The Bit_Order attribute specifies the interpretation
of the storage place attributes.
A bit ordering is a method of
interpreting the meaning of the storage place attributes.
High_Order_First
(known in the vernacular as “big endian”) means that the
first bit of a storage element (bit 0) is the most significant bit (interpreting
the sequence of bits that represent a component as an unsigned integer
value).
Low_Order_First
(known in the vernacular as “little endian”) means the opposite:
the first bit is the least significant.
Denotes the bit ordering for
the type of S. The value of this attribute is of type System.Bit_Order.
Bit_Order may be specified for
specific record types via an
attribute_definition_clause;
the expression of such a clause shall be static.
If Word_Size = Storage_Unit, the default bit ordering
is implementation defined. If Word_Size > Storage_Unit, the default
bit ordering is the same as the ordering of storage elements in a word,
when interpreted as an integer.
The storage place attributes of a component of a
type are interpreted according to the bit ordering of the type.
The implementation should support the nondefault
bit ordering in addition to the default bit ordering.
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