Struct Cfg 

pub struct Cfg {
    pub blocks: Vec<BasicBlock>,
    pub entry: usize,
}

Fields

blocks: Vec<BasicBlock>

entry: usize

Implementations

impl Cfg

pub fn build(program: &Program) -> Cfg

Build a CFG from a compiled program. Sub-programs become their own blocks recursively; the returned entry is the root block id.

pub fn size(&self) -> usize

Number of basic blocks in the graph.

pub fn reachable(&self) -> Vec<usize>

Reachable blocks from entry via BFS.

pub fn dominators(&self) -> Vec<Option<usize>>

Compute immediate dominators by iterative dataflow (Cooper–Harvey–Kennedy).

pub fn preds(&self) -> Vec<Vec<usize>>

Predecessor list per block.

pub fn dominance_frontiers(&self) -> Vec<HashSet<usize>>

Dominance frontier per block (Cytron et al.).

pub fn loop_headers(&self) -> Vec<(usize, usize)>

Loop headers: blocks that dominate one of their own predecessors (i.e. back-edges terminate here). Returns (header, back_edge_source).

impl Cfg

pub fn liveness(&self) -> Liveness

Compute live-in / live-out sets for identifiers (variables) across the CFG using standard backward dataflow. A variable is live at a point if a LoadIdent for it exists on some path to the exit.

impl Cfg

pub fn allocate_slots(&self, live: &Liveness) -> SlotMap

Assign a compact slot index per ident using greedy graph colouring over the interference graph derived from liveness. Names live at the same block interfere; greedy picks the lowest free slot.

Trait Implementations

impl Clone for Cfg

fn clone(&self) -> Cfg

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Cfg

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

Formats the value using the given formatter.