Struct regalloc2::PReg

source ·
pub struct PReg { /* private fields */ }
Expand description

A physical register. Contains a physical register number and a class.

The hw_enc field contains the physical register number and is in a logically separate index space per class; in other words, Int register 0 is different than Float register 0.

Because of bit-packed encodings throughout the implementation, hw_enc must fit in 6 bits, i.e., at most 64 registers per class.

The value returned by index(), in contrast, is in a single index space shared by all classes, in order to enable uniform reasoning about physical registers. This is done by putting the class bit at the MSB, or equivalently, declaring that indices 0..=63 are the 64 integer registers and indices 64..=127 are the 64 float registers.

Implementations§

Create a new PReg. The hw_enc range is 6 bits.

The physical register number, as encoded by the ISA for the particular register class.

The register class.

Get an index into the (not necessarily contiguous) index space of all physical registers. Allows one to maintain an array of data for all PRegs and index it efficiently.

Construct a PReg from the value returned from .index().

Return the “invalid PReg”, which can be used to initialize data structures.

Trait Implementations§

Returns a copy of the value. Read more
Performs copy-assignment from source. Read more
Formats the value using the given formatter. Read more
Formats the value using the given formatter. Read more
Feeds this value into the given Hasher. Read more
Feeds a slice of this type into the given Hasher. Read more
This method returns an Ordering between self and other. Read more
Compares and returns the maximum of two values. Read more
Compares and returns the minimum of two values. Read more
Restrict a value to a certain interval. Read more
This method tests for self and other values to be equal, and is used by ==. Read more
This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason. Read more
This method returns an ordering between self and other values if one exists. Read more
This method tests less than (for self and other) and is used by the < operator. Read more
This method tests less than or equal to (for self and other) and is used by the <= operator. Read more
This method tests greater than (for self and other) and is used by the > operator. Read more
This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more

Auto Trait Implementations§

Blanket Implementations§

Gets the TypeId of self. Read more
Immutably borrows from an owned value. Read more
Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

The resulting type after obtaining ownership.
Creates owned data from borrowed data, usually by cloning. Read more
Uses borrowed data to replace owned data, usually by cloning. Read more
Converts the given value to a String. Read more
The type returned in the event of a conversion error.
Performs the conversion.
The type returned in the event of a conversion error.
Performs the conversion.