diff options
Diffstat (limited to 'lib/compiler/src')
-rw-r--r-- | lib/compiler/src/beam_ssa_type.erl | 94 |
1 files changed, 47 insertions, 47 deletions
diff --git a/lib/compiler/src/beam_ssa_type.erl b/lib/compiler/src/beam_ssa_type.erl index f4fc33bf4f..8b7a31849c 100644 --- a/lib/compiler/src/beam_ssa_type.erl +++ b/lib/compiler/src/beam_ssa_type.erl @@ -1293,25 +1293,10 @@ raw_type(V, Ts) -> infer_types_br(#b_var{}=V, Ts, #d{ds=Ds}) -> #{V:=#b_set{op=Op,args=Args}} = Ds, - {PosTypes0, NegTypes0} = infer_type(Op, Args, Ts, Ds), - %% We must be careful with types inferred from '=:='. - %% - %% If we have seen L =:= [a], we know that L is 'cons' if the - %% comparison succeeds. However, if the comparison fails, L could - %% still be 'cons'. Therefore, we must not subtract 'cons' from the - %% previous type of L. - %% - %% However, it is safe to subtract a type inferred from '=:=' if - %% it is single-valued, e.g. if it is [] or the atom 'true'. - - EqTypes = infer_eq_type(Op, Args, Ts, Ds), - NegTypes1 = [P || {_,T}=P <- EqTypes, beam_types:is_singleton_type(T)], + {PosTypes, NegTypes} = infer_type(Op, Args, Ts, Ds), - PosTypes = EqTypes ++ PosTypes0, SuccTs1 = meet_types(PosTypes, Ts), - - NegTypes = NegTypes0 ++ NegTypes1, FailTs1 = subtract_types(NegTypes, Ts), SuccTs = infer_br_value(V, Ts, true, SuccTs1), @@ -1337,37 +1322,8 @@ infer_br_value(V, OldTs, Bool, NewTs) -> end. infer_types_switch(V, Lit, Ts, #d{ds=Ds}) -> - Types = infer_eq_type({bif,'=:='}, [V, Lit], Ts, Ds), - meet_types(Types, Ts). - -infer_eq_type({bif,'=:='}, [#b_var{}=Src,#b_literal{}=Lit], Ts, Ds) -> - Def = maps:get(Src, Ds), - Type = raw_type(Lit, Ts), - [{Src,Type} | infer_eq_lit(Def, Lit)]; -infer_eq_type({bif,'=:='}, [#b_var{}=Arg0,#b_var{}=Arg1], Ts, _Ds) -> - %% As an example, assume that L1 is known to be 'list', and L2 is - %% known to be 'cons'. Then if 'L1 =:= L2' evaluates to 'true', it can - %% be inferred that L1 is 'cons' (the meet of 'cons' and 'list'). - Type0 = raw_type(Arg0, Ts), - Type1 = raw_type(Arg1, Ts), - Type = beam_types:meet(Type0, Type1), - [{V,MeetType} || - {V,OrigType,MeetType} <- - [{Arg0,Type0,Type},{Arg1,Type1,Type}], - OrigType =/= MeetType]; -infer_eq_type(_Op, _Args, _Ts, _Ds) -> - []. - -infer_eq_lit(#b_set{op={bif,tuple_size},args=[#b_var{}=Tuple]}, - #b_literal{val=Size}) when is_integer(Size) -> - [{Tuple,#t_tuple{exact=true,size=Size}}]; -infer_eq_lit(#b_set{op=get_tuple_element, - args=[#b_var{}=Tuple,#b_literal{val=N}]}, - #b_literal{}=Lit) -> - Index = N + 1, - Es = beam_types:set_element_type(Index, raw_type(Lit, #{}), #{}), - [{Tuple,#t_tuple{size=Index,elements=Es}}]; -infer_eq_lit(_, _) -> []. + {PosTypes, _} = infer_type({bif,'=:='}, [V, Lit], Ts, Ds), + meet_types(PosTypes, Ts). infer_type(succeeded, [#b_var{}=Src], Ts, Ds) -> #b_set{op=Op,args=Args} = maps:get(Src, Ds), @@ -1414,6 +1370,38 @@ infer_type({bif,is_number}, [Arg], _Ts, _Ds) -> infer_type({bif,is_tuple}, [Arg], _Ts, _Ds) -> T = {Arg, #t_tuple{}}, {[T], [T]}; +infer_type({bif,'=:='}, [#b_var{}=LHS,#b_var{}=RHS], Ts, _Ds) -> + %% As an example, assume that L1 is known to be 'list', and L2 is + %% known to be 'cons'. Then if 'L1 =:= L2' evaluates to 'true', it can + %% be inferred that L1 is 'cons' (the meet of 'cons' and 'list'). + LType = raw_type(LHS, Ts), + RType = raw_type(RHS, Ts), + Type = beam_types:meet(LType, RType), + + PosTypes = [{V,Type} || {V, OrigType} <- [{LHS, LType}, {RHS, RType}], + OrigType =/= Type], + + %% We must be careful with types inferred from '=:='. + %% + %% If we have seen L =:= [a], we know that L is 'cons' if the + %% comparison succeeds. However, if the comparison fails, L could + %% still be 'cons'. Therefore, we must not subtract 'cons' from the + %% previous type of L. + %% + %% However, it is safe to subtract a type inferred from '=:=' if + %% it is single-valued, e.g. if it is [] or the atom 'true'. + NegTypes = case beam_types:is_singleton_type(Type) of + true -> PosTypes; + false -> [] + end, + + {PosTypes, NegTypes}; +infer_type({bif,'=:='}, [#b_var{}=Src,#b_literal{}=Lit], Ts, Ds) -> + Def = maps:get(Src, Ds), + Type = raw_type(Lit, Ts), + EqLitTypes = infer_eq_lit(Def, Lit), + PosTypes = [{Src,Type} | EqLitTypes], + {PosTypes, EqLitTypes}; infer_type(_Op, _Args, _Ts, _Ds) -> {[], []}. @@ -1433,6 +1421,18 @@ infer_success_type(bs_start_match, [#b_var{}=Bin], _Ts, _Ds) -> infer_success_type(_Op, _Args, _Ts, _Ds) -> {[], []}. +infer_eq_lit(#b_set{op={bif,tuple_size},args=[#b_var{}=Tuple]}, + #b_literal{val=Size}) when is_integer(Size) -> + [{Tuple,#t_tuple{exact=true,size=Size}}]; +infer_eq_lit(#b_set{op=get_tuple_element, + args=[#b_var{}=Tuple,#b_literal{val=N}]}, + #b_literal{}=Lit) -> + Index = N + 1, + Es = beam_types:set_element_type(Index, raw_type(Lit, #{}), #{}), + [{Tuple,#t_tuple{size=Index,elements=Es}}]; +infer_eq_lit(_, _) -> + []. + join_types(Ts0, Ts1) -> if map_size(Ts0) < map_size(Ts1) -> |