Struct UseDefChain 

pub struct UseDefChain {
    pub uses: HashMap<LcnfVarId, Vec<LcnfVarId>>,
    pub defs: HashMap<LcnfVarId, LcnfLetValue>,
}

Bidirectional use-def / def-use chains for the IR.

• defs[x] = the let-value that defines x (there is exactly one in SSA).
• uses[x] = all variables that reference x in their definitions.

Fields

uses: HashMap<LcnfVarId, Vec<LcnfVarId>>

Forward: variable → all variables that use it.

defs: HashMap<LcnfVarId, LcnfLetValue>

Backward: variable → its defining expression.

Implementations

impl UseDefChain

pub fn new() -> Self

pub fn add_use(&mut self, used: LcnfVarId, user: LcnfVarId)

Record that user reads used.

pub fn add_def(&mut self, var: LcnfVarId, value: LcnfLetValue)

Record the definition of var.

pub fn has_uses(&self, var: &LcnfVarId) -> bool

Return true if var has at least one use.

Trait Implementations

impl Debug for UseDefChain

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

Formats the value using the given formatter.

impl Default for UseDefChain

fn default() -> UseDefChain

Returns the “default value” for a type.