Struct llvm_ir_analysis::PostDominatorTree

pub struct PostDominatorTree<'m> { /* fields omitted */ }

The postdominator tree for a particular function.

To construct a PostDominatorTree, use FunctionAnalysis, which you can get from ModuleAnalysis.

Implementations

impl<'m> PostDominatorTree<'m>

pub fn ipostdom(&self, block: &'m Name) -> Option<CFGNode<'m>>

Get the immediate postdominator of the basic block with the given Name.

This will be None for unreachable blocks, and Some for all other blocks.

A block bbX is the immediate postdominator of bbY if and only if:

• bbX strictly postdominates bbY, i.e., bbX appears on every control-flow path from bbY to the function exit (but bbX =/= bbY)
• Of the blocks that strictly postdominate bbY, bbX is the closest to bbY (farthest from exit) along paths from bbY to the function exit

If the immediate postdominator is CFGNode::Return, that indicates that there is no single basic block that postdominates the given block.

pub fn children<'s>(
    &'s self,
    block: &'m Name
) -> impl Iterator<Item = CFGNode<'m>> + 's

Get the children of the given basic block in the postdominator tree, i.e., get all the blocks which are immediately postdominated by block.

See notes on ipostdom().

pub fn children_of_return<'s>(&'s self) -> impl Iterator<Item = &'m Name> + 's

Get the children of CFGNode::Return in the postdominator tree, i.e., get all the blocks which are immediately postdominated by CFGNode::Return.

See notes on ipostdom().

pub fn postdominates(&self, node_a: CFGNode<'m>, node_b: CFGNode<'m>) -> bool

Does node_a postdominate node_b?

Note that every node postdominates itself by definition, so if node_a == node_b, this returns true. See also strictly_postdominates()

pub fn strictly_postdominates(
    &self,
    node_a: CFGNode<'m>,
    node_b: CFGNode<'m>
) -> bool

Does node_a strictly postdominate node_b?

This is the same as postdominates(), except that if node_a == node_b, this returns false.