From bf84118febaae7857f12625584f33a649f79aeed Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= Date: Mon, 23 Apr 2018 15:20:43 +0200 Subject: Rewrite a call of a literal external fun to a direct call Rewrite calls such as: (fun erlang:abs/1)(-42) to: erlang:abs(-42) While we are at it, also add rewriting of apply/2 with a fixed number of arguments to a direct call of the fun. For example: apply(F, [A,B]) would be rewritten to: F(A, B) https://bugs.erlang.org/browse/ERL-614 --- lib/compiler/src/sys_core_fold.erl | 66 +++++++++++++++++++++++++++++--------- 1 file changed, 51 insertions(+), 15 deletions(-) (limited to 'lib/compiler/src') diff --git a/lib/compiler/src/sys_core_fold.erl b/lib/compiler/src/sys_core_fold.erl index bb3a9c7628..5fd407b228 100644 --- a/lib/compiler/src/sys_core_fold.erl +++ b/lib/compiler/src/sys_core_fold.erl @@ -401,14 +401,15 @@ expr(#c_receive{clauses=Cs0,timeout=T0,action=A0}=Recv, Ctxt, Sub) -> T1 = expr(T0, value, Sub), A1 = body(A0, Ctxt, Sub), Recv#c_receive{clauses=Cs1,timeout=T1,action=A1}; -expr(#c_apply{anno=Anno,op=Op0,args=As0}=App, _, Sub) -> +expr(#c_apply{anno=Anno,op=Op0,args=As0}=Apply0, _, Sub) -> Op1 = expr(Op0, value, Sub), As1 = expr_list(As0, value, Sub), case cerl:is_data(Op1) andalso not is_literal_fun(Op1) of false -> - App#c_apply{op=Op1,args=As1}; + Apply = Apply0#c_apply{op=Op1,args=As1}, + fold_apply(Apply, Op1, As1); true -> - add_warning(App, invalid_call), + add_warning(Apply0, invalid_call), Err = #c_call{anno=Anno, module=#c_literal{val=erlang}, name=#c_literal{val=error}, @@ -766,6 +767,25 @@ make_effect_seq([H|T], Sub) -> end; make_effect_seq([], _) -> void(). +%% fold_apply(Apply, LiteraFun, Args) -> Apply. +%% Replace an apply of a literal external fun with a call. + +fold_apply(Apply, #c_literal{val=Fun}, Args) when is_function(Fun) -> + {module,Mod} = erlang:fun_info(Fun, module), + {name,Name} = erlang:fun_info(Fun, name), + {arity,Arity} = erlang:fun_info(Fun, arity), + if + Arity =:= length(Args) -> + #c_call{anno=Apply#c_apply.anno, + module=#c_literal{val=Mod}, + name=#c_literal{val=Name}, + args=Args}; + true -> + Apply + end; +fold_apply(Apply, _, _) -> Apply. + + %% Handling remote calls. The module/name fields have been processed. call(#c_call{args=As}=Call, #c_literal{val=M}=M0, #c_literal{val=N}=N0, Sub) -> @@ -803,6 +823,8 @@ fold_call(Call, #c_literal{val=M}, #c_literal{val=F}, Args, Sub) -> fold_call_1(Call, M, F, Args, Sub); fold_call(Call, _M, _N, _Args, _Sub) -> Call. +fold_call_1(Call, erlang, apply, [Fun,Args], _) -> + simplify_fun_apply(Call, Fun, Args); fold_call_1(Call, erlang, apply, [Mod,Func,Args], _) -> simplify_apply(Call, Mod, Func, Args); fold_call_1(Call, Mod, Name, Args, Sub) -> @@ -1111,24 +1133,38 @@ eval_failure(Call, Reason) -> %% Simplify an apply/3 to a call if the number of arguments %% are known at compile time. -simplify_apply(Call, Mod, Func, Args) -> +simplify_apply(Call, Mod, Func, Args0) -> case is_atom_or_var(Mod) andalso is_atom_or_var(Func) of - true -> simplify_apply_1(Args, Call, Mod, Func, []); - false -> Call + true -> + case get_fixed_args(Args0, []) of + error -> + Call; + {ok,Args} -> + Call#c_call{module=Mod,name=Func,args=Args} + end; + false -> + Call end. - -simplify_apply_1(#c_literal{val=MoreArgs0}, Call, Mod, Func, Args) - when length(MoreArgs0) >= 0 -> - MoreArgs = [#c_literal{val=Arg} || Arg <- MoreArgs0], - Call#c_call{module=Mod,name=Func,args=reverse(Args, MoreArgs)}; -simplify_apply_1(#c_cons{hd=Arg,tl=T}, Call, Mod, Func, Args) -> - simplify_apply_1(T, Call, Mod, Func, [Arg|Args]); -simplify_apply_1(_, Call, _, _, _) -> Call. - is_atom_or_var(#c_literal{val=Atom}) when is_atom(Atom) -> true; is_atom_or_var(#c_var{}) -> true; is_atom_or_var(_) -> false. +simplify_fun_apply(#c_call{anno=Anno}=Call, Fun, Args0) -> + case get_fixed_args(Args0, []) of + error -> + Call; + {ok,Args} -> + #c_apply{anno=Anno,op=Fun,args=Args} + end. + +get_fixed_args(#c_literal{val=MoreArgs0}, Args) + when length(MoreArgs0) >= 0 -> + MoreArgs = [#c_literal{val=Arg} || Arg <- MoreArgs0], + {ok,reverse(Args, MoreArgs)}; +get_fixed_args(#c_cons{hd=Arg,tl=T}, Args) -> + get_fixed_args(T, [Arg|Args]); +get_fixed_args(_, _) -> error. + %% clause(Clause, Cepxr, Context, Sub) -> Clause. clause(#c_clause{pats=Ps0}=Cl, Cexpr, Ctxt, Sub0) -> -- cgit v1.2.3