diff options
Diffstat (limited to 'lib/hipe')
| -rw-r--r-- | lib/hipe/cerl/erl_bif_types.erl | 52 |
1 files changed, 48 insertions, 4 deletions
diff --git a/lib/hipe/cerl/erl_bif_types.erl b/lib/hipe/cerl/erl_bif_types.erl index acc7366d6b..10d60a4c9a 100644 --- a/lib/hipe/cerl/erl_bif_types.erl +++ b/lib/hipe/cerl/erl_bif_types.erl @@ -366,7 +366,7 @@ type(erlang, '>', 2, Xs = [Lhs, Rhs]) -> is_integer(LhsMax), is_integer(RhsMin), RhsMin >= LhsMax -> F; true -> t_boolean() end; - false -> t_boolean() + false -> compare('>', Lhs, Rhs) end, strict(Xs, Ans); type(erlang, '>=', 2, Xs = [Lhs, Rhs]) -> @@ -384,7 +384,7 @@ type(erlang, '>=', 2, Xs = [Lhs, Rhs]) -> is_integer(LhsMax), is_integer(RhsMin), RhsMin > LhsMax -> F; true -> t_boolean() end; - false -> t_boolean() + false -> compare('>=', Lhs, Rhs) end, strict(Xs, Ans); type(erlang, '<', 2, Xs = [Lhs, Rhs]) -> @@ -402,7 +402,7 @@ type(erlang, '<', 2, Xs = [Lhs, Rhs]) -> is_integer(LhsMin), is_integer(RhsMax), RhsMax =< LhsMin -> F; true -> t_boolean() end; - false -> t_boolean() + false -> compare('<', Lhs, Rhs) end, strict(Xs, Ans); type(erlang, '=<', 2, Xs = [Lhs, Rhs]) -> @@ -420,7 +420,7 @@ type(erlang, '=<', 2, Xs = [Lhs, Rhs]) -> is_integer(LhsMin), is_integer(RhsMax), RhsMax < LhsMin -> F; true -> t_boolean() end; - false -> t_boolean() + false -> compare('=<', Lhs, Rhs) end, strict(Xs, Ans); type(erlang, '+', 1, Xs) -> @@ -3179,6 +3179,50 @@ arith(Op, X1, X2) -> end. %%============================================================================= +%% Comparison of terms +%%============================================================================= + +compare(Op, Lhs, Rhs) -> + case t_is_none(t_inf(Lhs, Rhs)) of + false -> t_boolean(); + true -> + case Op of + '<' -> always_smaller(Lhs, Rhs); + '>' -> always_smaller(Rhs, Lhs); + '=<' -> always_smaller(Lhs, Rhs); + '>=' -> always_smaller(Rhs, Lhs) + end + end. + +always_smaller(Type1, Type2) -> + {Min1, Max1} = type_ranks(Type1), + {Min2, Max2} = type_ranks(Type2), + if Max1 < Min2 -> t_atom('true'); + Min1 > Max2 -> t_atom('false'); + true -> t_boolean() + end. + +type_ranks(Type) -> + type_ranks(Type, 1, 0, 0, type_order()). + +type_ranks(_Type, _I, Min, Max, []) -> {Min, Max}; +type_ranks(Type, I, Min, Max, [TypeClass|Rest]) -> + {NewMin, NewMax} = + case t_is_none(t_inf(Type, TypeClass)) of + true -> {Min, Max}; + false -> case Min of + 0 -> {I, I}; + _ -> {Min, I} + end + end, + type_ranks(Type, I+1, NewMin, NewMax, Rest). + +type_order() -> + [t_number(), t_atom(), t_reference(), t_fun(), t_port(), t_pid(), t_tuple(), + t_list(), t_binary()]. + + +%%============================================================================= -spec arg_types(atom(), atom(), arity()) -> [erl_types:erl_type()] | 'unknown'. |