Enum regalloc2::OperandConstraint

pub enum OperandConstraint {
    Any,
    Reg,
    Stack,
    FixedReg(PReg),
    Reuse(usize),
}

An OperandConstraint specifies where a vreg’s value must be placed at a particular reference to that vreg via an Operand. The constraint may be loose – “any register of a given class”, for example – or very specific, such as “this particular physical register”. The allocator’s result will always satisfy all given constraints; however, if the input has a combination of constraints that are impossible to satisfy, then allocation may fail or the allocator may panic (providing impossible constraints is usually a programming error in the client, rather than a function of bad input).

Variants

Any

Any location is fine (register or stack slot).

Reg

Operand must be in a register. Register is read-only for Uses.

Stack

Operand must be on the stack.

FixedReg(PReg)

Operand must be in a fixed register.

Reuse(usize)

On defs only: reuse a use’s register.

Trait Implementations

impl Clone for OperandConstraint

fn clone(&self) -> OperandConstraint

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for OperandConstraint

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

Formats the value using the given formatter.

impl Display for OperandConstraint

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

Formats the value using the given formatter.

impl PartialEq for OperandConstraint

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

This method tests for self and other values to be equal, and is used by ==.

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

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for OperandConstraint

impl Eq for OperandConstraint

impl StructuralPartialEq for OperandConstraint