Enum Datum 

pub enum Datum {
    Zero(u64),
    Bytes(ByteRange),
    Scalar {
        ty: Type,
        value: Idx<Imm>,
    },
    Addr(Idx<Reloc>),
}

One piece of a global’s initial image.

Sixteen bytes, so an initializer built out of them is a flat array and a table of a million bytes is one of these rather than a million.

Variants

Zero(u64)

That many zero bytes. What .bss is made of, and what the tail of a partly initialized array is.

Bytes(ByteRange)

Those literal bytes, from the module’s byte pool. String literals and anything the frontend has already laid out.

Scalar

One scalar of that IR type, from the module’s immediate pool. An integer holds its value and a float holds its bit pattern, both target-independently: which byte comes first is decided by the datalayout when the object file is written, not here.

Fields

ty: Type

The type of the scalar, which gives its width.

value: Idx<Imm>

Its value, in the module’s immediate pool.

Addr(Idx<Reloc>)

The address of another symbol, from the module’s relocation pool. &x in an initializer, which the linker fills in.

Implementations

impl Datum

pub fn size(self, module: &Module) -> u64

How many bytes it contributes to the image.

The module is an argument because three of the four kinds keep what they are made of in one of its pools, and a datum on its own is four words that mean nothing without it.

Trait Implementations

impl Clone for Datum

fn clone(&self) -> Datum

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for Datum

impl Debug for Datum

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for Datum

impl PartialEq for Datum

fn eq(&self, other: &Datum) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for Datum