Struct EqualityAnalysis 

pub struct EqualityAnalysis<'a, 'db> { /* private fields */ }

Variable equality analysis.

This analyzer tracks snapshot/desnap, box/unbox, struct construct, and array construct relationships as data flows through the program. At merge points (after match arms converge), we union-find variables that share the same equivalence classes in both branches ((rep1, rep2) meet), rebuild forward / reverse, and intersect relations without mapping variables across differing branch-local equivalence roots (structure fields fall back to placeholders).

Implementations

impl<'a, 'db> EqualityAnalysis<'a, 'db>

pub fn new(db: &'db dyn Database, lowered: &'a Lowered<'db>) -> Self

Creates a new equality analysis instance.

pub fn analyze( db: &'db dyn Database, lowered: &'a Lowered<'db>, ) -> Vec<Option<EqualityState<'db>>>

Runs equality analysis on a lowered function. Returns the equality state at the exit of each block.

Trait Implementations

impl<'db, 'a> DataflowAnalyzer<'db, 'a> for EqualityAnalysis<'a, 'db>

const DIRECTION: Direction = Direction::Forward

The direction of this analysis.

type Info = EqualityState<'db>

The analysis state/info type.

fn initial_info( &mut self, _block_id: BlockId, _block_end: &'a BlockEnd<'db>, ) -> Self::Info

Create the initial analysis state at a terminal block.

fn merge( &mut self, _lowered: &Lowered<'db>, _statement_location: StatementLocation, info1: Self::Info, info2: Self::Info, ) -> Self::Info

Merge/join states from multiple control flow paths. Called at join points (match merge for backward, block entry for forward).

fn transfer_stmt( &mut self, info: &mut Self::Info, _statement_location: StatementLocation, stmt: &'a Statement<'db>, )

Transfer function for a single statement.

fn transfer_edge( &mut self, info: &Self::Info, edge: &Edge<'db, 'a>, ) -> Self::Info

Transfer state along a CFG edge. Called when traversing between blocks via control flow edges.

fn transfer_block( &mut self, info: &mut Self::Info, block_id: BlockId, block: &'a Block<'db>, )

Transfer function for an entire block.

fn visit_block_start( &mut self, _info: &mut Self::Info, _block_id: BlockId, _block: &Block<'db>, )

Called when entering a block during traversal (before transfer_block).

fn block_entry_location( &self, lowered: &Lowered<'db>, block_id: BlockId, ) -> LocationId<'db>

Block entry location. For Backward it is the merge location. For Forward it is the block entry location, if there is a statement. If not statement exists it will look at block end. This might recurse to next block if we have a goto with no remappings.