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<OperandConstraint> 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 StructuralEq for OperandConstraint

impl StructuralPartialEq for OperandConstraint