Example #1
0
    def isinstance_native(self, obj: Value, class_ir: ClassIR,
                          line: int) -> Value:
        """Fast isinstance() check for a native class.

        If there three or less concrete (non-trait) classes among the class and all
        its children, use even faster type comparison checks `type(obj) is typ`.
        """
        concrete = all_concrete_classes(class_ir)
        if concrete is None or len(
                concrete) > FAST_ISINSTANCE_MAX_SUBCLASSES + 1:
            return self.primitive_op(fast_isinstance_op,
                                     [obj, self.get_native_type(class_ir)],
                                     line)
        if not concrete:
            # There can't be any concrete instance that matches this.
            return self.primitive_op(false_op, [], line)
        type_obj = self.get_native_type(concrete[0])
        ret = self.primitive_op(type_is_op, [obj, type_obj], line)
        for c in concrete[1:]:

            def other() -> Value:
                return self.primitive_op(type_is_op,
                                         [obj, self.get_native_type(c)], line)

            ret = self.shortcircuit_helper('or', bool_rprimitive, lambda: ret,
                                           other, line)
        return ret
Example #2
0
    def emit_cast(self,
                  src: str,
                  dest: str,
                  typ: RType,
                  declare_dest: bool = False,
                  custom_message: Optional[str] = None,
                  optional: bool = False,
                  src_type: Optional[RType] = None,
                  likely: bool = True) -> None:
        """Emit code for casting a value of given type.

        Somewhat strangely, this supports unboxed types but only
        operates on boxed versions.  This is necessary to properly
        handle types such as Optional[int] in compatibility glue.

        Assign NULL (error value) to dest if the value has an incompatible type.

        Always copy/steal the reference in src.

        Args:
            src: Name of source C variable
            dest: Name of target C variable
            typ: Type of value
            declare_dest: If True, also declare the variable 'dest'
            likely: If the cast is likely to succeed (can be False for unions)
        """
        if custom_message is not None:
            err = custom_message
        else:
            err = 'CPy_TypeError("{}", {});'.format(self.pretty_name(typ), src)

        # Special case casting *from* optional
        if src_type and is_optional_type(
                src_type) and not is_object_rprimitive(typ):
            value_type = optional_value_type(src_type)
            assert value_type is not None
            if is_same_type(value_type, typ):
                if declare_dest:
                    self.emit_line('PyObject *{};'.format(dest))
                check = '({} != Py_None)'
                if likely:
                    check = '(likely{})'.format(check)
                self.emit_arg_check(src, dest, typ, check.format(src),
                                    optional)
                self.emit_lines('    {} = {};'.format(dest, src), 'else {',
                                err, '{} = NULL;'.format(dest), '}')
                return

        # TODO: Verify refcount handling.
        if (is_list_rprimitive(typ) or is_dict_rprimitive(typ)
                or is_set_rprimitive(typ) or is_float_rprimitive(typ)
                or is_str_rprimitive(typ) or is_int_rprimitive(typ)
                or is_bool_rprimitive(typ)):
            if declare_dest:
                self.emit_line('PyObject *{};'.format(dest))
            if is_list_rprimitive(typ):
                prefix = 'PyList'
            elif is_dict_rprimitive(typ):
                prefix = 'PyDict'
            elif is_set_rprimitive(typ):
                prefix = 'PySet'
            elif is_float_rprimitive(typ):
                prefix = 'CPyFloat'
            elif is_str_rprimitive(typ):
                prefix = 'PyUnicode'
            elif is_int_rprimitive(typ):
                prefix = 'PyLong'
            elif is_bool_rprimitive(typ):
                prefix = 'PyBool'
            else:
                assert False, 'unexpected primitive type'
            check = '({}_Check({}))'
            if likely:
                check = '(likely{})'.format(check)
            self.emit_arg_check(src, dest, typ, check.format(prefix, src),
                                optional)
            self.emit_lines('    {} = {};'.format(dest, src), 'else {', err,
                            '{} = NULL;'.format(dest), '}')
        elif is_tuple_rprimitive(typ):
            if declare_dest:
                self.emit_line('{} {};'.format(self.ctype(typ), dest))
            check = '(PyTuple_Check({}))'
            if likely:
                check = '(likely{})'.format(check)
            self.emit_arg_check(src, dest, typ, check.format(src), optional)
            self.emit_lines('    {} = {};'.format(dest, src), 'else {', err,
                            '{} = NULL;'.format(dest), '}')
        elif isinstance(typ, RInstance):
            if declare_dest:
                self.emit_line('PyObject *{};'.format(dest))
            concrete = all_concrete_classes(typ.class_ir)
            n_types = len(concrete)
            # If there are too many concrete subclasses or we can't find any
            # (meaning the code ought to be dead), fall back to a normal typecheck.
            # Otherwise check all the subclasses.
            if n_types == 0 or n_types > FAST_ISINSTANCE_MAX_SUBCLASSES + 1:
                check = '(PyObject_TypeCheck({}, {}))'.format(
                    src, self.type_struct_name(typ.class_ir))
            else:
                full_str = '(Py_TYPE({src}) == {targets[0]})'
                for i in range(1, n_types):
                    full_str += ' || (Py_TYPE({src}) == {targets[%d]})' % i
                if n_types > 1:
                    full_str = '(%s)' % full_str
                check = full_str.format(
                    src=src,
                    targets=[self.type_struct_name(ir) for ir in concrete])
            if likely:
                check = '(likely{})'.format(check)
            self.emit_arg_check(src, dest, typ, check, optional)
            self.emit_lines('    {} = {};'.format(dest, src), 'else {', err,
                            '{} = NULL;'.format(dest), '}')
        elif is_none_rprimitive(typ):
            if declare_dest:
                self.emit_line('PyObject *{};'.format(dest))
            check = '({} == Py_None)'
            if likely:
                check = '(likely{})'.format(check)
            self.emit_arg_check(src, dest, typ, check.format(src), optional)
            self.emit_lines('    {} = {};'.format(dest, src), 'else {', err,
                            '{} = NULL;'.format(dest), '}')
        elif is_object_rprimitive(typ):
            if declare_dest:
                self.emit_line('PyObject *{};'.format(dest))
            self.emit_arg_check(src, dest, typ, '', optional)
            self.emit_line('{} = {};'.format(dest, src))
            if optional:
                self.emit_line('}')
        elif isinstance(typ, RUnion):
            self.emit_union_cast(src, dest, typ, declare_dest, err, optional,
                                 src_type)
        elif isinstance(typ, RTuple):
            assert not optional
            self.emit_tuple_cast(src, dest, typ, declare_dest, err, src_type)
        else:
            assert False, 'Cast not implemented: %s' % typ