diff options
Diffstat (limited to 'lib/compiler')
| -rw-r--r-- | lib/compiler/src/beam_bsm.erl | 1 | ||||
| -rw-r--r-- | lib/compiler/src/beam_validator.erl | 1 | ||||
| -rw-r--r-- | lib/compiler/src/sys_core_fold.erl | 25 | ||||
| -rw-r--r-- | lib/compiler/test/bs_match_SUITE.erl | 15 | ||||
| -rw-r--r-- | lib/compiler/test/core_fold_SUITE.erl | 36 |
5 files changed, 70 insertions, 8 deletions
diff --git a/lib/compiler/src/beam_bsm.erl b/lib/compiler/src/beam_bsm.erl index fdfcb08125..d54c2a9fde 100644 --- a/lib/compiler/src/beam_bsm.erl +++ b/lib/compiler/src/beam_bsm.erl @@ -209,6 +209,7 @@ btb_reaches_match_2([{call,Arity,{f,Lbl}}|Is], Regs, D) -> btb_reaches_match_2([{apply,Arity}|Is], Regs, D) -> btb_call(Arity+2, apply, Regs, Is, D); btb_reaches_match_2([{call_fun,Live}=I|Is], Regs, D) -> + btb_ensure_not_used([{x,Live}], I, Regs), btb_call(Live, I, Regs, Is, D); btb_reaches_match_2([{make_fun2,_,_,_,Live}|Is], Regs, D) -> btb_call(Live, make_fun2, Regs, Is, D); diff --git a/lib/compiler/src/beam_validator.erl b/lib/compiler/src/beam_validator.erl index 97f84da08f..682f7adbc2 100644 --- a/lib/compiler/src/beam_validator.erl +++ b/lib/compiler/src/beam_validator.erl @@ -574,6 +574,7 @@ valfun_4({apply,Live}, Vst) -> valfun_4({apply_last,Live,_}, Vst) -> tail_call(apply, Live+2, Vst); valfun_4({call_fun,Live}, Vst) -> + validate_src([{x,Live}], Vst), call('fun', Live+1, Vst); valfun_4({call,Live,Func}, Vst) -> call(Func, Live, Vst); diff --git a/lib/compiler/src/sys_core_fold.erl b/lib/compiler/src/sys_core_fold.erl index 9ce6bb48bf..e302e2324d 100644 --- a/lib/compiler/src/sys_core_fold.erl +++ b/lib/compiler/src/sys_core_fold.erl @@ -1945,9 +1945,30 @@ eval_case(#c_case{arg=E,clauses=[#c_clause{pats=Ps0,body=B}]}, Sub) -> true -> cerl:values_es(E); false -> [E] end, - {true,Bs} = cerl_clauses:match_list(Ps0, Es), + %% Consider: + %% + %% case SomeSideEffect() of + %% X=Y -> ... + %% end + %% + %% We must not rewrite it to: + %% + %% let <X,Y> = <SomeSideEffect(),SomeSideEffect()> in ... + %% + %% because SomeSideEffect() would be called evaluated twice. + %% + %% Instead we must evaluate the case expression in an outer let + %% like this: + %% + %% let NewVar = SomeSideEffect() in + %% let <X,Y> = <NewVar,NewVar> in ... + %% + Vs = make_vars([], length(Es)), + {true,Bs} = cerl_clauses:match_list(Ps0, Vs), {Ps,As} = unzip(Bs), - expr(#c_let{vars=Ps,arg=core_lib:make_values(As),body=B}, sub_new(Sub)); + InnerLet = cerl:c_let(Ps, core_lib:make_values(As), B), + Let = cerl:c_let(Vs, E, InnerLet), + expr(Let, sub_new(Sub)); eval_case(Case, _) -> Case. %% case_opt(CaseArg, [Clause]) -> {CaseArg,[Clause]}. diff --git a/lib/compiler/test/bs_match_SUITE.erl b/lib/compiler/test/bs_match_SUITE.erl index 9f15845d33..149b9bbb8f 100644 --- a/lib/compiler/test/bs_match_SUITE.erl +++ b/lib/compiler/test/bs_match_SUITE.erl @@ -34,7 +34,7 @@ otp_7188/1,otp_7233/1,otp_7240/1,otp_7498/1, match_string/1,zero_width/1,bad_size/1,haystack/1, cover_beam_bool/1,matched_out_size/1,follow_fail_branch/1, - no_partition/1]). + no_partition/1,calling_a_binary/1]). -export([coverage_id/1,coverage_external_ignore/2]). @@ -59,7 +59,7 @@ groups() -> matching_and_andalso,otp_7188,otp_7233,otp_7240, otp_7498,match_string,zero_width,bad_size,haystack, cover_beam_bool,matched_out_size,follow_fail_branch, - no_partition]}]. + no_partition,calling_a_binary]}]. init_per_suite(Config) -> @@ -1178,6 +1178,17 @@ no_partition_2([], a5) -> no_partition_2(42.0, a6) -> six. +calling_a_binary(Config) when is_list(Config) -> + [] = call_binary(<<>>, []), + {'EXIT',{badarg,_}} = (catch call_binary(<<1>>, [])), + {'EXIT',{badarg,_}} = (catch call_binary(<<1,2,3>>, [])), + ok. + +call_binary(<<>>, Acc) -> + Acc; +call_binary(<<H,T/bits>>, Acc) -> + T(<<Acc/binary,H>>). + check(F, R) -> R = F(). diff --git a/lib/compiler/test/core_fold_SUITE.erl b/lib/compiler/test/core_fold_SUITE.erl index 69f61a046f..8151dc1b16 100644 --- a/lib/compiler/test/core_fold_SUITE.erl +++ b/lib/compiler/test/core_fold_SUITE.erl @@ -22,7 +22,8 @@ init_per_group/2,end_per_group/2, t_element/1,setelement/1,t_length/1,append/1,t_apply/1,bifs/1, eq/1,nested_call_in_case/1,guard_try_catch/1,coverage/1, - unused_multiple_values_error/1,unused_multiple_values/1]). + unused_multiple_values_error/1,unused_multiple_values/1, + multiple_aliases/1]). -export([foo/0,foo/1,foo/2,foo/3]). @@ -38,7 +39,8 @@ groups() -> [{p,test_lib:parallel(), [t_element,setelement,t_length,append,t_apply,bifs, eq,nested_call_in_case,guard_try_catch,coverage, - unused_multiple_values_error,unused_multiple_values]}]. + unused_multiple_values_error,unused_multiple_values, + multiple_aliases]}]. init_per_suite(Config) -> @@ -299,8 +301,6 @@ cover_is_safe_bool_expr(X) -> bsm_an_inlined(<<_:8>>, _) -> ok; bsm_an_inlined(_, _) -> error. -id(I) -> I. - unused_multiple_values_error(Config) when is_list(Config) -> PrivDir = ?config(priv_dir, Config), Dir = filename:dirname(code:which(?MODULE)), @@ -338,3 +338,31 @@ do_something(I) -> put(unused_multiple_values, [I|get(unused_multiple_values)]), I. + + +%% Make sure that multiple aliases does not cause +%% the case expression to be evaluated twice. +multiple_aliases(Config) when is_list(Config) -> + do_ma(fun() -> + X = Y = run_once(), + {X,Y} + end, {ok,ok}), + do_ma(fun() -> + case {true,run_once()} of + {true=A=B,ok=X=Y} -> + {A,B,X,Y} + end + end, {true,true,ok,ok}), + ok. + +do_ma(Fun, Expected) when is_function(Fun, 0) -> + Expected = Fun(), + ran_once = erase(run_once), + ok. + +run_once() -> + undefined = put(run_once, ran_once), + ok. + + +id(I) -> I. |