Struct Moves 

pub struct Moves(/* private fields */);

Which instruction each of the allocator’s moves became.

A spill and a copy are both a mov once they are written, and so is an instruction the lowering wrote that happens to move the same register to the same address. Telling them apart afterwards by looking at them is guesswork, and a pass that guesses wrong about a store to a volatile variable deletes a read the program insisted on. So what the allocator asked for is recorded as it is written, and a later pass that is only allowed to touch the allocator’s own moves has the list rather than a heuristic. See crate::copies, which is the one pass that reads this.

It is kept by instruction number rather than in a hash map, because that pass asks about every instruction in the function and the numbers are dense.

Implementations

impl Moves

pub fn at(&self, inst: Inst) -> Option<Edit>

What the allocator asked for at this instruction, or None at an instruction that is not one of its moves.

pub fn record(&mut self, inst: Inst, edit: Edit)

Records that this instruction is what that move came to.

Trait Implementations

impl Debug for Moves

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

Formats the value using the given formatter.

impl Default for Moves

fn default() -> Self

Returns the “default value” for a type.