From 93f5844185a459cbf9efc3843919c463a2eef0fe Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= Date: Thu, 8 Oct 2015 13:04:40 +0200 Subject: Teach erlang:is_builtin/3 that erlang:apply/3 is built-in erlang:is_builtin(erlang, apply, 3) returns 'false'. That seems to be an oversight in the implementation of erlang:is_builtin/3 rather than a conscious design decision. Part of apply/3 is implemented in C (as a special instruction), and part of it in Erlang (only used if apply/3 is used recursively). That makes apply/3 special compared to all other BIFs. From the viewpoint of the user, apply/3 is a built-in function, since it cannot possibly be implemented in pure Erlang. Noticed-by: Stavros Aronis --- erts/emulator/beam/beam_emu.c | 9 +++++++++ erts/emulator/test/bif_SUITE.erl | 21 +++++++++++++++++++-- lib/tools/test/xref_SUITE.erl | 28 +++++++++++++--------------- 3 files changed, 41 insertions(+), 17 deletions(-) diff --git a/erts/emulator/beam/beam_emu.c b/erts/emulator/beam/beam_emu.c index a42ce1c9f1..faf496a030 100644 --- a/erts/emulator/beam/beam_emu.c +++ b/erts/emulator/beam/beam_emu.c @@ -6752,6 +6752,15 @@ erts_is_builtin(Eterm Mod, Eterm Name, int arity) Export e; Export* ep; + if (Mod == am_erlang && Name == am_apply && arity == 3) { + /* + * Special case. apply/3 is built-in (implemented in C), + * but implemented in a different way than all other + * BIFs. + */ + return 1; + } + e.code[0] = Mod; e.code[1] = Name; e.code[2] = arity; diff --git a/erts/emulator/test/bif_SUITE.erl b/erts/emulator/test/bif_SUITE.erl index d6a771e7b9..ebc4db53c4 100644 --- a/erts/emulator/test/bif_SUITE.erl +++ b/erts/emulator/test/bif_SUITE.erl @@ -32,7 +32,8 @@ specs/1,improper_bif_stubs/1,auto_imports/1, t_list_to_existing_atom/1,os_env/1,otp_7526/1, binary_to_atom/1,binary_to_existing_atom/1, - atom_to_binary/1,min_max/1, erlang_halt/1]). + atom_to_binary/1,min_max/1, erlang_halt/1, + is_builtin/1]). suite() -> [{ct_hooks,[ts_install_cth]}]. @@ -42,7 +43,7 @@ all() -> t_list_to_existing_atom, os_env, otp_7526, display, atom_to_binary, binary_to_atom, binary_to_existing_atom, - min_max, erlang_halt]. + min_max, erlang_halt, is_builtin]. groups() -> []. @@ -716,6 +717,22 @@ wait_until_stable_size(File,PrevSz) -> wait_until_stable_size(File,NewSz) end. +is_builtin(_Config) -> + Exp0 = [{M,F,A} || {M,_} <- code:all_loaded(), + {F,A} <- M:module_info(exports)], + Exp = ordsets:from_list(Exp0), + + %% erlang:apply/3 is considered to be built-in, but is not + %% implemented as other BIFs. + + Builtins0 = [{erlang,apply,3}|erlang:system_info(snifs)], + Builtins = ordsets:from_list(Builtins0), + NotBuiltin = ordsets:subtract(Exp, Builtins), + _ = [true = erlang:is_builtin(M, F, A) || {M,F,A} <- Builtins], + _ = [false = erlang:is_builtin(M, F, A) || {M,F,A} <- NotBuiltin], + + ok. + %% Helpers diff --git a/lib/tools/test/xref_SUITE.erl b/lib/tools/test/xref_SUITE.erl index ad47b31443..71c8b1a277 100644 --- a/lib/tools/test/xref_SUITE.erl +++ b/lib/tools/test/xref_SUITE.erl @@ -1151,17 +1151,13 @@ read_expected(Version) -> {POS8+4,{FF,{a,b,1}}}, {POS8+4,{FF,{erlang,apply,2}}}, {POS8+5,{FF,{erlang,apply,2}}}, - {POS8+6,{FF,{erlang,apply,3}}}, {POS8+6,{FF,{m,f,1}}}, - {POS8+7,{FF,{erlang,apply,3}}}, - {POS9+1,{FF,{erlang,apply,3}}}, {POS9+1,{FF,{read,bi,0}}}, {POS9+2,{FF,{a,b,1}}}, {POS9+2,{FF,{erlang,apply,2}}}, {POS9+3,{FF,{erlang,apply,2}}}, {POS9+4,{FF,{erlang,apply,2}}}, {POS9+4,{FF,{erlang,not_a_function,1}}}, - {POS9+5,{FF,{erlang,apply,3}}}, {POS9+5,{FF,{mod,func,2}}}, {POS9+6,{FF,{erlang,apply,1}}}, {POS9+7,{FF,{erlang,apply,2}}}, @@ -1169,17 +1165,11 @@ read_expected(Version) -> {POS9+8,{FF,{q,f,1}}}, {POS10+4,{FF,{erlang,apply,2}}}, {POS10+5,{FF,{mod1,fun1,1}}}, - {POS11+1,{FF,{erlang,apply,3}}}, - {POS11+2,{FF,{erlang,apply,3}}}, - {POS11+3,{FF,{erlang,apply,3}}}, - {POS11+4,{FF,{erlang,apply,3}}}, {POS11+6,{FF,{erlang,apply,2}}}, {POS12+1,{FF,{erlang,apply,2}}}, {POS12+4,{FF,{erlang,apply,2}}}, - {POS12+5,{FF,{erlang,apply,3}}}, {POS12+5,{FF,{m3,f3,2}}}, {POS12+7,{FF,{erlang,apply,2}}}, - {POS12+8,{FF,{erlang,apply,3}}}, {POS13+1,{FF,{dm,df,1}}}, {POS13+6,{{read,bi,0},{foo,module_info,0}}}, {POS13+7,{{read,bi,0},{read,module_info,0}}}, @@ -1189,10 +1179,6 @@ read_expected(Version) -> OK = case Version of abstract_v1 -> - [{POS8+3, {FF,{erlang,apply,3}}}, - {POS10+1, {FF,{erlang,apply,3}}}, - {POS10+6, {FF,{erlang,apply,3}}}] - ++ [{0,{FF,{read,'$F_EXPR',178}}}, {0,{FF,{modul,'$F_EXPR',179}}}] ++ O1; @@ -1213,13 +1199,25 @@ read_expected(Version) -> {POS3+3, {FF,{erlang,spawn_link,3}}}, {POS3+4, {FF,{erlang,spawn_link,3}}}, {POS6+4, {FF,{erlang,spawn,3}}}, + {POS8+6,{FF,{erlang,apply,3}}}, + {POS8+7,{FF,{erlang,apply,3}}}, + {POS9+1,{FF,{erlang,apply,3}}}, + {POS9+5,{FF,{erlang,apply,3}}}, + {POS11+1,{FF,{erlang,apply,3}}}, + {POS11+2,{FF,{erlang,apply,3}}}, + {POS11+3,{FF,{erlang,apply,3}}}, + {POS11+4,{FF,{erlang,apply,3}}}, + {POS12+5,{FF,{erlang,apply,3}}}, + {POS12+8,{FF,{erlang,apply,3}}}, {POS13+5, {{read,bi,0},{erlang,length,1}}}, {POS14+3, {{read,bi,0},{erlang,length,1}}}], %% Operators (OTP-8647): OKB = case Version of abstract_v1 -> - []; + [{POS8+3, {FF,{erlang,apply,3}}}, + {POS10+1, {FF,{erlang,apply,3}}}, + {POS10+6, {FF,{erlang,apply,3}}}]; _ -> [{POS13+16, {{read,bi,0},{erlang,'!',2}}}, {POS13+16, {{read,bi,0},{erlang,'-',1}}}, -- cgit v1.2.3