pub fn is_valid_linear_scan(
spec: &RegSpec,
assignment: &[Option<usize>],
) -> boolExpand description
Re-check a linear-scan assignment: every assigned register is within budget, and no two variables
that are live at the same time are given the same register — the soundness property any register
allocation must satisfy. (Spilled variables, None, impose no constraint: they live in memory.)