Struct cranelift_codegen::isa::registers::RegClassData [−][src]
pub struct RegClassData { pub name: &'static str, pub index: u8, pub width: u8, pub bank: u8, pub toprc: u8, pub first: RegUnit, pub subclasses: RegClassMask, pub mask: RegUnitMask, pub info: &'static RegInfo, pub pinned_reg: Option<RegUnit>, }
Expand description
Data about a register class.
A register class represents a subset of the registers in a bank. It describes the set of permitted registers for a register operand in a given encoding of an instruction.
A register class can be a subset of another register class. The top-level register classes are disjoint.
Fields
name: &'static str
The name of the register class.
index: u8
The index of this class in the ISA’s RegInfo description.
width: u8
How many register units to allocate per register.
bank: u8
Index of the register bank this class belongs to.
toprc: u8
Index of the top-level register class contains this one.
first: RegUnit
The first register unit in this class.
subclasses: RegClassMask
Bit-mask of sub-classes of this register class, including itself.
Bits correspond to RC indexes.
mask: RegUnitMask
Mask of register units in the class. If width > 1
, the mask only has a bit set for the
first register unit in each allocatable register.
info: &'static RegInfo
The global RegInfo
instance containing this register class.
pinned_reg: Option<RegUnit>
The “pinned” register of the associated register bank.
This register must be non-volatile (callee-preserved) and must not be the fixed output register of any instruction.
Implementations
Get the register class index corresponding to the intersection of self
and other
.
This register class is guaranteed to exist if the register classes overlap. If the register
classes don’t overlap, returns None
.
Get the intersection of self
and other
.
Returns true if other
is a subclass of this register class.
A register class is considered to be a subclass of itself.
If the pinned register is used, is the given regunit the pinned register of this class?
Trait Implementations
Within an ISA, register classes are uniquely identified by their index.