite(Config) -> @@ -188,6 +191,15 @@ recv(_Config) -> self() ! {[self(),r1],{2,99,<<"data">>}}, {Parent,r1,<<1:32,2:8,99:8,"data">>} = tricky_recv_4(), + %% Test tricky_recv_5/0. + self() ! 1, + a = tricky_recv_5(), + self() ! 2, + b = tricky_recv_5(), + + %% tricky_recv_6/0 is a compile-time error. + tricky_recv_6(), + ok. sync_wait_mon({Pid, Ref}, Timeout) -> @@ -293,6 +305,38 @@ tricky_recv_4() -> end, id({Pid,R,Request}). +%% beam_ssa_pre_codegen would accidentally create phi nodes on critical edges +%% when fixing up receives; the call to id/2 can either succeed or land in the +%% catch block, and we added a phi node to its immediate successor. +tricky_recv_5() -> + try + receive + X=1 -> + id(42), + a; + X=2 -> + b + end, + case X of + 1 -> a; + 2 -> b + end + catch + _:_ -> c + end. + +%% When fixing tricky_recv_5, we introduced a compiler crash when the common +%% exit block was ?BADARG_BLOCK and floats were in the picture. +tricky_recv_6() -> + RefA = make_ref(), + RefB = make_ref(), + receive + {RefA, Number} -> Number + 1.0; + {RefB, Number} -> Number + 2.0 + after 0 -> + ok + end. + maps(_Config) -> {'EXIT',{{badmatch,#{}},_}} = (catch maps_1(any)), ok. @@ -481,9 +525,11 @@ do_comb_sw_2(X) -> erase(?MODULE). share_opt(_Config) -> - ok = do_share_opt(0). + ok = do_share_opt_1(0), + ok = do_share_opt_2(), + ok. -do_share_opt(A) -> +do_share_opt_1(A) -> %% The compiler would be stuck in an infinite loop in beam_ssa_share. case A of 0 -> a; @@ -492,6 +538,104 @@ do_share_opt(A) -> end, receive after 1 -> ok end. +do_share_opt_2() -> + ok = sopt_2({[pointtopoint], [{dstaddr,any}]}, ok), + ok = sopt_2({[broadcast], [{broadaddr,any}]}, ok), + ok = sopt_2({[], []}, ok), + ok. + +sopt_2({Flags, Opts}, ok) -> + Broadcast = lists:member(broadcast, Flags), + P2P = lists:member(pointtopoint, Flags), + case Opts of + %% The following two clauses would be combined to one, silently + %% discarding the guard test of the P2P variable. + [{broadaddr,_}|Os] when Broadcast -> + sopt_2({Flags, Os}, ok); + [{dstaddr,_}|Os] when P2P -> + sopt_2({Flags, Os}, ok); + [] -> + ok + end. + +beam_ssa_dead_crash(_Config) -> + not_A_B = do_beam_ssa_dead_crash(id(false), id(true)), + not_A_not_B = do_beam_ssa_dead_crash(false, false), + neither = do_beam_ssa_dead_crash(true, false), + neither = do_beam_ssa_dead_crash(true, true), + ok. + +do_beam_ssa_dead_crash(A, B) -> + %% beam_ssa_dead attempts to shortcut branches that branch other + %% branches. When a two-way branch is encountered, beam_ssa_dead + %% will simulate execution along both paths, in the hope that both + %% paths happens to end up in the same place. + %% + %% During the simulated execution of this function, the boolean + %% varible for a `br` instruction would be replaced with the + %% literal atom `nil`, which is not allowed, and would crash the + %% compiler. In practice, during the actual execution, control + %% would never be transferred to that `br` instruction when the + %% variable in question had the value `nil`. + %% + %% beam_ssa_dead has been updated to immediately abort the search + %% along the current path if there is an attempt to substitute a + %% non-boolean value into a `br` instruction. + + case + case not A of + false -> + false; + true -> + B + end + of + V + when + V /= nil + andalso + V /= false -> + not_A_B; + _ -> + case + case not A of + false -> + false; + true -> + not B + end + of + true -> + not_A_not_B; + false -> + neither + end + end. + +stack_init(_Config) -> + 6 = stack_init(a, #{a => [1,2,3]}), + 0 = stack_init(missing, #{}), + ok. + +stack_init(Key, Map) -> + %% beam_ssa_codegen would wrongly assume that y(0) would always be + %% initialized by the `get_map_elements` instruction that follows, and + %% would set up the stack frame using an `allocate` instruction and + %% would not generate an `init` instruction to initialize y(0). + Res = case Map of + #{Key := Elements} -> + %% Elements will be assigned to y(0) if the key Key exists. + lists:foldl(fun(El, Acc) -> + Acc + El + end, 0, Elements); + #{} -> + %% y(0) will be left uninitialized when the key is not + %% present in the map. + 0 + end, + %% y(0) would be uninitialized here if the key was not present in the map + %% (if the second clause was executed). + id(Res). %% The identity function. id(I) -> I. |