1.2 KiB
Semantic Bit Index
This type is a counter in the ring 0 .. R::BITS and serves to mark a semantic
index within some register element. It is a virtual index, and is the stored
value used in pointer encodings to track region start information.
It is translated to a real index through the BitOrder trait. This virtual
index is the only counter that can be used for address computation, and once
lowered to an electrical index through BitOrder::at, the electrical address
can only be used for setting up machine instructions.
Type Parameters
R: The register element that this index governs.
Validity
Values of this type are required to be in the range 0 .. R::BITS. Any
value not less than R::BITS makes the program invalid, and will likely cause
either a crash or incorrect memory access.
Construction
This type can never be constructed outside of the bitvec crate. It is passed
in to BitOrder implementations, which may use it to construct electrical
position values from it. All values of this type constructed by bitvec are
known to be correct in their region; no other construction site can be trusted.